bluuebunny/crossref_metadata_2025 huggingface dataset:
Tropical bat as mammalian model for skin carotenoid metabolism
Authors: Galván Ismael , Garrido-Fernández Juan , Ríos José , Pérez-Gálvez Antonio , Rodríguez-Herrera Bernal , Negro Juan José
Published: September 2016

Significance

We have discovered that a mammalian species, a bat called the Honduran white bat
Ectophylla alba
, displays a yellow carotenoid pigment called lutein in its bare skin. Even though carotenoid-based coloration has been found in birds, fish, amphibians, and reptiles, there are no reports of any extant mammals showing these pigments in their skin or hair. The implications of this finding may be profound for human health, as carotenoids are essential micronutrients. Lutein in particular is involved in the preservation of the macula of the eye. The Honduran white bat, with its ability to assimilate and deposit lutein in its bare skin, may be the sought-after mammalian model needed for enhancing studies on carotenoid function and metabolism.
SPRY1 regulates mammary epithelial morphogenesis by modulating EGFR-dependent stromal paracrine signaling and ECM remodeling
Authors: Koledova Zuzana , Zhang Xiaohong , Streuli Charles , Clarke Robert B. , Klein Ophir D. , Werb Zena , Lu Pengfei
Published: September 2016

Significance

Despite its importance in epithelial development and in breast cancer, the role of EGF receptor (EGFR) signaling and its regulation in the postnatal mammary stroma has remained unclear. Here, we show that sprouty 1 (
Spry1
) modulates epithelial–stromal interactions by inhibiting EGFR-dependent stromal paracrine signaling and ECM remodeling.
Spry1
loss leads to upregulated EGFR signaling and enhanced stromal activities, including ECM remodeling and growth factor production, and ultimately increased epithelial branching. By contrast, EGFR signaling reduction in fibroblasts leads to stunted epithelial branching. We show that EGFR and FGF receptor (FGFR) signaling constitute a critical part of stromal–epithelial interactions during postnatal development and that these signaling pathways are fine-tuned by different members of the
Sprouty
gene family to ensure normal epithelial morphogenesis of the mammary gland.
Regulation of the thermoalkaliphilic F
1
-ATPase from
Caldalkalibacillus thermarum
Authors: Ferguson Scott A. , Cook Gregory M. , Montgomery Martin G. , Leslie Andrew G. W. , Walker John E.
Published: September 2016

Significance

Adenosine triphosphate (ATP), the fuel of life, is produced by a molecular machine consisting of two motors linked by a rotor. One generates rotation by consuming energy derived from oxidative metabolism or photosynthesis; the other uses energy transmitted by the rotor to put ATP molecules together from their building blocks adenosine diphosphate and phosphate. In many species the machine is easily reversible, and various different mechanisms to regulate the reverse action have evolved so that it is used only when needed. In some eubacterial species, including the thermoalkaliphile
Caldalkalibacillus thermarum
, although evidently constructed in a similar way to reversible machines, the reverse action is severely impeded, evidently because the products of hydrolysis remain bound to the machine.
Follow-up and evaluation of the pregnancy outcome in women of reproductive age with Graves’ disease after 131Iodine treatment
Authors: Zhang Li-Hua , Li Jing-Yan , Tian Qi , Liu Shuang , Zhang Hong , Liu Sheng , Liang Jiu-Gen , Lu Xian-Ping , Jiang Ning-Yi
Published: September 2016

The aims of the present study were to analyze the outcomes of pregnancy, after 131I treatment, in patients of reproductive age with Graves’ hyperthyroidism and to investigate the effects, if any, of the 131I treatment on the mothers and newborns. From 2009 to 2014, 257 pregnant female patients with Graves’ hyperthyroidism in the outpatients at the Department of Nuclear Medicine and 166 healthy pregnant women from the Department of Obstetrics at Sun Yat-Sen Memorial Hospital were included in our study. They were divided into a 131I therapy group (n = 130) and an anti-thyroid drug (ATD) group (n = 127) according to their therapy before conception. The neonatal gender, rate of preterm birth, body weight ratio and occurrence of low birth weight [except for higher rates of abortion (odds ratio; OR = 2.023) and cesarean delivery (OR = 1.552) in patients with Graves’ hyperthyroidism] showed no statistically significant differences from those of the healthy group (P > 0.05). The level of intrauterine growth restriction did not differ between the Graves’ hyperthyroidism group and the healthy group (8 vs 2, 3.0% vs 1.2%). The outcomes of pregnancy among the 131I therapy group, ATD group and healthy group also showed no significant differences. Of the patients treated with 131I, no significant differences were observed in the outcomes of their pregnancies, whether they received propylthiouracil (PTU), levothyroxine or no additional drug treatment during pregnancy. Women with hyperthyroidism who were treated with 131I therapy could have normal delivery if they ceased 131I treatment for at least six months prior to conception and if their thyroid function was reasonably controlled and maintained using the medication: anti-thyroid drug and levothyroxine before and during pregnancy.
Building national laboratories to meet China's development challenges
Authors: Qiu Jane
Published: September 2016

China boasts one of the largest scientific forces in the world, but most research institutes focus on a specialized subject of research—which many say are insufficient to meet the country's complex development needs. As part of the reform of scientific institutions and the implementation of innovation-driven development strategies, the Chinese government plans to build several comprehensive national laboratories that it hopes will further boost its scientific research prowess and to support large-scale projects.

