bluuebunny/crossref_metadata_2025 huggingface dataset:
POST-ABORTION CARE SERVICES FOR YOUTH AND ADULT CLIENTS IN KENYA: A COMPARISON OF SERVICES, CLIENT SATISFACTION AND PROVIDER ATTITUDES
Authors: EVENS EMILY , OTIENO-MASABA ROSE , EICHLEAY MARGARET , McCARRAHER DONNA , HAINSWORTH GWYN , LANE CATE , MAKUMI MARGARET , ONDUSO PAMELA
Published: June 2013

Unsafe abortion accounts for 35% of maternal mortality in Kenya. Post-abortion care (PAC) reduces maternal death and provides an opportunity to prevent unwanted pregnancies. Few studies have documented how the receipt of PAC services varies by client age. In this study, descriptive data were collected from clients, providers and eight health facilities in Kenya's Central and Nairobi provinces to examine receipt of PAC services by client age, client satisfaction and provider attitudes. Delivery of PAC treatment, pain management, HIV and STI services and violence screening did not vary by age. However, fewer youth between the ages of 15 and 24 received a contraceptive method compared with adult clients (35% versus 48%; p=0.02). Forty-nine per cent of youth reported not using a family planning method due to fears of infertility, side-effects or lack of knowledge compared with 22% of adults. Additional efforts are needed in Kenya to bolster the family planning services that young PAC clients receive and increase the uptake of contraception.
The Benefactor's Account-book: The Rhetoric of Gift Reciprocation according to Seneca and Paul
Authors: Blanton Thomas R.
Published: June 2013

According to Seneca, a cardinal rule of benefaction is that the donor of a gift ought never to call attention to the fact that a gift has been given; it humiliates the donee and shames the donor. In reminding Philemon that he ‘owes’ Paul for the latter's mediation of the gift of salvation (Phlm 19), Paul breaks Seneca's rule. Both Seneca's ‘virtuous’ advice and Paul's ‘shameful’ breach of etiquette, however, are explicable as strategies calculated to maximize their access to valued goods and services—whether honor or the services of a wealthier man's slave—inflected by vastly different economic situations.
Justification, Good Works, and Creation in Clement of Rome's Appropriation of Romans 5–6
Authors: Downs David J.
Published: June 2013

In 1 Clement32–33, Romans 5–6 is alluded to in a summary statement concerning justification by faith (32.4), followed by two rhetorical questions that stress the ethical implications of this confession (33.1). These allusions to Romans are punctuated by an appeal for readers to imitate the pattern of good works established by God during creation (33.2-8). This article contends that the difference between Romans 5–6 and one of the earliest Christian readings of these chapters is not accidental, for the ethical appeal in 1 Clement33 reflects the author's distinct cosmological perspective and rhetorical aims.
The Improper Temple Offering of Ananias and Sapphira
Authors: Le Donne Anthony
Published: June 2013

In Acts 1–7, the Holy Spirit functions as the restored temple presence of the Lord that will restore the kingdom to Israel via theEkklesia. The Holy Spirit acts through theEkklesiaas one would expect the Lord's temple presence to act. When Barnabas, Ananias, and Sapphira bring their offerings to the temple, they place them at the feet of the leadership of the new religio-fiscal center of restored Israel. As proof that the Lord's presence has indwelled this eschatological temple community, an improper act can, and does in this case, result in immediate death.
Passover and Last Supper Revisited
Authors: Marcus Joel
Published: June 2013

Although Jesus' Last Supper probably took place on the night before Passover (as in John) rather than on the first night of Passover itself (as in the Synoptics), it contained elements strongly marked by the Jewish institution of the Passover seder (fixed order of service) and haggadah (ritual retelling of the exodus events). These elements were not, as some scholars of Judaism have recently argued, post-70 CE developments. Rather, evidence fromJubilees, Philo, and the NT itself indicates that seder and haggadah already existed in some form in the pre-70 period.
Parent–child conflict as an etiological moderator of childhood conduct problems: an example of a ‘bioecological’ gene–environment interaction
Authors: Burt S. A. , Klump K. L.
Published: June 2013

Background

Prior research has suggested that, consistent with the diathesis–stress model of gene–environment interaction (G × E), parent–child conflict activates genetic influences on antisocial/externalizing behaviors during adolescence. It remains unclear, however, whether this model is also important during childhood, or whether the moderation of child conduct problems by negative/conflictive parenting is better characterized as a bioecological interaction, in which environmental influences are enhanced in the presence of environmental risk whereas genetic influences are expressed most strongly in their absence. The current study sought to distinguish between these possibilities, evaluating how the parent–child relationship moderates the etiology of childhood-onset conduct problems.

Method

We conducted a series of ‘latent G by measured E’ interaction analyses, in which a measured environmental variable was allowed to moderate both genetic and environmental influences on child conduct problems. Participants included 500 child twin pairs from the Michigan State University Twin Registry (MSUTR).

Results

Shared environmental influences on conduct problems were found to be several-fold larger in those with high levels of parent–child conflict as compared with those with low levels. Genetic influences, by contrast, were proportionally more influential at lower levels of conflict than at higher levels.

