Remarks on the realization of the Atiyah-Singer index theorem in lattice gauge theory

We discuss the interplay between topologically non-trivial gauge field configurations and the spectrum of the Wilson-Dirac operator in lattice gauge theory. Our analysis is based on analytic arguments and numerical results from a lattice simulation of QED_2.Comment: Talk given at LATTICE97, 3 pages, 1 figur

Injury and illness profiles during the 2014 South African Ironman triathlon

Background: There is a need for ongoing scrutiny of injury and illness profiles of ultra-distance athletes. This study aimed to record the medical history, illness and injuries of athletes receiving medical attention during the 2014 Ironman South Africa (IMSA) triathlon, and to investigate the temporal presentation of medical encounters.Methods: This was a retrospective, cross-sectional study. All athletes who required medical attention at the main medical tent and all of the medical posts or mobile units along the route were included in this study A total of 2 331 athletes started the race. Data included age, gender, time and stage of the race when medical attention was required, pre-race medical history and medication use, illness and injuries treated, special investigations performed, and weather conditions.Results: Overall, 179 athletes (7.7%) required medical attention. The incidence of medical encounters was 7.8%. A significantly higher percentage of younger participants encountered medical problems (P = 0.04). Most patient encounters (80.1%) occurred after the race. The median duration of treatment was 26 minutes. Medication was used by 35.1% of patients during the race. The most common medical encounters were exertion-related (71.2%), gastro-intestinal (16.4%), dermatological (11.9%), musculoskeletal (9.6%) and cardiorespiratory conditions (2.4%).Conclusion: Medical encounters occurred more frequently in later stages of the race. Most medical conditions were exertion-related. Potential higher risk may be associated with medication use, recent illness, and in younger participants. Temporal stacking of medical personnel, planning of resources according to expected conditions, preventative measures for high-risk behaviour, and on-going data collection with comparable methodology are recommended.Keywords: triathletes, medical encounters, medication use, treatment, event medical managemen

Transplantation for diabetic nephropathy at Groote Schuur Hospital

Over a period of 6 years, 9 patients with diabetic nephropathy received renal allografts at Groote Schuur Hospital. This low figure represents 2,8% of the total number of renal transplants done at our institution, and is evidence of concern about the apparent poor results of transplantation in these patients. After 2 years, patients and graft survival rates in diabetics were 87% and 62% respectively. Vascular disease was a major problem. Six patients developed limb gangrene, and symptomatic coronary and cerebrovascular disease developed in 2 patients. Infections were common and included wound sepsis, cellulitis, candidiasis and urinary tract infections. Diabetes was poorly controlled after transplantation in 5 patients. Proliferative retinopathy was present in 6 patients but remained stable after transplantation.Despite very strict selection criteria, the results of renal transplantation in diabetic patients remain poor. Better treatment strategies are needed to justify acceptance of these patients for transplantation

Comparing the measurement of different social networks

__Background:__ Technological progress has enabled researchers to use new unobtrusive measures of relationships between actors in social network analysis. However, research on how these unobtrusive measures of peer connections relate to traditional sociometric nominations in adolescents is scarce. Therefore, the current study compared traditional peer nominated networks with more unobtrusive measures of peer connections: Communication networks that consist of instant messages in an online social platform and proximity networks based on smartphones' Bluetooth signals that measure peer proximity. The three social network types were compared in their coverage, stability, overlap, and the extent to which the networks exhibit the often observed sex segregation in adolescent social networks. __Method:__ Two samples were derived from the MyMovez project: a longitudinal sample of 444 adolescents who participated in the first three waves of the first year of the project (Y1; 51% male; Mage = 11.29, SDage = 1.26) and a cross-sectional sample of 774 adolescents that participated in fifth wave in the third year (Y3; 48% male; Mage = 10.76, SDage = 1.23). In the project, all participants received a research smartphone and a wrist-worn accelerometer. On the research smartphone, participants received daily questionnaires such as peer nomination questions (i.e., nominated networ

Phased-array wavelength demultiplexer with flattened wavelength response

A four-channel phased-array wavelength demultiplexer with a flattened wavelength response has been realised for the first time in InP/InGaAsP at 1.54 mu m by employing multimode output waveguides. The device has 2 nm channel spacing and a flat response (within 1 dB) of 17 n

