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The focus of interventions for adults living with HIV (ALH) in Nigeria has been mostly on prevention and provision of antiretroviral therapy (ART) with little consideration to nutrition-related matters. Therefore, the present study aimed to improve the quality of life (QoL) and anthropometric status of ALH in Abeokuta, Nigeria.
A quasi-experimental design where 200 conveniently selected participants were stratified by gender and duration on ART. The intervention group (n 100) received the nutrition education programme (NEP) for 12 weeks. The control group received a brochure on nutrition guidelines for ALH. Socio-biographical information, QoL and anthropometric status were assessed using previously validated questionnaires and standard techniques at baseline, week 12 and week 24. Generalised least squares (GLS) regression analysis was used for group comparisons. Anthropometric status was summarised by gender.
Two tertiary hospitals in Abeokuta, Nigeria.
The NEP led to significant improvement in the physical functioning (week 12 and 24: P < 0·01), role limitation due to physical health (week 12: P = 0·01; week 24: P = 0·002) and pain (week 12: P = 0·01) constructs of the QoL of the intervention group compared with the control group. There was no significant difference (P = 0·07) between the mean weights of the two groups at baseline.
There was a significant improvement at week 12 and week 24 in the QoL of the intervention participants. The results indicated that a tailored NEP could make a positive contribution to the management of ALH.
Pathogen spillover from wildlife to humans or domestic animals requires a series of conditions to align with space and time. Comparing these conditions between times and locations where spillover does and does not occur presents opportunities to understand the factors that shape spillover risk. Bovine rabies transmitted by vampire bats was first confirmed in 1911 and has since been detected across the distribution of vampire bats. However, Uruguay is an exception. Uruguay was free of bovine rabies until 2007, despite high-cattle densities, the presence of vampire bats and a strong surveillance system. To explore why Uruguay was free of bovine rabies until recently, we review the historic literature and reconstruct the conditions that would allow rabies invasion into Uruguay. We used available historical records on the abundance of livestock and wildlife, the vampire bat distribution and occurrence of rabies outbreaks, as well as environmental modifications, to propose four alternative hypotheses to explain rabies virus emergence and spillover: bat movement, viral invasion, surveillance failure and environmental changes. While future statistical modelling efforts will be required to disentangle these hypotheses, we here show how a detailed historical analysis can be used to generate testable predictions for the conditions leading to pathogen spillover.
Unbalanced metabolic status in the weeks after calving predisposes dairy cows to metabolic and infectious diseases. Blood glucose, IGF-I, non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHB) are used as indicators of the metabolic status of cows. This work aims to (1) evaluate the potential of milk mid-IR spectra to predict these blood components individually and (2) to evaluate the possibility of predicting the metabolic status of cows based on the clustering of these blood components. Blood samples were collected from 241 Holstein cows on six experimental farms, at days 14 and 35 after calving. Blood samples were analyzed by reference analysis and metabolic status was defined by k-means clustering (k=3) based on the four blood components. Milk mid-IR analyses were undertaken on different instruments and the spectra were harmonized into a common standardized format. Quantitative models predicting blood components were developed using partial least squares regression and discriminant models aiming to differentiate the metabolic status were developed with partial least squares discriminant analysis. Cross-validations were performed for both quantitative and discriminant models using four subsets randomly constituted. Blood glucose, IGF-I, NEFA and BHB were predicted with respective R2 of calibration of 0.55, 0.69, 0.49 and 0.77, and R2 of cross-validation of 0.44, 0.61, 0.39 and 0.70. Although these models were not able to provide precise quantitative values, they allow for screening of individual milk samples for high or low values. The clustering methodology led to the sharing out of the data set into three groups of cows representing healthy, moderately impacted and imbalanced metabolic status. The discriminant models allow to fairly classify the three groups, with a global percentage of correct classification up to 74%. When discriminating the cows with imbalanced metabolic status from cows with healthy and moderately impacted metabolic status, the models were able to distinguish imbalanced group with a global percentage of correct classification up to 92%. The performances were satisfactory considering the variables are not present in milk, and consequently predicted indirectly. This work showed the potential of milk mid-IR analysis to provide new metabolic status indicators based on individual blood components or a combination of these variables into a global status. Models have been developed within a standardized spectral format, and although robustness should preferably be improved with additional data integrating different geographic regions, diets and breeds, they constitute rapid, cost-effective and large-scale tools for management and breeding of dairy cows.
