bluuebunny/crossref_metadata_2025 huggingface dataset:
Second and third harmonic generations in random composites of spheroidal particles
Authors: Liu Bo , Gao Lei
Published: February 2005

With the aid of the spectral representation and decoupling approximation, we investigate the effective optical susceptibilities for second harmonic generation (SHG) and third harmonic generation (THG) of nonlinear composites media, in which the nonlinear spheroidal particles are embedded in a linear host medium. We emphasize the effect of the granular shape on SHG and THG susceptibilities in two types of microstructures corresponding to those described by the generalized Maxwell–Garnett Theory (MGT) and Effective Medium Approximation (EMA). Numerical results show that large enhancement of SHG and THG can be achieved by the adjustment of the depolarization factor (or the granular shape). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence and defects creation in Ce3+‐doped YAlO3 and Lu0.3Y0.7AlO3 crystals
Authors: Blazek K. , Krasnikov A. , Nejezchleb K. , Nikl M. , Savikhina T. , Zazubovich S.
Published: February 2005

Luminescence, energy transfer and defects creation processes were studied for the Ce3+‐doped YAlO3 and LuxY1–xAlO3 (x = 0.3) crystals in the temperature range 4.2–300 K under selective photoexcitation in the energy range 3.5–11.5 eV. For the first time, defects creation spectra were measured and analyzed. Influence of the charge and ionic radii of co‐doping ions on the luminescence and defects creation efficiency was considered. The origin of the defects created and possible mechanisms of their formation were discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
SO phonons in spherical nanostructured quantum dots
Authors: Comas F. , Odriazola A.
Published: February 2005

A theoretical model for a nanostructured spherical Quantum Dot (QD) is considered, where to a core sphere of semiconductor “1” it is added a concentric spherical layer of semiconductor “2”, while this structure is assumed as imbedded in an infinite medium made of semiconductor “1”. Using a long‐wave continuum approach, the so‐called dielectric continuum approach, we study the surface optical (SO) phonons associated with the two spherical interfaces of the nanostructure. The possible SO phonon frequencies are analyzed as a function of both the sizes of the structure and the angular momentum quantum number l = 1, 2, …. We also calculate the electric potential provided by the SO phonons and derive an analytical expression for the electron–phonon interaction Hamiltonian. Different possible cases for semiconductors “1” and “2” are discussed, comparisons with previously published works on similar subjects are done and the experimental techniques allowing the possible determination of this kind of phonons are invoked. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of experimental noise on densities reconstructed from line projections
Authors: Samsel‐Czekała M. , Boguszewicz Ł.
Published: February 2005

The influence of experimental noise on densities ρ(p) reconstructed by the Cormack method from their line projections, e.g. 2D ACAR spectra, is investigated. Simulations of statistical noise are performed for various sets of 2D spectra for two model ρ(p) having the cubic symmetry. For the reconstructed densities propagation of the statistical error in terms of standard deviations, σ[ρ(p)], is estimated. We observe that the distribution of σ[ρ(p)] has its extremes along the main symmetry directions and also a tendency to accumulate for small p. Moreover, the more density components, ρn(p), have to be taken to description of ρ(p) the less anisotropic is the distribution of σ[ρ(p)]. Additionally, the error generated by the reconstruction method itself is discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ab initio QM/MM study of excited state electron transfer between pyrene and 4,4′‐bis(dimethylamino)‐diphenylmethane with different solvent systems: Role of hydrogen bonding within solvent molecules
Authors: Sen Kakali , Basu Samita , Bhattacharyya Dhananjay
Published: February 2005

The exciplex is a charge transfer species formed in the process of electron transfer between an electron donor and an electron acceptor and hence is very sensitive to solvent polarity. In order to understand the role of solvent in exciplex formation between pyrene (PY) and 4,4′‐bis(dimethylamino)diphenylmethane (DMDPM), we used two types of solvent approximations: an implicit solvent model and an explicit solvent model. The difference in energies between the excited and the meta‐stable Frank–Condon state (ΔE) of the structures were assumed to correspond to the emission maximum of the exciplex in different solvents. The ΔE values show the trend of stabilization of the exciplex with an increase in solvent polarity. This trend in stabilization is substantially more prominent in the explicit solvent model than that with the implicit solvent model. The ΔE value obtained in methanol reflects equal stabilization compared to that in a more polar solvent, N,N‐dimethylformamide. This extra stabilization of the exciplex may be explained on the basis of the H‐bonding capability of the protic solvent, methanol. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Jahn–Teller theorem and nodal points of wave functions
Authors: Pupyshev Vladimir I.
Published: February 2005

The split of electronic energy levels for a degenerate state near the symmetrical geometry configuration is considered. It is demonstrated that this effect is closely connected with the nodal properties of the symmetry‐adapted orbitals. Simple proof of the Jahn–Teller theorem is proposed based on analysis of the “radial” vibrations (Zhilinskii–Stepanov theorem). Examples of “violations” of the Jahn–Teller theorem are considered. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Properties of methanol bound to a defect of zeolitic structure
Authors: Stepanov Nikolai F. , Kubasov Alexei A. , Tikhii Yaroslav V.
Published: February 2005

