bluuebunny/crossref_metadata_2025 huggingface dataset:
Disaccharide combinations and the expression of enolase3 and plasma membrane Ca2+ATPase isoform in sturgeon sperm cryopreservation
Authors: Xi MD , Li P , Du H , Qiao XM , Liu ZG , Wei QW
Published: January 2018

Contents

Acipenser sinensis and Acipenser dabryanus are critically endangered species, so germplasm conservation via cryopreservation of sperm is necessary. Disaccharides can act as membrane‐impermeable cryoprotectants, and enolase3 (ENO3) and plasma membrane Ca2+ ATPase isoform (PMCA2) are proteins associated with sperm quality. We considered seven characteristics of sperm quality in cultured brood stock from A. sinensis and A. dabryanus. We tested use of sucrose or trehalose alone and in combination at different concentrations for cryopreservation of A. dabryanus sperm. A low concentration of sucrose plus trehalose (S15T15) was optimal. Mixing of the extender with sucrose, lactose, or trehalose alone or with pairwise mixtures revealed that a mixture of lactose and trehalose (L15T15) gave the best results for both A. sinensis and A. dabryanus. Enolase3 and PMCA2 expression levels were measured in cryopreserved A. sinensis sperm via Western blotting. Relative ENO3 and PMCA2 expression levels were examined, and the relationship between disaccharide composition, sperm quality and protein expression was explored in A. sinensis. The results showed that relative ENO3 and PMCA2 expression levels were the highest at L15T15 in cryopreserved A. sinensis sperm. There were significant positive correlations between ENO3 expression and percentage membrane integrity, and between PMCA2 expression and sperm motility parameters (percentage of motile sperm, curvilinear velocity, straight‐line velocity and average path velocity; p < .05) in cryopreserved A. sinensis sperm. Our results indicate the optimal disaccharide combination and concentrations for cryopreservation of A. sinensis and A. dabryanus sperm and suggest that ENO3 and PMCA2 expression levels could serve as a valuable indicator of sperm quality in A. sinensis.
Predictors of beef calf temperament at weaning and its impact on temperament at breeding and reproductive performance
Authors: Kasimanickam VR , Abdel Aziz RL , Williams HM , Kasimanickam RK
Published: January 2018

Contents

Two experiments were conducted to determine (i) factors influencing calf temperament at weaning, (ii) association between heifer–calf temperament at weaning and temperament at breeding and (iii) effect of heifer–calf temperament on pregnancy rate per artificial insemination (P/AI). In experiment 1, beef cows and their calves (n = 285) from three farms were used. Sire docility estimated progeny difference (EPD) score, birth type (normal or assisted), calf gender, calf behaviour (during 1st 4 weeks) and calf health status (until weaning) were recorded. Cows and calves were assigned a temperament score (0—calm; 1—excitable), and all cows were given a body condition score (BCS, 1–9; 1—emaciated; 9—obese) at weaning. Calf's illness (p < .05), low sire docility EPD score (p < .05), altered gait (p < .05), altered resting behaviour (p < .01), reduced/no play behaviour (p < .05) and cow excitable temperament (p < .001) increased calf excitable temperament at weaning. In experiment 2, replacement heifer–calves (n = 758) from 12 farms were assigned a temperament score at weaning and later at breeding. Blood from 40 calves at weaning and 31 heifers at initiation of synchronization (same animals) was collected by coccygeal venipuncture for determination of circulating cortisol and substance P concentrations. Heifers were assigned a BCS and reproductive tract score (RTS, 1–5; 1—immature, acyclic; 5—mature, cyclic), synchronized for fixed time AI, observed for oestrus and were artificially inseminated. Cortisol concentrations were increased in excitable heifer–calves compared to calm heifer–calves at weaning (p < .05), and substance P was increased in excitable compared to calm females both at weaning and breeding (p < .05). Low sire EPD docility score (p < .01), heifer–calf excitable temperament at weaning increased excitable temperament at breeding (p < .01). Controlling for BCS categories (p < .01), oestrous expression (p < .0001) and temperament at breeding by oestrous expression (p < .05), the calf's excitable temperament at weaning (p < .001) reduced P/AI (Calm, 62.7 (244/389) vs. Excitable, 53.4% (197/369); p < .01). In conclusion, selection of docile cows and sires with greater docility EPD score should be given consideration to reduce calf excitement. Temperament in beef female can be detected earlier in their life and could be used as a tool in the selection process and to improve their performances.
Controls on the formation of stratabound dolostone bodies, Hammam Faraun Fault block, Gulf of Suez
Authors: Hirani Jesal , Bastesen Eivind , Boyce Adrian , Corlett Hilary , Gawthorpe Rob , Hollis Cathy , John Cédric M. , Robertson Hamish , Rotevatn Atle , Whitaker Fiona
Published: January 2018

