bluuebunny/crossref_metadata_2025 huggingface dataset:
(P2-78) The Unique Role of Emergency Medical Services (EMS) in an Earthquake – A Community Based Approach
Authors: Jaffe E. , Ben-zvi S.
Published: May 2011

Introduction

The goal of most EMS is to provide treatment to those in need of urgent medical care, with the purpose of satisfactorily treating the problem, or arranging for timely removal of the patient to the next point of definitive care. Earthquakes are among the most destructive types of natural disasters, striking suddenly with no accurate method of prediction or warning, thereby taking a heavy toll on life, injury and property. The damage created affects all aspects of the community - transportation, telecommunication, and infrastructure and can easily overwhelm local health services, damage clinics, hospitals and render them useless.

Aim

To review the pertinent literature and to analyze the information in order to set practical guidelines for EMS work in earthquakes with a community-based approach.

Results

Survival of casualties extricated from under the rubble depends upon early medical interventions by emergency teams on site. EMS needs to strive for: • early arrival • early qualified treatment • Earthquakes differ from other disasters, where the system is intact.: early transport and definitive care. • They present a vast number of patients • problems concerning availability of medical personnel, • accessibility to patients, means of transportation & communication.

Conclusions

A routine national community-based approach will strengthen the ability to provide early response in both daily and disastrous events, improving both morbidity and mortality rates. Possibly no immediate definitive care.
(P2-91) EMS Trauma Triage: Does the Red-Blue Criteria Enable Overtriage?
Authors: Higgins D.M. , Thaxton R.E.
Published: May 2011

Introduction

With the current need for effective trauma center utilization, understanding how current trauma triage criteria may promote overtriage will enable both field and hospital teams to provide the most appropriate patient care. It is hypothesized that current Southwest Texas trauma criteria promote overtriage by prehospital emergency medical services (EMS) of patients in favor of a Level 1 trauma facility when compared to physician assessment and Injury Severity Score (ISS).

Methods

This prospective, observational study at a Southwest Texas military Level 1 trauma center compared adult trauma patients' prehospital status noted by EMS personnel with the triage criteria documented by the treating emergency physician. The patients were divided into four groups: Prehospital Criteria Met or Not Met; Arrival Criteria Met or Not Met. Each patient's ISS and mechanism of injury were also collected and compared to initial assessment for predictive value. Descriptive statistics were used.

Results

The study enrolled 278 adult trauma patients. EMS reported Level 1 trauma status similar to physician assessment (60.1% vs. 59.7%, respectively). The rates patients met Level 1 trauma status corresponded with trauma severity when compared to the ISS. Assessment between EMS and physicians for ISSs were similar among the four groups. Comparisons using multivariate analysis of the four groups found similar ISSs, except for the Prehospital Criteria Met/Arrival Criteria Not Met group. Seventy-five percent of these patients were assigned an ISS in the Minor (ISS < 9) category (p = 0.013).

Conclusion

Trauma triage criteria assessment skills were similar between EMS personnel and emergency physicians except for identifying minor trauma patients. While the criteria generally led to overtriage, EMS crews appear to overtriage minor trauma patients at a much higher rate.
(P2-95) Pre-Decontamination Triage for Hazmat Casualties Involving an Unknown Chemical
Authors: Chan K.C.
Published: May 2011

Pre-decontamination triage aims to prioritize the use of decontamination facilities for casualties based on their severity of injuries. Pre-decontamination triage aims to: (1) ensure severe casualties undergo early decontamination, in order for them to receive early definitive medical treatment post-decontamination; (2) provide basic life support measures, e.g., stopping external hemorrhage, use of bag valve mask ventilation, even before decontamination; (3) early administration of antidotes for organophosphate poisoning (if present). Triage during the pre-decontamination takes place in the warm zone. Triage personnel must don personnel protective equipment (PPE) of level C or above. Donning PPE will decrease the visual, aural and tactile senses of triage personnel, adversely affecting their ability to carry out effective triage. With these limitations in mind, a pre-decontamination triage system was devised, modified from the Simple Triage and Rapid Treatment (START) protocol. Assessment will be based on the presence of airway, breathing, or circulatory compromises, or changes in mental status, similar to the START protocol. Recognition of organophosphate poisoning prior to decontamination is emphasized, as the toxidrome is recognizable and specific. Once organophosphate poisoning is diagnosed, the severity of the poisoning is graded and antidote administration is carried out using the Mark I Kits. The need to be certain of the diagnosis of organophosphate poisoning before administration of Mark I Kits is emphasized. The diagnosis may not be apparent initially to the triage personnel till a spectrum of patients with toxidromes suggestive of organophosphate poisoning has been seen.
(P2-96) A Single, Simple Triage Method
Authors: Raviolo M. , Bortolin M. , Vivalda M. , Bono D.
Published: May 2011

Introduction

At this time, no triage method is considered better than another in comparison to the outcome of the casualties. It is important and useful to identify a triage method that can be used for both adults and children at the same time. It should consider the anatomical and physiological differences between adults, children, and infants.

Objectives

To revise and adapt the current triage system in use in the Piemonte Emergency Medical Services for the first triage in a validated method that is effective for adults, children, and babies in order to unify and simplify the triage system.