The Impact of Social Media Influencers on Children’s Dietary Behaviors

Over the past years vlogs rapidly have become an attractive platform for food industries, sponsoring social media influencers to promote their products. As with more traditional media, social media influencers predominantly promote unhealthy drinks and foods that are high in sugar, fat, and salt – consumption of which may increase the risk of overweight, obesity, and non-communicable diseases. The aim of the current Brief Research Report is to examine the impact of vlogs on children’s unhealthy dietary behaviors. Drawing on longitudinal survey data from 453 8- to 12-year-old children, we analyzed the longitudinal relations between children’s frequency of watching vlogs and their consumption of unhealthy beverages and snacks. Structural path modeling analyses of three waves of data with 1-year intervals showed that children’s self-reported frequency of watching vlogs influenced consumption of unhealthy beverages 2 years later. The analyses did not yield significant relat

Proposal for Topologically Unquenched QCD

A proposal is presented for simulating an improvement on quenched QCD with dynamical fermions which interact with the gluon configuration only via the topological index of the latter. Strengths and shortcomings of the method are discussed and it is argued that the approximation - though being crude - shares some qualitative aspects of full QCD which relate to the issue of chiral symmetry breaking.Comment: latex, 13pp, material rearranged and better focused, final version to appear in Phys. Rev.

Testing a Social Network Intervention Using Vlogs to Promote Physical Activity Among Adolescents: A Randomized Controlled Trial

There is a need to stimulate physical activity among adolescents, but unfortunately, they are hard to reach with traditional mass media interventions. A promising alternative is to carry out social network interventions. In social network interventions, a small group of individuals (influence agents) is selected to promote health-related behaviors within their social network. This study investigates whether a social network intervention is more effective to promote physical activity, compared to a mass media intervention and no intervention. Ad

Peptidomics of a single identified neuron reveals diversity of multiple neuropeptides with convergent actions on cellular excitability

In contrast to classical transmitters, the detailed structures and cellular and synaptic actions of neuropeptides are less well described. Peptide mass profiling of single identified neurons of the mollusc Lymnaea stagnalis indicated the presence of 17 abundant neuropeptides in the cardiorespiratory neuron, visceral dorsal 1 (VD1), and a subset of 14 peptides in its electrically coupled counterpart, right parietal dorsal 2. Altogether, based on this and previous work, we showed that the high number of peptides arises from the expression and processing of four distinct peptide precursor proteins, including a novel one. Second, we established a variety of posttranslational modifications of the generated peptides, including phosphorylation, disulphide linkage, glycosylation, hydroxylation, N-terminal pyro-glutamylation, and C-terminal amidation. Specific synapses between VD1 and its muscle targets were formed, and their synaptic physiology was investigated. Whole-cell voltage-clamp analysis of dissociated heart muscle cells revealed, as tested for a selection of representative family members and their modifications, that the peptides of VD1 exhibit convergent activation of a high-voltage-activated Ca current. Moreover, the differentially glycosylated and hydroxylated α2 peptides were more potent than the unmodified α2 peptide in enhancing these currents. Together, this study is the first to demonstrate that single neurons exhibit such a complex pattern of peptide gene expression, precursor processing, and differential peptide modifications along with a remarkable degree of convergence of neuromodulatory actions. This study thus underscores the importance of a detailed mass spectrometric analysis of neuronal peptide content and peptide modifications related to neuromodulatory function. Copyright © 2006 Society for Neuroscience

Surgical treatment for squamous cell carcinoma of the temporal bone: predictors of survival

Objective. Evaluation of the management and survival in patients treated for temporal bone squamous cell carcinoma (TBSCC) in a tertiary referral centre.Methods. Forty-nine patients underwent primary treatment for TBSCC. Thirty-six patients underwent a lateral temporal bone resection (LTBR) or subtotal temporal bone resection (STBR). Overall survival (OS) and disease-specific survival (DSS) analysis were assessed.Results. Five-year OS of the 49 patients was 39%. Five-year OS of the 36 patients who underwent LTBR or STBR was 46%. Tumour-free margins were achieved in all patients with T1 and T2 disease, in 59% patients with T3 tumours and 0% patients with T4 disease. Fiveyear DSS was 85% for all T1/T2 tumours, 53% for T3 tumours and 0% for T4 tumours. Clear resection margins was the only significant predictor of DSS in our cohort.Conclusions. The mainstay of treatment for TBSCC is temporal bone resection with tumour free resection margins, with or without adjuvant radiotherapy. Survival is negatively influenced by non-radical resection. T1 and T2 tumours can be managed safely with LTBR. More advanced disease requires a more extensive resection, with a higher likelihood of nonradical resections and decreased survival rates.Otorhinolaryngolog