bluuebunny/crossref_metadata_2025 huggingface dataset:
Total anomalous pulmonary venous connection: impact of prenatal diagnosis
Authors: Seale A. N. , Carvalho J. S. , Gardiner H. M. , Mellander M. , Roughton M. , Simpson J. , Tometzki A. , Uzun O. , Webber S. A. , Daubeney P. E. F. ,   on behalf of the British Congenital Cardiac Association
Published: January 2012

Objectives

To investigate whether prenatal screening is effective in the detection of total anomalous pulmonary venous connection (TAPVC) and to identify common prenatal features.

Methods

This was a retrospective collaborative study involving 19 pediatric cardiac centers in the UK, Ireland and Sweden. Cases with TAPVC born between January 1, 1998 and December 31, 2004, and prenatally diagnosed cases whose estimated dates of delivery were within this time frame, were identified. Cases with functionally univentricular circulation or atrial isomerism were excluded. All available data and stored images were reviewed.

Results

Four‐hundred and twenty‐four cases with TAPVC were identified prenatally or postnatally, of whom eight (1.9%) had a prenatal diagnosis of TAPVC. Median gestational age at fetal diagnosis was 26 + 6 (range, 22 + 4 to 32 + 0) weeks. Six further fetuses with TAPVC had an abnormality diagnosed on prenatal ultrasound, but not the TAPVC. This included other congenital heart defects (four cases) and isolated pleural effusion (two cases). Seventeen (4.0%) of the 422 liveborn infants had a first‐degree relative with congenital heart disease; and six of 17 had a sibling with TAPVC. Two died in utero. Of the liveborn infants diagnosed prenatally with TAPVC, none required urgent intervention for pulmonary venous obstruction and all were alive and well at a median of 2.3 (range, 1.0–7.0) years after surgical repair.

Conclusion

Prenatal diagnosis of TAPVC is infrequent using current screening methods. Where there is a family history of TAPVC, specialized fetal echocardiography at 20 and 28 weeks' gestation may be indicated. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Psychological Distress with Direct‐to‐Consumer Genetic Testing: A Case Report of an UnexpectedBRCAPositive Test Result
Authors: Dohany Lindsay , Gustafson Shanna , Ducaine Whitney , Zakalik Dana
Published: January 2012

We report a case of a client who discovered she had aBRCAmutation following direct‐to‐consumer (DTC) genetic testing in the absence of genetic counseling. After testing she presented for genetic counseling with anxiety, distress, and a deficit of knowledge about what the DTC genetic testing revealed. Genetic counseling helped alleviate distress while empowering the client to apply the results of testing to improve medical management. Despite recent studies demonstrating no negative psychological impact of DTC genetic testing on the consumer, this case illustrates that significant psychological distress and confusion can occur as a result of DTC genetic testing for highly penetrant single gene disorders. Pre‐ and post‐test genetic counseling in conjunction with DTC genetic testing may alleviate consumers’ distress and empower clients to proactively utilize their result information.
Parent–child relations and psychological adjustment among high‐achieving Chinese and European American adolescents
Authors: Qin Desiree Baolian , Rak Eniko , Rana Meenal , Donnellan M. Brent
Published: January 2012

Chinese American students are often perceived as problem‐free high achievers. Recent research, however, suggests that high‐achieving Chinese American students can experience elevated levels of stress, especially comparing to their peers from other ethnic groups. In this paper, we examine how family dynamics may influence psychological adjustment among a group of high‐achieving adolescents. Drawing on survey data collected on 295 Chinese American and 192 European American 9th graders attending a highly selective magnet school, our findings show that Chinese American adolescents reported significantly lower levels of psychological adjustment (d = −.31), and significantly less family cohesion (d = −.34) and more conflict (d = .56) than their European American peers. Further, the ethnic differences on adjustment disappeared after controlling for perceptions of family cohesion and conflict, indicating that such perceptions may be a key factor in understanding the high academic achievement/low psychological adjustment paradoxical pattern of development among Chinese American adolescents.
Goal engagement and goal attainment in adolescents with and without visual impairment
Authors: Pfeiffer Jens P. , Pinquart Martin
Published: January 2012

The present longitudinal study analyzed the effects of domain‐specific goal engagement on the attainment of four developmental goals in 133 adolescents with visual impairment and in 449 sighted peers. Goal engagement predicted stronger progress in goal attainment with regard to getting access to a peer group, career choice and development of romantic relationships at the 1‐year‐follow‐up. However, goal engagement at T1 did not predict progress in the achievement of autonomy from ones’ parents. Furthermore, we found an interaction effect between vision status and goal engagement on progress in career choice. Higher initial levels of goal engagement predicted stronger progress in goal attainment of sighted adolescents. No such effect was found in adolescents with visual impairment. It is concluded that effects of goal engagement vary by goal contents and contexts.
Prostate Cancer Incidence in Patients on 5α-Reductase Inhibitors for Lower Urinary Tract Symptoms: A 14-Year Retrospective Study
Authors: Ahmad I. , Small D.R. , Krishna N.S. , Akhtar M.N. , Leung H.Y.
Published: January 2012

There is still much debate regarding the long-term effect of 5α-reductase inhibitors (5-ARI) on the development of prostate cancer (PC). We tested the incidence of prostate cancer and the tumour Gleason grading in a non-screened population who were prescribed 5-ARIs for lower urinary tract symptoms (LUTS). Data from a prostatic biopsy database were analysed in a retrospective study, and included a period of 14 years (01/01/1997 to 01/01/2011). Those patients who were on 5-ARIs with either finasteride or dutasteride for less than 1 year were excluded. Patients who presented with LUTS and underwent diagnostic prostatic biopsies were included in this study. This patient cohort was further categorised according to their history of 5-ARIs medication.

