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Over the last several years, a new generation of quantum simulations has greatly expanded our understanding of charge density wave phase transitions in Hamiltonians with coupling between local phonon modes and the on-site charge density. A quite different, and interesting, case is one in which the phonons live on the bonds, and hence modulate the electron hopping. This situation, described by the Su-Schrieffer-Heeger (SSH) Hamiltonian, has so far only been studied with quantum Monte Carlo in one dimension. Here we present results for the 2D SSH model, and show that a bond ordered wave (BOW) insulator is present in the ground state at half-filling, and argue that a critical value of the electron-phonon coupling is required for its onset, in contradistinction with the 1D case where BOW exists for any nonzero coupling. We determine the precise nature of the bond ordering pattern, which has hitherto been controversial, and the critical transition temperature, which is associated with a spontaneous breaking of ${\cal Z}_4$ symmetry., 5 pages, 7 figures

Using the satellite structure of the $L_{\gamma1}$ line in non-resonant x-ray emission spectra, we probe the high-pressure evolution of the bare 4f signature of the early light lanthanides at ambient temperature. For Ce and Pr the satellite peak experiences a sudden reduction concurrent with their respective volume collapse (VC) transitions. These new experimental results are supported by calculations using state-of-the-art extended atomic structure codes for Ce and Pr, and also for Nd, which does not exhibit a VC. Our work suggests that changes to the 4f occupation are more consistently associated with evolution of the satellite than is the reduction of the 4f moment. Indeed, we show that in the case of Ce, mixing of a higher atomic angular momentum state, driven by the increased hybridization, acts to obscure the expected satellite reduction. These measurements emphasize the importance of a unified study of a full set of microscopic observables to obtain the most discerning test of the underlying, fundamental f-electron phenomena at high pressures., Comment: 9 pages, 4 figures

The effect of electron-electron interactions on Dirac fermions, and the possibility of an intervening spin liquid phase between the semi-metal and antiferromagnetic (AF) regimes, has been a focus of intense quantum simulation effort over the last five years. We use determinant quantum Monte Carlo (DQMC) to study the Holstein model on a Honeycomb lattice and explore the role of electron-phonon interactions on Dirac fermions. We show that they give rise to charge density wave (CDW) order, and present evidence that this occurs only above a finite critical interaction strength. We evaluate the temperature for the transition into the CDW which, unlike the AF transition, can occur at finite values owing to the discrete nature of the broken symmetry., Comment: 9 pages, 9 figures

The Holstein Model (HM) describes the interaction between fermions and a collection of local (dispersionless) phonon modes. In the dilute limit, the phonon degrees of freedom dress the fermions, giving rise to polaron and bipolaron formation. At higher densities, the phonons mediate collective superconducting (SC) and charge density wave (CDW) phases. Quantum Monte Carlo (QMC) simulations have considered both these limits, but have not yet focused on the physics of more general phonon spectra. Here we report QMC studies of the role of phonon dispersion on SC and CDW order in such models. We quantify the effect of finite phonon bandwidth and curvature on the critical temperature $T_{\rm cdw}$ for CDW order, and also uncover several novel features of diagonal long range order in the phase diagram, including a competition between charge patterns at momenta ${\bf q}=(\pi,\pi)$ and ${\bf q}=(0,\pi)$ which lends insight into the relationship between Fermi surface nesting and the wavevector at which charge order occurs. We also demonstrate SC order at half-filling in situations where nonzero bandwidth sufficiently suppresses $T_{\rm cdw}$., Comment: 6 Figs + Supplemental Material

BackgroundThe U.S. Army uses universal preventives interventions for several negative outcomes (e.g. suicide, violence, sexual assault) with especially high risks in the early years of service. More intensive interventions exist, but would be cost-effective only if targeted at high-risk soldiers. We report results of efforts to develop models for such targeting from self-report surveys administered at the beginning of Army service.Methods21 832 new soldiers completed a self-administered questionnaire (SAQ) in 2011–2012 and consented to link administrative data to SAQ responses. Penalized regression models were developed for 12 administratively-recorded outcomes occurring by December 2013: suicide attempt, mental hospitalization, positive drug test, traumatic brain injury (TBI), other severe injury, several types of violence perpetration and victimization, demotion, and attrition.ResultsThe best-performing models were for TBI (AUC = 0.80), major physical violence perpetration (AUC = 0.78), sexual assault perpetration (AUC = 0.78), and suicide attempt (AUC = 0.74). Although predicted risk scores were significantly correlated across outcomes, prediction was not improved by including risk scores for other outcomes in models. Of particular note: 40.5% of suicide attempts occurred among the 10% of new soldiers with highest predicted risk, 57.2% of male sexual assault perpetrations among the 15% with highest predicted risk, and 35.5% of female sexual assault victimizations among the 10% with highest predicted risk.ConclusionsData collected at the beginning of service in self-report surveys could be used to develop risk models that define small proportions of new soldiers accounting for high proportions of negative outcomes over the first few years of service.

