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Identifying characteristics of individuals at greatest risk for prolonged grief disorder (PGD) can improve its detection and elucidate the etiology of the disorder. The Safe Passage Study, a study of women at high risk for sudden infant death syndrome (SIDS), prospectively examined the psychosocial functioning of women while monitoring their healthy pregnancies. Mothers whose infants died of SIDS were followed in bereavement.
Pre-loss data were collected from 12 000 pregnant mothers and analyzed for their associations with grief symptoms and PGD in 50 mothers whose infants died from SIDS, from 2 to 48 months after their infant's death, focusing on pre-loss risk factors of anxiety, depression, alcohol use, maternal age, the presence of other living children in the home, and previous child loss.
The presence of any four risk factors significantly predicted PGD for 24 months post-loss (p < 0.003); 2–3 risk factors predicted PGD for 12 months (p = 0.02). PGD rates increased in the second post-loss year, converging in all groups to approximately 40% by 3 years. Pre-loss depressive symptoms were significantly associated with PGD. Higher alcohol intake and older maternal age were consistently positively associated with PGD. Predicted risk scores showed good discrimination between PGD and no PGD 6–24 months after loss (C-statistic = 0.83).
A combination of personal risk factors predicted PGD in 2 years of bereavement. There is a convergence of risk groups to high rates at 2–3 years, marked by increased PGD rates in mothers at low risk. The risk factors showed different effects on PGD.
Studies in the use of the purine derivatives technique in ruminants have been stimulated by the possible use of this technique as an estimator of the rumen microbial-N supplied to the host animal. The recovery factor influences the estimation of the total purines absorbed and therefore the microbial-N supply. The relationship between exogenous purine input and urinary excretion and recovery has been studied using cattle maintained with the intragastric infusion technique (Orskov et al., 1979). The urinary recovery of exogenous purines has been estimated to be 0.77-0.85 (Chen et al., 1990a, Verbic et al., 1990), and this relationship has been assumed to be applicable to normal feeding situations. To our knowledge there is no data to support or reject this approach. This study examined the urinary recovery of exogenous allantoin input in steers under normal feeding conditions.
N-alkanes are components of plant cuticular wax which have been successfully used as markers for the estimation of grass intake and digestibility in grazing ruminants (Dove and Mayes, 1991). Natural n-alkanes are predominately odd chain, and a known dose of an artificial even chain n-alkane (normally c32 or c36) is used to enable intake to be measured. Dietary n-alkanes may behave differently in the gastro-intestinal tract of ruminants and non-ruminants (Mayes et al, 1995). Therefore, in order to utilise this methodology in studies of outdoor pigs, this experiment was carried out to validate the faecal recovery of n-alkanes in this species. Since n-alkanes are soluble in lipid, which is often incorporated at high inclusion levels in pig diets, the experiment was also designed to determine whether n-alkane recovery is influenced by dietary lipid content.
Shallow ice cores were obtained from widely distributed sites across the West Antarctic ice sheet, as part of the United States portion of the International Trans-Antarctic Scientific Expedition (US ITASE) program. The US ITASE cores have been dated by annual-layer counting, primarily through the identification of summer peaks in non-sea-salt sulfate (nssSO42–) concentration. Absolute dating accuracy of better than 2 years and relative dating accuracy better than 1 year is demonstrated by the identification of multiple volcanic marker horizons in each of the cores, Tambora, Indonesia (1815), being the most prominent. Independent validation is provided by the tracing of isochronal layers from site to site using high-frequency ice-penetrating radar observations, and by the timing of mid-winter warming events in stable-isotope ratios, which demonstrate significantly better than 1 year accuracy in the last 20 years. Dating precision to ±1 month is demonstrated by the occurrence of summer nitrate peaks and stable-isotope ratios in phase with nssSO42–, and winter-time sea-salt peaks out of phase, with phase variation of <1 month. Dating precision and accuracy are uniform with depth, for at least the last 100 years.
