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Among the different types of bilayer tunneling field-effect transistors exploiting interband tunneling phenomena with tunneling directions aligned with gate-induced electric fields, the utilization of InAs/GaSb channels proves to be an appealing means to enhance ON-current levels. Ultrathin channel thicknesses make quantum confinement be the agent that closes the broken gap of the InAs/GaSb heterojunction leading to a staggered gap which blocks the tunneling current in the OFF state. In this paper, the gate leakage tunneling current is analyzed as one of the main critical processes degrading the performance of the proposed structure. Appropriate gate stacks of HfO2/Al2O3 combined with gate-to-drain underlaps are shown to effectively suppress this leakage tunneling, while at the same time, preserve an adequate electrostatic control over the channel. Simulation results for the most optimized configurations feature ON-state levels of up to $400\mu \text{A}/\mu \text{m}$ and subthreshold swings of $\approx 3$ mV/dec over more than 7 decades of current.

This work presents an embedded printed antenna with omnidirectional azimuth coverage for automotive applications. A cavity-backed circular patch antenna (CBCPA) is designed to operate as an omnidirectional azimuth coverage, vertically polarized antenna at 2.4 GHz. We introduce the CBCPA design for car wireless communication applications. The CBCPA is embedded in the car roof to reduce any aerodynamic effect, using the rooftop as a ground plane for the proper monopolar radiation pattern generation. This design maintains the performance of the antenna, avoiding back radiation inside the car due to the metallic cavity and metallic rooftop. The design offers a high-efficiency homogeneous pattern in the azimuth. The use of low-profile and lightweight materials into a single cavity-backed configuration is also an advantage of this design that makes it suitable for integration in car platforms. Additionally, the cost of the antenna is reduced compared to other antenna options. This design represents a useful application to monopolar radiation patterns in microstrip technology. In our study, the CBCPA is mounted on a vehicular platform by simulation to validate the antenna characteristics.

Within the research in bilayer tunneling field-effect transistors (TFETs) exploiting interband tunneling phenomena with tunneling directions aligned with gate-induced electric fields, simulation results for the heterogate electron–hole bilayer TFET (HG-EHBTFET) showed that this type of devices succeeded in suppressing the parasitic tunneling leakage currents appearing in EHBTFETs as a result of the variable quantization strength inside the channel. In this paper, and conversely to standard approaches with entirely intrinsic channels, we investigate the possibility of modulating the band-to-band tunneling (BTBT) distance by acting on the subband discretization profiles through partially doped channels. We also analyze the impact of this pocket doping inside the channel on the occupancy probabilities involved in the BTBT processes in a germanium HG-EHBTFET.

Tunnel FETs (TFETs) are in the way to become an alternative to conventional MOSFETs due to the possibility of achieving low subthreshold swing combined with small OFF current levels, which allows operation at low $V_{\mathrm {DD}}$ . In this paper, a nonlocal band-to-band tunneling model has been successfully implemented into a multisubband ensemble Monte Carlo (MS-EMC) simulator and applied to ultrascaled silicon-based n-type TFETs. We have considered two different criteria for the choice of the tunneling path followed by the carriers when crossing the potential barrier, which leads to different distributions of the generated electron–hole pairs. Subband discretization due to field–induced quantum confinement has been considered. TCAD simulations accounting for quantization effects are considered for comparison purposes providing a very accurate agreement with MS-EMC results.

As the scaling of electronic devices approaches to the end of the roadmap quantum phenomena play an important role not only in the electrostatics but also in the electron transport. This work presents the capabilities of a novel implementation of Multi-Subband Ensemble Monte Carlo simulators (MS-EMC) including transport quantum phenomena. In particular, an effective computational scheme of tunneling mechanisms (including S/D tunneling, GLM and BTBT) is shown taking advantage of the main features of semi-classical transport models which are the reduction of the computational requirements and a higher flexibility in comparison to purely full quantum codes.

A former definition states that a brain-computer Interface provides a direct communication channel to the brain without the need for muscles and nerves. With the emergence of wearable and wireless brain-computer interfaces, these systems have evolved to become part of wireless body area networks, offering people-centric applications such as cognitive workload assessment and detection of selective attention. Currently, wireless body area networks are mostly integrated by low-cost devices that, because of their limited hardware resources, cannot generate secure random numbers for encryption. This is a critical issue in the context of new Internet of Things device communication and its security. Such devices require securing their communication, mostly by means of the automatic renewal of the cryptographic keys. In the domain of the people-centric Internet of Things, we propose to use wireless brain-computer interfaces as a secure source of entropy, based on neuro- activity, capable to generate secure keys that outperforms other generation methods. In our approach, current wireless brain-computer interface technology is an attractive option to offer novel services emerged from novel necessities in the context of the people-centric Internet of Things. Our proposal is an implementation of the human-in-the-loop paradigm, in which devices and humans indistinctly request and offer services to each other for mutual benefit.

