bluuebunny/crossref_metadata_2025 huggingface dataset:
The relationship between economic growth and biomass energy consumption in some European countries
Authors: Bildirici Melike E. , Özaksoy Fulya
Published: April 2013

In this paper, the causality analysis between biomass energy consumption and economic growth was investigated in the selected 10 countries by using Autoregressive Distributed Lag bounds testing approach and vector error-correction models. Annual data cover the period from 1960 to 2010. The short run, long run, and strong causality results suggest that there is unidirectional causality from Y to biomass energy consumption for Austria and Turkey, and there is unidirectional causality from biomass energy consumption to Y for Hungary and Poland. For Spain, Sweden, and France, it was found as bidirectional causality. According to strong and long run causalities, bidirectional causality was found for all the countries.
“Silicon millefeuille”: From a silicon wafer to multiple thin crystalline films in a single step
Authors: Hernández David , Trifonov Trifon , Garín Moisés , Alcubilla Ramon
Published: April 2013

During the last years, many techniques have been developed to obtain thin crystalline films from commercial silicon ingots. Large market applications are foreseen in the photovoltaic field, where important cost reductions are predicted, and also in advanced microelectronics technologies as three-dimensional integration, system on foil, or silicon interposers [Dross et al., Prog. Photovoltaics 20, 770-784 (2012); R. Brendel, Thin Film Crystalline Silicon Solar Cells (Wiley-VCH, Weinheim, Germany 2003); J. N. Burghartz, Ultra-Thin Chip Technology and Applications (Springer Science + Business Media, NY, USA, 2010)]. Existing methods produce “one at a time” silicon layers, once one thin film is obtained, the complete process is repeated to obtain the next layer. Here, we describe a technology that, from a single crystalline silicon wafer, produces a large number of crystalline films with controlled thickness in a single technological step.
Band alignment tuning of InAs quantum dots with a thin AlGaAsSb capping layer
Authors: Liao Yu-An , Hsu Wei-Ting , Huang Shih-Han , Chiu Pei-Chin , Chyi Jen-Inn , Chang Wen-Hao
Published: April 2013

We investigate the optical properties of InAs quantum dots (QDs) capped with a thin AlxGa1−xAsSb layer. As evidenced from power-dependent and time-resolved photoluminescence (PL) measurements, the GaAsSb-capped QDs with type-II band alignment can be changed to type-I by adding Al into the GaAsSb capping layer. The evolution of band alignment with the Al content in the AlGaAsSb capping layer has also been confirmed by theoretical calculations based on 8-band k⋅p model. The PL thermal stability and the room temperature PL efficiency are also improved by AlGaAsSb capping. We demonstrate that using the quaternary AlGaAsSb can take the advantages of GaAsSb capping layer on the InAs QDs while retaining a type-I band alignment for applications in long-wavelength light emitters.
Spontaneous formation of InGaN nanowall network directly on Si
Authors: Soto Rodriguez P. E. D. , Kumar Praveen , Gómez V. J. , Alvi N. H. , Mánuel J. M. , Morales F. M. , Jiménez J. J. , García R. , Calleja E. , Nötzel R.
Published: April 2013

We present the study on epitaxial growth of an InGaN nanowall network directly on Si by plasma-assisted molecular beam epitaxy. Scanning electron microscopy, high-resolution X-ray diffraction, and transmission electron microscopy together with energy-dispersive X-ray analysis infer the crystalline nature of the InGaN nanowall network, oriented along the C-axis, with In composition ranging from pure GaN to 40%. Room temperature photoluminescence is observed, indicating good optical quality. The nanowall network is highly in-plane electrically conductive.
Impact of Joule heating on the microstructure of nanoscale TiO2 resistive switching devices
Authors: Meng Lu Yi , Noman Mohammad , Picard Yoosuf N. , Bain James A. , Salvador Paul A. , Skowronski Marek
Published: April 2013

The microstructure of TiO2 functional layers in nanoscale resistive switching devices was analyzed using Scanning Electron and Transmission Electron Microscopies (SEM and TEM). The TiO2 layers in as-fabricated devices were amorphous with very weak lattice fringes in High Resolution TEM. After electroformation with low power dissipation (PDIS < 0.4 mW), the microstructural changes in the TiO2 layer were limited to an area approximately 75∼100 nm in radius indicating that the current path and Joule heating were localized. Since the reset power (≈2.4 mW) was greater than the electroformation power, switching cycles resulted in an increased area of the TiO2 affected zone and more morphological changes to the Pt electrodes and functional layers. Electroformation under large power dissipation (15 mW) led to massive redistribution of Pt, including shorting of electrodes through the oxide layer. Modeling temperature distribution in the devices found maximum temperature to be strongly dependent on the power dissipation. Computational estimates of the temperature exceed 323 °C at electroformation (0.4 mW), 819 °C at reset (2.4 mW), and the melting point of Pt electrode at large power (15 mW) dissipation. The microstructural changes appear to be caused by Joule heating during device operation.
The time evolution of turbulent parameters in reversed-field pinch plasmas
Authors: Titus J. B. , Alexander Brandon , Johnson J. A.
Published: April 2013

