bluuebunny/crossref_metadata_2025 huggingface dataset:
THE FORMATION AND USE OF DROMOI IN EARLY MYCENAEAN TOMBS
Authors: Papadimitriou Nikolas
Published: November 2015

The paper examines how the dromos emerged as an architectural feature in Mycenaean tombs and why it became the standard type of access device. It focuses on collective tombs with lateral entrances of LH I and transitional LH I/IIA date in mainland Greece, but considers also a number of MH tombs with side entrances. The first part discusses the architectural evidence. The second part examines permanent installations and evidence of possible ritual activities from dromoi. The third part explores the symbolic and performative aspects of dromoi. It is argued that the dromos was not an integral part of Mycenaean funerary architecture from the very beginning, but came about gradually out of a long process of experimentation, which originated in MH tumuli and was completed in late LH I or LH I/IIA tholoi and chamber tombs. This process merged different building traditions and combined practical considerations with new ritual needs arising at a period of intense social and cultural change.
No one to fill my shoes: narrative practices of three ageing Australian male farmers
Authors: O'CALLAGHAN ZOE , WARBURTON JENI
Published: November 2015

Ageing Australian farmers face many uncertainties associated with wider social, economic and climate change. Significantly for many farmers, ageing means the end not only of a life-long occupation but the end of the farm that has often been in the family for many generations. In turn, the prospect of this discontinuity breaches long-held cultural images of Australian farming and farmers. For individual male farmers approaching retirement age, the lack of succession and discontinuation of the family's ownership of, and attachment to the land, poses threats for social and personal identity. This paper examines the narratives of three male, baby-boom Australian farmers to tease out the impact of ageing and the possible loss of the family farm on the ways that they construct their situations and their self-identity. It illustrates the narrative practices that these men employ as they work to validate their self-identities within particular narrative environments, and through a range of outmoded and contemporary material conditions that mediate their selves and lives. The approach exemplified in this paper focuses on the processes and phases of analysis to show how the farmers craft their narrative as well as the individuality, complexity and coherence of their accounts.
Leben mit Achondroplasie
Authors: Rohenkohl Anja C. , Sommer Rachel , Bestges Stephanie , Kahrs Sabine , Klingebiel Karl-Heinz , Bullinger Monika , Quitmann Julia
Published: November 2015

Zusammenfassung. Fragestellung: Über die gesundheitsbezogene Lebensqualität und Verhaltensauffälligkeiten und -stärken von kleinwüchsigen Kindern, Jugendlichen und jungen Erwachsenen mit der Diagnose Achondroplasie ist bisher wenig bekannt. Die Untersuchung dieser Konstrukte aus Sicht der Betroffenen und die Identifikation möglicher Einflussfaktoren ist Ziel dieser Arbeit. Methodik: Auf Einladung einer Selbsthilfeorganisation nahmen 89 (junge) Menschen mit Kleinwuchs im Alter von 8 bis 28 Jahren und ihre Eltern an der Befragung teil. Die Lebensqualität (LQ) wurde im Querschnitt mit generischen und krankheitsbezogenen Instrumenten erfragt, Verhaltensauffälligkeiten und -stärken anhand des SDQ (Strengths and Difficulties Questionnaire). Neben deskriptiven Analysen erfolgte ein Vergleich mit repräsentativen Norm- bzw. Referenzdaten. In eine hierarchische Regressionsanalyse zur Vorhersage der Lebensqualität wurden soziodemografische, klinische und psychologische Variablen aufgenommen. Ergebnisse: Die Betroffenen unterschieden sich in ihrer LQ und in Bezug auf ihre Verhaltensauffälligkeiten und -stärken nicht signifikant von den Normstichproben. Jedoch berichteten sie im Vergleich zu den von endokrinem Kleinwuchs Betroffenen über stärkere Verhaltensprobleme und Einschränkungen im physischen und sozialen Bereich der LQ. Die Hinzunahme psychologischer Variablen wie soziale Unterstützung und Einstellung zur Größe erbrachte die höchste Varianzaufklärung der LQ. Schlussfolgerungen: Junge Menschen mit Achondroplasie beschreiben ihre LQ und Verhaltensauffälligkeiten und -stärken nicht anders als Nichtbetroffene. Merkmale wie die Körpergröße erscheinen weniger bedeutsam für die LQ als Verhaltensauffälligkeiten und -stärken sowie protektive psychosoziale Faktoren.
Experimental fault-tolerant universal quantum gates with solid-state spins under ambient conditions
Authors: Rong Xing , Geng Jianpei , Shi Fazhan , Liu Ying , Xu Kebiao , Ma Wenchao , Kong Fei , Jiang Zhen , Wu Yang , Du Jiangfeng
Published: November 2015

Quantum computation provides great speedup over its classical counterpart for certain problems. One of the key challenges for quantum computation is to realize precise control of the quantum system in the presence of noise. Control of the spin-qubits in solids with the accuracy required by fault-tolerant quantum computation under ambient conditions remains elusive. Here, we quantitatively characterize the source of noise during quantum gate operation and demonstrate strategies to suppress the effect of these. A universal set of logic gates in a nitrogen-vacancy centre in diamond are reported with an average single-qubit gate fidelity of 0.999952 and two-qubit gate fidelity of 0.992. These high control fidelities have been achieved at room temperature in naturally abundant 13C diamond via composite pulses and an optimized control method.
Evolution and control of the phase competition morphology in a manganite film
Authors: Zhou Haibiao , Wang Lingfei , Hou Yubin , Huang Zhen , Lu Qingyou , Wu Wenbin
Published: November 2015

