Monthly Archives: January 2010

Recent Developments in Biosensors

Novel ideas in engineering nanomaterials and thin films technology are under development in near patient testing applications, for example, using quantum dots (Goldman et al 2002, Pathak et al 2007); nanowire based field detector (Wang et al 2005); layer of silica coated nano-magnet with higher biocatalystic sensitivity, and encapsulation of radioisotopes in CNTs and nano-carbon onions, as examples of synthesis of materials (magnetic, radionuclide) for medical diagnosis (Tsang, Oxford 2009).

Fig 14 – To scale model of a SWNT tip that has been modified with biotin and is interacting with streptavidin.(Woolley et al 2000)

Security applications exploit spectral characteristics and imaging in terahertz domain, which is capable to travel through materials that block light (Tonouchi 2007, Baker 2007). Terahertz sensing technique combined with surface plasmon polaritons with unique imaging results of superfocus pulsed terahertz radiation is developed to visualize below surface of objects (Johnston M 2007, Davies 2008). THz spectroscopy measures changes of both amplitude and phase not only intensity of transient electric field thus, provides simultaneous information on the absorption coefficient and index of refraction (Schmuttenmaer 2004). Photonics are key players for development of THz devices such as quantum cascade laser QCL or THz single photon detector.

In multiplexed arrayed formats different antibodies can be functionalized in single wall nanotubes SWNTs for protein detection. SWNTs display sharp scattering peaks when functionalized as coloured biomarkers for Raman labels due to strong sensitivity of SERS substrates. Super conducting Quantum Interference Device SQUID measurements for detection of prostate-specific antigen PSA is targeted using Magnetic Nanoparticles MNPs functionalized by biotin/streptavidin in a mono-dispersed stable solution able to track binding events in real time. Frequency and time domain characterization of changes in MNPs improved sensitivity to smaller sample volume down to 2 μl, and to as few as 100 million MNPs (Oisjoen et al 2010, Eberbeck et al 2008).

Following increasing R&D in biosensors to create precision techniques many technology transfer spin outs are emerged from universities to commercialize novel diagnostic devices. Comprehensive records of UK spin out companies are available by KTN (Knowledge Transfer Network), which includes Oxford Medical Diagnostics; Oxford Nanolabs; Oxford Catalysts; Oxford Advanced Surfaces and OxTox to name a few. Commercialized instruments are also launched in the United States and Europe for example, GWC technologies (Madioson USA) IBIS Technologies B V (Hengelo, The Netherlands), Genoptics Bio Interactions (Orsay France), GE Healthcare (Uppsala, Sweden). Nonetheless, Newman recent review of the industry points out that biosensors are still far from common use, with glucose biosensors mostly disposable test strips accounting for 85% of the world market, which is estimated at around 5 billion dlrs per annum. Abbott laboratories, Bayer diagnostics, LifeScan, and Roche diagnostics are among active players (Newman et al 2004, Davis et al 2004)).

 

Advertisements

Leave a comment

Filed under Uncategorized

Characterisation of Biosensors

Bionanosensors based on biochip technology are particular type of sensors with silicon as underlying substrates, functionalised by immobilised Self Assembled Monolayers SAMs. They have seen wide application for rapid analysis, quantification and recognition of biomolecules. Miniaturisation of bionanosensors, not only increased sensitivity and detection power down to micro-nano concentration but also uses less materials, is cheaper and easier to handle, making them more environmental friendly for bottom up fabrication.

Bionanosensors used for selective detection of biomolecules can be categorized into general principles of I) affinity – antibody/antigen II) enzyme/substrate, and III) nucleic acids/complementary sequences. Biosensor devices based on SAMs found wide and growing applications in bio-sensing, wetting control and surface modification.

Fabrications of immunoassay microarrays as custom-made protein chips are under intense investigation to inform large-scale proteomics activities. Protein microarrays use similar technique for DNA microarrays printed with numerous protein detectors and analyzed by time-of-flight mass spectrometry and peptide mass fingerprinting.

Novel ideas in engineering nanomaterials and thin films technology are under further development for use as biosensors in near patient testing applications, for example, using quantum dots; nanowire-based field detector; layer of silica coated nano-magnet with higher biocatalystic sensitivity, and encapsulation of radioisotopes in CNTs and nano-carbon onions, as new ways of synthesis of materials (magnetic, radionuclide) used for medical diagnosis.

Super conducting Quantum Interference Device SQUID measurements for detection of prostate-specific antigen PSA is another target using Magnetic Nanoparticles MNPs functionalized by biotin/streptavidin in a mono-dispersed stable solution able to track binding events in real time.

Variety of applications for antigen-antibody sensors are developing in areas of diagnostics, pharmaceutical and food industry, as well as environmental control and protection, detecting bacterial cells, virus, fungi and so on, and so forth. Biosensors are to become disruptive analytical technology in range of fields of medicine, agriculture, environment, security and manufacturing monitoring.

Jamie H.Warner, Neil P. Young, Angus I. Kirkland and G. Andrew D. Briggs, Resolving strain in carbon nanotubes at the atomic level, Nature Materials, Vol 10, Dec 2011- (Oxford University)

Understanding the mechanical properties of nanomaterials at the atomic-scale is of great importance for their utilization in nanoelectromechanical systems (NEMS), especially in light of the recent observation of quantum phenomena on the macroscopic scale1. Suspended SWNTs, with their remarkably high tensile strengths2 and elasticity, are ideal oscillators for NEMS (ref. 3) and predicting their resonant frequency characteristics accurately requires the incorporation of shear strain, such as in the Timoshenko beam model4, 5, or possibly even non-local strain models6. When a nanotube is elastically distorted, an understanding of how the atomic structure compensates under stress has yet to be experimentally realized7, 8, 9, 10. Knowledge of whether there is compression or stretching of the C–C bonds is vital for building a deeper understanding of the behaviour of nanotubes at the atomic level. Deviation of a SWNT from its pristine structure can occur by bending perpendicular to its axis, distortion of the cross-section from circular to elliptical, or a rotational twist about the axis. To resolve these distortions information about the atomic structure is necessary.

The incorporation of aberration correctors into transmission electron microscopes has opened up a new field in performing atomic-resolution microscopy at low accelerating voltages11, 12, 13, 14, 15. This has been revolutionary for carbon nanomaterials, where a low accelerating voltage of 80 kV is needed to reduce knock-on damage to sp2 carbon nanomaterials such as SWNTs (ref. 16), graphene12, 14, 17, 18, fullerenes and peapods19, 20. The ability to resolve carbon lattice structure with high-resolution transmission electron microscopy (HRTEM) enables information to be determined that reveals defects, holes and layer stacking in graphene11, 12, 14, 17, 18. In carbon nanotubes HRTEM has been used to determine the chirality of SWNTs and double-walled carbon nanotubes (DWNTs; refs 21, 22), as well as see lattice defects13.