Conclusions

Our findings suggest that, although the diathesis–stress form of G × E appears to underlie the relationship between parenting and conduct problems during adolescence, this pattern of moderation does not extend to childhood. Instead, results were more consistent with the bioecological form of G × E which postulates that, in some cases, genetic influences may be most fully manifested in the absence of environmental risk.
Protein partners of dynamin-1 in the retina
Authors: GROSSMAN GREGORY H. , EBKE LINDSEY A. , BEIGHT CRAIG D. , JANG GEENG-FU , CRABB JOHN W. , HAGSTROM STEPHANIE A.
Published: June 2013

Dynamin proteins are involved in vesicle generation, providing mechanical force to excise newly formed vesicles from membranes of cellular compartments. In the brain, dynamin-1, dynamin-2, and dynamin-3 have been well studied; however, their function in the retina remains elusive. A retina-specific splice variant of dynamin-1 interacts with the photoreceptor-specific protein Tubby-like protein 1 (Tulp1), which when mutated causes an early onset form of autosomal recessive retinitis pigmentosa. Here, we investigated the role of the dynamins in the retina, using immunohistochemistry to localize dynamin-1, dynamin-2, and dynamin-3 and immunoprecipitation followed by mass spectrometry to explore dynamin-1 interacting proteins in mouse retina. Dynamin-2 is primarily confined to the inner segment compartment of photoreceptors, suggesting a role in outer segment protein transport. Dynamin-3 is present in the terminals of photoreceptors and dendrites of second-order neurons but is most pronounced in the inner plexiform layer where second-order neurons relay signals from photoreceptors. Dynamin-1 appears to be the dominant isoform in the retina and is present throughout the retina and in multiple compartments of the photoreceptor cell. This suggests that it may function in multiple cellular pathways. Surprisingly, dynamin-1 expression and localization did not appear to be disrupted in tulp1−/− mice. Immunoprecipitation experiments reveal that dynamin-1 associates primarily with proteins involved in cytoskeletal-based membrane dynamics. This finding is confirmed by western blot analysis. Results further implicate dynamin-1 in vesicular protein transport processes relevant to synaptic and post-Golgi pathways and indicate a possible role in photoreceptor stability.
Using nonsense words to investigate vowel merger
Authors: HAY JENNIFER , DRAGER KATIE , THOMAS BRYNMOR
Published: June 2013

In previous work, we have found that New Zealand listeners who produce merged tokens of near and square can accurately distinguish between the vowels in perception even though they report that they are guessing. The ability to distinguish the vowels is affected by a variety of factors for these listeners, including the likelihood that the speaker and experimenter maintain the distinction (Hay et al. 2006b; Hay et al. 2010). In this article, we report on experiments that examine the production and perception of real and nonsense words in the context of two mergers: the Ellen/Allan merger in New Zealand English and the lot/thought merger found in American English. The results demonstrate that speakers’ degree of merger depends at least partially on whether the word is a real or nonsense word. Additionally, the results indicate that a token's real word status affects the merger differently in production and perception. We argue that these results provide evidence in favour of a hybrid model of speech production and perception, one with both abstract phoneme-level representations and acoustically detailed episodic representations.
How salient is thenurse~squaremerger?
Authors: WATSON KEVIN , CLARK LYNN
Published: June 2013

This article reports the results of an experimental investigation into listeners' evaluative reactions towards thenurse~squaremerger in the north-west of England, in an attempt to shed light on its salience. Although speakers across England's north-west have anurse~squaremerger, its realisation differs: in Liverpool, speakers typically merge to a mid front [ɛː], while speakers from St Helens, just 20km further east, merge to a mid central [ɜː]. To test listeners' responses to each variant, we presented two groups of listeners from each of these localities with read sentence data from a single speaker. The speaker was from the north-west of England and had a centralisednurse~squarevowel in his native accent (representing the St Helens model). To achieve a matched-guise, the originalnurse~squarevowels were acoustically manipulated to give the impression of fronting (representing the Liverpool model). Listeners from Liverpool and St Helens were asked to react to guises along the status dimension, and their reaction was measured in real-time using bespoke audience response software administered via the web. The novelty in this approach is that it can be used not only to show that listeners do indeed react to the guises, but also to examine preciselywhenthis reaction takes place. Our results show that (a) overall, speakers with anurse~squaremerger are not rated highly on the status dimension, regardless of whether they have a merger to a front or central vowel; (b) listeners' real-time reactions can be correlated with instances ofnurseandsquare; and (c) listeners' responses tonursecan be different from responses tosquare.We discuss these results in relation to the salience of this merger in particular and to salience in general. We suggest that the salience ofnurseandsquareis related to the local social context and the micro-linguistic context in which they appear.
New contrast acquisition: methodological issues and theoretical implications
Authors: NYCZ JENNIFER
Published: June 2013

