bluuebunny/crossref_metadata_2025 huggingface dataset:
MECP2 regulates cortical plasticity underlying a learned behavior in adult female mice
Authors: Krishnan Keerthi , Lau Billy Y. B. , Ewall Gabrielle , Huang Z. Josh , Shea Stephen D.
Published: February 2016

Neurodevelopmental disorders begin with the emergence of inappropriate synaptic connectivity early in life, yet how the sustained disruption of experience-dependent plasticity aggravates symptoms in adulthood is unclear. Here we used pup retrieval learning to assay adult cortical plasticity in a female mouse model of Rett syndrome (MeCP2het). We show that auditory cortical plasticity and retrieval learning are impaired inMeCP2het. Specifically, normal MECP2 expression in the adult auditory cortex is required for efficient retrieval learning. In wild-type mice, cohabitation with a mother and her pups triggered transient changes to auditory cortical inhibitory networks, including elevated levels of the GABA-synthesizing enzyme GAD67. However,MeCP2hetfurther exhibited increased expression of parvalbumin (PV) and perineuronal nets (PNNs), events thought to suppress plasticity at the closure of critical periods and in adult learning. Averting these events with genetic and pharmacological manipulations of the GABAergic network restored retrieval behavior. We propose that adult retrieval learning triggers a transient episode of inhibitory plasticity in the auditory cortex that is dysregulated inMeCP2het. This window of heightened sensitivity to social sensory cues reveals a role ofMeCP2mutations in facilitating adult plasticity that is distinct from their effects on early development.
A novel polytype – the stacking fault based γ-MoO3nanobelts
Authors: Sławiński Wojciech A. , Fjellvåg Øystein S. , Ruud Amund , Fjellvåg Helmer
Published: February 2016

γ-MoO3nanobelts prepared by hydrothermal synthesis were studied by synchrotron radiation powder diffraction, scanning electron microscopy, transmission electron microscopy and selected area electron diffraction. Their nm dimensions, in particular in two crystallographic directions, have a profound influence on electrochemical properties during cycling as the cathode material in lithium-ion batteries (LIBs). The diffraction analysis shows clearly that the crystal structure for the γ-MoO3nanobelts differs significantly from that of bulk α-MoO3. The observed powder diffraction pattern, with asymmetric peaks, extremely broad peaks, as well as additional or absent diffraction peaks, is fully described by means of a model based on stacking disorder of MoO3slabs.
Synthesis and crystal structure of the dinuclear copper(II) Schiff base complex μ-hydroxido-μ-chlorido-bis{[bis(trans-2-nitrocinnamaldehyde)ethylenediamine]chloridocopper(II)} dichloromethane sesquisolvate
Authors: Barati Kazem , Clegg William , Habibi Mohammad Hossein , Harrington Ross W. , Lalegani Arash , Montazerozohori Morteza
Published: February 2016

Transition metal complexes of Schiff base ligands have been shown to have particular application in catalysis and magnetism. The chemistry of copper complexes is of interest owing to their importance in biological and industrial processes. The reaction of copper(I) chloride with the bidentate Schiff baseN,N′-bis(trans-2-nitrocinnamaldehyde)ethylenediamine {Nca2en, systematic name: (1E,1′E,2E,2′E)-N,N′-(ethane-1,2-diyl)bis[3-(2-nitrophenyl)prop-2-en-1-imine]} in a 1:1 molar ratio in dichloromethane without exclusion of air or moisture resulted in the formation of the title complex μ-chlorido-μ-hydroxido-bis(chlorido{(1E,1′E,2E,2′E)-N,N′-(ethane-1,2-diyl)bis[3-(2-nitrophenyl)prop-2-en-1-imine]-κ2N,N′}copper(II)) dichloromethane sesquisolvate, [Cu2Cl3(OH)(C20H18N4O4)2]·1.5CH2Cl2. The dinuclear complex has a folded four-membered ring in an unsymmetrical Cu2OCl3core in which the approximate trigonal bipyramidal coordination displays different angular distortions in the equatorial planes of the two CuIIatoms; the chloride bridge is asymmetric, but the hydroxide bridge is symmetric. The chelate rings of the two Nca2en ligands have different conformations, leading to a more marked bowing of one of the ligands compared with the other. This is the first reported dinuclear complex, and the first five-coordinate complex, of the Nca2en Schiff base ligand. Molecules of the dimer are associated in pairs by ring-stacking interactions supported by C—H...Cl interactions with solvent molecules; a further ring-stacking interaction exists between the two Schiff base ligands of each molecule.
Data collection with a tailored X-ray beam size at 2.69 Å wavelength (4.6 keV): sulfur SAD phasing of Cdc23Nterm
Authors: Cianci Michele , Groves Matthew R. , Barford David , Schneider Thomas R.
Published: February 2016