Different mechanisms of Brønsted acidity formation upon the adsorption of a methanol molecule on a model Lewis acid site within zeolitic structure are evaluated by means of density functional theory in cluster approximation. The properties of the Brønsted acid sites formed are examined through studying their interaction with such probe molecules as methanol, ammonia, and ethylene. The results obtained are used to comment on a possible role of Lewis acid sites in methanol reactions catalyzed by zeolites. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Resonance Raman and hyper‐Raman spectroscopy of organic chromophores for second‐order nonlinear optics
Authors: Myers Kelley Anne
Published: February 2005

Two‐photon resonant hyper‐Raman spectroscopy from large molecules in solution is discussed as a method for probing excited electronic states that are both one‐ and two‐photon allowed. A number of electron donor–acceptor substituted conjugated organic molecules that have large first hyperpolarizabilities (β) have recently been shown to give strong resonance hyper‐Raman (RHR) spectra in solution. The quantum mechanical formulation of RHR scattering is reviewed, and practical approaches to calculating RHR spectra and excitation profiles are proposed by reference to methods already developed for simulating linear resonance Raman spectra and profiles. The potential benefits of a close interplay between experiments, empirical simulations, and electronic structure calculations of ground‐state and excited‐state properties are emphasized. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Infrared linear dichroism in stretched films: Quantum mechanical approach within the polarizable continuum model
Authors: Cappelli Chiara , Corni Stefano , Mennucci Benedetta , Tomasi Jacopo , Cammi Roberto
Published: February 2005

In this work we discuss how environmental effects on vibrational transition moment directions for molecules dispersed in stretched films can be accounted for via the integral equation formalism polarizable continuum model (IEFPCM). In particular, effects related to the matrix polarization induced by the probing field (cavity field terms) are taken into account. Calculations are performed for three DNA‐related molecules (9‐methyladenine, 7‐methyladenine, and 2‐amino‐9‐methylpurine) for which infrared linear dichroism (IR LD) has been measured experimentally. By combining experimental data and calculations, different parameters of the film (Saupe order parameters and orientational axis direction) can be obtained and used to give “experimental” estimates of transition moment directions. The results show the importance of accounting for the environment surrounding the molecule in transition moment calculations. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Design and performance of a sheathless capillary electrophoresis/mass spectrometry interface by combining fused‐silica capillaries with gold‐coated nanoelectrospray tips
Authors: Kele Zoltán , Ferenc Györgyi , Klement Éva , Tóth Gábor K. , Janáky Tamás
Published: February 2005

A simple sheathless capillary electrophoresis (CE)/mass spectrometry (MS) interface was constructed by combining widely used nanospray needles with fused‐silica capillaries and it was successfully applied for the separation of peptides. The end of the CE capillary was pulled to a taper, etched and then fitted into the metal‐coated nanospray borosilicate capillary. The nanospray needle can be used for several CE runs, but it can be easily and rapidly changed in the case of accidental breakage or evaporation of the coating. A fast capillary electrochromatographic method was also developed for MS analysis of peptides containing numerous basic amino acids. Copyright © 2005 John Wiley & Sons, Ltd.
Regression models for the analysis of longitudinal Gaussian data from multiple sources
Authors: O'Brien Liam M. , Fitzmaurice Garrett M.
Published: February 2005

We present a regression model for the joint analysis of longitudinal multiple source Gaussian data. Longitudinal multiple source data arise when repeated measurements are taken from two or more sources, and each source provides a measure of the same underlying variable and on the same scale. This type of data generally produces a relatively large number of observations per subject; thus estimation of an unstructured covariance matrix often may not be possible. We consider two methods by which parsimonious models for the covariance can be obtained for longitudinal multiple source data. The methods are illustrated with an example of multiple informant data arising from a longitudinal interventional trial in psychiatry. Copyright © 2005 John Wiley & Sons, Ltd.
Familiarity may buffer the adverse effects of relocation on marmosets (Callithrix kuhlii): Preliminary evidence
Authors: Schaffner C.M. , Smith T.E.
Published: February 2005

The relocation of exotic species is increasingly crucial for the proper management of captive populations. We investigated the effects of relocation on urinary cortisol levels and proximity behavior in four Wied's marmosets (Callithrix kuhlii). Two of the relocated marmosets constituted a well‐established pair, whereas two (the newly established pair) were introduced when they arrived at the new facility. Four adult females served as control animals in which we assessed cortisol response to pair formation in the absence of relocation. Urinary cortisol in the relocated subjects was monitored for 4 weeks before and 12 weeks after the relocation event. Urinary cortisol in the control subjects was monitored for 4 weeks before and 8 weeks after the pairs were formed. Proximity was monitored in the relocated subjects for 12 weeks following the move. After the animals were relocated, the newly established pair had significantly elevated levels of urinary cortisol compared to the well‐established pair and control females, which lasted at least 8 weeks. For both pairs, cortisol levels decreased over time across the 12 weeks following the relocation event. The members of the well‐established pair were in contact with each other for 65% of the intervals sampled in the 2 weeks immediately following relocation, compared to only 12% in the newly established pair. These preliminary findings suggest that relocation is associated with significant adverse physiological and behavioral changes that may be ameliorated by the presence of a highly familiar social partner. The study highlights the importance of future research in this field. Zoo Biol 24:93–100, 2005. © 2005 Wiley‐Liss, Inc.
Predicting reproduction in captive sea otters (Enhydra lutris)
Authors: Da Silva I.M. , Larson S.
Published: February 2005

