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Objective: Nowadays, simulation of clinical environment in medical education system (simulation-based learning) has led to a huge revolution in the quality of education and has increased the safety of educators and patients. In this study, we investigated the effect of teacher-made neck and lung simulators in teaching cricothyrotomy skills for emergency medicine residents. Methods: In this pre-post test study, all faculty member of emergency medicine of Tabriz University of medical sciences specialty were invited to participate. After holding an educational and training session for assistants on a teacher-made moulage, all emergency medicine residents performed a tracheostomy on the commercial moulages of the skill lab unit for the second time and their scores were recorded. Results: In this study, 23 emergency medicine residents participated. The mean±standard deviation of age was 35.91±3.57 years. There was a significant difference between the mean duration of cricothyrotomy before and after the training (P value=0.006). There was also a significant difference between the mean scores obtained by residents in the pre-and post-training evaluation (P value

Non-contact, cost-efficient, and long-range precision metrology is essential for applications in diverse areas, from 3D sensing and robotics to automated manufacturing, and multiwavelength interferometry is a compelling candidate. Here, we present a new arithmetic approach for multiwavelength phase unwrapping, with the maximum theoretical range and tolerance to measurement noise in phase. We supplement our formulation with a simultaneous phase shifting interferometry setup with a low measured standard deviation of phase, $\sigma _\phi ={2\pi }/{1325}$ . We unwrap the interferometric phases of experiments performed through wavelengths with a greatest common divisor of 25 nm, demonstrate a range equal to their lowest-common-multiple with the precision of a single wavelength interferometer, and reconstruct three-dimensional scenes based on a single-pixel 3D imaging system.

Background and Objectives: Tea is considered one of the most consumed drinks around the world and the health benefits of it have recently attracted the attention of different researchers. It has also been proven beneficial in preventing the danger of some diseases like cancer and cardiovascular problems. Further, lipid oxidation is one of the major problems in food products. Considering the above-mentioned issues, the present review focused on various techniques used to extract polyphenols from different kinds of tea, as well as their use in the food industry. Results and Conclusion: Based on our findings in this review, the main components of tea are polyphenols that have health benefits and include catechins, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, gallic acid, flavonoids, flavonols, and theophlavins. From these components, catechin is regarded as the most beneficial component. Many techniques have been discovered and reformed to extract tea compounds such as solvent-based extraction, microwave-assisted water extraction, and ultrasound-assisted extraction techniques. Overall, the microwave-assisted water extraction method is a useful method for extracting tea polyphenols, which may be used in the meat, oil, and dairy industries.

In this study, a bacterial detection technique utilizing benefits of both positive and negative dielectrophoresis has been simulated with COMSOL Multiphysics. The two dimensional proposed model has six microelectrodes across microfluidic channel. Four of them were positioned on the upper side and the rest were positioned on the bottom side of the microchannel, which serve as a bacteria concentrator using negative dielectrophoresis and as a bacteria detector using positive dielectrophoresis, respectively. In this simulation, the target particle is Escherichia coli that was flowing into the microchannel and repelled under negative dielectrophoretic force exerted by the upper side microelectrodes, and were pushed toward the bottom side microelectrodes situated at the downstream. Finally, concentrated bacteria have been captured and detected by dielectrophoretic impedance measurement method. The numerical simulation proved that negative dielectrophoretic force could increase sensitivity with respect to the absence of the negative dielectrophoretic force and eventually, results represented that 80 percent of releasing E. coli bacteria trapped near bottom side microelectrodes.

We present a detailed study on the n-channel single-gate junctionless transistor (JLT) at the $${10}-\hbox{nm}$$ node. We investigate the influence of its structural parameters on the on-state current and the off-state leakage current. Furthermore, we show that the use of high-k spacers may not be advantageous in future nanoscale junctionless transistors and confirm this argument by simulation. We also present the results of our investigation on process variations, including the sensitivity of the JLT to random dopant fluctuations as well as the gate work function using Monte Carlo simulations. These results are then compared with those of a conventional FinFET. Finally, we provide design guidelines for JLTs at $${10}-\hbox{nm}$$ gate length.

This paper aims to study the mechanical behavior of rocks using the cohesive crack model (CCM) and grain-based model (GBM) within the distinct element method (DEM) simulations. In the GBM-DEM, the Voronoi tessellation scheme is used and the intact material is simulated as assemblies of a number of particles bonded together at their contact areas. Implemented CCM defines the nonlinear behavior of the grain interfaces under various modes of loading. Numerical simulation of a tension–compression and direct shear tests is conducted to verify the correct implementation of CCM. Moreover, in the application of such a numerical framework, the uniaxial and biaxial compression tests as well as the Brazilian disc test are simulated in the universal distinct element code using a calibration process and then the results are compared with the relevant responses of the rock sample. Finally, the capability of soft computing method, i.e., artificial neural network (ANN) for predicting macromechanical parameters of rock, i.e., UCS based on input cohesive contact shear strength parameters, i.e., cohesion and friction angle, is explored. Results indicate that the ANN model can be quite accurate predictor of uniaxial compressive strength (UCS) and therefore used as a potential tool to aid in estimating target values.

