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Selected AbstractsCorporate Governance and Capital Structure Decisions of the Chinese Listed FirmsCORPORATE GOVERNANCE, Issue 2 2002Yu Wen This paper studies the relationship between some characteristics of the corporate board and the firm's capital structure in Chinese listed firms. The findings provide some preliminary empirical evidence and seem to suggest that managers tend to pursue lower financial leverage when they face stronger corporate governance from the board. However, the empirical results of the relationships are statistically significant only in the case of the board composition and the CEO tenure. The results are statistically insignificant in the case of the board size and fixed CEO compensation. This may in general suggest that, up to the time period of our investigation, the corporate board structures and processes in Chinese listed firms might not as yet be fully working in the manner, or as well, as might have been so far assumed on the basis of Western theoretical finance literature. [source] In vitro viability, mitogenicity and clonogenic capacity of periodontal ligament cells after storage in four media at room temperatureDENTAL TRAUMATOLOGY, Issue 2 2000M. Ashkenazi Abstract , The choice of storage medium for preserving traumatically avulsed teeth is important for the success of future replantation. The objective of this study was to compare the effectiveness of four recommended storage media (Hank's balanced salt solution [HBSS], culture medium, , minimal essential medium [,-MEM], and ViaSpan) to preserve cultured periodontal ligament fibroblasts (PDLF) at room temperature (22°C). PDLF were obtained from explants of extracted healthy human teeth. Plates with confluent PDLF were soaked in the various media for 2, 8 and 24 h at room temperature. A control group was incubated with culture medium at 37°C. After incubation, viability of the cells was determined by trypan blue exclusion test. Viable cells were then analyzed for mitogenic (with thymidine) and clonogenic capacity (by culturing one cell/well). Viability of PDLF stored up to 24 h was comparable in all tested media, and the differences were limited to 1%,3%. PDLF stored for up to 24 h in various media had statistically comparable mitogenicity to the control group. After 8 h of storage, the differences were limited to 2%,9%, except for the ,-MEM group which had 23%,29% lower mitogenic capacity compared to the control group. Increasing the storage time up to 24 h further decreased the mitogenicity of the cells by 22%,47%. The highest mitogenicity after 24 h of storage was found in PDLF stored in culture medium or HBSS, and the lowest in ,-MEM. PDLF stored for 2,8 h in various media had a comparable clonogenic capacity to the control group. However, after 24 h, the cells' clonogenic ability dropped by 14%,66%. A similar trend of reduction was noted in the mitogenic and clonogenic capacity, although it was statistically significant only in the clonogenic capacity. Culture medium and ViaSpan, followed by HBSS, were the most effective in preserving the clonogenic capacity of PDLF after 24 h of storage. The lowest clonogenic capacity after 24 h of storage was in the ,-MEM group (66%, P<0.0025). In conclusion, culture medium, followed by HBSS and ViaSpan, was the most effective media for preserving the viability, mitogenicity and clonogenic capacity of PDLF stored for up to 24 h at room temperature. The lowest functional abilities were found in PDLF stored in ,-MEM. [source] Severity of personality disorders and suicide attemptACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2009H. Blasco-Fontecilla Objective:, Severity of personality disorders (PDs) may be more useful in estimating suicide risk than the diagnosis of specific PDs. We hypothesized that suicide attempters with severe PD would present more attempts and attempts of greater severity/lethality. Method:, Four hundred and forty-six suicide attempters were assessed. PD diagnosis was made using the International Personality Disorder Questionnaire , Screening Questionnaire. PDs were classified using Tyrer and Johnson's classification of severity (no PD, simple PD, diffuse PD). Severity/lethality of attempts was measured with the Suicide Intent Scale, Risk-Rescue Rating Scale and Lethality Rating Scale. Results:, Attempters with severe (diffuse) PD had more attempts than the other groups. After controlling for age and gender, this difference remained significant only for the younger age group and women. There was no relationship between severity of PDs and severity/lethality of attempts. Conclusion:, Younger female attempters with severe PD are prone to repeated attempts. However, the severity of PD was not related to the severity/lethality of suicide attempts. [source] Serotonin and dopamine transporter binding in children with autism determined by SPECTDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 8 2008Ismo Makkonen MD Disturbances in the serotonergic system have been recognized in autism. To investigate the association between serotonin and dopamine transporters and autism, we studied 15 children (14 males, one female; mean age 8y 8mo [SD 3y 10mo]) with autism and 10 non-autistic comparison children (five males, five females; mean age 9y 10mo [SD 2y 8mo]) using single-photon emission computed tomography (SPECT) with [123I] nor-,-CIT. The children, with autism were studied during light sedation. They showed reduced serotonin transporter (SERT) binding capacity in the medial frontal cortex, midbrain, and temporal lobe areas. However, after correction due to the estimated effect of sedation, the difference remained significant only in the medial frontal cortex area (p=0.002). In the individuals with autism dopamine transporter (DAT) binding did not differ from that of the comparison group. The results indicate that SERT binding capacity is disturbed in autism. The reduction is more evident in adolescence than in earlier childhood. The low SERT binding reported here and the low serotonin synthesis capacity shown elsewhere may indicate maturation of a lesser number of serotonergic nerve terminals in individuals with autism. [source] Follicular variant of papillary carcinoma: Cytologic findings on FNAB samples,experience with 16 casesDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2001Franco Fulciniti M.D. Abstract Between January 1, 1992 and December 31, 1997, a cytopathological diagnosis of follicular variant of papillary thyroid carcinoma (FVPC) was made on a series of 16 out of 18 patients with palpable nodules who underwent fine-needle aspiration biopsy (FNAB) in our Department. The