bluuebunny/crossref_metadata_2025 huggingface dataset:
Entre textos e práticas: ensino de história, instituição escolar e formação docente
Authors: Ribeiro Renilson Rosa
Published: February 2016

O presente artigo tem a finalidade de debater a relação entre história ensinada, instituição escolar e formação docente a partir da historiografia do Ensino de História no Brasil produzida nas últimas quatro décadas, evidenciando os dilemas, problemas e perspectivas da prática docente na construção da identidade do profissional da História. Inicialmente o texto apresenta um estado da arte acerca da definição do campo de pesquisa chamado “Ensino de História”. Em seguida, analisa como alunos e professores são interpretados e representados no discurso curricular contemporâneo, tendo por referência os Parâmetros Curriculares Nacionais. A formação do professor de História na perspectiva da formulação dos currículos das licenciaturas/bacharelados é a questão desenvolvida posteriormente com a finalidade de evidenciar as armadilhas do discurso que separa a pesquisa do ensino. No final, retomamos o debate sobre o lugar e a relevância da sala de aula, no contexto da educação básica, para a formação e a prática docente.
Medical management of benign prostatic hyperplasia: Results from a population-based study
Authors: Bishr Mohamed , Boehm Katharina , Trudeau Vincent , Tian Zhe , Dell’Oglio Paolo , Schiffmann Jonas , Jeldres Claudio , Sun Maxine , Shariat Sharokh F. , Graefen Markus , Saad Fred , Karakiewicz Pierre I.
Published: February 2016

Introduction: In men with bothersome lower urinary tract symptoms (LUTS), medical treatment usually represents the first line. We examined the patterns of medical management of benign prostatic hyperplasia (BPH) in the Montreal metropolitan area, within the context of a case control study focusing on incident prostate cancer.

Methods: Cases were 1933 men with incident prostate cancer. Population controls included 1994 age-matched men. In-person interviews collected sociodemographic characteristics and medical history, including BPH diagnosis, its duration, and type of medical treatment received. Baseline characteristics were compared by the chi-square likelihood test for categorical variables and by the students t-test for continuously coded variables.

Results: Overall, 1120 participants had history of BPH, of those 53.7% received medical treatment for BPH. Individuals with medically treated BPH, compared to individuals with medically untreated BPH, were older at index date [mean: 66.9 vs. 64.9 years, p˂0.001] and at diagnosis of BPH [mean: 62.3 vs. 60.3 years, p˂0.001]. They also had a longer duration of BPH-history [mean: 4.7 vs. 4.0 years, p=0.02]. Regarding medical treatment, monotherapy was more often used than combination therapy [87.6% vs. 12.4%, p˂0.001]. Alpha-blockers (69.9%) were most commonly used as monotherapy, followed by 5alpha-reductase inhibitors (5ARIs) (26.6%). Alpha-blockers plus 5ARIs were the most common combination therapy (97.3%).

Conclusions: Despite evidence from randomized, controlled trials for better efficacy with use of combination therapy, monotherapy consisting of alpha-blockers or 5ARI, in that order, is most frequently used. Additionally, 5ARI use was more common than previously reported (27% vs. 15%).
Qualitative Twitter analysis of participants, tweet strategies, and tweet content at a major urologic conference
Authors: Borgmann Hendrik , Woelm Jan-Henning , Merseburger Axel , Nestler Tim , Salem Johannes , Brandt Maximilian P. , Haferkamp Axel , Loeb Stacy
Published: February 2016

Introduction: The microblogging social media platform Twitter is increasingly being adopted in the urologic field. We aimed to analyze participants, tweet strategies, and tweet content of the Twitter discussion at a urologic conference.

Methods: A comprehensive analysis of the Twitter activity at the European Association of Urology Congress 2013 (#eau2013) was performed, including characteristics of user profiles, engagement and popularity measurements, characteristics and timing of tweets, and content analysis.

Results: Of 218 Twitter contributors, doctors (45%) were the most frequent, ahead of associations (15%), companies (10%), and journals (3%). However, journals had the highest tweet/participant rate (22 tweets/participant), profile activity (median: 1177 total tweets, 1805 followers, 979 following), and profile popularity (follower/following ratio: 2.1; retweet rank percentile: 96%). Links in a profile were associated with higher engagement (p<0.0001) and popularity (p<0.0001). Of 1572 tweets, 57% were original tweets, 71% contained mentions, 20% contained links, and 25% included pictures. The majority of tweets (88%) were during conference hours, with an average of 24.7 tweets/hour and a peak activity of 71 tweets/hour. Overall, 59% tweets were informative, led by the topics uro-oncology (21%), urologic research (21%), and urotechnology (12%). Limitations include the analysis of a single conference, assessment of global profile and not domain-specific activity, and the rapid evolution in Twitter-using habits.

Conclusion: Results of this qualitative analysis are promising for an enrichment of the scientific discussions at urologic conferences through the use of Twitter.
The effect of wide resection during radical prostatectomy on surgical margins
Authors: Lavallée Luke T. , Stokl Andrew , Cnossen Sonya , Mallick Ranjeeta , Morash Chris , Cagiannos Ilias , Breau Rodney H.
Published: February 2016

Introduction: The impact of nerve-sparing on positive surgical margins during radical prostatectomy (RP) remains unclear. The objective of this study was to determine the incidence of positive surgical margins with a wide resection compared to a nerve-sparing technique.

