bluuebunny/crossref_metadata_2025 huggingface dataset:
Flow instabilities of time‐dependent injection schemes in immiscible displacements
Authors: Lins Tiago F. , Azaiez Jalel
Published: July 2016

Flow displacements in homogeneous porous media can result in instabilities at the interface between the fluids. Such instabilities may dramatically affect the overall efficiency of the displacement process and often need to be controlled. Flows that involve time‐dependent injection schemes are analyzed to determine their effects on the growth of instabilities and the nonlinear development of finger structures in immiscible displacements. Predictions for monotonic and cyclic schemes in radial displacements are presented and compared with their constant injection counterpart. Moreover a controlled injection scheme that allows minimizing the instabilities is proposed. A hybrid model accounting for the discontinuities across the interface is implemented, and the problem is solved numerically. The effects of different parameters including the phase shift, amplitude, and period as well as the role of the mobility ratio and surface tension are discussed. A set of injection policies are observed to lead to the strongest attenuation of instabilities. Moreover, optimal phase shifts for cyclic displacements can result in the strongest enhancement or attenuation of the instability, depending on whether the flow involves extraction. A novel approach, referred to as the controlled injection scheme, has also been proposed and analyzed. In this scheme the flow is continuously adjusted in response to the growth rate of the instabilities resulting in a better capability of suppressing the development and growth of fingers.
Experimental Investigation on Abstraction of Phenol Onto Micrococcus lylae and Cetyl Trimethyl Ammonium Bromide
Authors: Saravani Natarajan , Arulmozhi Muthukumarasamy , Vaidhegi Kugarajah
Published: July 2016

Air floatation, an efficient solid–liquid separation process, was tested as a post treatment technique for phenol removal. The results consider about the practical solutions for certain operations such as efficient solid–liquid separation, attainment of maximized percentage removal, phenol rich solution with Micrococcus lylae cells, and pure water without M. lylae cells. The two processes, biosorption and flotation, can effectively operate in combination and both the sorbent and treated water can be recycled. The effect of various operating parameters, such as initial feed concentration, equilibrium time, biosorbent dose, pH, liquid pool height, surfactant concentration, and air flow rate, was experimentally investigated. The maximum sorption capacity was found to be 303 mg/g at pH 7 and an initial phenol concentration of 500 mg/L. The higher floatability of M. lylae was obtained in a maximum time of 10 min. In addition, the adsorption isotherm and kinetic studies revealed that the biosorption process followed the Dubinin–Radushkevich model (R2 = 0.982) and pseudo‐first order kinetics with a kinetic constant of 2.6537/day. The adsorbed chemical species was identified by Fourier transform infrared (FTIR) spectroscopy. Electrokinetic measurements were carried out to determine the isoelectric point of the bacteria. The zeta potential profile of the bacteria was affected by the presence of phenol at different pH values. The recovery of phenol loaded biomass and final traces of phenol by flotation were found to be 99.91%.
Correction of B0 Drift Effects in Magnetic Resonance Thermometry using Magnetic Field Monitoring Technique
Authors: Hernandez Daniel , Kim Ki Soo , Michel Eric , Lee Soo Yeol
Published: July 2016

When magnetic resonance (MR) thermometry is performed for temperature monitoring during time‐consuming thermal therapy like hyperthermia, tiny main magnetic field (B0) drifts may cause significant errors in temperature readings inside the human subject. We propose a correction method of B0 drift effects in MR thermometry, which is based on temperature‐dependent proton resonance frequency shift (PRFS) of water molecules. We placed magnetic field monitoring (MFM) probes around the subject and we read the center frequency of MFM signals. By interpolating the center frequencies of MFM signals on the imaging slice, we computed phase correction maps for MR thermometry. We intermittently acquired MFM signals with performing MR thermometry at 3 Tesla during radiofrequency (RF) heating of a tissue‐mimicking phantom. With the B0 drift effect correction, the temperature readings of MR thermometry maps became similar to the temperature readings of an optic fiber temperature sensor embedded at the center of the phantom. We believe the proposed correction method can be used for MRI‐guided thermal therapy in which precise temperature monitoring is critical.
The effect of referral for genetic counseling on genetic testing and surgical prevention in women at high risk for ovarian cancer: Results from a randomized controlled trial
Authors: Drescher Charles W. , Beatty J. David , Resta Robert , Andersen M. Robyn , Watabayashi Kate , Thorpe Jason , Hawley Sarah , Purkey Hannah , Chubak Jessica , Hanson Nancy , Buist Diana S. M. , Urban Nicole
Published: July 2016

BACKGROUND

Guidelines recommend genetic counseling and testing for women who have a pedigree suggestive of an inherited susceptibility for ovarian cancer. The authors evaluated the effect of referral to genetic counseling on genetic testing and prophylactic oophorectomy in a randomized controlled trial.

METHODS

Data from an electronic mammography reporting system identified 12,919 women with a pedigree that included breast cancer, of whom 625 were identified who had a high risk for inherited susceptibility to ovarian cancer using a risk‐assessment questionnaire. Of these, 458 women provided informed consent and were randomized 1:1 to intervention consisting of a genetic counseling referral (n = 228) or standard clinical care (n = 230).