We describe a hybrid pixel array detector (electron microscope pixel array detector, or EMPAD) adapted for use in electron microscope applications, especially as a universal detector for scanning transmission electron microscopy. The 128×128 pixel detector consists of a 500 µm thick silicon diode array bump-bonded pixel-by-pixel to an application-specific integrated circuit. The in-pixel circuitry provides a 1,000,000:1 dynamic range within a single frame, allowing the direct electron beam to be imaged while still maintaining single electron sensitivity. A 1.1 kHz framing rate enables rapid data collection and minimizes sample drift distortions while scanning. By capturing the entire unsaturated diffraction pattern in scanning mode, one can simultaneously capture bright field, dark field, and phase contrast information, as well as being able to analyze the full scattering distribution, allowing true center of mass imaging. The scattering is recorded on an absolute scale, so that information such as local sample thickness can be directly determined. This paper describes the detector architecture, data acquisition system, and preliminary results from experiments with 80–200 keV electron beams.
The spectral classifications of the stars from spectral data have been corrected from time to time and new spectral and luminosity classes have been assigned. Identifying stars with wrong spectral and luminosity classification has been a stupendous task from the huge catalogue of stars. In this work we describe a simple statistical technique to identify stars with wrong spectral and luminosity classification. We make use of the Hipparcos catalogue which has the most accurate measurement of the distance d of the stars. A comparison is made between the absolute V magnitudes MV computed using the observed V magnitude mV and d, with the standard absolute magnitude MV0 assigned to a spectral and luminosity classification for a large number of stars (with d < 100 pc). As expected, for most of the stars the difference between MV and MV0 lies within the range ±2 mag, due to the intrinsic nature of each star ignored in this generalisation. A systematic error analysis is made of all the observable used in the computation. Therefore to identify stars which we suspect to be wrongly classified, we look for abnormal deviation in |MV – MV0| ≥5. The location of these stars with respect to the galactic plain and interstellar extinction is also investigated to rule out effects due to variations in the interstellar extinction. From our results we see that some of the stars were indeed wrongly classified and have recently been reclassified (SIMBAD). The reclassification drastically reduces the |MV – MV0| deviation. The other stars in the list which have not yet been reclassified need to be spectroscopically investigated and classified again.
Socio-behavioural factors and pathogens associated with childhood diarrhoea are of global public health concern. Our survey in 696 children aged ⩽2 years in rural West Bengal detected rotavirus as sole pathogen in 8% (17/199) of diarrhoeic stool specimens. Other organisms were detected along with rotavirus in 11% of faecal specimens. A third of the children with rotavirus diarrhoea, according to Vesikari score, had severe illness. The top four rotavirus genotypes were G9P (28%), G1P (19%), G2P (14%) and G8P (8%). In the multivariate model, the practice of ‘drawing drinking water by dipping a pot in the storage vessel’ [adjusted odds ratio (aOR) 2·21, 95% confidence interval (CI) 1·03–4·74, P = 0·041], and ‘children aged ⩽6 months with non-exclusive breastfeeding’ (aOR 2·07, 95% CI 1·1–3·82, P = 0·024) had twice the odds of having diarrhoea. Incidence of rotavirus diarrhoea was 24/100 child-years in children aged >6–18 months, 19/100 child-years in children aged >18–24 months and 5/100 child-years in those aged ⩽6 months. Results have translational implications for future interventions including vaccine development.
Bidirectional reflectance of a surface is defined as the ratio of the scattered radiation at the detector to the incident irradiance as a function of geometry. Accurate knowledge of the bidirectional reflection function for layers composed of discrete, randomly positioned scattering particles is essential for many remote sensing, engineering, and biophysical applications, as well as for different areas of astrophysics. Computations of bidirectional reflection functions for plane parallel particulate layers are usually reduced to solving the radiative transfer equation by the existing techniques. In this work we present our laboratory data on bidirectional reflectance versus phase angle for two sample sizes of alumina, 0.3 and 1 μm, for the He–Ne laser at wavelengths of 632.8 nm (red) and 543.5 nm (green). The nature of the phase curves of the asteroids depends on the parameters like particle size, composition, porosity, roughness, etc. In the present study we analyze data which are being generated using a single scattering phase function, that is, Mie theory of treating particles as a compact sphere. The well-known Hapke formula, along with different particle phase functions such as Mie and Henyey–Greenstein, will be used to model the laboratory data obtained at the asteroid laboratory of Assam University.
