Avoidance Of Failure Research Articles

Meniscal Root Suturing Techniques

Background: Meniscal root tears have attracted increasing interest in recent years. Fixation is an important factor for rehabilitation and avoidance of early failure. Suture fixations have been the most commonly used techniques. The current study aimed to evaluate the maximum failure load of the native meniscal roots (anteromedial, posteromedial, anterolateral, and posterolateral) and of 3 commonly used meniscal root fixation techniques (2 simple stitches, modified Kessler stitch, and loop stitch). Hypotheses: (1) There will be no difference in maximum failure load between the native meniscal roots. (2) The loop stitch will sustain the greatest maximum load to failure, followed by the modified Kessler stitch and the 2 simple stitches. (3) The maximum failure load of the native meniscal roots will not be restored by the tested fixation methods. Study Design: Controlled laboratory study. Methods: The maximum failure load of the 4 human native meniscal roots was evaluated using 64 human meniscal roots. Additionally, the maximum failure load of the 3 fixation techniques was evaluated on 24 meniscal roots: (1) 2 simple stitches, (2) modified Kessler stitch, and (3) loop stitch using a suture shuttle. Results: The average maximum failure load of the native meniscal roots was 594 ± 241 N (anterolateral: 692 ± 304 N; posterolateral: 648 ± 140 N; anteromedial: 407 ± 180 N; posteromedial: 678 ± 200 N). The anteromedial root was significantly weaker than the posterolateral and posteromedial roots (P = .04 and P = .01, respectively). Regarding fixation techniques, the maximum failure load of the 2 simple stitches was 64.1 ± 22.5 N, the modified Kessler stitch was 142.6 ± 33.3 N, and the loop was 100.9 ± 41.6 N. None of the fixation techniques recreated the strength of the native roots. Conclusion: The native anterolateral root was the strongest meniscal root, and the anteromedial root was the weakest meniscal root. Regarding primary fixation strength, the modified Kessler stitch was the strongest technique compared with the loop and the 2 simple stitches. Clinical Relevance: None of our tested fixation methods restored the strength of native meniscal roots. Thus, rehabilitation after meniscal root fixation should proceed cautiously.

Tree species identity and interactions with neighbors determine nutrient leaching in model tropical forests

An ecosystem containing a mixture of species that differ in phenology, morphology, and physiology might be expected to resist leaching of soil nutrients to a greater extent than one composed of a single species. We tested the effects of species identity and plant-life-form richness on nutrient leaching at a lowland tropical site where deep infiltration averages >2 m year(-1). Three indigenous tree species with contrasting leafing phenologies (evergreen, dry-season deciduous, and wet-season deciduous) were grown in monoculture and together with two other life-forms with which they commonly occur in tropical forests: a palm and a giant, perennial herb. To calculate nutrient leaching over an 11-year period, concentrations of nutrients in soil water were multiplied by drainage rates estimated from a water balance. The effect of plant-life-form richness on retention differed according to tree species identity and nutrient. Nitrate retention was greater in polycultures of the dry-season deciduous tree species (mean of 7.4 kg ha(-1) year(-1) of NO(3)-N lost compared to 12.7 in monoculture), and calcium and magnesium retention were greater in polycultures of the evergreen and wet-season deciduous tree species. Complementary use of light led to intensification of soil exploitation by roots, the main agent responsible for enhanced nutrient retention in some polycultures. Other mechanisms included differences in nutrient demand among species, and avoidance of catastrophic failure due to episodic weather events or pest outbreaks. Even unrealistically simple multi-life-form mimics of tropical forest can safeguard a site's nutrient capital if careful attention is paid to species' characteristics and temporal changes in interspecific interactions.

The effect of SOX on small auditor exits and audit quality

We find that over six hundred auditors with fewer than 100 SEC clients exit the market following SOX. Compared to the non-exiting auditors, the exiting auditors are lower quality, where quality is gauged by: (1) avoidance of AICPA peer reviews and failure to comply with PCAOB rules, and (2) severity of the peer review and inspection reports. In addition, clients of exiting auditors receive higher quality auditing from successor auditors, as captured by a greater likelihood of receiving going concern opinions. Our results suggest that the PCAOB inspections improve audit quality by incentivizing low quality auditors to exit the market.

