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In the post-Apartheid era South Africa's universities have faced serious questions about the quality of their student learning in the face of near impossible challenges. The University of Cape Town, widely seen as the country's leading higher education institution, has shown remarkable resilience, however, in the range of initiatives it has launched to support and enhance student learning. These initiatives, designed with a common purpose, are of course intended to work together so that their effects might be compounded and realized in enhanced student learning outcomes. Drawing substantially on the power of compounding (which is itself redolent of the claim made by complexity theory that relations and emergence are crucial concepts), complexity theory offers unique insights into how and why things change – and also into how and why things remain largely the same or inexorably grind towards failure. The networked initiatives undertaken by the University of Cape Town constitute a case of learning refurbishment that is also well explained and understood in terms of complexity theory. This paper draws on concepts from complexity theory both to understand how learning might be enhanced in higher education institutions in severely straitened circumstances and to offer insights for education leaders and policy-makers in this domain. [ABSTRACT FROM AUTHOR]

Aims For bradycardic patients after cardiac surgery, it is unknown how long to wait before implanting a permanent pacemaker (PPM). Current recommendations vary and are based on observational studies. This study aims to examine why this variation may exist. Methods and results We conducted first a study of patients in our institution and second a systematic review of studies examining conduction disturbance and pacing after cardiac surgery. Of 5849 operations over a 6-year period, 103 (1.8%) patients required PPM implantation. Only pacing dependence at implant and time from surgery to implant were associated with 30-day pacing dependence. The only predictor of regression of pacing dependence was time from surgery to implant. We then applied the conventional procedure of receiver operating characteristic (ROC) analysis, seeking an optimal time point for decision-making. This suggested the optimal waiting time was 12.5 days for predicting pacing dependence at 30 days for all patients (area under the ROC curve (AUC) 0.620, P = 0.031) and for predicting regression of pacing dependence in patients who were pacing-dependent at implant (AUC 0.769, P < 0.001). However, our systematic review showed that recommended optimal decision-making time points were strongly correlated with the average implant time point of those individual studies (R = 0.96, P < 0.001). We further conducted modelling which revealed that in any such study, the ROC method is strongly biased to indicate a value near to the median time to implant as optimal. Conclusion When commonly used automated statistical methods are applied to observational data with the aim of defining the optimal time to pacing after cardiac surgery, the suggested answer is likely to be similar to the average time to pacing in that cohort. [ABSTRACT FROM AUTHOR]

Introduction: It is not known whether the optimal atrioventricular (AVopt) delay varies between left ventricular (LV) pacing site during endocardial biventricular pacing (BiVP) and may therefore needs consideration. Methods: We assessed the hemodynamic AVopt in patients with chronic heart failure undergoing endocardial LV lead implantation. AVopt was assessed during atrio‐BiVP with a "roving LV lead." Up to four locations were studied: mid‐lateral wall, mid‐septum (or a close alternative), site of greatest hemodynamic improvement, and LV lead implant site. The AVopt was compared to a fixed AV delay of 180 ms. Results: Seventeen patients were included (12 male, aged 66.5 ± 12.8 years, ejection fraction 26 ± 7%, 16 left bundle branch block or high percentage of right ventricular pacing [RVP], QRS duration 167 ± 27 ms). In most locations (62/63), AVopt increased systolic blood pressure during BiVP compared with RVP (relative improvement 6 mmHg, interquartile range [IQR] 4–9 mmHg). Compared to a fixed AV delay, the hemodynamic improvement at AVopt was higher (1 mmHg, IQR 0.2–2.6 mmHg, p <.001). Within most patients (16/17), we observed a difference in AVopt between pacing sites (median paced AVopt 209 ms, IQR 117–250). Within this range, the hemodynamic impact of these differences was small (median loss 0.6 mmHg, IQR 0.1–2.6 mmHg). Conclusion: Within a patient, different endocardial LV lead locations have slightly different hemodynamic AVopt which are superior to a fixed AV delay. The hemodynamic consequence of applying an optimum from a different lead location is small. [ABSTRACT FROM AUTHOR]

