bluuebunny/crossref_metadata_2025 huggingface dataset:
Microembossed copper microchannel heat sink for high‐density cooling in electronics
Authors: Li Xuanyang , Chen Jing
Published: August 2019

A microembossed copper microchannel heat sink was designed and fabricated for high‐density cooling in electronics. The microchannel width and aspect ratio were investigated to find out the optimised channel size for microembossing. The fabrication method was based on bulk copper forming including tungsten die inductively coupled plasma etching, hot copper microembossing, inlet/outlet ports punching and sealing. The heat dissipation performances were tested by ceramic heater. The maximum temperature decreased to ∼37°C under different heat fluxes, with the maximum temperature decreased by 69.2% at 50 W/cm2 heat flux. The equivalent heat transfer coefficient reached the value of 6492 W/m2 K. High‐power chip was used as heat source too. The maximum heat flux reached 304.8 W/cm2 when the chip can still function properly at 90.5°C. High cooling performance with the micro‐heat sink proves that microembossing by tungsten die is an alternative process for microchannel heat sink fabrication with batch production and low cost. Taking advantages of simple fabrication process and reutilisation of tungsten die, the technology shows promising potentials in high‐density microcooling systems.
Impact of ICM disturbances on the mean pressure profile of galaxy clusters: A prospective study of the NIKA2 SZ large program with MUSIC synthetic clusters
Authors: Ruppin F. , Sembolini F. , De Petris M. , Adam R. , Cialone G. , Macías-Pérez J. F. , Mayet F. , Perotto L. , Yepes G.
Published: August 2019

Context. The mean pressure profile of the galaxy cluster population plays an essential role in cosmological analyses. An accurate characterization of the shape, intrinsic scatter, and redshift evolution of this profile is necessary to estimate some of the biases and systematic effects that currently prevent cosmological analyses based on thermal Sunyaev-Zel’dovich (tSZ) surveys from obtaining precise and unbiased cosmological constraints. This is one of the main goals of the ongoing NIKA2 SZ large program, which aims at mapping the tSZ signal of a representative cluster sample selected from thePlanckand ACT catalogs and spans a redshift range 0.5 <  z <  0.9.

Aims. To estimate the impact of intracluster medium (ICM) disturbances that can be detected by NIKA2 on the mean pressure profile of galaxy clusters, we realized a study based on a synthetic cluster sample that is similar to that of the NIKA2 SZ large program.

Methods. To reach this goal we employed the hydrodynamical N-body simulation Marenostrum MUltidark SImulations of galaxy Clusters (MUSIC). We simulated realistic NIKA2 andPlancktSZ observations, which were jointly analyzed to estimate the ICM pressure profile of each cluster. A comparison of the deprojected profiles with the true radial profiles directly extracted from the MUSIC simulation allowed us to validate the NIKA2 tSZ pipeline and to study the impact of ICM disturbances on the characterization of the ICM pressure distribution even at high redshift. After normalizing each profile by the integrated quantities estimated under the hydrostatic equilibrium hypothesis, we evaluated the mean pressure profile of the twin sample and show that it is compatible with that extracted directly from the MUSIC simulation in the scale range that can be recovered by NIKA2. We studied the impact of cluster dynamical state on both its shape and associated scatter.

Results. We observe that atR500the scatter of the distribution of normalized pressure profiles associated with the selected morphologically disturbed clusters is 65% larger than that associated with relaxed clusters. Furthermore, we show that using a basic modeling of the thermal pressure distribution in the deprojection procedure induces a significant increase of the scatter associated with the mean normalized pressure profile compared to the true distribution extracted directly from the simulation.

Conclusions. We conclude that the NIKA2 SZ large program will facilitate characterization of the potential redshift evolution of the mean pressure profile properties due to the performance of the NIKA2 camera, thereby allowing for a precise measurement of cluster morphology and ICM thermodynamic properties up toR500at high redshift.
Rotating baryonic dark halos
Authors: De Paolis F. , Gurzadyan A. V. , Nucita A. A. , Gurzadyan V. G. , Qadir A. , Kashin A. , Amekhyan A. , Sargsyan S. , Jetzer Ph. , Ingrosso G. , Tahir N.
Published: August 2019

Galactic halos are of great importance for our understanding of both the dark matter nature and primordial non-Gaussianity in the perturbation spectrum, a powerful discriminant of the physical mechanisms that generated the cosmological fluctuations observed today. In this paper we analyze Planck data towards the galaxy M 104 (Sombrero) and find an asymmetry in the microwave temperature which extends up to about 1° from the galactic center. This frequency-independent asymmetry is consistent with that induced by the Doppler effect due to the galactic rotation and we find a probability of less than about 0.2% that it is due to a random fluctuation of the microwave background. In addition, Planck data indicate the relatively complex dynamics of the M 104 galactic halo, and this appears to be in agreement with previous studies. In view of our previous analysis of the dark halos of nearby galaxies, this finding confirms the efficiency of the method used in revealing and mapping the dark halos around relatively nearby edge-on galaxies.
Efficiency analysis of implementing hybrid printing technologies
Authors: Berculescu Liviu , Bălan Emilia , Mohora Cristina , Tudor Mariana
Published: August 2019

