bluuebunny/crossref_metadata_2025 huggingface dataset:
Pseudarthrosen und schlecht heilende Frakturen am Humerusschaft und am distalen Humerus
Authors: Plecko Michael
Published: November 2019

Frakturen am Humerusschaft werden häufig konservativ im Brace behandelt und werden allgemein als benigne Frakturen mit hoher Heilungspotenz eingestuft. Dennoch kommt es, je nach Abschnitt, in 12 – 24% zur Ausbildung einer Pseudarthrose. Meist ist die Funktionalität des Armes so gestört, dass eine operative Behandlung notwendig wird. Eine exakte Analyse ist für den Erfolg der Therapie unumgänglich. Die Plattenosteosynthese, bevorzugt mit interfragmentärer Kompression und Anlagerung autologer Knochenspäne, führt in der überwiegenden Mehrzahl der Fälle zu einer raschen und soliden Heilung und ermöglich gleichzeitig die Korrektur relevanter Fehlstellungen. Bei atrophen Pseudarthrosen sind zusätzlich Maßnahmen zur Verbesserung der lokalen Biologie notwendig. Am distalen Humerus ist häufiger die suprakondyläre Region betroffen. Hier steht die Einstauchung und Kompression der Knochenenden gegeneinander sowie die Defektauffüllung mit autologen Knochenspänen im Vordergrund. Eine Doppelplattenosteosynthese sorgt für ausreichende Stabilität. Ein ausgedehntes Kapselrelease verhindert eine erhöhte Belastung der Frakturzone und verhindert eine zu starke postoperative Bewegungseinschränkung. Bei Fällen, die nicht stabil rekonstruierbar sind, stellt die Ellbogentotalendoprothese eine sehr gute Rettungsoperation dar.
Hämodialyse
Authors: Wiederhold Dietmar
Published: November 2019

In den letzten Jahren hat die Anzahl älterer Dialysepatienten in den meisten Ländern zugenommen. Diese vulnerable Gruppe benötigt aufgrund von zahlreichen Komorbiditäten, mangelnder sozialer Unterstützung und verschiedenen Formen von Stress mehr Aufmerksamkeit und Unterstützungsleistungen. Dennoch ist über die besondere Sichtweise älterer Dialysepatienten und deren Vorstellungen zur Krankheit, Behandlung und Akzeptanz bisher wenig bekannt. Das Ziel der Studie war es, die Erfahrungen älterer Patienten an der Hämodialyse (HD) zu untersuchen.
Salz- und Wasser-Zufuhr bei Dialysepatienten
Authors: Mohaupt Markus
Published: November 2019

Die Regulation von Na+ und Aldosteron ist komplex und eng mit dem Renin-Angiotensin-II-Aldosteron-System (RAAS) verknüpft. Die Aldosteron-Renin-Relation wird in physiologischen und pathophysiologischen Situationen, z. B. durch eine Hämodialysebehandlung, entkoppelt. Zudem ist die Angiotensin-I-Aktivierung durch das Angiontensin I Converting Enzyme (ACE) gesteigert. Komplizierend ist Na+ mit unterschiedlichen Wirkungen kompartimentalisiert: extrazellulär volumenwirksam, ossär zum langsamen Austausch gespeichert und wasserfrei im Gewebe tonizitätsassoziiert metabolisch aktiv. Eine spezifisch Na+-arme Diät ist nicht sinnvoll, da sie mit einer höheren Mortalität assoziiert ist. Jedoch scheint bei sonst gutem Ernährungszustand eine Kochsalz-Zufuhr von unter 6–7 g/d und eine geringe interdialytische Gewichtszunahme vorteilhaft für das Überleben zu sein. Studien zum Dialysat-Na+ sind von mäßiger Qualität und zeigen, dass ein tieferes Dialysat-Na+ zu einer geringeren interdialytischen Gewichtszunahme, zu einem niedrigeren prädialytischen Blutdruck und zu einem reduzierten Einsatz von Antihypertensiva führt. Krämpfe und intradialytische Blutdruckabfälle nehmen zu. Einige potenzielle Forschungsfragestellungen werden beschrieben.
Long-Term Knowledge Retention after Peer-Assisted Abdominal Ultrasound Teaching: Is PAL a Successful Model for Achieving Knowledge Retention?
Authors: Nourkami-Tutdibi Nasenien , Tutdibi Erol , Schmidt Susanne , Zemlin Michael , Abdul-Khaliq Hashim , Hofer Matthias
Published: November 2019

Background Diagnostic ultrasound has a crucial importance in clinical settings, especially in intensive care medicine where bedside ultrasound has become indispensable. Medical students as well as residents therefore have a strong interest in learning this useful skill. Since staff resources are limited, more and more universities are using student tutors in a peer-assisted learning concept (PAL) to teach medical students early in their training. To date, there is very sparse data about knowledge retention after peer-assisted teaching. The aim of this study was to evaluate whether PAL is a suitable method for teaching complex skills like abdominal ultrasound and to evaluate whether students do achieve adequate long-term knowledge retention after peer-assisted teaching.

Method A total of 40 volunteer 3rd to 5th year students were randomly assigned to a basic abdominal ultrasound course in small training groups of 5 persons each. Participants were evaluated using a pre-post-test design by a validated objective structured clinical examination (OSCE) before and immediately after the course. To measure the retention of knowledge, 15 former participants were randomly selected to repeat the OSCE assessment after one year.

