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Bi2Te3-based thermoelectric materials are proven to be the potential candidate for low temperature commercial applications due to their high thermoelectric conversion efficiency. However, these materials can also be used for elevated temperature application via employing proper dopants with an optimum level of doping. Herein, Sn+2 at Bi+3 site in p-type Bi0.5−xSnxSb1.5Te3 (x = 0, 0.002, 0.005 and 0.010) are doped to optimize high ZT at elevated temperature for the application in power generation. The XRD, SEM and TEM investigations clearly reveal the formation of a single phase of polycrystalline Bi0.5Sb1.5Te3 in all the samples having stoichiometric composition Bi0.5−xSnxSb1.5Te3 (x = 0, 0.002, 0.005 and 0.010). Interestingly, the thermoelectric measurement and Hall measurement result in the suppression of the bipolar effect which ultimately drives to reach the system with maximum ZT ~ 1.27 at 373 K. The enhanced power factor (3.14 × 10–3 W/m K2 at 373 K) combined with the reduction in lattice thermal conductivity (κL ~ 0.61 W/m K at 373 K) results in a peak ZT value ~ 1.27 at 373 K for a stoichiometric composition Bi0.495Sn0.005Sb1.5Te3. This enhancement in ZT is about 38% larger than ZT of commercial composition Bi0.5Sb1.5Te3 (ZT ~ 0.92 at 373 K). The calculated theoretical TE conversion device efficiency η of Bi0.495Sn0.005Sb1.5Te3 was obtained to be η ~ 6.52% for ΔT ~ 123 K and found to be larger than that of the efficiency of matrix. [ABSTRACT FROM AUTHOR]

Thermoelectricity has been proven as a potential technology for the conversion of waste heat into usable electricity. It involves primarily three parameters, namely the Seebeck coefficient, electrical conductivity, and thermal conductivity. However, there are many other interrelated parameters, such as carrier concentration, mobility, effective mass, multi-valley bands, relaxation time, reduced Fermi energy, phonon modes, scattering parameters, and the number of neighbouring atoms in a given structure. The understanding of these parameters is equally important in order to optimize a high figure of merit (ZT). This article addresses the basics of electronic and thermal transport with the help of Boltzmann transport equation, fundamental concepts for the design of thermoelectric (TE) materials, and implementation of several strategies such as alloying, the phonon-glass electron-crystal (PGEC) approach, band engineering and nanostructuring to optimize the ZT of materials, and finally ends with a discussion of the future prospects of heat extraction through different heat sources. [ABSTRACT FROM AUTHOR]

The scientific research and new innovations are associated with the accurate and precise measurements which are crucial for operation of recent civilization. In order to maintain the precision and accuracy in analytical measurements, Reference Materials and Certified Reference Materials (CRMs) play a vital role for improving the measurement capability to obtain the property value close to its true value which in turn revamps the overall growth of country for better quality of life. Certified Reference Materials are basically used to assess the performance of analytical procedures and laboratory apparatus for authentic measurement data. In recent scientific world, many sophisticated instruments are emerging with their various facets of measurement capabilities to cater the need of high end research in the field of academia and industries. In recent years, powder X-ray diffraction (PXRD) has been shown as the most powerful characterization and non-destructive technique to explore the structural investigation in terms of phase identification, size of a unit cell, volume fraction of phases, site occupancy of different elemental component, anti-site defects in materials and having many more other applications. The identification of mentioned information from PXRD instrument is a basic need in material science, geology, polymer, forensic science and environment etc. This article focuses on the importance of CRMs for calibrating the instruments and validation of analytical methods. Also the article explicitly discuss about the importance and applications of PXRD technique together with the role of National Physical Laboratory, India the national institute of measurement NMI of India. [ABSTRACT FROM AUTHOR]

