bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure and dynamics of catalytically competent but labile paramagnetic metal-hydrides: the Ti(iii)-H in homogeneous olefin polymerization
Authors: Salvadori Enrico , Chiesa Mario , Buonerba Antonio , Grassi Alfonso
Published: September 2020

Catalytically competent titanium-hydrides are reactive and difficult to isolate. We use EPR spectroscopy to define the electronic and geometrical structures as well as dynamics of an open-shell Ti-H active in syndiospecific olefin polymerization.
Aging of living polymer networks: a model with patchy particles
Authors: Iubini Stefano , Baiesi Marco , Orlandini Enzo
Published: September 2020

A novel model of patchy particles, mapped to micellar networks, bridges the gap between microscopic and macroscopic time scales (seconds) and unveils the presence of a very slow relaxation process with metastable states.
Iron clusters boosted performance in electrocatalytic carbon dioxide conversion
Authors: Wu Dongchuang , Wang Xinyue , Shi Linghao , Jiang Kaiyue , Wang Mengjia , Lu Chenbao , Chen Zhenying , Liu Pan , Zhang Jichao , Tranca Diana , Hou Yang , Chen Yu , Zhuang Xiaodong
Published: September 2020

The atomic interfaces of iron cluster sites can easily transform CO2to *COOH, resulting in excellent catalytic performance.
Distorted quantum dots enhance the efficiency of alkaline oxygen electrocatalysis
Authors: Zhang Xiaoyu , Fu Weiwei , Tian Wu , Wan Jin , Zhang Han , Wang Yu
Published: September 2020

Scattering quantum dots bind chemically to substrate is considered as an efficient kind of strategy to modulate electronical construction and catalytic properties in the research of electrocatalytic materials.
Block copolymer [(l-GluA-5-BE)-b-(l-AspA-4-BE)]-based nanoflower capsules with thermosensitive morphology and pH-responsive drug release for cancer therapy
Authors: Amgoth Chander , Chen Shuai , Malavath Tirupathi , Tang Guping
Published: September 2020

Herein, the synthesis of an amino-acid-based di-block copolymer (di-BCP) in-between an l-glutamic acid-5-benzyl ester and L-aspartic acid-4-benzyl ester [(l-GluA-5-BE)-b-(l-AspA-4-BE)] has been reported.
Semiconducting CuxNi3−x(hexahydroxytriphenylene)2framework for electrochemical aptasensing of C6 glioma cells and epidermal growth factor receptor
Authors: Guo Chuanpan , Li Zhenzhen , Duan Fenghe , Zhang Zhihong , Marchetti Fabio , Du Miao
Published: September 2020

A 2D CuNi metal–organic framework (MOF) named CuxNi3−x(HHTP)2was synthesized as a sensitive scaffold to adsorb aptamer strands for the electrochemical detection of living C6 glioma cells and epidermal growth factor receptor (EGFR).
Conductive polymer supported and confined iron phosphide nanocrystals for boosting the photocatalytic hydrogen production of graphitic carbon nitride
Authors: Li Tao , Wang Kai , Fang Qi-Tao , Zhang Yu , Wang Bo , Li Rui , Lin Ye-Zhan , Liu Ke-Cheng , Xie Hai-Quan , Li Kui
Published: September 2020

A green redox relay reaction between FeCl3 and pyrrole  monomer was developed for synthesizing g-C3N4–PPy–FeP with a hydrogen production activity of 6 and 20 times larger than that of g-C3N4 singly loaded separately with PPy and FeP.
Ladder-type bithiophene imide-based organic semiconductors: understanding charge transport mechanisms in organic field effect transistors
Authors: Harbuzaru Alexandra , Arrechea-Marcos Iratxe , Scaccabarozzi Alberto D. , Wang Yingfeng , Guo Xugang , Caironi Mario , López Navarrete J. Teodomiro , Ruiz Delgado M. Carmen , Ponce Ortiz Rocío
Published: September 2020

Different charge transport mechanisms at the device interface are found for a series of ladder-type semiconductors with increasing chain length.
Sinorhizobium melilotiYrbA binds divalent metal cations using two conserved histidines
Authors: Roret Thomas , Alloing Geneviève , Girardet Jean-Michel , Perrot Thomas , Dhalleine Tiphaine , Couturier Jérémy , Frendo Pierre , Didierjean Claude , Rouhier Nicolas
Published: September 2020

Sinorhizobium meliloti is a nitrogen-fixing bacterium forming symbiotic nodules with the legume Medicago truncatula. S. meliloti possesses two BolA-like proteins (BolA and YrbA), the function of which is unknown. In organisms where BolA proteins and monothiol glutaredoxins (Grxs) are present, they contribute to the regulation of iron homeostasis by bridging a [2Fe–2S] cluster into heterodimers. A role in the maturation of iron–sulfur (Fe–S) proteins is also attributed to both proteins. In the present study, we have performed a structure–function analysis of SmYrbA showing that it coordinates diverse divalent metal ions (Fe2+, Co2+, Ni2+, Cu2+ and Zn2+) using His32 and His67 residues, that are also used for Fe–S cluster binding in BolA–Grx heterodimers. It also possesses the capacity to form heterodimers with the sole monothiol glutaredoxin (SmGrx2) present in this species. Using cellular approaches analyzing the metal tolerance of S. meliloti mutant strains inactivated in the yrbA and/or bolA genes, we provide evidence for a connection of YrbA with the regulation of iron homeostasis. The mild defects in M. truncatula nodulation reported for the yrbA bolA mutant as compared with the stronger defects in nodule development previously observed for a grx2 mutant suggest functions independent of SmGrx2. These results help in clarifying the physiological role of BolA-type proteins in bacteria.
Two‐tier trading strategy design for spectrum allocation in heterogeneous cognitive radio networks
Authors: Huang Xiaowen , Zhang Wenjie , Yang Jingmin , Yang Liwei , Yeo Chai Kiat
Published: September 2020

