Risky Part Research Articles

Transección de órganos sólidos. Cirugía abierta y laparoscópica

Recent advances in liver surgery have reduced post-hepatectomy mortality to less than 5% in most units specialized in hepato-pancreatic-biliary surgery. Possibly, the single most important factor contributing to these improved results has been the reduction in intraoperative bleeding during liver parenchymal transection. Liver transection is the most risky part of the intervention due to the risk of massive hemorrhage. Some technological advances and refinements to the surgical technique have contributed to making this critical phase of liver surgery safer. Among these advances, the most notable are detailed knowledge of the surgical anatomy of the liver, vascular control techniques and methods of liver parenchymal transection. The present review describes current transection techniques, as well as their advantages and disadvantages. Until there is solid evidence on the best method, the choice of technique and instrument for liver transection depends mainly on the surgeon's personal preference. Nevertheless, some factors can influence the choice of method, such as the surgeon's experience, anesthetic management, type of hepatectomy (central, peripheral), type of approach (open, laparoscopic), quality of the liver (normal, cirrhotic, steatotic) and the availability of the instruments in the center.

A Dynamic Autoregressive Expectile for Time-Invariant Portfolio Protection Strategies

Among the most popular techniques for portfolio insurance strategies that are used nowadays, the so-called Constant Proportion Portfolio Insurance (CPPI) allocation simply consists in reallocating the risky part of a portfolio according to the market conditions. This general method crucially depends upon a parameter - called the multiple - guaranteeing a predetermined floor whatever the plausible market evolutions. However, the unconditional multiple is defined once and for all in the traditional CPPI setting; we propose in this article an alternative to the standard CPPI method, based on the determination of a conditional multiple. In this time-varying framework, the multiple is conditionally determined in order the risk exposure to remain constant, but depending on market conditions. We thus propose to define the multiple as a function of Expected Shortfall. After briefly recalling the portfolio insurance principles, the CPPI framework and the main properties of the conditional or unconditional multiples, we present a Dynamic AutoRegressive Expectile (DARE) class of models for the conditional multiple in a time-varying strategy whose aim is to adapt the current exposition to market conditions following a traditional risk management philosophy. We illustrate this approach in a Time-Invariant Portfolio Protection (TIPP) strategy, as introduced by Estep and Kritzman (1988), which aims to increase the protected floor according to the insured portfolio performance. Finally, we use an option valuation approach for measuring the gap risk in both conditional and unconditional approaches.

Risk supervision in Rochdale

The following describes and discusses the use of a specific form of supervision that attempts to address potentially risky parts of our practice as clinical psychologists.

Why Do Nurses Have a High Incidence of Low Back Disorders, and What Can Be Done to Reduce Their Risk?

Work-related low back disorders (WLBD) are the most frequent and costly musculoskeletal disorder seen, and are related to high working demands. Nurses are among the professionals with the highest rates of WLBD. This paper summarizes the results of research on WLBD among nurses in an acute care teaching hospital. Injury records were reviewed and a questionnaire survey was conducted of 47 nurses from jobs with the highest WLBD incidence rate. The working-life incidence rates of WLBD and point prevalence of low back pain were 65% and 30% for orthopedic nurses and 58% and 25% for intensive care unit (ICU) nurses, respectively. The mean ± standard deviation perceived job exertion on a 10-point scale was 7 ± 2 for the orthopedic nurses and 6 ± 2 for the ICU nurses. Patient transfers (orthopedic nurses) and turning and repositioning patients in bed (ICU nurses) were considered the physically most demanding and risky parts of their occupation. A functional capacity evaluation of 25 nurses and a biomechanical demand analysis of manual handling and patient transfers of 36 nurses were performed. The job simulated forces (78 ± 14% of the maximum) were higher than the preferred force levels (56 ± 21%, P < 0.01). The instantaneous compression at L5/S1 (4754 ± 437 N) and population without sufficient torso strength (37 ± 9%) were highest during the pushing phase of the bed to stretcher transfers by the orthopedic nurses. Evidence-based recommendations for modifications and training programs to reduce the risk of WLBD in nurses have been proposed. Fitness for work, job modifications, and training programs can be designed based on the results presented.

