bluuebunny/crossref_metadata_2025 huggingface dataset:
Disintegration, recognition, and violence: A theoretical perspective
Authors: Heitmeyer Wilhelm , Anhut Reimund
Published: October 2008

The literature explaining deviance, criminality, or violence offers a broad spectrum of approaches in criminology and sociology. Mostly the theories focus on specific levels of explanation like the macrolevel (for example, strain theories) or the microlevel (for example, self‐control theory).

This article presents a relatively new theoretical approach combining different levels and focusing on three dimensions associated with specific kinds of recognition: social‐structural, institutional, and socioemotional. The social‐structural dimension refers to access to the functional systems of society and the accompanying recognition of position, status, and so on. The institutional dimension concentrates on the opportunity to participate in public affairs with the aim of getting moral recognition. The socioemotional dimension emphasizes the quantity and quality of integration in and social support from families, friends, partners, and so on, which provide emotional recognition.

The underlying idea is that lack of access, participation, and belonging causes a lack of recognition. When this happens, social and individual problems increase. Thus, deviant and violent behavior can be seen as one potential reaction to a lack of recognition and as a way to gain status and recognition in a different manner (for example, with a delinquent peer group or other gang).
Violence in street culture: Cross‐cultural comparison of youth groups and criminal gangs
Authors: Zdun Steffen
Published: October 2008

Violence is a widespread phenomenon in juvenile street culture. But the questions of whether this relationship is a deterministic one, and if not, which are the contributing factors, are largely unanswered. This article focuses on the role of public space, starting with a comparison of the meaning of deviant behavior and crime in street culture in Brazil, Russia, and Germany. Focusing on street culture norms and their relevance for youth groups in everyday life, the author shows that there are worldwide similarities, and these are most likely to be seen in disadvantaged neighborhoods. The article deals not only with the question of how people act in conflicts but also focuses on a social order in which the reputation of men is based mainly on questions of masculinity, honor, and power expressed through aggressive behavior. The results are based on more than one hundred semistructured qualitative interviews with street culture youth, prison inmates, adult family members, social workers, police, and researchers that were conducted in recent years in the three countries.

The study also describes a typology of conflict behavior among male street culture youth that helps in understanding why even juveniles who were socialized in the milieu of the street culture can reject violence and do not have to turn to violence in all conflicts. The article examines the similarities in the reasons for violence and fear of violence, as well as the differences in frequency and intensity between violent countries (such as Brazil and the Russian Federation) and less violent countries (for example, Germany).
Fears of violence among English young people: Disintegration theory and British social policy
Authors: Cockburn Tom
Published: October 2008

Young people are not only the perpetrators of violence; they are also the victims of violent acts. This leads to the question of how young people handle potential risk and how they can reduce the danger of becoming victims. The article stresses the topic of juvenile experience and fear of violence. Starting with a description of the nature of social disintegration in the north of England and the social consequences of social change at the beginning of the twenty‐first century, the author focuses on the experience of young people who are affected by changes in social policies, such as the governmental response to antisocial behavior, which is generally considered to be the cause of escalating youth crime. It is pointed out that young people's experience of social disintegration is more complex than generally considered. Based on one of the few qualitative studies in this research field, the study outlines the reasons for fear of violence by presenting comments by young people in two cities and three smaller towns in the north of England. In particular, it looks at the experience of young people in public spaces, the effect of excessive alcohol consumption, young people's fears around illegal drugs and violence, strategies young people use to remain safe, and factors that tend to reduce perceived safety. The authors question the wider societal view that young people are passive and innocent objects: this view has consequences regarding the drive to reduce and avoid violence (by adult society) but also can result in increased insecurity for young people. For this reason, the article also provides a new political approach regarding the communal context.
The role of social work in the context of social disintegration and violence
Authors: Möller Kurt
Published: October 2008

Violence and the violence discourse are very similar from country to country: focus on youth, preponderance of males among perpetrators and victims, disproportionate involvement of migrants and indigenous people, greater prevalence with socioeconomic disadvantage and low education, and the impact of underlying factors such as political disintegration, exclusion from the consumer lifestyle, and inadequacies of social institutions. In social disintegration theory, the basic explanatory backdrop is the dynamic relationship of integration and disintegration between and within the different spheres: individual and functional system integration, integration into society, and integration into the community. (Relative) exclusion from work, consumption, and democratic processes combined with experience of socioemotional deficits seem to give a particularly strong boost to socially unacceptable forms of particularist integration and to favor collective and individual acceptance of violence. When subjects draw balances of personal recognition and of the achieved and achievable scope to organize their life, the latter orientations appear subjectively more likely to meet their expectations than socially (more) accepted modes of behavior.

