bluuebunny/crossref_metadata_2025_split huggingface dataset:
Formigas (Hymenoptera, Formicidae) Associadas a Ninhos de Cornitermes cumulans Kollar (Isoptera, Termitidae) no Cerrado do Planalto Central do Brasil
Authors: Gallego Ropero María Cristina , Machado Feitosa Rodrigo , Pujol Luz Jose Roberto 
Published: April 2013

Com o objetivo de conhecer a fauna de formigas que coabita os cupinzeiros de Cornitermes cumulans (Kollar) no Cerrado sensu stricto do Brasil Central, foram realizadas coletas em 36 cupinzeiros em três localidades. Os cupinzeiros foram fragmentados e o material coletado foi armazenado em frascos com álcool a 80%. Apresentamos aqui uma lista das formigas associadas aos cupinzeiros de C. cumulans. Um total de 61 espécies distribuídas em nove subfamílias e 32 gêneros foi coletado. A subfamília Myrmicinae apresentou o maior número de gêneros (15) e de espécies (22). Estes resultados indicam que ninhos de cupins são importantes recursos de nidificação para várias espécies de formigas no Brasil Central.
Ants (Hymenoptera, Formicidae) Associated with Nests of Cornitermes cumulans (Kollar) (Isoptera, Termitidae) in the Cerrado of Central Brazil
Abstract. In order to survey the ant fauna inhabiting termite nests of Cornitermes cumulans (Kollar) in the Cerrado sensu stricto of Central Brazil, we collected inquiline ants in 36 termitaries in three localities. Termite mounds were fragmented and the ants collected and preserved in 80% ethanol. Here we present a list of the associated ants found in mounds of C. cumulans. A total of 61 species belonging to nine subfamilies and 32 genera were collected. The subfamily Myrmicinae had the largest number of genera (15) and species (22). The results indicate that termite mounds are an important nesting resource for several ant species in the Brazilian Cerrado.
Flexible Server Allocation and Customer Routing Policies for Two Parallel Queues When Service Rates Are Not Additive
Authors: Ahn Hyun-Soo , Lewis Mark E. 
Published: April 2013

We consider the question of how routing and allocation can be coordinated to meet the challenge of demand variability in a parallel queueing system serving two types of customers. A decision maker decides whether to keep customers at the station at which they arrived or to reroute them to the other station. At the same time, the decision maker has two servers and must decide where to allocate their effort. We analyze this joint decision-making scenario with both routing and station-dependent holding costs, but add an important twist. We allow the combined service rate (when the servers work at the same station) to be superadditive or subadditive. This captures positive or negative externalities that arise during collaboration. We seek an optimal control policy under the discounted or long-run average cost criteria. Our results show that in the superadditive case jobs should never be routed away from the lower-cost queue. When jobs are rerouted from the higher-cost queue to the low-cost queue the optimal control is monotone in the respective queue lengths. Moreover, we show that the optimal allocation is a nonidling priority rule based on the holding costs. In the subadditive case we find that the optimal policy need not exhibit such a simple structure. In fact, the optimal allocation need not prioritize one station (it may split the servers), and the optimal routing need not be monotone in the number of customers in each queue. We characterize the optimal policy for a few canonical cases and discuss why intuitive policies need not be optimal in the general case. An extensive numerical study examines the benefit of dynamically controlling both routing and resource allocation; we discuss when using one of the two levers—dynamic routing and dynamic allocation—is sufficient and when using both controls is warranted.
Energieautarker Drucksensor für Anwendungen im Automobil
Authors: Kurth Martin 
Published: April 2013