To rev up their construction and management, 12 of the world's top national-laboratory experts were invited to share their experiences and insights at the International Seminar on National Laboratory Management, which was held in Beijing on 2 February 2016. In a forum chaired by Tieniu Tan, Vice President of Chinese Academy of Sciences, a panel of four scientists discussed with a packed audience why multi-purpose national laboratories are important, how to manage them effectively, and what the main challenges are.

Hong Ding

Managing Director of Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences in Beijing, China

Doon Gibbs

Director of U.S. Department of Energy's Brookhaven National Laboratory in Upton, New York, USA

Antonio Masiero

Deputy President of the National Institute of Nuclear Physics (INFN), Italy

Joël Mesot

Director of Paul Scherrer Institute in Villigen, Switzerland

Tieniu Tan (Chair)

Vice President of Chinese Academy of Sciences, China
Diseases due to unhealthy environments: an updated estimate of the global burden of disease attributable to environmental determinants of health
Authors: Prüss-Ustün A. , Wolf J. , Corvalán C. , Neville T. , Bos R. , Neira M.
Published: September 2016

Background

The update of the global burden of disease attributable to the environment is presented. The study focuses on modifiable risks to show the potential health impact from environmental interventions.

Methods

Systematic literature reviews on 133 diseases and injuries were performed. Comparative risk assessments were complemented by more limited epidemiological estimates, expert opinion and information on disease transmission pathways. Population attributable fractions were used to calculate global deaths and global disease burden from environmental risks.

Results

Twenty-three percent (95% CI: 13–34%) of global deaths and 22% (95% CI: 13–32%) of global disability adjusted life years (DALYs) were attributable to environmental risks in 2012. Sixty-eight percent of deaths and 56% of DALYs could be estimated with comparative risk assessment methods. The global disease burden attributable to the environment is now dominated by noncommunicable diseases. Susceptible ages are children under five and adults between 50 and 75 years. Country level data are presented.

Conclusions

Nearly a quarter of global disease burden could be prevented by reducing environmental risks. This analysis confirms that eliminating hazards and reducing environmental risks will greatly benefit our health, will contribute to attaining the recently agreed Sustainable Development Goals and will systematically require intersectoral collaboration to be successful.
Physical Characteristics, Nutritional Quality, and Antioxidant Potential of Extrudates Produced with Polished Rice and Whole Red Bean Flours
Authors: Oliveira Ludmilla C. , Lima Diana C. N. , Bailoni Marcio A. , Risso Eder M. , Schmiele Marcio , Steel Caroline J. , Chang Yoon K.
Published: September 2016

In Brazil, rice (Oryza sativa L.) and beans (Phaseolus vulgaris L.) are the basis of the population's diet, and their consumption together is a good strategy to improve protein biological value. The aim of this study was to produce extruded products with whole red bean (WRBF) and polished rice (PRF) flours and to evaluate the effects of extrusion temperature (T) and feed moisture content (FM) on technological properties and total phenolic compounds content. The extrudates were elaborated in a twin‐screw extruder following a 22 central composite rotatable design with FM (15–23%) and T (120–160°C) as independent variables. WRBF and PRF were used at a 1:3 ratio. Amino acid content and profile were evaluated in the optimum extrudate (produced at FM = 19% and T = 140°C). The total phenolic content identified in extruded products was provided by the red bean seed coat, and its quantification suggested the release of bound phenolics with the extrusion process (not temperature dependent). The extrusion of PRF and WRBF, in combination, produced extruded products of high protein quality, being complete in essential amino acids for the diets of people at least 48 months old. The results indicate that legume flours such as WRBF incorporated into rice flour can cause a positive impact on technological, nutritional, and functional quality of extrudates.
Diverticular Disease of the Colon
Authors: Bassotti Gabrio , Villanacci Vincenzo , Bernardini Nunzia , Dore Maria P.
Published: September 2016

Colonic diverticular disease is a frequent finding in daily clinical practice. However, its pathophysiological mechanisms are largely unknown. This condition is likely the result of several concomitant factors occurring together to cause anatomic and functional abnormalities, leading as a result to the outpouching of the colonic mucosa. A pivotal role seems to be played by an abnormal colonic neuromuscular function, as shown repeatedly in these patients, and by an altered visceral perception. There is recent evidence that these abnormalities might be related to the derangement of the enteric innervation, to an abnormal distribution of mucosal neuropeptides, and to low-grade mucosal inflammation. The latter might be responsible for the development of visceral hypersensitivity, often causing abdominal pain in a subset of these patients.
Treatment of Diverticular Disease With Aminosalicylates
Authors: Barbara Giovanni , Cremon Cesare , Barbaro Maria R. , Bellacosa Lara , Stanghellini Vincenzo
Published: September 2016