This article presents data on the acquisition of the low back vowel contrast by native speakers of Canadian English who have moved as adults to the New York City region, examining how these speakers who natively possess a single low back vowel category have acquired the low back vowel distinction of the new ambient dialect. The speakers show remarkable first dialect stability with respect to their low back vowel system, even after many years of new dialect exposure: in minimal pair contexts, nearly all of the speakers continue to produce and perceive a single vowel category. However, in word list and conversational contexts, the majority of speakers exhibit a small but significant phonetic difference between words likecotandcaught, reflecting the separation of these word classes in the new dialect to which they are exposed; moreover, the realization of these words shows frequency effects consistent with a lexically gradual divergence of the two vowels. These findings are discussed in terms of their implications for theories of phonological representation and change, as well as their methodological implications for the study of mergers- and splits-in-progress.
‘Flip-flop’ and mergers-in-progress
Authors: HALL-LEW LAUREN
Published: June 2013

During a merger-in-progress, occasionally one or two speakers will exhibit an unusual phonological pattern reminiscent offlip-flop(Labovet al. 1972). In such cases, the merging vowels appear to move past the point of coalescence in at least one phonetic dimension; difference is maintained but the vowel quality is opposite to the historical pattern on one or both dimensions. Flip-flop between thecotandcaughtvowels occurs for two speakers in a recent sample from San Francisco, California. The community shows robust change in progress toward a lower and frontercaughtvowel nucleus, and no change in apparent time forcot. Further analysis shows that this is leading to a change in apparent time toward merger, and that the rate of vowel convergence is stronger among Chinese Americans than European Americans. The two speakers who produce flip-flop are seen to represent a key transitional generation with respect to the ethnic identity of the neighborhood, where flip-flop may be but one linguistic consequence of a lifetime of active negotiation between conflicting local meanings. The analysis suggests that ethnographic detail and attention to individual outliers allows for more comprehensive models of the range of phenomena associated with vowel mergers.
W. E. B. AND SHIRLEY GRAHAM DU BOIS IN MAOIST CHINA
Authors: Gao Yunxiang
Published: June 2013

Using previously untranslated Chinese sources, this article adds dimension and insight into the visits of W. E. B. and Shirley Graham Du Bois to the People's Republic of China in 1959 and 1963. After discussing Du Bois's earlier writings and visit to China in 1936, the article reveals the Chinese Communist Party's (CCP) awareness of Du Bois's favorable commentary on the nation during the 1950s. Using articles from thePeople's Daily(Renmin ribao) and other Chinese sources, I argue that the CCP and the Du Boises gained mutual benefit from the visit outside of the “arranged reality” of such political tourism. The CCP gained increased legitimacy among African nations as a nation of color. Du Bois widened his famous dictum about the importance of the color line in the twentieth century to include Asians. In a preface to a 1959 Chinese translation of theSouls of Black Folk(published to commemorate his visit), Du Bois amended his argument about the color line to emphasize the international struggle of the working classes. In addition to discussion on W. E. B. Du Bois's writings about China following the 1959 visit, I focus on Shirley Graham Du Bois's interactions with the Chinese, their knowledge of her scholarship about Paul Robeson, the celebrated Black American singer, actor, and communist, and her politically sympathetic actions toward China. After the death of her husband, Graham Du Bois sustained involvement with China throughout the Cultural Revolution until her death in 1977 and interment in theBabaoshanCemetery for Revolutionary Heroes in Beijing. Her burial fixed an appropriate identity with China. While her husband's grave site was in Ghana, an unfriendly military government controlled that nation and the United States was no longer her home country. China became her permanent home.
“A FIGURE OF OUR TIMES”
Authors: Buschendorf Christa , West Cornel
Published: June 2013

This interview is part of a larger project on the Black prophetic tradition and its impact on today's ongoing struggle for justice and equality. We are concerned with the special challenges facing Black public intellectuals and activists, particularly with the impediments deriving from their position as outsiders in society; we consider the philosophical and political voices that helped form their own thinking as well as the social conditions that shaped them; and we reflect on the role of religion in their lives and its specific function in the Black community.2
RACIAL/ETHNIC DISPARITIES IN INFANT MORTALITY AMONG U.S. LATINOS
Authors: Henry-Sanchez Brenda L. , Geronimus Arline T.
Published: June 2013

Despite shared colonization histories between the United States and Latin America, research examining racial disparities in health in the United States has often neglected Latinos. Additionally, descendants from Latin America residing in the United States are often categorized under the pan-ethnic label of Hispanic or Latino. This categorization obscures the group's heterogeneity, which is illuminated by research showing consistent differences in health for the three largest segments of the Latino population—Mexicans, Puerto Ricans, and Cubans. We examine whether the patterns of infant mortality associated with race in the non-Latino population also follow for Latinos. We also examine whether we can attribute patterns of infant mortality between the three largest Latino sub-groups to a process we termsegmented racialization. We find that race operates for Latinos the same way it does for the non-Latino population and that there seems to be some evidence to support our segmented racialization hypothesis. The results point to the need to abandon the practices of combining Latino sub-groups as well as ignoring the racial diversity within the Latino population in health research.
RACIAL INCLUSION OR ACCOMMODATION?
Authors: Okamoto Dina , Gast Melanie Jones
Published: June 2013

