bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment of Articular Cartilage Defects of the Knee With Microfracture and Enhanced Microfracture Techniques
Authors: Case Jordan M. , Scopp Jason M.
Published: April 2016

Chondral injuries in the knee are a common source of pain and morbidity. Treatment of symptomatic chondral defects is challenging due to the limited healing capacity of articular cartilage. Microfracture is the most common surgical technique used to treat chondral defects in the knee and utilizes marrow stimulation to generate a fibrocartilage repair. Microfracture has demonstrated good short-term postoperative outcomes. Long-term outcomes following microfracture are variable, with loss of improvement attributed to the poor mechanical qualities of the fibrous repair tissue. Current research is focusing on ways to optimize the repair environment after microfracture using biological scaffolds (enhanced microfracture) to facilitate chondrogenic differentiation and proliferation to improve the quality of repair tissue.
Genetic and epigenetic determinants of B-cell lymphoma evolution
Authors: Izzo Franco , Landau Dan A.
Published: April 2016

Purpose of review

The success of targeted therapies fostered the development of increasingly specific and effective therapeutics for B-cell malignancies. However, cancer plasticity facilitates disease relapse, whereby intratumoral heterogeneity fuels tumor evolution into a more aggressive and resistant form. Understanding cancer heterogeneity and the evolutionary processes underlying disease relapse is key for overcoming this limitation of current treatment strategies. In the present review, we delineate the current understanding of cancer evolution and the advances in both genetic and epigenetic fields, with a focus on non-Hodgkin B-cell lymphomas.

Recent findings

The use of massively parallel sequencing has provided insights into tumor heterogeneity, allowing determination of intratumoral genetic and epigenetic variability and identification of cancer driver mutations and (epi-)mutations. Increased heterogeneity prior to treatment results in faster disease relapse, and in many cases studying pretreatment clonal admixtures predicts the future evolutionary trajectory of relapsed disease.

Understanding the mechanisms underlying tumor heterogeneity and evolution provides valuable tools for the design of therapy within an evolutionary framework. This framework will ultimately aid in accurately predicting the evolutionary paths of B-cell malignancies, thereby guiding therapeutic strategies geared at directly anticipating and addressing cancer evolution.
Distraction Osteogenesis for Surgical Treatment of Craniosynostosis: A Systematic Review
Authors: Mundinger Gerhard S. , Rehim Shady A. , Johnson Owen , Zhou Joy , Tong Anne , Wallner Christopher , Dorafshar Amir H.
Published: April 2016

Background:

Distraction osteogenesis has been proposed as an alternative to cranial remodeling surgery for craniosynostosis, but technique descriptions and outcome analyses are limited to small case series. This review summarizes operative characteristics and outcomes of distraction osteogenesis and presents data comparing distraction osteogenesis to cranial remodeling surgery.

Methods:

A systematic review of the literature was undertaken. Descriptive analysis, operative technical data, outcomes, or postoperative complications of distraction osteogenesis for craniosynostosis were included.

Results:

A total of 1325 citations were reviewed, yielding 53 articles and 880 children who underwent distraction osteogenesis for craniosynostosis. Distraction plates were used in 754 patients (86 percent), whereas springs were used for the remaining 126 patients (14 percent). Standard and spring distraction osteogenesis was reported to successfully treat the primary condition 98 percent of the time. Suboptimal results were reported in 11 patients (1.3 percent), and minor complications were reported in 19.5 percent of cases (n = 172).Major complications were rare, occurring in 3.5 percent of cases (n = 31), and included two reported deaths. Absolute operative times and blood loss were marginally greater for cranial remodeling surgery cases, but the differences were not statistically significant.

Conclusions:

Distraction osteogenesis is an effective cranial vault remodeling technique for treating craniosynostosis. No statistical differences were found with respect to operative time, blood loss, need for transfusion, or intensive care unit resources compared with cranial remodeling surgery. Outcome studies with longer follow-up periods specifically investigating cost, relapse, and reoperation rates are necessary to effectively compare this treatment modality as an alternative to cranial remodeling surgery.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, IV.
Peculiar orientational disorder in 4-bromo-4′-nitrobiphenyl (BNBP) and 4-bromo-4′-cyanobiphenyl (BCNBP) leading to bipolar crystals
Authors: Burgener Matthias , Aboulfadl Hanane , Labat Gaël Charles , Bonin Michel , Sommer Martin , Sankolli Ravish , Wübbenhorst Michael , Hulliger Jürg
Published: April 2016

180° orientational disorder of molecular building blocks can lead to a peculiar spatial distribution of polar properties in molecular crystals. Here we present two examples [4-bromo-4′-nitrobiphenyl (BNBP) and 4-bromo-4′-cyanobiphenyl (BCNBP)] which develop into a bipolar final growth state. This means orientational disorder taking place at the crystal/nutrient interface produces domains of opposite average polarity for as-grown crystals. The spatial inhomogeneous distribution of polarity was investigated by scanning pyroelectric microscopy (SPEM), phase-sensitive second harmonic microscopy (PS-SHM) and selected volume X-ray diffraction (SVXD). As a result, the acceptor groups (NO2or CN) are predominantly present at crystal surfaces. However, the stochastic process of polarity formation can be influenced by adding a symmetrical biphenyl to a growing system. For this case, Monte Carlo simulations predict an inverted net polarity compared with the growth of pure BNBP and BCNBP. SPEM results clearly demonstrate that 4,4′-dibromobiphenyl (DBBP) can invert the polarity for both crystals. Phenomena reported in this paper belong to the most striking processes seen for molecular crystals, demonstrated by a stochastic process giving rise to symmetry breaking. We encounter here further examples supporting the general thesis that monodomain polar molecular crystals for fundamental reasons cannot exist.
Crystal structure of 3-benzamido-1-(4-nitrobenzyl)quinolinium trifluoromethanesulfonate
Authors: Nicolas-Gomez Mariana , Bazany-Rodríguez Iván J. , Plata-Vargas Eduardo , Hernández-Ortega Simón , Dorazco-González Alejandro
Published: April 2016

