bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybrid model for renewable energy and loads prediction based on data mining and variational mode decomposition
Authors: Dou Chunxia , Zheng Yuhang , Yue Dong , Zhang Zhanqiang , Ma Kai
Published: March 2018

Accurate renewable resource and load forecasting plays a key role in the progress of power grid planning schemes. In this study, a hybrid short‐term forecasting method based K ‐means clustering and variational mode decomposition (VMD) technique is proposed to deal with the problem of forecasting accuracy. K ‐means clustering is a means of data mining approach and used for classifying data into several clusters. A cluster selection method is adopted to extract similar features from historical days. To better analyse the time series of historical data, VMD decomposes time series data into an ensemble of components with different frequencies. Self‐adaptive evolutionary extreme learning machine as a novel and fast regression tool is trained and used for predicting each component. Eventually, the forecasting result generated by reconstructing all the predicted components values. The performance of the proposed hybrid forecasting model is evaluated by using real data from National Renewable Energy Laboratory. The simulation results show that it can obtain better forecasting accuracy than some previously reported methods.
Visibility distance estimation in foggy situations and single image dehazing based on transmission computation model
Authors: Liu Jianlei
Published: March 2018

The existing visibility distance estimation algorithms in foggy situations use the region growing method to extract the vertical position of inflection point of image intensity changing. These algorithms have lower inflection point location accuracy for an image with a non‐homogeneous road surface. To deal with these problems, this study presents a novel visibility distance measuring technique under foggy weather conditions. This method combines two major models: inflection point estimation (IPE) model and transmission refining (TR) model. The proposed IPE model based on transmission computation model derives a very useful relation between the transmission value of inflection points and the constant . In order to acquire the more accurate transmission map and vertical position of each inflection point, this study establishes an effective TR model. This model exploits the edge information of input images, in order to significantly reduce the effects of artefact. The proposed algorithm provides more accurate visibility distance estimation of an image with a non‐homogeneous road surface than the well‐known algorithm through qualitative evaluations in experiments. The experimental results also show that the TR model has better outcomes than the guided filter approach through qualitative and quantitative evaluations.
Circularly polarised filtering dielectric resonator antenna for X‐band applications
Authors: Sahoo Anuj Kumar , Gupta Ravi Dutt , Parihar Manoj Singh
Published: March 2018

A circularly polarised filtering dielectric resonator antenna is proposed. Left hand circularly polarised electromagnetic field is generated by virtue of a rectangular ring slot present on the ground plane of the dielectric laminate, beneath the dielectric resonator antenna, which is fed by a 50 Ω microstrip line. Additionally, a semi‐elliptical shape bandpass filter is incorporated in the feed line to produce high selectivity, flat gain and wide stopband. A detailed analysis of the filter and the antenna has been carried out. The design offers fractional bandwidth of 6.13% ranging from 7.9 to 8.4 GHz, gain around 5.3 dBic and 3 dB axial ratio bandwidth of 3.68%. The simulated radiation efficiency is >80% in the pass band. The proposed structure has been fabricated and the results are compared with the simulated values.
Theoretical and experimental analysis of the solar collectors performances
Authors: Khelifa Abdelkrim , Touafek Khaled , Boutina Lyes , Mouhamed Tahar Baissi
Published: March 2018

Here, the authors present a theoretical and experimental study for the hybrid solar collector system photovoltaic thermal (PVT) compared to the conventional thermal collector CTH and the photovoltaic panel PV using a mathematical model that is developed in order to predict the performance of the system. The model is based on the equations of the energy balances of each system to see these thermal and electrical performances. The system studied consists of a PV panel welded above the outside face of a thermal system in order to cool the PV cells and increase their electrical efficiency. The results of the experimental study were compared with the theoretical data and the model was validated.
Non‐linear tip speed ratio cascade control for variable speed high power wind turbines: a backstepping approach
Authors: Wang Liangyong , Cao Linxi , Zhao Lei
Published: March 2018

This study presents a non‐linear tip speed ratio (TSR) cascade controller for high power wind turbines (WTs) considering the effects of the large rotor inertia and torsional behaviour of the shafts. A model‐based non‐linear rotor speed controller is proposed for the inner loop. The required speed reference is provided by an outer loop. A design procedure for cascade control of WTs is based on a backstepping design. It is shown that the above two‐loop control schemes lead to a nice cascade structure for the closed‐loop systems. Stability result adapted for analysis of this particular kind of systems is developed. The effectiveness of the proposed control approach is evaluated on a WT by comparing with typical control strategies such as non‐linear TSR control, optimal torque control, and sliding mode control. Simulation results show that the proposed two‐loop controller exhibits better performance than the above typical control strategies.
Introducing low‐order system frequency response modelling of a future power system with high penetration of wind power plants with frequency support capabilities
Authors: Krpan Matej , Kuzle Igor
Published: March 2018

Wind power generation has reached a significant share in power systems worldwide and will continue to increase. As the converter‐connected generation reduces the grid inertia, more and more interest has been given to exploiting the kinetic energy and controllability of variable‐speed wind turbine generators (VSWTGs) for frequency support. Consequently, the grid frequency dynamics are changing. Thus, it is necessary to include the frequency response of wind power plants in the system frequency response (SFR) model. A novel approach to low‐order SFR modelling of a future power system with a high share of frequency‐support‐capable VSWTGs has been presented. Low‐order model of VSWTGs with primary frequency response and natural inertial response has been developed considering different wind turbine operating regimes and compared to the non‐linear model for validation. Low‐order model has been presented in a symbolic transfer function form. Model accuracy has been discussed and the impact of VSWTG parameters on frequency response has been analysed. The developed model facilitates studying power system frequency dynamics by avoiding the need for modelling complex VSWTG systems, while retaining a satisfying level of accuracy.
Albumin nanoparticles fabricated from microscaled PLGA templates using layer‐by‐layer assembly
Authors: Zhao Qi , Fang Zhe‐Xiang , Chen Ming‐Mao , Li Min , Zhou Zhi‐Min , Du Bo , Zhang Qi‐Qing
Published: March 2018