In vitromethods for laboratory estimation of food degradation are important tools for nutritionists.These methods either measure substrate disappearance by quantifying incubation residues or record fermentation products such as microbial biomass, short-chain fatty acids (SCFA) or gas volume (Blümmel et al., 1997a). Recently, the surge of interest in the efficient utilization of roughage diets has caused an increase in the use of gas methods because of the possibility of estimating the extent and rate of degradation in one sample by time series measurements of the accumulating gas volume. We combined gas measurements with residue determinations (truly degraded substrate) or microbial mass determination after fermentation to study the effects of natural plant products, in particular tannins and saponins, on the availability and partitioning of nutrients.
The separation of forages into a soluble fraction like cell contents and into an insoluble matrix like cell walls is an initial step in forage evaluation. Further analysis can be applied to study fermentation characteristics of soluble and insoluble fractions. Unfortunately, most laboratory in vitro techniques quantify incubation insoluble residues and are therefore inappropriate for the examination of food solubles. In vitro gas methods (for example Menke et al., 1979) reflect the production of short chain fatty acids (SCFA) and are therefore free of the disadvantages associated with gravimetric methods. However, it was recently pointed out that an inverse relationship may exist between SCFA production and microbial biomass yield (for review see Blümmel et al., 1997a). These authors suggested combining in vitro gas measurements with the quantification of substrate concomitantly degraded to calculate a partitioning factor (PF). This factor reflects the substrate-dependent variation in SCFA production and microbial biomass yield; the factor (PF) was shown to be valuable in voluntary food intake (DMI) predictions (Blümmel et al., 1997b). In the work presented here, the rate and extent of fermentation of whole roughages and extracted neutral-detergent fibres (NDF) of 54 roughages were examined in an in vitro gas test. The dry-matter degradability of extracted NDF was also quantified and the partitioning factor for NDF (PFNDF) was determined. The relevance of these findings for the analysis of extracted NDF and cell solubles is discussed and their implications for the prediction of DMI of roughages by gas tests are addressed.
In vitro rumen incubation systems are widely used to determine substrate degradation and the amount of fermentation products like gases, short chain fatty acids and the microbial biomass produced. Here we compare the influence of the amount of inoculum used for preparing the incubation medium on short chain fatty acid production and composition. Treatments were 10% and 30% (v/v) of filtered rumen fluid used for inoculation. In a series of experiments it was demonstrated that the two treatments did not alter the gas production or the amount of substrate truly degraded. However, SCFA production (especially acetate) was significantly reduced when only 10% of inoculum were used for incubation. We propose that acetate was taken up by rumen microorganisms as a precursor for growth, although it cannot be excluded that an altered microbial composition contributed to the observed differences.
Static surface shapes of a magnetic fluid volume between two plates in a non-uniform magnetic field are investigated theoretically and experimentally. Abrupt changes and hysteresis of the magnetic fluid surface shape are observed in the experiments when the current in the coil increases and decreases quasi-statically. The necessary and sufficient conditions for a local minimum of the energy functional are derived theoretically. A method to find stable/unstable surface shapes is developed. The ambiguity in the determination of the magnetic fluid surface shape at the same value of the current is shown. It is found that the experimentally observed surface shapes of the given magnetic fluid volume coincide with the shapes obtained numerically, and practically all of them satisfy the derived necessary and sufficient conditions of the minimum energy. The stability curves of the magnetic fluid bridge between the plates are determined experimentally and theoretically.
UV spectra of CSPN are dominated by lines from ions of iron group elements. Recently we have developed a non-LTE model of the Fe V spectrum putting particular emphasis on this spectral region (Becker and Butler, 1992a). Lines of Ni IV and Ni V are major contributors to blends with the dominating Fe V lines. Meanwhile, non-LTE models for Ni IV, Ni V and Ni VI have been developed (Becker and Butler, 1992b) and the non-LTE model spectra composed of lines from all four ions can be compared to the observations.
Panic disorder (PD) patients are constantly concerned about future panic attacks and exhibit general hypersensitivity to unpredictable threat. We aimed to reveal phasic and sustained brain responses and functional connectivity of the amygdala and the bed nucleus of the stria terminalis (BNST) during threat anticipation in PD.
Using functional magnetic resonance imaging (fMRI), we investigated 17 PD patients and 19 healthy controls (HC) during anticipation of temporally unpredictable aversive and neutral sounds. We used a phasic and sustained analysis model to disentangle temporally dissociable brain activations.