RESULTS

Participants were predominantly aged 45 to 65 years, and 30% and 20% reported a personal history of breast cancer or a family history of ovarian cancer, respectively. Eighty‐five percent of women in the intervention group participated in a genetic counseling session. Genetic testing was reported by 74 (33%) and 20 (9%) women in the intervention and control arms (P < .005), respectively. Five women in the intervention arm and 2 in the control arm were identified as germline mutation carriers. Ten women in the intervention arm and 3 in the control arm underwent prophylactic bilateral salpingo‐oophorectomy (P < .05).

CONCLUSIONS

Routine referral of women at high risk for ovarian cancer to genetic counseling promotes genetic testing and prophylactic surgery. The findings from the current randomized controlled trial demonstrate the value of implementing strategies that target women at high risk for ovarian cancer to ensure they are offered access to recommended care. CA Cancer J Clin 2016. © 2016 American Cancer Society, Inc. Cancer 2016;122:3509–3518. © 2016 American Cancer Society
Liver and Kidney on Chips: Microphysiological Models to Understand Transporter Function
Authors: Chang SY , Weber EJ , Ness KP Van , Eaton DL , Kelly EJ
Published: July 2016

Because of complex cellular microenvironments of both the liver and kidneys, accurate modeling of transport function has remained a challenge, leaving a dire need for models that can faithfully recapitulate both the architecture and cell‐cell interactions observed in vivo. The study of hepatic and renal transport function is a fundamental component of understanding the metabolic fate of drugs and xenobiotics; however, there are few in vitro systems conducive for these types of studies. For both the hepatic and renal systems, we provide an overview of the location and function of the most significant phase I/II/III (transporter) of enzymes, and then review current in vitro systems for the suitability of a transporter function study and provide details on microphysiological systems that lead the field in these investigations. Microphysiological modeling of the liver and kidneys using “organ‐on‐a‐chip” technologies is rapidly advancing in transport function assessment and has emerged as a promising method to evaluate drug and xenobiotic metabolism. Future directions for the field are also discussed along with technical challenges encountered in complex multiple‐organs‐on‐chips development.
Influence of low direct electric currents and chlorhexidine upon human dental biofilms
Authors: Lasserre Jérôme F. , Toma Selena , Bourgeois Thomas , El Khatmaoui Hajar , Marichal Estelle , Brecx Michel C.
Published: July 2016

Dental biofilms have been widely associated with biological complications of oral implants. Currently, no consensus exists regarding the most reliable anti‐infective approach to treat peri‐implantitis. This study aimed to investigate whether low direct electric currents (DC) could influence chlorhexidine (CHX) 0.2% antimicrobial efficacy against human dental biofilms. To support biofilm accumulation, discs made with machined titanium (Ti) or hydroxyapatite (HA) were used. Five volunteers wore during 24 h an intraoral thermoformed splint on which ten specimens were bonded. Biofilms were then collected and treated ex vivo. During each antimicrobial experiment (N = 20 replicates), two modalities of treatment (CHX/PBS = control groups and CHX/PBS+5mA = test groups) were tested (n = 5 discs each) and the number of viable bacteria evaluated in LogCFU/mL at baseline, 0.5, 1, 2 and 5 min. The proportion of killed bacteria was also estimated and compared statistically at each time point between control and test groups. CHX+/−5mA induced a mean viability reduction around 90–95% after 5 min of treatment whatever the surface considered (Ti/HA). A significant difference regarding the bactericidal effect was noted on Ti surfaces after 0.5, 1 and 2 min in favor of the CHX+5mA modality when compared to CHX alone (p < 0.05). PBS+5mA also had a certain antimicrobial effect (58%) after 5 min on Ti surfaces. This effect was significantly higher than that observed with PBS (25%) (p < 0.05). This study showed that low DC (5mA) can have an antibiofilm effect and are also able to enhance chlorhexidine 0.2% efficacy against human dental biofilms grown on titanium surfaces.
Across the Board: Michael North
Authors: North Michael
Published: July 2016

In this series of articles, the board members of ChemSusChem discuss recent research articles that they consider of exceptional quality and importance for sustainability. This entry features Prof. Michael North, who discusses the main points and challenges towards sustainable ring‐opening polymerisation methods, stressing that the overall reaction conditions, as well as highly active polymerisation initiators based on Earth abundant materials, must be considered and optimized.
Effects of pointing errors and channel fading on the performance of free‐space optically‐preamplified PPM systems
Authors: Landolsi Taha , Elrefaie Aly F.
Published: July 2016