This retrospective cohort study analyzed the short-term outcomes of patients undergoing total knee arthroplasty receiving periarticular anesthetic injections (PAIs) with and without continuous adductor canal blocks (CACBs) regarding early postoperative narcotic use, pain scores, and range of motion with otherwise similar postoperative regimens. Two hundred ninety-four patients were included: 120 received PAIs with CACBs, and 174 received PAIs only. Matched analysis was performed for type of anesthesia. There were substantial decreases in early inpatient narcotic use with the addition of CACBs to PAIs with general and spinal anesthesia without an adverse effect on pain, knee range of motion, or length of stay. [Orthopedics. 2023;46(3):185–191.] [ABSTRACT FROM AUTHOR]

The article discusses the U.S. could witness further consolidation of populist authoritarianism, declining standards of civility, and perhaps also US withdrawing further from the global institutions that it had itself played a steering role in establishing. Or else Americans could demand a return to the political values to which it has long aspired and promoted around the world, even if it has seldom realized them.

Global flows of international students have diversified in recent years. As a result, the common association of this form of mobility with affluent members of the global middle class increasingly does not hold. This study focuses on one emergent student migration pattern that has been the subject of relatively little empirical research: that of African international students in China. The main aim is to establish how international student migration is experienced differentially by students positioned in their home societies in unequal ways, thereby moving beyond the notion that international student migration is a middle-class activity. Drawing on data from semi-structured interviews with 40 students from 14 African countries, we apply Bourdieu’s theory of practice to examine the extent and nature of habitus transformation of students from a variety of social backgrounds. We show that differences in social background in this particular case led to distinct trajectories during the sojourn and in terms of post-study plans. Our study makes a theoretical contribution to the international student migration literature, arguing that the nature of transformation that took place among student migrants as a result of study was shaped by the nature of mobility, both spatial and social. [ABSTRACT FROM AUTHOR]

Although mechanical stress in total hip arthroplasty modular head-neck junctions is thought to contribute to the risk of trunnionosis and related metal ion disease in total hip arthroplasty, little is known about mechanical stress in the modular acetabular components. Recent retrieval analyses of dual-mobility constructs have demonstrated corrosion between liner and shell in some dual-mobility acetabular components. The objective of this study was to evaluate acetabular stress as a function of acetabular bone coverage, component modularity, and femoral head diameter. A parametric finite element model was created. The acetabulum was set at 40° of abduction and 15° of anteversion; superolateral bone loss up to 50° was modeled; and 28-mm, 32-mm, 36-mm, and 40-mm head sizes were simulated in stance phase of gait. Fixed polyethylene-bearing, monoblock and modular dual-mobility (MDM) acetabular components were evaluated. For traditional fixed-bearing components, the largest peak stress, 49.5 MPa, was observed with 50° of bone loss and a 28-mm head. The lowest peak stress, 6.3 MPa, occurred with complete bone coverage and a 36-mm head. Peak stress in the MDM construct, 25.1 MPa, concentrated in the chromium-cobalt portion of the construct. Larger head diameters are associated with decreased stress in the acetabular component when bone loss is present. An MDM construct with a stiff inner liner may decrease overall stress in the acetabular construct, but focally increased stress near the rim of uncovered acetabular components may increase the risk of metal-on-metal corrosion. [Orthopedics. 2021;44(5):280-284.]. [ABSTRACT FROM AUTHOR]