The competition among different phases in perovskite manganites is pronounced since their energies are very close under the interplay of charge, spin, orbital and lattice degrees of freedom. To reveal the roles of underlying interactions, many efforts have been devoted towards directly imaging phase transitions at microscopic scales. Here we show images of the charge-ordered insulator (COI) phase transition from a pure ferromagnetic metal with reducing field or increasing temperature in a strained phase-separated manganite film, using a home-built magnetic force microscope. Compared with the COI melting transition, this reverse transition is sharp, cooperative and martensitic-like with astonishingly unique yet diverse morphologies. The COI domains show variable-dimensional growth at different temperatures and their distribution can illustrate the delicate balance of the underlying interactions in manganites. Our findings also display how phase domain engineering is possible and how the phase competition can be tuned in a controllable manner.
Attenuation of Histone Methyltransferase KRYPTONITE-mediated transcriptional gene silencing by Geminivirus
Authors: Sun Yan-Wei , Tee Chuan-Sia , Ma Yong-Huan , Wang Gang , Yao Xiang-Mei , Ye Jian
Published: November 2015

Although histone H3K9 methylation has been intensively studied in animals and a model plant Arabidopsis thaliana, little is known about the evolution of the histone methyltransferase and its roles in plant biotic stress response. Here we identified a Nicotiana benthamiana homolog of H3K9 histone methyltransferase KRYPTONITE (NbKYP) and demonstrated its fundamental roles on methylation of plant and virus, beside of leading to the suppression of endogenous gene expression and virus replication. NbKYP and another gene encoding DNA methyltransferase CHROMOMETHYLTRANSFERASE 3 (NbCMT3-1) were further identified as the key components of maintenance of transcriptional gene silencing, a DNA methylation involved anti-virus machinery. All three types of DNA methylations (asymmetric CHH and symmetric CHG/CG) were severely affected in NbKYP-silenced plants, but only severe reduction of CHG methylation found in NbCMT3-1-silenced plants. Attesting to the importance of plant histone H3K9 methylation immunity to virus, the virulence of geminiviruses requires virus-encoded trans-activator AC2 which inhibits the expression of KYP via activation of an EAR-motif-containing transcription repressor RAV2 (RELATED TO ABI3 and VP1). The reduction of KYP was correlated with virulence of various similar geminiviruses. These findings provide a novel mechanism of how virus trans-activates a plant endogenous anti-silencing machinery to gain high virulence.
Quantifying the Impact of Scenic Environments on Health
Authors: Seresinhe Chanuki Illushka , Preis Tobias , Moat Helen Susannah
Published: November 2015

Few people would deny an intuitive sense of increased wellbeing when spending time in beautiful locations. Here, we ask: can we quantify the relationship between environmental aesthetics and human health? We draw on data fromScenic-Or-Not, a website that crowdsources ratings of “scenicness” for geotagged photographs across Great Britain, in combination with data on citizen-reported health from the Census for England and Wales. We find that inhabitants of more scenic environments report better health, across urban, suburban and rural areas, even when taking core socioeconomic indicators of deprivation into account, such as income, employment and access to services. Our results provide evidence in line with the striking hypothesis that the aesthetics of the environment may have quantifiable consequences for our wellbeing.
An unexpected role for mixotrophs in the response of peatland carbon cycling to climate warming
Authors: Jassey Vincent E. J. , Signarbieux Constant , Hättenschwiler Stephan , Bragazza Luca , Buttler Alexandre , Delarue Frédéric , Fournier Bertrand , Gilbert Daniel , Laggoun-Défarge Fatima , Lara Enrique , T. E. Mills Robert , Mitchell Edward A. D. , Payne Richard J. , Robroek Bjorn J. M.
Published: November 2015

Mixotrophic protists are increasingly recognized for their significant contribution to carbon (C) cycling. As phototrophs they contribute to photosynthetic C fixation, whilst as predators of decomposers, they indirectly influence organic matter decomposition. Despite these direct and indirect effects on the C cycle, little is known about the responses of peatland mixotrophs to climate change and the potential consequences for the peatland C cycle. With a combination of field and microcosm experiments, we show that mixotrophs in the Sphagnum bryosphere play an important role in modulating peatland C cycle responses to experimental warming. We found that five years of consecutive summer warming with peaks of +2 to +8°C led to a 50% reduction in the biomass of the dominant mixotrophs, the mixotrophic testate amoebae (MTA). The biomass of other microbial groups (including decomposers) did not change, suggesting MTA to be particularly sensitive to temperature. In a microcosm experiment under controlled conditions, we then manipulated the abundance of MTA and showed that the reported 50% reduction of MTA biomass in the field was linked to a significant reduction of net C uptake (-13%) of the entire Sphagnum bryosphere. Our findings suggest that reduced abundance of MTA with climate warming could lead to reduced peatland C fixation.
Photoinhibition of Phaeocystis globosa resulting from oxidative stress induced by a marine algicidal bacterium Bacillus sp. LP-10
Authors: Guan Chengwei , Guo Xiaoyun , Li Yi , Zhang Huajun , Lei Xueqian , Cai Guanjing , Guo Jiajia , Yu Zhiming , Zheng Tianling
Published: November 2015

