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Discussion On Device Structures And Hermetic Encapsulation For SiOx Random Access Memory Operation In Air
An edge-free structure and hermetic encapsulation technique are presented that enable SiOx-based resistive random-access memory (RRAM) operation in air. A controlled etch study indicates that the switching filament is close to the SiOx surface in devices with an exposed SiOx edge. Electrical test of encapsulated, edge-free devices in 1 atmosphere air indicates stable switching characteristics, unlike devices with an edge. This work demonstrates that SiOx RRAM is able to operate in air with proper encapsulation and an edge-free structure. The resistive switching failure mechanism when operating in air is explained by the oxidation of hydrogen-complexed defects in the switching filament. (C) 2014 AIP Publishing LLC.National Science Foundation IIP-1127537Microelectronics Research Cente
Characterizing First Arrival Position Channels: Noise Distribution and Capacity Analysis
This paper addresses two fundamental problems in diffusive molecular
communication: characterizing the first arrival position (FAP) density and
bounding the information transmission capacity of FAP channels. Previous
studies on FAP channel models, mostly captured by the density function of
noise, have been limited to specific spatial dimensions, drift directions, and
receiver geometries. In response, we propose a unified solution for identifying
the FAP density in molecular communication systems with fully-absorbing
receivers. Leveraging stochastic analysis tools, we derive a concise expression
with universal applicability, covering any spatial dimension, drift direction,
and receiver shape. We demonstrate that several existing FAP density formulas
are special cases of this innovative expression. Concurrently, we establish
explicit upper and lower bounds on the capacity of three-dimensional,
vertically-drifted FAP channels, drawing inspiration from vector Gaussian
interference channels. In the course of deriving these bounds, we unravel an
explicit analytical expression for the characteristic function of
vertically-drifted FAP noise distributions, providing a more compact
characterization compared to the density function. Notably, this expression
sheds light on a previously undiscovered weak stability property intrinsic to
vertically-drifted FAP noise distributions.Comment: 30 pages; 3 figures, 1 table; this paper is submitted to IEEE
Transactions on Communication
Incorporation of covariates in simultaneous localization of two linked loci using affected relative pairs
<p>Abstract</p> <p>Background</p> <p>Many dichotomous traits for complex diseases are often involved more than one locus and/or associated with quantitative biomarkers or environmental factors. Incorporating these quantitative variables into linkage analysis as well as localizing two linked disease loci simultaneously could therefore improve the efficiency in mapping genes. We extended the robust multipoint Identity-by-Descent (IBD) approach with incorporation of covariates developed previously to simultaneously estimate two linked loci using different types of affected relative pairs (ARPs).</p> <p>Results</p> <p>We showed that the efficiency was enhanced by incorporating a quantitative covariate parametrically or non-parametrically while localizing two disease loci using ARPs. In addition to its help in identifying factors associated with the disease and in improving the efficiency in estimating disease loci, this extension also allows investigators to account for heterogeneity in risk-ratios for different ARPs. Data released from the collaborative study on the genetics of alcoholism (COGA) for Genetic Analysis Workshop 14 (GAW 14) were used to illustrate the application of this extended method.</p> <p>Conclusions</p> <p>The simulation studies and example illustrated that the efficiency in estimating disease loci was demonstratively enhanced by incorporating a quantitative covariate and by using all relative pairs while mapping two linked loci simultaneously.</p
Novel technique of neovagina creation with uterine serosa in the treatment of vaginal agenesis associated with mullerian agenesis