The paper analyses 4 printing technological flow cases, considering the author’s experience (over 15 years) in the printing industry to improve the production efficiency. The productivity, the quality and the delivery time are the main areas of interest for people working in the printing & finishing industry, where the print demand structure evolved and the costs of replacing machines are very high. The implementation of the organisational and reconfiguration of machines changes contribute to the development of new efficient working structures within the printing process, therefore increasing the efficiency of it, as one can notice from the diagrams presented in the paper. The time and the costs presented have been obtained through a couple of trials of modifying the work parameters, the colour and the materials according to the colour management guidelines in use. Ultimately the optimal technological structure has been chosen for quality improvement, cost and delivery time reduction.
Automation possibilities in a low rotation warehouse of a Belgian manufacturing plant. A case study
Authors: Mocan Anca , Draghici Anca
Published: August 2019

Lack of appropriate warehouse ergonomics is one of the leading causes of worker injuries in industry environments. As management teams are trying to reduce the cost of doing business, they look to worker’s health statistics and realize they must improve their way of operating. The paper presents a warehouse analysis done at the request of the management team of a Belgian manufacturing plant. The factory’s warehouse was audited with focus on Kanban bin weight, storage rack height and rack width to assess the ergonomic strain it causes on workers. The paper then presents possible automation options in order to find the best fit to reduce ergonomic impact, while also optimizing the total investment cost.
A Study of Milk Particles Size Variation with pH Change using Dynamic Light Scattering
Authors: Chicea Dan , Chicea Liana Maria
Published: August 2019

A very simple experimental setup for a Dynamic Light Scattering measurement was used to measure the average size of the milk proteins in aqueous suspensions at 20 °C. The PH of the suspensions was adjusted using Calcium lactate, in its most common form of pentahydrate C6H10CaO6•5H2O. The mean size variation of the suspended particles in time has been monitored and reveals a fast increase over a time interval of less than ten of seconds.
Simulation of the Single Point Incremental Forming of Polyamide and Polyethylene Sheets
Authors: Roşca Nicolae Alexandru , Oleksik Mihaela
Published: August 2019

The present paper aims the theoretical study, using the finite element method, on the single point incremental forming process of two polymeric materials: polyamide 6.6 and high-density polyethylene. The experimental researches used for the determination of the true stress - true strain curves for two materials are presented, which are necessary for their introduction into the simulation. The explicit analysis is carried out with the Ls-Dyna program and the results of the analysis were focused on the major strain, minor strain, thickness reduction, forces on the process and total energy consumed in the process.
Researches regarding scale reduced models for the optimisation of the aerodynamic coefficient
Authors: Stanciu Alexandru Lucian , Pascu Nicoleta , Dogariu Constantin , Mohora Cristina
Published: August 2019

Within the lifecycle of the product, the reduced models are very important for the experimental validation of the prototype. The modelling, simulation and optimization stage precedes the prototype realization, being part of the computer aided design (CAD), computer aided engineering (CAE). The physical model is a physical layout or test setup that reproduces, on a small scale, the features of the original system, in our case the vehicle body layout. The paper presents an automobile reduced model, with the aim to study the aerodynamic theory. The paper presents the algorithms of conceptual design of the scale reduced model, namely: 3D modelling, small scale modelling technology and geometric shape optimization solutions using different CAD-CAE programs.
Research on the quality assurance of fermented dairy products with addition of bioactive compounds from medicinal plants
Authors: Tiţa Ovidiu , Constantinescu Adelina Maria , Tiţa Mihaela Adriana
Published: August 2019

Fermented dairy products are highly appreciated due to the benefits that bring to consumers’ health and because they can be eaten at an early age. Extracts of medicinal plants have been used since antiquity, including in the treatment of digestive diseases. These medicinal plants bring many benefits to consumers and they help to treat numerous digestive disorders, diseases caused by stress or irritation of the skin. The objective of this research is to identify hazards, to assess risks and to establish critical control points from the technological flow of obtaining fermented dairy products with the addition of bioactive compounds from medicinal plants. The methods used to conduct research are different qualitative analysis tools because bioactive compounds from medicinal plants require more special processing conditions.
Outsourcing Towards Greater Agility Through Investigating Decoupling Points in Leagile Supply Chains
Authors: Faur Monica , Bungau Constantin
Published: August 2019

In today’s competitive business environment, with a continuously increasing diversity in customer demand, a high level of supply chain responsiveness is an imperative requisite for companies’ survival. As a consequence, enhanced agility is requested for the supply chains. The purpose of this paper is to investigate the determinants that influence the position of the ‘decoupling points’ along the value chain, as according to the reviewed literature these represent the separation point between leanness and agility in a hybrid supply chain. It has been found that by applying different technical solutions along the chain, including breaking down the complete production process in modular sequences and outsourcing specific ones, considering reshaping the supply chain, the decoupling points’ location can be moved, allowing greater agility. The chosen methodology is a case study of a FMCG company, aiming to illustrate how increased agility is achieved by outsourcing labour-intensive and time consuming activities, while shortening the downstream to customer. The selected firm is since several years under Lean and Agile strategies implementation. The study shows that understanding both, material and information decoupling points, certain lean processes can be moved upstream, leveraging more agile processes close to the end customer. This way, supply chains can be redesigned towards increasing market responsiveness.
Research on the designing of pneumatic positioning units controlled with valves commanded in modulated pulses
Authors: Avram Mihai , Constantin Victor , Niță Emil-Ionuț
Published: August 2019