Colonic diverticulosis is an increasingly common condition in Western industrialized countries. About 20% of patients develop symptoms, including abdominal pain, bloating, changes in bowel habits, and, eventually, diverticulitis or other complications. The management of symptomatic uncomplicated diverticular disease (SUDD) and the prevention of acute diverticulitis remains a challenge for the clinician. The rationale for the use of aminosalicylates, such as mesalazine, is based on the assumption of low-grade inflammation in SUDD and symptoms generation, whereas an overt inflammation may induce diverticulitis in patients with diverticular disease. Clinical scenarios in which the efficacy and safety of mesalazine have been studied include SUDD, prevention of diverticulitis, and of recurrent diverticulitis. Data from uncontrolled studies suggest a benefit of mesalazine on patients with SUDD, whereas data from randomized controlled trials showed some evidence of improvement of symptoms, although contrasting results are reported. The largest study so far published on the efficacy of mesalamine in the prevention of recurrence of diverticulitis showed that mesalamine was not superior to placebo. At this time, the role of mesalazine in the prevention of acute diverticulitis remains to be defined with many issues open and unresolved.
Assessment of Fecal Microbiota and Fecal Metabolome in Symptomatic Uncomplicated Diverticular Disease of the Colon
Authors: Tursi Antonio , Mastromarino Paola , Capobianco Daniela , Elisei Walter , Miccheli Alfredo , Capuani Giorgio , Tomassini Alberta , Campagna Giuseppe , Picchio Marcello , Giorgetti GianMarco , Fabiocchi Federica , Brandimarte Giovanni
Published: September 2016

Goal:

The aim of this study was to assess fecal microbiota and metabolome in a population with symptomatic uncomplicated diverticular disease (SUDD).

Background:

Whether intestinal microbiota and metabolic profiling may be altered in patients with SUDD is unknown.

Patients and Methods:

Stool samples from 44 consecutive women [15 patients with SUDD, 13 with asymptomatic diverticulosis (AD), and 16 healthy controls (HCs)] were analyzed. Real-time polymerase chain reaction was used to quantify targeted microorganisms. High-resolution proton nuclear magnetic resonance spectroscopy associated with multivariate analysis with partial least-square discriminant analysis (PLS-DA) was applied on the metabolite data set.

Results:

The overall bacterial quantity did not differ among the 3 groups (P=0.449), with no difference in Bacteroides/Prevotella, Clostridium coccoides, Bifidobacterium, Lactobacillus, and Escherichia coli subgroups. The amount of Akkermansia muciniphila species was significantly different between HC, AD, and SUDD subjects (P=0.017). PLS-DA analysis of nuclear magnetic resonance -based metabolomics associated with microbiological data showed significant discrimination between HCs and AD patients (R
2=0.733; Q
2=0.383; P<0.05, LV=2). PLS analysis showed lower N-acetyl compound and isovalerate levels in AD, associated with higher levels of A. municiphila, as compared with the HC group. PLS-DA applied on AD and SUDD samples showed a good discrimination between these 2 groups (R
2=0.69; Q
2=0.35; LV=2). SUDD patients were characterized by low levels of valerate, butyrate, and choline and by high levels of N-acetyl derivatives and U1.

Conclusions:

SUDD and AD do not show colonic bacterial overgrowth, but a significant difference in the levels of fecal A. muciniphila was observed. Moreover, increasing expression of some metabolites as expression of different AD and SUDD metabolic activity was found.
The Role of Colonoscopy in the Diverticular Disease
Authors: Grande Giuseppe , Zulli Claudio , Pigò Flavia , Riccioni Maria E. , Di Mario Francesco , Conigliaro Rita L.
Published: September 2016

Colonic diverticula are one of the most frequent conditions found during the endoscopic examination of the lower digestive tract, interestingly in >70% of people after 80 years old. Of them, only a few percentage develop complications such as acute diverticulitis or diverticular bleeding. Up to now, colonoscopy represents the most important diagnostic and therapeutic tool on the hands of the clinicians. On the basis of this the need for a standardized and reproducible approach is now emerging. This short review article is tasked to point out some open issues concerning the role of colonoscopy in diverticular disease.
Diverticular Disease and IBS
Authors: Spiller Robin
Published: September 2016

Although over half of patients over 65 years old will have diverticulosis, only a minority experience symptoms. These are often similar to those of irritable bowel syndrome with pain and disordered bowel habit, but differ in having an onset in the sixth to seventh decade. The underlying mechanisms include visceral hypersensitivity which maybe postinflammatory, but may also be due to altered central pain processing. Somatization is a useful clue to a predominantly central pathology, while its absence points to local causes including altered enteric nerves and mucosal immune activation. Treatments should be tailored to the individual patient who shows either predominantly peripheral or central abnormalities.
Intestinal Ultrasonography in the Diagnosis and Management of Colonic Diverticular Disease
Authors: Maconi Giovanni , Carmagnola Stefania , Guzowski Tom
Published: September 2016