results of aspiration biopsy were followed by histopathological examination of the surgically excised tissues. There were three false-negative aspirations (16.6%), of which two were probably bound to fine-needle sampling and one due to a mixture of benign and malignant cells which had originally gone unrecognized. The accuracy of the cytopathologic diagnosis in this variant was 88.8%. An analysis of the diagnostic cytopathological criteria was performed, which demonstrated the importance of both architectural features (monolayered and branching sheets, microacinar structures, and their combinations) and nuclear features (presence of nuclear grooves). Background -bound features were mainly represented by dense, nonfilamentous colloid. The cytopathologic findings in FVPC were compared to those found in a series of 10 usual papillary carcinomas (UPC) and 10 follicular neoplasms (FN). These latter had originally been diagnosed by FNAB and were subsequently classified histologically as follicular adenoma (n = 6), follicular carcinoma (n = 3), or adenomatoid colloid nodule (n = 1). Statistical evaluation was performed on the cytopathological findings in the three classes of lesions (FVPC, UPC, and FN) as to their presence and relative frequency or absence by using a nonparametric one-way ANOVA (Kruskall-Wallis) and, where necessary, a Mann-Whitney U test. Papillary cellular fragments and multinucleated giant cells (P < 0.005), nonfilamentous dense colloid, squamoid cells, and syncytia were significantly more represented in UPC than in FVPC (P < 0.05), while histiocytes were significantly more frequent in FVPC (P < 0.005). Other nuclear and/or background features were significant only in the distinction between papillary carcinomas as a group and FN. The cytological differential diagnosis of the FVPC is briefly discussed with relevance to the possible pitfalls caused by its peculiar cyto- and histomorphology. Diagn. Cytopathol. 2001;25:86,93. © 2001 Wiley-Liss, Inc. [source] Torsional response of symmetric buildings to incoherent and phase-delayed earthquake ground motionEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 7 2003Ernesto Heredia-Zavoni Abstract This paper studies the effect of coherency loss and wave passage on the seismic torsional response of three-dimensional, multi-storey, multi-span, symmetric, linear elastic buildings. A model calibrated against statistical analyses of ground motion records in Mexico City is used for the coherency function. The structural response is assessed in terms of shear forces in structural elements. Incoherence and wave passage effects are found to be significant only for columns in the ground level of stiff systems. The increase of column shears in the ground level is much higher for soft than for firm soil conditions. For the torsionally stiff systems considered, it is found that incoherent and phase-delayed ground motions do not induce a significant rotational response of the structure. The use of a code eccentricity to account for torsion due to ground motion spatial variation is assessed. On firm soil, the use of a base shear along with an accidental eccentricity results in highly overestimated shear forces; however, for soft soil conditions, code formulations may result in underestimated shear forces. Copyright © 2003 John Wiley & Sons, Ltd. [source] Effects of landscape composition and substrate availability on saproxylic beetles in boreal forests: a study using experimental logs for monitoring assemblagesECOGRAPHY, Issue 2 2006Heloise Gibb Intensive forestry practises in the Swedish landscape have led to the loss and fragmentation of stable old-growth habitats. We investigated relationships between landscape composition at multiple scales and the composition of saproxylic beetle assemblages in nine clear-cut, mature managed and old-growth spruce-dominated forest stands in the central boreal zone of Sweden. We set out fresh spruce and birch logs and created spruce snags in 2001,2002 to experimentally test the effects of coarse woody debris (CWD) type and forest management on the composition of early and late successional, and red-listed saproxylic beetle assemblages. We examined effects of CWD availability at 100 m, and landscape composition at 1 and 10 km on saproxylic beetle abundances. Additionally, we tested whether assemblage similarity decreased with increasing distance between sites. We collected beetles from the experimental logs using eclector and window traps in four periods during 2003. CWD was measured and landscape composition data was obtained from maps of remotely sensed data. The composition of saproxylic beetles differed among different CWD substrates and between clear-cuts and the older stand types, however differences between mature managed and old-growth forests were significant only for red-listed species. Assemblage similarities for red-listed species on clear-cuts were more different at greater distances apart, indicating that they have more localised distributions. CWD availability within 100 m of the study sites was rarely important in determining the abundance of species, suggesting that early successional saproxylic beetles can disperse further than this distance. At a larger scale, a large area of suitable stand types within both 1 and 10 km resulted in greater abundances in the study sites for several common and habitat-specific species. The availability of suitable habitat at scales of 1,10 km is thus likely to be important in the survival of many saproxylic species in forestry-fragmented areas. [source] Fitness and body size in mature odonatesECOLOGICAL ENTOMOLOGY, Issue 2 2000Natalia Sokolovska Summary The relationship between body size and fitness components in odonates was examined using a meta-analysis of 33 published studies. There was a positive and significant overall effect of body size on mating rate and lifetime mating success among males. There was also a weaker but still significant positive effect of body size on survivorship of males. The relationship between body size, mating rate, longevity, and lifetime mating success differed significantly between males of territorial and nonterritorial species. The effect of body size was significant for all fitness components in territorial species but significant only for longevity and lifetime mating success in nonterritorial species. Effect sizes appeared to be strongest on longevity in both sexes, and on male mating rate in territorial species. Other effect sizes, even when significant, were small. Despite a much smaller data set, female fitness also increased significantly with body size. Both clutch size and longevity showed a significant positive