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IN BRIEF The SEC recently required registrants to disclose information on human capital resources that is material to understanding a company's business. Although this represents a step forward for sustainability [...]

Background: Black/African Americans experience a high burden of Alzheimer disease and related dementias yet are critically underrepresented in corresponding research. Understanding barriers and facilitators to research participation among younger and older African Americans is necessary to inform age-specific strategies to promote equity in studies of early- and late-onset neurodegenerative diseases. Study Design: Survey respondents (n= 240) rated barriers and facilitators of research participation. Age-specific differences were evaluated using nonparametric Kruskal–Wallis tests across respondents aged 18–44 years (n= 76), 45–64 years (n= 83), and ≥ 65 years (n= 81). Strategies to mitigate barriers and promote facilitators were further explored via community-based focus groups. Pooled frequency of common themes discussed in focus groups were evaluated and compared across different ages including ≥ 45 years, ≥ 65 years, and mixed ages ≥ 45 years. Results: Younger respondents (aged 18–44 and 45–64 years) expressed a greater need for flexibility in when, where, and how research testing takes place versus adults ≥ 65 years. Focus groups emphasized long-lasting consequences of systemic racism and the need to build and foster trust to resolve barriers and promote research engagement amongst African Americans. Discussion: Age-specific strategies are needed to increase engagement, address recruitment disparities, and promote retention of African American participants in memory and aging studies across the lifespan.

•Rapid targeted genotyping of CSF prospectively detected hallmark single-nucleotide variants in 42% of patients with new CNS tumors.•Integrating this approach in a CLIA environment accelerated times to diagnosis and treatment for patients with newly diagnosed CNS lymphoma.

Deep-hole drilling (DHD) on Ti6Al4V has been a long-standing area of research for many researchers and manufacturers and has faced challenges such as frequent resharpening or complete replacement. DHD's benefits make it appropriate for applications such as gun barrels, fuel lines for fuel injectors, lubricant feeds for gears and crankshafts, and aircraft components such as landing gear. Cutting fluids (CFs) are used in machining to provide cooling and lubrication to the machining zone. Conventional CFs can cause respiratory and skin disorders in workers. The conventional coolant is replaced by cryogenic coolants, which are considered eco-friendly and overcome problems in the machining process. To investigate alternative cooling techniques in depth and to change the use of mineral-based CFs, this study investigated the performance of DHD under various cooling conditions, namely flood cooling, liquid carbon dioxide (LCO2), and liquid nitrogen (LN2). The output parameters considered in this study were hole wall temperature, surface roughness, tool wear, chip morphology, circularity, and cylindricity. The Taguchi L27 OA was used in the design of the experiments, and the COPRAS optimization technique was employed to optimize the machining parameters. The cryogenic coolants exhibited improved performance in all the machining parameters. The surface roughness was reduced using LN2; the reductions observed when compared with flood conditions, and LCO2were in the range of 44–70 % and 30–60 %, respectively. The hole wall temperature recorded under flood conditions ranged from 37 to 34 °C, whereas the temperatures recorded in LCO2and LN2ranged from 72–55 °C and 50–45 °C, respectively. The optimal cutting conditions for performing DHD on Ti6Al4V were a spindle speed of 1100 rpm and a 25 mm/min feed rate under LN2cooling condition. Furthermore, the study was extended by applying the Pugh matrix approach to assess the sustainability of selected cooling conditions. A life cycle assessment (LCA) was also conducted for the machining process, revealing insights into machining efficiency. The LN2cooling condition outperformed the other cooling conditions, considering all the parameters contributing to sustainability.

One of the objectives behind a progressive income tax structure is to achieve a redistribution of wealth by imposing higher taxes on those who earn more compared to those who [...]