In the title compound, C23H18N3O3+·CF3SO3−, the asymmetric unit contains two crystallographically independent organic cations with similar conformations. Each cation shows a moderate distortion between the planes of the amide groups and the quinolinium rings with dihedral angles of 14.90 (2) and 31.66 (2)°. The quinolinium and phenyl rings are slightly twisted with respect to each other at dihedral angles of 6.99 (4) and 8.54 (4)°. The trifluoromethanesulfonate anions are linked to the organic cationsviaN—H...O hydrogen-bonding interactions involving the NH amide groups. In the crystal, the organic cations are linked by weak C—H...O(nitro group) interactions into supramolecular chains propagating along theb-axis direction.
Crystal structure of (+)-N-[(1R,5S,6S,9S)-5-hydroxymethyl-3,3,9-trimethyl-8-oxo-2,4,7-trioxabicyclo[4.3.0]nonan-9-yl]acetamide
Authors: Oishi Takeshi , Tsuzaki Shun , Sugai Tomoya , Sato Takaaki , Chida Noritaka
Published: April 2016

In the title compound, C12H19NO6, the six-membered 1,3-dioxane ring adopts a chair-like conformation. The seat of this chair, containing two O atoms, is essentially planar, with a maximum deviation of 0.0021 (12) Å. The five-membered oxolane ringcis-fused to the 1,3-dioxane ring adopts an envelope form. The bridgehead C atom at the flap, which is bonded to the tetrasubstituted C atom of the oxolane ring, deviates from the mean plane of other ring atoms by 0.539 (4) Å. In the crystal, classical O—H...O and N—H...O hydrogen bonds link the molecules into a sheet structure enclosing anR44(24) graph-set motif. Weak intermolecular C—H...O interactions support the sheet formation.
Crystal structure ofcatena-poly[[(dimethyl sulfoxide-κO)(pyridine-2,6-dicarboxylato-κ3O,N,O′)nickel(II)]-μ-pyrazine-κ2N:N′]
Authors: Liu Chen , Thuijs Annaliese E. , Felts Ashley C. , Ballouk Hamza F. , Abboud Khalil A.
Published: April 2016

The title coordination polymer, [Ni(C7H3NO4)(C4H4N2)(C2H6OS)]n, consists of [010] chains composed of NiIIions linked by bis-monodentate-bridging pyrazine molecules. Each of the two crystallographically distinct NiIIions is located on a mirror plane and is additionally coordinated by a dimethyl sulfoxide (DMSO) ligand through the oxygen atom and by a tridentate 2,6-pyridine-dicarboxylic acid dianion through one of each of the carboxylate oxygen atoms and the pyridine nitrogen atom, leading to a distorted octahedral coordination environment. The title structure exhibits an interesting complementarity between coordinative bonding and π–π stacking where the Ni—Ni distance of 7.0296 (4) Å across bridging pyrazine ligands allows the pyridine moieties on two adjacent chains to interdigitate at halfway of the Ni—Ni distance, resulting in π–π stacking between pyridine moieties with a centroid-to-plane distance of 3.5148 (2) Å. The double-chain thus formed also exhibits C—H...π interactions between pyridine C—H groups on one chain and pyrazine molecules on the other chain. As a result, the interior of the double-chain structure is dominated by π–π stacking and C—H... π interactions, while the space between the double-chains is occupied by a C—H...O hydrogen-bonding network involving DMSO ligands and carboxylate groups located on the exterior of the double-chains. This separation of dissimilar interactions in the interior and exterior of the double-chains further stabilizes the crystal structure.
(Z)-2-(5-Fluoro-2-oxoindolin-3-ylidene)-N-methylhydrazinecarbothioamide
Authors: Ali Amna Qasem , Eltayeb Naser Eltaher , Teoh Siang Guan
Published: April 2016

In the title compound, C10H9FN4OS, which is approximately planar with a maximum deviation of 0.0881 (10) Å from the mean plane of the non-H atoms, an intramolecular N—H...O hydrogen bond generates anS(6) ring. In the crystal, molecules are linkedviaN—H...O hydrogen bonds, forming a helical chain along theaaxis. The chains are linked by N—H...S, C—H...S and C—H...F hydrogen bonds and C—H... π interactions into a three-dimensional network.
Social enterprise dualities: implications for social marketing
Authors: Mitchell Alex , Madill Judith , Chreim Samia
Published: April 2016

Purpose

The purpose of this paper is to understand the tensions that marketing practitioners in social enterprises experience, and to explore how these tensions impact the development and implementation of marketing activities.

Design/methodology/approach

Using an approach informed by grounded theory, this paper reports on an investigation of the tensions facing 15 social enterprises. The primary data comprises semi-structured interviews with senior marketing decision-makers, supplemented with archival sources.