The central conclusion on social reactions to violence in general and professional social work in particular is that rather than relying on admonishment, punishment, or curative measures, or some combination of these, to combat violence, there is a need for wide‐ranging long‐term options for those acutely affected and at risk to have the long‐term scope to organize their own lives—to experience life control, recognized integration, and development of competences. Those who experience being the organizer of their own life have no need of violence as a form of self‐assertion.
Sensory‐motor polyneuropathy occurring in variant maple syrup urine disease
Authors: Harty S. , King M. D. , McCoy B. , Costigan D. , Treacy E. P.
Published: October 2008

Maple syrup urine disease (MSUD; OMIM 248600) results from an inherited deficiency of the branched‐chain ketoacid dehydrogenase (BCKD) complex. Approximately 20% of patients with BCKD deficiency are non‐classic variants of MSUD with differing clinical severity. Outcomes for this cohort are generally favourable; episodes of metabolic decompensation do not appear to correlate with adverse events if acute management is promptly provided. A case of predominantly axonal sensory‐motor neuropathy following metabolic decompensation which persisted for a number of months is presented in an adolescent girl with variant (intermediate type) MSUD. EMG and nerve conduction studies suggested a pre‐existent asymptomatic chronic neuropathy, exacerbated by the acute decompensation. Peak leucine concentration at decompensation was 1083 μmol/L. The patient had laboratory signs of secondary mitochondrial respiratory chain dysfunction at presentation. She had been on a moderate dose of thiamine prior to decompensation; thiamine and pyridoxine blood concentrations were normal. This, to our knowledge, is the first report of a neuropathy presenting in a patient with a decompensation of variant MSUD. We propose that this presentation resembles the intermittent neuropathy observed in pyruvate dehydrogenase deficiency and may reflect secondary inhibition of pyruvate dehydrogenase activity by MSUD metabolites.
Detection of treatable neonatal liver disease by expanded newborn screening
Authors: Mackay R. J. , Bratkovic D. , Couper R. , Davidson G. P. , Fahy R. , Fletcher J. M. , Ranieri E.
Published: October 2008

Two neonates were identified at age 48 h by expanded newborn screening, with abnormal methionine and tyrosine concentrations, which were confirmed on repeat samples. Evidence of previously unsuspected liver disease was found at recall, and there was radiological and biochemical evidence of severe liver disease with hepatic synthetic failure. After inborn errors of metabolism (IEMs) were excluded, both were considered to have neonatal haemochromatosis, on the basis of raised ferritin, iron saturation, and very high α‐fetoprotein and confirmed by a mildly hyperferritinaemic sibling in the first case, and raised ferritin and iron saturation in the second. However, it was not feasible to obtain tissue confirmation as the requirement for early therapy precluded biopsy. The babies were treated with antioxidants and iron‐chelating agents, and the coagulopathy and hypoalbuminaemia were corrected. Both made a complete recovery and remain well after follow‐up. Newborn screening programmes could consider advising clinicians, when tyrosine and methionine values are elevated, that once IEMs are excluded liver disease from other causes must be sought. Neonatal haemochromatosis is an example of one such disease that is potentially treatable.
Selbstmanagement im Arbeits- und Berufsleben
Authors: Wiese Bettina S.
Published: October 2008

Zusammenfassung. Es wird eine Übersicht zu personalpsychologisch relevanten Selbstmanagementansätzen gegeben, die sich sowohl auf das unmittelbare Arbeitshandeln als auch auf das berufsbiografisch relevante Handeln beziehen. Dabei wird auf Ansätze aus verschiedenen Subdisziplinen der Psychologie Bezug genommen und deren Anwendbarkeit auf selbstgesteuertes arbeits- und berufsbezogenes Handeln geprüft. Im Vordergrund stehen Fragen der Zielsetzung und der zur Zielerreichung benötigten Handlungsstrategien (inkl. volitionaler Steuerungskompetenzen). Außerdem wird auf die Förderbarkeit von Selbstmanagementkompetenzen eingegangen. Schließlich wird gezeigt, warum es insbesondere aus berufsbiografischer Sicht sinnvoll sein kann, einen umfassenderen Blick auf Fragen des Selbstmanagements zu werfen und dabei auch Ziele und Wünsche in anderen Lebensbereichen mit einzubeziehen. Zentrale Zielsetzung des Beitrags ist es, einen thematischen Überblick zu geben und die Potenziale, aber auch Grenzen einzelner Ansätze zu diskutieren.
HR Practices and Workforce Prospects
Authors: Claes Rita
Published: October 2008

Abstract. The study explored the workforce reduction/expansion – as anticipated by HR managers – in relation with humanresource practices (HRPs), while taking into account organisational characteristics. Provided HRPs were reported by HR managers (N = 86) and by their employees (N = 1830). The research in six European countries (i. e., Belgium, Germany, the Netherlands, Spain, Sweden, and the UK) introduced ”country” as a variable for the HRPs-performance relationship. The one-to-one relationships of organisational characteristics and HRPs with workforce reduction/expansion were analysed with χ2-tests. The main findings were: (1) Societal contexts, size of the organisation, and past workforce fluctuations are important when HR managers anticipate workforce prospects, and 2) HRPs relate differently to workforce prospects, depending on the source reporting on provided HRPs (HR managers versus their employees).
Dependence of the Omori‐Utsu law parameters on main shock magnitude: Observations and modeling
Authors: Hainzl S. , Marsan D.
Published: October 2008

