270 research outputs found

    Recursive strategy for decomposing Betti tables of complete intersections

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    We introduce a recursive decomposition algorithm for the Betti diagram of a complete intersection using the diagram of a complete intersection defined by a subset of the original generators. This alternative algorithm is the main tool that we use to investigate stability and compatibility of the Boij-Soederberg decompositions of related diagrams; indeed, when the biggest generating degree is sufficiently large, the alternative algorithm produces the Boij-Soederberg decomposition. We also provide a detailed analysis of the Boij-Soederberg decomposition for Betti diagrams of codimension four complete intersections where the largest generating degree satisfies the size condition

    Rotational energy dispersions for van der Waals molecular clusters: Analytic descriptions for Rg3, Rg4, and Rg6

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    We have obtained analytic expressions, parametric in centrifugal displacement coordinates, which provide exact classical descriptions of the rotational energy dispersions, that is, the dependence of the combined rotational and ‘‘electronic’’ (vibrational potential) energies on the rotational angular momenta, for small molecular clusters bound by van der Waals interactions modeled by pairwise additive Lennard‐Jones 6–12 potential energies. The clusters considered consist of three (equilateral triangle), four (tetrahedron), and six (octahedron) units and serve as models for small clusters of rare‐gas atoms such as argon. This work represents an extension of our recently published study of analytic rotational energy dispersions for diatomic molecules bound by harmonic oscillator, Morse, or Lennard‐Jones potentials [J. Mol. Spectrosc. 155, 205 (1992)]. A parallel set of studies were made using an angular momentum‐conserving simulation program. The physical properties of the clusters that are addressed using our results include calculation of quartic and higher‐order spectroscopic constants, location of rotational instabilities, and characterization of the ‘‘cubic’’ anisotropies for the spherical top clusters A4 and A6. Of particular interest is the result that for each of these cluster types the preferred direction of the rotational angular momentum is parallel to a molecular fourfold axis, leading to reduced symmetries of D2d for tetrahedral A4 and D4h for octahedral A6.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70411/2/JCPSA6-99-9-6369-1.pd

    A Tandem Conjugate Addition–Intramolecular Horner–Wadsworth–Emmons Olefination Approach to the Synthesis of Cyclopentene[c]chroman-2-ones and Cyclopent-1-enecarboxylates

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    A strategically new approach to cyclopentene[c]chroman- 2-ones and cyclopent-1-enecarboxylates by tandem Michael– Horner–Wadsworth–Emmons reaction of 2,5-hexanedione with 3-(diethoxyphosphoryl)coumarins is described. The products were obtained as single diastereoisomers in high yields

    Variability of Gait is Dependent on Direction of Progression: Implications for Active Control

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    Typical healthy walking displays greater variability in the mediolateral direction compared to the anteroposterior direction. This greater variability is thought to represent increased uncertainty in movement. As a result, it has been postulated that the mediolateral direction of gait requires more active control by the central nervous system while the anteroposterior direction is controlled through passive actions. However, this theory has only been tested on gait where progression occurs in the anteroposterior direction. Therefore, the purpose of this study was to investigate how the amount of variability is affected if progression occurs in the mediolateral direction using a lateral stepping gait. Results showed the anteroposterior direction had a significantly greater amount of variability than the mediolateral direction (p\u3c0.001). The results do not support current models of a partition of active control to different anatomical planes. Rather, it seems that other physical entities involved in motion, such as momentum and inertia, are able to decrease the dependence on active control from the central nervous system. In a lateral stepping gait, such physical entities were no longer assisting in the anteroposterior direction but had a larger impact in the mediolateral direction as it was the direction of progression. As a result variability in the anteroposterior direction increased. Thus, it is possible to infer increased reliance on active control from the central nervous system in the direction orthogonal to progression

    A critical examination of the State Liability Amendment Bill (2018) and its implications for medical negligence litigation in South Africa.

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    Masters Degree. University of KwaZulu-Natal, Durban.Medical negligence litigation in South Africa is an ever-growing problem that places a great burden on public hospitals and threatens their ability to render health care services. The number and monetary value of these claims against the State have reached alarming levels. The causes of this increase in claims are multifactorial, but they appear to follow a similar global trend of increasing medical negligence litigation. While other countries have developed legislation to deal with this problem, South Africa has yet to pass legislation to solve the problem. The State Liability Amendment Bill (2018) aims to make changes that would help mitigate the financial burden arising from this litigation against the Department of Health. The Bill’s provisions appear to favour the State at the expense of compromising the rights of victims of medical negligence. These provisions include replacing lumpsum payments in favour of periodic payments and having public healthcare facilities render future medical care instead of awarding monetary damages. So far, the State Liability Bill has not been kindly received by various legal commentators, and it is unlikely to withstand the inevitable constitutional scrutiny it will face if passed. The recent Constitutional Court ruling in Member of the Executive Council for Health, Gauteng Provincial Government v PN obo EN (Member of the Executive Council for Health, KwaZulu-Natal Provincial Government and other as Amici Curiae) [2021] JOL 49995 (CC) will allow for greater use of the Public Healthcare Defence and Undertaking to Pay Defence which will help lessen the financial impact of successful claims against the Department of Health. This will allow the State more time to give greater thought and consideration into making the State Liability Amendment Bill a fairer proposition for all parties involved in medical negligence litigation