Findings

The analysis shows tensions and dualities inform the social and commercial strategic marketing activities of the social enterprises. These tensions and dualities are linked to how the organization obtains financial resources, the nature of the organization’s growth, working with myriad stakeholders and competitive versus cooperative pressures. A model outlining the dualities and their links to marketing activities is developed.

Research limitations/implications

The study provides an in-depth analysis of a small, regional sample of Canadian social enterprises. The study serves as a foundation for future research aimed at elaborating the model we propose.

Practical implications

The findings point to tensions and dualities that play an important role in enabling and restricting the development and implementation of strategic marketing activities in social enterprises. Understanding the nature of these dualities is crucial for social enterprise managers and social marketers as they develop strategic activities.

Social implications

Social enterprises engage in activities that offer substantial social benefits, yet the development of marketing activities in these organizations requires confronting tensions that must be carefully managed.

Originality/value

This paper highlights how dualities facing marketing practitioners in social enterprises influence the development of both social and for-profit marketing activities. The paper offers a model of these dualities. The findings help to extend our understanding of the complex environmental influences impacting marketing practices within social enterprise organizations. Understanding the nature of these environmental influences helps to attune marketers to the potential opportunities and challenges of using social enterprise as an organizational form for launching social marketing programs, as well as providing a theoretical basis for future investigations of marketing practice in social enterprise and social marketing organizations.
Social marketing and value in behaviour?
Authors: Butler Katherine , Gordon Ross , Roggeveen Kate , Waitt Gordon , Cooper Paul
Published: April 2016

Purpose

Drawing on value theory, this study aims to explore the perceived value of using energy efficiently amongst a low-income older population group. It aims to provide an empirical exploration of the concept of value-in-behaviour, and, in doing so, identify that it is a logical addition to the extant concepts of value-in-exchange and value-in-use.

Design/methodology/approach

Exploratory focus group research was conducted to explore older, low-income people’s perceived value towards using energy efficiently in the contexts of their everyday lives. The research was conducted in regional New South Wales, Australia, with 11 focus groups of 59 people (40 females, 19 males) aged over 60 with a personal disposable income below $26,104 per annum.

Findings

Using this framework, functional, economic and ecological value appeared to be the most pertinent value dimensions for using energy efficiently, while social or emotional value was less relevant. Attention is drawn to how value in using energy efficiently emerges within the everyday contingencies and constraints configured by individual households’ financial, social, material and cultural contexts. These findings suggest that programmes in this area and with similar target groups would benefit from trying to promote and co-create such value.

Originality/value

The present study provides empirical evidence that consumers in a social marketing context appear to perceive value-in-behaviour in relation to using energy efficiently. This approach inspires social marketers to foster individual behaviour change through a better understanding of how value is created in everyday practices. This builds upon existing work on value in social marketing and suggests that value is an important concept that warrants continued theoretical, empirical and practical exploration.
Robot‐assisted Fallopian tube transection and anastomosis using the new REVO‐I robotic surgical system: feasibility in a chronic porcine model
Authors: Abdel Raheem Ali , Troya Irela Soto , Kim Dae Keun , Kim Se hoon , Won Park Dong , Joon Park Sung , Hyun Gim Soo , Rha Koon Ho
Published: April 2016

Objectives

To evaluate the feasibility and safety of the new REVO‐I robotic platform by performing Fallopian tube transection and anastomosis in live porcine models.

Subjects and Methods

A prospective chronic animal study was carried out in four crossbred female pigs. The primary outcome was assessment of the pigs’ 2‐week survival. The secondary outcomes were measurements of intra‐operative variables and the complications or difficulties arising when using the REVO‐I.

Results

Fallopian tube anastomosis was successfully performed in four porcine models. The mean (range) operating time was 66 (46–104 min), docking time 22.25 (14–53) min and console time 18 (13–20) min. The REVO‐I robotic system functioned appropriately, with no technical problems or difficulties noted during the procedures. Both the surgeon and the bedside assistants reported ease of use and better performance with subsequent procedures. All pigs were alive 2 weeks after surgery, with no peri‐operative complications related to the use of the robot.

Conclusions

This preclinical chronic porcine study showed that the REVO‐I robotic surgical system is a feasible and safe robotic instrument that can be used by surgeons to perform skillful robotic procedures in porcine models. Our next objective will be to demonstrate its safety in humans.
Reference intervals for biochemical analytes of captive Black‐Fronted Piping‐Guan (Aburria jacutinga)
Authors: Vaz Frederico F. , Locatelli‐Dittrich Rosangela , Lange Rogério R. , Beltrame Olair C. , Przydzimirski Andreise C. , de O. Koch Marília , de Q. Castilhos Bruno
Published: April 2016

Background

Black‐Fronted Piping‐Guan (Aburria jacutinga) is considered one of the most threatened bird species on the American continent. Ex situ conservation efforts have been developed in Brazil, and monitoring the health status of these populations is essential to ensure reproductive success in captivity. Reference intervals (RI) for biochemistry analytes from a larger population of Black‐Fronted Piping‐Guan are unavailable.

Objectives

This study was aimed at establishing RI for biochemical analytes of captive Black‐Fronted Piping‐Guan for future improved health assessments in these animals.