The size of particles is a principal parameter to design drug delivery vehicles. In this work, albumin nanoparticles were fabricated from microscaled poly[lactic‐co‐(glycolic acid)] (PLGA) templates using layer‐by‐layer (LbL) assembly, which are different from traditional LbL‐based hollow capsules. The albumin nanoparticles exhibit a spherical shape and solid inner structure. The formation mechanism of these albumin nanoparticles was proposed based on PLGA templates, mechanical property of albumin and external sonication.
Pulmonary toxicity of exposure to nano nickel oxide
Authors: Chang Xuhong , Zhao Hongjun , Gao Jinxia , Chen Lijuan , Zhu An , Wang Cheng , Yu Shu , Ren Xiaolan , Ge Pengfei , Sun Yingbiao
Published: March 2018

Many articles have been reported in the literature on the relationship between exposure to nano nickel oxide (NiO) and pulmonary toxicity, but no coherent results have been achieved. This research is aimed at investigating the combined toxicity effects of pulmonary induced by nano NiO using meta‐analysis. Data of cell and rat models were retrieved according to included and excluded criteria from 1994 to 2016. Twenty one articles were chosen in the meta‐analysis. The standardised mean difference between the exposure and control groups was calculated from the different endpoints in cell and rat models, respectively. The meta‐estimate was calculated using the computational equations when the effect size is measured in different scales. The results found that nano NiO induced the increasing of lactate dehydrogenase and decreasing of cell viability. We found an abnormal change in bronchoalveolar lavage fluid including the raised number of total cells, neutrophils, alveolar macrophage, and chemokines, as well as the transient increasing of pro‐inflammation cytokines. In addition, most of the above‐mentioned indicators can be changed after exposure to nano NiO from 1 week to 3 months and recovering at 6 months. Nano NiO could induce pulmonary toxicity, hinting potential adverse effect on the human respiratory system.
Imagerie globale de la Terre par les ondes sismiques
Authors: Romanowicz Barbara
Published: March 2018

L’imagerie du manteau de la Terre est motivée par certaines questions fondamentales en géophysique, telle la compréhension des processus présents et passés de dynamique interne à l’origine de la tectonique des plaques.

Depuis une vingtaine d’années, l’étude de l’intérieur de la Terre connaît une véritable révolution, notamment grâce au développement de techniques toujours plus performantes de tomographie sismique et à la puissance de calcul rendue possible par l’informatique.

À l’heure actuelle, il est possible de calculer de manière précise le champ des ondes sismiques à travers des structures 3D arbitrairement complexes, en géométrie sphérique et pour des durées suffisantes, par des méthodes de calcul numérique, telle la méthode des « éléments spectraux ».
En 2017, le prix Nobel de physique ainsi que la médaille d’or du CNRS récompensent la détection des ondes gravitationnelles
Authors: Vilain Christiane
Published: March 2018

Alain Brillet (Artemis et Virgo) et Thibault Damour (IHES) se sont vu décerner chacun une médaille d’or, tandis que le prix Nobel a été partagé entre trois des principaux initiateurs et responsables du projet LIGO : une moitié a été attribuée à Rainer Weiss (MIT) et l’autre moitié à Barry Barish et Kip Thorne (tous deux de Caltech).
Anwendung der hyperthermen intrathorakalen Chemotherapie (HITHOC) in Deutschland
Authors: Ried Michael , Hofmann Hans-Stefan , Dienemann Hendrik , Eichhorn Martin
Published: March 2018

Hintergrund Die hypertherme intrathorakale Chemotherapie (HITHOC) wird seit mehreren Jahren an einigen thoraxchirurgischen Kliniken zusätzlich zur chirurgischen Zytoreduktion im Rahmen eines multimodalen Therapieansatzes zur Behandlung maligner Pleuratumoren angewendet. Genaue Zahlen zur HITHOC in Deutschland liegen bislang nicht vor.

Material und Methode Deutschlandweite schriftliche Umfrage an den thoraxchirurgischen Kliniken bzw. Abteilungen zu Anzahl, Indikationen, technischer Durchführung, perioperativen Schutzmaßnahmen und Komplikationen der HITHOC.

Ergebnis Insgesamt wurden 116 Kliniken angeschrieben. Die Rücklaufquote des Fragebogens lag bei 43% (n = 50). In 33 Kliniken wurde bisher keine HITHOC durchgeführt. Gründe hierfür sind mangelnde Ressourcen oder Erfahrung mit der HITHOC (n = 17), gefolgt von einer fehlenden Überzeugung bez. der Wirkung des Verfahrens (n = 8) verbunden mit einer zu hohen Komplikationsrate (n = 3). In 17 Kliniken wurden seit 2008 insgesamt 343 HITHOC-Prozeduren durchgeführt. Eine eigene Perfusionsmaschine besitzen 8 Kliniken, während sich die restlichen Kliniken die Maschine ausleihen. Indikationen stellten in allen Kliniken das maligne Pleuramesotheliom (n = 17), häufig Thymome mit pleuraler Aussaat (n = 11) und seltener die sekundäre Pleurakarzinose (n = 7) dar. Die HITHOC erfolgte in 16 Kliniken am geschlossenen Thorax, in den meisten Fällen bei 42 °C (n = 12) und für 60 Minuten (n = 15). Es wird immer Cisplatin entweder als Mono- (n = 9) oder in Kombinationstherapie (n = 8) verwendet. Alle Kliniken gaben als Ziel der HITHOC die Verbesserung der lokalen Tumorkontrolle sowie eine Verlängerung des rezidivfreien bzw. Gesamtüberlebens an. Über Komplikationen wird nur in wenigen Fällen berichtet.

