bluuebunny/crossref_metadata_2025 huggingface dataset:
Cell chirality: its origin and roles in left–right asymmetric development
Authors: Inaki Mikiko , Liu Jingyang , Matsuno Kenji
Published: November 2016

An item is chiral if it cannot be superimposed on its mirror image. Most biological molecules are chiral. The homochirality of amino acids ensures that proteins are chiral, which is essential for their functions. Chirality also occurs at the whole-cell level, which was first studied mostly in ciliates, single-celled protozoans. Ciliates show chirality in their cortical structures, which is not determined by genetics, but by ‘cortical inheritance’. These studies suggested that molecular chirality directs whole-cell chirality. Intriguingly, chirality in cellular structures and functions is also found in metazoans. InDrosophila, intrinsic cell chirality is observed in various left–right (LR) asymmetric tissues, and appears to be responsible for their LR asymmetric morphogenesis. In other invertebrates, such as snails andCaenorhabditis elegans, blastomere chirality is responsible for subsequent LR asymmetric development. Various cultured cells of vertebrates also show intrinsic chirality in their cellular behaviours and intracellular structural dynamics. Thus, cell chirality may be a general property of eukaryotic cells. InDrosophila, cell chirality drives the LR asymmetric development of individual organs, without establishing the LR axis of the whole embryo. Considering that organ-intrinsic LR asymmetry is also reported in vertebrates, this mechanism may contribute to LR asymmetric development across phyla.

This article is part of the themed issue ‘Provocative questions in left–right asymmetry’.
Stochastic left–right neuronal asymmetry inCaenorhabditis elegans
Authors: Alqadah Amel , Hsieh Yi-Wen , Xiong Rui , Chuang Chiou-Fen
Published: November 2016

Left–right asymmetry in the nervous system is observed across species. Defects in left–right cerebral asymmetry are linked to several neurological diseases, but the molecular mechanisms underlying brain asymmetry in vertebrates are still not very well understood. TheCaenorhabditis elegansleft and right amphid wing ‘C’ (AWC) olfactory neurons communicate through intercellular calcium signalling in a transient embryonic gap junction neural network to specify two asymmetric subtypes, AWCOFF(default) and AWCON(induced), in a stochastic manner. Here, we highlight the molecular mechanisms that establish and maintain stochastic AWC asymmetry. As the components of the AWC asymmetry pathway are highly conserved, insights from the model organismC. elegansmay provide a window onto how brain asymmetry develops in humans.

This article is part of the themed issue ‘Provocative questions in left–right asymmetry’.
Embryonic chirality and the evolution of spiralian left–right asymmetries
Authors: Martín-Durán José M. , Vellutini Bruno C. , Hejnol Andreas
Published: November 2016

The group Spiralia includes species with one of the most significant cases of left–right asymmetries in animals: the coiling of the shell of gastropod molluscs (snails). In this animal group, an early event of embryonic chirality controlled by cytoskeleton dynamics and the subsequent differential activation of the genes
nodal
and
Pitx
determine the left–right axis of snails, and thus the direction of coiling of the shell. Despite progressive advances in our understanding of left–right axis specification in molluscs, little is known about left–right development in other spiralian taxa. Here, we identify and characterize the expression of
nodal
and
Pitx
orthologues in three different spiralian animals—the brachiopod
Novocrania anomala
, the annelid
Owenia fusiformis
and the nemertean
Lineus ruber
—and demonstrate embryonic chirality in the biradial-cleaving spiralian embryo of the bryozoan
Membranipora membranacea
. We show asymmetric expression of
nodal
and
Pitx
in the brachiopod and annelid, respectively, and symmetric expression of
Pitx
in the nemertean. Our findings indicate that early embryonic chirality is widespread and independent of the cleavage programme in the Spiralia. Additionally, our study illuminates the evolution of
nodal
and
Pitx
signalling by demonstrating embryonic asymmetric expression in lineages without obvious adult left–right asymmetries.

This article is part of the themed issue ‘Provocative questions in left–right asymmetry’.
Left–right analysis of mammary gland development in retinoid X receptor-α
+/−
mice
Authors: Robichaux Jacqulyne P. , Fuseler John W. , Patel Shrusti S. , Kubalak Steven W. , Hartstone-Rose Adam , Ramsdell Ann F.
Published: November 2016

