Plasmonic gratings with nano-protrusions made by glancing angle deposition for single-molecule super-resolution imaging.

Super-resolution imaging has been advantageous in studying biological and chemical systems, but the required equipment and platforms are expensive and unable to observe single-molecules at the high (µM) fluorophore concentrations required to study protein interaction and enzymatic activity. Here, a plasmonic platform was designed that utilized an inexpensively fabricated plasmonic grating in combination with a scalable glancing angle deposition (GLAD) technique using physical vapor deposition. The GLAD creates an abundance of plasmonic nano-protrusion probes that combine the surface plasmon resonance (SPR) from the periodic gratings with the localized SPR of these nano-protrusions. The resulting platform enables simultaneous imaging of a large area without point-by-point scanning or bulk averaging for the detection of single Cyanine-5 molecules in dye concentrations ranging from 50 pM to 10 µM using epifluorescence microscopy. Combining the near-field plasmonic nano-protrusion probes and super-resolution technique using localization microscopy, we demonstrate the ability to resolve grain sizes down to 65 nm. This plasmonic GLAD grating is a cost-effective super-resolution imaging substrate with potential applications in high-speed biomedical imaging over a wide range of fluorescent concentrations.

Origin of Perpendicular Magnetic Anisotropy and Large Orbital Moment in Fe Atoms on MgO.

We report on the magnetic properties of individual Fe atoms deposited on MgO(100) thin films probed by x-ray magnetic circular dichroism and scanning tunneling spectroscopy. We show that the Fe atoms have strong perpendicular magnetic anisotropy with a zero-field splitting of 14.0±0.3 meV/atom. This is a factor of 10 larger than the interface anisotropy of epitaxial Fe layers on MgO and the largest value reported for Fe atoms adsorbed on surfaces. The interplay between the ligand field at the O adsorption sites and spin-orbit coupling is analyzed by density functional theory and multiplet calculations, providing a comprehensive model of the magnetic properties of Fe atoms in a low-symmetry bonding environment.

An integrative approach for evaluating work related musculoskeletal disorders.

OBJECTIVES: To develop a framework for evaluating the work related musculoskeletal disorders (WRMSDs). PARTICIPANTS: The proposed framework was tested on 15~jewellery manufacturing workers working at Chinchpokhli region in Mumbai, India and on 15 students studying in a management institute of Mumbai, India. METHODS: The framework has been broken into three phases. Phase 1--Ergonomic-risk evaluation; Phase 2--Musculoskeletal Disorders (MSD) evaluation and Phase 3--Clinical examination. Ergonomic-risk evaluation determines the relationship between work relatedness and musculoskeletal disorders. Musculoskeletal Disorders (MSD) evaluation tries to assess the presence of discomforts/disabilities in different body regions, through subjective evaluation tools. Ergonomic-risk evaluation involved QEC, PLIBEL and posture analysis by RULA. Musculoskeletal Disorders (MSD) evaluation involved administration of self reported questionnaires. Clinical examination involved muscle grading by a physiotherapist and back strength measurement. RESULTS: The framework suggested that ergonomic risk evaluation techniques, self reported body part questionnaires and physical measurement of physiological/biomechanical transients may have a relationship and can be used for the evaluation of work related musculoskeletal disorders. CONCLUSION: The proposed integrative approach will help in developing stage wise intervention strategies for work related musculoskeletal disorders.

Fluorescence enhancement from nano-gap embedded plasmonic gratings by a novel fabrication technique with HD-DVD.

We demonstrate strong electromagnetic field enhancement from nano-gaps embedded in silver gratings for visible wavelengths. These structures fabricated using a store-bought HD-DVD worth $10 and conventional micro-contact printing techniques have shown maximum fluorescence enhancement factors of up to 118 times when compared to a glass substrate under epi-fluorescent conditions. The novel fabrication procedure provides for the development of a cost-effective and facile plasmonic substrate for low-level chemical and biological detection. Electromagnetic field simulations were also performed that reveal the strong field confinement in the nano-gap region embedded in the silver grating, which is attributed to the combined effect of localized as well as propagating surface plasmons.

Imaging and manipulation of the Si(100) surface by small-amplitude NC-AFM at zero and very low applied bias.

We use a noncontact atomic force microscope in the qPlus configuration to investigate the structure and influence of defects on the Si(100) surface. By applying millivolt biases, simultaneous tunnel current data is acquired, providing information about the electronic properties of the surface at biases often inaccessible during conventional STM imaging, and highlighting the difference between the contrast observed in NC-AFM and tunnel current images. We also show how NC-AFM (in the absence of tunnel current) can be used to manipulate both the clean c(4 × 2) surface and dopant-related defects.