Schlussfolgerung Die HITHOC wird derzeit an mindestens 17 Kliniken in Deutschland weitgehend standardisiert mit entsprechenden perioperativen Maßnahmen und ohne schwerwiegende Komplikationen durchgeführt. Ziel ist die Verbesserung der lokalen Tumorkontrolle bei bösartigen Neubildungen der Pleura und einer damit verbundenen Verbesserung der Überlebenszeit bei guter Lebensqualität.
Injuries in Austrian football players: Are they an issue?
Authors: Fischer Felix , Hoser Christian , Blank Cornelia , Schobersberger Wolfgang , Hepperger Caroline , Gföller Peter , Fink Christian
Published: March 2018

Purpose and Hypothesis With its load characteristics, the team sport of football places high physical demands on players and thus is associated with a high risk of injury. Therefore, the purpose of this study was to collect information about injuries suffered by football players in Austria during training or matches to enable participating clubs to learn about injuries.

Methods One hundred and forty-five players from seven teams with age ranging from 16 to 38 years participated in this prospective study during the 2015/16 season. Injury surveillance was conducted according to the consensus statement of Fuller et al. (2006).

Results During the period of study, a total of 83 injuries were recorded, which represents an overall incidence of 4.5 injuries/1000 hours (2.3 injuries/1000 hours in training and 14.2 injuries/1000 hours of match play). There was a significant difference for older age in injured players compared to non-injured players (p = 0.019). No differences in BMI were detected (p = 0.427). Ninety-four percent of all injuries occurred in the lower extremity, with the thigh (25.8 %), ankle (19.3 %) and knee (13.3 %) being the major locations of injuries. Muscle tendon injuries were the most common non-contact injuries (78.9 %).

Conclusion Lower extremity injuries are the most common injury in Austrian football. The incidence of muscle injuries is high, especially injuries of the posterior thigh. There are promising preventive strategies for the most common injury types. The implementation of these strategies is essential in order to reduce the incidence or recurrence of these football injuries.
Zweiter österreichischer Konsensus zur sicheren Anwendung von anti-TNF-α-Antikörpern bei chronisch-entzündlichen Darmerkrankungen
Authors: Miehsler Wolfgang , Dejaco Clemens , Gröchenig Hans-Peter , Fuchssteiner Harry , Högenauer Christoph , Kazemi-Shirazi Lili , Maier Harald , Mayer Andreas , Moschen Alexander , Reinisch Walter , Petritsch Wolfgang , Platzer Reingard , Steiner Pius , Tilg Herbert , Vogelsang Harald , Wenzl Heimo , Novacek Gottfried
Published: March 2018

Zusammenfasung

Anti-TNF-α-Antikörper haben die Therapie chronisch-entzündlicher Darmerkrankungen und anderer immunmediierter inflammatorischer Erkrankungen revolutioniert. Der zunehmende Einsatz dieser Substanzen war Anlass, den Konsensusbericht zur sicheren Anwendung von Infliximab der Arbeitsgruppe für Chronisch Entzündliche Darmerkrankungen der Österreichischen Gesellschaft für Gastroenterologie und Hepatologie aus dem Jahr 2010 zu aktualisieren und auf alle anti-TNF-α-Antikörper zu erweitern. Der vorliegende Konsensusbericht fasst die aktuelle Datenlage zur sicheren Anwendung von anti-TNF-α-Antikörpern zusammen und berücksichtigt folgende Themen: allgemeines Infektionsrisiko, bakterielle Infekte (inkl. Clostridium difficile, Tuberkulose, Nahrungsmittelhygiene), Pneumozystis jiroveci, virale Infektionen (inkl. Hepatitis B, Hepatitis C, HIV, CMV, VZV), Impfungen und Impfempfehlungen, gastrointestinale Aspekte (perianale Fistel, abdominale Fistel, Stenose), dermatologische Aspekte (Haut-Malignome, Ekzem-ähnliche anti-TNF-α-assoziierte Hautläsionen), Infusionsreaktionen und Immunogenität, demyelinisierende Erkrankungen, Hepatotoxizität, Hämatotoxizität, Herzinsuffizienz, Malignomrisiko und Einsatz nach Malignomen, sowie Schwangerschaft und Stillen. Da der Konsensusbericht als praktischer Leitfaden für die sichere Anwendung dieser Substanzen dienen soll, wurden die relevanten Aspekte in einer Checkliste zusammengefasst, die sich in zwei Teile „vor Therapie“ und „während Therapie“ gliedert.
Klinische Basisuntersuchung der Schulter
Authors: Friedrich Max , Wirtz Dieter , Rößler Philip
Published: March 2018

Zielsetzung Die erfolgreiche Behandlung von Schultererkrankungen erfordert eine exakte Diagnose. Neben einer differenzierten Anamneseerhebung stellt die klinische Untersuchung dabei den wichtigsten Bestandteil in der Diagnostik dar.