Increasing the interest in the silicon-based devices resulted in developing new methods and techniques to achieve advanced and more reliable designs and devices. In this study, we have developed a combination method of photolithography and electron-beam lithography (EBL) in order to maximize the efficiency and reducing time and costs. Nanometric and micrometric patterns were created using EBL and photolithography methods, respectively. In order to prove the sensing applications, the EBL-based fabricated electrodes were successfully designed and tested as a hydrogen peroxide (H2O2) biosensor using horseradish peroxidase (HRP) enzyme on a graphene oxide substrate. Photoresist provided a passive layer which reduced the passivation steps in the fabrication. The interdigitated electrodes were used to maximize the connections with the graphene oxide substrate. The result was an ohmic biosensor that exhibits a linear relationship with the logarithm of H2O2 concentration in the range between 0.1 µM and 100 mM. The limit of detection (LOD) was about 51 nM.

In this paper, fabrication of nanostructures of conducting polypyrrole (PPy) thin films on the surfaces by in situ chemical polymerization in the presence of different anionic dopants including anthraquinone-2-sulfonic acid sodium salt monohydrate/5-sulfosalicylic acid dehydrate (AQSANa/SSCA) and camphor sulfonic acid (CSA) is reported. “Lift-off process” combined with electron beam lithography (EBL) is used for fabrication of nano patterns of conducting PPy thin films down to 100 nm. In addition, the ability to create ordered single PPy nanowires of controlled dimension, with very high aspect ratio, and dendrite free features between Au electrodes for fabricating of field effect transistor (FET) was demonstrated by single wires of PPy-CSA and PPy-(AQSANa,SSCA) with 250 nm widths, up to 12 μm lengths and 100 nm thickness. I–V measurements of both single PPy-CSA (˜ 124 S/cm) and PPy-(AQSANa,SSCA) (˜ 5 S/cm) nanowires indicated Ohmic or space charge limited conduction, depending on the applied bias on the contact electrodes. A considerable modulation in the electrical conductivity of PPy-CSA and PPy-(AQSANa,SSCA) nanowire p-FETs was demonstrated as a result of varying the gate potential. Both PPy-CSA and PPy-(AQSANa,SSCA) nanowire p-FETs provide good performance transistors, nevertheless show different device electrical characteristics due to used different anionic dopants.

By adding two disks to a standard silicon micro-ring resonator, a very high-quality factor (Q) asymmetric resonance with Q values as high as 7.773 × 105 and slope rates in excess of 880 dB/nm can be achieved. A circuit model has been proposed for this device based on which an analysis has been carried out that can predict the effect of reflections in the coupling components. Depending on the coupling coefficient between the disks and the micro-ring resonator (MRR), it is possible to use this design in three regimes, with different spectral features. Moreover, it is shown that the disks introduce a discontinuity in the transmission spectrum and the relative positioning of the disks in the ring provides a new degree of freedom in the design step. The proposed device features a high extinction ratio (ER) around 1550 nm and could be fabricated in any standard silicon photonics technology without requiring any extra materials or processing steps. The proposed resonator has a high sensitivity of Δλ Res (nm)/Δn > 299 nm/RIU, which makes it suitable for sensing applications and efficient modulators.

Background: Serum levels of MMP-2 and MMP-9 were evaluated in 26 dogs with mammary tumors before surgical treatment and then 1, 4 and 12 months after surgery by gelatin zymography. Serum samples from 26 dogs with the normal condition were used as the control in the zymographic evaluation. In addition, pathology evaluation was performed in patients. Results: Our results showed that lymph node metastases are risk factor for death and metastasis and or recurrence (M/R) in canine malignant mammary tumors. Dogs with benign and malignant mammary tumors showed bands of Pro-MMP-2, Pro-MMP-9 and active MMP-9 with molecular weights of 72, 92 and 82, respectively. However, only Pro-MMP-2 and Pro-MMP-9 bands appeared in the serum of control group and two patients with benign lobular hyperplasia tumor. Our results showed that Pro-MMP-2 levels increased more dramatically (2 fold) in malignant tumors than in benign tumors and control groups. Also, in patients with M/R, there was a significant increase in the levels of Pro-MMP-9 in serum samples 12 months after surgery compared with other sampling times. Meanwhile, the presence of active MMP-9 (especially in samples 4 and 12 months after surgery of malignant tumors), regardless of its amount, is important in terms of prognosis for recurrence or metastasis. Also, active MMP-2 was only detected in some malignant and metastatic tumors. Observation of active MMP-2 band is very important for M/R than active MMP-9 because its presence regardless of values coincides with a definite M/R, unlike the active form of MMP-9. Necrosis, stromal invasion, and infiltrative growth increase risk of the development of M/R and the presence of necrosis is a risk factor for death. Conclusions: In conclusion, serum zymograhpy may be used at regular intervals after surgery to check for the possibility of M/R in dogs with mammary tumors.More research is needed in this regard.