The incidence of PC in the 5-ARI treated group was 15.4% ( n = 22/143), comparable to that of the untreated group (16.7%, n = 332/1990) ( p = 0.7318). Mean Gleason sum score and respective grade was the same (7 = 3 + 4) (median sum score 7 (range 6–10)). Average age at the time of PC diagnosis was similar regardless of 5-ARIs treatment: 72 (range 50–84) and 73 (45–84) years for treated and untreated groups, respectively.

In this retrospective study, patients treated with 5-ARIs for LUTS had similar risk in developing PC when compared to those who did not receive 5-ARIs. The Gleason sum scores for the cancers were similar in the two groups.
The importance of measuring macroprolactin in the differential diagnosis of hyperprolactinemic patients
Authors: Lu Chih‐Chin , Hsieh Ching‐Jung
Published: January 2012

This study investigated the differences in clinical and laboratory features as well as treatment response in 70 outpatients with macroprolactinemia and monomeric hyperprolactinemia treated with dopamine agonists. After precipitation of the patients' serum samples with poly‐ethylene‐glycol (PEG), serum prolactin (PRL) levels were measured. We also measured serum levels of luteinizing hormone (LH), follicle‐stimulating hormone (FSH), estradiol for women and testosterone for men. Clinical symptoms and signs were recorded. All patients received brain magnetic resonance imaging (MRI). After excluding patients with macroadenoma, 66 patients were treated with the dopamine agonist cabergoline. After 1 year, the clinical responses to cabergoline were recorded and PRL levels measured. Of the initial 70 patients with hyperprolactinemia, 15 patients (21.4%) were found to have macroprolactinemia, while the rest had monomeric hyperprolactinemia. The two groups did not differ with regard to galactorrhea, menstrual disturbances or impotence. There were no significant group differences in serum LH, FSH, estradiol or testosterone levels. Patients with macroprolactinemia, however, had a significantly lower infertility rate than those with true hyperprolactinemia (6.7% vs. 32.7%,p= 0.005). A greater percentage of macroprolactinemic patients had normal MRI pituitary images than those with hyperprolactinemia (73.3% vs. 34.5%,p= 0.029). Compared to those with true hyperprolactinemia, patients with macroprolactinemia were found to have no significant changes in clinical features and PRL levels after 1 year of cabergoline therapy (after PEG precipitation, pre‐ and post‐PRL levels: 59.3 ± 100.2 to 13.8 ± 9.5 ng/mL vs. 6.1 ± 5.3 to 5.1 ± 4.3 ng/mL,p= 0.002). In conclusion, while macroprolactinemia is a common cause of hyperprolactinemia, many clinical and laboratory features cannot be used reliably to differentiate macroprolactinemia from true hyperprolactinemia. Routine screening for all hyperprolactinemic sera with PEG might prevent the unnecessary use of image studies and medical treatments for people with hyperprolactinemia.
Ältere Menschen im Blickpunkt des BMBF Förderschwerpunkts Präventionsforschung
Authors: Plaumann Martina , Linden Susanne , Nöcker Guido , Pawils Silke , Walter Ulla
Published: January 2012

Einleitung

Die Relevanz von Prävention zur Förderung der Arbeitsfähigkeit älterer Arbeitnehmer sowie zum Erhalt der Selbstständigkeit und Teilhabe im Alter ist erkannt. Die Erforschung wirksamer Interventionen steht in Deutschland bislang jedoch noch am Anfang. Dabei liegen die Ziele der Prävention und Gesundheitsförderung im Alter in der Vermeidung von Erkrankungen und Funktionseinbußen, Erhaltung der Unabhängigkeit und Selbstständigkeit, Erhaltung der aktiven Lebensgestaltung, Vermeidung von psychischen Erkrankungen aufgrund von Überforderung und Aufrechterhaltung eines angemessenen Systems der Unterstützung. Maßnahmen zur Erreichung dieser Ziele werden u.a. von Projekten im Förderschwerpunkt Präventionsforschung des Bundesministeriums für Bildung und Forschung (BMBF) durchgeführt und evaluiert.
Key section of the Preobrazhenka productive horizon in the Vendian–Lower Cambrian carbonate complex (Lena–Tunguska petroliferous province)
Authors: Shemin G.G. , Chernova L.S. , Potlova M.M. , Vashchenko V.A. , Doroginitskaya L.M. , Larichev A.I.
Published: January 2012

We present results of lithofacies, reservoir, geochemical, well logging, and petrophysical studies of the key section of the Vendian–Lower Cambrian Preobrazhenka productive horizon in the Lena–Tunguska province. We have considered the composition, structure, and formation conditions of the deposits as well as the intensity of postsedimentation processes and the rock geochemistry, petrophysics, and reservoir properties.
Magnetoacoustic emission of magnetites
Authors: Ivanchenko V.S. , Glukhikh I.I. , Strokina L.G. , Kheinson A.P.
Published: January 2012

We consider the parameters of magnetoacoustic emission (MAE) in magnetites from the ores of the Urals and West Siberia. It has been shown that the differences in signals are related to various types of the domain structures of samples, whose fixity is determined by the formation conditions of magnetite and the effect of superimposed physicochemical processes. On the basis of field parameters, the magnetites have been divided into three types depending on the area of magnetic fields with MAE. These parameters can serve as the typomorphic features of magnetites of different genesis.
Do subthreshold psychotic experiences predict clinical outcomes in unselected non-help-seeking population-based samples? A systematic review and meta-analysis, enriched with new results
Authors: Kaymaz N. , Drukker M. , Lieb R. , Wittchen H.-U. , Werbeloff N. , Weiser M. , Lataster T. , van Os J.
Published: January 2012

Background

The base rate of transition from subthreshold psychotic experiences (the exposure) to clinical psychotic disorder (the outcome) in unselected, representative and non-help-seeking population-based samples is unknown.