Methods

Blood samples were collected from 32 adult Black‐Fronted Piping‐Guans for serum and plasma separation. Liver and kidney function markers, and concentration of protein and lipids were measured. Reference intervals were determined using an Excel program with Reference Value Adviser (version 2.0).

Results

The RI of the analytes were: AST 20.7–188.0 U/L; CK 713.7–4741.4 U/L; LDH 360.7–1173.7 U/L; γ Glutamyl Transferase 1.1–5.4 U/L; total plasma protein 3.5–6.2 g/dL; total serum protein 1.7–4.7 g/dL; uric acid 0.9–19.2 mg/dL; urea 7.0–25.3 mg/dL; cholesterol 71.8–232.2 mg/dL; triglycerides 25.6–183.4 mg/dL.

Conclusions

The RI are similar to the ones published for other avian species. Only CK and uric acid values were in discordance with the usually reported avian ranges. This could be due to different methods of capture and physical restraint. Alternatively, some differences could be species‐specific. In general, physical restraint should be limited to a minimum and without stress to prevent capture myopathy and death.
Measurement Uncertainty Analysis in Determining Adiabatic Film Cooling Effectiveness by Using Pressure Sensitive Paint Technique
Authors: Johnson Blake , Hu Hui
Published: April 2016

While pressure sensitive paint (PSP) technique has been widely used to measure adiabatic film cooling effectiveness distributions on the surfaces of interest based on a mass transfer analog to traditional thermal-based measurements, very little can be found in literature to provide a comprehensive analysis on the uncertainty levels of the measured film cooling effectiveness distributions derived from PSP measurements. In the present study, a detailed analysis is performed to evaluate the effects of various associated uncertainties in the PSP measurements on the measured film cooling effectiveness distributions over the surfaces of interest. The experimental study is conducted in a low-speed wind tunnel under an isothermal condition. While airflow is used to represent the “hot” mainstream flow, an oxygen-free gas, i.e., carbon dioxide (CO2) gas with a density ratio of DR = 1.5 for the present study, is supplied to simulate the “coolant” stream for the PSP measurements to map the adiabatic film cooling effectiveness distribution over a flat test plate with an array of five cylindrical coolant holes at a span-wise spacing of three diameters center-to-center. A comprehensive analysis was carried out with focus on the measurement uncertainty and process uncertainty for the PSP measurements to determine the film cooling effectiveness distributions over the surface of interest. The final analysis indicates that the total uncertainty in the adiabatic film cooling effectiveness measurements by using the PSP technique depends strongly on the local behavior of the mixing process between the mainstream and coolant flows. The measurement uncertainty is estimated as high as 5% at the near field behind the coolant holes. In the far field away from the coolant holes, the total measurement uncertainty is found to be more uniform throughout the measurement domain and generally lower than those in the near field at about 3%.
Genome Sequence of
Kocuria palustris
Strain CD07_3 Isolated from the Duodenal Mucosa of a Celiac Disease Patient
Authors: Chander Atul Munish , Nair Ramesan Girish , Kaur Gurwinder , Kochhar Rakesh , Mayilraj Shanmugam , Dhawan Devinder Kumar , Bhadada Sanjay Kumar
Published: April 2016

We report here the 2.8-Mb genome of
Kocuria palustris
strain CD07_3 isolated from the duodenal mucosa of a celiac disease (CD) patient. The genome of the bacterium consists of specific virulence factor genes and antibiotic resistance genes that depict its pathogenic potential.
Complete Genome Sequence of
Serratia rubidaea
Isolated in China
Authors: Yao Xue , Sun Qiang , Liu Wenli , Yin Xiuyun , Pei Guangqian , Wang Yunfei , An Xiaoping , Mi Zhiqiang , Luo Yaping , Tong Yigang , Chen Shuiping
Published: April 2016

We report here the first complete genome of
Serratia rubidaea
, isolated from a patient in China.
Anxiolytic-Like Behavioural Effects of Head Electroacupuncture in Rats Susceptible to Stress
Authors: Chen Jia , Barrett Douglas W , He Yuxin , Gonzalez-Lima F
Published: April 2016

Aim

To evaluate the behavioural effects of head electroacupuncture (EA) using the Holtzman rat model, a genetic strain showing susceptibility to stress-evoked helplessness.

Methods

Putative anxiolytic and antidepressant behavioural effects of head EA were investigated using the light-dark and forced swim tests, respectively. The open field test was used to investigate motor activity. A total of 28 rats were used in two experiments, each with two groups (n=7 rats each). Rats were restrained and randomised to handling only (control) or 2Hz EA on the midline head anteriorly (at Yintang) and posteriorly (at GV20) for 3 days (experiment 1) or 4 days (experiment 2).

Results

One day of EA did not modify behaviour in any of the tests (p>0.1); however, 2 days of 2 Hz EA treatment to the head had anxiolytic-like effects, as indicated by an improvement in ambulatory time and average velocity in the light-dark test (experiment 2). Relative to the control group, the EA group demonstrated greater ambulatory time (37.0±3.7 vs 25.2±3.6 s, p<0.05) and lower average velocity (2.73±0.06 vs 3.08±0.13 cm/s, p<0.05). However, EA treatment had no significant effects on the open field and forced swim tests in either experiment.