Simultane Behandlung von obliterativen Karotispathologien und koronarer Herzkrankheit

IntroductionCombined carotid artery endarterectomy and coronary artery bypass grafting (C-CABG) has been identified as having a high perioperative risk. Therefore, carotid artery stenting has been recommended. Missing level I evidence on C-CABG as well as carotid stenting has motivated us to review our experience over the past 5 years.Methods and patientsWe report a single centre retrospective study of 113 C-CABG performed between January 2000 and December 2004. The median age of the patients was 65 years (22 patients were 80 years old or older). Carotid endarterectomy was performed first followed by the aortocoronary bypass in the same operation.ResultsThe 30-day mortality was 4.4% (5/113), with no neurological death. The overall neurological complication rate was 3.5% (4/113) due to one stroke that resolved within 30 days, and three TIAs.ConclusionC-CABG with preliminary carotid endarterectomy is a safe technique with a low stroke rate. The risky part of the C-CABG is not the carotid intervention itself but the CABG procedure. Therefore, as long as single carotid artery stenting has not clearly shown early and/or long-term advantages over carotid endarterectomy, it does not seem to be justified in combined carotid and aorto-coronary bypass procedures.

Ankle joint evertor–invertor muscle torque ratio decrease due to recurrent lateral ligament sprains

Objective. To determine an ankle inversion–eversion movement range part where evertor/invertor muscles torque ratio is altered after recurrent ankle lateral ligament sprains. Design. The ankle evertor/invertor muscles torque ratios were determined in the different range parts of angular positions by the muscle isokinetic movements. Background. It is important to determine the movement range part where the evertor muscle weakness after the ankle lateral ligament sprains is more expressed and a repeated trauma of the lateral ligaments is more probable. Methods. Twenty-eight male handball players participated in the tests using an ankle isokinetic inversion–eversion movement investigation dynamometer system. Thirty-three ankle joints were uninjured, but 23 underwent recurrent lateral ligament sprains. Results. The ankle evertor/invertor muscles torque ratio for the sprained ankles was significantly lower in comparison with the uninjured joints in inversion positions at 50° and 60° of the range of movements in all applied velocities, except the slowest movement (30°/s). Conclusions. The recurrent ankle lateral ligament sprains reduced the evertor/invertor muscles torque ratio in the inversion positions of the range of movements and therefore the evertor muscle weakness was more expressed in the beginning of the eversion movement. Relevance An isokinetic dynamometry allows determining the ankle evertor/invertor muscles torque ratio alteration in the different positions of the range of movements and detecting the sprained ankle evertor muscle movement range risky parts. As a result one could elaborate special training programs for the evertor muscles rehabilitation.

The Impact of Market Orientation, Product Advantage, and Launch Proficiency on New Product Performance and Organizational Performance

Some scholars have suggested recently that a market‐oriented culture leads to superior performance, at least in part, because of the new products that are developed and are brought to market. Others have reinforced this wisdom by revealing that a market‐oriented culture enhances organizational innovativeness and new product success, both of which in turn improve organizational performance. These scholars do not reveal, however, through which new product development (NPD) activities a market‐oriented culture is converted into superior performance.To determine how critical NPD activities are for a market‐oriented firm to achieve superior performance, our study uses data from 126 firms in The Netherlands to investigate the structural relationships among market orientation, new product advantage, the proficiency in new product launch activities, new product performance, and organizational performance. We focus on product advantage—because product benefits typically form the compelling reasons for customers to buy the new product—and on the launch proficiency—as the launch stage represents the most costly and risky part of the NPD process. Focusing on the launch stage also is relevant because it is only during the launch that it will become evident whether a market orientation has crystallized into a superior product in the eyes of the customer.The results provide evidence that a market orientation is related positively to product advantage and to the proficiency in market testing, launch budgeting, launch strategy, and launch tactics. Product advantage and the proficiency in launch tactics are related positively to new product performance, which itself is related positively to organizational performance. Market orientation has no direct relationship to new product performance and to organizational performance.An important implication of our study is that the impact of a market orientation on organizational performance is channeled through the effects of a market orientation on product advantage and launch proficiency; subsequently through the effects of product advantage and the proficiency in launch tactics on new product performance; and finally through the effect of new product performance on organizational performance. These channeling effects are much more subtle and complex than the direct relationship of market orientation on organizational performance previously assumed. Another implication of our study is that the impact of a market orientation on performance occurs through the launch activities rather than being pervasive to all organizational processes and activities. A reason for this finding may be that NPD is the one element of the marketing mix that predominantly is the responsibility of the firm, whereas promotion and distribution often are in control of organizations outside the firm (e.g., advertising agencies, major retailers) and whereas the channel or the market often dictates the price. Both implications provide ample opportunities for further research on market orientation and NPD.