Counting Single Rhodamine 6G Dye Molecules in Organosilicate Nanoparticles.

Rhodamine 6G (R6G) dye molecules have been embedded into organosilicate nanoparticles to improve thermal and chemical stability of these marker molecules. We demonstrate that the well-established method of optical single-particle microscopy can be used to determine the number of dye molecules per nanoparticle in such hybrid materials. Analysing the fluorescence intensity of R6G in single nanoparticles, we obtain an average number of 1.3 - 1.7 dye molecules per nanoparticle as compared to 1 R6G per particle obtained from ensemble experiments. The blinking behaviour of embedded R6G can be described by a power law with an exponent α(on/off) = - 1.7. Ensemble measurements complete the optical characterization of the nanoparticles, which reveals no pronounced R6G aggregate formation.

Influence of stabilizers on quality of sandesh from buffalo milk.

Buffalo milk standardized to solids-not-fat (SNF) to fat ratio of 1.4 was added separately with 0.1% (w/w) each of carrageenan, sodium alginate and carboxymethyl cellulose and then heated, cooled and coagulated to obtain chhana which was converted into sandesh by adding 1.5% (w/w) wheat flour and 25% (w/w) cane sugar followed by heating (40 min/kg chhana). The treated samples of sandesh were compared with control prepared similarly manner but without stabilizer. Addition of stabilizer decreased hardness, fracturability, adhesiveness, cohesiveness, gumminess and chewiness of sandesh and improved sensory body and texture, colour and appearance as well as overall acceptability of the product when compared with control. Textural and sensory properties of different samples of sandesh indicated that the product made by adding carrageenan proved best. Carrageenan at 0.1% produced better results in terms of textural and sensory profile of sandesh as compared to 0, 0.075 and 0.125% (w/w) of carrageenan.

Randomised controlled trial evaluating the role of tirofiban in high-risk non-ST elevation acute coronary syndromes: an East Indian perspective.

INTRODUCTION: Glycoprotein IIb/IIIa inhibitors such as tirofiban inhibit platelet aggregation. We evaluated the immediate and early outcomes in patients with high-risk non-ST elevation acute coronary syndrome (NSTE ACS) who received tirofiban with conventional therapy compared to patients who received only conventional therapy (a combination of aspirin, clopidogrel, low-molecular-weight heparin with or without beta-blockers and angiotensin-converting enzyme inhibitors). METHODS: A total of 165 patients received conventional therapy with a placebo, and 136 patients received conventional therapy with tirofiban after randomisation. The outcomes were measured on Day 7, Day 14, one month and three months after the administration of therapy. RESULTS: A significant reduction was noted in the occurrence of primary endpoints in patients receiving tirofiban, compared to those who received a placebo at seven days (14 versus 32; p-value is 0.036), 14 days (14 versus 28; p-value is 0.043), one month (19 versus 34; p-value is 0.01) and three months (30 versus 44; p-value is less than 0.001) after administration. There was a significant reduction in the occurrence of fatal myocardial infarction (MI) (1 versus 8; p-value is 0.044) and non-fatal MI at Day 7 (1 versus 8; p-value is 0.044), and refractory ischaemia at the end of one month (14 versus 24; p-value is 0.04) and three months (25 versus 36; p-value is less than 0.01) in patients receiving tirofiban as compared to those receiving a placebo. CONCLUSION: It may be concluded that tirofiban has a definite role in improving the outcome of patients with high-risk NSTE ACS.

Recent trends of the emission characteristics from the road construction industry.

Bitumen is a black, thermoplastic, hydrocarbon material derived from the processing of crude oil. At ambient temperature, bitumen is solid and does not present any health/environmental risks. This is one of the main reasons that bitumen is widely used for road construction all over the world. But during manufacturing/modification according to its application, storage, transportation, and use of bitumen is heated giving off various hydrocarbons emissions. In recent years, there has been increasing interest in investigating the potential of bitumen emissions to cause health effects. This is mainly because of the reason that bitumen has small amount of poly-aromatic hydrocarbons, along with some other volatiles like benzene, toluene, etc., which are known to be carcinogenic in nature. Thus, assessment of the emission characteristics and health hazards of bitumen fumes may have far reaching industrial economic and public health implications. In this review, we will discuss about the emission characteristics from bitumen, asphalts, or road construction, which is mainly contributed by bitumen fumes. Sampling strategies and analytical methods employed are also described briefly.

Recent developments of certified reference materials for road transportation.

