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While the burden of dementia is increasing in low- and middle-income countries, there is a low rate of diagnosis and paucity of research in these regions. A major challenge to study dementia is the limited availability of standardised diagnostic tools for use in populations with linguistic and educational diversity. The objectives of the study were to develop a standardised and comprehensive neurocognitive test battery to diagnose dementia and mild cognitive impairment (MCI) due to varied etiologies, across different languages and educational levels in India, to facilitate research efforts in diverse settings.
A multidisciplinary expert group formed by Indian Council of Medical Research (ICMR) collaborated towards adapting and validating a neurocognitive test battery, that is, the ICMR Neurocognitive Tool Box (ICMR-NCTB) in five Indian languages (Hindi, Bengali, Telugu, Kannada, and Malayalam), for illiterates and literates, to standardise diagnosis of dementia and MCI in India.
Following a review of existing international and national efforts at standardising dementia diagnosis, the ICMR-NCTB was developed and adapted to the Indian setting of sociolinguistic diversity. The battery consisted of tests of cognition, behaviour, and functional activities. A uniform protocol for diagnosis of normal cognition, MCI, and dementia due to neurodegenerative diseases and stroke was followed in six centres. A systematic plan for validating the ICMR-NCTB and establishing cut-off values in a diverse multicentric cohort was developed.
A key outcome was the development of a comprehensive diagnostic tool for diagnosis of dementia and MCI due to varied etiologies, in the diverse socio-demographic setting of India.
Orientalism was, and in modified ways continues to be, a capacious, supple and changing discursive system that enables Anglo-European writers to explain and to manage the encounters between themselves and the peoples of lands ranging from Turkey, Egypt, Persia, and India to China and Japan. Since these peoples, their lives, their manufactures and their world-views were so different from each other (as in fact were the different westerners who engaged them), we must begin by recognizing that Orientalism is a discourse of singular power, one that manufactures an “Orient” even as it brings different peoples into view.
This paper reports on an ultra-wideband low-noise distributed amplifier (LNDA) in a transferred-substrate InP double heterojunction bipolar transistor (DHBT) technology which exhibits a uniform low-noise characteristic over a large frequency range. To obtain very high bandwidth, a distributed architecture has been chosen with cascode unit gain cells. Each unit cell consists of two cascode-connected transistors with 500 nm emitter length and ft/fmax of ~360/492 GHz, respectively. Due to optimum line-impedance matching, low common-base transistor capacitance, and low collector-current operation, the circuit exhibits a low-noise figure (NF) over a broad frequency range. A 3-dB bandwidth from 40 to 185 GHz is measured, with an NF of 8 dB within the frequency range between 75 and 105 GHz. Moreover, this circuit demonstrates the widest 3-dB bandwidth operation among all reported single-stage amplifiers with a cascode configuration. Additionally, this work has proposed that the noise sources of the InP DHBTs are largely uncorrelated. As a result, a reliable prediction can be done for the NF of ultra-wideband circuits beyond the frequency range of the measurement equipment.
Age-related macular degeneration (AMD), a retinal degenerative disease that results in a continuous degeneration of photoreceptors in the retina, which eventually leads to complete blindness. One approach to combat AMD is through the use of artificially implantable photodetectors that are physically placed on the retina. Interestingly, 2D materials such as photosensitive and semiconducting molybdenum disulfide (MoS2) and electrically conducting graphene have recently received tremendous promise due to their unique photonic and optoelectronic properties and their potential in various types of micro and nano-devices. In this study, a highly biocompatible 2D graphene-MoS2 photodetectors on a flexible polyimide substrate were designed, fabricated using inkjet printing to form photosensitive pixels and tested as a function of photo intensity and strain. The inkjet printed 2D heterostructure devices were photoresponsive and the photocurrent scaled proportionally with the incident light intensity, exhibiting a photoresponsivity R ∼ 0.30 A/W at room temperature. The strain-dependent measurements of photocurrent with bending showed a photocurrent of Iph ∼ 1.16 μA with strain levels for curvature up to ∼ 0.262 cm-1. Inkjet printed graphene and MoS2 inks were also characterized using techniques such as Raman Spectroscopy, Photoluminescence (PL) and Scanning Electron Microscopy (SEM).