Cardiovascular diseases (CVDs) are considered as the main reason of mortality around the world. Echocardiography is the most common imaging modality for diagnosis or treatment follow-up of CVDs. However, because of speckle-noise corruption and low resolution, segmentation of heart chambers in echo-images is a challenging endeavor. We previously proposed a probabilistic atlas as a prior model for the heart chambers in echo-images. In this paper, we propose a new active contour for the segmentation of cardiac chambers by using that digital atlas. Our deformable model effectively combines the global and local (patch-based) region-based energy functionals. Also, to extract all the cardiac chambers, we determine four active contours in every echo-image (one contour for each chamber in the four-chamber view). For simultaneously evolving all the curves, a coupling term is also added to the energy functional. Finally, the evolution equation of each active contour is computed through the Euler-Lagrange equation. Experimental results demonstrate that our method provides accurate solutions compared to expert delineations.

A simple model is designed for an inductive immunosensor in which the magnetic particles are attached to the bioreceptors to form a sandwich on the surface of an inductor. The inductor consists of a coil covered on a silicon oxide wafer. The coil comprises 250 turns of a planar gold wire, which is approximately 200 nm thick and 392 mm long, placed in a circle with a diameter of 2 mm. The model is well characterised by controlling the geometrical and electrical parameters and also the permeability of the magnetic material. To evaluate the feasibility of the model for virus monitoring, a novel inductive immunosensor is designed and for the first time applied for the detection of hepatitis B surface antigen (HBsAg). At first, Fab′ segment of primary anti-HBsAg is immobilised on the coil. Then, the coil is exposed to HBsAg and the complex is introduced to a secondary antibody conjugated with magnetic particles to form an immune-sandwich. Finally, the influence of magnetic particles on the coil inductance is recorded and used as a signal for HBsAg detection. The magnetic inductive immunosensor showed specific responses toward HBsAg with the detection limit of 1 ng mL−1, linear range of 1 to 200 ng mL−1, and a sensitivity of 6 × 10−4 mL ng−1. The experimental results showed a very good agreement with simulation data indicating the compatibility of sensor sensitivity to the expected theoretical values.

Summary Background & aims The present systematic review and meta-analysis were conducted to investigate the effects of capsinoids and fermented red pepper paste (FRPP) supplementation on Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP). Methods Relevant studies, published up to May 2020, were searched through PubMed/Medline, Scopus, ISI Web of Science, Embase, and Google Scholar. All randomized clinical trials investigating the effect of capsinoids and FRPP supplementation on blood pressure including SBP and DBP were included. Results Out of 335 citations, 7 trials that enrolled 363 subjects were included. Capsinoids and FRPP resulted in significant reduction in DBP (Weighted mean differences (WMD): −1.90 mmHg; 95% CI, −3.72 to −0.09, P = 0.04) but no significant change in SBP (WMD: 0.55 mmHg, 95% CI: −1.45, 2.55, P = 0.588). FRPP had a significant reduction in SBP. Greater effects on SBP were detected in trials, lasted ≥12 weeks, and sample size >50. Capsinoids with dosage ≤200 and FRPP with dosage of 11.9 g significantly decreased DBP. Conclusion Overall, these data suggest that supplementation with FRPP may play a role in improving SBP and DBP but for capsinoids no effects detected in this analysis on SBP and DBP.

The theories of occupational therapy always emphasize on the relationship between a person, his or her context, and occupations or tasks. Based on these theories, proper occupational performance results from appropriate interaction between these components. There is little evidence on the clinical practice of this theory in cardiac rehabilitation. So, this study aimed to investigate the implication of the Ecology of Human Performance (EHP) in a 50 years old man with cardiovascular disease. The participant was assessed and treated at home by an occupational therapist based on EHP principles. Results indicated that the intervention based on EHP was associated with improved performance and satisfaction of performance as well as independence in the activities of daily living. So, occupational therapists can use EHP to provide client-centered interventions and improve the occupational performance of clients with cardiovascular diseases. However, further studies with more methodological rigor are needed on this topic.

With regard to the importance of the manufacturing, industrial sector for economic growth and its priority for motivating other sectors to development, the paper is aimed to study the structural changes condition in the Indian manufacturing industries. The changing in value-added of industrial activities due to industrial and economic policies is an important indicator for the recognition of manufacturing industries structure. We have analyzed the industrial structure and competitiveness of each industrial activity by using data value-added of manufacturing industries and common indexes such as the structural changes index in the period of 1980-2013. The results of structural index analysis showed that of textile products; leather; basic chemicals and chemical products in the periods of 1980-98 and also in the periods after 2000industries wearing apparel; dressing and dyeing of fur tanning and dressing of leather ; wood and products of wood; motor vehicles, trailers and semi-trailers; recycling; other transport equipment have been the industrial activities that their structural changes indexes has been positive and they have had the highest competitiveness in comparison to other industrial activities and the greatest opportunities to create value-added.

Occupation-based models can integrate the occupation into Occupational Therapy (OT) practice. These models offer a theoretical basis for OT interventions. Person-Environment-Occupation (PEO) is one of these models, but there is limited evidence to outline the use of PEO to support OT in cardiovascular diseases. Therefore; the aim of this study is to investigate the usefulness of this model in a patient with a cardiovascular disease. The participant was a 48-year old woman with cardiac disease (heart failure with NHYA 3). Results indicate that the application of PEO model significantly improved physical function and the quality of life. The findings of this study suggest that PEO can guide OT practice in cardiac rehabilitation.