Method

A systematic review and meta-analysis was conducted of representative, longitudinal population-based cohorts with baseline assessment of subthreshold psychotic experiences and follow-up assessment of psychotic and non-psychotic clinical outcomes.

Results

Six cohorts were identified with a 3–24-year follow-up of baseline subthreshold self-reported psychotic experiences. The yearly risk of conversion to a clinical psychotic outcome in exposed individuals (0.56%) was 3.5 times higher than for individuals without psychotic experiences (0.16%) and there was meta-analytic evidence of dose–response with severity/persistence of psychotic experiences. Individual studies also suggest a role for motivational impairment and social dysfunction. The evidence for conversion to non-psychotic outcome was weaker, although findings were similar in direction.

Conclusions

Subthreshold self-reported psychotic experiences in epidemiological non-help-seeking samples index psychometric risk for psychotic disorder, with strong modifier effects of severity/persistence. These data can serve as the population reference for selected and variable samples of help-seeking individuals at ultra-high risk, for whom much higher transition rates have been indicated.
A cue-based approach to the acquisition of grammatical gender in Russian
Authors: RODINA YULIA , WESTERGAARD MARIT
Published: January 2012

This article discusses the acquisition of gender in Russian, focusing on some exceptional subclasses of nouns that display a mismatch between semantics and morphology. Experimental results from twenty-five Russian-speaking monolinguals (age 2 ; 6–4 ; 0) are presented and, within a cue-based approach to language acquisition, we argue that children rely on certain morphosyntactic micro-cues in the course of acquisition of semantic agreement. A discrepancy is observed in the acquisition of semantic agreement across the different noun classes, and this suggests that children are highly sensitive to fine distinctions in syntax and morphology and use detailed input information to make specific inferences concerning the gender of different noun classes. Furthermore, we argue that acquisition data may provide a more accurate account of how gender assignment proceeds in the mind of a speaker than has been traditionally assumed by gender assignment theories.
Functional reorganization in the developing lexicon: separable and changing influences of lexical and phonological variables on children's fast-mapping
Authors: MCKEAN CRISTINA , LETTS CAROLYN , HOWARD DAVID
Published: January 2012

Neighbourhood Density (ND) and Phonotactic Probability (PP) influence word learning in children. This influence appears to change over development but the separate developmental trajectories of influence of PP and ND on word learning have not previously been mapped. This study examined the cross-sectional developmental trajectories of influence of PP and ND on fast-mapping in thirty-eight English-speaking children aged 3 ; 01–5 ; 02, in a task varying PP and ND orthogonally. PP and ND exerted separable influences on fast-mapping. Overall, low ND supported better fast-mapping. The influence of PP changed across the developmental trajectory, ‘switching’ from a high to a low PP advantage. A potential explanation for this ‘switch’ is advanced, suggesting that it represents functional reorganization in the developing lexicon, which emerges from changes in the developing lexicon, as phonological knowledge is abstracted from lexical knowledge, over development.
Multistate outbreak ofSalmonellaserotype Typhimurium infections associated with consumption of restaurant tomatoes, USA, 2006: hypothesis generation through case exposures in multiple restaurant clusters
Authors: BEHRAVESH C. BARTON , BLANEY D. , MEDUS C. , BIDOL S. A. , PHAN Q. , SOLIVA S. , DALY E. R. , SMITH K. , MILLER B. , TAYLOR T. , NGUYEN T. , PERRY C. , HILL T. A. , FOGG N. , KLEIZA A. , MOORHEAD D. , AL-KHALDI S. , BRADEN C. , LYNCH M. F.
Published: January 2012

Multiple salmonellosis outbreaks have been linked to contaminated tomatoes. We investigated a multistate outbreak ofSalmonellaTyphimurium infections among 190 cases. For hypothesis generation, review of patients' food histories from four restaurant-associated clusters in four states revealed that large tomatoes were the only common food consumed by patients. Two case-control studies were conducted to identify food exposures associated with infections. In a study conducted in nine states illness was significantly associated with eating raw, large, round tomatoes in a restaurant [matched odds ratio (mOR) 3·1, 95% confidence interval (CI) 1·3–7·3]. In a Minnesota study, illness was associated with tomatoes eaten at a restaurant (OR 6·3, mid-P95% CI 1·05–50·4,P=0·046). State, local and federal regulatory officials traced the source of tomatoes to Ohio tomato fields, a growing area not previously identified in past tomato-associated outbreaks. Because tomatoes are commonly eaten raw, prevention of tomato contamination should include interventions on the farm, during packing, and at restaurants.
Quantifying the impact of anthropogenic nitrogen deposition on oceanic nitrous oxide
Authors: Suntharalingam Parvadha , Buitenhuis Erik , Le Quéré Corinne , Dentener Frank , Nevison Cynthia , Butler James H. , Bange Hermann W. , Forster Grant
Published: January 2012