Until now there has been a lack of experimental evidence regarding how the atomic structure of a carbon nanotube changes under strain from bending. For large bending angles, buckling of the SWNT is observed23. However in most cases SWNTs are well below their buckling limit and only slightly distorted in their shape. Resolving strain at the atomic level is at the forefront of structural characterization using aberration-corrected HRTEM (AC-HRTEM; ref.  24). Jia et al. have examined shifts in atomic positions in ferroelectrics by least-squares fitting with 2D Gaussian profiles using AC-HRTEM at an accelerating voltage of 200 kV (ref. 25). Geometrical phase analysis (GPA) methods have been used for measuring the displacement field of dislocations in silicon26. This has also been used for evaluating the strain matrix for PbTiO3, diamond and cubic boron nitride crystal structures27, 28. This GPA approach is based on local filtering of specific reflections in Fourier space. Real space methods for evaluating elastic strain, such as the ‘Peak Pairs’ algorithm, work by examining the positions of intensity maxima and comparing these to predicted positional values29, 30. Both of these approaches have shown great success in examining dislocations and grain boundaries where there is an abrupt change to the atomic structure. The high asymmetry of carbon nanotubes creates complications when applying these methods in their case, as does the curvature of the hexagonal graphitic lattice.

We have used AC-HRTEM to examine SWNTs that were deposited from a solution of 1,2-dichloroethane onto a lacey carbon-coated TEM grid. This resulted in isolated nanotubes suspended across free space and enabled substrate-free imaging. The bending observed in the SWNTs is a direct consequence of drying from the solvent and becoming fixed onto the lacey grid. Most SWNTs are chiral in nature and this produces a moiré interference pattern between the top and bottom layer. Figure 1a shows a (18,8) SWNT with a strong moiré pattern. To obtain the position of each atom, the top and bottom layers need to be separated by applying a mask to the 2D Fast Fourier Transform. It is possible in this way to observe large-scale defects in this type of SWNT (see Supplementary Information). However, this type of filtering can induce artefacts in the contrast of the reconstructed image that prevent confidence in the interpretation of the atomic structure. To avoid this problem we present our examination of a non-chiral SWNT with (28,0) chirality, which is free from complicated moiré interference patterns.

Figure 1: Low-voltage AC-HRTEM images of SWNTs.
Low-voltage AC-HRTEM images of SWNTs.

a, (18,8) SWNT. b, A (28,0) zig-zag SWNT suspended in free space with a bend. c, At higher magnification showing the full atomic structure.

Figure 1b shows a zig-zag (28,0) SWNT suspended across a distance of 28 nm. The curvature in the nanotube is observed and measured as an angular deviation of 5.4° over a length of approximately 10 nm. The region of strain is highlighted by the blue box in Fig. 1a and is shown at higher magnification in Fig. 1c. The SWNT was indexed as having (28,0) chirality by analysing the 2D Fast Fourier Transform, combined with image simulations and diameter measurements (see Supplementary Information). The positions of individual atomic columns were accurately determined. A crucial parameter to obtaining high spatial resolution information is that the drift of the stage and sample vibrations be less than 0.1 nm for the entire 2 s integration time required to capture the image with sufficient signal-to-noise ratio. Careful examination of Fig. 1c shows that the angle of the zig-zag segments relative to the axis of the SWNT changes. At the right-hand side, the zig-zag segment is 90° with respect to the sidewall, and progressing further to the left-hand end shows an increase of this angle up to 92°.

Precise knowledge of the position of the atoms enables a 2D atomic displacement map to be constructed. This is achieved by first producing an image simulation of a perfect crystalline (28,0) SWNT, as shown in Fig. 2a, based on the atomic model of a (28,0) SWNT. A reference point was chosen in the bottom right-hand corner (shown with a blue spot in Fig. 2a,b) and the coordinate of each atomic column recorded. The positions of the atomic columns are measured for the experimental image (Fig. 2b) and the magnitude of the displacement calculated by subtracting the positions from the pristine crystal in Fig. 2a. Figure 2c shows the atomic column positions for the perfect crystal lattice (blue diamonds) from Fig. 2a and experimentally measured values from Fig. 2b (red squares) of the strained SWNT. The origin is defined at the bottom right so that the magnitude of the displacement is positive for the shearing in Fig. 2b. Figure 2d plots the magnitude of displacement, Ut, in colour representation at each atomic column in the real HRTEM image, with the colour scale in picometres shown to the right.

Figure 2: Obtaining a 2D displacement map of a (28,0) SWNT.
Obtaining a 2D displacement map of a (28,0) SWNT.

a, HRTEM image simulation of a (28,0) SWNT. Scale bar, 500 pm. b, Experimental AC-HRTEM image of a (28,0) SWNT with strain, taken from the blue boxed region in Fig. 1c. Scale bar, 500 pm. c, Overlay of atomic column positions measured from a (28,0) SWNT in simulated (a) (blue) and experimental (b) (red) HRTEM images. d, 2D displacement map, Ut, overlaid on top of the HRTEM from b.

The 2D displacement map presented in Fig. 2d shows an increase in Ut towards the top left-hand side of the SWNT, with shifts of up to 143 pm. Changes in the diameter of the SWNT are also apparent along the axis. The displacement gradient matrix, ɛij, provides vital information related to distortions and rotations of materials31.

The displacement gradient matrix can be expanded as31

where ɛ1 is a symmetric component that represents distortions described by the linearized strain matrix, S, and ɛ2 is an anti-symmetric component describing rotations. Thus, taking the derivative of the x and y components of the 2D displacement field Ut will provide insights into the nature of the distortions and rotations within the SWNT. Figure 3a,b shows the 2D displacement map separated into its x and y components, Ux and Uy. As we are dealing with atomic positions and not a continuum of Ut, the derivative of the displacement field is achieved by discretization, for example Ux/y becomes ΔUxy and the gradient is determined between two points. We found that ΔUx is small for nearest-neighbour atoms and comparable to the uncertainty in the position determination of x and y. Thus, a larger separation of atomic positions is needed to obtain maps of the gradients of Ux and Uy that are interpretable. Further complications arise owing to the hexagonal nature of the lattice and its curvature in SWNTs. Details of the methods to produce Fig. 3c–f are found in the Supplementary Information. Figure 3c–f show the 2D maps of Ux/x, Uy/x, Ux/y and Uy/y respectively. The mismatch in dimensions of Uy/x and Ux/y prevent the data from being further processed to obtain the strain matrix. However, a description of the displacement field Ut(x,y)can be derived if we consider how Ux,Uy and their relative gradients vary in magnitude as a function of x and y. This model of Ut(x,y) can then be used to determine the distortion and rotation in the system.