There is limited information about intrascrotal hemangioma tumors and their gelatinase activity in the dogs. This study was planned to identify the serum gelatinases in male dogs affected by intrascrotal hemangioma and determine their prognostic value in tumor recurrence. Ten dogs with intrascrotal hemangioma were diagnosed among a total of 65 testicular excision samples. According to the incidence of recurrence, the patients divided into two groups: tumors with recurrence and tumors with no-recurrence. Serum gelatinase activity was assayed by semi-quantitative zymography to determinate their prognostic value in canine intrascrotal hemangioma. Both latent and active MMP-9 and only latent MMP-2 appeared in the gels. Gelatinases showed a significant higher serum activity in dogs with hemangioma than those of the normal dogs. There was a significant association between increased serum activity of gelatinase A and gelatinase B and tumor recurrence. The dogs with hemangioma had a shorter disease-free survival time; however, multivariate analysis showed that serum activity of MMP-2 and MMP-9 was not an independent prognostic factor. According to the findings, MMP-2 and MMP-9 may cause a progressive angiogenesis in canine intrascrotal hemangioma and tumor recurrence subsequently. Our results showed that serum activity of MMP-2 and MMP-9 may be used as a non-invasive prognostic marker for tumor recurrence prediction in dogs affected by intrascrotal hemangioma.

Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae), a common zoophytophagus bug, is a biological control agent for several groups of noxious agricultural pests, including whiteflies, aphids, and leafminers. To improve mass-rearing of this species and to optimize its application in integrated pest management, nymphal survival and developmental times of this predator were examined at seven constant temperatures ranging from 14 through 34°C. Eggs developed to adulthood at all temperatures tested. Egg-adult developmental time decreased sharply with increasing temperature, except at 34°C (17.21 d), for which developmental time was significantly longer than that obtained at 31°C (15.59 d). The lowest (11.36%) and highest (28.26%) percentage of mortality was found at 28 and 14°C, respectively. To describe the development rate of immature stages of N. tenuis as a function of temperature, two linear and 26 nonlinear models were fitted. The lower temperature threshold (T0) and thermal constant (K) of total immature stages were estimated by the ordinary (10.94°C and 318.37 DD) and Ikemoto (10.28°C and 339.57 DD) linear models. Based on the Akaike information criterion (AIC), Lactin-1, Analytis-1/Allahyari and Janisch/Kontodimas were the best models to describe the temperature-dependent development rate of egg, nymph and whole immature stages of the predator, respectively. Our findings provide information on N. tenuis biology that will improve application of this predator as a biological control agent.

A back-gated multilayer nanoribbon molybdenum disulfide (MoS2) transistor grown by chemical vapor transport and doped using polyethylene oxide cesium perchlorate is fabricated and characterized. Ions in the polymer dielectric are directed by side gates to the source and drain access regions where they form electric double layers (EDLs) that control the carrier densities. This allows the junctions of the same transistor channel to be reconfigured as an n-MOSFET, p-MOSFET, and as a tunnel field-effect transistors. The EDLs are formed at room temperature and then locked into place by cooling the polymer below the glass transition temperature (~240 K). Transport measurements are presented and explained using simulated band diagrams. Both n and p-conduction in MoS2 is demonstrated using solid polymer ion doping, enabling characterization of a semiconductor in which the doping of the same channel has been reconfigured to form three different transistor configurations.

Among environmental factors, temperature has a direct and crucial influence on the key life processes of survival, development, reproduction, and movement of poikilothermic animals and hence their population dynamics. The lower and upper temperature thresholds and optimal temperature have ramifications for all major life processes, where within a specific range, a temperature change results in a proportional rise or fall of the rate of any given process. There are some basic approaches for modeling development response to temperature in arthropods. The oldest and most widely used model is a simple linear description of arthropod development in relation to temperature. The linear model forms the basis of the well-known thermal summation or degree-day (DD) approach to timing prediction. The second approach for predicting arthropod development rate is nonlinear mathematical models. However, given the fundamental role of thermal models in forecasting and integrated pest management programs, the main purpose of this paper was to facilitate the use of thermal models to estimate the developmental response of arthropods to temperature and select the appropriate model with a view to goodness-of-fit and generalizability by designing a user-friendly software. In this paper, the linear and most common nonlinear thermal models and the main criteria for selecting appropriate models are also reviewed.

Surface enhanced Raman scattering (SERS) systems with large number of active sites exhibit superior capability in detection of low concentration analytes. In this paper, we present theoretical as well as experimental studies on the optical properties of a unique hybrid nanostructure, Ag NPs decorated silicon double nanocones (Si-DNCs) array, which provide high density of hot spots. The Si-DNC array is fabricated by employing electron beam lithography together with plasma etching process. Multipole analysis of the scattering spectra, based on the multipole expansion theory, confirms that the toroidal dipole moment dominates over other electric and magnetic multipole moments in the Si-DNCs array. This response occurs as a result of generating current densities flowing in opposite directions and consequently generating H-field vortexes inside the nanocones. Moreover, SERS applicability of this type of nanostructure is examined. For this purpose, the Si-DNCs array is decorated with Ag nanoparticles (NPs) by means of electroless deposition method. Simulation results indicate that combination of multiple resonances, including LSPR resonance of Ag NPs, longitudinal standing wave resonance of Ag layer and inter-particle interaction in the gap region, result in a significant SERS enhancement. Our experimental results demonstrate that Si-DNC/Ag NPs array substrate provides excellent reproducibility and ultrahigh sensitivity.