All herpesviruses encode a conserved DNA polymerase that is required for viral genome replication and serves as an important therapeutic target. Currently available herpesvirus therapies include nucleoside and non-nucleoside inhibitors (NNI) that target the DNA-bound state of herpesvirus polymerase and block replication. Here we report the ternary complex crystal structure of Herpes Simplex Virus 1 DNA polymerase bound to DNA and a 4-oxo-dihydroquinoline NNI, PNU-183792 (PNU), at 3.5 Å resolution. PNU bound at the polymerase active site, displacing the template strand and inducing a conformational shift of the fingers domain into an open state. These results demonstrate that PNU inhibits replication by blocking association of dNTP and stalling the enzyme in a catalytically incompetent conformation, ultimately acting as a nucleotide competing inhibitor (NCI). Sequence conservation of the NCI binding pocket further explains broad-spectrum activity while a direct interaction between PNU and residue V823 rationalizes why mutations at this position result in loss of inhibition. Various herpesvirus therapeutics target the viral DNA polymerase. Here, the authors present the crystal structure of herpesvirus polymerase in the elongating state with bound primer-template DNA and the broad-spectrum non-nucleoside inhibitor PNU-183792, which is of interest for further drug design. [ABSTRACT FROM AUTHOR]

Open in new tab Download slide Open in new tab Download slide OBJECTIVES The intermediate-term all-cause mortality rate of real-world patients with multivessel disease (MVD) treated with percutaneous coronary intervention (PCI) with new-generation drug-eluting stents or coronary artery bypass grafting (CABG) remains unknown. We sought to compare the intermediate-term all-cause mortality rates of real-world patients with MVD including left main stem disease, treated with CABG or PCI. METHODS All consecutive all-comer patients with MVD undergoing CABG or PCI with second/third generation drug-eluting stents from 2007 to 2015 in Harefield Hospital, UK were included in this study. The revascularization modality was based on heart team discussions. Primary outcome was all-cause mortality. Mean follow-up of the study was 3.3 years. Cox regression analysis and propensity matching were used. RESULTS Of 6383 patients with MVD, 4230 underwent CABG, whereas 2153 had PCI with new-generation stents. In the CABG group, the mean age was 66.4 ± 10 years, whereas in the PCI group it was 65.3 ± 12.1 years (P  < 0.001). Fewer female patients with MVD were treated with CABG than were treated with PCI (18.5% vs 20.5%; P  = 0.026). There was a higher 5-year estimated survival rate among patients having CABG (88% vs 78.3%; P log-rank < 0.001). The adjusted hazard ratio (HR) for PCI over CABG was 1.74 [95% confidence interval (CI) 1.41–2.16; P  < 0.001]. A total of 653 patients having CABG and 653 having PCI were included in the propensity-matched groups. At mean follow-up, PCI was associated with a higher adjusted HR for all-cause mortality (2.18, 95% CI 1.54–3.1; P  < 0.001). CONCLUSIONS In this contemporary cohort of real-world patients with MVD, CABG was associated with increased intermediate-term survival compared to PCI with new-generation drug-eluting stents. [ABSTRACT FROM AUTHOR]

We defend in this paper the importance of redistributing power in the field of education development by enhancing the self-sustainability of education initiatives and minimizing their roots in dependency – these as pre-requisites for improving their sustainable development outcomes. We do this by considering an education development initiative run by the Barefoot College in India, and then developing an explanatory model based in complexity theory (as expounded by Edgar Morin) and in the capability approach (as developed principally by Amartya Sen and Martha Nussbaum). We conclude that such a redistribution of power would help to ensure that education is better connected to its development context, more relevant to the interests and needs of the community it serves, and its quality enhanced. More generally, we reinforce existing arguments – but from the perspective and imperative of sustainability – why it is in the interests of policy-makers to devolve power and to provide resources to such initiatives. Doing so would enhance governments' prospects of realizing their education and social development goals. The arrogation of power and resources towards the centre, an almost natural impulse in policy-making, is, in the end, counter-productive, and threatens sustainable education and social development. [ABSTRACT FROM AUTHOR]