Anthropogenically induced increases in nitrogen deposition to the ocean can stimulate marine productivity and oceanic emission of nitrous oxide. We present the first global ocean model assessment of the impact on marine N2O of increases in nitrogen deposition from the pre‐industrial era to the present. We find significant regional increases in marine N2O production downwind of continental outflow, in coastal and inland seas (15–30%), and nitrogen limited regions of the North Atlantic and North Pacific (5–20%). The largest changes occur in the northern Indian Ocean (up to 50%) resulting from a combination of high deposition fluxes and enhanced N2O production pathways in local hypoxic zones. Oceanic regions relatively unaffected by anthropogenic nitrogen deposition indicate much smaller changes (<2%). The estimated change in oceanic N2O source on a global scale is modest (0.08–0.34 Tg N yr−1, ∼3–4% of the total ocean source), and consistent with the estimated impact on global export production (∼4%).
Crustal thickness variations in northern Morocco
Authors: de Lis Mancilla Flor , Stich Daniel , Morales José , Julià Jordi , Diaz Jordi , Pazos Antonio , Córdoba Diego , Pulgar Javier A. , Ibarra Pedro , Harnafi Mimoun , Gonzalez‐Lodeiro Francisco
Published: January 2012

During the TopoIberia experiment, a total of 26 seismic broadband stations were recording in northern Morocco, providing for the first time extended regional coverage for investigating structure and seismotectonics of the southern branch of the Betic‐Rif arc, its foreland, and the Atlas domain. Here, we analyze P‐to‐S converted waves in teleseismic receiver functions to infer gross crustal properties as thickness and Vp/Vs ratio. Strong lateral variations of the crustal thickness are observed throughout the region. Crustal thicknesses vary between 22 and 44 km and display a simple geographic pattern that divides the study area into three domains: entire northwestern Morocco underlain by a thickened crust with crustal thicknesses between 35 and 44 km; northeastern Morocco affected by significant crustal thinning, with crustal thicknesses ranging from 22 to 30 km, with the shallowest Moho along the Mediterranean coast; and an extended domain of 27–34 km thick crust, farther south which includes the Atlas domain and its foreland regions. Vp/Vs ratios show normal values of ∼1.75 for most stations except for the Atlas domain, where several stations give low Vp/Vs ratios of around 1.71. The very sharp transition from thick crust in northwestern Morocco to thin crust in northeastern Morocco is attributed to regional geodynamics, possibly the realm of present‐day subcrustal dynamics in the final stage of western Mediterranean subduction. Crustal thicknesses just slightly above 30 km in the southern domain are intriguing, showing that high topography in this region is not isostatically compensated at crustal level.
Using high‐resolution distributed temperature sensing to quantify spatial and temporal variability in vertical hyporheic flux
Authors: Briggs Martin A. , Lautz Laura K. , McKenzie Jeffrey M. , Gordon Ryan P. , Hare Danielle K.
Published: January 2012

Hyporheic flow can be extremely variable in space and time, and our understanding of complicated flow systems, such as exchange around small dams, has generally been limited to reach‐averaged parameters or discrete point measurements. Emerging techniques are starting to fill the void between these disparate scales, increasing the utility of hyporheic research. When ambient diurnal temperature patterns are collected at high spatial resolution across vertical profiles in the streambed, the data can be applied to one‐dimensional conduction‐advection‐dispersion models to quantitatively describe the vertical component of hyporheic flux at the same high spatial resolution. We have built on recent work by constructing custom fiber‐optic distributed temperature sensors with 0.014 m spatial resolution that are robust enough to be installed by hand into the streambed, maintain high signal strength, and permit several sensors to be run in series off a single distributed temperature sensing unit. Data were collected continuously for 1 month above two beaver dams in a Wyoming stream to determine the spatial and temporal nature of vertical flux induced by the dams. Flux was organized by streambed morphology with strong, variable gradients with depth indicating a transition to horizontal flow across a spectrum of hyporheic flow paths. Several profiles showed contrasting temporal trends as discharge decreased by 45%. The high‐resolution thermal sensors, combined with powerful analytical techniques, allowed a distributed quantitative description of the morphology‐driven hyporheic system not previously possible.
The role of deimination in ATP5b mRNA transport in a transgenic mouse model of multiple sclerosis
Authors: Ding Di , Enriquez‐Algeciras Mabel , Dave Kunjan R , Perez‐Pinzon Miguel , Bhattacharya Sanjoy K
Published: January 2012

Deimination refers to conversion of protein‐bound arginine into citrulline. An mRNA carrier, RNA binding export factor (REF), present on mitochondria undergoes loss of deimination with impaired ATP5b mRNA transport in ND4 mice (model of multiple sclerosis) compared with the controls. We present evidence of (1) reduced ATP5b mRNA binding strength of non‐deiminated REF compared with deiminated REF, (2) impaired ATP5b mRNA transport in ND4 mice and (3) reduced mitochondrial ATP synthase activity on inhibition of deimination in PC12 cells. Impaired deimination of REF and defect in mitochondrial mRNA transport are critical factors in mitochondrial dysfunction in ND4 mice.
Review of typical vs. synthesized energy modeling weather files
Authors: Al-Mofeez Ibraheem A. , Numan Mohammad Y. , Alshaibani Khalid A. , Al-Maziad Faris A.
Published: January 2012