Chemical measurements often constitute the basis for informed decision-making at different levels in society; sound decision-making is possible only if the quality of the data used is uncompromised. To guarantee the reliability and comparability of analytical data an intricate system of quality-assurance measures has to be put into effect in a laboratory. Reference materials and, in particular, certified reference materials (CRMs) are essential for achieving traceability and comparability of measurement results between laboratories and over time. As in any other domain of analytical chemistry, techniques used to monitor the levels and fate of contaminants in the environment must be calibrated using appropriate calibration materials, and the methods must be properly validated using fit-for purpose matrix-matched CRMs, to ensure confidence in the data produced. A sufficiently large number of matrix CRMs are available for analysis of most elements, and the group of chemicals known as persistent organic pollutants, in environmental compartments and biota. The wide variety of analyte/level/matrix/matrix property combinations available from several suppliers enables analysts to select CRMs which sufficiently match the properties of the samples they analyse routinely. Certified reference materials are playing an increasing role in the monitoring of environmental pollution. This paper is an attempt for describing the recent development of certified reference materials for road transportation, which mainly covers the combustion of fossil fuel, road side dust etc.

Smooth muscle signalling pathways in health and disease.

Smooth muscle contractile activity is a major regulator of function of the vascular system, respiratory system, gastrointestinal system and the genitourinary systems. Malfunction of contractility in these systems leads to a host of clinical disorders, and yet, we still have major gaps in our understanding of the molecular mechanisms by which contractility of the differentiated smooth muscle cell is regulated. This review will summarize recent advances in the molecular understanding of the regulation of smooth muscle myosin activity via phosphorylation/dephosphorylation of myosin, the regulation of the accessibility of actin to myosin via the actin-binding proteins calponin and caldesmon, and the remodelling of the actin cytoskeleton. Understanding of the molecular 'players' should identify target molecules that could point the way to novel drug discovery programs for the treatment of smooth muscle disorders such as cardiovascular disease, asthma, functional bowel disease and pre-term labour.

CaMKIIT287 and T305 regulate history-dependent increases in alpha agonist-induced vascular tone.

CaMKII is a calcium and calmodulin-activated kinase that has been shown to regulate learning and memory in the brain, and contractility in blood vessels. Following Ca activation, CaMKII autophosphorylates, gaining a calcium-independent autonomous activity that reflects a molecular memory of having previously come into contact with calcium. The present study addresses whether the molecular memory properties of CaMKII are involved in the modulation of sustained vascular tone. We demonstrate a history-dependence of alpha agonist-induced vascular tone and show that CaMKII activation in vascular cells is also history dependent. Autophosphorylation of Thr287, which is classically associated with autonomous activity, does not persist during tone maintenance after transient increases in intracellular calcium levels. However, we have found that another site, Thr305, known from in vitro studies to be inhibitory, is regulated by alpha agonists in that the inhibitory action is removed, thus leading to a delayed reactivation of CaMKII as measured by Thr287 phosphorylation. By the use of a small molecule CaMKII inhibitor (KN93) as well as a decoy peptide (autoinhibitory peptide; AIP) we show a cause and effect relationship between CaMKII reactivation and sustained vascular tone maintenance. Thus, it appears that a complex interplay between the regulation of Thr305 and Thr287 provides a novel mechanism by which a history-dependence is developed and contributes to a new facet of molecular memory for CaMKII of relevance to vascular tone maintenance.

Trends of greenhouse gas emissions from the road transport sector in India.

The road transport sector is the largest consumer of commercial fuel energy within the transportation system in India and accounts for nearly 35% of the total liquid commercial fuel consumption by all sectors. Gasoline and diesel consumption for road transportation have quadrupled between 1980 and 2000 due to about nine times increase in the number of vehicles and four-fold increase in freight and passenger travel demands. The paper elaborates the trends of energy consumption and consequent emissions of greenhouse gases such as CO(2), CH(4) and N(2)O and ozone precursor gases like CO, NO(x) and NMVOC in the road transport sector in India for the period from 1980 to 2000. For the first time, efforts have been made to apportion the fuels, both diesel and gasoline, across different categories of vehicles operating on the Indian roads. In order to generate more comprehensive and complete emission estimates, additionally, other minor fuel types like light diesel oil and fuel oil along with lubricants have also been taken into account. Emission estimates have revealed that nearly 27 Mt of CO(2) were emitted in 1980, increasing to about 105 Mt in 2000. Similar trends have also been observed for other gases. Further scope for improvements in emission estimation is possible by generating country specific emission factors for different vehicle categories and improvement in documentation of fuel consumption at segregated levels by fuel types and vehicle types.