This article presents the hardware structure for a new type of closed loop positioning system using pneumatic energy. In brief, when the mobile subassembly of the system is about to reach a targeted position its speed is controlled by the small-sized pneumatic electro valves, which are commanded in modulated pulses. Here, we developed an electronic control system of which memory has a specially designed algorithm. In addition, the pneumatic engine has a specific construction that integrates a transducer of position as well as a braking system. The proposed mechatronic system is described by good positioning accuracy and low cost.
Evaluations of the voice to text transfer in different conditions
Authors: Janíček Matej , Velíšek Karol , Holubek Radovan , Ružarovský Roman
Published: August 2019

The purpose of the research was evaluations of voice to text transfer in different conditons for the use in the verbal control of industrial robots. The research aims to find the best conditions to command an industrial robot using the human voice. A comprehensive study of existing problems and suggestions for simulation problems has been performed. Unlike some other works, it focused on the simply external problems to affect the voice to text transfer. The main problems of voice to text transfer (speech speed, speaker distance, ambient noise) has been established. The simulation using a personal computer equipped with a sound board and a headset microphone has been performed in all combinations of conditions. On the basis of the analyzes was establish the result of this research, the most suitable conditions and the worst conditions for voice to text transfer.
Technical Solution of the Drive System for Mixing Dough Machine
Authors: Miltenović Aleksandar , Banić Milan , Velimirović Nikola
Published: August 2019

In the conditions of the global economy, food industry products have a good share in international trade. It is primarily ready-made food products that are ready for use. The basic problem that needs to be solved is the safety and quality of food products. Machine “Planetary mixer” is used for mixing and preparing dough. From the aspect of optimal fulfilment of the working function of the preparing dough “Planetary mixer” has to fulfil the following conditions: - the complete space in which the dough is located must be treated equally with the mixer; - noise and vibration reduction should be ensured and appropriate precision positioning of the machinery’s executive bodies; - a compact construction of the drive system is required with the optimum utilization of the available resources. In the paper is presented technical design solution of the drive system for machine based on the demands of regional medium size enterprise and therefore it is limited to the requirements of the investor. The final solution was achieved by using the modern methods of product development.
Research regarding the upgrading of the attachments for balance ropes of mine hoists
Authors: Dumitrescu Iosif , Grecea Danut , Vitan Cosmin , Vitan Dorel
Published: August 2019

The research approaches the possibilities of modernizing the cable fastening devices for balancing mining hoisting engines with a view to increase functioning safety and to decrease the costs of manufacturing. Modern means of investigation are employed so that the proposed solutions are well-grounded and display a certain degree of generality in order that the technology might also be applied to other technical circumstances in the industry of resource extraction and capitalization.
MEVA - a new method of occupational health and safety risk assessment
Authors: Darabont Doru-Costin , Smîdu Eduard , Trifu Alina , Ciocîrlea Vicențiu , Ivan Iulian , Bejinariu Costică , Baciu Constantin , Bernevig-Sava Mihai-Adrian
Published: August 2019

The paper describes a new method of occupational health and safety risk assessment. This method, called MEVA, unlike the old ones, focuses more on reduce or eliminate subjective issues in determining the probability of manifestation of risk factors and is based on a deductive reasoning, with the help of which is studied the chain between two or more events. The novelty of the method consists in combining risk assessment techniques with evaluation of compliance with legal and other requirements, aiming to provide a more objective results of the risk assessment. In the MEVA method, the risk matrix is defined by 5 classes of severity and 5 probability classes, resulting in 5 levels of risk. After quantifying the risk factors, prevention measures are proposed for all the identified risk factors and each partial risk level is recalculated as a result of the proposed measures. The five levels of risk were grouped into three categories: acceptable, tolerable and unacceptable. The MEVA method is a simple method and it can be used for assessing various workplaces, with different characteristics of complexity, activity domain or occupational health and safety recordings.
Implementation of an occupational stress Control Model
Authors: Dascalu Loredana Cristina , Iacobescu Gabriel , Dimitrescu Andrei , Semenescu Augustin , Petrescu Valentin
Published: August 2019

Occupational stress is an enemy of society, a problem that requires a deep research to control stress more effectively. The case study presented in this article consists of a model control regarding occupational stress. The experimental part of this study involved interviews with 15 employees, 9 females and 6 males aged between 25-55 years. Participants described stressful situations at work. Time allocated for each subject was 45 minutes per interviews. The model was implemented based on the job content stressors, effects of stress (physiological, psychological, behavioural) and interviews results. Future directions in stress research is to identify the way to have control in the workplace because, in my opinion, that it is the key factor for good results and health.
Civilian – military interferences in the management of research for the security and defense field
Authors: Badea Dorel , Mănescu Gabriel , Iancu Dumitru , Bucoveţchi Olga , Dinicu Anca
Published: August 2019