Turbulence is abundant in fully ionized fusion plasmas, with unique turbulent characteristics in different phases of the discharge. Using Fourier and chaos-based techniques, a set of parameters have been developed to profile the time evolution of turbulence in high temperature, fusion plasmas, specifically in self-organized, reversed-field pinch plasma in the Madison Symmetric Torus. With constant density and plasma current, the turbulence profile is measured during ramp-up, magnetic reconnection, and increased confinement phases. During magnetic reconnection, a scan of plasma current is performed with a constant density. Analysis revealed that the energy associated with turbulence (turbulent energy) is found to increase when changes in magnetic energy occur and is correlated to edge ion temperatures. As the turbulent energy increases with increasing current, the rate at which this energy flow between scales (spectral index) and anti-persistence of the fluctuations increases (Hurst exponent). These turbulent parameters are then compared to the ramp-up phase and increased confinement regime.
Polar-drive implosions on OMEGA and the National Ignition Facility
Authors: Radha P. B. , Marshall F. J. , Marozas J. A. , Shvydky A. , Gabalski I. , Boehly T. R. , Collins T. J. B. , Craxton R. S. , Edgell D. H. , Epstein R. , Frenje J. A. , Froula D. H. , Goncharov V. N. , Hohenberger M. , McCrory R. L. , McKenty P. W. , Meyerhofer D. D. , Petrasso R. D. , Sangster T. C. , Skupsky S.
Published: April 2013

Polar-drive (PD) experiments on the OMEGA [Boehly et al., Opt. Commun. 133, 495 (1997)] laser are described. Continuous pulse shapes, where a low-power foot is followed by a rise to the main pulse, and triple-picket pulse shapes, where three pickets precede the main pulse, are used to irradiate warm plastic shell capsules. Both of these pulse shapes set the target on a low, ignition-relevant adiabat of ∼3.5. The areal density is modeled very well in these implosions indicating that shock timing is well modeled in PD geometry. It is shown that the symmetry can be predictably varied by changing the beam pointings. Symmetry is also well reproduced across the two pulse shapes. Limitations of OMEGA experiments are discussed. Preliminary designs for PD implosion experiments on the NIF, with the goal of addressing ignition-relevant issues for PD, including symmetry are presented.
The mitigating effect of magnetic fields on Rayleigh-Taylor unstable inertial confinement fusion plasmas
Authors: Srinivasan Bhuvana , Tang Xian-Zhu
Published: April 2013

Rayleigh-Taylor (RT) instabilities at interfaces of disparate mass densities have long been known to generate magnetic fields during inertial confinement fusion implosions. An externally applied magnetic field can also be efficiently amplified by RT instabilities. The focus here is on magnetic field generation and amplification at the gas-ice interface which is RT unstable during the deceleration phase of the implosion. RT instabilities lead to undesirable mix of hot and cold plasmas which enhances thermal energy loss and tends to produce a more massive warm-spot instead of a hot-spot. Two mechanisms are shown here to mitigate the thermal energy loss from the hot-spot. The first mechanism is the reduction of electron thermal conductivity with interface-aligned magnetic fields. This can occur through self-generated magnetic fields via the Biermann battery effect as well as through externally applied magnetic fields that undergo an exponential growth via the stretch-and-fold magnetohydrodynamic dynamo. Self-generated magnetic fields during RT evolution can result in a factor of 2−10 decrease in the electron thermal conductivity at the gas-ice interface, while externally applied magnetic fields that are compressed to 6–1000 T at the onset of deceleration (corresponding to pre-implosion external fields of 0.06–10 T) could result in a factor of 2–500 reduction in electron thermal conductivity at the gas-ice interface. The second mechanism to mitigate thermal energy loss from the hot-spot is to decrease the interface mixing area between the hot and cold plasmas. This is achieved through large external magnetic fields of 1000 T at the onset of deceleration which damp short-wavelength RT modes and long-wavelength Kelvin-Helmholtz modes thus significantly slowing the RT growth and reducing mix.
Communication: Virial coefficients and demixing in highly asymmetric binary additive hard-sphere mixtures
Authors: López de Haro Mariano , Tejero Carlos F. , Santos Andrés
Published: April 2013

The problem of demixing in a binary fluid mixture of highly asymmetric additive hard spheres is revisited. A comparison is presented between the results derived previously using truncated virial expansions for three finite size ratios with those that one obtains with the same approach in the extreme case in which one of the components consists of point particles. Since this latter system is known not to exhibit fluid-fluid segregation, the similarity observed for the behavior of the critical constants arising in the truncated series in all instances, while not being conclusive, may cast serious doubts as to the actual existence of a demixing fluid-fluid transition in disparate-sized binary additive hard-sphere mixtures.
Enhanced broadband piezoelectric energy harvesting using rotatable magnets
Authors: Zhou Shengxi , Cao Junyi , Erturk Alper , Lin Jing
Published: April 2013