Harmful algal blooms caused by Phaeocystis globosa have resulted in staggering losses to coastal countries because of their world-wide distribution. Bacteria have been studied for years to control the blooms of harmful alga, however, the action mechanism of them against harmful algal cells is still not well defined. Here, a previously isolated algicidal bacterium Bacillus sp. LP-10 was used to elucidate the potential mechanism involved in the dysfunction of P. globosa algal cells at physiological and molecular levels. Our results showed Bacillus sp. LP-10 induced an obvious rise of reactive oxygen species (ROS), which was supposed to be major reason for algal cell death. Meanwhile, the results revealed a significant decrease of photosynthetic physiological indexes and apparent down-regulated of photosynthesis-related genes (psbA and rbcS) and protein (PSII reaction center protein D1), after treated by Bacillus sp. LP-10 filtrates, suggesting photoinhibition occurred in the algal cells. Furthermore, our results indicated that light played important roles in the algal cell death. Our work demonstrated that the major lethal reason of P. globosa cells treated by the algicidal bacterium was the photoinhibition resulted from oxidative stress induced by Bacillus sp. LP-10.
Drowning is an apparent and unexpected recurrent cause of mass mortality of Common starlings (Sturnus vulgaris)
Authors: Lawson Becki , Duff J. Paul , Beckmann Katie M. , Chantrey Julian , Peck Kirsi M. , Irvine Richard M. , Robinson Robert A. , Cunningham Andrew A.
Published: November 2015

Drowning is infrequently reported as a cause of death of wild birds and such incidents typically involve individual, rather than multiple, birds. Over a 21-year period (1993 to 2013 inclusive), we investigated 12 incidents of mortality of multiple (2 − 80+) Common starlings (Sturnus vulgaris) in Great Britain that appeared to be due to drowning. More than ten birds were affected in ten of these reported incidents. These incidents always occurred during the spring and early summer months and usually involved juvenile birds. In all cases, circumstantial evidence and post-mortem examinations indicated drowning to be the most likely cause of death with no underlying disease found. A behavioural explanation seems likely, possibly related to the gregarious nature of this species combined with juvenile inexperience in identifying water hazards. A review of data from the ringed bird recovery scheme across Great Britain (1909–2013 inclusive) of both starlings and Common blackbirds (Turdus merula), also a common garden visitor, identified additional suspected drowning incidents, which were significantly more common in the former species, supporting a species predisposition to drowning. For each species there was a marked seasonal peak from April to August. Drowning should be included as a differential diagnosis when investigating incidents of multiple starling mortality, especially of juveniles.
Optical detection of individual ultra-short carbon nanotubes enables their length characterization down to 10 nm
Authors: Gao Zhenghong , Oudjedi Laura , Faes Romain , Moroté Fabien , Jaillet Christèle , Poulin Philippe , Lounis Brahim , Cognet Laurent
Published: November 2015

Ultrashort single-walled carbon nanotubes, i.e. with length below ~30 nm, display length-dependent physical, chemical and biological properties that are attractive for the development of novel nanodevices and nanomaterials. Whether fundamental or applicative, such developments require that ultrashort nanotube lengths can be routinely and reliably characterized with high statistical data for high-quality sample production. However, no methods currently fulfill these requirements. Here, we demonstrate that photothermal microscopy achieves fast and reliable optical single nanotube analysis down to ~10 nm lengths. Compared to atomic force microscopy, this method provides ultrashort nanotubes length distribution with high statistics and neither requires specific sample preparation nor tip-dependent image analysis.
Effect of conservation efforts and ecological variables on waterbird population sizes in wetlands of the Yangtze River
Authors: Zhang Yong , Jia Qiang , Prins Herbert H. T. , Cao Lei , de Boer Willem Frederik
Published: November 2015

Forage quality and availability, climatic factors and a wetland’s conservation status are expected to affect the densities of wetland birds. However, the conservation effectiveness is often poorly studied. Here, using twelve years’ census data collected from 78 wetlands in the Yangtze River floodplain, we aimed to understand the effect of these variables on five Anatidae species and evaluate the effectiveness of the conservation measures by comparing population trends of these species among wetlands that differ in conservations status. We showed that the slope angle of a wetland and the variation thereof best explain the differences in densities of four species. We also found that the population abundances of the Anatidae species generally declined in wetlands along the Yangtze River floodplain over time, with a steeper decline in wetlands with a lower protection status, indicating that current conservation policies might deliver benefits for wintering Anatidae species in China, as population sizes of the species were buffered to some extent against decline in numbers in wetlands with a higher level protection status. We recommend several protection measures to stop the decline of these Anatidae species in wetlands along the Yangtze River floodplain, which are of great importance for the East Asian-Australasian Flyway.
Spatial-frequency dependent binocular imbalance in amblyopia
Authors: Kwon MiYoung , Wiecek Emily , Dakin Steven C. , Bex Peter J.
Published: November 2015