relationship with body size. These results suggest that there is a general fitness benefit to large size in odonates. Nevertheless, significant heterogeneity is apparent in this effect, which can be attributed to sex, mating system, and fitness component. Finally, these analyses point to inadequacies in the current data that need further study before the potentially rich patterns in size effects on fitness can be explored more thoroughly. [source] Positive health-care effects of an alcohol ignition interlock programme among driving while impaired (DWI) offendersADDICTION, Issue 11 2007Bo Bjerre ABSTRACT Aims To compare the costs of hospital care and sick leave/disability pensions between two groups of driving while impaired (DWI) offenders: participants in an alcohol ignition interlock programme (AIIP) and controls with revoked licences, but with no comparable opportunity to participate in an AIIP. Setting As an alternative to licence revocation DWI offenders can participate in a voluntary 2-year AIIP permitting the offender to drive under strict regulations entailing regular medical check-ups. The participants are forced to alter their alcohol habits and those who cannot demonstrate sobriety are dismissed from the programme. Participants are liable for all costs themselves. Design Quasi-experimental, with a non-equivalent control group used for comparison; intent-to-treat design. Based on the number of occasions/days in hospital and on sick leave/disability pension, the health-care costs for public insurance have been calculated. Finding Average total health-care costs were 25% lower among AIIP participants (1156 individuals) than among controls (815 individuals) during the 2-year treatment period. This corresponds to over ,1000 (SEK9610) less annual costs per average participant. For those who complete the 2-year programme the cost reduction was more pronounced; 37% during the treatment and 20% during the post-treatment period. Conclusions The positive health-care effects were due apparently to reduced alcohol consumption. The social benefit of being allowed to drive while in the AIIP may also have contributed. The reduction in health-care costs was significant only during the 2-year treatment period, but among those who completed the entire AIIP sustained effects were also observed in the post-treatment period. The effects were comparable to those of regular alcoholism treatment programmes. [source] Toxicokinetics of waterborne bisphenol a in landlocked salmon (Salmo salar m. Sebago) eggs at various temperaturesENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2001Jani O. Honkanen Abstract Eye-pigmented eggs of landlocked salmon were exposed to waterbone [14C]-labeled bisphenol A at four temperatures (2, 6, 8, and 12°C). Both in accumulation and depuration experiments, the eggs were exposed to a bisphenol A concentration of 1 ,g/L for 196 h. In the depuration experiment, the exposed eggs were placed into clean water for 96 h. At each sampling time, the eggs were dissected into three parts (eggshell, embryo, and yolk sac), and all of these parts were weighed and analyzed separately in a liquid scintillation counter. The results show that waterborne bisphenol A accumulates in developing salmon eggs. Accumulation of bisphenol A showed a clear trend both in whole eggs and in dissected parts: the higher the temperature, the higher the uptake rate constant and the concentration of bisphenol A. Steady state was reached only in the embryos at the lowest temperature; in other cases, accumulation was linear. Depuration was significant only in the embryos at 2 and 6°C. As the accumulation and the depuration results show, the elimination of bisphenol A was evidently more significant at lower temperatures. [source] Intraepidermal nerve fibre density, quantitative sensory testing and nerve conduction studies in a patient material with symptoms and signs of sensory polyneuropathyEUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2006S. Løseth Small diameter nerve fibre (SDNF) neuropathy is an axonal sensory neuropathy affecting unmyelinated (C) and thin myelinated (A-delta) fibres. We have evaluated 75 patients with symptoms and signs suggesting SDNF dysfunction with or without symptoms and signs of co-existing large diameter nerve fibre involvement. The patients were examined clinically and underwent skin biopsy, quantitative sensory testing (QST) and nerve conduction studies (NCS). The purpose of this study was to compare the relationship between the different methods and in particular measurements of thermal thresholds and intraepidermal nerve fibre (IENF) density in the same site of the distal leg. The main subdivision of the patient material was made according to the overall NCS pattern. Patients with normal NCS (38) had 6.4 ± 3.8 and patients with abnormal NCS (37) had 4.4 ± 3.4 IENF per mm (P = 0.02). Limen (difference between warm and cold perception thresholds) was significantly higher (more abnormal) in those with abnormal than in those with normal NCS (22.1 ± 9.1 vs. 13.4 ± 5.6, P < 0.0001). Cold perception threshold was more abnormal (P < 0.0001) than warm perception threshold (P = 0.002). Correlation between IENF and QST was statistically significant only when NCS was abnormal, and thus dependent of a more severe neuropathic process in SDNFs. [source] Dispersive Effects in Chemomechanical Reactions with Polyallylamine-Derived HydrogelsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 8 2008Kazuaki Kato Abstract Volume changes of polyallylamine-derived hydrogels crosslinked with glutaraldehyde are determined with a large variety of effector compounds. Monocarboxylic effectors lead to smaller contractions, in contrast to dicarboxylate structures, which allow more effective non-covalent crosslinking between the positively charged nitrogen centers of the polymer backbone. Electroneutral compounds lead to negligible changes, whereas effectors with either a large p -moiety like in naphthoic acid or phenyl derivatives with polarizable substituents induce large contractions. This finding is in line with significant contributions of van der Waals interactions between the effectors within the hydrogel. Chemomechanical differences between regioisomeric effectors such as p - and o -nitrobenzoic acid are in agreement with independent results of dispersive interactions in related complexes. The volume decrease corresponds almost entirely to the gravimetrically determined water content of the gels. The acidity profile shows a strong contraction above pH 10, which is consistent with the known pK value of such polyamines. NMR spectra of the gels indicate strong binding of the effectors by line broadening, which is significant only for the chemomechanically active compounds. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Relationships among vertically structured in situ measures of turbulence, larval fish abundance and feeding success and copepods on Western Bank, Scotian ShelfFISHERIES OCEANOGRAPHY, Issue 3 2002ChristianS. Using vertically stratified data of the abundance of silver hake (Merluccius bilinearis) larvae and concentrations of copepods collected in the field, we examine relationships among the vertical distribution of larval fish, their potential prey, feeding success and water column turbulence. Water column turbulence and associated stratification parameters were estimated from: (i) in situ measures of turbulent kinetic energy dissipation (,) provided by an EPSONDE profiler; (ii) in situ wind speed; (iii) the Richardson number (Ri); and (iv) the buoyancy frequency (N2). Small (< 5 mm total length) silver hake were more abundant in the least turbulent waters (i.e. at a minimum in the rate of dissipation of turbulent kinetic energy, , < 10,7 W kg,1; Ri > 0.25; N2 > 0.001 (rad s,1)2). Partial correlations amongst ,, N2 and small hake larvae were significant only for N2. The abundance of larger (> 5 mm total length) hake larvae was positively correlated with depth and was not associated with either , or N2. Vertical distributions of three potential prey (classified by stage) were variable. Early stage copepodids were positively correlated with N2 and negatively correlated with ,. We found no evidence of diel distribution patterns for small (< 5 mm total length) hake larvae or for any of the developmental stages of the copepods examined. Neither estimate of water column turbulence inferred from wind speed nor from Ri was meaningfully related to in situ estimates of , or to larval fish abundance. Feeding success, measured either as prey items (gut),1, average prey length, or total prey volume (gut),1, was not related to predicted encounter rates between days. However, the average prey length (gut),1 was significantly (P < 0.01) related to water column turbulence. These conflicting results suggest that the relationship between larval feeding and the environment is more complicated than assumed. We conclude that without substantial high resolution in situ examination of the relationship between the vertical distributions of turbulence, larvae and their prey, the growing acceptance in the secondary literature that turbulence has a positive and biologically meaningful effect on trophic interactions between fish and their zooplankton prey (a generalization based largely on modelling and laboratory experiments) is premature. [source] Scaling of body temperature in mammals and birdsFUNCTIONAL ECOLOGY, Issue 1 2008Andrew Clarke Summary 1We examine variation associated with phylogeny in the scaling of body temperature in endotherms, using data from 596 species of mammal and 490 species of bird. 2Among higher groups of mammals there is statistically significant scaling of body temperature with mass in Marsupialia (positive), Ferae and Ungulata (both negative). In mammalian orders where data are available for at least 10 species, scaling is negative in three orders (Carnivora, Erinaceomorpha and Artiodactyla), positive in one (Chiroptera) and not significant in seven others. There is no relationship apparent between the scaling of body temperature and the existence of gut fermentation. As expected, monotremes exhibit the lowest body temperatures, but within marsupials diprotodonts have a mean body temperature higher than several placental groups; the traditional ranking of body temperatures in the sequence monotremes , marsupials , placentals is thus misleading. 3In birds, scaling relationships are significant only for Ciconiiformes (strongly negative) and Passeriformes (weakly positive). 4When allowance is made for phylogenetic effects, there is no significant relationship between temperature in body mass in mammals overall, but an inverse and almost significant relationship in birds. 5This study indicates a complex relationship between body mass, body temperature and metabolic rate in mammals and birds, mediated through ecology. [source] Adopting the operating microscope in thyroid surgery: Safety, efficiency, and ergonomics,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2010Bruce J. Davidson MD Abstract Background. Our aim was to assess the safety and efficiency of operating microscope use by surgeons in thyroid surgery to reduce static neck flexion. Methods. A retrospective case review comparing thyroidectomies performed using an operating microscope to those using surgical loupes was done. Operative times and incidence of complications were compared between total thyroidectomy procedures done with either microscope or loupes. Results. The use of microscope in 51 thyroidectomies (including 20 for malignancy with central compartment node dissection [CND] and 9 for substernal goiter [SG]) was compared with 65 cases (15 with CND and 11 with SG) done previously using loupes. Surgical times using the microscope were longer (p = .0001), but the increase was significant only in the subset of patients who underwent thyroidectomy with CND. There was no difference in complications between the groups. Conclusion. The use of an operating microscope during thyroidectomy is safe with modest increases in surgical time. © 2009 Wiley Periodicals, Inc. Head Neck, 2010 [source] Almotriptan Reduces the Incidence of Migraine-Associated Symptoms: A Pooled AnalysisHEADACHE, Issue 2002Roger Cady MD Objectives.,Evaluate the reduction in migraine-associated symptoms after administration of a single oral dose of almotriptan. Methods.,This pooled analysis (N=1773) used data from three randomized, placebo-controlled, phase III trials (studies A, B, and C) to determine the incidence of migraine-associated symptoms (defined as nausea, vomiting, photophobia, and phonophobia) 2 hours after a single oral dose of study medication (almotriptan, sumatriptan, or placebo). Outcome data was extracted from studies A and B for placebo and the almotriptan 6.25-mg and 12.5-mg groups, and from study C for placebo, almotriptan 12.5-mg, and sumatriptan 100-mg groups. Results.,The incidence of nausea, photophobia, and phonophobia at 2 hours after dosing with study medication was significantly reduced (all P < .05) with almotriptan 6.25 mg or 12.5 mg compared with placebo. The percentage of patients with vomiting was lower with both doses of almotriptan in studies A and B compared with placebo, although differences were significant only for the 6.25-mg dose in study A (P < .001). For study C, the incidence of