Changes in the security spectrum, in terms of reconfiguring its military content, subsequently involves another approach to security and defense research. Especially the economic aspects have a quantitative and qualitative impact on the management of the research specific to this field, which has long been taken for granted, causing changes in both the interests and the power of influence held by different categories of stakeholders. This article explores the main directions of change within the aforementioned framework, highlighting the major modalities of involving the civilian segment of capabilities and specialized assets, on a track considered for a long time and to a much greater extent compared to the present imperatives, as an area dedicated exclusively to the military. The thematic target approached by the team of authors includes both national and international plans, individualized or clustered, at the current level but also as trends, the main aim of the scientific approach is that of highlighting good practices in the field of research and development of dual-use products. The conclusion is that the possibilities of the civilian-military academic cooperation can be better grounded in order to achieve better results in terms of the operationalization of the security interest in a comprehensive manner, materialized mainly through research projects.
Designing rigorous and relevant learning experiences for future teachers
Authors: Creţu Daniela-Maria
Published: August 2019

Teaching and learning at the university should help students develop complex thinking about the issues they are dealing with and practice skills needed to solve real-world problems. The Rigor/Relevance Framework, developed by the staff of the International Center for Leadership in Education (ICLE), is a useful tool for designing learning experiences that increase the rigor and the relevance of the curriculum. This model integrates Bloom’s taxonomy with its six levels (remembering, comprehension, application, analysis, synthesis, and evaluation) with the Application Model, which has five levels (knowledge in one discipline, apply in discipline, apply across disciplines, apply to real-world predictable situations and apply to real-world unpredictable situations). The combination of these two dimensions results in four quadrants: Acquisition, Application, Assimilation, Adaptation, in which learning experiences can be designed to raise the rigor and relevance of instruction. The aim of this study is to exemplify the use of the Rigor/Relevance Framework in designing the learning experiences offered during two courses for future teachers for primary and preschool education. The implications of selecting appropriate instructional strategies and student assessment methods are discussed.
An ADOxx Based Environment for Problem Based Learning in Manufacturing Systems Design
Authors: Mironescu Ion Dan
Published: August 2019

The Problem Based Learning (PBL) as student centred approach and learning-by-doing method is suited for the modern higher education. However, the first contact with the method can be overwhelming for the students, in the absence of prior domain knowledge. The preparation of the learning material can be time and resource consuming for the teacher. The goal of the research was the implementation of an environment that should enhance the learning experience for the student and reduce the implementation burden for the teacher. The environment is based on the ADOxx platform and allows the collaboration of the learner teams and the teacher-learner interaction on three levels. The Metamodeling level supports the development of the domain-specific language used in the modelling of the manufacturing system; this activity stimulates and directs the gathering and consolidation of domain-specific knowledge. The modelling level allows the development of alternative design solution using models of the factory components. The Simulation level allows the analysis of these variants. The environment supports the teacher in developing instructional scaffolding and uses cases to ease the learners the first time contact with PBL. The functionality of the environment is presented using the case of designing a flexible food production line.
A new genus and species of pinworm (Nematoda, Oxyuridae) from the gray mouse opossum, Tlacuatzin canescens
Authors: Jiménez F. Agustín , Caspeta-Mandujano Juan Manuel , Albino-Miranda Sergio
Published: August 2019

Tlacuatzoxyuris simpsoni n. gen. n. sp. is described from the cecum of the gray opossum, Tlacuatzin canescens, a species endemic to the deciduous dry forest of Mexico. The digestive tracts of four specimens were examined for parasites; three of these were archived in the American Museum of Natural History and one was a live capture. Relative to the other four monotypic genera of pinworms known to infect opossums, the new genus is diagnosed on the basis of a round cephalic plate with a semicircular stoma surrounded by a rim. In addition, males feature a prominent cephalic vesicle not fully developed in females, accounting for sexual dimorphism. The new species includes small worms that feature a conspicuous, not reticulated cephalic vesicle and semicircular stoma and lateral alae with two crests. In addition, the postcloacal cuticle of males features a small area with ornamentation between cloaca and submedial papillae. Finally, both spicule and gubernaculum are relatively short. Although the eggs of Tlacuatzoxyuris n. gen. are unknown, the conspicuous differences in traits used in the diagnosis of genera prompted us to propose a new genus for the new species. This is the first species of Oxyuridae reported in mouse opossums outside South America, and the fifth species of the family occurring in didelphimorph marsupials. This is an example of the usefulness of documenting the diversity of parasites associated with this unique clade of mammals through the examination of preserved tissues.
Kontrastmittelsonografie bei einem seltenen bilateralen
renalen Karzinom mit sekundärer Entzündung und Nekrose bei einer
Katze
Authors: Fromme Vivian , Köhler Claudia , Langguth Johann , Morales Isabel Cabrera , Alef Michaele , Kiefer Ingmar
Published: August 2019