The heterogeneous network structure is a promising paradigm to improve the quality of service across the entire network. Nevertheless, such a structure is challenging due to the presence of multiple‐tier secondary users (SUs). In this study, the authors investigated the effect of spectrum allocation in heterogeneous cognitive radio networks with a primary network and two‐tier secondary networks, and proposed a two‐tier spectrum trading strategy which includes two trading processes. In Process One, they model the spectrum trading as a monopoly market, where the primary spectrum owner (PO) acts as the monopolist and the first‐tier secondary users (FSUs) act as the buyers. They design an optimal quality‐price contract to maximise the utility of PO, and the FSUs will choose the spectrum with appropriate quality and price to enhance their satisfaction. In Process Two, spectrum trading is modelled as a multi‐seller, multi‐buyer market. The dynamic behaviour of second‐tier SUs is studied using the theory of evolution game, while the competition among FSUs is analysed via a non‐cooperative game where the Nash equilibrium is considered as the solution. The existences of the optimal contract, evolutionary equilibrium and Nash equilibrium are demonstrated in the performance evaluation.
Input–output dynamical stability analysis for cyber‐physical systems via logical networks
Authors: Zhao Guodong , Li Haitao , Hou Ting
Published: September 2020

In this study, the authors investigate the input–output dynamical stability of cyber‐physical systems, and obtain some new results. In the beginning, they proposed an algorithm to convert the finite systems into the logical networks, and the inherent relationship between them is analysed. Secondly, the aforementioned results are applied to the analysis for the robustness of infinite systems. Thirdly, the given cyber‐physical system is converted to a logical network with the same robustness and the robustness of the cyber‐physical system is analysed. In the end, an illustrative example shows the effectiveness of the obtained results.
Strong, omnidirectional radar backscatter from subwavelength, 3D printed metacubes
Authors: Powell Alex W. , Ware John , Beadle Joseph G. , Cheadle David , Loh Tian Hong , Hibbins Alastair P. , Sambles J. Roy
Published: September 2020

Metallic metacubes formed of six metal plate faces connected via a metal jack are shown to backscatter microwave radiation extremely powerfully. Experimental radar scattering cross‐section (RCS) data from three‐dimensional (3D) printed samples agrees very well with numerical model predictions, showing a monostatic RCS of 15 times the geometric cross‐section. The principal resonance of the metacubes demonstrates near‐complete independence of the incident angle or polarisation of the radiation, making the metacube an omnidirectional scatterer. The metacubes are fabricated via additive manufacturing from metal‐coated polymer, and are extremely lightweight, making them excellent candidates for improving the radar return signals from small objects such as drones and cubesats.
The contribution of discrete sources to the sky temperature at 144 MHz
Authors: Hardcastle M. J. , Shimwell T. W. , Tasse C. , Best P. N. , Drabent A. , Jarvis M. J. , Prandoni I. , Röttgering H. J. A. , Sabater J. , Schwarz D. J.
Published: September 2020

In recent years, the level of the extragalactic radio background has become a point of considerable interest, with some lines of argument pointing to an entirely new cosmological synchrotron background. The contribution of the known discrete source population to the sky temperature is key to this discussion. Because of the steep spectral index of the excess over the cosmic microwave background, it is best studied at low frequencies where the signal is strongest. The Low-Frequency Array (LOFAR) wide and deep sky surveys give us the best constraints yet on the contribution of discrete extragalactic sources at 144 MHz, and in particular allow us to include contributions from diffuse, low-surface-brightness emission that could not be fully accounted for in previous work. We show that, even with these new data, known sources can still only account for around a quarter of the estimated extragalactic sky temperature at LOFAR frequencies.
Measurement and research of environmental natural radiation dose
Authors: Wan Zongxi
Published: September 2020

The living environment of human beings is being affected by various types of radiation. Among them, natural radiation has the largest dose. If the dose of natural radiation exceeds a certain threshold level, people will face health risks on multiple fronts. In this work, researchers measured the air-absorbed dose rate at 1 meter above different surface environments on campus and estimated the effective dose equivalent of environmental gamma radiation to the residents. Experiments and analyses show that the radiation level on campus was evaluated based on the measurements. The order of the amount of the radiation dose rate is granite pavement > cement pavement > asphalt ground. According to the experiments, the radiation content of external exposure in the campus is already slightly higher than the limit, i.e. 1mSv/y.
Locomotive Noise Reduction
Authors: Nesterov Nikita , Bykov Aleksei
Published: September 2020

This paper presents the results of the investigation of the noise characteristics of the dual-voltage mainline electric locomotive. The study identified noise levels generated by the locomotive equipment that violate regulations. The analysis of points, where the noise is above regulations, indicated the primary source of the elevated noise is the operation of the traction transformer. We proposed installing a noise barrier below the locomotive body to reduce noise and bring the locomotive in compliance with the noise regulations. This solution allowed reducing the locomotive noise and ensure its compliance with regulations.
Classification of gas reduction valve silencers at TPP gas distribution points
Authors: Skvortsov Vitaliy , Tupov Vladimir B.
Published: September 2020