We examine the dependence on main shock magnitudemof thepandχparameters appearing in Omori‐Utsu formulaλ(t,m) =χ× (t+c)−prelating the rate of aftershocksλat timetafter a main shock. Observations point out to a significant increase ofpwithm, along with a scaling relationship of the formχ∼ 10αm. Here we show that these observations can be explained within the framework of the rate‐and‐state friction model when accounting for realistic levels of coseismic stress heterogeneity on the main fault. We constrain the model parameters in order to recover the trends observed in previous and new analyses of aftershock sequences. The expected ratio of the coseismic stress drop standard deviation to its mean is found to be of the order of a few units for large (m= 7) earthquakes, resulting in a very rough stress field at the small scale, while it is much smoother at small magnitudes (ratio ≃ 0.1 atm= 2). Finally, the influence of afterslip on parameterspandχis studied to highlight the fact that it can significantly perturb thep(m) andχ(m) relations obtained with the initial afterslip‐free model.
Ocean biogeochemical response to phytoplankton‐light feedback in a global model
Authors: Manizza Manfredi , Le Quéré Corinne , Watson Andrew J. , Buitenhuis Erik T.
Published: October 2008

Oceanic phytoplankton, absorbing solar radiation, can influence the bio‐optical properties of seawater and hence upper ocean physics. We include this process in a global ocean general circulation model (OGCM) coupled to a dynamic green ocean model (DGOM) based on multiple plankton functional types (PFT). We not only study the impact of this process on ocean physics but we also explore the biogeochemical response due to this biophysical feedback. The phytoplankton‐light feedback (PLF) impacts the dynamics of the upper tropical and subtropical oceans. The change in circulation enhances both the vertical supply in the tropics and the lateral supply of nutrients from the tropics to the subtropics boosting the subtropical productivity by up to 60 gC m−2 a−1. Physical changes, due to the PLF, impact on light and nutrient availability causing shifts in the ocean ecosystems. In the extratropics, increased stratification favors calcifiers (by up to ∼8%) at the expense of mixed phytoplankton. In the Southern Ocean, silicifiers increase their biomass (by up to ∼10%) because of the combined alleviation of iron and light limitation. The PLF has a small effect globally on air‐sea fluxes of carbon dioxide (CO2, 72 TmolC a−1 outgassing) and oxygen (O2, 46 TmolO2 a−1 ingassing) because changes in biogeochemical processes (primary production, biogenic calcification, and export production) highly vary regionally and can also oppose each other. From our study it emerges that the main impact of the PLF is an amplification of the seasonal cycle of physical and biogeochemical properties of the high‐latitude oceans mostly driven by the amplification of the SST seasonal cycle.
Phoenix Robotic Arm Camera
Authors: Keller H. U. , Goetz W. , Hartwig H. , Hviid S. F. , Kramm R. , Markiewicz W. J. , Reynolds R. , Shinohara C. , Smith P. , Tanner R. , Woida P. , Woida R. , Bos B. J. , Lemmon M. T.
Published: October 2008

The Phoenix Robotic Arm Camera (RAC) is a variable‐focus color camera mounted to the Robotic Arm (RA) of the Phoenix Mars Lander. It is designed to acquire both close‐up images of the Martian surface and microscopic images (down to a scale of 23 μm/pixel) of material collected in the RA scoop. The mounting position at the end of the Robotic Arm allows the RAC to be actively positioned for imaging of targets not easily seen by the Stereo Surface Imager (SSI), such as excavated trench walls and targets under the Lander structure. Color information is acquired by illuminating the target with red, green, and blue light‐emitting diodes. Digital terrain models (DTM) can be generated from RAC images acquired from different view points. This can provide high‐resolution stereo information about fine details of the trench walls. The large stereo baseline possible with the arm can also provide a far‐field DTM. The primary science objectives of the RAC are the search for subsurface soil/ice layering at the landing site and the characterization of scoop samples prior to delivery to other instruments on board Phoenix. The RAC shall also provide low‐resolution panoramas in support of SSI activities and acquire images of the Lander deck for instrument and Lander check out. The camera design was inherited from the unsuccessful Mars Polar Lander mission (1999) and further developed for the (canceled) Mars Surveyor 2001 Lander (MSL01). Extensive testing and partial recalibration qualified the MSL01 RAC flight model for integration into the Phoenix science payload.
Seasonal and interannual litter dynamics of a tropical semideciduous forest of the southern Amazon Basin, Brazil
Authors: Sanches Luciana , Valentini Carla Maria Abido , Júnior Osvaldo Borges Pinto , de Souza Nogueira José , Vourlitis George Louis , Biudes Marcelo Sacardi , da Silva Carlos José , Bambi Paulino , de Almeida Lobo Francisco
Published: October 2008