Results All groups showed a significant improvement in practical skills and knowledge gain after the training with mean values of 13.1 for pre-test compared to 83.5 (maximum 100 points) for post-test (p < 0.001). The overall score achieved after one year was 78.7 and did not significantly differ from the post-test result.

Conclusion PAL is effective for teaching abdominal ultrasound. Students were able to accomplish a satisfactory level of ultrasound skills. We further demonstrated that PAL can assure long-term knowledge retention.
An Efficient Synthesis of the Pentasaccharide Repeating Unit of Pseudomonas aeruginosa Psl Exopolysaccharide
Authors: Demeter Fruzsina , Chang Margaret Dah-Tsyr , Lee Yuan-Chuan , Borbás Anikó , Herczeg Mihály
Published: November 2019

Pseudomonas aeruginosa is a biofilm-forming Gram-negative bacterium and a leading cause of life-threatening nosocomial infections. The polysaccharide synthesis locus (Psl) exopolysaccharide of P. aeruginosa is a key constituent of the defending bacterial biofilm layer and is a promising therapeutic target for resistant species. The Psl exopolysaccharide is built up from repeating pentasaccharide units which contain one α- and two β-mannosidic linkages, and one l-rhamnose and one d-glucose moieties. The preparation of this pentasaccharide was first described by Boons et al. in a 34-step synthesis. Based on their work, we have developed a new and effective pathway for the synthesis of the repeating pentasaccharide unit of the Psl exopolysaccharide. We have succeeded in simplifying the synthesis of the l-rhamnose and the α-selective d-mannose building blocks. Furthermore, taking advantage of a chemoselective pre-activation-based β-mannosylation, we directly prepare a thioglycoside disaccharide donor and use it in the next coupling reaction without further transformation. The pentasaccharide, in the form of a p-methoxyphenyl glycoside, is prepared in 26 steps, which is suitable for biological testing.
Air-Induced Disulfenylation of Alkenes: Facile Synthesis of Vicinal Dithioethers
Authors: Yu Guodian , Ou Yingcong , Chen Danyao , Huang Yuanting , Yan Yan , Chen Qian
Published: November 2019

A novel disulfenylation of alkenes with thiophenols and their corresponding disulfides by using air as the oxidant has been achieved. This transformation provides a facile and practical protocol for the synthesis of vicinal dithioethers under mild conditions.
Pyelonephritis in Pregnancy: Relationship of Fever and Maternal Morbidity
Authors: DeYoung Tracey H. , Whittington Julie R. , Ennen Christopher S. , Poole Aaron T.
Published: November 2019

Objective To evaluate the relationship between maternal fever at the time of hospital admission and subsequent maternal morbidity in pregnant patients with pyelonephritis.

Study Design In this retrospective cohort study, inpatient records were reviewed for all obstetric patients discharged from a single tertiary care hospital between June 1, 2011, and May 30, 2017, with the diagnosis of pyelonephritis. Patients were stratified into two groups, those with and without fever at the time of admission. Descriptive statistics were utilized to evaluate the association of fever at the time of presentation with subsequent morbidity. Using admission vital signs, maternal early warning criteria (MEWC) were applied and odds ratios calculated to predict intensive care unit (ICU) admission.

Results A total of 110 patients were admitted with pyelonephritis in pregnancy; 24 patients were febrile and 86 patients were afebrile on admission. There was no difference in rates of maternal ICU admission between both groups. Positive MEWC was predictive of ICU admission with an adjusted odds ratio of 16.54 (95% confidence interval: 1.29–212.5; p = 0.03).

Conclusion Afebrile pregnant patients with pyelonephritis remain at risk of significant maternal morbidity. Application of the MEWC on admission identifies patients at higher risk of ICU admission.
Utility of Upright Weight-bearing Imaging in Total Hip Arthroplasty
Authors: DelSole Edward M. , Mercuri John J.
Published: November 2019

Planning for total hip arthroplasty (THA) has traditionally been performed using static supine anteroposterior radiographs of the pelvis. Recent advances in imaging technology and the understanding of human spinopelvic kinematics have made weight-bearing radiography an important adjunct to supine imaging. Hip surgeons can use weight-bearing imaging to optimize THA component position to prevent hip instability and early component wear. The goal of this narrative review is to delineate the fundamentals of spinopelvic kinematics, the benefits of surgical planning using weight-bearing radiography, and the underpinnings of upright full-body stereoradiography as a useful adjunct to traditional supine radiographs.
Intraoperative Ultrasound Leads to Conservative Management of Benign Ovarian Tumors: A Retrospective, Single-Center Study
Authors: Badiglian-Filho Levon , Menezes Ademir Narciso de Oliveira , Faloppa Carlos Chaves , Fukazawa Elza Mieko , Mantoan Henrique , Kumagai Lillian Yuri , Baiocchi Glauco
Published: November 2019

Objective To evaluate whether the use of intraoperative ultrasound leads to more conservative surgeries for benign ovarian tumors.

Methods Women who underwent surgery between 2007 and 2017 for benign ovarian tumors were retrospectively analyzed. The women were classified into two groups: those who underwent intraoperative ultrasound (group A) and those who did not (group B). In group A, minimally-invasive surgery was performed for most patients (a specific laparoscopic ultrasound probe was used), and four patients were submitted to laparotomy (a linear ultrasound probe was used). The primary endpoint was ovarian sparing surgery (oophoroplasty).