While amblyopia involves both binocular imbalance and deficits in processing high spatial frequency information, little is known about the spatial-frequency dependence of binocular imbalance. Here we examined binocular imbalance as a function of spatial frequency in amblyopia using a novel computer-based method. Binocular imbalance at four spatial frequencies was measured with a novel dichoptic letter chart in individuals with amblyopia, or normal vision. Our dichoptic letter chart was composed of band-pass filtered letters arranged in a layout similar to the ETDRS acuity chart. A different chart was presented to each eye of the observer via stereo-shutter glasses. The relative contrast of the corresponding letter in each eye was adjusted by a computer staircase to determine a binocularBalance Pointat which the observer reports the letter presented to either eye with equal probability. Amblyopes showed pronounced binocular imbalance across all spatial frequencies, with greater imbalance at high compared to low spatial frequencies (an average increase of 19%,p < 0.01). Good test-retest reliability of the method was demonstrated by the Bland-Altman plot. Our findings suggest that spatial-frequency dependent binocular imbalance may be useful for diagnosing amblyopia and as an outcome measure for recovery of binocular vision following therapy.
A new application of click chemistry in situ: development of fluorescent probe for specific G-quadruplex topology
Authors: Hu Ming-Hao , Chen Xiao , Chen Shuo-Bin , Ou Tian-Miao , Yao Meicun , Gu Lian-Quan , Huang Zhi-Shu , Tan Jia-Heng
Published: November 2015

Target-guided synthesis is an approach to drug discovery that allows the target to self-assemble its own binding agents. So far, target-guided synthesis and especially in situ click chemistry have attracted extensive attention and have led to the identification of highly potent inhibitors for proteins. In this study, we expand the application of in situ click chemistry and present a procedure using this approach to identify selective fluorescent probes for a specific topology of G-quadruplex nucleic acids, the parallel G-quadruplexes. On this basis, compound 15 assembled by triarylimidazole scaffold and carboxyl side chain was a positive hit, demonstrating highly potential in the sensitive and selective detection of parallel G-quadruplexes. Such selective fluorescence response can be rationalized in terms of different binding affinities between 15 and G-quadruplexes. Our work accordingly represents a new development towards the application of in situ click chemistry to develop selective fluorescent probes and may also shed light on the search for probes for a specific G-quadruplex topology.
Exploring the Effects on Lipid Bilayer Induced by Noble Gases via Molecular Dynamics Simulations
Authors: Chen Junlang , Chen Liang , Wang Yu , Wang Xiaogang , Zeng Songwei
Published: November 2015

Noble gases seem to have no significant effect on the anesthetic targets due to their simple, spherical shape. However, xenon has strong narcotic efficacy and can be used clinically, while other noble gases cannot. The mechanism remains unclear. Here, we performed molecular dynamics simulations on phospholipid bilayers with four kinds of noble gases to elucidate the difference of their effects on the membrane. Our results showed that the sequence of effects on membrane exerted by noble gases from weak to strong was Ne, Ar, Kr and Xe, the same order as their relative narcotic potencies as well as their lipid/water partition percentages. Compared with the other three kinds of noble gases, more xenon molecules were distributed between the lipid tails and headgroups, resulting in membrane’s lateral expansion and lipid tail disorder. It may contribute to xenon’s strong anesthetic potency. The results are well consistent with the membrane mediated mechanism of general anesthesia.
Laser jetting of femto-liter metal droplets for high resolution 3D printed structures
Authors: Zenou M. , Sa’ar A. , Kotler Z.
Published: November 2015

Laser induced forward transfer (LIFT) is employed in a special, high accuracy jetting regime, by adequately matching the sub-nanosecond pulse duration to the metal donor layer thickness. Under such conditions, an effective solid nozzle is formed, providing stability and directionality to the femto-liter droplets which are printed from a large gap in excess of 400 μm. We illustrate the wide applicability of this method by printing several 3D metal objects. First, very high aspect ratio (A/R > 20), micron scale, copper pillars in various configuration, upright and arbitrarily bent, then a micron scale 3D object composed of gold and copper. Such a digital printing method could serve the generation of complex, multi-material, micron-scale, 3D materials and novel structures.
Cognitive dysfunction and health-related quality of life among older Chinese
Authors: Pan Chen-Wei , Wang Xingzhi , Ma Qinghua , Sun Hong-Peng , Xu Yong , Wang Pei
Published: November 2015

We aimed to assess the association of cognitive dysfunction with health-related quality of life (HRQOL) among older adults in China. We analyzed community-based cross-sectional data of 5,557 Chinese individuals aged 60 years and above in the Weitang Geriatric Diseases Study. Cognitive dysfunction and HRQOL were assessed using the Abbreviated Mental Test (AMT) and the European Quality of Life-5 dimensions (EQ-5D), respectively. We estimated the impacts of cognitive dysfunction on the EQ-5D index and visual analogue scale (VAS) scores using linear regression models and the association between cognitive dysfunction and self-reported EQ-5D health problems using logistic regression models. The EQ-5D index and VAS scores were significantly lower for individuals with cognitive dysfunction than their counterparts. After controlling for covariates, the differences in EQ-5D index and VAS scores between individuals with and without cognitive dysfunction were −0.016 (95% confidence interval [CI]: −0.024, −0.008) and −3.4 (95% CI: −4.5, −2.4), respectively. Cognitive dysfunction was associated with reporting of problems in pain/discomfort (odds ration [OR]: 1.37; 95% CI: 1.12, 1.69) and anxiety/depression (OR: 2.13; 95% CI: 1.41, 3.23). The negative impact on HRQOL increased with the severity of cognitive dysfunction. The results indicate cognitive dysfunction was associated with worse HRQOL in older adults.
Facile synthesis of CuCo2S4 as a novel electrode material for ultrahigh supercapacitor performance
Authors: Tang Jianhua , Ge Yuancai , Shen Jianfeng , Ye Mingxin
Published: November 2015

