297 research outputs found
Hysteretic wavelength selection in isometric, unsupported radial wrinkling
In [Pal et al., arXiv:2206.03552], the authors discuss how an unsupported
flat annulus contracted at its inner boundary by a factor , buckles
into a radial wrinkling pattern that is fully isometric and tension-free. What
selects the wavelength in such a pure-bending configuration, in the absence of
any competing sources of work? In this paper, with the support of numerical
simulations, we argue that competition between stretching and bending energies
at local, mesoscopic scales leads to the selection of a wavelength scale
sensitive to both the width and thickness of the sheet:
. This scale
corresponds to an arrest criterion for wrinkle coarsening starting from any
wavelength , which can be interpreted in terms of
both size and energetic barriers to further coarsening. However, the sheet can
support coarser wavelengths: , since there is no
penalty to their existence. Since this wavelength selection mechanism depends
on the value of itself, it is hysteretic.Comment: 8 pages, 4 figures. To be published in Soft Matte
Dynamics of warped compactifications and the shape of the warped landscape
The dynamics of warped/flux compactifications is studied, including warping
effects, providing a firmer footing for investigation of the "landscape." We
present a general formula for the four-dimensional potential of warped
compactifications in terms of ten-dimensional quantities. This allows a
systematic investigation of moduli-fixing effects and potentials for mobile
branes. We provide a necessary criterion, "slope-dominance," for evading
"no-go" results for de Sitter vacua. We outline the ten-dimensional derivation
of the non-perturbative effects that should accomplish this in KKLT examples,
and outline a systematic discussion of their corrections. We show that
potentials for mobile branes receive generic contributions inhibiting slow-roll
inflation. We give a linearized analysis of general scalar perturbations of
warped IIB compactifications, revealing new features for both time independent
and dependent moduli, and new aspects of the kinetic part of the
four-dimensional effective action. The universal Kahler modulus is found_not_
to be a simple scaling of the internal metric, and a prescription is given for
defining holomorphic Kahler moduli, including warping effects. In the presence
of mobile branes, this prescription elucidates couplings between bulk and brane
fields. Our results are thus relevant to investigations of the existence of de
Sitter vacua in string theory, and of their phenomenology, cosmology, and
statistics.Comment: (80 pages; two appendices; harvmac. v3: minor corrections, and
references added. v4: argument that pure Kahler deformations are flat.
A study of effect of medications on patients with non complicated acute bronchitis
Background: Authors define acute bronchitis as a self-limiting infection of large airways, which is characterized by cough without pneumonia. NSAIDS (Non-steroidal anti-inflammatory drugs) are prescribed in patients with Lower Respiratory Tract Infections (LRTI). In cough, fever and chest pain it is common practice to prescribe NSAIDS or antibiotics. Authors have conducted assessment of effect of medications in the resolution of cough of patients with uncomplicated acute bronchitis.Methods: It was a single blinded randomized clinical trial conducted in patients admitted to pulmonary medicine department of government medical college Shivpuri. Patients were from age group 18 to 70 years presenting with respiratory tract infection of less than one week’s duration, with cough as the predominant symptom and diagnosed with non-complicated acute bronchitis. Patients were randomized into two groups, group A and B according to medications.Results: Among 120 participants were randomized (60 to ibuprofen and 60 to antibiotic). The median number of days with frequent cough was slightly lower among patients of group A (12 days) compared with those receiving amoxicillin-clavulanic acid (14 days). No significant difference was found. Adverse effect was seen in 24 patients, which was most common in group B (15.25%) than group A (9.15%). p<0.05).Conclusions: No significant differences were observed in the number of days with cough between patients with uncomplicated acute bronchitis treated with ibuprofen or amoxicillin-clavulanic acid
Cancer awareness among females of urban slums in their reproductive age group
Background: Cancer is major public health problem affecting millions of people worldwide. The prevalence of cancer is increasing in developing world due to increase in life expectancy, increased urbanization and adoption of western life styles. Thus, the present study was carried out to assess the extent of awareness towards cancer among women of urban slums in their reproductive age group. Methods:Community based cross sectional study was carried outby interviewing women of reproductive age group residing in urban slums using pre-designed and pre-tested proforma to assess awareness towards cancer. Descriptive statistics was applied to assess the awareness level and the association between two attributes was calculated bychi-square test. Results: A total of 182 women were interviewed. Out of which 39.56% were in 20-24 years age group. 46.15% were housewives and most of them belonged to middle class families. Though the knowledge regarding cancer, especially about modes of transmission, symptoms and laboratory diagnosis was found satisfactory but was accompanied by misconceptions. 71.43% women were aware about its prevention, mostly by changing life styles and by getting screening done at regular intervals. Conclusion: Thus, impetus has to be laid upon screening regarding cancer during reproductive age group and enlightenment of the women about cancer screening centres available at the hospitals, so as to heighten the knowledge of facilities for a better reproductive life
Faceted wrinkling by contracting a curved boundary
Single-mode deformations of two-dimensional materials, such as the Miura-ori
fold, are important to the design of deployable structures because of their
robustness, but usually require careful pre-patterning of the material. Here,
we show that inward contraction of a curved boundary produces a novel
single-mode deformation without any pre-patterning. Using finite-element
simulations of the contraction of a thin circular annular sheet, we show that
these sheets wrinkle into a structure with negligible stretching energy, in
which the contracted boundary forms spontaneous facets. We construct a strictly
isometric wrinkled surface formed of triangles and cones that matches geometric
and energy features closely, suggesting that this class of partly-faceted
wrinkled deformations is isometric. Isometry favours the restriction of such
deformations to a robust low-bending energy channel that avoids stretching.