Zusammenfassung
Im Rahmen dieses Beitrags wird ein energieautarkes drahtloses Sensormikrosystem vorgestellt. Die Neuheit des drahtlosen Systems besteht darin, dass es als energieautarkes Sensorsystem speziell für den Einsatz in Fahrzeugen konzipiert worden ist. Der neu entwickelte energieautarke Drucksensor soll den Förderdruck im Kraftstoffsystem von Fahrzeugen drahtlos im 2,4-GHz-Frequenzband an einen Empfänger übertragen. Das energieautarke Sensorsystem wird durch einen kinematischen Wandler mit Energie versorgt, wobei ein Messwert übertragen wird, sobald ausreichend Energie im System vorhanden ist. Somit variiert die Systemdatenrate abhängig vom Systemenergieniveau. Da diese Art der Energieversorgung keine konstante Leistung an die Schaltung abgibt, ist eine spezielle Anpassschaltung, bzw. eine Spannungsversorgungsschaltung gefunden worden, die es erlaubt, den kinematischen Energiewandler an die Sensorschaltung anzupassen. Dabei wird ein Energiespeicher so lange mit Energie versorgt, bis ein bestimmter Schwellenwert erreicht ist. Dieser Schwellenwert wurde so festgelegt, dass für einen Druck- und Temperaturmesszyklus ausreichend Energie im Speicher vorhanden ist. Nach erfolgreicher Übertragung geht die Schaltung wieder in den Zustand des “Energiesammelns” über. Um einen möglichst kompakten Systemaufbau bestehend aus Drucksensor, Energiewandler mit Energiespeicher, Controller und HF Modul realisieren zu können, wurde eine Aufbauvariante in Form eines PCB/MID Trägerrahmens untersucht und dargestellt.
Kamerabasierte quantitative Messverfahren für die Silizium-Photovoltaik — Was Licht über Solarzellen erzählt
Authors: Kasemann Martin 
Published: April 2013

Zusammenfassung
Dieses Paper beschreibt die physikalischen Grundlagen neuer kamerabasierter Messtechniken für die Silizium-Photovoltaik. Die Methodenentwicklung zielt vor allem darauf ab, Bildintensitäten auf physikalische Standardkenngrößen (Strom, Spannung, Widerstand, Leistung) zurückführen. Dies erhöht — zumindest im Rahmen der Gültigkeit der teilweise vereinfachten physikalischen Modelle — die Aussagekraft und Vergleichbarkeit von Ergebnissen. Ausgewählte Beispiele zeigen, dass die Verfahren sowohl relevant für die Produktionskontrolle in der Solarindustrie sind, als auch wichtige neue Einsichten in die Solarzellen- und Halbleiterphysik bieten.
Bewegungszustandsbestimmung ungestützter MEMS-Beschleunigungssensoren
Authors: Keunecke Kristoph , Scholl Gerd 
Published: April 2013

Zusammenfassung
Ist der Bewegungszustand autonom agierender inertialer Navigationssysteme (INS) bekannt, lässt sich die Positioniergenauigkeit durch die Anwendung sog. Zero Velocity Updates (ZUPT) deutlich erhöhen. Verschwindet das Nutzsignal der Sensoren allerdings im Rauschen, was insbesondere bei langsamen Bewegungen der Fall ist, so hat die Schätzung des Bewegungszustandes anhand klassischer Verfahren der statistischen Signalanalyse über die Interpretation von Änderungen im Rauschsignal zu erfolgen. Dazu präsentiert dieser Artikel eine umfassende Charakterisierung dieser Verfahren anhand einfacher aber typischer Testszenarien.
Optische Erfassung dreidimensionaler Strukturen in einem globalen Referenzsystem
Authors: Schmitt Robert , Schönberg Alexander , Bertelsmeier Felix 
Published: April 2013

Zusammenfassung
Eine Herausforderung bei der Inbetriebnahme von Produktionsprozessen liegt in der Identifikation und Kompensation von Abweichungen zwischen einer virtuellen Planung und der realen Umsetzung. Diese Abweichungen können durch globale Referenzsysteme sichtbar gemacht und kompensiert werden. Dieser Beitrag beschreibt die Integration lokaler Sensorik und deren Daten in einem globalen Referenzsysteme am Beispiel eines flexiblen Lichtschnittsensors bestehend aus mehreren Kameras und einem Mehrlinien-Laserprojektor.
Ein störgrößenunterdrückendes optisches Messsystem auf Basis von Faser-Bragg-Gitter-Sensoren
Authors: Rößner Max R. , Heßke Andre , Kin Vitali , Koch Alexander W. 
Published: April 2013