Dolomitization is commonly associated with crustal‐scale faults, but tectonic rejuvenation, diagenetic overprinting and a fluid and Mg mass‐imbalance often makes it difficult to determine the dolomitization mechanism. This study considers differential dolomitization of the Eocene Thebes Formation on the Hammam Faraun Fault block, Gulf of Suez, which has undergone a simple history of burial and exhumation as a result of rifting. Stratabound dolostone bodies occur selectively within remobilized sediments (debrites and turbidites) in the lower Thebes Formation and extend into the footwall of, and for up to 2 km away from, the Hammam Faraun Fault. They are offset by the north–south trending Gebel fault, which was active during the earliest phases of rifting, suggesting that dolomitization occurred between rift initiation (26 Ma) and rift climax (15 Ma). Geochemical data suggest that dolomitization occurred from evaporated (ca 1·43 concentration) seawater at less than ca 80°C. Geothermal convection is interpreted to have occurred as seawater was drawn down surface‐breaching faults into the Nubian sandstone aquifer, convected and discharged into the lower Thebes Formation via the Hammam Faraun Fault. Assuming a ca 10 Myr window for dolomitization, a horizontal velocity of ca 0·7 m year−1 into the Thebes Formation is calculated, with fluid flux and reactivity likely to have been facilitated by fracturing. Although fluids were at least marginally hydrothermal, stratabound dolostone bodies do not contain saddle dolomite and there is no evidence of hydrobrecciation. This highlights how misleading dolostone textures can be as a proxy for the genesis and spatial distribution of such bodies in the subsurface. Overall, this study provides an excellent example of how fluid flux may occur during the earliest phases of rifting, and the importance of crustal‐scale faults on fluid flow from the onset of their growth. Furthermore, this article presents a mechanism for dolomitization from seawater that has none of the inherent mass balance problems of classical, conceptual models of hydrothermal dolomitization.
Genesis of island dolostones
Authors: Ren Min , Jones Brian
Published: January 2018

Cenozoic ‘island dolostones’ are found on islands throughout the oceans of the world. Due to their geological youth and lack of deep burial, these dolostones provide an opportunity to resolve some of the mysteries surrounding the dolomite problem. In island dolostone bodies, which are of variable size and variable dolomitization, the petrographic and geochemical properties of the dolostones are characterized by geographic and stratigraphic variations. In the larger island‐wide dolostone bodies, like those found on Grand Cayman, there are progressive increases in mole %Ca (%Camean: 53·9 to 57·6%), depletion of the heavier 18O and 13C isotopes (δ18Omean: 3·6 to 2·1‰ VPDB; δ13Cmean: 3·1 to 1·4‰ VPDB), and changes from fabric‐retentive to fabric‐destructive fabrics and a decrease in the amount of dolomite cement from the coastal areas towards the centres of the islands, similar to the Little Bahama Bank. These changes define geographically concentric zones that parallel the coastlines and reflect geochemical modification of the dolomitizing fluid through water–rock interactions, mixing with meteoric water and the changes in the rate and flux of seawater as it flowed from coasts to island interiors. The pattern of dolomitization, however, is not consistent from island to island because geographic and stratigraphic variations, specific to each island, influenced groundwater flow pattern (for example, geometry and size of the islands; the porosity and permeability of the precursor limestone), the duration of the dolomitization reaction, and other factors. The geographic extent of dolomitization and variation in dolomite stoichiometry of island dolostones may be comparable to the reaction stages established in high‐temperature laboratory experiments.
Morphometric analysis of slipface processes of an aeolian dune: Implications for grain‐flow dynamics
Authors: Cornwall Carin , Jackson Derek W. T. , Bourke Mary C. , Cooper J. Andrew G.
Published: January 2018

Grain flows are an integral part of sand dune migration; they are a direct response to the local wind regime and reflect complex interactions between localized over‐steepening of a dune slipface and complex turbulent airflow on the lee slope. Grain flows are primarily responsible for delivering sediment to the base of a dune, thus driving slipface advancement; yet, there are few constraints on their morphological and spatial characteristics or the amount of sediment that is redistributed by these flows. Using a combination of high‐resolution terrestrial laser scanning and video recordings, four distinct grain‐flow types are identified based on morphology and area on a dune slipface. Grain‐flow morphologies range from small, superficial flows to larger flows that affect greater portions of the slipface, moving significant amounts of sediment. Detailed field observations are presented of the dynamics of lee slopes, including measurements of the initiation location, thickness, magnitude and frequency statistics of grain flows, as well as volume estimates of redistributed sediment for each grain flow observed. High‐resolution laser scans enable accurate quantification of bulk sediment transfer from individual grain flows and can be used to study grain flows in a variety of environments. A categorization of grain‐flow morphologies is presented that links styles of flows with wind strength and direction, turbulent airflow, sediment deposition and environment.
Farmers’ Associations: Their Resources and Channels of Influence. Evidence from Poland
Authors: Milczarek‐Andrzejewska Dominika , Śpiewak Ruta
Published: January 2018

This article aims to contribute to the existing studies on the influence of interest groups on agricultural policies. The goal of the article is to assess the tangible and intangible resources of farmers’ associations in Poland, as well as the channels they use to influence agricultural policy. With this aim, an interdisciplinary model based on exchange theory was elaborated. The article draws on two empirical sources: first, in‐depth interviews with leaders; and secondly, a survey with members of these organisations. According to the leaders, farmers’ associations may influence agricultural policy only to a small degree. This results from their insufficient resources, especially those that are useful for politicians (e.g., expert knowledge). The second obstacle stems from the lack of unity and cooperation between these associations. However, members of farmers’ organisations paint a very different picture of farmers’ organisations: regardless of the type of organisation they belong to, they perceive it as very active and well‐endowed with tangible and intangible resources.
Patterns of burns and scalds in Mongolian children: a hospital‐based prospective study
Authors: Gerelmaa Gunsmaa , Tumen‐Ulzii Badarch , Nakahara Shinji , Ichikawa Masao
Published: January 2018

Objective

To describe the circumstances of burn injury occurrence among Mongolian children and the products involved.