Acute right ventricular failure after pediatric cardiac transplant: Predictors and long-term outcome in current era of transplantation medicine

To identify pretransplant factors associated with postprocedural right ventricular failure and the relationship between right ventricular failure and long-term survival in children. Records were reviewed for children having heart transplantation from 2000 to 2006. Right ventricular failure was identified by clinical and echocardiographic parameters in 33/129 (25%) recipients: dilated cardiomyopathy in 14/90 (15%), congenital heart disease in 11/27 (41%), and restrictive cardiomyopathy in 8/12 (66%). In 9 of 12 (75%), known elevated (reactive) pulmonary vascular resistance progressed to right ventricular failure. In a further 23/117 (20%) recipients, pulmonary vascular resistance within predefined acceptable range progressed to right ventricular failure. Multiple logistic regression analyses indicated elevated pulmonary vascular resistance (odds ratio 12.30; 95% confidence interval 2.73, 55.32; P = .001) and primary diagnosis, restrictive cardiomyopathy (odds ratio 9.21; 95% confidence interval 2.07, 41.12; P = .004), and congenital heart disease (odds ratio 4.07; 95% confidence interval 1.36, 12.19; P = .012) were strongly associated with right ventricular failure, but duration of heart failure, pretransplant mechanical support, donor status, and ischemic times were not. Treatment included inhaled nitric oxide in 28 (84%), mechanical support in 10 (31%), hemofiltration in 13 (40%), and retransplantation in 2. A Cox multiple regression model including: primary diagnosis, right ventricular failure, and elevated pulmonary vascular resistance indicated that only the latter was independently linked with eventual mortality (hazards ratio 5.45; 95% confidence interval 1.36, 21.96; P = .017). Primary diagnosis and pretransplant elevated reactive pulmonary vascular resistance are both linked to the evolution of right ventricular failure. Pulmonary vascular resistance assessment in end-stage heart failure is challenging; therefore, avoidance of right ventricular failure may not always be possible. Aggressive early treatment may mitigate the effects of right ventricular failure: pretransplant elevated pulmonary vascular resistance was independently associated with long-term survival, but right ventricular failure was not.

Xylem hydraulic safety margins in woody plants: coordination of stomatal control of xylem tension with hydraulic capacitance

Summary 1. The xylem pressure inducing 50% loss of hydraulic conductivity due to embolism (P50) is widely used for comparisons of xylem vulnerability among species and across aridity gradients. However, despite its utility as an index of resistance to catastrophic xylem failure under extreme drought, P50 may have no special physiological relevance in the context of stomatal regulation of daily minimum xylem pressure and avoidance of hydraulic failure under non‐extreme conditions. Moreover, few studies of hydraulic architecture have accounted for the buffering influence of tissue hydraulic capacitance on daily fluctuations in xylem pressure in intact plants. 2. We used data from 104 coniferous and angiosperm species representing a range of woody growth forms and habitat types to evaluate trends in three alternative xylem hydraulic safety margins based on features of their stem xylem vulnerability curves and regulation of daily minimum stem water potential (Ψstem min) under non‐extreme conditions: (i) Ψstem min − P50, (ii) Ψstem min − Pe, the difference between Ψstem min and the threshold xylem pressure at which loss of conductivity begins to increase rapidly (Pe) and (iii) Pe − P50, an estimate of the steepness of the vulnerability curve between Pe and P50. Additionally, we assessed relationships between xylem capacitance, species‐specific set‐points for daily minimum stem water potential and hydraulic safety margins in a subset of species for which relevant data were available. 3. The three types of hydraulic safety margin defined increased with decreasing species‐specific set‐points for Ψstem min, suggesting a diminishing role of stem capacitance in slowing fluctuations in xylem pressure as Ψstem min became more negative. The trends in hydraulic safety were similar among coniferous and angiosperm species native to diverse habitat types. 4. Our results suggest that here is a continuum of relative reliance on different mechanisms that confer hydraulic safety under dynamic conditions. Species with low capacitance and denser wood experience greater daily maximum xylem tension and appear to rely primarily on xylem structural features to avoid embolism, whereas in species with high capacitance and low wood density avoidance of embolism appears to be achieved primarily via reliance on transient release of stored water to constrain transpiration‐induced fluctuations in xylem tension.