Methods

In accordance with pediatricians, the “Triage Sieve” procedure and parameters were revised into a single method.

Results

Setting the height of the casualty was considered to be both quick and easy. In this revised method, all the casualties are classified with the sieve methods, but some changes have been introduced. Casualties with a stature < 59 cm are classified as infants, and are therefore priority T1 (red) in every case. Casualties > 60 cm but < 120 cm in stature are classified as children. Children with a respiratory rate < 15 or > 40 breaths per minute and a heart rate < 80 or > 160 beats per minute are classified as T1.

Conclusions

Children will probably be over-triaged in this method, but the authors do not consider that a substantial problem. This first triage system is simple and effective. But, it has not yet been tested effectively during an actual mass-casualty incident or disaster.
(P2-98) Disease Pattern in a Rural Setting Three Weeks After the 2008 Sichuan, China Earthquake—Hong Kong Red Cross Basic Health Clinic in Yanmen
Authors: Hung K. , Chan E.Y.Y. , Lam E. , Rainer T. , Graham C.
Published: May 2011

Background

The Sichuan earthquake on 12 May 2008 with a magnitude of 8.0 killed > 87,000 people. The response of the Hong Kong Red Cross (HKRC) included a basic healthcare team to a small rural town called Yanmen three weeks after the earthquake. The objective of this study was to review HKRC's medical records to identify the disease pattern in the Chinese rural setting post earthquake.

Methods

A cross-sectional, record-based study of all patients treated by the HKRC basic healthcare team from 01 June to 19 June 2008. This retrospective study studied the medical records collected during the clinical consultations, and descriptive analysis was performed for the demographic and clinical information. Blood pressure measurement was classified according to the JNC-7 classification, and the age- and gender-specific prevalence of hypertension was sought.

Results

A total of 2,034 cases were seen during the 19-day period with daily attendance ranging from 73 to 153 cases. Musculoskeletal, respiratory, and gastrointestinal problems were the top three categories and accounted for 30.4, 17.4, and 12.7% respectively. Trauma accounted for 5.4% of the cases attended, and 26.0% of the injuries were related to the earthquake. A total of 38.7% of the consultations were for medical problems that existed before the earthquake. A total of 43.4% patients with blood pressure measurements were above the recognized cutoff for hypertension.

Conclusions

Due to the impact and time phase post disaster, trauma, and injuries directly resulting from the earthquake did not contribute to a large number of cases. However, the management of chronic illness was an important issue, especially with the excessive prevalence of high blood pressure found in this study. Further studies to investigate the relationship between chronic diseases including hypertension and post-earthquake conditions are needed.
Representing first-order causal theories by logic programs
Authors: FERRARIS PAOLO , LEE JOOHYUNG , LIERLER YULIYA , LIFSCHITZ VLADIMIR , YANG FANGKAI
Published: May 2011

Nonmonotonic causal logic, introduced by McCain and Turner (McCain, N. and Turner, H. 1997. Causal theories of action and change. In Proceedings of National Conference on Artificial Intelligence (AAAI), Stanford, CA, 460–465) became the basis for the semantics of several expressive action languages. McCain's embedding of definite propositional causal theories into logic programming paved the way to the use of answer set solvers for answering queries about actions described in such languages. In this paper we extend this embedding to nondefinite theories and to the first-order causal logic.
Identifying QTLs for cold-induced resistance to Microdochium nivale in winter triticale
Authors: Szechyńska-Hebda Magdalena , Wędzony Maria , Tyrka Mirosław , Gołębiowska Gabriela , Chrupek Małgorzata , Czyczyło-Mysza Ilona , Dubas Ewa , Żur Iwona , Golemiec Elżbieta
Published: May 2011

Snow mould caused by Microdochium nivale (Fr.) Samuels & Hallett is the most widespread seedling disease in winter cereals. Due to the complexity of the resistance mechanisms, a poorly understood genetic background and strong interaction with winter weather conditions, it is difficult to assess the resistance of triticale cultivars via conventional inoculation methods. Genetic resistance is the most economical and environmental friendly way to control M. nivale infection; therefore, the objective of this study was to detect the quantitative trait loci (QTLs) associated with resistance components of winter triticale in a mapping population derived from a cross of the ‘Modus’ (partly resistant) and ‘SaKa 3006’ (sensitive) varieties. High-resolution mapping was conducted by using 1518 molecular markers (diversity arrays technology, simple sequence repeat and amplified fragment length polymorphism). Partial resistance components assessed in this study, i.e. candidate QTLs, were detected on chromosomes 1B, 2A, 3A, 3B, 5A, 5B, 6A, 6B and 7B, whereas QTLs describing overall seedling vitality in non-infected control plants were located on chromosomes 1B, 2B, 3A, 5A, 7B and 7R.
Acceptance of Cosmetic Surgery Among British Female University Students
Authors: Swami Viren , Campana Angela Nogueira , Coles Rebecca
Published: May 2011

