952 research outputs found
Strichartz estimates for the Schr\"odinger equation on polygonal domains
We prove Strichartz estimates with a loss of derivatives for the
Schr\"odinger equation on polygonal domains with either Dirichlet or Neumann
homogeneous boundary conditions. Using a standard doubling procedure, estimates
the on polygon follow from those on Euclidean surfaces with conical
singularities. We develop a Littlewood-Paley squarefunction estimate with
respect to the spectrum of the Laplacian on these spaces. This allows us to
reduce matters to proving estimates at each frequency scale. The problem can be
localized in space provided the time intervals are sufficiently small.
Strichartz estimates then follow from a result of the second author regarding
the Schr\"odinger equation on the Euclidean cone.Comment: 12 page
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Holmes Tremor due to Artery of Percheron Infarct: Clinical Case and Treatment Using Deep Brain Stimulation of the Vim and ZI Targets
Background: Holmes tremor (HT) arises from disruption of the cerebellothalamocortical pathways. A lesion can interrupt the projection at any point, resulting in this tremor. We describe a case of HT due to the rare artery of Percheron infarct and its successful treatment using deep brain stimulation.
Case report: A 62-year-old woman with a right medial cerebral peduncle and bilateral thalamic stroke developed HT. Ventral intermediate nucleus (Vim) zona incerta (ZI) deep brain stimulation (DBS) surgery was performed, with improvement in her tremor.
Discussion: Our case supports the theory that the more caudal ZI target in combination with Vim is beneficial in treating poorly DBS-responsive tremors such as HT
Content uniformity of quartered hydrocortisone tablets in comparison with mini-tablets for paediatric dosing
Objectives Children requiring cortisol replacement therapy are often prescribed hydrocortisone doses of 2.5 mg, but as this is commercially unavailable 10 mg tablets, with functional break lines, are split commonly in an attempt to deliver the correct dose. This study aimed to determine the dose variation obtained from quartered hydrocortisone tablets when different operators performed the splitting procedure and to ascertain whether better uniformity could be attained from mini-tablets as an alternative formulation.
Methods Hydrocortisone 10 mg tablets were quartered by four different operators using a standard pill splitter. Hydrocortisone 2.5 mg mini-tablets (3 mm diameter) were formulated using a wet granulation method and manufactured using a high-speed rotary press simulator. The weight and content uniformity of the quartered tablets and mini-tablets were assessed according to pharmacopoeial standards. The physical strength and dissolution profiles of the mini-tablets were also determined.
Results More than half of all quartered 10 mg tablets were outside of the ±10% of the stated US Pharmacopoeia hydrocortisone content (mean 2.34 mg, SD 0.36, coefficient of variation (CV) 15.18%) and more than 40% of the quartered tablets were outside the European Pharmacopoeia weight variation. Robust mini-tablets (tensile strengths of >4 MPa) were produced successfully. The mini-tablets passed the pharmacopoeial weight and content uniformity requirements (mean 2.54 mg, SD 0.04, CV 1.72%) and drug release criteria during in vitro dissolution testing.
Conclusion This study confirmed that quartering 10 mg hydrocortisone tablets produces unacceptable dose variations and that it is feasible to produce 3 mm minitablets containing more accurate doses for paediatric patients
Cardiorespiratory fitness, adiposity and incident asthma in adults
Available large-scale prospective studies on adiposity and asthma used body mass index as an
indicator of adiposity.
Studies involving more accurate measures of adiposity, such as body
fat percentage (BF%), are needed to confirm or contrast body mass index - related results.
Cardiorepiratory fitness is a strong predictor of morbidity and mortality,
and the available
literature suggests that moderate-high cardiorespiratory fitness reduces many of the health
hazards associated with obesity.