This study analyzed how seasonal and interannual variations in climate alter litter dynamics, including production, decomposition, and accumulation. Monthly measurements of leaf, stem, and reproductive (flower plus fruit) litter and the forest floor litter mass were combined with a mass balance model to determine rates of litter decomposition for a semideciduous tropical forest located in the rain forest‐savanna ecotone of the southern Amazon Basin for 2001–2007. Annual rates of litter production varied between 8 and 10.5 Mg ha−1 a−1, and leaf litter production accounted for the majority (∼70%) of the total litter production. Leaf litter production peaked at the end of the May–August dry season while stem litter production peaked during the wet season and reproductive litter production peaked during the dry‐wet season transition. Forest floor litter mass ranged between 5 and 8 Mg ha−1 over the study period and generally declined as litter inputs declined. Litter decomposition rates were remarkably stable from year‐to‐year and varied between 10.8 and 12.4 Mg ha−1 a−1. On average, rates of litter decomposition were highest during the dry‐wet season transition. Overall, our results suggest that rainfall variability directly altered litter production dynamics and indirectly altered forest floor litter mass and decomposition kinetics through its effect on litter production. Future changes in seasonal and/or interannual rainfall patterns, whether in response to El Niño or to anthropogenic climate change, will likely have important consequences for the litter dynamics of Amazonian semideciduous forest.
Mesoscale Dynamics
Authors: Orlanski Isidro
Published: October 2008

Mesoscale meteorology is the study of atmospheric phenomena with typical spatial scales between 10 and 1000 kilometers. Examples of mesoscale phenomena include fronts, mesoconvective systems, thunderstorms, gap winds, downslope windstorms, and land‐sea breezes. Many of the weather phenomena that most directly affect human activity occur on the mesoscale.

While researchers have been able to successfully predict large‐scale weather patterns since the 1950s, the prediction of smaller—or mesoscale—phenomena such as storms has proven more difficult. Why the lag in mesoscale prediction? The dynamics of weather phenomena on large scales can largely be described by considering just hydrostatic and geostrophic balance, allowing them to be described by highly simplified models.
Next generation of deformation models for the 2004 M9 Sumatra‐Andaman earthquake
Authors: Masterlark Timothy , Hughes Kristin L. H.
Published: October 2008

The 2004 M9 Sumatra‐Andaman Earthquake (SAE) ruptured the interface separating the subducting Indo‐Australian plate from the overriding Burma plate. We construct finite element models (FEMs) that simulate deformation of the earthquake for a three‐dimensional problem domain partitioned to account for the distribution of material properties of the subducting slab, forearc, volcanic arc, and backarc. We demonstrate a protocol‐based approach for simulating coseismic deformation, in which FEMs are implemented in inverse models to estimate the fault‐slip distribution of the SAE while simultaneously honoring the geologic complexity of the subduction zone. Results suggest that deformation prediction sensitivities attributed to neglecting the different material properties of the subduction zone can be more than an order of magnitude greater than reported uncertainties for near‐field GPS measurements. The FEM‐based techniques presented here allow for geologically satisfying deformation models that will advance the reliability of modeling‐based assessments of coseismic and postseismic deformation, stress‐coupling, and tsunami genesis.
Evidence of baroclinic waves in the upper atmosphere of Mars using the Mars Global Surveyor accelerometer data
Authors: Seth S. P. , Brahmananda Rao V.
Published: October 2008

Here we use accelerometer data of 115 orbits (#P0670–P0789) from 1–30 November 1998, between latitude ranges (50–70°N), and of 57 orbits (#P0588–P0648) from 30 September 1998 to 24 October 1998, between latitude ranges (50–70°N), both under spring equinox and medium solar activity conditions. The neutral densities of different gases are derived from their mixing ratio. From these neutral densities, the longitudinal distribution of total peak ionization rates of CO2+, N2+, O2+, O+, and CO+ are obtained for solar zenith angle 78° because of solar EUV and soft X‐ray (1–102.57 nm) radiation using Analytical Yield Spectrum approach. These calculations are made at different altitudes and longitudes starting from 115 to 220 km and from 0 to 360°E using intervals of 0.1 km and 5°, respectively. These conditions are appropriate for Mars Global Surveyor Phase 2 aerobraking period from which the accelerometer data is used. The Fourier analysis is carried out on the calculated total peak ionization rates for different gases both at midlatitude (17–42°N) and high‐latitude (50–70°N) range in the upper atmosphere of Mars. This analysis at high latitude indicates the presence of two dominant harmonic regions, in which the first is a class of long planetary‐scale waves, associated with the fixed topography of Martian surface, while the second is a class of rapidly moving transient disturbances associated with baroclinic instability processes. The similar analysis carried out at midlatitude (17–42°N) region indicates the absence of second peak at higher wave number, confirming that the baroclinic instability is almost absent at this latitude region.
Solute transport in rivers with multiple storage zones: The STIR model
Authors: Marion A. , Zaramella M. , Bottacin‐Busolin A.
Published: October 2008

Solute transport in rivers is controlled by surface hydrodynamics and by mass exchanges between the surface stream and distinct retention zones. This paper presents a residence time model for stream transport of solutes, Solute Transport in Rivers (STIR), that accounts for the effect of the stream‐subsurface interactions on river mixing. A stochastic approach is used to derive a relation between the in‐stream solute concentration and the residence time distributions (RTDs) in different retention domains. Particular forms of the RTD are suggested for the temporary storage within surface dead zones and for bed form–induced hyporheic exchange. This approach is advantageous for at least two reasons. The first advantage is that exchange parameters can generally be expressed as functions of physical quantities that can be reasonably estimated or directly measured. This gives the model predictive capabilities, and the results can be generalized to conditions different from those directly observed in field experiments. The second reason is that individual exchange processes are represented separately by appropriate residence time distributions, making the model flexible and modular, capable of incorporating the effects of a variety of exchange processes and chemical reactions in a detailed way. The capability of the model is illustrated with an example and with an application to a field case. Analogies and differences with other established models are also discussed.
Role of apoptosis‐regulating signal kinase 1 in innate immune responses by Mycobacterium bovis bacillus Calmette‐Guérin
Authors: Yuk Jae‐Min , Shin Dong‐Min , Yang Chul‐Su , Kim Ki Hye , An Se‐Jin , Rho Jaerang , Park Jeong‐Kyu , Jo Eun‐Kyeong
Published: October 2008