Conclusions

Two days of EA treatment using 2 Hz pulsating electrical current at midline anterior and posterior acupuncture points on the head induces behavioural effects suggestive of anxiolysis.
Non-small cell lung carcinoma metastasis to the anus
Authors: Dhandapani Ramya Gowri , Anosike Chinedum , Ganguly Akash
Published: April 2016

A 70-year-old man presenting with a lung mass was investigated and treated with pneumonectomy for adenocarcinoma of the lung. He re-presented 3 months later with a large perianal abscess and mass. Subsequent investigations and biopsies showed disseminated metastases from the lung primary. Immunohistochemical staining confirmed the nature of the anal metastasis from the lung adenocarcinoma. Lung cancer is notorious for metastases, hence it is important to be aware of the uncommon modes of spread, which will help obtain early diagnosis and optimise treatment.
Paradoxical embolism via a sinus venosus atrial septal defect causing an inferior ST-segment elevation myocardial infarction in a 23-year-old woman
Authors: O'Sullivan Crochan John , Magarzo Juan Getulio Andras , Bernheim Alain Marcel , Robert Eberli Franz
Published: April 2016

Cerebrovascular accidents constitute the most frequent clinical manifestation of paradoxical embolism. However, it is becoming increasingly recognised that acute myocardial infarction is also an important and potentially life-threatening clinical manifestation of paradoxical embolism. Various intracardiac or pulmonary shunts can provide a convenient conduit for an embolus to traverse from the venous vasculature into the systemic circulation with potentially devastating consequences. We present the case of a 23-year-old woman presenting with chest pain and ST-segment elevation myocardial infarction who ultimately was found to have a sinus venosus atrial septal defect associated with both partial anomalous pulmonary venous drainage and a persistent left superior vena cava.
X-ray laser lines in nickel-like erbium
Authors: Abdelaziz Wessameldin S.
Published: April 2016

Energy levels of 249 excited levels in nickel-like erbium are calculated using the 3s23p63d10 as a ground state and the single electron excited states from n = 3 to n = 4, 5 orbitals, calculations have been performed using FAC code (Gu. Astrophys. J. 582, 1241 (2003). doi:10.1086/344745 ). The populations are calculated over electron densities from 1020 to 1023 cm−3 and electron temperatures 1/2, 3/4 of the ionization potential of Ni-like Er. The gain coefficients of the transitions are calculated.
Fast radio bursts — A brief review: Some questions, fewer answers
Authors: Katz J. I.
Published: April 2016

Fast radio bursts (FRBs) are millisecond bursts of radio radiation at frequencies of about 1 GHz, recently discovered in pulsar surveys. They have not yet been definitively identified with any other astronomical object or phenomenon. The bursts are strongly dispersed, indicating passage through a high column density of low density plasma. The most economical interpretation is that this is the intergalactic medium, indicating that FRB are at “cosmological” distances with redshifts in the range 0.3–1.3. Their inferred brightness temperatures are as high as 10[Formula: see text] K, implying coherent emission by “bunched” charges, as in radio pulsars. I review the astronomical sites, objects and emission processes that have been proposed as the origin of FRB, with particular attention to soft gamma repeaters (SGRs) and giant pulsar pulses.
Proper time regularization at finite quark chemical potential
Authors: Zhang Jin-Li , Shi Yuan-Mei , Xu Shu-Sheng , Zong Hong-Shi
Published: April 2016

In this paper, we use the two-flavor Nambu–Jona-Lasinio (NJL) model to study the quantum chromodynamics (QCD) chiral phase transition. To deal with the ultraviolet (UV) issue, we adopt the popular proper time regularization (PTR), which is commonly used not only for hadron physics but also for the studies with magnetic fields. This regularization scheme can introduce the infrared (IR) cutoff to include quark confinement. We generalize the PTR to zero temperature and finite chemical potential case use a completely new method, and then study the chiral susceptibility, both in the chiral limit case and with finite current quark mass. The chiral phase transition is second-order in [Formula: see text] and [Formula: see text] and crossover at [Formula: see text] and [Formula: see text]. Three sets of parameters are used to make sure that the results do not depend on the parameter choice.
On the gravitational field of a radiating, isothermal perfect gas cloud
Authors: Campos L. M. B. C.
Published: April 2016

The paper considers a static isotropic self-gravitating perfect gas in the presence of thermal radiation. The gravitational field is specified in terms of the radiation and gas pressures. Assuming that the thermodynamic internal energy is small compared with relativistic rest energy, it is shown that the gas pressure satisfies the Lane–Emden equation; the assumption of dominant intrinsic relativistic rest energy is satisfied by the hottest stars. Six-solutions of the Lane–Enden equation are obtained together with the corresponding gravitational fields. The basis for comparison is the singular solution I decaying like the inverse square of the radius, that is the leading term of the asymptotic solution V. Two semi-linear solutions are obtained using as variables nonlinear functions of the gas pressure, leading to nonlinear second-order differential equations that can be linearized; one solution II holds for small radius and leads to zero, finite or infinite central pressure, and the other solution III holds asymptomatically and exhibits pressure oscillations. The singular solution I for large radius is matched to a power series solution IV for small radius leading to a solution valid for all radii. The asymptotic solutions III and V: (i) coincide in their common domain of validity; (ii) can be truncated with good accuracy leading to the solution VI.
Light absorption in distorted graphene
Authors: Hernández-Ortiz Saúl , Valenzuela David , Raya Alfredo , Sánchez-Madrigal Saúl
Published: April 2016