We report the growth of Ni-doped Bi0.5Sb1.35Ni0.15Te3 single crystal via the self-flux method. The crystalline nature of a grown single crystal was confirmed by the X-ray diffraction technique (XRD). Interestingly, the XRD pattern shows a sharp reflections of < 0 0 l > type of planes, revealing the growth of the crystal in c-direction. The grown single crystal was subjected for measurement of field dependence magnetization at 300 K and temperature-dependent magnetic moment. The electronic transport property of bulk single crystal was also carried out in a wide range of temperatures from 150 to 450 K. Reasonably large electrical conductivity σ ~ 1584 S/cm at room temperature was observed which shows ~ 400% enhancement in σ than the electrical conductivity of bare Bi0.5Sb1.5Te3 single crystal (400 S/cm at 300 K). This enhanced electrical conductivity results to significant power factor ~ 1.68 × 10− 3 W/m K2 at 300K which is 163% larger than that of bare Bi0.5Sb1.5Te3 single crystal (6.45 × 10− 4 W/m K2). Magnetic properties of a single crystal of Bi0.5Sb1.35Ni0.15Te3 reveal ferromagnetic behavior at 300 K. The photoluminescence (PL) behavior of Bi0.5Sb1.35Ni0.15Te3 single-crystal was also scrutinized. The PL spectra of Bi0.5Sb1.35Ni0.15Te3 single crystal shows the strong red emission peak in the visible region from 600 to 690 nm upon excitation at 375 nm wavelength, which corresponds to the optical bandgap of 2.1 eV. [ABSTRACT FROM AUTHOR]

An importance of data analysis, methods for homogeneity test and standard uncertainty evaluation associated in any measurement for exact quantification of certified value of any product is vital to be stressed in the scientific community. Herein, we have collectively summarized the detailed discussion on the basics of statistical parameters such as mean, median, mode, standard deviation, variance, range, normal distribution, and central limit theorem. Various statistical analysis methods such as z test, t test, Chi-squared test, and ANOVA including F test have also been discussed in great detail to test the homogeneity of samples for certification of the reference material. The ISO guide 35 (2006) and Guide to Uncertainty in Measurement (GUM) are primarily considered to describe the basic concept of evaluating the associated uncertainty in the light of GUM modelling approach to avoid the error in the measurement which normally occurs in many scientific reports. [ABSTRACT FROM AUTHOR]

We have measured the energy and angle differential ejected electron spectra of C60 as well as Ne atoms in collisions with 4 MeV/u bare fluorine projectile ions. Absolute cross sections have been estimated for electron emission in the energy range of 1 eV–300 eV, including the KLL-Auger electrons for various angles between 30° and 150°. The double differential cross sections for C60 have been compared with the state-of-the-art CDW-EIS model under CNDO approximation as well as with the data for the Ne target. The C60 spectra at all angles show a broad giant plasmon resonance in the low energy region, which is not present in the atomic target data. The angular distribution reveals the dipolar nature of the plasmon excitation. The C K-LL Auger emission from C60 reveals a large angular anisotropy compared to that for a hydrocarbon, e.g. methane target. [ABSTRACT FROM AUTHOR]

Several off-stoichiometric compositions Bi0.5Sb1.5+xTe3+δ (x = 0.2; δ = 0, 0.12, 0.14) were deliberately synthesized to produce in-situ composites based on compositional engineering approach. The structural characterization of these materials employing XRD, SEM, and HR-TEM reveals the formation of in-situ-composites containing Bi0.5Sb1.5Te3 as matrix phase and minor phases of either Sb rich or Te rich in different compositions. Thermoelectric properties of these Bi0.5Sb1.5+xTe3+δ (x = 0.2; δ = 0, 0.12, 0.14) composites were studied in a wide range of temperatures extending from room temperature to 500 K. The electronic transport of these composites exhibits p-type semiconducting materials. The lowest thermal conductivity of ~ 0.69 W/m K @310 K was observed for Bi0.5Sb1.7Te3.12 composite, which was noted to be 14% reduced thermal conductivity when compared with that of the state-of-the-art Bi0.5Sb1.5Te3 (κ = 0.82 W/m K) material. In addition to this, an enhanced power factor was also observed in Bi0.5Sb1.7Te3.12 which is primarily due to increased electrical conductivity of these materials. This enhanced power factor of the composition of Bi0.5Sb1.7Te3.12 coupled with reduced thermal conductivity yields to high ZT ~ 1.13 at nearly room temperature, making these materials viable for large scale applications. [ABSTRACT FROM AUTHOR]