We investigate a magnetically coupled nonlinear piezoelectric energy harvester by altering the angular orientation of its external magnets for enhanced broadband frequency response. Electromechanical equations describing the nonlinear dynamic behavior include an experimentally identified polynomial for the transverse magnetic force that depends on magnet angle. Up- and down-sweep harmonic excitation tests are performed at constant acceleration over the range of 0–25 Hz. Very good agreement is observed between the numerical and experimental open-circuit voltage output frequency response curves. The nonlinear energy harvester proposed in this work can cover the broad low-frequency range of 4–22 Hz by changing the magnet orientation.
Resonant depletion of photogenerated carriers in InGaAs/GaAs nanowire mats
Authors: De Luca Marta , Polimeni Antonio , Felici Marco , Miriametro Antonio , Capizzi Mario , Mura Francesco , Rubini Silvia , Martelli Faustino
Published: April 2013

Photoluminescence excitation spectra of InGaAs in InGaAs/GaAs heterostructure nanowire mats show clear antiresonances at the critical points of the joint density of states of the GaAs barrier. This remarkable effect arises from resonant light absorption in the upper GaAs segments, with ensuing reduction of photogenerated carriers reaching the lower InGaAs segments. The extent of this effect depends strongly on the excitation geometry of the wires, as well as on their areal density. Our work suggests that a careful design is required for optimal light conversion in nanowire-based solar cell devices.
An experimental study on the impacts of key parameters of all-glass evacuated tubes on the thermal performances of all-glass evacuated tube solar water heaters
Authors: Ma Fangfang , Gao Wenfeng , Liu Tao , Lin Wenxian , Li Ming
Published: April 2013

In this paper, the effects of the stagnation parameter Y, the solar irradiance under stagnation H, and the average heat loss coefficient ULT of individual all-glass evacuated solar collector tubes, which were identified as the major parameters to characterize the thermal performance of the tubes, on the thermal performance of all-glass evacuated tube solar water heaters consisted of such evacuated tubes were investigated by experiments. The experiments were conducted to obtain the heat gain Qs produced by six all-glass evacuated tube solar water heaters with the similar specifications but manufactured by different producers. Each heater consisted of 20 all-glass evacuated solar collector tubes and one tube from each heater was selected randomly to measure its Y, H, and ULT. The experimental results show that both H and ULT have effects on Qs, with Qs decreasing when H or ULT increases, but H has more significant effects on Qs than ULT does. However, Y does not have significant effects on Qs. It is apparent that one effective way to increase the heat gain of an evacuated tube solar water heater is to reduce H and ULT of individual all-glass evacuated solar collector tubes. An error analysis was conducted which clearly shows that the errors caused by the uncertainties associated with the measured Qs, Y, H, and ULT have negligible effects on these results.
Investigation of zinc interstitial ions as the origin of anomalous stress-induced hump in amorphous indium gallium zinc oxide thin film transistors
Authors: Kim Yu-Mi , Jeong Kwang-Seok , Yun Ho-Jin , Yang Seung-Dong , Lee Sang-Youl , Kim Yeong-Cheol , Jeong Jae-Kyeong , Lee Hi-Deok , Lee Ga-Won
Published: April 2013

In this paper, we investigated an anomalous hump in the bottom gate staggered amorphous indium-gallium zinc oxide thin-film transistors. During the positive gate bias stress, a positive threshold voltage shift is observed in transfer curve and an anomalous hump occurs as the stress time increases. The hump becomes more serious as the gate bias stress increases while it is not observed under the negative bias stress. From the simulation of a long range migration of zinc interstitial ions (Zni) and the measurement of the diode characteristics after the constant positive bias stress, the origin of the hump can be explained by the migration of the positively charged mobile Zni during the constant positive gate bias stress, which can be conformed by increasing the concentration of Zni from the result of the Auger ZnL3M4.5M4.5 spectra.
Interactions between perceptions of relationship quality and postnatal depressive symptoms in Australian, primiparous women and their partners
Authors: Wynter Karen , Rowe Heather , Fisher Jane
Published: April 2013

The present study aimed to investigate interactions between perceptions of quality of intimate partner relationship and postnatal depressive symptoms in members of heterosexual couples 6 months after the birth of their first infant, while controlling for other relevant risk and protective factors. Secondary analysis was conducted on data from a prospective community cohort study of Australian, primiparous women and their partners. The outcome measure was Edinburgh Postnatal Depression Scale score. Quality of intimate partner relationship, personality factors and infant behaviour were assessed using the standardised Intimate Bonds Measure, Vulnerable Personality Style Questionnaire and Barr Chart respectively. Complete data were available for 161 couples. Associations between Edinburgh Postnatal Depression Scale scores and own and partner ratings of the intimate partner relationship were estimated simultaneously using multilevel modelling. When other relevant factors were controlled, relationships in which partners were perceived as critical, coercive or intimidating were associated with significantly more depressive symptoms in individuals (P = 0.004) as well as their partners (P = 0.008). In both women and men, vulnerable personality traits, coincidental adverse life events and more infant crying and fussing were also associated with significantly more depressive symptoms. Thus, the quality of the intimate partner relationship is significantly associated with postnatal mental health in both women and men, especially in the context of coincidental stressful events including infant crying.
Challenges and lessons from systematic literature reviews for the Australian dietary guidelines
Authors: Allman-Farinelli Margaret , Byron Annette , Collins Clare , Gifford Janelle , Williams Peter
Published: April 2013

