Seymour's second neighborhood conjecture for tournaments missing a generalized star

Seymour's Second Neighborhood Conjecture asserts that every digraph (without digons) has a vertex whose first out-neighborhood is at most as large as its second out-neighborhood. We prove its weighted version for tournaments missing a generalized star. As a consequence the weighted version holds for tournaments missing a sun, star, or a complete graph.Comment: Accepted for publication in Journal of Graph Theory in 24 June 201

Ceftriaxone-induced toxic epidermal necrolysis mimicking burn injury: a case report

<p>Abstract</p> <p>Introduction</p> <p>Toxic epidermal necrolysis is a rare exfoliative disorder with a high mortality rate.</p> <p>Case presentation</p> <p>We present a 70-year-old woman of Iranian descent who presented with toxic epidermal necrolysis that was initially diagnosed as a scald burn. Further anamnesis prompted by spread of the lesions during hospitalization revealed that the patient had been receiving ceftriaxone for several days. To the best of our knowledge, this is the first case of ceftriaxone-induced toxic epidermal necrolysis in the English literature.</p> <p>Conclusion</p> <p>Toxic epidermal necrolysis is an acute, life-threatening, exfoliative disorder with a high mortality rate. High clinical suspicion, prompt recognition, and initiation of supportive care is mandatory. Thorough investigation of the pathogenetic mechanisms is fundamental. Optimal treatment guidelines are still unavailable.</p

Springback analysis of AA5754 after hot stamping: experiments and FE modelling

In this paper, the springback of the aluminium alloy AA5754 under hot stamping conditions was characterised under stretch and pure bending conditions. It was found that elevated temperature stamping was beneficial for springback reduction, particularly when using hot dies. Using cold dies, the flange springback angle decreased by 9.7 % when the blank temperature was increased from 20 to 450 °C, compared to the 44.1 % springback reduction when hot dies were used. Various other forming conditions were also tested, the results of which were used to verify finite element (FE) simulations of the processes in order to consolidate the knowledge of springback. By analysing the tangential stress distributions along the formed part in the FE models, it was found that the springback angle is a linear function of the average through-thickness stress gradient, regardless of the forming conditions used

Synthesis and reactions of novel thienotetrahydroisoquinoline compounds

Chloroacetylation of 1-Aminocarboxamide 1 afforded the chloroacetylamino 2 which underwent ring closure upon reflux with acetic anhydride to afford the chloromethylpyrimido 3. The latter compounds under went nucleophilic substitution reactions with various primary and secondary amines which underwent Mannich reaction to give theimidazopyrimidothienoisoquinolines 5a-c. Compound 1 react with phthalic an hydride in acetic acid and DMF to afford phthalimido and isoindolopyrimido thienotetrahydroisoquinoline 6, 7 respectively. Reaction with diethylmalonate afforded the pyrimidocarboxylate 8 which react with hydrazine hydrate to give the carbohydrazide 9 which react with triethyl orthoformate for synthesis of triazepinopyrimido 10. Reaction of 1 with carbon disulfide in pyridine afforded the pyrimidinethione 13 which underwent double Mannich reaction to give the novel thiadiazinopyrimido compound 14. Reaction of tetrahydroisoquinolinethione 15 with 2-chloromethylbenzimidazole followed by Thorpe-Zeigler cyclization to afford the aminobenzoimidazolyl 18 which proved its versatility as starting material for synthesis of novel heterocycliccompounds 19-22. Imidazole; triazepine; thiadiazine; pyrimidine; synthesis; reactions

Post-traumatic soft tissue tumors: Case report and review of the literature a propos a Post-traumatic paraspinal desmoid tumor

<p>Abstract</p> <p>Background</p> <p>Antecedent trauma has been implicated in the causation of soft tissue tumors. Several criteria have been established to define a cause-and-effect relationship. We postulate possible mechanisms in the genesis of soft tissue tumors following antecedent traumatic injury.</p> <p>Case presentation</p> <p>We present a 27-year-old woman with a paraspinal desmoid tumor, diagnosed 3-years following a motor vehicle accident. Literature is reviewed.</p> <p>Conclusion</p> <p>Soft tissue tumors arising at the site of previous trauma may be desmoids, pseudolipomas or rarely, other soft tissue growths. The cause-and-effect issue of desmoid or other soft tissue tumors goes beyond their diagnosis and treatment. Surgeons should be acquainted with this diagnostic entity as it may also involve questions of longer follow-up and compensation and disability privileges.</p

