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A mask programmable technology to implement RF and microwave integrated circuits using an array of standard 90-nm CMOS transistors is presented. Using this technology, three wideband amplifiers with more than 15-dB forward transmission gain operating in different frequency bands inside a 4-22-GHz range are implemented. The amplifiers achieve high gain-bandwidth products (79-96 GHz) despite their standard multistage designs. These amplifiers are based on an identical transistor array interconnected with application specific coplanar waveguide (CPW) transmission lines and on-chip capacitors and resistors. CPW lines are implemented using a one-metal-layer post-processing technology over a thick Parylene-N (15 [micro]m) dielectric layer that enables very low loss lines (~0.6 dB/mm at 20 GHz) and high-performance CMOS amplifiers. The proposed integration approach has the potential for implementing cost-efficient and high-performance RF and microwave circuits with a short turnaround time. Index Terms--Amplifiers, coplanar waveguide (CPW), gain-bandwidth product, mask programmable technology, Parylene-N, Si CMOS, transmission line, wideband circuits.

Background: Celiac disease (CD) is a genetically determined autoimmune disease triggered by gluten consumption. Patients with these conditions have intraepithelial lymphocytosis, crypt hyperplasia, and severe intestinal atrophy. Gluten elimination is the only way to reduce this chronic inflammation. The diagnosis of CD is usually made by analyzing anti-tTG, anti-DGP, or EMA serological tests, and it is confirmed by biopsy of the duodenum. In people with CD, xerostomia or dry mouth is a common complication. This condition causes the salivary glands to malfunction and, in turn, may result in oral plaque and periodontal disease. By comparing salivary and serum levels of tissue transglutaminase IgA (tTG-IgA), this study aims to suggest a non-invasive method for diagnosis of CD. Furthermore, the present study evaluates the severity of xerostomia symptoms in people with CD.Methods: In this case-control study, participants were patients referred to the internal ward of Sayyad Shirazi hospital. The control group was selected from healthy people who attended Gorgan Dental College. In this study, an analysis of serum was performed following consent from patients. This was followed by a salivary test, and the results of both tests were compared. The Xerostomia Inventory questionnaire was also used to determine the severity of xerostomia. As part of this study, examination of factors such as total protein concentration of saliva, albumin concentration, amylase level, pH, sodium, calcium, potassium, phosphorus, and interleukin (6, 18, and 21) were conducted.Results: A total of 78 people were studied (aged 15 to 68), 26 were male (33.3%) and 52 were female (66.7%). In comparisons of the serum and saliva of people with and without CD, the level of amylase was higher in the latter group. The average levels of IL-6، IL-18 ،IL-21, and salivary and serum tTG were higher in people with CD. Additionally, CD patients were more likely to develop xerostomia.Conclusion: Study findings showed that CD can reduce certain salivary enzymes and elements, as well as increase inflammatory cytokines, salivary, and serum tTG. The management of dry mouth should also be recommended for celiac disease patients in order to prevent its complications. [ABSTRACT FROM AUTHOR]

In this study, the nuclear structure properties of Tm isotopes with neutron numbers 91, 93, 95, and 97 were investigated using the projected shell model. PSM calculations for doubly-odd Tm nuclei were used to obtain the yrast spectrum. Also, values such as energy transition, a kinetic moment of inertia, and a dynamic moment of inertia were calculated and compared with available experimental data. Angular momentum and frequency at the alignment point are estimated using the moment of inertia. [ABSTRACT FROM AUTHOR]

A 10-GHz filter/receiver module is implemented in a novel 3-D integration technique suitable for RF and microwave circuits. The receiver designed and fabricated in a commercial 0.18-[micro]m CMOS process is integrated with embedded passive components fabricated on a high-resistivity Si substrate using a recently developed self-aligned wafer-level integration technology. Integration with the filter is achieved through bonding a high-Q evanescent-mode cavity filter onto the silicon wafer using screen printable conductive epoxy. With adjustment of the input matching of the receiver integrated circuit by the embedded passives fabricated on the Si substrate, the return loss, conversion gain, and noise figure of the front-end receiver are improved. At RF frequency of 10.3 GHz and with an IF frequency of 50 MHz, the integrated front-end system achieves a conversion gain of 19 dB, and an overall noise figure of 10 dB. A fully integrated filter/receiver on an Si substrate that operates at microwave frequencies is demonstrated. Index Terms--CMOS RF front-end, embedded passives, evanescent-mode cavity filter, heterogeneous integration, packaging, receiver.

