Brane Localization and Stabilization via Regional Physics

Extra-dimensional scenarios have become widespread among particle and gravitational theories of physics to address several outstanding problems, including cosmic acceleration, the weak hierarchy problem, and the quantization of gravity. In general, the topology and geometry of the full spacetime manifold will be non-trivial, even if our ordinary dimensions have the topology of their covering space. Most compact manifolds are inhomogeneous, even if they admit a homogeneous geometry, and it will be physically relevant where in the extra-dimensions one is located. In this letter, we explore the use of both local and global effects in a braneworld scenario to naturally provide position-dependent forces that determine and stabilize the location of a single brane. For illustrative purposes, we consider the 2-dimensional hyperbolic horn and the Euclidean cone as toy models of the extra-dimensional manifold, and add a brane wrapped around one of the two spatial dimensions. We calculate the total energy due to brane tension and bending (extrinsic curvature) as well as that due to the Casimir energy of a bulk scalar satisfying a Dirchlet boundary condition on the brane. From the competition of at least two of these effects there can exist a stable minimum of the effective potential for the brane location. However, on more generic spaces (on which more symmetries are broken) any one of these effects may be sufficient to stabilize the brane. We discuss this as an example of physics that is neither local nor global, but regional.Comment: 4 pages, 2 figures. PRL submitte

Clipless management of the renal vein during hand-assist laparoscopic donor nephrectomy

BACKGROUND: Laparoscopic live donor nephrectomy has become the preferred method of donor nephrectomy at many transplant centers. The laparoscopic stapling device is commonly used for division of the renal vessels. Malfunction of the stapling device can occur, and is often due to interference from previously placed clips. We report our experience with a clipless technique in which no vascular clips are placed on tributaries of the renal vein at or near the renal hilum in order to avoid laparoscopic stapling device misfires. METHODS: From December 20, 2002 to April 12, 2005, 50 patients underwent hand-assisted laparoscopic left donor nephrectomy (LDN) at our institution. Clipless management of the renal vein tributaries was used in all patients, and these vessels were divided using either a laparoscopic stapling device or the LigaSureTM device (Valleylab, Boulder, CO). The medical and operative records of the donors and recipients were reviewed to evaluate patient outcomes. RESULTS: The mean follow-up time was 14 months. Of the 50 LDN procedures, there were no laparoscopic stapling device malfunctions and no vascular complications. All renal allografts were functioning at the time of follow-up. CONCLUSION: Laparoscopic stapling device failure due to deployment across previously placed surgical clips during laparoscopic live donor nephrectomy can be prevented by not placing clips on the tributaries of the renal vein. In our series, there were no vascular complications and no device misfires. We believe this clipless technique improves the safety of laparoscopic donor nephrectomy

Paramedic Differentiation of Asthma and COPD in the Prehospital Setting Is Difficult

Introduction. Separate clinical practice guidelines (CPG) for asthma and chronic obstructive pulmonary disease (COPD) often guide prehospital care. However, having distinct CPGs implies that paramedics can accurately differentiate these conditions. We compared the accuracy of paramedic identification of these two conditions against the emergency department (ED) discharge diagnosis. Methods. A retrospective cohort of all patients transported to ED by ambulance in Perth, Western Australia between July 2012 and June 2013; and identified as “asthma” or “COPD” by paramedics. We linked ambulance data to emergency department discharge diagnosis. Results. Of 1,067 patients identified by paramedics as having asthma, 41% had an ED discharge diagnosis of asthma, i.e., positive predictive value (PPV) = 41% (95% CI 38–44%). Of 1,048 patients recorded as COPD, 57% had an ED discharge diagnosis of COPD (PPV 57%; 95% CI 54–60%). Sensitivity for the paramedic identification of patients diagnosed with asthma or COPD in the ED was 66% for asthma (95% CI 63–70%) and 39% for COPD (95% CI 36–41%). Paramedics reported wheezing in 86% of asthma and 55% of COPD patients. Conclusion. Differentiating between asthma and COPD in the prehospital setting is difficult. A single CPG for respiratory distress would be more useful for the clinical management of these patients by paramedics

Molecular details of quinolone–DNA interactions: solution structure of an unusually stable DNA duplex with covalently linked nalidixic acid residues and non-covalent complexes derived from it