Methods

Study participants were children aged 15 years and younger who were admitted to the Burn Unit of the National Trauma Orthopedic Research Center from August 2015 to July 2016. We collected data on participant demographics and the aetiology and clinical features of their burn injuries, and we analysed the data based on the NOMESCO Classification model.

Findings

Of 906 children, 83% were aged 0–3 years, 66% were injured around the cooking area in the traditional tent‐like dwelling called a ger or a detached house where no specified kitchen exists, and 28% were injured in a kitchen. Burn injuries resulted mostly from exposure to overflowing hot liquids (93%). Electric pots and electric kettles were the products most frequently involved in causing burn injuries (41% and 14%, respectively). Of 601 major burn injuries, 52% were due to electric pots. Moreover, burn injuries inflicted by electric pots were most likely to be major burn injuries (83%). Children typically fell into electric pots, while electric kettles were often pulled down by children.

Conclusion

Burn injuries among Mongolian children mainly occurred in cooking area of a ger involving electric pots. The current practice of cooking on the floor should be reconsidered for child burn prevention.
Clathrin and AP1 are required for apical sorting of glycosyl phosphatidyl inositol‐anchored proteins in biosynthetic and recycling routes in Madin‐Darby canine kidney cells
Authors: Castillon Guillaume A. , Burriat‐Couleru Patricia , Abegg Daniel , Criado Santos Nina , Watanabe Reika
Published: January 2018

Recently, studies in animal models demonstrate potential roles for clathrin and AP1 in apical protein sorting in epithelial tissue. However, the precise functions of these proteins in apical protein transport remain unclear. Here, we reveal mistargeting of endogenous glycosyl phosphatidyl inositol‐anchored proteins (GPI‐APs) and soluble secretory proteins in Madin‐Darby canine kidney (MDCK) cells upon clathrin heavy chain or AP1 subunit knockdown (KD). Using a novel directional endocytosis and recycling assay, we found that these KD cells are not only affected for apical sorting of GPI‐APs in biosynthetic pathway but also for their apical recycling and basal‐to‐apical transcytosis routes. The apical distribution of the t‐SNARE syntaxin 3, which is known to be responsible for selective targeting of various apical‐destined cargo proteins in both biosynthetic and endocytic routes, is compromised suggesting a molecular explanation for the phenotype in KD cells. Our results demonstrate the importance of biosynthetic and endocytic routes for establishment and maintenance of apical localization of GPI‐APs in polarized MDCK cells.
In vitroantimicrobial activity of narasin against common clinical isolates associated with canine otitis externa
Authors: Chan Wei Yee , Hickey Elizabeth E. , Khazandi Manouchehr , Page Stephen W. , Trott Darren J. , Hill Peter B.
Published: January 2018

Background

Antimicrobial resistance and antimicrobial stewardship are of ever‐increasing importance in veterinary medicine. Re‐purposing of old drugs that are not used in human medicine is one approach that addresses the emergence of multidrug resistance in canine skin and ear infections, and can reduce the use of critically important human antibiotic classes.

Hypothesis/Objectives

To determine the antimicrobial activity of narasin, a polyether ionophore conventionally used as a rumen modifier and anticoccidial agent in production animals, against common clinical isolates of canine otitis externa (OE).

Animals/Isolates

Clinical isolates (n= 110) from canine OE were tested, including 17 meticillin‐susceptibleStaphylococcus pseudintermedius(MSSP), 13 multidrug‐resistantStaphylococcus pseudintermedius(MDRSP), and 20 each of β‐haemolyticStreptococcusspp.,Pseudomonas aeruginosa,Proteus mirabilisandMalassezia pachydermatis.

Methods

Bacterial and yeast isolates were subcultured, suspended in broth and inoculated into 96‐well plates. Organisms were tested against concentrations of narasin ranging from 0.03 to 128 μg/mL. Minimal inhibitory concentrations (MICs) were determined after overnight incubation.

Results

NarasinMICs for staphylococcal and streptococcal isolates ranged from 0.06 to 0.25 μg/mL;MIC50andMIC90values for both organisms were 0.125 μg/mL. NoMICs were achieved forPseudomonasorProteusisolates. There was a weak antifungal effect againstM. pachydermatisisolates (MIC32 to >128 μg/mL).