Figure 3: X and Y components of the 2D displacement map and the 2D gradient maps.
X and Y components of the 2D displacement map and the 2D gradient maps.

af, Analysis of the x and y components of the 2D displacement map from experimental images in Fig. 2. a, 2D displacement map for x component Ux overlaid on TEM image. Scale bar, 500 pm. b, 2D displacement map for y component Uyoverlaid on TEM image. c, 2D map of Ux/x. d, 2D map of Uy/x. e, 2D map of Ux/y. f, 2D map of Uy/y. gl, Analysis of displacement map for model (28,0)SWNT with the applied model strain, Ux=Cxy and Uy=(−Dx2+Ex)+(−Fy2+Gy), where C,D,E,F and G are all constants. g, 2D displacement map for x component Ux overlaid on TEM image. h, 2D displacement map for y component Uyoverlaid on TEM image. i, 2D map of Ux/x. j, 2D map of Uy/x. k, 2D map of Uy/x. l, 2D map of Uy/y. White arrows indicate the direction of increasing gradient.

Both Ux and Uy increase with x and y in Fig. 3a,b. Figure 3c shows that Ux/x increases with y. White arrows are included to indicate the direction of increasing gradient. Figure 3d shows that Uy/x decreases with x. Figure 3e shows that Ux/y increases with x, bearing in mind the direction of positive x depicted by the choice of axis in Fig. 2c. Figure 3f shows that Uy/y decreases with y. We used this knowledge to develop a model of the displacement field, with Utm(x,y)=Uxx+Uyy and Ux=Cxy and Uy=(−Dx2+Ex)+(−Fy2+Gy), where C=8×10−6, D=5×10−7, E=5×10−3, F=5×10−7, and G=1×10−2 are all constants, and x and yare unit vectors in the respective x and y directions as dictated by the coordinate axis in Fig. 2c. We applied this displacement field to the pristine (28,0) SWNT structure to generate the strained system, shown in Fig. 3g for Ux and Fig. 3h for Uy. These figures show that this model of displacement field produces a new strained (28,0) SWNT that has similar positions of atomic columns to the experimental image in Fig. 3a,b. Figure 3i–l show the 2D maps of Ux/x, Uy/x, Ux/y, and Uy/y respectively from Ux and Uy in Fig. 3g,h. Figure 3i shows Ux/x increases with y, as in the case of the experimental data in Fig. 3c. Figure 3j shows Uy/x decreases with x, as in Fig. 3d. Figure 3k shows Ux/y increases with x, as in Fig. 3e. Figure 3l shows Uy/y decreases with y, as in Fig. 3f. Thus, our model is a good description of the 2D displacement field, as it generates strain in a (28,0) SWNT that matches the experimental data.

For the model displacement field, Utm, the symmetric linearized strain matrix,  S, is

The anti-symmetric component, ɛ2, is non-zero and thus a rotation is present and described by:

The ɛ2 matrix is non-zero, which means that the shear is termed as simple rather than pure31. Furthermore, the non-zero components of the rotation matrix vary linearly with x, which confirms the non-uniform shear distribution varies along the axis of the SWNT.

Figure 3 shows strong evidence of non-uniform shear strain that varies along the axis of the SWNT. The GPA method of Hytch et al. 26 was also used to evaluate strain in the SWNT and also revealed non-uniform shear that varies along the SWNT axis (see Supplementary Information for further details). To understand the origins of this shear we present atomic model representations in Fig. 4 of several key types of strain. Torsional strain has been omitted as it was not observed. Figure 4a,b shows the unperturbed (28,0) SWNT with the 90° angle of the zig-zag section relative to the wall of the SWNT indicated at both the left and right ends. Figure 4c illustrates a uniform shear strain applied parallel to the axis of the SWNT, with the arrow indicating the direction. The zig-zag section is now at an angle of 97° relative to the sidewall. Figure 4d shows a uniform shear strain applied perpendicular to the SWNT axis, with the arrow indicating the direction. Figure 4d can be rotated to yield the exact same structure as Fig. 4c, indicative of the indistinguishable nature of uniform shear strain. Figure 4e shows a non-uniform shear strain applied parallel to the SWNT axis, which increases in magnitude from left to right, indicated by the arrow. This results in an increase in angle of the zig-zag section with respect to the SWNT sidewall. Figure 4f shows similar non-uniform shear strain (increasing from left to right), but this time applied perpendicular to the SWNT axis. The magnitude of the angle of the zig-zag section with respect to the SWNT sidewall increases with increasing shear strain. This results in bending of the SWNT, unlike the case in Fig. 4e. This enables the important distinction between non-uniform shear in SWNTs that arises from a force applied either parallel or perpendicular to the SWNT axis. Non-uniform shear perpendicular to the axis always gives rise to bending, unless a rotation that varies along the axis of the SWNT is included, whereas parallel non-uniform shear does not induce bending. Figure 4g shows pure geometrical bending (that is Euler beam bending). In this case the zig-zag section always remains at 90° with respect to the sidewall of the SWNT. Figure 4h shows a combination of geometrical bending with uniform shear strain (that is Timoshenko beam bending). The addition of uniform shear strain results in the angle of the zig-zag section deviating from 90°. The angle of deviation remains constant across the SWNT because of the uniform shear applied. A more complicated scenario can also arise, where geometrical bending is combined with non-uniform shear strain. This will result in variation of the angle of the zig-zag section with respect to the SWNT sidewalls.

Figure 4: Atomic model representations of several relevant key strain types applied to a (28,0) SWNT.
Atomic model representations of several relevant key strain types applied to a (28,0) SWNT.

a,b, No strain applied. c, Uniform shear applied parallel to axis. d, Uniform shear applied perpendicular to axis. e, Non-uniform shear applied parallel to axis. f, Non-uniform shear applied perpendicular to axis. g, Geometric bending (Euler beam bending). h, Geometric bending plus uniform shear (Timoshenko beam bending).