Alignment of Ge nanoislands on Si(111) by Ga-induced substrate self-patterning.

A novel mechanism is described which enables the selective formation of three-dimensional Ge islands. Submonolayer adsorption of Ga on Si(111) at high temperature leads to a self-organized two-dimensional pattern formation by separation of the 7 x 7 substrate and Ga/Si(111)-(square root[3] x square root[3])-R30 degrees domains. The latter evolve at step edges and domain boundaries of the initial substrate reconstruction. Subsequent Ge deposition results in the growth of 3D islands which are aligned at the boundaries between bare and Ga-covered domains. This result is explained in terms of preferential nucleation conditions due to a modulation of the surface chemical potential.

Dorsal plating of unstable distal radius fractures using a bio-absorbable plating system and bone substitute.

This study reports the results of open reduction and internal fixation of 26 unstable, intraarticular, dorsally displaced fractures of the distal radius using a bio-absorbable dorsal distal radius (Reunite) plate and calcium phosphate (Biobon) bone substitute. The bio-absorbable plate has the advantage of being low profile, easily contourable and angularly stable. In the majority of cases, this plate produces functional results comparable with metal plates. The Gartland and Werley score was excellent or good in 21 patients. The theoretical advantage over metal plates is in eliminating the need to remove the plate and hence the need for a second operation if implant-related extensor tenosynovitis occurs. Inflammatory tissue reaction to the degradation products of the plate is a potential concern, although the co-polymer ratio used in this plate appears to have reduced the severity of this reaction, which was seen in two patients in this series. The reduction was lost in five patients with severe dorsal comminution. Following this experience, we do not recommend this plating system for fractures with a metaphyseal gap of greater than 7 mm following reduction.

Optical waveguides with an aqueous core and a low-index nanoporous cladding.

We report measurements on planar optical waveguides having an aqueous core and a low-index nanoporous dielectric cladding. Spin-on deposition of the nanoporous dielectric results in a thin (~0.8 microm) low-index cladding layer on a higher-index fused silica substrate, which produces leaky waveguide modes; however, for the aqueous layer thickness needed in most microfluidic applications, a large number of low-loss modes exist. We demonstrate that such a waveguide can be used for efficient collection and transport of fluorescence generated within the aqueous core and show that the use of these nanoporous materials offers advantages over the principal alternative, Teflon(R) AF.

A comparative study between longitudinal and "T" incisions for dorsal plating of the distal radius.

A retrospective review of 24 patients with dorsal incisions for open reduction and internal fixation of Frykman VII/VIII distal radius fractures using a dorsal plate was performed. Half of them had a longitudinal incision while the other half had a T-shaped incision. No difference in the healing properties or wound morbidity could be demonstrated between the two groups. However, the T incision provided improved exposure of the distal radius and patient satisfaction with its cosmetic result was superior. The horizontal limb was well camouflaged within the transverse skin crease on the dorsal aspect of the wrist. The vertical limb did not extend into the dorsum of the hand and could, therefore, be hidden by appropriate clothing.

Calponin is required for agonist-induced signal transduction--evidence from an antisense approach in ferret smooth muscle.

1. The present study was undertaken to determine whether calponin (CaP) participates in the regulation of vascular smooth muscle contraction and, if so, to investigate the mechanism. 2. By PCR homology cloning, the cDNA sequence of ferret basic (h1) CaP was determined and phosphorothioate antisense and random oligonucleotides were synthesized and introduced into strips of ferret aorta by a chemical loading procedure. 3. Treatment of ferret aorta with CaP antisense oligonucleotides resulted in a decrease in protein levels of CaP to 54% of that in random sequence-loaded muscles, but no change in the protein levels of caldesmon (CaD), actin, desmin or extracellular regulated protein kinase (ERK). 4. Contraction in response to phenylephrine or a phorbol ester was significantly decreased in antisense-treated muscles compared to random sequence-loaded controls. Neither basal intrinsic tone nor the contraction in response to 51 mM KCl was significantly affected by antisense treatment. 5. During phenylephrine contractions, phospho-ERK levels increased, as did myosin light chain (LC20) phosphorylation. Phenylephrine-induced ERK phosphorylation and CaD phosphorylation at an ERK site were significantly decreased by CaP antisense. Increases in myosin light chain phosphorylation were unaffected. 6. The data indicate that CaP plays a significant role in the regulation of contraction and suggest that in a tonically active smooth muscle CaP may function as a signalling protein to facilitate ERK-dependent signalling, but not as a direct regulator of actomyosin interactions at the myofilament level.