In this paper, we study the impact of pointing errors and channel fading on the performance of free‐space, optically preamplified, M‐ary PPM systems. We consider two types of free‐space optical links: (i) inter‐satellite links and (ii) inter‐building links. For inter‐satellite links, only pointing error is considered. Starting with a Rayleigh model for the pointing error angle, we derive analytically the PDF for the pointing error parameter and for the signal‐to‐noise ratio (SNR) per bit. For inter‐building links, we derive the density function for the SNR per bit that includes the combined effects of pointing errors and channel fading, assuming Rayleigh‐distributed pointing errors. The channel fading models considered in this study for inter‐buildings links are the log‐normal and gamma–gamma models. We provide the error probability as a function of the average SNR per bit for both types of links. To cover systems with and without forward error correction, we compute the average SNR per bit required to achieve a bit error rate of 10−4 and 10−9. The corresponding power penalties are computed for different symbol sizes, scintillation indexes, and pointing jitters. Copyright © 2016 John Wiley & Sons, Ltd.
Tools to evaluate pharmacokinetics data for establishing maximum residue limits for approved veterinary drugs: examples from JECFA's work
Authors: Sanders P. , Henri J. , Laurentie M.
Published: July 2016

Maximum residue limits (MRLs) for residues of veterinary drugs are the maximum concentrations of residues permitted in or on a food by national or regional legislation. In the process of MRLs recommendations by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), analysis of pharmacokinetic data describing the ADME process (absorption, distribution, metabolism and excretion) is a crucial step and requires the use of different pharmacokinetic tools. The results of animal metabolism studies are the prime determinants of the residue definition in food commodities. Substances labelled with radioactive isotopes are used so that the disposition of the residue can be followed as total residue and main metabolites concentrations. Residue depletion studies with radiolabelled parent drug will lead to the estimate of the time course of the total residue and to determine a marker residue. Depletion studies with an unlabelled drug provide more information on the time course of the marker residue in raw commodities after administration under approved practical conditions of use. By use of this information and after conversion with the total/residue marker ratio, MRLs are derived by comparison of the acceptable daily intake with the daily intakes calculated with different scenarios of dietary exposure. Progress in pharmacokinetic model such as physiologically based pharmacokinetics and population pharmacokinetics will drive the future research in this field to improved veterinary drug development. Copyright © 2016 John Wiley & Sons, Ltd.
GLP principles and their role in supporting pharmacokinetic and residue depletion studies for drug registration and licensing
Authors: Croubels Siska , De Backer Patrick , Devreese Mathias
Published: July 2016

Good Laboratory Practice (GLP) is a quality system concerned with the organizational process and the conditions under which non‐clinical health and environmental safety studies are planned, performed, monitored, recorded, archived, and reported. This paper focuses on the GLP principles applicable for veterinary drug registration and licensing purposes. First, a general overview of the GLP requirements is given, followed by a more specific comparison and discussion of the analytical method validation parameters and acceptance criteria of different international guidelines applied in the context of veterinary drug pharmacokinetic and residue depletion studies. Finally, some needs with respect to method validation and new developments in pharmacokinetic and residue depletion studies are highlighted. Copyright © 2016 John Wiley & Sons, Ltd.
Emerging food safety issues: An EU perspective
Authors: McEvoy John D. G.
Published: July 2016

Safe food is the right of every citizen of the European Union (EU). A comprehensive and dynamic framework of food and feed safety legislation has been put in place and the EU's executive arm – the European Commission – is responsible for ensuring that the EU member states apply food law consistently. Similarly, the Commission plays an important role in ensuring that imported food meets the EU's stringent food safety standards. Consumer perceptions of unsafe food tend to focus on acute outbreaks of bacterial or viral origin. In recent years there have been a number of diverse food crises associated with fraudulent activity which may (e.g. melamine in dairy products in China) or may not (e.g. the horse meat scandal in the EU) represent a genuine food safety risk. Well publicized incidents of chronic exposure to chemical contamination in the EU (e.g. dioxins in meat and mycotoxins in nuts) have required robust coordinated policy responses from the Commission. Despite the decreasing incidence of non‐compliant residues of veterinary medicinal products and banned substances in animal products, EU consumers are increasingly concerned about the use of such products in food‐producing animals, including in the context of the build‐up of antimicrobial resistance in animals and transfer to humans. The Commission plays a key role in coordination of the EU member states' responses to such incidents, in risk management, and in preparation for emerging issues. This paper focuses on how the EU as a whole has dealt with a number of food crises, and what can be learned from past incidents. Copyright © 2016 John Wiley & Sons, Ltd.
A single laboratory‐validated LC‐MS method for the analysis of tulathromycin residues in bison and deer sera and selected tissues of white‐tailed deer
Authors: Boison Joe O. , Bachtold Kali , Matus Johanna , Alcorn Jane , Woodbury Murray
Published: July 2016