We theoretically study the orbital diamagnetic response of three-dimensional arrays of embedded InAs/GaAs wobbled nano-rings. To simulate the rings' magnetic characteristics, we use the effective one band Hamiltonian (energy and position-dependent electron effective mass and Lande factor) and smooth three-dimensional confinement potential that is mapping the actual strain and material content inside the rings. First, we obtain the magnetic susceptibility of an individual nano-ring. Once it is achieved, using the Claussius–Mossotti relation we estimate the effective susceptibility of three-dimensional arrays of the rings. We show that conventionally diamagnetic InAs/GaAs ring structures under certain conditions can demonstrate the positive peak of the effective magnetic susceptibility of the arrays, that we call “negative”-diamagnetic response. The “negative”-diamagnetic (positive susceptibility) peak remains Lorentz-like shaped and gradually disappears when the rings' concentration in the arrays decreases.

BackgroundSuicide is a leading cause of death worldwide; however, little information is available about the treatment of suicidal people, or about barriers to treatment.AimsTo examine the receipt of mental health treatment and barriers to care among suicidal people around the world.MethodTwenty-one nationally representative samples worldwide (n=55 302; age 18 years and over) from the World Health Organization's World Mental Health Surveys were interviewed regarding past-year suicidal behaviour and past-year healthcare use. Suicidal respondents who had not used services in the past year were asked why they had not sought care.ResultsTwo-fifths of the suicidal respondents had received treatment (from 17% in low-income countries to 56% in high-income countries), mostly from a general medical practitioner (22%), psychiatrist (15%) or non-psychiatrist (15%). Those who had actually attempted suicide were more likely to receive care. Low perceived need was the most important reason for not seeking help (58%), followed by attitudinal barriers such as the wish to handle the problem alone (40%) and structural barriers such as financial concerns (15%). Only 7% of respondents endorsed stigma as a reason for not seeking treatment.ConclusionsMost people with suicide ideation, plans and attempts receive no treatment. This is a consistent and pervasive finding, especially in low-income countries. Improving the receipt of treatment worldwide will have to take into account culture-specific factors that may influence the process of help-seeking.

As there appeared to be no data available on Toxocara canis infection in the children of Swaziland, a serological survey of T. canis infection was recently conducted among 92 children aged 3-12 years from rural slums in the low- and middle-veld. A child was considered seropositive if, in western blots based on the excretory-secretory antigens of larval T. canis, his or her serum gave a positive result when diluted 1 : 64. Forty-one (44.6%) of the children were found seropositive. There were no statistically significant differences in seroprevalence between the 49 boys and 43 girls investigated (46.9% v. 41.8%) or between the eight subjects aged 12 years and the 47 aged < or = 5 years (62.5% v. 38.3%); the corresponding odds ratios were 0.81 (95% confidence interval=0.36-1.86; P=0.62) and 2.69 (95% confidence interval=0.57-12.62; P=0.20), respectively. The 66 subjects from the middleveld were, however, significantly more likely to be seropositive than the 26 subjects from the lowveld (54.5% v. 19.2%; odds ratio=5.04, with a 95% confidence interval of 1.70-14.98; P

BackgroundThe ‘gateway’ pattern of drug initiation describes a normative sequence, beginning with alcohol and tobacco use, followed by cannabis, then other illicit drugs. Previous work has suggested that ‘violations’ of this sequence may be predictors of later problems but other determinants were not considered. We have examined the role of pre-existing mental disorders and sociodemographics in explaining the predictive effects of violations using data from the US National Comorbidity Survey Replication (NCS-R).MethodThe NCS-R is a nationally representative face-to-face household survey of 9282 English-speaking respondents aged 18 years and older that used the World Health Organization (WHO) Composite International Diagnostic Interview (CIDI) to assess DSM-IV mental and substance disorders. Drug initiation was estimated using retrospective age-of-onset reports and ‘violations’ defined as inconsistent with the normative initiation order. Predictors of violations were examined using multivariable logistic regressions. Discrete-time survival analysis was used to see whether violations predicted progression to dependence.ResultsGateway violations were largely unrelated to later dependence risk, with the exception of small increases in risk of alcohol and other illicit drug dependence for those who initiated use of other illicit drugs before cannabis. Early-onset internalizing disorders were predictors of gateway violations, and both internalizing and externalizing disorders increased the risks of dependence among users of all drugs.ConclusionsDrug use initiation follows a strong normative pattern, deviations from which are not strongly predictive of later problems. By contrast, adolescents who have already developed mental health problems are at risk for deviations from the normative sequence of drug initiation and for the development of dependence.

The Periodic Anderson Model (PAM) is widely studied to understand strong correlation physics and especially the competition of antiferromagnetism and singlet formation. Quantum Monte Carlo (QMC) studies have focused both on issues such as the nature of screening and locating the quantum critical point (QCP) at zero temperature and also on possible experimental connections to phenomena ranging from the Cerium volume collapse to the relation of the magnetic susceptibility and Knight shift in heavy fermions. In this paper we extend QMC work to lattices in which the conduction electron sites can have variable coordination. This situation is relevant both to recently discovered magnetic quasicrystals and also to magnetism in doped heavy fermion systems., 8 pages, 10 figures

We simulate magneto-excitons confined in asymmetrically wobbled three-dimensional InAs/GaAs nano-rings. The wobbling asymmetry reproduces realistic experimental geometry of the rings and generates an asymmetry in the side valleys of the three dimensional confinement potential. Using our mapping method and the exact diagonization approach we calculated the excitonic diamagnetic shift and found that even a small wobbling asymmetry can drastically change the diamagnetic shift coefficient. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The goal of this study is to examine the influence of education and recovery status on substance abuse treatment counselors' approach to patients. Three hundred forty-four drug abuse and alcoholism treatment counselors were questioned about treatment goals. A subgroup of 197 were also questioned about treatment practices. The influences of education and recovery status on the choice of treatment goals and treatment practices were examined through structural modeling procedures. Level of education influenced neither treatment goals nor techniques. Being in recovery, however, was associated with more varied treatment techniques and a broader range of treatment goals. The other variable related to treatment goals and practices was treatment modality. Working in resi dential programs was linked to a wider range of treatment goals and treatment practices. Implications of these findings for counselor training and the movement to professionalize substance abuse treatment are discussed.