In 2009–10 the Dietitians Association of Australia conducted a series of systematic reviews for the National Health and Medical Research Council to generate evidence statements to inform the revision of the Dietary Guidelines for Australians. In total 202 body of evidence statements were constructed and assigned a grading detailing the certainty with which each could be used to inform policy. This paper describes some of the challenges and insights gained from the process, specifically related to: study type, study quality assessment, the lack of quantified data, diet exposure, definition of a healthy population, generalisability and applicability, and resource allocation. It is clear that there is still a need for further refinement of the methods for evaluating evidence for nutrition policy, but the current dietary guidelines are now much more robustly evidence informed than ever before.
Developmental competence of equine oocytes: impacts of zona pellucida birefringence and maternally derived transcript expression
Authors: Mohammadi-Sangcheshmeh Abdollah , Held Eva , Rings Franca , Ghanem Nasser , Salilew-Wondim Dessie , Tesfaye Dawit , Sieme Harald , Schellander Karl , Hoelker Michael
Published: April 2013

In the present study, equine oocytes were classified into groups of presumably high and low developmental competence according to cumulus morphology, as well as oocyte ability to metabolise brilliant cresyl blue (BCB) stain. All oocytes were evaluated individually in terms of morphometry, zona pellucida birefringence (ZPB) and relative abundance of selected candidate genes. Oocytes with an expanded cumulus (Ex), representing those with presumably high developmental competence, had a significantly thicker zona (18.2 vs 17.3 µm) and a significantly higher ZPB (64.6 vs 62.1) than oocytes with a compacted cumulus (Cp). Concurrently, oocytes classified as highly developmentally competent (BCB+) had a significantly thicker zona (18.8 vs 16.1 µm) and significantly higher ZPB (63.1 vs 61.3) compared with oocytes classified as having low developmental competence. Expression of TFAM, STAT3 and CKS2 was significantly higher in Ex compared with Cp oocytes, whereas expression of COX1, ATPV6E and DNMT1 was lower. Together, the data reveal that developmentally competent equine oocytes are larger in size, have higher ZPB values and exhibit a typical genetic signature of maternally derived transcripts compared with oocytes with lower in vitro developmental competence.
To Stock or Not to Stock? Assessing the Restoration Potential of a Remnant American Shad Spawning Run with Hatchery Supplementation
Authors: Bailey Michael M. , Zydlewski Joseph D.
Published: April 2013

Hatchery supplementation has been widely used as a restoration technique for American Shad Alosa sapidissima on the East Coast of the USA, but results have been equivocal. In the Penobscot River, Maine, dam removals and other improvements to fish passage will likely reestablish access to the majority of this species’ historic spawning habitat. Additional efforts being considered include the stocking of larval American Shad. The decision about whether to stock a river system undergoing restoration should be made after evaluating the probability of natural recolonization and examining the costs and benefits of potentially accelerating recovery using a stocking program. However, appropriate evaluation can be confounded by a dearth of information about the starting population size and age structure of the remnant American Shad spawning run in the river. We used the Penobscot River as a case study to assess the theoretical sensitivity of recovery time to either scenario (stocking or not) by building a deterministic model of an American Shad population. This model is based on the best available estimates of size at age, fecundity, rate of iteroparity, and recruitment. Density dependence was imposed, such that the population reached a plateau at an arbitrary recovery goal of 633,000 spawning adults. Stocking had a strong accelerating effect on the time to modeled recovery (as measured by the time to reach 50% of the recovery goal) in the base model, but stocking had diminishing effects with larger population sizes. There is a diminishing return to stocking when the starting population is modestly increased. With a low starting population (a spawning run of 1,000), supplementation with 12 million larvae annually accelerated modeled recovery by 12 years. Only a 2-year acceleration was observed if the starting population was 15,000. Such a heuristic model may aid managers in assessing the costs and benefits of stocking by incorporating a structured decision framework.

Received December 27, 2011; accepted December 19, 2012
Acclimation Enhances Postrelease Performance of Hatchery Fall Chinook Salmon Subyearlings While Reducing the Potential for Interaction with Natural Fish
Authors: Rosenberger Stuart J. , Connor William P. , Peery Christopher A. , Milks Deborah J. , Schuck Mark L. , Hesse Jay A. , Smith Steven G.
Published: April 2013

One form of prerelease acclimation of hatchery anadromous salmonid Oncorhynchus spp. juveniles is to truck the fish to remote points for extended holding at low densities in rearing vessels (e.g., tanks, raceways, or in-ground ponds) supplied with river water. We conducted a 3-year study to determine whether such acclimation enhanced the postrelease performance of hatchery fall Chinook Salmon O. tshawytscha subyearlings and reduced the potential for interaction with natural fall Chinook Salmon subyearlings. In comparison with hatchery subyearlings that were released directly into the lower Snake River just downstream of the acclimation facility, acclimated hatchery subyearlings (1) passed downstream to Lower Monumental Dam (the third dam encountered during seaward migration) faster, (2) passed the dam earlier, and (3) survived from release to the dam tailrace at higher rates. The differences in downstream passage rate and dam passage timing were also much greater between acclimated hatchery subyearlings and natural subyearlings than between directly released hatchery subyearlings and natural subyearlings. Thus, acclimation provided a survival advantage to the hatchery fish while reducing the potential for (1) aggressive and nonaggressive social interactions with natural fish while in transit through the reservoirs associated with Lower Granite, Little Goose, and Lower Monumental dams; and (2) confinement with natural fish at those three dams, where fish collection and raceway holding were followed by transport in tanker trucks. Our findings support acclimation as a method for enhancing postrelease performance of hatchery fall Chinook Salmon subyearlings and reducing their potential interactions with natural conspecifics.