Left–right (L–R) differences in mammographic parenchymal patterns are an early predictor of breast cancer risk; however, the basis for this asymmetry is unknown. Here, we use retinoid X receptor alpha heterozygous null (RXRα
+/−
) mice to propose a developmental origin: perturbation of coordinated anterior–posterior (A–P) and L–R axial body patterning. We hypothesized that by analogy to somitogenesis—in which retinoic acid (RA) attenuation causes anterior somite pairs to develop L–R asynchronously—that RA pathway perturbation would likewise result in asymmetric mammary development. To test this, mammary glands of RXRα
+/−
mice were quantitatively assessed to compare left- versus right-side ductal epithelial networks. Unlike wild-type controls, half of the RXRα
+/−
thoracic mammary gland (TMG) pairs exhibited significant L–R asymmetry, with left-side reduction in network size. In RXRα
+/−
TMGs in which symmetry was maintained, networks had bilaterally increased size, with left networks showing greater variability in area and pattern. Reminiscent of posterior somites, whose bilateral symmetry is refractory to RA attenuation, inguinal mammary glands (IMGs) also had bilaterally increased network size, but no loss of symmetry. Together, these results demonstrate that mammary glands exhibit differential A–P sensitivity to RXRα heterozygosity, with ductal network symmetry markedly compromised in anterior but not posterior glands. As TMGs more closely model human breast development than IMGs, these findings raise the possibility that for some women, breast cancer risk may initiate with subtle axial patterning defects that result in L–R asymmetric growth and pattern of the mammary ductal epithelium.

This article is part of the themed issue ‘Provocative questions in left–right asymmetry’.
A unified encyclopedia of human functional DNA elements through fully automated annotation of 164 human cell types
Authors: Libbrecht Maxwell W. , Rodriguez Oscar , Weng Zhiping , Bilmes Jeffrey A. , Hoffman Michael M. , Noble William S.
Published: November 2016

Semi-automated genome annotation methods such as Segway enable understanding of chromatin activity. Here we present chromatin state annotations of 164 human cell types using 1,615 genomics data sets. To produce these annotations, we developed a fully-automated annotation strategy in which we train separate unsupervised annotation models on each cell type and use a machine learning classifier to automate the state interpretation step. Using these annotations, we developed a measure of the importance of each genomic position called the “conservation-associated activity score,” which we use to aggregate information across cell types into a multi-cell type view. The aggregated conservation-associated activity score provides a measure of importance directly attributable to a specific activity in a specific set of cell types. In contrast to evolutionary conservation, this measure is not biased to detect only elements shared with related species. Using the conservation-associated activity score, we combined all our annotations into a single, cell type-agnostic encyclopedia that catalogs all human transcriptional and regulatory elements, enabling easy and intuitive interpretation of the effect of genome variants on phenotype, such as in disease-associated, evolutionarily conserved or positively selected loci. These resources, including cell type-specific annotations, encyclopedia, and a visualization server, are available athttp://noble.gs.washington.edu/proj/encyclopedia.

Author Summary

Genome annotation algorithms are an effective class of tools for understanding the function of the genome. These algorithms take as input a set of genome-wide measurements about the activity at each base pair in a given tissue, such as where a given protein is binding or how accessible the DNA is to being read by a protein. The genome is then partitioned and each segment is assigned a label such that positions with the same label exhibit similar patterns in the input data. Such annotations are widely used for many applications, such as to understand the mechanism of impact of a given genetic variant. Here we present, to our knowledge, the most comprehensive set of genome annotations created so far, encompassing 164 human cell types and including 1,615 genomics data sets. These comprehensive annotations are made possible by a strategy that automates the previous interpretation step. Furthermore, we present several methodological innovations that make these genome annotations more useful.
Beyond excitation/inhibition imbalance in multidimensional models of neural circuit changes in brain disorders
Authors: O’Donnell Cian , Tiago Gonçalves J. , Portera-Cailliau Carlos , Sejnowski Terrence J.
Published: November 2016

A leading theory holds that neurodevelopmental brain disorders arise from imbalances in excitatory and inhibitory (E/I) brain circuitry. However, it is unclear whether this onedimensional model is rich enough to capture the multiple neural circuit alterations underlying brain disorders. Here we combined computational simulations with analysis ofin vivo2-photon Ca2+imaging data from somatosensory cortex ofFmr1knock-out (KO) mice, a model of Fragile-X Syndrome, to test the E/I imbalance theory. We found that: 1) The E/I imbalance model cannot account for joint alterations in the observed neural firing rates and correlations; 2) Neural circuit function is vastly more sensitive to changes in some cellular components over others; 3) The direction of circuit alterations inFmr1KO mice changes across development. These findings suggest that the basic E/I imbalance model should be updated to higher-dimensional models that can better capture the multidimensional computational functions of neural circuits.
Application of PSO algorithm to choose the best scenario for energy demand forecast of residential and commercial sectors in Iran
Authors: Nazari Hesam , Kazemi Aliyeh
Published: November 2016

Purpose

This paper aims to select the best scenario for energy demand forecast of residential and commercial sectors in Iran by using particle swarm optimization algorithm.

Design/methodology/approach

In this study, using variables affecting energy demand of residential and commercial sectors in Iran, the future status of energy demand in these sectors is predicted. Using the particle swarm optimization algorithm, both linear and exponential forms of energy demand equations were studied under 72 different scenarios with various variables. The data from 1968 to 2011 were applied for model development and the appropriate scenario choice.

Findings

An exponential model with inputs including total value added minus that of the oil sector, value of made buildings, total number of households and consumer energy price index is the most suitable model. Finally, energy demand of residential and commercial sectors is estimated up to the year 2032. Results show that the energy demand of the sectors will achieve a level of about 1,718 million barrels of oil equivalent per year by 2032.