Methods: A consecutive, single-surgeon patient cohort treated between August 2010 and November 2014 was reviewed. A standardized surgical approach of lobe-specific nerve-spare or wide resection was performed. Lobe-specific margin status and tumour stage were obtained from pathology reports. Univariable and multivariable associations between nerve management technique and lobe-specific positive surgical margin were determined.

Results: Of 388 prostate lobes, wide resection was performed in 105 (27%) and nerve-sparing in 283 (73%). In 273 lobes without extra-prostatic extension (EPE), 0 of 52 (0%) had a positive margin when wide resection was performed compared to 20 of 221 (9%) if nerve-sparing was performed (p=0.02). In 115 lobes with EPE, 11 of 53 (21%) had a positive margin if wide resection was performed compared to 28 of 62 (45%) if nerve-sparing was performed (p=0.006). In multivariable analysis, the risk of a positive margin was decreased among patients who received wide resection as compared to nerve-spare (RR 0.43, 95% CI 0.26‒0.71; p=0.001).

Conclusions: Surgical techniques to reduce positive surgical margins have become increasingly important as more patients with high-risk cancer are selecting surgery. The risk of a positive margin was greatly reduced using a standardized wide resection technique compared to nerve-sparing.
A primer on tumour immunology and prostate cancer immunotherapy
Authors: Ren Runhan , Koti Madhuri , Hamilton Thomas , Graham Charles H. , Nayak Jasmir G. , Singh Jas , Drachenberg Darrel E. , Siemens D. Robert
Published: February 2016

No abstract
What If There Is Nobody Around to Speak English? Then Keep Your Voice Diary
Authors: Yaman Ismail
Published: February 2016

This study aims to explore English Language Teaching (ELT) prep-class students’ perceptions of keeping personal voice diaries via a voice recorder as a way to extend speaking practice beyond the classroom walls. Following a ten-week treatment under which 12 voluntary students attending ELT prep-class at Ondokuz Mayıs University kept voice diaries in English outside the school on a regular daily basis, data were collected through semi-structured interviews. The qualitative analyses of the students’ answers indicate that an overwhelming majority of them regard speaking as a challenging skill due to factors like lack of fluency and excessive anxiety. As for the accessible chances to practice oral English, most of the participants report that there is an apparent inadequacy of opportunities beyond school. When asked about the contribution of individual voice diaries to the alleviation of the lack-of-practice-opportunities problem, almost all of the participants except one evaluate keeping voice diaries as an effective means of speaking improvement. It is praised mostly for its boosting effect on self-expression skills, fluency, and pronunciation; and for its lowering effect on anxiety and stress. In line with the findings of this study, it can be concluded that there is no equivalent substitute for the improvement of oral skills through dialogue and interaction between human beings in flesh and blood; however, keeping voice diaries on an individual basis can somehow help EFL learners overcome the limited conditions they face during their struggle to practice and improve oral English.
Correction of Footdrop Due to Multiple Sclerosis Using the STIMuSTEP Implanted Dropped Foot Stimulator
Authors: Taylor Paul N. , Wilkinson Hart Ingrid A. , Khan Mansoor S. , Slade-Sharman Diana E.M.
Published: February 2016

Background: Footdrop is a significant problem in multiple sclerosis, reducing the safety and efficiency of walking. Functional electrical stimulation (FES) can produce dorsiflexion, correcting footdrop. The purpose of this retrospective analysis of clinical study data was to compare the effect of external and implanted FES devices for the correction of footdrop.

Methods: External FES was used for a minimum of 6 months before implantation. Walking performance was assessed using 10-m walking speed, 3-minute walking distance, the Physiological Cost Index, and health- and device-related quality of life and device-use questionnaires. Assessments were made before implantation and a mean (SD) of 128 (24) days after surgery, with additional walking speed measurements at 3 years.

Results: Twenty-three people with multiple sclerosis received the STIMuSTEP implant. Both devices enabled statistically significant increases in walking speed and walking distance, with a strong trend toward a reduced Physiological Cost Index, indicating that walking required less effort (P = .07). Both devices improved device-related quality of life. Walking speed gain with FES was maintained at 3 years. Three implants failed after falls, and there was one case of neuropraxia. The implant was used more days per week and was quicker to put on each day than the external FES device.

Conclusions: The STIMuSTEP implanted dropped foot stimulator is an effective long-term intervention for the correction of footdrop.
Crystallization behavior of amorphous indium–gallium–zinc-oxide films and its effects on thin-film transistor performance
Authors: Suko Ayaka , Jia JunJun , Nakamura Shin-ichi , Kawashima Emi , Utsuno Futoshi , Yano Koki , Shigesato Yuzo
Published: February 2016

Amorphous indium–gallium–zinc oxide (a-IGZO) films were deposited by DC magnetron sputtering and post-annealed in air at 300–1000 °C for 1 h to investigate the crystallization behavior in detail. X-ray diffraction, electron beam diffraction, and high-resolution electron microscopy revealed that the IGZO films showed an amorphous structure after post-annealing at 300 °C. At 600 °C, the films started to crystallize from the surface with c-axis preferred orientation. At 700–1000 °C, the films totally crystallized into polycrystalline structures, wherein the grains showed c-axis preferred orientation close to the surface and random orientation inside the films. The current–gate voltage (I
d–V
g) characteristics of the IGZO thin-film transistor (TFT) showed that the threshold voltage (V
th) and subthreshold swing decreased markedly after the post-annealing at 300 °C. The TFT using the totally crystallized films also showed the decrease in V
th, whereas the field-effect mobility decreased considerably.
Ischemic postconditioning influences electron transport chain protein turnover in Langendorff-perfused rat hearts
Authors: Cao Song , Liu Yun , Wang Haiying , Mao Xiaowen , Chen Jincong , Liu Jiming , Xia Zhengyuan , Zhang Lin , Liu Xingkui , Yu Tian
Published: February 2016

