bluuebunny/crossref_metadata_2025 huggingface dataset:
Approximation Algorithm for a Heterogeneous Vehicle Routing Problem
Authors: Bae Jungyun , Rathinam Sivakumar
Published: August 2015

This article addresses a fundamental path planning problem which aims to route a collection of heterogeneous vehicles such that each target location is visited by some vehicle and the sum of the travel costs of the vehicles is minimal. Vehicles are heterogeneous as the cost of traveling between any two locations depends on the type of the vehicle. Algorithms are developed for this path planning problem with bounds on the quality of the solutions produced by the algorithms. Computational results show that high quality solutions can be obtained for the path planning problem involving four vehicles and 40 targets using the proposed approach.
Affordance Learning Based on Subtask's Optimal Strategy
Authors: Min Huaqing , Yi Chang'an , Luo Ronghua , Bi Sheng , Shen Xiaowen , Yan Yuguang
Published: August 2015

Affordances define the relationships between the robot and environment, in terms of actions that the robot is able to perform. Prior work is mainly about predicting the possibility of a reactive action, and the object's affordance is invariable. However, in the domain of dynamic programming, a robot's task could often be decomposed into several subtasks, and each subtask could limit the search space. As a result, the robot only needs to replan its sub-strategy when an unexpected situation happens, and an object's affordance might change over time depending on the robot's state and current subtask. In this paper, we propose a novel affordance model linking the subtask, object, robot state and optimal action. An affordance represents the first action of the optimal strategy under the current subtask when detecting an object, and its influence is promoted from a primitive action to the subtask strategy. Furthermore, hierarchical reinforcement learning and state abstraction mechanism are introduced to learn the task graph and reduce state space. In the navigation experiment, the robot equipped with a camera could learn the objects' crucial characteristics, and gain their affordances in different subtasks.
The Trending Academic Library Job Market: An Analysis of Library Position Announcements from 2011 with Comparisons to 1996 and 1988
Authors: Triumph Therese F. , Beile Penny M.
Published: August 2015

The primary objective of the study was to describe the number, types and titles, requested qualifications and skills, salary information, and locations of positions advertised in 2011 on the ALA JobLIST and ARL Job Announcements websites and in the print version of the Chronicle of Higher Education for purposes of determining the current state of the academic library job market in the United States. To investigate changes in the academic library job market and identify emerging trends over a 23-year period, results also were compared to studies that analyzed position announcements from 1996 and 1988. Content analysis of 957 unique academic library job advertisements revealed relative stasis in the market regarding the number of positions advertised, presence of administrative duties, geographic distribution of positions, and, to some extent, educational requirements. However, other comparisons were more dynamic. Specifically, there has been a decline in foreign language skills and prior work experience requirements over time while computer skills are increasingly sought. Perhaps most striking is the proliferation of new position titles that have emerged over time, which serves as an indication that library positions are becoming increasingly specialized.
Noninvasive cerebral oximetry during carotid endarterectomy: application and results
Authors: Kontrimavičiūtė Eglė , Kuzminskaitė Vilma , Šipylaitė Jūratė
Published: August 2015

Background. Cerebral monitoring during carotid endarterectomy allows to detect brain hypoperfusion following carotid clamping and hyperperfusion after restoring the blood flow. Immediate corrections of these changes have the potential in reducing adverse neurologic outcomes. In this study we share our experience using cerebral oximetry in carotid endarterectomy surgery, as well as finding a connection between comorbidities and baseline cerebral oxygenation values.
Materials and methods. A non-randomised perspective study was performed at Vilnius University Hospital Santariškių Clinics. During 2012–2013 all consecutive elective patients undergoing carotid surgery were enrolled in the study.
Results. No difference was found in the baseline values on the operative and control sides (71.15% vs 76.76%, p = 0.15). After carotid clamping regional brain saturation decreased by 4.34% of the baseline on the operative side. During the clamping cerebral oxygenation was lower on the operative side (68.06% vs 77.32%, p = 0.03). Following carotid declamping the difference between operative and control side oxygenation diminished (73.57% vs 79.30%, p = 0.16). Neither diabetes nor peripheral atherosclerosis had influence on baseline cerebral oxygen saturation values. There was a tendency towards the lower cerebral oxygenation baseline for smokers (70.12% vs 76.54%, p = 0.103).
Conclusions. Cerebral oximetry is a valuable method of cerebral monitoring reflecting changes in brain perfusion during carotid endarterectomy. Certain comorbidities might have a role in affecting baseline oximetry values.
ŽIV-1 dažniausios mutacijos ir atsparumas antiretrovirusiniams vaistams
Authors: Subočiūtė-Stuliova Tatjana , Griškevičius Algirdas , Gorobecas Aleksandras , Pumputienė Ingrida , Mauricas Mykolas
Published: August 2015