Summary Aging‐related decline in immunity is believed to be the main driver behind decreased vaccine efficacy and reduced resistance to infections in older adults. Unrepaired DNA damage is known to precipitate cellular senescence, which was hypothesized to be the underlying cause of certain age‐related phenotypes. Consistent with this, some hallmarks of immune aging were more prevalent in individuals exposed to whole‐body irradiation (WBI), which leaves no anatomical repository of undamaged hematopoietic cells. To decisively test whether and to what extent WBI in youth will leave a mark on the immune system as it ages, we exposed young male C57BL/6 mice to sublethal WBI (0.5–4 Gy), mimicking human survivor exposure during nuclear catastrophe. We followed lymphocyte homeostasis thorough the lifespan, response to vaccination, and ability to resist lethal viral challenge in the old age. None of the irradiated groups showed significant differences compared with mock‐irradiated (0 Gy) animals for the parameters measured. Even the mice that received the highest dose of sublethal WBI in youth (4 Gy) exhibited equilibrated lymphocyte homeostasis, robust T‐ and B‐cell responses to live attenuated West Nile virus (WNV) vaccine and full survival following vaccination upon lethal WNV challenge. Therefore, a single dose of nonlethal WBI in youth, resulting in widespread DNA damage and repopulation stress in hematopoietic cells, leaves no significant trace of increased immune aging in a lethal vaccine challenge model.

openaire: EC/H2020/662175/EU//WAYTOGO-FAST Leakage phenomena are increasingly affecting the performance of nanoelectronic devices, and therefore, advanced device simulators need to include them in an appropriate way. This paper presents the modeling and implementation of direct source-to-drain tunneling (S/D tunneling), gate leakage mechanisms (GLMs) accounting for both direct tunneling and trap-assisted tunneling, and nonlocal band-to-band tunneling (BTBT) phenomena in a multissubband ensemble Monte Carlo (MS-EMC) simulator along with their simultaneous application for the study of ultrascaled fully depleted silicon-on-insulator, double-gate silicon-on-insulator, and FinFET devices. We find that S/D tunneling is the prevalent phenomena for the three devices, and it is increasingly relevant for short-channel lengths.

The inclusion of quantum effects in the transport direction plays an important role in the extensive research of ultrascaled electronic devices. In this context, it is necessary to study how these phenomena affect different technological architectures in order to conclude which one can be the best candidate to replace standard technology. This paper presents the implementation of direct source-to-drain tunneling effect in a multisubband ensemble Monte Carlo simulator showing its influence in different structures such as fully depleted silicon-on-insulator, double-gate silicon-on-insulator, and FinFET devices. The differences in the potential profile and the electron distribution in the subbands for these architectures modify the number of electrons affected by this quantum mechanism and, therefore, their short-channel behavior.

This contribution provides the design of a microwave phase shifter for active steerable reflectarray devices at microwave frequencies. The device is based on a 3dB hybrid coupler with three of its ports connected to reflective circuits. This reflective circuit is responsible of the phase variation by means of the use of an electrically controllable microwave varactor. More than 360° phase shifting is obtained with this device as the signal is conducted through the device towards the reflective circuits in three different stages. The input port of the device is also the output one, providing the desired phase shifting and the reflective effect. This device is of great interest in reflectarray applications in order to provide controllable phase shifting at each array element. The document includes the design of the different parts of the shifter along with the device design. Results, considerations and discussion are also provided in this work.