The sea otter (Enhydra lutris) is a threatened species. It is also a popular exhibit animal in many zoos and aquariums worldwide. Unfortunately, sea otters reproduce successfully in only a small number of facilities. Pregnancies vary in duration, and are thought to involve a delayed implantation of about 2–3 months, followed by an implanted phase of 4–5 months. In this study we attempted to identify estrus and pregnancy states, and predict the date of birth in one female sea otter (Mali) housed at the Lisbon Oceanarium. We used different techniques to evaluate her reproductive status, including monitoring behavior to determine estrus, assessing weight changes to determine pregnancy and parturition date, and analyzing fecal hormone samples to determine estrus, pregnancy, and parturition date. During this study, Mali became pregnant four times. Her gestational length varied between 188–255 days. Weight increases >29 kg or 15% above baseline weight suggested pregnancy, and parturition was estimated to occur approximately 3 months thereafter. Fecal hormone (progestagens and estrogen) metabolite data gathered during two of her pregnancies showed that Mali's delayed implantation phase of pregnancy lasted 43–109 days (a typical duration in other sea otters is 100–110 days). Mali's implanted phase lasted a relatively long time (140–145 days compared to an average of 117 days in other sea otters). The combination of the three measurements was a powerful tool that enabled us to determine pregnancy and anticipate the arrival of a new sea otter pup. Zoo Biol 24:73–81, 2005. © 2005 Wiley‐Liss, Inc.
Energy and mineral nutrition and water intake in the captive Indian rhinoceros (Rhinoceros unicornis)
Authors: Clauss Marcus , Polster Carmen , Kienzle Ellen , Wiesner Henning , Baumgartner Katrin , von Houwald Friedericke , Streich W. Juergen , Dierenfeld Ellen
Published: February 2005

In the captive Indian rhinoceros (Rhinoceros unicornis), two disease complexes with a high incidence—chronic foot problems and uterine leiomyomas—may be linked to excess body weight (BW). In this study, intake and digestion trials were conducted (by means of 7‐day weigh‐backs, and 5‐day total fecal collections, respectively) with 11 Indian rhinoceroses at four zoological institutions in Europe and the United States to quantify energy and mineral nutrition on conventional or roughage‐only diets. Diets comprising a variety of forages (grass hay only, a combination of grass hay and grass silage, straw, or a mixture of grass and legume hay) were offered as the roughage source, along with various concentrates, produce, and supplements. Water intake was quantified, and urine samples were obtained opportunistically. The animals consumed 0.5–1.1% of their BW in dry matter (DM) daily, with calculated digestible energy (DE, in megajoules MJ) values ranging from 0.27 to 0.99 MJ DE/kg BW0.75/day compared to an estimated requirement of 0.49–0.66 MJ DE/kg BW0.75/day. Seven of 11 rhinos (64%) fed restricted levels of concentrate plus forage consumed DE in excess of this estimate. Even on roughage‐only diets, some individuals consumed energy well above the presumed metabolic requirements. Hence, restriction of both concentrates and roughage may be important for weight management in this species. Water intake ranged from 30 to 49 mL/kg BW daily (3.4–5.2 L/kg ingested DM), similar to values that have been reported for domestic equids. Excretion amounts and patterns also resembled those found in horses. Endogenous fecal losses measured for Ca, P, Cu, Fe, and Zn indicate that the maintenance requirements of these minerals should be met in Indian rhinoceroses by diets that meet recommendations for domestic horses. It is particularly important to evaluate dietary adequacy in mineral nutrition in this species in concert with the need for restricted energy intake, especially with regard to the hypothetical involvement of a low Zn supply in chronic foot problems. Zoo Biol 24:1–14, 2005. © 2005 Wiley‐Liss, Inc.
Fecal corticoid monitoring in whooping cranes (Grus americana) undergoing reintroduction
Authors: Hartup Barry K. , Olsen Glenn H. , Czekala Nancy M.
Published: February 2005

We used radioimmunoassay to determine fecal corticoid concentrations and assess potential stress in 10 endangered whooping cranes (Grus americana) undergoing reintroduction to the wild. Fecal samples were collected shortly after hatching at a captive facility in Maryland, during field training in Wisconsin, and throughout a human‐led migration to Florida. After a 14‐day decline following hatching, fecal corticoid concentrations stabilized at baseline levels for the duration of the captive period, despite exposure to potentially stressful stimuli. Shipment of the cranes to the field training site was correlated with an eight‐ to 34‐fold increase in fecal corticoid concentrations, which returned to baseline levels within 1 week. Increases were positively correlated with age but not body weight at the time of shipping. Fecal corticoid concentrations during the training period increased slightly and exhibited greater variation than levels observed at the captive facility, but were well within expected norms based on previous studies. Fecal corticoid concentrations increased twofold following premigration physical examinations and placement of radiotransmitters, and persisted for up to 4 days before they returned to baseline levels. Though fecal corticoid concentrations and variation during the migration period were similar to training levels, there was an overall decline in fecal corticoid concentrations during the artificial migration. Acute stressors, such as capture, restraint, and severe storms, were associated with stress responses by the cranes that varied in accordance with lasting physical or psychological stimuli. The overall reintroduction process of costume‐rearing, ultralight aircraft habituation, training, and artificial migration was not associated with elevations in fecal corticoid concentrations suggestive of chronic stress. Zoo Biol 24:15–28, 2005. © 2005 Wiley‐Liss, Inc.
Reproduction, Growth and Development in Captive Beluga (Delphinapterus leucas)
Authors: Robeck Todd R. , Monfort Steven L. , Calle Paul P. , Dunn J. Lawrence , Jensen Eric , Boehm Jeffrey R. , Young Skip , Clark Steven T.
Published: February 2005