Diverticula of the colon and their symptomatic manifestations, including acute diverticulitis (AD), are frequent complaints and the cause of an increasing burden of ambulatory visits, diagnostic procedures, and hospital admissions. Endoscopic and radiologic diagnostic procedures have a well-known role in the diagnosis and management of the disease, but recently intestinal ultrasonography has been proposed as a complementary tool in the diagnosis and follow-up of diverticular disease. This review shows the main sonographic features of diverticula and discusses the potential role of ultrasound in suggesting the presence of symptomatic uncomplicated diverticular disease of the colon. Moreover, the sonographic features of AD, diagnostic accuracy, advantages, and limitations of the technique will be discussed. We place special emphasis on the present role of intestinal ultrasonography in patients with suspected AD. Owing to its high sensitivity and high positive predictive value in assessing AD, intestinal ultrasound is currently suggested by some European national consensus guidelines as the first-line examination in this setting. In fact, to minimize false-negative findings and avoid unnecessary radiation exposure in patients with suspected AD, intestinal ultrasound might be used as the first-line examination in a sequential diagnostic strategy, followed by computed tomography only in the case of negative or inconclusive findings.
A Primary-Care Interventional Model on the Diverticular Disease
Authors: Campanini Angelo , De Conto Umberto , Cavasin Francesco , Bastiani Fernanda , Camarotto Antonio , Gardini Luigi , Geremia Alessandra , Marastoni Cristina , Missorini Carlo , Quarantelli Elena , Sassi Umberto , Scarabello Francesco , Dal Bo Nadia , Riccò Matteo , Grillo Simone , Landi Stefano , Di Mario Francesco
Published: September 2016

Introduction

In routine colonoscopy, diverticulosis is the most commonly found feature, but only a minority of these cases show symptoms of diverticular disease.

From June 2014 to December 2014, we enrolled prospectively 178 patients affected by symptomatic uncomplicated diverticular disease (Male/Female=0.47, mean age 71.7±11.5 y, range 41 to 95 y) from 15 General Pratictioners patient files. All patients were symptomatic; in all cases, diagnosis was been confirmed by a colonoscopy performed at least 1 year before. Patients with acute diverticulitis were excluded.

On the basis of the predominant symptoms (abdominal complaints or constipation), patients were addressed to 4 different therapeutic approaches using mesalamine, rifaximine, probiotics (in a consortium of different species of Lactobacillus and Bifidobacterium), and fibers (Plantago Ovata Husk). All treatments lasted 3 months.

Results:

Sixty-three patients were enrolled in group A (rifaximine), 43 in group A1 (rifaximine+fibers+probiotics), 23 in group B (mesalamine), and 31 in group B1 (mesalamine+fibers).

Analysis of variance suggested a statistically significant difference (P<0.003) among groups at the end of the observation period, with Groups A1 and B1 showing a higher number of bowel movement per week. Global linear measurement confirmed the role of treatment as a significant factor (F=2.858; P=0.039) associated with body mass index (F=6.972; P<0.009).

Conclusions:

In accordance with the baseline clinical presentation, the supplementation of fiber and/or probiotics is associated with a statistically significant improvement in the clinical pattern of symptoms in patients with diverticular disease in a primary-care/family physician setting.
Comparison of Cytokine and Efflux Transporter Expression in Pediatric Versus Adult‐onset Ulcerative Colitis
Authors: Savić Mlakar Ana , Hojsak Iva , Jergović Mladen , Vojvoda Parčina Valerija , Babić Žarko , Troskot Branko , Mihaljević Željko , Bendelja Krešo
Published: September 2016

Objectives:

Ulcerative colitis (UC), a chronic inflammation of the colon, is often more severe in children than adults. Identification of altered expression of efflux transporters, cytokines, and suppressor of cytokine signaling (SOCS) molecules in pediatric versus adult patients could provide insight into the differential molecular patterns related to the age and disease pathology.

Methods:

Mucosal samples from terminal ileum and colon in pediatric (9 UC‐New, 4 UC‐Remission) and adult (9 UC‐New, 8 UC‐Remission) patients were compared with healthy subjects (15 children and 10 adults) for mRNA expressions of several efflux transporters, cytokines, and SOCS molecules.

Results:

The inflamed colon interleukin (IL)‐6, IL‐17A, and interferon‐γ levels were elevated in UC‐New subgroups but close to control values in UC‐Remission. IL‐1β expression was increased only in UC‐New children. Interestingly, uninflamed ileum also showed increased IL‐6 and IL‐1β levels in UC‐New subgroups. SOCS1/SOCS3 expression pattern followed a trend observed for inflammatory cytokines only in children. Both children and adults had decreased multidrug resistance protein 1 expression in colon, which inversely correlated with disease score, IL‐6 and interferon‐γ levels in UC‐New children. IL‐2 expression was upregulated in UC‐Remission, compared with controls.