Gas distribution points (GDP) at TPPs are sources of intense noise. Results of noise experimental measurements originating from TPP GDP demonstrate that the sound level at a distance of 10 m could reach 110 dBA. Gas reduction valves are the source of noise in GDP. Noise emission characteristic of the gas reduction valves depends on their geometric and design parameters. To reduce the noise propagating in a low-pressure gas pipeline from gas reduction valves, various types of noise silencers are used. This paper presents results of noise experimental measurements in the vicinity of the GDP buildings at various energy enterprises. Overview and classification of silencers by various manufacturers used at TPP GDPs are provided.
Sound Scattering Properties of Surfaces with Diffusers
Authors: Lavrova Marina , Kanev Nikolay
Published: September 2020

This article compares the values of the normal scattering coefficient measured in a model experiment for two types of diffusers placed on a rigid surface. Wooden diffusers of cubic and pyramidal shapes were tested in a scale model of a room with dimensions of 0.7x0.4x0.4 m. Sound decay curves were measured at frequencies of 4kHz and 8kHz. Two large walls were covered with a porous absorber, on the third, in certain combinations, the investigated diffusers with a characteristic size of 3.5 cm were placed, the number of which varied from 0 to 29. The idea of the applied method is that the sound decay curve in a room with a non-diffuse sound field depends significantly from the scattering properties of surfaces. The decay curve was measured with different numbers of the diffusers on the test wall, which made it possible to determine the influence of the shape of the diffusers and their number on the value of the normal scattering coefficient. According to the results of the measurements a high scattering ability of cubic elements was revealed in comparison with pyramidal ones.
Experimental study of the effect of the design features of frame partitions on their sound insulation
Authors: Vasilyev Michael , Gerasimov Anatoly , Rud Nikita
Published: September 2020

This paper presents an experimental comparison of various multilayer frame-sheathing structures and describes the effect of their design features on their own sound insulation. The paper discusses the dependence of sound insulation on material and type of the frame, the amount and density of the filler, the number and type of facing layers, the presence of a damping layer and a divided base.
Sound propagation over underlying surface
Authors: Kulkina Valeriya , Komkin Alexandr
Published: September 2020

The features of noise emission, when its source is located above the underlying (reflecting) surface, have been considered. The main factor determining the pattern of sound pressure distribution in space is the interference between sound waves incident on this surface and reflected from it. The influence of the height of the noise source above the underlying surface, as well as the acoustic characteristics of this surface, on this process has been analyzed.
Approximation of the invariant distribution for a class of ergodic jump diffusions
Authors: Gloter A. , Honoré I. , Loukianova D.
Published: September 2020

In this article, we approximate the invariant distributionνof an ergodic Jump Diffusion driven by the sum of a Brownian motion and a Compound Poisson process with sub-Gaussian jumps. We first construct an Euler discretization scheme with decreasing time steps. This scheme is similar to those introduced in Lamberton and PagèsBernoulli8(2002) 367-405. for a Brownian diffusion and extended in F. Panloup,Ann. Appl. Probab.18(2008) 379-426. to a diffusion with Lévy jumps. We obtain a non-asymptoticquasiGaussian (asymptotically Gaussian) concentration bound for the difference between the invariant distribution and the empirical distribution computed with the scheme of decreasing time step along appropriate test functionsfsuch thatf−ν(f) is a coboundary of the infinitesimal generator.
Safewards: Unser Weg zu einem sicheren Ort
Authors: Lauterbach Ralf , Schwarz Markus , Pleitgen Andrea
Published: September 2020

Das Safewards-Modell etabliert sich in den Psychiatrien in Deutschland und wird von den Pflegenden gerne angenommen. In Ausgabe 3/20 erläuterte Anja Kuntz die Einführung des Konzepts im Pfalzklinikum Klingenmünster. Der vorliegende Artikel beschreibt die Einführung im Psychiatrischen Zentrum Nordbaden. Beide Kliniken sind ähnliche Wege gegangen, sie waren und sind zu diesem Thema eng vernetzt. Während bei Anja Kuntz die Interventionen im Vordergrund standen, fokussieren die Autoren dieses Artikels stärker die zur Einführung des Modells bereitgestellten personellen Ressourcen und die Partizipation der Stationsteams. Beide Artikel zusammengenommen sind ein Plädoyer dafür, dass bei der Umsetzung neuer Konzepte der Austausch und die Vernetzung über die eigene Klinik hinaus ein überaus sinnvoller Weg sein kann.
Integration immuntherapeutischer Ansätze in individuelle
Behandlungsansätze bei rezidivierten Kopf-Hals-Tumoren
Authors: Büntzel Jens
Published: September 2020

10–20% aller Kopf-Hals-Tumorpatienten erleiden ein lokales
oder lokoregionäres Rezidiv. Gute Ergebnisse haben hier lokale
Verfahren wie eine nochmalige Strahlentherapie, Resektion oder ablative
Chirurgie, inklusive der photodynamischen Therapie. Seit einigen Jahren
kommen auch Immuntherapeutika (Checkpoint-Inhibitoren, EGFR-Inhibitoren)
immer früher bei diesen Patienten zum Einsatz. Dies führt zu
wesentlichen längeren Krankheitsverläufen mit breiten
Kombinationsmöglichkeiten einerseits (Kasuistik 1), andererseits
sind neue Interaktionen zu beachten (Kasuistik 2). Insbesondere bei aktiven
Patienten mit diversen komplementärmedizinischen
Behandlungsansätzen müssen diese Wechselwirkungen kritisch
beachtet und hinterfragt werden.
Fixação percutânea sem enxerto ósseo para pseudartrose do escafóide
Authors: Belloti João Carlos , Vasconcelos Klebson Bruno Lopes , Raduan Neto Jorge , Okamura Aldo , Fernandes Marcela , de Moraes Vinícius Ynoe
Published: September 2020

Objetivo Descrever os resultados clínico-radiográficos de pacientes tratados por meio de fixação percutânea sem enxerto ósseo para pseudartrose do escafóide, com seguimento mínimo de seis meses.