Methode Das vorliegende Video erklärt die gängigen Funktionsprüfungen und Provokationstests, die in der Basisuntersuchung der Schulter zum Einsatz kommen. Neben der Inspektion und Palpation liegt der Fokus hierbei auf den einzelnen Provokations- und Funktionstests.

Schlussfolgerung Der vorliegende Basisuntersuchungsgang ermöglicht eine strukturierte Herangehensweise an klinische Problemstellungen und kann, ergänzt um weitere spezifische und individuelle Tests, eine gute Grundlage für die Diagnostik von Schultererkrankungen darstellen.
Update Mammakarzinom 2017 – Etablierung neuer zielgerichteter Therapien
Authors: Lux Michael , Janni Wolfgang , Hartkopf Andreas , Nabieva Naiba , Taran Florin-Andrei , Overkamp Friedrich , Kolberg Hans-Christian , Hadji Peyman , Tesch Hans , Ettl Johannes , Huober Jens , Lüftner Diana , Wallwiener Markus , Müller Volkmar , Beckmann Matthias , Belleville Erik , Fehm Tanja , Wallwiener Diethelm , Brucker Sara , Schneeweiss Andreas , Fasching Peter
Published: March 2018

In den letzten Jahren sind zahlreiche neue Therapieoptionen für die Patientin mit einem Mammakarzinom in klinischen Studien entwickelt worden und teilweise zur Zulassung gekommen. Bei zunehmender Geschwindigkeit neuer Innovationen nimmt die Bedeutung von Kongressen zu, auf denen meist zum ersten Mal Daten zu den entsprechenden Therapien präsentiert werden. Diese Übersichtsarbeit greift Veröffentlichungen der Kongresse ASCO (American Society of Clincial Oncology) und ESMO (European Society of Medical Oncology) aus dem Jahr 2017 auf und fasst sie im Kontext bestehender Daten zusammen. Der Fokus liegt auf Erkenntnissen aus der neoadjuvanten Situation und Neuigkeiten aus der metastasierten Situation, wie dem Einsatz von CDK4/6-Inhibitoren oder PARP-Inhibitoren. Des Weiteren werden erste Ergebnisse zur Behandlung mit Checkpoint-Inhibitoren dargestellt. Bei baldigem Patentablauf von Trastuzumab sind zudem einige Studienergebnisse zu Trastuzumab-Biosimilars veröffentlicht worden. Auch die Digitalisierung der Patientenversorgung liefert erste Ergebnisse in Bezug auf Lebensqualität und Prognose von Patientinnen mit fortgeschrittener Krebserkrankung. Die digitale Kommunikation zwischen Patientin und Ärztin bzw. Arzt wird auch in Deutschland in einigen Studien untersucht. Bei anhaltender Diskussion über patientenrelevante Endpunkte für Patientinnen in der metastasierten Situation werden die Gesamtüberlebensdaten für die großen endokrin basierten Studien dringend erwartet. Erste Einblicke liefern vorläufige Analysen an kleinen Studienkollektiven. Im Rahmen der Patientenversorgung werden in den nächsten Jahren die Fragen aufkommen, welche Patientinnen besonders von bestimmten Therapien profitieren und welche vor besonders relevanten Nebenwirkungen geschützt werden können. Die Frage nach diesen Prädiktoren begleitet viele wissenschaftliche Projekte und bekommt eine besondere Aufmerksamkeit.
The history and future of the Japanese solar photovoltaic market
Authors: Cockbill Louisa
Published: March 2018

A comparative analysis of the Japanese PV market’s new legal framework looks to learn from past approaches to support sustainable grid connectivity and growth.
Psychophysical evidence for auditory motion parallax
Authors: Genzel Daria , Schutte Michael , Brimijoin W. Owen , MacNeilage Paul R. , Wiegrebe Lutz
Published: March 2018

Significance

When we cannot see a sound source, it is very difficult to estimate how far away it is. In vision, motion parallax facilitates depth perception in that when we move, nearer objects move more in our visual field than farther objects. Our experiments show that humans can also exploit motion parallax for sound sources. Moreover, we show that, as in the visual system, facilitation of auditory depth perception is stronger when the subjects move actively than when subjects are being moved or when only the sound sources move. We conclude that dedicated mechanisms exist that integrate self-motion with binaural auditory motion cues, allowing humans to exploit auditory motion parallax.
Modeling recovery curves with application to prostatectomy
Authors: Wang Fulton , Rudin Cynthia , Mccormick Tyler H , Gore John L
Published: March 2018

In many clinical settings, a patient outcome takes the form of a scalar time series with a recovery curve shape, which is characterized by a sharp drop due to a disruptive event (e.g., surgery) and subsequent monotonic smooth rise towards an asymptotic level not exceeding the pre-event value. We propose a Bayesian model that predicts recovery curves based on information available before the disruptive event. A recovery curve of interest is the quantified sexual function of prostate cancer patients after prostatectomy surgery. We illustrate the utility of our model as a pre-treatment medical decision aid, producing personalized predictions that are both interpretable and accurate. We uncover covariate relationships that agree with and supplement that in existing medical literature.
Biopanning data bank 2018: hugging next generation phage display
Authors: He Bifang , Jiang Lixu , Duan Yaocong , Chai Guoshi , Fang Yewei , Kang Juanjuan , Yu Min , Li Ning , Tang Zhongjie , Yao Pengcheng , Wu Pengcheng , Derda Ratmir , Huang Jian
Published: March 2018

The 2018 update of the biopanning data bank (BDB) stores phage display data sequenced by Sanger sequencing and next generation sequencing technologies. In this work, we upgraded the database with more biopanning data sets and several new features, including (i) incorporation of next generation biopanning data and the unselected population where the target is not determined and the round of screening is zero; (ii) addition of sequencing information; (iii) improvement of browsing and searching systems and 3 D chemical structure viewer; (iv) integration of standalone tools for target-unrelated peptides analysis within conventional phage display and next generation phage display (NGPD) data. In the current version of BDB (released on 19 January 2018), the database houses 3291 sets of biopanning data collected from 1540 published articles, including 95 NGPD data sets and 3196 traditional biopanning data sets. The BDB database serves as an important and comprehensive resource for developing peptide ligands.