Although patients of cosmetic surgery are increasingly ethnically diverse, previous studies have not examined ethnic differences in attitudinal dispositions toward cosmetic surgery. In the present study, 751 British female university students from three ethnic groups (Caucasians, South Asians, and African Caribbeans) completed measures of acceptance of cosmetic surgery, body appreciation, self-esteem, and demographic variables. Initial between-group analyses showed that Caucasians had lower body appreciation and self-esteem than Asian and African Caribbean participants. Importantly, Caucasians had higher acceptance of cosmetic surgery than their ethnic minority counterparts, even after controlling for body appreciation, self-esteem, age, and body mass index. Further analyses showed that ethnicity accounted for a small proportion of the variance in acceptance of cosmetic surgery, with body appreciation and self-esteem emerging as stronger predictors. Possible reasons for ethnic differences in acceptance of cosmetic surgery are discussed in Conclusion.
Two Conceptualizations of Dyadic Coping and Their Potential for Predicting Relationship Quality and Individual Well-Being
Authors: Bodenmann Guy , Meuwly Nathalie , Kayser Karen
Published: May 2011

Dyadic coping has received increased attention during the last decade, both in theory and empirical studies. Two main models of dyadic coping are proposed in the current literature: (1) a comparative approach in which each partner’s individual coping is compared with the other’s individual coping with regard to congruence or discrepancy and (2) a systemic model where dyadic coping is conceptualized as an interactive and reciprocal process. In this study, the predictive power of these two different models of dyadic coping is examined regarding relationship quality and well-being. The study is conducted with 443 Swiss couples. Results reveal that both dyadic coping measures are related to relationship quality and psychological well-being. However the systemic dyadic coping measure is a stronger predictor than the discrepancy measure for relationship quality. Both measures show weaker associations with well-being. Findings are discussed with regard to theoretical issues and their implication for practical work.
Low‐temperature thermochronology of northern Baja California, Mexico: Decoupled slip‐exhumation gradients and delayed onset of oblique rifting across the Gulf of California
Authors: Seiler Christian , Fletcher John M. , Kohn Barry P. , Gleadow Andrew J. W. , Raza Asaf
Published: May 2011

The northern Gulf Extensional Province displays key structural relationships that characterize the magnitude, direction, and timing of Neogene rift‐related transtension during the opening of the Gulf of California. Apatite fission track and (U‐Th)/He thermochronology from the Sierra San Felipe document moderate cooling (4°C/Myr–7°C/Myr) during the early Paleogene associated with progressive unroofing caused by erosional downwearing of the ancestral Peninsular Ranges. Beginning at ∼45–35 Ma, a period of tectonic quiescence with low cooling rates (≤1°C/Myr) marks the development of a regional Oligocene‐Miocene peneplain. Rift‐related exhumation began at ∼9–7 Ma and attains ∼2.5 km in the hinges of two antiformal megamullions. Decoupling between exhumation and finite displacement in certain fault segments is explained by vertical deflections associated with extension‐perpendicular folding of the fault surfaces. The main faults of the detachment system were active contemporaneously, thus forming a mechanically linked array of large‐displacement normal faults in the hanging wall of the Main Gulf Escarpment. The Late Miocene onset of transtension in the Sierra San Felipe suggests that widespread deformation may only have localized in the Gulf Extensional Province between ∼9 and 7 Ma, some ∼3–5 Ma after a major plate reorganization associated with cessation of subduction in the trench to the west. Between ∼12 Ma and ∼9–7 Ma, plate boundary shearing was likely distributed between the continental borderland west of Baja California and the southern Basin and Range province in Mexico.
Persistent El Niño–Southern Oscillation variation during the Pliocene Epoch
Authors: Scroxton N. , Bonham S. G. , Rickaby R. E. M. , Lawrence S. H. F. , Hermoso M. , Haywood A. M.
Published: May 2011

There is an urgent requirement to understand how large fluctuations in tropical heat distribution associated with the El Niño–Southern Oscillation (ENSO) will respond to anthropogenic emissions of greenhouse gases. Intervals of global warmth in Earth history provide a unique natural laboratory to explore the behavior of ENSO in a warmer world. To investigate interannual climatic variability, specifically ENSO, in the mid‐Piacenzian Warm Period (mPWP) (3.26–3.03 Ma), we integrate observations from the stable isotopes of multiple individual planktonic foraminifera from three different species from the eastern equatorial Pacific with ENSO simulations from the Hadley Centre Coupled Model version 3 (HadCM3), a fully coupled ocean‐atmosphere climate model. Our proxy data and model outputs show persistent interannual variability during the mPWP caused by a fluctuating thermocline, despite a deeper thermocline and reduced upwelling. We show that the likely cause of the deeper thermocline is due to warmer equatorial undercurrents rather than reduced physical upwelling. We conclude that the mPWP was characterized by ENSO‐related variability around a mean state akin to a modern El Niño event. Furthermore, HadCM3 predicts that the warmer Pliocene world is characterized by a more periodic, regular‐amplitude ENSO fluctuation, suggestive that the larger and deeper west Pacific warm pool is more easily destabilized eastward. These conclusions are comparable to the observed trend over the last 40 years to more regular and intense ENSO events. Future research must resolve whether global warming alone, or in concert with tectonic factors, was sufficient to alter ENSO variability during warm intervals of the Pliocene.
Comparison of FORMOSAT‐3/COSMIC radio occultation measurements with radio tomography
Authors: Thampi Smitha V. , Yamamoto Mamoru , Lin Charles , Liu Huixin
Published: May 2011