Received July 25, 2012; accepted January 9, 2013
Disinfection of Three Wading Boot Surfaces Infested with New Zealand Mudsnails
Authors: Stockton Kelly A. , Moffitt Christine M.
Published: April 2013

New Zealand mudsnails Potamopyrgus antipodarum (NZMS) have been introduced into many continents and are easily transported live while attached to wading and other field gear. We quantified the relative attachment by different life stages of NZMS to felt, neoprene, and rubber-soled boots exposed to two densities of NZMS in experimental exposure totes. Attachment by NZMS occurred on boots of all surfaces, but the highest numbers of all life stages occurred on boots with felt surfaces. We found a 15–20-min bath application of 20 g/L Virkon Aquatic was a reliable tool to disinfect boot surfaces infested with NZMS and other aquatic invertebrates. Our studies support that spray application of this disinfectant was not reliable to provide complete mortality of attached adult NZMS or neonates. Wading gear surfaces exposed to repeated bath disinfections showed little deterioration. Our results provide strong evidence that bath disinfections with Virkon Aquatic are helpful to assure biosecurity in field and hatchery settings, but applications should be coupled with cleaning procedures to remove organic materials that can deactivate the reagent.

Received November 11, 2012; accepted January 17, 2013
PUTTING CIRCUITS INTO FIELDS, OR HOW ITALIAN CANZONE GAINED THE STATUS OF ‘ART’ IN THE MUSIC MARKET
Authors: Santoro Marco
Published: April 2013

This article shows how deep moral issues can impinge upon popular culture without this losing its commercial appeal, a process made possible by the role of consecrating institutions in the music market. The article focuses on the fabrication and establishment of a new genre within Italian musical culture and music market, the so-called canzone d'autore, and it is set after the suicide in 1967 of singer-songwriter Luigi Tenco during the most important Italian song festival (Sanremo's Festival della canzone italiana). Drawing upon Zelizer's notion of ‘circuits of commerce’ and Bourdieu's theory of cultural fields, the article will shed some light on the specific dynamics of the interplay between moral issues and commercial appeal in the Italian music market.
Heterochromatin protein 1 promotes self-renewal and triggers regenerative proliferation in adult stem cells
Authors: Zeng An , Li Yong-Qin , Wang Chen , Han Xiao-Shuai , Li Ge , Wang Jian-Yong , Li Dang-Sheng , Qin Yong-Wen , Shi Yufang , Brewer Gary , Jing Qing
Published: April 2013

Adult stem cells (ASCs) capable of self-renewal and differentiation confer the potential of tissues to regenerate damaged parts. Epigenetic regulation is essential for driving cell fate decisions by rapidly and reversibly modulating gene expression programs. However, it remains unclear how epigenetic factors elicit ASC-driven regeneration. In this paper, we report that an RNA interference screen against 205 chromatin regulators identified 12 proteins essential for ASC function and regeneration in planarians. Surprisingly, the HP1-like protein SMED–HP1-1 (HP1-1) specifically marked self-renewing, pluripotent ASCs, and HP1-1 depletion abrogated self-renewal and promoted differentiation. Upon injury, HP1-1 expression increased and elicited increased ASC expression of Mcm5 through functional association with the FACT (facilitates chromatin transcription) complex, which consequently triggered proliferation of ASCs and initiated blastema formation. Our observations uncover an epigenetic network underlying ASC regulation in planarians and reveal that an HP1 protein is a key chromatin factor controlling stem cell function. These results provide important insights into how epigenetic mechanisms orchestrate stem cell responses during tissue regeneration.
The level of origin firing inversely affects the rate of replication fork progression
Authors: Zhong Yuan , Nellimoottil Tittu , Peace Jared M. , Knott Simon R.V. , Villwock Sandra K. , Yee Janis M. , Jancuska Jeffrey M. , Rege Sanket , Tecklenburg Marianne , Sclafani Robert A. , Tavaré Simon , Aparicio Oscar M.
Published: April 2013

DNA damage slows DNA synthesis at replication forks; however, the mechanisms remain unclear. Cdc7 kinase is required for replication origin activation, is a target of the intra-S checkpoint, and is implicated in the response to replication fork stress. Remarkably, we found that replication forks proceed more rapidly in cells lacking Cdc7 function than in wild-type cells. We traced this effect to reduced origin firing, which results in fewer replication forks and a consequent decrease in Rad53 checkpoint signaling. Depletion of Orc1, which acts in origin firing differently than Cdc7, had similar effects as Cdc7 depletion, consistent with decreased origin firing being the source of these defects. In contrast, mec1-100 cells, which initiate excess origins and also are deficient in checkpoint activation, showed slower fork progression, suggesting the number of active forks influences their rate, perhaps as a result of competition for limiting factors.
TMEM16F (Anoctamin 6), an anion channel of delayed Ca2+ activation
Authors: Grubb Søren , Poulsen Kristian A. , Juul Christian Ammitzbøll , Kyed Tania , Klausen Thomas K. , Larsen Erik Hviid , Hoffmann Else K.
Published: April 2013

