A reduction theorem for tau -rigid modules

We prove a theorem which gives a bijection between the support τ -tilting modules over a given finite-dimensional algebra A and the support τ -tilting modules over A / I, where I is the ideal generated by the intersection of the center of A and the radical of A. This bijection is both explicit and well-behaved. We give various corollaries of this, with a particular focus on blocks of group rings of finite groups. In particular we show that there are τ -tilting-finite wild blocks with more than one simple module. We then go on to classify all support τ -tilting modules for all algebras of dihedral, semidihedral and quaternion type, as defined by Erdmann, which include all tame blocks of group rings. Note that since these algebras are symmetric, this is the same as classifying all basic two-term tilting complexes, and it turns out that a tame block has at most 32 different basic two-term tilting complexes. We do this by using the aforementioned reduction theorem, which reduces the problem to ten different algebras only depending on the ground field k, all of which happen to be string algebras. To deal with these ten algebras we give a combinatorial classification of all τ -rigid modules over (not necessarily symmetric) string algebras

Magneto-exciton in planar type II quantum dots

We study an exciton in a type II quantum dot, where the electron is confined in the dot, but the hole is located in the barrier material. The exciton properties are studied as a function of a perpendicular magnetic field using a Hartree-fock mesh calculation. Our model system consists of a planar quantum disk. Angular momentum (l) transitions are predicted with increasing magnetic field. We also study the transition from a type I to a type II quantum dot which is induced by changing the confinement potential of the hole. For sufficiently large magnetic fields a re-entrant behaviour is found from $l_{h}=0$ to $l_{h}\neq 0$ and back to $l_{h}=0$, which results in a transition from type II to type I.Comment: 6 pages, 12 figure

Measuring perceived black economic empowerment in the South African wine industry

The aim of this study is to develop a scale to measure perceived black economic empowerment (BEE) as reported by beneficiaries themselves. Two scale development procedures were carried out on randomly selected samples of 213 and 322 previously disadvantaged individual respondents within 14 and 11wine business that cover the larger part of the wine industry chain. The results led to a 'feeling' self-report scale (5-dimensions) and an ‘evolution’ self-report scale (6-dimensions). The emerged dimensions are: Business ownership and control (BOC), Access to finance (ATF), Employment and Human Resources Management (EMP) [internal and external], Social capital/enabling environment (SOC) and Lobbying power and collective action (LOB). First measurement results indicate that respondents feel less empowered with respect to BOC and ATF as compared to EMP, SOC and LOB. There appears to be no gender or age differences, but there are geographical differences. The latter is mostly per farm, that is, a lot of variation in BEE is observed at the firm level. The scale can be used at the firm and industry level as a diagnostic tool to monitor BEE progress as a complementary and not a substitutive framework to the wine industry scorecard as an objective measure of BEE. Future research should focus on the gap between the two definitions and assessment tools in order to comprehensively capture BEE in its entirety. The scale can also be adapted to fit the context, for example, its use in the agricultural sector at large.Agribusiness,

Pre- and post-testing counseling considerations for the provision of expanded carrier screening : exploration of European geneticists’ views

Background: Carrier screening is generally performed with the aim of identifying healthy couples at risk of having a child affected with a monogenic disorder to provide them with reproductive options. Expanded carrier screening (ECS), which provides the opportunity for multiple conditions to be screened in one test, offers a more cost-effective and comprehensive option than screening for single disorders. However, implementation of ECS at a population level would have implications for genetic counseling practice. Methods: We conducted semi-structured interviews with sixteen European clinical and molecular geneticists with expertise in carrier screening to explore their views on the implementation of ECS in the clinical setting. Results: Using inductive content analysis, we identified content categories relevant to the pre- and post-test settings. Participants believed ECS would ideally be targeted at couples before pregnancy. There was some disagreement regarding the acceptability of performing ECS in individuals, with several participants actively opposing individual-based screening. In addition, participants discussed the importance of ensuring informed and voluntary participation in ECS, recommending measures to minimize external pressure on prospective parents to undergo testing. A need for adequate counseling to foster informed, autonomous reproductive decision-making and provide support for couples found to be at risk was emphasized. Conclusions: Practical challenges in optimizing pre-test education and post-test counseling should not be underestimated and they should be carefully addressed before implementing ECS in the clinical setting

Decadal water balance of a temperate Scots pine forest (Pinus sylvestris L.) based on measurements and modelling

We examined the water balance components of an 80-year-old Scots pine (Pinus sylvestris L.) forest stand in the Campine region of Belgium over a ten year period using five very different approaches; our methods ranged from data intensive measurements to process model simulations. Specifically, we used the conservative ion method (CI), the Eddy Covariance technique (EC), an empirical model (WATBAL), and two process models that vary greatly in their temporal and spatial scaling, the ORCHIDEE global land-surface model and SECRETS a stand- to ecosystem-scale biogeochemical process model. Herein we used the EC technique as a standard for the evapotranspiration (ET) estimates. Using and evaluating process based models with data is extremely useful as models are the primary method for integration of small-scale, process level phenomena into comprehensive description of forest stand or ecosystem function. Results demonstrated that the two process models corresponded well to the seasonal patterns and yearly totals of ET from the EC approach. However, both WATBAL and CI approaches overestimated ET when compared to the EC estimates. We found significant relationships between several meteorological variables (i.e., vapour pressure deficit [VPD], mean air temperature [Tair], and global radiation [Rg]) and ET on monthly basis for all approaches. In contrast, few relationships were significant on annual basis. Independent of the method examined, ET exhibited low inter-annual variability. Consequently, drainage fluxes were highly correlated with annual precipitation for all approaches examined, except CI

Lifetime measurements of Triaxial Strongly Deformed bands in 163^{163}Tm

With the Doppler Shift Attenuation Method, quadrupole transition moments, $Q_t$, were determined for the two recently proposed Triaxial Strongly Deformed (TSD) bands in $^{163}$Tm. The measured $Q_t$ moments indicate that the deformation of these bands is larger than that of the yrast, signature partners. However, the measured values are smaller than those predicted by theory. This observation appears to be valid for TSD bands in several nuclei of the regionComment: 8 pages, 5 figures. Submitted to Physical Review