More than 40% of energy consumption in Iran associated with the building sector. Among the factors affecting energy consumption, time lag and decrement factor of the walls can be mentioned, which usually are not considered in the design of building of Iran. Therefore, in the present study, time lags and decrement factor for different building materials that prevalently are utilized in Iran have been investigated. In this research, the transient heat conduction equation is solved analytically using Green function under time-dependent convection boundary conditions. The effect of different parameters such as wall thickness and both inner and outer heat transfer coefficients as well as the effect of the thermal insulation layer in sandwich wall on time lag and decrement factor is investigated. The results indicate that the thickness and the type of the building material have a significant effect on the time lag and decrement factor of the wall. Also, it is shown that inside combined convection and radiation heat transfer coefficients affects time lag and decrement factor of the walls. The results of the present study are applicable for designing more effective passive solar buildings in Iran and optimal design of walls and other related areas resulting in energy saving.

Prediction of the rate of penetration (ROP) is an important task in drilling economical assessments of mining and construction projects. In this paper, the predictability of the ROP for percussive drills was investigated using the artificial neural networks (ANNs) and the linear multivariate regression analysis. The “power pack” frequency, the revolution per minute (RPM), the feed pressure, the hammer frequency, and the impact energy were considered as input parameters. The results indicate that the ANN with the regression model predicts the ROP under different conditions with high accuracy. It also demonstrates that the ANN approach is a beneficial tool that can reduce cost, time and enhance structure reliability. publishedVersion

In this paper, we report on growth of ZnO nanorods on the surface of gold interdigital electrodes and its implementation as a conductive n-type channel for the fabrication of a liquid-gated field effect transistor. Glucose oxidase was immobilized on the surface of the ZnO nanorods and the fabricated device was used as a four-electrode glucose biosensor. The resistance of the conductive channel was affected by addition of glucose. The applied bias voltage to the gate in the fabricated device affects the channel resistance in the same manner as the increase of enzymatic products during the glucose oxidation. Large effective area, good conductivity, and biocompatibility properties of ZnO nanorods are the key features in this highly sensitive and stable biosensor. Our measurements showed that the threshold voltage of transistor was about 0.75 V. The current increased in the presence of the glucose and exhibited a dynamic linear range with the logarithm of glucose concentration in the range between 0.01 and 5 mM. The detection limit was about 3.8 μM.

Tunneling field-effect transistors (TFETs) are gaining attention because of their good scalability and low leakage current. However, they suffer from low on-state current and severe ambipolar conductivity. To address these issues, in this paper, we have proposed a novel junctionless nanowire TFET with induced source side tunneling realized by a hetero-gate-dielectric (HGD JN-TFET). This approach induces a local dip in the conduction band edge at the tunneling junction leading to an abrupt transition between the on and off-states as well as subthreshold swing (SS) as low as 45 mV/dec at low drain voltages. The proposed structure provides Ion of 8.7×10−6 A/µm and Ioff of 1.1×10−11 A/µm. Also, we have shown that the length of high-k gate insulator as well as its dielectric constant can significantly affect the performance and power efficiency of this device.

High contact resistance is one of the primary concerns for electronic device applications of two-dimensional (2D) layered semiconductors. Here, we explore the enhanced carrier transport through metal-semiconductor interfaces in WS2 field effect transistors (FETs) by introducing a typical transition metal, Cu, with two different doping strategies: (i) a "generalized" Cu doping by using randomly distributed Cu atoms along the channel and (ii) a "localized" Cu doping by adapting an ultrathin Cu layer at the metal-semiconductor interface. Compared to the pristine WS2 FETs, both the generalized Cu atomic dopant and localized Cu contact decoration can provide a Schottky-to-Ohmic contact transition owing to the reduced contact resistances by 1 - 3 orders of magnitude, and consequently elevate electron mobilities by 5 - 7 times higher. Our work demonstrates that the introduction of transition metal can be an efficient and reliable technique to enhance the carrier transport and device performance in 2D TMD FETs., Under review

In this article, an analytical predictive model of the negative capacitance (NC) effect in symmetric long channel double-gate junctionless transistor is proposed based on a charge-based model. In particular, we have investigated the effect of the thickness of the ferroelectric on the I-V characteristics. Importantly, our model predicts that the negative capacitance minimizes short channel effects and enhances current overdrive, enabling both low power operation and more efficient transistor size scaling, while the effect on reducing subthreshold slope shows systematic improvement, with subthermionic subthreshold slope values at high current levels. Our predictive results in a long channel junctionless with NC show an improvement in ON current by a factor of 6 in comparison to junctionless FET. The set of equations can be used as a basis to explore how such a technology booster and its scaling will impact the main figures of merit of the device in terms of power performances and gives a clear understanding of the device physics. The validity of the analytical model is confirmed by extensive comparisons with numerical TCAD simulations in all regions of operation, from deep depletion to accumulation and from linear to saturation.