This study used ultrasonic aided stir casting to cast composite with aluminum alloy, and the prepared composite materials were characterized by mechanical and microstructural analysis. In this study, micron-sized ceramic particle titanium carbide (TiC) in distinct ratios (0, 3, 6, 9, 12, 15, and 18 wt.%) along with 1 wt.% of montmorillonite nanoclay (MN) were reinforced into the matrix of AA1100 alloy. Microstructural analysis shows that the MN and TiC particles are evenly distributed inside the matrix of AA1100, as seen from scanning electron microscopy (SEM) images. Higher porosity is achieved for AA1100 + 1wt.%MN + 18wt.%TiC, which is 43.33% higher than the AA1100 + 1wt.%MN + 15wt.%TiC composite. When compared to the base alloy, the micro-hardness, ultimate tensile strength, flexural and impact strength of the aluminum MMCs increased dramatically with an increase in TiC percentage until 15wt.% of TiC, whereas 18wt.% TiC addition lowers the tensile, flexural, and impact strength by 2.97, 3.54, and 10.33%, respectively, than the addition of 15wt.%TiC. The wear rate of the composite is reduced with the inclusion of solid lubricant MN. With the addition of MN with 3, 6, 9, 12, and 15 wt% TiC, the composite shows a further reduction in wear rate of 41.66, 50, 53.57, 55.95, and 59.52%, respectively, compared to the base alloy. The icorrof AA1100 + 1wt.%MN + 15wt.%TiC composite is four times lower than the base alloy, revealing superior corrosion resistance compared to other composites and base alloy. Orowan strengthening mechanism and abrasion and adhesive type wear mechanism are identified as predominant mechanisms.

Interest in optical wireless communications (OWC) as a possible complement to RF technology has increased recently. However, the propagation of optical beams through the atmosphere distorts the beam's amplitude and phase, resulting in information loss and significant noise. Arising due to a combination of multiple absorption and scattering events, the distortion of the beam makes optical communication difficult. In some cases, the orbital angular momentum of light (OAM), along with various deep learning algorithms (DL), could be helpful to mitigate the problem and provide high-capacity optical communication links. In this work, we propagate Laguerre-Gaussian (LG) beams with different topological charges (l) under diffuse and turbulent conditions and develop a deep-learning classification network to characterize the ‘l’ of the LG beam. The proposed method is later implemented using a laboratory setup demonstrating communication on the optical table. The results show that the proposed algorithm can identify the modes of the LG beam with high accuracy even when the optical beam propagates through highly turbulent and scattering media. To demonstrate the robustness of the proposed OWC system, small grayscale images are transmitted over the communication channel. A bit error rate (BER) of only $2.3 \times {10}^{ - 4}$ and $9.7 \times {10}^{ - 4}$ for the tabletop experiment and the simulations, respectively. The demonstrated low BER in the proposed OWC system suggests promising applications for secure and reliable data transmission in adverse atmospheric conditions, highlighting the potential of this method in advancing optical wireless communication technologies.

Byline: Geeta. Narayanan, M. Ganesh, Rishabh. Kumar Objectives: The primary objective of this study was to compare the treatment response of cervical carcinoma patients infected with human papillomavirus (HPV) 16 [...]

IN BRIEF In the past few decades, large publicly traded companies have faced increasing pressure not only to perform well financially, but to do so while exhibiting environmental and social [...]

Background: Declines in instrumental activities of daily living like driving are hallmarks sequelae of Alzheimer’s disease (AD). Although driving has been shown to be associated with traditional imaging and cerebrospinal fluid (CSF) biomarkers, it is possible that some biomarkers have stronger associations with specific aspects of driving behavior. Furthermore, associations between newer plasma biomarkers and driving behaviors are unknown.Objective: This study assessed the extent to which individual plasma, imaging, and CSF biomarkers are related to specific driving behaviors and cognitive functions among cognitively normal older adults.Methods: We analyzed naturalistic driving behavior from cognitively healthy older drivers (N = 167, 47% female, mean age = 73.3 years). All participants had driving, clinical, and demographic data and completed biomarker testing, including imaging, CSF, and/or plasma, within two years of study commencement.Results: AD biomarkers were associated with different characteristics of driving and cognitive functioning within the same individuals. Elevated levels of plasma Aβ40were associated with more speeding incidents, higher levels of CSF tau were related to shorter duration of trips, and higher CSF neurofilament light chain values were associated with traveling shorter distances, smaller radius of gyration, and fewer trips at night. We demonstrated that plasma, like CSF and imaging biomarkers, were helpful in predicting everyday driving behaviors.Conclusions: These findings suggest that different biomarkers offer complementary information with respect to driving behaviors. These distinct relationships may help in understanding how different biological changes that occur during the preclinical stage of AD can impact various sensorimotor and cognitive processes.