Conclusions and Clinical Relevance

Narasin was effective against Gram‐positive bacteria and had antifungal activity at higher concentrations againstM. pachydermatis. However, the lack of Gram‐negative activity would prevent its use as a sole antimicrobial agent in cases of canine OE.
Influence of human acute wound fluid on the antibacterial efficacy of different antiseptic polyurethane foam dressings: An in vitro analysis
Authors: Rembe Julian‐Dario , Fromm‐Dornieden Carolin , Böhm Julia , Stuermer Ewa K.
Published: January 2018

Treating infected acute and/or chronic wounds still represents a major challenge in medical care. Various interactions of antiseptic dressings with wound environments regarding antimicrobial efficacy remain unclear. Therefore, this work aimed to investigate the influence of human acute wound fluid (AWF) on the antimicrobial performance of different antiseptic foam dressings in vitro against typical bacterial wound pathogens. Eight antiseptic polyurethane foam dressings containing either a silver formulation or a polyhexamethylene‐biguanide (PHMB) were assessed regarding their antimicrobial potency against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using a modified time‐kill assay based on ISO EN 20743. The antiseptic efficacy was evaluated standardly as well as under the influence of human AWF after 2, 4, 6, and 24 hours. The specific chemical formulation and concentration of the antiseptic substance (ionic or nanocrystalline silver, silver sulfadiazine, PHMB 0.1%/0.5%) embedded within the dressings seemed to play a key role. For certain dressings (two nanocrystalline and one ionic silver dressing), the antimicrobial efficacy was significantly reduced under the influence of AWF compared to unchallenged test series. Unchallenged the efficacy of PHMB was comparable to silver against P. aeruginosa and even significantly superior against S. aureus and E. coli. Challenged with AWF the reduction rates for silver adjusted or even exceeded (P. aeruginosa) those of PHMB. Within a challenging wound environment, especially some silver formulations demonstrated a reduced bacterial reduction. Regarding the presented in vitro results, the biomolecular interactions of antiseptic wound dressings with wound fluid should be part of more extensive investigations, considering varying factors such as bacterial species and wound (micro)environment to develop targeted therapeutic regimes for the individual.
Determination of Factors Related to Students’ Understandings of Heat, Temperature and Internal Energy Concepts
Authors: Gurcay Deniz , Gulbas Etna
Published: January 2018

The purpose of this research is to investigate the relationships between high school students’ learning approaches and logical thinking abilities and their understandings of heat, temperature and internal energy concepts. Learning Approach Questionnaire, Test of Logical Thinking and Three-Tier Heat, Temperature and Internal Energy Test were used as data collection tools in this research. All data collection tools were administered to 120 Anatolian High School students. The data collected through these tools were analyzed using descriptive statistics and stepwise multiple regression analysis. According to the results of this research, the variable that best predicts high school students’ understandings of heat, temperature and internal energy is their logical thinking abilities. Students’ logical thinking abilities and their orientations toward meaningful and rote learning predict 41% of the variance of their understanding scores concerning heat, temperature and internal energy. Results of the research indicate the importance of students’ logical thinking abilities and their orientations towards meaningful learning on their understandings of heat, temperature and internal energy concepts.
Developmental plasticity of GABAergic neurotransmission to brainstem motoneurons
Authors: Wollman Lila Buls , Levine Richard B. , Fregosi Ralph F.
Published: January 2018

Key points

Critical homeostatic behaviours such as suckling, swallowing and breathing depend on the precise control of tongue muscle activity.

Perinatal nicotine exposure has multiple effects on baseline inhibitory GABAergic neurotransmission to hypoglossal motoneurons (XIIMNs), consistent with homeostatic compensations directed at maintaining normal motoneuron output.

Developmental nicotine exposure (DNE) alters how GABAergic neurotransmission is modulated by acute activation of nicotinic acetylcholine receptors, which may provide insight into mechanisms by which nicotine exposure alters motor function under conditions that result in increased release of GABA, such as hypoxia, or endogenous acetylcholine, as occurs in the transition from NREM to REM sleep, or in response to exogenous nicotine.

Nicotinic acetylcholine receptor (nAChR) signalling regulates neuronal differentiation and synaptogenesis. Here we test the hypothesis that developmental nicotine exposure (DNE) disrupts the development of GABAergic synaptic transmission to hypoglossal motoneurons (XIIMNs). GABAergic spontaneous and miniature inhibitory postsynaptic currents (sIPSCs/mIPSCs) were recorded from XIIMNs in brainstem slices from control and DNE rat pups of either sex, 1–5 days old, at baseline and following acute stimulation of nAChRs with nicotine. At baseline, sIPSCs were less frequent and smaller in DNE cells (consistent with decreased action potential‐mediated GABA release), and mIPSCs were more frequent (consistent with increased vesicular GABA release from presynaptic terminals). Acute nicotine challenge increased sIPSC frequency in both groups, though the increase was greater in DNE cells. Acute nicotine challenge did not change the frequency of mIPSCs in either group, though mIPSC amplitude increased significantly in DNE cells, but not control cells. Stimulation of postsynaptic GABAA receptors with muscimol caused a significantly greater chloride current in DNE cells than in control cells. The increased quantal release of GABA, coupled with the rise in the strength of postsynaptic inhibition may be homeostatic adjustments to the decreased action‐potential‐mediated input from GABAergic interneurons. However, this will exaggerate synaptic inhibition under conditions where the release of GABA (e.g. hypoxia) or ACh (sleep‐wake transitions) is increased. These findings reveal a mechanism that may explain why DNE is associated with deficits in the ability to respond appropriately to chemosensory stimuli or to changes in neuromodulation secondary to changes in central nervous system state.
Origin of heterogeneous spiking patterns from continuously distributed ion channel densities: a computational study in spinal dorsal horn neurons
Authors: Balachandar Arjun , Prescott Steven A.
Published: January 2018

Key points

Distinct spiking patterns may arise from qualitative differences in ion channel expression (i.e. when different neurons express distinct ion channels) and/or when quantitative differences in expression levels qualitatively alter the spike generation process.