Results Among the 82 cases identified, only 36 met the inclusion criteria for the present study. Out of these cases, 25 underwent intraoperative ultrasound, and 11 did not. There were no significant differences in arterial hypertension, diabetes, smoking history, and body mass index for the two groups (p = 0.450). Tumor diameter was also similar for both groups, ranging from 1 cm to 11 cm in group A and from 1.3 cm to 10 cm in group B (p = 0.594). Tumor histology confirmed mature teratomas for all of the cases in group B and for 68.0% of the cases in group A. When the intraoperative ultrasound was performed, a more conservative surgery was performed (p < 0.001).

Conclusion The use of intraoperative ultrasound resulted in more conservative surgeries for the resection of benign ovarian tumors at our center.
Chronic Distal Radioulnar Joint Dislocation: A Case Report
Authors: Fernandes Leonor , Sousa João , Cruz Fernando
Published: November 2019

Dislocation of the distal radioulnar joint (DRUJ) usually occurs associated with a distal radius fracture. An isolated dislocation, without a radius fracture, is a rare situation.

We present a case of neglected isolated DRUJ dislocation in a 30-year-old manual laborer. The treatment was performed 4 months after the initial injury. Open reduction and fixation were performed. This resulted in a stable, pain-free joint, and the patient resumed his previous work.

Surgical techniques of foveal reattachment and dorsal capsuloplasty have been described for chronic DRUJ instability. An isolated and dislocated DRUJ is an uncommon injury that may be misdiagnosed and initially mistreated. There haven't been many reports in the literature of a case such as this.
Mapeo Doppler color de las perforantes de la arteria colateral radial y su posible aplicación en la realización de colgajos de perforantes para cobertura de defectos en miembro superior
Authors: Torres-Fuentes Carlos Eduardo , Bernal Alexandra , Menze Erica , Castañeda Diego , Ardila Camilo
Published: November 2019

Introducción El uso de los colgajos regionales basados en arterias perforantes musculocutáneas o fasciocutáneas, constituyen una herramienta útil en el manejo en defectos de cobertura complejos.

Objetivo Determinar las características anatómicas de las perforantes de la arteria colateral radial, rama de la arteria braquial profunda, en voluntarios sanos según los hallazgos en la ecografía Doppler color.

Métodos Se realizó un estudio descriptivo, en donde se describió el patrón de las perforantes de la arteria colateral radial (ACR) mediante ecografía Doppler color reportando diámetro, velocidad picosistólica (VPS) y presencia de vena acompañante, en una muestra de 30 voluntarios sanos que cumplieran con los criterios de inclusión.

Resultados Se realizó el estudio doppler color en ambos miembros superiores en 30 voluntarios sanos. Se encontró un promedio de 3,3 vasos perforantes derechos y 3,1 vasos perforantes izquierdos para cada brazo respectivamente, siendo la mayoría musculocutáneas en su curso, de las cuales la mayoría eran distales 67% del lado derecho y 62,7% del lado izquierdo, con un diámetro promedio de 1,3 mm en ambos brazos, velocidad de flujo promedio de 22,9 cm/s del lado derecho y 19,7 cm/s del lado izquierdo, y una distancia promedio al epicóndilo lateral de 8 cm del lado derecho y 7,9 cm del lado izquierdo.

Conclusión Se estableció la presencia, ubicación, tipo y características anatómicas de los vasos perforantes dependiente de la arteria colateral radial con un estudio doppler color, donde se identificó su predominio en el área distal del brazo y se describió la VPS de las perforantes encontradas.
Evaluating the Impact of a New Smartphone Texting Tool on Patient Care in Obstetrics, an Emergent Healthcare Setting
Authors: Feinberg Jacqueline , Shaw Sara , Kashyap Nitu , Illuzzi Jessica , Campbell Katherine , Hsiao Allen L. , Pettker Christian M.
Published: November 2019

Background Hospitals across the country are investing millions of dollars to adopt new Health Insurance Portability and Accountability Act (HIPAA)-compliant secure text messaging systems. However, in nearly all cases, these implementations are occurring without evaluation of their impact on patient care.

Objective To evaluate perceived impact on patient care and workflow of new text messaging system implemented in obstetrics at Yale-New Haven Hospital and to inform guidelines for future implementations in emergent settings.

Methods A new HIPAA-compliant texting system was implemented in obstetrics in 2016. Before implementation of the new system, residents and nurses were surveyed on perceived effect of communication system (pagers with text receiving, service mobile phones, personal cell phones) on clinical workflow and patient care using 5-point Likert scale and open-ended questions. Following roll-out (1 and 6 months), both teams were surveyed with same questions. Results were compared using Wilcoxon–Mann–Whitney test (0–1 months and then 0–6 months). Open-ended question results were qualitatively compared for recurrent unifying themes.

Results In both nursing and resident domains, 1 month after implementation, the new communication system was perceived to significantly improve efficiency and patient care across all metrics. After 6 months, this effect decayed in nearly all categories (including efficiency, real-time communication, and knowledge of covering provider). The exception was nurse's knowledge of which resident to contact and resident's timely evaluation of patient, for which we observed sustained improvements. System shortcomings identified included interrupted connection (i.e., dropped calls), dysfunctional and inaccurate alert system, and unclear identification of the covering provider.