Laser cutting of carbon steel is extensively used across a range of industries, due to its advantage of high speed, low kerf and high quality. Currently, a 1-kW carbon dioxide (CO) laser with its subsonic nozzle assembly can be used only to cut steel plates up to around 10 mm. This paper aims to design and evaluate a high-pressure supersonic laser cutting nozzle assembly, which can enable a 1-kW CO laser to cut steel of up to 50 mm thickness. Basic gas dynamic and compressible flow equations were used to design the supersonic nozzle assembly. The flow of the high-pressure gas jet inside the nozzle assembly was investigated using computational fluid dynamics (CFD), and the structural integrity of the high-pressure nozzle assembly was ensured using finite element analysis (FEA). The gas flow pattern at the exit of the nozzle assembly was computed and compared with the experimental observation made through a shadowgraph technique. Laser cutting experiments were performed with the developed supersonic nozzle assembly to demonstrate cutting of 50-mm-thick low carbon steel with 1-kW CO laser. [ABSTRACT FROM AUTHOR]

A density functional theory + Hubbard U (DFT + U) method is employed to investigate the effect of strain on the electronic and transport properties of the correlated metal LaNiO. LaNiO without strain is characterized by a low temperature Fermi liquid behaviour of resistivity, a negative Seebeck coefficient and a positive Hall coefficient. Density of states, resistivity, thermopower and Hall coefficient obtained within the DFT + U approach reveal that LaNiO under both compressive and tensile strain is more metallic compared to the unstrained system. However, LaNiO under tensile strain is found to be more strongly correlated than that under compressive strain. Electron localization function calculation shows that there is a substantial increase in the covalent part of the chemical bonding, which corroborates an increase in the resistivity for LaNiO under tensile strain. Our first-principle-based calculation clearly demonstrates that the transport properties of LaNiO can be tuned by applying suitable strain. [ABSTRACT FROM AUTHOR]

This study aims at reconstructing paleovegetation history in the northeast Himalaya during the past 2700 yrs using a 100 cm long sedimentary section selected near Anini village, Dibang valley, Arunachal Pradesh (India). Stable carbon and nitrogen isotopic composition (δC and δN); and total organic carbon (TOC) and total nitrogen (TN) content in organic matter as well as magnetic susceptibility were determined. Results obtained show a strong correlation between TOC-TN indicating similar source for organic matter. δC and TOC/TN ratio throughout the stratigraphic unit seems to be poorly correlated which suggests that the primary carbon isotope signatures are preserved in the sedimentary environment. Overall, δC values of the organic matter in the section vary in the range from-23.9 to-21.2 ‰ which is typical of mixed C-C plants.. A distinguishable increasing trend in δC during 2700 to 1300 yrs indicates change in vegetation pattern from C to C plants due to significant climate change from wetter to drier conditions. After 1300 yrs δC values decrease rapidly by 1.3‰ and suggest increasing abundance of C plants in wetter climatic condition. The relatively small variation in δC values in the upper part of the section during 1200 yrs to present suggest a stable climatic condition. [ABSTRACT FROM AUTHOR]

The article presents abstracts of various studies on Quality of Life (QoL) after hernia surgery which includes laproscopic inguinal hernia repair with a self-fixating mesh, effect of tach choice and number of QOL in a laproscopic inguinal hernia repair and variation in care processes in patients undergoing hernia repair. [ABSTRACT FROM AUTHOR]

Adsorption of tetracycline from separate solutions of ethanol, p-dioxane, and chloroform onto synthetic hydroxyapatite (containing about 1.5 monolayer of physisorbed water) was studied in order to understand its interaction with bone and teeth. The adsorption isotherms of tetracycline are reversible and Langmuirian from ethanol and p-dioxane and are almost identical. The isotherm is irreversible from chloroform, and a constant amount of adsorbate is removed from the solutions above a certain concentration. The irreversibly adsorbed compound is completely desorbed by prolonged repeated washing with ethanol. An analysis of the reversible isotherms showed that at maximum coverage the ring or polycyclic structure of the molecule stands perpendicular to the surface with appropriate hydroxyl groups and keto-oxygens hydrogen bonded to the surface. However, the adsorption from chloroform is irreversible and at maximum adsorption is about one and half times larger than that from either ethanol or p-dioxane. The process of adsorption does not affect the chemical integrity of tetracycline. [ABSTRACT FROM AUTHOR]