Background: Patients often are asked to report walking distances before joint arthroplasty and when discussing their results after surgery, but little evidence demonstrates whether patient responses accurately represent their activity.Questions/purposes: Are patients accurate in reporting distance walked, when compared with distance measured by an accelerometer, within a 50% margin of error?Methods: Patients undergoing THA or TKA were recruited over a 16-month period. One hundred twenty-one patients were screened and 66 patients (55%) were enrolled. There were no differences in mean age (p = 0.68), proportion of hips versus knees (p = 0.95), or sex (p = 0.16) between screened and enrolled patients. Each patient wore a FitBit Zip accelerometer for 1 week and was blinded to its measurements. The patients reported their perceived walking distance in miles daily. Data were collected preoperatively and 6 to 8 weeks postoperatively. Responses were normalized against the accelerometer distances and Wilcoxon one-tailed signed-rank testing was performed to compare the mean patient error with a 50% margin of error, our primary endpoint.Results: We found that patients' self-reported walking distances were not accurate. The mean error of reporting was > 50% both preoperatively (p = 0.002) and postoperatively (p < 0.001). The mean magnitude of error was 69% (SD 58%) preoperatively and 93% (SD 86%) postoperatively and increased with time (p = 0.001).Conclusions: Patients' estimates of daily walking distances differed substantially from those patients' walking distances as recorded by an accelerometer, the accuracy of which has been validated in treadmill tests. Providers should exercise caution when interpreting patient-reported activity levels.Level Of Evidence: Level III, diagnostic study. [ABSTRACT FROM AUTHOR]

This naturalistic study was designed to examine the effectiveness of a 4-week skill-based group therapy that focuses on building resilience. The group, informed by Dialectical Behavior Therapy (DBT; Linehan, 1993, 2015), targets general clients at college counseling centers and emphasizes mindfulness as a coping strategy to stress, cognitive rigidity, emotion dysregulation, and interpersonal difficulties. Results indicated that group members showed clinically significant improvement in psychological resilience and general mental health at the conclusion of group therapy. Implications are discussed. [ABSTRACT FROM AUTHOR]

A retrospective study was completed to assess the success rate of endosseous cylinder implants placed in mandibles that were 10 mm or less in maximum anterior height as measured from lateral cephalometric radiographs. Only implants that were located anteriorly between the mental foramina and loaded prosthetically for a minimum of 1 year were studied. Twenty-eight patients with a total of 130 Nobelpharma implants (forty-six 7 mm and eighty-four 10 mm) were included. The fixtures were evaluated following standard clinical criteria for success established for implants of this type. A total of 8 (two 7 mm and six 10 mm) of 130 implants failed, yielding an overall success rate of 94%. Major complications encountered included a complete mandibular fracture, a partial mandibular fracture, and a temporary bilateral mental nerve hypoesthesia. [ABSTRACT FROM AUTHOR]

The article looks at U.S. Foreign Direct Investment (FDI) in Japan. Although increased FDI in Japan would allow U.S. companies to sell their products there more successfully and allow them to closely monitor their Japanese competitors, the level of U.S. investment in Japan remains minimal. The author compares the FDI stocks in Japan by the U.S. to those of other countries such as Germany and France. The top 25 foreign-affiliated companies in Japan are listed. The author discusses impediments keeping the U.S. from placing greater direct investments in Japan, noting several host country factors. The main Japanese preventative measure against greater FDI inflow comes from the private sector rather than the public sector. Toys 'R' Us and Merck & Company are given as examples of FDI.

