The effects of ArginMax, a natural dietary supplement for enhancement of male sexual function

This study examines the role of ArginMax, a natural daily dietary supplement, on male sexual function. 25 subjects diagnosed with mild to moderate erectile dysfunction were evaluated over a 4-week period while on ArginMax. Of the 21 subjects that completed the study, 88.9% improved in ability to maintain erection during sexual intercourse and 75.0% improved in satisfaction with their overall sex life. No significant side effects were noted.     

The effect of random vaccine response on the vaccination coverage required to prevent epidemics

The response people have to vaccination varies because their immune systems differ and vaccine failures occur. Here we consider the effect that a random response, independent for each vaccinee, has on the vaccination coverage required to prevent epidemics in a large community. For a community of uniformly mixing individuals an explicit expression is found for the critical vaccination coverage (CVC) and the effect of the vaccine response is determined entirely by the mean E(AB), where A and B, respectively, reflect the infectivity and susceptibility of a vaccinated individual. This result shows that the usual concept of vaccine efficacy, which focuses on the amount of protection the vaccine provides the vaccinee against infection, is not adequate to describe the requirements for preventing epidemics when vaccination affect infectivity. The estimation of E(AB) poses a problem because A and B refer to the vaccine response of the same individual. Similar results are found when there are different types of individual, but now the mean E(AB) may differ between types. However, for a community made up of households it is shown that the CVC also depends on other characteristics of the vaccine response distribution. In practice this means that estimating a single measure of vaccine effectiveness is generally not enough to determine the CVC. For a specific community of households it is found that the vaccination coverage required to prevent epidemics decreases as the variation in the vaccine response increases.     

Noisy recurrent neural networks: the continuous-time case

The classical stochastic analog of the deterministic linear system in engineering is the linear system driven by white noise. As the promise of artificial neural networks in modeling nonlinear systems continues to grow, the need for a stochastic analog with quantitative foundations for analysis and synthesis will increase. This paper presents recent work in this direction, examining recurrent neural nets (RNN driven by white noise. We examine the effect of noise on the typical continuous-time RNN model. First, we perform qualitative analysis establishing uniform boundedness of moments of the neuron states over time. To enable practical application, however, it is necessary to relate these properties to useful measures that can be estimated. We thus subsequently derive bias and variance measures for the noisy RNN with respect to the corresponding deterministic RNN. This has significant practical implications, since net design is nonminimal in the sense that several nets can solve the same problem. The results allow the user to evaluate given RNN for noise performance. The designer can use these results to constrain the design space so that the design satisfies performance specifications whenever possible. An example is provided using the measures derived in this paper to predetermine the best among several RNN designs for a given problem.     

Risk stratification using the Society of Thoracic Surgeons Program

In an era of progressive cost containment and public scrutiny, the wisdom of aggressive surgical therapy for high-risk candidates has been questioned. At our center in the previous 24 months, 728 patients with coronary artery disease were entered into The Society of Thoracic Surgeons national database, and the hospital outcomes plus length of stay were analyzed. Patients were separated according to the predicted mortality based on the groupings in The Society of Thoracic Surgeons database: 0 to 5% (453 patients); 5% to 10% (126 patients); 10% to 20% (96 patients); 20% to 30% (17 patients); and 30% and greater (36 patients). There was a close correlation with the predicted rates of mortality. Importantly, the preoperative risk stratification demonstrated a strong correlation with the significant morbidity and excessive length of stay in the highest-risk groups (predicted risk of 20% to > or = 30%). The incidences of the most common complications in the group with the highest predicted risk (> or = 30%) were 28%, renal failure; 33%, ventilator dependence; and 17%, cardiac arrest. In addition, at short-term follow-up (6 to 8 months), a 24.3% mortality was identified in patients with a predicted mortality that exceeded 20%. These data quantify the risks and morbidities associated with the care of seriously ill patients with coronary artery disease and demonstrate the need for professional and public discussions focusing on the association of a high preoperative risk status and the consumption of resources.     

