Strategic fabrication of efficient photo-responsive semiconductor electronic diode-devices by Bovine Serum Albumin protein-based Cu(II)-metallohydrogel scaffolds.

Bovine Serum Albumin protein-based two fascinating functional self-healing Cu(II) metallohydrogel scaffolds (MD1 and MD2) have been studied for the development of metal-semiconductor junction based Schottky diode device. Multiple metal-semiconductor (MS) junction devices, offering the sandwich-like configuration of Indium tin oxide (ITO)/ metallogel/Aluminium (Al), have been made-up to investigate the electrical properties of the synthesized metallohydrogel materials. Optical characterizations including optical band gap measurement have been carried out using Tauc's equation for both the metallohydrogels. The current-voltage (I-V) characteristics of just made-up devices are studied under irradiation and non- irradiation conditions to explore the electrical features through investigating the charge transport phenomenon. The electrical conductivity gets estimated as 3.13 × 10-5 S.m-1 and 2.69 × 10-5 S.m-1 for MD1 and MD2 under dark condition, and 11.06 × 10-5 S.m-1 and 5.99 × 10-5 S.m-1 for MD1 and MD2, respectively, in photo-irradiation. The measured optical and electrical properties of MD1 and MD2 metallohydrogels are thoroughly investigated and the data indicates that MD1 and MD2 metallohyrogels are semiconducting in nature with excellent photo-responsive behaviour. Moreover, the representative I - V characteristic of the MD1 and MD2 metallohydrogels at both irradiation and non-irradiation conditions represents the nonlinear rectifying behaviour, a typical signature for Schottky diode (SD).

Dynamic eco-efficiency evaluation of the semiconductor industry: a sustainable development perspective.

Serious environmental problems have accompanied remarkable global economic growth for decades. To assist managers in the semiconductor industry with economic and environmental management, this study executes DuPont analysis to examine economic impacts from the effective implementation of sustainability initiatives. We propose a two-stage process including economic development efficiency and environmental protection efficiency through the dynamic data envelopment analysis (DDEA) to reflect the characteristics of eco-efficiency. Through DuPont analysis, the main finding shows the potential improvement in firms' return on equity (ROE) by efficiently utilizing assets to generate sales quickly.Relative to economic development efficiency, the firms show lower scores and higher standard deviations in the environmental protection ability, thus denoting a large gap in the level of environmental protection production technology. The findings in this study reveal that the financial foundations and sustainable development of industries should be improved simultaneously even though specific levels of semiconductor industrial eco-efficiency improvement vary among companies in Taiwan.

Current Status and Future Prospects of Semiconductor Quantum Dots in Botany.

The development of botanical applications of nanomaterials has produced a new generation of technologies that can profoundly impact botanical research. Semiconductor quantum dots (QDs) are an archetype nanomaterial and have received significant interest from diverse research communities, owing to their unique and optimizable optical properties. In this review, we describe the most recent progress on QD-based botanical research and discuss the uptake, translocation, and effects of QDs on plants and the potential applications of QDs in botany. A critical evaluation of the current limitations of QD technologies is discussed, along with the future prospects in QD-based botanical research.

Bithiazole: An Intriguing Electron-Deficient Building for Plastic Electronic Applications.

The heterocyclic thiazole unit has been extensively used as electron-deficient building block in π-conjugated materials over the last decade. Its incorporation into organic semiconducting materials is particularly interesting due to its structural resemblance to the more commonly used thiophene building block, thus allowing the optoelectronic properties of a material to be tuned without significantly perturbing its molecular structure. Here, we discuss the structural differences between thiazole- and thiophene-based organic semiconductors, and the effects on the physical properties of the materials. An overview of thiazole-based polymers is provided, which have emerged over the past decade for organic electronic applications and it is discussed how the incorporation of thiazole has affected the device performance of organic solar cells and organic field-effect transistors. Finally, in conclusion, an outlook is presented on how thiazole-based polymers can be incorporated into all-electron deficient polymers in order to obtain high-performance acceptor polymers for use in bulk-heterojunction solar cells and as organic field-effect transistors. Computational methods are used to discuss some newly designed acceptor building blocks that have the potential to be polymerized with a fused bithiazole moiety, hence propelling the advancement of air-stable n-type organic semiconductors.

Energy-Efficient Neuromorphic Classifiers.