Database URL: The BDB database is available at http://immunet.cn/bdb
Almost Positive Curvature on an Irreducible Compact Rank 2 Symmetric Space
Authors: DeVito Jason , Nance Ezra
Published: March 2018

A Riemannian manifold is said to be almost positively curved if the set of points for which all two-planes have positive sectional curvature is open and dense. We show that the Grassmannian of oriented two-planes in $\mathbb{R}^{7}$ admits a metric of almost positive curvature, giving the first example of an almost positively curved metric on an irreducible compact symmetric space of rank greater than 1. The construction and verification rely on the Lie group $\mathbf{G}_{2}$ and the octonions, so do not obviously generalize to any other Grassmannians.
Down-Regulated Expression of Magnesium Transporter Genes Following a High Magnesium Diet Attenuates Sciatic Nerve Crush Injury
Authors: Chen Ying-Ju , Cheng Fu-Chou , Chen Chun-Jung , Su Hong-Lin , Sheu Meei-Ling , Sheehan Jason , Pan Hung-Chuan
Published: March 2018

BACKGROUND

Magnesium supplementation has potential for use in nerve regeneration. The expression of some magnesium transporter genes is reflective of the intracellular magnesium levels.

OBJECTIVE

To assess the expression of various magnesium transporter genes as they relate to neurological alterations in a sciatic nerve injury model.

METHODS

Sciatic nerve injury was induced in rats, which were then fed either basal or high magnesium diets. Magnesium concentrations and 5 magnesium transporter genes (SLC41A1, MAGT1, CNNM2, TRPM6, and TRPM7) were measured in the tissue samples.

RESULTS

The high magnesium diet attenuated cytoskeletal loss in a dose-dependent manner in isolated nerve explants. The high magnesium diet augmented nerve regeneration and led to the restoration of nerve structure, increased S-100, and neurofilaments. This increased regeneration was consistent with the improvement of neurobehavioral and electrophysiological assessment. The denervated muscle morphology was restored with the high magnesium diet, and that was also highly correlated with the increased expression of desmin and acetylcholine receptors in denervated muscle. The plasma magnesium levels were significantly elevated after the animals consumed a high magnesium diet and were reciprocally related to the down-regulation of CNNM2, MagT1, and SCL41A1 in the blood monocytes, nerves, and muscle tissues of the nerve crush injury model.

CONCLUSION

The increased plasma magnesium levels after consuming a high magnesium diet were highly correlated with the down-regulation of magnesium transporter genes in monocytes, nerves, and muscle tissues after sciatic nerve crush injury. The study findings suggest that there are beneficial effects of administering magnesium after a nerve injury.
Severe Community-Acquired Pneumonia due to Acinetobacter baumannii in North America: Case Report and Review of the Literature
Authors: Serota David P , Sexton Mary Elizabeth , Kraft Colleen S , Palacio Federico
Published: March 2018

Acinetobacter baumannii is a rare but emerging cause of fulminant community-acquired pneumonia (CAP-AB). We describe a patient from a rural area who developed acute respiratory distress syndrome and septic shock. We describe risk factors and characteristics of this syndrome and review published cases of CAP-AB from North America.
Effects of dietary chlortetracycline, Origanum essential oil, and pharmacological Cu and Zn on growth performance of nursery pigs
Authors: Feldpausch J A , Amachawadi R G , Tokach M D , Scott H M , Dritz S S , Goodband R D , Woodworth J C , DeRouchey J M
Published: March 2018