CuCo2S4 nanoparticles demonstrating outstanding electrochemical performances were firstly synthesized through a simple solvothermal approach without using any templates.
Degradation and mineralization of methylene blue using a heterogeneous photo-Fenton catalyst under visible and solar light irradiation
Authors: Ahmed Yunus , Yaakob Zahira , Akhtar Parul
Published: November 2015

A SiO2-supported Fe and Ni bimetallic catalyst has been synthesized, characterized and, for the first time, tested as a heterogeneous photo-Fenton catalyst for the degradation and mineralization of methylene blue (MB) dye.
Chemosensors containing appended benzothiazole group(s): selective binding of Cu2+and Zn2+ions by two related receptors
Authors: Bansal Deepak , Gupta Rajeev
Published: November 2015

Amide-benzothiazole based molecules act as highly selective chemosensors for Cu(ii) and Zn(ii) ions both in solution and in the solid-state.
Remarkable stability of tetrabenzo[a,c,g,i]fluorenyl ammonium salts in water: syntheses, reactions, and crystal structures
Authors: Frey Okko N. , Stalling Timo , Schlüter Florian , Saak Wolfgang , Schmidtmann Marc , Haase Detlev , Beckhaus Rüdiger
Published: November 2015

Deprotonation of 8bH-tetrabenzo[a,c,g,i]fluorene (8bH-Tbf), a large benzannulated cyclopentadienyl derivative, by [NR3R′][OH] (R = nBu, Et; R′ = nBu, Et, Bn) leads to a series of Tbf ammonium salts of the type [NR3R′][Tbf].
Supercritical fluid rectification of lignin pyrolysis oil methyl ether (LOME) and its use as a bio-derived aprotic solvent
Authors: Mudraboyina Bhanu P. , Farag Sherif , Banerjee Abhinandan , Chaouki Jamal , Jessop Philip G.
Published: November 2015

Lignin can be converted by pyrolysis, supercritical rectification, and methylation, into an aromatic bio-derived solvent.
Silver(i) complexes with quinazoline and phthalazine: synthesis, structural characterization and evaluation of biological activities
Authors: Savić Nada D. , Glišić Biljana Đ. , Wadepohl Hubert , Pavic Aleksandar , Senerovic Lidija , Nikodinovic-Runic Jasmina , Djuran Miloš I.
Published: November 2015

New silver(i) complexes with quinazoline and phthalazine have been synthesized, characterized and evaluated for their antimicrobial activity and their effect on the viability of fibroblasts and the development of zebrafish embryos.
Off–on fluorometric detection of cyanide anions in an aqueous mixture by an indane-based receptor
Authors: Shiraishi Yasuhiro , Nakamura Masaya , Kogure Tetsuri , Hirai Takayuki
Published: November 2015

An indanedione–coumarin conjugate behaves as an off–on type fluorescent receptor for rapid, selective, and sensitive detection of cyanide anions in an aqueous mixture via a nucleophilic interaction with the electrophilic β-carbon of the receptor.
Synthesis and characterization of castor oil based hybrid polymers and their polyurethane–urea/silica coatings
Authors: Bhosale Nikita , Shaik Allauddin , Mandal Sisir Kumar
Published: November 2015

Novel acrylated alkoxysilane castor oil with hydrolysable –Si–OCH3 was synthesized via free radical copolymerization. This silane functional castor oil was further reacted with isocyanate to get isocyanate terminated silica hybrid polyurethane–urea prepolymer.
Sol–gel synthesis of transition-metal ion conjugated alumina-rich mullite nanocomposites with potential mechanical, dielectric and photoluminescence properties
Authors: Kool Arpan , Thakur Pradip , Bagchi Biswajoy , Hoque Nur Amin , Banerjee Somtirtha , Das Sukhen
Published: November 2015

Mechanical, dielectric and photoluminescence properties of transition-metal ions doped mullite nanocomposite synthesized via alkoxide hydrolysis.
The effect of a capillary bridge on the crack opening of a penny crack
Authors: Yang Fuqian , Zhao Ya-Pu
Published: November 2015

Young's relation is based of the equilibrium of the horizontal components of surface tensions for a liquid droplet on a “rigid” substrate without addressing the substrate deformation induced by the net vertical component of surface tensions. The net vertical component of the surface tensions can introduce a surface ridge around a contact line.
Biomass-derived activated carbon with simultaneously enhanced CO2 uptake for both pre and post combustion capture applications
Authors: Coromina Helena Matabosch , Walsh Darren A. , Mokaya Robert
Published: November 2015

Activated carbons from biomass (grass and Camellia japonica) exhibit enhanced CO2 uptake at 25 °C; up to 1.5 mmol g−1 at 0.15 bar, 5.0 mmol g−1 at 1 bar and 21.1 mmol g−1 at 20 bar, and depending on level of activation, have excellent uptake at both low (≤1 bar) and high (20 bar) pressure.
Probabilistic multi‐objective HVDC/AC transmission expansion planning considering distant wind/solar farms
Authors: Doagou‐Mojarrad Hasan , Rastegar Hasan , Gharehpetian Gevork B.
Published: November 2015