Originality/value

To the best of our knowledge in this study a suitable model is selected for energy demand forecast of residential and commercial sectors by evaluation of various models with different variables as inputs.
Impact of crime on spatial analysis of house prices: evidence from a UK city
Authors: McIlhatton David , McGreal William , Taltavul de la Paz Paloma , Adair Alastair
Published: November 2016

Purpose

There is a lack of understanding in the literature on the spatial relationships between crime and house price. This paper aims to test the impact of spatial effects in the housing market, how these are related to the incidence of crime and whether effects vary by the type of crime.

Design/methodology/approach

The analysis initially explores univariate and bivariate spatial patterns in crime and house price data for the Belfast Metropolitan Area using Moran’s I and Local Indicator Spatial Association (LISA) models, and secondly uses spatial autoregression models to estimate the role of crime on house prices. A spatially weighted two-stage least-squares model is specified to analyse the joint impact of crime variables. The analysis is cross sectional, based on a panel of data.

Findings

The paper illustrates that the pricing impact of crime is complex and varies by type of crime, property type and location. It is shown that burglary and theft are associated with higher-income neighbourhoods, whereas violence against persons, criminal damage and drugs offences are mainly associated with lower-priced neighbourhoods. Spatial error effects are reduced in models based on specific crime variables.

Originality/value

The originality of this paper is the application of spatial analysis in the study of the impact of crime upon house prices. Criticisms of hedonic price models are based on unexplained error effects; the significance of this paper is the reduction of spatial error effects achievable through the analysis of crime data.
The impact of residential development on nearby housing prices
Authors: Kurvinen Antti Tapio , Vihola Jaakko
Published: November 2016

Purpose

Even as multi-story apartment building development proposals in existing neighbourhoods represent a substantial component of policy debate at local planning boards, there is limited evidence for the impact of such residential developments on surrounding apartment values. This paper aims to address the void in knowledge, and the impact of multi-story apartment building developments on apartment values in residential high-rise areas located outside city and district centres is investigated in Helsinki Metropolitan Area, Finland.

Design/methodology/approach

Whether a multi-story apartment building development is followed by an increase in housing values depends on both positive and negative externalities. To specify valuation effects of proximate development projects, advanced research design combining matched sample methodology and hedonic-based difference-in-difference approach is used.

Findings

It appears from the analysis that completion of a single multi-story apartment building has an immediate positive impact on apartment values within 300 metre radius, while there is no statistically significant impact on price trend.

Research limitations/implications

This paper studies apartment values only in Helsinki Metropolitan Area, Finland, and it is important to notice that local regulations and market conditions may have a notable impact on the outcomes.

Originality/value

This study is the first of its kind to provide with statistically significant evidence for positive impacts from multi-story apartment building development in Finnish residential high-rise areas and may have a crucial role in helping to dispel prejudices related to such developments.
The quantitative easing effect on the stock market of the USA, the UK and Japan
Authors: Lima Luiz , Vasconcelos Claudio Foffano , Simão Jose , de Mendonça Helder Ferreira
Published: November 2016

Purpose

The purpose of this paper is to analyze if the unconventional monetary policy, known as quantitative easing (QE) practiced by central banks in the USA, the UK, and Japan was effective to increase the market share after subprime crisis.

Design/methodology/approach

In order to analyze the effect of the QE on the stock markets of the USA, the UK, and Japan, the authors use an ARDL model to find the long-run relationship among the variables.

Findings

The findings denote that the QE implemented by the central banks in the USA, Japan, and the UK had a positive impact on their stock markets.

Originality/value

The results of the paper give some new insights about the conduction of monetary policy when the interest rates are close to zero.
Diversity and competition influence tree allometric relationships – developing functions for mixed‐species forests
Authors: Forrester David Ian , Benneter Adam , Bouriaud Olivier , Bauhus Jürgen
Published: November 2016

Promoting mixed‐species forests is an important strategy for adaptation and risk reduction in the face of global change. Concurrently, a main challenge in ecology is to quantify the effects of species diversity on ecosystem functioning. In forests, the effects of individual tree species on ecosystem functions depend largely on their dimensions, which are commonly predicted using allometric equations. However, little is known about how diversity influences allometry or how to incorporate this effect into allometric equations. Ignoring the effects of interspecific interactions on allometric relationships may result in severely biased predictions.

This study examined the effects of tree‐species diversity, competition and tree social status on crown‐projection area (cpa), height (h) and live‐crown length (lcl) of trees using a European‐wide data set containing 17 target species and 12 939 trees. The cpa, h and lcl were predicted as functions of stem diameter at 1·3 m, tree‐species diversity, tree height relative to the stand mean height (rh) and a competition index (CI) that accounted for stand density and interspecific differences in competitive ability based on species‐specific wood density or shade tolerance.

Averaged across species, diameter had the greatest effect on cpa and lcl, followed by the competition index, while rh had the greatest effect on lcl. Tree‐species diversity had the smallest effect on cpa, h and lcl. Interspecific variability in cpa, h or lcl responses to diversity, CI, or rh was sometimes related to wood density or shade tolerance.