Two 47-d experiments were conducted with 21-d-old weaned pigs (PIC 1050, initially 6.1 kg) to determine the effects of feeding low or high doses of chlortetracycline (CTC) and antibiotic alternatives (Cu, Zn, and essential oil [EO]), alone or in combination, on growth performance. On d 5 postweaning, pens of 5 pigs were allotted to diet treatments with 8 (exp. 1) or 7 (exp. 2) replicate pens per treatment. In exp. 1, treatments were fed from d 5 to 26 postweaning and arranged in a 2 × 3 factorial with main effects of added ZnO (0 vs. 2,500 ppm of Zn) and CTC (0, 55, or 441 ppm). In exp. 2, treatments were fed from d 5 to 33 and structured in a (2 × 2 × 2) + 2 factorial with main effects of added CuSO4 (0 vs. 125 ppm Cu), added ZnO (0 vs. 3,000 ppm Zn from d 5 to 12 and 2,000 ppm Zn from d 12 to 33), and Regano EX (0 vs. 0.1% Regano EX containing 5% Origanum oil). The 2 additional treatments were subtherapeutic (55 ppm) and therapeutic (441 ppm) levels of CTC. Following the treatment period, a common diet without antimicrobial was fed until d 47. All diets contained 16.5 ppm Cu and 110 ppm Zn from the trace mineral premix. In exp. 1, no ZnO × CTC interactions were observed. Feeding ZnO increased (P < 0.05) ADG, ADFI, and BW during the treatment period and increased (P < 0.05) ADG and ADFI overall (d 5 to 47). Pigs fed CTC had increased (linear, P < 0.05) ADG, ADFI, and BW during the treatment period and had marginally significant increases (linear, P < 0.10) in overall ADG and ADFI, but overall G:F tended (quadratic, P = 0.070) to increase then decrease as CTC increased. During the treatment period in exp. 2, EO did not affect ADG or ADFI, whereas pharmacological levels of Cu, Zn, and CTC increased (P < 0.05) ADG with coinciding increases (P = 0.055, 0.006, and linear 0.079, respectively) in ADFI. Copper, Zn, and CTC did not affect G:F. EO decreased (P = 0.009) G:F. Diet treatments had minimal carryover effects on subsequent nursery pig growth performance. Overall from d 5 to 47, Cu increased (P = 0.018) ADG, Zn increased (P < 0.05) ADG and ADFI, and EO tended to decrease (P = 0.086) G:F. In conclusion, increased dietary Cu, Zn, or CTC improved weanling pig performance while EO elicited no growth benefits. The benefits of added Zn from ZnO and CTC were additive and could be included together in diets to maximize growth performance of weaned pigs.
Temperature is a key driver of a wildlife epidemic and future warming will increase impacts
Authors: Price Stephen J. , Leung William T.M. , Owen Chris , Sergeant Chris , Cunningham Andrew A. , Balloux Francois , Garner Trenton W.J. , Nichols Richard A.
Published: March 2018

Increasing environmental temperatures are predicted to have increasingly severe and deleterious effects on biodiversity. For the most part, the impacts of a warming environment are presumed to be direct, however some predict increasingly severe disease epidemics, primarily from vector-borne pathogens, that will have the capacity to deplete host populations. Data to support this hypothesis are lacking. Here we describe increasing severity of ranavirosis driven by increasing temperature affecting a widely distributed amphibian host. Both in vitro and in vivo experiments showed that increasing environmental temperature leads to increased propagation of ranavirus and, in the latter, increased incidence of host infection and mortality. Also, temperature was shown to be a key determinant of disease dynamics in wild amphibians, raising the odds and severity of disease incidents. The direction of this effect was highly consistent in the context of other interacting variables such as shading around ponds. Projections based on future climate indicate that changes in seasonal weather in the UK will result in the increased incidence of severe cases of ranavirosis in amphibian populations that could affect recruitment. These complementary lines of evidence present a clear case of direct environmental modulation of a host-pathogen interaction and provide information for proposing mitigation actions.
Dynamic integration of multisensory turn commands supports active reorienting during ongoing navigation
Authors: Currier Timothy A. , Nagel Katherine I.
Published: March 2018

A longstanding goal of systems neuroscience is to quantitatively describe how the brain integrates cues from multiple modalities over time. Here we develop a closed-loop orienting paradigm inDrosophilato study the algorithms by which stimuli from different modalities are combined during ongoing navigation. We show that flies faced with an attractive visual and an aversive mechanosensory cue exhibit sequential responses, first turning away from the co-localized stimuli before turning back toward them. We also find that the presence of the aversive cue slows flies’ turns toward the attractive target, suggesting that conflicting unimodal turn commands are summed to produce multisensory turns of intermediate velocity. We then test a series of computational frameworks and find that integration is best described by a model in which multimodal stimuli are continuously and dynamically scaled, converted into turn commands, and then summed to produce ongoing orientation behavior.
Optimizing Disease Surveillance with Blockchain
Authors: Coelho Flávio Codeço
Published: March 2018

Disease surveillance, especially for infectious diseases, is a complex and inefficient process. Here we propose an optimized, blockchain-based monitoring and reporting process which can achieve all the desired features of an ideal surveillance system while maintaining costs down and being transparent and robust. We describe the technical specifications of such a solution and discuss possibilities for its implementation. Finally, the impact of the adoption of distributed ledger technology for disease surveillance is discussed.
Zika Virus Outbreak, Barbados, 2015 – 2016
Authors: Ryan Sadie J. , Lippi Catherine A. , Carlson Colin J. , Stewart-Ibarra Anna M. , Borbor-Cordova Mercy J. , Romero Moory M. , Cox Shelly-Ann , Mahon Roché , Trotman Adrian , Rollock Leslie , Gittens-St. Hilaire Marquita , King Desmond , Daniel Stephen
Published: March 2018

Barbados is a Caribbean island country of approximately 285,000 people, with a thriving tourism industry. In 2015, Zika spread rapidly throughout the Americas, and its proliferation through the Caribbean islands followed suit. Barbados reported its first confirmed autochthonous Zika transmission to the Pan American Health Organization (PAHO) in January 2016, a month before the global public health emergency was declared. Following detection of suspected Zika cases on Barbados in 2015, 926 individuals were described as suspected cases, and 147 lab confirmed cases were reported through December 2016, the end of the most recent epidemiological year. In this short report, we describe the epidemiological characteristics of 926 clinical case records which were originally suspected as cases of Zika, and which were subsequently sent for testing and confirmation; 147 were found positive for Zika, using RT-PCR methods, another 276 tested negative, and the remaining 503 were either pending results or still in the suspected category. Women were represented at about twice the rate of men in case records where sex was reported (71.9%), and confirmed cases (78.2%), and 19 of the confirmed positive cases were children under the age of 10.
Characterization of Diverse Homoserine Lactone Synthases inEscherichia coli
Authors: Daer René , Barrett Cassandra , Melendez Ernesto Luna , Wu Jiaqi , Tekel Stefan , Xu Jimmy , Dennison Brady , Muller Ryan , Haynes Karmella
Published: March 2018