In this paper, we examine how community-based organizations (CBOs) and their leaders negotiate and expand the boundaries of the communities they serve and represent. Drawing upon interviews with organizational leaders and documentary data from Asian American CBOs in the San Francisco Bay Area, we find that nearly all of the organizations in our sample engaged in cross-racial work, incorporating other racial groups into their programs, campaigns, and partnerships. However, leaders varied in how they understood this work as tied to maintaining or expanding their community of focus. The majority of the leaders in our sample discussed cross-racial work as a way to accommodate other racial groups while maintaining a focus on Asian Americans or Asian-ethnics. Other leaders included other racial groups, mainly Latinos and African Americans, in expanded missions and goals, broadening not only resources and collective action efforts, but also community boundaries through racial inclusion. We argue that pressures and incentives related to funding, shared interests, and organizational survival may encourage CBOs to engage in cross-racial work, but these factors do not necessarily sustain racial inclusion over time. Instead, how leaders identify and construct a sense of expanded group boundaries for the community that they serve and represent helps an organization to commit to racial inclusion.
THE ANTINOMIES OF RACIAL CHANGE
Authors: Bobo Lawrence D.
Published: June 2013

Discussions of complexity and change in matters of ethnoracial relations often obscure as much as they describe and illuminate. In part, this is so because such distinctions, racial ones in particular, are not now nor have they ever been fixed, static, and natural categories. They are instead malleable social constructions. In part, it is so because expressly ideological projects are typically embedded within the claims scholars make about ethnoracial patterns. Consider the assertion that hybridity and mixture are ending the relevance of race, or that global population flows, massive immigration, and “super-diversity” will, likewise, render notions of race passé. The trouble here is that the crossing of socially imposed lines of race and ethnicity, as well as contact among diverse peoples, has long characterized the human experience.
Gender differences in intimate partner violence and psychiatric disorders in England: results from the 2007 adult psychiatric morbidity survey
Authors: Jonas S. , Khalifeh H. , Bebbington P. E. , McManus S. , Brugha T. , Meltzer H. , Howard L. M.
Published: June 2013

Aims.

To assess the extent to which being a victim of intimate partner violence (IPV) is associated with psychiatric disorders in men and women.

Methods.

A stratified multistage random sample was used in the third English psychiatric morbidity survey. Psychiatric disorders were measured by the Clinical Interview Schedule (Revised) and screening questionnaires. IPV was measured using British Crime Survey questions.

Results.

18.7% (95% CI 17.1–20.4; n = 595 of 3197) of men had experienced some form of IPV compared with 27.8% of women (95% CI 26.2–29.4; n = 1227 of 4206; p < 0.001). IPV was associated with all disorders measured (except eating disorders in men). Physical IPV was significantly linked to psychosis and with substance and alcohol disorders in men and women, but significant associations with common mental disorders (CMDs), post-traumatic stress disorder (PTSD) and eating disorders were restricted to women. Emotional IPV was associated with CMDs in men and women.

Conclusions.

The high prevalence of experiences of partner violence, and strength of the association with every disorder assessed, suggests enquiry about partner violence is important in identifying a potential risk and maintenance factor for psychiatric disorders, and to ascertain safety, particularly in women as they are at greatest risk of being victims of violence.
Age Differences in Executive Functions within a Sample of Brazilian Children and Adolescents
Authors: Dias Natália Martins , Menezes Amanda , Seabra Alessandra Gotuzo
Published: June 2013

Executive abilities have been suggested to show differential age-related changes. This study aimed to extend this evidence to a Brazilian sample, which was composed of 572 children and adolescents aged 6 to 14 years, assessed in tests of visual and auditory working memory, selective attention, inhibitory control, cognitive flexibility, attentional abilities, verbal fluency and planning. ANOVAs revealed significant age effect on performance in all tests, with a trend toward better performance with the progression of age, even in differential ways. Overall, the performance on simpler tests, such as the basic attention, increased with age progression until around 11 or 12 years, when performance becomes more stable. However, in more complex tasks, including working memory tasks, the performance showed a more continuous improvement. There was gender effect in two measures: visual working memory, in which boys outperformed girls, and verbal fluency, in which the girls outperformed boys. In general, the results of this Brazilian sample were similar to those reported by studies conducted in other countries, what suggests that Brazilian socio-cultural specificities, at least of the participants of this sample, were not sufficient to reveal a distinct pattern of progression.
Hsp104 as a key modulator of prion-mediated oxidative stress in Saccharomyces cerevisiae
Authors: Singh Kuljit , Saleh Aliabbas A. , Bhadra Ankan K. , Roy Ipsita
Published: June 2013

Maintenance of cellular redox homoeostasis forms an important part of the cellular defence mechanism and continued cell viability. Despite extensive studies, the role of the chaperone Hsp104 (heat-shock protein of 102 kDa) in propagation of misfolded protein aggregates in the cell and generation of oxidative stress remains poorly understood. Expression of RNQ1-RFP in Saccharomyces cerevisiae cells led to the generation of the prion form of the protein and increased oxidative stress. In the present study, we show that disruption of Hsp104 in an isogenic yeast strain led to solubilization of RNQ1-RFP. This reduced the oxidative stress generated in the cell. The higher level of oxidative stress in the Hsp104-containing (parental) strain correlated with lower activity of almost all of the intracellular antioxidant enzymes assayed. Surprisingly, this did not correspond with the gene expression analysis data. To compensate for the decrease in protein translation induced by a high level of reactive oxygen species, transcriptional up-regulation takes place. This explains the discrepancy observed between the transcription level and functional enzymatic product. Our results show that in a ΔHsp104 strain, due to lower oxidative stress, no such mismatch is observed, corresponding with higher cell viability. Thus Hsp104 is indirectly responsible for enhancing the oxidative stress in a prion-rich environment.
On the connection of semiclassical instanton theory with Marcus theory for electron transfer in solution
Authors: Shushkov Philip
Published: June 2013