Synthesis. This study shows the strong influence of stand structure and species composition on allometric relationships. These influences can be quantified using measures of competition, tree‐species diversity and relative tree height so that general equations can be developed for a given species to be applied to a wide range of species compositions and stand structures. This new approach will greatly improve predictions of biomass and carbon stocks in structurally and compositionally diverse forests.
An evolutionary game theoretical model shows the limitations of the additive partitioning method for interpreting biodiversity experiments
Authors: Vermeulen Peter J. , van Ruijven Jasper , Anten Niels P. R. , van der Werf Wopke
Published: November 2016

The relationship between diversity and ecosystem functioning is often analysed by partitioning the change in species performance in mixtures into a complementarity effect (CE) and a selection effect (SE). There is continuing ambiguity in the literature on the interpretation of these effects, mainly in their relationship to ecological mechanisms and processes.

Here, we present the emergence of complementarity and selection effects in the results of an evolutionary game theoretical model for plant competition which is exclusively based on competition for light. Eight plant strategies, differing only in the time of onset of flowering, were played against one another to determine the relationship between plant trait differences and CE vs. SE.

We show that competitive exclusion may occur even in the presence of a positive CE, i.e. when CE > 0. CE was highest at intermediate differences in flowering time. Increasing trait differences may, therefore, increase CE without leading to coexistence.

SE was strongly dependent on which of the strategies was paired. SE was mostly positive if one of the players was early flowering (with low seed yield) and the other strategy had higher monoculture yields. SE was mostly negative if one of the players was late flowering, leading to low monoculture yield for this strategy, but to high gains when competing with strategies that produce less leaf area. The average SE was negative over all pairs.

Synthesis. These results show that CE may be positive if the species interaction is beneficial for only one of the two competitors, and the sign of SE depends critically on the underlying mechanism for performance in monoculture. Positive complementarity may go hand in hand with competitive exclusion, while widely different outcomes in SE are possible within a single mechanistic background. Consequently, the way SE changes with increasing richness are not only related to a sampling/selection effect but also by the way the interacting species affect the competitive environment. Interpreting the additive partitioning method with a set notion in mind about the driving mechanisms could lead to incorrect conclusions on how species richness effects drive ecosystem functioning.
Phenotypic variation in food utilization in an outbreak insect herbivore
Authors: Quezada‐García Roberto , Fuentealba Álvaro , Bauce Éric
Published: November 2016

The effects of nutrition may have subtantial impact on insect evolution by shaping different components of phenotypes. The key to undestanding this evolutionary process is to know how nutritional condition affects additive and nonadditive components of the phenotype. However, this is poorly understood in outbreaking insects. We investigated the additive and nonadditive variation present in food utilization traits in spruce budworm individuals subjected to chronic nutritional stress. A total of 160 full‐sib families of spruce budworm (Choristoneura fumiferana Clem.) were raised under laboratory conditions, feeding on 2 diets (high and low energy) during 3 generations. Variables tested were pupal mass, consumption rate (RCR), growth rate (RGR), approximate digestibility (AD), the efficiency of conversion of digested food (ECD) and the efficiency of conversion of ingested food (ECI). Our results show that all traits tested presented a high percentage of nonadditive effects that modulate phenotype expression. We found a significant impact of family × diet interaction on pupal mass, RGR and ECD. Furthermore, these traits exhibited the greatest heritability. There was no evidence of presence of maternal effects. The results revealed that food utilization traits may evolve through epigenetics effects, such as phenotypic plasticity. This information can be used by modellers to improve forecast of spruce budworm population dynamics.
Decomposing functional diversity
Authors: Scheiner Samuel M. , Kosman Evsey , Presley Steven J. , Willig Michael R.
Published: November 2016

One aspect of biodiversity, functional diversity, reflects the functional role of species within a community as measured by species characteristics. We present a new metric, functional trait dispersion, based on the concept of species distinctiveness measured as the distance among species in the multidimensional space defined by trait values. This metric can be decomposed into components of species richness, functional evenness and mean dispersion, and into parts that measure diversity within and among subgroups.

Using an appropriate distance measure, mean dispersion (M′) is calculated as the average distance among all possible pairs of species. Functional evenness [qE(T)] is derived from Hill diversity based on the proportional distances between pairs of species and species richness (S). Functional trait dispersion [qD(TM)] is then computed as 1 + (S−1) × qE(T) × M′. It has a range of [1,S] and measures the effective number of functionally distinct species for a given level of species dispersion.

Using constructed data, we demonstrate that qD(TM) captures appropriate ecological properties such that a community with greater species richness, greater dispersal in trait space or greater mean dispersion has greater functional diversity. Functional trait dispersion can also provide measures of within‐community dispersion and the effective number of functionally distinctive compartments (groups of communities with similar functional structure). Using empirical data of bats along an elevational gradient in Peru, we demonstrate that functional trait dispersion and its components provide insights about gradients of biodiversity.