The paper reports a comparison between the continuous tomographic observations of the ionosphere during July–August 2008 and radio occultation (RO) measurements made by the Formosa Satellite 3/Constellation Observing System for Meteorology, Ionosphere, and Climate (FORMOSAT‐3/COSMIC or F3/C). The two sets of observations agree well qualitatively and bring out the main features of the low‐latitude to midlatitude ionosphere: (1) The electron density enhancements observed at ∼26°N–31°N geographic (∼16°N–21°N magnetic) latitudes during daytime are related to the equatorial ionization anomaly (EIA), and (2) the enhancements observed at night at latitudes poleward of ∼35°N geographic are related to the midlatitude summer nighttime anomaly. The comparison shows that the EIA crest densities are highly underestimated in the RO inversions that use F3/C data. It is also seen that the agreement is better in the midlatitude region, with overall features represented quite well in the RO data, highlighting its usefulness as the two techniques capture similar electron density structure, although there are some magnitude differences.
Numerical modeling of ionospheric effects in the middle‐ and low‐latitude F region during geomagnetic storm sequence of 9–14 September 2005
Authors: Klimenko M. V. , Klimenko V. V. , Ratovsky K. G. , Goncharenko L. P. , Sahai Y. , Fagundes P. R. , de Jesus R. , de Abreu A. J. , Vesnin A. M.
Published: May 2011

This study presents the Global Self‐Consistent Model of the Thermosphere, Ionosphere and Protonosphere (GSM TIP) numerical simulations of the 9–14 September 2005 geomagnetic storm effects in the middle‐ and low‐latitude ionosphere. Recent modifications to the GSM TIP model include adding an empirical model of high‐energy electron precipitation and introducing a high‐resolution (1 min) calculation of region 2 field‐aligned currents and a cross‐cap potential difference. These modifications resulted in better representation of such effects as penetration of the magnetospheric convection electric field to lower latitudes and the overshielding. The model also includes simulation of solar flare effects. Comparison of model results with observational data at Millstone Hill (42.6°N, 71.5°W, USA), Arecibo (18.3°N, 66.8°W, Puerto Rico), Jicamarca (11.9°S, 76.9°W, Peru), Palmas (10.2°S, 48.2°W, Brazil), and San Jose Campos (23.2°S, 45.9°W, Brazil) shows good agreement of ionospheric disturbances caused by this storm sequence. In this paper we consider in detail the formation mechanism of the additional layers in an equatorial ionosphere during geomagnetic storms. During geomagnetic storms, the nonuniform in height zonal electric field is generated at the geomagnetic equator. This electric field forms the additional layers in the F region of equatorial ionosphere.
Dual transcriptional profiling of a bacterial/fungal confrontation: Collimonas fungivorans versus Aspergillus niger
Authors: Mela Francesca , Fritsche Kathrin , de Boer Wietse , van Veen Johannes A , de Graaff Leo H , van den Berg Marlies , Leveau Johan H J
Published: May 2011

Interactions between bacteria and fungi cover a wide range of incentives, mechanisms and outcomes. The genus Collimonas consists of soil bacteria that are known for their antifungal activity and ability to grow at the expense of living fungi. In non-contact confrontation assays with the fungus Aspergillus niger, Collimonas fungivorans showed accumulation of biomass concomitant with inhibition of hyphal spread. Through microarray analysis of bacterial and fungal mRNA from the confrontation arena, we gained new insights into the mechanisms underlying the fungistatic effect and mycophagous phenotype of collimonads. Collimonas responded to the fungus by activating genes for the utilization of fungal-derived compounds and for production of a putative antifungal compound. In A. niger, differentially expressed genes included those involved in lipid and cell wall metabolism and cell defense, which correlated well with the hyphal deformations that were observed microscopically. Transcriptional profiles revealed distress in both partners: downregulation of ribosomal proteins and upregulation of mobile genetic elements in the bacteria and expression of endoplasmic reticulum stress and conidia-related genes in the fungus. Both partners experienced nitrogen shortage in each other's presence. Overall, our results indicate that the Collimonas/Aspergillus interaction is a complex interplay between trophism, antibiosis and competition for nutrients.
Effects of Smoking and Obesity on the Association Between CDH13 (rs3865188) and Adiponectin Among Korean Men: The KARE Study
Authors: Jo Jaeseong , Sull Jae Woong , Park Eun Jung , Jee Sun Ha
Published: May 2011