Peer-to-peer network is organized on top of another network as an overlay network. Super peer network is one of the peer-to-peer networks. A super peer, in a super peer based network, is a peer that has more responsibility than other peers have and is responsible for some of the tasks of network management. Since different peers vary in terms of capabilities, selecting a super peer is a challenge in super peer based networks. Gradient topology is of the networks based on super peers. Existing adaptive algorithms, which have been proposed to select super peer in gradient topology, are not aware of delays among the peers. In this paper, the proposed algorithm being aware of the delay among super peers, using learning automata, which is a reinforcement model of learning, selects the new super peers in an adaptive manner. According to the simulation results, the proposed algorithm with respect to the average end-to-end delay in community of super peers, and error in the super peer selection, has better performance than existing algorithms.

We present the signal-to-noise performance of a short-wave infrared detector, which offers an internal avalanche-free gain. The detector is based on a similar mechanism as the heterojunction phototransistor and takes advantage of a type-II band alignment. Current devices demonstrate a noise-equivalent sensitivity of ~670 photons at 260 K and over a linear dynamic range of 20 dB. While this level of sensitivity is about an order of magnitude better than an ideal p-i-n detector attached to the same low-noise amplifier, it was still limited by the amplifier noise (~2600 electrons root mean square) due to the insufficient device gain. Performance comparison with other SWIR detector technologies demonstrates that the so-called electron-injection detectors offer more than three orders of magnitude better noise-equivalent sensitivity compared with state-of-the-art phototransistors operating at similar temperature.

BACKGROUND It has been shown that pollen as a dietary supplement may increase the establishment of generalist predatory mites, and therefore pest control by these mites can be provided. Life table studies were performed to evaluate the nutritional value of seven different pollens (almond, castor-bean, date-palm, maize, bitter-orange, sunflower and mixed bee pollen) as a supplementary food source for the spider mite predator Neoseiulus californicus McGregor. In addition, the nutritional quality of each pollen species was assessed through morphological and chemical analysis. RESULTS Preadult duration was longer when the predator fed on castor-bean pollen (10.01 days) and bee pollen (9.94 days) compared with the others (5.58-7.27 days). The cohort reared on almond pollen had the highest intrinsic rate of increase (r) (0.231 day-1 ), and those on mixed bee pollen had the lowest r (0.005 day-1 ). The levels of nutritional content (sugar, lipid and protein) were significantly different among tested pollens. CONCLUSIONS Comparison of N. californicus life table parameters on different diets revealed that the almond pollen (and after that the maize pollen) was a more suitable diet than the others. These findings will be useful in developing appropriate strategies for conservation of N. californicus to control spider mites. © 2016 Society of Chemical Industry.

Realization of high-aspect-ratio vertical features on silicon substrates is a crucial step in the fabrication process of microelectromechanical systems devices. Therefore deep reactive ion etching (DRIE) plays an important role in the fabrication of those structures. Recently many efforts have been made in order to propose the novel DRIE processes in order to achieve higher aspect ratios; however, they suffer from complexity and high sensitivity to process parameters. Herein, the authors report a high-aspect-ratio vertical etching of silicon by employment of proposed low temperature SiO2 deposition on Si substrate, using of H2 and O2 gases. The process employs multiple sequences of alternating steps of etching by a fluorine donating gas such as SF6 and sidewall passivation by SiO2. Etch rates reach up to 0.8 μm min−1 and values of aspect ratio higher than 100 are readily achievable by this process. Furthermore, this process also allows for controlled fabrication of nano-wall and high-aspect-ratio nano-wall tube as well as three-dimensional silicon structures.

In this article, an analytical predictive model of interface charge traps in symmetric, long-channel double-gate, junctionless transistors (JLTs) is proposed based on a charge-based model. Interface charge traps arising from exposure to chemicals, high-energy ionizing radiation, or aging mechanism could degrade the charge-voltage characteristics. The model is predictive in a range of temperatures from 77 to 400 K. The validity of the approach is confirmed by extensive comparisons with numerical technology computer-aided design (TCAD) simulations in all regions of operation from deep depletion to accumulation and from linear to saturation.

Metal-semiconductor (MS) contacts were changed from Schottky to Ohmic in synthesized tungsten disulfide (WS 2 ), due to Cu doping during the synthesis. Significant reductions of contact barrier and resistance were achieved. A statistical study shows transistor performance including carrier mobilities, on/off ratios, on-current densities, and subthreshold swings were also improved significantly with Cu doping.

In this paper we report on the design of an integrated waveguide photodetector designed for use in an integrated optical gyroscope with high responsivity and wide bandwidth. The butt and evanescent coupling are two common schemes for the coupling between the waveguide and the photodetector. The butt and evanescent coupling are compared, and a process flow for fabrication of such device is described. At a reverse voltage bias of −1 V, a responsivity higher than 0.6 A/W and 0.5 A/W were obtained for the butt and evanescent coupling respectively, the 3dB cut-off frequency and dark current were 55 GHz and 10 nA for both schemes.