Conclusions:

Efflux transporter expression varies between UC children and adults except for decreased multidrug resistance protein 1. UC is characterized by a dysregulated TH1 and TH17 cytokine response irrespective of age at disease onset, with higher cytokine levels detected in children. Increased IL‐2 levels in remission imply a protective role for regulatory T cells (Tregs).
Sex in a test tube: testing the benefits of
in vitro
recombination
Authors: Pesce Diego , Lehman Niles , de Visser J. Arjan G. M.
Published: September 2016

The origin and evolution of sex, and the associated role of recombination, present a major problem in biology. Sex typically involves recombination of closely related DNA or RNA sequences, which is fundamentally a random process that creates but also breaks up beneficial allele combinations. Directed evolution experiments, which combine
in vitro
mutation and recombination protocols with
in vitro
or
in vivo
selection, have proved to be an effective approach for improving functionality of nucleic acids and enzymes. As this approach allows extreme control over evolutionary conditions and parameters, it also facilitates the detection of small or position-specific recombination benefits and benefits associated with recombination between highly divergent genotypes. Yet,
in vitro
approaches have been largely exploratory and motivated by obtaining improved end products rather than testing hypotheses of recombination benefits. Here, we review the various experimental systems and approaches used by
in vitro
studies of recombination, discuss what they say about the evolutionary role of recombination, and sketch their potential for addressing extant questions about the evolutionary role of sex and recombination, in particular on complex fitness landscapes. We also review recent insights into the role of ‘extracellular recombination’ during the origin of life.

This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’.
What can we infer about the origin of sex in early eukaryotes?
Authors: Speijer Dave
Published: September 2016

Current analysis shows that the last eukaryotic common ancestor (LECA) was capable of full meiotic sex. The original eukaryotic life cycle can probably be described as clonal, interrupted by episodic sex triggered by external or internal stressors. The cycle could have started in a highly flexible form, with the interruption of either diploid or haploid clonal growth determined by stress signals only. Eukaryotic sex most likely evolved in response to a high mutation rate, arising from the uptake of the endosymbiont, as this (proto) mitochondrion generated internal reactive oxygen species. This is consistent with the likely development of full meiotic sex from a diverse set of existing archaeal (the host of the endosymbiont) repair and signalling mechanisms. Meiotic sex could thus have been one of the fruits of symbiogenesis at the basis of eukaryotic origins: a product of the merger by which eukaryotic cells arose. Symbiogenesis also explains the large-scale migration of organellar DNA to the nucleus. I also discuss aspects of uniparental mitochondrial inheritance and mitonuclear interactions in the light of the previous analysis.

This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’.
Unholy marriages and eternal triangles: how competition in the mushroom life cycle can lead to genomic conflict
Authors: Vreeburg Sabine , Nygren Kristiina , Aanen Duur K.
Published: September 2016

In the vast majority of sexual life cycles, fusion between single-celled gametes is directly followed by nuclear fusion, leading to a diploid zygote and a lifelong commitment between two haploid genomes. Mushroom-forming basidiomycetes differ in two key respects. First, the multicellular haploid mating partners are fertilized in their entirety, each cell being a gamete that simultaneously can behave as a female, i.e. contributing the cytoplasm to a zygote by accepting nuclei, and a male gamete, i.e. only donating nuclei to the zygote. Second, after gamete union, the two haploid genomes remain separate so that the main vegetative stage, the dikaryon, has two haploid nuclei per cell. Only when the dikaryon produces mushrooms, do the nuclei fuse to enter a short diploid stage, immediately followed by meiosis and haploid spore formation. So in basidiomycetes, gamete fusion and genome mixing (sex) are separated in time. The ‘living apart together’ of nuclei in the dikaryon maintains some autonomy for nuclei to engage in a relationship with a different nucleus. We show that competition among the two nuclei of the dikaryon for such ‘extramarital affairs’ may lead to genomic conflict by favouring genes beneficial at the level of the nucleus, but deleterious at that of the dikaryon.

This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’.
Androgenesis: where males hijack eggs to clone themselves
Authors: Schwander Tanja , Oldroyd Benjamin P.
Published: September 2016

Androgenesis is a form of quasi-sexual reproduction in which a male is the sole source of the nuclear genetic material in the embryo. Two types of androgenesis occur in nature. Under the first type, females produce eggs without a nucleus and the embryo develops from the male gamete following fertilization. Evolution of this type of androgenesis is poorly understood as the parent responsible for androgenesis (the mother) gains no benefit from it. Ultimate factors driving the evolution of the second type of androgenesis are better understood. In this case, a zygote is formed between a male and a female gamete, but the female genome is eliminated. When rare, androgenesis with genome elimination is favoured because an androgenesis-determining allele has twice the reproductive success of an allele that determines sexual reproduction. Paradoxically, except in hermaphrodites, a successful androgenetic strain can drive such a male-biased sex ratio that the population goes extinct. This likely explains why androgenesis with genome elimination appears to be rarer than androgenesis via non-nucleate eggs, although both forms are either very rare or remain largely undetected in nature. Nonetheless, some highly invasive species including ants and freshwater clams are androgenetic, for reasons that are largely unexplained.