Quinolones are antibacterial drugs that are thought to bind preferentially to disturbed regions of DNA. They do not fall into the classical categories of intercalators, groove binders or electrostatic binders to the backbone. We solved the 3D structure of the DNA duplex (ACGCGU-NA)(2), where NA denotes a nalidixic acid residue covalently linked to the 2′-position of 2′-amino-2′-deoxyuridine, by NMR and restrained torsion angle molecular dynamics (MD). In the complex, the quinolones stack on G:C base pairs of the core tetramer and disrupt the terminal A:U base pair. The displaced dA residues can stack on the quinolones, while the uracil rings bind in the minor groove. The duplex-bridging interactions of the drugs and the contacts of the displaced nucleotides explain the high UV-melting temperature for d(ACGCGU-NA)(2) of up to 53°C. Further, non-covalently linked complexes between quinolones and DNA of the sequence ACGCGT can be generated via MD using constraints obtained for d(ACGCGU-NA)(2). This is demonstrated for unconjugated nalidixic acid and its 6-fluoro derivative. The well-ordered and tightly packed structures thus obtained are compatible with a published model for the quinolone–DNA complex in the active site of gyrases

Aging affects attunement in perceiving length by dynamic touch

Earlier studies have revealed age-dependent differences in perception by dynamic touch. In the present study, we examined whether the capacity to learn deteriorates with aging. Adopting an ecological approach to learning, the authors examined the process of attunement—that is, the changes in what informational variable is exploited. Young and elderly adults were trained to perceive the lengths of unseen, handheld rods. It was found that the capacity to attune declines with aging: Contrary to the young adults, the elderly proved unsuccessful in learning to detect the specifying informational variables. The fact that aging affects the capacity to attune sets a new line of research in the study of perception and perceptual-motor skills of elderly. The authors discuss the implications of their findings for the ongoing discussions on the ecological approach to learning

Skin prick testing in patients using beta-blockers: a retrospective analysis

<p>Abstract</p> <p>Rationale</p> <p>The use of beta-blockers is a relative contraindication in allergen skin testing yet there is a paucity of literature on adverse events in this circumstance. We examined a population of skin tested patients on beta-blockers to look for any adverse effects.</p> <p>Methods</p> <p>Charts from 2004-2008 in a single allergy clinic were reviewed for any patients taking a beta-blocker when skin tested. Data was examined for skin test reactivity, type of skin test, concomitant asthma diagnosis, allergens tested, and adverse events.</p> <p>Results</p> <p>One hundred and ninety-one patients were taking beta-blockers when skin testing occurred. Seventy-two patients had positive skin tests. No tests resulted in an adverse event.</p> <p>Conclusions</p> <p>This data demonstrates the relative safety of administrating of skin prick tests to patients on beta-blocker treatment. Larger prospective studies are needed to substantiate the findings of this study.</p

In-reach specialist nursing teams for residential care homes : uptake of services, impact on care provision and cost-effectiveness

Background: A joint NHS-Local Authority initiative in England designed to provide a dedicated nursing and physiotherapy in-reach team (IRT) to four residential care homes has been evaluated.The IRT supported 131 residents and maintained 15 'virtual' beds for specialist nursing in these care homes. Methods: Data captured prospectively (July 2005 to June 2007) included: numbers of referrals; reason for referral; outcome (e.g. admission to IRT bed, short-term IRT support); length of stay in IRT; prevented hospital admissions; early hospital discharges; avoided nursing home transfers; and detection of unrecognised illnesses. An economic analysis was undertaken. Results: 733 referrals were made during the 2 years (range 0.5 to 13.0 per resident per annum)resulting in a total of 6,528 visits. Two thirds of referrals aimed at maintaining the resident's independence in the care home. According to expert panel assessment, 197 hospital admissions were averted over the period; 20 early discharges facilitated; and 28 resident transfers to a nursing home prevented. Detection of previously unrecognised illnesses accounted for a high number of visits. Investment in IRT equalled £44.38 per resident per week. Savings through reduced hospital admissions, early discharges, delayed transfers to nursing homes, and identification of previously unrecognised illnesses are conservatively estimated to produce a final reduction in care cost of £6.33 per resident per week. A sensitivity analysis indicates this figure might range from a weekly overall saving of £36.90 per resident to a 'worst case' estimate of £2.70 extra expenditure per resident per week. Evaluation early in implementation may underestimate some cost-saving activities and greater savings may emerge over a longer time period. Similarly, IRT costs may reduce over time due to the potential for refinement of team without major loss in effectiveness. Conclusion: Introduction of a specialist nursing in-reach team for residential homes is at least cost neutral and, in all probability, cost saving. Further benefits include development of new skills in the care home workforce and enhanced quality of care. Residents are enabled to stay in familiar surroundings rather than unnecessarily spending time in hospital or being transferred to a higher dependency nursing home setting