Adiponectin is secreted exclusively by adipocytes. Adiponectin is regulated by obesity, smoking, and genetic factors, including CDH13, which may contribute to development of diseases such as cardiovascular disease. Therefore, we aim to explore the joint effect of smoking and obesity on the association between CDH13 (rs3865188) and adiponectin among Korean men. This study included 1,570 Korean men aged 40–69 years who participated in the KARE cohort study (community‐based cohorts, South Korea) from 2001. Hypoadiponectinemia was defined as the lowest quartile of adiponectin. In this study, individuals with at least one at‐risk allele, the T allele, had an increased risk for hypoadiponectinemia, particularly current smokers with at least one T allele together with obesity when compared to those without the T allele. In addition, individuals with the TT genotype of CDH13 rs3865188, as well as obesity, were significantly associated with a 1.8‐fold (odds ratio (OR) = 9.4, 95% confidence interval (CI) = 4.4–19.6, P < 0.001) increased risk for hypoadiponectinemia compared to individuals with the TT genotype of CDH 13 rs3865188 and normal waist circumference (WC) (OR = 5.1, 95% CI = 3.5–7.6, P < 0.001). However, in the joint effect of smoking and obesity, current smokers with the TT genotype of CDH13 rs3865188, as well as obesity, were significantly associated with a 6.2‐fold (OR = 24.2, 95% CI = 3.0–196.6, P < 0.001) increased risk for hypoadiponectinemia compared to nonsmokers with the TT genotype of CDH 13 rs3865188 with normal WC (OR = 3.9, 95% CI = 1.7–9.3, P < 0.001). This study suggested that the association between CDH13 and adiponectin can be modified by lifestyle factors, such as smoking and obesity, among Korean men.
Tobacco Smoke Exposure Before, During, and After Pregnancy and Risk of Overweight at Age 6
Authors: Raum Elke , Küpper‐Nybelen Jutta , Lamerz Andreas , Hebebrand Johannes , Herpertz‐Dahlmann Beate , Brenner Hermann
Published: May 2011

Maternal smoking during pregnancy has been associated with overweight and obesity in childhood and is strongly correlated with children's tobacco smoke exposure before and after pregnancy. We investigated the independent association of tobacco smoke exposure at various pre‐ and postnatal periods and overweight at age 6. A total of 1,954 children attending the 2001–2002 school entrance health examination in the city of Aachen, Germany, were included into this study. Height and weight were measured, BMI was calculated. Tobacco smoke exposure at various periods, other lifestyle and sociodemographic factors were ascertained by questionnaire. Multiple logistic regression models were used to assess the association between tobacco smoke exposure and overweight. Prevalence of overweight was 8.9%. Significant positive associations were found with maternal smoking before and during pregnancy and during the first and sixth year of life. When all smoking periods were included into one logistic model simultaneously, secondhand smoke exposure after birth remained positively associated with overweight at age 6 at either one of the two time periods (first year only: odds ratio (OR) (95% confidence interval (CI)): 2.94 (1.30–6.67), sixth year only: 2.57 (1.64–4.04), respectively) or at both (4.43 (2.24–8.76)). Exposure to tobacco smoke during the first years of life appears to be a key risk factor for development of childhood overweight.
The Relationship of Birth Weight With Longitudinal Changes in Body Composition in Adult Women
Authors: Rillamas‐Sun Eileen , Sowers Mary‐Fran R. , Harlow Siobán D. , Randolph John F.
Published: May 2011

Most research on birth weight and adult health status has reported adult measures at a single time point. This study examined the relationship of self‐reported birth weight to longitudinal changes in adult body composition in 587 women of the Michigan Bone Health and Metabolism Study, followed from 1992 to 2007 and aged 24–50 years at baseline. Linear mixed models were used to estimate the association between three birth weight categories and women's 15‐year changes in adult weight, height, BMI, waist and hip circumference, waist‐to‐hip ratio, and fat, lean, and skeletal muscle mass. Body composition measures increased in all women over the 15‐year study period. At their adult baseline, high birth weight women weighed 13% more and had waist circumference and lean mass measures that were 5.51 cm and 3.91 kg larger, respectively, than normal birth weight women. No differences were observed in adult body composition between low and normal birth weight women and rates of change in the adult measures did not vary across the birth weight groups. Women heavier at birth continued to be heavier through adulthood, corroborating previous reports based on single measures of adult body composition. Research to address whether higher adult body composition in high birth weight women increases the longitudinal risk for obesity‐related chronic diseases is needed.
Diagnosing and controlling mix in National Ignition Facility implosion experiments
Authors: Hammel B. A. , Scott H. A. , Regan S. P. , Cerjan C. , Clark D. S. , Edwards M. J. , Epstein R. , Glenzer S. H. , Haan S. W. , Izumi N. , Koch J. A. , Kyrala G. A. , Landen O. L. , Langer S. H. , Peterson K. , Smalyuk V. A. , Suter L. J. , Wilson D. C.
Published: May 2011

High mode number instability growth of “isolated defects” on the surfaces of National Ignition Facility [Moses et al., Phys. Plasmas 16, 041006 (2009)] capsules can be large enough for the perturbation to penetrate the imploding shell, and produce a jet of ablator material that enters the hot-spot. Since internal regions of the CH ablator are doped with Ge, mixing of this material into the hot-spot results in a clear signature of Ge K-shell emission. Evidence of jets entering the hot-spot has been recorded in x-ray images and spectra, consistent with simulation predictions [Hammel et al., High Energy Density Phys. 6, 171 (2010)]. Ignition targets have been designed to minimize instability growth, and capsule fabrication improvements are underway to reduce “isolated defects.” An experimental strategy has been developed where the final requirements for ignition targets can be adjusted through direct measurements of mix and experimental tuning.
Stimulated Raman scatter analyses of experiments conducted at the National Ignition Facility
Authors: Hinkel D. E. , Rosen M. D. , Williams E. A. , Langdon A. B. , Still C. H. , Callahan D. A. , Moody J. D. , Michel P. A. , Town R. P. J. , London R. A. , Langer S. H.
Published: May 2011