Tyrimo tikslas. Įvertinti ŽIV infekuotiems pacientams skirtingų ŽIV-1 mutacijų pasiskirstymą ir jų nulemtą atsparumą antiretrovirusiniams vaistams (ARV).
Metodai. Mutacijų tipai ir atsparumas vaistams buvo tiriami 149 ŽIV-1 infekuotiems pacientams, kurių kraujo plazmos mėginiai 2011– 2013  m. ištirti Nacionalinėje visuomenės sveikatos priežiūros laboratorijoje. ŽIV-1 genotipas ir atsparumas vaistams tirtas pacientams, kurių plazmos virusinis krūvis buvo ne mažesnis 2 000 kopijų/ml. Nustatytų ŽIV-1 mutacijų, sukeliančių atsparumą specifiniams ARV preparatams, duomenys buvo vertinami „HIV-1 Genotyping System Software  v2.8“, tiesiogiai prisijungus prie „Stanford HIV Drug Resistance Database“ (http://hivdb.stanford.edu), kur buvo tikrinama sekų kokybė ir nustatomas viruso potipis.
Rezultatai. Su atsparumu ARV susiję mutacijos buvo aptiktos 84 pacientams, o iš jų atsparumas vaistams (tiek faktinis, tiek potencialus) – 37 pacientams. Dažniausia aptiktos mutacijos, lemiančios atsparumą proteazių inhibitoriams (PI), buvo L10V, L10IV, L10N, L10I, A71V. Šios mutacijos buvo nustatytos kartu su atsparumo nukleozidiniams atvirkštinės transkriptazės inhibitoriams (NATI) ir nenukleozidiniams atvirkštinės transkriptazės inhibitoriams (NNATI) mutacijomis. Dažniausios atsparumo NATI mutacijos buvo A62V ir V75L, o NNATI mutacijos – V179D, G190S, K103N ir E138A, kurios ir pavienės, ir kartu su kitomis mutacijomis lemia tam tikro lygio atsparumą vaistams.
Išvados. Lietuvoje gydomiems ŽIV infekuotiems asmenims būdinga šio viruso mutacijų įvairovė: su atsparumu susietos ir su nustatytu atsparumu vaistams (25 % tyrime dalyvavusių asmenų); su atsparumu susietos, bet be nustatyto atsparumo vaistams (32  % tyrime dalyvavusių asmenų).
Prieš paskiriant gydymą ŽIV infekuotiems asmenims svarbu nustatyti atsparumą ARV lemiančias mutacijas ir tęsti atsparumo ARV tyrimus jau gydomiems pacientams.
On the enhancement of the Indian summer monsoon drying by Pacific multidecadal variability during the latter half of the twentieth century
Authors: Salzmann M. , Cherian R.
Published: August 2015

The observed summertime drying over Northern Central India (NCI) during the latter half of the twentieth century is not reproduced by the Coupled Model Intercomparison Project Phase 5 (CMIP5) model ensemble average. At the same time, the spread between precipitation trends from individual model realizations is large, indicating that internal variability potentially plays an important role in explaining the observed trend. Here we show that the drying is indeed related to the observed 1950–1999 positive trend of the Pacific Decadal Oscillation (PDO) index and that the relationship is even stronger for a simpler index (S1). Adjusting the CMIP5‐simulated precipitation trends to account for the difference between the observed and simulated S1 trend increases the original multimodel average NCI drying trend from −0.09 ± 0.31 mm d−1 (50 years)−1 to −0.54 ± 0.40 mm d−1 (50 years)−1. Thus, our estimate of the 1950–1999 NCI drying associated with Pacific decadal variability is of similar magnitude as our previous CMIP5‐based estimate of the drying due to anthropogenic aerosol. The drying (moistening) associated with increasing (decreasing) S1 can partially be attributed to a southeastward (northwestward) shift of the boundary between ascent and descent affecting NCI. This shift of the ascent region strongly affects NCI but not Southeast Asia and south China. The average spread between individual model realizations is only slightly reduced when adjusting for S1 as smaller‐scale variability also plays an important role.
Assessing the impacts of assimilating IASI and MOPITT CO retrievals using CESM‐CAM‐chem and DART
Authors: Barré Jérôme , Gaubert Benjamin , Arellano Avelino F. J. , Worden Helen M. , Edwards David P. , Deeter Merritt N. , Anderson Jeffrey L. , Raeder Kevin , Collins Nancy , Tilmes Simone , Francis Gene , Clerbaux Cathy , Emmons Louisa K. , Pfister Gabriele G. , Coheur Pierre‐François , Hurtmans Daniel
Published: August 2015

We show the results and evaluation with independent measurements from assimilating both MOPITT (Measurements Of Pollution In The Troposphere) and IASI (Infrared Atmospheric Sounding Interferometer) retrieved profiles into the Community Earth System Model (CESM). We used the Data Assimilation Research Testbed ensemble Kalman filter technique, with the full atmospheric chemistry CESM component Community Atmospheric Model with Chemistry. We first discuss the methodology and evaluation of the current data assimilation system with coupled meteorology and chemistry data assimilation. The different capabilities of MOPITT and IASI retrievals are highlighted, with particular attention to instrument vertical sensitivity and coverage and how these impact the analyses. MOPITT and IASI CO retrievals mostly constrain the CO fields close to the main anthropogenic, biogenic, and biomass burning CO sources. In the case of IASI CO assimilation, we also observe constraints on CO far from the sources. During the simulation time period (June and July 2008), CO assimilation of both instruments strongly improves the atmospheric CO state as compared to independent observations, with the higher spatial coverage of IASI providing better results on the global scale. However, the enhanced sensitivity of multispectral MOPITT observations to near surface CO over the main source regions provides synergistic effects at regional scales.
Interpretations of bullying by bullies, victims, and bully‐victims in interactions at different levels of abstraction
Authors: Pouwels J. Loes , Scholte Ron H. J. , van Noorden Tirza H. J. , Cillessen Antonius H. N.
Published: August 2015