The c-MYC oncogene plays an important role in tumorigenesis and is commonly highly expressed in gastrointestinal cancers. In colon cells, c-MYC is regulated by the adenomatous polyposis coli (Apc) tumor suppressor gene. Multiple intestinal neoplasia (ApcMin/+ or Min) mice are heterozygous for a truncating Apc mutation and serve as a model of familial adenomatous polyposis (FAP) disease. To study the role of c-Myc in the mutant Apc-mediated colon tumorigenesis, we have developed a transgenic mouse with the conditional deletion of the floxed c-Myc alleles in the intestinal crypts of ApcMin/+ mice (ApcMin/+; c-Mycfl/fl). The floxed c-Myc deletion was initiated via a Cre recombinase controlled by the intestine-specific transcriptional regulatory elements of the liver fatty acid-binding protein gene (Fabpl4xat-132). Fabpl4xat-132-mediated Cre expression and recombination resulted in a two-fold decrease in c-MYC protein expression with no effect on intestinal tract morphology. Small intestinal tumorigenesis was significantly suppressed throughout the small intestinal tract of ApcMin/+; c-Mycfl/fl mice compared to c-Myc wild type littermates. In ApcMin/+; c-Mycfl/fl mice, the intestinal apoptosis was higher in the areas of the small intestine with the decreased c-Myc protein expression (P=0.0016, compared to their littermates with the wild type c-Myc). Thus, conditional inactivation of c-Myc, mediated by Fabpl4xat-132-driven Cre-recombinase, suppresses Apc-dependent intestinal tumorigenesis in adult ApcMin/+ mice, without apparent effect on normal intestinal mucosa.

The nonsteroidal antiinflammatory drug sulindac displays chemopreventive activity in patients with familial adenomatous polyposis (FAP). Sulindac metabolites induce apoptosis in colon tumor cells, in part, by a polyamine-dependent mechanism that can be suppressed with exogenous putrescine. To determine the relevance of this mechanism in animals, we treated Apc(Min/+) mice, a model of human FAP, with sulindac alone or in combination with dietary putrescine. Sulindac increased steady-state RNA levels and enzymatic activity of the polyamine catabolic enzyme spermidine/spermine N(1)-acetyltransferase and intestinal levels of monoacetylspermidine, spermidine, and spermine in the small intestine of mice. Sulindac also decreased the activity of the biosynthetic enzyme ornithine decarboxylase but not adenosylmethionine decarboxylase (AMD). Dietary putrescine increased intestinal putrescine contents, whereas the combination of dietary putrescine and sulindac yielded the highest levels of intestinal putrescine and correlated with a statistically significant reduction in AMD enzyme activity. Dietary putrescine did not statistically significantly increase tumorigenesis, although it significantly increased the grade of adenoma dysplasia (P0.05). The effectiveness of sulindac to suppress intestinal carcinogenesis was partially abrogated by dietary putrescine. These data suggest that sulindac exerts at least some of its anticarcinogenic effects in mice via a polyamine-dependent mechanism. Because high concentrations of putrescine can be found in certain dietary components, it may be advantageous to restrict dietary putrescine consumption in patients undergoing treatment with sulindac.

Background: A high-fat diet is a risk factor for the development of inflammatory bowel disease (IBD) in humans. Deoxycholate (DOC) is increased in the colonic contents in response to a high-fat diet. Thus, an elevated level of DOC in the colonic lumen may play a role in the natural course of development of IBD. Methods: Wild-type B6.129 mice were fed an AIN-93G diet, either supplemented with 0.2% DOC or unsupplemented and sacrificed at 1 week, 1 month, 3 months, 4 months, and 8 months. Colon samples were assessed by histopathological, immunohistochemical, and cDNA microarray analyses. Results: Mice fed the DOC-supplemented diet developed focal areas of colonic inflammation associated with increases in angiogenesis, nitrosative stress, DNA/RNA damage, and proliferation. Genes that play a central role in inflammation and angiogenesis and other related processes such as epithelial barrier function, oxidative stress, apoptosis, cell proliferation/cell cycle/DNA repair, membrane transport, and the ubiquitin-proteasome pathway showed altered expression in the DOC-fed mice compared with the control mice. Changes in expression of individual genes (increases or reductions) correlated over time. These changes were greatest 1 month after the start of DOC feeding. Conclusions: The results suggest that exposure of the colonic mucosa to DOC may be a key etiologic factor in IBD. The DOC-fed mouse model may reflect the natural course of development of colitis/IBD in humans, and thus may be useful for determining new preventive strategies and lifestyle changes in affected individuals.

Statement of problem. The use of endosseous implants to support and retain dental prostheses has become a routine treatment option in many dental practices. Although physical, mechanical, and chemical differences exist among implant systems, survival claims are similar. Purpose of study. This review solicited literature from six implant manufacturers that was thought, by their standards, to be pertinent to the validation of their implant system. Methods. The literature was reviewed and categorized. Conclusion. On the basis of the literature supplied by the manufacturers, only one implant system demonstrated scientifically valid long-term success. (J Prosthet Dent 1997;77:271-9.)