The capability to reach wavelengths of up to 3.1 Å at the newly established EMBL P13 beamline at PETRA III, the new third-generation synchrotron at DESY in Hamburg, provides the opportunity to explore very long wavelengths to harness the sulfur anomalous signal for phase determination. Data collection at λ = 2.69 Å (4.6 keV) allowed the crystal structure determination by sulfur SAD phasing of Cdc23Nterm, a subunit of the multimeric anaphase-promoting complex (APC/C). At this energy, Cdc23Ntermhas an expected Bijvoet ratio 〈|Fanom|〉/〈F〉 of 2.2%, with 282 residues, including six cysteines and five methionine residues, and two molecules in the asymmetric unit (65.4 kDa; 12 Cys and ten Met residues). Selectively illuminating two separate portions of the same crystal with an X-ray beam of 50 µm in diameter allowed crystal twinning to be overcome. The crystals diffracted to 3.1 Å resolution, with unit-cell parametersa=b= 61.2,c = 151.5 Å, and belonged to space groupP43. The refined structure to 3.1 Å resolution has anRfactor of 18.7% and anRfreeof 25.9%. This paper reports the structure solution, related methods and a discussion of the instrumentation.
A history of experimental phasing in macromolecular crystallography
Authors: Isaacs Neil
Published: February 2016

It was just over a century ago that W. L. Bragg published a paper describing the first crystal structures to be determined using X-ray diffraction data. These structures were obtained from considerations of X-ray diffraction (Bragg equation), crystallography (crystal lattices and symmetry) and the scattering power of different atoms. Although W. H. Bragg proposed soon afterwards, in 1915, that the periodic electron density in crystals could be analysed using Fourier transforms, it took some decades before experimental phasing methods were developed. Many scientists contributed to this development and this paper presents the author's own perspective on this history. There will be other perspectives, so what follows isahistory, rather thanthehistory, of experimental phasing.
Can I solve my structure by SAD phasing? Planning an experiment, scaling data and evaluating the useful anomalous correlation and anomalous signal
Authors: Terwilliger Thomas C. , Bunkóczi Gábor , Hung Li-Wei , Zwart Peter H. , Smith Janet L. , Akey David L. , Adams Paul D.
Published: February 2016

A key challenge in the SAD phasing method is solving a structure when the anomalous signal-to-noise ratio is low. Here, algorithms and tools for evaluating and optimizing the useful anomalous correlation and the anomalous signal in a SAD experiment are described. A simple theoretical framework [Terwilligeret al.(2016),Acta Cryst.D72, 346–358] is used to develop methods for planning a SAD experiment, scaling SAD data sets and estimating the useful anomalous correlation and anomalous signal in a SAD data set. Thephenix.plan_sad_experimenttool uses a database of solved and unsolved SAD data sets and the expected characteristics of a SAD data set to estimate the probability that the anomalous substructure will be found in the SAD experiment and the expected map quality that would be obtained if the substructure were found. Thephenix.scale_and_mergetool scales unmerged SAD data from one or more crystals using local scaling and optimizes the anomalous signal by identifying the systematic differences among data sets, and thephenix.anomalous_signaltool estimates the useful anomalous correlation and anomalous signal after collecting SAD data and estimates the probability that the data set can be solved and the likely figure of merit of phasing.
Using selenomethionyl derivatives to assign sequence in low-resolution structures of the AP2 clathrin adaptor
Authors: Kelly Bernard T. , Graham Stephen C. , Owen David J.
Published: February 2016

Selenomethionine incorporation is a powerful technique for assigning sequence to regions of electron density at low resolution. Genetic introduction of methionine point mutations and the subsequent preparation and crystallization of selenomethionyl derivatives permits unambiguous sequence assignment by enabling the placement of the anomalous scatterers (Se atoms) thus introduced. Here, the use of this approach in the assignment of sequence in a part of the AP2 clathrin adaptor complex that is responsible for clathrin binding is described. AP2 plays a pivotal role in clathrin-mediated endocytosis, a tightly regulated process in which cell-surface transmembrane proteins are internalized from the plasma membrane by incorporation into lipid-enclosed transport vesicles. AP2 binds cargo destined for internalization and recruits clathrin, a large trimeric protein that helps to deform the membrane to produce the transport vesicle. By selenomethionine labelling of point mutants, it was shown that the clathrin-binding site is buried within a deep cleft of the AP2 complex. A membrane-stimulated conformational change in AP2 releases the clathrin-binding site from autoinhibition, thereby linking clathrin recruitment to membrane localization.
Radiation-damage-induced phasing: a case study using UV irradiation with light-emitting diodes
Authors: de Sanctis Daniele , Zubieta Chloe , Felisaz Franck , Caserotto Hugo , Nanao Max H.
Published: February 2016

Exposure to X-rays, high-intensity visible light or ultraviolet radiation results in alterations to protein structure such as the breakage of disulfide bonds, the loss of electron density at electron-rich centres and the movement of side chains. These specific changes can be exploited in order to obtain phase information. Here, a case study using insulin to illustrate each step of the radiation-damage-induced phasing (RIP) method is presented. Unlike a traditional X-ray-induced damage step, specific damage is introducedviaultraviolet light-emitting diodes (UV-LEDs). In contrast to UV lasers, UV-LEDs have the advantages of small size, low cost and relative ease of use.
Initiating heavy-atom-based phasing by multi-dimensional molecular replacement
Authors: Pedersen Bjørn Panyella , Gourdon Pontus , Liu Xiangyu , Karlsen Jesper Lykkegaard , Nissen Poul
Published: February 2016