This study presents a new binary differential evolution algorithm for probabilistic AC/DC transmission expansion planning (TEP). The probabilistic model would consider the uncertainty of distant wind/solar energy resources as well as load demand. In many power systems, the necessity of considering the impacts of HVDC links on the TEP studies is inevitable. Therefore, in this study, these links are considered a substitute candidate for the conventional HVAC transmission lines. The stochastic modelling and integration of HVDC links for TEP problem have introduced new challenges to transmission system planners. To overcome these problems, an efficient fuzzy set‐based optimisation technique is used to solve the multi‐objective TEP problem. Finally, the proposed method is applied to the test system consisting of 24 buses.
Dynamic trajectory analysis of superparamagnetic beads driven by on-chip micromagnets
Authors: Hu Xinghao , Abedini-Nassab Roozbeh , Lim Byeonghwa , Yang Ye , Howdyshell Marci , Sooryakumar Ratnasingham , Yellen Benjamin B. , Kim CheolGi
Published: November 2015

We investigate the non-linear dynamics of superparamagnetic beads moving around the periphery of patterned magnetic disks in the presence of an in-plane rotating magnetic field. Three different dynamical regimes are observed in experiments, including (1) phase-locked motion at low driving frequencies, (2) phase-slipping motion above the first critical frequency fc1, and (3) phase-insulated motion above the second critical frequency fc2. Experiments with Janus particles were used to confirm that the beads move by sliding rather than rolling. The rest of the experiments were conducted on spherical, isotropic magnetic beads, in which automated particle position tracking algorithms were used to analyze the bead dynamics. Experimental results in the phase-locked and phase-slipping regimes correlate well with numerical simulations. Additional assumptions are required to predict the onset of the phase-insulated regime, in which the beads are trapped in closed orbits; however, the origin of the phase-insulated state appears to result from local magnetization defects. These results indicate that these three dynamical states are universal properties of bead motion in non-uniform oscillators.
DksA regulates RNA polymerase in
Escherichia coli
through a network of interactions in the secondary channel that includes Sequence Insertion 1
Authors: Parshin Andrey , Shiver Anthony L. , Lee Jookyung , Ozerova Maria , Schneidman-Duhovny Dina , Gross Carol A. , Borukhov Sergei
Published: November 2015

Significance

The transcription factor DksA is a critical determinant of the stringent response and is essential for virulence in many pathogenic proteobacteria. This ubiquitous transcription factor is also a model system for transcription regulation, making it essential to understand how DksA interacts with RNA polymerase (RNAP) at the molecular level. High-resolution structural information of the DksA–RNAP interaction is currently unavailable. Using genetic, biochemical, and computational approaches, we have generated a new high-quality model of the DksA–RNAP interaction that advances our understanding of DksA binding and activity and will serve as a springboard for future mechanistic investigations into DksA regulation.
Electrical active defects in HfO2 based metal/oxide/metal devices
Authors: El Kamel F
Published: November 2015

Dielectric as well as thermally stimulated current measurements were performed on metal/HfO2/Pt capacitors in order to study the electrical active defects in hafnia thin films. Two thermally activated relaxation processes have been carried out from both measurements. At low temperatures, the relaxation process can be ascribed to the shallow traps level localized at 0.65 eV and generally evidenced by the second ionization of oxygen vacancies. At high temperatures, the relaxation process arises from the diffusion of positively charged oxygen vacancies by overcoming an energetic barrier of about 1 eV.
Matroid configurations and symbolic powers of their ideals
Authors: Geramita A. , Harbourne B. , Migliore J. , Nagel U.
Published: November 2015

Star configurations are certain unions of linear subspaces of projective space that have been studied extensively. We develop a framework for studying a substantial generalization, which we call matroid configurations, whose ideals generalize Stanley-Reisner ideals of matroids. Such a matroid configuration is a union of complete intersections of a fixed codimension. Relating these to the Stanley-Reisner ideals of matroids and using methods of liaison theory allows us, in particular, to describe the Hilbert function and minimal generators of the ideal of, what we call, a hypersurface configuration. We also establish that the symbolic powers of the ideal of any matroid configuration are Cohen-Macaulay. As applications, we study ideals coming from certain complete hypergraphs and ideals derived from tetrahedral curves. We also consider Waldschmidt constants and resurgences. In particular, we determine the resurgence of any star configuration and many hypersurface configurations. Previously, the only non-trivial cases for which the resurgence was known were certain monomial ideals and ideals of finite sets of points. Finally, we point out a connection to secant varieties of varieties of reducible forms.
Opportunities to Create New General Surgery Residency Programs to Alleviate the Shortage of General Surgeons
Authors: Meagher Ashley D. , Beadles Christopher A. , Sheldon George F. , Charles Anthony G.
Published: November 2015

Purpose

To estimate the capacity for supporting new general surgery residency programs among U.S. hospitals that currently do not have such programs.

Method

The authors compiled 2011 American Hospital Association data regarding the characteristics of hospitals with and without a general surgery residency program and 2012 Accreditation Council for Graduate Medical Education data regarding existing general surgery residencies. They performed an ordinary least squares regression to model the number of residents who could be trained at existing programs on the basis of residency program-level variables. They identified candidate hospitals on the basis of a priori defined criteria for new general surgery residency programs and an out-of-sample prediction of resident capacity among the candidate hospitals.