Non-invasive ventilation after extubation in hypercapnic patients with chronic respiratory disorders: randomised controlled trial

Non-invasive ventilation can prevent respiratory failure after extubation in individuals at increased risk of this complication, and enhanced survival in patients with hypercapnia has been recorded. We aimed to assess prospectively the effectiveness of non-invasive ventilation after extubation in patients with hypercapnia and as rescue therapy when respiratory failure develops. We undertook a randomised controlled trial in three intensive-care units in Spain. We enrolled 106 mechanically ventilated patients with chronic respiratory disorders and hypercapnia after a successful spontaneous breathing trial. We randomly allocated participants by computer to receive after extubation either non-invasive ventilation for 24 h (n=54) or conventional oxygen treatment (n=52). The primary endpoint was avoidance of respiratory failure within 72 h after extubation. Analysis was by intention to treat. This trial is registered with clinicaltrials.gov, identifier NCT00539708. Respiratory failure after extubation was less frequent in patients assigned non-invasive ventilation than in those allocated conventional oxygen therapy (8 [15%] vs 25 [48%]; odds ratio 5.32 [95% CI 2.11-13.46]; p<0.0001). In patients with respiratory failure, non-invasive ventilation as rescue therapy avoided reintubation in 17 of 27 patients. Non-invasive ventilation was independently associated with a lower risk of respiratory failure after extubation (adjusted odds ratio 0.17 [95% CI 0.06-0.44]; p<0.0001). 90-day mortality was lower in patients assigned non-invasive ventilation than in those allocated conventional oxygen (p=0.0146). Early non-invasive ventilation after extubation diminished risk of respiratory failure and lowered 90-day mortality in patients with hypercapnia during a spontaneous breathing trial. Routine implementation of this strategy for management of mechanically ventilated patients with chronic respiratory disorders is advisable. IDIBAPS, CibeRes, Fondo de Investigaciones Sanitarias, European Respiratory Society.

Spontaneous Rupture of the Intrahepatic Bile Duct due to Carcinoma of the Ampulla of Vater: A Case Report

We reported the first case of spontaneous rupture of the intrahepatic bile duct due to carcinoma of the ampulla of Vater. The patient was a 67-year-old male and he visited the hospital in a pre-shock state. He was diagnosed as panperitonitis and an emergency operation was performed on that day. A laparotomy revealed ascetic fluid containing bile to be retained in the abdominal cavity. Intraoperative cholangiography showed a complete obstruction of the lower common bile duct and the rupture of the intrahepatic (S3) bile duct. A lateral segmentectomy of the liver was performed, followed by T-tube biliary drainage. A two-stage checkup/operation was planned for treatment of the obstruction of the common bile duct. Endoscopic retrograde cholangiography (ERC) performed postoperatively revealed a mass in the ampulla of Vater causing a marked stricture of the common bile duct in that region. A pylorus-preserving pancreaticoduodenectomy including a regional lymphadenectomy was performed about 5 months after the initial operation. There has been no other reports documenting a two-stage operation for the resection of a malignant tumor after treatment with bile peritonitis . The avoidance of sepsis and multiple organ failure via surgical treatment directed against bile peritonitis at the appropriate time is considered optimal strategy to save the life of a patient with this condition.

Avoidance of Perioperative Acute Renal Failure: Land in Sight?