Nanoscale heterojunction systems consisting of fullerenes blended with conjugated polymers are promising materials candidates for achieving high performance organic photovoltaic (OPV) devices. In order to understand the phase behaviour in these thin film devices, we have used neutron reflectivity to determine the behavior of model conjugated polymer-fullerene mixtures. Neutron reflectivity is particularly useful for these types of thin film studies since the fullerenes generally have a higher scattering contrast with respect to most polymers. We are studying model bulk heterojunction (BHJ) films based on mixtures of poly(3-hexyl thiophene)s (P3HT), a widely used photoconductive polymer, and different fullerenes (C60, PCBM and bis-PCBM). We have used neutron reflection measurements to determine the film morphology normal to the film surfaces in real device configurations. The novelty of the approach over previous studies is that the BHJ layer is measured with the confining films of PEDOT/PSS and Al in place. Using this model system, we have measured the effect of typical thermal annealing processes on the film development as a function of the polythiophene-fullerene mixtures.
The electronic structure of Co (100 Å)/Cu (50 Å) bilayer film on Si(100) has been investigated using valence band photoemission at 50 eV. The aim is to understand the Co/Cu interface and the nature of intermixing in Co and Cu layers. The valence band of Co/Cu interface shows three features at −0.3, −1.17 and −1.9 eV binding energy. The experimental observations are explained with the help of calculations based on projected augmented wave pseudopotential method using density functional theory. The origin of −0.3 eV feature is mainly due to the Co 3d minority spin states while the features at −1.17 and −1.9 eV are due to the formation of Co and Co–Cu mixed nanoclusters at the interface.
The electronic structure of CeAg2Ge2 single crystal has been investigated by using resonant valence band photoemission and angle-resolved photoemission spectroscopy at different photon energies. Resonant photoemission has been observed near the 4d threshold of Ce at 121 eV. The constant initial state spectra show two photoemission features having 4f character near the Fermi level that exhibits Fano-like sharp resonance profile. Experimental energy bands have been mapped from the normal-emission photoelectron spectra of CeAg2Ge2 (001) surface along the Γ–Z direction. Four photoemission features are observed to show the dispersion related to the Ce 4f states and the hybridized Ag 4d with Ge 4p states. The experimental spectra have been interpreted with the help of calculations based on full potential linear augmented plane wave method using density functional theory.
We have studied wet-chemical and dry etching properties of doped and undoped hydrogenated amorphous silicon (a-Si:H) films with bonded hydrogen content varying from 0 to 20 at.%. Etching processes studied include (1) wet-chemical etching using solutions of KOH, isopropyl alcohol (IPA), and H2O, (2) hydrogen plasma etching, and (3) XeF2 vapor etching.
We study resonant tunneling through a layered medium with a passive negative index medium (NIM) slab as a constituent layer. Using a causal
model for susceptibilities with the parameters of a recently reported metamaterial [G. Dolling, C. Enkrich, M. Wegener, C.M. Soukoulis, S. Linden, Opt. Lett. 31, 1800 (2006)] we show that resonant tunnelling and the associated delay are mostly suppressed. This is in sharp contrast with the naive approach of retaining phase velocity dispersion with arbitrary low losses, predicting sharp resonances with large associated delays. This is shown to be a nontrivial issue because of the necessity of losses for NIM behaviour, while their presence spoils the quality factor of the resonant devices.
Cystic echinococcosis (CE) caused by the larval stage of Echinococcus granulosus is a disease that affects both humans and animals. In humans the disease is treated by surgery with a supplementary option of chemotherapy with a benzimidazole compound. During the present study heat-shock protein 60 (HSP 60) was identified as one of the most frequently expressed biomolecules by E. granulosus after albendazole treatment. Data were correlated with 14-3-3 protein signature, and overexpression of this molecule after albendazole induction was an indicator of cell survival and signal transduction during in vitro maintenance of E. granulosus for up to 72 h. This observation was further correlated with a uniform expression pattern of a housekeeping gene (actin II). Out of three β-tubulin gene isoforms of E. granulosus, β-tubulin gene isoform 2 showed a conserved point mutation indicative of benzimidazole resistance.