Global Genotype-Phenotype Correlations in Pseudomonas aeruginosa

Once the genome sequence of an organism is obtained, attention turns from identifying genes to understanding their function, their organization and control of metabolic pathways and networks that determine its physiology. Recent technical advances in acquiring genome-wide data have led to substantial progress in identifying gene functions. However, we still do not know the function of a large number of genes and, even when a gene product has been assigned to a functional class, we cannot normally predict its contribution to the phenotypic behaviour of the cell or organism - the phenome. In this study, we assessed bacterial growth parameters of 4030 non-redundant PA14 transposon mutants in the pathogenic bacterium Pseudomonas aeruginosa. The genome-wide simultaneous analysis of 119 distinct growth-related phenotypes uncovered a comprehensive phenome and provided evidence that most genotypes are not phenotypically isolated but rather define specific complex phenotypic clusters of genotypes. Since phenotypic overlap was demonstrated to reflect the relatedness of genotypes on a global scale, knowledge of an organism's phenome might significantly contribute to the advancement of functional genomics

Time spent with cats is never wasted: Lessons learned from feline acromegalic cardiomyopathy, a naturally occurring animal model of the human disease

<div><p>Background</p><p>In humans, acromegaly due to a pituitary somatotrophic adenoma is a recognized cause of increased left ventricular (LV) mass. Acromegalic cardiomyopathy is incompletely understood, and represents a major cause of morbidity and mortality. We describe the clinical, echocardiographic and histopathologic features of naturally occurring feline acromegalic cardiomyopathy, an emerging disease among domestic cats.</p><p>Methods</p><p>Cats with confirmed hypersomatotropism (IGF-1>1000ng/ml and pituitary mass; n = 67) were prospectively recruited, as were two control groups: diabetics (IGF-1<800ng/ml; n = 24) and healthy cats without known endocrinopathy or cardiovascular disease (n = 16). Echocardiography was performed in all cases, including after hypersomatotropism treatment where applicable. Additionally, tissue samples from deceased cats with hypersomatotropism, hypertrophic cardiomyopathy and age-matched controls (n = 21 each) were collected and systematically histopathologically reviewed and compared.</p><p>Results</p><p>By echocardiography, cats with hypersomatotropism had a greater maximum LV wall thickness (6.5mm, 4.1–10.1mm) than diabetic (5.9mm, 4.2–9.1mm; Mann Whitney, p<0.001) or control cats (5.2mm, 4.1–6.5mm; Mann Whitney, p<0.001). Left atrial diameter was also greater in cats with hypersomatotropism (16.6mm, 13.0–29.5mm) than in diabetic (15.4mm, 11.2–20.3mm; Mann Whitney, p<0.001) and control cats (14.0mm, 12.6–17.4mm; Mann Whitney, p<0.001). After hypophysectomy and normalization of IGF-1 concentration (n = 20), echocardiographic changes proved mostly reversible. As in humans, histopathology of the feline acromegalic heart was dominated by myocyte hypertrophy with interstitial fibrosis and minimal myofiber disarray.</p><p>Conclusions</p><p>These results demonstrate cats could be considered a naturally occurring model of acromegalic cardiomyopathy, and as such help elucidate mechanisms driving cardiovascular remodeling in this disease.</p></div

Development of a battery of instruments for detailed measurement of health status in patients with COPD in routine care: the Nijmegen Clinical Screening Instrument

Contains fulltext : 80284.pdf (publisher's version ) (Closed access)PURPOSE: To compose a battery of instruments that provides a detailed assessment of health status (HS) in COPD but that is applicable and clinically meaningful in routine care. METHODS: In a previous study, we developed the Nijmegen Integral Assessment Framework (NIAF) that organizes existing tests and instruments by the sub-domains of HS they measure. Based on clinical and statistical criteria (correlation coefficients and Cronbach alpha's) we selected for each sub-domain instruments from the NIAF. A COPD-study group was used to determine c-scores, and two control groups were used to determine the score ranges indicating normal functioning versus clinically relevant problems for each sub-domain. Existing questionnaire completion software (TestOrganiser) was adapted to enhance clinical applicability. RESULTS: The NCSI measures eleven sub-domains of physiological functioning, symptoms, functional impairment, and quality of life. The TestOrganiser automatically processes the data and produces the graphical PatientProfileChart, which helps to easily interpret results. This envisages the problem areas and discrepancies between the different sub-domains. CONCLUSION: The NCSI provides a valid and detailed picture of a patient's HS within 15-25 min. In combination with the PatientProfileChart, the NCSI can be used perfectly in routine care as screening instrument and as a guide in patient-tailored treatment