Nonlinear wavelength selection in surface faceting under electromigration

We report on the control of the faceting of crystal surfaces by means of surface electromigration. When electromigration reinforces the faceting instability, we find perpetual coarsening with a wavelength increasing as $t^{1/2}$. For strongly stabilizing electromigration, the surface is stable. For weakly stabilizing electromigration, a cellular pattern is obtained, with a nonlinearly selected wavelength. The selection mechanism is not caused by an instability of steady-states, as suggested by previous works in the literature. Instead, the dynamics is found to exhibit coarsening {\it before} reaching a continuous family of stable non-equilibrium steady-states.Comment: 5 pages, 4 figures, submitte

Multilevel Analysis of Trachomatous Trichiasis and Corneal Opacity in Nigeria : The Role of Environmental and Climatic Risk Factors on the Distribution of Disease.

Funding: Jennifer L Smith was supported by the International Trachoma Initiative through a grant from the Bill and Melinda Gates Foundation. Anthony Solomon is a Wellcome Trust Intermediate Clinical Fellow (098521). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

Post-partum follow-up of women with gestational diabetes mellitus: Effectiveness, determinants, and barriers

Background: Despite the recommendations for postpartum blood glucose monitoring post gestational diabetes mellitus (GDM); scientific evidence reveals that these recommendations may not be fully complied to. This study aimed to follow-up women up to 2 years post-delivery with pregnancies complicated by GDM and healthy controls to assess this fact.Methods: Women with GDM (n = 78) and normal glucose tolerant (n = 89) delivered in 2014 were followed up for 2 years. They were informed and enquired via telephone about their blood glucose screening, physical activity, postpartum complications, and current weight status of mother and baby.Results: Women with previous GDM were older and reported higher body weight 2 years post-delivery. At the 2 year follow-up, n = 11 (14.1%) participants had developed diabetes, all with previous GDM. Both weight at birth (3.8 ± 0.5 kg) and at 2-year (10.7 ± 2.3 kg) for the babies born to GDM mothers was significantly higher than the NGT group babies (2.6 ± 0.63 and 7.1 ± 1.4 kg; p \u3c .05). Only 27 women regularly opted for T2DM screening via monitoring blood glucose or HbA1c levels postpartum. The top reason for failed screening included: believing that GDM would disappear after delivery, and being occupied with the baby.Conclusions: The high incidence of T2DM in women with previous GDM is an alarming finding. Given this trend, systematic follow-up programs are needed to reduce obesity and diabetes risk

Should We Rush to Implement Password-less Single Factor FIDO2 based Authentication?

© 2020 IEEE. Fast Identity Online (FIDO) Alliance and W3C have defined a set of specifications (called FIDO2) that allows a user to replace the password based authentication system. However, none of the high profile web sites have implemented FIDO2 yet as password-less single factor (SF) authentication (password-less SF). In this paper, we analyze the set of factors that make websites reluctant to adopt password-less FIDO SF authentication. We start by comparing the threat models of password-less FIDO SF authentication with password-based SF authentication. Our analysis shows that although password-based authentication is less secure than FIDO SF authentication, other factors related to the usability of FIDO security keys and FIDO based authentication system, the non-consideration of enterprise requirements and the lack of specifications regarding account recovery/deletion and suspension are the main obstacles to the adoption of password-less FIDO SF authentication

Changing physical appearance preferences in the United Arab Emirates

Rapid economic growth in the United Arab Emirates (UAE) has impacted traditional ways of life rooted in Bedouin traditions and Islamic values. Research undertaken within the UAE suggests that a thin body-image ideal is widespread, as are abnormal eating attitudes and extreme dietary behaviours. However, this regional research has been exclusively cross-sectional, precluding conclusions about the temporal dynamics or nascence of these phenomena. This study explores changes in physical appearance preferences in the UAE over the past two decades. Interviews were undertaken with five khatabaat (marriage brokers), who were asked to report the attributes typically requested by those seeking wives, both now, and in the past. Thematic analysis of these data highlighted differences between the attributes currently deemed desirable, and those deemed desirable in the recent past. These findings are discussed in the context of the nation\u27s rapid socio-economic change, and their implications for body-image and eating-related problems. © 2014 © 2014 Taylor & Francis

Comparison of the virulence markers of helicobacter pylori and their associated diseases in patients from Pakistan and Afghanistan