Recent experiments conducted at the National Ignition Facility achieved two main goals: providing radiation drive and symmetry suitable for subsequent ignition experiments. Of the many diagnostics fielded, one provided a time-resolved wavelength spectrum of light reflected from the target by stimulated Raman scatter (SRS). SRS occurs when incident light reflects off self-generated electron plasma waves. Analyses indicate that synthetic SRS spectra better match those of experiments when an atomic physics model with greater emissivity is utilized in target modeling, along with less inhibited electron transport (higher flux, with, ideally, nonlocal electron transport). With these models, SRS occurs in a target region where nearest-neighbor quads of laser beams significantly overlap the diagnosed quad. This increases SRS gain at lower density (lower wavelength), a feature consistent with experimental results. Inclusion of this effect of multiple quads sharing a reflected SRS light wave has resulted in improved capabilities used to successfully predict (preshot) the SRS spectrum from the first target driven with 1.25 MJ of laser energy. Additional resonant amplification of SRS light in the overlap intensity region is demonstrated in beam propagation simulations. Such effects will be reduced in a target optimized for these less dense and cooler plasma conditions.
Geometric invariance of mass-like asymptotic invariants
Authors: Michel B.
Published: May 2011

We study coordinate-invariance of some asymptotic invariants, such as the Arnowitt-Deser-Misner mass or the Chruściel–Herzlich momentum, given by an integral over a “boundary at infinity.” When changing the coordinates at infinity, some terms in the change of integrand do not decay fast enough to have a vanishing integral at infinity; but they may be gathered in a divergence, thus having vanishing integral over any closed hypersurface. This fact could only be checked after direct calculation (and was called a “curious cancellation”). We give a conceptual explanation thereof.
Coulomb divergence of the high-frequency expansion of the dielectric permittivity
Authors: Bobrov V. B. , Mendeleyev V. Ya. , Skovorod’ko S. N. , Trigger S. A.
Published: May 2011

Based on accurate results of the linear response theory and the Kramers-Kronig relations, the permittivity ɛ(ω) of the non-relativistic Coulomb system is analyzed at arbitrary thermodynamic parameters in the high-frequency limit ω→∞. It is shown that the expansion of the real part of the permittivity Reɛ(ω) in powers of 1/ω2 is limited to only three terms. Limit constraints on the power-law behavior of the imaginary part of the permittivity Imɛ(ω) are determined.
Experimental and theoretical study of polarization-dependent optical transitions in InAs quantum dots at telecommunication-wavelengths (1300-1500 nm)
Authors: Usman Muhammad , Heck Susannah , Clarke Edmund , Spencer Peter , Ryu Hoon , Murray Ray , Klimeck Gerhard
Published: May 2011

The design of some optical devices, such as semiconductor optical amplifiers for telecommunication applications, requires polarization-insensitive optical emission at long wavelengths (1300–1550 nm). Self-assembled InAs/GaAs quantum dots (QDs) typically exhibit ground state optical emissions at wavelengths shorter than 1300 nm with highly polarization-sensitive characteristics, although this can be modified by the use of low growth rates, the incorporation of strain-reducing capping layers, or the growth of closely-stacked QD layers. Exploiting the strain interactions between closely stacked QD layers also affords greater freedom in the choice of growth conditions for the upper layers, so that both a significant extension in their emission wavelength and an improved polarization response can be achieved due to modification of the QD size, strain, and composition. In this paper, we investigate the polarization behavior of single and stacked QD layers using room temperature sub-lasing-threshold electroluminescence and photovoltage measurements, as well as atomistic modeling with the NEMO 3-D simulator. A reduction is observed in the ratio of the transverse electric (TE) to transverse magnetic (TM) optical mode response for a GaAs-capped QD stack as compared to a single QD layer, but when the second layer of the two-layer stack is InGaAs-capped, an increase in the TE/TM ratio is observed, in contrast to recent reports for single QD layers.
Fourth-order relativistic corrections to electrical first-order properties using direct perturbation theory
Authors: Stopkowicz Stella , Gauss Jürgen
Published: May 2011

In this work, we present relativistic corrections to first-order electrical properties obtained using fourth-order direct perturbation theory (DPT4) at the Hartree-Fock level. The considered properties, i.e., dipole moments and electrical-field gradients, have been calculated using numerical differentiation techniques based on a recently reported DPT4 code for energies [S. Stopkowicz and J. Gauss, J. Chem. Phys. 134, 064114 (2011)]10.1063/1.3522766. For the hydrogen halides HX, X=F, Cl, Br, I, and At, we study the convergence of the scalar-relativistic contributions by comparing the computed DPT corrections to results from spin-free Dirac-Hartree-Fock calculations. Furthermore, since in the DPT series spin-orbit contributions first appear at fourth order, we investigate their magnitude and judge the performance of the DPT4 treatment by means of Dirac-Hartree-Fock benchmark calculations. Finally, motivated by experimental investigations of the molecules CH2FBr, CHF2Br, and CH2FI, we present theoretical results for their halogen quadrupole-coupling tensors and give recommendations concerning the importance of higher-order scalar-relativistic and spin-orbit corrections.
The pinch of cold ions from recycling in the tokamak edge pedestal
Authors: Wan Weigang , Parker Scott E. , Chen Yang , Park Gun-Young , Chang Choong-Seock , Stotler Daren
Published: May 2011