AbstractObjectiveOur aim was to create a neovagina with the least surgical morbidity and the best functional outcome.Materials and methodsWe hereby describe a new technique (Lee's neovaginoplasty) using a combined laparoscopic and vaginal approach in the creation of a neovagina using the uterine serosa layer from the rudimentary uterus and the peritoneum as a graft to line the vagina. This procedure was performed in three patients who were followed-up for a duration of 4 months to 2 years. Vaginal dilation was maintained with a vaginal mold daily for 3 months and three to four times a week thereafter.ResultsAdequate vaginal length of 6-7 cm and width of 2.5 cm was achieved postoperatively. There were no surgical complications and postoperative recovery was fast. Vaginal examination 1 month later showed healthy vaginal tissue with no necrosis or infection. Long-term follow-up did not show any shortening or stenosis of the vagina. Patients were able to have satisfactory sexual intercourse with no pain.ConclusionThe laparoscopic-vaginal approach of using a uterine serosa and peritoneal graft for creation of a neovagina is a simple and effective approach with minimal surgical morbidity that can create a passageway for satisfactory intercourse
Melanogenesis Inhibitor(s) from Phyla nodiflora
Overexpression of tyrosinase can cause excessive production of melanin and lead to hyperpigmentation disorders, including melasma and freckles. Recently, agents obtained from plants are being used as alternative medicines to downregulate tyrosinase synthesis and decrease melanin production. Phyla nodiflora Greene (Verbenaceae) is used as a folk medicine in Taiwanese for treating and preventing inflammatory diseases such as hepatitis and dermatitis. However, the antimelanogenesis activity and molecular biological mechanism underlying the activity of the methanolic extract of P. nodiflora (PNM) have not been investigated to date. Our results showed that PNM treatment was not cytotoxic and significantly reduced the cellular melanin content and tyrosinase activity in a dose-dependent manner (P<0.05). Further, PNM exhibited a significant antimelanogenesis effect (P<0.05) by reducing the levels of phospho-cAMP response element-binding protein and microphthalmia-associated transcription factor (MITF), inhibiting the synthesis of tyrosinase, tyrosinase-related protein-1 (TRP-1), and TRP-2, and decreasing the cellular melanin content. Moreover, PNM significantly activated the phosphorylation of mitogen-activated protein kinases, including phospho-extracellular signal-regulated kinase, c-Jun N-terminal kinase, and phospho-p38, and inhibited the synthesis of MITF, thus decreasing melanogenesis. These properties suggest that PNM could be used as a clinical and cosmetic skin-whitening agent to cure and/or prevent hyperpigmentation
Accuracy of hysteroscopic biopsy, compared to dilation and curettage, as a predictor of final pathology in patients with endometrial cancer
AbstractObjectiveTo compare the methods of transcervical resectoscopy versus dilation and curettage (D&C) for endometrial biopsy and to compare these methods for the percentage of histological upgrades at the final posthysterectomy pathology findings in endometrial cancer.Materials and methodsWe retrospectively reviewed 253 cases of uterine cancer diagnosed from May 1995 to January 2014. Included in the study were patients who received transcervical resectoscopy (TCR) or D&C biopsy as the diagnostic method and underwent laparoscopic staging at our institution. The International Federation of Gynecologists and Obstetricians (FIGO) grade in the pathological report of the biopsy and final hysterectomy were recorded. The extrauterine risk was stratified using the initial FIGO grade and depth of myometrium invasion. It was compared to the actual risk using final pathological findings.ResultsWe identified 203 cases of endometrial cancer; 18 (8.9%) patients had a higher histological grade at the final hysterectomy. Among the 203 patients, 76 patients underwent TCR biopsy and 127 underwent D&C biopsy. The histological grade was upgraded in two (2.6%) patients in the TCR group. Three (3.9%) patients had positive peritoneal washings. In the D&C group, 16 (12.6%) patients with three (2.4%) positive peritoneal washings were upgraded.ConclusionTranscervical resectoscopy could provide more precise grading information, compared to D&C (2.6% vs. 12.6%). Doctors could therefore make a more accurate staging plan, based on the preoperative risk evaluation
3510-V 390-m Omega . cm(2) 4H-SiC Lateral JFET on a Semi-Insulating Substrate
The performance of high-voltage 4H-SiC lateral JFETs on a semi-insulating substrate is reported in this letter. The design of the voltage-supporting layers is based on the charge compensation of p- and n-type epilayers. The best measured breakdown voltage is 3510 V, which, to the authors\u27 knowledge, is the highest value ever reported for SiC lateral switching devices. The R-on of this device is 390 m Omega . cm(2), in which 61% is due to the drift-region resistance. The BV2/R-on is 32 MW/cm(2), which is typical among other reported SiC lateral devices
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