This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’.
What does the geography of parthenogenesis teach us about sex?
Authors: Tilquin Anaïs , Kokko Hanna
Published: September 2016

Theory predicts that sexual reproduction is difficult to maintain if asexuality is an option, yet sex is very common. To understand why, it is important to pay attention to repeatably occurring conditions that favour transitions to, or persistence of, asexuality. Geographic parthenogenesis is a term that has been applied to describe a large variety of patterns where sexual and related asexual forms differ in their geographic distribution. Often asexuality is stated to occur in a habitat that is, in some sense, marginal, but the interpretation differs across studies: parthenogens might not only predominate near the margin of the sexuals' distribution, but might also extend far beyond the sexual range; they may be disproportionately found in newly colonizable areas (e.g. areas previously glaciated), or in habitats where abiotic selection pressures are relatively stronger than biotic ones (e.g. cold, dry). Here, we review the various patterns proposed in the literature, the hypotheses put forward to explain them, and the assumptions they rely on. Surprisingly, few mathematical models consider geographic parthenogenesis as their focal question, but all models for the evolution of sex could be evaluated in this framework if the (often ecological) causal factors vary predictably with geography. We also recommend broadening the taxa studied beyond the traditional favourites.

This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’.
UCHIME2: improved chimera prediction for amplicon sequencing
Authors: Edgar Robert C.
Published: September 2016

Amplicon sequencing generates chimeric reads which can cause spurious inferences of biological variation. I describe UCHIME2, an update of the popular UCHIME chimera detection algorithm with new modes optimized for high-resolution biological sequence reconstruction (“denoising”) and other applications. I show that chimera frequency correlates inversely with divergence, that error-free chimera prediction from sequence is impossible in principle, and that UCHIME2 achieves higher detection accuracy than previous methods.
Rabix: an open-source workflow executor supporting recomputability and interoperability of workflow descriptions
Authors: Kaushik Gaurav , Ivkovic Sinisa , Simonovic Janko , Tijanic Nebojsa , Davis-Dusenbery Brandi , Kural Deniz
Published: September 2016

As biomedical data has become increasingly easy to generate in large quantities, the methods used to analyze it have proliferated rapidly. Reproducible and reusable methods are required to learn from large volumes of data reliably. To address this issue, numerous groups have developed workflow specifications or execution engines, which provide a framework with which to perform a sequence of analyses. One such specification is the Common Workflow Language, an emerging standard which provides a robust and flexible framework for describing data analysis tools and workflows. In addition, reproducibility can be furthered by executors or workflow engines which interpret the specification and enable additional features, such as error logging, file organization, optim1izations tocomputation and job scheduling, and allow for easy computing on large volumes of data. To this end, we have developed the Rabix Executora, an open-source workflow engine for the purposes of improving reproducibility through reusability and interoperability of workflow descriptions.
Fast algorithm for determining orientations using angular correlation functions and Bayesian statistics
Authors: Huang Lanqing , Liu Haiguang
Published: September 2016

Cryogenic electron microscopy (cryo-EM) method achieved revolutionary improvement in the past a few years, yet the orientation recovery for each particle remains computational challenging. Orientation determination can be solved using Bayesian approach, through which a model can be constructed to best match a whole set of experimental projections at their ‘correct orientations’. Without considering the centering of each particle projection, there are three degrees of freedoms (three Euler angles) that need to be fixed, usually resulting a computational complexityO(n3) wherenis the number of discretization for each rotation angle. Here, we propose a method based on Maximum Likelihood approach with angular auto-correlation function of each projection, which is utilized to decouple the determination of three Euler angles to stepwise determination of two Euler angles and the subsequent third angle, the in-plane rotation. This approach reduces computational complexity fromO(n3) toO(n2). Using simulation data, the accuracy and speed of the method is compared with the original maximum likelihood approach. We also investigated the impact of noise to the performance of this proposed method.
A new alkaline earth metal tetrafluoroterephthalate: [Ba(tfBDC)(DMF)(EtOH)]
Authors: Smets Daniel , Sobieray Miriam , Ruschewitz Uwe
Published: September 2016

[Ba(C8F4O4)(C3H7NO)(C2H5OH)] or [Ba(tfBDC)(DMF)(EtOH)], where tfBDC2−= tetrafluoroterephthalate, DMF = dimethylformamide, EtOH = ethanol, systematic name poly[(dimethylformamide-1κO)(ethanol-1κO)(μ5-2,3,5,6-tetrafluorobenzenedicarboxylato-1:2κ2O1;1:3κ2O1′;4κO4;5κO4′)barium(II)], has been synthesized by a diffusion controlled synthesis from an EtOH/DMF solution. In the crystal structure two crystallographically independent Ba2+cations are linked by two crystallographically distinct tfBDC2−anions to form a three-dimensional network structure. The coordination spheres of the first (CN = 8) and second (CN = 8) independent Ba cations are completed by the O atoms of DMF and EtOH molecules, with both EtOH molecules being disordered over two sets of sites (occupancy ratio 0.7:0.3 and 0.6:0.4, respectively).
Bis(dimethylamido-κN)bis[2-(pyrrol-2-ylmethyleneamino)-2′-methoxy-6,6′-dimethyl-1,1′-biphenyl-κ2N,N′]vanadium(IV) toluene monosolvate
Authors: Wang Qiuwen , Xiong Yihan , Deng Xuebin
Published: September 2016

Reaction of the Schiff base ligand (R)-2-(pyrrol-2-ylmethyleneamino)-2′-methoxy-6,6′-dimethyl-1,1′-biphenyl with tetrakis(dimethylamido)vanadium in toluene gives the mononuclear VIVtitle complex, [V(C2H6N)2(C20H19N2O)2]·C7H8, which was isolated as red crystals. The VIVcation is coordinated by two monoanionic bidentate Schiff base ligands and two N atoms of two dimethylamide anions in a VN6distorted octahedral coordination geometry, in which two N atoms from the dimethylamide anions are placed in acis-configuration.
Cooperation and information sharing in institutional food chains
Authors: Evensen Kjersti Berge , Hansen Håvard
Published: September 2016

Purpose

The purpose of this paper is to investigate integrative practices within institutional food chains with special emphasis on cooperation and information sharing.