Zusammenfassung
Faser-Bragg-Gitter können als optische Temperatur- und Dehnungssensoren, die in den Kern einer Glasfaser eingeschrieben sind, betrieben werden [1]. In bestimmten Anwendungen bieten sie Vorteile gegenüber konventionellen, elektrischen Sensoren [2]. Verglichen mit elektrischen Sensoren bringen faseroptische Messsysteme jedoch den großen technischen Aufwand der Wandlung von der optischen in die elektrische Domäne mit sich, zumal sich in der Regel die zusätzliche Aufgabe stellt, den Einfluss der nicht interessierenden Größe (Temperatur beziehungsweise Dehnung) in der Messung auszublenden. Die vorliegende Veröffentlichung stellt einen vereinfachten Aufbau vor, der Messungen mit Faser-Bragg-Gitter-Sensoren mit vergleichsweise geringem Aufwand ermöglicht und der zusätzlich die Möglichkeit bietet, temperatur- beziehungsweise dehnungskompensiert zu messen. Der Aufbau wurde sowohl simulativ als auch im Versuch überprüft.
Isolation and Diversity Analysis of Resistance Gene Homologues from Switchgrass
Authors: Zhu Qihui , Bennetzen Jeffrey L , Smith Shavannor M 
Published: April 2013

AbstractResistance gene homologs (RGHs) were isolated from the switchgrass variety Alamo by a combination of polymerase chain reaction and expressed sequence tag (EST) database mining. Fifty-eight RGHs were isolated by polymerase chain reaction and 295 RGHs were identified in 424,545 switchgrass ESTs. Four nucleotide binding site−leucine-rich repeat RGHs were selected to investigate RGH haplotypic diversity in seven switchgrass varieties chosen for their representation of a broad range of the switchgrass germplasm. Lowland and upland ecotypes were found to be less similar, even from nearby populations, than were more distant populations with similar growth environments. Most (83.5%) of the variability in these four RGHs was found to be attributable to the within-population component. The difference in nucleotide diversity between and within populations was observed to be small, whereas this diversity is maintained to similar degrees at both population and ecotype levels. The results also revealed that the analyzed RGHs were under positive selection in the studied switchgrass accessions. Intragenic recombination was detected in switchgrass RGHs, thereby demonstrating an active genetic process that has the potential to generate new resistance genes with new specificities that might act against newly-arising pathogen races.
Purifying Selection Causes Widespread Distortions of Genealogical Structure on the Human X Chromosome
Authors: O’Fallon Brendan 
Published: April 2013

AbstractThe extent to which selective forces shape patterns of genetic and genealogical variation is unknown in many species. Recent theoretical models have suggested that even relatively weak purifying selection may produce significant distortions in gene genealogies, but few studies have sought to quantify this effect in humans. Here, we employ a reconstruction method based on the ancestral recombination graph to infer genealogies across the length of the human X chromosome and to examine time to most recent common ancestor (TMRCA) and measures of tree imbalance at both broad and very fine scales. In agreement with theory, TMRCA is significantly reduced and genealogies are significantly more imbalanced in coding regions and introns when compared to intergenic regions, and these effects are increased in areas of greater evolutionary constraint. These distortions are present at multiple scales, and chromosomal regions as broad as 5 Mb show a significant negative correlation in TMRCA with exon density. We also show that areas of recent TMRCA are significantly associated with the disease-causing potential of site as measured by the MutationTaster prediction algorithm. Together, these findings suggest that purifying selection has significantly distorted human genealogical structure on both broad and fine scales and that few chromosomal regions escape selection-induced distortions.
Incidence of Rash After Amoxicillin Treatment in Children With Infectious Mononucleosis
Authors: Chovel-Sella Aluma , Ben Tov Amir , Lahav Einat , Mor Orna , Rudich Hagit , Paret Gideon , Reif Shimon 
Published: April 2013

BACKGROUND:“Ampicillin rash,” a phenomenon unique to patients with Epstein-Barr virus acute infectious mononucleosis (AIM) treated with ampicillin, was first reported in the 1960s. The incidence was estimated as being between 80% and 100%, and the figures have not been reviewed since those first accounts. We sought to establish the current incidence of rash associated with antibiotic treatment among children with AIM.METHODS:A retrospective study of all hospitalized children diagnosed as having AIM based upon positive Epstein-Barr virus serology in 2 pediatric tertiary medical centers in Israel.RESULTS:Of the 238 children who met the study entry criteria during the study period, 173 were treated with antibiotics. Fifty-seven (32.9%) of the subjects treated with antibiotics had a rash during their illness compared with 15 (23.1%) in untreated patients (P = .156; not significant). Amoxicillin was associated with the highest incidence of antibiotic-induced rash occurrence (29.5%, 95% confidence interval: 18.52–42.57), but significantly lower than the 90% rate reported for ampicillin in past studies. Age, gender, ethnicity, and atopic or allergic history were not associated with the development of rash after antibiotic exposure. Among the laboratory data, only increased white blood cell counts were more prevalent among subjects who did not develop an antibiotic-induced rash.CONCLUSIONS:The incidence of rash in pediatric patients with AIM after treatment with the current oral aminopenicillin (amoxicillin) is much lower than originally reported.
Association Between Total Duration of Breastfeeding and Iron Deficiency
Authors: Maguire Jonathon L. , Salehi Leila , Birken Catherine S. , Carsley Sarah , Mamdani Muhammad , Thorpe Kevin E. , Lebovic Gerald , Khovratovich Marina , Parkin Patricia C. ,   on behalf of the TARGet Kids! collaboration
Published: April 2013