To obtain an electron-density map from a macromolecular crystal the phase problem needs to be solved, which often involves the use of heavy-atom derivative crystals and concomitant heavy-atom substructure determination. This is typically performed by dual-space methods, direct methods or Patterson-based approaches, which however may fail when only poorly diffracting derivative crystals are available. This is often the case for, for example, membrane proteins. Here, an approach for heavy-atom site identification based on a molecular-replacement parameter matrix (MRPM) is presented. It involves ann-dimensional search to test a wide spectrum of molecular-replacement parameters, such as different data sets and search models with different conformations. Results are scored by the ability to identify heavy-atom positions from anomalous difference Fourier maps. The strategy was successfully applied in the determination of a membrane-protein structure, the copper-transporting P-type ATPase CopA, when other methods had failed to determine the heavy-atom substructure. MRPM is well suited to proteins undergoing large conformational changes where multiple search models should be considered, and it enables the identification of weak but correct molecular-replacement solutions with maximum contrast to prime experimental phasing efforts.
Phasing and structure of bestrophin-1: a case study in the use of heavy-atom cluster compounds with multi-subunit transmembrane proteins
Authors: Kane Dickson Veronica
Published: February 2016

The purification and three-dimensional crystallization of membrane proteins are commonly affected by a cumulation of pathologies that are less prevalent in their soluble counterparts. This may include severe anisotropy, poor spot shape, poor to moderate-resolution diffraction, crystal twinning, translational pseudo-symmetry and poor uptake of heavy atoms for derivatization. Such challenges must be circumvented by adaptations in the approach to crystallization and/or phasing. Here, an example of a protein that exhibited all of the above-mentioned complications is presented. Bestrophin-1 is a eukaryotic calcium-activated chloride channel, the structure of which was recently determined in complex with monoclonal antibody fragments using SAD phasing with tantalum bromide clusters (Ta6Br12·Br2). Some of the obstacles to obtaining improved diffraction and phasing for this particular channel are discussed, as well as the approach and adaptations that were key to determining the structure.
Facilitating best practices in collecting anomalous scattering data forde novostructure solution at the ESRF Structural Biology Beamlines
Authors: de Sanctis Daniele , Oscarsson Marcus , Popov Alexander , Svensson Olof , Leonard Gordon
Published: February 2016

The constant evolution of synchrotron structural biology beamlines, the viability of screening protein crystals for a wide range of heavy-atom derivatives, the advent of efficient protein labelling and the availability of automatic data-processing and structure-solution pipelines have combined to makede novostructure solution in macromolecular crystallography a less arduous task. Nevertheless, the collection of diffraction data of sufficient quality for experimental phasing is still a difficult and crucial step. Here, some examples of good data-collection practice for projects requiring experimental phasing are presented and recent developments at the ESRF Structural Biology beamlines that have facilitated these are illustrated.
Progress in low-resolutionab initiophasing withCrowdPhase
Authors: Jorda Julien , Sawaya Michael R. , Yeates Todd O.
Published: February 2016

Ab initiophasing by direct computational methods in low-resolution X-ray crystallography is a long-standing challenge. A common approach is to consider it as two subproblems: sampling of phase space and identification of the correct solution. While the former is amenable to a myriad of search algorithms, devising a reliable target function for the latter problem remains an open question. Here, recent developments inCrowdPhase, a collaborative online game powered by a genetic algorithm that evolves an initial population of individuals with random genetic make-up (i.e.random phases) each expressing a phenotype in the form of an electron-density map, are presented. Success relies on the ability of human players to visually evaluate the quality of these maps and, following a Darwinian survival-of-the-fittest concept, direct the search towards optimal solutions. While an initial study demonstrated the feasibility of the approach, some important crystallographic issues were overlooked for the sake of simplicity. To address these, the newCrowdPhaseincludes consideration of space-group symmetry, a method for handling missing amplitudes, the use of a map correlation coefficient as a quality metric and a solvent-flattening step. Performances of this installment are discussed for two low-resolution test cases based onbona fidediffraction data.
Sentiment-based predictions of housing market turning points with Google trends
Authors: Dietzel Marian Alexander
Published: February 2016

Purpose

– Recent research has found significant relationships between internet search volume and real estate markets. This paper aims to examine whether Google search volume data can serve as a leading sentiment indicator and are able to predict turning points in the US housing market. One of the main objectives is to find a model based on internet search interest that generates reliable real-time forecasts.

Design/methodology/approach

– Starting from seven individual real-estate-related Google search volume indices, a multivariate probit model is derived by following a selection procedure. The best model is then tested for its in- and out-of-sample forecasting ability.

Findings

– The results show that the model predicts the direction of monthly price changes correctly, with over 89 per cent in-sample and just above 88 per cent in one to four-month out-of-sample forecasts. The out-of-sample tests demonstrate that although the Google model is not always accurate in terms of timing, the signals are always correct when it comes to foreseeing an upcoming turning point. Thus, as signals are generated up to six months early, it functions as a satisfactory and timely indicator of future house price changes.