Design/methodology/approach

A qualitative approach was applied, based on 17 in-depth interviews with staff from four different institutions. The data collection and analysis were guided by constructivist grounded theory.

Findings

In summary, the authors find that: low differentiation lead to a high level of service variability at the satellite kitchens, high level of optimizing behavior lead to a high level of service variability, there is a positive relationship between food task involvement and access to the information being shared, there is a positive relationship between food task involvement and participation in cooperation activities and when the physical distance between stages in the chain increases, the information sharing will deteriorate.

Research limitations/implications

To empirically generalize the findings, this first qualitative study should be followed up by a quantitative study.

Practical implications

Based on the findings, the authors suggest that the chains would benefit from improving the interfaces between front line employees, and share information more extensively. The location of the central kitchen seems to influence information sharing across stages in the food chains.

Originality/value

To the authors’ knowledge this is the first study that examines cooperation and information sharing practices within institutional food chains.
Segmentation of Chinese parents based on food risk perception dimensions for risk communication in rural area of Sichuan province
Authors: Li Jiajie , Li Nan , Luo Lang , Ren Yanan
Published: September 2016

Purpose

The purpose of this paper is to investigate risk dimensions affecting food risk perceptions and to develop effective risk communication strategies based on their risk perceptions dimensions. The reason for writing this paper is that applying single risk communication strategy for public often fails because food risks are systemic risks and public perceptions toward them consist of multiple dimensions. Launching an effective risk communication need to investigate the perception dimensions of the target audience.

Design/methodology/approach

A total of 2,673 parents of 3-14-year-old children from the rural area of Sichuan province in China were chosen as target audience. Based on the survey conducted about parents’ food risk perceptions, this study used factor-cluster analysis method to segment parents to sub-clusters with significantly different risk perception dimensions. Parents’ representative demographic characteristics within each cluster were further identified through cross-tabs analysis with χ2 tests.

Findings

All the parents could be segmented into four sub-clusters, namely, sensitive parents, dependent parents, familiarity-oriented parents and institutional distrust parents, according to their risk perception difference on five dimensions. A series of risk communication strategies were specifically designed for each cluster based on their risk perception features as well as demographic characteristics.

Originality/value

The insight derived from this study described a deeper image of public risk perceptions and provided suggestions for risk communication launchers to pinpoint the risk perception as well as perception dimensions of the target audience and accordingly develop effective risk communication strategies.
Segmentation of consumer preference for food safety label on vegetables
Authors: Adasme-Berríos Cristian , Sanchez Mercedes , Mora Marcos , Schnettler Berta , Lobos German , Díaz José
Published: September 2016

Purpose

The purpose of this paper is to explore the differences in consumers’ preferences to food safety label (FSL) on vegetables in central and south central Chile in terms of sociodemographic characteristics, consumers’ food safety knowledge and frequency of vegetables consumption.

Design/methodology/approach

A survey was applied to 1,201 consumers in charge of buying vegetables for their households. The questionnaire measured consumer preference for FSL using tomatoes as a case study.

Findings

The most important attributes for consumers were price (57.3 percent), FSL (19.7 percent), point of sale (11.86 percent) and production system (11.07 percent). Cluster analysis was used to differentiate three types of consumers. The majority (50.5 percent) are consumers oriented to price of tomatoes more than other attributes. A second group (30.1 percent) considers it important to purchase tomatoes at the lowest price with the existence of a FSL. A minority (19.4 percent) was oriented to purchasing tomatoes with a FSL. The groups differ according to sociodemographic characteristics, food safety knowledge and frequency of vegetables consumption.

Research limitations/implications

The study was conducted in country in South America. The results revealed that the majority of consumers choose price over FSL. Nevertheless, a potential market niche was identified that was motivated by FSL as a potential risk-reduction strategy when making choices about fresh vegetables purchase.

Practical implications

FSL is a marketing tool to help the consumers about food decisions.

Social implications

To avoid problems associated to unsafe vegetables, FSL is used as a potential risk-reduction strategy when making choices about fresh vegetables purchase.

Originality/value

The research provides information about a market niche of consumers interested in the existence of an explicit FSL, due to their awareness of the risks associated with the consumption of vegetables. This topic has received little research in Latin American developing countries.
Market potential of lignans and omega-3 functional cookies
Authors: Cukelj Nikolina , Putnik Predrag , Novotni Dubravka , Ajredini Saša , Voucko Bojana , Curic Duška
Published: September 2016

Purpose

Cookies were not generally viewed as functional contributors to well-being as they are primarily perceived as confectionery products. The purpose of this paper is to evaluate the potential of flaxseed-enriched cookies as carriers of lignans and omega-3 fatty acids – functional compounds that are lacking in the western diet.