OBJECTIVE:
To determine whether there is an association between the total breastfeeding duration and iron stores, iron deficiency, and iron deficiency anemia in healthy urban children.

METHODS:
A cross-sectional study of healthy children, aged 1 to 6 years, seen for primary health care between December 2008 and July 2011 was conducted through the TARGet Kids! practice-based research network. Univariate and adjusted regression analyses were used to evaluate an association between total breastfeeding duration and serum ferritin, iron deficiency, and iron deficiency anemia.

RESULTS:
Included were 1647 healthy children (median age 36 months) with survey, anthropometric, and laboratory data. An association was found between increasing duration of breastfeeding and lower serum ferritin (P = .0015). Adjusted logistic regression analysis revealed the odds of iron deficiency increased by 4.8% (95% confidence interval: 2%–8%) for each additional month of breastfeeding. Exploratory analysis suggested an increasing cumulative probability of iron deficiency with longer total breastfeeding duration with an adjusted odds ratio of 1.71 (95% confidence interval: 1.05–2.79) for iron deficiency in children breastfed over versus under 12 months of age. The relationship between total breastfeeding duration and iron deficiency anemia did not meet statistical significance.

CONCLUSIONS:
Increased total breastfeeding duration is associated with decreased iron stores, a clinically important association warranting additional investigation.
Effect of Slag on Mixing Time in Gas-Stirred Ladles Assisted with a Physical Model
Authors: Amaro-Villeda Adrián M. , Conejo A. , Ramírez-Argáez Marco A. 
Published: April 2013

ABSTRACTA 1/6th water physical model of a 140 tons gas-stirred steel ladle is used to evaluate mixing times (τm at 95% of chemical uniformity) in a two phase system without slag (air-water) and in a more realistic three phase system (air-water-oil) to simulate the argon-steel-slag system and quantify the effect of the slag layer on the mixing time. Slag layer is kept constant at 0.004 m. Mixing times are estimated through measured changes in pH due to the addition of a tracer (NaOH 1 M). The effect of the following variables on the mixing time is evaluated for a single injector: gas flow rate (7, 17 y 37 l/min) and the injector position (R/r= 0, 1/3, ½, 2/3 and 4/5). Experimental results obtained in this work show good agreement when compared against mixing time correlations reported by Mazumdar for the two phase air-water case (no slag considered). Another comparison is done using the new concept called “effective bath height” proposed by Barati, where the mixing time is a function of the size of the slag layer since this layer dissipates part of the total amount of stirring energy introduced into the ladle by the injection of gas. Agreement is not good in this case. Finally, an estimation of the percentage of the stirring energy dissipated by the slag is computed, including other factors that govern the dissipation of stirring energy. Percentage of energy dissipated by the slag is found to be between 2.7 to 12 % depending on the process conditions.
Decarburization of Hot-Rolled Non-Oriented Electrical Steels
Authors: Gutiérrez Emmanuel J. , Salinas Armando 
Published: April 2013