According to the Social Information Processing Model of children's adjustment, children develop general interpretation styles for future social events based on past social experiences. Previous research has shown associations between interpretations of social situations and internalizing and externalizing symptoms. This study investigated whether bullies, victims, bully‐victims, and uninvolved children interpreted ambiguous human interactions differently in terms of bullying and whether these interpretations generalized to abstract non‐human interactions. Participants were 390 children (49% girls,Mage = 10.3 years) who completed self‐report measures of bullying and victimization. In addition, they indicated whether video fragments of positive, negative, or ambiguous interactions between humans, animals, and abstract figures depicted bullying situations. Bully‐victims reported more bullying than victims and uninvolved children in ambiguous abstract figure, animal, and human fragments and in positive animal fragments. Children who bully did not differ from the other groups. These findings indicate that interpretations of bullying generalized from ambiguous human interactions to more abstract ambiguous animal and abstract figure interactions. Implications for further research and practice were discussed. Aggr. Behav. 42:54–65, 2016. © 2015 Wiley Periodicals, Inc.
Recent Advances in Electrospun Nanofibrous Scaffolds for Cardiac Tissue Engineering
Authors: Zhao Guoxu , Zhang Xiaohui , Lu Tian Jian , Xu Feng
Published: August 2015

Cardiovascular diseases remain the leading cause of human mortality worldwide. Some severe symptoms, including myocardial infarction and heart failure, are difficult to heal spontaneously or under systematic treatment due to the limited regenerative capacity of the native myocardium. Cardiac tissue engineering has emerged as a practical strategy to culture functional cardiac tissues and relieve the disorder in myocardium when implanted. In cardiac tissue engineering, the design of a scaffold is closely relevant to the function of the regenerated cardiac tissues. Nanofibrous materials fabricated by electrospinning have been developed as desirable scaffolds for tissue engineering applications because of the biomimicking structure of protein fibers in native extra cellular matrix. The versatilities of electrospinning on the polymer component, the fiber structure, and the functionalization with bioactive molecules have made the fabrication of nanofibrous scaffolds with suitable mechanical strength and biological properties for cardiac tissue engineering feasible. Here, an overview of recent advances in various electrospun scaffolds for engineering cardiac tissues, including the design of advanced electrospun scaffolds and the performance of the scaffolds in functional cardiac tissue regeneration, is provided with the aim to offer guidance in the innovation of novel electrospun scaffolds and methods for improving their potential for cardiac tissue engineering applications.
Magnetically Induced Fog Harvesting via Flexible Conical Arrays
Authors: Peng Yun , He Yaxu , Yang Shuai , Ben Shuang , Cao Moyuan , Li Kan , Liu Kesong , Jiang Lei
Published: August 2015

Water is the driving force of all nature. Securing freshwater has been one of the most important issues throughout human history, and will be important in the future, especially in the next decade. Fog is ubiquitous in nature and is therefore considered as an alternative and sustainable freshwater resource. Nature has long served as a source of inspiration to develop new fog‐harvesting technologies. However, the collection of freshwater from static fog is still a challenge for the existing bio‐inspired fog‐harvesting systems. Herein, magnetically induced fog harvesting under windless conditions through the integration of cactus‐inspired spine structures and magnetically responsive flexible conical arrays is reported. Under an external magnetic field, static fog can be spontaneously and continuously captured and transported from the tip to the base of the spine due to the Laplace pressure difference. This work demonstrates the advantage of collecting fog water, especially in windless regions, which provides a new avenue for fog harvesting and can serve as a source of inspiration to further optimizations of existing fog‐water‐harvesting strategies.
Temperature‐Sensitive Hydrogel‐Particle Films from Evaporating Drops
Authors: Still Tim , Yunker Peter J. , Hanson Kasey , Davidson Zoey S. , Lohr Matthew A. , Aptowicz Kevin B. , Yodh A. G.
Published: August 2015

A simple method to prepare temperature‐sensitive films composed of micrometer‐sized colloidal hydrogel particles using evaporating drops of colloidal suspensions is demonstrated. The films range in thickness from a monolayer to approximately fifty particle diameters depending on initial particle volume fraction. Sessile droplets of hydrogel‐particle suspensions are evaporated on silicon wafers. The film is formed from particles spread densely over the air–water interface which then cross‐link and are deposited on the surface during the evaporation process. The resultant thin films exhibit a temperature‐responsiveness characteristic of the individual particles permitting modulation of size, shape, porosity, and optical transmission.
Preparation of an Immobilized Lipase‐Palladium Artificial Metalloenzyme as Catalyst in the Heck Reaction: Role of the Solid Phase
Authors: Filice Marco , Romero Oscar , Aires Antonio , Guisan Jose M. , Rumbero Angel , Palomo Jose M.
Published: August 2015

A p‐nitrophenylphosphonate palladium pincer was synthesized and selectively inserted by irreversible attachment on the catalytic serine of different commercial lipases with good to excellent yields in most cases. Among all, lipase from Candida antarctica B (CAL‐B) was the best modified enzyme. The artificial metalloenzyme CAL‐B‐palladium (Pd) catalyst was subsequently immobilized on different supports and by different orienting strategies. The catalytic properties of the immobilized hybrid catalysts were then evaluated in two sets of Heck cross‐coupling reactions under different conditions. In the first reaction between iodobenzene and ethyl acrylate, the covalent immobilized CAL‐B‐Pd catalyst resulted to be the best one exhibiting quantitative production of the Heck product at 70 °C in dimethylformamide (DMF) with 25% water and particularly in pure DMF, where the soluble Pd pincer was completely inactive. A post‐immobilization engineering of catalyst surface by its hydrophobization enhanced the activity. The selectivity properties of the best hybrid catalyst were then assessed in the asymmetric Heck cross‐coupling reaction between iodobenzene and 2,3‐dihydrofuran retrieving excellent results in terms of stereo‐ and enantioselectivity.