'Old Economy' Inputs for 'New Economy' Outcomes: Cluster Formation in the New Silicon Valleys

This paper discusses the results of a two‐year research project on the sources of success in regional clusters of entrepreneurship and innovation like Silicon Valley. Our project has studied a number of locations, most of which have shown spectacular rates of growth of information and communcations technology‐related activities during the 1990s. Our case studies comprise some emerging regions, notably in Ireland, India, Israel and Taiwan, along with more advanced areas like Northern Virginia in the US, Cambridge, UK, the Scandinavian countries and the Silicon Valley 40 years ago by way of the memory of one of its ‘father founders’, Gordon Moore. Through visits, interviews and other materials, we uncovered some regularities about the determinants of success of these entrepreneurial‐led models of economic growth. We find that the economic factors that give rise to the start of a cluster can be very different from those that keep it going. Agglomeration economies, external effects and ‘social increasing returns’ of any sort arise almost naturally after a cluster has taken off. But the most difficult and risky part is to get the new clusters started. At that stage, ‘old economy’ factors like firm‐building capabilities, managerial skills, a substantial supply of skilled labor and connection to markets were crucial for the take off of these ‘new economy’ clusters (including Silicon Valley 40 years ago).

An Asset Allocation Puzzle: Comment

Should the proportion of risky assets in the risky part of an investor’s portfolio depend on the investor’s risk aversion? According to basic financial theory, in particular the mutual-fund separation theorem with a riskless asset, the answer is no. The theorem states that rational investors should divide their assets between a riskless asset and a risky mutual fund, the composition of which is the same for all investors. Risk aversion affects only the allocation between the riskless asset and the fund. However, Niko Canner et al. (1997), CMW hereafter, observed that popular investment advice does not conform to this theory. They reported the stocks, bonds, and cash allocations recommended by four advisors for conservative, moderate, and aggressive investors. As shown in Table 1, which is reproduced from CMW, the advisors recommend a bond/stock ratio that varies directly with risk aversion. For example, Fidelity recommends a bond/stock ratio of 1.50 for a “conservative” (more riskaverse) investor, a ratio of 1.00 for a “moderate” (less risk-averse) investor, and a ratio of 0.46 for an “aggressive” (still less risk-averse) investor. The inconsistency between such advice and the separation theorem is called an asset allocation puzzle by CMW. They attempted to solve the puzzle by relaxing key assumptions in the theory, but finally reached a negative conclusion: “Although we cannot rule out the possibility that popular advice is consistent with some model of rational behavior, we have so far been unable to find such a model” (p. 181). However, they suggested that consideration of intertemporal trading might help resolve the puzzle. In the present paper, we provide theoretical support for the popular advice. The two key insights are that the investor’s horizon may exceed the maturity of the cash asset and that the investor rebalances the portfolio as time passes. If the investor’s horizon exceeds the maturity of cash, which might be a money-market security with maturity of one to six months, then cash is not the riskless asset as is commonly assumed in the basic theory. In a theory allowing portfolio rebalancing, as opposed to a buy-and-hold framework, it is not unreasonable to assume that the investor can synthesize a riskless asset (a zero-coupon bond maturing at the horizon) using a bond fund and cash. Then bonds will be both in the (synthetic) riskless asset and in the risky mutual fund and we show that in this case the theoretical bond/stock ratio varies directly with risk aversion for any hyperbolic absolute risk aversion (HARA) investor. As an example of the type of results that a specific model can produce, we provide a continuous-time model with closed-form solutions, which produces theoretical bond/stock ratios similar to the popular advice. The present paper is organized as follows: in the next section, we analyze the popular advice in terms of the theory of mutual-fund separation of David Cass and Joseph E. Stiglitz (1970). We show that this theory is relevant both in static and dynamic frameworks and use it to analyze the popular advice in complete and incomplete markets. In Section II, we analyze the popular advice in the context of Robert C. Merton’s (1971) continuous-time statement of mutualfund separation and present an illustrative model in which a CRRA investor makes continuous-time portfolio decisions under interest rate and stock price uncertainty. In Section III, numerical results are compared with the popular advice. Section IV is a conclusion. * Bajeux-Besnainou: Department of Finance, School of Business and Public Management, George Washington University, 2023 G Street NW, Washington, DC 20052; Jordan: National Economic Research Associates, 1255 23rd Street NW, Washington, DC 20037; Portait: CNAM and ESSEC, Finance Chair CNAM, 2 Rue Conte, Paris, France. This research was supported by a grant from the Institute for Quantitative Investment Research. We thank two anonymous referees for their comments. 1 HARA functions include quadratic utility, which is one way of justifying mean-variance preferences, and constant relative risk aversion (CRRA) utility. Both quadratic and CRRA utility were considered in the CMW analysis.