Ischemia postconditioning (IPo) is a promising strategy in reducing myocardial ischemia reperfusion (I/R) injury (MIRI), but its specific molecular mechanism is incompletely understood. Langendorff-perfused isolated rat hearts were subjected to global I/R and received IPo in the absence or presence of the mitochondrial ATP-sensitive potassium channel (mitoKATP) blocker 5-hydroxydecanoate (5-HD). Myocardial mitochondria were extracted and mitochondrial comparative proteomics was analyzed. IPo significantly reduces post-ischemic myocardial infarction and improved cardiac function in I/R rat hearts, while 5-HD basically cancelled IPo’s myocardial protective effect. Joint application of two-dimensional polyacrylamide gel electrophoresis (2DE) and MALDI-TOF MS identified eight differentially expressed proteins between groups. Expression of cardiac succinate dehydrogenase (ubiquinone) flavoprotein subunit (SDHA) increased more than two-fold after I/R, while IPo led to overexpression of dihydrolipoyl dehydrogenase (DLD), NADH dehydrogenase (ubiquinone) flavoprotein 1 and isoform CRA_b (NDUFV1). When the mitoKATP was blocked, MICOS complex subunit Mic60 (IMMT) and Stress-70 protein (Grp75) were over expressed, while DLDH, ATPase subunit A (ATPA) and rCG44606 were decreased. Seven of the differential proteins belong to electron transport chain (ETC) or metabolism regulating proteins, and five of them were induced by closing mitoKATP in I/R hearts. We thus conclude that IPo’s myocardial protective effect relies on energy homeostasis regulation. DLD, SDHA, NDUFV1, Grp75, ATPA and rCG44606 may contribute to IPo’s cardial protective effect.
Revisiting nitrification in the Eastern Tropical South Pacific: A focus on controls
Authors: Peng Xuefeng , Fuchsman Clara A. , Jayakumar Amal , Warner Mark J. , Devol Allan H. , Ward Bess B.
Published: February 2016

Nitrification, the oxidation of ammonium (
) to nitrite (
) and to nitrate (
), is a component of the nitrogen (N) cycle internal to the fixed N pool. In oxygen minimum zones (OMZs), which are hotspots for oceanic fixed N loss, nitrification plays a key role because it directly supplies substrates for denitrification and anaerobic ammonia oxidation (anammox), and may compete for substrates with these same processes. However, the control of oxygen and substrate concentrations on nitrification are not well understood. We performed onboard incubations with 15N‐labeled substrates to measure rates of
and
oxidation in the eastern tropical South Pacific (ETSP). The spatial and depth distributions of
and
oxidation rates were primarily controlled by
and
availability, oxygen concentration, and light. In the euphotic zone, nitrification was partially photoinhibited. In the anoxic layer,
oxidation was negligible or below detection, but high rates of
oxidation were observed.
oxidation displayed extremely high affinity for both
and oxygen. The positive linear correlations between
oxidation rates and in situ
concentrations and ammonia monooxygenase subunit A (amoA) gene abundances in the upper oxycline indicate that the natural assemblage of ammonia oxidizers responds to in situ
concentrations or supply by adjusting their population size, which determines the
oxidation potential. The depth distribution of archaeal and bacterial amoA gene abundances and N2O concentration, along with independently reported simultaneous direct N2O production rate measurements, suggests that AOA were predominantly responsible for
oxidation, which was a major source of N2O production at oxygen concentrations > 5 µM.
The role of radiation in organizing convection in weak temperature gradient simulations
Authors: Sessions Sharon L. , Sentić Stipo , Herman Michael J.
Published: February 2016

Using a cloud system resolving model with the large scale parameterized by the weak temperature gradient approximation, we investigated the influence of interactive versus noninteractive radiation on the characteristics of convection and convective organization. The characteristics of convecting environments are insensitive to whether radiation is interactive compared to when it is not. This is not the case for nonconvecting environments; interactive radiative cooling profiles show strong cooling at the top of the boundary layer which induces a boundary layer circulation that ultimately exports moist entropy (or analogously moist static energy) from dry domains. This upgradient transport is associated with a negative gross moist stability, and it is analogous to boundary layer circulations in radiative convective equilibrium simulations of convective self‐aggregation. This only occurs when radiation cools interactively. Whether radiation is static or interactive also affects the existence of multiple equilibria‐steady states which either support precipitating convection or which remain completely dry depending on the initial moisture profile. Interactive radiation drastically increases the range of parameters which permit multiple equilibria compared to static radiation; this is consistent with the observation that self‐aggregation in radiative‐convective equilibrium simulations is more readily attained with interactive radiation. However, the existence of multiple equilibria in absence of interactive radiation suggests that other mechanisms may result in organization.
Vertebrate Neurogenesis: Cell Polarity
Authors: Zolessi Flavio R
Published: February 2016

Neurons originate from epithelial cells that, after proliferation and cell fate decisions, undergo a series of polarity transitions to achieve the differentiated state. The fate of neural progenitors depends on the interplay between cell cycle and neuroepithelial polarity by two main mechanisms: (1) asymmetric inheritance of cytoplasmic determinants, such as molecules of the apical adhesion complexes, and (2) interkinetic nuclear migration through gradients of signalling molecules such as Notch. Regarding cell fate, divisions can be symmetric or asymmetric. After a neuron is born, differentiation initiates with a downregulation of epithelial polarity, followed by cell detachment and migration, and the final acquisition of a neuronal morphology. All these transitions are based on extremely conserved molecular mechanisms, including the involvement of polarity protein complexes (such as the PAR3 complex) and small GTPases that mostly affect actin and microtubule dynamics. However, some important variations have been observed in different neuronal types and experimental conditions.