Members of the TMEM16 (Anoctamin) family of membrane proteins have been shown to be essential constituents of the Ca2+-activated Cl− channel (CaCC) in many cell types. In this study, we have investigated the electrophysiological properties of mouse TMEM16F. Heterologous expression of TMEM16F in HEK293 cells resulted in plasma membrane localization and an outwardly rectifying ICl,Ca that was activated with a delay of several minutes. Furthermore, a significant Na+ current was activated, and the two permeabilities were correlated according to PNa = 0.3 PCl. The current showed an EC50 of 100 µM intracellular free Ca2+ concentration and an Eisenman type 1 anion selectivity sequence of PSCN > PI > PBr > PCl > PAsp. The mTMEM16F-associated ICl,Ca was abolished in one mutant of the putative pore region (R592E) but retained in two other mutants (K616E and R636E). The mutant K616E had a lower relative permeability to iodide, and the mutant R636E had an altered anion selectivity sequence (PSCN = PI = PBr = PCl > PAsp). Our data provide evidence that TMEM16F constitutes a Ca2+-activated anion channel or a pore-forming subunit of an anion channel with properties distinct from TMEM16A.
Quantitative properties and receptor reserve of the DAG and PKC branch of Gq-coupled receptor signaling
Authors: Falkenburger Björn H. , Dickson Eamonn J. , Hille Bertil
Published: April 2013

Gq protein–coupled receptors (GqPCRs) of the plasma membrane activate the phospholipase C (PLC) signaling cascade. PLC cleaves the membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2) into the second messengers diacylgycerol (DAG) and inositol 1,4,5-trisphosphate (IP3), leading to calcium release, protein kinase C (PKC) activation, and in some cases, PIP2 depletion. We determine the kinetics of each of these downstream endpoints and also ask which is responsible for the inhibition of KCNQ2/3 (KV7.2/7.3) potassium channels in single living tsA-201 cells. We measure DAG production and PKC activity by Förster resonance energy transfer–based sensors, and PIP2 by KCNQ2/3 channels. Fully activating endogenous purinergic receptors by uridine 5′triphosphate (UTP) leads to calcium release, DAG production, and PKC activation, but no net PIP2 depletion. Fully activating high-density transfected muscarinic receptors (M1Rs) by oxotremorine-M (Oxo-M) leads to similar calcium, DAG, and PKC signals, but PIP2 is depleted. KCNQ2/3 channels are inhibited by the Oxo-M treatment (85%) and not by UTP (<1%), indicating that depletion of PIP2 is required to inhibit KCNQ2/3 in response to receptor activation. Overexpression of A kinase–anchoring protein (AKAP)79 or calmodulin (CaM) does not increase KCNQ2/3 inhibition by UTP. From these results and measurements of IP3 and calcium presented in our companion paper (Dickson et al. 2013. J. Gen. Physiol. http://dx.doi.org/10.1085/jgp.201210886), we extend our kinetic model for signaling from M1Rs to DAG/PKC and IP3/calcium signaling. We conclude that calcium/CaM and PKC-mediated phosphorylation do not underlie dynamic KCNQ2/3 channel inhibition during GqPCR activation in tsA-201 cells. Finally, our experimental data provide indirect evidence for cleavage of PI(4)P by PLC in living cells, and our modeling revisits/explains the concept of receptor reserve with measurements from all steps of GqPCR signaling.
Conservation and de novo acquisition of dosage compensation on newly evolved sex chromosomes in Drosophila
Authors: Alekseyenko Artyom A. , Ellison Christopher E. , Gorchakov Andrey A. , Zhou Qi , Kaiser Vera B. , Toda Nick , Walton Zaak , Peng Shouyong , Park Peter J. , Bachtrog Doris , Kuroda Mitzi I.
Published: April 2013

Dosage compensation has arisen in response to the evolution of distinct male (XY) and female (XX) karyotypes. In Drosophila melanogaster, the MSL complex increases male X transcription approximately twofold. X-specific targeting is thought to occur through sequence-dependent binding to chromatin entry sites (CESs), followed by spreading in cis to active genes. We tested this model by asking how newly evolving sex chromosome arms in Drosophila miranda acquired dosage compensation. We found evidence for the creation of new CESs, with the analogous sequence and spacing as in D. melanogaster, providing strong support for the spreading model in the establishment of dosage compensation.
Structure–function studies of STAR family Quaking proteins bound to their in vivo RNA target sites
Authors: Teplova Marianna , Hafner Markus , Teplov Dmitri , Essig Katharina , Tuschl Thomas , Patel Dinshaw J.
Published: April 2013