This paper presents two multi-system antennas designed for automotive mobile satellite communication applications. The antennas are optimized for the new European S-band mobile satellite systems and in addition they include also the capabilities for GPS and GSM/UMTS bands. The first model implements an S-band Receive-Only radiating element for broadcasting applications while the second contains also an S-band transmit element allowing interactive services via satellite. The achieved structures can be easily installed on cars or integrated in plastic structures of the vehicles. The details of the design of the antennas and a summary of their performances are described.

The active components (phase shifters, LNAs) of a Ku-band direct radiating array are a major part of its cost. A way to reduce this cost is to use simpler control elements. In the frame of ESA project BEST (BEam Switching Transmit-receive mobile user terminal antenna), we have designed, built and measured a receive-only, Ku-band demonstrator using 1-bit phase controls. These controls have been implemented using discrete switches.

Professionals involved in cross-cultural assessment have acknowledged the methodological challenges which they must face when translating and adapting questionnaires developed for a specific linguistic and cultural group. International medical studies have demonstrated that a simple translation of a questionnaire does not ensure data accuracy (Guillemin et al., 1993). Guidelines for adapting tests and questionnaires have been established by the International Test Commission (ITC). The ITC is an association of national psychological associations, test commissions, publishers, and other organizations committed to promoting effective testing and assessment policies and to the proper development, evaluation, and uses of educational and psychological instruments. The ITC Guidelines are intended to orient professionals and users when adapting tests or questionnaires reflecting the technical knowledge gathered in the field (van de Vijver & Hambleton, 1996). The aim of this study is to present the translation of the LittlEARS Auditory Questionnaire into Polish and to get the evidence of the quality of the translated version of the LittlEARS questionnaire.

The c-MYC oncogene plays an important role in tumorigenesis and is commonly highly expressed in gastrointestinal cancers. In colon cells, c-MYC is regulated by the adenomatous polyposis coli (Apc) tumor suppressor gene. Multiple intestinal neoplasia (ApcMin/+ or Min) mice are heterozygous for a truncating Apc mutation and serve as a model of familial adenomatous polyposis (FAP) disease. To study the role of c-Myc in the mutant Apc-mediated colon tumorigenesis, we have developed a transgenic mouse with the conditional deletion of the floxed c-Myc alleles in the intestinal crypts of ApcMin/+ mice (ApcMin/+; c-Mycfl/fl). The floxed c-Myc deletion was initiated via a Cre recombinase controlled by the intestine-specific transcriptional regulatory elements of the liver fatty acid-binding protein gene (Fabpl4xat-132). Fabpl4xat-132-mediated Cre expression and recombination resulted in a two-fold decrease in c-MYC protein expression with no effect on intestinal tract morphology. Small intestinal tumorigenesis was significantly suppressed throughout the small intestinal tract of ApcMin/+; c-Mycfl/fl mice compared to c-Myc wild type littermates. In ApcMin/+; c-Mycfl/fl mice, the intestinal apoptosis was higher in the areas of the small intestine with the decreased c-Myc protein expression (P=0.0016, compared to their littermates with the wild type c-Myc). Thus, conditional inactivation of c-Myc, mediated by Fabpl4xat-132-driven Cre-recombinase, suppresses Apc-dependent intestinal tumorigenesis in adult ApcMin/+ mice, without apparent effect on normal intestinal mucosa.

Nos2 knockout mice were compared to wild-type mice for susceptibility to colitis in response to a diet supplemented with deoxycholate, a bile acid increased in the colon of individuals on a high-fat diet. Wild-type mice fed a fat-related diet, supplemented with 0.2% DOC, develop colonic inflammation associated with increases in nitrosative stress, proliferation, oxidative DNA/RNA damage, and angiogenesis, as well as altered expression of numerous genes. However, Nos2 knockout mice fed a diet supplemented with deoxycholate were resistant to these alterations. In particular, 35 genes were identified whose expression was significantly altered at the mRNA level in deoxycholate-fed Nos2(+/+) mice but not in deoxycholate-fed Nos2(–/–) mice. Some of these alterations in NOS2-dependent gene expression correspond to those reported in human inflammatory bowel disease. Overall, our results indicate that NOS2 expression is necessary for the development of deoxycholate-induced colitis in mice, a unique dietary-related model of colitis.