We model the low energy dynamics of graphene in the continuum in terms of a version of reduced quantum electrodynamics (QED) restricting fermions to a [Formula: see text]-dimensional brane, while photons remain within the [Formula: see text]-dimensional bulk. For charge carriers, besides the Dirac mass gap, we consider a Haldane mass term which is induced by parametrizing an effective parity [Formula: see text] and time-reversal [Formula: see text] symmetry breaking that occurs on the brane when distortions of the honeycomb array are such that the equivalence between sublattices is lost. We make use of the relativistic Kubo formula and carry out an explicit calculation of the transverse conductivity. As expected, the filling factor is a half (in natural units) for each fermion species. Furthermore, assuming that a sample of this material is radiated perpendicularly with polarized monochromatic light of frequency [Formula: see text], from the modified Maxwell’s equations we address the problem of light absorption in graphene in terms of the said conductivity. We observe that light penetrating the sample changes its angle of polarization solely by effect of the induced mass, in analogy to the Faraday effect but in absence of magnetic fields. This effect might be relevant for the development of optic filters based on mechanical stretching of graphene flakes.
High-Precision Digital Constant Current Controller with Demagnetization-Time Compensation for Primary-Side Regulation Flyback Converter
Authors: Chang Changyuan , Huang Xiaomin , Li Yuanye , Chen Yao
Published: April 2016

A novel digital constant output current controller with demagnetization-time compensation for flyback converter is proposed in this paper. The secondary winding demagnetization time [Formula: see text] is sampled from the comparison module output signal by output voltage sampling state machine. The ratio between [Formula: see text] and switching period [Formula: see text] is kept constant by bidirectional counter module to achieve constant output current based on invariable primary-side peak-current. Meanwhile, demagnetization-time compensation is proposed in order to enhance load regulation ratio. The compensation [Formula: see text] acquired from a look-up table, is utilized to compensate the impacts caused by the delay [Formula: see text] from the process of sampling the signal of [Formula: see text]. The digital controller (DC) is implemented by hardware description language Verilog HDL. Experimental results of the proposed 2A constant current output flyback converter based on FPGA(EP2C8Q208C8N) indicate that the constant current precision is within [Formula: see text]1% in a wide range of universal-input AC voltage from 110[Formula: see text]V to 240[Formula: see text]V and the voltage load range between 2[Formula: see text]V and 8[Formula: see text]V.
Certain Investigation on Multilevel Inverters for Photovoltaic Grid Connected System
Authors: Karuppusamy P. , Vijayakumar G. , Sathishkumar S.
Published: April 2016

This paper presents a photovoltaic (PV) system to convert the solar energy into electrical energy. DC power from PV system is converted into AC power using multilevel inverters. Cascaded H-bridge (CHB) inverter and diode clamped inverter (DCI) are used to convert variable DC power into sinusoidal AC power. Harmonic content is the important part to improve the efficiency of the inverter. Harmonics of CHB inverter and DCI are simulated and analyzed with different pulse width modulation (PWM) techniques.
Efficient Spectral Collocation Algorithm for Solving Parabolic Inverse Problems
Authors: Bhrawy A. H. , Abdelkawy M. A.
Published: April 2016

This paper reports a new Legendre–Gauss–Lobatto collocation (SL-GL-C) method to solve numerically two partial parabolic inverse problems subject to initial-boundary conditions. The problem is reformulated by eliminating the unknown functions using some special assumptions based on Legendre–Gauss—Lobatto quadrature rule. The SL-GL-C is utilized to solve nonclassical parabolic initial-boundary value problems. Accordingly, the inverse problem is reduced into a system of ordinary differential equations (ODEs) and afterwards, such system can be solved numerically using implicit Runge–Kutta (IRK) method of order four. Four examples are introduced to demonstrate the applicability, validity, effectiveness and stable approximations of the present method. Numerical results show the exponential convergence property and error characteristics of presented method.
The Path to Thioredoxin and Redox Regulation in Chloroplasts
Authors: Buchanan Bob B.
Published: April 2016

After a brief discussion of my graduate work at Duke University, I describe a series of investigations on redox proteins at the University of California, Berkeley. Starting with ferredoxin from fermentative bacteria, the Berkeley research fostered experiments that uncovered a pathway for fixing CO2 in bacterial photosynthesis. The carbon work, in turn, opened new vistas, including the discovery that thioredoxin functions universally in regulating the Calvin-Benson cycle in oxygenic photosynthesis. These experiments, which took place over a 50-year period, led to the formulation of a set of biological principles and set the stage for research demonstrating a role for redox in the regulation of previously unrecognized processes extending far beyond photosynthesis.
Radiation-induced afferent arteriolar endothelial-dependent dysfunction involves decreased epoxygenase metabolites
Authors: Imig John D. , Hye Khan Md. Abdul , Sharma Amit , Fish Brian L. , Mandel Neil S. , Cohen Eric P.
Published: April 2016