Adsorption of water was studied gravimetrically at 23 degrees C in an open system at several relative humidities on a variety of apatitic calcium phosphates including enamel, deproteinized enamel, and bone mineral. The amount of adsorbed water increases linearly with the surface areas of the synthetic apatites and does not appear very sensitive to calcium to phosphorus ratio of the apatites. The adsorption results correlate very well up to about two monolayers with a conventionally determined isotherm. Higher uptake of water even by "deproteinized" enamel or bone may be due to the presence of pore structure and incompletely removed organic matter. [ABSTRACT FROM AUTHOR]

Summary: Association between warfarin use and fracture risk is unclear. We examined the association between long-term warfarin use and fracture risk at the hip, spine, and wrist in elders. No significant association was found between long-term warfarin use and fracture risk, despite biological plausibility. Introduction: Prior studies examining the association of warfarin use and osteoporotic fractures have been conflicting, potentially related to methodological limitations. Thus, we examined the association of long-term warfarin use with risk of hip, spine, and wrist fractures among older adults with atrial fibrillation, attempting to address prior methodologic challenges. Methods: We included men and women ≥65 years of age with incident atrial fibrillation and without prior history of fractures from The Health Improvement Network followed between 2000 and 2010. Long-term warfarin use was defined in two ways: (1) warfarin use ≥1 year; (2) warfarin use ≥3 years. Propensity-score matched cohorts of warfarin users and nonusers were created to evaluate the association between long-term warfarin use and risk of hip, spine, and wrist fractures separately as well as combined, using Cox-proportional hazards regression models. Results: Among >20,000 participants with incident atrial fibrillation, the hazard ratios (HR) for hip fracture with warfarin use ≥1 and ≥3 years, respectively, were 1.08 (95%CI 0.87, 1.35) and 1.13 (95 % CI 0.84, 1.50). Similarly, no significant associations were observed between long-term warfarin use and risk of spine or wrist fracture. When risk of any fracture was assessed with warfarin use, no association was found [HR for warfarin use ≥1 year 0.92 (95%CI 0.77, 1.10); HR for warfarin use ≥3 years 1.12 (95%CI 0.88, 1.43)]. Conclusions: Long-term warfarin use among elders with atrial fibrillation was not associated with increased risk of osteoporotic fractures and therefore does not appear to necessitate additional surveillance or prophylaxis. [ABSTRACT FROM AUTHOR]

Aim: To review our practice of Meckel's Tc-99m pertechnetate scans over 18 years with regard to indications for the test, sensitivity and specificity in our particular referral patients' population. Materials and methods: This is a retrospective review of Meckel's scans performed in two paediatric tertiary care teaching hospitals from April 1993 to March 2011 and followed up till October 2011. The scan was performed according to published international guidelines. 183 patients were included in this study. We classified the patients into two groups: group 1, which included 77 patients (42 %) presenting with painless per rectum bleeding, and group 2, which included 106 patients (58 %) presenting with other non-specific symptoms (e.g. abdominal pain, possibly associated with nausea and/or vomiting, failure to thrive). Data were analysed using Chi square test, considering P value less than 0.05 as significant. The age of the patients ranged from 4 days to 16.5 years (median 3 years). Results: 161 of the total 183 children on the study (88 %) had a negative Meckel's scan, and 22 children (12 %) had a positive scan. In the group with a positive Meckel's scan (22 children), all patients underwent surgical exploration and ectopic gastric mucosa was found in 17 cases (77 %, true positives). In the remaining 5 cases (23 %), there was no evidence of ectopic gastric mucosa (false positives). Within the group with a negative scan, 8 children (5 %) underwent surgery; only 1 child had a ectopic gastric mucosa detected following surgery (false negative). In other 52 children (32 %) of the group with a negative Meckel's scan, an endoscopy was done, which showed a normal result in 21 children and was abnormal in 31 children. Of the remaining 101 (63 %) children with a negative Meckel's scan, 74 children (46 %) improved without any further intervention. In 13 cases (8 %), other pathologies were identified. The sensitivity and specificity of the Meckel's scan for ectopic gastric mucosa were 94 and 97 %, respectively. The Meckel's scan was positive in 26 % of the patients of group 1 and in only 2 % patients of group 2. The difference between the two groups was highly significant [ P < 0.0001 (Yates-corrected Chi square); odds ratio 18 (Woolf-logit method 95 % CI)]. Conclusion: The Meckel's scan retains a high diagnostic accuracy in children for detecting a Meckel's diverticulum with ectopic gastric mucosa within it, when performed according to the recommended guidelines. The test yields its highest positive result in children presenting with significant per rectum bleeding. [ABSTRACT FROM AUTHOR]