The performance characteristics of a newly developed liquid chromatography‐mass spectrometry (LC‐MS) method were validated and demonstrated to be fit for purpose in a pharmacokinetic and tissue depletion study of white‐tailed deer and bison. Tulathromycin was extracted from bison and deer sera with acetonitrile or trifluoroacetic acid and K2HPO4 (pH 6.8) buffer solution and cleaned up on a conditioned Bond‐Elut cartridge. Tulathromycin, retained on the cartridge; it was eluted with methanol containing 2% formic acid, dried, re‐constituted in methanol/1% formic acid, and analyzed by LC‐MS. The limit of quantification (LOQ) of the method was 0.6 ng/mL in serum and 0.6 ng/g in tissue with RSDs ≤ 10% and accurate over the linear calibration range of 0.8–100 ng/mL for bison serum, 0.6–50 ng/mL for deer serum, 100–2500 ng/g for deer muscle tissue, and 500–5000 ng/g for deer lung tissue, all with coefficients of determination, r2≥0.99. The validated method was used to quantify the concentration of tulathromycin residues in serum of bison and deer and selected tissue (lung and muscle tissue) samples obtained from 10 healthy, white‐tailed deer that were administered the therapeutic dose approved for cattle (i.e., a single 2.5 mg/kg subcutaneous injection of tulathromycin in the neck). The deer were included in a tulathromycin drug depletion study. © 2016 Her Majesty the Queen in Right of Canada. Drug Testing and Analysis © 2016 John Wiley & Sons, Ltd.
High throughput‐screening of animal urine samples: It is fast but is it also reliable?
Authors: Kaufmann Anton
Published: July 2016

Advanced analytical technologies like ultra‐high‐performance liquid chromatography coupled to high resolution mass spectrometry can be used for veterinary drug screening of animal urine. The technique is sufficiently robust and reliable to detect veterinary drugs in urine samples of animals where the maximum residue limit of these compounds in organs like muscle, kidney, or liver has been exceeded. The limitations and possibilities of the technique are discussed. The most critical point is the variability of the drug concentration ratio between the tissue and urine. Ways to manage the false positive and false negatives are discussed. The capability to confirm findings and the possibility of semi‐targeted analysis are also addressed. Copyright © 2016 John Wiley & Sons, Ltd.
Examining variation in the leaf mass per area of dominant species across two contrasting tropical gradients in light of community assembly
Authors: Neyret Margot , Bentley Lisa Patrick , Oliveras Imma , Marimon Beatriz S. , Marimon‐Junior Ben Hur , Almeida de Oliveira Edmar , Barbosa Passos Fábio , Castro Ccoscco Rosa , dos Santos Josias , Matias Reis Simone , Morandi Paulo S. , Rayme Paucar Gloria , Robles Cáceres Arturo , Valdez Tejeira Yolvi , Yllanes Choque Yovana , Salinas Norma , Shenkin Alexander , Asner Gregory P. , Díaz Sandra , Enquist Brian J. , Malhi Yadvinder
Published: July 2016

Understanding variation in key functional traits across gradients in high diversity systems and the ecology of community changes along gradients in these systems is crucial in light of conservation and climate change. We examined inter‐ and intraspecific variation in leaf mass per area (LMA) of sun and shade leaves along a 3330‐m elevation gradient in Peru, and in sun leaves across a forest–savanna vegetation gradient in Brazil. We also compared LMA variance ratios (T‐statistics metrics) to null models to explore internal (i.e., abiotic) and environmental filtering on community structure along the gradients. Community‐weighted LMA increased with decreasing forest cover in Brazil, likely due to increased light availability and water stress, and increased with elevation in Peru, consistent with the leaf economic spectrum strategy expected in colder, less productive environments. A very high species turnover was observed along both environmental gradients, and consequently, the first source of variation in LMA was species turnover. Variation in LMA at the genus or family levels was greater in Peru than in Brazil. Using dominant trees to examine possible filters on community assembly, we found that in Brazil, internal filtering was strongest in the forest, while environmental filtering was observed in the dry savanna. In Peru, internal filtering was observed along 80% of the gradient, perhaps due to variation in taxa or interspecific competition. Environmental filtering was observed at cloud zone edges and in lowlands, possibly due to water and nutrient availability, respectively. These results related to variation in LMA indicate that biodiversity in species rich tropical assemblages may be structured by differential niche‐based processes. In the future, specific mechanisms generating these patterns of variation in leaf functional traits across tropical environmental gradients should be explored.
Limited spatial response to direct predation risk by African herbivores following predator reintroduction
Authors: Davies Andrew B. , Tambling Craig J. , Kerley Graham I.H. , Asner Gregory P.
Published: July 2016

Predators affect ecosystems not only through direct mortality of prey, but also through risk effects on prey behavior, which can exert strong influences on ecosystem function and prey fitness. However, how functionally different prey species respond to predation risk and how prey strategies vary across ecosystems and in response to predator reintroduction are poorly understood. We investigated the spatial distributions of six African herbivores varying in foraging strategy and body size in response to environmental factors and direct predation risk by recently reintroduced lions in the thicket biome of the Addo Elephant National Park, South Africa, using camera trap surveys, GPS telemetry, kill site locations and Light Detection and Ranging. Spatial distributions of all species, apart from buffalo, were driven primarily by environmental factors, with limited responses to direct predation risk. Responses to predation risk were instead indirect, with species distributions driven by environmental factors, and diel patterns being particularly pronounced. Grazers were more responsive to the measured variables than browsers, with more observations in open areas. Terrain ruggedness was a stronger predictor of browser distributions than was vegetation density. Buffalo was the only species to respond to predator encounter risk, avoiding areas with higher lion utilization. Buffalo therefore behaved in similar ways to when lions were absent from the study area. Our results suggest that direct predation risk effects are relatively weak when predator densities are low and the time since reintroduction is short and emphasize the need for robust, long‐term monitoring of predator reintroductions to place such events in the broader context of predation risk effects.
Introducing BioSARN – an ecological niche model refinement tool
Authors: Heap Marshall J.
Published: July 2016