Portfolio assessment has become a popular medium for merging classroom assessment with large-scale testing, but adoption of portfolios in the classroom for external assessment purposes may be difficult because the use of such portfolios may require changes in the curriculum, instructions, and assessments used by teachers. As a result, there are numerous potential barriers to the adoption of portfolios that can be used for large-scale assessment purposes. This study investigates how secondary teachers' perceptions of portfolio implementation barriers changed when teachers participated in a 1-year portfolio implementation effort. Survey results are analyzed with a Rasch rating scale model. Results suggest that teachers' apprehension about portfolio barriers increased slightly, but that this increase can be attributable to teachers with little portfolio experience. Furthermore, teachers' concerns about the amount of time required to develop and score portfolios increased substantially while concerns about the availability of resources and resistance from parents decreased.

In this paper a theoretical study was made of the conditional averages of the magnetization and magnetic susceptibility of dispersive ensembles of nano-objects with a very complex geometry---self-assembled wobbled semiconductor quantum rings. Using the multivariate statistics approach and previously proposed mapping method the impact of the dispersion of the ring geometry parameters on the static magnetic response of the ensembles has been investigated near the first Aharonov-Bohm oscillation. The description is suited to clarify the important question of which geometrical parameters' dispersions are crucial for the formation and properties of the magnetic response of ensembles. We theoretically show that for the dispersive ensembles of InGaAs/GaAs capped wobbled quantum rings the actual value and temperature dependence of the differential magnetic susceptibility can be optimized by an appropriate control of the conditional parameters of the ensembles. The ring rim radius variations play a crucial role in this dependence. We have managed to simulate in detail the temperature behavior of the meaningful averages of the magnetization and positive peak of the differential magnetic susceptibility for ensembles of the rings known from the experiment. The simulated temperature dependence, position, and magnitude of the positive peak in the differential magnetic susceptibility are in a good agreement with the experimental observations.

Enterohaemorrhagic Escherichia coli (EHEC) causes life-threatening infections in humans as a consequence of the production of Shiga-like toxins. Lack of a good animal model system currently hinders in vivo study of EHEC virulence by systematic genetic methods. Here we applied the genetically tractable animal, Caenorhabditis elegans, as a surrogate host to study the virulence of EHEC as well as the host immunity to this human pathogen. Our results show that E. coli O157:H7, a serotype of EHEC, infects and kills C. elegans. Bacterial colonization and induction of the characteristic attaching and effacing (A/E) lesions in the intact intestinal epithelium of C. elegans by E. coli O157:H7 were concomitantly demonstrated in vivo. Genetic analysis indicated that the Shiga-like toxin 1 (Stx1) of E. coli O157:H7 is a virulence factor in C. elegans and is required for full toxicity. Moreover, the C. elegans p38 mitogen-activated protein kinase (MAPK) pathway, an evolutionarily conserved innate immune and stress response signalling pathway, is activated in the regulation of host susceptibility to EHEC infection in a Stx1-dependent manner. Our results validate the EHEC-C. elegans interaction as suitable for future comprehensive genetic screens for both novel bacterial and host factors involved in the pathogenesis of EHEC infection.