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Thermoplastic Elastomers Based on Functionalized Polystyrene with Crystallizable Diamide Segment: Synthesis and Characterization
Authors: VAKEES E. , SURESH J. , KAYALVIZHI M. , ARUN A. , KARTHIK S.
Published: August 2015

This article describes the synthesis and characterization of semicrystalline copolymer based on dihydroxy‐terminated polystyrene and a uniform crystallizable diamide (TΦT or T6T) hard segment. The concentration of the diamide in the copolymer varies from 3 to 15 wt% by changing the length of soft segments using dimethylterephthalate as a chain extender. The inherent viscosity of the polymer is very high ranging between 1.6 and 2.9 dL/g. Differential scanning calorimetry spectrum shows Tg for soft and Tm for hard segment as expected for crystalline copolymer. The products are semicrystalline materials with a crystallization window of 3–9°C. Depending on the amide concentration in the copolymer, the hard segments melting temperature ranged between 149 and 275°C. Fourier‐transform infrared spectroscopy (FT‐IR) results show that the degree of crystallinity of the hard segment in the copolymer is very high, that is up to 97%. Temperature‐dependent FT‐IR shows that crystallinity is highly reversible with respect to temperature. Wide angle X‐ray scattering data also confirm that the materials are semicrystalline in nature. The solvent resistivity of these materials is extremely high even at a low concentration of (3%) amide content. The entire polymer shows low water absorption, depending on the concentration of amide segments.
The nature of polymer grafts and substrate shape on the surface degradation of poly(l‐lactide)
Authors: Nugroho Robertus Wahyu N. , Odelius Karin , Höglund Anders , Albertsson Ann‐Christine
Published: August 2015

Surface grafting of functional polymers is an effective method to alter material properties and degradation behavior. Two different substrate shapes of poly(l‐lactide) (PLLA), i.e., films and microparticles, were surface‐grafted with hydrophilic monomers, and their surface degradation was monitored. Surface grafting with a hydrophilic and acidic polymer graft [acrylic acid (AA)] induced large alterations in the surface morphology and topography of the films. In contrast, hydrophilic and neutral polymer grafts [acrylamide (AAm)] had no significant effect on the surface degradation behavior, while the PLLA reference and co‐monomeric (AA/AAm) polymer‐grafted samples exhibited intermediate surface degradation rates. The grafted PAA chains induced a local acidic environment on the surface of the substrates, which in turn catalyzed the surface degradation process. This effect was more pronounced in the films than in the microparticles. Thus, the nature of the grafted chains and substrate geometry were shown to affect the surface degradation behavior of PLLA substrates. © 2015 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 42736.
Synthesis, thermal and mechanical behavior of a silicon/phosphorus containing epoxy resin
Authors: Peng Cong , Wu Zhanjun , Li Jialiang , Wang Zhi , Wang Hongyu , Zhao Ming
Published: August 2015

A liquid silicon/phosphorus containing flame retardant (DOPO–TVS) was synthesized with 9,10‐dihydro‐9‐oxa‐10‐phosphapheanthrene‐10‐oxid (DOPO) and triethoxyvinylsilane (TVS). Meanwhile, a modified epoxy resin (IPTS–EP) was prepared by grafting isocyanate propyl triethoxysilane (IPTS) to the side chain of bisphenol A epoxy resin (EP) through radical polymerization. Finally, the flame retardant (DOPO–TVS) was incorporated into the modified epoxy resin (IPTS–EP) through sol–gel reaction between the ethyoxyl of the two intermediates to obtain the silicon/phosphorus containing epoxy resin. The molecular structures of DOPO–TVS, IPTS–EP and the final modified epoxy resin were confirmed by FTIR spectra and 1H‐NMR, 31P‐NMR. Thermogravimetric analysis (TGA), differential scanning calorimetry, and limiting oxygen index were conducted to explore the thermal properties and flame retardancy of the synthesized epoxy resin. The thermal behavior and flame retardancy were improved. After heating to 600°C in a tube furnace, the char residue of the modified resin containing 10 wt % DOPO–TVS displayed more stable feature compared to that of pure EP, which was observed both by visual inspection and scanning electron microscope (SEM). Moreover, the mechanical performance testing results exhibited the modified epoxy resins possessed elevated tensile properties and fracture toughness which is supported by SEM observation of the tensile fracture section. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42788.
Characterization of light‐cured, dental‐resin‐based biocomposites
Authors: Okulus Zuzanna , Buchwald Tomasz , Voelkel Adam
Published: August 2015

The dependence of the depth of cure (DOC) and degree of conversion (DC) on the depth of experimental and commercial materials were determined according to ISO 4049 procedure and with the use of Raman spectroscopy, respectively. Moreover, an attempt was made to find the correlation between the DOC and DC and the depth of the material. The hypothesis was that curing time recommended by the manufacturers is appropriate for curing both commercial and experimental materials to achieve comparable values of the examined properties. The impact of the filler characteristic was clearly observed. The longer curing time provides a deeper curing (DOC values) and higher reaction rate (DC); however, the dependence between the DC values and DOC values was not visible. Instead, a logarithmic trend in the relation of the DOC and curing time was clearly observed. The results of this study suggest that the experimental materials give some hope for potential clinical applications and should be further investigated. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42812.
Replication dynamics in fission and budding yeasts through DNA polymerase tracking
Authors: Vázquez Enrique , Antequera Francisco
Published: August 2015