The presence of a direct optical bandgap in the transition metal dichalcogenide (TMD) layers leads to promising applications in optoelectronic devices such as phototransistors and photodetectors. These devices are commonly fabricated using few-layer and monolayer MoS2 sheets obtained using mechanical exfoliation or chemical vapor deposition techniques. The hybrid structure of quantum dots (QDs) and 2D materials has been investigated to provide outstanding properties for various applications. Herein we report the fabrication of a hybrid QDs/MoS2 photodetector consisting of graphene quantum dots (GQDs) and multilayer MoS2 sheets. The hybrid GQDs and MoS2 films are characterized by atomic force microscopy (AFM); additionally, the I-V characteristics are measured by two-point probe station.
OBJECTIVES/SPECIFIC AIMS: Improving human papillomavirus (HPV) vaccination rates ultimately decreases the morbidity and mortality of HPV-associated diseases. A school-based program was piloted in the Rio Grande City Consolidated Independent School District (RGCCISD) to increase HPV vaccination. METHODS/STUDY POPULATION: We assessed baseline HPV vaccination; surveyed 622 parents of eligible children aged ≥9 years; and piloted and developed a school-based HPV education and vaccination program in 1 middle school in 2017 and 4 additional middle schools in 2018. The parent survey included (1) demographic information, (2) an assessment of parental knowledge about the HPV vaccine, and (3) information about their children and HPV vaccine experience. Results of the parent survey and pilot program are in progress. RESULTS/ANTICIPATED RESULTS: As of 9/1/2016, 20.4% of the 7527 RGCCISD eligible students (≥9 years) had completed the HPV vaccine. Baseline completion rates were higher for RGCCISD students aged 12–14 years compared with students aged 9–11 and ≥15 years (28.4% vs. 16.5%). Baseline completion rates for RGCCISD adolescents were substantially lower than those reported in NIS-Teen and for Texas (42% females and 28% males for NIS-Teen vs. 41% and 24% for the state of Texas). DISCUSSION/SIGNIFICANCE OF IMPACT: Initial results show that engagement with key stakeholders is important and schools are a great venue for delivering and increasing HPV vaccination.
OBJECTIVES/SPECIFIC AIMS: Long interspersed element-1s (L1s) are autonomous, mobile elements that are able to copy and insert themselves throughout the genome with their own reverse transcriptase and endonuclease. These elements make up 17% of the human genome with over 500,000 copies, though the vast majority of L1s are defective with only a few dozen potentially responsible for L1 activity. Full-length L1s have the potential to contribute to mutagenesis through random insertion and increased genetic instability. Here we set out to study L1 expression at the specific loci level in bone marrow-derived stem cells (bmSCs) and adipose-derived stem cells (ASCs) and compare the levels of expression from ASCs from donor patients who are young and lean, obese, and old. Our hypothesis is that L1-related damage may contribute to mutation and inflammation that alters the function of these stem cells throughout the life of an individual. METHODS/STUDY POPULATION: ASCs and bmSCs were isolated from patient donors. The following samples were collected: ASCs from 3 young (under the age of 59) and lean (BMI<30) patients, ASCs from 3 older patients (over the age of 59), ASCs from 3 patients with BMI>30, and bmSCs from 4 young and lean patients. Cytoplasmic RNA from the cell populations was isolated and sequenced by RNA-Seq from the cell populations. Using our recently developed bioinformatics pipeline, we set out to quantify L1 expression and identify the few culprit L1s at specific loci that are actively transcribing to RNA in the ASC and bmSC samples. RESULTS/ANTICIPATED RESULTS: Here we provide proof of concept with the application of this novel method in characterizing full-length expressed L1s at the specific loci level in ASCs and bmSCs. We identified L1 loci that are commonly expressed in these cell types and observed an increase in L1 expression in the obese and old ASC cells compared with the young, lean ASCs and bmSCs. DISCUSSION/SIGNIFICANCE OF IMPACT: ASCs hold the promise of broad application in the biomedical field including regenerative treatment. There are reports that ASCs cultivated from older and obese donors are less effective in regenerative treatments. By demonstrating an increased expression of the mutagenic L1 element in ASCs from obese and old donors, this study provides further evidence suggesting the preferable use of ASCs from young and lean donors for regenerative therapies. These studies will also help us to understand the potential contribution of L1 expression to loss of stem cell function during the aging process.