Learning curve for oesophageal cancer surgery

BACKGROUND: Surgical training and experience are frequently claimed to influence early and late outcome measures. The aim of this study was to examine any improvement in an individual surgeon's performance in one operation over a period of 7 years from initial appointment to date. METHODS: Patients undergoing Ivor Lewis subtotal oesophagectomy performed by a single surgeon between April 1990 and December 1996 were identified from a prospectively compiled oesophageal cancer database. Operating time (abdominal, thoracic and 'one-lung time'), blood loss, transfusion requirements (intraoperative and total), extent of lymphadenectomy (number of lymph nodes sampled), intensive treatment unit (ITU) stay, hospital stay, postoperative morbidity and mortality, pathological stage, grade and survival were recorded. RESULTS: The records of 150 patients were identified for analysis. The cohort was split into five groups, each of 30 patients operated on consecutively. Each of the groups was comparable for age, sex, smoking history, preoperative haemoglobin and creatinine levels, weight loss, American Society of Anesthesiologists' grade, and histological stage and grade of disease. Analysis of the variables pertaining to operation revealed a significant improvement with time including reduced single-lung operating time (P=0.01), reduced blood loss (P=0.03), reduced transfusion requirement (P < 0.0001), reduced ITU stay (P< 0.0001), reduced inpatient stay (P< 0.0001) and an increased yield of lymph nodes (P < 0.0001). CONCLUSION: This study showed a continuing improvement in a surgeon's performance over a 7-year period. With the current trend to shorter training periods there is a case for continuing supervision of the 'fully trained' surgeon within highly specialist units.     

Genetic basis of neurological tumours

Neurological tumours are common neoplasms of both adults and children. Recent studies have begun to delineate the genetic abnormalities that underlie such tumours, and have implicated two classes of genes, oncogenes and tumour suppressor genes. Most investigations have focused on those astrocytomas that affect the cerebral hemispheres of adults, since these are the most common and malignant brain tumours. The high-grade astrocytomas that affect adults, such as glioblastoma multiforme, often have amplification of the epidermal growth factor receptor (EGFR) oncogene and loss of a variety of chromosomal loci that probably harbour tumour suppressor genes. Of the various tumour suppressor gene loci, the p53 gene on chromosome 17p has been studied most closely and has been shown to be mutated in both low- and high-grade astrocytomas. These genetic alterations may provide a means for subdividing astrocytomas into diagnostic categories. For instance, p53 gene mutations occur more commonly in glioblastomas from young adults and women, while EGFR gene amplification is more common in glioblastomas from older adults and men. For the other primary CNS tumours, genetic studies remain in their infancy. The neurocutaneous syndromes, such as neurofibromatosis types 1 and 2, have provided unique insights into neurological oncogenesis. The NF1 gene on chromosomes 17q and its product, neurofibromin, may be important in the formation of neurofibrosarcomas, while the NF2 gene on chromosome 22q and its product, merlin, are probably involved in the formation of schwannomas and other nervous system tumours. The further characterization of these and other neurological tumour genes will undoubtedly illuminate many other areas in neurooncology.     

Design and characterization of asymetrical super-lattice Si/4H-SiC pin photo diode array: a potential opto-sensor for future applications in bio-medical domain

Microsystem Technologies - Photo-sensors are integral part of different bio-medical diagnostic equipment. Each type of bio-molecules possess unique spectral fingerprint in visible wavelength region...     

Favorable influence of ssDNA-functionalized SWCNT on the navigation pattern of C. elegans

Microsystem Technologies - Single-Walled Carbon Nanotubes (SWCNTs) are widely used as potential carriers in drug delivery systems. The objective of this work was to observe the effects of pristine,...     

Multivariability speaker recognition database in Indian scenario

In this paper we describe the collection and organization of the speaker recognition database in Indian scenario named as IITG Multivariability Speaker Recognition Database. The database contains speech from 451 speakers speaking English and other Indian languages both in conversational and read speech styles recorded using various sensors in parallel under different environmental conditions. The database is organized into four phases on the basis of different conditions employed for the recording. The results of the initial studies conducted on a speaker verification system exploring the impact of mismatch in training and test conditions using the collected data are also included. A copy of this database can be obtained from the authors by contacting them.     

Design of an Ultra-Compact and Highly-Sensitive Temperature Sensor Using Photonic Crystal Based Single Micro-Ring Resonator and Cascaded Micro-Ring Resonator

Silicon - In the present report, a photonic crystal based micro-ring resonator (MRR) structure is proposed which is very compact in size and has very fast response and is employed for temperature...