The present study aimed: 1) to examine whether
cardiorespiratory fitness and/or BF% are associated with subsequent acquisition of asthma in
adults; and 2) to test the hypothesis that a high cardiorespiratory fitness level can reduce the
risk of incident asthma in individuals with excess adiposity
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Essential tremor associated with pathologic changes in the cerebellum
Background: Although essential tremor (ET) is one of the most common neurologic disorders, there have been few postmortem studies. We recently reported postmortem changes (torpedoes and Bergmann gliosis) in the cerebellar cortex in a few ET cases. Objective: To describe more extensive postmortem changes in the cerebellum in another ET case. Design: Case report. Results: A 90-year-old woman had a 30-year history of ET. At postmortem examination, there was segmental loss of Purkinje cells, presence of torpedoes, and Bergmann gliosis in the cerebellar cortex. Moreover, there were extensive changes in the dentate nucleus, in the form of neuronal loss, neuronal atrophy, microglial clusters, and reduction in the number of efferent fibers (ie, pallor of the hilum). Conclusions: The brain in the current case exhibited more marked cerebellar pathologic features than noted in previously reported ET cases and thereby extends the described cerebellar findings in this common, yet pathologically poorly characterized, neurologic disorder
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Biobehavioral effects of Tai Chi Qigong in men with prostate cancer: Study design of a three-arm randomized clinical trial.
Fatigue is often one of the most commonly reported symptoms in prostate cancer survivors, but it is also one of the least understood cancer-related symptoms. Fatigue is associated with psychological distress, disruptions in sleep quality, and impairments in health-related quality of life. Moreover, inflammatory processes and changes related to the hypothalamic-pituitary-adrenal (HPA) axis and/or autonomic nervous system may also play a role in cancer-related fatigue. Thus, effective treatments for fatigue in prostate cancer survivors represent a current unmet need. Prior research has shown that Tai Chi Qigong, a mind-body exercise intervention, can improve physical and emotional health. Herein, we describe the protocol of the ongoing 3-arm randomized controlled Health Empowerment & Recovery Outcomes (HERO) clincal trial. One hundred sixty-six prostate cancer survivors with fatigue are randomized to a modified Tai Chi Qigong intervention (TCQ), intensity-matched body training intervention (BT), or usual care (UC) condition. Guided by biopsychosocial and psychoneuroimmunology models, we propose that TCQ, as compared to BT or UC will: i) reduce fatigue (primary outcome) in prostate cancer survivors; ii) reduce inflammation; and iii) regulate the expression of genes from two major functional clusters: a) inflammation, vasodilation and metabolite sensing and b) energy and adrenergic activation. Assessments are conducted at baseline, the 6-week midpoint of the intervention, and 1 week, 3 months, and 12 months post-intervention. If our findings show that TCQ promotes recovery from prostate cancer and its treatment, this type of intervention can be integrated into survivorship care plans as the standard of care. The study's findings will also provide novel information about underlying biobehavioral mechanisms of cancer-related fatigue. Trial registration number:NCT03326713; clinicaltrials.gov
Parents’ views on how health professionals should work with them now to get the best for their child in the future
Background  Pregnancy and the first years of life are important times for future child well-being. Early identification of families and children who might be likely to experience poorer outcomes could enable health professionals and parents to work together to promote each child’s well-being. Little is known about the acceptability and feasibility of such an approach to parents.
Objective  To investigate parents’ views about how health professionals should identify and work with families who may benefit from additional input to maximize their children’s future health and well-being.
Design  A qualitative study using focus groups.
Setting and participants  Eleven focus groups were conducted with a total of 54 parents; 42 mothers and 12 fathers living in the north of England.
Results  Parents welcomed the idea of preventive services. They strongly believed that everyone should have access to services to enhance child well-being whilst recognizing that some families need additional support. Making judgements about who should receive additional services based on specific criteria evoked powerful emotions because of the implication of failure. Parents projected a belief in themselves as ‘good parents’ even in adverse circumstances.
Conclusions  Targeted additional preventive services can be acceptable and welcome if health professionals introduce them sensitively, in the context of an existing relationship, providing parents are active participants
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