Ein 17 Jahre alter, kastrierter Europäisch-Kurzhaar-Kater wurde aufgrund von
Inappetenz vorgestellt. Die klinische Untersuchung war ohne besonderen Befund.
Bei der sonografischen Untersuchung des Abdomens konnten an beiden Nieren
überwiegend reflexarme Umfangsvermehrungen im Rinden- und Kapselbereich
dargestellt werden. Die Ausprägung der Nierenveränderungen ließ sich durch
Kontrastmittelsonografie (contrast enhanced ultrasound, CEUS) und Kontrast-CT
eindrücklich darstellen. Von den Umfangsvermehrungen wurden in Narkose unter
Ultraschallkontrolle Feinnadelaspirate gewonnen, wobei teilweise eine in der
Kleintiermedizin unübliche Aspiration von dorsal erfolgte. Die entnommenen
Proben waren diagnostisch; die zytologische Untersuchung ergab beidseits den
deutlichen Verdacht auf ein renales Karzinom mit sekundärer Entzündung und
Nekrose. Unter symptomatischer Therapie besserte sich der Zustand der Katze
zunächst, doch wurde das Tier 2 Wochen später euthanasiert.
Blepharitis häufiger bei brachyzephalen Rassen und oft in
Kombination mit Hauterkrankungen
Authors: Schürg Andrea
Published: August 2019

Hunde mit Hautläsionen leiden häufig auch unter einer Blepharitis. Es ist
jedoch nicht leicht, sicher zwischen einer Blepharitis und einer
periokulären Dermatitis (POD) zu unterscheiden. Ziel der retrospektiven
Studie war, eine eindeutige Definition für eine ophthalmologische bzw. eine
dermatologische Erkrankung zu finden. Ferner sollte evaluiert werden, wie
sich eine Blepharitis auf die Tränenproduktion auswirkt.
Bilateraler Reflux – pro intravesikale Techniken
Authors: Kranz Jennifer , Steffens Joachim
Published: August 2019

Alle Antirefluxplastiken zeichnen sich durch eine hohe Erfolgsrate von über 90 % aus. Gemeinsames Ziel aller Verfahren ist die Bildung eines submukösen Tunnels, der viermal länger ist als der Ureterdurchmesser. Weltweit haben sich bei einem nicht dilatierten Harnleiter die extravesikale Antirefluxplastik nach Lich-Gregoir und beim dilatierten Ureter die Psoas Hitch-Ureterozystoneostomie bewährt. Zu den intravesikalen Operationsverfahren zählen die Technik nach Politano-Leadbetter und die gekreuzt-trigonale Reimplantation nach Cohen. Diese offen oder laparoskopisch/robotisch durchgeführten Standardverfahren weisen gegenüber einer endoskopischen Unterspritzung des refluxiven Harnleiterostiums höhere Erfolgsraten auf.

Indikation zu einer operativen Refluxkorrektur sind der höhergradige Refluxgrad IV und V, zusätzliche Begleitanomalien (Hutch-Divertikel, Ureter duplex, ektope Harnleitermündung) und eine erfolglose endoskopische Ostiumunterspritzung 1. Zudem ist eine ausreichende Nierenfunktion von ≥ 15 % der refluxiven Niere wichtig. Bei eingeschränkter Partialfunktion kann kein Nierenfunktionsgewinn erwartet werden. Im postoperativen Verlauf ergibt sich bei einer hochgradig eingeschränkten Nierenfunktion meist ein weiterer Funktionsverlust.
Analysis of Panax ginseng miRNAs and Their Target Prediction Based on High-Throughput Sequencing
Authors: Wang Yingfang , Peng Mengyuan , Chen Yanlin , Wang Wenjuan , He Zhihua , Yang Zemin , Lin Zhiyun , Gong Mengjuan , Yin Yongqin , Zeng Yu
Published: August 2019

Panax ginseng has been widely and effectively used as medicine for thousands of years. However, only limited studies have been conducted to date on ginseng miRNAs. In the present study, we collected 3 ginseng samples from the Changbai Mountain in China. Small RNA libraries were constructed and sequenced on the Illumina HiSeq platform. Sequencing analyses identified 3798 miRNAs, including 298 known miRNAs and 3500 potentially novel miRNAs. The miR166, miR159, and miR396 families were among the most highly expressed miRNAs in all libraries. The results of miRNA expression analyses were validated by qRT-PCR. Target gene prediction through computational and pathway annotation analyses revealed that the primary pathways were related to plant development, including metabolic processes and single-organism processes. It has been reported that plant miRNAs might be one of the hidden bioactive ingredients in medicinal plants. Based on the combined use of RNAhybrid, Miranda, and TargetScan software, a total of 50,992 potential human genes were predicted as the putative targets of 2868 miRNAs. Interestingly, the enriched KEGG pathways were associated with some human diseases, especially cancer, immune system diseases, and neurological disorders, and this could support the clinical use of ginseng. However, the human targets of ginseng miRNAs should be confirmed by further experimental validation. Our results provided valuable insight into ginseng miRNAs and the putative roles of these miRNAs.
Efficient Synthesis of Diverse 5-Thio- or 5-Selenotriazoles: One-Pot Multicomponent Reaction from Elemental Sulfur or Selenium
Authors: Zhang Lin-Lin , Li Ya-Ting , Gao Ting , Guo Sha-Sha , Yang Bei , Meng Zi-Hui , Dai Qi-Pu , Xu Zhi-Bin , Wu Qin-Pei
Published: August 2019