Practical implications

– The results suggest that Google data can serve as an early market indicator and that the application of this data set in binary forecasting models can produce useful predictions of changes in upward and downward movements of US house prices, as measured by the Case–Shiller 20-City House Price Index. This implies that real estate forecasters, economists and policymakers should consider incorporating this free and very current data set into their market forecasts or when performing plausibility checks for future investment decisions.

Originality/value

– This is the first paper to apply Google search query data as a sentiment indicator in binary forecasting models to predict turning points in the housing market.
Analysis of manufacturing strategy in developing countries
Authors: Ehie Ike , Muogboh Obinna
Published: February 2016

Purpose

– The purpose of this paper is to formulate the manufacturing strategy in a developing country with particular reference to Nigeria in sub-Saharan African country.

Design/methodology/approach

– Using survey methodology and the partial least squares – structural equation modeling technique, The authors find that in addition to the four basic environmental factors – business cost, labor availability, competitive hostility and environmental dynamism, both government policies and the adopted manufacturing practices have significant effects on the manufacturing strategic priorities.

Findings

– Among other findings, the environmental factors of government policies and the type of manufacturing practices adopted have significant effects on manufacturing strategy.

Research limitations/implications

– Further studies should explicitly look into the effect of the adopted manufacturing strategy on company performance. Possibly, a case study research might be considered to establish this relationship.

Practical implications

– As manufacturing firms continue to experience greater competition, especially from China, and given the technological advancement in manufacturing, the business environment facing Nigerian manufacturing companies is likely to become more dynamic, complex, diverse and even hostile. Under such a turbulent climate, the configuration and effective deployment of manufacturing strategies is imperative to achieving superior business performance.

Social implications

– A more effective strategy will make companies more competitive in the market place, thus creating employment in a sector that has witnessed declining growth in employment.

Originality/value

– The linkage between environmental factors and manufacturing strategy has been studied widely. However, this study reveals the role of government policies and manufacturing practices in formulating manufacturing strategy in a developing country context.
Closed-loop supply chain network equilibrium model and its Newton method
Authors: Xu Hongru , Cao Erbao
Published: February 2016

Purpose

– The purpose of this paper is to develop a closed-loop supply chain (CLSC) network equilibrium model which consists of manufactures, retailers and consumer markets engaged in a Cournot pricing game with heterogeneous multi-product.

Design/methodology/approach

– The authors model the optimal behavior of the various decision makers and CLSC network equilibrium, and derive the equilibrium conditions based on variational inequality approach. The authors present a new Newton method to solve the proposed model.

Findings

– The authors find that the algorithm converges to the solution rapidly for most cases. Besides, the authors discuss the effect of some parameters on the equilibrium solution of the model, and give some insights for policy makers, such as improving the technology level of the manufacturer, reducing the cost of waste disposal and increase the minimum ration of used product to total quantity.

Originality/value

– The authors derive the network equilibrium conditions by the variational inequality formulation in order to obtain the computation of the equilibrium flows and prices. The authors present a new Newton method to solve the proposed model. The authors discuss the effect of some parameters on the equilibrium solution of the model, and give some managerial insights
Using citizen‐collected wildlife sightings to predict traffic strike hot spots for threatened species: a case study on the southern cassowary
Authors: Dwyer Ross G. , Carpenter‐Bundhoo Luke , Franklin Craig E. , Campbell Hamish A.
Published: February 2016

Assessing the causal factors underpinning the distribution and abundance of wildlife road‐induced mortality can be challenging. This is particularly ubiquitous for rare or elusive species, because traffic strikes occur infrequently for these populations and information about localized abundance, distribution and movements are generally lacking. Here, we assessed whether citizen‐collected sightings data may serve as a low cost and efficient means of gathering long‐term animal roadside presence and road‐crossing information, which could then be used to assess the causative factors and direct mitigation actions aimed at reducing wildlife traffic strike frequency.

We explored this principle using two decades of traffic strike records and citizen‐collected sightings of the southern cassowary Casuarius casuarius johnsonii. Roads have bisected the cassowaries’ rain forest habitat and despite considerable investment into mitigation strategies for this species, road‐induced mortality is considered one of the primary threatening processes affecting the population.

Using a Bayesian approach and controlling for spatial autocorrelation with conditional autoregressive models, we demonstrate that traffic strikes are primarily a density‐dependent process in the southern cassowary. That is, traffic strike clusters occurred along stretches of road where cassowaries were most frequently sighted. There were, however, road stretches where traffic strike frequency was greater than predicted by the number of roadside sightings, illustrating when and where density‐independent processes increased the mortality potential for a road‐crossing cassowary.

Synthesis and applications. This is the first time that citizen‐collected sightings data have been used to systematically inform upon the abundance and distribution of wildlife traffic strike. The technique not only predicts where incidents are likely to occur but also helps us to understand the factors responsible for strike clustering. While not a replacement for systematic surveys, we highlight citizen‐collected sightings data as a low‐cost option when assessing contributing factors to vehicle‐induced mortality. Accounting for density‐dependent and density‐independent processes will ensure the most effective allocation of resources when implementing wildlife traffic strike mitigation.
Inflammatory bowel disease in pregnancy: a population‐based study of prevalence and pregnancy outcomes
Authors: Shand AW , Chen JS , Selby W , Solomon M , Roberts CL
Published: February 2016

Objective

To determine the prevalence of the inflammatory bowel diseases (IBD), ulcerative colitis (UC) and Crohn's disease (CD), in pregnant women and determine pregnancy and fetal/neonatal outcomes.