This paper reviews the widely used weather file formats, namely, typical meteorological year (TMY) of evolved versions, test reference year (TRY), weather year for energy calculation (WYEC), design reference year (DRY) as well as synthetically generated meteorological year (SMY) used in energy simulation and renewable-energy studies. This paper examines the fundamentals underlying their structure as to how they support and interface with the available energy simulation and modeling software as well as computer systems on which they operate. The differences in TMY, TRY, WYEC, DRY, and SMY in the selection and weighting of weather parameters are discussed, outlining the pros and cons of each type. Finally, sample dry bulb temperature regimes from SMY and TMY weather files are presented to show the differences in average monthly maximum, minimum, and mean temperatures.
Frequency dependent dielectric properties of Cu0.5Tl0.5Ba2Ca2(Cu3-yMy)O10-δ superconductor
Authors: Mumtaz M. , Khan Nawazish A. , Khan Sajid
Published: January 2012

The frequency dependent dielectric properties such as dielectric constants (ɛ/r, ɛ//r), absolute dielectric loss |tanδ|, and ac-conductivity (σac) of Cu0.5Tl0.5Ba2Ca2(Cu3-yMy)O10-δ (M = Si, Ge, Sn, y = 0, 1) superconductor have been investigated by means of capacitance (C) and conductance (G) measurements with the test frequency (f) in the range of 10 KHz to 10 MHz at various temperatures from superconducting state to normal conducting state. The negative capacitance has been observed in all Cu0.5Tl0.5Ba2Ca2(Cu3-yMy)O10-δ samples. The large values of negative dielectric constant (ɛ/r) at lower frequencies and temperatures are linked with reduced thermal vibrations of the atoms due to which polarizability has been enhanced. The decreased value of dielectric constant observed in the Ge-doped samples may possibly be linked with its greater electronegativity (EN) and less polarization. The electronegativity of Si and Sn has approximately the same values as that of Cu, so almost all the dielectric properties do not vary significantly in Si-doped Cu0.5Tl0.5Ba2Ca2(Cu2Si1)O10-δ and Sn-doped Cu0.5Tl0.5Ba2Ca2(Cu2Sn1)O10-δ samples. These experimental investigations on dielectric properties of Cu0.5Tl0.5Ba2Ca2(Cu3-yMy)O10-δ superconductor have shown lower dielectric loss and higher ac-conductivity at all frequencies and temperatures as compared to that of other high Tc superconductor families. The decreased dielectric loss in Cu0.5Tl0.5Ba2Ca2(Cu3-yMy)O10-δ samples suggests that the polarization is most likely arising from the charge carriers between Cu0.5Tl0.5Ba2O4-δ charge reservoir layer and conducting CuO2/MO2 planes; since the charge reservoir layer has localized charge carriers at Ba+2, Tl+3, and Cu+2 sites, whereas CuO2/MO2 planes contain mobile charge carriers, which are displaced from their equilibrium position by external applied ac-field.
Modeling upconversion of erbium doped microcrystals based on experimentally determined Einstein coefficients
Authors: Fischer Stefan , Steinkemper Heiko , Löper Philipp , Hermle Martin , Goldschmidt Jan Christoph
Published: January 2012

The upconversion of infrared photons is a promising possibility to enhance solar cell efficiency by producing electricity from otherwise unused sub-band-gap photons. We present a rate equation model and the relevant processes in order to describe the upconversion of near-infrared photons. The model considers stimulated and spontaneous processes, multi-phonon relaxation, and energy transfer between neighboring ions. The input parameters for the model are experimentally determined for the material system, β-NaEr0.2Y0.8F4. The determination of the transition probabilities, also known as the Einstein coefficients, is the focus of the parameterization. The influence of multi-phonon relaxation and energy transfer on the upconversion are evaluated and discussed in detail. Since upconversion is a non-linear process, the irradiance dependence of the simulations is investigated and compared to the experimental data of quantum efficiency measurements. The results are very promising and indicate that upconversion is reasonably physically described by the rate equations. Therefore, the presented model will be the basis for further simulations concerning various applications of upconversion, such as in combination with plasmon resonances in metal nanoparticles.
Visualizing the zero order basis of the spectroscopic Hamiltonian
Authors: Barnes George L. , Kellman Michael E.
Published: January 2012

Recent works have shown that a generalization of the spectroscopic effective Hamiltonian can describe spectra in surprising regions, such as isomerization barriers. In this work, we seek to explain why the effective Hamiltonian is successful where there was reason to doubt that it would work at all. All spectroscopic Hamiltonians have an underlying abstract zero-order basis (ZOB) which is the “ideal” basis for a given form and parameterization of the Hamiltonian. Without a physical model there is no way to transform this abstract basis into a coordinate representation. To this end, we present a method of obtaining the coordinate space representation of the abstract ZOB of a spectroscopic effective Hamiltonian. This method works equally well for generalized effective Hamiltonians that encompass above-barrier multiwell behavior, and standard effective Hamiltonians for the vicinity of a single potential minimum. Our approach relies on a set of converged eigenfunctions obtained from a variational calculation on a potential surface. By making a one-to-one correspondence between the energy eigenstates of the effective Hamiltonian and those of the coordinate space Hamiltonian, a physical representation of the abstract ZOB is calculated. We find that the ZOB basis naturally adjusts its complexity depending on the underlying nature of phase space, which allows spectroscopic Hamiltonians to succeed for systems sampling multiple stationary points.
Numerical simulation of the pre-ionization processes during nanosecond-pulse discharge in nitrogen
Authors: Levko D. , Gurovich V. Tz. , Krasik Ya. E.
Published: January 2012