Recent success propagating captive beluga has resulted from combined efforts by North American zoos and aquariums to manage disparate collections as a single population. This success has provided a tremendous opportunity to increase our understanding of beluga reproductive biology. Blood samples were collected on a weekly to biweekly basis from 23 female and 12 male beluga, ranging in age from 2–15 years, for analysis of serum progesterone (P) and testosterone (T), respectively. Peri‐parturient observational data, including food intake, duration and signs of labor, and nursing patterns were collected from 15 days prepartum to 30 days postpartum during 21 births. Total body lengths and weights were collected from 10 captive‐born beluga. For female beluga, the mean (±SD) age, body length, and weight at first conceptions were 9.1±2.8 years, 318.0±9.1 cm, and 519±84 kg. Thirty‐five luteal phases and 13 conceptions were detected from January–June, and 70% of luteal phases and 80% conceptions occurred from March–May. The mean luteal phase and total estrous cycle lengths were 30.0±6.5 days and 48.0±4.6 days, respectively. For male beluga, the mean age that males sired their first calf was 13.3±2.6 years. Compared to younger males (<8 years of age, 0.95 ng/ml), levels of T secretion in older males (>8 years of age, 5.0 ng/ml) were elevated significantly only during the interval from January–April. Highest T concentrations (6.2±4.9 ng/ml) were recorded from January–March, whereas nadir concentrations (1.1±1.0 ng/ml) were detected from August–September. The mean gestation length was 475.0±20.4 days (n=9). For parturition, the mean time from the first appearance of fluke or rostrum to delivery, delivery to placental passage, and delivery to nursing were 4.4±2.9 hr, 7.6±1.8 hr, and 43±45 hr, respectively. All cows had decreased food intake on the day of delivery, with 44% having zero intake. Peak 24‐hr nursing activity occurred 3.9±2.7 days post‐partum. Growth (i.e., body weight and length) as a function of age were well described by the Gompertz model (r2=0.91, 0.93). Based on the model, growth in body weight and length were significantly greater in males compared to females. Predicted birth weight (88.9 kg) was similar for both sexes, however, and male calves were predicted to be shorter (154.3 cm) than female calves (160.7 cm). The results provide the first descriptions of captive beluga reproductive physiology, including endocrinology, peri‐parturient behavior, growth, and reproductive maturity. This knowledge is important for helping to maintain genetically diverse, self‐sustaining populations of captive beluga whales. Zoo Biol 24:29–49, 2005. © 2005 Wiley‐Liss, Inc.
Mineral concentrations in serum/plasma and liver tissue of captive and free‐ranging Rhinoceros species
Authors: Dierenfeld Ellen S. , Atkinson Shirley , Craig A. Morrie , Walker Karen C. , Streich W. Jürgen , Clauss Marcus
Published: February 2005

Mineral implications in health issues of captive rhinos have received much attention lately. This study was undertaken to establish reference values for the mineral status of rhinos. Serum/plasma samples of free‐ranging black (Diceros bicornis) and white (Ceratotherium simum) rhinos and of captive black, white, Indian (Rhinoceros unicornis), and Sumatran (Dicerorhinus sumatrensis) rhinos, as well as liver tissue samples of captive black, white, and Indian rhinos were analyzed for mineral content. Circulating mineral levels of free‐ranging animals were subject to variation according to region. In free‐ranging animals, high molybdenum (Mo) values compared to horse normals were striking. Captive animals displayed even higher circulating Mo concentrations. The significance of iron (Fe) overload in captive specimens of the browsing rhinos (black and Sumatran) was confirmed. Hepatic Fe levels increased in blacks with age. Although this Fe overload is suspected to be linked with diets, the data indicate that this is not due solely to an excessive dietary Fe supply. Whereas the grazing species (white and Indian) had high liver copper (Cu) levels, the browsing species had low to marginal liver Cu concentrations. Liver concentrations of K, Mg, Co, and Mo increased with age in captive black rhinos. Additional findings include high circulating Se levels in all rhino species. Future research should be directed at investigating factors leading to high Fe levels, and at investigating Cu metabolism in captive rhinoceros species. Zoo Biol 24:51–72, 2005. © 2005 Wiley‐Liss, Inc.
Surgery for Esophageal Cancer after Concomitant Radiochemotherapy: Oncologic and Functional Results
Authors: Plaisant Nicolas , Senesse Pierre , Azria David , Lemanski Claire , Ychou Marc , Quenet Francois , Saint‐Aubert Bernard , Rouanet Philippe
Published: February 2005

