Spin-phonon coupling in multiferroic RCrO3_3 (R-Y, Lu, Gd, Eu, Sm): A Raman study

Raman study on a select few orthochromites, RCrO$_3$ (R = Y, Lu, Gd, Eu and Sm) shows that the phonon behavior at TN in compounds with magnetic R-ion (Gd and Sm) is remarkably different from that of non-magnetic R-ion (Y, Lu and Eu). While anomalies in most of the observed phonon frequencies in all these compounds may result from the distortion of CrO$_6$ octahedra due to size effect and magnetostriction arising from Cr-ordering, the anomalous behavior of their linewidths observed at TN for the compounds with only magnetic R-ion suggests spin-phonon coupling. The presence of spin-phonon coupling and the anomalies in the low frequency modes related to R-ion motion in orthochromites (R = Gd and Sm) support the suggestion that the coupling between 4f-3d moments play important role in inducing switchable electric polarization.Comment: 6 pages (two column format), 7 figures; The updated version of the manuscript can be found at Euro. Phys. Lett. 101, 17008 (2013

Perceived barriers to management of chronic kidney disease

INTRODUCTION: The number of patients with chronic kidney disease (CKD) is gradually increasing in developing countries such as Rwanda. Barriers to the management of CKD from nurses' perspectives is not an area that has been well explored. This study aimed to assess the perceived barriers to CKD management from the perspective of nurses working at the referral hospitals in Rwanda.METHODS: The study used a cross-sectional research design. The study setting was selected referral hospitals in Kigali. A convenience sample of 55 nurses was obtained and data was collected using a self-administered questionnaire. Analyses were done using descriptive and inferential statistics in the SPSS application.RESULTS: Respondents identified the most barriers to management of CKD as: limited knowledge of CKD (96%) and its risk factor of glomerulonephritis (93%), limited information of dialysis (98%) and fluid restriction (95%) treatment as well as a lack of further training on nephrology nursing (93%). Shortage of nephrologists and nurses (98%) and a multidisciplinary care team (95%) were resource barriers. Other barriers were limited knowledge of CKD risk factors: hypertension (78%) and HIV/AIDS (80%), limited in-service training (69%), and non-adherence (86%). The experience of respondents was associated with limited knowledge of CKD risk factors: hypertension (P =0.001), diabetes (P=0.001) and HIV/AIDS (P=0.040). The level of nursing obtained by the respondents was associated with a lack of further special training (p=0. 001), limited in-service training (P=0.028) and non-adherence of CKD patients (P=0.017).CONCLUSION: Barriers to CKD management in Rwanda are evident. There is a need for in-service training for nurses in order to improve the proper treatment of the CKD population.&nbsp

Sequencing of RDR6-dependent double-stranded RNAs reveals novel features of plant siRNA biogenesis

Biogenesis of trans-acting siRNAs (tasiRNAs) is initiated by miRNA-directed cleavage of TAS gene transcripts and requires RNA-dependent RNA polymerase 6 (RDR6) and Dicer-like 4 (DCL4). Here, we show that following miR173 cleavage the entire polyadenylated parts of Arabidopsis TAS1a/b/c and TAS2 transcripts are converted by RDR6 to double-stranded (ds)RNAs. Additionally, shorter dsRNAs are produced following a second cleavage directed by a TAS1c-derived siRNA. This tasiRNA and miR173 guide Argonaute 1 complexes to excise the segments from TAS2 and three TAS1 transcripts including TAS1c itself to be converted to dsRNAs, which restricts siRNA production to a region between the two cleavage sites. TAS1c is also feedback regulated by a cis-acting siRNA. We conclude that TAS1c generates a master siRNA that controls a complex network of TAS1/TAS2 siRNA biogenesis and gene regulation. TAS1/TAS2 short dsRNAs produced in this network are processed by DCL4 from both ends in distinct registers, which increases repertoires of tasiRNA

N,N′-Bis(2,2,3,3,4,4,4-hepta­fluoro­butyl)naphthalene-1,4:5,8-tetra­carboximide

The title mol­ecule, C22H8F14N2O4, lies across a crystallographic inversion center with the naphthalene diimide core essentially planar (mean deviation from plane is 0.0583 Å). The CF2 groups in the perfluorobutyl chains are in an energetically favorable all trans conformation. In the crystal structure, mol­ecules are packed in slightly displaced layers so that the side chains overlap the aromatic naphthalene diimide rings, thus minimizing any possible π–π overlap