Cabbage aphid, Brevicoryne brassicae (L.), is a serious pest on canola, Brassica napus L. Estimation of required degree-days for 50% emergence of the population is of special interest for controlling this aphid. To precisely predict 50% emergence of aphid populations as a function of accumulated degree-days, eight distribution models were tested. Models were evaluated statistically and validated with a separate data set collected from three canola fields. Observed cumulative emergence of the aphid was well described by three models. The sigmoid model proposed by Brown and Mayer was recommended to describe 50% emergence of the cabbage aphid population, because the model is simple and the parameter b denotes the accumulated degree-days at 50% emergence. The selected model could be used to better time insecticide applications and to more efficiently forecast aphids in canola fields.

Laser refrigeration of solids has emerged as a viable solution for vibration-free and compact cooling that does not require any moving parts or cryogenic liquid. So far, rare-earth doped glasses are the only bulk materials that have provided efficient laser cooling based on the anti-Stokes process. These materials have low indices of refraction and are suitable for efficient luminescence extraction. However, up until this date, laser cooling of bulk semiconductors has not been achieved. One major challenge that needs to be addressed is the photoluminescence trapping and the consequent photon recycling. In this paper, we explain various methods to enhance light extraction for the purpose of laser cooling. We specifically provide guidelines for design and fabrication of graded index and subwavelength structures to maximize the extraction efficiency. Furthermore we present novel techniques for increasing the external quantum efficiency and enhancing the overall laser cooling efficiency.

In this paper we propose a novel RF LDMOS structure which employs a thin strained silicon layer at the top of both the channel and the N-Drift region. The strain is induced by a relaxed Si"0"."8Ge"0"."2 layer which sits on top of a compositionally graded SiGe buffer. We have used a 2D device simulator to investigate improvements in the output characteristics of the device including saturation and linear transconductance, current drivability, cut off frequency and the on resistance. Furthermore we have examined the capacitance voltage behavior of the proposed strained silicon LDMOS device and have compared it with that of the conventional LDMOS device. It is observed that the gate capacitance increases in strong inversion with strain, but remains relatively unaffected in depletion and accumulation modes of the device operation.

A new ranging technique is proposed using multi-wavelength laser interferometry with wavelength de-multiplexed detectors to alleviate the range-resolution trade-off inherent in many contemporary ranging techniques. We demonstrate 3-mm range and 10-nm resolution with two-wavelengths.

The optical properties of 1-D superlattices formed by armchair graphene nanoribbons embedded in hexagonal boron nitride superlattices (BNSLs) are studied. A set of tight-binding (TB) parameters is proposed, which gives results in excellent agreement with first-principle calculations. Based on the tight-binding model, it is demonstrated that in BNSLs, a larger bandgap opening is achieved than in hydrogen-passivated superlattices (HSL). The optical properties of BNSL and HSL are studied by employing the nonequilibrium Green function method and are verified with first-principle calculations. The role of line-edge roughness on the optical properties of such devices is carefully investigated.

Electrical performance of highly scaled III-nitride Ga-face and N-face HEMTs have been investigated using a two-dimensional numerical simulator. Four HEMT structures were studied, in three of which GaN substrate were grown in Ga-polar direction and in the last structure GaN substrate was grown in N-polar direction. Simulation results indicate that N-face structure has superior performance as compared with Ga-face structures. The undesirable effects originated from a potential distribution in the channel and current injection through the buffer effectively decrease and therefore their resultant effects such as low output conductance, threshold voltage shift and soft pinch-off become much less noticeable in N-face HEMT structure as compared with Ga-face HEMTs with similar geometry. Furthermore, superior small signal, high frequency characteristics as compared to Ga-face HEMTs structures can be achieved.

This article reintroduces power gating technique in different hierarchical levels of static random-access memory (SRAM) design including cell, row, bank and entire cache memory in 16 nm Fin field effect transistor. Different structures of SRAM cells such as 6T, 8T, 9T and 10T are used in design of 2MB cache memory. The power reduction of the entire cache memory employing cell-level optimisation is 99.7% with the expense of area and other stability overheads. The power saving of the cell-level optimisation is 3× (1.2×) higher than power gating in cache (bank) level due to its superior selectivity. The access delay times are allowed to increase by 4% in the same energy delay product to achieve the best power reduction for each supply voltages and optimisation levels. The results show the row-level power gating is the best for optimising the power of the entire cache with lowest drawbacks. Comparisons of cells show that the cells whose bodies have higher power consumption are the best candidates for power ga...

In the past two decades 3-D cameras have proven to be one of the next revolutions in machine vision. However, these devices are still an emerging technology with a particularly narrow set of commercially available devices. In this paper, the concept and execution of the first short wavelength infrared (SWIR) time-of-flight (ToF) 3-D camera system operating at a wavelength of 1550 nm is presented. By decoupling the optical and electrical components of the system in an open architecture we not only surpass many of the limitations of an on-chip integrated solution, but also can easily change the imaging device based on the requirements of the application. We achieve modulation frequencies up to 150 MHz, which exceeds the conventional values currently published for other large format modulators by about five times. This increase in the modulation frequency allows for a TOF camera with significantly higher depth resolution, while the open architecture design allows for a highly reconfigurable device that can be modified for specific working conditions.

