bluuebunny/crossref_metadata_2025 huggingface dataset:
Using opportunistic photo-identifications to detect a population decline of killer whales (Orcinus orca) in British and Irish waters
Authors: Beck Suzanne , Foote Andrew D. , Kötter Sandra , Harries Olivia , Mandleberg Laura , Stevick Peter T. , Whooley Pádraig , Durban John W.
Published: September 2013

An assemblage of killer whales that has been sighted in waters off the west coast of the British Isles and Ireland has previously been shown to be isolated from other North Atlantic killer whale communities based on association patterns. By applying a Bayesian formulation of the Jolly–Seber mark-recapture model to the photo-identification data compiled from opportunistic photographic encounters with this population of killer whales, we show that such sparse and opportunistically-collected data can still be valuable in estimating population dynamics of small, wide-ranging groups. Good quality photo-identification data was collected from 32 encounters over 19 years. Despite a cumulative total of 77 identifications from these encounters, just ten individuals were identified and the remaining 67 identifications were re-sights of these ten animals. There was no detected recruitment through births during the study and, as a result, the population appears to be in a slight decline. The demography of the population was highly skewed towards older individuals and had an unusually high ratio of adult males, and we suggest that demographic stochasticity due to a small population size may be further impacting the population growth rate. We recommend that this population be managed as a separate conservation unit from neighbouring killer whale populations.
The association between common mental disorders and violence: to what extent is it influenced by prior victimization, negative life events and low levels of social support?
Authors: ten Have M. , de Graaf R. , van Weeghel J. , van Dorsselaer S.
Published: September 2013

Background

Few studies have been published on the association between mental disorders and violence based on general population studies. Here we focus on different types of violence, adjusting for violent victimization and taking account of the limitations of previous population studies.

Method

Data were used from the first two waves of the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2), a nationally representative face-to-face survey of the general population aged 18–64 years (n = 6646). Violence was differentiated into physical and psychological violence against intimate partner(s), children or any person(s) in general. DSM-IV diagnoses were assessed with the Composite International Diagnostic Interview Version 3.0 (CIDI 3.0).

Results

Psychological violence occurs considerably more frequently than physical violence, but both showed almost identical associations with mental disorders. After adjustment for sociodemographic characteristics, most of the main categories of common mental disorders were associated with violence. The strongest associations were found for externalizing disorders (substance use, impulse-control, antisocial personality disorder). After additional adjustment for violent victimization, negative life events and social support, most diagnostic correlates lost their significance whereas substance use (in particular alcohol) disorders were still associated with most types of violence.

Conclusions

The increased risk of violent offending among people with common mental disorders, other than substance use disorders, can be attributed to factors other than their mental illness.
Combat exposure severity as a moderator of genetic and environmental liability to post-traumatic stress disorder
Authors: Wolf E. J. , Mitchell K. S. , Koenen K. C. , Miller M. W.
Published: September 2013

Background

Twin studies of veterans and adults suggest that approximately 30–46% of the variance in post-traumatic stress disorder (PTSD) is attributable to genetic factors. The remaining variance is attributable to the non-shared environment, which, by definition, includes combat exposure. This study used a gene by measured environment twin design to determine whether the effects of genetic and environmental factors that contribute to the etiology of PTSD are dependent on the level of combat exposure.

Method

The sample was drawn from the Vietnam Era Twin Registry (VETR) and included 620 male–male twin pairs who served in the US Military in South East Asia during the Vietnam War era. Analyses were based on data from a clinical diagnostic interview of lifetime PTSD symptoms and a self-report measure of combat exposure.

Results

Biometric modeling revealed that the effects of genetic and non-shared environment factors on PTSD varied as a function of level of combat exposure such that the association between these factors and PTSD was stronger at higher levels of combat exposure.

Conclusions

Combat exposure may act as a catalyst that augments the impact of hereditary and environmental contributions to PTSD. Individuals with the greatest exposure to combat trauma were at increased risk for PTSD as a function of both genetic and environmental factors. Additional work is needed to determine the biological and environmental mechanisms driving these associations.
Sub-femtosecond hard X-ray radiation generated by electron bunches ejected from water jet
Authors: Zhavoronkov N. , Andreev A. , Platonov K.
Published: September 2013

A new two-step approach for frequency conversion of laser radiation towards hard X-rays is developed and examined experimentally. Fast electrons are produced in a form of thin jets at the first stage, as an intense femtosecond laser pulses impinges on a micrometer water target. In the second stage the accelerated electrons hit a secondary metal target and generate characteristic K-shell radiation with a duration down to sub-femtosecond. It is shown that counter propagating laser radiation experiences very strong up-shift with up to 6 × 103 times of fundamental frequency by reflection from the electron jets.
Stable walking control of a 3D biped robot with foot rotation
Authors: Wang Ting , Chevallereau Christine , Tlalolini David
Published: September 2013