Utility of biotechnology based decision making tools in postharvest grain pest management: an Australian case study

A major concern for the Australian grain industry in recent years is the constant threat of resistance to the key disinfectant phosphine in a range of stored grain pests. The need to maintain the usefulness of phosphine and to contain the development of resistance are critical to international market access for Australian grain. Strong levels of resistance have already been established in major pests including the lesser grain borer, Rhyzopertha dominica (F.), the red flour beetle, Tribolium castaneum (Herbst), and most recently in the rusty grain beetle Cryptolestes ferrugineus (Stephens). As a proactive integrated resistance management strategy, new fumigation protocols are being developed in the laboratory and verified in large-scale field trials in collaboration with industry partners. To aid this development, we have deployed advanced molecular diagnostic tools to accurately determine the strength and frequency of key phosphine resistant insect pests and their movement within a typical Australian grain value chain. For example, two major bulk storage facilities based at Brookstead and Millmerran in southeast Queensland, Australia, were selected as main nodes and several farms and feed mills located in and around these two sites at a scale of 25 to 100 km radius were selected and surveyed. We determined the type, pattern, frequency as well as the distribution of resistance alleles accurately for two major pests, R. dominica and T. castaneum. Overall, this information along with the phenotypic data, provide a basis for designing key intervention strategies in managing resistance problems in the study area

Transcriptomic analysis of s-methoprene resistance in the lesser grain borer, Rhyzopertha dominica, and evaluation of piperonyl butoxide as a resistance breaker

The lesser grain borer, Rhyzopertha dominica is a serious pest of stored grains. Fumigation and contact insecticides play a major role in managing this pest globally. While insects are developing genetic resistance to chemicals, hormonal analogues such as s-methoprene play a key role in reducing general pest pressure as well as managing pest populations that are resistant to fumigants and neurotoxic contact insecticides. However, resistance to s-methoprene has been reported in R. dominica with some reports showing a remarkable high resistance, questioning the use of this compound and other related analogues in grain protection. The current study attempts to identify possible molecular mechanisms that contribute in resistance to s-methoprene in R. dominica

Outcomes of less invasive J-incision approach to aortic valve surgery

ObjectiveLess invasive approaches to aortic valve surgery are increasingly used; however, few studies have investigated their impact on outcome. We sought to compare clinical outcomes after these approaches with full sternotomy using propensity-matching methods.MethodsFrom January 1995 to January 2004, a total of 2689 patients underwent isolated aortic valve surgery, 1193 via upper J-hemisternotomy and 1496 via full sternotomy. Because of important differences in patient characteristics between these groups, a propensity score based on 42 variables was used to obtain 832 well-matched patient pairs (70% of possible cases).ResultsIn-hospital mortality was identical for propensity-matched patients, 0.96% (8 in each). Occurrences of stroke (P > .9), renal failure (P = .8), and myocardial infarction (P = .7) were similar. However, 24-hour mediastinal drainage was a third less after less invasive surgery (median, 250 vs 350 mL; P < .0001), and fewer patients received transfusions (24% vs 34%; P < .0001). More patients undergoing less invasive surgery were extubated in the operating room (12% vs 1.6%; P < .0001), postoperative forced 1-second expiratory volume was higher (P = .009), and fewer had respiratory failure (P = .01). Early after operation, pain scores were lower (P < .0001) after less-invasive surgery and postoperative length of stay shorter (P < .0001).ConclusionsWithin that portion of the spectrum of isolated aortic valve surgery where propensity matching was possible, minimally invasive aortic valve surgery had not only cosmetic advantages, but blood product use, respiratory, pain, and resource utilization advantages over full sternotomy, and no apparent detriments. Less invasive aortic valve surgery should be considered for most aortic valve operations

Utility of biotechnology based decision making tools in postharvest grain pest management: an Australian case study

