Generalizations of Nil Clean to Ideals

The notion of a clean ring has many variations that have been widely studied, including the sub-class of nil clean rings. We develop new variations of this concept and discuss the interactions between these new properties and those in the established canon. The first property we define is an ideal-theoretic generalization of the element-wise defined property nil clean, the condition that an element of a ring is the sum of a nilpotent and an idempotent. We establish a few characterizations for certain families of rings with this property, called ideally nil clean. In particular, a commutative ring is ideally nil clean if and only if it is strongly pi-regular. We show that the class of ideally nil clean rings also includes artinian rings, and von Neumann regular rings. Among other results, we demonstrate that ideally nil clean rings behave well under some ring extensions such as direct products and matrix rings. We also expand this generalization to the ideally nil clean property for one-sided ideals, and discuss the interaction between these different generalizations. We explore the interplay between nil clean rings and ideally nil clean rings

Pengaruh Brand Image Dan Product Design Terhadap Purchase Decision Dan Repurchase Intention Pada Produk Sepatu Futsal Merek Specs Di Kota Pekanbaru

This research is conducted to analyze the influence of Brand Image and Product design toward Purchase Decision and Repurchase Intention on customers of product futsal shoes brand Specs at Pekanbaru City . There are four latent variables in this research such as Brand Image (X1), Product Design (X1), Purchase Decision (Y1) and Repurchase Intention (Y2). The population of this study are all customers of product futsal shoes brand Specs at Pekanbaru City with a sample of 152 respondents were selected using accidental sampling method with criteria every player whose wear Specs futsal shoes at the fields. Data in this study are taken by giving them structural questionaires. Meanwhile, Path Analysis method are chosen for data analysis by SPSS version 21. The result of this research shows that Brand Image affect significantly towards Purchase Decision so the higher Brand Image is applied, the higher of Purchase Decision of Specs customers at Pekanbaru City, Product Design affect significantly towards Purchase Decision so the higher the Product Design then the higher Purchase Decision on Specs customers at Pekanbaru City, Brand Image affect significantly towards Repurchase Intention on Specs customers at Pekanbaru City. Product Design affect significantly towards Repurchase Intention on Specs Customers at Pekanbaru City. Purchase Decision proved to affect Repurchase Intention on Specs Customers at Pekanbaru City. Brand Image and Product Design affect significantly towards Repurchase Intention through Purchase Decision on Specs Customers at Pekanbaru City. Researchers suggest that Specs Company to keep and even improve the quality, realize the consumer desire and other factors that increase Purchase Decision dan Repurchase Intention customer

Understanding Treatment Refusal Among Adults Presenting for HIV-Testing in Soweto, South Africa: A Qualitative Study

HIV treatment initiatives have focused on increasing access to antiretroviral therapy (ART). There is growing evidence, however, that treatment availability alone is insufficient to stop the epidemic. In South Africa, only one third of individuals living with HIV are actually on treatment. Treatment refusal has been identified as a phenomenon among people who are asymptomatic, however, factors driving refusal remain poorly understood. We interviewed 50 purposively sampled participants who presented for voluntary counseling and testing in Soweto to elicit a broad range of detailed perspectives on ART refusal. We then integrated our core findings into an explanatory framework. Participants described feeling “too healthy” to start treatment, despite often having a diagnosis of AIDS. This subjective view of wellness was framed within the context of treatment being reserved for the sick. Taking ART could also lead to unintended disclosure and social isolation. These data provide a novel explanatory model of treatment refusal, recognizing perceived risks and social costs incurred when disclosing one’s status through treatment initiation. Our findings suggest that improving engagement in care for people living with HIV in South Africa will require optimizing social integration and connectivity for those who test positive

A homomorphism between link and XXZ modules over the periodic Temperley-Lieb algebra

We study finite loop models on a lattice wrapped around a cylinder. A section of the cylinder has N sites. We use a family of link modules over the periodic Temperley-Lieb algebra EPTL_N(\beta, \alpha) introduced by Martin and Saleur, and Graham and Lehrer. These are labeled by the numbers of sites N and of defects d, and extend the standard modules of the original Temperley-Lieb algebra. Beside the defining parameters \beta=u^2+u^{-2} with u=e^{i\lambda/2} (weight of contractible loops) and \alpha (weight of non-contractible loops), this family also depends on a twist parameter v that keeps track of how the defects wind around the cylinder. The transfer matrix T_N(\lambda, \nu) depends on the anisotropy \nu and the spectral parameter \lambda that fixes the model. (The thermodynamic limit of T_N is believed to describe a conformal field theory of central charge c=1-6\lambda^2/(\pi(\lambda-\pi)).) The family of periodic XXZ Hamiltonians is extended to depend on this new parameter v and the relationship between this family and the loop models is established. The Gram determinant for the natural bilinear form on these link modules is shown to factorize in terms of an intertwiner i_N^d between these link representations and the eigenspaces of S^z of the XXZ models. This map is shown to be an isomorphism for generic values of u and v and the critical curves in the plane of these parameters for which i_N^d fails to be an isomorphism are given.Comment: Replacement of "The Gram matrix as a connection between periodic loop models and XXZ Hamiltonians", 31 page

The tomato Prf complex is a molecular trap for bacterial effectors based on Pto transphosphorylation