Design

Population‐based cohort study.

Setting

New South Wales, Australia, 2001–11.

Population

A total of 630 742 women who delivered at ≥20 weeks of gestation.

Methods

Descriptive and multivariate regression analyses of perinatal data linked to hospital admission data. We compared birth outcomes of women with and without a documented diagnosis of IBD.

Main outcome measures

Caesarean section, severe maternal morbidity, preterm birth <37 weeks of gestation, planned preterm birth, small‐for‐gestational‐age (birthweight <10th centile), perinatal mortality (stillbirth/neonatal death ≤28 days).

Results

In all, 1960 women (0.31%) with IBD, who had 2781 births (1183 UC, 1287 CD and 311 IBD‐indeterminate). Women with IBD were more likely than women without IBD to have a caesarean section [41.5 versus 28.2%, adjusted risk ratio (aRR) 1.38, 95% CI 1.31–1.45], severe maternal morbidity (2.6 versus 1.6%, aRR 1.54, 95% CI 1.17–2.03), preterm birth (9.7 versus 6.6%, aRR 1.47, 95% CI 1.30–1.66), planned preterm birth (5.3 versus 2.9%, aRR 1.74, 95% CI 1.47–2.07), and their infants to be small‐for‐gestational‐age (9.7 versus 9.5%, aRR 1.19, 95% CI 1.04–1.36). There was no evidence of a difference in perinatal mortality.

Conclusion

Pregnancy‐associated IBD is more common than previously reported. Pregnancies complicated by IBD at or near the time of birth have significantly higher rates of adverse pregnancy outcomes than pregnancies of women without IBD.

Tweetable abstract

Increased rates preterm birth and caesarean section in women with inflammatory bowel disease.
Incidence and occupational variation of ovarian granulosa cell tumours in Finland, Iceland, Norway and Sweden during 1953–2012: a longitudinal cohort study
Authors: Bryk S , Pukkala E , Martinsen J‐I , Unkila‐Kallio L , Tryggvadottir L , Sparén P , Kjærheim K , Weiderpass E , Riska A
Published: February 2016

Objective

To determine the incidence and occupational variation of granulosa cell tumours (GCTs) in Finland, Iceland, Norway and Sweden over a 60‐year period, 1953–2012.

Design

A longitudinal cohort study.

Setting and population

Finland, Iceland, Norway and Sweden and a total of 249 million women over a 60‐year period (1953–2012). The NOCCA (Nordic Occupational Cancer Study) included 6.4 million women with 776 incident GCT cases diagnosed until the end of follow up.

Methods

Incidence rates were calculated from the national cancer registries and compared using quasi‐Poisson regression models. Occupation‐specific standardised incidence ratios (SIRs) were calculated from the Nordic Occupational Cancer (NOCCA) database.

Main outcome measures

Incidence rates and standardised incidence ratios.

Results

The age‐adjusted (World Standard) incidence rates remained quite constant: about 0.6–0.8 per 100 000 for most of the study period. The age‐specific incidence was highest at 50–64 years of age. There were no occupations with significantly increased risk of GCT. Major changes in the use of oral contraceptives, postmenopausal hormonal therapy, fertility rate and lifestyle in general during the study period and among different occupational categories do not appear to have a marked effect on the incidence of GCT.

Conclusion

Our findings support the concept of GCT as a primarily sporadic, not exposure‐related, cancer.

Tweetable abstract

The Nordic incidence rates of GCTs show stability over time and among different occupational categories.
Forensic Investigation of Formaldehyde in Illicit Products for Hair Treatment by DAD‐HPLC: A Case Study
Authors: Oiye Erica N. , Ribeiro Maria Fernanda M. , Okumura Leonardo L. , Saczk Adelir A. , Ciancaglini Pietro , de Oliveira Marcelo F.
Published: February 2016

The illegal use of formalin (commercial formaldehyde) in cosmetic products harms the health of individuals exposed to this substance. Over the last years, the commercial availability of these products, especially those containing irregular dosage of formaldehyde, has increased in Brazil. This work analyzes some products for hair treatment available in the Brazilian market and verifies their safety. The adopted analytical methodology involved sample derivatization with 2,4‐dinitrophenylhydrazine, followed by high‐performance liquid chromatography with ultraviolet detection (UV–VIS) at λ = 365 nm. The limit of quantification is 2.5 × 10−3% w/w, and the recovery tests were around 93%. Some of the samples contained high and illegal formaldehyde levels ranging from 9% to 19% (w/w) and others presented suitable concentrations of the analyte. On the basis of the results, this work discusses the efficiency and practicality of this analytical method for forensic purposes.
Multivariate Classification of Original and Fake Perfumes by Ion Analysis and Ethanol Content
Authors: Gomes Clêrton L. , de Lima Ari Clecius A. , Loiola Adonay R. , da Silva Abel B. R. , Cândido Manuela C. L. , Nascimento Ronaldo F.
Published: February 2016