We hypothesized that spiking patterns in neurons of the superficial dorsal horn (SDH) of spinal cord reflect both mechanisms.

We reproduced SDH neuron spiking patterns by varying densities of KV1‐ and A‐type potassium conductances. Plotting the spiking patterns that emerge from different density combinations revealed spiking‐pattern regions separated by boundaries (bifurcations).

This map suggests that certain spiking pattern combinations occur when the distribution of potassium channel densities straddle boundaries, whereas other spiking patterns reflect distinct patterns of ion channel expression. The former mechanism may explain why certain spiking patterns co‐occur in genetically identified neuron types.

We also present algorithms to predict spiking pattern proportions from ion channel density distributions, and vice versa.

Neurons are often classified by spiking pattern. Yet, some neurons exhibit distinct patterns under subtly different test conditions, which suggests that they operate near an abrupt transition, or bifurcation. A set of such neurons may exhibit heterogeneous spiking patterns not because of qualitative differences in which ion channels they express, but rather because quantitative differences in expression levels cause neurons to operate on opposite sides of a bifurcation. Neurons in the spinal dorsal horn, for example, respond to somatic current injection with patterns that include tonic, single, gap, delayed and reluctant spiking. It is unclear whether these patterns reflect five cell populations (defined by distinct ion channel expression patterns), heterogeneity within a single population, or some combination thereof. We reproduced all five spiking patterns in a computational model by varying the densities of a low‐threshold (KV1‐type) potassium conductance and an inactivating (A‐type) potassium conductance and found that single, gap, delayed and reluctant spiking arise when the joint probability distribution of those channel densities spans two intersecting bifurcations that divide the parameter space into quadrants, each associated with a different spiking pattern. Tonic spiking likely arises from a separate distribution of potassium channel densities. These results argue in favour of two cell populations, one characterized by tonic spiking and the other by heterogeneous spiking patterns. We present algorithms to predict spiking pattern proportions based on ion channel density distributions and, conversely, to estimate ion channel density distributions based on spiking pattern proportions. The implications for classifying cells based on spiking pattern are discussed.
Effect of Soil-Structure Interaction on the Seismic Fragility of a Nuclear Reactor Building
Authors: El-Bahey Samer , Alzeni Yasser , Oikonomou Konstantinos
Published: January 2018

Recently, the nuclear industry has made a tremendous effort to assess the safety of nuclear power plants (NPP), as advances in seismology have led to the perception that the potential earthquake hazard in the U.S. may be higher than originally assumed. Due to the conservatism in the NPP design, structures and safety-related items are capable of withstanding earthquakes larger than the safe shutdown earthquake (SSE). One major aspect of conservatism in the design is ignoring the effect of soil-structure interaction (SSI), which results in conservative estimates of seismic demands for plant equipment. In this paper, a typical reactor building (RB) is chosen for a case study to investigate the potential benefit of accounting for SSI effects. A lumped mass stick model is first developed and analyzed with a fixed base configuration, using the free-field ground motion as input at the foundation level, as well as with a SSI configuration. Fragility analyses are then performed for the RB and one of its components to quantify the effects of the SSI on the overall seismic risk. In each case, a family of seismic fragility curves is developed. It is found that consideration of SSI effects in the analysis can improve the component fragilities, and potentially enhance the core damage frequency (CDF) of the plant.
Effect of Energy Management of a Grid Connected Photovoltaic/Battery/Load System on the Optimal Photovoltaic Placement on a National Scale: The Case of Turkey
Authors: Akdemir Huseyin , Durusu Ali , Erduman Ali , Nakir Ismail
Published: January 2018

Photovoltaic (PV) hybrid systems and their optimal energy management are still being actively studied. PV systems must be positioned at optimal tilt and azimuth angles to obtain maximum system performance. This paper presents the effect of energy management of a grid-connected PV-battery-load system on optimal PV placement using a linear programing (LP) method. The optimal placement of PV arrays aims to minimize the electricity cost of a fixed PV system for investors by considering monthly average daily global radiation, ambient temperature, wind speed, demand management constraints, and electricity tariffs in Turkey. The analysis is extended to consider 68 locations across Turkey. The analysis reveals that the optimal placement (optimal tilt and azimuth angle) can be different from that of previous studies because of multiple objective considerations. The optimal tilt angle results are lower than the local latitude in the range of 0 deg–8 deg in all regions. Furthermore, the optimal azimuth angle results are in the range of 6 deg–24 deg westbound throughout Turkey. These results can play a significant role for investments in the design of grid-connected PV-battery-load systems.
Geometric Algorithms for Robot Dynamics: A Tutorial Review
Authors: Park Frank C. , Kim Beobkyoon , Jang Cheongjae , Hong Jisoo
Published: January 2018