Background: Studies comparing coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI) have largely been performed in the bare-metal stent (BMS) and first-generation drug eluting stent (F-DES) era. Second-generation DES (S-DES) have shown improved outcomes when compared to F-DES, but data comparing CABG with PCI using S-DES is limited. We compared mortality following CABG versus PCI for patients with multivessel disease and analyzed different stent types. Methods: A total of 6,682 patients underwent multivessel revascularization at Harefield Hospital, UK. We stratified CABG patients into single arterial graft (SAG) or multiple arterial grafts (MAG); and PCI patients into BMS, F-DES or S-DES groups. We analyzed all-cause mortality at 5 years. Results: 4,388 patients had CABG (n[SAG] = 3,358; n[MAG] = 1,030) and 2,294 patients had PCI (n[BMS] = 416; n[F-DES] = 752; n[S-DES] = 1,126). PCI had higher 5-year mortality with BMS (HR = 2.27, 95% CI:1.70–3.05, p<0.001); F-DES (HR = 1.52, 95% CI:1.14–2.01, p = 0.003); and S-DES (HR = 1.84, 95% CI:1.42–2.38, p<0.001). This was confirmed in inverse probability treatment weighted analyses. When adjusting for both measured and unmeasured factors using instrumental variable analyses, PCI had higher 5-year mortality with BMS (Δ = 15.5, 95% CI:3.6,27.5, p = 0.011) and FDES (Δ = 16.5, 95% CI:6.6,26.4, p<0.001), but had comparable mortality with CABG for PCI with SDES (Δ = 0.9, 95% CI: -9.6,7.9, p = 0.844), and when exclusively compared to CABG patients with SAG (Δ = 0.4, 95% CI: -8.0,8.7, p = 0.931) or MAG (Δ = 4.6, 95% CI: -0.4,9.6, p = 0.931). Conclusions: In this real-world analysis, when adjusting for measured and unmeasured confounding, PCI with SDES had comparable 5-year mortality when compared to CABG. This warrants evaluation in adequately-powered randomized controlled trials. [ABSTRACT FROM AUTHOR]

Advances in left ventricular assist device (LVAD) therapy have resulted in increasing numbers of adult LVAD recipients in the community. However, device failure, stroke, bleeding, LVAD thrombosis and systemic infection can be life-threatening emergencies. Currently, four LVAD systems are implanted in six UK transplant centres, each of which provides device-specific information to local emergency services. This has resulted in inconsistent availability and content of information with the risks of delayed or inappropriate decision-making. In order to improve patient safety, a consortium of UK healthcare professionals with expertise in LVADs developed universally applicable prehospital emergency algorithms. Guidance was framed as closely as possible on the standard ABCDE approach to the assessment of critically ill patients. [ABSTRACT FROM AUTHOR]

Aims: Cardiac resynchronization therapy (CRT) may exert its beneficial haemodynamic effect by improving ventricular synchrony and improving atrioventricular (AV) timing. The aim of this study was to establish the relative importance of the mechanisms through which CRT improves cardiac function and explore the potential for additional improvements with improved ventricular resynchronization.Methods and Results: We performed simulations using the CircAdapt haemodynamic model and performed haemodynamic measurements while adjusting AV delay, at low and high heart rates, in 87 patients with CRT devices. We assessed QRS duration, presence of fusion, and haemodynamic response. The simulations suggest that intrinsic PR interval and the magnitude of reduction in ventricular activation determine the relative importance of the mechanisms of benefit. For example, if PR interval is 201 ms and LV activation time is reduced by 25 ms (typical for current CRT methods), then AV delay optimization is responsible for 69% of overall improvement. Reducing LV activation time by an additional 25 ms produced an additional 2.6 mmHg increase in blood pressure (30% of effect size observed with current CRT). In the clinical population, ventricular fusion significantly shortened QRS duration (Δ-27 ± 23 ms, P < 0.001) and improved systolic blood pressure (mean 2.5 mmHg increase). Ventricular fusion was present in 69% of patients, yet in 40% of patients with fusion, shortening AV delay (to a delay where fusion was not present) produced the optimal haemodynamic response.Conclusions: Improving LV preloading by shortening AV delay is an important mechanism through which cardiac function is improved with CRT. There is substantial scope for further improvement if methods for delivering more efficient ventricular resynchronization can be developed.Clinical Trial Registration: Our clinical data were obtained from a subpopulation of the British Randomised Controlled Trial of AV and VV Optimisation (BRAVO), which is a registered clinical trial with unique identifier: NCT01258829, https://clinicaltrials.gov. [ABSTRACT FROM AUTHOR]