From the results obtained from Figs 13 and the models in Fig. 4, we can rule out pure geometrical bending as the source of shear strain in the experimental image. Furthermore, the magnitude of the observed shear strain is non-uniform and thus rules out the models in Fig. 4c,d,h. This leaves the possibilities of geometrical bending plus non-uniform shear, or just non-uniform shear strain. The bending induced by the non-uniform shear shown in Fig. 4f is in the same direction as observed in Fig. 1c. However, in Fig. 1c, the magnitude of the shear strain increases from right to left, whereas in Fig. 4f the magnitude of the shear strain is opposite and decreases from right to left. Thus, it is likely that the form of shear strain observed in Fig. 1c is due to a non-uniform shear strain arising from a traction applied parallel to the SWNT axis, with a distribution in magnitude that varies perpendicular to the axis across the 2.1 nm diameter. This non-uniform shear also involves variation in the C–C bond length across the region. The strain is distributed across a large region in the top section of the SWNT and the amount each bond deforms is small. To achieve such a strain and distortion as observed in Fig. 1c, a 1.6% increase in the C–C bond length over a 5 nm distance is required, corresponding to a change in bond length from ~1.42 Å to ~1.443 Å. Such small changes in the C–C bond length can be discerned only over the larger distance scales, where it has a cumulative effect on the position of atomic columns. The values of C–C bond stretching reported here of ~1.6% are less than those of ~3% reported by Huang et al. for elastically strained graphene nanoribbons (where C–C increases from ~1.429 Å to 1.474 Å with an applied force of ~5 N m−1; ref. 32). Applying a strain to a carbon nanotube is expected to yield some change in the C–C bond length33 and the magnitude of bond stretching observed here means that the (28,0) SWNT is likely to still be within the elastic regime. Variation in bond angles may also be expected in the strained bent SWNT, but the magnitude of bond angle change was too small to be accurately assessed. This may be an attribute of the zig-zag nature of the SWNT and the situation could change for chiral SWNTs that have inherent twists of the graphitic lattice.

These results directly confirm that SWNTs behave as Timoshenko beams, that is shear strain occurs during flexure. The nature of the shear observed is surprising as it requires variations in traction along the length of the SWNT. As there is no sign of an immediate source of such a force distribution in the local region, it may point towards the more complex non-local strain model as being relevant in the description of the deformation of SWNTs in the elastic regime6. The results presented here are not intended to be representative of all SWNTs, as the local strain induced on each SWNT will be different and vary substantially for each situation. By comparing our ultra-high resolution images of the (28,0) SWNT obtained by HRTEM with the simulated images from a perfect crystal we have been able to produce the first 2D displacement maps of strain in SWNTs and reveal the remarkable deformation mechanics of the SWNT. This methodology will enable bond-by-bond characterization of strain in nanomechanical systems.

http://www.nature.com/nmat/journal/

v10/n12/pdf/nmat3125.pdf?WT.ec_id=NMAT-201112

http://groupspaces.com/EntrepreneurshipOBN/e/204507?s=feac234f&utm_medium=email&utm_source=group-mail&utm_term=group-mail-4483

All document submission will be considered final.

1. Executive Summary

General description of the business problem, solution, business model used, and overall opportunity.

2. Problem

Specific description of the problem that the business plan intends to fix. Be specific about who is impacted by the problem.

3. Solution

Specific details of the proposed solution to the problem.

 

4. Business Model

Description of how the solution will be implemented and create value, including long-term strategy.

 

5. Unique factor / innovation

Description of what makes the idea unique, and how will this uniqueness be protected from imitators.

 

6. Competition

Description of the main competitors in the market space or industry. How will your plan accommodate for competitors and rivalry.

 

7. Marketing and Sales

Description of how the business will be brought to market.  What methods will be used to promote the idea and what markets will be targeted?

8. Management team

Description of your team, partners and collaborators.  How is the team structured and what are the skills needed to be successful.

 

9. Financial projections and key metrics

Comprehensive financial analysis of your business plan, including costs, sources of investment, revenue projections, etc.

10. Current status, accomplishments to date, timeline and use of funds

Description of current status of plan development, overall timeframe for the business idea, and how financing will be allocated over the development lifecycle.

This article was written by Roland J. Meerdter, Founder and Managing Director of Propinquity Advisors.  Roland will be speaking at FundForum Asia 2012 and FundForum International 2012 

Whose Client is it Anyway?

Larry Fink is advising investors in general and his clients in particular to own 100% equities.  Clearly the man who was instrumental in building a 3.3 trillion dollar asset manager on the foundation of bonds has become a stock guy.  Whether or not this radical asset shift is sensible is certainly debatable.  But an equally interesting question  for many of us thinking through the quickly evolving nature of asset management and distribution is:

“who, exactly, are Larry’s clients?”

and, what does he know about asset allocation?  Is Jan Investor, ABC Pension Fund and XYZ Foundation BlackRock’s client or that of the investment intermediary who, so graciously, made the allocation to BlackRock’s investment strategy?

Certainly the intermediaries through whom  BlackRock and every other asset manager around the globe have gathered assets (investment consultants, private banks, broker-dealers and the like) see the situation differently.  They are not in a position to take Larry’s advice and move their clients into 100% equities.  In fact, they are not interested in BlackRock’s (or any other manager for that matter) opinions on asset allocation at all.  In fact, they are the ones giving asset allocation advice and getting paid for it.  Without the advice, what are they good for?  Are they simply an introduction service for fee-hungry asset managers with 40% (+/-) margins?   How are they going to earn their fees and maintain themselves in the relationship?  Ah, there’s the rub.

These intermediaries, at least in how they are used to operating, do not want Larry’s advice and asset allocation acumen – they want him to ensure that the fixed income products outperform their peers and benchmarks, that the hedge funds produce absolute returns, that the style of the equity products don’t drift…get my drift? Stay in the box Larry, we’ll let you know when we need you.

Please click this link to continue reading the full article at www.propinquityadvisors.com

To find out more about our FundForum events, click here for FundForum Asia, or here for information on FundForum International.

0 Comments – Leave a comment!

New Insights Into The US Fund Industry Trends

Written on February 6, 2012 by in Asset Management, Events, Fund Selection, Uncategorized

The Latest Research From FundForum USA 2012  The world is in flux for the asset manager’s and 2012 may be the year that the industry will wake up to this change.   All in all, mutual funds have been a remarkably resilient business and the competition coming from ETFs, alternative products and other investment vehicles…

Continue Reading »

0 Comments – Leave a comment!

FundForum International 2012 Research Trends

Each year, the FundForum International programme is extensively researched afresh.  The programme director, Jenny Adams, not only speaks to over 100 senior players from our asset management and fund selectors/ advisors community about their views and concerns for the coming year, but covers all sectors from CEOs and CIOs to distribution, product development and marketing in…

Continue Reading »

0 Comments – Leave a comment!

Looking Ahead to FundForum Asia 2012

Written on January 19, 2012 by in Asset Management, Events, Uncategorized

After a very successful 2011 for all our FundForum events, we now look ahead to the new year, with the focus now on the 23rd April for FundForum Asia 2012 in Hong Kong.  Sarah Armstrong, Conference Director for FundForum Asia, gives us a snapshot of what to expect in 2012. What Are The Big Industry…

Continue Reading »

0 Comments – Leave a comment!

The FundForum 2011 Annual Roundup

Written on January 6, 2012 by in Events, Uncategorized

It has been a very busy, successful and innovative year for FundForum International. Jenny Adams, Programme Director for FundForum International and Head of Innovation for ICBI looks back at 2011 and gives some clear pointers for what you can expect to see in 2012. What have been the key Fund Management topics discussed this year?…