We provide a tutorial and review of the state-of-the-art in robot dynamics algorithms that rely on methods from differential geometry, particularly the theory of Lie groups. After reviewing the underlying Lie group structure of the rigid-body motions and the geometric formulation of the equations of motion for a single rigid body, we show how classical screw-theoretic concepts can be expressed in a reference frame-invariant way using Lie-theoretic concepts and derive recursive algorithms for the forward and inverse dynamics and their differentiation. These algorithms are extended to robots subject to closed-loop and other constraints, joints driven by variable stiffness actuators, and also to the modeling of contact between rigid bodies. We conclude with a demonstration of how the geometric formulations and algorithms can be effectively used for robot motion optimization.
Discussion of “Geometric Algorithms for Robot Dynamics: A Tutorial Review” (F. C. Park, B. Kim, C. Jang, and J. Hong, 2018, ASME Appl. Mech. Rev., 70(1), p. 010803)
Authors: Chirikjian Gregory S.
Published: January 2018

Lie-theoretic methods provide an elegant way to formulate many problems in robotics, and the tutorial by Park et al. (2018, “Geometric Algorithms for Robot Dynamics: A Tutorial Review,” ASME Appl. Mech. Rev., 70(1), p. 010803) is simultaneously a complete and concise introduction to these methods as they pertain to robot dynamics. The central reason why Lie groups are a natural mathematical tool for robotics is that rigid-body motions and pose changes can be described as Lie groups, and allow phenomena including robot kinematics and dynamics to be formulated in elegant notation without introducing superfluous coordinates. The emphasis of the tutorial by Park et al. (2018, “Geometric Algorithms for Robot Dynamics: A Tutorial Review,” ASME Appl. Mech. Rev., 70(1), p. 010803) is robot dynamics from a Lie-theoretic point of view. Newton–Euler and Lagrangian formulation of robot dynamics algorithms with O(n) complexity were formulated more than 35 years ago using recurrence relations that use the serial structure of manipulator arms. This was done without using the knowledge of Lie theory. But issues such as why the ω× terms in rigid-body dynamics appear can be more easily understood in the context of this theory. The authors take great efforts to be understandable by nonexperts and present extensive references to the differential-geometric and Lie-group-centric formulations of manipulator dynamics. In the discussion presented here, connections are made to complementary methods that have been developed in other bodies of literature. This includes the multibody dynamics, geometric mechanics, spacecraft dynamics, and polymer physics literature, as well as robotics works that present non-Lie-theoretic formulations in the context of highly parallelizable algorithms.
Analysis of Crank Angle-Resolved Vortex Characteristics Under High Swirl Condition in a Spark-Ignition Direct-Injection Engine
Authors: Zhao Fengnian , Ge Penghui , Zhuang Hanyang , Hung David L. S.
Published: January 2018

In-cylinder air flow structure makes significant impacts on fuel spray dispersion, fuel mixture formation, and flame propagation in spark ignition direct injection (SIDI) engines. While flow vortices can be observed during the early stage of intake stroke, it is very difficult to clearly identify their transient characteristics because these vortices are of multiple length scales with very different swirl motion strength. In this study, a high-speed time-resolved two-dimensional (2D) particle image velocimetry (PIV) is applied to record the flow structure of in-cylinder flow field along a swirl plane at 30 mm below the injector tip. First, a discretized method using flow field velocity vectors is presented to identify the location, strength, and rotating direction of vortices at different crank angles. The transients of vortex formation and dissipation processes are revealed by tracing the location and motion of the vortex center during the intake and compression strokes. In addition, an analysis method known as the wind-rose diagram, which is implemented for meteorological application, has been adopted to show the velocity direction distributions of 100 consecutive cycles. Results show that there exists more than one vortex center during early intake stroke and their fluctuations between each cycle can be clearly visualized. In summary, this approach provides an effective way to identify the vortex structure and to track the motion of vortex center for both large-scale and small-scale vortices.
Multimodel Control of Nonlinear Systems: An Improved Gap Metric and Stability Margin-Based Method
Authors: Ahmadi Mahdi , Haeri Mohammad
Published: January 2018

This paper presents a new multimodel controller design approach incorporating stability and performance criteria. The gap metric is employed to measure the distance between local models. An efficient method based on state feedback strategy is introduced to improve the maximum stability margin of the local models. The proposed method avoids local model redundancy, simplifies the multimodel controller structure, and supports employing of many linear control techniques, while does not rely on a priori experience to choose the gridding threshold value. To evaluate the proposed method, three benchmark nonlinear systems are studied. Simulation results demonstrate that the method provides the closed-loop stability and performance via a simple multimodel structure in comparison with the opponents.
Effect of Bifurcation on Thermal Characteristics of Convergent-Divergent Shaped Microchannel
Authors: Srivastava Pankaj , Dewan Anupam
Published: January 2018

A microchannel heat sink with convergent-divergent (CD) shape and bifurcation is presented, and flow and heat transfer characteristics are analyzed for Re ranging from 120 to 900. The three-dimensional governing equations for the conjugate heat transfer with temperature-dependent solid and fluid properties are solved using the finite volume method. Comparisons are carried out for four cases, namely, rectangular shape with and without bifurcation and CD shape with and without bifurcation. The pressure drop, flow structure, and average Nusselt number are analyzed in detail, and the thermal resistance and overall performance are compared. It is shown that the CD shape with bifurcation has more uniform and lower temperature at the bottom wall and better heat transfer performance compared to other geometries. The heat transfer augmentation in the CD shaped microchannel with bifurcation can be attributed not only to the accelerated and redirected flow toward the constant cross section segment but also to periodically interrupted and redeveloped thermal boundary-layers due to bifurcation. It is also shown that increasing Re leads to thinning of thermal boundary-layers resulting in an enhanced heat transfer in terms of an increased average Nusselt number from 38% to 74%. However, there is an increased pressure drop due to channel shape and obstacle in fluid flow. Further, due to a high pressure drop penalty at high Re, CD shaped microchannel with bifurcation loses its heat transfer effectiveness.
Differentiating metastatic lymph nodes in lung cancer patients based on endobronchial ultrasonography features
Authors: Lin Ching-Kai , Chang Lih-Yu , Yu Kai-Lun , Wen Yueh-Feng , Fan Hung-Jen , Ho Chao-Chi
Published: January 2018