In order to obtain a more human-like walking and less energy consumption, ait foot rotation phaseis considered in the single support phase of a 3D biped robot, in which the stance heel lifts from the ground and the stance foot rotates about the toe. Since there is no actuation at the toe, a walking phase of the robot is composed of a fully actuated phase and an under-actuated phase. The objective of this paper is to present an asymptotically stable walking controller that integrates these two phases. To get around the under-actuation issue, a strict monotonic parameter of the robot is used to describe the reference trajectory instead of using the time parameter. The overall control law consists of a zero moment point (ZMP) controller, a swing ankle rotation controller and a partial joint angles controller. The ZMP controller guarantees that the ZMP follows the desired ZMP. The swing ankle rotation controller assures a flat-foot impact at the end of the swinging phase. Each of these controllers creates two constraints on joint accelerations. In order to determine all the desired joint accelerations from the control law, a partial joint angles controller is implemented. A word “partial” emphasizes the fact that not all the joint angles can be controlled. The outputs controlled by a partial joint angles controller are defined as a linear combination of all the joint angles. The most important question addressed in this paper is how this linear combination can be defined in order to ensure walking stability. The stability of the walking gait under closed-loop control is evaluated with the linearization of the restricted Poincaré map of the hybrid zero dynamics. Finally, simulation results validate the effectiveness of the control law even in presence of initial errors and modelling errors.
Termite mounds may not be foraging hotspots for mega-herbivores in a nutrient-rich matrix
Authors: Muvengwi Justice , Mbiba Monicah , Nyenda Tatenda
Published: September 2013

Our study investigated the influence of termitaria on vegetation utilization by elephants in Chewore North, Zimbabwe. Ten termite mounds and ten similar sized control plots were surveyed for soil nutrients, tree species diversity and plant biomass removal by elephants. Termite mounds had higher mean (± SE) concentrations of P, Ca, Mg and Na (0.15 ± 0.01, 48.8 ± 9.32, 5.78 ± 1.59 and 0.47 ± 0.12 meq per 100 g respectively) than control plots (0.05 ± 0.01, 3.33 ± 0.56, 1.53 ± 0.22 and 0.19 ± 0.02 meq per 100 g). However, Shannon Wiener index of tree diversity did not vary significantly between termite mounds (1.13 ± 0.280) and their control plots (0.827 ± 0.469). Contrary to most studies investigating patterns of vegetation utilization by large mammalian herbivores on termitaria, biomass removal was five times more on control plots than termite mounds. No difference in biomass removal was noted forColophospermum mopanewhich had enough replicates for statistical analysis both on termite mounds and control plots. Our study negates the hypothesis that nutrient-rich soil patches will act as feeding hotspots for large mammalian herbivores. We concluded that vegetation utilization by elephants may be tree species specific, particularly in nutrient-rich environments.
Unit-cell parameters for scapolite solid solutions and a discontinuity at Me75, ideally NaCa3[Al5Si7O24](CO3)
Authors: Antao Sytle M.
Published: September 2013

Twenty-seven scapolite samples from various localities and with compositions between Me6–93 were obtained using electron microprobe analysis (EMPA). Their unit-cell parameters were obtained using synchrotron high-resolution powder X-ray diffraction (HRPXRD) data and Rietveld structure refinements using space group P42/n. The EMPA data show the well-known discontinuity at Me75. In addition, the unit-cell parameters, especially c, show a discontinuity at Me75 (=five Al atoms per formula unit, apfu), ideally NaCa3[Al5Si7O24](CO3), where the scapolite solid solution is divided into two (Me% = [Ca/(Ca + Na + K)] × 100). A maximum c parameter value occurs at Me37.5 (=four Al apfu ideally), where complete Al–Si, Na–Ca, and Cl–CO3 order occurs. The unit-cell volume, V, varies smoothly with Me% and Al apfu across the series.
Epidemiological analysis of spatially misaligned data: a case of highly pathogenic avian influenza virus outbreak in Nigeria
Authors: ADEGBOYE O. A. , KOTZE D.
Published: September 2013

This research is focused on the epidemiological analysis of the transmission of the highly pathogenic avian influenza (HPAI) H5N1 virus outbreak in Nigeria. The data included 145 outbreaks together with the locations of the infected farms and the date of confirmation of infection. In order to investigate the environmental conditions that favoured the transmission and spread of the virus, weather stations were realigned with the locations of the infected farms. The spatial Kolmogorov–Smirnov test for complete spatial randomness rejects the null hypothesis of constant intensity (P < 0·0001). Preliminary exploratory analysis showed an increase in the incidence of H5N1 virus at farms located at high altitude. Results from the Poisson log-linear conditional intensity function identified temperature (−0·9601) and wind speed (0·6239) as the ecological factors that influence the intensity of transmission of the H5N1 virus. The model also includes distance from the first outbreak (−0·9175) with an Akaike's Information Criterion of −103·87. Our analysis using a point process model showed that geographical heterogeneity, seasonal effects, temperature, wind as well as proximity to the first outbreak are very important components of spread and transmission of HPAI H5N1.
AN EXPLANATION FOR THE DIVERSITY OF FINANCIAL STRUCTURE
Authors: Bose Niloy , Neumann Rebecca
Published: September 2013