Using kerf-free wafering technologies material losses in semiconductor manufacturing processes can be reduced drastically. By the use of externally applied stress, crystalline materials can be separated along crystal planes with clearly defined thickness. Nevertheless, during this process striations caused by the crack propagation occur. These crack growth features are river and Wallner lines. In this work, we demonstrate a process for spalling that scales favorably for large-area semiconductor substrates with a diameter up to 300 mm. To get rid of the crack growth features, a laser-conditioning process with a high numerical aperture at photon energies below the material bandgap energy, using multi-photon effects is utilized. The process affords a surface roughness Ra after spalling of <1 µm.
Concertina wire is the most widespread form of vegetationin Kashmir today. It grows everywhere, including in the mind.
Much of the extraordinary violence that Kashmir has seen over the last two decades and more has been documented by Kashmiri and international human rights groups, civil society activists and journalists. However, the effect such long-term violence has had in the forging of political subjectivities has not become central to scholarship on contemporary Kashmir. That Kashmir has become a conflict zone, with periods of intense violence followed by months of relative calm, is acknowledged by all, but commentators rarely factor in the effects of such prolonged instability and suffering on the political and social attitudes of Kashmiris today. Analysts tend to focus on political developments and incidents of violence in the moment, and even those who recognize that there is an entire generation and more whose only sense of ‘normality’ is of a conflict-ridden Kashmir, make this observation only to set it aside. Noticeably absent from such analyses is a sense of traumatized lives under siege, or of the way in which the pressure of events transforms subjectivities and repurposes political priorities over time.
But loss and traumatic experiences are now woven into the fabric of Kashmiri lives: everyone has first-hand accounts of violence to offer and people often call attention to their experiences as they explain their political positions. I have suggested elsewhere that creative texts produced in times of conflict offer a way of addressing crucial lacunae in our understanding of Kashmir and Kashmiris, for they illuminate not only the political and ideological issues at stake, but also states of being precipitated by violence, loss and resistance. For instance, poems from conflict zones are sure guides to the intensity of feelings that result from prolonged conflicts, and which, over time, play a significant role in the perpetuation of the conflict. This can be a matter of idiom and tone, for the performative elements of a poem emphasize emotional and psychological intensities sidelined in the affectively-neutral tones of news reportage, policy documents, or standard historiography (Kaul, 2015). As Muzamil Jaleel noted early in the period of conflict, Kashmiri poetry had become a crucial medium for the articulation of trauma and of protest in a time when censorship and fear made writing in prose dangerous (2002).
Chemically exfoliated two-dimensional (2D) materials have shown promise in a variety of applications such as thin film transistors and photovoltaic devices. Here, we present a scalable method for preparing black phosphorus membranes via direct liquid-phase exfoliation of the bulk crystal in organic solvents. The black phosphorus sheets are characterized by Raman and Photoluminescence (PL) spectroscopy, and optical microscopy. The properties of these chemically exfoliated black phosphorus was compared to mechanically exfoliated nanomembranes. The liquid-phase exfoliation nonetheless yields the potential for large-area scalability. Our results highlight the important aspects of forming solution dispersions of 2D black phosphorus which can subsequently be the stepping stone for future work on the ink-jet printing of such dispersions over a wide range of substrates.
Two-dimensional (2D) materials are very promising with respect to their integration into optoelectronic devices. Monolayer tungsten diselenide (WSe2) is a direct-gap semiconductor with a bandgap of ∼1.6eV, and is therefore a complement to other two-dimensional materials such as graphene, a gapless semimetal, and boron nitride, an insulator. The direct bandgap distinguishes monolayer WSe2 from its bulk and bilayer counterparts, which are both indirect gap materials with smaller bandgaps. This sizable direct bandgap in a two-dimensional layered material enables a host of new optical and electronic devices. In this work, a comprehensive analysis of the effect of optical excitation on the transport properties in few-layer WSe2 is studied. Monolayer WSe2 flakes from natural WSe2 crystals were transferred onto Si/SiO2 (270nm) substrates by mechanical exfoliation. The flakes were observed under an optical microscope. A FET based on mechanically exfoliated WSe2 was fabricated using photolithography with Molybdenum as metal contact and Silicon as back gate and the electronic properties were measured in a wide range of temperatures. The mobility of our device was found to be 0.2 cm /V-S at room temperature. The schottky barrier height was found to decrease from 80 meV to 25 meV as the gate voltage increases.