Aim: The aim of this study was to identify easy and relatively effective ultrasound criteria for metastatic mediastinal lymph node prediction. Materials and methods: A retrospective chart review of patients who underwent endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) from March 2014 to September 2016 was performed. We used the following EBUS sonographic features for metastatic lymph node prediction: 1) length of the short axis, 2) shape, 3) margin, 4) echogenicity, 5) central hilar structure, and 6) coagulation necrosis sign. These sonographic findings were compared with the final pathology results or clinical follow-up. Results: A total of 227 lymph nodes were retrospectively evaluated in 133 lung cancer patients; 72% of the lymph nodes had been proven to be malignant metastasis. Logistic regression analysis revealed that the length of the short axis, shape, margin, and echogenicity were independent predictive factors for metastasis. We developed a sum score based on these four sonographic features. A larger sum score trended toward a greater possibility of malignancy. If all four predictive factors were preserved, the diagnostic accuracy, the value of the specificity and the positive predictive value of the sonographic feature would be higher than 90%. Conclusions: The sonographic features of EBUS are valuable tools in predicting metastatic lymph nodes in lung cancer patients.
Surface and interface properties of polar thin films on a ferroelectric substrate: ZnO on LiNbO3 (0001) and (0001¯)
Authors: Zhu Xiaodong , Altman Eric I.
Published: January 2018

The impact of ferroelectric polarization on film growth has been studied through the deposition of polar ZnO thin films on ferroelectric LiNbO3 (0001) and (0001¯) surfaces. The growth was monitored by reflection high energy electron diffraction and characterized by x-ray photoelectron spectroscopy (XPS), x-ray diffraction, and x-ray reflectivity. The evolution of the XPS peak intensities and x-ray reflectivity data suggest that the growth was Stranski–Krastanov with a two-dimensional to three-dimensional transition and a small degree of roughness at the interface. The film maintained the substrate surface crystallography initially, then transitioned to an ordered ZnO (0001) phase after passing through a disordered regime. Higher Zn 2p XPS core level binding energies were observed on positively poled LiNbO3 and were attributed to the negative compensating charges at the positive surface n doping the ZnO film, thereby the Fermi level is pinned at the bottom of the ZnO conduction band. In addition, the reaction of 2-propanol was used as a probe to identify the polarity of thick ZnO films. The results indicate that ZnO films grown on either LiNbO3 (0001) or (0001¯) polar surfaces ultimately develop a negative polarization. Therefore, it is concluded that the LiNbO3 polar substrate has a more obvious impact over a short range near the ZnO/LiNbO3 interface but this does not translate into directing the polarization direction of thicker ZnO films.
Reconfigurable nanoscale spin-wave directional coupler
Authors: Wang Qi , Pirro Philipp , Verba Roman , Slavin Andrei , Hillebrands Burkard , Chumak Andrii V.
Published: January 2018

We propose a nanoscale spin-wave directional coupler that allows the realization of magnonic integrated circuits.
An atom interferometer inside a hollow-core photonic crystal fiber
Authors: Xin Mingjie , Leong Wui Seng , Chen Zilong , Lan Shau-Yu
Published: January 2018

Matter-wave interference is demonstrated with light in a micrometer-size hollow-core photonic crystal fiber.
Dynamic traction of lattice-confined platinum atoms into mesoporous carbon matrix for hydrogen evolution reaction
Authors: Zhang Huabin , An Pengfei , Zhou Wei , Guan Bu Yuan , Zhang Peng , Dong Juncai , Lou Xiong Wen (David)
Published: January 2018

Platinum single atoms are loaded into mesoporous carbon spheres to give high electrocatalytic performance for hydrogen generation.
Stereochemistry and amyloid inhibition: Asymmetric triplex metallohelices enantioselectively bind to Aβ peptide
Authors: Guan Yijia , Du Zhi , Gao Nan , Cao Yue , Wang Xiaohui , Scott Peter , Song Hualong , Ren Jinsong , Qu Xiaogang
Published: January 2018

Metallosupramolecular complexes can enantioselectively target the central hydrophobic α/β discordant stretch of Aβ.
Toward biomass-derived renewable plastics: Production of 2,5-furandicarboxylic acid from fructose
Authors: Motagamwala Ali Hussain , Won Wangyun , Sener Canan , Alonso David Martin , Maravelias Christos T. , Dumesic James A.
Published: January 2018