The increased marketing of fake perfumes has encouraged us to investigate how to identify such products by their chemical characteristics and multivariate analysis. The aim of this study was to present an alternative approach to distinguish original from fake perfumes by means of the investigation of sodium, potassium, chloride ions, and ethanol contents by chemometric tools. For this, 50 perfumes were used (25 original and 25 counterfeit) for the analysis of ions (ion chromatography) and ethanol (gas chromatography). The results demonstrated that the fake perfume had low levels of ethanol and high levels of chloride compared to the original product. The data were treated by chemometric tools such as principal component analysis and linear discriminant analysis. This study proved that the analysis of ethanol is an effective method of distinguishing original from the fake products, and it may potentially be used to assist legal authorities in such cases.
A Study of the Presence of Gunshot Residue in Pittsburgh Police Stations using SEM/EDS and LC‐MS/MS
Authors: Ali Leah , Brown Kyle , Castellano Holly , Wetzel Stephanie J.
Published: February 2016

Due to possible secondary transfer of gunshot residue (GSR) onto a suspect in police custody prior to sampling, a baseline must be created for the amount of GSR present. With an increase of “lead free” ammunition, testing for both gunpowder and primer GSR is relevant. Seventy samples were collected using carbon‐coated adhesive stubs from four Pittsburgh Police Stations and vehicles to investigate these locations as sources of secondary GSR contamination. These seventy samples were analyzed for primer GSR using scanning electron microscopy‐energy‐dispersive X‐ray spectrometry. One primer GSR particle was detected; no sample was classified as positive for primer GSR. These same samples were then analyzed for gunpowder GSR using liquid chromatography coupled to tandem mass spectrometry to test for akardite II, ethylcentralite, diphenylamine, N‐nitrosodiphenylamine, 2‐nitrodiphenylamine, and 4‐nitrodiphenylamine. Ethylcentralite was quantifiable in two test samples. These results suggest there is a negligible potential for secondary transfer of primer and gunpowder GSR.
Shadows on the landscape: an inquiry into the value of some Australian places
Authors: Sumner Ray
Published: February 2016

In 1922, Australian places connected with a solar eclipse were of world‐historical significance as they were associated with empirical confirmation of Einstein's general theory of relativity. They also formed a major part of Australian national consciousness, although they have since reverted to lost geographies. An exploration of Australian reception of eclipse science leads to questions of official heritage construction and stereotypical national identity. An argument is presented for the importance of intangible heritage at national, communal, and individual levels. At the complex intersection between memory and identity, place value is investigated within wider social‐political formations with emphasis on participation across perceived boundaries of social class, gender, and ethnicity, including the valuable role of Aboriginal peoples.
Cyanobacterial gardens: the liverwort Frullania asagrayana acts as a reservoir of lichen photobionts
Authors: Cornejo Carolina , Scheidegger Christoph
Published: February 2016

Cyanobacteria are important mediators of unrelated lichen species, which form epiphytic communities that share the same cyanobiont. No study to date, however, has considered the role of cyanobacteria as mediator between lichens and bryophytes. In the present study, DNA barcoding (16S rDNA, rbcLX) was used to identify filamentous cyanobacteria living in close association with members of an epiphytic liverwort‐lichen community on balsam fir in Newfoundland. This study is the first to confirm the presence of Rhizonema strains in boreal forests where they are associated with the liverwort Frullania asagrayana and several lichen species. The majority of cyanobacterial haplotypes can associate with the liverwort, however, some lichen species appear to be more selective for single or closely related haplotypes. Some Rhizonema strains were found exclusively in association with boreal lichens, while others seem to be globally distributed and involved in different lichen symbioses of unrelated fungal lineages and of varying ecological traits. Complex biological interactions in a cyanobacteria‐mediated guild are proposed here, which explains composition and dynamics in bryophyte and lichen‐dominated epiphytic communities.
Filamentous phage SW1 is active and influences the transcriptome of the host at high‐pressure and low‐temperature
Authors: Jian Huahua , Xiong Lei , Xu Guanpeng , Xiao Xiang
Published: February 2016

As the most abundant biological entities on the planet, viruses are involved in global biogeochemical cycles, and they have been shown to play an important role in the overall functioning of the deep‐sea ecosystem. Nevertheless, little is known about whether and how deep‐sea viruses affect the physiology of their bacterial hosts. Previously, the filamentous phage SW1 was identified in the bathypelagic bacterium Shewanella piezotolerans WP3, which was isolated from the upper sediment of West Pacific ocean. In this study, phage SW1 was shown to be active under in situ environmental conditions (20 MPa and 4°C) by transmission electron microscopy and reverse‐transcription quantitative polymerase chain reaction. Further comparative analysis showed that SW1 had a significant influence on the growth and transcriptome of its host. The transcription of genes responsible for basic cellular activities, including the transcriptional/translational apparatus, arginine synthesis, purine metabolism and the flagellar motor, were down‐regulated by the phage. Our results present the first characterization of a phage–host interaction under high‐pressure and low‐temperature conditions, which indicated that the phage adjusted the energy utilization strategy of the host for improved survival in deep‐sea environments.
Habitat partitioning of marine benthic denitrifier communities in response to oxygen availability
Authors: Wittorf Lea , Bonilla‐Rosso Germán , Jones Christopher M. , Bäckman Ola , Hulth Stefan , Hallin Sara
Published: February 2016