BACKGROUND/AIM: Helicobacter pylori is a Gram-negative bacteria, which is associated with development of gastroduodenal diseases. The prevalence of H. pylori and the virulence markers cytotoxin-associated gene A and E (cagA, cagE) and vacuolating-associated cytotoxin gene (vacA) alleles varies in different parts of the world. H. pylori virulence markers cagA, cagE, and vacA alleles in local and Afghan nationals with H. pylori-associated gastroduodenal diseases were studied. PATIENTS AND METHODS:Two hundred and ten patients with upper gastrointestinal symptoms and positive for H. pylori by the urease test and histology were included. One hundred and nineteen were local nationals and 91 were Afghans. The cagA, cagE, and vacA allelic status was determined by polymerase chain reaction. RESULTS:The nonulcer dyspepsia (NUD) was common in the Afghan patients (P = 0.025). In Afghan H. pylori strains, cagA was positive in 14 (82%) with gastric carcinoma (GC) compared with 29 (45%) with NUD (P = 0.006), whereas cagE was positive in 11 (65%) with GC and 4 (67%) with duodenal ulcer (DU) compared with 12 (18%) with NUD (P \u3c 0.001 and 0.021, respectively). The vacA s1a/b1was positive in 10 (59%) of GC compared with 20 (31%) in NUD (P = 0.033). In Pakistani strains, cagE was positive in 12 (60%) with GC, 7 (58%) with GU, 12 (60%) with DU compared with 11 (16%) with NUD (P \u3c 0.001, 0.004, and \u3c 0.001, respectively). In Pakistani strains, cagA/s1a/m1 was 39 (33%) compared with Afghans in 17 (19%) (P = 0.022). Moderate to severe mucosal inflammation was present in 51 (43%) Pakistani patients compared with 26 (28%) (P = 0.033) in Afghans. It was also associated with grade 1 lymphoid aggregate development in Pakistani patients 67 (56%) compared with 36 (40%) (P = 0.016) in Afghans. CONCLUSION: Distribution of H. pylori virulence marker cagE with DU was similar in Afghan and Pakistan H. pylori strains. Chronic active inflammation was significantly associated with Pakistani H. pylori strains

Risk Stratification and Early Oncologic Outcomes Following Robotic Prostatectomy

Results of this study suggest that robotic prostatectomy provides good cancer outcomes for clinically localized disease

Low-Cost Single Chamber MFC Integrated With Novel Lignin-Based Carbon Fiber Felt Bioanode for Treatment of Recalcitrant Azo Dye

A flow through anaerobic microbial fuel cell (MFC) was designed and optimized for efficient treatment of recalcitrant textile wastewater. The membrane-less MFC was first time fabricated with a unique combination of electrodes, a novel bioanode of synthesized lignin-based electrospun carbon fiber supporting a biofilm of Geobacter sulfurreducens for acetate oxidation and an air-breathing cathode, consisting of a pyrolyzed macrocycle catalyst mixture on carbon bonded by polytetrafluoroethylene (PTFE). The effects of different organic loadings of acetate along with Acid Orange (AO5), operation time and ionic strength of auxiliary salts (conductivity enhancers) were investigated and responses in terms of polarization and degradation were studied. In addition, the decomposition of the organic species and the degradation of AO5 along with its metabolites and degraded products (2-aminobenzenesulfonic acid) were determined by chemical oxygen demand (COD) analysis, UV-Vis spectrophotometry and high-performance liquid chromatography (UV-HPLC) techniques. SEM and TEM images were also used to find out the biocompatibility of the microbes on lignin-based electrospun carbon felt anode and the morphology of the cathode. Reduction and breakage of the azo bond of AO5 occurs presumably as a side reaction, resulting in the formation of 2-aminobenzenesulfonic acid and unidentified aromatic amines. Maximum current density of anode 0.59 Am−2 and power density of 0.12 Wm−2 were obtained under optimized conditions. As a result, decolouration of AO5 and chemical oxygen demand (COD) removal efficiency was 81 and 58%, respectively. These results revealed that the low-cost MFC assembly can offer significant potential for anaerobic decolouration of recalcitrant textile wastewater

Coccolithophore biodiversity controls carbonate export in the Southern Ocean

Southern Ocean waters are projected to undergo profound changes in their physical and chemical properties in the coming decades. Coccolithophore blooms in the Southern Ocean are thought to account for a major fraction of the global marine calcium carbonate (CaCO3) production and export to the deep sea. Therefore, changes in the composition and abundance of Southern Ocean coccolithophore populations are likely to alter the marine carbon cycle, with feedbacks to the rate of global climate change. However, the contribution of coccolithophores to CaCO3 export in the Southern Ocean is uncertain, particularly in the circumpolar subantarctic zone that represents about half of the areal extent of the Southern Ocean and where coccolithophores are most abundant. Here, we present measurements of annual CaCO3 flux and quantitatively partition them amongst coccolithophore species and heterotrophic calcifiers at two sites representative of a large portion of the subantarctic zone. We find that coccolithophores account for a major fraction of the annual CaCO3 export, with the highest contributions in waters with low algal biomass accumulations. Notably, our analysis reveals that although Emiliania huxleyi is an important vector for CaCO3 export to the deep sea, less abundant but larger species account for most of the annual coccolithophore CaCO3 flux. This observation contrasts with the generally accepted notion that high particulate inorganic carbon accumulations during the austral summer in the subantarctic Southern Ocean are mainly caused by E. huxleyi blooms. It appears likely that the climate-induced migration of oceanic fronts will initially result in the poleward expansion of large coccolithophore species increasing CaCO3 production. However, subantarctic coccolithophore populations will eventually diminish as acidification overwhelms those changes. Overall, our analysis emphasizes the need for species-centred studies to improve our ability to project future changes in phytoplankton communities and their influence on marine biogeochemical cycles.info:eu-repo/semantics/publishedVersio