Two-dimensional layered materials, materials with weak out-of-plane van der Waals bonding and strong in-plane covalent bonding, have attracted special attention in recent years since the isolation and characterization of monolayer graphite, the graphene. The electrical bandgap in Transition Metal Di-Chalcogenides (TMDCs), non-existent in graphene, make them a good alternative family of materials for novel electronic and optoelectronic applications. 2H- MoS2, one of the most stable TMDCs, has been extensively studied, including the synthesis methods, and its potential applications in photodetection. The chemical vapor deposition (CVD) synthesis method has increased its potential over the years. The advantages of this method are scalability compared to micromechanical exfoliation, common process used in research laboratories, and the maintenance of the quality and intrinsic properties of the material compared to the liquid exfoliation methods. In this work, we synthesized high quality pristine 2H-MoS2 via atmospheric pressure chemical vapor deposition (APCVD) by vapor phase reaction of MoO3 and S powder precursors. The samples were characterized via Raman and photoluminescence (PL) spectroscopy and compared to mechanically exfoliated MoS2 crystal by measuring the full-width half maxima (FWHM) of monolayer and few-layer mesoscopic flakes. In addition, the CVD synthesized single and few-layered MoS2 domains were transferred to different substrates using a high yield process, including a flexible substrate, preserving the quality of the material. Finally, and mechanically exfoliated MoS2 two-terminal photodetector was designed, fabricated, and measured. Demonstrating thus the capability of heterostructure fabrication and the quality of our synthesis and device fabrication process.
In this work, a new method is presented to synthesize graphene-C60 hybrid materials using an electrophoretic deposition technique to study the graphene-C60 interactions. Electronic measurements of the structure were conducted before and after the attachment of C60 clusters at different applied voltages on graphene devices. The assembled clusters of C60 on mechanically exfoliated graphene were investigated using Raman Spectroscopy and Scanning Electron Microscopy (SEM), which reveal a uniform morphology of C60 on graphene. The results indicate that graphene-C60 hybrids are excellent electron accepting/charge transporting materials which can provide an effective route to facilitate the application of these hybrids in electronic or opto-electronic device platforms.
In this work, we demonstrate optical and electrical transport properties of chemically exfoliated WS2 in cyclohexanone/ terpineol solvent using different sonication times. High electrical conductivity of WS2 nanodispersions was observed when appropriate amount of voltage was applied indicating their semi-conductive behavior. Surface morphology of WS2 nanodispersions sonicated at different times were studied using optical microscopy. Optical bandgap of WS2 nanodispersions were determined from optical absorbance spectrum. Inkjet printing was used to demonstrate uniform distribution of WS2 nanosheets and their precise and large scale printability. These dispersions indicate the potential of WS2 in various optoelectronic and semiconducting device applications.
In this paper, we have developed composites with Poly-methyl methacrylate (PMMA) as the matrix material, while transition metal dichalcogenides (TMDCs), MoS2 and WS2 and graphite served as the filler materials. The PMMA was chosen as the matrix material due to its low-cost, wide availability, as well as its promising mechanical and optical properties for enabling opto-electro-mechanical sensing devices. The amount of filler material used ranged from 100 mg/ml up to 400 mg/ml. With the aid of designed fixtures we related the electrical properties of the PMMA-based composite sensors to the degree of strain or deformation. Additionally, a nanoindenter was used to measure the modulus of elasticity, with values as low as 2 GPa and as high as 20 GPa for the graphite composites, and hardness values which ranged from 0.1 GPa to ∼ 1.6 GPa.
Two dimensional (2D) thin transition metal dichalcogenides are being widely investigated for optoelectronics applications. Here, we report on the interfacial study of WSe2 with photo-absorber materials for efficient charge transport using Kelvin Probe Force Microscopy (KPFM) for solar cell applications. The WSe2 in these experiments was synthesized using Chemical Vapor Deposition (CVD) with a WO3 powder and Se pellets as the precursors, where the selenium was placed upstream in an Ar carrier gas within the furnace at a temperature zone of 260-270°C. For the interfacial analysis, nanoscale KPFM measurements show an average surface potential of 125 meV for the CVD synthesized WSe2 flakes. KPFM measurements signify that a thin layer of WSe2 can be used to suppress back recombination of carriers between the electron transport layer (ETL) and the absorber layer. A proper band alignment between ETL and absorber layer helps to increase the overall device performance, which we will elaborate upon in this work. Capacitance-voltage and capacitance-frequency measurements were measured to study the role of defects.