Previous research suggests that parental psychopathology predicts suicidal behavior among offspring; however, the more fine-grained associations between specific parental disorders and distinct stages of the pathway to suicide are not well understood. We set out to test the hypothesis that parental disorders associated with negative mood would predict offspring suicide ideation, whereas disorders characterized by impulsive aggression (for example, antisocial personality) and anxiety/agitation (for example, panic disorder) would predict which offspring act on their suicide ideation and make a suicide attempt. Data were collected during face-to-face interviews conducted on nationally representative samples (N=55 299; age 18+) from 21 countries around the world. We tested the associations between a range of parental disorders and the onset and persistence over time (that is, time since most recent episode controlling for age of onset and time since onset) of subsequent suicidal behavior (suicide ideation, plans and attempts) among offspring. Analyses tested bivariate and multivariate associations between each parental disorder and distinct forms of suicidal behavior. Results revealed that each parental disorder examined increased the risk of suicide ideation among offspring, parental generalized anxiety and depression emerged as the only predictors of the onset and persistence (respectively) of suicide plans among offspring with ideation, whereas parental antisocial personality and anxiety disorders emerged as the only predictors of the onset and persistence of suicide attempts among ideators. A dose-response relation between parental disorders and respondent risk of suicide ideation and attempt was also found. Parental death by suicide was a particularly strong predictor of persistence of suicide attempts among offspring. These associations remained significant after controlling for comorbidity of parental disorders and for the presence of mental disorders among offspring. These findings should inform future explorations of the mechanisms of intergenerational transmission of suicidal behavior. These activities were supported by the United States National Institute of Mental Health (R01MH070884, R01MH077883), the John D. and Catherine T. MacArthur Foundation, the Pfizer Foundation, the US Public Health Service (R13-MH066849, R01-MH069864, and R01 DA016558), the Fogarty International Center (FIRCA R03-TW006481). The São Paulo Megacity Mental Health Survey is supported by the State of São Paulo Research Foundation (FAPESP) Thematic Project Grant 03/00204-3. The ESEMeD project is funded by the European Commission (Contracts QLG5-1999-01042; SANCO 2004123), the Piedmont Region (Italy), Fondo de Investigación Sanitaria, Instituto de Salud Carlos III, Spain (FIS 00/0028), Ministerio de Ciencia y Tecnología, Spain (SAF 2000-158-CE), Departament de Salut, Generalitat de Catalunya, Spain, Instituto de Salud Carlos III (CIBER CB06/02/0046, RETICS RD06/0011 REM-TAP). The World Mental Health Japan (WMHJ) Survey is supported by the Grant for Research on Psychiatric and Neurological Diseases and Mental Health (H13-SHOGAI-023, H14-TOKUBETSU-026, H16-KOKORO-013) from the Japan Ministry of Health, Labour and Welfare. The Mexican National Comorbidity Survey (MNCS) is supported by The National Institute of Psychiatry Ramon de la Fuente (INPRFMDIES 4280) and by the National Council on Science and Technology (CONACyT-G30544- H). The South Africa Stress and Health Study (SASH) is supported by the US National Institute of Mental Health (R01-MH059575). The Ukraine Comorbid Mental Disorders during Periods of Social Disruption (CMDPSD) study is funded by the US National Institute of Mental Health (RO1-MH61905). The US National Comorbidity Survey Replication (NCS-R) is supported by the National Institute of Mental Health (NIMH; U01-MH60220) with supplemental support from the Robert Wood Johnson Foundation (RWJF; Grant 044708).

We carried out a parasitological survey of Schistosoma haematobium infection among the residents of Lowveld Siphofaneni, Swaziland, an area which is devoid of sanitation. Subjects with positive infection were confirmed by the detection of S. haematobium ova in their urine. The intensity of the infection was estimated by calculating the total number of S. haematobium ova present in 10 ml urine specimen (geometric mean intensity; GMI). Overall, the prevalence of S. haematobium infection was 6.1% (18/295) with a GMI of 20.7 (95% CI=9.1~32.2). Female (10.5%, 16/153) had significantly higher prevalence than that in male (1.4%, 2/142) (ORs=8.2, 95% CI=1.8- 36.2, P0.01); conversely, male had higher GMI (60.0) than that (17.3) in female. The age group of ≤5 yrs (15.3%, 9/59) had significantly higher prevalence than that in age group of ≥19 yrs (2.6%, 3/115) (ORs=0.2, 95% CI=0.04-0.57, P0.01). The highest GMI of 27.9 (95% CI=7.6~48.2) was also seen in age group of ≤5 yrs.

To investigate the association of a range of temporally prior physical conditions with the subsequent first onset of suicidal ideation, plans, and attempts in large, general population, cross-national sample. The associations between physical conditions and suicidal behavior remain unclear due to sparse data and varied methodology.Predictive associations between 13 temporally prior physical conditions and first onset of suicidal ideation, plans, and attempts were examined in a 14-country sample (n = 37,915) after controlling for demographic, socioeconomic, and psychosocial covariates, with and without adjustment for mental disorders.Most physical conditions were associated with suicidal ideation in the total sample; high blood pressure, heart attack/stroke, arthritis, chronic headache, other chronic pain, and respiratory conditions were associated with attempts in the total sample; epilepsy, cancer, and heart attack/stroke were associated with planned attempts. Epilepsy was the physical condition most strongly associated with the suicidal outcomes. Physical conditions were especially predictive of suicidality if they occurred early in life. As the number of physical conditions increased, the risk of suicidal outcomes also increased, however the added risk conferred was generally smaller with each additional condition. Adjustment for mental disorders made little substantive difference to these results. Physical conditions were equally predictive of suicidality in higher and lower income countries.The presence of physical conditions is a risk factor for suicidal behavior even in the absence of mental disorder.

As there appeared to be no data available on Toxocara canis infection in the children of Swaziland, a serological survey of T. canis infection was recently conducted among 92 children aged 3-12 years from rural slums in the low- and middle-veld. A child was considered seropositive if, in western blots based on the excretory-secretory antigens of larval T. canis, his or her serum gave a positive result when diluted 1 : 64. Forty-one (44.6%) of the children were found seropositive. There were no statistically significant differences in seroprevalence between the 49 boys and 43 girls investigated (46.9% v. 41.8%) or between the eight subjects aged 12 years and the 47 agedor = 5 years (62.5% v. 38.3%); the corresponding odds ratios were 0.81 (95% confidence interval=0.36-1.86; P=0.62) and 2.69 (95% confidence interval=0.57-12.62; P=0.20), respectively. The 66 subjects from the middleveld were, however, significantly more likely to be seropositive than the 26 subjects from the lowveld (54.5% v. 19.2%; odds ratio=5.04, with a 95% confidence interval of 1.70-14.98; P0.01). It seems likely that T. canis infection is common among the children who live in slums in Swaziland, particularly in the country's middleveld, probably as the result of poor hygiene and poor sanitation.