Conclusion A new text-messaging–based communication system may improve efficiency and patient care in emergent settings, but system shortcomings can substantially erode potential benefits over time. We recommend implementers evaluate new systems for a set of specific functional requirements to increase probability of sustained improvement and decrease risk of poor patient outcomes.
Participation patterns of the rainfall index insurance for pasture, rangeland and forage programme
Authors: Goodrich Brittney , Yu Jisang , Vandeveer Monte
Published: November 2019

Using a novel policyholder-level data set, we analyse participants’ choices of 2-month index intervals in the Rainfall Index for Pasture, Rangeland and Forage (RI-PRF) insurance programme. We first provide a conceptual model that illustrates participation patterns of the rainfall index insurance. We then connect these predicted patterns to some empirical evidence from the policyholder-level data set, which is a subset of data provided by the USDA Risk Management Agency for all RI-PRF participants in Nebraska and Kansas during the years 2013–2017. Because the correlations between forage yield and precipitation and the expected premium subsidy vary by month, different degrees of risk aversion may predict distinctively different choices of the 2-month intervals. Using cluster analysis, we group the participants with similar allocation patterns across the 2-month intervals. We observe that the number of participants displaying relatively low levels of risk aversion increase over time. We connect this to the fact that premium subsidies and producer returns associated with non-growing season (risk-increasing) months are often greater than those for growing season (risk-reducing) months, and this has important implications for policy design. Our findings suggest that more research in this area could assist policymakers in keeping the RI-PRF programme in line with its objective of reducing risk for livestock producers.
Direct evaluation method to measure permittivity and conductivity of thin layers via wave approach in the THz region
Authors: Kwak Yunsang , Park Sang Mok , Lee Sinyeob , Kim Hak-Sung , Lee Ju , Park Junhong
Published: November 2019

The direct evaluation method for measuring the permittivity and conductivity of thin layers was proposed via the wave approach in the terahertz (THz) region. The terahertz time-domain spectroscopy (THz-TDS) was employed for performing experiments with thin dielectric layers. The proposed method takes advantage of the wave prediction for propagated THz waves in the thin layer. The transient and spectral responses of the THz waves propagated in the thin layer were predicted directly through the proposed wave approach. The numerical procedures utilizing the predicted waves were presented to derive the complex wavenumber in the THz region, which is composed of the permittivity and conductivity. The derived properties were verified by comparing with the measured behaviors in time and frequency domains. The proposed numerical procedures allow us to measure precisely the complex dielectric property of the thin layer without any pre-estimation for layer inner conditions.
Band structure tailoring in ZrSe2 single crystal via trace rhenium intercalation
Authors: ur Rehman Zia , Wang Sheng , Lawan Mukhtar Adam , Zareen Shah , Moses Oyawale Adetunji , Zhu Wen , Wu Xiaojun , Sun Zhe , Song Li
Published: November 2019

Atomic intercalation can be utilized to engineer the electronic structure of two dimensional layered materials at the atomic scale, thereby governing distinctive properties in comparison with the pristine ones. Herein, a minute amount of Rhenium (Re) atoms (∼1.3% wt.) were controllably intercalated inside the layers of semiconducting Zirconium diselenide (ZrSe2) single crystal. Our angle-resolved photoemission spectroscopy revealed that Re intercalation could move down the bottom of the ZrSe2 conduction band without band dispersion changes, resulting in a small electronic pocket at the Brillouin zone boundary at the M point. The subsequent low-temperature transport results further confirmed the anomalous metallic characteristics in the semiconducting ZrSe2 after low-level Re intercalation.
Carbon nanotube-based lossy transmission line filter for superconducting qubit measurements
Authors: Moghaddam Mehran Vahdani , Chang C. W. Sandbo , Nsanzineza Ibrahim , Vadiraj A. M. , Wilson C. M.
Published: November 2019

In superconducting qubit measurements, stray infrared photons lead to damping processes that degrade quantum coherence. In this Letter, we show that a thermal blocking filter made of multiwalled carbon nanotubes diluted in stainless steel powder can significantly improve the energy relaxation time, T1, and the pure dephasing time, Tφ, of a qubit. By using two independent measurement lines, with and without the filter, and switching between them in situ, we observe that with the filter there is an increase of more than 61% in T1 and 291% in Tφ. We characterize the filter, demonstrating that the scattering parameters remain stable down to 8 mK over a wide range of frequencies, spanning from 10 MHz to 50 GHz. We also show that the cutoff frequency of the filter is easily controlled by selecting the concentration of nanotubes.
Infrared spectroscopy of a small ion solvated by helium: OH stretching region of HeN−HOCO+
Authors: Davies Julia A. , Besley Nicholas A. , Yang Shengfu , Ellis Andrew M.
Published: November 2019

Messenger spectroscopy is a well-established method for recording infrared (IR) spectra of molecular ions. It relies upon the tagging of weakly bound atoms or molecules, known as the “messenger,” to the ion of interest. The ideal tag species is helium since it has the weakest possible interaction with any molecular ion and is consequently the least likely to alter the structure and function. However, the attachment of a helium tag is challenging because of the exceptionally cold conditions that are inherently required. In this work, electron ionization of doped liquid helium nanodroplets has been used to create cations tagged with a variable number (N) of helium atoms. Mass-selective ion detection has made it possible to record IR spectra as a function of N, thus revealing the effect on the structure and charge distribution within the ionic core as solvation becomes more extensive. We illustrate this capability for protonated carbon dioxide tagged with up to 14 helium atoms, HeN–HOCO+. The first atom preferentially binds to the proton and results in a substantial redshift of 44 cm−1 for the OH stretching vibration, while the stepwise attachment of additional atoms up to N = 7 causes small and progressive blueshifts, which are attributed to the gradual formation of a ring of helium around the carbon atom. The methodology described herein offers a new route to obtain IR spectra of He-tagged ions and provides an insight into ion-solvent interactions at the molecular level.
Hydrodynamic correlations of viscoelastic fluids by multiparticle collision dynamics simulations
Authors: Toneian David , Kahl Gerhard , Gompper Gerhard , Winkler Roland G.
Published: November 2019