nausea, vomiting, photophobia, and phonophobia was similar for almotriptan and sumatriptan and lower than with placebo at 2 hours after dosing. Significant reductions (all P < .05) versus placebo were observed in the incidence of vomiting and phonophobia with almotriptan 12.5 mg, and photophobia and phonophobia with sumatriptan 100 mg. Conclusion.,Almotriptan provides relief from migraine-associated symptoms of nausea, vomiting, photophobia, and phonophobia, and thus represents an attractive treatment option for a wide spectrum of migraine symptomatology. [source] Ten Dimensions of Health and Their Relationships with Overall Self-Reported Health and Survival in a Predominately Religiously Active Elderly Population: The Cache County Memory StudyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2006Truls Østbye MD OBJECTIVES: To document the extent of healthy aging along 10 different dimensions in a population known for its longevity. DESIGN: A cohort study with baseline measures of overall self-reported health and health along 10 specific dimensions; analyses investigated the 10 dimensions as predictors of self-reported health and 10-year mortality. SETTING: Cache County, Utah, which is among the areas with the highest conditional life expectancy at age 65 in the United States. PARTICIPANTS: Inhabitants of Cache County aged 65 and older (January 1, 1995). MEASUREMENTS: Self-reported overall health and 10 specific dimensions of healthy aging: independent living, vision, hearing, activities of daily living, instrumental activities of daily living, absence of physical illness, cognition, healthy mood, social support and participation, and religious participation and spirituality. RESULTS: This elderly population was healthy overall. With few exceptions, 80% to 90% of persons aged 65 to 75 were healthy according to each measure used. Prevalence of excellent and good self-reported health decreased with age, to approximately 60% in those aged 85 and older. Even in the oldest old, the majority of respondents were independent in activities of daily living. Although vision, hearing, and mood were significant predictors of overall self-reported health in the final models, age, sex, and cognition were significant only in the final survival models. CONCLUSION: This population has a high prevalence of most factors representing healthy aging. The predictors of overall self-reported health are distinct from the predictors of survival in this age group and, being potentially modifiable, are amenable to clinical and public health efforts. [source] The non-linear dynamics of output and unemployment in the U.S.JOURNAL OF APPLIED ECONOMETRICS, Issue 4 2001Filippo Altissimo This paper studies the joint dynamics of U.S. output and unemployment rate in a non-linear VAR model. The non-linearity is introduced through a feedback variable that endogenously augments the output lags of the VAR in recessionary phases. Sufficient conditions for the ergodicity of the model, potentially applying to a larger class of threshold models, are provided. The linear specification is rejected in favour of our threshold VAR. However, in the estimation the feedback is found to be statistically significant only on unemployment, while it transmits to output through its cross-correlation. This feedback effect from recessions generates important asymmetries in the propagation of shocks, a possible key to interpret the divergence in the measures of persistence in the literature. The regime-dependent persistence also explains the finding that the feedback from recession exerts a positive effect on the long-run growth rate of the economy, an empirical validation of the Schumpeterian macroeconomic theories. Copyright © 2001 John Wiley & Sons, Ltd. [source] Human settlement and baobab distribution in south-western MaliJOURNAL OF BIOGEOGRAPHY, Issue 11 2007Chris S. Duvall Abstract Aim, Human settlement establishment and reproduction of the baobab tree (Adansonia digitata) appear spatially and temporally dependent because baobabs are abundant in many settlement sites in Africa. This paper tests the spatiotemporal relationship between baobab and settlement distribution. Location, South-western Mali. Methods, In an area of 183 km2, 1240 baobabs were located and mapped, their diameters measured, and habitat characteristics recorded for each individual. All occupied (n = 9) and abandoned (n = 84) settlements were located and mapped, and occupation dates were determined through interviews. Chi-squared analysis indicated baobab habitat preferences, and bivariate point-pattern analysis tested baobab,settlement spatiotemporal independence. Results, Baobabs and human settlements are positively spatially associated at most distances and for all baobab size-class,settlement age-class pairs. However, positive spatial association is significant only at distances < 500 m, and young settlements and large baobabs are not significantly associated. Positive association between small and large baobabs is marginally significant at <300 m, but observed significance is less than that for baobab,settlement positive association. Baobab abundance is not evenly distributed across the range of habitats it occupies; recruitment is strongest in settlements and fields, and on cliffs, while mortality is highest on cliffs. Ethnographic observations suggest that human settlement practices and fruit use are the main human factors contributing to baobab,settlement positive spatial association. Main conclusions, There are three main conclusions: (1) Human settlement and baobab recruitment are spatially dependant because settlement leads directly and indirectly to the development of baobab groves at settlement sites. (2) The lower than expected abundance of mature individuals in natural habitats, and the habitat preferences of the observed population, suggest that baobabs were introduced to south-western Mali, probably centuries ago. (3) Human mobility over decadal time-scales is necessary to maintain baobab population structure in landscapes dominated by shifting land use, where baobabs are not purposefully planted. Baobab population processes in such landscapes occur at the scale of human settlement. [source] Open flap debridement with or without intentional cementum removal: a 4-month follow-upJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2005Antonio Wilson Sallum Abstract Objectives: The aim of this study was to investigate the influence of cementum removal on periodontal repair. Material and Methods: Forty subjects with chronic periodontitis and presenting, at least, two proximal sites in anterior teeth (upper or lower) with probing depth 5 mm were selected. After