A major concern for the Australian grain industry in recent years is the constant threat of resistance to the key disinfectant phosphine in a range of stored grain pests. The need to maintain the usefulness of phosphine and to contain the development of resistance are critical to international market access for Australian grain. Strong levels of resistance have already been established in major pests including the lesser grain borer, Rhyzopertha dominica (F.), the red flour beetle, Tribolium castaneum (Herbst), and most recently in the rusty grain beetle Cryptolestes ferrugineus (Stephens). As a proactive integrated resistance management strategy, new fumigation protocols are being developed in the laboratory and verified in large-scale field trials in collaboration with industry partners. To aid this development, we have deployed advanced molecular diagnostic tools to accurately determine the strength and frequency of key phosphine resistant insect pests and their movement within a typical Australian grain value chain. For example, two major bulk storage facilities based at Brookstead and Millmerran in southeast Queensland, Australia, were selected as main nodes and several farms and feed mills located in and around these two sites at a scale of 25 to 100 km radius were selected and surveyed. We determined the type, pattern, frequency as well as the distribution of resistance alleles accurately for two major pests, R. dominica and T. castaneum. Overall, this information along with the phenotypic data, provide a basis for designing key intervention strategies in managing resistance problems in the study area

Persistent risk of subsequent procedures and mortality in patients after interrupted aortic arch repair: A Congenital Heart Surgeons' Society study

ObjectiveMultiple subsequent procedures directed at the arch and/or the left ventricular outflow tract are frequently required after interrupted aortic arch repair. We the investigated patterns and factors associated with these subsequent procedures and mortality.MethodsWe reviewed the data from 447 patients with interrupted aortic arch at 33 institutions enrolled from 1987 to 1997. We classified the subsequent procedures by type (catheter-based or surgical) and focus (arch, left ventricular outflow tract, and “other” cardiovascular lesions). We used competing risks and modulated renewal analysis to explore subsequent procedures.ResultsThere were 158 subsequent arch and 100 left ventricular outflow tract procedures. Freedom from death at 21 years was 60% overall. The risk of additional subsequent arch procedures decreased after the first subsequent arch procedure in the acute phase, but did not significantly change in the chronic phase. The risk of additional subsequent left ventricular outflow tract procedures increased after the first subsequent left ventricular outflow tract procedure in the chronic phase. The risk factors for subsequent arch procedures and mortality, but not for subsequent outflow track procedures, were related in a complex way to previous procedures and their timing.ConclusionsInterrupted aortic arch is a chronic disease in which patients often undergo multiple subsequent procedures with persistent risk for additional intervention and mortality. The risk factors are related to the nature and timing of previous procedures and to the morphology and details of the index procedure. Interrupted aortic arch should be considered a chronic disorder

A systematic review and meta-analysis to determine the contribution of mr imaging to the diagnosis of foetal brain abnormalities In Utero.

OBJECTIVES: This systematic review was undertaken to define the diagnostic performance of in utero MR (iuMR) imaging when attempting to confirm, exclude or provide additional information compared with the information provided by prenatal ultrasound scans (USS) when there is a suspicion of foetal brain abnormality. METHODS: Electronic databases were searched as well as relevant journals and conference proceedings. Reference lists of applicable studies were also explored. Data extraction was conducted by two reviewers independently to identify relevant studies for inclusion in the review. Inclusion criteria were original research that reported the findings of prenatal USS and iuMR imaging and findings in terms of accuracy as judged by an outcome reference diagnosis for foetal brain abnormalities. RESULTS: 34 studies met the inclusion criteria which allowed diagnostic accuracy to be calculated in 959 cases, all of which had an outcome reference diagnosis determined by postnatal imaging, surgery or autopsy. iuMR imaging gave the correct diagnosis in 91 % which was an increase of 16 % above that achieved by USS alone. CONCLUSION: iuMR imaging makes a significant contribution to the diagnosis of foetal brain abnormalities, increasing the diagnostic accuracy achievable by USS alone. KEY POINTS: • Ultrasound is the primary modality for monitoring foetal brain development during pregnancy • iuMRI used together with ultrasound is more accurate for detecting foetal brain abnormalities • iuMR imaging is most helpful for detecting midline brain abnormalities • The moderate heterogeneity of reviewed studies may compromise findings