Continue Reading »

0 Comments – Leave a comment!

FundForum Best Ideas Breakfast Club Discusses Market Volatility

Written on December 15, 2011 by in Asset Management, Business Effectiveness, Events, Fund Selection

By Kalpana Fitzpatrick   Quality research and diversification of assets will be the utmost important element for fund managers if they are to survive ongoing market volatility over the couple of years. In an exclusive filming, part of the FundForum series – known as the CEO Best Ideas Breakfast Club – Antony John, CEO, Fund…

Continue Reading »

0 Comments – Leave a comment!

HSBC chief argues the case for emerging markets

Written on November 7, 2011 by in Events

By Kalpana Fitzpatrick Fund managers should start thinking of emerging markets as mainstream and not the niche, according to the chief executive of HSBC Global Asset Management at FundForum USA. John Flint, whose firm has a strong footprint in the region, said the change in attitude would help fund managers become more successful in the…
I did not mention that it was the Ides of March today; indeed, the sole reason is that I forgot.  I have since been trying to work out how we could have winkled it in.  Not much of the Ides of March about Vitruvius.  Yet Shakespeare was haunting the first part of the programme when Serafina did her rapid rundown of the 1st century BC.  You wanted to keep saying “wasn’t that bit in Shakespeare?” or “where’s Brutus?”

It is quite a career for someone to start making ballistic missiles and catapults for Caesar’s army in Gaul, and end up sitting in Rome as an aged protégé of the Emperor’s sister, writing a very substantial book on the history of architecture.  Those lives which travel so far from their beginnings are always fascinating.  And I’m becoming increasingly fascinated with people who really start at the coalface quite young and manage to work their way through to enormous achievements.  Nelson joined the Navy when he was twelve.  A lot of the men who created the Industrial Revolution were apprenticed or chucked into jobs when they were thirteen or fourteen.  And so it goes…

The thing that struck me this morning was how very, very powerful knowledge is and how you never know when it will be rediscovered and re-energised.  We’re used to it in science now.  Rutherford splits the atom and says no harm will come of it, but it was an intellectually satisfying thing to do, and a few years later the world could be blown up.  And again and again, as we are finding, games that mathematicians play with prime numbers, for example, turn out to be the way in which we run crucial parts of the communications system.  Sometimes these developments take hundreds of years.  Much the same here with Vitruvius.  He
petered out when Rome petered out and St Peter’s Rome took over.  His temples were no longer required in an age of churches and cathedrals.  The fascinating thing is that the Renaissance in Italy went pagan.  Palladio’s churches are built precisely like temples.  There is very little about the atmosphere inside them which echoes, even – let alone matches – the heavy, religious splendours of cathedrals, or the simple, religious peace of village churches.  These are places which have abandoned a medieval God and are open, it seems, to all influences.

Got up this morning at about five and found a Dickensian fog outside and freezing weather.  In the middle of the day people are sunbathing in London parks.  London itself is so crowded that you wonder if this is a secret trial run for the congestion of the Olympics.  At the moment much of central London is dug up in order to make it spick and span for the Olympics.  Those of us who live here have our doubts…

http://view6.workcast.net/?pak=5103484536326804&cpak=2276376745166157

http://www.fields.utoronto.ca/programs/scientific/12-13/summer-research12/

http://www.fields.utoronto.ca/programs/scientific/11-12/COSY2012/

http://www.fields.utoronto.ca/programs/scientific/11-12/topology/

http://www.fields.utoronto.ca/programs/scientific/11-12/inverseprob/

‘Scattering rigidity with trapped geodesics; the two dimensional case
http://www.fields.utoronto.ca/programs/scientific/11-12/inverseprob/geometry/

http://www.fields.utoronto.ca/programs/scientific/11-12/graphicmodels/

http://www.fields.utoronto.ca/programs/scientific/11-12/IDEA/

Apr 23-27, 2012
WORKSHOP ON THE P-ADIC LANGLANDS PROGRAM: RECENT DEVELOPMENTS AND
APPLICATIONS
http://www.fields.utoronto.ca/programs/scientific/11-12/galoisrep/wksp_p-adic/

Apr 25, 2012 — 5:00 p.m.
QUANTITATIVE FINANCE SEMINAR
Steve Shreve (Carnegie Mellon)
‘Optimal Execution in a General One-Sided Limit Order Book’
and
Rogemar Mamon (Western)
http://www.fields.utoronto.ca/programs/cim/11-12/finance_seminar/

Starting Apr 30-May 31, 2012
SHORT COURSES ON VARIATIONAL METHODS AND COMPRESSIVE SENSING IN IMAGING
1.Sparse Signal Processing and Compressive Sensing
Richard Baraniuk (Rice)
2.Geodesic Methods in Image Analysis
Laurent Cohen(Paris-Dauphine)
3.Partial Differential Equation Methods in Image Processing
Selim Esedoglu (Michigan)
4.Numerical Methods for Sparse Recovery
Massimo Fornasier (Johann Radon Institute)
5.Numerical Geometry of Images
Ron Kimmel (Technion)
http://www.fields.utoronto.ca/programs/scientific/11-12/inverseprob/sensing/

May 7, 2012 –3:30 p.m.
DISTINGUISHED LECTURE SERIES
Emmanuel Candes (Stanford University)
May 7 — 3:30 p.m. Bahen Centre, BA1130
‘From compressive sensing to super-resolution’
May 8 — 3:30 Fields Institute, Room 230
‘Robust principal component analysis?
Some theory and some applications’
May 9 — 2:00 p.m. Fields Institute, Room 230
‘PhaseLift: Exact Phase Retrieval via Convex Programming’
http://www.fields.utoronto.ca/programs/scientific/11-12/inverseprob/DLS/

May 14-18, 2012
MATHEMATICAL NEUROSCIENCE AND NEUROBIOLOGY INTRODUCTORY COURSES
Instructors:
David Terman (Mathematics, Ohio State)
Martin Wojtowicz (Physiology, Toronto)
Melanie Woodin (Cell & Systems Biology, Toronto)
Sue Ann Campbell (Applied Mathematics, Waterloo)
Frances Skinner (Toronto Western Research Institute)
Katie Ferguson (Toronto Western Research Institute)
http://www.fields.utoronto.ca/programs/scientific/11-12/neurodisease/tutorials/

May 22-23, 2012
PARKINSON’S DISEASE WORKSHOP
Registration required
http://www.fields.utoronto.ca/programs/scientific/11-12/neurodisease/parkinson/

May 24-25, 2012
SCHIZOPHRENIA WORKSHOP
Registration required
http://www.fields.utoronto.ca/programs/scientific/11-
12/neurodisease/schizophrenia/