Objective: Unusual clinical course Background: Acute compartment syndrome (ACS) of the thigh after elective primary total knee arthroplasty is rare. If not recognized and treated promptly, devastating consequences may result. Certain regional anesthesia techniques are thought to mask the symptoms of acute compartment syndrome, but there are no cases reported of adductor canal catheters masking the symptoms of thigh compartment syndrome. We report a case where symptoms and diagnosis of acute anterior thigh compartment syndrome were not masked by a functioning adductor canal catheter. Case Report: A 56-year-old male developed anterior thigh compartment syndrome after an elective primary total knee arthroplasty. Surgery was performed under spinal anesthesia with periarticular local infiltration analgesia. Postoperatively, an adductor canal catheter was placed, atraumatically, under ultrasound guidance in the recovery room with a plan to begin a continuous infusion of 0.2% ropivacaine 10 hours after the periarticular injection. Six hours after surgery, the patient complained of tightness and 10/10 pain in his right thigh, which was initially managed with parenteral opioids with moderate success. Continuous infusion through the adductor canal catheter was started and pain improved to 6/10 aching pain. Nonetheless, two hours after starting the continuous infusion, the patient reported tightness, swelling, and 10/10 pressure-like pain that was not relieved by the peripheral catheter infusion or PRN boluses of additional opioids. Due to the patient's symptomatology compartment pressures were measured. The anterior compartment pressure was 47 mm Hg and emergent anterior compartment fasciotomy was performed. Conclusions: In this case, a functioning adductor canal catheter did not mask symptoms of, or delay diagnosis of, acute compartment syndrome in the thigh. [ABSTRACT FROM AUTHOR]

The article discusses the possibility of implementing policy change in education using the complexity theory. Topics include the complexity of the decentralisation of the education systems due to the dynamic open systems, the implementation and sustainability of policy change in education governance, and the role of status quo in the resistance to change.

A number of issues can affect sample size in qualitative research; however, the guiding principle should be the concept of saturation. This has been explored in detail by a number of authors but is still hotly debated, and some say little understood. A sample of PhD studies using qualitative approaches, and qualitative interviews as the method of data collection was taken from theses.com and contents analysed for their sample sizes. Five hundred and sixty studies were identified that fitted the inclusion criteria. Results showed that the mean sample size was 31; however, the distribution was non-random, with a statistically significant proportion of studies, presenting sample sizes that were multiples of ten. These results are discussed in relation to saturation. They suggest a pre-meditated approach that is not wholly congruent with the principles of qualitative research. [ABSTRACT FROM AUTHOR]

Aluminum halide, alkoxide and amide complexes 2–6 of the form (N,N)AlX2−nYn (n = 0, 1 and (N,N) = 1,9-dimesityl-5-phenyldipyrromethene (1)) were synthesized and characterized by NMR spectroscopy and X-ray crystallography. The in situ generated lithium salt of dipyrromethene 1 was reacted with AlX3 to afford aluminum halide complexes (N,N)AlX2 (X = Cl (2), I (3)) which were isolated as dichroic crystals. Salt metathesis reactions were employed to produce alkoxide complexes (N,N)Al(Cl)(OtBu) (4) and (N,N)Al(OtBu)2 (5) from compound 2. The dimethylamide complex (N,N)Al(NMe2)2 (6) was prepared by reaction of dipyrromethene 1 with [Al(NMe2)3]2. Crystallographic data revealed that the dipyrromethene is non-planar when bulky coligands are present as in compounds 3–6, while in the dichloride complex 2 the dipyrromethene is planar. Halide complexes 2 and 3 reacted with adventitious moisture in toluene to afford crystalline acid–base adducts (N,N)H·HX, (X = Cl (7), I (8)), which adopted structures reminiscent of anion receptors. Alkoxide and dimethylamide complexes 5 and 6 were also applied as precatalysts for the ring-opening polymerization of ε-caprolactone and preliminary results are reported. [ABSTRACT FROM AUTHOR]

