Cohomological finiteness conditions for a class of metabelian groups

We consider a class of metabelian groups first studied by Baumslag and Stammbach and we show that these groups are consistent with the Bieri-Groves conjecture which relates cohomological finiteness conditions to the Bieri-Neumann-Strebel sigma invariant.Comment: 10 pages Accepted for publication in the Bulletin of the London Mathematical Societ

Effects of Clariva Complete Beans Seed Treatment on Heterodera glycines Reproduction and Soybean Yield in Iowa

In recent years, nematode-protectant seed treatments have become available to supplement resistant soybean cultivars to manage soybean cyst nematode (Heterodera glycines; SCN). Twenty-seven small-plot and 18 strip-trial experiments were conducted comparing the effects of Clariva Complete Beans (CCB) and CruiserMaxx Advanced plus Vibrance (CMV) on SCN reproduction and soybean yield on a moderately resistant (2014) and resistant (2015 to 2016) soybean cultivar. Yield data were collected, and an SCN reproductive factor was calculated by dividing final (at harvest) SCN egg population densities by initial (at planting) population densities from soil samples collected in each small plot or sampled area in the strip trials. Relative to the CMV treatment, CCB significantly decreased SCN reproductive factor in two small-plot experiments (one each in 2014 and 2015) but not in any of the strip trials in any year. Soybean yields were significantly greater with CCB versus CMV in 5 of the 18 strip trials but not in any of the small-plot experiments, even when there were significant decreases in SCN reproduction. For unknown reasons, CCB significantly decreased yields in two small-plot experiments and at one strip-trial location. In summary, the effects of CCB seed treatment on SCN reproduction and soybean yields were variable in the years that these experiments were conducted in Iowa

A training, assessment and feedback package for the trainee shoulder sonographer

Diagnostic ultrasound of the shoulder is recognised as being one of the most technically challenging aspects of musculoskeletal ultrasound to master. It has a steep learning curve and makes gaining competency a time-intensive training process for both the trainee and their trainer. This article describes a training, assessment and feedback package developed within the framework of a Consortium for the Accreditation of Sonographic Education approved post-graduate ultrasound course. The package comprises: (i) a shoulder diagnostic ultrasound scan protocol with definition of findings, differential diagnosis and pro forma for recording scan findings, (ii) an assessment form for performance of shoulder diagnostic ultrasound scans with assessment criteria and (iii) a combined performance assessment and scan findings form, for each tissue being imaged. The package has been developed using medical education principles and provides a mechanism for trainees to follow an internationally recognised protocol. Supplementary information includes the differential diagnostic process used by an expert practitioner, which can otherwise be difficult to elicit. The package supports the trainee with recording their findings quickly and consistently and helps the trainee and trainer to explicitly recognise the challenges of scanning different patients or pathologies. It provides a mechanism for trainers to quantify and trainees to evidence their emerging competency. The package detailed in this article is therefore proposed for use in shoulder ultrasound training and its principles could be adapted for other musculoskeletal regions or other ultrasound disciplines

Population Pharmacokinetic Modeling of Total and Free Ceftriaxone in Critically Ill Children and Young Adults and Monte Carlo Simulations Support Twice Daily Dosing for Target Attainment

Critical illness, including sepsis, causes significant pathophysiologic changes that alter the pharmacokinetics (PK) of antibiotics. Ceftriaxone is one of the most prescribed antibiotics in patients admitted to the pediatric intensive care unit (PICU). We sought to develop population PK models of both total ceftriaxone and free ceftriaxone in children admitted to a single-center PICU using a scavenged opportunistic sampling approach. We tested if the presence of sepsis and phase of illness (before or after 48 h of antibiotic treatment) altered ceftriaxone PK parameters. We performed Monte Carlo simulations to evaluate whether dosing regimens commonly used in PICUs in the United States (50 mg/kg of body weight every 12 h versus 24 h) resulted in adequate antimicrobial coverage. We found that a two-compartment model best described both total and free ceftriaxone concentrations. For free concentrations, the population clearance value is 6.54 L/h/70 kg, central volume is 25.4 L/70 kg, and peripheral volume is 19.6 L/70 kg. For both models, we found that allometric weight scaling, postmenstrual age, creatinine clearance, and daily highest temperature had significant effects on clearance. The presence of sepsis or phase of illness did not have a significant effect on clearance or volume of distribution. Monte Carlo simulations demonstrated that to achieve free concentrations above 1 mu g/ml for 100% of the dosing intervals, a dosing regimen of 50 mg/kg every 12 h is recommended for most patients. A continuous infusion could be considered if the target is to maintain free concentrations four times above the MICs (4 mu g/ml)

Bladesense – a novel approach for measuring dynamic helicopter rotor blade deformation

Technologies that allow accurate measurement of rotorblade dynamics can impact almost all areas of the rotorcraft sector; ranging from maintenance all the way to blade design. The BladeSense project initiated in 2016 aims to take a step in developing and demonstrating such a capability using novel fibre optic sensors that allow direct shape measurement. In this article the authors summarise key project activities in modelling and simulation, instrumentation development and ground testing. The engineering approach and associated challenges and achievements in each of these disciplines are discussed albeit briefly. This ranges from the use of computational aerodynamics and structural modelling to predict blade dynamics to the development of direct fibre optic shape sensing that allows measurements above 1kHz over numerous positions on the blade. Moreover, the development of the prototype onboard system that overcomes the challenge of transferring data between the rotating main rotor to the fixed fuselage frames is also discussed

Identification of KIF21A mutations as a rare cause of congenital fibrosis of the extraocular muscles type 3 (CFEOM3).

