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Gargi Ganguly,1 Sasanka Chakrabarti,2 Uttara Chatterjee,1 Luciano Saso3 1Department of Pathology, Institute of Post Graduate Medical Education and Research, Kolkata, 2Department of Biochemistry, ICARE Institute of Medical Sciences and Research, Haldia, West Bengal, India; 3Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Rome, Italy Abstract: Alzheimer’s disease and Parkinson’s disease are two common neurodegenerative diseases of the elderly people that have devastating effects in terms of morbidity and mortality. The predominant form of the disease in either case is sporadic with uncertain etiology. The clinical features of Parkinson’s disease are primarily motor deficits, while the patients of Alzheimer’s disease present with dementia and cognitive impairment. Though neuronal death is a common element in both the disorders, the postmortem histopathology of the brain is very characteristic in each case and different from each other. In terms of molecular pathogenesis, however, both the diseases have a significant commonality, and proteinopathy (abnormal accumulation of misfolded proteins), mitochondrial dysfunction and oxidative stress are the cardinal features in either case. These three damage mechanisms work in concert, reinforcing each other to drive the pathology in the aging brain for both the diseases; very interestingly, the nature of interactions among these three damage mechanisms is very similar in both the diseases, and this review attempts to highlight these aspects. In the case of Alzheimer’s disease, the peptide amyloid beta (Aβ) is responsible for the proteinopathy, while α-synuclein plays a similar role in Parkinson’s disease. The expression levels of these two proteins and their aggregation processes are modulated by reactive oxygen radicals and transition metal ions in a similar manner. In turn, these proteins – as oligomers or in aggregated forms – cause mitochondrial impairment by apparently following similar mechanisms. Understanding the common nature of these interactions may, therefore, help us to identify putative neuroprotective strategies that would be beneficial in both the clinical conditions. Keywords: proteinopathy, amyloid beta, oxidative stress, α-synuclein, mitochondrial dysfunction

Stresses arising in plated through holes (PTHs) and surrounding printed wiring board (PWB) substrates due to pin forces of insertion-mount compliant-pin connectors are modeled analytically. The analytical model is based on separation of variable techniques using Fourier series representation of the pin loads, and will be calibrated in the future using both experimental measurements as well as numerical finite element results. Linear and nonlinear results are presented in this paper, to predict deformation and stresses in the assembly. Incremental load-stepping methods are used, to handle nonlinear material properties such as elastic-plastic behavior of copper and post-damage behavior of the PWB substrate. The nonlinearity of the materials is modeled with a simplified bilinear stress-strain curve. The goal is to develop mechanistic predictive models for PTH behavior under insertion forces of compliant pins, to reduce the need for highly repetitive and costly failure analysis for damage evaluation, resulting in significant cost savings to the industry as a whole.

Presents a study which examined the light-induced changes in photoconductivity in deuterated amorphous silicon (α–Si:D). Details on studies of the light-induced changes in hydrogenated amorphous silicon (α–Si:H); Preparation of the dark conductivity, photoconductivity and spin density of the α–Si:D, H films; Conclusion of the study.

A simple notch filter using a single RC ladder section with a floating NIC is presented. The bandwidth of rejection can easily be controlled by varying a resistive component of the ladder section.
Notch filters have drawn much interest due to their use in control and communication systems. Their field of application has increased due to the insertion of active elements, which increase the quality factor Q of the filter by much more than 50%. Realization of filters of this class using operational amplifiers as active devices has been achieved by several authors (Harris 1968, Inigo 1969). A rejection or notch filter using an NIC as the active device has also been studied by Reddy and Rao (1969). Here a circuit has been presented which allows realization of a sharply rejecting notch filter in conjunction with a floating NIC placed in the series arm of the passive ladder section. [ABSTRACT FROM AUTHOR]

Amorphous silicon based solar cells deposited on zinc oxide (ZnO) exhibit reduced fill factor and open circuit voltage in comparison with tin oxide (SnO2). One approach has been to use higher conductivity nanocrystalline layers to overcome the “higher contact resistance.” Recent measurements have found the ZnO–p-layer contact resistance to be unchanged relative to SnO2, while instead, the diode ideality factor is poorer on ZnO. We show that the insertion of a thin, amorphous germanium layer at the ZnO–p-layer interface improves the cell performance and diode ideality factor by suppression of oxygen and zinc incorporation in the silicon layers. [ABSTRACT FROM AUTHOR]