Four levels of terraces located along Siang River, north of Main Central Thrust at Tuting, NE Himalaya are dated using Optically Stimulated Luminescence (OSL). The dating technique is applied using (1) Blue LED stimulation on Quartz (2) Infrared Stimulated Luminescence (IRSL) stimulation on Feldspar at 50 °C and (3) Infrared Stimulated Luminescence stimulation on Feldspar at an elevated temperature of 225 °C. The results indicated that the later two protocols on feldspars yielded overestimated ages that suggested incomplete bleaching of luminescence signals in feldspar. The ages derived using quartz suggested a nearly continued valley aggradation from >21-8 ka with three phases of bedrock incision. The phase of aggradation coincides with a climatic transition from cold and dry Last Glacial phase to warm and wet Holocene Optimum. The bedrock incision phases centered at <21 ka, ∼11 ka and ∼8 ka indicate towards major episodes of tectonic uplift in the region around Tuting. [ABSTRACT FROM AUTHOR]

Summary: Association between dietary protein and fracture risk is unclear. We examined association between energy-adjusted protein intake and hip fracture risk in elders. The risk of hip fracture was reduced in upper quartiles of protein intake when compared with lowest quartile. Introduction: Studies of the association between dietary protein intake and hip fracture risk are conflicting. Therefore, we examined protein intake and hip fracture risk in a population-based group of elderly men and women. Methods: Five hundred seventy-six women and 370 men from the Framingham Osteoporosis Study with no previous history of hip fracture completed Food Frequency Questionnaires. Energy-adjusted protein intake was evaluated as a continuous variable and as quartiles. Incidence rates and hazard ratios were calculated, adjusting for age, BMI, sex, and energy intake. Results: Among 946 participants (mean age 75 years), mean protein intake was found to be 68 gm/d. Increased protein intake was associated with a decreased risk of hip fracture compared to those in the lowest quartile of protein intake (Q2 HR = 0.70, Q3 HR = 0.56, and Q4 HR = 0.63; all p values ≥ 0.044), p for trend was 0.07. When a threshold effect was considered (Q2-4 vs Q1), intakes in the higher quartiles combined were associated with a significantly lower risk for hip fracture (HR = 0.63; p = 0.04). Conclusion: Our results are consistent with reduced risk of hip fracture with higher dietary protein intake. Larger prospective studies are needed to confirm and extend this finding in elderly men and women. [ABSTRACT FROM AUTHOR]

This paper investigates the electrical characteristics at low temperatures through C-V, I-V and conductance measurements to understand the interface behavior of HfO and p-type GaAs bulk substrate. Room temperature interface state density, D, estimated for as-deposited Ti-Au/HfO/GaAs capacitors was found to be 3.68 × 10 cm eV. Low temperature measurement suggests that only fast interface states contribute to the conduction process. When the characteristics of two different metal gates were compared, the accumulation capacitance density observed to be 1.4 and 8.98 fF/μm for Be-Au/HfO/GaAs and Ti-Au/HfO/GaAs, respectively at 1 MHz. [ABSTRACT FROM AUTHOR]