To the Editor: —Acute renal failure (ARF) is a severe perioperative complication and, until today, strategies to avoid it remain controversial.1Kheterpal et al. 2performed an informative retrospective analysis on this topic, underlining the impact of perioperative ARF on patient mortality. Moreover, they identified several independent predictors of ARF in noncardiac surgery. To have them in mind will be useful for our daily practice.However, the authors’ conclusions regarding intraoperative risk factors drawn in the abstract, despite being markedly attenuated in the main text, seem somewhat misleading to us, especially in combination with the title announcing a study on “Patients with Previously Normal Renal Function.”2To prevent general confusion regarding the perioperative use of vasopressors and diuretics, it is important to clearly stress that one major shortcoming limits a direct transfer of the findings to the healthy individual: More than 65,000 patients were primarily screened to evaluate the propensity of patients with certain risk factors to ARF. Unfortunately, not only those 6,534 patients without preoperative renal function measures were excluded from the study,3but in addition 25,537 outpatient cases. In all, the investigators excluded the healthier part of their primary collective. To draw an overall conclusion questioning the use of vasopressors and diuretics in healthy patients from this preselected collective seems a bit overreaching to us. But a careful look into their subgroup analysis does not lower our concerns: In the low-, medium-, and medium–high-risk groups, only 0.8% of the patients receiving vasopressors and 1.5% of the patients receiving diuretics developed ARF. The authors themselves state that ARF occurs in 1–5% of all hospitalized patients,2meaning that diuretics seem to have no influence and that vasopressors seem to even lower the risk of ARF. This picture is slightly changed when taking the high-risk patients into account. However, even now, the overall risk (vasopressors 4.8% and diuretics 2.3%) is still within the range anticipated in hospitalized patients.2To make such a striking statement in the abstract is an unnecessary overinterpretation and falls short of this otherwise very well-performed retrospective analysis.In addition, an extremely interesting finding is only scarcely discussed by the authors: Urine output was not associated with ARF in this study. Eighty-eight percent of the patients not developing ARF had a urine output of less than 0.5 ml · kg−1· h−1, surprisingly significantly more patients than those with ARF (75%). Above that, mean urine production in patients developing ARF was not significantly different from that in the other patients. This is in clear contrast to the common assumption that “logic suggests”1urine output has to be maintained above a certain level to prevent ARF and, therefore, should be treated with crystalloid boluses.4From our point of view, the authors made an important contribution to the current discussion on the practicability of a modern approach to perioperative fluid therapy, aiming at limiting the total crystalloid amount to reduce perioperative complications.5We would like to congratulate Kheterpal et al. on this interesting retrospective analysis. Their work not only will contribute to our patient’s safety, but, more importantly, it marks several starting points for further prospective investigations.*Ludwig-Maximilians University Munich, Munich, Germany. matthias.jacob@med.uni-muenchen.de

Motivational correlates of need for cognition

AbstractNeed for cognition is usually characterized as an intrinsic desire to engage in challenging intellectual activity. In achievement situations, however, it could be associated with more extrinsic goals such as success or the avoidance of failure. Three experiments examined this possibility. Participants in all studies were led to believe they would perform either an easy or a difficult intellectual task that they were likely to fail. After inducing this expectation, indices of extrinsic motivation were obtained. Participants with high need for cognition became more motivated to avoid negative consequences of their behavior (e.g., failure) when they expected the task they would perform to be difficult. In contrast, participants with low need for cognition were not appreciably affected by these expectancies. The anticipation of engaging in intellectual activity apparently stimulates different motives in people with high and low need for cognition, and the mindset induced by these motives influences their later behavioral decisions. Copyright © 2008 John Wiley &amp; Sons, Ltd.

Problem frames and software engineering

In welcoming this issue of Expert Systems, I would like to take the opportunity to remark on a relationship between the problem frames approach to software engineering and some practices of established engineering branches. Common use of the phrase ‘software engineering’ dates from 1967, when a NATO Science Committee Study Group recommended the holding of a working conference by that name. The name was deliberately provocative ‘in implying the need for software manufacture to be based on the types of theoretical foundations and practical disciplines that are traditional in the established branches of engineering’. The proposed conference was held in 1968, and a follow-up conference in 1969. In some respects software has made huge strides in the past 40 years, and software systems are available today that would have been scarcely thinkable in 1967. But in some other respects the original motivation of the NATO conferences has been neglected. Software development has learned remarkably little from the established branches of engineering. Indeed, their proffered lessons were ignored even in the two NATO conferences themselves: a scan of the conference reports shows that with one possible exception – Doug McIlroy's plea for standard, off-the-shelf software components – no substantial attention was paid either to their theoretical foundations or to their practical disciplines. The problem frames approach to software development could be regarded as an attempt, both in original intention and in the path taken by subsequent work on the topic, to learn at least one lesson from the established engineers. This lesson is the importance of what Walter Vincenti calls normal design. An engineer practising normal design already knows the standard form of the device or product to be designed, how its parts fit together, and the operational principle by which it will achieve its purpose. By faithfully following normal practice the engineer can have a good degree of confidence that the result will be successful. In the software context, the standard subproblem classes proposed by the problem frames approach – workpieces, information display, required behaviour and so on – can be regarded similarly, as categories of objects of normal design in which well-established and well-understood precedents can govern both the form of the product and the development practices from which it emerges. Failure is a matter to which established engineering branches pay a great deal of attention. Success comes from experience, it is said, and experience comes from failure. One vital aspect of normal design practice is a twofold approach to the avoidance of failure. First, the standard normal design itself embodies important lessons from past failures. Even when awareness of particular dramatic failures has faded in the collective consciousness of the design engineers, the design choices devised to avoid those failures remain part of the normal product design, and work to prevent a repetition. Second, normal design practice specifically includes knowledge of respects in which designs of the product class in question can still be liable to fail. For example, ever since the dramatic collapse of the Tacoma Narrows Bridge in 1940, designers of suspension bridges are very well aware of the danger of failure due to vertical oscillation of a shallow and narrow roadbed: they do not regard their design work as complete until this danger has been explicitly considered and excluded. In a similar fashion, the repertoires of subproblem and composition concerns identified in the problem frames approach point up likely possibilities of failure, and demand to be explicitly addressed as an integral part of the design work. The four papers in this journal issue relate problem frames to four very different technologies of software engineering. Each is worth careful reading in itself as an individual contribution. Further, their variety offers some confirmation that the ideas underlying the problem frames approach have a broad import, and augurs a fruitful future.