The bacteria Pseudomonas syringae is a pathogen of many crop species and one of the model pathogens for studying plant and bacterial arms race coevolution. In the current model, plants perceive bacteria pathogens via plasma membrane receptors, and recognition leads to the activation of general defenses. In turn, bacteria inject proteins called effectors into the plant cell to prevent the activation of immune responses. AvrPto and AvrPtoB are two such proteins that inhibit multiple plant kinases. The tomato plant has reacted to these effectors by the evolution of a cytoplasmic resistance complex. This complex is compromised of two proteins, Prf and Pto kinase, and is capable of recognizing the effector proteins. How the Pto kinase is able to avoid inhibition by the effector proteins is currently unknown. Our data shows how the tomato plant utilizes dimerization of resistance proteins to gain advantage over the faster evolving bacterial pathogen. Here we illustrate that oligomerisation of Prf brings into proximity two Pto kinases allowing them to avoid inhibition by the effectors by transphosphorylation and to activate immune responses

Mapping of pigmentation QTL on an anchored genome assembly of the cichlid fish, Metriaclima zebra

Pigmentation patterns are one of the most recognizable phenotypes across the animal kingdom. They play an important role in camouflage, communication, mate recognition and mate choice. Most progress on understanding the genetics of pigmentation has been achieved via mutational analysis, with relatively little work done to understand variation in natural populations. Pigment patterns vary dramatically among species of cichlid fish from Lake Malawi, and are thought to be important in speciation. In this study, we crossed two species, Metriaclima zebra and M. mbenjii, that differ in several aspects of their body and fin color. We genotyped 798 SNPs in 160 F2 male individuals to construct a linkage map that was used to identify quantitative trait loci (QTL) associated with the pigmentation traits of interest. We also used the linkage map to anchor portions of the M. zebra genome assembly. We constructed a linkage map consisting of 834 markers in 22 linkage groups that spanned over 1,933 cM. QTL analysis detected one QTL each for dorsal fin xanthophores, caudal fin xanthophores, and pelvic fin melanophores. Dorsal fin and caudal fin xanthophores share a QTL on LG12, while pelvic fin melanophores have a QTL on LG11. We used the mapped markers to anchor 66.5% of the M. zebra genome assembly. Within each QTL interval we identified several candidate genes that might play a role in pigment cell development. This is one of a few studies to identify QTL for natural variation in fish pigmentation. The QTL intervals we identified did not contain any pigmentation genes previously identified by mutagenesis studies in other species. We expect that further work on these intervals will identify new genes involved in pigment cell development in natural populations

A Qualitative Analysis of Factors Influencing HPV Vaccine Uptake in Soweto, South Africa among Adolescents and Their Caregivers

Background: In South Africa, the prevalence of oncogenic Human Papillomavirus (HPV) may be as high as 64%, and cervical cancer is the leading cause of cancer-related death among women. The development of efficacious prophylactic vaccines has provided an opportunity for primary prevention. Given the importance of psycho-social forces in vaccine uptake, we sought to elucidate factors influencing HPV vaccination among a sample of low-income South African adolescents receiving the vaccine for the first time in Soweto. Methods: The HPV vaccine was introduced to adolescents in low-income townships throughout South Africa as part of a nationwide trial to understand adolescent involvement in future vaccine research targeting human immunodeficiency virus (HIV). We performed in-depth semi-structured interviews with purposively-sampled adolescents and their care providers to understand what forces shaped HPV vaccine uptake. Interviews were recorded, transcribed, translated, and examined using thematic analysis. Results: Of 224 adolescents recruited, 201 initiated the vaccine; 192 (95.5%) received a second immunization; and 164 (81.6%) completed three doses. In our qualitative study of 39 adolescent-caregiver dyads, we found that factors driving vaccine uptake reflected a socio-cultural backdrop of high HIV endemnicity, sexual violence, poverty, and an abundance of female-headed households. Adolescents exercised a high level of autonomy and often initiated decision-making. Healthcare providers and peers provided support and guidance that was absent at home. The impact of the HIV epidemic on decision-making was substantial, leading participants to mistakenly conflate HPV and HIV. Conclusions: In a setting of perceived rampant sexual violence and epidemic levels of HIV, adolescents and caregivers sought to decrease harm by seeking a vaccine targeting a sexually transmitted infection (STI). Despite careful consenting, there was confusion regarding the vaccine’s target. Future interventions promoting STI vaccines will need to provide substantial information for participants, particularly adolescents who may exercise a significant level of autonomy in decision-making

The Influence of Electrochemical Aging on Bead-Blasted Nickel Electrodes for the Oxygen Evolution Reaction

The oxygen evolution reaction (OER) is of importance to both electrochemical energy conversion and energy storage. Low-cost, non-precious metal electrocatalysts that can withstand high operational current densities will likely be the best candidates for meeting the commercial needs for a range of OER applications. In addition to electrode composition, the surface morphology of gas evolving electrodes can affect their efficiency and performance. In this work, we demonstrate the influence of electrochemical aging on the performance of micro- and nanoscale textures for the OER. A series of textured Ni electrodes were prepared by rapid, scalable techniques, which included the use of bead-blasting. Two distinct approaches to induce the formation of the active Ni (oxy)hydroxide phase were conducted by electrochemical aging using cyclic voltammetry (CV) methods. The influence of the aging technique was assessed and correlated to the performance of these surface textures. Differences in the morphology of these textures and their resulting surface areas were estimated using three-dimensional (3D) reconstructions obtained from electron microscopy analyses. Focused ion beam (FIB) milling was also performed on the bead-blasted electrodes to visualize buried cracks and voids. The potential required for the OER at an applied current density of 500 mA/cm2 exhibited a reduction of 0.7 V for the electrodes aged by the steady-state treatment. The OER performance of the textured electrodes were found to correlate to both the electrode surface morphology and the type of electrochemical aging applied to the electrodes