BACKGROUND AND AIMS: Given the high risk of subsequent fracture among elderly persons with fracture, it is important to initiate secondary treatment for osteoporosis. Acute rehabilitation centers may offer a unique opportunity to introduce treatment. Therefore, we evaluated willingness-to-participate and compliance with evidence-based interventions for the secondary prevention of osteoporotic fracture in a non-randomized study conducted in the acute rehabilitation setting. We also described differences in baseline characteristics between study participants and non-participants. METHODS: All consecutive, communitydwelling admissions to an acute rehabilitation unit (Boston, MA) with the diagnosis of fracture were screened for enrollment. Eligible subjects were offered a free, 6-month supply of alendronate/cholecalciferol (70 mg/2800 IU weekly), calcium and vitamin D supplements, and fall prevention strategies. Six-month compliance (>/=75% consumption of medication or supplement) with the interventions was determined at a home visit. RESULTS: Among 62 eligible subjects, 25 agreed to participate. Non-participants were older than participants (86 vs 80 yrs, p<0.01). There was no significant difference between other characteristics of participants and non-participants including sex, weight, type of fracture, cognitive status, and functional status. The most common reason for non-participation was reluctance to take another medication. Among participants, only 52% were compliant with alendronate and 58% were compliant with calcium and vitamin D supplementation at 6 months. CONCLUSIONS: Willingness- to-participate and compliance with secondary prevention strategies for osteoporosis was low in the acute rehabilitation setting, even when medications were provided free of cost. Educating individuals with fracture and their families on the consequences and treatment of osteoporosis may help to decrease the risk of sustaining a second fracture by accepting secondary preventive measures. [ABSTRACT FROM AUTHOR]

Samples of mild steel have been cut on a CO2 laser machine using the principle of laser assisted oxygen cutting (LASOX). The combined effects of input process parameters (cutting speed, gas pressure, laser power and stand off distance) on cut quality (heat affected zone (HAZ) width, kerf width and surface roughness) have been studied. Regression analysis has been used to develop models that describe the effect of the independent process parameters on cut quality. Using the developed model, we attempted to optimize the input parameters that would improve the cut quality (minimization of HAZ width, kerf width and surface roughness), increase the productivity and minimize the total operation cost. We found from the study that the gas pressure and cutting speed had pronounced effect on cut quality. Low gas pressure produces lower HAZ width, lower kerf width and good surface finish whereas increase in speed results in higher HAZ width, lower kerf width and good surface finish. [ABSTRACT FROM AUTHOR]

Geological mapping between Lohit and Dibang valleys of eastern Arunachal Pradesh reveals the existence of five thrust bound tectonostratigraphic units. In ascending structural order from SW to NE these are: (1) Sewak Group, (2) Lalpani Group, (3) Mayodiya Group, (4) Tidding Formation and (5) Lohit plutonic complex. This differs from previous mapping, because the three tectonostratigraphic units (Sewak, Lalpani and Mayodiya) were grouped under a single unit, referred as the Mishmi crystallines. The low-grade metamorphics of the Sewak Group occur at two different tectonic levels, one as persistent belt in the foothills and the other in the tectonic window beneath the high-grade metamorphics of the Mayodiya thrust sheet in the Higher Himalaya. The Tidding suture is the southeastern extension of the Indus-Tsangpo suture zone. [ABSTRACT FROM AUTHOR]

A catastrophic failure of a Stacker-cum-Reclaimer led to loss of several days of service in one ore handling plant in India. The failure was severe enough to initiate an investigation into the possible causes of failure and estimation of the residual life for other units of Stacker-cum-Reclaimer of the same design and age, working in the plant. The failure analysis included a visual inspection of the failed structure, metallographic studies, static stress and stability analysis under normal operating conditions, stress analysis for a possible impact load on the structure, experimental stress analysis, and fatigue life cycle analysis. The results obtained indicate that the failure could be caused by an impact load arising out of some operational conditions resulting from the conditions of the rail track on which the machine travels. The material properties, the physical conditions of the material, and a fatigue analysis indicate that the existing system can work for several more decades, provided some checkpoints are planned and instituted to monitor the health of the structure at regular intervals. [ABSTRACT FROM AUTHOR]

In view of the renewed interest in the study of energetic particles in the outer radiation belt of the earth, we feel it will be helpful in looking for the energy dependence of the electron energy spectrum at geostationary orbit. This may give us some insight into how we can safeguard geostationary satellites from functional anomalies of the deep dielectric charging type, which are caused by charge accumulation and subsequent discharge of relativistic electrons. In this study we examine whether there is any energy dependence in relativistic electron enhancements at geosynchronous altitudes during solar energetic proton events of 2005. [ABSTRACT FROM AUTHOR]