Métodos Série de casos de uma amostra de conveniência de grupo de cirurgiões de mão com avaliação prospectiva.. Foram incluídos pacientes com diagnóstico de pseudartrose do escafóide (cintura ou polo proximal) com as seguintes características: mais de seis meses de histórico; radiografias demonstrando esclerose das bordas da pseudartrose, com reabsorção do foco de pseudartrose menor do que 4 mm (Slade & Gleissler I, II, III e IV), sem deformidade angular; e sem necrose do polo proximal pela ressonância magnética (RM).

Resultados Na avaliação com mais de seis meses, todas as pseudartroses estavam consolidadas e sem maiores complicações. Os resultados funcionais demonstraram boas pontuações nos questionários de disfunções do braço, ombro e mão (disabilities of the arm, shoulder and hand, DASH; n = 12; média: 6,9; desvio padrão [DP]: 2,1) e de avaliação do punho pelo paciente (patient-rated wrist evaluation, PRWE; n = 12; média: 7,97; DP: 1,5). Observou-se pouca dor residual de acordo com a escala visual analógica (EVA; n = 12; média: 0,71; DP: 0,2). Houve discreta diminuição da flexão (69 versus 59,1; p = 0,007), da extensão (62,4 versus 48,7; p = 0,001) e do desvio radial (29,6 versus 24.6; p = 0,014) em comparação ao lado contralateral.

Conclusões Nesta série, todos os casos estavam consolidados ao sexto mês de avaliação, com bom status funcional. Trata-se de uma opção promissora (menor demanda técnica e morbidade) para o tratamento da pseudartrose do escafóide. Estudos comparativos serão úteis para avaliar a efetividade da técnica com relação a outras opções.
Estudo prospectivo das lesões musculares em três temporadas consecutivas do Campeonato Brasileiro de Futebol
Authors: Margato Gabriel Furlan , Andrade Júnior Edilson Ferreira , Lara Paulo Henrique Schmidt , Pagura Jorge Roberto , Cohen Moisés , Arliani Gustavo Gonçalves
Published: September 2020

Objetivo Realizar uma avaliação prospectiva das lesões musculares ocorridas durante as partidas das séries A e B do Campeonato Brasileiro de Futebol Masculino dos anos de 2016 a 2018.

Métodos Estudo de coorte prospectivo com coleta de dados referentes às lesões musculares ocorridas durante os jogos oficiais da primeira e segunda divisões do Campeonato Brasileiro de Futebol Masculino nas temporadas de 2016, 2017 e 2018.

Resultados O número total de lesões musculares foi de 577 ao longo das 3 temporadas, havendo uma redução gradual e anual na incidência delas (219 lesões em 2016, 195 em 2017, e 163 em 2018), com diferença estatística significativa entre os anos de 2016 e 2018. As lesões musculares representaram aproximadamente 35% de todas as lesões. A incidência das lesões musculares foi 7,66 para cada 1.000 horas de jogo. Nas 3 temporadas (2016 a 2018), a mais comum foi a lesão muscular dos isquiotibiais (41,1%, 40,5% e 33,7%, respectivamente). Os laterais foram os mais acometidos, e a escala de severidade de lesão mais comum foi a moderada (8 a 28 dias). O momento da partida com maior incidência de lesões foi no período entre 61 e 75 minutos, com um índice de 19,9%, não havendo diferença estatística em relação aos demais períodos de jogo.

Conclusão Houve uma incidência de lesões musculares de 7,7 lesões/1.000 h, e ocorreram predominantemente nos jogos em casa, em defensores (laterais e zagueiros), com idade média de 28 anos, envolvendo principalmente a musculatura isquiotibial, com tempo médio de afastamento moderado (8 a 28 dias).
Análise clínica e radiológica do resultado placa ponte versus fixador externo na fratura cominutiva do rádio distal
Authors: Carula Beatriz Canhoto , Pereira Matheus da Silva , Ferreira Ana Paula Bonilauri , Ayzemberg Henrique , Steglich Valdir , Stangarlin Tiago Salati
Published: September 2020

Objetivo Avaliar e comparar os resultados clínicos e radiológicos de pacientes com fraturas cominutivas distais do rádio tratados com fixador externo ou placa ponte dorsal.

Métodos Foram analisados 45 pacientes, sendo 18 tratados com fixador externo, e 25, com placa ponte dorsal, após 1 ano de pós-operatório. Aplicou-se uma escala analógica de dor e o questionário Disabilities of the Arm, Shouder and Hand (DASH), além de análise radiográfica, da avaliação de força, e da amplitude de movimento. As análises estatísticas foram realizadas utilizando o teste qui-quadrado e o teste não paramétrico de Mann-Whitney.