Functional trait dispersion comports to reasonable criteria for a metric of functional diversity and can be decomposed in a variety of ways that facilitate understanding of patterns of variation. Other metrics of functional diversity neither integrate all three diversity components, nor can many be decomposed into variation within and among subgroups. Because functional trait dispersion measures properties of distance and the effective number of functionally distinct species, it can be used in conjunction with other biodiversity metrics that are based on species identity, abundance or phylogenetic relatedness to inform management and the preservation of biodiversity.
Monitoring of plant–environment interactions by high‐throughput FTIR spectroscopy of pollen
Authors: Bağcıoğlu Murat , Kohler Achim , Seifert Stephan , Kneipp Janina , Zimmermann Boris
Published: November 2016

Fourier transform infrared (FTIR) spectroscopy enables chemical analysis of pollen samples for plant phenotyping to study plant–environment interactions, such as influence of climate change or pathogens. However, current approach, such as microspectroscopy and attenuated total reflection spectroscopy, does not allow for high‐throughput protocols. This study at hand suggests a new spectroscopic method for high‐throughput characterization of pollen.

Samples were measured as thin films of pollen fragments using a Bruker FTIR spectrometer with a high‐throughput eXTension (HTS‐XT) unit employing 384‐well plates. In total, 146 pollen samples, belonging to 31 different pollen species of Fagaceae and Betulaceae and collected during three consecutive years (2012–2014) at locations in Croatia, Germany and Norway, were analysed. Critical steps in the sample preparation and measurement, such as variabilities between technical replicates, between microplates and between spectrometers, were studied.

Measurement variations due to sample preparation, microplate holders and instrumentation were low, and thus allowed differentiation of samples with respect to phylogeny and biogeography. The spectral variability for a range of Fagales species (Fagus, Quercus, Betula, Corylus, Alnus and Ostrya) showed high‐species‐specific differences in pollen's chemical composition due to either location or year. Statistically significant inter‐annual and locational differences in the pollen spectra indicate that pollen chemical composition has high phenotypic plasticity and is influenced by local climate conditions. The variations in composition are connected to lipids, proteins, carbohydrates and sporopollenins that play crucial roles in cold and desiccation tolerance, protection against UV radiation and as material and energy reserves.

The results of this study demonstrate the value of high‐throughput FTIR approach for the systematic collection of data on ecosystems. The novel FTIR approach offers fast, reliable and economical screening of large number of samples by semi‐automated methodology. The high‐throughput approach could provide crucial understanding on plant–climate interactions with respect to biochemical variation within genera, species and populations.
Quantitative ornithology with a commercial marine radar: standard‐target calibration, target detection and tracking, and measurement of echoes from individuals and flocks
Authors: Urmy Samuel S. , Warren Joseph D.
Published: November 2016

Marine surveillance radars are commonly used for radar ornithology, but they are rarely calibrated. This prevents them from measuring the radar cross‐sections (RCS) of the birds under study. Furthermore, if the birds are aggregated too closely for the radar to resolve them individually, the bulk volume reflectivity cannot be translated into a numerical density.

We calibrated a commercial off‐the‐shelf marine radar, using a standard spherical target of known RCS. Once calibrated, the radar was used to measure the RCS of common and roseate terns (Sterna hirundo L. and Sterna dougallii Montagu) tracked from a land‐based installation at their breeding colony on Great Gull Island, NY, USA. We also integrated echoes from flocks of terns, comparing these total flock cross‐sections with visual counts from photos taken at the same time as the radar measurements.

The radar's calibration parameters were determined with 1% error. RCS measurements made after calibration were expected to be accurate within ±2 dB. Mean tern RCS was estimated at −28 dB relative to one square meter (dBsm), agreeing in magnitude with a simple theoretical model. RCS was 3–4 dB higher when birds’ aspect angles were broadside to the radar beam compared with head‐ or tail‐on. Integrated flock cross‐section was linearly related to the number of birds. The slope of this line, an independent estimate of RCS, was −32 dBsm, within an order of magnitude of the estimate from individual birds, and near the middle of the frequency distribution of RCS values.

These results indicate that a calibrated marine radar can count the birds in an aggregation via echo integration. Field calibration of marine radars is practical, enables useful measurements, and should be done more often.
Discarded Livers Find a New Life: Engineered Liver Grafts Using Hepatocytes Recovered From Marginal Livers
Authors: Uygun Basak E. , Izamis Maria‐Louisa , Jaramillo Maria , Chen Yibin , Price Gavrielle , Ozer Sinan , Yarmush Martin L.
Published: November 2016