We present a derivation of Marcus theory of electron transfer in solution starting from semiclassical instanton theory. The conventional semiclassical instanton theory provides an inadequate description of the electron transfer process in the inverted Marcus regime. This has been attributed to the lack of backscattering in the product region, which is represented as a semi-infinite continuum of states. For electron transfer processes in condensed phase, the electronic states in the acceptor well are bound, which violates the continuum assumption. We show by detailed analysis of the minimum action path of a model system for electron transfer that the proper tunneling coordinate is a delocalized, “bead-count” mode. The tunneling mode is analytically continued in the complex plane as in the traditional derivation. Unlike the traditional analysis where the method of steepest descent is used, the tunneling coordinate is treated as a quasi-zero mode. This feature allows including the influence of backscattering in the acceptor well and leads to the recovery of the Marcus formula for the rate of electron transfer. The results have implications on the performance of ring polymer molecular dynamics for the study of electron transfer dynamics.
On the stability of fractal globules
Authors: Schram Raoul D. , Barkema Gerard T. , Schiessel Helmut
Published: June 2013

The fractal globule, a self-similar compact polymer conformation where the chain is spatially segregated on all length scales, has been proposed to result from a sudden polymer collapse. This state has gained renewed interest as one of the prime candidates for the non-entangled states of DNA molecules inside cell nuclei. Here, we present Monte Carlo simulations of collapsing polymers. We find through studying polymers of lengths between 500 and 8000 that a chain collapses into a globule, which is neither fractal, nor as entangled as an equilibrium globule. To demonstrate that the non-fractalness of the conformation is not just the result of the collapse dynamics, we study in addition the dynamics of polymers that start from fractal globule configurations. Also in this case the chain moves quickly to the weakly entangled globule where the polymer is well mixed. After a much longer time the chain entangles reach its equilibrium conformation, the molten globule. We find that the fractal globule is a highly unstable conformation that only exists in the presence of extra constraints such as cross-links.
Born-Oppenheimer molecular dynamics and electronic properties of chlorophyll-c2 in liquid methanol
Authors: Cabral Benedito J. C. , Coutinho Kaline , Canuto Sylvio
Published: June 2013

First principles Born-Oppenheimer molecular dynamics of chlorophyll-c2 (chlc2) in liquid methanol is reported. The structure of the chromophore-methanol solution is characterized by non-symmetric solvation and by the displacement of a pentacoordinated Mg atom from the π macrocycle plane of chlc2. Non-symmetrical solvation is in keeping with experimental data reported for chlorophyll-a and bacteriochlorophyll-a indicating a preferential side of the π macrocycle for binding a fifth ligand. The average displacement of the Mg atom (0.38 Å) is similar to X-ray data on magnesium phthalocyanine (∼0.45 Å) and ethyl chlorophyllide-a dihydrate crystals (0.39 Å). The displacement of Mg from the macrocycle plane influences the orientational order of the methanol molecules in the axial region and the results indicate that the face defined by the methoxycarbonyl moiety exhibits a solvatophobic behavior. The maximum of the Soret (B) band for chlc2 in liquid methanol (464 nm) is in good agreement with the experimental value (451 nm) and it is also very close to a recent result for chlc2 in liquid 2-methyl tetrahydrofuran (466 nm). Intramolecular hydrogen bonding involving the carboxyl and methoxycarbonyl moieties of chlc2 leads to a blueshift of ∼20 nm of the B band maximum.
Diffusion of aromatic compounds in nonaqueous solvents: A study of solute, solvent, and temperature dependences
Authors: Chan T. C. , Tang W. K.
Published: June 2013

Tracer diffusivities (limiting mutual diffusion coefficients) of nonassociated aromatic compounds in n-hexane and cyclohexane have been measured at 298.2 K by Taylor's dispersion method. These new data, together with other diffusivities of nonassociated pseudoplanar solutes reported in the literature, are used to determine the separate effects of solute and solvent on tracer diffusion. The data show that for a given pseudoplanar solute diffusing in different solvents at 298.2 K, the tracer diffusivity is dependent not only on the fractional viscosity of the solvent but also on a function of the solvent's molar density, molecular mass, and free volume fraction. For different pseudoplanar aromatic solutes diffusing in a particular solvent at a constant temperature, there is a linear relationship between the reciprocal of the tracer diffusivity and the molecular volume of the solutes. The results are discussed in respect to relevant theories and experimental studies in the literature. An idealized relation, developed on the basis of the Einstein equation by incorporating the newly found solute and solvent dependences, is capable of describing a total of 176 diffusivities of nonassociated pseudoplanar solutes in various solvents at different temperatures to within an average error of ±2.8%.
Interpolation of multi-sheeted multi-dimensional potential-energy surfaces via a linear optimization procedure
Authors: Opalka Daniel , Domcke Wolfgang
Published: June 2013