Over a 2-year period, 25 families comprising of 181 individuals of all ages were longitudinally observed for the excretion of Campylobacter species. Faecal samples were taken from all persons with diarrhoea. Specimens were also taken from apparently healthy individuals and from domestic animals living within the confines of the study families at monthly intervals.
The overall diarrhoea attack rate was 19 episodes per 100 person-years with peak incidence in the 1- to 4-year-old age group (76/100 person-years). Eight (11·5%) of the total episodes were campylobacter-associated and the overall rate of campylobacter positive diarrhoeal episodes were 2·2 per 100 person-years. Of the 1002 stool samples from healthy individuals 32 (3·2/100 samples) were positive for campylobacter. The organism was most frequently isolated from children under 1 year of age both during diarrhoeal episodes (11·5 per 100 person-years) and non-diarrhoeal (11·1 per 100 samples). Multiple infections in a family were rare. In 19·4% of the occasions one or more animals were campylobacter positive. However, only in 7·7% of these occasions was a human infection recorded within 1 month after the animal was found to be positive.
The study showed that the epidemiology of campylobacteriosis in this community was distinct compared to that observed in developed countries.
Farmers have become heavily reliant on anthelmintics for the control of nematode parasites Due to the widespread development of anthelmintic resistance, alternative approaches for control of nematode parasites are needed. Cruden and Hovell (2008) reported that commercial lambs treated with quebracho tannin had reduced faecal egg counts and improved lamb growth. This paper reports a second in vivo study with quebracho tannins at higher dose rates in lambs.
The first of several cases of meningococcal meningitis was reported in April 2005, in New Delhi, India. Subsequent to this the Government declared an outbreak, which persisted for two periods, from April–July 2005 and January–March 2006. The National Institute of Communicable Diseases (NICD) recommended using WHO criteria for diagnosis of disease. During the outbreak 380 clinically suspected cases were investigated. Of 55 cases diagnosed as confirmed/probable the mortality rate was 14·6%. Meningitis was reported in 60% of cases and meningococcaemia in 40%. Microscopy of petechial rash was positive in 87·5%, CSF Gram stain positive in 68·3%, and latex agglutination test of CSF positive in 64·9% of samples. Neisseria meningitidis (serogroup A) was isolated from 37·7% of cases, 57·7% from CSF. Blood culture was positive in 10·4% of cases. CrgA polymerase chain reaction for N. meningitidis confirmed the isolates. All isolates were susceptible to third-generation cephalosporins, azithromycin and rifampicin, with increasing resistance to ceftriaxone. Penicillin resistance was encountered in 15·4% of strains. Resistance to quinolones was very high at 100% for levofloxacin, 84·6% for ofloxacin and 65·4% for ciprofloxacin. All patients with penicillin-resistant organisms (4) or intermediate sensitivity (4) succumbed to the disease. These patients also had a higher minimum inhibitory concentration to ceftriaxone.
Fourteen strains of S. Typhi (n=13) and S. Paratyphi A (n=1) resistant to ciprofloxacin were compared with 30 ciprofloxacin decreased-susceptibility strains on the basis of qnr plasmid analysis, and nucleotide substitutions at gyrA, gyrB, parC and parE. In ciprofloxacin-resistant strains, five S. Typhi and a single S. Paratyphi A showed triple mutations in gyrA (Ser83→Phe, Asp87→Asn, Glu133→Gly) and a novel mutation outside the quinolone resistance determining region (QRDR) (Met52→Leu). Novel mutations were also discovered in an isolate (minimum inhibitory concentration 8 μg/ml) in gyrA gene Asp76→Asn and outside the QRDR Leu44→Ile. Out of 30 isolates with reduced susceptibility, single mutation was found in 12 strains only. Genes encoding qnr plasmid (qnr A, qnr B, AAC1-F) were not detected in ciprofloxacin-resistant or decreased-susceptibility strains. Antimicrobial surveillance coupled with molecular analysis of fluoroquinolone resistance is warranted for reconfirming novel and established molecular patterns of resistance, which is quintessential for reappraisal of enteric fever therapeutics.