A sequential multistep reaction toward 5-thio- or 5-selenotriazoles has been established by generation of both copper(I) triazolides and sulfenylating or selenylating agents in situ, starting from elemental sulfur or selenium. This reaction features mild conditions, readily available and broad-scope substrates, good functional group compatibility, high efficiency and regioselectivity, easy operation, and ligand-free CuI.
A Clean Cut: Minimally Invasive Mitral Valve Replacement after Heart Transplantation
Authors: Kremer Jamila , Al-Maisary Sameer Saeed Ahmed , Szabó Gábor
Published: August 2019

A 50-year-old female presented with progressive heart failure due to obstruction of the mitral valve after heart transplantation in 2008. Through the occlusion catheter (IntraClude Intra-Aortic Occlusion Device), aortic cross-clamping, antegrade cardioplegia, and aortic root venting were performed.

Our case reports the first published study on minimally invasive mitral valve replacement for valve stenosis through intraluminal aortic clamping. The hazard of traumatic injuries can be reduced by avoiding resternotomy and circumventing adhesions between the aorta and the pulmonary artery after heart transplantation. Minimally invasive valve surgery is a safe and effective method with regard to short- and long-term results, especially in redo operations.
Laparoscopic Distal Pancreatectomy of a Solid Pseudopapillary Tumor (SPT) Achieves Long-Term Oncologic Safety and Multiorgan Preservation
Authors: ElHaddad Ahmed , Gasparella Paolo , Castellani Christoph , Singer Georg , Sorantin Erich , Zach Klara , Till Holger
Published: August 2019

The oncological safety of a laparoscopic approach for solid pseudopapillary tumors (SPTs) of the pancreas remains a matter of debate. We present the long-term follow-up of an adolescent girl with an SPT in the pancreatic tail. A multimodality workup including magnetic resonance imaging (MRI) revealed a complex, spherical mass of 4.4 cm × 3.6 cm × 4 cm most likely located in the pancreatic tail. All routine laboratory investigations and tumor markers were within normal limits (alpha fetoprotein [AFP], cancer antigen 125 [CA125], CA 19–9, carcinoembryonic antigen [CEA], adrenocorticotropic hormone [ACTH]). Diagnostic laparoscopy was performed to verify the origin of the tumor in the pancreatic tail. In a three-port technique the tumor was mobilized of the splenic vessels until a distal pancreatectomy could be completed. Histopathological examination confirmed the complete resection of a low-grade malignant SPT. The postoperative course was unremarkable. Regular pediatric oncological follow-up examinations for 3 years, including MRI every 6 months, ruled out recurrence and confirmed preservation of splenic and pancreatic functions. While data about the technical feasibility of a laparoscopic approach to pancreatic SPT are already available, this pediatric case report adds a long-term oncological and functional success to the available literature.
Magnetocapacitance effect and magnetostriction by the field-induced spin-crossover in [MnIII(taa)]
Authors: Otsuki Y. , Kimura S. , Awaji S. , Nakano M.
Published: August 2019

We report the magnetocapacitance effect and the magnetostriction in the spin-crossover (SCO) complex [MnIII(taa)] (H3taa = tris(1-(2-azolyl)-2-azabuten-4-yl)amine). It is shown that huge enhancements of dielectric constant and lattice volume are caused by the field-induced SCO transition from the low-spin to the high-spin states in [MnIII(taa)]. In addition, the temperature-field phase diagram of the field-induced SCO in thermal equilibrium state is clarified up to 28 T. Our analysis suggests that a large magnetocaloric effect can also be caused by the field-induced SCO. These results indicate the possibility of multiple control of various material properties by the field-induced SCO.
Decreasing CsPbI3 quantum size decreases charge separation and recombination
Authors: Liebendorfer Adam
Published: August 2019

New findings demonstrate how changing the size of quantum dots influences power conversion efficiency in a number of applications.
Heat tunes polarization in new dielectric metasurface design
Authors: Patrick Chris
Published: August 2019

A new germanium-based dielectric metasurface thermally controls light polarization, opening opportunities in compact tunable polarization synthesizers for various applications.
Spatial ecology of territorial populations
Authors: Weiner Benjamin G. , Posfai Anna , Wingreen Ned S.
Published: August 2019

Many ecosystems, from vegetation to biofilms, are composed of territorial populations that compete for both nutrients and physical space. What are the implications of such spatial organization for biodiversity? To address this question, we developed and analyzed a model of territorial resource competition. In the model, all species obey trade-offs inspired by biophysical constraints on metabolism; the species occupy nonoverlapping territories, while nutrients diffuse in space. We find that the nutrient diffusion time is an important control parameter for both biodiversity and the timescale of population dynamics. Interestingly, fast nutrient diffusion allows the populations of some species to fluctuate to zero, leading to extinctions. Moreover, territorial competition spontaneously gives rise to both multistability and the Allee effect (in which a minimum population is required for survival), so that small perturbations can have major ecological effects. While the assumption of trade-offs allows for the coexistence of more species than the number of nutrients—thus violating the principle of competitive exclusion—overall biodiversity is curbed by the domination of “oligotroph” species. Importantly, in contrast to well-mixed models, spatial structure renders diversity robust to inequalities in metabolic trade-offs. Our results suggest that territorial ecosystems can display high biodiversity and rich dynamics simply due to competition for resources in a spatial community.
A semiclassical theory of phase-space dynamics of interacting bosons
Authors: Mathew R , Tiesinga E
Published: August 2019