The emergent fluctuating hydrodynamics of a viscoelastic fluid modeled by the multiparticle collision dynamics (MPC) approach is studied. The fluid is composed of flexible, Gaussian phantom polymers that interact by local momentum-conserving stochastic MPCs. For comparison, the analytical solution of the linearized Navier-Stokes equation is calculated, where viscoelasticity is taken into account by a time-dependent shear relaxation modulus. The fluid properties are characterized by the transverse velocity autocorrelation function in Fourier space as well as in real space. Various polymer lengths are considered—from dumbbells to (near-)continuous polymers. Viscoelasticity affects the fluid properties and leads to strong correlations, which overall decay exponentially in Fourier space. In real space, the center-of-mass velocity autocorrelation function of individual polymers exhibits a long-time tail, independent of the polymer length, which decays as t−3/2, similar to a Newtonian fluid, in the asymptotic limit t → ∞. Moreover, for long polymers, an additional power-law decay appears at time scales shorter than the longest polymer relaxation time with the same time dependence, but negative correlations, and the polymer length dependence L−1/2. Good agreement is found between the analytical and simulation results.
Mechanical properties and energy development characteristics of impact-prone coal specimens under uniaxial cyclic loading
Authors: Du Weisheng , Zhang Kexue , Sun Huan
Published: November 2019

Energy is the intrinsic driving factor of rock dynamic failure. In this paper, the mechanical properties and energy development characteristics of impact-prone coal are studied. The stress and strain data and the acoustic emission (AE) signals of the impact-prone coal specimens are obtained by conducting cyclic loading-unloading tests. The elastic modulus deterioration rate is defined to describe the deterioration of the mechanical properties of the specimens during the loading process. The calculation results show that the elastic modulus deterioration rate of the impact-prone coal specimens during the cyclic loading process is as low as 3%. The AE monitoring results show that the AE signal is rare in the loading-unloading cycle before failure, and a large number of AE signals are generated at the failure moment. The stress-strain data are used to analyze the energy storage and distribution law of the loading process of impact-prone coal specimens. The results show that the input energy density increases nonlinearly with the increase of the load, and the input energy is mostly stored in the rock as elastic strain energy. The dissipative energy density is linear with the axial load. The impact-prone coal specimens have a strong ability to store elastic energy, and the precursor of damage and failure is not obvious. The study in this paper reveals the cause of the impact-prone coal easily induced to coal bursts from the energy point of view.
New time-resolved photoemission microscopy setup pushes resolution limits
Authors: Kim Meeri
Published: November 2019

New state-of-the-art setup for time-resolved photoemission microscopy (TR-PEEM) measurements over a broad wavelength range at high temporal and spatial resolution.
Total temperature affects hypersonic boundary layer transition
Authors: Patrick Chris
Published: November 2019

Simulations of a hypersonic sharp cone find that total temperature should be considered in wind tunnel studies of boundary layer transition.
Exploring fire response to high wind speeds: fire rate of spread, energy release and flame residence time from fires burned in pine needle beds under winds up to 27 ms−1
Authors: Butler Bret , Quarles Steve , Standohar-Alfano Christine , Morrison Murray , Jimenez Daniel , Sopko Paul , Wold Cyle , Bradshaw Larry , Atwood Loren , Landon Justin , O'Brien Joseph , Hornsby Benjamin , Wagenbrenner Natalie , Page Wesley
Published: November 2019

The relationship between wildland fire spread rate and wind has been a topic of study for over a century, but few laboratory studies report measurements in controlled winds exceeding 5ms−1. In this study, measurements of fire rate of spread, flame residence time and energy release are reported for fires burning under controlled atmospheric conditions in shallow beds of pine needles subject to winds ranging from 0 to 27ms−1 (measured 5m above ground level). The data suggested that under constant flow conditions when winds are less than 10ms−1, fire rate of spread increases linearly at a rate of ~3% of the wind speed, which generally agrees with other laboratory-based models. When wind speed exceeds 10ms−1, the fire rate of spread response to wind remains linear but with a much stronger dependence, spreading at a rate of ~13% of the wind speed. Radiative and convective heating correlated directly to wind speed, with radiant heating increasing approximately three-fold as much as convective heating over the range of winds explored. The data suggested that residence time is inversely related to wind speed and appeared to approach a lower limit of ~20s as wind exceeded 15ms−1. Average flame residence time over the range of wind speeds was nominally 26s.
Royal jelly reduces depression-like behavior through possible effects on adrenal steroidogenesis in a murine model of unpredictable chronic mild stress
Authors: Iegaki Noriyuki , Narita Yukio , Hattori Noriko , Hirata Yoko , Ichihara Kenji
Published: November 2019