While planar two-dimensional field effect transistors (FETs) are being widely explored [1], there are only a few reports of MoS2 [2-4] and WS 2 [5-8] nanotube (NT) and nanoribbon (NR) FETs. A benefit of these crystalline forms is the absence of edges associated with traps, and the potential for ideal subthreshold swing with wrapped gates. Density functional theory predicts that the bandgap of MoS 2 nanotubes remains direct and decreases with diameter [9] due to strain. This makes nanotubes appealing for tunnel FETs at the scaling limit because the decrease in bandgap should provide an increase in current. Here we report the first WS2 NT and NR FETs synthesized by chemical vapor transport (CVT) [10]. Prior reports on WS 2 [5-8] are based on sulphurization of W and WO nanowhiskers.

Optical modulators are integral parts of optical communication systems. They are in charge of modulating data in an optical network. Therefore, design, modeling, simulation and fabrication of optical modulators have been in the focus of interest to many researchers. In this article we intend to report our results on the modeling and simulation of a MOS optical modulator based on the SOI waveguide technology. Our numerical studies predict that the scaling of the gate oxide thickness and its permittivity are key parameters to control the properties of the waveguide channel and so the performance of the optical modulator. Our results indicate that insulator's dielectric constant is the dominant parameter to promote the refractive index change. When low-K materials such as vacuum or SiO 2 are employed as gate oxide, scaling is not very advantageous, while if a high-K gate oxide such as TiO 2 is used scaling of the oxide thickness can play an important role in the performance of the modulator. The refractive index changed in the order of 10−3 by the use of TiO 2 .

Optical coherence tomography (OCT) has been utilized in a rapidly growing number of clinical and scientific applications. In particular, swept source OCT (SS-OCT) has attracted many attentions due to its excellent performance. So far however, the limitations of existing photon detectors have prevented achieving shot-noise-limited sensitivity without using balanced-detection scheme in SS-OCT, even when superconducting single-photon detectors were used. Unfortunately, balanced-detection increases OCT system size and cost, as it requires many additional components to boost the laser power and maintain near ideal balanced performance across the whole optical bandwidth. Here we show for the first time that a photon detector is capable of achieving shot noise limited performance without using the balanced-detection technique in SS-OCT. We built a system using a so-called electron-injection photodetector, with a cutoff-wavelength of 1700 nm. Our system achieves a shot-noise-limited sensitivity of about −105 dB at a reference laser power of ~350 nW, which is more than 30 times lower laser power compared with the best-reported results. The high sensitivity of the electron-injection detector allows utilization of micron-scale tunable laser sources (e.g. VCSEL) and eliminates the need for fiber amplifiers and highly precise couplers, which are an essential part of the conventional SS-OCT systems.

We investigate the channel length dependence of the electrical characteristics of chemical vapor transport (CVT)-grown MoS 2 nanoribbon (NR) Schottky barrier field-effect transistors to provide insights into the transport properties of such nanostructures. The MoS 2 NRs form spontaneously during the CVT growth, without the application of etching. Back gated transmission line measurement FETs were fabricated on a 45 μ m-long NR with channel lengths ranging between 200 nm and 3 μ m. Contact and sheet resistances were extracted from the electrical measurements and their back-gate bias dependence was analyzed. Numerical modeling based on a virtual probe approach combined with the Landauer formalism shows excellent agreement with the measurements. The model enables a quantitative extraction of the intrinsic FET properties, e.g., mean-free-path and electron mobility, and their dependence on carrier density and investigation of plausible trap distributions. A record electron mobility for a MoS 2 NR channel of ∼ 81 cm 2 / V s was achieved.We investigate the channel length dependence of the electrical characteristics of chemical vapor transport (CVT)-grown MoS 2 nanoribbon (NR) Schottky barrier field-effect transistors to provide insights into the transport properties of such nanostructures. The MoS 2 NRs form spontaneously during the CVT growth, without the application of etching. Back gated transmission line measurement FETs were fabricated on a 45 μ m-long NR with channel lengths ranging between 200 nm and 3 μ m. Contact and sheet resistances were extracted from the electrical measurements and their back-gate bias dependence was analyzed. Numerical modeling based on a virtual probe approach combined with the Landauer formalism shows excellent agreement with the measurements. The model enables a quantitative extraction of the intrinsic FET properties, e.g., mean-free-path and electron mobility, and their dependence on carrier density and investigation of plausible trap distributions. A record electron mobility for a MoS 2...

We report on recent performance breakthroughs in a novel short-wave infrared linear-mode electron-injection-based detector. Detectors consist of InP material system with a type-II band alignment and provide high internal avalanche-free amplification mechanism. Measurements on devices with 10-μm injector diameter and 30-μm absorber diameter show internal dark current density of about 0.1 nA/cm 2 at 160 K. Compared with our previous reported results, dark current is reduced by two orders of magnitude with no sign of surface leakage limitation down to the lowest measured temperature. Compared with the best-reported linear-mode avalanche photodetector, which is based on HgCdTe, the electron-injection detector shows over three orders of magnitude lower internal dark current density at all measured temperatures. Using a detailed simulation with experimentally measured parameters, dark count rate of 1 Hz at 90% photon detection efficiency at 210 K is anticipated. This is a significantly higher operating temperature compared with superconducting detectors with a similar performance.