Re-thinking flexibility in higher education: A shared responsibility of students and educators

In recent years, there has been a growing recognition of the importance of flexibility in higher education as a key factor that can contribute to enhancing student learning and accessibility. However, flexibility has previously been investigated through an institutional lens that fails to consider those directly involved—students and educators. Moreover, the majority of current research regarding flexibility is based on anecdotal evidence and theoretical frameworks; therefore, evidence-based research is lacking. This plenary session is presented from a student perspective, who found that often, the parts of her identity that she took pride in—middle eastern background, gender, and hearing loss—were also the cause of her struggles. In conversations with other students, it was revealed that their diversity or life circumstances hindered their ability to pursue education. Flexibility was identified as key to enhancing their academic experience. Thus, the presenter decided to focus her fourth year thesis on a project that investigated students’ and educators’ experiences surrounding flexibility to inform future policies about effective flexible practices that accurately represent both groups. This session will highlight similarities and differences between students’ and educators’ experiences, barriers educators face when implementing flexibility, and a current misalignment in perceptions of flexibility between students and educators. Engaging in transparent and reciprocal open conversations can enhance the student-educator bond and solidify both groups’ sense of belonging. This study was approved by Western’s Non-Medical Research Ethics Board

Monitoring coronary blood flow by laser speckle contrast imaging after myocardial ischaemia reperfusion injury in adult and aged mice

Introduction: Investigating coronary microvascular perfusion responses after myocardial infarction (MI) would aid in the development of flow preserving therapies. Laser speckle contrast imaging (LSCI) is a powerful tool used for real-time, non-contact, full-field imaging of blood flow in various tissues/organs. However, its use in the beating heart has been limited due to motion artifacts. Methods: In this paper, we report the novel use of LSCI, combined with custom speckle analysis software (SpAn), to visualise and quantitate changes in ventricular perfusion in adult and aged mice undergoing ischaemia-reperfusion (IR) injury. The therapeutic benefit of inhibiting the actions of the pro-inflammatory cytokine interleukin-36 (IL-36) was also investigated using an IL-36 receptor antagonist (IL-36Ra). Results: Imaging from uncovered and covered regions of the left ventricle demonstrated that whilst part of the LSCI flux signal was derived from beating motion, a significant contributor to the flux signal came from ventricular microcirculatory blood flow. We show that a biphasic flux profile corresponding to diastolic and systolic phases of the cardiac cycle can be detected without mathematically processing the total flux data to denoise motion artifacts. Furthermore, perfusion responses to ischaemia and postischaemia were strong, reproducible and could easily be detected without the need to subtract motion-related flux signals. LSCI also identified significantly poorer ventricular perfusion in injured aged mice following IR injury which markedly improved with IL-36Ra. Discussion: We therefore propose that LSCI of the heart is possible despite motion artifacts and may facilitate future investigations into the role of the coronary microcirculation in cardiovascular diseases and development of novel therapies

SYNTHESIS AND REACTIONS OF SOME NEW MORPHOLINYLPYRROLYL TETRAHYDROTHIENO[2,3-c] ISOQUINOLINE

&nbsp;Hydrazinolysis of ethyl-5-morpholin-4-yl-1-(1H-pyrrol-1-yl)-6,7,8,9-tetrahydrothieno[2,3-c]iso- quinoline-2-carboxylate &nbsp;afforded the corresponding carbo- hydrazide which upon condensation with aromatic aldehydes, acetyl acetone and/ or carbon disulfide gave N- arylidinecarbohydrazide, dimethylpyrazolyl methanone, [1,3,4]oxadiazole-2-thiol and its ethyl ester derivatives respectively. Diazotization of the carbohydrazide with nitrous acid afforded the corresponding carboazide which was used for synthesis of carbamates and substituted carboxamides. Boiling of the carboazide in dry xylene afforded the pyrazinone compound which was used for synthesis of other heterocycles containing pyrrolopyrazinothinoisoquinoline moeity

Development of a new piezoelectric pulse testing device and soil characterization using shear waves