Royal jelly (RJ) is used as a dietary supplement for human health promotion. Recently, a clinical trial has reported that RJ improved mental health. The present study was conducted to experimentally support the clinical effect of RJ on mental health and to further elucidate the mechanisms of action of RJ. RJ and an ethanol extract of RJ, which contains fatty acids but not proteins, inhibited an unpredictable chronic mild stress (UCMS)-induced increase in immobility time, a depression-like behavior, in the tail suspension test. DNA microarray analysis of the adrenal grand revealed that the expression of genes involved in cholesterol metabolism was up-regulated in response to UCMS exposure and that RJ suppressed expression of genes related to cholesterol synthesis and transport. These results suggested that RJ improves stress-induced depression-like behavior by regulating adrenal steroidogenesis and that fatty acids contained in RJ partly contribute to the antidepressant effect of RJ.
Isolation of four xylanases capable of hydrolyzing corn fiber xylan from Paenibacillus sp. H2C
Authors: Hagiwara Yusuke , Mihara Yasuhiro , Sakagami Koichi , Sagara Ryuta , Bat-Erdene Undramaa , Yatsunami Rie , Nakamura Satoshi
Published: November 2019

Corn fibre xylan (CX) shows high resistance to enzymatic hydrolysis due to its densely decorated side chains. To find enzymes capable of hydrolyzing CX, we isolated a bacterial strain (named H2C) from soil, by enrichment culture using non-starch polysaccharides of corn as the sole carbon source. Analysis based on the 16S rRNA sequence placed strain H2C within genus Paenibacillus. Enzymes were purified from supernatant of culture broth of strain H2C based on solubilizing activities toward CX. Four enzymes, Xyn5A, Xyn10B, Xyn11A, and Xyn30A, were successfully identified, which belong to glycoside hydrolase (GH) families, 5, 10, 11, and 30, respectively. Phylogenetic analysis classified Xyn5A in subfamily 35 of GH family 5, a subfamily of unknown function. Their activities toward beechwood xylan and/or wheat arabinoxylan indicated that these enzymes are β-1,4-xylanases. They showed high solubilizing activities toward a feed material, corn dried distiller’s grains with solubles, compared to five previously characterized xylanases.

Abbreviations : CX: corn fibre xylan; DDGS: corn dried distiller’s grains with solubles
Electrical properties of graphene/In2O3 bilayer with remarkable uniformity as transparent conducting electrode
Authors: Lee Sangbong , Kim Minsu , Cho Seong-Yong , Lee Do-Joong , Kim Hyun-Mi , Kim Ki-Bum
Published: November 2019

A graphene/In2O3 bilayer (termed as GI-bilayer) is proposed as a transparent conducting electrode with remarkably improved areal-uniformity. To fabricate this new structure, an In2O3 layer with a thickness of less than 50 nm was grown by atomic layer deposition and then a graphene layer was grown by chemical vapor deposition and subsequently transferred onto the as-grown In2O3 layer. Electrical and optical properties of the GI-bilayer were systematically studied to verify effects of the underlying In2O3 layer. Hall measurements and following analysis showed a conductance enhancement of the GI-bilayer owing to p-type doping of graphene. Specifically, Raman analysis and ultraviolet photoelectron spectroscopy were performed to prove p-type doping of the graphene in the GI-bilayer. In addition, the GI-bilayer exhibited the significantly improved uniformity of the sheet resistance compared to that of a conventional monolayer of graphene. There was a duality on the role of the In2O3 underlayer in the GI-bilayer. It acted as a dopant layer to the graphene and lowered the sheet resistance from 863 to 510 Ω/sq as well as compensated microscale defects on graphene. More importantly, the In2O3 underlayer resulted in the extremely reduced standard deviation of sheet resistance from 150 to 7.5 Ω/sq over the area of 49 cm2.
Heralded entanglement purification protocol using high-fidelity parity-check gate based on nitrogen-vacancy center in optical cavity*
Authors: Lu Lu-Cong , Wang Guan-Yu , Ren Bao-Cang , Zhang Mei , Deng Fu-Guo
Published: November 2019

The decoherence of entangled states caused by the noisy channel is a salient problem for reducing the fidelity of quantum communication. Here we present a heralded two-photon entanglement purification protocol (EPP) using heralded high-fidelity parity-check gate (HH-PCG), which can increase the entanglement of nonlocal two-photon polarization mixed state. The HH-PCG is constructed by the input-output process of nitrogen-vacancy (NV) center in diamond embedded in a single-sided optical cavity, where the errors caused by the imperfect interaction between the NV center-cavity system and the photon can be heralded by the photon detector. As the unwanted components can be filtrated due to the heralded function, the fidelity of the EPP scheme can be enhanced considerably, which will increase the fidelity of quantum communication processing.
Room temperature non-balanced electric bridge ethanol gas sensor based on a single ZnO microwire*
Authors: Li Yun-Zheng , Feng Qiu-Ju , Shi Bo , Gao Chong , Wang De-Yu , Liang Hong-Wei
Published: November 2019

In this paper, ultra-long and large-scaled ZnO microwire arrays are grown by the chemical vapor deposition method, and a single ZnO microwire-based non-balanced electric bridge ethanol gas sensor is fabricated. The experimental results show that the gas sensor has good repeatability, high response rate, short response, and recovery time at room temperature (25 °C). The response rate of the gas sensor exposed to 90-ppm ethanol is about 93%, with a response time and recovery time are 0.3 s and 0.7 s respectively. As a contrast, the traditional resistive gas sensor of a single ZnO microwire shows very small gas response rate. Therefore, ethanol gas sensor based on non-balanced electric bridge can obviously enhance gas sensing characteristics, which provides a feasible method of developing the high performance ZnO-based gas sensor.
Formation of salinity and density vertical stratification of the Black sea
Authors: Korotaev G K
Published: November 2019