Mycobacterium bovis bacillus Calmette‐Guérin (BCG) induces innate immune responses through Toll‐like receptor (TLR) 2 and TLR4. We investigated the role of apoptosis‐regulating signal kinase (ASK) 1 in reactive oxygen species (ROS)‐mediated innate immune responses induced by BCG mycobacterial infection. In macrophages, M. bovis BCG stimulation resulted in rapid activation of mitogen‐activated protein kinases (MAPKs), secretion of inflammatory cytokines, such as tumor necrosis factor (TNF)‐α and interleukin (IL)‐6, and ROS generation in a TLR2‐ and TLR4‐dependent manner. M. bovis BCG‐induced ROS production led to robust activation of ASK1 upstream of the c‐jun‐N‐terminal kinase and p38 MAPK, but not extracellular‐regulated kinase 1/2. Blocking ASK1 activity markedly attenuated M. bovis BCG‐induced TNF‐α and IL‐6 production by macrophages. Both TLR2 and TLR4 were required for optimal activation of ASK1 in response to M. bovis BCG. Furthermore, we present evidence that TNF receptor‐associated factor (TRAF) 6 activities were essential for ROS‐mediated ASK1 activation by M. bovis BCG. Finally, ASK1 activities were required for effective control of intracellular mycobacterial survival. Thus, the results of this study suggest a novel role of the TLR–ROS–TRAF6–ASK1 axis in the innate immune response to mycobacteria as a signaling intermediate.
Restraining Opportunism in Hotel Management Contracts
Authors: Panvisavas Veerades , Taylor J. Stephen
Published: October 2008

Management contracts are widely used throughout the world as a mechanism for separating the ownership of hotel properties and their management. The research reported here concerns how Thai hotel owners seek to control the international hotel chains where properties are operated under hotel management contracts (HMCs). Adopting agency theory, the research findings reported here suggest that restraints against agent opportunism tend to focus on two key aspects: contractual controls and operational controls. Additionally, the findings also suggest that the outcome control needs to be viewed as a priority for effectively controlling hotel management companies when using HMCs.
The Impact of Employee Behaviour on Customers' Service Quality Perceptions and Overall Satisfaction
Authors: Kattara Hanan Saad , Weheba Dina , El-Said Osman Ahmed
Published: October 2008

The present study is an attempt to investigate the relationship between employees' positive and negative behaviours, customers' perception of service quality and overall customer satisfaction. Results of the current study revealed that all employees' behaviours, either negative or positive, are highly correlated to the customers' overall satisfaction. The study traced the impact of behaviours on customers' perceptions and overall satisfaction through studying the relevant literature and by gauging opinions on the impact of employees' behaviours on customers' perceptions of quality and overall satisfaction. Findings in this context confirmed the correlation between these variables and their consecutive and exchanging effect. It was also concluded that employees' behaviours have great effect on overall customer satisfaction regardless of customers' gender, nationality, and purpose of visit, number of visits and length of stay. Finally, the study ends up by offering suggestions and practical implications for hotel practitioners to think strategically and implement effective tools to motivate employees towards behaving positively with customers.
Atomistic dipole moments and polarizabilities of NaN clusters, N=2–20
Authors: Jackson K. , Ma L. , Yang M. , Jellinek J.
Published: October 2008

The atomic-level response of NaN clusters, N=2–20, to a small static external electric field is studied using a method that decomposes the total cluster dipole moment and polarizability into contributions from nonoverlapping atomic volumes. The atomic dipole moments and polarizabilities are, in turn, partitioned into the so-called dipole and charge-transfer components. The former characterizes a dielectric type of a response, whereas the latter represents a metallic type of a response. Analysis of the atomic polarizabilities points to their strong dependence on the site, or location, of the atoms within the structure of the clusters. Surface atoms have larger polarizabilities than the interior ones. Overall, the fraction of the charge-transfer component of the averaged atomic polarizabilities is an increasing function of the cluster size. The charge-transfer component is also responsible for the structure/shape driven variations in the atomic polarizabilities. The anisotropy of the total polarizabilities correlates with the shape anisotropy of the clusters.
Many-fluid Onsager density functional theories for orientational ordering in mixtures of anisotropic hard-body fluids
Authors: Malijevský Alexandr , Jackson George , Varga Szabolcs
Published: October 2008