Neuromorphic engineering combines the architectural and computational principles of systems neuroscience with semiconductor electronics, with the aim of building efficient and compact devices that mimic the synaptic and neural machinery of the brain. The energy consumptions promised by neuromorphic engineering are extremely low, comparable to those of the nervous system. Until now, however, the neuromorphic approach has been restricted to relatively simple circuits and specialized functions, thereby obfuscating a direct comparison of their energy consumption to that used by conventional von Neumann digital machines solving real-world tasks. Here we show that a recent technology developed by IBM can be leveraged to realize neuromorphic circuits that operate as classifiers of complex real-world stimuli. Specifically, we provide a set of general prescriptions to enable the practical implementation of neural architectures that compete with state-of-the-art classifiers. We also show that the energy consumption of these architectures, realized on the IBM chip, is typically two or more orders of magnitude lower than that of conventional digital machines implementing classifiers with comparable performance. Moreover, the spike-based dynamics display a trade-off between integration time and accuracy, which naturally translates into algorithms that can be flexibly deployed for either fast and approximate classifications, or more accurate classifications at the mere expense of longer running times and higher energy costs. This work finally proves that the neuromorphic approach can be efficiently used in real-world applications and has significant advantages over conventional digital devices when energy consumption is considered.

Dados Preliminares do Valor Prognóstico de um Novo Protocolo deCintilografia Miocárdica Ultrarrápido e com Menos Radiação emGamacâmara CZT / Preliminary Data on the Prognostic Value of a New Protocol of Ultra-fast Myocardial Scintigraphy with Less Radiation in CZT Gamma Camera

A cintilografia miocárdica de perfusão (CMP) é um dos métodos mais utilizados na avaliação de pacientes com suspeita de coronariopatia por seu valor diagnóstico e prognóstico. Duas de suas maiores limitações são o uso de radiação e a duração prolongada dosexames. Entretanto, novas Gamacâmaras de CZT (GC-CZT) têm permitido reduzir as doses dos radiotraçadores empregadas e o tempo de aquisição. O valor prognóstico desses novos protocolos não é conhecido.Objetivo: Determinar o valor prognóstico de um novo protocolo de CMP ultrarrápido e de baixa radiação numa GC-CZT. População: Pacientes com suspeita de coronariopatia consecutivamente submetidos a CMP numa GC-CZT no período de novembro de 2011 a junho de 2012.Metodologia: Foi utilizado protocolo de mesmo dia, iniciado pela fase de repouso com dose de 5 mCi e posterior estresse com dose de 15 mCi de Tc-99m sestamibi. Os tempos de aquisição foram de 6 e 3 minutos, respectivamente. Os exames foram classificados como normais ou anormais e escores de perfusão (SSS, SRS e SDS) foram calculados. Pacientes foram acompanhados mediante contato telefônico semestral. Os eventos avaliados foram morte, infarto não fatal e revascularização tardia (> 60 dias após CMP). Foi utilizado método de Coxpara identificar os preditores.Resultados: Setecentos e noventa e dois pacientes foram acompanhados por 21,3 ± 3,7 meses. A idade média foi de 65,2 ± 12,7 anos, sendo 50,3% do sexo masculino e o IMC médio de 26,9 ± 4,7. Hipertensão arterial foi o fator de risco mais frequente (59,5%), seguidode dislipidemia (51,9%) e diabetes (23,3%). Estresse físico foi empregado em 438 (55,3%) pacientes; 618 (78%) CMP foram normais. A dosimetria média dos exames foi 6 mSv e a duração média, de 48 ± 11 minutos. Durante o seguimentos ocorreram 12 óbitos, 4 infartos não fatais...

Myocardial perfusion scintigraphy (MPS) is one of the most used imaging methods for the evaluation of patients for coronary artery disease (CAD) due to its diagnostic and prognostic value. Two of its main limitations are radiation use and scan duration. However, CZT cameras (CZT-C) have allowed tracer dose and scan time reductions. However, the prognostic value of these new protocols is not known. Objective: To determine the prognostic value of a new, ultrafast, low dose protocol in a CZT-C. Population: Patients with suspect CAD undergoing MPS from 11/2011 to 6/2012 were studied. Methods: They had a 1-day Tc-99m sestamibi protocol starting with rest study (5 mCi dose) followed by stress (15 mCi). Acquisition times were 6 and 3 minutes respectively. MPS studied were classified as normal or abnormal and perfusion scores (SSS, SRS and SDS) were calculated. Patients were accompanied by 6-month phone calls. Events were defined as death, nonfatal myocardial infarction and late revascularization (> 60 days after MPS) and analyzed with the Cox method.Results: 792 patients were followed for 21.3 ± 3.7 months. Age was 65.2 ± 12.7 years, 50.3% were male and body mass index was 26.9 ± 4.7. Hypertension was the most frequent risk factor (59.5%), followed by hypercholesterolemia (51.9%) and diabetes (23.3%). Exercise was used in 438 (55.3%); 618 (78%) MPS studies were normal. Mean dosimetry was 6 mSv and mean scan time, 48 ± 11 minutes. During follow-up, there were 12 deaths...

Bacteria inside semiconductors as potential sensor elements: biochip progress.