The aim of this study was to evaluate the results of surgery after preoperative radiochemotherapy (PRCT) for esophageal cancer. This retrospective study included 88 patients scan between 1992 and 2000. The median follow‐up was 55.7 months (3.3‐104.1 months). Surgical mortality was 15.9%. Multivariate analysis found that the following were risk factors for surgical mortality: γ‐glutamyltransferase level > 75 UI/ml (p= 0.007), weight loss = 10% (p= 0.05), and digestive toxicity World Health Organization grade III or IV during PRCT (p= 0.019). The median overall survival was 24.9 months. The 5‐year overall survival (OS) and disease‐free survival (DFS) were, respectively, 33.1% and 33.2%. Complete responder patients had a 71.8% 5‐year OS (p= 0.01) and a 71.8% 5‐year DFS (p= 0.009). The rate of recurrence was 37.5%. Multivariate analysis found that female gender (p= 0.03), weight loss = 10% (p= 0.03), preoperative computed tomography scan bronchial contact (p= 0.01), and N+ status (pN+) at pathology examination (p= 0.0001) were predictors of poor oncologic results. Patients with high preoperative risk of surgical mortality need to be selected for intensive perioperative management. In association with surgery, PRCT improves the local control, DFS, and OS of responder patients. Morphologic evaluation for staging esophageal cancer in predicting the pathologic response after PRCT is poor or controversial. Only surgical resection can provide accurate prognostic information for staging esophageal cancer and improving local control.
Intravenous Contrast‐enhanced Computed Tomography in the Diagnosis of Acute Appendicitis
Authors: Iwahashi Naoko , Kitagawa Yoshimi , Mayumi Toshihiko , Kohno Hiroshi
Published: February 2005

This study evaluated the usefulness of routine, nonfocused intravenous contrast‐enhanced computed tomography (CT) in diagnosing acute appendicitis. Also evaluated was the diagnostic value of several findings that were clinically associated with acute appendicitis. Although a number of studies have shown various techniques using CT to be accurate in the diagnosis of acute appendicitis, few studies have focused on CT with using only intravenous contrast material. Computed tomography scan criteria for acute appendicitis have been established chiefly on the basis of appendiceal findings. We, on the other hand, have often observed the following associated conditions during appendectomy: ascites, paresis of the intestine, or thickening of adjacent tissues. In this study, we reviewed the intravenous contrast‐enhanced CT scans of 78 patients who had been diagnosed as having acute appendicitis and had subsequently undergone surgery. We also compared the CT scans with patients’ surgical and histological findings. As a way of evaluating clinical ancillary signs, we identified and analyzed individual CT findings that included abnormal appendix, calcified appendicolith, ascites, dilated intestine, and cecal wall thickening. The sensitivity, specificity, and accuracy of intravenous contrast‐enhanced CT in surgical cases were found to be 91.9%, 87.5%, and 91.0%, respectively. Individual findings except for abnormal appendix were not significantly common among patients who had acute appendicitis. However, more positive findings were observed in patients who had appendicitis than in those who had normal appendixes. Intravenous contrast‐enhanced CT scan is a useful technique in the diagnosis of acute appendicitis. The plurality of ancillary signs in CT scans also appears to be a helpful indicator in the diagnosis of acute appendicitis.
The Evaluation of Duct‐to‐mucosal Pancreaticojejunostomy in pancreaticoduodenectomy
Authors: Tani Masaji , Onishi Hironobu , Kinoshita Hiroyuki , Kawai Manabu , Ueno Masaki , Hama Takashi , Uchiyama Kazuhisa , Yamaue Hiroki
Published: February 2005

This study was conducted to examine the efficacy of duct‐to‐mucosal pancreaticojejunostomy compared with external stented pancreaticojejunostomy in prevention of several complications, retrospectively. Seventy‐six patients with pancreatic head resection (59 male; median age, 60.1 years) underwent pancreaticoduodenectomy at the Second Department of Surgery, Wakayama Medical University, School of Medicine, Wakayama, Japan, between January 1, 1994, and March 31, 2002. In early postoperative status, the incidence of pancreatic fistula by duct‐to‐mucosal anastomosis (n = 45) was similar to that by external stent (n = 31); soft pancreas is a risk factor of pancreatic fistula compared with hard pancreas (p < 0.05). During the late postoperative period, however, no patients with duct‐to‐mucosal anastomosis showed pancreatic duct dilatation by computed tomography (CT). At the same time, 58.8% of patients with external stent followed by CT showed pancreatic duct dilatation (p < 0.01). The duct‐to‐mucosal anastomosis was more effective pancreaticojejunostomy than the external stent in terms of prevention of pancreatic duct dilatation, and it should be the surgical procedure of choice in pancreaticoduodenectomy.
Female adolescents with anorexia nervosa and their parents: a case-control study of exercise attitudes and behaviours
Authors: DAVIS CAROLINE , BLACKMORE ELIZABETH , KATZMAN DEBRA K. , FOX JOHN
Published: February 2005

Background. Few studies of physical activity in patients with anorexia nervosa (AN) have included a suitable control group. Nor has such research considered the influence of parents' activity on that of their children. Our first prediction was that adolescents with AN would be significantly more active than healthy controls both prior to, and during, the progression of their disorder. We also expected that the activity levels of parents and their daughters would be correlated, and that this relationship would be stronger in patient than control families. Finally, we expected that the AN parents would be more active and report a greater commitment to exercise than the control parents.