Denitrification is of global significance for the marine nitrogen budget and the main process for nitrogen loss in coastal sediments. This facultative anaerobic respiratory pathway is modular in nature and the final step, the reduction of nitrous oxide (N2O), is performed by microorganisms with a complete denitrification pathway as well as those only capable of N2O reduction. Fluctuating oxygen availability is a significant driver of denitrification in sediments, but the effects on the overall N2O‐reducing community that ultimately controls the emission of N2O from marine sediments is not well known. To investigate the effects of different oxygen regimes on N2O reducing communities, coastal marine surface sediment was incubated in microcosms under oxic, anoxic or oscillating oxygen conditions in the overlying water for 137 days. Quantification of the genetic potential for denitrification, anammox and respiratory ammonification indicated that denitrification supported nitrogen removal in these sediments. Furthermore, denitrifiers with a complete pathway were identified as the dominant community involved in N2O reduction, rather than organisms that are only N2O reducers. Specific lineages within each group were associated with different oxygen regimes suggesting that oxygen availability in the overlying water is associated with habitat partitioning of N2O reducers in coastal marine surface sediments.
Amphibious adaptations in a newly recognized amphibious fish: Terrestrial locomotion and the influences of body size and temperature
Authors: Magellan Kit
Published: February 2016

Amphibious animals are adapted for both aquatic and terrestrial habitats. The conflicting requirements for dual habitats are perhaps most pronounced in the air‐breathing fishes, which represent an intermediate stage between the totally aquatic habitat and terrestrial colonization. A key requirement for amphibious fishes is terrestrial locomotion. The different densities and compositions of air and water impose constraints for efficient terrestrial locomotion that differ from those required for aquatic locomotion. I investigated terrestrial locomotion in a small South African fish, Galaxias ‘nebula’, by exposing 60 individual fish to air in specially designed raceways and quantifying movement type and occurrence as a function of availability of water, fish size and environmental temperature. Nebula showed a sustained undulating form of terrestrial locomotion characteristic of amphibious fishes and also a transient ballistic locomotion (jumps) typical of fully aquatic species. Terrestrial movement was influenced by fish size, with medium‐sized fish undertaking more jumps towards water, and fewer jumps away from water, than their smaller or larger conspecifics. In contrast, axial undulation was mainly influenced by temperature. However, there was no consistent pattern in temperature effects presumably because temperature is just one of a suit of environmental factors that may affect terrestrial locomotion. Nebula's amphibious adaptations allow it to cope with the unpredictability inherent in its natural environment.
Real time cerebral perfusion monitoring in acute trauma patients: a preliminary study
Authors: Kessel Boris , Alfici Ricardo , Korin Alexander , Olsha Oded , Dudkiewicz Mickey , Oren Meir
Published: February 2016

Background

Management of traumatic brain injury is focused on preventing secondary damage. Early recognition of brain ischaemia may improve the final outcome of the trauma victim. The primary aim of this study was to examine the correlation between peripheral oxygen pulse oximetry and brain oxygen saturation measured by a near infrared oximetry device. A second aim was to evaluate the influence of different factors such as fluid and blood administration on brain tissue oxygenation.

Methods

This was a prospective pilot study. Mechanically ventilated trauma patients admitted to the trauma unit had cerebral‐somatic oxygen saturation monitoring. Oximeter readings (rSO2) were prospectively collected and compared with concurrent values for peripheral pulse oximetry (SO2). Data were recorded every 15 min and during interventions such as administration of a fluid bolus and blood administration. All interventions were based on accepted clinical parameters.

Results

Thirty‐three patients were enrolled. A total of 210 simultaneous measurements of rSO2 and pulse oximetry values were performed. There was correlation between these two parameters in only one third of patients. Twenty‐seven events of possible brain ischemia, defined as rSO2 values less than 50 or a decrease of more than 20% from the baseline, were observed. In 68 (77.2%) of these measurements there was no decrease of peripheral SO2. Significant increases in rSO2 were observed only during administration of fluid boluses.

Conclusions

A cerebral oxygenation monitoring device may recognize the possible events of brain ischaemia which are not reflected by pulse oximetry. Fluid administration was the only factor found to improve brain saturation.
Improving visual prognosis of the diabetic patients during the past 30 years based on the data of the Finnish Register of Visual Impairment
Authors: Laatikainen Leila , Ojamo Matti , Rudanko Sirkka‐Liisa , Summanen Paula , Keinänen‐Kiukaanniemi Sirkka , Tuomilehto Jaakko , Herrala Sauli , Uusitalo Hannu
Published: February 2016

Purpose

To evaluate changes in visual impairment (VI) due to diabetic retinopathy (DR) recorded in the Finnish Register of Visual Impairment (RVI) during the past 30 years.

Methods

Data from the visually impaired diabetic persons included in the RVI were analysed using three 10‐year cohorts (1982–90, 1991–2000, 2001–10). Information on the age at the time of the first VI registration, severity of VI determined according to the World Health Organisation (WHO) definition, and the age at death was collected. VI due to proliferative (PDR) and non‐proliferative (NPDR) DR were analysed separately.

