Quantifying Performance in Fading Channels Using the Sampling Property of a Delta Function

We apply the sampling property of a delta function to obtain the probability of error in fading channels. Our approach reduces the integration to a sampling. The sampling point is obtained in terms of fading parameters and the average signal-to-noise ratio (SNR) to provide the closed form solution of the performance

Quantifying Performance in Fading Channels Using the Sampling Property of a Delta Function

We apply the sampling property of a delta function to obtain the probability of error in fading channels. Our approach reduces the integration to a sampling. The sampling point is obtained in terms of fading parameters and the average signal-to-noise ratio (SNR) to provide the closed form solution of the performance

Performance analysis of MIMO-SESS with Alamouti scheme over Rayleigh fading channels

Self-encoded spread spectrum (SESS) is a novel modulation technique that acquires its spreading sequence from the random input data stream rather than through the use of the traditional pseudo-noise code generator. It has been incorporated with multiple-input multiple-output (MIMO) systems as a means to combat fading in wireless channels. In this paper, we present the analytical study of the bit-error rate (BER) performance of MIMO-SESS systems under Rayleigh fading. The BER expressions are derived in closed form, and the veracity of the analysis is confirmed by numerical calculations that demonstrate excellent agreement with simulation results. The performance analysis shows that the effects of fading can be effectively mitigated by taking advantage of spatial and temporal diversities. For example, a 2 × 2 MIMO-SESS system can achieve about 7 dB performance improvement at 10-4 BER over a MIMO PN-coded spread spectrum system

Aspergillus fumigatus Scleritis Associated with Monoclonal Gammopathy of Undetermined Significance

A 68-year-old woman presented with pain in her left eye. Necrosis with calcium plaques was observed on the medial part of the sclera. Aspergillus fumigatus was isolated from the culture of the necrotic area. On systemic work-up including serum and urine electrophoresis studies, the serum monoclonal protein of immunoglobulin G was detected. The patient was diagnosed with monoclonal gammopathy of undetermined significance and fungal scleritis. Despite intensive treatment with topical and oral antifungal agents, scleral inflammation and ulceration progressed, and scleral perforation and endophthalmitis developed. Debridement, antifungal irrigation, and tectonic scleral grafting were performed. The patient underwent a combined pars plana vitrectomy with an intravitreal injection of an antifungal agent. However, scleral and intraocular inflammation progressed, and the eye was enucleated. Aspergillus fumigatus was isolated from the cultures of the eviscerated materials. Giemsa staining of the excised sclera showed numerous fungal hyphae

Efficacy and safety of ginsam, a vinegar extract from Panax ginseng, in type 2 diabetic patients: Results of a double‐blind, placebo‐controlled study

Abstract Aims/Introduction: The efficacy, dose–response relationship and safety of ginsam, a vinegar extract from Panax ginseng, were evaluated in an 8‐week, double‐blind, randomized, placebo‐controlled study in drug‐naïve patients with type 2 diabetes. Materials and Methods: A total of 72 diabetic patients were randomized to receive 1500, 2000 or 3000 mg of ginsam, or placebo daily for 8 weeks (n = 18 in each group). The primary end‐point was the changes from the baseline HbA1c level. The secondary end‐points were the changes of fasting and postprandial 2‐h glucose concentration, and the proportion of patients achieving a reduction in HbA1c >0.5%. Results: In the intention‐to‐treat analysis, ginsam treatment reduced HbA1c level significantly: −0.56 ± 0.25% in the 1500 mg group, −0.31 ± 0.12% in the 2000 mg group, and −0.29 ± 0.11% in the 3000 mg group (all P 0.5% differed significantly between the placebo group (11.1%) and the 1500 mg (27.8%) and 2000 mg (27.8%) groups. No severe adverse events were observed in any group. Conclusions: An 8‐week treatment with ginsam, a vinegar extract from P. ginseng, moderately improved HbA1c level and was well tolerated in type 2 diabetic patients with inadequate glycemic control. This trial was registered with ClinicalTrial.Gov (no. NCT01008163). (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00185.x, 2011

High-Throughput Mutation Profiling Identifies Frequent Somatic Mutations in Advanced Gastric Adenocarcinoma

Background: Gastric cancer is one of the leading cancer types in incidence and mortality, especially in Asia. In order to improve survival, identification of a catalogue of molecular alterations underlying gastric cancer is a critical step for developing and designing genome-directed therapies. Methodology/Principal Findings The Center for Cancer Genome Discovery (CCGD) at the Dana-Farber Cancer Institute (DFCI) has adapted a high-throughput genotyping platform to determine the mutation status of a large panel of known cancer genes. The mutation detection platform, termed OncoMap v4, interrogates 474 “hotspot” mutations in 41 genes that are relevant for cancer. We performed OncoMap v4 in formalin-fixed paraffin-embedded (FFPE) tissue specimens from 237 gastric adenocarcinomas. Using OncoMap v4, we found that 34 (14.4%) of 237 gastric cancer patients harbored mutations. Among mutations we screened, PIK3CA mutations were the most frequent (5.1%) followed by p53 (4.6%), APC (2.5%), STK11 (2.1%), CTNNB1 (1.7%), and CDKN2A (0.8%). Six samples harbored concomitant somatic mutations. Mutations of CTNNB1 were significantly more frequent in EBV-associated gastric carcinoma (P = 0.046). Our study led to the detection of potentially druggable mutations in gastric cancer which may guide novel therapies in subsets of gastric cancer patients. Conclusions/Significance: Using high throughput mutation screening platform, we identified that PIK3CA mutations were the most frequently observed target for gastric adenocarcinoma