A process for converting fructose to 2,5-furandicarboxylic acid, a monomer used in the production of a renewable plastics.
Precursors of human CD4
+
cytotoxic T lymphocytes identified by single-cell transcriptome analysis
Authors: Patil Veena S. , Madrigal Ariel , Schmiedel Benjamin J. , Clarke James , O’Rourke Patrick , de Silva Aruna D. , Harris Eva , Peters Bjoern , Seumois Gregory , Weiskopf Daniela , Sette Alessandro , Vijayanand Pandurangan
Published: January 2018

Human CD4
+
cytotoxic T lymphocytes that play a vital role in antiviral immunity are highly heterogeneous.
Endopeptidase PepO Regulates the SpeB Cysteine Protease and Is Essential for the Virulence of Invasive M1T1 Streptococcus pyogenes
Authors: Brouwer Stephan , Cork Amanda J. , Ong Cheryl-Lynn Y. , Barnett Timothy C. , West Nicholas P. , McIver Kevin S. , Walker Mark J.
Published: January 2018

Streptococcus pyogenes
(group A
Streptococcus
[GAS]) causes a wide range of human infections. The pathogenesis of GAS infections is dependent on the temporal expression of numerous secreted and surface-associated virulence factors that interact with host proteins. Streptococcal pyrogenic exotoxin B (SpeB) is one of the most extensively studied toxins produced by GAS, and the coordinate growth phase-dependent regulation of
speB
expression is linked to disease severity phenotypes. Here, we identified the endopeptidase PepO as a novel growth phase-dependent regulator of SpeB in the invasive GAS M1 serotype strain 5448. By using transcriptomics followed by quantitative reverse transcriptase PCR and Western blot analyses, we demonstrate through targeted mutagenesis that PepO influences growth phase-dependent induction of
speB
gene expression. Compared to wild-type and complemented mutant strains, we demonstrate that the 5448Δ
pepO
mutant strain is more susceptible to killing by human neutrophils and is attenuated in virulence in a murine model of invasive GAS infection. Our results expand the complex regulatory network that is operating in GAS to control SpeB production and suggest that PepO is a virulence requirement during GAS M1T1 strain 5448 infections.

IMPORTANCE
Despite the continuing susceptibility of
S. pyogenes
to penicillin, this bacterial pathogen remains a leading infectious cause of global morbidity and mortality. A particular subclone of the M1 serotype (M1T1) has persisted globally for decades as the most frequently isolated serotype from patients with invasive and noninvasive diseases in Western countries. One of the key GAS pathogenicity factors is the potent broad-spectrum cysteine protease SpeB. Although there has been extensive research interest on the regulatory mechanisms that control
speB
gene expression, its genetic regulation is not fully understood. Here, we identify the endopeptidase PepO as a new regulator of
speB
gene expression in the globally disseminated M1T1 clone and as being essential for virulence.
MALT1 Controls Attenuated Rabies Virus by Inducing Early Inflammation and T Cell Activation in the Brain
Authors: Kip E. , Staal J. , Verstrepen L. , Tima H. G. , Terryn S. , Romano M. , Lemeire K. , Suin V. , Hamouda A. , Kalai M. , Beyaert R. , Van Gucht S.
Published: January 2018

MALT1 is involved in the activation of immune responses, as well as in the proliferation and survival of certain cancer cells. MALT1 acts as a scaffold protein for NF-κB signaling and a cysteine protease that cleaves substrates, further promoting the expression of immunoregulatory genes. Deregulated MALT1 activity has been associated with autoimmunity and cancer, implicating MALT1 as a new therapeutic target. Although MALT1 deficiency has been shown to protect against experimental autoimmune encephalomyelitis, nothing is known about the impact of MALT1 on virus infection in the central nervous system. Here, we studied infection with an attenuated rabies virus, Evelyn-Rotnycki-Abelseth (ERA) virus, and observed increased susceptibility with ERA virus in MALT1
−/−
mice. Indeed, after intranasal infection with ERA virus, wild-type mice developed mild transient clinical signs with recovery at 35 days postinoculation (dpi). Interestingly, MALT1
−/−
mice developed severe disease requiring euthanasia at around 17 dpi. A decreased induction of inflammatory gene expression and cell infiltration and activation was observed in MALT1
−/−
mice at 10 dpi compared to MALT1
+/+
infected mice. At 17 dpi, however, the level of inflammatory cell activation was comparable to that observed in MALT1
+/+
mice. Moreover, MALT1
−/−
mice failed to produce virus-neutralizing antibodies. Similar results were obtained with specific inactivation of MALT1 in T cells. Finally, treatment of wild-type mice with mepazine, a MALT1 protease inhibitor, also led to mortality upon ERA virus infection. These data emphasize the importance of early inflammation and activation of T cells through MALT1 for controlling the virulence of an attenuated rabies virus in the brain.

IMPORTANCE
Rabies virus is a neurotropic virus which can infect any mammal. Annually, 59,000 people die from rabies. Effective therapy is lacking and hampered by gaps in the understanding of virus pathogenicity. MALT1 is an intracellular protein involved in innate and adaptive immunity and is an interesting therapeutic target because MALT1-deregulated activity has been associated with autoimmunity and cancers. The role of MALT1 in viral infection is, however, largely unknown. Here, we study the impact of MALT1 on virus infection in the brain, using the attenuated ERA rabies virus in different models of MALT1-deficient mice. We reveal the importance of MALT1-mediated inflammation and T cell activation to control ERA virus, providing new insights in the biology of MALT1 and rabies virus infection.