The extension of Onsager’s second-virial theory [L. Onsager, Ann. N.Y. Acad. Sci. 51, 627 (1949)] for the orientational ordering of hard rods to mixtures of nonspherical hard bodies with finite length-to-breadth ratios is examined using the decoupling approximations of Parsons [Phys. Rev. A 19, 1225 (1979)] and Lee [J. Chem. Phys. 86, 6567 (1987); 89, 7036 (1988)]. Invariably the extension of the Parsons–Lee (PL) theory to mixtures has in the past involved a van der Waals one-fluid treatment in which the properties of the mixture are approximated by those of a reference one-component hard-sphere fluid with an effective diameter which depends on the composition of the mixture and the molecular parameters of the various components; commonly this is achieved by equating the molecular volumes of the effective hard sphere and of the components in the mixture and is referred to as the PL theory of mixtures. It is well known that a one-fluid treatment is not the most appropriate for the description of the thermodynamic properties of isotropic fluids, and inadequacies are often rectified with a many-fluid (MF) theory. Here, we examine MF theories which are developed from the virial theorem and the virial expansion of the Helmholtz free energy of anisotropic fluid mixtures. The use of the decoupling approximation of the pair distribution function at the level of a multicomponent hard-sphere reference system leads to our MF Parsons (MFP) theory of anisotropic mixtures. Alternatively the mapping of the virial coefficients of the hard-body mixtures onto those of equivalent hard-sphere systems leads to our MF Lee (MFL) theory. The description of the isotropic-nematic phase behavior of binary mixtures of hard Gaussian overlap particles is used to assess the adequacy of the four different theories, namely, the original second-virial theory of Onsager, the usual PL one-fluid theory, and the MF theories based on the Lee (MFL) and Parsons (MFP) approaches. A comparison with the simulation data for the mixtures studied by Zhou et al. [J. Chem. Phys. 120, 1832 (2004)] suggests that the Parsons MF description (MFP) provides the most accurate representation of the properties of the isotropic-nematic ordering transition and density (pressure) dependence of the order parameters.
Asperity contacts at the nanoscale: Comparison of Ru and Au
Authors: Fortini Andrea , Mendelev Mikhail I. , Buldyrev Sergey , Srolovitz David
Published: October 2008

We develop and validate an interatomic potential for ruthenium based on the embedded atom method framework with the Finnis/Sinclair representation. We confirm that the potential yields a stable hcp lattice with reasonable lattice and elastic constants and surface and stacking fault energies. We employ molecular dynamics simulations to bring two surfaces together, one flat and the other with a single asperity. We compare the process of asperity contact formation and breaking in Au and Ru, two materials currently in use in microelectromechanical system switches. While Au is very ductile at 150 and 300 K, Ru shows considerably less plasticity at 300 and 600 K (approximately the same homologous temperature). In Au, the asperity necks down to a single atom thick bridge at separation. While similar necking occurs in Ru at 600 K, it is much more limited than in Au. On the other hand, at 300 K, Ru breaks by a much more brittle process of fracture/decohesion with limited plastic deformation.
Investigation of the skin effect in the bulk of electrical conductors with spin-polarized neutron radiography
Authors: Manke I. , Kardjilov N. , Strobl M. , Hilger A. , Banhart J.
Published: October 2008

The skin effect in the bulk of an electrical conductor, i.e., the displacement of the current density from the inner part to the edges of a conductor, was investigated with spatial resolution using spin-polarized neutron imaging. Different current frequencies from 10 to 1000 Hz were applied to a sample. At each frequency the current distribution was analyzed and the influence of the electrical contacts was investigated. The experimental findings are in qualitative agreement with theoretical predictions and prove the suitability of spin-polarized neutron imaging as a unique tool for investigations of current density distributions in bulk materials in general.
Enhancement of third harmonic generation by a laser-induced plasma
Authors: Hartinger Klaus , Bartels Randy A.
Published: October 2008

We demonstrate more than two orders of magnitude in enhancement of conversion of an ultrafast probe pulse to the third harmonic that is time delayed with respect to a pump pulse. The enhancement is observed in various atomic and molecular gases over a range of pressures.
Buried melting in germanium implanted silicon by millisecond flash lamp annealing
Authors: Voelskow Matthias , Yankov Rossen , Skorupa Wolfgang , Pezoldt Jörg , Kups Thomas
Published: October 2008

Flash lamp annealing in the millisecond range has been used to induce buried melting in silicon. For this purpose high dose high-energy germanium implantation has been employed to lower the melting temperature of silicon in a predetermined depth region. Subsequent flash lamp treatment at high energy densities leads to local melting of the germanium rich layer. The thickness of the molten layer has been found to depend on the irradiation energy density. During the cool-down period, epitaxial crystallization takes place resulting in a largely defect-free layer.
Electronic properties of titanium in boron-doped silicon analyzed by temperature-dependent photoluminescence and injection-dependent photoconductance lifetime spectroscopy
Authors: Roth Thomas , Rüdiger Marc , Warta Wilhelm , Glunz Stefan W.
Published: October 2008