Key Concepts

Neurons are highly polarised cells that are generated from progenitors with a different kind of polarity: neuroepithelial cells.

The neuroepithelium is an embryonic tissue characterised by its pseudo‐stratified organisation, with a basal lamina, sub‐apical cadherin‐based adhesion complexes and an apical primary cilium.

The pseudo‐stratified organisation of the neuroepithelium is actively maintained by interkinetic nuclear migration, a process by which cell nuclei locate at different apicobasal positions, according to their stage in the cell cycle.

Interkinetic nuclear migration provides the neuroepithelium with the possibility of rapidly proliferating while maintaining a relatively reduced size in the embryo.

Neuroepithelial polarity and interkinetic nuclear migration favour the asymmetric distribution of signalling cues (including extracellular molecules and cytoplasmic determinants), which are essential for neurogenesis, neuronal migration and neuronal polarisation.

Neurons are post‐mitotic cells, which are born from a progenitor cell division that can be symmetric (generating two neurons) or asymmetric (generating one neuron and another progenitor cell).

After the last cell division close to the apical surface, neuroblasts must migrate to their final differentiation position, and this migration is also influenced by cell polarity cues.

Neuronal polarisation mechanisms have largely been studied using cell cultures, where neurons extend an axon after a period of radially symmetric, multipolar organisation.

In the living tissue neurons must not only polarise (form one axon and oppositely directed dendrites) but also orient properly (the axon and dendrite must be directed to the right orientation).

In vitro
, mechanisms of neuronal polarisation rely mostly on intrinsic signals, such as the asymmetric accumulation of the PAR3 complex;
in vivo
, however, these intrinsic molecules are modulated by extrinsic signals such as Laminin‐1 or N‐Cadherin.
Follicular Dendritic Cells (BLymphocyte Stimulating)
Authors: Wang Changna , Ollerton Matthew T , Burton Gregory F
Published: February 2016

Follicular dendritic cells (FDCs) are found in all secondary lymphoid tissues, where they function as a repository of antigens to maintain long‐term IgG and IgE responses. Antigens are trapped and retained on FDCs in the form of immune complexes; and while most immune complexes require large quantities to induce an immune response, FDC‐trapped antigens are remarkably immunogenic and only a few picogram can induce microgram concentrations of a specific antibody. In addition to providing antigens, FDCs provide a number of additional signals (e.g. BAFF, IL‐6) that further contribute to antibody production. In addition to their contributions to immunity in health, FDCs are involved in some pathological situations including HIV/AIDS (human immunodeficiency virus/acquired immune deficiency syndrome), sarcoma/lymphoma, prion‐mediated transmissible spongiform encephalopathies (e.g. Creutzfeldt–Jakob) and Castleman disease. A further understanding of FDCs and their functions in both health and disease may aid our ability to better regulate immunity and ameliorate some disease states.

Key Concepts

FDCs trap antigens as immune complexes that consist of antigen in the presence of either specific antibodies or complement proteins, or both. FDCs trap immune complexes using CD32 and/or CD21.

FDC‐trapped antigens or iccosomes are highly immunogenic and minute amounts (picogram) can induce significant quantities (microgram) of a specific antibody.

FDC‐trapped antigens remain on the surface of FDCs and are not internalised. These antigens are not degraded but maintain their native configuration and immunoreactivity for many months.

In addition to trapping conventional antigens, FDCs also trap HIV (and potentially other viruses) and maintain the infectious nature for many months. FDC‐trapped HIV can transmit infection to adjacent target cells (e.g. CD4+T lymphocytes).

FDCs provide both antigen and other signals that are central to the induction and maintenance of specific antibody responses.

FDCs can play roles in both health and disease (e.g. HIV/AIDS, prion diseases and follicular lymphomas).
Plant Storage Lipids
Authors: Murphy Denis J
Published: February 2016

Plant storage lipids, normally in the form of intracellular triacylglycerol‐rich droplets, are important sources of nutrition for people and livestock; besides, they supply a vast range of renewable industrial products from oleochemicals and bioplastics to paints and biofuels. Storage lipids are mainly found in plant propagules such as seeds and pollen grains, where they form an energy source for post‐germinative growth. The main commercial sources of plant storage lipids are oilseed crops such as soybean, rapeseed and maize or oil‐rich fruits such as olive or oil palm. Triacylglycerols also have several additional nonstorage functions in processes including host–pathogen interactions and abiotic stress responses. Improved knowledge of storage lipid metabolism is being used to create new oil crop varieties and to domesticate new species to supply the ever‐increasing demand for plant oils.

Key Concepts

How plants store energy reserves in the form of lipids.

What are the key storage lipids in plants.