This paper seeks to provide a theoretical explanation for the weak association between measures of financial structure—as defined by the mixture of bank-based and market-based financial systems in an economy—and economic development. Lenders fund risky investment projects of firms by drawing up loan contracts in the presence of an informational asymmetry. An optimal contract entails the issue of debt, equity, or a mix of the two. The equilibrium choice of contract and the financial structure depend on the state of the economy, which in turn depends on the contracting regime. Based on this analysis, the paper provides a theory that can explain the wide diversity of financial structure among middle-income countries.
Structure and Growth of Sialoliths: Computed Microtomography and Electron Microscopy Investigation of 30 Specimens
Authors: Nolasco Pedro , Anjos Ana J. , Marques João M. Aquino , Cabrita Fernando , da Costa Eduardo Carreiro , Maurício António , Pereira Manuel F.C. , de Matos António P. Alves , Carvalho Patricia A.
Published: September 2013

Theories have been put forward on the etiology of sialoliths; however, a comprehensive understanding of their growth mechanisms is lacking. In an attempt to fill this gap, the current study has evaluated the internal architecture and growth patterns of a set of 30 independent specimens of sialoliths characterized at different scales by computed microtomography and electron microscopy. Tomography reconstructions showed cores in most of the sialoliths. The cores were surrounded by concentric or irregular patterns with variable degrees of mineralization. Regardless of the patterns, at finer scales the sialoliths consisted of banded and globular structures. The distribution of precipitates in the banded structures is compatible with a Liesegang–Ostwald phenomenon. On the other hand, the globular structures appear to arise from surface tension effects and to develop self-similar features as a result of a viscous fingering process. Electron diffraction patterns demonstrated that Ca- and P-based electrolytes crystallize in a structure close to that of hydroxyapatite. The organic matter contained sulfur with apparent origin from sulfated components of secretory material. These results cast new light on the mechanisms involved in the formation of sialoliths.
New Associated Structures of the Anterior Flagella of Giardia duodenalis
Authors: Maia-Brigagão Claudia , Gadelha Ana Paula Rocha , de Souza Wanderley
Published: September 2013

Giardia duodenalis is a protozoan parasite that causes intestinal disorders. The trophozoites present four pairs of flagella. Here we further analyze the structural organization of the anterior flagella associated structures of G. duodenalis. High resolution scanning electron microscopy of detergent-extracted trophozoites revealed novel aspects of the interaction of the anterior flagella axonemes with the marginal plates. Images of the marginal plates showed that it was located in the anterior region of the parasite, above the crossing point of the anterior flagella axonemes toward the periphery of the cell. Two well distinguished structures were seen associated with the anterior flagella. The first one corresponds to the “dense rods”, located just below the axoneme. The second one is a system of filaments located in the upper portion of the flagellum, facing the marginal plates and connecting these two structures. The thickness of the filaments is around 18 nm and they are spaced at intervals of 4–32 nm (average 18 nm). The length of the filaments may vary from 33 to 240 nm. We suggest that this filamentous structure of Giardia may help the dynamics and behavior of the anterior flagella of trophozoites during protozoan motility and adhesion, providing favorable conditions for the establishment of parasitism.
Cryogenic Transmission Electron Microscopy: Aqueous Suspensions of Nanoscale Objects
Authors: Burrows Nathan D. , Penn R. Lee
Published: September 2013

Direct imaging of nanoscale objects suspended in liquid media can be accomplished using cryogenic transmission electron microscopy (cryo-TEM). Cryo-TEM has been used with particular success in microbiology and other biological fields. Samples are prepared by plunging a thin film of sample into an appropriate cryogen, which essentially produces a snapshot of the suspended objects in their liquid medium. With successful sample preparation, cryo-TEM images can facilitate elucidation of aggregation and self-assembly, as well as provide detailed information about cells and viruses. This work provides an explanation of sample preparation, detailed examples of the many artifacts found in cryo-TEM of aqueous samples, and other key considerations for successful cryo-TEM imaging.
Jurisprudential developments on the purpose of WTO suspension of obligations
Authors: TIJMES JAIME
Published: September 2013

This article examines World Trade Organization (WTO) jurisprudence on the question as to if the purpose of suspending concessions or other obligations is to induce compliance, to rebalance concessions, or both. WTO jurisprudence on this issue can be systematized into three steps. First, inducing compliance is the general purpose of suspension as complaining parties have the right to request the authorization to suspend concessions or other obligations as long as they meet the requirements spelled out in the WTO Dispute Settlement Understanding. The second step relates to the level of suspension. In general, WTO jurisprudence has accorded a higher hierarchy to the purpose of rebalancing concessions or other obligations, with some exceptions made regarding disputes on prohibited subsidies and diachronically variable suspension levels. As a third step, WTO jurisprudence has bestowed complaining Members freedom concerning the suspension's content, so as to induce the defending party to comply. Keeping these three steps in mind will hopefully make understanding WTO jurisprudence on suspension of concessions or other obligations easier.
Microsatellite marker analysis reveals the events of the introduction and spread of cultivated mulberry in the Indian subcontinent
Authors: Krishnan R. Ramesh , Naik V. Girish , Ramesh S. R. , Qadri S. M. H.
Published: September 2013