It was discovered at the beginning of this Century that living bacteria-and specifically the extremophile Pseudomonas syzgii-could be captured inside growing crystals of pure water-corroding semiconductors-specifically germanium-and thereby initiated pursuit of truly functional "biochip-based" biosensors. This observation was first made at the inside ultraviolet-illuminated walls of ultrapure water-flowing semiconductor fabrication facilities (fabs) and has since been, not as perfectly, replicated in simpler flow cell systems for chip manufacture, described here. Recognizing the potential importance of these adducts as optical switches, for example, or probes of metabolic events, the influences of the fabs and their components on the crystal nucleation and growth phenomena now identified are reviewed and discussed with regard to further research needs. For example, optical beams of current photonic circuits can be more easily modulated by integral embedded cells into electrical signals on semiconductors. Such research responds to a recently published Grand Challenge in ceramic science, designing and synthesizing oxide electronics, surfaces, interfaces and nanoscale structures that can be tuned by biological stimuli, to reveal phenomena not otherwise possible with conventional semiconductor electronics. This short review addresses only the fabrication facilities' features at the time of first production of these potential biochips.

Self-integration of nanowires into circuits via guided growth.

The ability to assemble discrete nanowires (NWs) with nanoscale precision on a substrate is the key to their integration into circuits and other functional systems. We demonstrate a bottom-up approach for massively parallel deterministic assembly of discrete NWs based on surface-guided horizontal growth from nanopatterned catalyst. The guided growth and the catalyst nanopattern define the direction and length, and the position of each NW, respectively, both with unprecedented precision and yield, without the need for postgrowth assembly. We used these highly ordered NW arrays for the parallel production of hundreds of independently addressable single-NW field-effect transistors, showing up to 85% yield of working devices. Furthermore, we applied this approach for the integration of 14 discrete NWs into an electronic circuit operating as a three-bit address decoder. These results demonstrate the feasibility of massively parallel "self-integration" of NWs into electronic circuits and functional systems based on guided growth.

Recent progress in n-channel organic thin-film transistors.

Particular attention has been focused on n-channel organic thin-film transistors (OTFTs) during the last few years, and the potentially cost-effective circuitry-based applications in flexible electronics, such as flexible radiofrequency identity tags, smart labels, and simple displays, will benefit from this fast development. This article reviews recent progress in performance and molecular design of n-channel semiconductors in the past five years, and limitations and practicable solutions for n-channel OTFTs are dealt with from the viewpoint of OTFT constitution and geometry, molecular design, and thin-film growth conditions. Strategy methodology is especially highlighted with an aim to investigate basic issues in this field.

Molecules on si: electronics with chemistry.

Basic scientific interest in using a semiconducting electrode in molecule-based electronics arises from the rich electrostatic landscape presented by semiconductor interfaces. Technological interest rests on the promise that combining existing semiconductor (primarily Si) electronics with (mostly organic) molecules will result in a whole that is larger than the sum of its parts. Such a hybrid approach appears presently particularly relevant for sensors and photovoltaics. Semiconductors, especially Si, present an important experimental test-bed for assessing electronic transport behavior of molecules, because they allow varying the critical interface energetics without, to a first approximation, altering the interfacial chemistry. To investigate semiconductor-molecule electronics we need reproducible, high-yield preparations of samples that allow reliable and reproducible data collection. Only in that way can we explore how the molecule/electrode interfaces affect or even dictate charge transport, which may then provide a basis for models with predictive power.To consider these issues and questions we will, in this Progress Report, review junctions based on direct bonding of molecules to oxide-free Si.describe the possible charge transport mechanisms across such interfaces and evaluate in how far they can be quantified.investigate to what extent imperfections in the monolayer are important for transport across the monolayer.revisit the concept of energy levels in such hybrid systems.

Novel semiconductor materials for the development of chemical sensors and biosensors: a review.

The aim of this manuscript is to provide a condensed overview of the contribution of certain relatively new semiconductor substrates in the development of chemical and biochemical field effect transistors. The silicon era is initially reviewed providing the background onto which the deployment of the new semiconductor materials for the development of bio-chem-FETs is based on. Subsequently emphasis is given to the selective interaction of novel semiconductor surfaces, including doped conductive diamond, gallium nitride, and indium nitride, with the analyte, and how this interaction can be properly transduced using semiconductor technology. The main advantages and drawbacks of these materials, as well as their future prospects for their applications in the sensor area are also described.

Nanoelectronics from the bottom up.

Electronics obtained through the bottom-up approach of molecular-level control of material composition and structure may lead to devices and fabrication strategies not possible with top-down methods. This review presents a brief summary of bottom-up and hybrid bottom-up/top-down strategies for nanoelectronics with an emphasis on memories based on the crossbar motif. First, we will discuss representative electromechanical and resistance-change memory devices based on carbon nanotube and core-shell nanowire structures, respectively. These device structures show robust switching, promising performance metrics and the potential for terabit-scale density. Second, we will review architectures being developed for circuit-level integration, hybrid crossbar/CMOS circuits and array-based systems, including experimental demonstrations of key concepts such lithography-independent, chemically coded stochastic demultipluxers. Finally, bottom-up fabrication approaches, including the opportunity for assembly of three-dimensional, vertically integrated multifunctional circuits, will be critically discussed.