Significant progress has been achieved in recent years with the development of high-dimensional permutationally invariant analytic Born-Oppenheimer potential-energy surfaces, making use of polynomial invariant theory. In this work, we have developed a generalization of this approach which is suitable for the construction of multi-sheeted multi-dimensional potential-energy surfaces exhibiting seams of conical intersections. The method avoids the nonlinear optimization problem which is encountered in the construction of multi-sheeted diabatic potential-energy surfaces from ab initio electronic-structure data. The key of the method is the expansion of the coefficients of the characteristic polynomial in polynomials which are invariant with respect to the point group of the molecule or the permutation group of like atoms. The multi-sheeted adiabatic potential-energy surface is obtained from the Frobenius companion matrix which contains the fitted coefficients. A three-sheeted nine-dimensional adiabatic potential-energy surface of the 2T2 electronic ground state of the methane cation has been constructed as an example of the application of this method.
Simulated annealing–simplex hybrid algorithm for ellipsometric data inversion of multilayer films
Authors: Fan Longfeng , Huang Zuohua
Published: June 2013

A simulated annealing–simplex hybrid algorithm that accurately measures the optical parameters of multilayer films is proposed for ellipsometric data inversion of multilayer films. In single-wavelength ellipsometry experiments, multiple groups of ellipsometric parameters measured by multiple incident angles can determine multiple optical parameters. Analysis of the measurement accuracy of multilayer films indicates that probabilities of uncertainty increase as films become thinner. Accurate measurements show that using the hybrid algorithm to obtain the optical parameters of multilayer films is feasible and reliable. The algorithm can be used for the inversion and the actual measurement of double-layer and multilayer films by single-wavelength ellipsometry.
Effects of extraneous surface charges on the enhanced Raman scattering from metallic nanoparticles
Authors: Chung H. Y. , Leung P. T. , Tsai D. P.
Published: June 2013

Motivating by recent experiments on surface enhanced Raman scattering (SERS) from colloidal solutions, we present here a simple model to elucidate the effects of extraneous surface charges on the enhanced Raman signal. The model is based on the well-established Gersten-Nitzan model coupled to the modified Mie scattering theory of Bohren and Hunt in the long wavelength approximation. We further introduce corrections from the modified long wavelength approximation to the Gersten-Nitzan model for the improvement of its accuracy. Our results show that the surface charge will generally lead to a blueshift in the resonance frequency and greater enhancements in the SERS spectrum. Possible correlations with the recent experiments are elaborated.
Hydroxylation induced stabilization of near-surface rocksalt nanostructure on wurtzite ZnO structure
Authors: Pandey Mohnish , Pala Raj Ganesh S.
Published: June 2013

We present a density functional study of the structural behavior of zinc oxide nanostructures in basic growth condition which consequently leads to the formation of few layers of hydroxylated rocksalt structure over the wurtzite ZnO structure. We demonstrate the greater stability of the few layers of hydroxylated zinc oxide polar surface in rocksalt structure as compared to wurtzite structure. This coerces the near-surface layers of the nanostructure to acquire rocksalt structure giving rise to a trilayer structure consisting of a layer of hydroxyls on ZnO surface, rocksalt near-surface layers, and wurtzite bulk(or wurtzite sub-surface). The formation of coherent interface between rocksalt and wurtzite structure forces the hydroxylated trilayer structure to have lattice constant in between that of a rocksalt and wurtzite structure. Further, the hydroxylated rocksalt structure in the trilayer configuration is stable up to a critical size of the trilayer above which the increasing strain due to lattice mismatch between rocksalt and wurtzite structure overcomes the stabilizing effect of the hydroxylated rocksalt structure.
Virtual GaN substrates via Sc2O3/Y2O3 buffers on Si(111): Transmission electron microscopy characterization of growth defects
Authors: Niermann T. , Zengler D. , Tarnawska L. , Stork P. , Schroeder T. , Lehmann M.
Published: June 2013

The defects and strain of GaN(0001) films as virtual substrate on Si(111) with step-graded Sc2O3(111)/Y2O3(111) buffers were investigated by means of transmission electron microscopy. The misfit dislocation network identified in the interfaces nearly fully compensates the lattice mismatch. Inversion domains and pinholes occur within the closed GaN film. The atomic structure of the inversion domain boundaries is identified. Major parts of the films were found to be N-polar. Threading dislocations were formed as remains from the coalescence of initial GaN islands. Furthermore, the formation of small cubic inclusions is found to be restricted to the vicinity of the interface only.
Microscale electrostatic fractional capacitors using reduced graphene oxide percolated polymer composites
Authors: Elshurafa A. M. , Almadhoun Mahmoud N. , Salama K. N. , Alshareef H. N.
Published: June 2013