We apply the “natural fueling mechanism” [W. Wan, S. E. Parker, Y. Chen, and F. W. Perkins, Phys. Plasmas 17, 040701 (2010)] to the edge pedestal. The natural fueling mechanism is where cold ions naturally pinch radially inward for a heat-flux dominated plasma. It is shown from neoclassical-neutral transport coupled simulations that the recycling neutrals and the associated source ions are colder than the main ions in the edge pedestal. These recycling source ions will pinch radially inward due to microturbulence. Gyrokinetic turbulence simulations indicate that near the top of the pedestal, the pinch velocity of the recycling source ions is much higher than the main ion outgoing flow velocity. The turbulent pinch of the recycling source ions may play a role in the edge pedestal transport and dynamics. The cold ion temperature significantly enhances the pinch velocity of the recycling source ions near to the pedestal top. Neoclassical calculations show a cold ion pinch in the pedestal as well.
Micromirror arrays to assess luminescent nano-objects
Authors: Kawakami Yoichi , Kanai Akinobu , Kaneta Akio , Funato Mitsuru , Kikuchi Akihiko , Kishino Katsumi
Published: May 2011

We propose an array of submicrometer mirrors to assess luminescent nano-objects. Micromirror arrays (MMAs) are fabricated on Si (001) wafers via selectively doping Ga using the focused ion beam technique to form p-type etch stop regions, subsequent anisotropic chemical etching, and Al deposition. MMAs provide two benefits: reflection of luminescence from nano-objects within MMAs toward the Si (001) surface normal and nano-object labeling. The former increases the probability of optics collecting luminescence and is demonstrated by simulations based on the ray-tracing and finite-difference time-domain methods as well as by experiments. The latter enables different measurements to be repeatedly performed on a single nano-object located at a certain micromirror. For example, a single InGaN/GaN nanocolumn is assessed by scanning electron microscopy and microphotoluminescence spectroscopy.
Tomographic reconstruction of incompressible flow
Authors: Nemirovsky Jonathan , Lifshitz Asaf , Be'ery Ilan
Published: May 2011

In many experiments facilitating tomography the reconstruction problem is under-determined, meaning there are many possible solutions consistent with the measurements. If the sampling rate is fast relative to the typical evolution time, the known physical dynamics of the system can be used as additional reconstruction constraints. Here we demonstrate that incorporating the requirement of incompressible flow can improve significantly the fidelity of the reconstructed sequence. The incompressibility of the reconstruction is assured by requiring the conservation of the density moments. It is demonstrated that the “incompressible” reconstruction can be significantly more accurate than the reconstruction using standard methods. A consequence of the density moments’ conservation is the conservation of the density histogram throughout the reconstructed sequence.
Pseudospin symmetry for a new oscillatory ring-shaped noncentral potential
Authors: Zhang Min-Cang , Huang-Fu Guo-Qing
Published: May 2011

A new oscillatory ring-shaped noncentral potential is proposed and the pseudospin symmetry for this potential is investigated by solving the Dirac equation with equally mixed scalar and vector potentials with opposite signs. The spinor wave functions and the energy spectrum for the bound states are obtained by using the Nikiforov-Uvarov method. The effect of angle-dependent part on the radial solutions and the algebraic property of the energy equation are discussed.
Foreword to Special Issue: Papers from the 52nd Annual Meeting of the APS Division of Plasma Physics, Chicago, Illinois, USA, 2010
Authors: Allen Steve L. , Davidson Ronald C.
Published: May 2011

We present in this Special Issue of Physics of Plasmas the review, tutorial, and invited papers of the 2010 Annual Meeting of the American Physical Society’s (APS) Division of Plasma Physics. This was the 52nd year of this meeting, and it was held in Chicago, Illinois on 8–12 November 2010. The meeting program was made up of over 100 review, tutorial, and invited oral presentations, and a significant fraction of these speakers prepared manuscripts which were peer-reviewed and are contained in this Special Issue.
Edge transport and turbulence reduction with lithium coated plasma facing components in the National Spherical Torus Experiment
Authors: Canik J. M. , Maingi R. , Kubota S. , Ren Y. , Bell R. E. , Callen J. D. , Guttenfelder W. , Kugel H. W. , LeBlanc B. P. , Osborne T. H. , Soukhanovskii V. A.
Published: May 2011

The coating of plasma facing components (PFCs) with lithium improves energy confinement and eliminates ELMs in the National Spherical Torus Experiment, the latter due to a relaxation of the density and pressure profiles that reduces the drive for peeling-ballooning modes. 2-D interpretive transport modeling of discharges without and with lithium shows that a reduction in the PFC recycling coefficient from R ∼ 0.98 to R ∼ 0.90 is required to match the drop in Dα emission with lithium coatings. A broadening of the edge barrier region showing reduced transport coefficients is observed, with a ∼75% drop of the D and χe from 0.8 < ψN < 0.93 needed to match the profile relaxation with lithium coatings. Turbulence measurements using an edge reflectometry system as well as high-k microwave scattering show a decrease in density fluctuations with lithium coatings. These transport changes allow the realization of very wide pedestals, with a ∼100% width increase relative to the reference discharges.
Glassy dynamics and mechanical response in dense fluids of soft repulsive spheres. II. Shear modulus, relaxation-elasticity connections, and rheology
Authors: Yang Jian , Schweizer Kenneth S.
Published: May 2011