oral hygiene instructions and ultrasonic supragingival instrumentation, the subjects were randomly assigned for one of the following groups: CIC, scaled with Gracey curettes; CIUS, scaled with ultrasonic device; CDC, calculus deattachment with Gracey curettes and brushing with saline solution; and CDUS, calculus deattachment with ultrasonic device and brushing with saline solution. Full-thickness flaps were reflected and the instrumentation was performed with a clinical microscope. Probing depth (PD), relative gingival margin level (RGML) and relative attachment level (RAL) were registered at five experimental periods: baseline and 30, 60, 90 and 120 days postoperative. Results: All the approaches were able to markedly reduce the PD values from the baseline to the other evaluation periods (p<0.0001). The increase in RGML values was statistically significant only for the CDUS group. There were no statistically significant differences between the baseline and postoperative values in all groups for the RAL changes. The changes in RAL were statistically significant only among the groups CDC and CDUS (p<0.0001). Conclusion: The conventional scaling and root planing and the calculus deattachment were effective in reducing the probing depth values, regardless of the instrumentation method. [source] Localized Chronic Fibrosing Vasculitis or Localized Erythema Elevatum Diutinum?JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005L. Clarke Localized chronic fibrosing vasculitis is a rare dermatosis that histologically resembles late-stage erythema elevatum diutinum (EED) but has a different clinical presentation. A 62-year-old male presented with bilateral nodules on his heels that first appeared two years ago and over the past six months had become extremely painful. He denied any recent trauma to the sites, and his medical history was significant only for diabetes mellitus, coronary artery disease, and osteoarthritis. Physical exam demonstrated focally ulcerated violet-red three-centimeter nodules on the medial aspects of both heels. Biopsy revealed dense concentric and lamellar fibrosis with foci of leukocytoclastic debris and a sparse infiltrate of histiocytes, neutrophils, eosinophils, and lymphocytes. No granulomas were present, and histochemical stains and tissue cultures for microorganisms were negative. Imaging studies showed no evidence of underlying osteomyelitis, cellulitis, or abscess formation. Laboratory studies demonstrated a markedly elevated IgA level that was shown to be polyclonal on serum immunofixation studies. All peripheral blood cell counts were normal. Thorough evaluations for systemic vasculitides and connective tissue disorders were negative. A diagnosis of localized chronic fibrosing vasculitis was made. This case illustrates the clinicopathologic overlap between this disorder and EED. [source] Dietary intakes and nutrient status of vegetarian preschool children from a British national surveyJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 3 2000C.W. Thane Background Dietary intakes and nutrient status were compared in meat-eaters and non-meat-eaters from the National Diet and Nutrition Survey of children aged 1.5,4.5 years. Methods Children (n = 1351) were categorized as ,omnivores' or ,vegetarians', according to whether they consumed meat or meat products during a 4-day dietary record. Blood samples were also obtained for analysis of haematological and biochemical nutrient status. Results Three per cent of children were ,vegetarian'. They consumed higher proportions of milk and milk products, although this was significant only in older children (P = 0.007), owing to high consumption by the high proportion of Asian children. In vegetarians, energy intakes tended to be lower in both age groups. Percentage energy from protein and fat were lower, while that from carbohydrate was higher compared with omnivores. Cholesterol intakes were lower, significantly so for younger children (P < 0.001). Intakes of micronutrients were either higher (vitamins C and E, potassium) or lower (niacin and sodium) in younger vegetarians compared with omnivores. Energy-adjusted intakes of iron and zinc did not differ significantly from those of omnivores, although both intakes were low in many children (6,20% < LRNI), particularly in the younger group. Haematological and biochemical nutrient status indices showed few differences. Serum ferritin was lower in vegetarians, significantly so in younger children (P = 0.002). Antioxidant vitamin (A, C and E) status tended to be higher in vegetarians, while vitamin B12 intakes and status were more than adequate. Apart from poorer vitamin D intake and status in older Asian vegetarians, very few ethnic differences were observed. Conclusions Nutrient intakes and status were generally adequate in preschool children who did not eat meat. Although serum ferritin levels were inferior (particularly in vegetarians under 3 years old), the lower intakes of fat, cholesterol and sodium, and higher antioxidant vitamin intakes and status indices were potentially beneficial. Given a balanced diet, adequate nutrient intakes and status can be maintained without consuming meat. [source] Original Article: A prospective study of uric acid by glucose tolerance status and survival: the Rancho Bernardo StudyJOURNAL OF INTERNAL MEDICINE, Issue 6 2010C. K. Kramer Abstract., Kramer CK, von Mühlen D, Jassal SK, Barrett-Connor E (University of California, La Jolla, CA; and Hospital de Clinicas de Porto Alegre, RS, Brazil). A prospective study of uric acid by glucose tolerance status and survival: the Rancho Bernardo Study. J Intern Med 2010. Objectives., Little is known about uric acid (UA) levels and mortality in the context of glycaemia. We examined whether serum UA levels predict all-cause and cardiovascular disease (CVD) mortality differentially in older adults by glucose tolerance status. Design and methods., Between 1984 and 1987, 2342 community-dwelling men and women had an oral glucose tolerance test, UA measurement, and assessment of traditional CVD risk factors. We defined glucose tolerance status as normoglycaemia (NG), pre-diabetes (pre-DM), and type 2 diabetes mellitus (T2DM). Ninety per cent were followed for vital status up to 23 years. Death certificates were coded using the Ninth International Classification of Diseases. Results., Baseline age was 69.5 years; 44.4% were men. At baseline 939 had NG, 957 pre-DM, and 446 T2DM. The mean UA by glucose tolerance status was 327.1, 362.8, and 374.7 ,mol L,1. During follow-up, there were 1318 deaths 46.8% attributed to CVD. In Cox-regression analysis, each 119 ,mol L,1 (2 mg dL,1) increment in UA levels