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Permanent Magnet Synchronous Generator (PMSG) is a type of electric generator where external excitation source is not required to produce a magnetic field because of which it suits underwater electricity generation using Ocean Current Turbines (OCT). Due to the slow speed nature of the OCT, mechanical transmission systems such as gear box, belt drives usually being used to fit the torque — speed characteristics of OCTS with the high speed PMSGs. This results in high starting torque in addition to the transmission losses. To avoid these issues, low speed PMSGs are required to be designed for the speed-torque characteristics of the OCT. This paper briefs the novel methodology to design the low speed PMSGs for the OCT applications and in-house fabrication of a low speed PMSG using the same methodology.

The ocean current energy is one of the clean forms of available renewable energy sources. Based on the topography of the islands, the subsea current is comparatively more than the mainland. Most of the islands are not having self-sustained power sources due to the limitations of infrastructure even though the power requirement is less. The National Institute of Ocean Technology (NIOT) of Ministry of Earth Sciences has undertaken the research and development of an ocean current power module for such islands. The first prototype ocean current turbine (OCT) power module was tested at Macpherson Strait in the Andaman open sea. The subsea power module of the system comprises of the turbine, transmission system, generator and the associated power and instrumentation systems. The development and implementation of electrical and instrumentation system for an underwater OCT power module are one of the challenging task, hence the entire system required to be designed for in-situ conditions. This paper aims to describe the design of Power take off (PTO) system, data acquisition, and wireless communication of prototype ocean current power module trials in open sea conditions.

Private hospitals with nonemployed, volunteer medical staffs face a special challenge in meeting the patient-care needs posed by a mass casualty incident (MCI). Although most disaster response systems focus on emergency department and trauma management, such systems often do not provide for the need to triage existing inpatients to create room for incoming casualties, for continuity of physician care for those patients, as well as for MCI victims in case of major disaster. Such systems must also provide a mechanism for ethical and appropriate rationing of limited resources during a MCI. Community hospitals without 24/7 in-house physicians must provide a mechanism for physician care for patients in situations in which access to the hospital may be limited by the disaster (eg, major earthquake or flood). This article describes a system established at Long Beach Memorial Medical Center, a 740-bed not-for-profit hospital with a volunteer medical staff, to ensure continuity of physician care in a major disaster. To our knowledge, this is the first published report of such a system.

In this study, we report results on a piezoelectric- material-based mechanical energy-harvesting device that was fabricated by combining laser machining with microelectronics packaging technology. It was found that the laser-machining process did not have significant effect on the electrical properties of piezoelectric material. The fabricated device was tested in the low-frequency regime of 50 to 1000 Hz at constant force of 8 g (where g = 9.8 m/s(2)). The device was found to generate continuous power of 1.13 microW at 870 Hz across a 288.5 kOmega load with a power density of 301.3 microW/cm(3).

In the last years, a considerable number of studies have been performed on the correlation between Helicobacter pylori infection and ischaemic heart disease. The reason is the supposed role of some chronic infections in the genesis and development of vessel wall injury and atheromatous plaque, as already reported for Chlamydia pneumoniae and herpes viruses. While this association may be theoretically conceivable, it still remains debated from a practical point of view. Epidemiological and animal studies as well as some eradicating trials gave conflicting results, while studies investigating the specific molecular mimicry mechanisms induced by H. pylori strongly support the association. Moreover, none of the studies performed so far did take into account the effect of the genetic susceptibility to develop ischaemic heart disease or to respond to H. pylori infection. In particular, while the exposure to some known risk factor for atherosclerosis should lead to develop ischaemic heart disease, no condition or exposure, either individual or in combination, completely explains the occurrence and the progression of the disease, as many patients develop ischaemic heart disease in the absence of any risk factor. Based on these concepts, can we state that H. pylori infection may cause the same effect in patients with ischaemic heart disease as in healthy subjects? Further studies are needed in order to clarify this issue.