We apply the quiescent and mechanically driven versions of nonlinear Langevin equation theory to study how particle softness influences the shear modulus, the connection between shear elasticity and activated relaxation, and nonlinear rheology of the repulsive Hertzian contact model of dense soft sphere fluids. Below the soft jamming threshold, the shear modulus follows a power law dependence on volume fraction over a narrow interval with an apparent exponent that grows with particle stiffness. To a first approximation, the elastic modulus and transient localization length are controlled by a single coupling constant determined by local fluid structure. In contrast to the behavior of hard spheres, an approximately linear relation between the shear modulus and activation barrier is predicted. This connection has recently been observed for microgel suspensions and provides a microscopic realization of the elastic shoving model. Yielding, shear and stress thinning of the alpha relaxation time and viscosity, and flow curves are also studied. Yield strains are relatively weakly dependent on volume fraction and particle stiffness. Shear thinning commences at values of the effective Peclet number far less than unity, a signature of stress-assisted activated relaxation when barriers are high. Apparent power law reduction of the viscosity with shear rate is predicted with a thinning exponent less than unity. In the vicinity of the soft jamming threshold, a power law flow curve occurs over an intermediate reduced shear rate range with an apparent exponent that decreases as fluid volume fraction and/or repulsion strength increase.
Antenna-based ultrahigh vacuum microwave frequency scanning tunneling microscopy system
Authors: Giridharagopal Rajiv , Zhang Jun , Kelly Kevin F.
Published: May 2011

The instrumental synthesis of high resolution scanning tunneling microscopy (STM) with the ability to measure differential capacitance with atomic scale resolution is highly desirable for fundamental metrology and for the study of novel physical characteristics. Microwave frequency radiation directed at the tip-sample junction in an STM system allows for such high-resolution differential capacitance information. This ability is particularly critical in ultrahigh vacuum environments, where the additional parameter space afforded by including a capacitance measurement would prove powerful. Here we describe the modifications made to a commercial scanning tunneling microscope to allow for broad microwave frequency alternating current scanning tunneling microscopy (ACSTM) in ultrahigh vacuum conditions using a relatively simple loop antenna and microwave difference frequency detection. The advantages of our system are twofold. First, the use of a removable antenna on a commercial STM prevents interference with other UHV processes while providing a simple method to retrofit any commercial UHV-STM with UHV-ACSTM capability. Second, mounting the microwave antenna on a translator allows for specific tuning of the system to replicate experimental conditions between samples, which is particularly critical in sensitive systems like organic thin films or single molecules where small changes in incident power can affect the results. Our innovation therefore provides a valuable approach to give nearly any commercial STM, be it an ambient or UHV system, the capability to measure atomic-scale microwave studies such as differential capacitance or even single molecule microwave response, and it ensures that experimental ACSTM conditions can be held constant between different samples.
A powerful computational crystallography method to study ice polymorphism
Authors: Cogoni M. , D'Aguanno B. , Kuleshova L. N. , Hofmann D. W. M.
Published: May 2011

Classical molecular dynamics (MD) simulations are employed as a tool to investigate structural properties of ice crystals under several temperature and pressure conditions. All ice crystal phases are analyzed by means of a computational protocol based on a clustering approach following standard MD simulations. The MD simulations are performed by using a recently published classical interaction potential for oxygen and hydrogen in bulk water, derived from neutron scattering data, able to successfully describe complex phenomena such as proton hopping and bond formation/breaking. The present study demonstrates the ability of the interaction potential model to well describe most ice structures found in the phase diagram of water and to estimate the relative stability of 16 known phases through a cluster analysis of simulated powder diagrams of polymorphs obtained from MD simulations. The proposed computational protocol is suited for automated crystal structure identification.
Nuclear motion on the orbitally degenerate electronic ground state of fully deuterated triatomic hydrogen
Authors: Rao T. Rajagopala , Mahapatra S.
Published: May 2011

Nuclear motion in the vicinity of conical intersections of the degenerate electronic ground state of fully deuterated triatomic hydrogen, D3, is investigated with the aid of a time-dependent wavepacket approach in hyperspherical coordinates. Vibronic energy level spectra and the eigenfunctions are examined by including, for example, (1) geometric phase (GP) correction, (2) diagonal Born-Huang (BH) correction, and (3) both GP and BH corrections to the Born-Oppenheimer adiabatic Hamiltonian and finally by considering the nonadiabatic coupling between the two electronic surfaces explicitly. It emerges from this study that inclusion of both the GP and BH corrections is insufficient to explain the spectral features observed in the experiment. The latter are recovered by considering the complete two-states coupled Hamiltonian only. This study shows that both the GP and BH corrections constitute a minor part of the surface coupling effects, in particular, on the dynamics of the upper adiabatic sheet. Most importantly, we add that the experimental signature of the GP effect appears only in the observed shift of the eigenlevels of the electronic state when compared to those obtained from a completely Born-Oppenheimer Hamiltonian. The detail fine structure of the observed band of the electronic state is shaped by the off-diagonal derivative coupling elements of the nonadiabatic coupling operator.