Background Although much is known about risk factors for the initiation of alcohol use, abuse, and dependence, few population-based studies have examined the predictors of transitions across these stages. Aim The aim of this study is to examine the sociodemographic predictors of transitions across 6 stages of alcohol use in the National Comorbidity Survey Replication, a nationally representative household survey of the US population. Methods A lifetime history of alcohol use, regular use (at least 12 drinks in a year), Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition alcohol abuse and dependence with abuse was collected in 5692 National Comorbidity Survey Replication respondents using the World Health Organization Composite International Diagnostic Interview, Version 3.0. Results Lifetime prevalence estimates were 91.7% for lifetime alcohol use, 72.9% for regular use, 13.2% for abuse, and 5.4% for dependence with abuse. Male sex, young age, non-Hispanic white race/ethnicity, low education, student status, and never being married predicted the onset of alcohol use, the transition from use to regular use, and from regular use to abuse. An early age of onset of alcohol use also predicted the latter transition. The transition from abuse to dependence was associated with an early age of onset of regular alcohol use, being previously married, and student status. Remission was predicted by young age and a later age of onset of alcohol abuse. Conclusion The reduced number and magnitude of factors associated with transitions to dependence and remission suggest qualitatively different risk factors at these stages relative to other stages of progression. Further knowledge is needed concerning the mechanisms underlying these differences to guide selective and indicated prevention programs.

Hyperbaric oxygen therapy (HBOT) is the medical therapeutic use of oxygen at a higher atmospheric pressure. The United States Food and Drug Administration have approved several clinical applications for HBOT, but HBOT in traumatic brain injury (TBI) patients has still remained in controversial. The purpose of our study is to evaluate the benefit of HBOT on the prognosis of subacute TBI patients. We prospectively enrolled 44 patients with TBI from November 1, 2004 to October 31, 2005. The study group randomly included 22 patients who received HBOT after the patients' condition stabilization, and the other 22 corresponding condition patients were assigned into the matched control group who were not treated with HBOT. The clinical conditions of the patients were evaluated with the Glasgow Coma Scale (GCS) and Glasgow Outcome Scale (GOS) before and 3 to 6 months after HBOT. The GCS of the HBOT group was improved from 11.1 to 13.5 in average, and from 10.4 to 11.5 (p0.05) for control group. Among those patients with GOS = 4 before the HBOT, significant GOS improvement was observed in the HBOT group 6 months after HBOT. Based on this study, HBOT can provide some benefits for the subacute TBI patients with minimal adverse side effects.

Because of the rapid industrial and economic growth, Taiwan and other developing countries have faced an enormous increase in the number of motorcycles, which has subsequently caused a rapid increase of the motorcycle-related traumatic brain injuries (TBI). In order to tackle this serious problem, stepwise approaches for TBI were implemented in Taiwan from 1991 to 2007. Step 1 was to do a nationwide TBI registry in order to identify the risk factors and determinants. We found that the major cause of TBI in Taiwan was motorcycle-related injury, and very few motorcyclists wore a helmet. Step 2 was to launch the implementation of the helmet use law on June 1, 1997. A rapid decline of TBI hospitalizations and deaths was demonstrated soon thereafter. Step 3 was to enroll into international collaborations with the Global Spine and Head Injury Prevention Project (Global SHIP Project) groups for TBI. The comparative results thus obtained could be used to develop prevention strategies for developing countries. Step 4 was to implement clinical researches for TBI, which included a Propofol study, hyperbaric oxygen therapy (HBOT), brain parenchymal oxygen (PbtO2) monitoring, etc. Step 5 was to develop guidelines for the management of severe TBI in Taiwan. Through a 2-year period of review, discussion, and integration, a 9-chapter guideline was published in June 2007. In summary, our experience and process for management of TBI in Taiwan can be used as a reference for other developing countries.

Traumatic brain injury (TBI) is a major cause of death and disability. In the 2000 guidelines, one of the suggestions for TBI treatment was to maintain cerebral perfusion pressure (CPP)or = 70 mmHg. But in the 2003 guidelines, the suggestion was changed toor = 60 mmHg. There have been some discrepancies of opinions about this recommendation in recent publications. In this study, we retrospectively reviewed 305 severe TBI (STBI) patients with Glasgow Coma Scales (GCS)or = 8 between January 1, 2002 and March 31, 2003. The study group was stratified according to use or nonuse of intracranial pressure (ICP) monitoring, ICP levels, ages, and GCS levels in order to test the correlation between CCP and the prognosis. The patients50-year-old, with higher GCS level, with ICP monitoring, and with ICP levels20 mmHg had lower mortality rates and better prognosis (GOS) (p0.05 or 0.001). The patients in the GCS 3-5 subgroup had a significantly lower mortality and better prognosis if the CPP value was maintained higher than 70 mmHg (p0.05) The optimal CPP maintainedor = 60 mmHg did not fit in all STBI patients. Our study concludes that it is critical to maintain CPP substantially higher in lower GCS level patients.

There is an important need to develop a global expert disaster network for Mitigating against disasters such the Chi-Chi Earthquake, the Tsunami, Avian flu. This systems needs to target both man made and natural disasters. We propose the building of a Global Health Disaster Network, with advanced features such as educational capabilities, and expert knowledge reachback. We provide a strategic plan to building a global disaster Network and Mitigation system.