    Health technology assessment for digital health technologies

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    Health technology assessment (HTA) frameworks used for making public funding decisions on digital health technologies (DHTs) have not been informed by large stakeholder preference studies and rarely cover all nine domains of the widely used EUnetHTA “Core Model”. Our aim was to develop a literature-informed and stakeholder-prioritised checklist of DHT-specific considerations for DHTs that manage chronic disease that extends an internationally established HTA framework. We conducted two systematic reviews to identify: (i) DHT evaluation frameworks and (ii) primary research on DHTs published until 20 March 2020. Stakeholder prioritisation of issues was performed using a best-worst preference study among a broad cross-section of patients, carers, health professionals, and the general population in Australia, Canada, New Zealand, and the UK. Systematic review issues were prioritised and adapted for use as a practical checklist. DHT evaluation content was recommended by 44 identified frameworks for 28 of the 145 issues in the Core Model and for 22 new DHT-specific issues. A coverage assessment of 112 clinical studies of remote treatment and self-management DHTs for patients with cardiovascular disease or diabetes revealed that less than half covered DHT-specific content in all but one domain, or traditional HTA content in clinical effectiveness and ethical analysis. The preference survey of 1,251 stakeholders identified broad agreement on the 12 most important DHT attributes, six of which were related to safety. The most important attribute was “helps health professionals respond quickly when changes in patient care are needed”, which is not a focus of existing DHT HTA frameworks. Using the thesis-developed checklist in conjunction with the Core Model can enable users to perform a DHT-specific and comprehensive HTA on DHTs that manage chronic disease and can assist primary researchers to collect appropriate data to inform this HTA

    Usporedba određenih hematoloških pokazatelja među trima vrstama porodice Columbidae.

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    Investigations into some haematological values in birds from three Columbidae species e.g. pigeons, (Columba livia domestica), collared doves (Streptopelia decaocto) and African collared doves, (Streptopelia roseogrisea) have been performed. In all three species, high haemoglobin concentrations, and respectively high red blood cell counts were observed. In S. decaocto the red blood cell count was extremely high, corresponding to the high haemoglobin levels. RBC values in both Streptopelia species were significantly higher than in domestic pigeons. Higher white blood cell counts were present in freely living collared doves versus both species living in captivity. The heterophils/lymphocytes ratio in African collared doves was the highest − 1.05, followed by the ratios of collared doves and domestic pigeons.Provedeno je istraživanje hematoloških vrijednosti triju vrsta ptica porodice Columbidae, i to goluba (Columba livia domestica), gugutke (Streptopelia decaocto) i sahelske gugutke (Streptopelia roseogrisea). U sve tri vrste ustanovljena je velika koncentracija hemoglobina i velik broj crvenih krvnih stanica. U gugutke je broj eritrocita bio iznimno velik, i odgovarao je velikoj razini hemoglobina. Broj eritrocita bio je u obje vrste roda Streptopelia veći nego u goluba. Veći broj bijelih krvnih stanica ustanovljen je u slobodno živućih gugutki u odnosu na one držane u zatočeništvu. Omjer heterofila i limfocita u sahelske gugutke bio je najveći (1,05), srednji u gugutke, a najmanji u goluba

    An unstable shoe with a rocker bottom redistributes external work

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    The purpose of this study was to examine the external work performed by individuals wearing a rocker bottom shoe compared to a standard shoe. It was hypothesized that individuals wearing a rocker bottom shoe would have changes in the amount of work over the course of contact with the ground. External work on the body’s centre of mass (BCOM) was calculated for individuals in both conditions. Comparisons for external work were done for positive and negative work for the entire stance phase as well as the initial double support, single support and terminal double support periods. The results revealed that while wearing the rocker bottom shoes, individuals performed an increased amount of negative work and decreased positive work in the initial double support followed by increased positive work in single support compared to a standard sole shoe. Individuals also performed a decreased amount of positive and negative work in terminal double support when wearing the rocker bottom shoes. There were no differences, however, when the stance phase was considered undivided to subphases for either positive or negative work. The results indicate that use of rocker bottom shoes redistributes external work to earlier in the gait cycle, which may not be as energetically efficient. This shift will probably result in increased metabolic energy expenditure as it will require more energy output from proximal hip musculature, which is not as mechanically efficient as the ankle joint in late stance. This could be desirable for individuals who are wearing the shoes for increased caloric burn such as an exercise setting. Furthermore, the increased external work in single support may be causing additional work from the hip extensor musculature (i.e. gluteus maximus). This could possibly be desirable for strengthening and conditioning of the hip extensors
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