The secret art of silk culture along with mulberry seeds is presumed to have spread from China to other parts of the world including India through the famous Silk Road. In this study, we investigated a set of 36 important mulberry genotypes (designated as ‘breeders’ collection’) of historical importance that have been frequently used in Indian crop improvement programmes over the last five decades. This study is the first to employ a large number of microsatellite markers (140 screened; 70 used for profiling) to elucidate the diversity, structure and breeding history of mulberry. The cluster and STRUCTURE analysis corroborated with the known genetic relationships and origin. The groupings by STRUCTURE (k= 4) confirm parallel breeding efforts undertaken in the eastern, southern and northern regions of the country. The cultivar ‘Mysore Local’ shares a common parent with ‘Berhampore Local’, and this supports the historical records of its introduction from eastern India to the Kingdom of Mysore by the erstwhile ruler Tippu Sultan. The popular variety ‘Kanva-2’ shared a common male parent with the Japanese variety ‘Kousen’, supporting the contribution of exotic progenitors in Indian cultivars. The findings of this study will be useful in formulating new strategies for mulberry improvement and reveals the historical events of the introduction and spread of cultivated mulberry in the Indian subcontinent.
NetNotes
Authors: Phillips Thomas E.
Published: September 2013

Selected postings from the Microscopy Listserver from May 1, 2013 to June 30, 2013. Complete listings and subscription information can be obtained at http://www.microscopy.com. Postings may have been edited to conserve space or for clarity.
2013 Microscopy Today Innovation Awards
Authors: Lyman Charles
Published: September 2013

The editors congratulate the winners of the fourth annual Microscopy Today Innovation Awards competition. These awards were established to honor innovative microscopy-related products and methods that appeared in the previous year.
Calendar
Authors: Webster Paul
Published: September 2013

Following is a list of microscopy related meetings and courses. The editors would greatly appreciate input to this list via the electronic submission form under “events/other microscopy events” at the MSA webpage: www.microscopy.org. We will gladly add hypertext links to the notice on the web and insert a listing of the meeting in the next issue.
Context of Treatment and Therapeutic Alliance: Critical Factors in Court-Mandated Batterer Intervention Programs
Authors: Boira Santiago , del Castillo María F. , Carbajosa Pablo , Marcuello Chaime
Published: September 2013

This paper deals with the influence of the therapeutic context in batterer intervention programs. We conducted 2 complementary studies: a descriptive analysis (Study 1) and a qualitative study (Study 2) analyzing the aspects that may help to improve the operation and effectiveness of treatment in a group of men (N = 27) who participated in a program for convicted perpetrators of intimate partner violence. The results show a statistically significant relationship between the therapeutic alliance and the assessment of the usefulness of the program attended by offenders (r = .69, p < .01), and between the therapeutic alliance and the assessment of the usefulness of the program content (r = .43, p < .05). Furthermore, the results of the qualitative analysis show that aspects of the therapeutic context may play an important role for the adhesion of offenders to treatment, increasing their motivation and improving results. It is proposed that future research should provide more in-depth analysis of the elements related to the context of the intervention and therapists’ skills as facilitators of change.
Human DNA helicase HELQ participates in DNA interstrand crosslink tolerance with ATR and RAD51 paralogs
Authors: Takata Kei-ichi , Reh Shelley , Tomida Junya , Person Maria D. , Wood Richard D.
Published: September 2013

Mammalian HELQ is a 3′–5′ DNA helicase with strand displacement activity. Here we show that HELQ participates in a pathway of resistance to DNA interstrand crosslinks (ICLs). Genetic disruption ofHELQin human cells enhances cellular sensitivity and chromosome radial formation by the ICL-inducing agent mitomycin C (MMC). A significant fraction of MMC sensitivity is independent of the Fanconi anaemia pathway. Sister chromatid exchange frequency and sensitivity to UV radiation or topoisomerase inhibitors is unaltered. Proteomic analysis reveals that HELQ is associated with the RAD51 paralogs RAD51B/C/D and XRCC2, and with the DNA damage-responsive kinase ATR. After treatment with MMC, reduced phosphorylation of the ATR substrate CHK1 occurs inHELQ-knockout cells, and accumulation of G2/M cells is reduced. The results indicate that HELQ operates in an arm of DNA repair and signalling in response to ICL. Further, the association with RAD51 paralogs suggests HELQ as a candidate ovarian cancer gene.
Using Network Biology to Bridge Pharmacokinetics and Pharmacodynamics in Oncology
Authors: Kirouac DC , Onsum MD
Published: September 2013

If mathematical modeling is to be used effectively in cancer drug development, future models must take into account both the mechanistic details of cellular signal transduction networks and the pharmacokinetics (PK) of drugs used to inhibit their oncogenic activity. In this perspective, we present an approach to building multiscale models that capture systems‐level architectural features of oncogenic signaling networks, and describe how these models can be used to design combination therapies and identify predictive biomarkers in silico.

CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e71; doi:10.1038/psp.2013.38; published online 4 September 2013
Rapid optimisation of omnidirectional antennas using adaptively adjusted design specifications and kriging surrogates
Authors: Koziel Slawomir , Ogurtsov Stanislav
Published: September 2013

A methodology for rapid design optimisation of omnidirectional antennas is presented. In order to reduce the computational cost of the geometry parameter adjustment process the authors exploit coarse discretisation electromagnetic (EM) simulations of the antenna structure under consideration as its low‐fidelity model. A fast response surface approximation (RSA) model of the sampled EM data is created using kriging interpolation. The RSA model is subsequently used in the surrogate‐based design process with the adaptively adjusted design specification (AADS) technique utilised as the optimisation engine. AADS allows us to account for the discrepancy between the surrogate and the high‐fidelity EM antenna model. The optimised designs can be obtained at a low computational cost corresponding to a few evaluations of the high‐fidelity antenna model as demonstrated through examples. Comparison with the benchmark technique indicates that using the RSA surrogates results in substantial reduction of the overall optimisation cost.
Partial discharge behaviours within a void‐dielectric system under square waveform applied voltage stress
Authors: Illias Hazlee Azil , Tunio Mohsin Ali , Abu Bakar Ab Halim , Mokhlis Hazlie , Chen George
Published: September 2013

There are many factors, which influence the behaviours of partial discharge (PD) within a void located in a solid dielectric material. One of the important factors is the waveform of the applied voltage on the electrode of a system, such as its amplitude and frequency. In this study, a two‐dimensional axial‐symmetric model of a cylindrical void in polyethylene layers has been developed using finite element analysis software. The model was used to simulate PD activity in the void under square waveform applied voltage under different amplitudes of the voltage. The model has considered the effect of charge propagation along the void surface during a PD occurrence. The obtained simulation results were compared with the measurement results reported from previous literature to validate the PD model that has been developed in this work. It was found that the simulation and measurement results are within reasonable agreement with only slight disagreement. From the comparison, critical parameters from the model that affect PD behaviours under square waveform applied voltage were found to be the electron generation rate and the inception, extinction and critical charge propagation fields. These findings may increase an understanding of PD behaviours within a void in a dielectric material under square waveform applied voltage, which is important for insulation diagnosis.
Reduction of differential‐mode to common‐mode conversion by means of analytic description in common‐mode chokes used for an automotive communication bus system
Authors: Spägele Matthias , Buntz Stefan , Leier Helmut , Reiter Leopold , Lindenmeier Stefan
Published: September 2013

The following study describes the attempt to reduce differential‐mode to common‐mode conversion of data‐line common‐mode chokes (CMCs) which are used in unshielded‐twisted‐pair automotive communication bus systems. Conversion of a choke leads directly to emissions of the data line. Furthermore, the emission within the information signal's frequency range varies depending on the signal conversion. For high speed bus systems like for example 100 Mbit/s Ethernet, this leads to a significant emission in case of state‐of‐the‐art CMCs used nowadays. The study is based on measurement results, simulations and an analytic description of different CMCs. In the analytic description all important parameters of a choke contributing to the mode conversion are shown. These parameters are the length of connection lines (connection from the windings on the coil to the package) and the length difference between the connection lines, as well as the characteristic impedance of connection lines and the characteristic impedance difference between the connection lines. The study indicates that the conversion factor and the emission level decrease by 10 dB when the length difference between the connection lines reduces from 4.8 to 0.2 mm. The overall result shows that the reduction of conversion factor is 25 dB when all parameters introducing in this study are optimised. The theory described in this study can point out the mutual influence of parameters and the weighting or prioritisation of parameters. This means that it is possible to design CMCs with small conversion and hereby reduce the emissions of an unshielded‐twisted‐pair automotive communication bus system.
Photocatalytic digestion of total phosphorus utilising nanotitanium dioxide photocatalyst
Authors: Dong Tian , Tong Jianhua , Bian Chao , Sun Jizhou , Xia Shanhong
Published: September 2013

Thermal‐assisted ultraviolet (UV) and H2O2‐assisted UV photocatalytic oxidation methods utilizing nano‐TiO2 photocatalyst are presented for the digestion of total phosphorus (TP) in water. The photocatalytic experiments for TP digestion were conducted using a 365 nm wavelength UV light, and TiO2 nanoparticles immobilized on a silicon wafer as the photocatalyst. The effects of H2O2 and temperature on the UV photocatalytic oxidation process are explained. The pseudo‐first‐order rate constants k of two phosphorus compounds for the UV digestion processes were obtained according to the pseudo‐first‐order equation. Both H2O2 and heating could improve the efficiency of the UV photocatalytic oxidation method. But by comparison, the enhancement of heating on the UV photocatalysis process is more distinctly than H2O2. In addition, the thermal‐assisted UV digestion process will not lead to secondary pollution since no oxidant is needed in this digestion process, which makes it more compatible with electrochemical detection of TP. The thermal‐assisted UV digestion method was employed for the digestion of real water samples. Compared with the conventional thermal digestion method for TP detection, this thermal‐assisted UV digestion process decreased the digestion temperature from 120°C to 60°C within the same time, which enable the digestion process work at normal pressure.
Core–shelled Zn/ZnO microspheres synthesised by ultrasonic irradiation for photocatalytic applications
Authors: Ma Qing‐lan , Xiong Rui , Zhai Bao‐gai , Huang Yuan Ming
Published: September 2013