Treatment for end‐stage liver failure is restricted by the critical shortage of donor organs; about 4000 people die in the USA while waiting for a transplantable organ. This situation has been a major driving force behind the rise of tissue engineering to build artificial tissues/organs. Recent advancements in creating transplantable liver grafts using decellularized liver scaffolds bring the field closer to clinical translation. However, a source of readily available and highly functional adult hepatocytes in adequate numbers for regenerative liver therapies still remains unclear. Here, we describe a new method to utilize discarded livers to make transplantable new liver grafts. We show that marginal donor livers damaged due to warm ischemia could be treated with machine perfusion to yield 39 million viable hepatocytes per gram of liver, similar to fresh livers, and these cells could be used to repopulate decellularized liver matrix (DLM) scaffolds to make transplantable liver grafts. The hepatocytes from recovered livers sustained their characteristic epithelial morphology while they exhibited slightly lower protein synthesis functions both in plate cultures and in recellularized liver grafts. The dampened protein synthesis was attributed to residual endoplasmic reticulum stress found in recovered cells. The results here represent a unique approach to reengineer transplantable liver grafts solely from discarded organs.
Postoperative Ambulatory Performance Status Significantly Affects Implant Failure Rate Among Surgical Treatment Strategies in Patients With Proximal Femur Metastasis
Authors: Tsai Shang‐Wen , Wu Po‐Kuei , Chen Cheng‐Fong , Chang Ming‐Chau , Chen Wei‐Ming
Published: November 2016

Surgical treatment strategies for proximal femur metastasis have been reported with mixed results. Little is known about risk factor for implant failure except for longer patient survival. Therefore, we determined whether implant survivorship differed among treatment strategies, as well as risk factors for implant failure. We retrospectively reviewed a consecutive 106 patients with proximal femur metastasis treated with prosthesis replacement (n = 38), intramedullary nail (n = 32), and dynamic hip screw (DHS) (n = 36). Eastern Cooperative Oncology Group (ECOG) scale and Karnofsky index were used to evaluate functional outcome. Patient characteristics and postoperative ambulatory performance status were assessed for their values in determining implant failure. Overall implant failure rate was 11.3% (12 of 106). Prosthesis replacement was related to better implant survivorship (P = 0.041), without mechanical failures. On the contrary, 7 of the 10 implant failures in the fixation group were considered mechanical failures. Better postoperative ambulatory status (ECOG ≤ 2) was a risk factor for implant failure (P = 0.03). Notably, for patients with poor ambulatory status (ECOG ≥ 3), implant survivorship was not different among choice of implants. In conclusion, prosthesis replacement would be a more durable option in the treatment of proximal femur metastasis. Postoperative ambulatory status could be an additional consideration. For patients with poor expected ambulatory performance status, fixation with intramedullary nail or DHS might be considered for a less technical demanding procedure.
Predictors of adequate ultrasound quality for hepatocellular carcinoma surveillance in patients with cirrhosis
Authors: Simmons O. , Fetzer D. T. , Yokoo T. , Marrero J. A. , Yopp A. , Kono Y. , Parikh N. D. , Browning T. , Singal A. G.
Published: November 2016

Background

Abdominal ultrasound fails to detect over one‐fourth of hepatocellular carcinoma (HCC) at an early stage in patients with cirrhosis. Identifying patients in whom ultrasound is of inadequate quality can inform interventions to improve surveillance effectiveness.

Aim

To evaluate and identify predictors of ultrasound quality in patients with cirrhosis.

Methods

We performed a retrospective cohort study among patients who underwent ultrasound examination for a cirrhosis‐related indication between April 2015 and October 2015. Three fellowship‐trained abdominal radiologists collectively reviewed all ultrasound exams and categorised exam quality as definitely adequate, likely adequate, likely inadequate and definitely inadequate to exclude liver lesions. We performed multivariable logistic regression to determine characteristics associated with inadequate ultrasound quality.

Results

Among 941 patients, 191 (20.3%) ultrasounds were inadequate for excluding HCC‐ 134 definitely inadequate and 57 likely inadequate. In multivariable analysis, inadequate quality was associated with male gender (OR 1.68, 95% CI 1.14–2.48), body mass index category (OR 1.67, 95% CI 1.45–1.93), Child–Pugh B or C cirrhosis (OR 1.93, 95% CI 1.32–2.81), alcohol‐related cirrhosis (OR 2.11, 95% CI 1.33–3.37), NASH cirrhosis (OR 2.87, 95% CI 1.71–4.80), and in‐patient status (OR 1.55, 95% CI 1.01–2.37). Ultrasounds were inadequate in over one‐third of patients with Child–Pugh C cirrhosis, BMI >35, or NASH cirrhosis.

Conclusions

One in five ultrasounds in patients with cirrhosis are inadequate for exclusion of HCC, which can contribute to surveillance failure. Alternative surveillance modalities are needed in subgroups prone to inadequate ultrasounds including obese patients, those with Child Pugh B or C cirrhosis, and those with alcohol‐ or NASH‐related cirrhosis.
The Exemplary Citizen on the Exemplary Hill: The Production of Political Subjects in Contemporary Rural Rwanda
Authors: Ansoms An , Cioffo Giuseppe D.
Published: November 2016