Coagulopathy in renal failure patients often makes them vulnerable to intracranial hemorrhage. Emergency decompression to remove the hematoma and to stop bleeding is always indicated. After the surgery, hemodialysis (HD) should be arranged to maintain the BUN/Cr. level, and I/O balance. During HD, intracranial pressure in all of the patients in this study fluctuated. This phenomenon always resulted in neurological deterioration in acute or chronic renal failure. We present intracranial pressure (ICP) changes during HD in five acute or chronic renal failure patients with intracranial hemorrhage. They all underwent craniectomy or craniotomy with ICP monitors implantation. Different HD protocols were arranged for these patients and then we observed clinical results. ICP elevated during HD and resulted in severe brain swelling. This situation was one of the clinical presentations of dialysis disequilibrium syndrome (DDS). Four patients died because of this complication and one survived. ICP fluctuation seemed to be correlated with the fluid amount and frequency of HD. The prevalence and pathophysiology of DDS remain unclear. Renal failure patient with intracranial hemorrhage may be complicated with DDS when HD was performed. An attempt to reduce the fluid amount and to increase the frequency of HD might help these patients.

CyberKnife stereotactic radiosurgery (CKSRS) has been proved effective in treating intra-cranial lesions. To treat acoustic neuroma (AN) patients with or without neurofibromatosis Type 2 (NF2) associations, the functional preservation of hearing, trigeminal nerve, and facial nerve are important. Twenty-one patients were treated with hypofractionated CKSRS. Fourteen non-NF2 and seven NF2 patients were enrolled. Cranial nerve function, audiograms, and magnetic resonance images (MRI) were monitored. Mean follow-up was 15 month. Tumors with volumes ranging from 0.13 to 24.8 cm3 (mean 5.4 cm3) were irradiated with the marginal dose 1800-2000 cGy/3 fractions. Tumors were treated with an 80 to 89% isodose line (mean 83%) and mean 97.9% tumor coverage. Two patients experienced hearing deterioration (16.7%) in the non-NF2 group, and 3 patients (50%) in the NF2 group. No facial or trigeminal dysfunction, brain stem toxicity, or cerebellar edema occurred. Tumor regression was seen in 9 patients (43%) and stable in 12 patients (57%). 100% tumor control rate was achieved. Hypofractionated CKSRS was not only effective in tumor control but also excellent in hearing preservation for non-NF2 AN. But for NF2 patients, although the tumor control was remarkable, hearing preservation was modest as in non-NF2 patients.

Syringomyelia is an uncommon disease that is caused most often by type I Chiari malformation, which develops in the hindbrain, and less frequently by other factors which are not limited to the hindbrain, including trauma, infection, or scoliosis. Idiopathic syringomyelia is rare. We present in this article a patient with idiopathic syringomyelia characterized by hypoesthesia and progressive weakness in the left lower limb. Decompression was attempted by means of laminectomy and a syringoarachnoid shunt. Motor, sensory, and bladder functions were monitored by the change in Japanese Orthopedic Association scores, which increased from 10 points preoperatively to 14 points 30 days postoperatively. This case demonstrates the effectiveness of surgical decompression in a patient with remarkable neurological deficit.

This population-based study was designed to determine the risk of patients with head injuries to develop surgically significant intracranial hematomas (SSIHs). A total of 28,500 cases of head injury were reviewed in Taipei City and Hualien County from 1988 to 1992. The Glasgow Coma Scale (GCS) was used to determine the severity of head injury. The presence of skull fracture and intracranial hematoma was determined by x-ray and computed tomographic (CT) scan, respectively. Those patients suffering from both loss of consciousness and skull fracture had a significantly greater risk of developing SSIHs than those having none or only one of these conditions. The relationship between skull fracture and severity of head injury revealed that the presence of a skull fracture in mildly head-injured patients could be used as an indicator to investigate the development of SSIHs before the occurrence of irreversible damage. The distribution of hematomas by location showed that a higher rate of SSIH resulting in parenchymal damage occurred when consciousness was lost. It also showed that epidural hematomas occurred more frequently with skull fractures. Skull fracture and impaired consciousness are important indices in determining the risk of developing SSIH.

Over the past few years, the use of endoscopy in neurosurgery has gradually gained importance. In this study we described the performance of Color Doppler Ultrasound (CDU)-guided endoscopic neurosurgery in ten patients with intracerebral hemorrhage. The completeness of hematoma evacuation was also evaluated.CDU, resectoscope, cutting loops, biopsy forcep, and the irrigation and suction device were the main instruments used in treating intracerebral hematoma. The CDU probe was utilized to locate the exact position of the hematoma and to provide direct visual control of the operation. The cutting loops and biopsy forcep were applied to morcellate and fragment the hematoma. Next, the fragmented hematoma was aspirated by a suction and irrigation device. CDU was then re-used to verify the completeness of hematoma resection and hemostasis as well as evaluate the position of midline shifting.The completeness of hematoma evacuation in our patient series was over 90% in three patients, over 50% in five patients, and less than 50% in two patients. One patient showed signs of rebleeding two days post-operatively and underwent conventional craniotomy.This endoscopic neurosurgical procedure caused less trauma around and along the route to the hematoma, and inflicted less damage to healthy brain tissue. Sonography, especially CDU, is quite helpful in the localization of hematoma and evaluation of intra- or post-operative bleeding. The operation time was also significantly shortened as compared to conventional craniotomy, thereby reducing the risk of operation.