Environmental niche modeling outputs a biological species' potential distribution. Further work is needed to arrive at a species' realized distribution. The Biological Species Approximate Realized Niche (BioSARN) application provides the ecological modeler with a toolset to refine Environmental niche models (ENMs). These tools include soil and land class filtering, niche area quantification and novelties like enhanced temporal corridor definition, and output to a high spatial resolution land class model. BioSARN is exemplified with a study on Fraser fir, a tree species with strong land class and edaphic correlations. Soil and land class filtering caused the potential distribution area to decline 17%. Enhanced temporal corridor definition permitted distinction of current, continuing, and future niches, and thus niche change and movement. Tile quantification analysis provided further corroboration of these trends. BioSARN does not substitute other established ENM methods. Rather, it allows the experimenter to work with their preferred ENM, refining it using their knowledge and experience. Output from lower spatial resolution ENMs to a high spatial resolution land class model is a pseudo high‐resolution result. Still, it maybe the best that can be achieved until wide range high spatial resolution environmental data and accurate high precision species occurrence data become generally available.
Evolution of opercle bone shape along a macrohabitat gradient: species identification using mtDNAand geometric morphometric analyses in neotropical sea catfishes (Ariidae)
Authors: Stange Madlen , Aguirre‐Fernández Gabriel , Cooke Richard G. , Barros Tito , Salzburger Walter , Sánchez‐Villagra Marcelo R.
Published: July 2016

Transitions between the marine and freshwater macrohabitat have occurred repeatedly in the evolution of teleost fishes. For example, ariid catfishes have moved from freshwater to marine environments, and vice versa. Opercles, a skeletal feature that has been shown to change during such transitions, were subjected to 2D geometric morphometric analyses in order to investigate evolutionary shape changes during habitat transition in ariid catfishes and to test the influence of habitat on shape changes. A mtDNAmarker, which proved useful in previous studies, was used to verify species identities. It greatly improved the assignment of specimens to a species, which are difficult to assign by morphology alone. The application of a mtDNAmarker confirmed the occurrence ofNotarius biffiin Central America, South of El Salvador. Molecular identification together with principal component analysis (PCA) and further morphological inspection of neurocrania indicated the existence of a cryptic species withinBagre pinnimaculatus. Principal component (PC) scores of individual specimens clustered in morphospace by genus rather than by habitat. Strong phylogenetic structure was detected using a permutation test ofPCscores of species means on a phylogenetic tree. Calculation of Pagel'sλsuggested that opercle shape evolved according to a Brownian model of evolution. Yet canonical variate analysis (CVA) conducted on the habitat groups showed significant differences in opercle shapes among freshwater and marine species. Overall, opercle shape in tropical American Ariidae appears to be phylogenetically constrained. This verifies the application of opercle shape as a taxonomic tool for species identification in fossil ariid catfishes. At the same time, adaptation to freshwater habitats shows characteristic opercle shape trajectories in ariid catfishes, which might be used to detect habitat preferences in fossils.
Influence of droughts on Nothofagus pumilio forest decline across northern Patagonia, Argentina
Authors: Rodríguez‐Catón Milagros , Villalba Ricardo , Morales Mariano , Srur Ana
Published: July 2016

Understanding the influence of climatic variations on forest decline is a major challenge for scientists investigating global changes. Although reductions in tree growth have previously been associated with forest decline, comprehensive efforts to understand these relationships are rare. Based on ring‐width variations, we determine the influence of climatic fluctuations on the onset and temporal evolution of Nothofagus pumilio forest decline in the Patagonian Andes. Basal area increment (BAI) data from 294 Nothofagus trees at 11 stands in a 500‐km latitudinal transect along the forest–steppe ecotone were used to identify the dominant patterns of regional growth. Three Regional dominant patterns, showing common variations in BAI, were derived. Two BAI patterns show high rates of growth from early to mid‐20th century, followed by sustained negative trends over the last 3–6 decades, whereas the third pattern is characterized by a positive trend since the 1960s. Tipping points in growth trends of the first two patterns are associated with two extreme dry–warm climate events in spring–summer of 1942–1943/1943–1944/1944–1945 and 1978–1979. Both severe droughts were preceded by up to 10 yr of wet periods that promoted above‐average tree growth. We concluded that severe droughts occurring after wet periods trigger the decline of large, dominant N. pumilio trees with high rates of growth. The coincidence between major changes in regional growth with two of the most severe droughts in the instrumental records shows that climatic variations over northern Patagonia synchronize the beginning of forest decline at a regional scale. As these dry–mesic N. pumilio sites will face more severe droughts in the 21st century, as suggested by future climate scenarios, the areas affected by forest decline would increase substantially.
Polyphagy on unpredictable resources does not exclude host specialization: insects feeding on mushrooms
Authors: Põldmaa Kadri , Kaasik Ants , Tammaru Toomas , Kurina Olavi , Jürgenstein Siiri , Teder Tiit
Published: July 2016