predicted an increased hazard ratio (HR) for all-cause deaths independent of age, smoking, body mass index, alcohol, physical activity, diuretic use and estimated glomerular filtration rate in all groups (NG: HR 1.25 95% CI 1.06,1.47, P =0.005; pre-DM: HR 1.20 95% CI 1.06,1.37, P = 0.04; T2DM: HR 1.20 95% CI 1.01,1.47, P = 0.04). After adjusting for CVD risk factors, the UA association with CVD mortality was significant only in the pre-DM and T2DM groups. Conclusion., All-cause mortality was independently associated with UA in all groups, but UA predicted CVD mortality only in those with abnormal glucose tolerance. [source] Measurement of HIV RNA in patients infected by subtype C by assays optimized for subtype B results in an underestimation of the viral loadJOURNAL OF MEDICAL VIROLOGY, Issue 2 2004Bat-Sheva Gottesman Abstract Quantitation assays of HIV-1 RNA used currently were designed and optimized for subtype B viruses. However, infection with non-B HIV viruses has become more common worldwide. Unfortunately, little information is available regarding the suitability of these assays for measurement of viral load in specific non-B subtypes. The performance of two commercial HIV-1 RNA quantitation assays was evaluated in 82 HIV subtype C-infected patients and in 43 HIV-1 subtype B-infected patients. Blood samples were tested by the Amplicor HIV-1 Monitor Assay, Version 1.5, and by the nucleic acid sequence-based amplification HIV-1 assay (NucliSens). The results were compared by using a paired, two-tailed Student's t -test; the difference between the assays was found to be significant only for subtype C. Discordant results (>0.5 log difference) between the two assays were detected in 39% of subtype C samples, compared to 23.2% of subtype B samples. In all cases in which a discordant result was detected, the lower results were obtained by the NucliSens assay. Discordant results between CD4 and viral load (CD4,<,200 cells/ml with a viral load <5,000 copies/ml) were observed in eight of the subtype C-infected patients when a viral load was measured by NucliSens (9.7%), compared to three patients (3.6%) when measured by the Amplicor assay. In conclusion, in patients with HIV subtype C infection, measurement of HIV RNA by the NucliSens assay resulted in a significant underestimation of the viral load as compared to the Amplicor assay. As a consequence, such an underestimation may result in sub-optimal care of patients infected with HIV subtype C. J. Med. Virol. 73:167,171, 2004. © 2004 Wiley-Liss, Inc. [source] Variety-specific Epidemiology of Cercospora beticola Sacc. and Consequences for Threshold-based Timing of Fungicide Application in Sugar BeetJOURNAL OF PHYTOPATHOLOGY, Issue 4 2010Ulrike Kaiser Abstract In Central Europe, fungicides to control leaf spot disease in sugar beet caused by Cercospora beticola are applied based on thresholds of disease incidence (DI, per cent of infected plants). As variety-specific fungicide application was not analyzed to date, the epidemiology of C. beticola and its effect on white sugar yield (WSY) in varieties with different susceptibility were investigated at seven sites in Germany and Austria in 2004 and 2005. All varieties reached the summary thresholds 5 / 15 / 45% DI in all environments. Fitting a logistic growth curve to DI revealed significant differences among varieties. At high disease pressure, susceptible varieties reached a considerably higher disease severity (DS, per cent of infected leaf area) at harvest and a larger area under disease progress curve (AUDPC) than resistant varieties. Fitting a logistic growth curve to DS showed an increasing differentiation among varieties with time. The growth rate estimated based on the logistic growth curve was the only variable that performed equally well in differentiating varieties under low and high disease pressure. With increasing disease pressure, varieties differed considerably in WSY, but differences between susceptible and resistant varieties were significant only in some environments. The disease-loss relation between AUDPC and relative WSY was variety-specific. Resistant varieties had an approximately identical WSY with and without infection and compensated for negative infection effects even at higher AUDPC. Therefore, at high disease pressure, resistant varieties had a higher relative yield compared to susceptible ones. However, our results indicate that there is no need to develop variety-specific thresholds, but resistant varieties reach the established thresholds later than susceptible ones. Consequently, the time of fungicide application can be delayed in resistant varieties. This will help to reduce the use of fungicides to the bare essentials as requested for the integrated crop protection management. [source] Assessment of predictors of global self-ratings of oral health among Korean adults aged 18-95 yearsJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 3 2010Hae-Young Kim DDS Abstract Objectives: The aims of this study were to assess predictors of global self-ratings of oral health (GSROH) and to examine whether they varied by age among Korean adults aged 18-95 years. Methods: Data from 4,546 adults aged 18-95 years completing the Korean National Oral Health Survey 2006 were included in the analysis. Results: Subjects' mean age was 43.5 years, with 12.1 percent aged ,65 years; 47.8 percent were men; and 2.5 percent were edentulous. The predictors of GSROH in adults were number of missing teeth, concern about oral health, and difficulty in chewing. While wearing removable dentures was associated only in elders, perceived treatment need was associated in younger age groups. The number of decayed and filled teeth was significant only in the 18-44 age group. Conclusions: GSROH status was associated with measures of oral disease, oral functional problems, oral health behaviors, concerns, and perceived treatment needs, and it varied by age. [source] Impact of Age at First Drink on Stress-Reactive DrinkingALCOHOLISM, Issue 1 2007Deborah A. Dawson Background: Although recent data from animal models indicate that adolescent ethanol exposure increases self-administered ethanol intake in adult rats, the impact of age at first drink on the association between stress and drinking has not been studied in humans. Methods: Data collected in the 2001 to 2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were used to estimate the extent to which age at first drink modified the association between stress and average daily volume (ADV) of ethanol intake in a sample of 26,946 past-year drinkers. Successive models estimated the magnitude and significance of the interaction between age at first