Optimizing Antipseudomonal Therapy in Critical Care

Pseudomonas aeruginosa is a common and important pathogen in the critically ill. It combines environmental hardiness with genomic plasticity and is well adapted to the various niches available in the intensive care unit (ICU). Unresolved arguments over the value of dual versus monotherapy relate primarily to rapidity of killing and to the avoidance of therapeutic failure due to antibiotic resistance. Increasing resistance to conventional antibiotics means that we need to be aware of the factors that promote the success of this pathogen in the ICU, and of emerging alternative strategies. This review focuses on an understanding of the underlying issues and on the practical aspects of prescribing, particularly in the ICU.

Use of Bayesian Net Benefit Regression Model to Examine the Impact of Generic Drug Entry on the Cost Effectiveness of Selective Serotonin Reuptake Inhibitors in Elderly Depressed Patients

Since their invention in the late 1980s and early 1990s, selective serotonin reuptake inhibitors (SSRIs) have become the primary form of pharmaceutical treatment for depression. As the patents of several top-selling SSRIs have expired or are soon to be expired, the SSRI market is expected to witness an increasing share of generic SSRIs. We explored the impact of generic drug entry on the cost effectiveness of SSRIs. Using Medicare MarketScan claims data, we compared the cost effectiveness of sertraline, citalopram, escitalopram and fluoxetine with paroxetine in elderly depressed patients, before and after the entry of generic paroxetine. We followed users of SSRIs for 6 months, starting from the date of their first prescription of an SSRI. For each patient, we measured costs (C(i)) as total medical costs and quantified effectiveness (E(i)) as the avoidance of treatment failure, which was defined as having a break exceeding 45 days in the use of antidepressants. We then calculated individual net benefit as lambda x E(i)- C(i) and employed both net benefit and Bayesian net benefit regression models to examine the impact of generic paroxetine on the cost effectiveness of the other four SSRIs compared with paroxetine, while controlling for patients' sociodemographic characteristics, co-morbidities and patterns of medication switch. Deterministic analysis showed that paroxetine was dominated by most SSRIs prior to the availability of generic paroxetine, and that, after the entry of generic paroxetine, citalopram and escitalopram were dominated by paroxetine. Net benefit regression analysis found that, at a number of lambda values ($US1000, $US5000 and $US10,000), sertraline and escitalopram were more cost effective than paroxetine in the pre-generic-entry period but not in the post-entry period, although the difference in net benefit between the two SSRIs and paroxetine was not statistically significant in both periods. The Bayesian net benefit regression analysis reached similar conclusions. At lambda = $US5000, the probability that sertraline, citalopram, escitalopram or fluoxetine was more cost effective than paroxetine was 96.7%, 77.6%, 96.3% and 97.0%, respectively, in the pre-entry period in the pooled analysis. These probabilities reduced to 36.7%, 62.7%, 33.0% and 60.1%, respectively, in the post-entry period. The probabilities became 94.1%, 71.9%, 89.1% and 92.1% in analysis using the pre-entry data as a prior to update the post-entry data rather than using the pooled data. Using generic drug entry as an example, our study demonstrated the importance of including the economic life cycle of pharmaceuticals in cost-effectiveness analyses. Additionally, the proposed Bayesian framework not only preserves the advantages of the net benefit regression framework, but more importantly, it introduces the possibility of conducting probabilistic cost-effectiveness analyses with claims data.