This study was designed to examine neurobehavioral sequelae following closed head injuries. It adapted the Neurobehavioral Rating Scale (NRS) which was designed by Harvey S. Levin in 1987. The scale has been proven to be valid and reliable in previous Western studies and was translated by the authors into Mandarin with the consent of its designer. A total of 335 cases of closed head injury in eight major hospitals in Taipei were studied. The main findings obtained from this preliminary study were: 1) the correlation coefficients between raters ranged from 0.749 to 0.956, manifesting satisfactory reliability; 2) seven factors were obtained through factorial analysis of NRS, explaining 65.5% of the variance; and 3) significant differences in neurobehavioral change were found in patients with various degrees of severity and various types of head injuries. The results demonstrate that NRS is applicable to Chinese patients. Possible modification as well as elaboration of this scale is suggested.

We theoretically investigate the magnetic response of ensembles of semiconductor nano rings. Using our mapping method we simulated geometrical and material dispersion of the magnetic susceptibility of ensembles of the rings. Unlike the susceptibility of an individual ring the averaged susceptibility shows small temperature effect.

This study was designed to examine the descriptive epidemiology of head injuries in an urban population in the Taiwan area, Taipei City, during the period from July 1, 1987 to June 30, 1988. Clinical records reviewed included emergency room (ER) charts, inpatient charts of 19 major hospitals, death registration forms and medical examiners' reports in this city. A formulated definition was used to identify patients with head injuries. A total of 4,692 cases were collected, which included 4,319 hospital inpatients and 373 non-hospital deaths. The average incidence rate for head injury was 180/100,000 per year, 246/100,000 for males and 111/100,000 for females. The highest incidence rate was observed in the elderly group followed by the age group of 20-29 years. Sixty eight percent of the head injuries were caused by traffic accidents, 59.7 percent of which were involved in motorcycle rides. This rate was higher than those in any western reports. Among the 10-39 age group, the head injuries caused by traffic accidents were mainly due to motorcycle accidents. However, most of the children and the elderly who were injured were either pedestrians or bicycle riders. The average mortality rate was 23/100,000 per year, 34/100,000 for males and 12/100,000 for females. Initially the Glasgow Coma Scale was used in assessing the severity of head injuries. Seventy-two percent of the cases were considered mild, and 28 percent moderate to severe in degree, including 609 deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

An epidemiological study of head injuries in Hualien County, Taiwan, was undertaken from July 1, 1987 to June 30, 1988. Clinical records, including emergency room (ER) charts, inpatient charts from the four major hospitals and coroner or medical examiner reports in this county, were reviewed. A formulated definition was used in identifying patients with head injury. A total of 1,183 cases were identified. They included 975 hospital inpatients and 208 nonhospital deaths. The age-adjusted incidence rate for head injuries was 333/100,000 for all, 450/100,000 for males and 194/100,000 for females, with a male-to-female ratio of 2.32. The cumulative incidence rate from 0 to 69 years of age was 27.6% for males and 13.7% for females. The highest incidence rate was observed in the elderly group, whereas in other published reports the highest occurrence has been noted in the young adult group. An extraordinary 82% of the head injuries were associated with traffic accidents, 71% of which directly involved motorcycle riders. The age-adjusted mortality rate was 89/100,000 per year, 127/100,000 for males and 44/100,000 for females. The cumulative mortality rate was 8.7% for males and 3.2% for females. These are the highest rates ever reported. Sixty percent of the 1,183 patients had a moderate to severe injury or were dead. In the remaining 40%, the injury was considered mild. The elderly group presented with the highest percentage of moderate to severe degrees of injury, as well as mortality. Among traffic accident victims, those from motorcycle accidents and pedestrians had the highest percentage of severe head injuries.(ABSTRACT TRUNCATED AT 250 WORDS)

It is important to evaluate trauma patients with a properly graded severity system in the emergency management of these patients. In this study the Trauma and the Injury Severity Scores based on the evaluation of trauma patients at the emergency services of Mackay Memorial Hospital and Taipei Medical College Hospital, and the mortality rate of these patients is analyzed. There was not a single mortality in patients with a Trauma Score of 15 or 16 and no survival in the patients with Trauma Scores under 11. Eighty-three of 1000 patients (8.3%) had a Trauma Score under 16, and hospitalization was necessary for most of them. All the 22 fatal cases had an Injury Severity Score greater than 24. The mortality rate was 70.6% for the patients with an Injury Severity Score greater than 30. This was the first trial in Taiwan to evaluate patients with the Trauma Score in the hope of aiding medical and paramedical staffs in the selection hospitals to which to transfer patients. All patients having a Trauma Score under 14 should be transferred to well-equipped trauma centers and those with a better score to other hospitals. The Injury Severity Score is nowadays used widely in the world to evaluate the severity and to predict the outcome of the patients. By comparing and utilizing these two grading systems, a more accurate evaluation of the trauma patients can be expected.