The idea of fiscal federalism has been practised in India for quite some time, but the specifics of how it should work have become less clear over the course of that time. In the future, its guiding ideas and operational methodologies will need to be progressively developed and improved; in the meantime, these things need to be carefully evaluated. The India of today is considerably different from the India that created its constitution in 1950. This may be seen most clearly in the governance 'matrix', economic development, institution-building, and multilateral interactions that exist in modern India. When it comes to its relationships with other governments, India is in the midst of a period of transition right now. It is becoming increasingly difficult to distinguish between boundaries based on linguistic concerns and administrative convenience in today's world due to the transformations brought about by innovation and migration, among other factors. As technology progresses, it will become one of the most important socio-economic factors that will impact the long-term viability of India's fiscal federalism system. Increased mobility, market integration, and market integration are two other trends to watch for them.

The plant-based green synthesis method is creating more interest in safety, low-cost, biocompatibility, and eco-friendly approaches to producing nanoparticles biologically than chemical and physical methods of synthesis. The copper oxide nanoparticles (CuONPs) attract researchers due to the wide range of industrial, pharmacological, and biomedical applications that depend on the size, charge, and shape of the nanoparticles. This research work aimed to synthesize CuO nanoparticles using aqueous extract of Salvinia cucullata, characterization, and assessment of in vitroantibacterial, antioxidant, and anticancer activity. The characterization of CuONPs was performed by different techniques which include UV spectroscopy, FTIR, XRD, TEM, SEM, EDXS, and Zeta size and potential analysis. UV spectroscopy confirms the synthesis of CuONPs with an absorbance peak of 266 nm. The monoclinic crystalline nature of CuONPs was revealed by XRD analysis, and this pattern exhibited similar diffraction peaks with no significant shift in peak position. The functional groups of phytocomponents present in the aqueous extract of S. cucullatawhich act as reducing and stabilizing agents responsible for CuONPs synthesis were analyzed by the FTIR technique. The spherical shape of the synthesized CuONPs was ascertained by SEM and TEM image techniques, and the selected area for electron diffraction shows the crystal orientation of the CuONPs. EDXS shows that only copper and oxygen were present and the synthesized CuONPs are in pure form. The average size and charge of the synthesized CuONPs were analyzed by PSA as 67.5 nm and − 2.2 mV. The antibacterial potential of synthesized CuONPs was tested against both gram- positive and gram-negative bacterial strains. Among all eight strains, the maximum and minimum zone of inhibition was observed against Enterococcusspp. and Aeromonas hydrophila(maximum inhibition against gram-positive strains than gram-negative strains). The antioxidant and anticancer activity of CuONPs were tested against DPPH and MCF-7 breast cancer cell line and are observed with increased activity in a dose-depending manner with the IC50 value of 81.21 μg/ml and 68.16 μg/ml concentration. The green synthesized CuONPs were characterized and exhibited antibacterial, antioxidant, and anticancer activity. Thus, CuONPs can be utilized for broad-spectrum biomedical applications.

Following the seminal work of Aleskovskii [1] and Suntola [2] in establishing the field of ALD science, the subject has rapidly expanded in both academic and commercial arenas to encompass […], Extreme and non-planar substrate topographies that provide challenges for conventional thin film deposition techniques are abundant. Such applications span the range of structures from DRAM trench cells and MEMS devices to coatings of esoteric materials such as aerogels, viruses, nanotubes, microlenses, piping, grains and particles, and even porous dental material. For these types of important and interesting applications, atomic layer deposition (ALD) provides an exceptional technology for overcoming such challenges in order to achieve superior film uniformity, step coverage, and film conformality.

The 16th Amendment to the U.S. Constitution gave Congress the right to levy and collect income taxes. For federal income tax purposes, the Internal Revenue Code defines 'gross income' as [...]

Statement of Financial Accounting Standard No. 130 (SFAS 130) was released in 1997 which required publicly traded companies to separately report comprehensive income in the financial statements. SFAS 130 prescribed three alternative formats for the presentation without mandating any one specific format. SFAS 130 also required certain details of comprehensive income to be displayed prominently in the financial statements. The current study examined the presentation of comprehensive income by a sample of companies traded on the NASDAQ market to determine the predominant method of presentation among these companies, five years after SFAS 130 became effective. Results of the examination of one hundred annual reports showed that a majority of the sampled companies used the third approach, which was to present comprehensive income as part of the Statement of Stockholders' Equity, as against the first two approaches that favored presentation of comprehensive income on the face of the Income Statement or in a separate statement. Further, the paper also discusses some ancillary findings pertaining to the presentation of the details of comprehensive income.