The pre-ionization of nitrogen gas by high-voltage nanosecond pulse discharges is studied using one-dimensional particle-in-cell numerical simulations. The comparison between the various mechanisms of pre-ionization, i.e., by runaway electrons, x-rays, and ultraviolet radiation, is presented. It is shown that runaway electrons produce a much higher number of electron-ion pairs than those generated by x-rays, which accompany the process of runaway electron generation. Also, results of simulations showed that among photo-ionization mechanisms the most significant gas pre-ionization is caused by x-rays generated in the process of impact ionization of the K-shell of nitrogen atoms.
A new fragment-based approach for calculating electronic excitation energies of large systems
Authors: Ma Yingjin , Liu Yang , Ma Haibo
Published: January 2012

We present a new fragment-based scheme to calculate the excited states of large systems without necessity of a Hartree-Fock (HF) solution of the whole system. This method is based on the implementation of the renormalized excitonic method [M. A. Hajj et al., Phys. Rev. B 72, 224412 (2005)10.1103/PhysRevB.72.224412] at ab initio level, which assumes that the excitation of the whole system can be expressed by a linear combination of various local excitations. We decomposed the whole system into several blocks and then constructed the effective Hamiltonians for the intra- and inter-block interactions with block canonical molecular orbitals instead of widely used localized molecular orbitals. Accordingly, we avoided the prerequisite HF solution and the localization procedure of the molecular orbitals in the popular local correlation methods. Test calculations were implemented for hydrogen molecule chains at the full configuration interaction, symmetry adapted cluster/symmetry adapted cluster configuration interaction, HF/configuration interaction singles (CIS) levels and more realistic polyene systems at the HF/CIS level. The calculated vertical excitation energies for lowest excited states are in reasonable accordance with those determined by the calculations of the whole systems with traditional methods, showing that our new fragment-based method can give good estimates for low-lying energy spectra of both weak and moderate interaction systems with economic computational costs.
Shaping magnetic fields with soft ferromagnets: Application to levitation of superconductors
Authors: Del-Valle Nuria , Agramunt-Puig Sebastia , Navau Carles , Sanchez Alvaro
Published: January 2012

Soft ferromagnetic materials have an important role in technology, for increasing magnetic field in specific regions, as in the core of transformers, and for properly modifying the magnetic field in particular shapes. Here we develop a numerical model that allows study of the response of a soft ferromagnet bar with arbitrary cross section and infinite susceptibility when a magnetic field with translational symmetry is applied. This theoretical tool will enable us to analyze the shape and position of the soft ferromagnet to properly modify the magnetic field in the areas of interest. The model can also simulate hybrid systems that contain a superconducting bar as well, considering the mutual interaction between the soft ferromagnetic and the superconducting materials. In particular, we analyze the levitation force of a superconducting bar immersed in the magnetic field created by a guideway of two permanent magnet bars with uniform horizontal magnetization and a soft ferromagnet bar in between. The results show that by placing the soft ferromagnet with an optimized height the levitation force is enhanced.
Slow sound propagation in a sonic crystal linear waveguide
Authors: Cicek Ahmet , Adem Kaya Olgun , Yilmaz Mukremin , Ulug Bulent
Published: January 2012

A linear waveguide along the [11] direction of a triangular sonic crystal, composed of aluminum cylinders in air is shown both experimentally and numerically to facilitate slow sound propagation. Supercell-based calculations through the finite element method reveal a band centered at approximately 16.0 kHz with 255 Hz span, exhibiting linear variation away from band edges, for the lattice constant and cylinder radii of 21.7 mm and 10.0 mm, respectively. The experimental setup is based on monitoring the propagation of a Gaussian-enveloped sinusoidal pulse at 16.0 kHz inside the waveguide. Numerical behavior of the Gaussian pulse is investigated by time-dependent finite-element computations. The experimental and numerical group velocities are found to be 26.7 m/s and 22.6 m/s, respectively. Being congruous with the experimental findings, numerical transient study of the system reveals significant longitudinal compression commensurate with the calculated group index.
A new borehole wire extensometer with high accuracy and stability for observation of local geodynamic processes
Authors: Mentes Gy.
Published: January 2012

Very stable and reliable instruments with high accuracy are required in field measurements for continuous monitoring local geodynamic processes, such as tectonic movements, ground motions in landslide prone areas, etc. A sensitive borehole wire extensometer with low energy consumption was developed in the Geodetic and Geophysical Research Institute of the Hungarian Academy of Sciences to observe very small vertical movements (in the order of a few millimeters) of the upper layer of the soil due to hydrological, meteorological and biological processes. The newly developed instrument eliminates the disadvantages of the borehole wire extensometers which are presently used. Its sensitivity and stability are much higher than these parameters of the previous instruments. The instrument is able to measure distance variations without instrumental drift in a range of 0–4 mm with a resolution of better than 1 μm. Since the effect of the yearly temperature variations can be easily removed from the extensometric data record, the compensation for the short-periodic (daily) thermal effects on the instrument was of high priority during the design of the instrument. This paper describes the construction and calibration of the extensometer. The extensometer was installed for monitoring vertical ground movements due to hydro-meteorological processes on the high loess wall of the Danube River at Dunaföldvár, Hungary. The efficiency of the temperature compensation of the instrument was investigated in detail on the basis of the measured data series.
Photocarrier collection from depletion layer of LaMnO3
Authors: Fujioka J. , Nakamura M. , Kawasaki M. , Tokura Y.
Published: January 2012