May 29-30, 2012
EPILEPSY WORKSHOP
Registration required
http://www.fields.utoronto.ca/programs/scientific/11-12/neurodisease/epilepsy/

May 31-Jun 1, 2012
ALZHEIMER’S DISEASE/PHARMACEUTICALS WORKSHOP
Registration required
http://www.fields.utoronto.ca/programs/scientific/11-12/neurodisease/alzheimer/

For upcoming activities in December and the ongoing scientific seminars,
see the Fields Calendar of Events at: http://www.fields.utoronto.ca/programs

==================
FIELDS SUPPORTED ACTIVITIES AT OUR PARTNER UNIVERSITIES
==================
April 11-13, 2012
Workshop on Recent Progress in Quantum Algorithms
to be held at the University of Waterloo and the Perimeter Institute
http://qa2012.iqc.uwaterloo.ca/home/welcome.phtml

Apr 19-22, 2012
Workshop on Exceptional Algebras and Groups
University of Ottawa
http://www.fields.utoronto.ca/programs/scientific/11-12/exceptional/

Apr 26 -27
Fields-Carleton Distinguished Lecture Series
Carleton University
Speaker: Kenneth R. Davidson, University of Waterloo
http://www.fields.utoronto.ca/programs/scientific/11-12/Fields-Carleton/

Apr 29-May 2, 2012
Canadian Human and Statistical Genetics Meeting
White Oaks Conference Centre, Niagara-on-the-Lake
http://epigen1.mcgill-cihr-ig.ca/

May 5-8, 2012
GAP 2012 (Geometry And Physics) Conference
University of Waterloo and the Perimeter Institute for Theoretical Physics
http://www.math.uwaterloo.ca/~gap/

May 14-19, 2012
Workshop on Recent Advances in General Topology, Dimension Theory,
Continuum Theory and Dynamical Systems
Nipissing University
http://www.fields.utoronto.ca/programs/scientific/11-12/topology/

May 21, 2012
Canadian Operator Symposium, 2012
Queen’s University
http://www.mast.queensu.ca/~cosy2012/

May 29-31, 2012
Workshop on Rational Homotopy Theory and its Applications
University of Ottawa
http://www.fields.utoronto.ca/programs/scientific/11-12/homotopy2012/

May 30-Jun 1, 2012
Symposium on the Analysis of Survey Data and Small Area Estimation
Carleton University
http://www.fields.utoronto.ca/programs/scientific/11-12/surveydata/

labmate online

http://lm.targetmailer.co.uk/get/template/html/86/ccb180a97b85678a205eaeb444e5ed7b/85/126965/0/65f91ccc0c976f149467ef11634df946

http://www.workopolis.com/EN/Common/SearchJobs.aspx?DisplayMode=New

 

http://www.linkedin.com/groupItem?trk=eml-anet_dig-b_pd-pmr-cn&gid=1808582&view=&ut=2UM8dwJjFkalc1&commentID=75415994&item=105369200&type=member

http://www.princes-foundation.org/content/making-princes-houses-available-everyone

2 Comments

Filed under Uncategorized

…….it being forbidden up to 10 years for any other person in any territory of ours to make a contrivance in the form and resemblance therefore….

Persecution of noted physicians and medical scientists

http://www.annclinlabsci.org/content/37/3/295.full

Most high school graduates are familiar with the trial and conviction of the Italian astronomer and physicist, Galileo (1564–1642), in 1633 for publishing a treatise on his observation that the earth revolves around the sun. The Inquisition banned his writings and Galileo spent the remainder of his life under house arrest.

Similarly, many mathematicians know that the Greek mathematician and philosopher, Pythagoras (582–500 BC), was kidnapped from Egypt by the invading Persians and imprisoned in Persia (present day Iran). But few physicians are aware that some of the most illustrious medical scientists and physicians have been persecuted and even executed or murdered for their professional, religious, or political beliefs. In this review, 12 appalling stories are recounted.

Rhazes (860–932 AD) devoted most of his efforts as a physician to the practice of surgery and to teaching at the medical school in Baghdad. He introduced the works of Hippocrates and Galen to the Arabic world. His “western” teachings, rational thinking, and fame as a medical writer and practicing physician brought Rhazes into conflict with the local hierarchy. He lost his teaching position, he was arrested, and his books were outlawed. His torturers hit his head with his books until he was blind. He died in extreme poverty [1].

Abumeron Avenzoar (1093–1162) of Cordova was the greatest Spanish Moslem physician and thinker. Because he and his pupils dared to express opinions contrary to Galen, a favorite of every organized religion, and because they promulgated doctrines of a self-renewing world (emergent evolution and virtual denial of creation), Avenzoar was persecuted and forbidden to write or teach. In his later years he earned his living by manual labor [2].

Guido Lanfranchi (1252–1315), also known as Lanfranc, was an Italian physician and surgeon who initially practiced in Milan. He was persecuted for political reasons and ultimately was driven out of Italy. He sought asylum in France and settled in Paris in 1295. He rapidly became known as the best surgeon in France. His published texts and high position in surgical circles earned him his reputation as the founder of French surgery [3].

Andreas Vesalius (1514–1564) is remembered as a great anatomist and as a founder of modern medical science that is based on facts rather than traditions. He had a turbulent life. As a student he was expelled from the University of Louvain, Belgium. He sought temporary refuge in Paris and at last found his place in Padua, Italy. After his epoch-making work, the Fabrica, was published, his fame as an anatomist became greater with every passing year. After his name became known around the world he was appointed as a court physician in Spain. By dissecting the body of a Spanish nobleman who had died in his care, Vesalius found, when he opened the man’s chest, that the heart was still beating. He was accused of murder and was brought before the Inquisition. The King commuted Vesalius’s death sentence to a pilgrimage of penitence to the Holy Land. While on the passage back to Spain after his pilgrimage, he died in a shipwreck [4].

Michael Servetus (1511–1553), a Spanish physician, discovered in 1545 the lesser circulation (the pulmonary circulation). Because he wrote a book in which he included certain remarks on the reform of Christianity, the book was regarded as heretical. He escaped from Spain and the Catholic Inquisition, but in Switzerland the Protestant Inquisition caught up with him. By order of John Calvin, Servetus was arrested, tortured, and burned at the stake on the shores of Lake Geneva together with copies of his book [5].

Johann G. Wirsung (1600–1643), a Bavarian monk and physician, discovered the excretory duct of the pancreas in 1642. Wirsung was envied by University professors and was subjected to incessant verbal insults. Jealousy led to a quarrel at the conclusion of a meeting, and he was shot to death by an assistant physician [6].

Marcello Malpighi of Bologna (1628–1694) is remembered as a founding father of anatomic pathology because of his pioneering studies on the liver, kidney, and spleen. His investigations received favorable comments outside the borders of Italy but on his home turf Malpighi was subjected to vitriolic attacks by his fellow professors. On more than one occasion, Malpighi was threatened and physically assaulted by his enemies. Ultimately, his attackers burned down his house and destroyed his library [7].