Diffuse optical tomography (DOT) is a non-invasive imaging technique utilizing multi-scattered light at visible and infrared wavelengths to detect anomalies in tissues. However, the DOT image reconstruction is based on solving the inverse problem, which requires massive calculations and time. In this article, for the first time, to the best of our knowledge, a simple, regression-based cascaded feed-forward deep learning neural network is derived to solve the inverse problem of DOT in compressed breast geometry. The predicted data is subsequently utilized to visualize the breast tissues and their anomalies. The dataset in this study is created using a Monte-Carlo algorithm, which simulates the light propagation in the compressed breast placed inside a parallel plate source-detector geometry (forward process). The simulated DL-DOT system's performance is evaluated using the Pearson correlation coefficient (R) and the Mean squared error (MSE) metrics. Although a comparatively smaller dataset (50 nos.) is used, our simulation results show that the developed feed-forward network algorithm to solve the inverse problem delivers an increment of ∼30% over the analytical solution approach, in terms of R. Furthermore, the proposed network's MSE outperforms that of the analytical solution's MSE by a large margin revealing the robustness of the network and the adaptability of the system for potential applications in medical settings.

Recent developments in machine learning (ML) methods demonstrate unparalleled potential for application in the spine. The ability for ML to provide diagnostic faculty, produce novel insights from existing capabilities, and augment or accelerate elements of surgical planning and decision making at levels equivalent or superior to humans will tremendously benefit spine surgeons and patients alike. In this review, we aim to provide a clinically relevant outline of ML-based technology in the contexts of spinal deformity, degeneration, and trauma, as well as an overview of commercial-level and precommercial-level surgical assist systems and decisional support tools. Furthermore, we briefly discuss potential applications of generative networks before highlighting some of the limitations of ML applications. We conclude that ML in spine imaging represents a significant addition to the neurosurgeon's armamentarium—it has the capacity to directly address and manifest clinical needs and improve diagnostic and procedural quality and safety—but is yet subject to challenges that must be addressed before widespread implementation.

AbstractThe methods used for finding the best value out of the bulk amount of data available in a sample are known as optimization techniques. Different types of such techniques are used to make machines more efficient.FACTS devices play a vital role to compensate for the reactive power of the power system by means of improving the voltage profile of the system, as the reactive power of a power transmission system directly depends upon the magnitude of the voltage. The Newton-Raphson (NR) load flow method is used for IEEE 14 bus with its standard bus and branch data. The optimal size and location of G-UPFC found out by using ant colony optimization (ACO) is inserted in the different IEEE bus systems.

AbstractThe existing approach of an electrical board representative manually reading the energy metre and issuing invoices to the owner has been shown to be inefficient and prone to human mistakes and possibly misconduct. Indian energy users are also afflicted by a lack of current information and understanding. Using the IC ACS71020, this study presents a customized IoT-based Advanced Smart Energy Meter infrastructure with remote and local logging and monitoring of electrical parameters. The meter also has provisions for connections to both web and cellular internet using ESP8266 and GSMsim800a. The elimination of human interaction and the rapid updating of information makes the consumer’s life easier and more efficient. Data is also shown on an OLED screen and stored on an SD Card / Flash Memory, allowing access to a local server.

ABSTRACTThe Forming limit diagram is an important tool in metal forming processes, as it indicates the failure limits for ductile damage and onsite necking. Forming of micro-thin metal sheets (thickness less than 100 microns) is more difficult and requires more precision. This type of miniaturisation in forming process with the components produced with dimensions up to few millimetres is defined as a micro-forming. There are many differences in the properties of materials and physics of process when macro process is converted to micro. In this work, an experimental test of thin alpha brass sheets of 40 µm and 90 µm with different orientations to rolling directions (0º, 45º, 90º) was performed to determine the forming limit curves. Hemispherical punching test designed for micro forming is performed according to ASTM-2218-14 standard test using sample of Uni-Axial, Intermediate Uni-Axial, Bi-Axial, Intermediate Bi-Axial and Plane Strain paths to obtain limit strains. Explicit dynamic numerical analysis with Abaqus platform is used to model micro-forming process and forming limit curves are plotted. Numerical results have been validated with experimental results.