Quorum sensing networks have been identified in over one hundred bacterial species to date. A subset of these networks regulate group behaviors, such as bioluminescence, virulence, and biofilm formation, by sending and receiving small molecules called homoserine lactones (HSLs). Bioengineers have incorporated quorum sensing pathways into genetic circuits to connect logical operations. However, the development of higher-order genetic circuitry is inhibited by crosstalk, in which one quorum sensing network responds to HSLs produced by a different network. Here, we report the construction and characterization of a library of ten synthases including some that are expected to produce HSLs that are incompatible with the Lux pathway, and therefore show no crosstalk. We demonstrated their function in a common lab chassis,Escherichia coliBL21, and in two contexts, liquid and solid agar cultures, using decoupled Sender and Receiver pathways. We observed weak or strong stimulation of a Lux Receiver by longer-chain or shorter-chain HSL-generating Senders, respectively. We also considered the under-investigated risk of unintentional release of incompletely deactivated HSLs in biological waste. We found that HSL-enriched media treated with bleach is still bioactive, while autoclaving deactivates LuxR induction. This work represents the most extensive comparison of quorum sensing synthases to date and greatly expands the bacterial signaling toolkit while recommending practices for disposal based on empirical, quantitative evidence.
Dynamic Kinetochore Size Regulation Promotes Microtubule Capture and Chromosome Biorientation in Mitosis
Authors: Sacristan Carlos , Ahmad Misbha , Keller Jenny , Fermie Job , Groenewold Vincent , Tromer Eelco , Fish Alexander , Melero Roberto , Carazo José María , Klumperman Judith , Musacchio Andrea , Perrakis Anastassis , Kops Geert JPL
Published: March 2018

Faithful chromosome segregation depends on the ability of sister kinetochores to attach to spindle microtubules. An outer layer of the kinetochore known as the fibrous corona transiently expands in early mitosis and disassembles upon microtubule capture. Neither the functional importance nor the mechanistic basis for this are known. Here we show that the dynein adaptor Spindly and the RZZ kinetochore complex drive fibrous corona formation in a dynein-independent manner. C-terminal farnesylation and MPS1 kinase activity cause conformational changes of Spindly that promote oligomerization of RZZ:Spindly complexes into a corona-like meshwork in cells and in vitro. Concurrent with corona expansion, Spindly potentiates corona shedding by recruiting dynein via three conserved short linear motifs. Expanded, non-sheddable fibrous coronas engage in extensive, long-lived lateral microtubule interactions that persist to metaphase and result in fused sister kinetochores, formation of merotelic attachments and chromosome segregation errors in anaphase. Thus, dynamic kinetochore size regulation in mitosis is coordinated by a single, Spindly-based mechanism that promotes initial microtubule capture and subsequent correct maturation of attachments.
Transcription-driven Chromatin Repression of Intragenic Promoters
Authors: Nielsen Mathias , Ard Ryan , Leng Xueyuan , Ivanov Maxim , Kindgren Peter , Pelechano Vicente , Marquardt Sebastian
Published: March 2018

Progression of RNA polymerase II (RNAPII) transcription relies on the appropriately positioned activities of elongation factors. The resulting profile of factors and chromatin signatures along transcription units provides a “positional information system” for transcribing RNAPII. Here, we investigate a chromatin-based mechanism that suppresses intragenic initiation of RNAPII transcription. We demonstrate that RNAPII transcription across gene promoters represses their function in plants. This repression is characterized by reduced promoter-specific molecular signatures and increased molecular signatures associated with RNAPII elongation. The FACT histone chaperone complex is required for this repression mechanism. Genome-wide mapping of Transcription Start Sites (TSSs) reveals thousands of discrete intragenic TSS positions in FACT mutants. Histone 3 lysine 4 mono-methylation poises exonic sites to initiate RNAPII transcription in FACT mutants. Uncovering the mechanism for intragenic TSS repression through the act of RNAPII elongation has important implications for understanding pervasive RNAPII transcription and the regulation of transcript isoform diversity.
Experimental loss of generalist plants reveals alterations in plant-pollinator interactions and a constrained flexibility of foraging
Authors: Biella Paolo , Akter Asma , Ollerton Jeff , Tarrant Sam , Janeček Štěpán , Jersáková Jana , Klečka Jan
Published: March 2018

Species extinctions undermine ecosystem functioning but species do not disappear at random. Ecosystem dynamics are ruled by a subset of dominant species, but it is not clear how losing several of these key species would affect plant-pollinator interactions. We tested how the experimental loss of the most highly visited generalist plants would affect flower visitor abundances (visitation) and pollinator effectiveness (quantity of pollen-tubes within pistils) in several sites. Significant changes in the plant-pollinator communities were detected. Firstly, visitation decreased after removing 1-2 most visited plants, suggesting that these species mostly facilitate other plants by keeping high flower visitor abundances in the sites. Nevertheless, we recorded within-site variations of these trends, especially among sampled transects and among plant species, suggesting that complex facilitation-competition interactions occur among plants, but that these vary among transects within the same sites. Pollinator effectiveness fluctuated but not in a clear linear way and was not directly linked to changes of flower visitation. This suggests that fluctuations of pollinator effectiveness might be due to destabilization of the pollinators by the removal of key resources. In addition, we detected a constrained flexibility of the foraging of flower visitors because they did not switch among flower shapes and they favoured specific plant traits such as high sugar content, small inflorescences and taller plants. Indeed, these constraints would eventually limit utilisation of new resources after perturbations, possibly undermining the stability of the system. In conclusion, our work demonstrates that the loss of dominant, highly generalist plants alters plant-pollinator interactions with implications for pollination and insect foraging. Therefore, in order to preserve ecosystems, generalist plants should not get lost, because they sustain the complex pattern of interactions between plants and flower visitors.
A genome-wide scan for correlated mutations detects macromolecular and chromatin interactions in Arabidopsis thaliana
Authors: Perlaza-Jiménez Laura , Walther Dirk
Published: March 2018