Core–shelled Zn/ZnO microspheres were prepared by ultrasonic irradiation to investigate their photocatalytic activity for degrading methyl orange in waste water. The microstructural and optical properties of the core–shelled Zn/ZnO microspheres were investigated by means of a scanning electron microscope, a transmission electron microscope, an X‐ray diffractometer and a photoluminescence spectrometer. The results indicated that the metallic Zn core was about 6 μm in diameter whereas the ZnO shell was about 200 nm in thickness. Owing to the metal–semiconductor junction formed at the Zn/ZnO interface, the core‐shelled Zn/ZnO microspheres exhibited higher photocatalytic activity for degrading methyl orange in water when compared with that of ZnO nanoparticles. It suggests that the core–shelled Zn/ZnO microspheres are a promising photocatalyst for the degradation of organic pollutants in water.
Root growth and N dynamics in response to multi-year experimental warming, summer drought and elevated CO2 in a mixed heathland-grass ecosystem
Authors: Arndal M. F. , Schmidt I. K. , Kongstad J. , Beier C. , Michelsen A.
Published: September 2013

Ecosystems exposed to elevated CO2 are often found to sequester more atmospheric carbon due to increased plant growth. We exposed a Danish heath ecosystem to elevated CO2, elevated temperature and extended summer drought alone and in all combinations in order to study whether the expected increased growth would be matched by an increase in root nutrient uptake of NH4+-N and NO3– -N. Root growth was significantly increased by elevated CO2. The roots, however, did not fully compensate for the higher growth with a similar increase in nitrogen uptake per unit of root mass. Hence the nitrogen concentration in roots was decreased in elevated CO2, whereas the biomass N pool was unchanged or even increased. The higher net root production in elevated CO2 might be a strategy for the plants to cope with increased nutrient demand leading to a long-term increase in N uptake on a whole-plant basis. Drought reduced grass root biomass and N uptake, especially when combined with warming, but CO2 was the most pronounced main factor effect. Several significant interactions of the treatments were found, which indicates that the responses were nonadditive and that changes to multiple environmental changes cannot be predicted from single-factor responses alone.
Pregnant women’s use of information and communications technologies to access pregnancy-related health information in South Australia
Authors: Rodger D. , Skuse A. , Wilmore M. , Humphreys S. , Dalton J. , Flabouris M. , Clifton V. L.
Published: September 2013

This paper examines how pregnant women living in South Australia use information and communication technologies (ICTs), principally Internet and mobile phones, to access pregnancy-related information. It draws on 35 semistructured interviews conducted as part of the ‘Health-e Baby’ project, a qualitative study designed to assess the information needs and ICT preferences of pregnant women cared for at a South Australian metropolitan teaching hospital. Our research shows that although ICTs offer exciting possibilities for health promotion and the potential for new forms of communication, networking and connection, we cannot assume the effectiveness of communicating through such channels, despite near universal levels of ICT access. In turn, this highlights that if e-mediated health promotion is to be effective, health promoters and practitioners need to better understand ICT access, usage and content preferences of their clients.
Processing of hierarchical syntactic structure in music
Authors: Koelsch Stefan , Rohrmeier Martin , Torrecuso Renzo , Jentschke Sebastian
Published: September 2013

Hierarchical structure with nested nonlocal dependencies is a key feature of human language and can be identified theoretically in most pieces of tonal music. However, previous studies have argued against the perception of such structures in music. Here, we show processing of nonlocal dependencies in music. We presented chorales by J. S. Bach and modified versions in which the hierarchical structure was rendered irregular whereas the local structure was kept intact. Brain electric responses differed between regular and irregular hierarchical structures, in both musicians and nonmusicians. This finding indicates that, when listening to music, humans apply cognitive processes that are capable of dealing with long-distance dependencies resulting from hierarchically organized syntactic structures. Our results reveal that a brain mechanism fundamental for syntactic processing is engaged during the perception of music, indicating that processing of hierarchical structure with nested nonlocal dependencies is not just a key component of human language, but a multidomain capacity of human cognition.
Zinc finger protein Loz1 is required for zinc-responsive regulation of gene expression in fission yeast
Authors: Corkins Mark E. , May Margot , Ehrensberger Kate M. , Hu Ya-Mei , Liu Yi-Hsuan , Bloor Sean D. , Jenkins Blair , Runge Kurt W. , Bird Amanda J.
Published: September 2013

Significance

Zinc is an essential nutrient that is a cofactor in a wide range of enzymes and regulatory proteins. However, in excess, zinc is toxic to growth. As a consequence, all cells required mechanisms to maintain an optimal level of zinc. Despite a wealth of knowledge of proteins that use a structural or catalytic zinc cofactor, relatively little is know about the factors that sense and regulate intracellular zinc levels in eukaryotes. This report demonstrates that Loz1, a transcriptional repressor that contains a double C
2
H
2
-type zinc finger domain, plays a central role in zinc homeostasis in
Schizosaccharomyces pombe
. These studies provide important insight into the types of proteins and possible domains that can be used to sense zinc ions.
The Hawthorne effect and energy awareness
Authors: Schwartz Daniel , Fischhoff Baruch , Krishnamurti Tamar , Sowell Fallaw
Published: September 2013