Though several are the in-roads that have been made towards achieving design-for-manufacturability (DFM) and design-for-assembly (DFA), speaking of some of the crucial issues associated with concurrent engineering, yet very few comprehensive blueprints exist that speak of a near-complete concurrent engineering environment. This could mainly be attributed to the multifarious versions of how to successfully setup a concurrent engineering environment for today's ever changing engineering scenario. An operational concurrent engineering environment needs to be addressed in its totality or near-totality. This paper is one such venture.

Following the seminal work of Aleskovskii (1) and Suntola (2) in establishing the field of atomic layer deposition (ALD) science, the subject has rapidly expanded in both academic and commercial [...]

Diagnosing primary central nervous system lymphoma (PCNSL) frequently requires neurosurgical biopsy due to nonspecific radiologic features and the low yield of cerebrospinal fluid (CSF) studies. We characterized the clinical evaluation of suspected PCNSL (N = 1007 patients) and designed a rapid multiplexed genotyping assay for MYD88, TERT promoter, IDH1/2, H3F3A, and BRAF mutations to facilitate the diagnosis of PCNSL from CSF and detect other neoplasms in the differential diagnosis. Among 159 patients with confirmed PCNSL, the median time to secure a diagnosis of PCNSL was 10 days, with a range of 0 to 617 days. Permanent histopathology confirmed PCNSL in 142 of 152 biopsies (93.4%), whereas CSF analyses were diagnostic in only 15/113 samplings (13.3%). Among 86 archived clinical specimens, our targeted genotyping assay accurately detected hematologic malignancies with 57.6% sensitivity and 100% specificity (95% confidence interval [CI]: 44.1% to 70.4% and 87.2% to 100%, respectively). MYD88 and TERT promoter mutations were prospectively identified in DNA extracts of CSF obtained from patients with PCNSL and glioblastoma, respectively, within 80 minutes. Across 132 specimens, hallmark mutations indicating the presence of malignancy were detected with 65.8% sensitivity and 100% specificity (95% CI: 56.2%-74.5% and 83.9%-100%, respectively). This targeted genotyping approach offers a rapid, scalable adjunct to reduce diagnostic and treatment delays in PCNSL.

The SEC recognizes the integral role that an audit committee plays in ensuring the fairness of financial reporting by publicly traded companies. In the past, the SEC did not require [...]

Primary central nervous system (CNS) lymphoma (PCNSL) is an aggressive intracranial malignant neoplasm in adults whose incidence in the United States is about 15% of that of glioblastoma. [1] Tumor [...]

Physical comfort and emotional support are principal components of patient-centred care in healthcare delivery, however, they are not given much importance by researchers in India. Furthermore, previous studies done in western countries have given some insights on physical comfort and emotional support. This study precisely aimed to fill these observed gaps by first focusing on the perception of healthcare professionals from the tertiary healthcare centres in Chennai and secondly in understanding the perception of patients from the same setup of hospitals in the major factors of physical comfort and emotional support. Finally, the impact of these two factors on the confidence and trust of healthcare professionals. The results from this study indicated that 'assistance with daily activity' followed by 'emotional support' have influence on confidence and trust of healthcare professionals. In addition, the results exerted strong evidence that patient needs explanation on the medications in the language they can understand, environmental comfort and emotional support. Furthermore, the study provides understandings into the research and managerial implications of such findings.

Graphical Abstract

Taking advantage of the C2-symmetry of the antitumor naturally occurring disorazole B1molecule, a symmetrical total synthesis was devised with a monomeric advanced intermediate as the key building block, whose three-step conversion to the natural product allowed for an expeditious entry to this family of compounds. Application of the developed synthetic strategies and methods provided a series of designed analogues of disorazole B1, whose biological evaluation led to the identification of a number of potent antitumor agents and the first structure–activity relationships (SARs) within this class of compounds. Specifically, the substitutions of the epoxide units and lactone moieties with cyclopropyl and lactam structural motifs, respectively, were found to be tolerable for biological activities and beneficial with regard to chemical stability.