A simple model of the haline and density stratification evolution in the cylindrical rotating basin under the influence of buoyancy fluxes through the side border is proposed in the work based on the dimension analysis. The model is based on the assumption that the sharp pycnocline and two different circulation cells in the vertical plane above and below pycnocline. The model shows that the typical time of vertical circulation cell modification is determined by the inertia of the main body of waters in the basin. Also under fixed ambient conditions, one should expect pycnocline sharpening and increased intensity of vertical circulation cells over time. The model application to describe the climatic changes of the Black Sea haline stratification is discussed. It is asserted that the response of a marine basin to changes in the external conditions depends significantly on the inertia of a main water body. It is noted that this result is of importance not only for the Black Sea, but also for the World Ocean. This effect explains the slow change in the meridional heat transport even in case of considerable variations of deep convection at high latitudes.
Heat transfer and structure of a turbulized flow in a converging channel
Authors: Davletshin I A , Goltsman A E , Paereliy A A
Published: November 2019

The paper deals with experimental studies of convective heat transfer and kinematic flow structure in a plane converging channel. Different turbulence intensities were generated by a variety of arrangements at the channel inlet. Distributions of heat transfer coefficient over the wall of the converging channel were obtained in different regimes of the air flow. Optical measurements yielded the profiles of hydrodynamic parameters at characteristics locations.
The effect of intermittency on the transition to turbulence in the jets
Authors: Lemanov V V , Lukashov V V , Sharov K A
Published: November 2019

For the outflow of jets of various gases from long round tubes, the mode of transition to turbulence through the intermittency mechanism in the near field of the jet was experimentally detected for the first time. This mode is realized in the range of Reynolds numbers of 1900-3200, when inside the jet source, a laminar-turbulent transition occurs in the tube. The reasons of intermittency are turbulent spots (puff). These localized turbulent structures are formed inside the pipe, have a length of about 10-30 pipe diameters in the jet and occupy the entire transverse size of the jet flow.
Hydrodynamic analysis of the efficiency of thermochemical methods at deposits with complicated development conditions
Authors: Dieva N N , Kravchenko M N , Muradov A V , Lishchuk A N , Evtyukhin A V
Published: November 2019

In this paper we will focus on a promising technology of thermochemical treatment using the energy of the exothermic reaction of the interaction of two inorganic salts pumped into the reservoir in the form of an aqueous solution. The technology is environmentally safe and effective for intensification of production at low-yield wells of “old” layers and for low-permeable layers of unconventional high-viscosity oil. The authors created a mathematical model of the process and conducted a series of numerical studies that form the basis of field experiments to test technology at various fields in Russia. This work was supported by the RFBR grant No. 19-07-00433 A.
Some peculiarities of superheated water flow in contracting-expanding nozzles and their influence on droplet dimension distribution in an atomized water plume
Authors: Zalkind V I , Zeigarnik Yu A , Nizovskiy V L , Nizovskiy L V , Schigel S S
Published: November 2019

New calculation data on superheated metastable water flow in atomizing Laval type nozzles is presented. The calculating model is discussed on the assumption of predominating nucleation role in liquid atomization. The Mach number variation is presented for diffuser part of the nozzle taking into account the sound velocity variation in a vapor-liquid system. The new criterion, based upon experimental and calculating data, which determines the reaching of full-flashing regime, is proposed for contracting-expanding nozzles. The submicron mass fraction is considered to be a function of dimensionless parameter, which is the critical radius bubble surface tension energy ratio to chemical potential of phase transition for critical bubble radius at certain pressure drop.
Study of self-preservation of gas hydrates in suspensions in oils
Authors: Skiba S S , Yu Manakov A
Published: November 2019

Impact of different parameters on the decomposition rates of hydrate at negative temperatures with depressurisation method has been studied. In previous work it was demonstrated that decomposition rates of hydrates suspensions in oil at static conditions can be limited by the self-preservation phenomenon. Our experimental research shows that appearance of self-preservation depends on many parameters such as components composition of oil, presence of shear in the system while decomposing hydrates and probably on the history of the sample.
Influence of inorganic salt on the characteristics of oxidation, ignition and combustion of bituminous coal
Authors: Larionov K B , Mishakov I V , Slyusarsky K V
Published: November 2019

The processes of oxidation, ignition and combustion of bituminous coal containing 5 wt.% of activating agent (Cu(NO3)2) was studied. The experiment was performed using high-speed video recording of the combustion process of the researched coals in combustion chamber at a temperature of 700°C in the air at atmospheric pressure. Analytical assessment of the characteristics of ignition and combustion processes of the researched coals was carried out based on the obtained results. It was established that addition of Cu(NO3)2 promoter leads to a significant decrease of the time characterizing the delay in the beginning of coal ignition (in 2 times). Effect of the activating additive was also expressed in formation of flame during coal combustion at the stage of volatile substances separation with periodic formation of characteristic flashes formed as a result of decomposition of copper nitrate in the pores of the carbon matrix. This contributed to intensification of the release process of relatively large volume of combustible gases. The obtained results were compared with previously obtained data of the oxidation process of these coals with activating additives of copper salts by thermogravimetric analysis.
Numerical simulation of hydrogen combustion in oxidizer supersonic flow in flowpaths of various configurations
Authors: Kukshinov N V , Batura S N
Published: November 2019