White matter injury is a known complication of whole brain radiation (WBRT). Little is known about the factors that predispose a patient to such injury. The current study used MR volumetrics to examine risk factors, in particular the influence of pre-treatment white matter health, in developing white matter change (WMC) following WBRT. Thirty-four patients with unilateral metastatic disease underwent FLAIR MRI pre-treatment and at several time points following treatment. The volume of abnormal FLAIR signal in the white matter was measured in the hemisphere contralateral to the diseased hemisphere at each time point. Analyses were restricted to the uninvolved hemisphere to allow for the measurement of WBRT effects without the potential confounding effects of the disease on imaging findings. The relationship between select pre-treatment clinical variables and the degree of WMC following treatment was examined using correlational and regression based analyses. Age when treated and volume of abnormal FLAIR prior to treatment were significantly associated with WMC following WBRT; however, pre-treatment FLAIR volume was the strongest predictor of post-treatment WMCs. Age did not add any predictive value once white matter status was considered. No significant relationships were found between biological equivalent dose and select cerebrovascular risk factors (total glucose, blood pressure, BMI) and development of WMCs. The findings from this study identify pre-treatment white matter health as an important risk factor in developing WMC following WBRT. This information can be used to make more informed decisions and counsel patients on their risk for treatment effects.

Summary The Life cycle concept will become the backbone in a new industrial culture named sustainable production. Sustainability means that products are designed for their whole life cycle i.e. production, distribution, usage and disposal with minimized (acceptable) influence on the environment, occupational health and use of resources. A key element in this new engineering life cycle approach is a method/tool to assess and evaluate environmental, occupational health and resource consequences in all life cycle phases at the product development stage. In this paper a preliminary method for evaluating environmental consequences containing the major environmental effects is presented. The method outlined quantifies the term “environmental friendly” so it can be used as a “yardstick” in evaluating different technical solutions. The complex problems in the final design decisions are discussed and future perspectives outlined.

Excerpt Although earlier writers,1, 2, 3had discussed the syndrome of short P-R intervals and widened QRS complexes, proper clinical evaluation of the problem was not accomplished until the paper o...

To investigate the frequency of unreported concussion and estimate more accurately the overall rate of concussion in high school football players.Retrospective, confidential survey completed by all subjects at the end of the football season.A total of 1,532 varsity football players from 20 high schools in the Milwaukee, Wisconsin, area were surveyed.The structured survey assessed (1) number of concussions before the current season, (2) number of concussions sustained during the current season, (3) whether concussion during the current season was reported, (4) to whom concussion was reported, and (5) reasons for not reporting concussion.Of respondents, 29.9% reported a previous history of concussion, and 15.3% reported sustaining a concussion during the current football season; of those, 47.3% reported their injury. Concussions were reported most frequently to a certified athletic trainer (76.7% of reported injuries). The most common reasons for concussion not being reported included a player not thinking the injury was serious enough to warrant medical attention (66.4% of unreported injuries), motivation not to be withheld from competition (41.0%), and lack of awareness of probable concussion (36.1%).These findings reflect a higher prevalence of concussion in high school football players than previously reported in the literature. The ultimate concern associated with unreported concussion is an athlete's increased risk of cumulative or catastrophic effects from recurrent injury. Future prevention initiatives should focus on education to improve athlete awareness of the signs of concussion and potential risks of unreported injury.

A third family with two Italian neonates affected with limb/pelvis-hypoplasia/aplasia syndrome is reported. The disorder shows autosomal recessive inheritance.

In 1938, Taquini 1 reported that, when the kidney of a dog is made completely ischemic, re-establishment of the renal circulation is followed by a rise in blood pressure. In a previous study, 2 it was found that the expected rise in blood pressure did not occur in rabbits following the termination of complete renal ischemia which had lasted four to six hours. At that time, the only way to account for the difference in the response of dogs and rabbits was to assume a species variation. Because of the negative response in rabbits, it seemed desirable to extend these observations to other animals; in this communication we are reporting the effects upon the blood pressure of re-establishment of the circulation of ischemic kidneys in cats, dogs, and rats.