In the present study, we investigate the possible relationship of IP parameters of solar wind and interplanetary magnetic field with ground-based geomagnetic indices. To carry out the study, we take all the IP shock events listed by Proton Monitor onboard Solar and Heliospheric Observatory (SOHO) during 2005, and plot the time variations of all the IP parameters and geomagnetic parameters (±5 days), centered at the shock arrival time. Next, we obtain scatter plots of absolute values of solar wind parameters such as Vsw, Nsw and Interplanetary Magnetic Field (IMF) components Bx, By, Bz and total B with the values of geomagnetic parameters such as Dst, Kp indices, dayside Magnetopause (MP) distance and Cosmic-Ray Neutron Monitor count (CRNM). The scatter plots show that before the IP shock, the pattern is random with no clear relationship. Following the shock, a clear pattern emerges with a type of relationship being seen - clear for SHARP shocks and less clear for DIFFUSE shocks. A total of 10 shock events for 2005 have been studied. Typical examples of this behaviour are the shock events of January 21, 2005 and May 15, 2005. Our study suggests a definite correlation between changes in the solar wind and interplanetary magnetic field parameters and ground-based geomagnetic response. We are trying to obtain quantitative relationships between these for shock events of 2005. [ABSTRACT FROM AUTHOR]

We have studied fast ion-atom and electron-atom collision processes using a reconditioned high resolution X-ray spectrometer. The X-rays, generated by the collisions, are dispersed by a curved ADP crystal (Johansson geometry) and detected by a gas proportional counter. A self-written LabVIEW based program has been used to give precise and controlled movement to the crystal and for data acquisition. The performance was tested by detecting the Kα diagram and satellite lines of several elements. The Kα satellite lines of Al have been studied in collision with 3-12 keV electrons and 40 MeV C4+ ions. In ion collisions as large as four L-vacancies are created simultaneously with the K-vacancy, compared to two satellites in case of the e-impact. In addition, we have measured the X-rays from H-, He- and Li-like Si ions which arise due to the electron loss/capture process in highly charged 80 MeV Si7+ ions in collision with thin carbon foil. Approximate charge state distribution has been obtained using this new technique. [ABSTRACT FROM AUTHOR]

The use of diamond for infrared (IR) transmitting applications is of paramount importance to the defense industries. Diamond-coated IR transmitting materials are used on smart weapons and aircraft that use substrate materials such as silicon and germanium. In this investigation, diamond sheets were deposited using chemical vapor deposition. The as-grown diamond sheets were characterized for hydrogen content using detailed IR analysis. The deconvolution of the spectra in a three-phonon region (2700-3150 cm-1) showed a number of vibration modes corresponding to the spmCHn phase of carbon. The spectra representing (100) and (111) textured diamond sheets, grown under different conditions, were compared. The (100) textured sheets contained two dominant peaks centered at 2860 and 2930 cm-1, which correspond to the symmetric and asymmetric stretch bands of the CH2 group. However, the sheet with (111) texture displayed multiple CH, CH2, and CH3 peaks on the spectrum. Using a standard sample called polymethyl methacrylate with known concentration, the hydrogen content associated with various modes was evaluated in the diamond sheets. IR active hydrogen in the chemical vapor deposited diamond sheets was also calculated by evaluating the area of the IR band. A discrepancy of one order of magnitude was found in the calculated and measured value. Using these measurements we suggest that the oscillator strength of the different IR modes varies depending upon the structure and H content of CVD diamond sheets. [ABSTRACT FROM AUTHOR]

Polycrystalline diamond films with a predominant (100) texture were deposited onto silicon substrates using hot-filament chemical vapor deposition. During film deposition, different temperature gradients were created and imposed laterally across the substrate materials. Films grown under a gradient of 100 °C cm-1 displayed large (100) oriented grains. No crystallite (100) orientation was observed in the as-grown films prepared without a temperature gradient. It was observed that the diamond grain size varied as a /unction of the gradient. The lower gradient resulted in smaller grains and vice versa. Furthermore, the size of the grains was a function of the deposition time. The orientation of the diamond grains changed gradually across the substrate from (100) to (110) orientation as we scanned from the high-temperature to the low-temperature zone. The films were characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and Fourier transform infrared (FTIR) spectroscopy. XRD showed strong (400) reflections in the oriented samples. SEM results indicated the presence of smooth diamond surfaces consisting of predominantly (100) oriented platelets. As the (100) oriented diamond grains were grown on top of the (100) oriented silicon substrates, the faces were mostly aligned parallel to the substrate surface resulting in the deposition of a smooth diamond surface. AFM observations revealed the presence of steps located at the boundaries of the oriented grains. FTIR results showed the characteristic difference in hydrogen bonding in the oriented samples and gave useful information about mechanisms responsible for the orientation. Quantitative analysis was carried out to measure the H content in the films, and it was found that the oriented films contained less hydrogen. Our findings suggest that high saturation of carbon and a concentration gradient of sp³ CH2 species can be the key... [ABSTRACT FROM AUTHOR]