How are plant storage lipids synthesised.

Where are store lipids made in plant cells.

What are the biotechnological uses of plant storage lipids.

How is storage lipid metabolism regulated and how can it be manipulated.
Species Richness: Small Scale
Authors: Brown Rebecca L , Reilly Lee Anne J , Peet Robert K
Published: February 2016

Species richness, defined as the number of species per unit area, is the simplest measure of biodiversity. Small‐scale species richness generally refers to species richness at the scale of a single community, habitat or microhabitat. Understanding the factors that affect and are affected by small‐scale species richness is fundamental to understanding how ecological communities are assembled and function and how biodiversity is maintained. Several factors affect small‐scale species richness, including geographic factors such as the regional species pool, dispersal distance and ease of dispersal, biological factors such as competition, facilitation, and predation as well as environmental factors such as resource availability, environmental heterogeneity and disturbance frequency and intensity. The importance of these factors varies with scale of observation. Further, small‐scale richness can impact aspects of ecosystem function including productivity, stability, and invasibility.

Key Concepts

Small‐scale species richness is the number of species per unit area at the scale of a single community, habitat or microhabitat.

Species richness is similar to alpha (α) diversity, or the number of species occurring at the local scale in a relatively homogeneous area.

Many factors affect small‐scale species richness, including geographic (e.g. species pool, dispersal), biotic (e.g. competition, predation, facilitation) and abiotic (e.g. resource availability, environmental heterogeneity, disturbance frequency and intensity).

The species pool is the set of species adapted to a site that are regionally available to colonise that site, and, in conjunction with dispersal processes, define the universe from which the ecological community is assembled.

Immigration is affected by the distance between suitable habitat sites and the ability of propagules to become established at the local site, and can significantly increase species richness.

Competition tends to decrease small‐scale richness, and its impact is shaped by resource availability, the specific resources being competed for and ecological disturbances that reduce competition.

Interactions among predators and prey, or pathogens and parasites and their hosts, can maintain or alter small‐scale diversity, the impact being largely dependent on the level of dominance of the species directly impacted.

While there is some evidence of a positive relationship between small‐scale richness and productivity, other factors such as the number and identity of functional groups may be the direct cause of the relationship.

Small‐scale richness has complex effects on the stability and invasibility of local sites.
Centrosome in Cell Division, Development and Disease
Authors: Buchwalter Rebecca A , Chen Jieyan V , Zheng Yiming , Megraw Timothy L
Published: February 2016

The centrosome is a non‐membrane‐bound organelle present in most animal cells and it functions as the major microtubule‐organising centre (MTOC). Recent findings have revealed the detailed molecular and structural features of the centrosome, and architectural and functional changes at the centrosome during the cell cycle. The centriole, the organisational heart of the centrosome, duplicates once each cell cycle and depends on a hierarchy of regulatory and assembly factors for its biogenesis. The centrosome plays important roles in dividing and nondividing cells. This importance is reflected in the appearance of several human developmental disorders when genes encoding centrosomal proteins are mutated. The centriole is essential for the formation of cilia, the cell's ‘antennae’ that receive and transmit signals and sensory inputs critical for animal development and physiology. Impairment of cilium structure or function leads to a spectrum of diseases called ciliopathies.

Key Concepts

The centrosome typically contains a centriole pair, the mother and its daughter, and the pericentriolar material (PCM).

Centrioles have a ninefold radial symmetry and are required for organising a functional centrosome.

The PCM is a large multi‐protein complex that regulates microtubule (MT) assembly at centrosomes in dividing and nondividing cells.

Centrioles duplicate only once each cell cycle, and the protein kinase PLK4 is a key early regulator of centriole duplication and biogenesis.

The cartwheel at the proximal end of the centriole is assembled early in centriole biogenesis, and its ninefold symmetry is determined by the intrinsic properties of the key structural protein Sas‐6.

The centrosome is involved in the asymmetric division of stem cells.

In nondividing cells, the basal body, a modified mother centriole, serves as a platform for organising the MT‐based axoneme, forming a primary or motile cilium.

Most vertebrate cells contain a primary cilium that is critical for signalling pathways including Hedgehog (Hh) signalling and left–right asymmetry designation during development.

Centrosomal and ciliary dysfunctions have been linked to two types of diseases: microcephaly/primordial dwarfisms, and ciliopathies, respectively.
Development of the Mammalian Gonad: Key Sex‐Determining Genes in Mice and Humans
Authors: Warr Nick , Greenfield Andy
Published: February 2016

Sex determination is the process by which an embryo commits to the male or female gonadal fate. Our understanding of mammalian sex determination is dominated by the consideration of data from humans and mouse models. Humans and mice share important elements of their reproductive biology, and therefore experimentation in the mouse offers the prospect of detailed mechanistic insights into typical and atypical human sexual development. Recent studies reveal a high degree of conservation in the roles played by sex‐determining genes in mice and humans, but also important differences. Key themes that have emerged from mouse genetics studies include the mutually antagonistic roles of testis‐ and ovary‐determining genes and the requirement to maintain these long after the primary sex‐determining event. The advent of technologies such as next‐generation sequencing and genome editing promises to shed more light on the causes of disorders of sex development in humans, as well as fundamental mechanisms in cell fate commitment in the mammalian gonad.

Key Concepts

The mammalian gonad (testis or ovary) develops from a bipotential primordium in which genes associated with later sexual differentiation are expressed.