Henry Oldenburg (1615–1677) was a founder and the first secretary of the Royal Society, which was chartered in London in 1662. He vigorously solicited first-rate scientific papers for publication in the Society’s journal. He was instrumental in publishing many writings by the Dutch scientists, Leeuwenhoek and Swammerdan, as well as by the Italian, Malpighi. Oldenburg’s frequent and voluminous correspondence with foreigners attracted the attention of the authorities and he was arrested as a spy. He was jailed in the Tower of London for several months. Ultimately, he was released after Royal intercession [8].

Antoine-Laurent Lavoisier (1743–1794), a pioneer French respiratory physiologist, became a leading member in the pre-revolutionary French Academy of Science after his discovery that oxygen in inspired air is converted to carbon dioxide. Lavoisier opposed the election of Jean-Paul Marat to membership in the Academy. Years later, when Marat was a prominent leader of the French Revolution, he remembered Lavoisier. Lavoisier was arrested on trumped-up charges of financial irregularities and was tried by a revolutionary tribunal chaired by Marat. Lavoisier was guillotined on the day his trial ended and his body was buried in an unmarked grave [9].

James Wardrop (1782–1869), a prominent Edinburgh surgeon, is renowned for his aggressive operative procedures and for his introduction of the term “soft cancer” (soft tissue sarcoma). He learned about soft cancers in Vienna, Austria, having fled from France in 1803, when Napoleon ordered that English residents in France be arrested and imprisoned [10].

Rudolph Virchow (1821–1902), the most celebrated German pathologist, was throughout his life an outspoken champion of social and democratic reforms. In 1848, when he was an assistant pathologist, Virchow was a leader of an armed revolution in Berlin, demanding constitutional government, freedom of the press, and universal healthcare. The short-lived revolution failed. Virchow lost his job, was investigated by the police, and was banished from Berlin. To avoid formal prosecution and imprisonment, Virchow went to Würzburg in Bavaria, where he found an academic position, but had to promise that he would stay out of politics. He kept his pledge, but upon his return to Berlin in 1858, Virchow resumed his political activities and was elected a member of the German Reichstag [11].

Gerhard Domagk (1895–1964) was awarded the Nobel Prize in Medicine in 1939 for his 1935 discovery of the antibacterial effect of sulphonamide. Domagk was officially notified by the Nobel Committee in November 1939 (two months after the Second World War began) that he would receive the Prize. He instantly wrote a letter to the chairman of the Nobel Committee and expressed his thanks for the honor. Two weeks after he mailed the letter to Stockholm, he was arrested by the German secret police and taken to Gestapo headquarters. During his interrogation and incarceration he refused to eat. After his release, a week later, he was forced to sign a prepared letter that, because he was a loyal German citizen, he was not accepting the Nobel Prize, since by law Germans could not accept such awards or recognition from foreign nations.

During the Second World War, Domagk and his family were constantly watched by the police and occasionally he was brought to the police headquarters for questioning. Despite the fact that he was not permitted any contact with foreigners, sulphonamide was introduced in the late 1930s in many countries as an antibacterial drug. In Germany, however, Domagk and sulphonamide remained black-listed until the end of the war in 1945. The epilogue to Domagk’s story is that in 1947 he was invited to attend the Nobel celebration in Stockholm. He received the tokens of his 1939 prize, the diploma and the gold medal, but no Prize money. This was because in his will Alfred Nobel prohibited distribution of money if the Prize remained unclaimed beyond 10 months [12].

The preceding tally of individual tragedies of noted physicians and medical scientists is far from complete. As time and space permit, additional narratives will be presented.

  1. Riesman D. The Story of Medicine in the Middle Ages. Hoebner, New York, 1935.
  2. Garrison FH. An Introduction to the History of Medicine. Saunders, Philadelphia, 1929.
  3. Singerist HE. The historical development of the pathology and therapy of cancer. Bull NY Acad Med 1932;8:642–653.
  4. Castiglioni A. Histoire de la Médecine. Payot, Paris, 1931.
  5. Christie RV. Discovery of the pulmonary circulation. Dis Chest 1969;56:409–411.
  6. Wood M. Eponyms in biliary tract surgery. Amer J Surg 1979;138:746–754.
  7. Scarani P, Salvioli GP, Eusebi V. Marcello Malpighi (1628–1694). Amer J Surg Path 1994;18:741–746.
  8. Dobell C. Antony van Leeuwenhoek and His Little Animals. Russell and Russell, New York, 1958.
  9. Moll JMH. Antoine-Laurent Lavoisier. J Med Biogr 1994:2;242.
  10. Ewing J. Neoplastic Diseases. Saunders, Philadelphia, 1919.
  11. Rabl M. Rudolf Virchow, Briefe an seine Eltern 1839–1864. Engelmann, Leipzig, 1907.
  12. Schück H. Sohlman R, Österling A. et al. Nobel, The Man and His Prizes. Elsevier, Amsterdam, 1962.

ELECTROMAGNETIC SPECTRUM

The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation.[1] The “electromagnetic spectrum” of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object.

The electromagnetic spectrum extends from low frequencies used for modern radio communication to gamma radiation at the short-wavelength (high-frequency) end, thereby covering wavelengths from thousands of kilometers down to a fraction of the size of an atom. It is for this reason that the electromagnetic spectrum is highly studied for spectroscopic purposes to characterize matter.[2] The limit for long wavelength is the size of the universe itself, while it is thought that the short wavelength limit is in the vicinity of the Planck length,[3] although in principle the spectrum is infinite and continuous.

HISTORY

or most of history, light was the only known part of the electromagnetic spectrum. The ancient Greeks recognized that light traveled in straight lines and studied some of the properties of it, including reflection and refraction. Over the years the study of light continued and during the 16th and 17th centuries there were conflicting theories which regarded light as either a wave or a particle. It was first linked to electromagnetism in 1845 when Michael Faraday noticed that light responded to a magnetic field. The first discovery of electromagnetic waves other than light came in 1800, when William Herschel discovered infrared light. He was studying the temperature of different colors by moving a thermometer through light split by a prism. He noticed that the hottest temperature was beyond red. He theorized that there was ‘light’ that you could not see. The next year, Johann Ritter worked at the other end of the spectrum and noticed that there were ‘chemical rays’ that behaved similar to, but were beyond, visible violet light rays. They were later renamed ultraviolet radiation. During the 1860s James Maxwell was studying electromagnetic field and realized that they traveled at around the speed of light. He developed four partial differential equations to explain this correlation. These equations predicted many frequencies of electromagnetic waves traveling at the speed of light. Attempting to prove Maxwell’s equations, in 1886 Heinrich Hertz built an apparatus to generate and detect radio waves. He was able to observe that they traveled at the speed of light and could be both reflected and refracted. In a later experiment he similarly produced and measured microwaves. These new waves paved the way for inventions such as the wireless telegraph and the radio. In 1895 Wilhelm Röntgen noticed a new type of radiation emitted during an experiment. He called these x-rays and found they were able to travel through parts of the human body but were reflected by denser matter such as bones. Before long many uses were found for them in the field of medicine. The last portion of the electromagnetic spectrum was filled in with the discovery of gamma rays. In 1900 Paul Villardwas studying radioactivity. He first thought they were particles similar to alpha and beta particles. However, in 1910 Ernest Rutherford measured their wavelengths and found that they were electromagnetic waves.