The article states that in India, less attention has been paid on the effect of ambient air lead (PbA) levels, on blood lead (PbB) levels of pregnant mothers. It cites a study conducted to monitor PbA levels and correlate effects of PbA levels on PbB levels of pregnant mothers during the course of pregnancy. Results of the study revealed that the rate of release of bone lead is accelerated during pregnancy and the accelerated bone lead release continues into lactation and lactation release can in fact exceed that occurring in pregnancy. The accelerated bone lead releases during lactation extend the developmental lead exposures to early infancy via breast milk lead intake.

OBJECTIVES: We examine the scope and nature of the recommendations that emerged from the Healthy Start Fetal and Infant Mortality Review (FIMR) projects and explore their use to promote systems change. METHODS: The FIMR process of 16 of the 22 federal Healthy Start projects was reviewed. We analyzed data from a June 1996 survey developed and administered by the MCH Bureau which gathered information about recommendations produced by the FIMRs. We supplemented these data with information gathered through follow-up telephone interviews and by abstracting information from grant documents. RESULTS: The 16 Healthy Start FIMRs reviewed approximately 1300 cases between 1991 and 1996. A total of 303 specific action strategies were recommended, reflecting eighteen specific substantive areas of concern. Overall, 65% of recommendations fell under the rubric of 'program' functions, 31% under 'practice,' and 4% under 'policy.' Healthy Start itself was most commonly targeted for action. The second most frequent target for action were public and private provider institutions. Public policymaking entities were rarely targeted. CONCLUSIONS: In the first several years of implementation, with few exceptions these FIMRs sought limited change. They worked almost exclusively within their own span of control to effect important, but limited changes in systems serving women and their infants. As public health professionals seek to monitor population health, the field must strengthen any and all vehicles that draw upon collaborative structures at the community level to not only uncover problems, but to address them as well. [ABSTRACT FROM AUTHOR]

A new antigenic system in the rat homologous to the Qa/TL antigen system in the mouse has been characterized. It was detected by antibodies raised in donor-recipient combinations that were matched for the RT1. A, B, D, E loci in the major histocompatibility complex (MHC): (R11×BN)F anti-BN.1L(LEW), (R18×BN)F anti-BN.1L, and BN.1LV1(F344) anti-BN.1L. Absorption analyses using these antisera and a variety of inbred, congenic and recombinant strains identified three alleles, RT1.G, G, G, of which G is a null allele. The strain distribution of these alleles was determined, using 37 strains of rats representative of all of the prototypic haplotypes and a number of congenic and recombinant strains. The use of the congenic and recombinant strains showed that the RT1.G locus was linked to the MHC and that the most probable gene order was A-E-G. Testcross analysis showed that the map distance between A and G was 1.4 cM(4/285 recombinants). The RT1.G antigen has a heavy chain of M 46 000 and is present on both T and B cells. [ABSTRACT FROM AUTHOR]

The surface areas of three different samples of hydroxyapatite, samples of deproteinized bone, and samples of whole and deproteinized enamel were determined by adsorption of an adduct (the diglycidyl ether of bisphenol A with N-phenylglycine) from methylene chloride solution. In all cases, the surface areas of these samples agree well with those obtained by the BET (N) method. [ABSTRACT FROM AUTHOR]

The "plug and patch" mesh herniorrhaphy has become a popular option for inguinal hernia repair. Previous reports have documented several complications with some regularity. This case presents an additional complication and offers suggestions as to why this complication and others might occur. [ABSTRACT FROM AUTHOR]