Chronic kidney disease is a known complication of hematopoietic stem cell transplant (HSCT) and can be caused by irradiation at the time of the HSCT. In our rat model there is a 6- to 8-wk latent period after irradiation that leads to the development of proteinuria, azotemia, and hypertension. The current study tested the hypothesis that decreased endothelial-derived factors contribute to impaired afferent arteriolar function in rats exposed to total body irradiation (TBI). WAG/RijCmcr rats underwent 11 Gy TBI, and afferent arteriolar responses to acetylcholine were determined at 1, 3, and 6 wk. Blood pressure and blood urea nitrogen were not different between control and irradiated rats. Afferent arteriolar diameters were not altered in irradiated rats. Impaired endothelial-dependent responses to acetylcholine were evident at 3 and 6 wk following TBI. Nitric oxide synthase (NOS), cyclooxygenase (COX), and epoxygenase (EPOX) contribution to acetylcholine dilator responses were evaluated. NOS inhibition with NG-nitro-l-arginine methyl ester (l-NAME) reduced acetylcholine responses by 50% in controls and 90% in 3-wk TBI rats. COX inhibition with indomethacin did not significantly alter the acetylcholine response in the presence or absence of l-NAME. EPOX inhibition with N-methylsulfonyl-6-(2-propargyloxyphenyl)hexanamide significantly decreased acetylcholine responses (35%) in controls but did not significantly alter acetylcholine responses (4%) in TBI rats. Biochemical analysis revealed decreased urinary EPOX metabolites but no change in COX, NOS, or reactive oxygen species at 3 wk TBI. Taken together, these results indicate that afferent arteriolar endothelial dysfunction involves a decrease in EPOX metabolites that precedes the development of proteinuria, azotemia, and hypertension in irradiated rats.
Mesenchymal stem cells preserve neonatal right ventricular function in a porcine model of pressure overload
Authors: Wehman Brody , Sharma Sudhish , Pietris Nicholas , Mishra Rachana , Siddiqui Osama T. , Bigham Grace , Li Tieluo , Aiello Emily , Murthi Sarah , Pittenger Mark , Griffith Bartley , Kaushal Sunjay
Published: April 2016

Limited therapies exist for patients with congenital heart disease (CHD) who develop right ventricular (RV) dysfunction. Bone marrow-derived mesenchymal stem cells (MSCs) have not been evaluated in a preclinical model of pressure overload, which simulates the pathophysiology relevant to many forms of CHD. A neonatal swine model of RV pressure overload was utilized to test the hypothesis that MSCs preserve RV function and attenuate ventricular remodeling. Immunosuppressed Yorkshire swine underwent pulmonary artery banding to induce RV dysfunction. After 30 min, human MSCs (1 million cells, n = 5) or placebo ( n = 5) were injected intramyocardially into the RV free wall. Serial transthoracic echocardiography monitored RV functional indices including 2D myocardial strain analysis. Four weeks postinjection, the MSC-treated myocardium had a smaller increase in RV end-diastolic area, end-systolic area, and tricuspid vena contracta width ( P < 0.01), increased RV fractional area of change, and improved myocardial strain mechanics relative to placebo ( P < 0.01). The MSC-treated myocardium demonstrated enhanced neovessel formation ( P < 0.0001), superior recruitment of endogenous c-kit+ cardiac stem cells to the RV ( P < 0.0001) and increased proliferation of cardiomyocytes ( P = 0.0009) and endothelial cells ( P < 0.0001). Hypertrophic changes in the RV were more pronounced in the placebo group, as evidenced by greater wall thickness by echocardiography ( P = 0.008), increased cardiomyocyte cross-sectional area ( P = 0.001), and increased expression of hypertrophy-related genes, including brain natriuretic peptide, β-myosin heavy chain and myosin light chain. Additionally, MSC-treated myocardium demonstrated increased expression of the antihypertrophy secreted factor, growth differentiation factor 15 (GDF15), and its downstream effector, SMAD 2/3, in cultured neonatal rat cardiomyocytes and in the porcine RV myocardium. This is the first report of the use of MSCs as a therapeutic strategy to preserve RV function and attenuate remodeling in the setting of pressure overload. Mechanistically, transplanted MSCs possibly stimulated GDF15 and its downstream SMAD proteins to antagonize the hypertrophy response of pressure overload. These encouraging results have implications in congenital cardiac pressure overload lesions.
Endothelial-to-mesenchymal transition in lipopolysaccharide-induced acute lung injury drives a progenitor cell-like phenotype
Authors: Suzuki Toshio , Tada Yuji , Nishimura Rintaro , Kawasaki Takeshi , Sekine Ayumi , Urushibara Takashi , Kato Fumiaki , Kinoshita Taku , Ikari Jun , West James , Tatsumi Koichiro
Published: April 2016

Pulmonary vascular endothelial function may be impaired by oxidative stress in endotoxemia-derived acute lung injury. Growing evidence suggests that endothelial-to-mesenchymal transition (EndMT) could play a pivotal role in various respiratory diseases; however, it remains unclear whether EndMT participates in the injury/repair process of septic acute lung injury. Here, we analyzed lipopolysaccharide (LPS)-treated mice whose total number of pulmonary vascular endothelial cells (PVECs) transiently decreased after production of reactive oxygen species (ROS), while the population of EndMT-PVECs significantly increased. NAD(P)H oxidase inhibition suppressed EndMT of PVECs. Most EndMT-PVECs derived from tissue-resident cells, not from bone marrow, as assessed by mice with chimeric bone marrow. Bromodeoxyuridine-incorporation assays revealed higher proliferation of capillary EndMT-PVECs. In addition, EndMT-PVECs strongly expressed c- kit and CD133. LPS loading to human lung microvascular endothelial cells (HMVEC-Ls) induced reversible EndMT, as evidenced by phenotypic recovery observed after removal of LPS. LPS-induced EndMT-HMVEC-Ls had increased vasculogenic ability, aldehyde dehydrogenase activity, and expression of drug resistance genes, which are also fundamental properties of progenitor cells. Taken together, our results demonstrate that LPS induces EndMT of tissue-resident PVECs during the early phase of acute lung injury, partly mediated by ROS, contributing to increased proliferation of PVECs.
Preproglucagon neurons in the hindbrain have IL-6 receptor-α and show Ca2+ influx in response to IL-6
Authors: Anesten Fredrik , Holt Marie K. , Schéle Erik , Pálsdóttir Vilborg , Reimann Frank , Gribble Fiona M. , Safari Cecilia , Skibicka Karolina P. , Trapp Stefan , Jansson John-Olov
Published: April 2016