Results

The authors found that 153 hospitals in 39 states could support a general surgery residency program. The characteristics of these hospitals closely resembled the characteristics of hospitals with existing programs. They identified 435 new residency positions: 40 hospitals could support 2 residents per year, 99 hospitals could support 3 residents, 12 hospitals could support 4 residents, and 2 hospitals could support 5 residents. Accounting for progressive specialization, new residency programs could add 287 additional general surgeons to the workforce annually (after an initial five- to seven-year lead time).

Conclusions

By creating new general surgery residency programs, hospitals could increase the number of general surgeons entering the workforce each year by 25%. A challenge to achieving this growth remains finding new funding mechanisms within and outside Medicare. Such changes are needed to mitigate projected workforce shortages.
Stochastic focusing coupled with negative feedback enables robust regulation in biochemical reaction networks
Authors: Milias-Argeitis Andreas , Engblom Stefan , Bauer Pavol , Khammash Mustafa
Published: November 2015

Nature presents multiple intriguing examples of processes that proceed with high precision and regularity. This remarkable stability is frequently counter to modellers' experience with the inherent stochasticity of chemical reactions in the regime of low-copy numbers. Moreover, the effects of noise and nonlinearities can lead to ‘counterintuitive’ behaviour, as demonstrated for a basic enzymatic reaction scheme that can display
stochastic focusing
(SF). Under the assumption of rapid signal fluctuations, SF has been shown to convert a graded response into a threshold mechanism, thus attenuating the detrimental effects of signal noise. However, when the rapid fluctuation assumption is violated, this gain in sensitivity is generally obtained at the cost of very large product variance, and this unpredictable behaviour may be one possible explanation of why, more than a decade after its introduction, SF has still not been observed in real biochemical systems. In this work, we explore the noise properties of a simple enzymatic reaction mechanism with a small and fluctuating number of active enzymes that behaves as a high-gain, noisy amplifier due to SF caused by slow enzyme fluctuations. We then show that the inclusion of a plausible negative feedback mechanism turns the system from a noisy signal detector to a strong homeostatic mechanism by exchanging high gain with strong attenuation in output noise and robustness to parameter variations. Moreover, we observe that the discrepancy between deterministic and stochastic descriptions of stochastically focused systems in the evolution of the means almost completely disappears, despite very low molecule counts and the additional nonlinearity due to feedback. The reaction mechanism considered here can provide a possible resolution to the apparent conflict between intrinsic noise and high precision in critical intracellular processes.
The impact of antiretroviral therapy on population-level virulence evolution of HIV-1
Authors: Roberts Hannah E. , Goulder Philip J. R. , McLean Angela R.
Published: November 2015

In HIV-infected patients, an individual's set point viral load (SPVL) strongly predicts disease progression. Some think that SPVL is evolving, indicating that the virulence of the virus may be changing, but the data are not consistent. In addition, the widespread use of antiretroviral therapy (ART) has the potential to drive virulence evolution. We develop a simple deterministic model designed to answer the following questions: what are the expected patterns of virulence change in the initial decades of an epidemic? Could administration of ART drive changes in virulence evolution and, what is the potential size and direction of this effect? We find that even without ART we would not expect monotonic changes in average virulence. Transient decreases in virulence following the peak of an epidemic arenotnecessarily indicative of eventual evolution to avirulence. In the short term, we would expect widespread ART to cause limited downward pressure on virulence. In the long term, the direction of the effect is determined by a threshold condition, which we define. We conclude that, given the surpassing benefits of ART to the individual and in reducing onward transmission, virulence evolution considerations need have little bearing on how we treat.
Electrical method to control the running direction and speed of self-powered tiny liquid metal motors
Authors: Tan Si-Cong , Yuan Bin , Liu Jing
Published: November 2015

The motion control of small motors in solution is significant for various applications, ranging from microfluidics, smart machines, to tiny robot. Here, we propose an electrical controlling method to flexibly manipulate liquid metal motors powered with aluminium. It was discovered that adding aluminium to liquid metal droplets would significantly magnify its electric controlling capability, which provides dozens of times' driving force compared to pure GaIn10droplets. After switching on the electrical field, the aluminium powered liquid metal droplet would accelerate its running speed to an extremely high magnitude, e.g. 43 cm s−1under 20 V voltage, as measured in a channel with 1 cm width and filled with aqueous solution. In addition, we also observed that the motion trajectories of the motors in the free space of a Petri dish nearly reflect the electric field lines in the electrolyte, which suggests an important and straightforward way to visualize such complex physical property. Lastly, the oscillating motion behaviour of the motor under a small electrical voltage and its continuous running modality were experimentally discriminated and interpreted. The current findings on the Al–Ga–In motors generate profound impact on developing future microfluidic systems or tiny soft robots that are hard to achieve otherwise through conventional strategies.
Critical value of the generalized stress intensity factor for a crack perpendicular to an interface
Authors: Adams George G.
Published: November 2015