The degree of ecological specialization plays a crucial role in shaping the structure and functioning of communities. However, comparing specialization within and among groups of organisms is complicated by both methodological issues and conceptual and terminological inconsistencies. Environmental predictability has been considered a key determinant of specialization though empirical evidence is still limited. Fungi and their insect consumers provide a poorly studied but promising system to measure host specialization and test the predictability hypothesis. In this study, we systematically sampled mushrooms in North European boreal forest, and reared total samples of fungivores colonizing the fruitbodies. Due to the unpredictable nature of mushrooms as a resource, low levels of host specialization can be predicted for these insects, which have indeed widely been considered polyphagous. Contrary to expectations, the majority of the studied fungus gnats were found not to exploit their host taxa indiscriminately. Not only were some mushroom taxa never colonized, the infestation rate of acceptable hosts also differed in most of these fungivores. Gnat species themselves formed continua with respect to the estimates of the degree of specialization, derived from parametric individual‐based analyses of presence‐absence data. In most cases, host use was best explained by models in which the hosts were classified at genus level, with limited support to specialization to particular host species, families, or orders. Indeed, most of the common fungivores appeared to preferentially use various species from one or a few mushroom genera while occasionally feeding on members of other host taxa. This pattern has likely evolved as a compromise between selective forces stemming from host unpredictability and taxon‐specific chemical profiles of the mushrooms. Our study highlights the multidimensional nature of ecological specialization: a high number of acceptable hosts does not preclude considerable discrimination among members of the available resource pool. Such situations can only be revealed by individual‐based analyses capable of capturing differences in partner‐to‐partner interaction intensities.
Design of Suboptimal Weight Using Frequency Responses Guaranteeing Performance Level of Controller for H∞ Loop Shaping Method
Authors: KUBO TAKAYUKI , YUBAI KAZUHIRO , YASHIRO DAISUKE , HIRAI JUNJI
Published: July 2016

The H∞ loop shaping method is known as one of the robust controller design methods. In this method, the design procedure consists of two steps: the weight design and the derivation of a controller. The controller is derived for the weighted plant to suppress the H∞ norm of the transfer matrix consisting of a sensitivity function, a complementary sensitivity function, and so on. Therefore, the closed‐loop system achieves good tracking and robustness. However, there is only a guideline for the weight design, and an explicit design index of the weight has not been given. As a result, a time‐consuming and tedious process is often required to tune the weight. This paper provides a new weight design method for a stable single‐input single‐output (SISO) plant. The resulting weight guarantees the upper bound of the performance level before the controller design. This means that the controller design and the weight design are completely separated in contrast to the Lanzon's work. Moreover, the weight is designed using only frequency responses. Accordingly, we can avoid the process of the system identification and reduce the conservativeness caused by an overestimate of the system uncertainty.
Dielectric Recovery Characteristics after High‐Frequency Current Interruption in Vacuum Circuit Breaker
Authors: TAMAKI SATORU , GANAHA KAZUKI , OSHIRO RYOJI , KANEKO EIJI
Published: July 2016

When the contacts of circuit breaker are opened just before current zero, the gap between contacts will still be very short. Therefore, it cannot withstand recovery voltage between the contacts. In such a case, multiple reignition is likely to take place. Many investigators had tried to clarify this phenomenon, and many reports have been published. However, high‐frequency current interruption and dielectric recovery characteristics are related to some parameters (value of current, arc time, and so on). In addition, arc phenomenon has also been implicated. Hence, it is difficult to understand this phenomenon accurately. In this paper, we conducted dielectric recovery test and high‐frequency current interruption test. Further, we conducted observation experiment using vacuum chamber in order to investigate the effect of small dc current. At the end, we calculated plasma density in the electrodes after high‐frequency current interruption by considering the result of observation experiment and dielectric recovery test.
Luminescent Carbonyl Hydrido Ruthenium(II) Diimine Coordination Compounds: Structural, Photophysical, and Electrochemical Properties
Authors: Yu Fei , Chu Wing‐Kin , Shen Chang , Luo Ya , Xiang Jing , Chen Shu‐Qi , Ko Chi‐Chiu , Lau Tai‐Chu
Published: July 2016

A series of luminescent carbonyl hydrido ruthenium(II) complexes with various diimine ligands with diverse electronic properties, including Me2bpy (bpy = bipyridine), Me2phen (phen = phenanthroline), PhenCOOH, PhenCN, Me2Ph2phen, Ph2phen, and π‐conjugating dipyrido[3,2‐d:2′,3′‐f]quinoxaline (dpq), dipyrido[3,2‐a:2′,3′‐c](6,7,8,9‐tetrahydro)phenazine (dpqc), and dipyridophenazine (dppz) have been synthesized and characterized. Four of these complexes have been structurally characterized by X‐ray crystallography. The photophysical and electrochemical properties of these complexes have been studied. The effects of the electronic features and π‐conjugation of the diimine ligand on the electronic and photophysical properties of these complexes have also been discussed. Our study revealed that the luminescence performance of these complexes could be significantly enhanced by increasing the rigidity and π‐conjugation of the diimine ligand.
Capillary electrophoresis and phenylboronic acid solid phase extraction for the determination of S‐adenosylmethionine/S‐adenosylhomocysteine ratio in human urine
Authors: Ivanov Alexander Vladimirovich , Virus Edward Danielevich , Nikiforova Ksenya Alexandrovna , Kushlinskii Nicolai Evgenevich , Luzyanin Boris Petrovich , Maksimova Marina Yurievna , Piradov Mikhail Aleksanrovich , Kubatiev Aslan Amirkhanovich
Published: July 2016