The feeling of being observed or merely participating in an experiment can affect individuals’ behavior. Referred to as the Hawthorne effect, this inconsistently observed phenomenon can both provide insight into individuals' behavior and confound the interpretation of experimental manipulations. Here, we pursue both topics in examining how the Hawthorne effect emerges in a large field experiment focused on residential consumers’ electricity use. These consumers received five postcards notifying, and then reminding, them of their participation in a study of household electricity use. We found evidence for a Hawthorne (study participation) effect, seen in a reduction of their electricity use—even though they received no information, instruction, or incentives to change. Responses to a follow-up survey suggested that the effect reflected heightened awareness of energy consumption. Consistent with that interpretation, the treatment effect vanished when the intervention ended.
How minute sooglossid frogs hear without a middle ear
Authors: Boistel Renaud , Aubin Thierry , Cloetens Peter , Peyrin Françoise , Scotti Thierry , Herzog Philippe , Gerlach Justin , Pollet Nicolas , Aubry Jean-François
Published: September 2013

Significance

Gardiner's Seychelle frog, one of the smallest terrestrial tetrapods, resolves an apparent paradox as these seemingly deaf frogs communicate effectively without a middle ear. Acoustic playback experiments conducted using conspecific calls in the natural habitat of the frogs provoked vocalizations of several males, suggesting that these frogs are indeed capable of hearing. This species thus uses extra-tympanic pathways for sound propagation to the inner ear. Our models show how bone conduction is enhanced by the resonating role of the mouth and may help these frogs hear.
Microbial diversity in The Cedars, an ultrabasic, ultrareducing, and low salinity serpentinizing ecosystem
Authors: Suzuki Shino , Ishii Shun’ichi , Wu Angela , Cheung Andrea , Tenney Aaron , Wanger Greg , Kuenen J. Gijs , Nealson Kenneth H.
Published: September 2013

Significance

The Cedars, in coastal northern California, is an active serpentinization site. The spring waters emerging from this system feature very high pH (≈11.5), low redox potential (≈−550 mV), and low ionic concentrations, making it an exceptionally challenging environment for life. The microbial communities are different in different springs, strongly correlated with the source of the serpentinizing groundwater feeding the springs (shallow or deep). The shallow groundwater community was similar to those described in other terrestrial serpentinizing sites, while the deep community was distinctly different from any other previously described terrestrial serpentinizing community. These communities have the potential to yield important insights into survival mechanisms in these challenging, early-earth analog environments.
Opposing selection and environmental variation modify optimal timing of breeding
Authors: Tarwater Corey E. , Beissinger Steven R.
Published: September 2013

Studies of evolution in wild populations often find that the heritable phenotypic traits of individuals producing the most offspring do not increase proportionally in the population. This paradox may arise when phenotypic traits influence both fecundity and viability and when there is a tradeoff between these fitness components, leading to opposing selection. Such tradeoffs are the foundation of life history theory, but they are rarely investigated in selection studies. Timing of breeding is a classic example of a heritable trait under directional selection that does not result in an evolutionary response. Using a 22-y study of a tropical parrot, we show that opposing viability and fecundity selection on the timing of breeding is common and affects optimal breeding date, defined by maximization of fitness. After accounting for sampling error, the directions of viability (positive) and fecundity (negative) selection were consistent, but the magnitude of selection fluctuated among years. Environmental conditions (rainfall and breeding density) primarily and breeding experience secondarily modified selection, shifting optimal timing among individuals and years. In contrast to other studies, viability selection was as strong as fecundity selection, late-born juveniles had greater survival than early-born juveniles, and breeding later in the year increased fitness under opposing selection. Our findings provide support for life history tradeoffs influencing selection on phenotypic traits, highlight the need to unify selection and life history theory, and illustrate the importance of monitoring survival as well as reproduction for understanding phenological responses to climate change.
Synthesis and dissolution of hemicatenanes by type IA DNA topoisomerases
Authors: Lee Shun-Hsiao , Siaw Grace Ee-Lu , Willcox Smaranda , Griffith Jack D. , Hsieh Tao-Shih
Published: September 2013

Significance

A hemicatenane conjoins two DNA duplexes through a single-strand interlock. It has been proposed that hemicatenanes are important intermediates for replication, repair, and recombination. However, the biochemical analysis of hemicatenanes is hampered by the relative inaccessibility of such structures. We report here that a DNA topoisomerase III (Top3) from a hyperthermophilic archaeum can carry out synthesis and dissolution of hemicatenanes. We also show that a complex of human Top3α, Bloom helicase (Blm), and RecQ-mediated genome instability protein 1 and 2 has a biochemical function of reversing this hemicatenation. Our results demonstrate that type IA topoisomerases can regulate the formation of hemicatenane structures.
Interrogating translational efficiency and lineage-specific transcriptomes using ribosome affinity purification
Authors: Zhou Pingzhu , Zhang Yijing , Ma Qing , Gu Fei , Day Daniel S. , He Aibin , Zhou Bin , Li Jing , Stevens Sean M. , Romo Daniel , Pu William T.
Published: September 2013