We study the phase-space representation of dynamics of bosons in the semiclassical regime where the occupation number of the modes is large. To this end, we employ the van Vleck-Gutzwiller propagator to obtain an approximation for the Green’s function of the Wigner distribution. The semiclassical analysis incorporates interference of classical paths and reduces to the truncated Wigner approximation (TWA) when the interference is ignored. Furthermore, we identify the Ehrenfest time after which the TWA fails. As a case study, we consider a single-mode quantum nonlinear oscillator, which displays collapse and revival of observables. We analytically show that the interference of classical paths leads to revivals, an effect that is not reproduced by the TWA or a perturbative analysis.
Collective oscillation modes of a superfluid Bose–Fermi mixture
Authors: Wen Wen , Wang Ying , Wang Jianyong
Published: August 2019

In this work, we present a theoretical study for the collective oscillation modes, i.e. quadrupole, radial and axial mode, of a mixture of Bose and Fermi superfluids in the crossover from a Bardeen-Cooper-Schrieffer (BCS) superfluid to a molecular Bose–Einstein condensate (BEC) in harmonic trapping potentials with cylindrical symmetry of experimental interest. To this end, we start from the coupled superfluid hydrodynamic equations for the dynamics of Bose–Fermi superfluid mixtures and use the scaling theory that has been developed for a coupled system. The collective oscillation modes of Bose–Fermi superfluid mixtures are found to crucially depend on the overlap integrals of the spatial derivations of density profiles of the Bose and Fermi superfluids at equilibrium. We not only present the explicit expressions for the overlap density integrals, as well as the frequencies of the collective modes provided that the effective Bose–Fermi coupling is weak, but also test the valid regimes of the analytical approximations by numerical calculations in realistic experimental conditions. In the presence of a repulsive Bose–Fermi interaction, we find that the frequencies of the three collective modes of the Bose and Fermi superfluids are all upshifted, and the change speeds of the frequency shifts in the BCS–BEC crossover can characterize the different groundstate phases of the Bose–Fermi superfluid mixtures for different trap geometries.
Effect of microstructures and textures on the anisotropy of mechanical properties of AZ31 magnesium alloy sheets subjected to high strain rate rolling
Authors: Liu Xiao , Wang Yangyang , Zhu Biwu , Xie Chao , Sun Youping , Yang Hui
Published: August 2019

The AZ31 magnesium alloy sheets with different microstructures and textures were produced by high strain rate rolling (HSRR) at various temperatures and strain rates. Tensile tests were carried out on AZ31 magnesium alloy sheets along rolling direction (RD), transverse direction (TD) and 45° along the rolling direction (45° RD) at room temperature. The microstructures and textures were determined. The Schmid factors (SFs) contour lines were also calculated. The tilt angle of the c-axis towards the RD affects the anisotropy of tensile strength. For the AZ31 magnesium alloy sheets subjected to relatively low strain rate rolling, the anisotropy of yield strength is comparatively obvious, due to the elongated grains. When the loading direction is close to basal plane, prismatic slip is not favored during tension deformation at room temperature. The anisotropy of yield strength mainly depends on the critical resolved shear stress/Schmid factor (CRSS/m) ratios of second-order (2nd-order) pyramidal slip.
Asparagine-linked glycosylation is not directly coupled to protein translocation across the endoplasmic reticulum inSaccharomyces cerevisiae
Authors: Shrimal Shiteshu , Cherepanova Natalia A. , Mandon Elisabet C. , Venev Sergey V. , Gilmore Reid
Published: August 2019

Mammalian cells express two oligosaccharyltransferase complexes, STT3A and STT3B, that have distinct roles in N-linked glycosylation. The STT3A complex interacts directly with the protein translocation channel to mediate glycosylation of proteins using an N-terminal–to–C-terminal scanning mechanism. N-linked glycosylation of proteins in budding yeast has been assumed to be a cotranslational reaction. We have compared glycosylation of several glycoproteins in yeast and mammalian cells. Prosaposin, a cysteine-rich protein that contains STT3A-dependent glycosylation sites, is poorly glycosylated in yeast cells and STT3A-deficient human cells. In contrast, a protein with extreme C-terminal glycosylation sites was efficiently glycosylated in yeast by a posttranslocational mechanism. Posttranslocational glycosylation was also observed for carboxypeptidase Y–derived reporter proteins that contain closely spaced acceptor sites. A comparison of two recent protein structures indicates that the yeast OST is unable to interact with the yeast heptameric Sec complex via an evolutionarily conserved interface due to occupation of the OST binding site by the Sec63 protein. The efficiency of glycosylation in yeast is not enhanced for proteins that are translocated by the Sec61 or Ssh1 translocation channels instead of the Sec complex. We conclude that N-linked glycosylation and protein translocation are not directly coupled in yeast cells.
Accurate estimation of microbial sequence diversity with Distanced
Authors: Hackmann Timothy J
Published: August 2019

Motivation

Microbes are the most diverse organisms on the planet. Deep sequencing of ribosomal DNA (rDNA) suggests thousands of different microbes may be present in a single sample. However, errors in sequencing have made any estimate of within-sample (alpha) diversity uncertain.

