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"Education of Children with Disabilities: Voices from Around the World" combines research on children with disabilities and women/girls with disabilities. These projects provided opportunities to interview disability professionals, policy-makers and persons with disabilities from around the world with the purpose of learning about needs, issues and services, in diverse countries. A unique international analysis, this research compares various cultural responses on the education of children with disabilities emphasizing the girl child. Discussion includes findings based on 177 interviews of disability professionals from over 57 countries including the stated reasons and consequences of lost educational opportunities. Techniques locating participants included internet searches, literature reviews, and personal referrals. Interviewees were selected based on their experiences with childhood disabilities and/or women and girls with disabilities. Many interviewees were persons with disabilities who shared their personal experiences. Through a qualitative analysis of the interviews some of the most prevalent themes that emerged were the importance of education and the disproportionate negative effect of disability on females. To measure the strength of these themes, an electronic survey was created using a Likert scale to measure the strength of agreement of each participant with the issues identified. Survey ratings added quantitative confirmation to the rich qualitative interviews. The education themes identified include school exclusion and barriers to education with a particular focus on the girl child, education quality and inclusive education.

Males of some species, from horses to humans, require medical help for subfertility problems. There is an urgent need for novel molecular assays that reflect spermatozoal function. In the last 25 years, studies examined RNAs in spermatozoa as a window into gene expression during their development and, more recently, for their functions in early embryo development. In clinics, more dense spermatozoa are isolated by density gradient centrifugation before use in artificial insemination to increase pregnancy rates. The objectives of the current study were to discover and quantify the microRNAs in stallion spermatozoa and identify those with differential expression levels in more dense versus less dense spermatozoa. First, spermatozoa from seven stallions were separated into more dense and less dense populations by density gradient centrifugation. Next, small RNAs were sequenced from each of the 14 RNA samples. We identified 287 different mature microRNAs within the 11,824,720 total mature miRNA reads from stallion spermatozoa. The most prevalent was miR‐10a/b‐5p. The less dense spermatozoa had fewer mature microRNAs and more microRNA precursor sequences than more dense spermatozoa, perhaps indicating that less dense spermatozoa are less mature. Two of the most prevalent microRNAs in more dense stallion spermatozoa were predicted to target mRNAs that encode proteins that accelerate mRNA decay. Nine microRNAs were more highly expressed in more dense spermatozoa. Three of those microRNAs were predicted to target mRNAs that encode proteins involved in protein decay. Both mRNA and protein decay are very active in late spermiogenesis but not in mature spermatozoa. The identified microRNAs may be part of the mechanism to shut down those processes. The microRNAs with greater expression in more dense spermatozoa may be useful biomarkers for spermatozoa with greater functional capabilities. [ABSTRACT FROM AUTHOR]

Introduction: Salvage procedures such as proximal row carpectomy, 4-corner fusion, total wrist arthroplasty, and total wrist arthrodesis are commonly used at the end stages of wrist arthritis. These operations have high complication rates, and significant controversy exists regarding the selection of procedure. Long-term oral glucocorticoid therapy has previously been identified as a risk factor for complications in multiple orthopedic procedures. The purpose of this study is to investigate the effect long-term oral preoperative corticosteroid use has on complications after different salvage operations for wrist arthritis. Methods: The National Surgical Quality Improvement Program database was queried to identify patients who underwent proximal row carpectomy, 4-corner fusion, total wrist arthroplasty, or total wrist fusion between 2005 and 2020. Patients were classified by steroid use. Univariate analysis and multivariate logistic regression were used to assess the risk of complications. Results: A total of 1298 patients were identified. Overall, steroid use was found to be independently associated with a higher complication rate. On multivariate analysis of patients who underwent 4-corner fusion, steroid use was found to be associated with higher complication rate and surgical site infection rate. Steroid use was not associated with increased complications in patients who underwent proximal row carpectomy, total wrist arthroplasty, or total wrist fusion when examined individually. Conclusion: Long-term oral corticosteroid therapy was associated with an increased risk of postoperative infections in patients who underwent 4-corner fusion, which was not found in other wrist salvage operations. [ABSTRACT FROM AUTHOR]

Insect crop pests threaten global food security. This threat is amplified through the spread of nonnative species and through adaptation of native pests to control measures. Adaptations such as pesticide resistance can result from selection on variation within a population, or through gene flow from another population. We investigate these processes in an economically important noctuid crop pest, Helicoverpa zea , which has evolved resistance to a wide range of pesticides. Its sister species Helicoverpa armigera , first detected as an invasive species in Brazil in 2013, introduced the pyrethroid-resistance gene CYP337B3 to South American H. zea via adaptive introgression. To understand whether this could contribute to pesticide resistance in North America, we sequenced 237 H. zea genomes across 10 sample sites. We report H. armigera introgression into the North American H. zea population. Two individuals sampled in Texas in 2019 carry H. armigera haplotypes in a 4 Mbp region containing CYP337B3. Next, we identify signatures of selection in the panmictic population of nonadmixed H. zea , identifying a selective sweep at a second cytochrome P450 gene: CYP333B3. We estimate that its derived allele conferred a ∼5% fitness advantage and show that this estimate explains independently observed rare nonsynonymous CYP333B3 mutations approaching fixation over a ∼20-year period. We also detect putative signatures of selection at a kinesin gene associated with Bt resistance. Overall, we document two mechanisms of rapid adaptation: the introduction of fitness-enhancing alleles through interspecific introgression, and selection on intraspecific variation. [ABSTRACT FROM AUTHOR]