A Survey of Diabetic Educators and Patients for the Revision of Korean Food Exchange Lists

BackgroundFood exchange lists are one of the main methods of nutritional education. However, Korean food exchange lists have not been revised since 1994. Therefore, we surveyed the opinions of diabetes educators and patients with diabetes regarding the need for revision of the current food exchange lists.MethodsFor two weeks beginning on 10 March 2008, a 12-item questionnaire regarding the opinion and need for revision of the current food exchange lists was e-mailed to diabetes educators nationwide. Another 15-question survey was administered to patients with diabetes in 13 hospitals located in the Seoul and Gyeonggi regions of Korea.ResultsWe obtained survey responses from 101 diabetes educators and 209 patients; 65 (64.3%) of the educators answered that the current food exchange lists should be revised. The items that needed revision were the glycemic index, addition of new foods and reaffirmation of exchange standard amounts. The patients demanded specific education about choosing appropriate foods, a balanced meal plan, proper snacks, and dining intake.ConclusionOur survey results demonstrate the need to revise the Korean food exchange lists. This process should focus on glycemic index, the addition of new foods and reconfirmation of one exchange reference unit

Android Fat Depot Is More Closely Associated with Metabolic Syndrome than Abdominal Visceral Fat in Elderly People

BACKGROUND: Fat accumulation in android compartments may confer increased metabolic risk. The incremental utility of measuring regional fat deposition in association with metabolic syndrome (MS) has not been well described particularly in an elderly population. METHODS AND FINDINGS: As part of the Korean Longitudinal Study on Health and Aging, which is a community-based cohort study of people aged more than 65 years, subjects (287 male, 75.9±8.6 years and 278 female, 76.0±8.8 years) with regional body composition data using Dual energy X-ray absorptiometry for android/gynoid area, computed tomography for visceral/subcutaneous adipose tissue (VAT/SAT), and cardiometabolic markers including adiponectin and high-sensitivity CRP were enrolled. We investigated the relationship between regional body composition and MS in multivariate regression models. Mean VAT and SAT area was 131.4±65.5 cm(2) and 126.9±55.2 cm(2) in men (P = 0.045) and 120.0±46.7 cm(2) and 211.8±65.9 cm(2) in women (P<0.01). Mean android and gynoid fat amount was 1.8±0.8 kg and 2.5±0.8 kg in men and 2.0±0.6 kg and 3.3±0.8 kg in women, respectively (both P<0.01). VAT area and android fat amount was strongly correlated with most metabolic risk factors compared to SAT or gynoid fat. Furthermore, android fat amount was significantly associated with clustering of MS components after adjustment for multiple parameters including age, gender, adiponectin, hsCRP, a surrogate marker of insulin resistance, whole body fat mass and VAT area. CONCLUSIONS: Our findings are consistent with the hypothesized role of android fat as a pathogenic fat depot in the MS. Measurement of android fat may provide a more complete understanding of metabolic risk associated with variations in fat distribution

Relationship between Vitamin D, Parathyroid Hormone, and Bone Mineral Density in Elderly Koreans

There is controversy regarding definition of vitamin D inadequacy. We analyzed threshold 25-hydroxyvitamin D (25[OH]D) below which intact parathyroid hormone (iPTH) increases, and examined age- and sex-specific changes of 25(OH)D and iPTH, and association of 25(OH)D and iPTH with bone mineral density (BMD) in elderly Koreans. Anthropometric parameters, serum 25(OH)D and iPTH, lumbar spine and femur BMD by dual-energy radiography absorptiometry (DXA) were measured in 441 men and 598 postmenopausal women. iPTH increased below serum 25(OH) of 36.7 ng/mL in men, but failed to reach plateau in women. Femur neck BMD above and below threshold differed when threshold 25(OH)D concentrations were set at 15-27.5 ng/mL in men, and 12.5-20 ng/mL in postmenopausal women. Vitamin D-inadequate individuals older than 75 yr had higher iPTH than those aged ≤ 65 yr. In winter, age-associated iPTH increase in women was steeper than in summer. In conclusion, vitamin D inadequacy threshold cannot be estimated based on iPTH alone, and but other factors concerning bone health should also be considered. Older people seemingly need higher 25(OH)D levels to offset age-associated hyperparathyroidism. Elderly vitamin D-inadequate women in the winter are most vulnerable to age-associated hyperparathyroidism