Since the end of civil war and genocide in 1994, the Rwandan government has embarked on an ambitious plan to reshape the rural setting. Through a strategy of agrarian modernization, the Rwandan government is reorganizing rural space and production in order to foster economic growth. This article looks at how this spatial and productive reconfiguration contributes to the production of political subjects in post‐genocide Rwanda, and how this is constitutive of the political power of government. First, it points to the way in which the state authorities’ discursive practices utilize the concept of ‘exemplary citizenship’ to reinforce policy adherence. Second, it analyses how the reconfiguration of access to productive resources is intertwined with the reinforcement of the state's authority. Hidden behind the discourse of modernization and rationalization, the reorganization of space helps central authorities to gain a greater degree of control over rural settings. Finally, it analyses the way in which the reorganization of rural space contributes to the construction of political subjectivity. Political subjects are defined through adherence to or rejection of the government's rhetoric of economic development and good citizenship as redefining moments of public life.
Taxation, Stateness and Armed Groups: Public Authority and Resource Extraction in Eastern Congo
Authors: Hoffmann Kasper , Vlassenroot Koen , Marchais Gauthier
Published: November 2016

This contribution analyses the role of taxation in the constitution of authority in the conflict‐ridden eastern Democratic Republic of the Congo, where a multitude of authorities alternately compete and collude over the right to extract resources. Taxation ranges from simple plunder, to protection rackets, to the material reciprocation of the recognition of rights. Focusing on the taxation practices of armed groups, the article argues that taxation is at the core of armed groups’ production of public authority and citizenship, and that their modes of taxation are based on long‐standing registers of authority and practices of rule that originate in the colonial era. In particular, the article shows that by appealing to both local customary and national forms of political community and citizenship, armed groups are able to assume public authority to tax civilians. However, their public authority may be undermined by their tendency to reproduce a historical pattern in which authorities forcefully impose a heavy tax burden, while providing limited public goods and services in return.
Genetic admixture and heterosis may enhance the invasiveness of common ragweed
Authors: Hahn Min A. , Rieseberg Loren H.
Published: November 2016

Biological invasions are often associated with multiple introductions and genetic admixture of previously isolated populations. In addition to enhanced evolutionary potential through increased genetic variation, admixed genotypes may benefit from heterosis, which could contribute to their increased performance and invasiveness. To deepen our understanding of the mechanisms and management strategies for biological invasions, we experimentally studied whether intraspecific admixture causes heterosis in common ragweed (Ambrosia artemisiifolia) by comparing the performance of crosses (F1) between populations relative to crosses within these populations for each range (native, introduced) under different ecologically relevant conditions (control, drought, competition, simulated herbivory). Performance of admixed genotypes was highly variable, ranging from strong heterotic effects to weak outbreeding depression. Moreover, heterosis was not uniformly observed among between‐population crosses, but certain native population crosses showed considerable heterosis, especially under simulated herbivory. In contrast, heterosis was largely absent in crosses from the introduced range, possibly implying that these populations were already admixed and benefit little from further mixing. In conclusion, these results support the hypothesis that heterosis may contribute to biological invasions, and indicate the need to minimize new introductions of exotic species, even if they are already present in the introduced range.
An integrated method for real time and offline web robot detection
Authors: Doran Derek , Gokhale Swapna S.
Published: November 2016

Recent academic and industry reports confirm that web robots dominate the traffic seen by web servers across the Internet. Because web robots crawl in an unregulated fashion, they may threaten the privacy, function, performance, and security of web servers. There is therefore a growing need to be able to identify robot visitors automatically, in offline and in real time, to assess their impact and to potentially protect web servers from abusive bots. Yet contemporary detection approaches, which rely on syntactic log analysis, finding statistical variations between robot and human traffic, analytical learning techniques, or complex software modifications may not be realistic to implement or remain effective as the behavior of robots evolve over time. Instead, this paper presents a novel detection approach that relies on the differences in the resource request patterns of web robots and humans. It rationalizes why differences in resource request patterns are expected to remain intrinsic to robots and humans despite the continuous evolution of their traffic. The performance of the approach, adoptable for both offline and real time settings with a simple implementation, is demonstrated by playing back streams of actual web traffic with varying session lengths and proportions of robot requests.
What Did You Say? How Did You Say It? Linguistics Choices in Online Discussions
Authors: Oskoz Ana , Pérez‐Broncano Olimpia
Published: November 2016

Following appraisal theory (Martin & White, 2005), which examines the linguistic resources through which texts/speakers express, negotiate, and naturalize particular intersubjective or ideological positions (White, 2015), this study addresses (1) the extent to which second language (L2) learners express their attitudes toward their own and the L2 culture, and (2) the stance L2 learners take when addressing values and behaviors associated with both cultures. Analysis of the linguistic choices of L2 learners in a fourth‐year Spanish language class's online discussions revealed that the learners’ views and attitudes toward their own culture were somewhat negative, whereas their orientations in relation to the L2 culture were positively skewed. The analysis also illustrated how learners engage or disengage with their own statements and negotiate their ideological positions where the first and second cultures are concerned. Despite certain limitations and a need for further research, this study suggests that appraisal theory can provide insightful and exciting information about L2 learners’ attitudes and ideological positioning with regard to first and second cultures, indicating, therefore, that appraisal theory presents itself as a different, complementary approach to research L2 learners’ cultural discussions.
A loss of profilin‐1 in late‐stage oral squamous cell carcinoma
Authors: Adami Guy R. , O'Callaghan Thomas N. , Kolokythas Antonia , Cabay Robert. J. , Zhou Yalu , Schwartz Joel L.
Published: November 2016

Background

The genes for PFN1 and TMSB4 are both highly expressed in oral tissue and both encode actin monomer binding proteins thought to play a role in cell motility and possibly other crucial parts of tumor progression.