[edit] Range of the spectrum

Electromagnetic waves are typically described by any of the following three physical properties: the frequency f, wavelength λ, or photon energy E. Frequencies range from 2.4×1023 Hz (1 GeV gamma rays) down to the local plasma frequency of the ionized interstellar medium (~1 kHz). Wavelength is inversely proportional to the wave frequency,[2] so gamma rays have very short wavelengths that are fractions of the size of atoms, whereas wavelengths can be as long as the universe. Photon energy is directly proportional to the wave frequency, so gamma rays have the highest energy (around a billion electron volts) and radio waves have very low energy (around a femtoelectronvolt). These relations are illustrated by the following equations:

f = \frac{c}{\lambda}, \quad\text{or}\quad f = \frac{E}{h}, \quad\text{or}\quad E=\frac{hc}{\lambda},

where:

Whenever electromagnetic waves exist in a medium with matter, their wavelength is decreased. Wavelengths of electromagnetic radiation, no matter what medium they are traveling through, are usually quoted in terms of the vacuum wavelength, although this is not always explicitly stated.

Generally, electromagnetic radiation is classified by wavelength into radio wave, microwave, terahertz (or sub-millimeter) radiation, infrared, the visible region we perceive as light, ultraviolet, X-rays and gamma rays. The behavior of EM radiation depends on its wavelength. When EM radiation interacts with single atoms and molecules, its behavior also depends on the amount of energy per quantum (photon) it carries.

Spectroscopy can detect a much wider region of the EM spectrum than the visible range of 400 nm to 700 nm. A common laboratory spectroscope can detect wavelengths from 2 nm to 2500 nm. Detailed information about the physical properties of objects, gases, or even stars can be obtained from this type of device. Spectroscopes are widely used in astrophysics. For example, many hydrogen atoms emit a radio wave photon that has a wavelength of 21.12 cm. Also, frequencies of 30 Hz and below can be produced by and are important in the study of certain stellar nebulae[8] and frequencies as high as 2.9×1027 Hz have been detected from astrophysical sources.[9]

[edit] Rationale

Electromagnetic radiation interacts with matter in different ways in different parts of the spectrum. The types of interaction can be so different that it seems to be justified to refer to different types of radiation. At the same time, there is a continuum containing all these “different kinds” of electromagnetic radiation. Thus we refer to a spectrum, but divide it up based on the different interactions with matter.

http://en.wikipedia.org/wiki/Electromagnetic_spectrum

  1. ^ “Imagine the Universe! Dictionary”. http://imagine.gsfc.nasa.gov/docs/dict_ei.html#em_spectrum.
  2. ^ a b c d e Mehta, Akul. “Introduction to the Electromagnetic Spectrum and Spectroscopy”. Pharmaxchange.info. http://pharmaxchange.info/press/2011/08/introduction-to-the-electromagnetic-spectrum-and-spectroscopy/. Retrieved 2011-11-08.
  3. ^ U. A. Bakshi, A. P. Godse (2009). Basic Electronics Engineering. Technical Publications. pp. 8–10. ISBN 978-81-8431-580-6. http://books.google.com/books?id=n0RMHUQUUY4C. Retrieved 2011-10-16.
  4. ^ What is Light?UC Davis lecture slides
  5. ^ Glenn Elert. “The Electromagnetic Spectrum, The Physics Hypertextbook”. Hypertextbook.com. http://hypertextbook.com/physics/electricity/em-spectrum/. Retrieved 2010-10-16.
  6. ^ “Definition of frequency bands on”. Vlf.it. http://www.vlf.it/frequency/bands.html. Retrieved 2010-10-16.
  7. ^ Mohr, Peter J.; Taylor, Barry N.; Newell, David B. (2008). “CODATA Recommended Values of the Fundamental Physical Constants: 2006”. Rev. Mod. Phys. 80 (2): 633–730. Bibcode 2008RvMP…80..633M. DOI:10.1103/RevModPhys.80.633. http://physics.nist.gov/cuu/Constants/index.htmlDirect link to value.
  8. ^ J. J. Condon and S. M. Ransom. “Essential Radio Astronomy: Pulsar Properties”. National Radio Astronomy Observatory. http://www.cv.nrao.edu/course/astr534/Pulsars.html. Retrieved 2008-01-05.
  9. ^ A. A. Abdo et al. (2007). “Discovery of TeV Gamma-Ray Emission from the Cygnus Region of the Galaxy”. The Astrophysical Journal Letters 658: L33. arXiv:astro-ph/0611691. Bibcode 2007ApJ…658L..33A. DOI:10.1086/513696.
  10. ^ Feynman, Richard; Robert Leighton, Matthew Sands (1963). The Feynman Lectures on Physics, Vol.1. USA: Addison-Wesley. pp. 2–5. ISBN 0-201-02116-1.
  11. ^ L’Annunziata, Michael; Mohammad Baradei (2003). Handbook of Radioactivity Analysis. Academic Press. p. 58. ISBN 0-12-436603-1. http://books.google.com/?id=b519e10OPT0C&pg=PA58&dq=gamma+x-ray.
  12. ^ Grupen, Claus; G. Cowan, S. D. Eidelman, T. Stroh (2005). Astroparticle Physics. Springer. p. 109. ISBN 3-540-25312-2.
  13. ^ Corrections to muonic X-rays and a possible proton halo slac-pub-0335 (1967)
  14. ^ “Hyperphysics (see Gamma-Rays”. Hyperphysics.phy-astr.gsu.edu. http://hyperphysics.phy-astr.gsu.edu/hbase/ems3.html#c5. Retrieved 2010-10-16.
  15. ^ “Advanced weapon systems using lethal Short-pulse terahertz radiation from high-intensity-laser-produced plasmas”. India Daily. March 6, 2005. http://www.indiadaily.com/editorial/1803.asp. Retrieved 2010-09-27.
  16. google-site-verification: googlec879ff6879672e67.html
  17. [googlec879ff6879672e67.html]

Leave a comment

Filed under Uncategorized