We show that graphene-percolated polymer composites exhibit fractional capacitance response in the frequency range of 50 kHz–2 MHz. In addition, it is shown that by varying the loading of graphene within the matrix from 2.5% to 12%, the phase can be controllably tuned from −67° to −31°, respectively. The electrostatic fractional capacitors proposed herein are easy to fabricate and offer integration capability on electronic printed circuit boards.
Enhanced fatigue and ferroelectric properties in multiferroic (Ba0.7Sr0.3)TiO3/(Bi1.05La0.05)FeO3 epitaxial heterostructures
Authors: Miao Jun , Chew K.-H. , Zhang J. X. , Zhan Q. , Xu X. G. , Jiang Y.
Published: June 2013

Fatigue and ferroelectric properties of multiferroic (Ba0.7Sr0.3)TiO3/(Bi1.05La0.05)FeO3 (BST/BLF) epitaxial heterostructures are studied and compared to those of BLF single-layer films. Our studies show that oxygen vacancies VO•• are the most likely mobile defects in bilayers, whereas defect dipole complexes (FeFe3+′−VO••) dominate the single-layer film. However, the fatigue mechanism in both structures is mainly governed by the migration of VO••. The presence of BST layer in the bilayer increases the energy barrier for the migration of VO•• and decreases the concentration of VO••. The BST/BLF bilayer reveals an improved fatigue and ferroelectric properties, suggesting a step towards realizing nonvolatile memory applications.
Iron related donor-like defect in zinc oxide
Authors: Quemener V. , Vines L. , Monakhov E. V. , Svensson B. G.
Published: June 2013

Hydrothermally grown ZnO samples, annealed in Zn-rich and O-rich ambients, have been investigated by deep level transient spectroscopy. A clear correlation has been found between the annealing treatment and the formation/suppression of two defect levels at ∼0.19 (E2) and ∼0.54 (E4) eV below the conduction band edge (Ec). Moreover, a close proportionality over more than three orders of magnitude has been established between the concentration of E2 and that of Fe, as determined by secondary ion mass spectrometry. Based on the above observations and previous reports in the literature, Fe on Zn-site is a likely candidate for E2.
Study of conduction and switching mechanisms in Al/AlOx/WOx/W resistive switching memory for multilevel applications
Authors: Zhang Ye , Wu Huaqiang , Bai Yue , Chen An , Yu Zhiping , Zhang Jinyu , Qian He
Published: June 2013

In this letter, the conduction and switching mechanisms of Al/AlOx/WOx/W bilayer resistive random access memory devices are investigated. Five stable resistance states were achieved through current compliance control. For each resistance state, I-V characteristics at different temperatures were measured. Conduction mechanisms are found to vary with resistance states. At low resistance levels, devices show ohmic conduction with metallic behavior. Conduction at medium resistance levels is due to electron hopping. The carrier transport at high resistance levels is governed by Schottky emission. Based on the resistance-dependent transport characteristics, an oxygen migration model is proposed to explain the switching mechanism between different resistance states.
Characterization of heat loads from mitigated and unmitigated vertical displacement events in DIII-D
Authors: Hollmann E. M. , Commaux N. , Eidietis N. W. , Humphreys D. A. , Jernigan T. J. , Lasnier C. J. , Moyer R. A. , Pitts R. A. , Sugihara M. , Strait E. J. , Watkins J. , Wesley J. C.
Published: June 2013

Experiments have been conducted on the DIII-D tokamak to study the distribution and repeatability of heat loads and vessel currents resulting from vertical displacement events (VDEs). For unmitigated VDEs, the radiated power fraction appears to be of order 50%, with the remaining power dominantly conducted to the vessel walls. Shot-to-shot scatter in heat loads measured at one toroidal location is not large (<±50%), suggesting that toroidal asymmetries in conducted heat loads are not large. Conducted heat loads are clearly observed during the current quench (CQ) of both mitigated and unmitigated disruptions. Significant poloidal asymmetries in heat loads and radiated power are often observed in the experiments but are not yet understood. Energy dissipated resistively in the conducting walls during the CQ appears to be small (<5%). The mitigating effect of neon massive gas injection (MGI) as a function of MGI trigger delay has also been studied. Improved mitigation is observed as the MGI trigger delay is decreased. For sufficiently early MGI mitigation, close to 100% radiated energy and a reduction of roughly a factor 2 in vessel forces is achieved.
Photoconductivity of amorphous As2S8 chalcogenide film under bandgap light irradiation
Authors: Zou L. E. , Ge Y. D. , Shen Y. , Chen B. X. , Iso M.
Published: June 2013

The photoconductivity of amorphous As2S8 chalcogenide film under the irradiation of bandgap light is investigated. In the temperature range 300–350 K, the dark conductivity and photoconductivity of the annealed As2S8 film increase with the temperature, and the dependence of the both on temperature shows that the conduction in As2S8 film is an activated process having single activation energy. Under the irradiation of bandgap light, the photocurrents of the annealed and illuminated As2S8 film increase with the irradiation intensity, and their difference indicates the existence of the light-soaked effect. Meanwhile, the photoconductivity degradation during the irradiation and the photocurrent decay after stopping the irradiation are observed. By adding the irradiation of the sub-bandgap light, the enhancement of photoinduced voltage occurs.
High-resolution photocurrent microscopy using near-field cathodoluminescence of quantum dots
Authors: Yoon Heayoung P. , Lee Youngmin , Bohn Christopher D. , Ko Seung-Hyeon , Gianfrancesco Anthony G. , Steckel Jonathan S. , Coe-Sullivan Seth , Talin A. Alec , Zhitenev Nikolai B.
Published: June 2013

