Conjecture: A Possible nnΛ Resonance

This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.We address the question of whether there might exist a resonance in the nnΛ system, using a rank one separable potential formulation of the Hamiltonian. We explore the eigenvalues of the kernel of the Faddeev equation in the complex energy plane using contour rotation to allow us to analytically continue the kernel onto the second energy sheet. We follow the largest eigenvalue as the nΛ potentials are scaled and the nnΛ continuum is turned into a resonance and then into a bound state of the system

Extensive structure‐activity relationship study of albicidin’s C‐terminal dipeptidic p‐aminobenzoic acid moiety

Albicidin is a recently described natural product that strongly inhibits bacterial DNA gyrase. The pronounced activity, particularly against Gram‐negative bacteria, turns it into a promising lead structure for an antibacterial drug. Hence, structure–activity relationship studies are key for the in‐depth understanding of structural features/moieties affecting gyrase inhibition, antibacterial activity and overcoming resistance. The 27 newly synthesized albicidins give profound insights into possibilities for variations of the C‐terminus. Furthermore, in the present study, a novel derivative has been identified as overcoming resistance posed by the Klebsiella‐protease AlbD. Structural modifications include, for example, azahistidine replacing the previous instable cyanoalanine as the central amino acid, as well as a triazole amide bond isostere between building blocks D and E.BMBF, 03VP00030, Validierung einer neuen antibakteriellen Wirkstoffklasse - AlbiPharmTU Berlin, Open-Access-Mittel - 201

The Large Scale Curvature of Networks

Understanding key structural properties of large scale networks are crucial for analyzing and optimizing their performance, and improving their reliability and security. Here we show that these networks possess a previously unnoticed feature, global curvature, which we argue has a major impact on core congestion: the load at the core of a network with N nodes scales as N^2 as compared to N^1.5 for a flat network. We substantiate this claim through analysis of a collection of real data networks across the globe as measured and documented by previous researchers.Comment: 4 pages, 5 figure

Effect of gamma radiation on different stages of Indian meal moth Plodia interpunctella Hübner (Lepidoptera: Pyralidae)

Indian meal moth Plodia interpunctella Hübner is one of the most important stored products pests in the world. In this research, the effect of gamma irradiation was studied on different developmental stages of this pest and the doses required to prevent each of these developmental stages was investigated. From the results, required dose to prevent larval emergence from irradiated 1 to 24 h eggs was 400 Gray (Gy), and 400 Gy was required to prevent pupae from 15 days old larvae. Also, the dose of radiation required to prevent adult emergence from irradiated 5 days old pupa was 650 Gy. According to the results, dose of 650 Gy is adequate to control all immature stages of this pest. In addition, the effect of gamma ray was studied on developmental stage period of each irradiated existence stage till adult eclosion. The results revealed that there was a dose-dependent increase in the developmental periods, and the growth index of the adults was significantly decreased with increasing dose of radiation administered to the eggs, larvae and pupae too. It is concluded that irradiation can be used as a safe method to control stored pests.Key words: Gamma irradiation, prevention dose, developmental period, growth index, Plodia interpunctella

Minimal impact electro-injection of cells undergoing dynamic shape change reveals calpain activation

AbstractThe ability of neutrophils to rapidly change shape underlies their physiological functions of phagocytosis and spreading. A major problem in establishing the mechanism is that conventional microinjection of substances and indicators interferes with this dynamic cell behaviour. Here we show that electroinjection, a “no-touch” point-and-shoot means of introducing material into the cell, is sufficiently gentle to allow neutrophils to be injected whilst undergoing chemokinesis and spreading without disturbing cell shape change behaviour. Using this approach, a fluorogenic calpain-1 selective peptide substrate was introduced into the cytosol of individual neutrophils undergoing shape changes. These data showed that (i) physiologically elevated cytosolic Ca2+ concentrations were sufficient to trigger calpain-1 activation, blockade of Ca2+ influx preventing calpain activation and (ii) calpain-1 activity was elevated in spreading neutrophil. These findings provide the first direct demonstration of a physiological role for Ca2+ elevation in calpain-1 activation and rapid cell spreading. Electroinjection of cells undergoing dynamic shape changes thus opens new avenues of investigation for defining the molecular mechanism underlying dynamic cell shape changes

Impact of Ramadan fasting on intraocular pressure, visual acuity and refractive errors

Introduction: Fasting evidently influences a variety of physiological parameters that can impact the ocular system. Among these modifications are alterations in insulin secretion, sympathetic activity, free fatty acids, lipid profile, melatonin, cortisol, electrolytes and catecholamines. In this study, we investigated the possible alterations in intraocular pressure (10P), visual acuity and refractive errors during Ramadan fasting. Methods: 10P, visual acuity and refractive errors of both eyes of volunteers were measured on the first and last days of Ramadan (once in the morning and evening). Body weight was measured so as to estimate the amount of dehydration. Data from the two examinations was analysed using one-way analysis of variance. A p -value of less than 0.05 was considered statistically significant. Results: 58 healthy, fasting male volunteers with a mean age of 40.7 +/- 7.1 years participated in the study. Statistical analysis demonstrated no difference in 10P, visual acuity or refractive errors on the first and last days of Ramadan, or within a single day (from morning to evening). Conclusion: Our results reveal that Islamic Ramadan fasting does not profoundly affect physiological 10P, refractive error or visual acuity values in healthy volunteers. However, more detailed investigations using animal models should be designed to evaluate whether fasting has a pivotal influence on pathological conditions. Keywords: body weight, intraocular pressure, Ramadan fasting, refractive errors, visual acuit

Inverse association between cigarette and water pipe smoking and hypertension in an elderly population in Iran: Bushehr elderly health programme.