The testis‐ and ovary‐determining gene networks are mutually antagonistic during primary sex determination.

The maintenance of cell identity in the differentiated adult gonad requires continued inhibition of opposing genetic pathways.

Interpreting the nature of mutations associated with human genetic disease, including disorders of sex development (DSD), is aided by the generation and study of mouse models.
Evolutionary Ecology of Specialisation
Authors: Vamosi Jana C , Poisot Timothée
Published: February 2016

The processes that drive the evolution of specialisation are still poorly understood. While theory generally invokes the assumption that generalists bear costs compared to species that have a less intense exploitation of specific resources, the existence of these costs have not received strong empirical support. Recent studies have broadened the dialogue by examining specialisation from a macroevolutionary perspective. Are specialist lineages transitioning towards a broader niche under certain environmental conditions, or are they limited in their evolutionary potential and doomed to eventual extinction? The overall finding is that context dependency is key to driving rapid transitions in niche dimensions and composition. Answers to these questions are fascinating in terms of better understanding the natural world and also have the potential to improve prioritisation of future conservation efforts.

Key Concepts

Many ideas about the evolution of specialisation rely on the premise that ‘Jack of all trades is master of none’, that is, generalists are locally outperformed by specialists.

Genetic or physiological trade‐offs imply that populations experience reduced performance in one function when selection results in increased performance on another function (antagonistic pleiotropy).

The evolution of specialisation depends on how often alternate hosts or environments are encountered, which depends on abundance and range extent of a species and its neighbours.

Biogeography, functional trait distributions and range limits create ‘forbidden links’ by precluding pairs of species, or a species and a particular suite of environmental variables, from coexisting.

The idea of specialisation applies equally to a species biotic and abiotic niche, yet the expectations for how specialisation may evolve for each aspect of niche may differ.

Evolutionary transitions from specialisation to generalisation are common (and vice versa), yet specialists may experience greater extinction rates due to smaller geographical range.

The evolutionary ecology of specialisation is emerging as a key component in studies of host–pathogen evolution and conservation biology.
Evidence‐based intervention against bullying and cyberbullying: Evaluation of the NoTrap! program in two independent trials
Authors: Palladino Benedetta E. , Nocentini Annalaura , Menesini Ersilia
Published: February 2016

The NoTrap! (Noncadiamointrappola!) program is a school‐based intervention, which utilizes a peer‐led approach to prevent and combat both traditional bullying and cyberbullying. The aim of the present study was to evaluate the efficacy of the third Edition of the program in accordance with the recent criteria for evidence‐based interventions. Towards this aim, two quasi‐experimental trials involving adolescents (age M = 14.91, SD = .98) attending their first year at different high schools were conducted. In Trial 1 (control group, n = 171; experimental group, n = 451), latent growth curve models for data from pre‐, middle‐ and post‐tests showed that intervention significantly predicted change over time in all the target variables (victimization, bullying, cybervictimization, and cyberbullying). Specifically, target variables were stable for the control group but decreased significantly over time for the experimental group. Long‐term effects at the follow up 6 months later were also found. In Trial 2 (control group, n = 227; experimental group, n = 234), the moderating effect of gender was examined and there was a reported decrease in bullying and cyberbullying over time (pre‐ and post‐test) in the experimental group but not the control group, and this decrease was similar for boys and girls. Aggr. Behav. 42:194–206, 2016. © 2016 Wiley Periodicals, Inc.
Comparison of the Utility and Validity of Three Scoring Tools to Measure Skin Involvement in Patients With Juvenile Dermatomyositis
Authors: Campanilho‐Marques Raquel , Almeida Beverley , Deakin Claire , Arnold Katie , Gallot Natacha , de Iorio Maria , Nistala Kiran , Pilkington Clarissa A. , Wedderburn Lucy R. ,   on behalf of the Juvenile Dermatomyositis Research Group
Published: February 2016

Objective

To compare the abbreviated Cutaneous Assessment Tool (CAT), Disease Activity Score (DAS), and Myositis Intention to Treat Activity Index (MITAX) and correlate them with the physician's 10‐cm skin visual analog scale (VAS) in order to define which tool best assesses skin disease in patients with juvenile dermatomyositis.

Methods

A total of 71 patients recruited to the UK Juvenile Dermatomyositis Cohort and Biomarker Study were included and assessed for skin disease using the CAT, DAS, MITAX, and skin VAS. The Childhood Myositis Assessment Scale (CMAS), manual muscle testing of 8 groups (MMT8), muscle enzymes, inflammatory markers, and physician's global VAS were recorded. Relationships were evaluated using Spearman's correlations and predictors with linear regression. Interrater reliability was assessed using intraclass correlation coefficients.

Results

All 3 tools showed correlation with the physician's global VAS and skin VAS, with DAS skin showing the strongest correlation with skin VAS. DAS skin and CAT activity were inversely correlated with CMAS and MMT8, but these correlations were moderate. No correlations were found between the skin tools and inflammatory markers or muscle enzymes. DAS skin and CAT were the quickest to complete (mean ± SD 0.68 ± 0.1 minutes and 0.63 ± 0.1 minutes, respectively).