Method. In a case-control design, we employed multiple indicators of physical activity from adolescent females and their parents, using longitudinal, retrospective, self-report measurements.

Results. AN patients were significantly more active than controls both during the course of their disorder and prior to its onset. Parents' activity related to their daughter's activity, but this relationship was not stronger in the parents of the patients.

Conclusions. Future research is needed to determine whether the relationship between parents' and children's activity levels reflects environmental or genetic influences, or a combination of both factors. The important observation of a significant increase in patients' activity levels at least a year prior to diagnosis of the disorder suggests that enhanced physical activity may play a role in the development of the disorder. This may also serve as an early warning sign of a subclinical eating disorder in adolescent girls.
Early increase in vegetative symptoms predicts IFN-α-induced cognitive-depressive changes
Authors: WICHERS M. C. , KOEK G. H. , ROBAEYS G. , PRAAMSTRA A. J. , MAES M.
Published: February 2005

Background. The vegetative symptoms of depression resemble the symptoms of malaise associated with activation of the inflammatory response system (IRS), and can be regarded as an expression of a central motivational state that resets the organism's priorities to promote recovery from infection. Early vegetative symptoms, however, may also contribute to the high rates of depression seen later in the course of immune activation. We hypothesized that the onset of vegetative-depressive symptoms early in the treatment with the pro-inflammatory cytokine IFN-α in chronic hepatitis C patients would increase the risk for subsequent depressive cognitions.

Method. Sixteen patients eligible for IFN-α treatment and free of psychiatric disorders were recruited. The DSM-IV, the Multidimensional Fatigue Inventory, and the Montgomery–Asberg Depression Rating Scale (MADRS) were administered at baseline and 1, 2, 4, 8, 12 and 24 weeks after treatment was initiated. Cognitive-depressive and vegetative-depressive symptom clusters were constructed.

Results. Fatigue and depression scores increased significantly during IFN-α treatment. Depression scores were highest at week 8 of treatment. First week increase in vegetative-depressive symptom score predicted cognitive-depressive symptom score at week 8 and at week 24.

Conclusions. During IFN-α treatment, vegetative symptoms of depression appear earlier than, and are predictive of, their cognitive counterparts. This finding suggests that low mood state may in part be driven by the increase in early vegetative-depressive symptoms in the course of IFN-α-induced immune activation.
The changing impact of a severe disaster on the mental health and substance misuse of adolescents: follow-up of a controlled study
Authors: REIJNEVELD SIJMEN A. , CRONE MATHILDE R. , SCHULLER ANNEMARIE A. , VERHULST FRANK C. , VERLOOVE-VANHORICK S. PAULINE
Published: February 2005

Background. Disasters are believed to have large effects on the mental health of adolescents but the lack of prospective pre- and post-disaster data on affected and control populations have limited our knowledge on the validity of these claims. We examined the medium-term, 12 months' effects of a severe disaster on the mental health of adolescents, and compared them to effects after 5 months.

Method. A café fire in The Netherlands injured 250 adolescents and killed 14. We obtained data 15 months before and 12 months after the disaster about behavioural and emotional problems (using the Youth Self-Report) and substance misuse, in 124 students of an affected school of whom 31 were present at the fire (response 77·5%) and 830 other students (56·4%); mean age at baseline, 13·8 years.

Results. We found differences between students from the affected school and others for excessive use of alcohol (odds ratio 3·42, 95% confidence interval 2·00–5·85, p<0·0001), but not for behavioural and emotional problems and use of other substances. Effects had decreased compared to those after 5 months.

Conclusions. In the long run, the effects of disaster decrease regarding self-reported behavioural and emotional problems, but they remain regarding alcohol misuse among those present at the disaster, and their peers.
Psychopathology in the adolescent and young adult offspring of a community sample of mothers and fathers with major depression
Authors: KLEIN DANIEL N. , LEWINSOHN PETER M. , ROHDE PAUL , SEELEY JOHN R. , OLINO THOMAS M.
Published: February 2005

Background. There is a large literature indicating that the offspring of mothers with Major Depressive Disorder (MDD) are at increased risk for depression. However, much less is known about the effects of paternal MDD on offspring psychopathology.

Method. We addressed this issue using a large community sample of parents and their adolescent and young adult offspring (n=775). Parents and offspring were independently assessed with semi-structured diagnostic interviews. Offspring were interviewed three times from mid-adolescence to age 24 years.

Results. Maternal MDD was significantly associated with offspring MDD. Paternal MDD was also significantly associated with MDD in offspring, but only among offspring with depressive episodes of moderate or greater severity. These effects persisted after controlling for socio-economic status, family intactness, and non-mood disorders in both parents. Rates of MDD were particularly elevated in offspring of mothers and fathers with early-onset MDD, and offspring of fathers with recurrent MDD. The magnitude of the associations between MDD in parents and offspring was generally in the small-to-medium range.