This paper presents a compact modeling methodology for inductors and capacitors based on transmission-line theory. Using continued fractions approximation, second- and third-order intrinsic inductor and capacitor models are demonstrated. With the second-order model, one can accurately predict inductor and capacitor behavior up to their first resonance frequencies. With the third-order model, one can match the measured inductor or capacitor response beyond the first resonance frequency. Wideband accurate passive models developed here are essential for transient and harmonic-balance analysis where out-of-band frequencies are important. The model parameters are extracted directly from S-parameter measurement without a need for optimization. Furthermore, the frequency-dependent nonlinear effects of spiral inductors and metal--insulator--metal capacitors are expressed based on simple models without resorting to frequency-dependent parameters. Index Terms--Equivalent-circuit model, integrated passives, lumped elements, metal--insulator--metal (MIM) capacitors, quality factor, self-resonance, spiral inductors.

Toroidal inductors achieve low loss by constraining magnetic flux to a well-defined path and away from ground planes and semiconducting substrates. This paper presents a micro-machined implementation of the toroidal inductor, with focus primarily on microwave integrated circuits on a low-resistivity silicon wafer achieving a Q of 22 and a self-resonant frequency greater than 10 GHz. A verified analytic model is developed. Index Terms--Inductor, micromachining, monolithic microwave integrated circuit (MMIC), radio-frequency integrated circuit (RFIC), toroidal inductor.

This study investigates EFL teachers' perceptions regarding Dynamic Assessment (hereafter DA) prior and subsequent to taking part in workshops and panel discussions. Twenty-five EFL teachers participated in a semi-structured interview, 10 of whom were selected through purposive sampling to take part in a five-session workshop, which was held to familiarize them with the principles of DA. Following workshop training sessions, a panel discussion was run for two sessions and teachers shared their ideas and discussed their problems in applying DA in their classes regarding reading skill. Their classes were video-taped for further analysis and they were also asked to keep reflective journals regarding their practice. After these treatment sessions, a second semi- structured interview regarding EFL teachers' perceptions about DA was run. According to the results of the discussion sessions and interviews, using them as the base of work, an observation checklist was created to assess the EFL teachers' classroom practices and see whether they correspond to their attitudes or not. The results of this study showed that EFL teachers found workshop training sessions both informative and practical. They mentioned panel discussion groups as a good platform to discuss their practice- related problems with their colleagues and writing reflective journals as an awareness raising act which helps them improve their DA practices. Implications for teachers and teacher training courses are discussed. [ABSTRACT FROM AUTHOR]

Fibrosis is a common and mostly progressive pathological outcome in various chronic inflammatory disorders. Dermal (skin) fibrosis, which is associated with intense skin lesions, is a result of an uncontrolled healing process in the dermis, particularly disproportionate fibroblast proliferation and Extracellular Matrix (ECM) production. Animal models are substantial tools in biomedical investigations and have been considerably employed to evaluate miscellaneous features of diseases that cannot be demonstrated otherwise in humans. To date, various skin fibrosis models have been generated, including the transgene and/or genetic models and chemical and drug-induced models. However, genetic models are sophisticated and need access to convoluted methods. Accordingly, the introduction of affordable and easy to generate fibrosis models in the skin is crucial. Here, we aimed to introduce the chemical/druginduced skin fibrosis animal models to provide an updated list of available approaches. [ABSTRACT FROM AUTHOR]