We evaluated the role of polyamines in arginine-dependent intestinal tumorigenesis in ApcMin/+ mice. Arginine is a substrate for ornithine synthesis and thus can influence polyamine production. Supplementing the diet with arginine increased intestinal and colonic polyamine levels and colonic carcinogenesis. Inhibiting polyamine synthesis with D,L-α-diflouromethylornithine (DFMO) decreased small intestinal and colonic polyamine pools. In mice provided basal diet, but not when supplemented with arginine, DFMO decreased small intestinal tumor number and burden, and increased intestinal apoptosis. In mice provided supplemental arginine in the diet, DFMO induced late apoptosis and decreased tumorigenesis in the colon. DFMO slightly reduced tumor incidence, number, and size while significantly decreasing tumor burden and grade. These changes in colon tumorigenesis did not occur in mice not provided supplemental arginine. Our study indicates that polyamines play unique roles in intestinal and colonic carcinogenesis in ApcMin/+ mice. Inhibition of polyamine synthesis suppresses the arginine-dependent risk of colon tumorigenesis, resulting in apoptosis induction and decreased tumorigenesis, in this murine model. © 2006 Wiley-Liss, Inc.

Arginine is catabolized by NOS2 and other nitric oxide synthases to form nitric oxide. We evaluated the roles of dietary arginine and Nos2 in Apc-dependent intestinal tumorigenesis in Min mice with and without a functional Nos2 gene. NOS2 protein was expressed only in intestinal tissues of ApcMin/+Nos2+/+ mice. NOS3 expression was higher in intestinal tissues of mice lacking Nos2, mainly in the small intestine. When diet was supplemented with arginine (0.2% and 2% in drinking water), lack of Nos2 results in decreased tumorigenesis in both small intestine and colon. In Nos2 knockout mice, supplemental arginine (up to 2%) caused a decrease in small intestinal tumor number and size. The arginine-dependent decrease was associated with an increase in nitrotyrosine formation and apoptosis in the region of intestinal stem cells. Mice expressing Nos2 did not show these changes. These mice did, however, show an arginine-dependent increase in colon tumor number and incidence, while no effect on apoptosis was seen. These changes were associated with increased nitrotyrosine formation in epithelial cells. Mice lacking Nos2 did not show changes in tumorigenesis or nitrotyrosine formation, while demonstrating an arginine-dependent increase in apoptosis. These data suggest that Nos2 and dietary arginine have significant effects on intestinal and colonic tumorigenesis in Min mice. In both tissues, loss of Nos2 is associated with decreased tumorigenesis when mice are supplemented with dietary arginine. In the small intestine, Nos2 prevents the arginine-induced decrease in tumor number and size, which is associated with NOS3 expression and increased apoptosis. In the colon, Nos2 is required for the arginine-induced increase in tumor number and incidence. © 2005 Wiley-Liss, Inc.

A comparative study of the results provided by two strategies for fitting data to Latent Trait Theory Models has been performed. The first, called Total-Persons-Items (TPI), is structured in three phases: 1) assessment of item fit, 2) assessment of person fit; and finally, 3) overall fit of data to the models (items and persons). The second strategy, the Total-Items-Persons (TIP), changes the order of the phases: 1) assessment of person fit, 2) assessment of item fit and, 3) overall fit of data to the models. To verify the results of these two strategies, a set of 30 items, designed to measure religious attitude, was administered to a sample of 821 persons. The Latent Trait Theory Models used were the Partial Credit Model and the Rating Scale Model. The results underline an important difference between the two procedures: the TPI maximizes the number of persons with good fit and the TIP maximizes the number of items with good fit. Moreover, a procedure for controlling the sensitivity of fit to sample size is proposed.

This paper outlines the development of an electronically steerable receive-only antenna array realized within a project funded by the European Space Agency: the NATALIA project. The antenna has been designed for the reception of mobile satellite services in Ku-band and targets the European high-end automotive market. The design of the prototype is based on an innovative polarization agile phased array concept, the antenna is highly compact in size, has a cost-effective buildup, and shows excellent RF-performance.

We propose and validate a novel design methodology for logic circuits that exploits the conduction mechanism and the presence of two independently biased gates (“n-gate” and “p-gate”) of the electron-hole bilayer tunnel field-effect transistor (EHBTFET). If the device is designed to conduct only under certain conditions, e.g., when Vn-gate = VDD and Vp-gate = 0, it then shows an “XOR-like” behavior that allows the implementation of certain logic gates with a smaller number of transistors compared to conventional CMOS static logic. This simplifies the design and possibly results in faster operation due to lower node capacitances. We demonstrate the feasibility of the proposed EHBTFET logic for low supply voltage operation using mixed device/circuit simulations including quantum corrections.