drink (ages 14 or younger, 15,17, and 18 or older) and number of stressors (out of 12 past-year negative life events) after (1) adjusting for sociodemographic characteristics, (2) additionally adjusting for family history of alcoholism, comorbid psychopathology, adolescent, and past-year tobacco and illicit drug use, and (3) additionally adjusting for all other significant interactions with number of stressors. Results: Even after adjusting for a wide range of confounders and their interactions with stress, initiation of drinking at ages 14 and younger increased the association between the number of stressors and ADV of ethanol consumption by 8% (p=0.014), when considering the full range of 12 potential stressors. In fact, the positive association between stress and consumption was significant only for this group of drinkers with early adolescent exposure to ethanol. Within this group, ADV of consumption increased by an average of 7% with each additional stressor experienced, although the exact percentage increase varied as a function of other covariates that had significant interactions with stress. When a reduced set of 4 stressors was considered, the magnitudes of the associations were mostly unchanged, but the modifying effect of age at first drink fell short of statistical significance (p=0.309) in the fully adjusted model. Conclusions: The findings of this study are consistent with the argument that early-onset drinking may increase stress-reactive ethanol consumption; however, these findings need to be replicated in an experimental human study in order to control fully the direction of the relationship between stress and consumption. [source] Age-related change in the association between a polymorphism in the PER3 gene and preferred timing of sleep and waking activitiesJOURNAL OF SLEEP RESEARCH, Issue 1 2007KAY H. S. JONES Summary The objective of this study was to investigate the effect of age on the association between preferred timing of sleep and waking activities and a coding-region variable number tandem repeat (VNTR) polymorphism in the clock gene PER3. We have previously reported this polymorphism to associate with diurnal preference and delayed sleep phase syndrome (DSPS). Participants (n = 1590; 707 males and 883 females) completed the Horne,Östberg (HÖ) questionnaire for diurnal preference and provided a DNA sample. Overall HÖ scores were plotted against age. The 5% extremes and intermediates were selected for genotyping. Frequencies of the PER3 4- and 5-repeat alleles were examined in separate age groups (18,29, 30,39, 40,49 and 50+ years of age). The 4-repeat allele was significantly more frequent in evening types, and the 5-repeat allele more frequent in morning types (Fisher's exact test, P = 0.016). Analysis in the four age groupings revealed that the strength of this association attenuated with age and was significant only in the youngest group (18,29 years). These results extend our previous finding of an association between the PER3 VNTR and diurnal preference. They also demonstrate that diurnal preference in young people is more closely associated with this polymorphism than it is in other age groups. [source] Kinetic Simulations of Reversible Chain Transfer Catalyzed Polymerization (RTCP): Guidelines to Optimum Molecular Weight ControlMACROMOLECULAR THEORY AND SIMULATIONS, Issue 1 2010Philipp Vana Abstract Kinetic simulations of reversible chain transfer catalyzed polymerization (RTCP) were performed using the program package Predici. Mimicking the RTCP of styrene in bulk at 80,°C, the full molecular weight distributions, the polydispersities of resulting polymer and the time evolutions of monomer conversion and participating species were simulated. The influence of the kinetic coefficients governing the RTCP equilibrium , specifically, the rate coefficients of activation, ka, and deactivation, kda , on the controlled polymerization behavior was probed in detail by varying their respective simulation input values over five orders of magnitude. It was found that optimum results for molecular weight control are obtained for K,=,ka/kda in the range 1 to 10 and with ka and kda being of the order of 106 L,·,mol,1,·,s,1 or above. The influence of degenerative chain transfer on the process was found to be significant only in poorly controlled systems, but is small in well-controlled RTCP. Based on the finding that the catalyst is depleting during the polymerization due to cross-termination, guidelines for obtaining high molecular weight material via repeated addition of catalyst were developed. [source] The impact of climate variability on soybean yields in Argentina.METEOROLOGICAL APPLICATIONS, Issue 1 2007Multivariate regression Abstract Climate variability is examined and discussed in this work, emphasizing its influence over the fluctuation of soybean yield in the Pampas (central-eastern Argentina). Monthly data of rainfall, maximum and minimum temperatures, thermal range and seasonal rainfall were analysed jointly with the soybean yield in the period 1973-2000. Low-frequency variability was significant only in the minimum temperature during November in almost all the stations. This situation is favourable to the crop since during this month, seed germination, a growth stage sensitive to low temperatures, takes place. In the crop's core production region, 72% of the series of soybean yield presented a positive trend. Except in years with extreme rainfall situations, interannual variability of the soybean yield is in phase with the seasonal rainfall interannual variability. During these years, losses in the soybean crop occurred, with yield negative anomalies greater than one standard deviation. Soybean yield showed spatial coherence at the local scale, except in the crop's core zone. The association between each climate variable and yield did not show a defined regional pattern. Summer high temperature and rainfall excesses during the period of maturity and harvest have the greatest negative impact on the crop, whilst higher minimum temperatures during the growing season favour high yields. The joint effect of climate variables over yield was studied with multivariate statistical models, assuming that the effect of other factors (such as soil, technology, pests) is contained in the residuals. The regression models represent the estimates of the yield satisfactorily (high percentage of explained variance) and can be used to assess expected anomalies of mean soybean yield for a particular year. However, the predictor variables of the yield depend on the region. Copyright © 2007 Royal Meteorological Society [source] | ||||||||||||||||||||||||||||||||||||||||||||||