Conclusion

The 3 skin tools were quick and easy to use. The DAS skin correlated best with the skin VAS. The addition of CAT in a bivariate model containing the physician's global VAS was a statistically significant estimator of skin VAS score. We propose that there is scope for a new skin tool to be devised and tested, which takes into account the strengths of the 3 existing tools.
Printed Carbon Nanotube Electronics and Sensor Systems
Authors: Chen Kevin , Gao Wei , Emaminejad Sam , Kiriya Daisuke , Ota Hiroki , Nyein Hnin Yin Yin , Takei Kuniharu , Javey Ali
Published: February 2016

Printing technologies offer large‐area, high‐throughput production capabilities for electronics and sensors on mechanically flexible substrates that can conformally cover different surfaces. These capabilities enable a wide range of new applications such as low‐cost disposable electronics for health monitoring and wearables, extremely large format electronic displays, interactive wallpapers, and sensing arrays. Solution‐processed carbon nanotubes have been shown to be a promising candidate for such printing processes, offering stable devices with high performance. Here, recent progress made in printed carbon nanotube electronics is discussed in terms of materials, processing, devices, and applications. Research challenges and opportunities moving forward from processing and system‐level integration points of view are also discussed for enabling practical applications.
Metastabiles Salpetersäuretrihydrat in Eiswolken
Authors: Weiss Fabian , Kubel Frank , Gálvez Óscar , Hoelzel Markus , Parker Stewart F. , Baloh Philipp , Iannarelli Riccardo , Rossi Michel J. , Grothe Hinrich
Published: February 2016

Die Zusammensetzung von hochliegenden Eiswolken ist ein intensiv diskutierter Gegenstand der aktuellen Forschung. Die Bildungsmechanismen und die genaue Phasenzusammensetzung sind, nicht zuletzt aufgrund der schwierigen Zugänglichkeit, noch nicht endgültig aufgeklärt. Hier wird eine lange vermutete, aber strukturell unbekannte Phase vorgestellt. Diese Phase ist alpha‐Salpetersäuretrihydrat (alpha‐NAT), eine metastabile Phase von NAT. Mittels Röntgen‐ und Neutronendiffraktionsexperimenten wurde die Phase analysiert und daraus eine schlüssige Struktur abgeleitet. Schwingungsspektren wurden aufgenommen und mit theoretischen Berechnungen verglichen. Es konnte eine starke Interaktion zwischen Eis und alpha‐NAT beobachtet werden, was die experimentellen Spektren und die Kinetik beim Phasenübergang erklärt. Auf Grundlage der ermittelten Ergebnisse wird ein dreistufiger Prozess zur Bildung von NAT in stratosphärischen Wolken vorgeschlagen.
Mild Cobalt‐Catalyzed Negishi Cross‐Couplings of (Hetero)arylzinc Reagents with (Hetero)aryl Halides
Authors: Haas Diana , Hammann Jeffrey M. , Lutter Ferdinand H. , Knochel Paul
Published: February 2016

A catalytic system consisting of CoCl2⋅2 LiCl (5 mol %) and HCO2Na (50 mol %) enables the cross‐coupling of various N‐heterocyclic chlorides and bromides as well as aromatic halogenated ketones with various electron‐rich and ‐poor arylzinc reagents. The reactions reached full conversion within a few hours at 25 °C.
Multifunctional Antioxidants: Regenerable Radical‐Trapping and Hydroperoxide‐Decomposing Ebselenols
Authors: Kumar Shailesh , Yan Jiajie , Poon Jia‐fei , Singh Vijay P. , Lu Xi , Karlsson Ott Marjam , Engman Lars , Kumar Sangit
Published: February 2016

Regenerable, multifunctional ebselenol antioxidants were prepared that could quench peroxyl radicals more efficiently than α‐tocopherol. These compounds act as better mimics of the glutathione peroxidase enzymes than ebselen. Production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in human mononuclear cells was considerably decreased upon exposure to the organoselenium compounds. At a concentration of 25 μm, the ebselenol derivatives showed minimal toxicity in pre‐osteoblast MC3T3 cells.
The Effect of Hydrophile Topology in RAFT‐Mediated Polymerization‐Induced Self‐Assembly
Authors: Lesage de la Haye Jennifer , Zhang Xuewei , Chaduc Isabelle , Brunel Fabrice , Lansalot Muriel , D'Agosto Franck
Published: February 2016

Polymerization‐induced self‐assembly (PISA) was employed to compare the self‐assembly of different amphiphilic block copolymers. They were obtained by emulsion polymerization of styrene in water using hydrophilic poly(N‐acryloylmorpholine) (PNAM)‐based macromolecular RAFT agents with different structures. An average of three poly (ethylene glycol acrylate) (PEGA) units were introduced either at the beginning, statistically, or at the end of a PNAM backbone, resulting in formation of nanometric vesicles and spheres from the two former macroRAFT architectures, and large vesicles from the latter. Compared to the spheres obtained with a pure PNAM macroRAFT agent, composite macroRAFT architectures promoted a dramatic morphological change. The change was induced by the presence of PEGA hydrophilic side‐chains close to the hydrophobic polystyrene segment.
TiO2 Nanotubes: Nitrogen‐Ion Implantation at Low Dose Provides Noble‐Metal‐Free Photocatalytic H2‐Evolution Activity
Authors: Zhou Xuemei , Häublein Volker , Liu Ning , Nguyen Nhat Truong , Zolnhofer Eva M. , Tsuchiya Hiroaki , Killian Manuela S. , Meyer Karsten , Frey Lothar , Schmuki Patrik
Published: February 2016