The recombination junction between two cells in amorphous-silicon-based tandem devices can be improved by inserting doped nanocrystalline silicon layers, which have higher conductivities, between doped amorphous silicon layers. However, long deposition times (∼15 min) are required to nucleate and grow these thin nanocrystalline silicon layers on an amorphous-silicon layer. We show that by increasing the phosphorus doping in the amorphous silicon n layer, and replacing the nanocrystalline silicon layers with amorphous germanium layers, a similar performance is obtained with a shorter (∼1 min) deposition time. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The performance of thin-film solar cells based on amorphous silicon germanium alloys (a-SiGe:H) are shown to be relatively sensitive to the contamination level of oxygen and/or nitrogen impurity atoms. Both a-SiGe single-junction solar cells and amorphous silicon (a-Si:H)/a-SiGe:H tandem solar cells were fabricated using a calibrated leak during deposition of individual layers. After light soaking, the tandem cells with a-SiGe layers deposited with an air leak, and observed to incorporate ∼4(2.3)×10[sup19]cm&su[p-3;)oxygen (nitrogen) atoms, have significantly (10%) lower performance. The efficiency of a-SiGe:H single junction cells fabricated with varying air leak rates are found to improve systematically by ∼20% as the incorporated oxygen (nitrogen) concentration decreased by a factor of ∼3 (23) down to 1.3 (0.1)×10{sup19]cm&sup-3;. [ABSTRACT FROM AUTHOR]

We have developed hydrogenated microcrystalline silicon germanium, which exhibits a red-shifted absorption spectrum relative to hydrogenated microcrystalline silicon, as a candidate material for the bottom cell of amorphous silicon-based tandem solar cells. Optical absorption, x-ray diffraction, and Raman scattering spectra are presented in addition to optoelectronic properties and light-induced changes. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The high-spin states in 153Ho have been studied by the 13957La(20Ne,6n) reaction at a projectile energy of 139 MeV at the Variable Energy Cyclotron Centre (VECC), Kolkata, India, utilizing an earlier campaign of the Indian National Gamma Array (INGA) setup. Data from γ-γ coincidence, directional correlation, and polarization measurements have been analyzed to assign and confirm the spins and parities of the levels. We have suggested a few additions and revisions of the reported level scheme of 153Ho. The RF-γ time difference spectra have been useful to confirm the half-life of an isomer in this nucleus. From the comparison of experimental and theoretical results, it is found that there are definite indications of shape coexistence in this nucleus. The experimental and calculated lifetimes of several isomers have been compared to follow the coexistence and evolution of shape with increasing spin. [ABSTRACT FROM AUTHOR]

Background: Osteoarthritis (OA) is characterized by cartilage and synovial inflammation as well as anomalous lower extremity leading to joint pain, and impairment in lifestyle and epidemic of obesity. This study aimed to use the Jumpstart Nutrition® supplement (JNS) for achieving symmetry of aberrant lower extremity and improving the outcome measures in the management of OA., Methods: This week-twelve registry included 108 patients treated with JNS mainly comprised of calcium, phosphorus, magnesium, vitamin-K 2 , coenzyme-Q 10 , vitamin-C, boswellic acids, and curcumin mixed with soy and whey proteins (experimental group) and 72 were treated with symptomatic slow-acting drugs (control group) for chronic OA confirmed with radiological images. The outcome measures (Visual analogue scale, Western Ontario and McMaster Universities Osteoarthritis Index, Knee-injury Osteoarthritis Outcomes Scale, and Body mass index), and anomalous lower extremity included bilateral: knee gaps between biceps femoris-short head and surface of the bed, diameters of muscles at the calf, the thigh, 4cm above and below the patella, angles of straight leg raising, knee- flexion and-extension in supine were evaluated with appropriate protocol at week-0 and at week-12 for both the groups., Results: After week-12, risk ratios of studied lower extremity, and mean ±standard deviation of all outcome measures were significantly improved (p<0.0001), and Kellgren-Lawrence scale (KLS) was upgraded to ≥2 in experimental group compared to control., Conclusions: This registry study indicates that JNS can be used to achieve symmetry of studied lower extremity and to improve the outcome measures safely as an effective management of OA patients confirmed with radiological images correlated with KLS., Competing Interests: The author declares that there are no conflicts of interest regarding the present study., (© The Author(s).)