Mammalian Quaking (QKI) and its Caenorhabditis elegans homolog, GLD-1 (defective in germ line development), are evolutionarily conserved RNA-binding proteins, which post-transcriptionally regulate target genes essential for developmental processes and myelination. We present X-ray structures of the STAR (signal transduction and activation of RNA) domain, composed of Qua1, K homology (KH), and Qua2 motifs of QKI and GLD-1 bound to high-affinity in vivo RNA targets containing YUAAY RNA recognition elements (RREs). The KH and Qua2 motifs of the STAR domain synergize to specifically interact with bases and sugar-phosphate backbones of the bound RRE. Qua1-mediated homodimerization generates a scaffold that enables concurrent recognition of two RREs, thereby plausibly targeting tandem RREs present in many QKI-targeted transcripts. Structure-guided mutations reduced QKI RNA-binding affinity in vitro and in vivo, and expression of QKI mutants in human embryonic kidney cells (HEK293) significantly decreased the abundance of QKI target mRNAs. Overall, our studies define principles underlying RNA target selection by STAR homodimers and provide insights into the post-transcriptional regulatory function of mammalian QKI proteins.
Preparedness: the state of the art and future prospects
Authors: Hémond Yannick , Robert Benoît
Published: April 2013

Purpose

The purpose of this paper is to show the evolution of the concept “state of preparedness” into “state of resilience” in the context of emergency management, and the implications raised by this new concept.

Design/methodology/approach

This paper is a literature review (scientific and governmental) of the most important articles in the field of state of preparedness evaluation.

Findings

This article presents two trends in the state of preparedness evaluation: response capability and preparation management. These two trends contribute to the evolution of the concept “state of preparedness” into “state of resilience”, a state that is defined as the ability of a system to maintain or restore an acceptable level of functioning despite disruptions and failures.

Originality/value

This literature review helps define the concept of “state of preparedness” (in terms of both management and response capability) as the new trend of resilience.
Characteristics and influences of H1N1 communication on college students
Authors: Koskan Alexis , Foster Caroline , Karlis Jack , Rose India , Tanner Andrea
Published: April 2013

Purpose

The purpose of this paper is to assess how college students received and responded to H1N1 pandemic emergency preparedness information and to assess college students’ knowledge and attitudes towards H1N1 during the height of the H1N1 epidemic and corresponding public health response to the outbreak.

Design/methodology/approach

Using a case study approach, the researchers conducted five focus groups at a large Southeastern US university between October 20‐29, 2009.

Findings

In order to effectively communicate emergency preparedness information to college students, universities should rely on interpersonal communication and mediated communication from trusted sources. College students need to understand the health‐related emergency, the risk of the emergency, basic steps to avoid it, and only pertinent cues to action. Oversaturation of this information can lead college students to lessen their perceived importance of the disaster prevention information.

Research limitations/implications

Focus groups were conducted during only two consecutive weeks of the H1N1 epidemic, and snowball sampling may have led to sample bias.

Originality/value

This research was conducted during the height of the H1N1 pandemic, and is the only study to date that explores college students’ knowledge, attitudes, and behaviors towards H1N1.
Effectiveness of educational tools for hurricane resilience in homes
Authors: Strayhorn Tyler , Dasmohapatra Sudipta , Tilotta Dave , Mitchell Phil
Published: April 2013

Purpose

In the disaster mitigation community, one of the most important tasks is that of information transfer prior to, and following natural disasters. The purpose of this research project was to increase the understanding of key aspects (such as attractiveness and educational value) that influence the utility and effectiveness of educational media tools for home resilience during hurricanes.

Design/methodology/approach

A total of three types of educational media were developed – pulp board coasters, tri‐fold pamphlets, and a web hosted video. The contents of these media were developed based on data from federal agencies, as well as scholarly articles and technical reports to form an inclusive body of information. Several focus groups of homeowners and potential homeowners were held to evaluate participant's preference of these three media tools with regards to their usefulness for making homes safer during natural disasters, specifically during wind and wind‐driven rain events (e.g. hurricanes).

Findings

Analysis of the focus groups indicate that media use (based on disaster prevention home resilience practices) is highly dependent on the target audience or the stakeholder group (e.g. consumers look for different information content as compared to the builders). While all three media were indicated by the participants to have merit, the pamphlet was preferred aesthetically and was most likely to be used by homeowners. In addition, the study found that the usefulness of the tools depends on the ease of understanding and implementation of the best practices and ease of access to the tools (targeted location for each media).

Research limitations/implications

The findings of the study have implications for the entire disaster educational community. Although the findings are mostly qualitative and the small sample used in the focus groups limits the generalize ability to the entire population of the USA, nevertheless, future educational information and tools used should follow easy to understand language, be illustrated with examples and pictures, and be placed at convenient locations for homeowners to access.