Methods

Oral brush cytology of epithelium from oral squamous cell carcinoma (OSCC) was used to measure PFN1 and TMSB4 mRNA in OSCC, while immunohistochemical analysis of tissue was used to check protein levels.

Results

High but variable expression of mRNAs encoding these two proteins was observed suggesting they may contribute to tumor characteristics in a subset of OSCCs. Both proteins were highly expressed in normal appearing basal epithelium, in the cytoplasm, and perinuclear area, while expression was minimal in upper epithelial layers. In OSCCs, expression of these proteins varied. In tumors classified as later stage, based on size and/or lymph node involvement, PFN1 levels were lower in tumor epithelium. A control gene, KRT13, showed expression in normal differentiated basal and suprabasal oral mucosa epithelial cells and as reported was lost in OSCC cells.

Conclusion

Loss of PFN1 in tumor cells has been associated with lymph node invasion and metastasis in other tumor types, strengthening the argument that the protein has the potential to be a tumor suppressor in late‐stage OSCC.
Effects of spatiotemporal heterogeneity of forage availability on annual range size of Mongolian gazelles
Authors: Imai S. , Ito T. Y. , Kinugasa T. , Shinoda M. , Tsunekawa A. , Lhagvasuren B.
Published: November 2016

We analyzed the effects of forage amount and its spatiotemporal heterogeneity on the annual range size of Mongolian gazelles by tracking 20 gazelles over a wide range of their distribution in Mongolia and by applying the normalized difference vegetation index (NDVI). Annual ranges were separated into four regions. The maximum individual annual range size was more than 40 times the minimum (range: 900–37 000 km2). Annual range size was increased with increasing forage amount and spatial heterogeneity and seasonal change in forage amount. Many tracked gazelles changed their range locations between summer and winter, and these ranges occupied only small parts of their annual ranges. The smaller annual range size in the areas with smaller forage amount was explained by the smaller seasonal change and spatial heterogeneity of forage amount. Knowledge of such variations of movements and environments in a continuous distribution can improve our understanding of movement ecology.
Inbreeding avoidance and female mate choice shape reproductive skew in capuchin monkeys (Cebus capucinus imitator)
Authors: Wikberg Eva C. , Jack Katharine M. , Fedigan Linda M. , Campos Fernando A. , Yashima Akiko S. , Bergstrom Mackenzie L. , Hiwatashi Tomohide , Kawamura Shoji
Published: November 2016

Reproductive skew in multimale groups may be determined by the need for alpha males to offer reproductive opportunities as staying incentives to subordinate males (concessions), by the relative fighting ability of the alpha male (tug‐of‐war) or by how easily females can be monopolized (priority‐of‐access). These models have rarely been investigated in species with exceptionally long male tenures, such as white‐faced capuchins, where female mate choice for novel unrelated males may be important in shaping reproductive skew. We investigated reproductive skew in white‐faced capuchins at Sector Santa Rosa, Costa Rica, using 20 years of demographic, behavioural and genetic data. Infant survival and alpha male reproductive success were highest in small multimale groups, which suggests that the presence of subordinate males can be beneficial to the alpha male, in line with the concession model's assumptions. None of the skew models predicted the observed degree of reproductive sharing, and the probability of an alpha male producing offspring was not affected by his relatedness to subordinate males, whether he resided with older subordinate males, whether he was prime aged, the number of males or females in the group or the number of infants conceived within the same month. Instead, the alpha male's probability of producing offspring decreased when he was the sire of the mother, was weak and lacked a well‐established position and had a longer tenure. Because our data best supported the inbreeding avoidance hypothesis and female choice for strong novel mates, these hypotheses should be taken into account in future skew models.
Feminist Jewish Thought as Postliberal Theology
Authors: Farneth Molly
Published: November 2016

This essay considers feminist Jewish thought as a contribution to postliberal theology, insofar as it shares postliberal theology's emphasis on the sociality of reason and of revelation. In particular, the essay focuses on the authority of halakhah, or Jewish law, in the work of Judith Plaskow, Rachel Adler, and Tamar Ross, and it highlights the way that each “goes social” in her account of that authority. Like other forms of postliberal theology, feminist Jewish thought tends to emphasize the relationships and social practices that constitute a form of life and which make norms and laws authoritative for the people who participate in that form of life. Then, the essay turns to the ethical implications of those relationships and social practices, through an analysis of Plaskow and Adler's accounts of authority in human and human‐divine relations. For each of these figures, given the sociality of reason and revelation, relationships among knowers ought to be characterized by reciprocal recognition and accountability.