This class of buckling also offers a novel way to manipulate sheet morphology
via boundary forces. Finally, it serves as a minimal model for illustrating the
strong constraints imposed by geometry in elastic pattern formation.Comment: V3. Double column. 6 pages, 5 figures + S
Study protocol for the Anesthesiology Control Tower—Feedback Alerts to Supplement Treatments (ACTFAST-3) trial: A pilot randomized controlled trial in intraoperative telemedicine [version 1; referees: 2 approved]
Background: Each year, over 300 million people undergo surgical procedures worldwide. Despite efforts to improve outcomes, postoperative morbidity and mortality are common. Many patients experience complications as a result of either medical error or failure to adhere to established clinical practice guidelines. This protocol describes a clinical trial comparing a telemedicine-based decision support system, the Anesthesiology Control Tower (ACT), with enhanced standard intraoperative care. Methods: This study is a pragmatic, comparative effectiveness trial that will randomize approximately 12,000 adult surgical patients on an operating room (OR) level to a control or to an intervention group. All OR clinicians will have access to decision support software within the OR as a part of enhanced standard intraoperative care. The ACT will monitor patients in both groups and will provide additional support to the clinicians assigned to intervention ORs. Primary outcomes include blood glucose management and temperature management. Secondary outcomes will include surrogate, clinical, and economic outcomes, such as incidence of intraoperative hypotension, postoperative respiratory compromise, acute kidney injury, delirium, and volatile anesthetic utilization. Ethics and dissemination: The ACTFAST-3 study has been approved by the Human Resource Protection Office (HRPO) at Washington University in St. Louis and is registered at clinicaltrials.gov (NCT02830126). Recruitment for this protocol began in April 2017 and will end in December 2018. Dissemination of the findings of this study will occur via presentations at academic conferences, journal publications, and educational materials
Microvascular function in pre-eclampsia is influenced by insulin resistance and an imbalance of angiogenic mediators
In preeclampsia, maternal microvascular function is disrupted and angiogenesis is dysfunctional. Insulin resistance that occurs in some pregnancies also pathologically affects microvascular function. We wished to examine the relationship of angiogenic mediators and insulin resistance on microvascular health in pregnancy. We performed a nested, case-control study of 16 women who developed preeclampsia with 17 normal pregnant controls. We hypothesized that the impaired microvascular blood flow in preeclamptic women associated with an increased ratio of the antiangiogenic factors; (s-endoglin [sEng] and soluble fms-like tyrosine kinase-1 [sFlt-1]) and proangiogenic molecule (placental growth factor [PlGF]) could be influenced by insulin resistance. Serum samples taken after 28 weeks of gestation were measured for the angiogenic factors, insulin, and glucose alongside the inflammatory marker; tumor necrosis factor-α and endothelial activation, namely; soluble vascular cell adhesion molecule 1, intercellular adhesion molecule-1, and e-selectin. Maternal microvascular blood flow, measured by strain gauge plethysmography, correlated with ratios of pro- and antiangiogenic mediators independently of preeclampsia. Decreased microvascular function measured in preeclampsia strongly correlated with both the antiangiogenic factor (sFlt-1 + sEng): PlGF ratio and high levels of insulin resistance, and combining insulin resistance with antiangiogenic factor ratios further strengthened this relationship. In pregnancy, microvascular blood flow is strongly associated with perturbations in pro- and antiangiogenic mediators. In preeclampsia, the relationship of maternal microvascular dysfunction with antiangiogenic mediators is strengthened when combined with insulin resistance
Characteristic noise features in light transmission across membrane protein undergoing photocycle
We demonstrate a technique based on noise measurements which can be utilized
to study dynamical processes in protein assembly. Direct visualization of
dynamics in membrane protein system such as bacteriorhodopsin (bR) upon
photostimulation are quite challenging. bR represents a model system where the
stimulus-triggered structural dynamics and biological functions are directly
correlated. Our method utilizes a pump-probe near field microscopy method in
the transmission mode and involves analyzing the transmittance fluctuations
from a finite size of molecular assembly. Probability density distributions
indicating the effects of finite size and statistical correlations appear as a
characteristic frequency distribution in the noise spectra of bR whose origin
can be traced to photocycle kinetics. Valuable insight into the molecular
processes were obtained from the noise studies of bR and its mutant D96N as a
function of external parameters such as temperature, humidity or presence of an
additional pump source.Comment: 13 Pages, 3 Figures, To appear in the Journal of Chemical Physics,
Vol. 134, Issue
- …