The dynamics of eukaryotic DNA polymerases has been difficult to establish because of the difficulty of tracking them along the chromosomes during DNA replication. Recent work has addressed this problem in the yeasts Schizosaccharomyces pombe and Saccharomyces cerevisiae through the engineering of replicative polymerases to render them prone to incorporating ribonucleotides at high rates. Their use as tracers of the passage of each polymerase has provided a picture of unprecedented resolution of the organization of replicons and replication origins in the two yeasts and has uncovered important differences between them. Additional studies have found an overlapping distribution of DNA polymorphisms and the junctions of Okazaki fragments along mononucleosomal DNA. This sequence instability is caused by the premature release of polymerase δ and the retention of non proof‐read DNA tracts replicated by polymerase α. The possible implementation of these new experimental approaches in multicellular organisms opens the door to the analysis of replication dynamics under a broad range of genetic backgrounds and physiological or pathological conditions.
Sensitive determination of glucose in Dulbecco's modified Eagle medium by high‐performance liquid chromatography with 1‐phenyl‐3‐methyl‐5‐pyrazolone derivatization: application to gluconeogenesis studies
Authors: Ling Zhaoli , Xu Ping , Zhong Zeyu , Wang Fan , Shu Nan , Zhang Ji , Tang Xiange , Liu Li , Liu Xiaodong
Published: August 2015

A new pre‐column derivative high‐performance liquid chromatography (HPLC) method for determination of d‐glucose with 3‐O‐methyl‐d‐glucose (3‐OMG) as the internal standard was developed and validated in order to study the gluconeogenesis in HepG2 cells. Samples were derivatized with 1‐phenyl‐3‐methy‐5‐pyrazolone at 70°C for 50 min. Glucose and 3‐OMG were extracted by liquid–liquid extraction and separated on a YMC‐Triart C18 column, with a gradient mobile phase composed of acetonitrile and 20 mm ammonium acetate solution containing 0.09% tri‐ethylamine at a flow rate of 1.0 mL/min. The eluate were detected using a UV detector at 250 nm. The assay was linear over the range 0.39–25 μm (R2 = 0.9997, n = 5) and the lower limit of quantitation was 0.39 μm (0.070 mg/mL). Intra‐ and inter‐day precision and accuracy were <15% and within ±3%, respectively. After validation, the HPLC method was applied to investigate the gluconeogenesis in Dulbecco's modified Eagle medium (DMEM) cultured HepG2 cells. Glucose concentration was determined to be about 1–2.5 μm in this gluconeogenesis assay. In conclusion, this method has been shown to determine small amounts of glucose in DMEM successfully, with lower limit of quantitation and better sensitivity when compared with common commercial glucose assay kits. Copyright © 2015 John Wiley & Sons, Ltd.
Competitive Exclusion Principle in Ecology and Absolute Asymmetric Synthesis in Chemistry
Authors: Ribó Josep M. , Hochberg David
Published: August 2015

The key concepts underlying the Frank model (1953) for spontaneous asymmetric synthesis in chemistry are traced back to the pioneering works of Volterra (1926) and Lotka (1932) on biological species competition. The Lotka‐Volterra (L‐V) two‐species exclusive competition model reduces to the Frank model for the special case of distinguishable but degenerate species (i.e., the enantiomers). The important ecological principle of competitive exclusion, originally derived from the L‐V two‐competitors model, is a consequence of sufficiently antagonistic interactions between the species competing for limited common resources, or mutual inhibition, as the term is known in the chemical literature on absolute asymmetric synthesis. The L‐V and Frank models are described by the same general differential equations, nevertheless a crucial thermodynamic distinction between these models is necessary to correlate ecological selection and chemical selectivity arising from 1) the absence of reversibility in biological transformations, in marked contrast to chemical reactions, and 2) the constraints in chemical scenarios on the reaction rate constants required to fulfill the principle of micro‐reversibility. Chirality 27:722–727, 2015. © 2015 Wiley Periodicals, Inc.
Metamorphic remodeling of the olfactory organ of the African clawed frog, Xenopus laevis
Authors: Dittrich Katarina , Kuttler Josua , Hassenklöver Thomas , Manzini Ivan
Published: August 2015

The amphibian olfactory system undergoes massive remodeling during metamorphosis. The transition from aquatic olfaction in larvae to semiaquatic or airborne olfaction in adults requires anatomical, cellular, and molecular modifications. These changes are particularly pronounced in Pipidae, whose adults have secondarily adapted to an aquatic life style. In the fully aquatic larvae of Xenopus laevis, the main olfactory epithelium specialized for sensing water‐borne odorous substances lines the principal olfactory cavity (PC), whereas a separate olfactory epithelium lies in the vomeronasal organ (VNO). During metamorphosis, the epithelium of the PC is rearranged into the adult “air nose,” whereas a new olfactory epithelium, the adult “water nose,” forms in the emerging middle cavity (MC). Here we performed a stage‐by‐stage investigation of the anatomical changes of the Xenopus olfactory organ during metamorphosis. We quantified cell death in all olfactory epithelia and found massive cell death in the PC and the VNO, suggesting that the majority of larval sensory neurons is replaced during metamorphosis in both sensory epithelia. The moderate cell death in the MC shows that during the formation of this epithelium some cells are sorted out. Our results show that during MC formation some supporting cells, but not sensory neurons, are relocated from the PC to the MC and that they are eventually eliminated during metamorphosis. Together our findings illustrate the structural and cellular changes of the Xenopus olfactory organ during metamorphosis. J. Comp. Neurol. 524:986–998, 2016. © 2015 Wiley Periodicals, Inc.
Recent insights into the morphological diversity in the amniote primary and secondary palates
Authors: Abramyan John , Richman Joy Marion
Published: August 2015