Significance

We developed reagents and approaches to pull down ribosome-associated RNAs from Cre-labeled cells. We show that this strategy is useful to probe cell type-specific gene expression and the extent of transcript binding to ribosomes.
From extortion to generosity, evolution in the Iterated Prisoner’s Dilemma
Authors: Stewart Alexander J. , Plotkin Joshua B.
Published: September 2013

Significance

Cooperative behavior seems at odds with the Darwinian principle of survival of the fittest, yet cooperation is abundant in nature. Scientists have used the Prisoner Dilemma game, in which players must choose to cooperate or defect, to study the emergence and stability of cooperation. Recent work has uncovered a remarkable class of extortion strategies that provide one player a disproportionate payoff when facing an unwitting opponent. Extortion strategies perform very well in head-to-head competitions, but they fare poorly in large, evolving populations. Rather we identify a closely related set of generous strategies, which cooperate with others and forgive defection, that replace extortionists and dominate in large populations. Our results help to explain the evolution of cooperation.
Drift and conservation of differential exon usage across tissues in primate species
Authors: Reyes Alejandro , Anders Simon , Weatheritt Robert J. , Gibson Toby J. , Steinmetz Lars M. , Huber Wolfgang
Published: September 2013

Significance

In higher organisms, most genes consist of several disconnected regions (exons), which are combined in various ways to produce several different gene transcripts from the same gene. Such alternative exon usage is thought to contribute to the ability of organisms to generate different cell types and tissues from a single genome. However, recent evidence has also suggested that much alternative exon usage might be noise with no particular function. We reconcile these two views by comparing how exons are used in different tissues and for which exons these usage patterns across tissues change or stay similar (are “conserved”) in several primate species. The latter case is an indication that the pattern is of functional importance, and our analysis quantifies how widespread such cases are.
Pathogenic role of diabetes-induced PPAR-α down-regulation in microvascular dysfunction
Authors: Hu Yang , Chen Ying , Ding Lexi , He Xuemin , Takahashi Yusuke , Gao Yang , Shen Wei , Cheng Rui , Chen Qian , Qi Xiaoping , Boulton Michael E. , Ma Jian-xing
Published: September 2013

Significance

This study investigated the expression and function of peroxisome proliferator-activated receptor alpha (PPARα) in the retina and its role in diabetic retinopathy. In both type 1 and type 2 diabetes models, expression of PPARα was significantly down-regulated in the retina. PPARα knockout exacerbated diabetes-induced retinal vascular leakage and retinal inflammation, while over-expression of PPARα in the retina of diabetic rats significantly alleviated diabetic retinopathy. This study reveals that PPARα has an anti-inflammatory function in the retina. These findings also suggest that diabetes-induced down-regulation of PPARα plays an important role in diabetic retinopathy and represents a novel therapeutic target for diabetic retinopathy.
Physiological, anatomical, and behavioral changes after acoustic trauma in
Drosophila melanogaster
Authors: Christie Kevin W. , Sivan-Loukianova Elena , Smith Wesley C. , Aldrich Benjamin T. , Schon Michael A. , Roy Madhuparna , Lear Bridget C. , Eberl Daniel F.
Published: September 2013

Significance

Noise-induced hearing loss (NIHL) is an important health issue, yet its mechanisms and potential treatments remain unclear. We present the first study of NIHL in the fruit fly
Drosophila
, which has many advantages as an NIHL model. We examined auditory function and structure after exposing flies to acoustic trauma. Trauma impairs auditory system function and changes neural mitochondria size, suggesting metabolic stress. In mutant flies with a reduced ability to cope with such stresses, the responses to trauma were more severe and recovery delayed or impaired.
Unraveling the chromophoric disorder of poly(3-hexylthiophene)
Authors: Thiessen Alexander , Vogelsang Jan , Adachi Takuji , Steiner Florian , Vanden Bout David , Lupton John M.
Published: September 2013

Significance

Ideal photovoltaic cells would be black, absorbing all of the Sun’s radiation, whereas Nature’s machinery for solar energy harvesting—photosynthesis—looks green. Organic semiconductor devices, based on molecular building blocks, lie conceptionally between the extremes of inorganic and photosynthetic light harvesting. How can organic solar cells appear almost black if they are based on molecular units? Using single-molecule spectroscopy, we identify the fundamental electronic building blocks of organic solar cells and reveal that discrete molecule-like transitions scatter over the entire visible spectrum. The fundamental molecular unit is narrowband, but disorder induces a continuum reminiscent of that characterizing highly ordered inorganic crystals.
Evidence of recovery of
Juniperus virginiana
trees from sulfur pollution after the Clean Air Act
Authors: Thomas Richard B. , Spal Scott E. , Smith Kenneth R. , Nippert Jesse B.
Published: September 2013

Significance

This study shows that red cedar trees growing in the Central Appalachian Mountains of West Virginia are recovering from decades of acidic pollution. Our study shows the efficacy of the Clean Air Act in a region where acidic pollution levels were some of the highest in the United States before the Clean Air Act. We demonstrate that a large portion of the increase in water use efficiency of trees that is often attributed to increasing atmospheric CO
2
over the last century may be caused by acid deposition. This study has important implications for carbon cycling in forests, showing an interaction between decreasing SO
2
emissions and increasing CO
2
that is not currently accounted for in biosphere–atmosphere models of climate change.