We have investigated the bias electric field dependence of the photocurrent for LaMnO3/Nb-doped SrTiO3 heterostructures. The photocarriers generated in LaMnO3 are more efficiently injected into Nb-doped SrTiO3 when the reverse bias voltage is applied. Within the rigid-band scheme, this can be attributed to the bias voltage–induced expansion of the depletion layer. Although LaMnO3 is a typical electron-correlated insulator, its interface band profile under the bias voltage is well modeled as that of the conventional dilutely doped p-type semiconductor.
Aesthetic Preference for Spatial Composition in Multiobject Pictures
Authors: Leyssen Mieke H R , Linsen Sarah , Sammartino Jonathan , Palmer Stephen E
Published: January 2012

Five experiments examined preferences for horizontal positions in multiobject pictures. In Experiment 1, each picture contained a fixed object and an object whose position could be adjusted to create the most (or least) aesthetically pleasing image. Observers placed the movable object closer to the fixed object when the objects were related than when they were unrelated (a relatedness bias) but almost never overlapped them (a separation bias). Experiment 2 showed that these results were not due to demand characteristics by replicating them almost exactly in a between-participants design. In Experiment 3, preference rankings revealed a strong relatedness bias together with an inward bias toward the spatial envelope of objects to point into the frame. A weak balance effect was evident in a multiple regression analysis. Experiment 4 replicated the inward bias for the spatial envelope using multiobject groups. Experiment 5 generalized the above findings for different objects when observers had to choose between image pairs that differed only in interobject distance or degree of balance. Strong relatedness effects were again present, but there was no evidence of any preference for balance.
Growth Performance and Tissue Fatty Acid Composition of Largemouth Bass Fed Diets Containing Fish Oil or Blends of Fish Oil and Soy-Derived Lipids
Authors: Laporte Jérôme , Trushenski Jesse
Published: January 2012

Dietary fatty acid (FA) composition influences the composition of fish tissues to a greater or lesser extent depending on the proportion of saturated FAs (SFAs) and medium-chain (MC) polyunsaturated FAs (PUFAs) that the feed contains. Our purpose was to evaluate the growth performance and tissue composition of largemouth bass Micropterus salmoides that were fed diets containing soy-derived lipids modified to contain more SFAs and less MC-PUFAs. Triplicate tanks of largemouth bass (∼1.6 g) were fed diets containing fish oil (FO diet) or 50:50 blends of fish oil and low-18:3(n-3) soybean oil, hydrogenated soybean oil (HYD-SBO diet), or SFA-enriched soybean oil (SFA-SBO diet). After 10 weeks, production performance was unaffected by diet, and weight gain (mean ± SE = 518 ± 19%), feed conversion ratio (1.29 ± 0.03), specific growth rate (2.59 ± 0.04% of body weight/d), and feed intake (1.42 ± 0.03% of body weight/d) indicated that all diets were accepted and well utilized. Carcass FA composition changed to reflect the diet, but composition of largemouth bass that were fed the HYD-SBO and SFA-SBO feeds was not markedly different from that of fish given the FO feed. Fish oil can be spared without affecting production performance of juvenile largemouth bass; however, to minimize changes to tissue FA profile, soy lipids containing more SFAs and less MC-PUFAs may be most appropriate.
Genetic Variation Analysis in Wild and Cultured Subpopulations of Small Abalone Haliotis diversicolor Estimated by Microsatellite Markers
Authors: You Weiwei , Zhan Xin , Wang Dexiang , Li Weidong , Luo Xuan , Ke Caihuan
Published: January 2012

The small abalone Haliotis diversicolor is an economically important shellfish species in southern China. Wild (Japanese, Guangdong, and Hainan) and cultured (Taiwanese and Vietnamese) subpopulations of small abalone were examined using seven microsatellite loci to assess the levels of genetic diversity and the degree of genetic differentiation among them. These seven microsatellite markers showed a high level of polymorphism. A total of 209 alleles were detected, with an average of 29.86 alleles per locus among the five subpopulations. The average observed heterozygosities per locus ranged from 0.733 in the Japanese subpopulation to 0.804 in the Hainan subpopulation, while the average expected heterozygosities per locus ranged from 0.909 in the Vietnamese subpopulation to 0.940 in the Guangdong subpopulation. Values for the differentiation index D  est varied from 0.1071 to 0.4020 among different subpopulations. The values for genetic distance (D  A) ranged from 0.244 to 0.409, with an average of 0.294. Both D  est and D  A showed that the largest distance was between the Japanese and Vietnamese subpopulations. Principal coordinate analysis was performed for all subpopulations and loci using genetic distance to summarize genetic relationships. The analysis indicated a grouping of the three wild subpopulations (Japanese, Guangdong, and Hainan). The Vietnamese subpopulation was plotted separately from others. The information on the genetic variation and differentiation in the wild and cultured subpopulations obtained in this study is useful for the development of guidelines for genetic breeding programs for small abalone.
Enhancement of photomultiplier sensitivity with anti-reflective layers
Authors: Harmer Stuart William , Townsend Peter David , Bowring Nicholas John
Published: January 2012