Travel and the immunocompromised host.

Increasing opportunities for travel and advances in medicine mean that immunocompromised patients may venture to potentially risky parts of the world. This article examines the risks faced by such travellers. Some limitations of standard travel vaccines are discussed and suggestions are made as to how best to advise such travellers.

Y2K or Bust

Y2K or Bust

Laser hysterofiberscopy v. s. Resectoscpy

[Aim] Resectoscopy and Laser hysteroscopy, both of advanced medical instruments are rapidly expanded into common gynecologic fasilities. Character of resectoscopy (RS) and laser hysterofiberscopy (LHFS) was investigated from the point of basic, clinical, and economic view. [Methods and Results]# Basic Experiment-1: Tissue concentration of inflammatory marker in mouce uterus was measured at the point 1 cm departed from the irradiation with Nd; Yag laser, electric cautery, or cold knife. Leukotrien was used as tissue inflammatory marker. The level at the point with laser irradiation was lower than the point with electric cautery. Cold knife showed the middle level of leukotrien between laser and cautery.# Basic Experiment-2: Distribution of white blood cell of the uterine cervix of the cow was counted at the point irradiated with Nd; Yag Laser or electric cautery. The count with laser irradiation was smaller than the electric cautery.# Clinical investigation-1: The direction of the beam of Nd; Yag laser from LHFS and the cutting way of electric cautery from RS was theoreticary investigated. The beam of the laser from hysterofiberscope runs from the top of the scope end beyond the target tissues. It means laser surgery contains risky part that the top of the beam is not able to wacth with hysterofiberscope. On the other hand, RS is safer method because the direction of cutting way is from distal part to proxismal part (the scope head). But RS surgery is some times more difficult than laser surgery because the sturucture of the RS is rigid# Clinical investigation -2: Operation time of RS or LHFS for submucosal myomectomy was compared RS surgery needs longer time than laser surgery.# Economic comparison: General purchase price for RS and LHFS was compared RS is much more reasonable. LHFS is good instrument. But in order to use LHFS safely, Laparoscopic and intra-abdominal ultrasound guidance is necessary. RS will be more commonly used because RS is safer and cheaper.

A 50 Year Survey and Follow-Up of Silicosis in an Industrial Country: Mineral Exposure and Pneumoconiosis

Abstract Silicosis, a major occupational disease in Sweden for a long time, has been systematically recorded since the early 1930's. After the second World War the medical findings have gradually been supplemented by dust measurements and systematic preventive measures of a technical nature. Particularly dusty working environments, mining, potteries, iron and steel plants have been target areas. In the Swedish Pneumoconiosis Register all reported cases, about 5000, are stored. At the end of the century the number of living workers with silicosis is estimated to be about 1000, and the disease might be eradicated by the years 2030–2040. Technical preventive measures, which have proved to be very successful, have been based on systematic strategies. Specifications have been elaborated for relevant risky parts of the production system, cost efficiency calculations have been made for maintenance and control measures. The cost benefit calculations are now based on the life cycle costs for whole production systems and include benefits in health and safety. This very extensive medical-technical material is briefly reviewed.

Value Function Deployment In A SoftwareProcess

Value Function Deployment In A SoftwareProcess