When a crack tip impinges upon a bi-material interface, the order of the stress singularity will be equal to, less than or greater than one-half. The generalized stress intensity factors have already been determined for some such configurations, including when a finite-length crack is perpendicular to the interface. However, for these non-square-root singular stresses, the determination of the conditions for crack growth are not well established. In this investigation, the critical value of the generalized stress intensity factor for tensile loading is related to the work of adhesion by using a cohesive zone model in an asymptotic analysis of the separation near the crack tip. It is found that the critical value of the generalized stress intensity factor depends upon the maximum stress of the cohesive zone model, as well as on the Dundurs parameters (αandβ). As expected this dependence on the cohesive stress vanishes as the material contrast is reduced, in which case the order of the singularity approaches one-half.
Nature of the coupling between neural drive and force-generating capacity in the human quadriceps muscle
Authors: Hug François , Goupille Clément , Baum Daniel , Raiteri Brent J. , Hodges Paul W. , Tucker Kylie
Published: November 2015

The force produced by a muscle depends on both the neural drive it receives and several biomechanical factors. When multiple muscles act on a single joint, the nature of the relationship between the neural drive and force-generating capacity of the synergistic muscles is largely unknown. This study aimed to determine the relationship between the ratio of neural drive and the ratio of muscle force-generating capacity between two synergist muscles (vastus lateralis (VL) and vastus medialis (VM)) in humans. Twenty-one participants performed isometric knee extensions at 20 and 50% of maximal voluntary contractions (MVC). Myoelectric activity (surface electromyography (EMG)) provided an index of neural drive. Physiological cross-sectional area (PCSA) was estimated from measurements of muscle volume (magnetic resonance imaging) and muscle fascicle length (three-dimensional ultrasound imaging) to represent the muscles' force-generating capacities. Neither PCSA nor neural drive was balanced between VL and VM. There was a large (
r
= 0.68) and moderate (
r
= 0.43) correlation between the ratio of VL/VM EMG amplitude and the ratio of VL/VM PCSA at 20 and 50% of MVC, respectively. This study provides evidence that neural drive is biased by muscle force-generating capacity, the greater the force-generating capacity of VL compared with VM, the stronger bias of drive to the VL.
Phenotypic variability in unicellular organisms: from calcium signalling to social behaviour
Authors: Vogel David , Nicolis Stamatios C. , Perez-Escudero Alfonso , Nanjundiah Vidyanand , Sumpter David J. T. , Dussutour Audrey
Published: November 2015

Historically, research has focused on the mean and often neglected the variance. However, variability in nature is observable at all scales: among cells within an individual, among individuals within a population and among populations within a species. A fundamental quest in biology now is to find the mechanisms that underlie variability. Here, we investigated behavioural variability in a unique unicellular organism,
Physarum polycephalum
. We combined experiments and models to show that variability in cell signalling contributes to major differences in behaviour underpinning some aspects of social interactions. First, following thousands of cells under various contexts, we identified distinct behavioural phenotypes: ‘slow–regular–social’, ‘fast–regular–social’ and ‘fast–irregular–asocial’. Second, coupling chemical analysis and behavioural assays we found that calcium signalling is responsible for these behavioural phenotypes. Finally, we show that differences in signalling and behaviour led to alternative social strategies. Our results have considerable implications for our understanding of the emergence of variability in living organisms.
Similarity-based fusion of MEG and fMRI reveals spatio-temporal dynamics in human cortex during visual object recognition
Authors: Cichy Radoslaw Martin , Pantazis Dimitrios , Oliva Aude
Published: November 2015

Every human cognitive function, such as visual object recognition, is realized in a complex spatio-temporal activity pattern in the brain. Current brain imaging techniques in isolation cannot resolve the brain’s spatio-temporal dynamics because they provide either high spatial or temporal resolution but not both. To overcome this limitation, we developed a new integration approach that uses representational similarities to combine measurements from different imaging modalities – magnetoencephalography (MEG) and functional MRI (fMRI) - to yield a spatially and temporally integrated characterization of neuronal activation. Applying this approach to two independent MEG-fMRI data sets, we observed that neural activity first emerged in the occipital pole at 50-80ms, before spreading rapidly and progressively in the anterior direction along the ventral and dorsal visual streams. These results provide a novel and comprehensive, spatio-temporally resolved view of the rapid neural dynamics during the first few hundred milliseconds of object vision. They further demonstrate the feasibility of spatially unbiased representational similarity based fusion of MEG and fMRI, promising new insights into how the brain computes complex cognitive functions.
speciesgeocodeR: An R package for linking species occurrences, user-defined regions and phylogenetic trees for biogeography, ecology and evolution
Authors: Zizka Alexander , Antonelli Alexandre
Published: November 2015

1. Large-scale species occurrence data from geo-referenced observations and collected specimens are crucial for analyses in ecology, evolution and biogeography. Despite the rapidly growing availability of such data, their use in evolutionary analyses is often hampered by tedious manual classification of point occurrences into operational areas, leading to a lack of reproducibility and concerns regarding data quality.

2. Here we present speciesgeocodeR, a user-friendly R-package for data cleaning, data exploration and data visualization of species point occurrences using discrete operational areas, and linking them to analyses invoking phylogenetic trees.

3. The three core functions of the package are 1) automated and reproducible data cleaning, 2) rapid and reproducible classification of point occurrences into discrete operational areas in an adequate format for subsequent biogeographic analyses, and 3) a comprehensive summary and visualization of species distributions to explore large datasets and ensure data quality. In addition, speciesgeocodeR facilitates the access and analysis of publicly available species occurrence data, widely used operational areas and elevation ranges. Other functionalities include the implementation of minimum occurrence thresholds and the visualization of coexistence patterns and range sizes. SpeciesgeocodeR accompanies a richly illustrated and easy-to-follow tutorial and help functions.