Temperature-dependent lifetime spectroscopy allows for the determination of defect parameters (like ratio of the carrier capture cross sections and energy level) of pointlike defects in silicon. This necessitates reliable measurements of the low-level injection excess carrier lifetime. Photoluminescence-based measurement techniques have been shown to be ideal for this kind of measurements at room temperature, being immune to several measurement artifacts such as minority carrier trapping or depletion region modulation. In this article it will be shown how the effect of photon reabsorption influences the temperature-dependent photoluminescence measurements and how this can be accounted for using a theoretical model based on the generalized Planck equation. An intentionally titanium-contaminated silicon sample is investigated by means of temperature-dependent photoluminescence and injection-dependent photoconductance lifetime spectroscopy. Defect parameters of two independent recombination centers will be presented, which titanium introduces into the silicon band gap. One defect level at EC−0.24 eV agrees very well with a level found via deep-level transient spectroscopy measurements while another level at EC−0.49 eV could be measured for the first time using the advanced lifetime spectroscopic approach presented here.
Tunable liquid microlens actuated by infrared light-responsive hydrogel
Authors: Zeng Xuefeng , Jiang Hongrui
Published: October 2008

We report on liquid-based tunable microlenses actuated by infrared (IR) light. Multiple micropost structures, made of IR light-responsive hydrogel with entrapped gold nanoparticles, are photopatterned around a lens aperture. The volumetric change in the hydrogel, controlled by IR light, regulates the curvature of a liquid-liquid interface forming the microlens at the aperture and its focal length. The focal length of the microlens can be tuned from −17.4mmto+8.0±0.4mm in seconds under IR irradiation. This microlens can be integrated into optical systems, for instance, for fiber endoscopy.
Control of single attosecond pulse generation from the reflection of a synthesized relativistic laser pulse on a solid surface
Authors: Liu Li , Xia Changquan , Liu Jiansheng , Wang Wentao , Cai Yi , Wang Cheng , Li Ruxin , Xu Zhizhan
Published: October 2008

The influence of the carrier-envelope phase (CEP) of the driving laser pulse on the generation of single attosecond (as) pulses from surface harmonics by using the polarization gating technique is investigated in detail. It is found that the modulation depth of the high-order harmonic spectrum depends on the CEP, and a strong single 68as pulse can be generated when the CEP is stable and has the proper value. The physical origin of the influence of the CEP is explained in terms of the oscillating mirror model.
Correlated reduction in micropipe cross sections in SiC growth
Authors: Gutkin M. Yu. , Sheinerman A. G. , Smirnov M. A. , Kohn V. G. , Argunova T. S. , Je J. H. , Jung J. W.
Published: October 2008

We reveal a correlated reduction in the cross sections of two neighboring micropipes (MPs) in the crystal growth of silicon carbide using computer simulation of phase contrast images. The correlated reduction is explained by the exchange of full-core dislocations in a contact-free reaction between two parallel MPs. We develop a theoretical model that describes the energetics of this process.
Transient behaviors of surface plasmon coupling with a light emitter
Authors: Chuang Wen-Hung , Wang Jyh-Yang , Yang C. C. , Kiang Yean-Woei
Published: October 2008

The transient behaviors of dipole couplings with surface plasmons (SPs) on a metal/dielectric grating interface, including surface plasmon polariton (SPP) and localized surface plasmon (LSP), are numerically demonstrated. Such a dipole-SP coupling process can lead to either enhanced dipole emission or effective pumping of a cavity-confining SP mode. Based on the time-resolved responses of a source pulse, it is found that the dipole-SP coupling features can be excited in several femtoseconds with the decay times ranging from 5 to 20 fs. From the significantly different decay times between the LSP and grating-assisted SPP features, one can classify those SP-coupling features into different application categories of efficient emission and SP energy storage.
A monolithic optical sensor based on whispering-gallery modes in polystyrene microspheres
Authors: Lutti Julie , Langbein Wolfgang , Borri Paola
Published: October 2008

We experimentally demonstrate a monolithic sensor based on sharp whispering-gallery optical resonances of polystyrene microspheres in water attached onto an optical coupler via a solid separation layer index matched to water. A Q-factor of 0.9×106 is measured on a microsphere of 44 μm diameter with a 650 nm thick separation layer. As a proof of principle of the sensing capabilities, we measure the response to refractive index changes and infer a shot-noise limited precision of 1×10−8 refractive index units.
Inner wall coated hollow core waveguide sensor based on double substrate surface enhanced Raman scattering
Authors: Shi Chao , Lu Chao , Gu Claire , Tian Lei , Newhouse Rebecca , Chen Shaowei , Zhang Jin Z.
Published: October 2008

A hollow core waveguide with silver nanoparticles coated on the inner wall has been used for molecular detection based on surface enhanced Raman scattering (SERS). With rhodamine 6G as an analyte molecule and two types of silver nanoparticles as double SERS substrates, the inner wall coated hollow core waveguide (IWCHCW) exhibits higher sensitivity than previous sampling methods with only one substrate. The improvement of sensitivity is attributed to the additional enhancement of the electromagnetic field by double substrate “sandwich” structure. The simple architecture and high sensitivity of IWCHCW make it promising for molecular detection in various analytical and sensing applications.
Evaluation of Australian Brassica napus genotypes for resistance to the downy mildew pathogen, Hyaloperonospora parasitica
Authors: Ge X. T. , Li Hua , Han S. , Sivasithamparam K. , Barbetti M. J.
Published: October 2008