Resultados A fratura foi mais comum em mulheres acima de 60 anos por queda do mesmo nível. Ambos os métodos demonstraram resultados funcional e radiológico similares. A infecção foi mais prevalente com o uso do fixador externo, mas a força de preensão residual foi melhor. Neuropatia simpático-reflexa foi mais comum com o uso da placa ponte dorsal.

Conclusão Não houve consenso da superioridade de um método em relação ao outro em nossa análise. Cada um dos métodos apresenta vantagens e desvantagens, mas ambos mostraram resultados bons e semelhantes. A escolha do tratamento deve ser atribuída ao perfil do trauma, às condições clínicas do paciente, à experiência do profissional, e à disponibilidade de materiais.
Verbal and Nonverbal Mismatch Negativity in Children with Typical Development: Variables Analysis
Authors: de Souza Amália El Hatal , Biaggio Eliara Pinto Vieira
Published: September 2020

Introduction Mismatch negativity (MMN) is a promising instrument for the investigation of different auditory disorders, as it does not need behavioral responses.

Objective To analyze the influence of the ear, gender and age variables in the MMN in children with typical development; and to compare the different measures of this potential, using verbal and nonverbal stimuli in the sample studied, providing reference values.

Methods Observational, descriptive, cross-sectional, quantitative study, with 23 children, aged from 5 to 11 years and 11 months old, divided by age group. Mismatch negativity was performed using verbal and nonverbal stimuli, and the data was analyzed by means of the statistical Student t-test.

Results No significant differences were noted for the ear, gender and age variables in the MMN with both stimuli. There were significant differences for the latency, duration and area variables when the stimuli were compared. The reference values established for nonverbal stimuli were: latency 249.8 milliseconds, amplitude 2.28 µv, duration 82.97 milliseconds, and area 137.3 microvolt x microseconds (μVx μs); as for the verbal stimuli, they were: latency 265.3 milliseconds, amplitude - 2.82 µv, duration 110.5 milliseconds, and area 225.5 microvolt x microseconds (μVx μs).

Conclusion The variables studied did not influence the recordings of the MMN. Latency, duration and area of the MMN with verbal stimuli were higher. It was possible to furnish reference values for children with typical development in the age group studied.
Management of Early Glottic Cancer Treated by CO2 Laser According to Surgical-Margin Status: A Systematic Review of the Literature
Authors: Verro Barbara , Greco Giuseppe , Chianetta Enzo , Saraniti Carmelo
Published: September 2020

Introduction Transoral laser microsurgery (TLM) is the treatment of choice for Tis-T2 squamous cell glottic carcinomas due to its advantages compared with open surgery and radiotherapy. However, the CO2 laser beam causes changes and damage on the specimens, making the histological assessment of resection margins, the gold standard for confirming radical tumor resection, sometimes difficult.

Objective To assess the different ways to manage patients depending on the status of the histopathological margin according to recent studies to detect the most commonly shared therapeutic strategy.

Data Synthesis We analyzed the literature available on the PubMed and Web of Science databases, including only articles published since 2005, using specific keywords to retrieve articles whose titles and abstracts were read and analyzed independently by two authors to detect relevant studies. Therefore, we focused on disease-free survival, overall survival, local control, laryngeal preservation, and disease-specific survival. Thus, 17 studies were included in the present review; they were grouped according to the status of the histological margin, and we analyzed the different management policies described in them. This analysis showed that there is not a shared strategy, though in most studies the authors performed a second-look surgery in the cases of positive margins and a close follow-up in cases of negative ones. The main disagreement is regarding the management of close or non-valuable resection margins, since some some authors performed a second-look surgery, and others, a close follow-up.

Conclusions Definitely, the most shared policy is the second-look surgery in case of positive surgical margins, and a close follow-up in case of close or non-valuable resection margins.

Key Points
Delivery Route and the Outcome of Newborn Hearing Screening of Full-Term Neonates Born in a Public Maternal-Infant Hospital in the South of Brazil
Authors: Vernier Luíza Silva , Schneider Karoline Lemos , Zanini Claudia , Paniz Tatiana , Levandowski Daniela Centenaro
Published: September 2020

Introduction The newborn hearing screening (NHS) is the most effective strategy for detecting newborns and infants suspected to have hearing loss.

Objective To verify possible associations between the route of delivery and the results of the NHS conducted at 3 independent times (24, 36, and 36 hours with a facilitator auricular maneuver [FAM]) in the lives of full-term newborns.

Methods A descriptive, observational, prospective study performed with a sample of 462 newborns, with a gestational age ≥ 37 weeks, without risk indicators of hearing loss. The NHS was conducted as a routine element of the facilities, two times: at 24 and 36 hours of life. In the presence of a “failure” in the last test, a new one was immediately performed, following the FAM. Statistic analyses were carried out on the program SPSS version 21.0 (IBM Inc., Armonk, NY, USA).

Results Of the 462 newborns assessed, 304 (65.80%) were born by vaginal delivery. There was a statistical significance of “pass” in the NHS for the 24-hour evaluation (p ≤ 0.001 for a vaginal delivery and p = 0.002 for a cesarean delivery), with the prevalence of the “pass” index being higher when the baby's lifespan was greater. A statistically significant difference was not observed when the NHS results were compared by taking into account the babies' routes of delivery and the different times of life.