Conclusions. These results confirm previous findings of elevated risk of MDD in the offspring of depressed mothers. In addition, the results suggest that MDD in fathers is associated with increased risk of depression in offspring, but that it is limited to MDD episodes in offspring of moderate or greater severity.
Is benzodiazepine use a risk factor for cognitive decline and dementia? A literature review of epidemiological studies
Authors: VERDOUX HELENE , LAGNAOUI RAJAA , BEGAUD BERNARD
Published: February 2005

Background. A major public health issue is to determine whether long-term benzodiazepine use may induce cognitive deficits persisting after withdrawal. The aim of the present review was to examine findings from prospective studies carried out in general population samples exploring whether exposure to benzodiazepines is associated with an increased risk of incident cognitive decline.

Method. Using a MEDLINE search and a hand-search of related references in selected papers, we retrieved original studies published in peer-reviewed journals that explored in general population samples the association between benzodiazepine exposure and change in cognitive performance between baseline and follow-up assessment.

Results. Six papers met the inclusion criteria. Two studies reported a lower risk of cognitive decline in former or ever users, two found no association whatever the category of user, and three found an increased risk of cognitive decline in benzodiazepine users.

Conclusions. The discrepant findings obtained by studies examining the link between benzodiazepine exposure and risk of cognitive decline may be due to methodological differences, especially regarding the definitions of exposure and cognitive outcome. As a large proportion of subjects are exposed to benzodiazepines, a small increase in the risk of cognitive decline may have marked deleterious consequences for the health of the general population. This issue needs to be explored further by pharmaco-epidemiological studies.
Dust transport and deposition observed from the Terra‐Moderate Resolution Imaging Spectroradiometer (MODIS) spacecraft over the Atlantic Ocean
Authors: Kaufman Y. J. , Koren I. , Remer L. A. , Tanré D. , Ginoux P. , Fan S.
Published: February 2005

Meteorological observations, in situ data, and satellite images of dust episodes were used already in the 1970s to estimate that 100 Tg of dust are transported from Africa over the Atlantic Ocean every year between June and August and are deposited in the Atlantic Ocean and the Americas. Desert dust is a main source of nutrients to oceanic biota and the Amazon forest, but it deteriorates air quality, as shown for Florida. Dust affects the Earth radiation budget, thus participating in climate change and feedback mechanisms. There is an urgent need for new tools for quantitative evaluation of the dust distribution, transport, and deposition. The Terra spacecraft, launched at the dawn of the last millennium, provides the first systematic well‐calibrated multispectral measurements from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument for daily global analysis of aerosol. MODIS data are used here to distinguish dust from smoke and maritime aerosols and to evaluate the African dust column concentration, transport, and deposition. We found that 240 ± 80 Tg of dust are transported annually from Africa to the Atlantic Ocean, 140 ± 40 Tg are deposited in the Atlantic Ocean, 50 Tg fertilize the Amazon Basin (four times as previous estimates, thus explaining a paradox regarding the source of nutrition to the Amazon forest), 50 Tg reach the Caribbean, and 20 Tg return to Africa and Europe. The results are compared favorably with dust transport models for maximum particle diameter between 6 and 12 μm. This study is a first example of quantitative use of MODIS aerosol for a geophysical research.
The signature of mid‐latitude convection observed by VHF wind‐profiling radar
Authors: Hooper D. A. , McDonald A. J. , Pavelin E. , Carey‐Smith T. K. , Pascoe C. L.
Published: February 2005

The signature of mid‐latitude convection observed by a 46.5 MHz wind‐profiling radar at Aberystwyth, UK (52.4°N, 4.0°W), is demonstrated by way of a case study. A key feature of such radars is their ability to measure the vertical air velocity directly, even under conditions of precipitation. Higher frequency radars, which have more typically been used for such studies, measure the net effect of hydrometeor terminal velocities and the air motion under such conditions. The radar is capable of observing both updrafts and downdrafts, with peak updrafts of the order of 10 m s−1. The signature of convection additionally consists of enhanced values of the radar return spectral width, which cannot be interpreted in terms of turbulence intensity, and reduced reliability of the corresponding radar‐derived horizontal wind components. When convection reaches the uppermost troposphere, the radar return signal power can be anomalously large leading to the radar‐derived tropopause altitude being overestimated. The presence of convection is confirmed by thermal infrared satellite imagery of high‐topped clouds. Use is also made of radiosonde and UHF wind‐profiler data.
The first Mars thermospheric general circulation model: The Martian atmosphere from the ground to 240 km
Authors: Angelats i Coll M. , Forget F. , López‐Valverde M. A. , González‐Galindo F.
Published: February 2005

The Martian general circulation model (GCM) at the Laboratoire de Météorologie Dynamique (LMD) has been extended up to approximately 240 km and it is now the first GCM to fully simulate the Martian atmosphere from the ground up to the thermosphere. In this paper we summarize the processes that have been added and give a first simple study of the effects of parameterized orographic gravity waves on the zonal mean fields. This first study clearly emphasizes the coupling between the different atmospheric regions and notes the importance of having fully coupled models to simulate the atmosphere of Mars.
Active thrust faulting offshore Boumerdes, Algeria, and its relations to the 2003 Mw 6.9 earthquake
Authors: Déverchère J. , Yelles K. , Domzig A. , Mercier de Lépinay B. , Bouillin J.‐P. , Gaullier V. , Bracène R. , Calais E. , Savoye B. , Kherroubi A. , Le Roy P. , Pauc H. , Dan G.
Published: February 2005