PURPOSE. Three congenital fibrosis of the extraocular muscles phenotypes (CFEOM1-3) have been identified. Each represents a specific form of paralytic strabismus characterized by congenital restrictive ophthalmoplegia, often with accompanying ptosis. It has been demonstrated that CFEOM1 results from mutations in KIF21A and CFEOM2 from mutations in PHOX2A. This study was conducted to determine the incidence of KIF21A and PHOX2A mutations among individuals with the third CFEOM phenotype, CFEOM3. METHODS. All pedigrees and sporadic individuals with CFEOM3 in the authors' database were identified, whether the pedigrees were linked or consistent with linkage to the FEOM1, FEOM2, and/or FEOM3 loci was determined, and the appropriate pedigrees and the sporadic individuals were screened for mutations in KIF21A and PHOX2A. RESULTS. Twelve CFEOM3 pedigrees and 10 CFEOM3 sporadic individuals were identified in the database. The structures of eight of the pedigrees permitted the generation of meaningful linkage data. KIF21A was screened in 17 probands, and mutations were identified in two CFEOM3 pedigrees. One pedigree harbored a novel mutation (2841G-->A, M947I) and one harbored the most common and recurrent of the CFEOM1 mutations identified previously (2860C-->T, R954W). None of CFEOM3 pedigrees or sporadic individuals harbored mutations in PHOX2A. CONCLUSIONS. The results demonstrate that KIF21A mutations are a rare cause of CFEOM3 and that KIF21A mutations can be nonpenetrant. Although KIF21A is the first gene to be associated with CFEOM3, the results imply that mutations in the unidentified FEOM3 gene are the more common cause of this phenotype

The Chandra Deep Wide-field Survey: A New Chandra Legacy Survey in the Boötes Field. I. X-Ray Point Source Catalog, Number Counts, and Multiwavelength Counterparts

We present a new, ambitious survey performed with the Chandra X-ray Observatory of the 9.3 deg2 Boötes field of the NOAO Deep Wide-Field Survey. The wide field probes a statistically representative volume of the universe at high redshift. The Chandra Deep Wide-field Survey exploits the excellent sensitivity and angular resolution of Chandra over a wide area, combining 281 observations spanning 15 yr, for a total exposure time of 3.4 Ms, and detects 6891 X-ray point sources down to limiting fluxes of 4.7 × 10−16, 1.5 × 10−16, and 9 ×10−16 erg cm−2 s−1 in the 0.5–7, 0.5–2, and 2–7 keV bands, respectively. The robustness and reliability of the detection strategy are validated through extensive, state-of-the-art simulations of the whole field. Accurate number counts, in good agreement with previous X-ray surveys, are derived thanks to the uniquely large number of point sources detected, which resolve 65.0% ± 12.8% of the cosmic X-ray background between 0.5 and 2 keV and 81.0% ± 11.5% between 2 and 7 keV. Exploiting the wealth of multiwavelength data available on the field, we assign redshifts to ~94% of the X-ray sources, estimate their obscuration, and derive absorption-corrected luminosities. We provide an electronic catalog containing all of the relevant quantities needed for future investigations

MECP2 Isoform-Specific Vectors with Regulated Expression for Rett Syndrome Gene Therapy

BACKGROUND:Rett Syndrome (RTT) is an Autism Spectrum Disorder and the leading cause of mental retardation in females. RTT is caused by mutations in the Methyl CpG-Binding Protein-2 (MECP2) gene and has no treatment. Our objective is to develop viral vectors for MECP2 gene transfer into Neural Stem Cells (NSC) and neurons suitable for gene therapy of Rett Syndrome. METHODOLOGY/PRINCIPAL FINDINGS:We generated self-inactivating (SIN) retroviral vectors with the ubiquitous EF1alpha promoter avoiding known silencer elements to escape stem-cell-specific viral silencing. High efficiency NSC infection resulted in long-term EGFP expression in transduced NSC and after differentiation into neurons. Infection with Myc-tagged MECP2-isoform-specific (E1 and E2) vectors directed MeCP2 to heterochromatin of transduced NSC and neurons. In contrast, vectors with an internal mouse Mecp2 promoter (MeP) directed restricted expression only in neurons and glia and not NSC, recapitulating the endogenous expression pattern required to avoid detrimental consequences of MECP2 ectopic expression. In differentiated NSC from adult heterozygous Mecp2(tm1.1Bird)+/- female mice, 48% of neurons expressed endogenous MeCP2 due to random inactivation of the X-linked Mecp2 gene. Retroviral MECP2 transduction with EF1alpha and MeP vectors rescued expression in 95-100% of neurons resulting in increased dendrite branching function in vitro. Insulated MECP2 isoform-specific lentiviral vectors show long-term expression in NSC and their differentiated neuronal progeny, and directly infect dissociated murine cortical neurons with high efficiency. CONCLUSIONS/SIGNIFICANCE:MeP vectors recapitulate the endogenous expression pattern of MeCP2 in neurons and glia. They have utility to study MeCP2 isoform-specific functions in vitro, and are effective gene therapy vectors for rescuing dendritic maturation of neurons in an ex vivo model of RTT