The concept of exploiting correlated mutations has been introduced and applied successfully to identify interactions within and between biological macromolecules. Its rationale lies in the preservation of physical interactions via compensatory mutations. With the massive increase of available sequence information, approaches based on correlated mutations have regained considerable attention.

We analyzed a set of 10,707,430 single nucleotide polymorphisms detected in 1,135 accessions of the plant Arabidopsis thaliana. To measure their covariance and to reveal the global genome-wide sequence correlation structure of the Arabidopsis genome, the adjusted mutual information has been estimated for each possible pair of polymorphic sites. We developed a series of filtering steps to account for genetic linkage and lineage relations between Arabidopsis accessions, as well as transitive covariance as possible confounding factors. We show that upon appropriate filtering, correlated mutations prove indeed informative with regard to molecular interactions, and furthermore, appear to reflect on chromosomal interactions.

Our study demonstrates that the concept of correlated mutations can also be applied successfully to within-species sequence variation and establishes a promising approach to help unravel the complex molecular interactions in A. thaliana and other species with broad sequence information.
Dendritic NMDA receptors in parvalbumin neurons enable strong and stable neuronal assemblies
Authors: Cornford Jonathan , Mercier Marion S , Leite Marco , Magloire Vincent , Häusser Michael , Kullmann Dimitri M
Published: March 2018

Parvalbumin-expressing (PV+) GABAergic interneurons mediate feedforward and feedback inhibition and have a key role in gamma oscillations and information processing. The importance of fast synaptic recruitment, action potential initiation and repolarization, and rapid synchronous GABA release by PV+ cells is well established. In contrast, the functional significance of PV+ cell NMDA receptors (NMDARs), which generate relatively slow postsynaptic currents, is unclear. Underlining their importance, several studies implicate PV+ cell NMDAR disruption in impaired network function and circuit pathologies. Here, we show that dendritic NMDARs underlie supralinear integration of feedback excitation from local pyramidal neurons onto mouse CA1 PV+ cells. Furthermore, by incorporating NMDARs at feedback connections onto PV+ cells in spiking networks, we show that these receptors enable cooperative recruitment of PV+ interneurons, strengthening and stabilising principal cell assemblies. Failure of this phenomenon provides a parsimonious explanation for cognitive and sensory gating deficits in pathologies with impaired PV+ NMDAR signalling.
Quantifying how constraints limit the diversity of viable routes to adaptation
Authors: Yeaman Sam , Gerstein Aleeza C. , Hodgins Kathryn A. , Whitlock Michael C.
Published: March 2018

Convergent adaptation can occur at the genome scale when independently evolving lineages use the same genes to respond to similar selection pressures. These patterns provide insights into the factors that facilitate or constrain the diversity of genetic responses that contribute to adaptive evolution. A first step in studying such factors is to quantify the observed amount of repeatability relative to expectations under a null hypothesis. Here, we formulate a novel metric to quantify the constraints driving the observed amount of repeated adaptation in pairwise contrasts based on the hypergeometric distribution, and then generalize this for simultaneous analysis of multiple lineages. This metric is explicitly based on the probability of observing a given amount of repeatability by chance under an arbitrary null hypothesis, and is readily compared among different species and types of trait. We also formulate a metric to quantify the effective proportion of genes in the genome that have the potential to contribute to adaptation. As an example of how these metrics can be used to draw inferences, we assess the amount of repeatability observed in existing datasets on adaptation to antibiotics in yeast and climate in conifers. This approach provides a method to test a wide range of hypotheses about how different kinds of factors can facilitate or constrain the diversity of genetic responses observed during adaptive evolution.
SESCA: Predicting Circular Dichroism Spectra from Protein Molecular Structures
Authors: Nagy Gabor , Igaev Maxim , Hoffmann Søren V. , Jones Nykola C. , Grubmüller Helmut
Published: March 2018

Circular dichroism spectroscopy is a highly sensitive, but low-resolution technique to study the structure of proteins. Combined with molecular modelling or other complementary techniques, CD spectroscopy can provide essential information at higher resolution. To this end, we introduce a new computational method to calculate the electronic circular dichroism spectra of proteins from a structural model or ensemble using the average secondary structure composition and a pre-calculated set of basis spectra. We compared the predictive power of our method to existing algorithms – namely DichroCalc and PDB2CD – and found that it predicts CD spectra more accurately, with a 50% smaller average deviation from the measured CD spectra. Our results indicate that the derived basis sets are robust to experimental errors in the reference spectra and to the choice of the secondary structure classification algorithm. For over 80% of the globular reference proteins, our basis sets accurately predict the experimental spectrum solely from their secondary structure composition. For the remaining 20%, correcting for intensity normalization considerably improves the prediction power. Additionally, we show that the predictions for short peptides and intrinsically disordered proteins strongly benefit from accounting for side-chain contributions and structural flexibility.

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