Objective: To examine the effect of race in driving performance and behavior prospectively among cognitively normal older adults. Methods: Cognitively normal participants (Clinical Dementia Rating 0), ≥ 65 years of age (n= 177) were selected from prospective, longitudinal studies at the Knight Alzheimer Disease Research Center at Washington University. Self-reported driving behavior (Driving Habits Questionnaire) and driving performance (road test) were annually assessed. Daily driving behavior data were collected using the Driving Real World In-Vehicle Evaluation System (DRIVES). Baseline differences between African Americans and Caucasians were tested using ttests and general linear models. Amyloid imaging and cerebrospinal fluid Alzheimer disease (AD) biomarkers were compared across groups. Linear mixed models examined change in daily driving behavior over time. Survival analyses tested time to a marginal or fail rating on the road test. Results: There were no differences between African Americans (n= 34) and Caucasians (n= 143) in age, sex, education, or vascular risk factors. Baseline self-reported driving behavior and road test performance were largely similar for both races. Longitudinal analyses using the DRIVES data aggregated monthly showed that African Americans had a greater reduction in number of trips made per month, miles driven per month, and trips with aggressive behavior compared to Caucasians. These effects remained after controlling for AD biomarkers, age, education, and sex. Conclusions: In this sample of cognitively normal older adults, African Americans had a greater reduction of daily driving behavior compared to Caucasians. Observed racial differences may reflect differences in environmental/social factors, changes in cognition, and/or physical functioning.

Byline: M. Ganesh, S. Shah, D. Parikh, P. Choudhary, V. Bhaskar Background and Objectives: the purpose of this study was to clinically evaluate and compare the efficacy of 'Brush Buddies' [...]

Byline: M. Ganesh, S. Tandon, B. Sajida Muscular activity of the lips, cheeks, and the tongue are important factors, which not only guide the occlusal development but also affect the [...]

In this work, a new patch-based texture synthesis scheme with orthogonal polynomials model coefficients is presented. The proposed scheme has four phases. In the first phase, a block matching technique that identifies a best match, to synthesis in the output image of bigger size is designed in terms of ordered orthogonal polynomials model coefficients. In case of successful match of block, called patch-hit, the proposed scheme finds candidate blocks with triangular search, in the next phase. In the patch selection phase, the proposed scheme considers a subset of orthogonal polynomials model coefficients among the blocks, for the purpose of synthesis which consumes less memory and time. This synthesised output is smoothened in the final phase, by preserving the low level contents between the synthesised patches. The performance of the proposed scheme is measured with energy, contrast, correlation, homogeneity and entropy between the original and synthesised images and is also compared with existing texture synthesis schemes. The results are encouraging.

Catalytic wet air oxidation (CWAO) is a prospective method for the treatment of distillery effluents. In this work, the biodegradability of biomethanated distillery spent wash (biochemical oxygen demand (BOD5) = 8100 and chemical oxygen demand (COD) = 40 000 mg/L) was improved by oxidation over a ferrous sulfate catalyst. The homogeneous CWAO process was optimized by investigating the effects of reaction variables, such as temperature (150–225 °C), oxygen partial pressure (0.69–2.07 MPa), and catalyst loading (16–48 mg/L). After oxidation at T= 175 °C for 1 h, adsorption over activated carbon (loading 5%) was performed at ambient temperature. As a result, a 73% reduction in COD and a substantial increase in the BOD5/COD ratio (from 0.2 to 0.45) was observed. This ratio increased further to 0.52 when anaerobic digestion was performed, using 1% acclimatized biomass. For every cubic meter of wastewater, 1.1 N m3of biogas was formed (69% methane). After a final polishing step by aerobic treatment, BOD5/COD = 0.58 and 91% COD was destroyed. Clearly, this work has provided a useful solution to the effective pretreatment and valorization of biomethanated distillery wastewaters. Lastly, we employed a two-step power-law model to describe the kinetics of COD conversion.