Policy failure and corruption in Belgium: Is federalism to blame?

Throughout the 1990s, corruption cases, policy failure and scandals tarnished Belgium's international reputation. In this article, we analyse the effect of federalism and political culture on corruption and policy failures and their impact on the likelihood of such occurrences becoming scandals. Survey material suggests that there are few differences between French- and Dutch-speakers in the perception and tolerance of corruption. We then list a number of variables that can explain corruption in Belgium and argue that the independent effect of federalism is very limited. Next we demonstrate that federalism has played a much more significant role in lowering the risk of policy failure, while at the same time creating a few new vulnerabilities. Finally, we argue that the regional political elites do not often engage in policy learning and frequently put forward federalism as the main solution to the avoidance of policy failure and scandal. In this sense, regional political elites do not seize the opportunity for policy experimentation and transfer that is generally seen as one of the main virtues of a federal system of government.

Design, modeling, fabrication and testing of a MEMS capacitive bending strain sensor

Presented herein are the design, modelling, fabrication and testing of a MEMSbased capacitive bending strain sensor utilizing a comb drive. This sensor is designed to be integrated with a telemetry system that will monitor changes in bending strain to assist orthopaedic surgeons with the diagnosis of spinal fusion. ABAQUS/CAE version 6.5 finite element analysis (FEA) modelling software was used to predict sensor actuation, capacitance output and the avoidance of material failure. Highly doped boron silicon wafers with a low resistivity were fabricated into an interdigitated finger array employing deep reactive ion etching (DRIE) to create 150 µm sidewalls with 25 µm spacing between the adjacent fingers. For testing, the sensor was adhered to a steel beam, which was subjected to four-point bending. This mechanically changed the spacing between the interdigitated fingers as a function of strain. As expected, the capacitance output increased as an inverse function of the spacing between the interdigitated fingers, beginning with an initial capacitance of 7.56 pF at the unstrained state and increasing inversely to 17.04 pF at 1571 µε of bending strain. The FEA and analytical models were comparable with experimental data. The largest differential of 0.65 pF or 6.33% occurred at 1000 µε.

Off line simulation system of machining processes

The primary objective for modeling of machining processes is to develop a predictive capability of machining performance in order to facilitate effective planning of machining operations. This capability leads to faster implementation, higher performance, quality at a lower cost. This comes about due to improved selection of machining parameters, optimal fixture design and the avoidance of tool failure. The simulation system presented simultaneously considers the effect of cutter geometry, the cutter's initial position errors, workpiece geometry, machine tool dynamics, and workpiece/fixture system dynamics on the machining process. The integration of all of the above in one model provides an off-line tool to simulate and optimize the machining parameters and the fixture configuration cutting both lead and production time. The modular nature of the simulation system presented allows for the study of many different machining processes. The cutting forces in this system are modeled using a mechanistic approach. NURBS curves and surfaces are utilized for the geometric modeling and simulation of the machining process. While a finite element method is used to model and analyze the workpiece/fixture dynamics. Two case studies are presented to demonstrate the practical application of the presented simulation. The first case presents the optimization of the fixture configuration of a generic automotive component. While the second case presents the results of simulations performed on a novel mill/grind machining process. This process is a combination of face milling and grinding in one operation. Some simulated results are presented along with experimental validation.

Failure analysis of styrene reactor tubes

The analysis of failure of the styrene reactor tubes made of stainless steel has been reported where the tubes contained catalyst as well as ethyl benzene in vapour form along with superheated steam at 570 °C. The tubes were exposed to flue gases causing heating of tubes to 790 °C in the upper part where cracking and failure were mostly noticed. The studies included microstructural examinations of cracked and uncracked tubes, fracture surface investigations and estimation of creep rupture strength, etc. The degradation in microstructure such as extensive grain coarsening, sigma phase formation, carbide formation along grain boundaries, etc., led to development of cracks/voids within the grains and along the grain boundaries and also excessive oxidation of tubes. Possible chemical attack by the feed on the inner surface of tubes further deteriorated the tube life. Suggestions for avoidance of failure have been listed.