Results

Data of 4080 patients whose primary cause for VI was DR were analysed. The median age at the time of notification of VI for the three cohorts was 39, 62 and 59 years in the PDR group and 71, 73 and 73 in the NPDR group, respectively. The proportion of blind persons was 42%, 22% and 15% in the PDR group and 10%, 9% and 4% in the NPDR group, respectively. The median age at death in the three cohorts was 54, 73 and 72 years in PDR group and 76, 79 and 80 years in the NPDR group, respectively. The standardized mortality ratio (SMR) compared with the general population was 8.3, 2.9 and 1.4 in persons with PDR and 3.4, 2.0 and 1.2 in those with NPDR, respectively.

Conclusions

A significant change in the profile of the VI in the PDR group has taken place in Finland. It was characterized by increased age at the time of VI notification, decreased severity of VI and higher age at death. Most evidently these improvements took place in the 1990s. The profile of VI in the NPDR group has changed only modestly. Compared with the general population, SMRs improved both in NPDR and PDR groups continuously.
Continuity and Change in the Field of Cognitive Development and in the Perspectives of One Cognitive Developmentalist
Authors: Siegler Robert S.
Published: February 2016

In this article, I examine changes in the field of cognitive development and in my own thinking over the past 40 years. The review focuses on three periods. In the first, Piaget's theory was dominant, and my research and that of many others was aimed at understanding the many fascinating changes in children's thinking that Piaget documented, and correcting inaccuracies in his theory. In the second period, which involved efforts to formulate alternatives to Piaget's approach, I generated overlapping waves theory, and attempted to specify through microgenetic methods and computer simulations how development can be produced by variability of strategy use, adaptive choices among strategies, and discovery of new strategies. In the third period, my thinking and research, and that of many others, has focused increasingly on the interface between cognitive development and education. I close by suggest that generating domain‐specific integrated theories of cognitive development may provide a way forward for the field.
Effects of testosterone replacement on metabolic and inflammatory markers in men with opioid‐induced androgen deficiency
Authors: Huang Grace , Travison Thomas , Maggio Marcello , Edwards Robert R. , Basaria Shehzad
Published: February 2016

Objective

Symptomatic androgen deficiency is common in patients taking opioid analgesics, and testosterone replacement in these men improves libido, quality of life and body composition. However, the effects of testosterone replacement on metabolic and inflammatory markers in this setting have not been evaluated. This is important as opiate use itself has been associated with metabolic abnormalities. The objective of this investigation was to determine the effects of testosterone administration on metabolic and inflammatory markers in adult men with opioid‐induced androgen deficiency.

Methods

Sixty‐four nondiabetic men aged 18 to 64 years using opioid analgesics for chronic noncancer pain with total testosterone levels <12 nmol/l were randomized to 14 weeks of transdermal testosterone gel or placebo gel daily. Total testosterone levels were measured by liquid chromatography mass spectrometry, and free testosterone was calculated using the law‐of‐mass‐action equation. Metabolic parameters, inflammatory markers and oral glucose tolerance test (OGTT) were evaluated at baseline and 14 weeks.

Results

Baseline characteristics were similar between the two groups. Testosterone concentrations increased from 7·7 ± 3·0 to 27 ± 19 nmol/l in the testosterone group, but did not meaningfully change in placebo group. Mean changes in metabolic and inflammatory markers during intervention did not differ significantly between groups and were not related to changes in on‐treatment serum testosterone concentrations. Glucose and insulin response to the 75 g OGTT also did not differ between groups.

Conclusion

In this 14‐week trial, testosterone administration in men with opioid‐induced androgen deficiency was not associated with worsening of metabolic and inflammatory markers.
Going Beyond Input Quantity: Wh‐Questions Matter for Toddlers' Language and Cognitive Development
Authors: Rowe Meredith L. , Leech Kathryn A. , Cabrera Natasha
Published: February 2016

There are clear associations between the overall quantity of input children are exposed to and their vocabulary acquisition. However, by uncovering specific features of the input that matter, we can better understand the mechanisms involved in vocabulary learning. We examine whether exposure to wh‐questions, a challenging quality of the communicative input, is associated with toddlers' vocabulary and later verbal reasoning skills in a sample of low‐income, African‐American fathers and their 24‐month‐old children (n = 41). Dyads were videotaped in free play sessions at home. Videotapes were transcribed and reliably coded for sheer quantity of fathers' input (number of utterances) as well as the number of wh‐questions fathers produce. Children's productive vocabulary was measured at 24 months using the McArthur Bates Communicative Development Inventory MCDI (completed by the mothers), and children's verbal reasoning skills were measured 1 year later using the Bayley Scales of Infant Development. Results indicate that the overall quantity of father talk did not relate to children's vocabulary or reasoning skills. However, fathers' use of wh‐questions (but not other questions) related to both vocabulary and reasoning outcomes. Children's responses to wh‐questions were more frequent and more syntactically complex, measured using the mean length of utterance (MLU), than their responses to other questions. Thus, posing wh‐questions to 2‐year‐olds is a challenging type of input, which elicits a verbal response from the child that likely helps build vocabulary and foster verbal reasoning abilities.