The assembly of the upper jaw is a pivotal moment in the embryonic development of amniotes. The upper jaw forms from the fusion of the maxillary, medial nasal, and lateral nasal prominences, resulting in an intact upper lip/beak and nasal cavities; together called the primary palate. This process of fusion requires a balance of proper facial prominence shape and positioning to avoid craniofacial clefting, whilst still accommodating the vast phenotypic diversity of adult amniotes. As such, variation in craniofacial ontogeny is not tolerated beyond certain bounds. For clarity, we discuss primary palatogenesis of amniotes into in two categories, according to whether the nasal and oral cavities remain connected throughout ontogeny or not. The transient separation of these cavities occurs in mammals and crocodilians, while remaining connected in birds, turtles and squamates. In the latter group, the craniofacial prominences fuse around a persistent choanal groove that connects the nasal and oral cavities. Subsequently, all lineages except for turtles, develop a secondary palate that ultimately completely or partially separates oral and nasal cavities. Here, we review the shared, early developmental events and highlight the points at which development diverges in both primary and secondary palate formation.Developmental Dynamics 244:1457–1468, 2015. © 2015 Wiley Periodicals, Inc.
Sensitive detection of piperazinyl phenothiazine drugs by field‐amplified sample stacking in capillary electrophoresis with dispersive liquid–liquid microextraction
Authors: Tu Yi‐Yi , Hsieh Ming‐Mu , Chang Sarah Y.
Published: August 2015

A rapid, simple and sensitive method for the detection of piperazinyl phenothiazine drugs using dispersive liquid–liquid microextraction (DLLME) combined with field‐amplified sample stacking (FASS) in CE was developed. Sensitivity parameters that affect the extraction and FASS efficiency, such as the type and volume of disperser solvent, extraction time, addition of salt, and efficiency of FASS, were investigated and optimized. Note that the conductivity ratio between BGE and sample zone was measured to be 2300. Under optimal extraction and stacking conditions, the calibration curve, which ranged from 0.3 to 160 ng/mL, demonstrated good linearity with a correlation coefficient r≧ 0.9900. The LODs of prochlorperazine (Pcp), trifluoperazine (Tfp), perphenazine (Ppa), and fluphenazine (Fpa) at an S/N of 3 were 0.1, 0.1, 0.07, and 0.08 ng/mL, respectively. An approximately 1000‐fold to 2500‐fold improvement in sensitivity was achieved for the four tested analytes compared to conventional CZE without DLLME. The recoveries of all phenothiazines in urine and plasma ranged from 85.7 to 107.6% and 95.6 to 105.4%, respectively. The proposed method was demonstrated to be a rapid and convenient method for the determination of four piperazinyl phenothiazine drugs in human urine and plasma.
Getting Off on the Right Foot: The Many Roles of the Psychosocial Evaluation in the Bariatric Surgery Practice
Authors: Sogg Stephanie , Friedman Kelli E.
Published: August 2015

A thorough and specialized pre‐operative psychosocial assessment is an important part of a comprehensive bariatric treatment protocol. Over time, the presurgical psychosocial evaluation has evolved from a cut‐and‐dried process of recommending whether a patient should or should not undergo surgery to a more nuanced and multifaceted process that serves multiple functions. In this article, we review the many ways in which the pre‐operative psychosocial evaluation can enhance patient outcomes and adjustment and even the functioning of the interdisciplinary bariatric surgery team. Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.
Bolus versus continuous infusion of microbubble contrast agent for liver ultrasound by using an automatic power injector in humans: A pilot study
Authors: Quaia Emilio , Gennari Antonio Giulio , Angileri Roberta , Cova Maria Assunta
Published: August 2015

Purpose

To evaluate the feasibility of using continuous infusion, in comparison with bolus injection, of a sulfur hexafluoride–microbubble contrast agent to prolong the duration of hepatic parenchymal enhancement in humans during sonographic examination.

Methods

This pilot study was approved by our institution's ethics committee. Ten patients (5 men and 5 women; mean age ± SD, 65 ± 10 years) each received two injections: a bolus injection (2 ml/s) and then continuous infusion (0.5 ml/min) of the contrast agent by using an automatic injector. Acquired cine clips were transferred to a personal computer, and the video intensity was quantified by dedicated software.

Results

From the time of the first microbubble visualization in the scanning plane, maximal enhancement was reached in 6.3 ± 0.94 seconds after bolus injection and in 13.9 ± 1.44 seconds during continuous infusion (p = 0.002, Wilcoxon's test for paired data). Compared with bolus injection, continuous infusion prolonged the duration of contrast enhancement (4.3 minutes ± 42 seconds versus 7.3 minutes ± 40 seconds; p = 0.002), although no statistically significant difference in maximal enhancement was observed (45 ± 18% for bolus injection and 39 ± 6% for continuous infusion; p = 0.62).