The paper deals with the numerical simulation of the combustion of a hydrogen-air mixture in a supersonic flow in channels of various configurations. Axisymmetric and plane type flows are considered. The simulation is based on solving the complete system of Navier-Stokes equations with closure using a turbulence model and detailed chemical kinetics. To validate the results, Beach-Evans-Schexnayder and Burrows-Kurkov experimental data are used. The influence of various kinetic mechanisms, models of turbulence, and boundary conditions on the solution obtained is considered. The boundaries of the methods are shown.
Numerical simulation of the transition to turbulence in subsonic and transonic flows
Authors: Poplavskaya T V , Boiko A V , Demyanko K V , Kirilovskiy S V , Nechepurenko Y M
Published: November 2019

The goal of the paper is to determine the position of the laminar-turbulent transition in subsonic and transonic two-dimensional boundary layers on an airfoil with the use of the a laminar-turbulent transition module based on the eN-method and using the results of numerical simulations of the laminar flow around the model performed by the ANSYS Fluent software. The combined operation of the CFD software and the laminar-turbulent transition module is illustrated by an example of the air flow around the NASA-SR-0410 supercritical airfoil. It is demonstrated that the predicted and experimental data on the laminar-turbulent transition are in good agreement.
The parametric studies of the effect of synthetic jets on the distribution of heat fluxes in a flat model channel
Authors: Belova V G , Stepanov V A , Yu Chirkov A
Published: November 2019

The results of the calculation of the flow on the plate under the influence of synthetic jets using the RANS and URANS methods are presented. The dependence of the parameters of synthetic jets on the distribution of heat flux into the wall on the plate is shown.
Main features of application of liquid crystal composites for the near-wall flow diagnostics
Authors: Zharkova G M , Kovrizhina V N
Published: November 2019

In the work the special aspects of panoramic temperature and/or shear stress diagnostics by liquid crystals are considered. Some metrological characteristics of two types of LC composites on the basis of cholesterics and nematics are discussed. The temperature and shear stress hue sensitivity are analyzed. The examples of application are presented.
Problems of heat flux measurement by means of IR camera under a pulse impact on a sample
Authors: Bountin D A , Shiplyuk M A
Published: November 2019

A problem of temperature measurements under a pulse impact on a sample in a case of short-time wind tunnel experiments has been studied. Large errors in temperature definition of the sample wall leads to large errors in heat flux calculation, based on temperature change. The hypothesis on the reason of this error has been examined in the paper and the method of deconvolution has been proposed to improve heat flux calculation.
Developing the complex method for flow investigation in a hydro-turbine model using laser anemometry and video recording
Authors: Kabardin I K , Meledin V G , Naumov I V , Anikin Yu A , Pavlov V A , Semenov D O
Published: November 2019

The complex technique using laser and video equipment in test conditions at the setups of the Laboratory of water turbines of the Leningrad Metal Plant has been developed to conduct laser measurements of velocity fields and video recording of cavitation phenomena based on the integration of the laser systems (“LAD - 0xx" and “Track-07 S”), created at the Kutateladze Institute of Thermophysics SB RAS (IT SB RAS) and JSC “IOIT.” The Doppler anemometer allowed to achieve experimental distribution of the circumferential, axial, and radial velocity components at each point along the radius of the suction tube cone section of test experimental setup which has give information about vortex structure in suction turbine. The developed PTV method is described. The investigation of cavitation behind the turbine blade at test setup at velocities of 8-10 m/s is presented.
Determining experimental applicability limits of Spalart-Almares turbulent model and Reynolds stresses transfer model at mass transfer intensification in rotary-divergent controlled flows
Authors: Kabardin I K , Yavorsky N I , Meledin V G , Kh Pravdina M , Gordienko M R , Ezendeeva D P , Kakaulin S V , Usov E V , Klimonov I A , Krotov S V , Bakakin G V , Kabardin A K , Yu Sadbakov O
Published: November 2019

This problem can arise in mechanics, chemistry and catalysis in the mass transfer intensification. The mass transfer characteristics were experimentally analyzed in a controlled rotary-divergent flow. The laser Doppler anemometer was used for turbulent mass transfer diagnostics. The experimental investigation was used to verify the numerical calculations. The numerical simulation has shown the presence of a near-wall jet after a rotary device and the reverse flow zones formation. The model of Reynolds stress transfer adequately describes the flow in range of flow rates from 50 to 250 n.m3/h. The Spallart-Almares turbulence model fails to adequately describe the flow at all flow rates.
Experimental study of temperature dependence of drilling fluids viscosity with nanoparticles
Authors: Mikhienkova E I , Minakov A V , Matveev A V , Pryazhnikov M I
Published: November 2019

This research is focused on the dependence of viscosity of water-based drilling fluid modified by nanoparticles on temperature. Silicon oxide of 10 nm size was used as nanoparticles. The nanosuspensions were prepared for nanoparticle concentrations from 0.25 to 3 wt%. An aqueous solution of bentonite with a mass fraction of 5 % was used as a base drilling fluid. Rheological studies were conducted at varying temperatures (25, 40, 55 and 80 °C). The dependences of the effective viscosity of these suspensions on the concentration of nanoparticles and temperature have been obtained.