1. Perfusates of totally ischemic kidneys of cats contain a pressor substance which is not present in the perfusates of normal kidneys, ischemic hind limbs, or ischemic gravid uteri. 2. The pressor material in ischemic renal perfusates originates directly in the kidney as a result of complete ischemia. 3. The pressor principle contained in ischemic renal perfusates is the cause of the hypertension which follows the reestablishment of circulation in completely ischemic kidneys, since perfusates of unreleased completely ischemic kidneys contain more pressor material than perfusates of released ischemic kidneys of the same animal. 4. The pressor principle in ischemic renal perfusates is presumed to be renin for the following reasons, (a) Both substances are destroyed by boiling, (b) Both substances induce tachyphylaxis. (c) The configuration of both pressor curves is identical, (d) The pressor action of both is not reversed by 933F, proving they are not epinephrine-like substances. (e) When incubated with plasma, both form a heat-stable pressor substance. (f) The pressor effect of both is uninfluenced by a previous injection of cocaine, (g) Unreleased, completely ischemic kidneys yield more pressor material on extraction than do released ischemic kidneys of the same animal. 5. The perfusates of blood-free ischemic kidneys contain more renin than those of blood-filled ischemic kidneys. 6. A method is described by which the power of various substances to inhibit or enhance the production of renin in the ischemic kidney may be tested. 7. A small amount of the heat-stable pressor substance, presumably angiotonin or hypertensin, is formed by the reaction of the pressor material (renin) and plasma in the vessels of the kidney during the period of complete ischemia.

The time-course of rod-cone interaction (change of scotopic sensitivity caused by photopic background stimulation) was measured in the presence of briskly exchanged, scotopically matched, 490- and 630-nm background disks. In all conditions, interaction rose and fell quickly with changes of photopic stimulation. When the background was a small 0.6 degree-diameter disk, photopic stimulation produced relatively constant maintained interaction of about 0.6 log units. When the background was a large 7.8 degree-dia disk, photopic stimulation produced larger initial (0.6-1.0 log unit) than maintained (0.2 log unit) interaction. When a 0.6 degree by 7.8 degree annulus was used instead of a background, photopic stimulation produced substantial interaction only at offset, a transitory interaction. Thus, the spatial dependence of transitory interactions differs from that of maintained interaction: transitory interactions can be large even when maintained interaction is small or absent. The results are discussed in terms of a simple center-surround model of rod-cone interaction that unifies both maintained and transient interaction.

The behavior of a Josephson system under pulsed operation is of utmost importance for developing reliable digital devices working at very high clock frequencies. Information about effect of thermal noise over pulsed operation is also useful to design errors free devices. Recent experiments in a system of two stacked junctions show that pulses applied to the first junction (injector) of the stack drive the Josephson biased second junction (detector) in the resistive state. The experiment was interpreted as pulsed-assisted escape toward resistive state as a consequence of an excitation of large non-linear oscillations in the detector junction that, with the contribution of thermal noise, drives out the junction from the zero voltage state. Moreover, an unstability of the resistive state toward the zero voltage state under the same pulsed operation was also noted. By means of a systematic numerical approach to the problem, we present a study of the pulsed-assisted escape using the framework of the thermal escape theory for the direct transition from zero voltage state to resistive state. We study the single junction case and a stacked configuration as examples of different systems showing pulsed-assisted escape. (C) 2002 Elsevier Science B.V. All rights reserved.

Acute hyperinsulinaemia in the absence of changes in blood glucose increases heart rate in man. Animal studies have suggested that beta-adrenergic blockade does not prevent the insulin-induced increase in heart rate. The aim of the present study was to investigate the acute effect of insulin on heart rate and blood pressure in non diabetic subjects and, in particular, to determine whether beta-adrenergic receptor blockade would significantly influence the effect. On separate days 9 healthy young volunteers were pretreated with either 80 mg propranolol or placebo p.o. After a 60-90 min period of heart rate and blood pressure stabilization, a placebo injection was given intravenously and heart rate and blood pressure were then monitored every 5 min. After 30 min insulin Actrapid MC 0.2 IU/kg body weight was given i.v. A 20\% glucose infusion was given to maintain blood glucose at its fasting level. After insulin administration, a rapid and statistically significant increase in heart rate was observed when the patients were pretreated with placebo; pretreatment with propranolol completely prevented this effect. Serum insulin levels were significantly higher than baseline at all times and there was no significant change in blood glucose. The results are consistent with the hypothesis that the insulin-induced increase in heart rate in man may result from stimulation of cardiac sympathetic activity.