Design/methodology/approach

An online questionnaire collected data from Croatian consumers (n=1,035). The majority of the samples were women (73 per cent) in the age range 15-65 years (97 per cent). Most participants were employed, had a higher education degree, and lived in urban areas. Questions examined the consumption of cookies and flaxseed, interest for functional cookies, nutritional knowledge, and awareness.

Findings

Majority of subjects consumed cookies (93 per cent), while 61 per cent did not eat flaxseed or ate it less than once a month. The consumers showed elevated interest for the functional cookies with flaxseed, among which elderly women with higher nutrition awareness, and nutrition knowledge were the most interested. Functional cookies with flaxseed could be used for delivery of lignans and omega-3 fatty acids in everyday diet, but in order to reach wider range of consumers producers might benefit from employing nutritional educational marketing campaigns.

Originality/value

Data from the study decreased scarcity of information on consumer behaviour related to flaxseed consumption and on potential use of cookies as a functional food. Reported findings will be useful to dieticians, food industry, and food researchers in countries with a high prevalence of cookie consumption.
Entrepreneurial intention in the time of crisis: a field study
Authors: Arrighetti Alessandro , Caricati Luca , Landini Fabio , Monacelli Nadia
Published: September 2016

Purpose

The purpose of this paper is to investigate the impact of a prolonged economic recession on the entrepreneurial intentions of young people (university students) distinguishing between propensity to start a new business (i.e. degree of interest in entrepreneurship) and perceived likelihood of becoming an entrepreneur (i.e. probability to start a business in the future). Furthermore this study verifies if the recession strengthens the orientation to exploit new market opportunities, or simply supports self-employment objectives.

Design/methodology/approach

Entrepreneurial intention was measured in terms of propensity to start a new business and perceived likelihood of becoming an entrepreneur. Psychosocial and economic variables were measured as well. Information was gathered through questionnaires distributed in both electronic and paper-and-pencil form to a sample of 3,684 Italian University students enrolled in 12 different faculties.

Findings

First, this study found that while the perception of the economic crisis as an obstacle to new business creation does not impact on the propensity toward entrepreneurship, it has a negative and highly significant impact on the likelihood to start a business. Second, when a distinction is made between opportunity- and necessity-based types, results show that while for the latter the crisis impacts only on the perceived likelihood to become an entrepreneur, for the former it affects both dimensions of entrepreneurship, i.e., both propensity and perceived likelihood. Moreover, neither family support nor economic institutions are perceived as relevant in sustaining entrepreneurial intentions. On the contrary, the university is considered as a key support entity.

Research limitations/implications

Reliance on cross-sectional questionnaires instead of an experimental design imposes caution about the causal relationships between predictors and entrepreneurial intent.

Originality/value

The present paper is one of the few studies concerning the influence of rapid worsening of external economic context (severe recession) on the entrepreneurial intent.
Study of the mechanical and the thermal insulation properties of polyurethane coating containing chicken eggshell and rice husk ash as fillers
Authors: Ang Bee Chin , Ahmad Norasikin , Ong Zhi Chao , Cheok Shun Chi , Chan Hui Fen
Published: September 2016

Purpose

The main aim of this study was to examine the effects of chicken eggshell (CES) and rice husk ash (RHA) as fillers on the mechanical and the thermal insulation properties of polyurethane coatings.

Design/methodology/approach

CES and RHA were ground via ball milling set at different parameters, and the smallest particles size obtained were selected and used as fillers. Fillers of different weight proportions were mixed with other components such as binder, solvent and pigment to form various coating formulations and test samples were made via dip coating. A series of characterisations were conducted to analyse the thermal and mechanical properties of the coating.

Findings

The smallest particle size of CES and RHA was obtained after both of them had undergone grinding process at 400 rpm within 180 min. Morphological studies revealed that CES and RHA have irregular shape and high porosity. In crystallographic analysis, CES mainly composed of pure calcite crystal structure and RHA contained amorphous silica. Both of fillers were found thermally stable up to 520 and 710°C for RHA and CES, respectively. In RHA individual system, as the RHA proportion increases, the thermal conductivity of the coating declined. In contrast, in the CES coating system, the thermal conductivity demonstrated an opposite trend. Thermal gravimetric analysis results displayed that by adding hybrid fillers, the residue weight and the thermal stability of the coatings were increased. In addition, the adhesion strength of the coating was increased as the filler weight content increased.

Research limitations/implications

Fillers with nano-range size were expected to be produced in this research for better performance of the coating. However, the obtained fillers were limited to micron size through dry grinding method. Another drawback in this research was the coating technique which is dip coating. The coated substrates do not have uniform coating thickness and this subsequently influenced the performance.

Originality/value

A novel attempt has been made to study the formulation coating system by mixing CES and RHA as fillers which is also known as a hybrid system.