Achievement Goal Orientations, “Oughts,” and Self-Regulation in Students with and without Learning Disabilities

The purpose of the present study was to evaluate the regulation of goal orientations and strong “oughts” in students with learning disabilities (LD). Participants were 132 Greek students with state-identified LD using the achievement-discrepancy criterion, and 538 typical students. The first hypothesis tested was that feeling obliged to engage in an activity is grounded on fear and is associated with a network of avoidance-related behaviors. Results confirmed this hypothesis, as the ought-self explained significant amounts of variability in task avoidance, performance avoidance, and fear of failure. The second hypothesis was that the ought-self was associated with failure to regulate. Student groups were formed based on their adoption of mastery, performance approach, task avoidance, multiple-approach goals, and strong “oughts.” Results indicated that students with strong “oughts” persisted significantly less than students with approach forms of motivation. Regardless of their lack of persistence, however, students with strong “oughts” were not inferior in achievement, nor did they display heightened negative affect. By modeling the relationship between goals, achievement and psychopathology, results showed that the ought- self was negatively associated with achievement and positively associated with indices of anxiety and depression. Mean group analyses pointed to salient differences between students with and without LD on motivation, achievement and psychopathology.

Information Disclosure and the Regulation of Traded Product Risks

Various forms of information disclosure such as labelling requirements, hazard warning and prior informed consent are increasingly being used in the regulation of products that are traded across boundaries. In the context of GATT/WTO jurisprudence, in particular, informational mechanisms are seen as more likely to survive challenge than more traditional regulatory methods such as export and import bans. Even then, there may be legal problems, especially where information requirements relate to production methods as well as to the products themselves. There are a number of distinct normative justifications for information disclosure including the right to make an informed choice, the need to secure consumer trust, the avoidance of market failure and the right to know. But these are difficult and contested concepts. The current debate concerning EU requirements for the labelling of Genetically Modified products provides a compelling example of different models at play, which can as a result cause confusion and dissatisfaction amongst different interest groups. Much greater clarification of the justifications for information disclosure is required if their effectiveness as a technique for controlling trade product risks is to be properly assessed.

End-to-side nerve graft repair based on synergistic peripheral terminal motor branches: investigation in a nonhuman primate model

BACKGROUND: Spinal nerve avulsion frequently occurs in brachial plexus injury, becoming irreparable lesions. Nerve transfer at the very proximal site within a limited time interval after injury leads to satisfactory functional results. Oberlin reported a neurotization technique at a more peripheral location. Hypothetically, there might be useful functional results performing very peripheral end-to-side nerve graft repair using synergistic tiny terminal motor branches. We created one possible application of such a peripheral synergistic terminal end-to-side nerve transfer in a median nerve defect model in nonhuman primates. An end-to-side nerve graft repair bridging from the terminal motor branch of deep branch of the ulnar nerve to the thenar motor branch of median nerve was performed. The purpose of this study was to investigate the efficacy of this hypothesis. METHODS: Seven adult baboons were used in this study. At baseline, we electrophysiologically demonstrated no variation in innervation of median- and ulnar-nerve-innervated thenar muscles. Transection of the median nerve was performed. Subsequently, the abductor pollicis brevis muscle could neither be stimulated by the median nerve nor by the ulnar nerve. Baboons underwent end-to-side coaptation of a nerve graft to the deep branch of the ulnar nerve and end-to-end coaptation to the thenar motor branch of the median nerve. Assessment of functional recovery was performed by electrophysiological evaluation, thenar muscle weight, and video slow-motion analysis. RESULTS: All animals recovered opposition of the thumb 3 months after surgery. The abductor pollicis brevis muscle, preoperatively innervated by the median nerve, did not respond to electrophysiological stimulation of the transected median nerve but to stimulation of the ulnar nerve via the nerve graft. Length of nerve graft (in average 2.3 cm) showed no correlation to muscle weight or electrophysiological parameters. CONCLUSIONS: The results in this series demonstrate the efficacy of end-to-side nerve graft repair at the level of tiny very peripheral terminal motor branches in a nonhuman primate median nerve defect model. Applications of this technique may enhance functional results by avoidance of time-dependent end organ failure.

Success in crown and bridge work.

All practitioners wish for success in their restorative work mainly due to their desire to do the best for their patients, but increasingly the achievement of success, ie the avoidance of failure, is felt to be necessary to avoid the spectre of litigation. The number of patient-led litigation cases is on the increase and the majority involve crown and bridge work.