Originality/value

By understanding how to better reach homeowners with information on home resilience, information can be more effectively disseminated to the public which allows for efficient use of tools as well as funds.
Resilience and adaptation of small and medium‐sized enterprises to flood risk
Authors: Wedawatta Gayan , Ingirige Bingunath
Published: April 2013

Purpose

The UK has experienced a number of flood events in recent years, and the intensity and frequency of such events are forecast to further increase in future due to changing climatic conditions. Accordingly, enhancing the resilience of small and medium‐sized enterprises (SMEs) – which form an important segment in a society – to flood risk, has emerged as an important issue. However, SMEs often tend to underestimate the risk of flooding which tends to have a low priority in their business agenda. The purpose of this paper is to undertake an investigation of adaptation to the risk of flooding considering community‐level measures, individual‐level property protection, and business continuity and resilience measures.

Design/methodology/approach

A total of four short case studies were conducted among SMEs to identify their response to flood risk, and what measures have been undertaken to manage the risk of flooding.

Findings

It was observed that SMEs have implemented different property‐level protection measures and generic business continuity/risk management measures, based on their requirements, to achieve a desired level of protection.

Practical implications

SMEs are likely to positively respond to property‐level adaptation following a post‐flood situation. It is important that information such as costs/benefits of such measures and different options available are made accessible to SMEs affected by a flood event.

Social implications

Implementation of property‐level adaptation measures will contribute towards the long term adaptation of the existing building stock to changing climatic conditions.

Originality/value

The paper contributes towards policy making on flood risk adaptation and SME decision making, and informs policy makers and practitioners.
Disaster management in Cameroon: the Lake Nyos disaster experience
Authors: Ngenyam Bang Henry
Published: April 2013

Purpose

The purpose of this paper is to review critically, how the Lake Nyos disaster (LND), which occurred in 1986, is being managed by examining the immediate post disaster management and long‐term management. It reveals how the disaster management system in Cameroon influences the management style and process with regards to the technical and socio‐economic management of LND.

Design/methodology/approach

Qualitative research methods for empirical and secondary data were adopted in the study, including interviews (with disaster managers and LND survivors) and reviews of policy documents and media reports. Triangulation of information sources in the analysis has been done to enhance credibility.

Findings

While significant progress has been made in technical management of LND, the socio‐economic management has been poor. Although this can be partly attributed to the weak financial situation of Cameroon, the major problems seem to be related to human systems.

Practical implications

The disaster management has focused mainly on technical and structural mitigation measures with less consideration of non‐structural measures. This has had dire consequences for the displaced disaster survivors. A major challenge still lies in tackling social vulnerability within the displaced disaster population.

Originality/value

This paper provides a comprehensive analysis of contemporary challenges facing the management of LND. This paper is important because published information on socio‐economic aspects of LND is very scarce. This paper is part of a larger research that was conducted for a PhD in the UK.
Emergency communications and warning systems
Authors: Martin Nigel , Rice John
Published: April 2013

Purpose

The frequent occurrence of emergencies and disasters continues to threaten community safety and security. Emergency communications and warning systems (ECWS) allow people to make decisions and take actions before, during and after the emergency or disaster. The critical objective of this study is to determine the critical capacities of ECWS in the Australian context.

Design/methodology/approach

This study used stakeholder analysis in which written submissions from individuals, and public and private organizations collected by the Australian federal government were subjected to structured coding techniques in order to identify major ECWS capacity issues. The summary of findings were generating by axially collapsing and summarizing the coded statements.

Findings

Findings showed that a broad range of ECWS are deployed in the Australian context. These ECWS come with social and/or technical limitations that suggest the importance of adopting an integrated or systems based approach for their construction and deployment. Also, while the identification of critical infrastructure vulnerabilities reinforced the argument for an integrated systems approach for ECWS, this also demonstrated the pressing need to build resilience and redundancy into domestic infrastructure networks. In addition, new and innovative ECWS technologies and solutions will enable improved emergency or disaster management in the future.

Originality/value

This paper simultaneously considers important factors and issues impacting ECWS and provides an instructive discourse on the requirement for more combinative ECWS.
Influence of physical ability on initial emergency response performance
Authors: Subramaniam Chandrakantan , Ali Hassan , Mohd Shamsudin Faridahwati
Published: April 2013

Purpose

This paper aims to determine the influence of physical ability on initial emergency response performance among emergency response teams.

Design/methodology/approach

In an emergency incident, emergency responders are involved in vigorous physical activities. Previous attempts have demonstrated that job performance of emergency responders depends a great deal on their ability to perform strenuous physical activity. This paper examines the influence of physical ability namely weight, height, and cardiovascular endurance on emergency response performance among fire fighting teams in Malaysia. Emergency response performance was defined as team member's speed in responding to emergency situations. Data on team member's physical ability and emergency response time were collected for the duration of five months. The distance from the waiting room to the fire truck in each selected fire station was used to measure performance.

Findings

This study found that the team with higher average weight and cardiovascular endurance level had better initial response to emergency situations, contrary to the research hypothesis. But it is speculated that the relationship could be further understood by considering the proportion of fat in the body. The relationship between cardiovascular endurance and initial emergency response performance further validates and justifies the use of physical fitness test as a criterion for job performance of fire fighters.

Originality/value

This paper offers empirical evidence of emergency response performance in Malaysia. Specifically, it presents findings on the influence of physical ability measures on initial emergency response performance from a team perspective. In addition, the emergency response performance was measured by the distance traveled by the responders, which serves as a meaningful performance indicator.