This is a case of a 38-year-old male who developed painful ophthalmoplegia two years after head injury. Under the impression of Tolosa-Hunt syndrome, the patient received long term unsustained oral steroid therapy for two years. Persistent growth of the parasellar lesion was confirmed by computed tomography. Due to the aggravation of the symptoms, craniotomy and partial parasellar granulation tissue extirpation were performed. Symptoms were then gradually subsided. The pathological study confirmed the presence of granulation tissue with marked acute and chronic inflammatory cells. No evidence of malignancy was noted. No further steroid treatment was rendered to the patient and he was well in the following 18 months after the operation.

Aspergillus is a fungus of the class Ascomycetes which is of worldwide distribution. It is commonly found on decaying debris and in soil. Man comes into contact with a variety of Aspergillus species, however only seven species have been implicated in human infections. Aspergillus fumigatus has accounted for approximately 90% of Aspergillus infections [9], and the common Aspergillus flavus accounts for the rest. Aspergillosis of the paranasal sinus is rare, except in the Sudan, where various publications have indicated the disease to be endemic [7,10]. The maxillary sinus is most frequently involved. Peterson et al., in a review of world literature in 1982, reported fewer than 120 cases of aspergillosis of the maxillary sinus [9]. Infection of the sphenoid sinus is extremely rare. Comoretto et al. in 1986 reported only 14 cases, in a review of world literature [1].

Magnetic interactions between permalloy elliptical rings in different arrangements of two-dimensional arrays were investigated. The edge-to-edge distances between units along the long axis were changed from 2μm down to 100nm. Formation of domain walls during magnetization reversals results in magnetostatic coupling between adjacent units. When two neighboring rows were shifted one-half pitch along the short axis to form a shift-type array, large stable field range for vortex states was obtained.

We report a simulation on the magneto-biexciton system of asymmetrical InAs/GaAs nano-rings, using a smooth three dimensional confinement potential which realistically describes electronic properties of the rings. In our calculation, we use the Hartree approximation to calculate the self-consistent energy for exciton and biexciton confined in the system. We simulate recombination energy, binding energy and their diamagnetic shifts and compare those results with experimental data obtained from the magneto-photoluminescence measurement. We found that using the realistic geometry and composition of the asymmetric nano-ring in our simulations we are able to reproduce experimental data with good accuracy.

In the present study, we conducted pre-ganglionic decentralization (or sympathetic trunk resection) of the superior cervical ganglia and observed alterations in several physiological functions and in the monoamine content of different brain regions. Over an ambient temperature range of 8-30 degrees C, these sympathectomized rats maintained their rectal temperatures within a normal limit displayed by the intact controls. These sympathectomized animals, although showing no change in the level of spontaneous pain threshold or motor activity, did display an increased sensitivity of analgesic responses to morphine administration or locomotor stimulant responses to amphetamine administration. Biochemical examination revealed that these sympathectomized animals had a higher level of norepinephrine, dopamine or 5-hydroxytryptamine in the hypothalamus, as well as a higher level of dopamine in the corpus striatum. However, in the brainstem, these sympathectomized animals had a unaltered monoamine level. The data indicate that, in a sympathectomized condition, changes in the monoamine content of different brain regions may be correlated with the above-mentioned alterations in somatosensory and motor neural functions.

The influence of cold stress, heat stress, or various agents on the development of brain edema were assessed in rats following a cryogenic brain lesion. Brain edema was induced by local cold injury to the cortex. Cerebral edema was assessed 0.5, 3.0 or 24 h after a cryogenic brain lesion by measuring the water content of two hemispheres. Pretreatment of animals with sodium pentobarbital (15 or 30 mg/kg, i.p.) or lidocaine (15 mg/kg, i.p.) did not influence the development of brain edema. In addition, pretreatment with an external heat stress (heat exposure of 32 degrees C for 6 h) exaggerated significantly the development of brain edema in the rat following a cryogenic brain lesion. On the other hand, pretreatment of animals with either external cold stress (cold exposure of 8 degrees C for 6 h), glycerol (10% 10 ml, i.p.), mannitol (15% 10 ml, i.p.), gamma-hydroxybutyric acid (300 mg/kg, i.p.), metiamide (5 mg/kg, i.p.), dexamethasone (4 mg/kg, i.p.), aminophylline (100 mg/kg, i.p.), or ketamine (30 mg/kg, i.p.) inhibited significantly the brain edema formation.

Residues of chlorinated hydrocarbon insectidies and some of their metabolites, including p,p'-DDT, p,p'-DDD, p,p'-DDE, gamma-BHC, aldrin, dieldrin, heptachlor and heptachlor epoxide, were examined in the soils collected from 21 tea-gardens distributed in 15 countries of 6 prefectures in 1977, and from 100 locations distributed in 46 counties of 10 prefectures in 1984 in Taiwan. Although the use of these chlorinated hydrocarbon insecticides has been banned for many years, minor amounts of residues in the soils have still been detected. From 1977 to 1984, average residues of the chlorinated hydrocarbon insecticides and their metabolites in the soils of tea-gardens decreased from 5.64 to 0.06 ppb for gamma-BHC, 97 54 to 1.10 ppb for aldrin, 35.91 to 1.00 ppb for p,p'-DDE, 17.41 to 0.28 ppb for dieldrin, and 30.17 to 3.42 ppb for p,p'-DDT. But the number of positive cases increased for all chlorinated hydrocarbon insecticides tested, the residual levels were not significantly different among soils with different physiochemical properties or among soil layers. No significant amount of these insecticides was found in the processed tea.