The objectives of the present study were to investigate the recovery of [14C]allantoin in urine of sheep dosed intravenously and degradation of allantoin by rumen micro-organisms. The recovery of [14C]allantoin in the urine of eight sheep was measured during three periods in two experiments. Individual values of [14C]allantoin recovery varied from 66 to 95 % (mean value 83 (SE 1·6) %). The recovery of [14C]allantoin showed no relation to the level of feed intake. There was some evidence that glomerular filtration rate was an important factor affecting the amount of urinary allantoin recovered in one experiment. Incomplete recovery of plasma [14C]allantoin in the urine indicated losses of plasma [14C]allantoin via non-renal routes. This is supported by the disappearance of 14C from rumen contents incubated in vitro with [14C]allantoin for 48 h (88 %) and the presence of 14C in saliva in vivo from sheep sampled after dosing with [14C]allantoin. However, the amount of 14C activity in the saliva was very low (equivalent to only 1·5 % of the total dose in sheep producing saliva at a rate of 15 litres/d). The proportion of renal and non-renal excretion of purine derivatives was found to be unpredictable both between and within individual animals. The factors responsible for this variability need to be identified, and existing models of excretion of purine derivatives may need to be modified accordingly to improve their accuracy of prediction. A single intravenous injection of [4,5-14C]allantoin provides a simple alternative to infusion methods used to measure the proportion of plasma allantoin excreted in the urine of sheep. Using this method it may be feasible to validate PD excretion models in other ruminant livestock.
The intake and the digestibility of herbage, and the effect of level of supplementary concentrate food, were measured in late spring and late summer in two studies, each with eight multiparous, pregnant sows. In the spring study sows were nose rung to prevent rooting but only four nose-rung sows were available for the summer study; the remaining four were unrung. In both cases, sows had access to a plentiful (>2·5 t organic matter (OM) per ha) ryegrass/clover sward in a paddock of 1922 m2. After a week of adaptation to the herbage in the experimental paddock, sows were offered 1·5 or 3·0 kg/day concentrate for consecutive 2-week periods in a change-over experimental design with four sows on each treatment in each period. Samples of herbage were also taken to measure the sward density, chemical composition and n-alkane content. Herbage intake and digestibility estimates were calculated using the n-alkanes technique, with the marker dosed on small food pellets. In the spring study, the herbage intake ranged from 0·9 to 1·8 kg OM per day in the first period (herbage neutral-detergent fibre(NDF) content 439 (s.e.41·6) g/kg OM) and 0·2 to 1·4 kg in the second (475 (s.e.29·3) g NDF per kg OM). The intake was affected by the level of concentrate only in the second period. The results obtained during the summer study with the rung and unrung sows showed an intake between 0·9 and 2·4 kg OM per day in the first period (524 (s.e. 16·0) g NDF per kg OM) and between 1·3 and 4·8 kg in the second (526 (s.e. 21·8) g NDF per kg OM). A high intake estimation for certain unrung individuals appeared to reflect their frenzied feeding behaviour and possible loss of some marker pellets. There were no differences between level of concentrate treatments in either period. Digestibility of the diet was affected by the intake of herbage and the level of fibre consumed (P < 0·01). These herbage intakes equated to proportionately 0·50 (s.e. 0·05) and 0·66 (s.e. 0·1) (or 0·49 (s.e. 0·07) excluding problem sows) of the maintenance energy requirement in each season. Faeces of unrung sows indicated a high ingestion of soil or stones by some individuals: one of the sows produced a bulked faeces sample containing 450 g/kg fresh weight of stones, whilst another sow had a faecal ash content of 937 g/kg DM. The results indicate that the intake of nutrients from herbage by grazing sows is highly variable between seasons and individuals.