An approach that allows direct analysis of the ratio of S‐adenosylmethionine (SAM) and S‐adenosylhomocysteine (SAH) by using CE is presented. The analytes were extracted on phenylboronic acid phase and eluted with 100 mmol/L HCl. CE separation of the analytes took place in the transient isotachophoresis mode with addition of NaCl and meglumine to the samples. The sensitivity (S/N = 3) and quantification limit (S/N = 10) of the method were 0.07 and 0.2 μmol/L, respectively, using a silica capillary with 50 μm internal diameter and 30.5 cm total length. The BGE was 0.02 mol/L Tris with 1 mol/L HCOOH (pH 2.2), and the separation voltage was 15–17 kV. Accuracy of SAM and SAH analysis in urine was 96 and 105%, respectively; interday precision for the SAM/SAH ratio was within 6%. The theoretical plate number exceeded a million. Total analysis time was 8.5 min.
Capillary electrophoresis hyphenated with UV‐native‐laser induced fluorescence detection (CE/UV‐native‐LIF)
Authors: Couderc François , Ong‐Meang Varravaddheay , Poinsot Véréna
Published: July 2016

Native laser‐induced fluorescence using UV lasers associated to CE offers now a large related literature, for now 30 years. The main works have been performed using very expensive Ar‐ion lasers emitting at 257 and 275 nm. They are not affordable for routine analyses, but have numerous applications such as protein, catecholamine, and indolamine analysis. Some other lasers such as HeCd 325 nm have been used but only for few applications. Diode lasers, emitting at 266 nm, cheaper, are extensively used for the same topics, even if the obtained sensitivity is lower than the one observed using the costly UV‐Ar‐ion lasers. This review presents various CE or microchips applications and different UV lasers used for the excitation of native fluorescence. We showed that CE/Native UV laser induced fluorescence detection is very sensitive for detection as well as small aromatic biomolecules than proteins containing Trp and Tyr amino acids. Moreover, it is a simple way to analyze biomolecules without derivatization.
Subgraph selection over coded packet networks with multiple QoS parameters based on DEA
Authors: Raayatpanah M. A.
Published: July 2016

Network coding is a generalisation of conventional routing methods that allows a network node to code information flows before forwarding them. Although network coding could be able to improve the throughput, reliability and security of multicast communications, it does not directly consider the quality of service requirements of multicast routing. In this paper, we study the problem of constructing a subgraph to allocate to coded packets, where several quality of service parameters, for example, bandwidth, delay, profit, packet loss and error rates, are associated with each arc in coded packet networks. For this purpose, we first evaluate the relative efficiency of arcs in the network based on data envelopment analysis techniques to send coded packets. Then, a linear programming model is introduced to determine coding subgraphs with respect to the relative efficiency of the arcs. The proposed approach is illustrated and evaluated through numerical examples. Copyright © 2016 John Wiley & Sons, Ltd.
Taking a positive spin: preserved initiative and performance of everyday activities across mild Alzheimer's, vascular and mixed dementia
Authors: Giebel Clarissa M. , Burns Alistair , Challis David
Published: July 2016

Objectives

The literature commonly evaluates those daily activities which are impaired in dementia. However, in the mild stages, people with dementia (PwD) are still able to initiate and perform many of those tasks. With a lack of research exploring variations between different dementia diagnoses, this study sought to investigate those daily activities with modest impairments in the mild stages and how these compare between Alzheimer's disease (AD), vascular dementia (VaD) and mixed dementia.

Methods

Staff from memory assessment services from nine National Health Service trusts across England identified and approached informal carers of people with mild dementia. Carers completed the newly revised Interview for Deteriorations in Daily Living Activities in Dementia 2 assessing the PwD's initiative and performance of instrumental activities of daily living (IADLs). Data were analysed using analysis of variance and Chi‐square tests to compare the maintenance of IADL functioning across AD, VaD, and mixed dementia.

Results

A total of 160 carers returned the Interview for Deteriorations in Daily Living Activities in Dementia 2, of which 109, 21, and 30 cared for someone with AD, VaD, and mixed dementia, respectively. There were significant variations across subtypes, with AD showing better preserved initiative and performance than VaD for several IADLs. Overall, PwD showed greater preservation of performance than initiative, with tasks such as preparing a hot drink and dressing being best maintained.