Neuronal circuits in the hypothalamus and hindbrain are of importance for control of food intake, energy expenditure, and fat mass. We have recently shown that treatment with exendin-4 (Ex-4), an analog of the proglucagon-derived molecule glucagon-like peptide 1 (GLP-1), markedly increases mRNA expression of the cytokine interleukin-6 (IL-6) in the hypothalamus and hindbrain and that this increase partly mediates the suppression of food intake and body weight by Ex-4. Endogenous GLP-1 in the central nervous system (CNS) is produced by preproglucagon (PPG) neurons of the nucleus of the solitary tract (NTS) in the hindbrain. These neurons project to various parts of the brain, including the hypothalamus. Outside the brain, IL-6 stimulates GLP-1 secretion from the gut and pancreas. In this study, we aim to investigate whether IL-6 can affect GLP-1-producing PPG neurons in the nucleus of the solitary tract (NTS) in mouse hindbrain via the ligand binding part of the IL-6 receptor, IL-6 receptor-α (IL-6Rα). Using immunohistochemistry, we found that IL-6Rα was localized on PPG neurons of the NTS. Recordings of these neurons in GCaMP3/GLP-1 reporter mice showed that IL-6 enhances cytosolic Ca2+ concentration in neurons capable of expressing PPG. We also show that the Ca2+ increase originates from the extracellular space. Furthermore, we found that IL-6Rα was localized on cells in the caudal hindbrain expressing immunoreactive NeuN (a neuronal marker) or CNP:ase (an oligodendrocyte marker). In summary, IL-6Rα is present on PPG neurons in the NTS, and IL-6 can stimulate these cells by increasing influx of Ca2+ to the cytosol from the extracellular space.
A comparison of computational methods for detecting bursts in neuronal spike trains and their application to human stem cell-derived neuronal networks
Authors: Cotterill Ellese , Charlesworth Paul , Thomas Christopher W. , Paulsen Ole , Eglen Stephen J.
Published: April 2016

Accurate identification of bursting activity is an essential element in the characterization of neuronal network activity. Despite this, no one technique for identifying bursts in spike trains has been widely adopted. Instead, many methods have been developed for the analysis of bursting activity, often on an ad hoc basis. Here we provide an unbiased assessment of the effectiveness of eight of these methods at detecting bursts in a range of spike trains. We suggest a list of features that an ideal burst detection technique should possess and use synthetic data to assess each method in regard to these properties. We further employ each of the methods to reanalyze microelectrode array (MEA) recordings from mouse retinal ganglion cells and examine their coherence with bursts detected by a human observer. We show that several common burst detection techniques perform poorly at analyzing spike trains with a variety of properties. We identify four promising burst detection techniques, which are then applied to MEA recordings of networks of human induced pluripotent stem cell-derived neurons and used to describe the ontogeny of bursting activity in these networks over several months of development. We conclude that no current method can provide “perfect” burst detection results across a range of spike trains; however, two burst detection techniques, the MaxInterval and logISI methods, outperform compared with others. We provide recommendations for the robust analysis of bursting activity in experimental recordings using current techniques.
Neurophysiological analytics for all! Free open-source software tools for documenting, analyzing, visualizing, and sharing using electronic notebooks
Authors: Rosenberg David M. , Horn Charles C.
Published: April 2016

Neurophysiology requires an extensive workflow of information analysis routines, which often includes incompatible proprietary software, introducing limitations based on financial costs, transfer of data between platforms, and the ability to share. An ecosystem of free open-source software exists to fill these gaps, including thousands of analysis and plotting packages written in Python and R, which can be implemented in a sharable and reproducible format, such as the Jupyter electronic notebook. This tool chain can largely replace current routines by importing data, producing analyses, and generating publication-quality graphics. An electronic notebook like Jupyter allows these analyses, along with documentation of procedures, to display locally or remotely in an internet browser, which can be saved as an HTML, PDF, or other file format for sharing with team members and the scientific community. The present report illustrates these methods using data from electrophysiological recordings of the musk shrew vagus—a model system to investigate gut-brain communication, for example, in cancer chemotherapy-induced emesis. We show methods for spike sorting (including statistical validation), spike train analysis, and analysis of compound action potentials in notebooks. Raw data and code are available from notebooks in data supplements or from an executable online version, which replicates all analyses without installing software—an implementation of reproducible research. This demonstrates the promise of combining disparate analyses into one platform, along with the ease of sharing this work. In an age of diverse, high-throughput computational workflows, this methodology can increase efficiency, transparency, and the collaborative potential of neurophysiological research.