Background. Biomarkers used at the time of diagnosis to tailor treatment decisions may diffuse into clinical practice before data become available on whether biomarker testing reduces cancer mortality. In the interim, quantitative estimates of the mortality impact of testing are needed to assess the value of these diagnostic biomarkers. These estimates are typically generated by customized models that are resource intensive to build and apply. Methods. We developed a user-friendly system of models for Cancer Translation of Comparative Effectiveness Research (CANTRANce) to model the mortality impact of cancer interventions. The Diagnostic Biomarker module of this system projects the mortality impact of testing for a diagnostic biomarker, given data on how testing affects treatment recommendations. Costs and quality-of-life outcomes may also be modeled. We applied the Diagnostic Biomarker module to 2 case studies to demonstrate its capabilities. Results. The user interface (http://www.fhcrc.org/cantrance) allows comparative effectiveness researchers to use the Diagnostic Biomarker module of CANTRANce. Our case studies indicate that the model produces estimates on par with those generated by customized models and is a strong tool for quickly generating novel projections. Limitations. The simple structure that makes CANTRANce user-friendly also constrains the complexity with which cancer progression can be modeled. The quality of the results rests on the quality of the input data, which may pertain to small or dissimilar populations or suffer from informative censoring. Conclusions. The Diagnostic Biomarker module of CANTRANce is a novel public resource that can provide timely insights into the expected mortality impact of testing for diagnostic biomarkers. The model projections should be useful for understanding the long-term potential of emerging diagnostic biomarkers. [ABSTRACT FROM AUTHOR]

The updated United Kingdom Anti-Drugs strategy highlights gaps in the current body of drug related knowledge. Although work has been addressing these gaps for a number of years now, it has proven challenging to establish the dynamics of emerging drug tendencies within local areas. Some work of this nature has been carried out within the UK, but these studies have been beset by problems. With this in mind the Drugs Analysis and Research Programme and Market and Opinion Research International (MORI) embarked on developmental work to assess whether a national project, involving progressive sweeps of interviews with key professionals and drug users, in ten areas of England and Wales, would help fill these gaps still further. Findings suggested that the overall process worked very well. Not only did the project prove feasible, but interviews were felt to have produced real time, policy relevant information. However, it was felt that the project was often resource hungry. [ABSTRACT FROM AUTHOR]

Examines the role of teachers with respect to knowledge, an issue that has been reopened as a consequence of the widespread interest in outcomes-based education. Proponents of an outcomes-based education; Notion of teachers as mediators of knowledge; Teachers as socio-cultural critics.

Leucine is an essential branched-chain amino acid that acts as a substrate for protein synthesis and as a signaling molecule. Leucine not incorporated into muscle protein is ultimately oxidized through intermediates such as β-hydroxy-β-methylbutyrate (HMB) which itself is reported to enhance muscle mass and function in rats and humans. HMB has been reported in the plasma following oral leucine administration in sheep and pigs but not in Sprague-Dawley rats, the standard preclinical model. Therefore, we conducted radiolabeled absorption, distribution, metabolism and excretion (ADME) studies in rats using a low (3 mg/kg) or high dose (1,000 mg/kg) of C-leucine. Blood, tissue, and urine samples were analyzed for C-leucine and its metabolites by HPLC-MS. Our results show for the first time that C-HMB appears in plasma and urine of rats following an oral dose of C-leucine. C-leucine appears in plasma as C-α-ketoisocaproic acid (KIC) with a slower time course than C-HMB, a putative product of KIC. Further, two novel metabolites of leucine were detected in urine, N-acetyl leucine and glycyl leucine. Mass balance studies demonstrate that excretory routes accounted for no more than 0.9 % of the radiolabel and approximately 61 % of the dose was recovered in the carcass. Approximately 65 % of the dose was recovered in total, suggesting that approximately one-third of the leucine dose is oxidized to CO. In conclusion, this study demonstrates endogenous production of HMB from leucine in adult rats, a standard preclinical model used to guide design of clinical trials in nutrition. [ABSTRACT FROM AUTHOR]