Conclusion

Findings can help classify dementia better into subtypes in order to receive bespoke support. It suggests that interventions should primarily address initiative to improve overall functioning. Copyright © 2016 John Wiley & Sons, Ltd.
How does DEM resolution affect microtopographic characteristics, hydrologic connectivity, and modelling of hydrologic processes?
Authors: Habtezion Noah , Tahmasebi Nasab Mohsen , Chu Xuefeng
Published: July 2016

The resolution of a digital elevation model (DEM) is a crucial factor in watershed hydrologic and environmental modelling. DEM resolution can cause significant variability in the representation of surface topography, which further affects quantification of hydrologic connectivity and simulation of hydrologic processes. The objective of this study is to examine the effects of DEM resolution on (1) surface microtopographic characteristics, (2) hydrologic connectivity, and (3) the spatial and temporal variations of hydrologic processes. A puddle‐to‐puddle modelling system was utilized for surface delineation and modelling of the puddle‐to‐puddle overland flow dynamics, surface runoff, infiltration, and unsaturated flow for nine DEM resolution scenarios of a field plot surface. Comparisons of the nine modelling scenarios demonstrated that coarser DEM resolutions tended to eliminate topographic features, reduce surface depression storage, and strengthen hydrologic connectivity and surface runoff. We found that reduction in maximum depression storage and maximum ponding area was as high as 97.56% and 76.36%, respectively, as the DEM grid size increased from 2 to 80 cm. The paired t‐test and fractal analysis demonstrated the existence of a threshold DEM resolution (10 cm for the field plot), within which the DEM‐based hydrologic modelling was effective and acceptable. The effects of DEM resolution were further evaluated for a larger surface in the Prairie Pothole Region subjected to observed rainfall events. It was found that simulations based on coarser resolution DEMs (>10 m) tended to overestimate ponded areas and underestimate runoff discharge peaks. The simulated peak discharge from the Prairie Pothole Region surface reduced by approximately 50% as the DEM resolution changed from 2 to 90 m. Fractal analysis results elucidated scale dependency of hydrologic and topographic processes. In particular, scale analysis highlighted a unique constant–threshold–power relationship between DEM scale and topographic and hydrologic parameters/variables. Not only does this finding allow one to identify threshold DEM but also further develop functional relationships for scaling to achieve valid topographic characterization as well as effective and efficient hydrologic modelling. Copyright © 2016 John Wiley & Sons, Ltd.
Estimating runoff from a glacierized catchment using natural tracers in the semi‐arid Andes cordillera
Authors: Rodriguez Maximiliano , Ohlanders Nils , Pellicciotti Francesca , Williams Mark W. , McPhee James
Published: July 2016

This paper presents a methodology for hydrograph separation in mountain watersheds, which aims at identifying flow sources among ungauged headwater sub‐catchments through a combination of observed streamflow and data on natural tracers including isotope and dissolved solids. Daily summer and bi‐daily spring season water samples obtained at the outlet of the Juncal River Basin in the Andes of Central Chile were analysed for all major ions as well as stable water isotopes, δ18O and δD. Additionally, various samples from rain, snow, surface streams and exfiltrating subsurface water (springs) were sampled throughout the catchment. A principal component analysis was performed in order to address cross‐correlation in the tracer dataset, reduce the dimensionality of the problem and uncover patterns of variability. Potential sources were identified in a two‐component U‐space that explains 94% of the observed tracer variability at the catchment outlet. Hydrograph separation was performed through an Informative‐Bayesian model. Our results indicate that the Juncal Norte Glacier headwater sub‐catchment contributed at least 50% of summer flows at the Juncal River Basin outlet during the 2011–2012 water year (a hydrologically dry period in the Region), even though it accounts for only 27% of the basin area. Our study confirms the value of combining solute and isotope information for estimating source contributions in complex hydrologic systems, and provides insights regarding experimental design in high‐elevation semi‐arid catchments. The findings of this study can be useful for evaluating modelling studies of the hydrological consequences of the rapid decrease in glacier cover observed in this region, by providing insights into the origin of river water in basins with little hydrometeorological information. Copyright © 2016 John Wiley & Sons, Ltd.
Small Molecule Crystallography in the Laboratory of Organic Chemistry at ETH Zürich
Authors: Diederich François , Trapp Nils , Wörle Michael
Published: July 2016

The development of small‐molecule crystallography in the Laboratory of Organic Chemistry (LOC) at ETH since its foundation by Jack Dunitz in 1957 is reported. We briefly review the scientific path of Dunitz before coming to ETH and subsequently illustrate research highlights until his retirement in 1990. Together with his doctoral students and postdoctoral fellows, Dunitz developed X‐ray crystallography as a tool for studying chemical reactivity and reaction mechanisms, stereochemical, and in particular, conformational analysis, and supramolecular interactions. He hosted numerous leaders in the field in Zurich. After retirement, Dunitz remained highly research‐active. The crystallography facilities were run in 1991–2013 by his former coworkers Bernd Schweizer and Paul Seiler. In 2013, the Small Molecule Crystallography Center (SMoCC) was founded by merging the X‐ray facilities in inorganic and organic chemistry and its research‐driven service is illustrated.