The study aims to evaluate the tensile behavior of sisal glass-reinforced polymer composites with varying geometric irregularities. Composite laminates were fabricated using a hand layup technique, incorporating sisal fiber woven reinforcement and ortho-phthalic unsaturated polyester resin. The laminates, configured with 7 and 9 layers, were subjected to tensile testing with and without 6 mm and 12 mm diameter central holes and double holes spaced at 6.2 mm, 12 mm, and 48 mm intervals. The tensile tests were conducted using an electromechanical test system, and the results were analyzed to determine the ultimate tensile strength, modulus of elasticity, and failure strain for each specimen type. The findings revealed significant differences in tensile strength depending on the presence and size of the holes. Specimens with central holes exhibited a reduction in tensile strength, with the extent of strength reduction dependent on the hole diameter. Larger holes resulted in more severe stress concentrations, leading to greater strength degradation. Double-hole specimens showed similar strength reduction patterns, with closer spacing exacerbating the stress concentration effects. The residual strength ratio (RSR) for different configurations conformed to expected values for fiber-reinforced composites with circular hole-type defects. The study underscores the critical impact of geometric irregularities on the mechanical performance of sisal glass-reinforced polymer composites. These findings can guide the development of design strategies to mitigate the adverse effects of stress concentrators, thereby enhancing the reliability and durability of these materials in practical applications.

Received on October 16, 1998. Final version was accepted on November 22, 1999. The current research hypothesized that if the incumbent audit firms presented themselves effectively to their clients, it [...]

Hybrid metal matrix composites are being widely investigated for use in light weight, high strength applications. In the present study, Aluminium alloy Al7075 was reinforced with B4C and TiO2 at 4% and 2% weight fractions respectively. The powders of the reinforcements were ball milled for uniform distribution in the Al matrix, and later fabricated by stir casting technique primarily due to simplicity and economy of the method. The specimen were prepared as per ASTM standards and later subjected to hardness, double shear, wear and impact tests and the results were compared with that of pure aluminium specimen fabricated by the same method. The hardness, shear strength, impact strength of the composite were found to be higher than pure aluminium by 4.97%, 32.28% ands 6.41% respectively.

Amyloid formation of α-synuclein (α-Syn) and its familial mutations are directly linked with Parkinson’s disease (PD) pathogenesis. Recently, a new familial α-Syn mutation (A53E) was discovered, associated with an early onset aggressive form of PD, which delays α-Syn aggregation. When we overexpressed wild-type (WT) and A53E proteins in cells, showed neither toxicity nor aggregate formation, suggesting merely overexpression may not recapitulate the PD phenotype in cell models. We hypothesized that cells expressing the A53E mutant might possess enhanced susceptibility to PD-associated toxicants compared to that of the WT. When cells were treated with PD toxicants (dopamine and rotenone), cells expressing A53E showed more susceptibility to cell death along with compromised mitochondrial potential and an increased production of reactive oxygen species. The higher toxicity of A53E could be due to more oligomers being formed in cells as confirmed by a dot blot assay using amyloid specific OC and A11 antibody and using an in vitroaggregation study. The cellular model presented here suggests that along with familial mutation, environmental and other cellular factors might play a crucial role in dictating PD pathogenesis.

The involvement of α-synuclein (α-Syn) amyloid formation in Parkinson’s disease (PD) pathogenesis is supported by the discovery of α-Syn gene (SNCA) mutations linked with familial PD, which are known to modulate the oligomerization and aggregation of α-Syn. Recently, the A53V mutation has been discovered, which leads to late-onset PD. In this study, we characterized for the first time the biophysical properties of A53V, including the aggregation propensities, toxicity of aggregated species, and membrane binding capability, along with those of all familial mutations at the A53 position. Our data suggest that the A53V mutation accelerates fibrillation of α-Syn without affecting the overall morphology or cytotoxicity of fibrils compared to those of the wild-type (WT) protein. The aggregation propensity for A53 mutants is found to decrease in the following order: A53T > A53V > WT > A53E. In addition, a time course aggregation study reveals that the A53V mutant promotes early oligomerization similar to the case for the A53T mutation. It promotes the largest amount of oligomer formation immediately after dissolution, which is cytotoxic. Although in the presence of membrane-mimicking environments, the A53V mutation showed an extent of helix induction capacity similar to that of the WT protein, it exhibited less binding to lipid vesicles. The nuclear magnetic resonance study revealed unique chemical shift perturbations caused by the A53V mutation compared to those caused by other mutations at the A53 site. This study might help to establish the disease-causing mechanism of A53V in PD pathology.

Although there is no mandate by the IRS to participate in the federal e-filing program, the number of returns filed electronically has grown dramatically over the past few years. According [...]