Conclusions

Continuous infusion of sulfur hexafluoride–filled microbubbles via an automatic power injector prolongs hepatic contrast enhancement without significantly modifying the maximal enhancement over that at baseline. These data, coming from a pilot study, can be used to design a larger study with adequate statistical power. © 2015 Wiley Periodicals, Inc. J Clin Ultrasound 44:136–142, 2016
A simple method for selecting spawning‐ready individuals out from laboratorial cultured amphioxus population
Authors: Li Guang , Wang Jing , Yuan Liang , Wang Hui , Wang Yi‐Quan
Published: August 2015

Amphioxus is an emerging model organism for evolutionary developmental (Evo‐Dev) studies owing to its key phylogenetic position in chordates. However, the rare supply of living embryonic materials is a major drawback for using amphioxus as a laboratorial model animal. Although the problem has been partially resolved in several recent reports, the spawning of amphioxus still remains unpredictable to some extent. In the present study, we reported an accurate method to distinguish spawning‐ready and non‐spawning‐ready individuals of amphioxus Branchiostoma belcheri. In comparison with non‐spawning‐ready amphioxus, all spawning‐ready individuals display following features several hours before their spawning: 1) for both males and females, the interstices between two adjacent gonads are obvious and relatively wide; and 2) the connections among eggs are loose and the crannies appear in each individual ovary of females. These morphological features were also observed in B. japonicum, indicating their conservation among different lancelet species. Based on this observable criterion, we made predictions on the spawning of about 600 ripe B. belcheri individuals and acquired an accuracy of 86.7% for females and 80.4% for males. In addition, we found that advancing or delaying onset of darkness has no detectable effect on the timing of spawning of B. belcheri. Our study makes amphioxus spawning more amenable for our experiments and will greatly facilitate its utilization as a laboratorial model animal. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 629–635, 2015. © 2015 Wiley Periodicals, Inc.
Natural estrogens in dairy products: Determination of free and conjugated forms by ultra high performance liquid chromatography with tandem mass spectrometry
Authors: Cavaliere Chiara , Capriotti Anna Laura , Foglia Patrizia , Piovesana Susy , Samperi Roberto , Ventura Salvatore , Laganà Aldo
Published: August 2015

Natural estrogens are synthesized by mammals in different amounts depending on the developmental stage and pregnancy/lactation period, and they may pass into milk, where they are mostly present as glucuronated and sulfated forms. In modern dairy practices, about 75% of milk is produced from pregnant cows; therefore, the amount of hormones that may pass into milk could be of concern. While estrogen determination in milk has been investigated in depth, the individual determination of estrogens and their conjugated forms in dairy products has not been fully addressed. The aim of this work was to develop and assess a sensitive method, using the peculiar retention properties of graphitized carbon black, to extract natural free estrogens and their major conjugated metabolites, without any enzymatic cleavage, from yogurt, cheese, and butter. The free and conjugated estrogens were eluted in two distinct fractions from the solid‐phase extraction cartridge and analyzed separately by ultra high performance liquid chromatography coupled to tandem mass spectrometry. Recoveries were higher than 80% for all the three sample typologies. The highest matrix effects were observed for butter, which was richest in lipid content, but was below 30%. A survey on some commercial dairy products suggests that production processes decreased estrogen content.
Log del Pezzo surfaces with not small fractional indices
Authors: Fujita Kento
Published: August 2015

For a log del Pezzo surfaceS, the fractional indexis the maximum ofrwith whichcan be written asrtimes some Cartier divisor. We classify all the log del Pezzo surfacesSwith, after the technique of Nakayama.
Individualized evaluation of cholinesterase inhibitors effects in dementia with adaptive cognitive testing
Authors: Wouters Hans , Van Campen Jos P.C.M. , Appels Bregje A. , Beijnen Jos H. , Zwinderman Aeilko H. , Van Gool Willem A. , Schmand Ben
Published: August 2015

Computerized Adaptive Testing (CAT) of cognitive function, selects for every individual patient, only items of appropriate difficulty to estimate his or her level of cognitive impairment. Therefore, CAT has the potential to combine brevity with precision. We retrospectively examined the evaluation of treatment effects of cholinesterase inhibitors by CAT using longitudinal data from 643 patients from a Dutch teaching hospital who were diagnosed with Alzheimer disease or Lewy Body disease. The Cambridge Cognitive Examination (CAMCOG) was administered before treatment initiation and after intervals of six months of treatment. A previously validated CAT was simulated using 47 CAMCOG items. Results demonstrated that the CAT required a median number of 17 items (inter‐quartile range 16–20), or a corresponding 64% test reduction, to estimate patients’ global cognitive impairment levels. At the same time, intraclass correlations between global cognitive impairment levels as estimated by CAT or based on all 47 CAMCOG items, ranged from 0.93 at baseline to 0.91–0.94 at follow‐up measurements. Slightly more people had substantial decline on the original CAMCOG (N = 31/285, 11%) than on the CAT (N = 17/285, 6%). We conclude that CAT saves time, does not lose much precision, and therefore deserves a role in the evaluation of treatment effects in dementia. Copyright © 2015 John Wiley & Sons, Ltd.
Prospective acceleration of diffusion tensor imaging with compressed sensing using adaptive dictionaries
Authors: McClymont Darryl , Teh Irvin , Whittington Hannah J. , Grau Vicente , Schneider Jürgen E.
Published: August 2015

Purpose

Diffusion MRI requires acquisition of multiple diffusion‐weighted images, resulting in long scan times. Here, we investigate combining compressed sensing and a fast imaging sequence to dramatically reduce acquisition times in cardiac diffusion MRI.