Conclusion These findings show that full-term babies who were born by cesarean did not show more “failure” in the NHS results, contradicting the hypothesis of the study. Furthermore, to reduce the false-negative rates, regardless of the route of delivery, this assessment should be conducted after the first 24 hours of the newborns' life.
The Role of FNAC in the Diagnosis and Management of Warthin Tumour: Analysis of 74 Cases
Authors: Zahran Mohamed , Alsedra Sundus , Cope Daron , Youssef Ahmed
Published: September 2020

Introduction After pleomorphic adenoma, Warthin tumor gets its popularity as the second most common benign neoplasm of the parotid gland. Fine-needle aspiration cytology (FNAC) is the most cost-effective and minimally-invasive way to determine the histological character of a parotid gland tumor.

Objective To determine the accuracy of FNAC in the diagnosis of Warthin Tumour.

Methods A retrospective study conducted between 2014 and 2018. Out of 243 FNACs performed for parotid lesions, a histopathological correlation was established in 74 cases to reveal the accuracy of FNAC in the diagnosis of Warthin tumor.

Results A total of 243 FNACs of parotid lesions were performed, and a histopathological correlation was established in 74 (30.4%) cases. Later on, we confirmed that 16 (21.6%) out of these 74 patients had cases of Warthin tumor. In total, 15 (20.3%) out of those 74 cases were confirmed as Warthin tumors on the initial cytology, which revealed a true positive concordance between the cytology and the final histological diagnosis; 55/74 (74%) were true negative results; on the other hand, 1/74 (1.4%) was a false negative, and 3/74 (4.1%) were false positive results. The sensitivity of the FNAC in the diagnosis of Warthin tumor was of 93%, while the specificity was of 94.8%, and the accuracy, of 94.6%.

Conclusion In the present study, FNAC had a high diagnostic accuracy, reaching 94%.
Imaging Studies in Otosclerosis: An Up-to-date Comprehensive Review
Authors: Mangia Lucas Resende Lucinda , Coelho Luiz Otávio de Mattos , Carvalho Bettina , de Oliveira Adriana Kosma Pires , Hamerschmidt Rogerio
Published: September 2020

Introduction Otosclerosis is a primary osteodystrophy of the otic capsule, frequently responsible for acquired hearing loss in adults. Although the diagnostic value of imaging investigations in otosclerosis is debatable, they might still be employed with different goals within the context of the disease.

Objectives The present paper aims to review the most recent literature on the use of imaging studies in otosclerosis for the most varied purposes, from routine application and differential diagnosis to prognostic prediction and investigation of surgical failure.

Data Synthesis The diagnosis of otosclerosis is usually clinical, but computed tomography (CT) is paramount in particular cases for the differential diagnosis. The routine use, however, is not supported by strong evidence. Even so, there is growing evidence of the role of this method in surgical planning and prediction of postoperative prognosis. In specific scenarios, for example when superior semicircular canal dehiscence (SSCD) syndrome is suspected or in surgical failure, CT is crucial indeed. Magnetic resonance imaging (MRI), however, has limited – although important – indications in the management of individuals with otosclerosis, especially in the evaluation of postoperative complications and in the follow-up of medical treatment in active ostosclerosis.

Conclusion Imaging studies have a broad range of well-established indications in otosclerosis. Besides, although the routine use of CT remains controversial, the most recent papers have shed light into new potential benefits of imaging prior to surgery.
Mesenchymal Stem Cells Attenuate Lipopolysaccharide-Induced Inflammatory Response in Human Uterine Smooth Muscle Cells
Authors: Mani Arunmani , Hotra John W. , Blackwell Sean C. , Goetzl Laura , Refuerzo Jerrie S.
Published: September 2020

Objective The aim of this study was to determine if mesenchymal stem cells (MSCs) would suppress the inflammatory response in human uterine cells in an in vitro lipopolysaccharide (LPS)-based preterm birth (PTB) model.

Study Design Cocultures of human uterine smooth muscle cells (HUtSMCs) and MSCs were exposed to 5 μg/mL LPS for 4 hours and further challenged with 1 μg/mL LPS for a subsequent 24 hours. Key elements of the parturition cascade regulated by toll-like receptors (TLRs) through activation of mitogen-activated protein kinases (MAPKs) were quantified in culture supernatant as biomarkers of MSC modulation.

Results Coculture with MSCs significantly attenuated TLR-4, p-JNK, and p- extracellular signal-regulated kinase 1/2 (ERK1/2) protein levels compared with HUtSMCs monoculture (p = 0.05). In addition, coculture was associated with significant inhibition of proinflammatory cytokines interleukin (IL)-6 and IL-8 (p = 0.0001) and increased production of anti-inflammatory cytokines IL-10 and transforming growth factor (TGF)-β1 (p = 0.0001).

Conclusion MSCs appear to play a role in significantly attenuating LPS-mediated inflammation via alteration of down-stream MAPKs. MSCs may represent a novel, cell-based therapy in women with increased risk of inflammatory-mediated preterm birth.
Establishing Better Evidence on Remote Monitoring for Postpartum Hypertension: A Silver Lining of the Coronavirus Pandemic
Authors: Sawyer Michala R. , Jaffe Elana F. , Naqvi Mariam , Sarma Amy , Barth William H. , Goldfarb Ilona T.
Published: September 2020

The transformation of our health care system in response to coronavirus disease 2019 (COVID-19) provides a unique opportunity to examine the use of telehealth for postpartum care. The postpartum period can pose significant risks and challenges, particularly for women with hypertensive disorders of pregnancy. Remote blood pressure monitoring has proven feasible and acceptable among women and providers but has not been widely implemented or researched. Early studies have identified improved outcomes with use of telehealth, including increased compliance with care and decreased disparity in hypertension follow-up. Preliminary data make a compelling case for remote monitoring as a promising treatment strategy to manage postpartum hypertension. Remote monitoring technology should be incorporated as a standard component for the comprehensive management of postpartum hypertension during COVID-19. As a consequence of the pandemic, we now have an opportunity to research the impact of postpartum remote blood pressure monitoring on maternal outcome and disparities within these outcomes.
Evaluation of a Fixed-Angle Wedge Osteotomy Guide
Authors: Neal Katherine M. , Frederick Steven W. , Corse Matthew R. , Cross Alan R.
Published: September 2020

Objective The aim of this study was to evaluate a fixed-angle cutting guide designed to aid in the performance of coplanar wedge osteotomies using a proximal tibial cranial closing wedge ostectomy model.