Low‐dose nitrogen implantation induces an ion and damage profile in TiO2 nanotubes that leads to “co‐catalytic” activity for photocatalytic H2‐evolution (without the use of any noble metal). Ion implantation with adequate parameters creates this active zone limited to the top part of the tubes. The coupling of this top layer and the underlying non‐implanted part of the nanotubes additionally contributes to an efficient carrier separation and thus to a significantly enhanced H2 generation.
Reduced DICER1 Expression Bestows Rheumatoid Arthritis Synoviocytes Proinflammatory Properties and Resistance to Apoptotic Stimuli
Authors: Alsaleh Ghada , Nehmar Ramzi , Blüml Stephan , Schleiss Cédric , Ostermann Eleonore , Dillenseger Jean‐Philippe , Sayeh Amira , Choquet Philippe , Dembele Doulaye , Francois Antoine , Salmon Jean‐Hugues , Paul Nicodème , Schabbauer Gernot , Bierry Guillaume , Meyer Alain , Gottenberg Jacques‐Eric , Haas Gabrielle , Pfeffer Sebastien , Vallat Laurent , Sibilia Jean , Bahram Seiamak , Georgel Philippe
Published: February 2016

Objective

While the regulatory role of individual microRNAs (miRNAs) in rheumatoid arthritis (RA) is well established, the role of DICER1 in the pathogenesis of the disease has not yet been investigated. The purpose of this study was to analyze the expression of factors involved in miRNA biogenesis in fibroblast‐like synoviocytes (FLS) from RA patients and to monitor the arthritis triggered by K/BxN serum transfer in mice deficient in the Dicer gene (Dicerd/d).

Methods

The expression of genes and precursor miRNAs was quantified by quantitative reverse transcription–polymerase chain reaction (qRT‐PCR). MicroRNA macroarray profiling was monitored by qRT‐PCR. Cytokines were quantified by enzyme‐linked immunosorbent assay. Experimental arthritis in mice was achieved by the transfer of serum from K/BxN donors. Apoptosis was quantified using an enzyme‐linked immunosorbent assay.

Results

We found decreased DICER1 and mature miRNA expression in synovial fibroblasts from RA patients. These cells were hyperresponsive to lipopolysaccharide, as evidenced by their increased interleukin‐6 secretion upon stimulation. Experimental serum‐transfer arthritis in Dicerd/d mice confirmed that an unbalanced biogenesis of miRNAs correlated with an enhanced inflammatory response. Synoviocytes from both RA patients and Dicerd/d mice exhibited increased resistance to apoptotic stimuli.

Conclusion

The findings of this study further substantiate the important role of DICER1 in the maintenance of homeostasis and the regulation of inflammatory responses.
Facile Synthesis of Porous Dendritic Bimetallic Platinum–Nickel Nanocrystals as Efficient Catalysts for the Oxygen Reduction Reaction
Authors: Eid Kamel , Wang Hongjing , Malgras Victor , Alothman Zeid Abdullah , Yamauchi Yusuke , Wang Liang
Published: February 2016

Certain bimetallic nanocrystals (NCs) possess promising catalytic properties for electrochemical energy conversion. Herein, we report a facile method for the one‐step synthesis of porous dendritic PtNi NCs in aqueous solution at room temperature that contrasts with the traditional multistep thermal decomposition approach. The dendritic PtNi NCs assembled by interconnected arms are efficient catalysts for the oxygen reduction reaction. This direct and efficient method is favorable for the up‐scaled synthesis of active catalysts used in electrochemical applications.
Interaction between MTHFR 677C>T and periconceptional folic acid supplementation in the risk of Hypospadias
Authors: Dokter Elisabeth M.J. , van Rooij Iris A.L.M. , Wijers Charlotte H.W. , Groothuismink Johanne M. , van der Biezen Jan Jaap , Feitz Wout F.J. , Roeleveld Nel , van der Zanden Loes F.M.
Published: February 2016

Background

Hypospadias is a congenital malformation with both environmental factors and genetic predisposition involved in the pathogenesis. The role of maternal periconceptional folic acid supplement use in the development of hypospadias is unclear. As folate levels may also be influenced by the C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene, we hypothesize that a gene–environment interaction between this polymorphism and folic acid use is involved in the etiology of hypospadias.

Methods

We conducted a case–control study among 855 hypospadias cases and 713 population‐based controls from the AGORA data‐ and biobank. Folic acid supplement use was derived from maternal questionnaires and infant and maternal DNA was used to determine the MTHFR C677T polymorphism using Taqman assays. We performed separate analyses for different hypospadias phenotypes (anterior/middle/posterior).

Results

Hypospadias was neither associated with folic acid use or the MTHFR C677T polymorphism, nor with their interaction. However, we did find an association with middle hypospadias when no supplements were used (odds ratio = 1.6; 95% confidence interval, 1.1–2.4), especially in infants carrying the CT/TT genotype (odds ratio = 2.5; 95% confidence interval, 1.4–4.7). In addition, more infants with these genotypes seemed to have posterior hypospadias, regardless of folic acid use.

Conclusion

Our study does not suggest a major role for folic acid supplements or the MTHFR C677T polymorphism in the etiology of hypospadias in general, but not using folic acid and/or carrying the MTHFR C677T polymorphism may be associated with middle and posterior hypospadias. Therefore, we stress the importance of studying gene–environment interactions preferably in stratified analyses for different hypospadias phenotypes. Birth Defects Research (Part A) 106:275–284, 2016. © 2016 Wiley Periodicals, Inc.