ABSTRACTThe high temperature decarburization-oxidation behavior of hot rolled, non-oriented electrical steel strips is investigated during air-annealing treatments. Annealing temperature and time are varied from 700 – 1050 °C and 10 to 150 min, respectively. The experimental results show that uniform external oxidation affects strongly the rate at which carbon can be removed from this material. The thickness of the oxide layer formed after 150 minutes of annealing increases linearly with increasing temperature in the range 828 and 920 °C. The effect of temperature on the thickness of the oxide scale at temperatures outside this range is significantly smaller. These results indicate that the rate of oxidation in this material is strongly influenced by the microstructure of the steel during annealing. Decarburization rates are very slow during annealing at T ≤ 750 °C where the oxide layer is thin and porous. In contrast, fast and intense decarburization of the strips is observed as a result of annealing at temperatures between 800 and 850 °C. Finally, decarburization at T ≥ 875 °C becomes slower as the temperature is increased until at T ≥ 950 °C this process is practically inhibited. Measurements of C content as a function of time and temperature show that the observed decarburization kinetics follows Wagner’s model at 800 and 850 °C. However, at higher annealing temperatures decarburization is slower than that predicted by the model. This behavior is related to the increment of the oxide scale thickness and a transition from cracked to crack-free oxide structure which makes C diffusion through the oxide film very difficult.
Mid-infrared silicon waveguide resonators with Q∼105 by using photonic crystal cavities
Authors: Lin Pao , Singh Vivek , Cai Yan , Patel Neil Sunil , Mu Jianwei , Zhang Lin , Kimerling Lionel , Agarwal Anuradha Murthy 
Published: April 2013

ABSTRACTOne dimensional photonic crystal 1D-PhC silicon waveguide resonators with quality factor, Q∼105, are demonstrated at mid-infrared wavelengths between 2 um to 5 um. Silicon has several advantages for mid-infrared applications including its broad mid-infrared transmission spectrum which extends out to 9 um, CMOS compatible fabrication processing, and ease of electronic-photonic integration. The proposed resonators are composed of photonic crystal cavities with optimized (i) lattice parameter a, (ii) cavity width w and (iii) hole radius r. Finite difference time domain (FDTD) simulations are used to adjust these three parameters, a, w, and r, to select a resonant frequency of interest within the mid-infrared spectral range. Due to the high quality factor Q, these PhC silicon waveguide resonators have much higher sensitivity as chemical sensors and have the potential to replace bulky instruments such as an FTIR.
Microstructure-based Simulations of the High-Strain-Rate Response of Heterogeneous Ti/Al/B Reactive Powder Mixtures
Authors: Gonzales Manny , Gurumurthy Ashok , Kennedy Gregory B. , Gokhale Arun M. , Thadhani Naresh N. 
Published: April 2013

ABSTRACTWe investigate the dynamic behavior under uniaxial stress loading conditions of heterogeneous mixtures of Ti/Al/B via impact simulations on simulated microstructures. We simulate a range of Al concentrations at a constant theoretical material density (TMD) to determine their effects on the mechanical response of a realistic microstructure to impact conditions. We also study particle-level effects such as mixing, extreme deformation, and hot spot formation due to void collapse, as a function of microstructure. Our goal is to shed light on the possible meso-scale phenomena that makes a certain mixture more reactive than others of variable Al composition.
Difference in elastic properties of CrB2 determined by microscopic and macroscopic measurements
Authors: Tanaka Katsushi , Tsutsui Satoshi , Okamoto Norihiko L. , Inui Haruyuki , Baron Alfred Q.R. 
Published: April 2013

ABSTRACTCrB2 possess the hexagonal AlB2 structure which belongs to the spacegroup of P6/mmm. The compound exhibits para- to antiferro-magnetic transition at about 88 K. By using a macroscopic measurement technique, that is, a conventional resonant ultrasound spectroscopy (RUS) with a millimeter size mono-crystal, significant elastic anomalies have been observed just above the magnetic transition temperature. On the other hand, elastic constants determined by a microscopic measurement technique, that is, an inelastic X-ray scattering method (BL35XU of SPring-8, Japan) do not show any elastic anomalies at around the transition temperature. In order to explain the discrepancy, we have introduced a kind of so called ΔE effect resulting from a multidomain structure. If crystal lattice is slightly deformed by a spontaneous magnetostriction in the antiferromagnetic state, the symmetry of crystal lattice is lowered from hexagonal to monoclinic when the symmetry of magnetic structure is taken into account. By the lowering of the symmetry, the crystal consists of six magnetic domains in the antiferro magnetic state. If magnetic domain boundaries move in response to externally applied stresses, the mechanical deformation is absorbed by nonelastic deformations induced by the movement of magnetic domain boundaries. This multidomain model well explains the experimental results obtained by both microscopic (X-ray) and macroscopic (ultrasound) measurements. The microscopic measurement technique is useful to obtain the true elastic properties of crystal lattice without effects coming from a multidomain structure.