Photomultipliers are fast, sensitive and low noise light detectors which operate across the ultraviolet–optical–near infra red region of the electromagnetic spectrum. Sensitivity is determined by the composition of the photocathode layer in which incident photons excite photoelectrons and the thickness of this layer. Incident light is partially reflected from and partially transmitted through the photocathode layer, which is typically ∼20 nm thick, and this energy is unavailable for photoelectron excitation, limiting sensitivity. Typical reflectance and transmittance values at 500 nm are 21% and 33%, respectively, for KCsSb; 27% and 24% for RbCsSb and 36% and 35% for Na2SbK : Cs. These substantial losses can be reduced by the addition of one or more transparent impedance matching layers between the photomultiplier tube (PMT) window and the photocathode, resulting in enhanced sensitivity without effecting the PMT geometry, photocathode deposition process or altering the acceptance angle of the photomultiplier. The impedance matching serves to reduce reflectance losses, increasing cathode absorptance. By using published measurements of the dispersive properties of bialkali and trialkali (S20) photocathode compositions, accurate modelling of the electromagnetic field distribution within the photocathode layer is possible. This model facilitates the prediction of the enhancement of sensitivity obtainable with an anti-reflective layer of zirconium dioxide (zirconia). The authors present the enhancement factors possible with standard bialkali and trialkali photocathode compositions using the material zirconia for impedance matching. Enhancement factors up to 27% and 38% are predicted for KCsSb and RbCsSb photocathodes, respectively, while an enhancement factor of up to 44% is predicted for the S20 photocathode.
Structural, morphological and piezoresponse studies of Pr and Sc co-substituted BiFeO3 ceramics
Authors: Coondoo Indrani , Panwar Neeraj , Bdikin I , Puli V S , Katiyar R S , Kholkin A L
Published: January 2012

Pristine (BiFeO3), Pr and Sc co-substituted Bi0.9Pr0.1Fe1−x
Sc
x
O3 (0.01 ⩽ x ⩽ 0.07) ceramics have been investigated for their structural (including x-ray diffraction and Raman), morphological and piezoresponse behaviour. Secondary phases observed in pristine BiFeO3 (BFO) ceramic were significantly suppressed in the co-substituted samples. Grain size decreased in the co-substituted samples. Raman study revealed ten active phonon modes which remained almost invariant with co-substitution. Out-of-plane piezoresponse (OPP-PFM) exhibited negative self-polarization effect in the virgin state (without any poling) which has been explained in terms of built-in electric field. The self-polarization effect is largest in 3% Sc co-substituted sample. Poling with ±30 V dc voltage demonstrated both positive and negative domains. Maximum difference in the peak values (from histograms) of such opposite domains was observed in the Bi0.9Pr0.1Fe0.99Sc0.01O3 sample. Information from local measurements (such as PFM) should be useful in deciding such multiferroic materials for device application.
Ezrin regulates microvillus morphogenesis by promoting distinct activities of Eps8 proteins
Authors: Zwaenepoel Ingrid , Naba Alexandra , Menezes Lyra Da Cunha Marcel , Del Maestro Laurence , Formstecher Etienne , Louvard Daniel , Arpin Monique
Published: January 2012

The mechanisms that regulate actin filament polymerization resulting in the morphogenesis of the brush border microvilli in epithelial cells remain unknown. Eps8, the prototype of a family of proteins capable of capping and bundling actin filaments, has been shown to bundle the microvillar actin filaments. We report that Eps8L1a, a member of the Eps8 family and a novel ezrin-interacting partner, controls microvillus length through its capping activity. Depletion of Eps8L1a leads to the formation of long microvilli, whereas its overexpression has the opposite effect. We demonstrate that ezrin differentially modulates the actin-capping and -bundling activities of Eps8 and Eps8L1a during microvillus assembly. Coexpression of ezrin with Eps8 promotes the formation of membrane ruffles and tufts of microvilli, whereas expression of ezrin and Eps8L1a induces the clustering of actin-containing structures at the cell surface. These distinct morphological changes are neither observed when a mutant of ezrin defective in its binding to Eps8/Eps8L1a is coexpressed with Eps8 or Eps8L1a nor observed when ezrin is expressed with mutants of Eps8 or Eps8L1a defective in the actin-bundling or -capping activities, respectively. Our data show a synergistic effect of ezrin and Eps8 proteins in the assembly and organization of actin microvillar filaments.
Targeting May Not Be So Bad
Authors: Kenworthy Lane
Published: January 2012

The hypothesis that targeting in social policy reduces political support and thereby lessens redistributive effort is a sensible one. But the experience of the rich countries in recent decades suggests reason to question it.
4 Brewing Nation: War, Taxes, and the Growth of the British Beer Industry in the Eighteenth and Nineteenth Centuries
Authors: Nye John V. C.
Published: January 2012

As a result of war with France, British tariffs were raised to protect domestic beverage production. This helped promote the beer industry during the infancy of industrial brewing in the 18th century. But protection also led to monopoly controls in order to promote easier taxation and greater regulatory oversight. This chapter shows that this severely distorted the consumption of alcohol and the production of domestic substitutes like beer in Britain, but that it also enabled the state to grow by providing it with a mechanism for dramatically raising taxes to fund the century's many wars. Reversing protection in the 19th century was complicated and fraught with interference from domestic lobbies that hampered the British move to free trade.