We investigate the active seismogenic fault system in the area of the 2003 Mw 6.9 Boumerdes earthquake, Algeria, from a high‐resolution swath bathymetry and seismic survey. A series of 5 main fault‐propagation folds ∼20–35 km long leave prominent cumulative escarpments on the steep slope and in the deep basin. Fault activity creates Plio‐Quaternary growth strata within uplifted areas such as a rollover basin on the slope and piggyback basins in the deep ocean. Most thrusts turn to fault‐propagation folds at the sub‐surface and depict ramp‐flat trajectories. We find that the two main slip patches of the 2003 Mw 6.9 Boumerdes earthquake are spatially correlated to two segmented cumulative scarps recognized on the slope and at the foot of the margin. The overall geometry indicates the predominance of back thrusts implying underthrusting of the Neogene oceanic crust.
Evidence for static stress changes triggering the 1999 eruption of Cerro Negro Volcano, Nicaragua and regional aftershock sequences
Authors: Díez M. , La Femina P. C. , Connor C. B. , Strauch W. , Tenorio V.
Published: February 2005

Remarkable evidence of coupling between tectonic and magmatic events emerges from investigation of three tectonic earthquakes, aftershock sequences and eruption of Cerro Negro volcano, Nicaragua in 1999. Here, we explain this coupling through static stress changes following three Mw 5.2 earthquakes. We use focal mechanism solutions to estimate fault system geometry and magnitude of slip from these events, which are then used to calculate the change in minimum horizontal principal stress (σ3) for the region and the change in Coulomb failure stress on optimally oriented fault planes. Results of these simulations indicate that σ3was reduced by ∼0.08 MPa and that Coulomb failure stress was raised by 0.001 to 0.2 MPa in the region. A Kolmogorov‐Smirnov test demonstrates spatial correlation of Coulomb failure stress changes and triggered seismicity and volcanism, and suggests that these small changes in static stress can trigger subsequent geophysical events under appropriate circumstances.
Interference of extratropical surface climate anomalies induced by El Niño and stratospheric sudden warmings
Authors: Taguchi Masakazu , Hartmann Dennis L.
Published: February 2005

The El Niño/Southern Oscillation (ENSO) and stratospheric sudden warmings (SSWs) each induce significant surface climate anomalies in Northern latitudes during winter. Nonetheless, possible connections between the impacts of the ENSO and SSWs remain relatively unexplored. Using both observational analysis and global climate model (GCM) experiments, we show that the impacts of El Niño and SSWs interfere over North America. The interference includes constructive interference, or synergistic impacts of the El Niño and SSWs over the southeastern US through northern Mexico, resulting in enhancement of colder and wetter climate when El Niño and SSWs occur in the same winter. The interference is of practical importance such as in extended‐range weather forecasts, since the impacts of the two phenomena affect seasonal averages and increase the probability of extreme weather conditions in the region.
Controls on conduit magma flow dynamics during lava dome building eruptions
Authors: Melnik O. , Sparks R. S. J.
Published: February 2005

Lava dome eruptions commonly display fairly regular alternations between periods of high and low or no activity with timescales typically of weeks to years and sudden transitions between effusive and explosive activity. We develop a transient model of the magma flow in a volcanic conduit from an open‐system magma chamber with continuous replenishment. The model incorporates gas exsolution, bubble growth, gas escape through the magma, and decompression‐induced crystallization and considers variations in magma temperature, water content, conduit diameter, phenocryst size, chamber volume, and magma rheology. Calculations show the presence of periodic variations in discharge rate due to the transition from a stable regime, when discharge rate is low and crystals grow efficiently leading to high magma viscosity, to another stable state, when discharge rate is high and crystallization is negligible. The difference in discharge rates between these regimes can be several orders of magnitude. Periods are similar to the observed timescales and mainly depend on the chamber volume. The system shows strongly nonlinear responses to the variation of governing parameters. If magma has a Bingham rheology pauses in discharge rate occur between peaks of discharge and the peaks are much higher than for the case of Newtonian rheology. Large changes in discharge rate and eruptive behavior can occur as the consequence of small changes in magma temperature, water content, phenocryst size distribution, or conduit diameter. The system can fluctuate between low and high discharge rates with transitions to explosive activity.
Stochastic inversion of electrical resistivity changes using a Markov Chain Monte Carlo approach
Authors: Ramirez A. L. , Nitao J. J. , Hanley W. G. , Aines R. , Glaser R. E. , Sengupta S. K. , Dyer K. M. , Hickling T. L. , Daily W. D.
Published: February 2005

We describe a stochastic inversion method for mapping subsurface regions where the electrical resistivity is changing. The technique combines prior information, electrical resistance data, and forward models to produce subsurface resistivity models that are most consistent with all available data. Bayesian inference and a Metropolis simulation algorithm form the basis for this approach. Attractive features include its ability (1) to provide quantitative measures of the uncertainty of a generated estimate and (2) to allow alternative model estimates to be identified, compared, and ranked. Methods that monitor convergence and summarize important trends of the posterior distribution are introduced. Results from a physical model test and a field experiment were used to assess performance. The presented stochastic inversions provide useful estimates of the most probable location, shape, and volume of the changing region and the most likely resistivity change. The proposed method is computationally expensive, requiring the use of extensive computational resources to make its application practical.