We investigate the converse of the known fact that if the Gershgorin discs of a real n-by-n matrix may be separated by positive diagonal similarity, then the eigenvalues are real. In the 2-by-2 case, with appropriate signs for the off-diagonal entries, we find that the converse is correct, which raises several questions. First, in the 3-by-3 case, the converse is not generally correct, but, empirically, it is frequently true. Then, in the n-by-n case, $ n\ge 3 $ n ≥ 3 , we find that if all the 2-by-2 principal submatrices have inseparable discs ('strongly inseparable discs'), the full matrix must have a nontrivial pair of conjugate complex eigenvalues (i.e. cannot have all real eigenvalues). This hypothesis cannot generally be weakened. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to identify demographic data, medical comorbidities, and perioperative factors that are associated with increased risk of overall surgical complications, wound complications, and reoperation within 30 days of open reduction and internal fixation (ORIF) of distal radius fractures. Methods: All adult patients undergoing ORIF of distal radius fractures in the National Surgical Quality Improvement Program database between 2005 and 2020 were identified. Patients were excluded for secondary procedures, open/infected injuries, or inpatient surgical setting. Demographic data, medical comorbidities, and perioperative data were examined for each patient, and patients were grouped by the presence or absence of any surgical complication. Univariate analysis and multivariate logistic regression were used to identify risk factors. Results: A total of 20 301 patients from between 2005 and 2020 met the inclusion criteria, of which 219 complications (1.1% of cases) were identified. Following multivariate analysis, independent risk factors found to be associated with surgical complications included male sex, smoking, heart failure, longer operative time, and American Society of Anesthesiologists (ASA) classification of 3 or higher. Conclusion: Male sex, smoking, heart failure, prolonged operative time, and ASA status of 3 or higher are associated with an increased risk of surgical complications following ORIF of distal radius fractures. These complications, with the exception of heart failure, were also associated with an increased risk of wound complications. Finally, male sex, nonwhite race, smoking, dialysis, prolonged operative time, and 3 or higher ASA class were associated with reoperations. Understanding these risk factors allows surgeons to better predict and prevent complications in high-risk populations. [ABSTRACT FROM AUTHOR]

Using the recent geometric Parter-Wiener, etc. theorem and related results, it is shown that much of the multiplicity theory developed for real symmetric matrices associated with paths and generalized stars remains valid for combinatorially symmetric matrices over a field. A characterization of generalized stars in the case of combinatorially symmetric matrices is given.

It is shown that in any TP matrix, a line (row or column) with two speci˝ed entries in any positions (and the others appropriately chosen) may be inserted in any position, as long as the two entries are consistent with total positivity. This generalizes an unconstrained result previously proven, and the two may not generally be increased to three or more. Applications are given, and this fact should be useful in other completion problems, as the unconstrained result has been.

We report experimental studies to understand the reaction mechanism of the intermetallic anode Cu2Sb with Na and demonstrate that it is capable of retaining about 250 mAh g-1 over 200 cycles when using fluoroethylene carbonate additive. X-ray diffraction data indicate during the first discharge the reaction leads to the formation of crystalline Na 3Sb via an intermediate amorphous phase. Upon desodiation the Na 3Sb reverts to an amorphous phase, which then recrystallizes into Cu2Sb at full charge, indicating a high degree of structural reversibility. The structure after charging to 1 V is different from that of Cu2Sb, as indicated by X-ray absorption spectroscopy and 121Sb Mössbauer spectroscopy, and is due to the formation of an amorphous Na-Cu-Sb phase. At full discharge, an isomer shift of -8.10 mm s -1 is measured, which is close to that of a Na3Sb reference powder (-7.95 mm s-1) and in agreement with the formation of Na3Sb domains. During charge, the isomer shift at 1 V (-9.29 mm s-1) is closer to that of the pristine material (-9.67 mm s -1), but the lower value is consistent with the lack of full desodiation, as expected from the potential profile and the XAS data. © 2014 American Chemical Society.

Vertices in the graph of a square matrix over a field may be classified as to how their removal changes the geometric multiplicity of an identified eigenvalue. There are three possibilities: $ +1 $ + 1 (Parter); no change (neutral); and $ -1 $ − 1 (downer). When the graph is a tree, the 'downer branch mechanism' distinguishes the Parter vertices. Here, we discover how this mechanism generalizes for general graphs, both for Hermitian matrices and general matrices. Then, we apply the new ideas, both to classify pendent edges in general graphs, and to understand the existence of 2-downer edge cycles in general graphs, when there is a 2-downer edge. This is a further explanation of why such edges cannot occur in trees. [ABSTRACT FROM AUTHOR]

Loss of tail rotor effectiveness (LTE), also known as unanticipated yaw, has been recognized to be a major contributing factor in several helicopter accidents due to the loss of directional control. Flight tests have identified specific wind azimuth regions that may alter the angle and the speed of the airflow through the tail rotor leading to LTE. Through the helicopter flight data monitoring (HFDM) program, pilots receive constant flight evaluation reports to support LTE risk mitigation. Nevertheless, the existing LTE safety metric presents several pitfalls that hinder the reliability of the detection of violations of boundaries for flight safety. To identify the appropriate methods to properly simulate and flag LTE events and develop a more comprehensive and reliable LTE safety metric to be used within the HFDM environment, a physics-based investigation of the different LTE flight characteristics is performed. The results from this investigation are expected to contribute towards an improvement in detection of LTE events, leading to a reduction in LTE-related accidents. [ABSTRACT FROM AUTHOR]