The collected data in Bushehr Elderly Health (BEH) Program which had detailed the data on participants' smoking status and habits, was analysed to investigate the association between smoking of both water pipes and cigarettes and hypertension in an elderly population. Three thousand elderly men and women who participated in the baseline assessment of the BEH Program-a prospective population-based study being conducted in Bushehr, Iran-were selected randomly through a multistage, stratified cluster sampling method. Systolic and diastolic blood pressures were measured twice using a mercury sphygmomanometer, and researchers asked participants about medical history of hypertension as well as history of cigarette and water pipe smoking. Researchers used binary logistic regression models to assess the association of hypertension and smoking, and found an inverse, statistically significant association between current smoking and hypertension (odds ratio (OR)=0.50 (95% confidence interval (CI)=0.41, 0.60)). The association remained statistically significant after controlling for age, education and body mass index (OR=0.54 (95% CI=0.45, 0.66)). Findings were consistent for cigarette and water pipe smoking by sex (all ORs were inverse and statistically significant). Both cigarette and water pipe smoking were associated with reduced hypertension among older people, but the strength of association was different between men and women and also between cigarette and water pipe smoking. The reasons behind the association as well as the differences observed need to be investigated through more comprehensive, longitudinal studies

Intraphagosomal free Ca2+changes during phagocytosis

Phagocytosis (and endocytosis) is an unusual cellular process that results in the formation of a novel subcellular organelle, the phagosome. This phagosome contains not only the internalised target of phagocytosis but also the external medium, creating a new border between extracellular and intracellular environments. The boundary at the plasma membrane is, of course, tightly controlled and exploited in ionic cell signalling events. Although there has been much work on the control of phagocytosis by ions, notably, Ca2+ ions influxing across the plasma membrane, increasing our understanding of the mechanism enormously, very little work has been done exploring the phagosome/cytosol boundary. In this paper, we explored the changes in the intra-phagosomal Ca2+ ion content that occur during phagocytosis and phagosome formation in human neutrophils. Measuring Ca2+ ion concentration in the phagosome is potentially prone to artefacts as the intra-phagosomal environment experiences changes in pH and oxidation. However, by excluding such artefacts, we conclude that there are open Ca2+ channels on the phagosome that allow Ca2+ ions to “drain” into the surrounding cytosol. This conclusion was confirmed by monitoring the translocation of the intracellularly expressed YFP-tagged C2 domain of PKC-γ. This approach marked regions of membrane at which Ca2+ influx occurred, the earliest being the phagocytic cup, and then the whole cell. This paper therefore presents data that have novel implications for understanding phagocytic Ca2+ signalling events, such as peri-phagosomal Ca2+ hotspots, and other phenomena

Search for gravitational wave bursts in LIGO's third science run

We report on a search for gravitational wave bursts in data from the three LIGO interferometric detectors during their third science run. The search targets subsecond bursts in the frequency range 100-1100 Hz for which no waveform model is assumed, and has a sensitivity in terms of the root-sum-square (rss) strain amplitude of hrss ~ 10^{-20} / sqrt(Hz). No gravitational wave signals were detected in the 8 days of analyzed data.Comment: 12 pages, 6 figures. Amaldi-6 conference proceedings to be published in Classical and Quantum Gravit

Quantum state preparation and macroscopic entanglement in gravitational-wave detectors

Long-baseline laser-interferometer gravitational-wave detectors are operating at a factor of 10 (in amplitude) above the standard quantum limit (SQL) within a broad frequency band. Such a low classical noise budget has already allowed the creation of a controlled 2.7 kg macroscopic oscillator with an effective eigenfrequency of 150 Hz and an occupation number of 200. This result, along with the prospect for further improvements, heralds the new possibility of experimentally probing macroscopic quantum mechanics (MQM) - quantum mechanical behavior of objects in the realm of everyday experience - using gravitational-wave detectors. In this paper, we provide the mathematical foundation for the first step of a MQM experiment: the preparation of a macroscopic test mass into a nearly minimum-Heisenberg-limited Gaussian quantum state, which is possible if the interferometer's classical noise beats the SQL in a broad frequency band. Our formalism, based on Wiener filtering, allows a straightforward conversion from the classical noise budget of a laser interferometer, in terms of noise spectra, into the strategy for quantum state preparation, and the quality of the prepared state. Using this formalism, we consider how Gaussian entanglement can be built among two macroscopic test masses, and the performance of the planned Advanced LIGO interferometers in quantum-state preparation