Methods

Fully sampled and prospectively undersampled diffusion tensor imaging data were acquired in five rat hearts at acceleration factors of between two and six using a fast spin echo (FSE) sequence. Images were reconstructed using a compressed sensing framework, enforcing sparsity by means of decomposition by adaptive dictionaries. A tensor was fit to the reconstructed images and fiber tractography was performed.

Results

Acceleration factors of up to six were achieved, with a modest increase in root mean square error of mean apparent diffusion coefficient (ADC), fractional anisotropy (FA), and helix angle. At an acceleration factor of six, mean values of ADC and FA were within 2.5% and 5% of the ground truth, respectively. Marginal differences were observed in the fiber tracts.

Conclusion

We developed a new k‐space sampling strategy for acquiring prospectively undersampled diffusion‐weighted data, and validated a novel compressed sensing reconstruction algorithm based on adaptive dictionaries. The k‐space undersampling and FSE acquisition each reduced acquisition times by up to 6× and 8×, respectively, as compared to fully sampled spin echo imaging. Magn Reson Med 76:248–258, 2016. © 2015 Wiley Periodicals, Inc.
Preparation, structural characterization, and antioxidative behavior in natural rubber of antioxidant GM functionalized nanosilica
Authors: Li Hongqiang , Liang Tao , Li Feng , Wu Wenjian , Lai Xuejun , Guo Jianhua , Zeng Xingrong
Published: August 2015

To restrain the migration and extractability of the antioxidants and improve the dispersion of nanosilica in natural rubber (NR), antioxidant 2‐tert‐butyl‐6‐(3‐tert‐butyl‐2‐hydroxy‐5‐methylbenzyl)‐4‐methyphenyl acrylate (GM) functionalized nanosilica was prepared using antioxidant coupling agent (KH590‐GM) as functional modifier, which was first synthesized through thiol‐ene reaction between the mercapto group of γ‐mercaptopropyl trimethoxysilane (KH590) and the CC double bonds of antioxidant GM. Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance confirmed the structure of KH590‐GM and GM functionalized nanosilica. Thermogravimetry analysis indicated that the grafting rate of GM functionalized nanosilica reached 13.4%, and the antioxidant had good thermal stability. Scanning electron microscope and mechanical properties measurement showed GM functionalized nanosilica was dispersed uniformly in NR vulcanizates, and helpful for the increase of the tensile strength and tensile stress of NR vulcanizates. Based on the study of the antioxidative behavior and extraction resistance of the NR vulcanizates, it was found that in contrast to NR vulcanizates with GM, the ageing coefficient and oxidation induction time of that with GM functionalized nanosilica increased to 0.66 and 39 min from 0.58 and 30 min, respectively. Furthermore, the NR vulcanizates with GM functionalized nanosilica also exhibited excellent extraction resistance. POLYM. COMPOS., 38:1241–1247, 2017. © 2015 Society of Plastics Engineers
Free energy landscape of a minimalist salt bridge model
Authors: Li Xubin , Lv Chao , Corbett Karen M. , Zheng Lianqing , Wu Dongsheng , Yang Wei
Published: August 2015

Salt bridges are essential to protein stability and dynamics. Despite the importance, there has been scarce of detailed discussion on how salt bridge partners interact with each other in distinct solvent exposed environments. In this study, employing a recent generalized orthogonal space tempering (gOST) method, we enabled efficient molecular dynamics simulation of repetitive breaking and reforming of salt bridge structures within a minimalist salt‐bridge model, the Asp‐Arg dipeptide and thereby were able to map its detailed free energy landscape in aqueous solution. Free energy surface analysis shows that although individually‐solvated states are more favorable, salt‐bridge states still occupy a noticeable portion of the overall population. Notably, the competing forces, e.g. intercharge attractions that drive the formation of salt bridges and solvation forces that pull the charged groups away from each other, are energetically comparable. As the result, the salt bridge stability is highly tunable by local environments; for instance when local water molecules are perturbed to interact more strongly with each other, the population of the salt‐bridge states is likely to increase. Our results reveal the critical role of local solvent structures in modulating salt‐bridge partner interactions and imply the importance of water fluctuations on conformational dynamics that involves solvent accessible salt bridge formations.
Filtration system performance cleaning exhaust air of pneumatic maize seed drills
Authors: Manzone Marco , Tamagnone Mario
Published: August 2015

BACKGROUND

In the agricultural sector, toxic substances can be released into the atmosphere. In recent years, Europe has encountered a significant environmental issue related to the dispersion of pesticides during maize seeding, especially when performed with pneumatic seed drills. This phenomenon can be very dangerous for insects, as the dispersed dust contains pesticides (insecticides, fungicides, etc.) used to dress maize seeds. On the basis of these considerations, experimental tests have been carried out using a filtration system to clean the airflow that exits from the fan of pneumatic maize seed drills.

RESULTS

The tested filtration system does not interfere with the seeding quality because the vacuum level observed within the filtration system assembled on the seeder (5.7 kPa) is 27% higher than the correct vacuum level to guarantee good seeding quality (4.2 kPa). In addition, it enables a reduction in the risk of environmental contamination, as no dust deposits were found at different distances from the machine.

CONCLUSION

The use of a filtration system shows advantages in terms of environmental and operator safety because dangerous materials are contained in the filter case, thus avoiding contamination of neighbouring areas and the machinery used (tractor and seed drill). © 2015 Society of Chemical Industry