Study Design A 30-degree cranial closing wedge ostectomy was created using canine tibia models with either a standard template (method T) or a wedge osteotomy guide (method G) by two surgeons. One surgeon was experienced with both procedures, and one surgeon had no previous experience with the wedge guide. The ostectomy wedges were evaluated for wedge angle, using a digital protractor, and coplanarity by using digital photographs and screen-measuring software.

Results The mean (standard deviation) wedge angles of the T and G groups were 28.16 (1.33) and 28.4 degrees (1.46) respectively. The mean (standard deviation) divergence angles of the T and G groups were 3.21 (1.86) and 2.22 degrees (1.69) respectively. The measured reference angles of the template and cut guides were 31.27 and 29.60 degrees respectively. Individual and cross-surgeon analysis of outcomes found no significant differences when comparing wedge angle or coplanarity with either method regardless of surgeon experience. However, mean wedge angle of group G was significantly closer to the measured reference angles than group T (p < 0.01).

Conclusion Use of a fixed-angle surgical wedge guide was successful in consistently producing accurate closing wedge ostectomies regardless of surgeon experience. These results show that use of the guide is a valid method for performing wedge ostectomies.
Response of an Obstetric Unit during the Coronavirus Disease of 2019 (COVID-19) Pandemic: Experiences from a Tertiary Care Center
Authors: Kumaraswami Sangeeta , Pradhan Tana S. , Vrabie-Wolf Sorana , Lodhi Sadaf , Rajendran Geetha P. , Tedjarati Sean S. , Grimes Cara L.
Published: September 2020

Objective To describe our experiences in preparing our obstetric unit in Westchester County, New York, during the COVID-19 (coronavirus disease of 2019) pandemic. We focus on describing our timeline, continuously evolving actions, observations, and challenges.

Methods With guidance from the New York State Department of Health (NYSDOH), our institutional epidemiologist, and key multidisciplinary faculty members, we evaluated emerging national data as well as expert opinions to identify issues and challenges to create action plans.

Results We created and modified policies for our patients presenting for obstetrical care on the labor and delivery unit to accommodate their unique needs during this pandemic.

Conclusion The COVID-19 pandemic has posed many unique challenges. Balancing communication, risks of infection to providers, patient autonomy and rights, and resources for testing and personal protective equipment were among the valuable lessons learnt. We have shared our experiences and described our observations and challenges in Westchester County, New York.
Associations among Discharge Opioid Prescribing and Inpatient Postpartum Opioid Usage after Delivery
Authors: Veade Ashley , McKinnish Tyler , Carter Ebony , Lewkowitz Adam
Published: September 2020

Objective The aim of the study is to identify an association between inpatient opioid consumption and prescription at discharge after vaginal delivery (VD) and cesarean delivery (CD).

Methods This retrospective cohort study included women with an active inpatient opioid order after VD or CD between July and October of 2018 at a single academic tertiary hospital. Women with opioid use disorder, 3rd or 4th degree lacerations, wound complications, and peripartum hysterectomy were excluded. Oxycodone 5-mg (mg) tablets consumed postpartum and prescribed at discharge and sociodemographics were recorded. Primary outcome was the number of oxycodone 5-mg tablets prescribed at discharge. Outcomes were analyzed using multivariable logistic regression between quartiles of inpatient opioid consumption.

Results A total of 437 patients were included: 169 patients underwent VD, and 268 underwent CD. For VD and CD, women in the highest quartile of inpatient opioid consumption were more likely Black compared with the lowest quartile (p = 0.006 and p = 0.004, respectively). No association existed between inpatient opioid use and number of tablets prescribed at discharge for VD or CD (odds ratio [OR] 0.22 [95% confidence interval or CI 0.02–2.17] and OR 1.04 [95% CI 0.85–1.32], respectively).

Conclusion The number of opioid tablets prescribed at discharge had no association with inpatient postpartum consumption after VD or CD.
Intracranial Intradural Vascular Injury during Endoscopic Endonasal Transsphenoidal Surgery: A Case Report and Literature Review
Authors: Babgi Mohammed , Alsaleh Saad , Babgi Yaser , Baeesa Saleh , Ajlan Abdulrazag
Published: September 2020

Background Transsphenoidal surgery (TSS) is a procedure for sellar or midline masses in the skull base. Among the reported complications are iatrogenic vascular injuries; that are rare, yet they carry devastating outcomes, with an incidence of injury between 0.34 and 2.6%. The cavernous internal carotid artery is the most commonly injured. However, intradural arterial injuries are much less reported with challenging management. We report a rare incident of intradural arterial injury during TSS, and we compared our management to the summarized few cases reported in the literature

Case Report We report a 43-year-old female who had a recurrent planum sphenoidal meningioma. She underwent trans-nasal transsphenoidal endoscopic resection that was complicated with intraoperative bleeding due to an injury to the anterior communicating artery that was challenging to control, resulted in a bilateral loss of flow in A1 segments of anterior cerebral artery and required endovascular management. The patient had a good recovery postoperatively without the typical picture of ACA syndrome.