The shear-wave velocity (Vs ) is a fundamental parameter that correlates well to soil properties, and is important in many applications. Hence, there is an increasing interest in using shear-wave velocity to define soil state (void ratio, effective stresses, density, liquefaction potential, etc).The global idea of this research is to establish correlations between shear wave velocity and the basic soil parameters that can be used to evaluate soil properties and estimate its strength and deformation characteristics. These relationships will also allow the interpretation of in situ geophysical measurements in terms of the design parameters of soil.The needed reliable correlations should be based on accurate measurements. In this research, it has been proven that the bender-elements method, which is widely used to measure shear wave velocity of soil in laboratory setups, suffers from fundamental and interpretative problems. Consequently, its results are controversial and might give highly erroneous values. After thorough numerical and laboratory investigations, a new piezoelectric pulse testing device (Ring Actuators Setup) was invented and developed in this research. This setup is composed of two units (emitter and receiver) and is capable of measuring shear and compression wave velocities of soil specimens. It is a completely new, versatile, advanced and accurate setup. With this device, many problems of pulse tests, which make interpretation of results difficult and ambiguous, were solved.The ring actuators setup overcomes wave reflections at boundaries (end-caps and sides), sample disturbance, weak shear coupling between soil and device (interaction) as well as the fixation problems, low resonant frequency and limited input voltage of the existing device.The development stages of this device were also useful in reaching important findings for building robust setups. This device was implemented in the top cap and pedestal of a large oedometer cell. This setup was also used with Proctor mold as well as other fabricated molds. Many pulse tests were carried out on different soil types using this device. Shear and compression wave velocities could be accurately measured at dry and partially saturated conditions under very low to high pressures.The compaction curves, in terms of Vs and water content, were drawn for two soil types using the new device. In addition, some correlations between Vs and soil parameters were obtained. Numerical simulations and analytical studies were also carried out in this research in order to study the characteristics of elastic waves transmission through soil specimens in different laboratory setups.The bender-elements and the ring actuators models were studied.The interpretation problems of pulse tests were thoroughly investigated numerically and experimentally. In this research, the reason of 'near-field effect' in pulse tests, which causes significant errors in the interpretation process, could be discovered.The parameters that control this phenomenon could be stated and their effects on the test results were quantified. In light of these results, a new criterion for carrying out and interpreting pulse tests was established. Also, a simple interpretation method is introduced (Energy Rise-Time). Furthermore, the dispersive nature of pulse tests was proven numerically and experimentally. Moreover, it was concluded that the shear wave velocity from pulse tests should be interpreted in the frequency domain, which renders 'the simple methods of interpretation' inaccurate. Based on these findings, a new interpretation technique for pulse tests using Wigner-Ville transform was presented. It was successfully used to interpret the numerical and physical pulse test results in this study.The last part of this research concerns soil characterization using shear wave velocity. Establishing correlations between Vs and soil parameters that can be used for soil characterization may be achieved in laboratory using piezoelectric devices, as mentioned above, or by deriving relationships between Vs and in situ test indices. In this research, the second approach was also examined for gravelly sands. Results of the comprehensive field testing program for the natural soil and the embankment materials (fill) at Péribonka dam site were used to achieve this goal. Thorough interpretations and analyses were carried out for these tests in order to derive correlations between each of CPTu and SPT indices and the in-situ Vs -measurements. Several important relationships and conclusions for soil characterization using shear waves could be reached. These correlations are useful for soil characterization not only at this site, but at other sites of similar soil composition

Understanding Social Workers\u27 Roles Providing Case Management to Medicaid Managed Care Enrollees

Social workers often take on the role of providing case management to Medicaid recipients; however, there is little clinical research on social workers\u27 perceptions of their case management role. The purpose of this study was to develop an understanding of the social worker case management role by exploring social workers\u27 perceptions of their roles when providing case management to Ohio Medicaid managed care enrollees. This action research study was grounded in organizational role theory. A semi structured focus group was facilitated using open-ended questions related to social workers\u27 role perceptions, role conflict, role ambiguity, case management, and managed care. Qualitative data were collected from 5 licensed Ohio social workers working as case managers with clients enrolled in an Ohio Medicaid managed care plan. The data were coded and analyzed using constant comparison analysis to identify relevant themes. Four themes emerged from the data: care coordination, role conflict and ambiguity, lack of social work influence in managed care, and resources. The findings of the study may serve as a step toward filling gaps in the understanding of the role of social workers who provide case management services to Ohio\u27s Medicaid managed care enrollees. The findings may also be used to effect positive social change by increasing stakeholders\u27 understanding of social workers\u27 roles in case management and encouraging stakeholders to take steps to identify and address possible role conflict and ambiguity