Downy mildew, caused by the pathogen Hyaloperonospora parasitica, is a severe disease of oilseed rape (Brassica napus) seedlings in some regions of Australia. Sixty-three cultivars of Australian spring-type oilseed rape were evaluated for their levels of resistance to five isolates of the downy mildew pathogen, using a cotyledon infection test under controlled-environment conditions. A high level of resistance, characterised by the absence of disease symptoms or only the appearance of very sparse sporulation on inoculated cotyledons, was expressed in cvv. Pioneer 45Y77 and Pioneer 46Y78. This is the first study to identify Australian genotypes of oilseed rape highly resistant to H. parasitica. The resistance to H. parasitica identified in this study will not only enable Australian oilseed rape breeders to incorporate resistance to H. parasitica into new cultivars for enhanced resistance to this disease, but will also allow direct deployment of the most highly resistant genotypes identified directly in situations and regions most conducive to the development of severe downy mildew disease.
Black point formation in barley: environmental influences and quantitative trait loci
Authors: Walker K. Ryan , Able Jason A. , Mather Diane E. , Able Amanda J.
Published: October 2008

Black point and kernel discoloration of barley both appear to occur under conditions of high humidity at grain fill. Both of these traits are likely to result from the enzymatic oxidation of phenolic compounds to quinones and the transformation of those oxidation products to brown or black pigments during high humidity. However, even though black point symptoms are quite distinct from other types of kernel discoloration, black point of barley has not previously been the sole focus of environmental studies or quantitative trait locus (QTL) analysis. We have evaluated black point tolerance in doubled haploid progeny of Alexis/Sloop and mapped QTLs on chromosomes 2H and 3H. We have also established that the occurrence of low vapour pressure deficit, high humidity, and low temperatures is associated with the formation of black point in susceptible varieties. These environmental conditions probably create a moist environment during grain development so that the developing grain cannot dry out. Stress or wounding to the embryo caused by this environment might then lead to black point formation. The results of this study will enable the use of comprehensive genetic and biochemical approaches to develop a more detailed understanding of this disorder.
Agricultural drought analyses for temperate Australia using a biophysical pasture model. 2. Relationship between rainfall and the start and end of predicted droughts
Authors: Lodge G. M. , Johnson I. R.
Published: October 2008

This paper reports relationships between predicted soil water content (SWC) on the first day of the month (SWCFOM, mm of water) and previous monthly rainfall for 100 years of daily climate data (1905–2005) at four sites (Albany, Western Australia; Hamilton, Victoria; and Wagga Wagga and Barraba, New South Wales).
Overall, predicted SWCFOM was correlated (P < 0.05) with rainfall in the previous one, two, or three months. However, the proportion of variation in SWCFOM that could be attributed to its regression on previous rainfall was variable and the relationship tended to improve when individual months were examined. At the three winter-rainfall sites (Albany, Hamilton, and Wagga Wagga), there was a reasonably good relationship between the start of a predicted drought and the end of the growing season and also between the end of a predicted drought and the occurrence of break-of-season. However, for the summer-rainfall dominant site at Barraba, rainfall occurrence was less seasonally defined and there was no clear relationship.
While analysis of historical rainfall data for the months in which predicted agricultural droughts started or ended provided some useful insights, it was concluded that it would probably be more instructive to model SWC outcomes for a range of future rainfall scenarios and then examine their likelihood of occurrence using rainfall percentiles.
Organic amendments influence nutrient availability and cotton productivity in irrigated Vertosols
Authors: Ghosh Subhadip , Hulugalle Nilantha , Lockwood Peter , King Kathleen , Kristiansen Paul , Daniel Heiko
Published: October 2008

There is increasing interest in the use of organic amendments in the Australian cotton (Gossypium hirsutum L.) industry because of perceived benefits to soil health and the environment. A 2-year field experiment was conducted at the Australian Cotton Research Institute (ACRI), near Narrabri, NSW, using three locally available organic amendments applied at typical farmers’ rates to irrigated cotton. The amendments used were cattle manure (10 t/ha), composted cotton gin trash (7.5 t/ha), and a commercial liquefied vermicompost (50 L/ha), and their effects on soil quality characteristics were compared with those of control soil where no amendment was added. The soil (0–0.10 m) was sampled on six occasions and analysed for selected chemical and microbiological properties. The physiological characteristics and nutrient uptake of mature cotton plants were also examined.
The organic amendments did not have a significant effect on microbiological properties as measured by microbial biomass and respiration. Of the chemical properties measured, manure-amended plots showed higher nitrate-nitrogen, available phosphorus, and exchangeable potassium (K) concentrations over 2 years. Exchangeable K was 28% higher where cattle manure was applied than in control plots during the active growth stage of cotton in the first year of experiment. Higher nutrient uptake by mature cotton plants and lower nutrient concentration in soil were observed in the second year. Cotton physiological properties and lint yield were not significantly affected by the application of organic amendments. Seasonal parameters had a strong effect. The results suggest that there are few short-term benefits to be gained in terms of soil quality from application of organic amendments to Vertosols at the rates used in these trials.