Conclusion Intradural arterial injury is exceedingly rare in TSS, with no clear standard of care for the management. Collateral blood supply allows definitive management with minimal morbidity. Identifying the risk factors beforehand, as well as performing such cases in a well-resourced center, are crucial elements of safety.
Response of lipid productivity to photosynthesis of Chlorella vulgaris under various nutrient stress modes
Authors: Li Pengfei , Sun Xin , Sun Xiaoqin , Tang Jiagang , Turaib Ali , Wang Xu , Cheng Zhiwen , Deng Linyu , Zhang Yudong
Published: September 2020

Chlorella vulgaris is a valuable source of lipids that can be used for biodiesel. Chlorella can effectively absorb nitrogen (N) and phosphorus (P), which can change growth characteristics, intracellular components, and photosynthesis capacity. This research analyzes the photoautotrophic cultivation of Chlorella under various nutrient modes, aiming to identify the conditions with maximum lipid production and enhanced photosynthesis. Results show that nutrient stress affects the biomass, morphology, and lipid productivity significantly. The optimal lipid content (61.77 mg·L−1 for N, 3.56 mg·L−1 for P, and a combination of concentrations 123.53 mg·L−1 for N and 3.56 mg·L−1 for P), increases by >57%, >37%, and >18%, respectively. The maximum lipid production, achieving >124 mg L−1 and increasing by >40%, is usually accompanied by a high level of photosynthetic capacity. Lipid production and actual photochemical quantum yield decrease gradually with increasing nutrient concentrations, so that high environmental stress on algae leads to a significant decrease in the maximum quantum yield under excessive nutrient concentrations. Similarly, the electron transfer rate also shows a decreased level with increasing nutrient concentrations. The ΔFν/Fm can be used for estimating lipid accumulation, and was proposed to be 0.18–0.20. This study indicates that different responses of photosynthetic capacity have an effect on lipid accumulation under various nutrient modes and that the photosynthetic capacity can be used to forecast lipid accumulation.
Optical, thermal, and structural performance analyses of a parabolic-trough solar collector
Authors: Wang Chunwei , Hu Yanwei , He Yurong
Published: September 2020

Parabolic-trough solar collectors are widely used in solar thermal power-generation stations because the structure is simple and inexpensive. However, many factors affect their performance. Here, we derive an optical-thermal-structure numerical method. The heat flux is unevenly distributed along the circumferential direction of the absorber tube, resulting in uneven temperature distribution. An area of stress concentration is apparent at a rim angle of about 75°, and the maximum von Mises stress is approximately 100 MPa, near the fixed end of the tube. As the geometric concentration ratio increases, the position of maximum heat flux gradually moves to the bottom of the tube. An increase in this value increases the heat transfer fluid temperature, and the stress on the tube rises as the temperature distribution becomes more inhomogeneous. As the rim angle increases, the position of maximum heat flux gradually shifts to the sides of the tube. The stress on the tube then decreases because the temperature distribution becomes more uniform. The performance of a parabolic-trough solar collector can be improved by changing the geometric concentration ratio and rim angle, taking care to ensure no material failure. Optical, heat transfer, and thermal stress analyses of a parabolic-trough solar collector were systematically performed. This study provides guidance for practical engineering applications of parabolic-trough solar collectors.
Smart multi-level energy management algorithm for grid-connected hybrid renewable energy systems in a micro-grid context
Authors: Chakir Asmae , Tabaa Mohamed , Moutaouakkil Fouad , Medromi Hicham , Alami Karim
Published: September 2020

The intermittency of single renewable energy sources affects significantly their reliability, and hence, hybrid renewable energy systems (HRESs) are introduced. HRESs are notably used to meet the needs of residential loads. Nevertheless, power surplus and shortages still represent issues that must be handled by energy management systems. In this paper, a novel method for optimal energy management of a grid connected micro-grid composed of five smart Moroccan prosumers is presented. The proposed energy management strategy is organized using three levels, namely, HRES level, load-scheduling level, and communication-sharing level between HRESs. The first two levels of energy management are processed at the local level, i.e., inside each smart home. For the third level, our paper demonstrates the feasibility of interactions and communication between the five different houses interconnected using an optimized infrastructure topology as a smart neighborhood grid. Each of these houses is empowered by their own hybrid renewable energy system made of possible system hybridization based on PV (Photovoltaic), wind turbine, and battery storage system. This helps each house to manage its surplus and to deal with energy shortage through the proposed multi-level system's energy management algorithm. The application of information and communication technologies enables the set of smart homes connected in a micro-grid framework to contribute to the emergence of the concept of the internet of sustainable green things. Simulations conducted by the MATLAB platform validate the proposed methodology, which relies on micro-grid surplus injection and neighborhood storage during extreme surplus, else load dynamics thereafter micro-grid-injected energy recovering during hybrid energy deficit. The proposed system manages the energy produced by HRESs and reduces the energy demanded by the utility grid using the proposed topology that connects houses and ensures interactions between the micro-grid and the utility. The results show that the frequency of micro-grid deficiency was significantly reduced due to the established micro-grid with the five houses according to the proposed topology and the developed multi-level management system.