We report a fast, versatile photocurrent imaging technique to visualize the local photo response of solar energy devices and optoelectronics using near-field cathodoluminescence (CL) from a homogeneous quantum dot layer. This approach is quantitatively compared with direct measurements of high-resolution Electron Beam Induced Current (EBIC) using a thin film solar cell (n-CdS / p-CdTe). Qualitatively, the observed image contrast is similar, showing strong enhancement of the carrier collection efficiency at the p-n junction and near the grain boundaries. The spatial resolution of the new technique, termed Q-EBIC (EBIC using quantum dots), is determined by the absorption depth of photons. The results demonstrate a new method for high-resolution, sub-wavelength photocurrent imaging measurement relevant for a wide range of applications.
Influence of Survey Design on Fish Assemblages: Implications from a Study in Chesapeake Bay Tributaries
Authors: Tuckey Troy D. , Fabrizio Mary C.
Published: June 2013

Aquatic resource surveys that span multiple decades provide valuable information about fish population responses to environmental and human‐induced changes. Often, surveys are altered as scientific objectives change or in response to management needs. These modifications usually result in inconsistencies in the time series, which must be addressed for proper analysis of fish community data. Since 1997, juvenile fishes in Virginia tributaries of Chesapeake Bay have been captured monthly using a bottom trawl at both fixed and random sites. Previous surveys in these tributaries (1955–1996) were conducted at fixed sites only; thus, an understanding of the effect of this design change would allow us to infer fish community status through multiple decades. We compared samples from the fixed site design with those from the stratified random design in the James, York, and Rappahannock rivers and examined species composition, biodiversity, relative abundance estimates, and size distributions to understand the effects of survey design on these metrics. Catches from random sites were characterized by consistently higher species richness than those from fixed sites; biodiversity metrics varied by sampling site type (fixed versus random) and river. For most select species, we observed similar trends in relative abundance regardless of site type; however, for some species we noted differences in magnitude among years and between sampling site types. Community metrics, such as taxonomic diversity and distinctness, revealed subtle differences about fish species assemblages compared with traditional diversity metrics demonstrating that community metrics can characterize biodiversity of fishes at higher taxonomic levels. Thus, species‐specific and community metrics derived from assemblage data from fixed‐site surveys may not fully represent the magnitude of change in demersal fish assemblages, but can provide reliable indicators of patterns of change in abundance through time.
Within‐Day Variability in Catch Taken by Public Access Fishers during a Recreational Fishing Survey
Authors: Ashford Julian R. , Jones Cynthia M. , Fegley Lynn
Published: June 2013

Access point surveys of recreational fisheries are usually stratified into weekdays and weekend days and allocate only a single sampling assignment per day sampled; this is because most variation is thought to be due to differences in angler behavior between the week and weekend and between days. However, few estimates of within‐day variability are available, and this source of error has not been adequately assessed. During a 2011 survey of the recreational fishery for blue crabs Callinectes sapidus in Maryland, we used a stratified two‐stage design with week and weekend strata, and multiple assignments were selected randomly within sampling days to measure within‐day variability. Within‐day variability accounted for 85.3–98.5% of the variation in blue crab catch between July and September, whereas 1.5–14.7% of the variation was due to between‐day variability; during the months examined, there was no significant effect due to week–weekend. These results suggest the use of a simple two‐stage design to estimate the recreational catch of blue crabs, with sampling effort allocated to capturing within‐day variability. Better management of the main sources of error can increase the precision and accuracy of catch estimates, and we recommend that recreational surveys use pilot studies to evaluate sources of variation before the study design is finalized.
Psychologists' perspectives on the diagnostic classification of mental disorders: Results from the WHO‐IUPsyS Global Survey
Authors: Evans Spencer C. , Reed Geoffrey M. , Roberts Michael C. , Esparza Patricia , Watts Ann D. , Correia João Mendonça , Ritchie Pierre , Maj Mario , Saxena Shekhar
Published: June 2013

This study examined psychologists' views and practices regarding diagnostic classification systems for mental and behavioral disorders so as to inform the development of the ICD‐11 by the World Health Organization (WHO). WHO and the International Union of Psychological Science (IUPsyS) conducted a multilingual survey of 2155 psychologists from 23 countries, recruited through their national psychological associations. Sixty percent of global psychologists routinely used a formal classification system, with ICD‐10 used most frequently by 51% and DSM‐IV by 44%. Psychologists viewed informing treatment decisions and facilitating communication as the most important purposes of classification, and preferred flexible diagnostic guidelines to strict criteria. Clinicians favorably evaluated most diagnostic categories, but identified a number of problematic diagnoses. Substantial percentages reported problems with crosscultural applicability and cultural bias, especially among psychologists outside the USA and Europe. Findings underscore the priority of clinical utility and professional and cultural differences in international psychology. Implications for ICD‐11 development and dissemination are discussed.