Results

We developed a tool to estimate alpha diversity of rDNA sequences from microbes (and other sequences). Our tool, Distanced, calculates how different (distant) sequences would be without sequencing errors. It does this using a Bayesian approach. Using this approach, Distanced accurately estimated alpha diversity of rDNA sequences from bacteria and fungi. It had lower root mean square prediction error (RMSPE) than when using no tool (leaving sequencing errors uncorrected). It was also accurate with non-microbial sequences (antibody mRNA). State-of-the-art tools (DADA2 and Deblur) were far less accurate. They often had higher RMSPE than when using no tool. Distanced thus represents an improvement over existing tools. Distanced will be useful to several disciplines, given microbial diversity affects everything from human health to ecosystem function.

Availability and implementation

Distanced is freely available at https://github.com/thackmann/Distanced.

Supplementary information

Supplementary data are available at Bioinformatics online.
Physiological consequences of rising water salinity for a declining freshwater turtle
Authors: Agha Mickey , Yanagitsuru Yuzo R , Fangue Nann A , Nowakowski A Justin , Kojima Laura V , Cech Joseph J , Riley Melissa K , Freeman Janna , Cocherell Dennis E , Todd Brian D
Published: August 2019

Sea-level rise, drought and water diversion can all lead to rapid salinization of freshwater habitats, especially in coastal areas. Increased water salinities can in turn alter the geographic distribution and ecology of freshwater species including turtles. The physiological consequences of salinization for freshwater turtles, however, are poorly known. Here, we compared the osmoregulatory response of two geographically separate populations of the freshwater Western Pond Turtle (Actinemys marmorata)—a species declining across its range in western North America—to three constant salinities: 0.4 ppt, 10 ppt and 15 ppt over 2 weeks. We found that turtles from a coastal estuarine marsh population regulated their plasma osmolality at lower levels than their conspecifics from an inland freshwater creek population 45 km away. Plasma osmolalities were consistently lower in estuarine marsh turtles than the freshwater creek turtles over the entire 2-week exposure to 10 ppt and 15 ppt water. Furthermore, estuarine marsh turtles maintained plasma osmolalities within 1 SD of their mean field osmolalities over the 2-week exposure, whereas freshwater creek turtles exceeded their field values within the first few days after exposure to elevated salinities. However, individuals from both populations exhibited body mass loss in 15 ppt water, with significantly greater loss in estuarine turtles. We speculate that the greater ability to osmoregulate by the estuarine marsh turtles may be explained by their reduced feeding and drinking in elevated salinities that was not exhibited by the freshwater creek population. However, due to mass loss in both populations, physiological and behavioural responses exhibited by estuarine marsh turtles may only be effective adaptations for short-term exposures to elevated salinities, such as those from tides and when traversing saline habitats, and are unlikely to be effective for long-term exposure to elevated salinity as is expected under sea-level rise.
A new unbiased and highly automated approach to find new prognostic markers in preclinical research
Authors: Neidnicht Martin , Mittermüller Daniela , Effenberger-Neidnicht Katharina
Published: August 2019

Data acquisition in (pre)clinical studies is often based on a hypothesis. Numerical algorithms, however, may help to find biomarkers from existing data without formulating any hypothesis. By simply assessing whether a statistical relationship exists between two parameters from a (unlimited) database, every (in)conceivable combination of data becomes a hypothesis. The aim was to create an unbiased and highly automated approach for secondary analysis of (pre)clinical research, including the possibility of a non-linear functional relationship. In our example, an almost homogeneous database was formed by overall 45 parameters (vital, blood and plasma parameters) measured in 11 individual experimental studies at 6 different time points using 57 rats without and 63 rats with systemic inflammation following lipopolysaccharide infusion. For each rat, four group classifiers (treatment, survival, study, ID) were used to get valid samples by a later filtering of the statistical base. Any information about the hypothesis leading to the respective studies was suppressed. In order to assess whether a statistical relationship exists, a total of six different functional prototypes (linear and non-linear) were postulated and examined for their regression. Regression quality, correlation and significance were obtained in form of matrices. In our example, ultimately 510 300 regressions were optimized, automatically evaluated and filtered. The developed algorithm is able to reveal statistical relationships from a nearly crude database with low effort by systematic and unbiased analysis. The finding of well-known correlations proves its reliability, whose validity could be increased by clean aggregation of different studies. In addition, new interesting hints for future research could be gained. Thus, unknown markers can be found which are associated with an increased risk of death during systemic inflammation and sepsis. A further development of the program is planned including multiple regressions (more than two parameters could be related to each other) or cluster analysis.