PD patients compared with HC showed phasic amygdala and sustained BNST responses during anticipation of aversive v. neutral stimuli. Furthermore, increased phasic activation was observed in anterior cingulate cortex (ACC), insula and prefrontal cortex (PFC). Insula and PFC also showed sustained activation. Functional connectivity analyses revealed partly distinct phasic and sustained networks.
We demonstrate a role for the BNST during unpredictable threat anticipation in PD and provide first evidence for dissociation between phasic amygdala and sustained BNST activation and their functional connectivity. In line with a hypersensitivity to uncertainty in PD, our results suggest time-dependent involvement of brain regions related to fear and anxiety.
High precision radiocarbon measurements (±2.5‰ STD) were carried out on absolutely dated European oak material. These showed that significant short-term atmospheric 14C variations of up to 2 percent occurred between AD 200 and 800. These changes, reflecting a 150-to 180-year periodicity, seem to correlate with the average sunspot activity around that time. In comparison with results obtained by other authors, a very regular pattern of natural atmospheric 14C variations is exhibited.
This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-BIO, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we present the first preliminary flux limits from AMANDA-II on the search for continuous emission from astrophysical point sources, and report on the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
We describe the search for δ Scuti stars in the MACHO database of bulge fields. Concentrating on a sample of high amplitude δ Scutis, we examine the light curves and pulsation modes. We also discuss their spatial distribution and evolutionary status using mean colors and absolute magnitudes.
Real-time detection of microlensing has moved from proof of concept in 1994 (Udalski et al. 1994a, Alcock et al. 1994) to a steady stream of events this year. Global dissemination of these events by the MACHO and OGLE collaborations has made possible intensive photometric and spectroscopic follow up from widely dispersed sites confirming the microlensing hypothesis (Benetti 1995). Improved photometry and increased temporal resolution from follow up observations greatly increases the possibility of detecting deviations from the standard point-source, point-lens, inertial motion microlensing model. These deviations are crucial in understanding individual lensing systems by breaking the degeneracy between lens mass, position and velocity. We report here on GMAN (Global Microlensing Alert Network), the coordinated follow up of MACHO alerts.
Gravitational microlensing is the most straightforward interpretation of the stellar brightenings that have been observed by our team and other experiments. These data have provided some of the most stringent limits to date on the nature of the Galaxy's dark matter halo. The number of events seen towards the LMC indicate that our Galaxy is not surrounded by a “standard” halo of MACHOs in the mass range of 10–6 to 0.3 solar masses. The observed optical depth towards the Galactic Center is an important constraint on the distribution of mass in the plane of the Galaxy.
We have analyzed a sample of 1150 type ab, and 550 type c RR Lyrae stars found in 24 of 94 bulge fields of the MACHO database. These fields cover a range in Galactocentric distances from 0.3 to 1.6 kpc. In combination with the data on the outer bulge fields of Alard (1997) and Wesselink (1987), here we present the surface density distribution of bulge RR Lyrae between 0.3 and 3 kpc.
The MACHO data base has been used to examine light curves of all red giant stars brighter than Mbol ∼ −2 in a 0.5° × 0.5° area of the LMC bar. Periods, often multiple, have been searched for in all stars found to be variable. Five distinct period-luminosity sequences have been found on the low mass (M ≲ 2.25M⊙) giant branch. Comparison of observed periods, luminosities and period ratios with theoretical models identifies Miras unambiguously as radial fundamental mode pulsators, while semi-regular variables can be pulsating in the 1st, 2nd or 3rd overtone, or even the fundamental. All these variables lie on just 3 of the 5 distinct sequences, and they all appear to be on the AGB.
The fourth sequence contains red giants on the first giant branch (FGB) or at the red end of the core-helium burning loops of intermediate mass stars (M ≳ 2.25M⊙). The light curves of these stars strongly suggest that they are contact binaries, and they make up ∼0.5% of stars within 1 mag. of the FGB tip. Stars on the fifth sequence show semi-regular, eclipse-like light curves. The light curves and periods of these stars suggest that they are in semi-detached binaries, transfering mass to an invisible companion via a stellar wind or Roche lobe overflow. They make up ∼25% of AGB stars. If the existence of these red giant contact and semi-detached binaries is confirmed, then extant theories of binary star evolution will require substantial modification.
The MACHO microlensing experiment's time-sampled photometry database contains blue and red lightcurves for nearly 9 million stars in the central bar region of the Large Magellanic Cloud (LMC). We have identified known LMC Planetary Nebulae (PN) in the database and find one, Jacoby 5, to be variable. We additionally present data on the “parent populations” of LMC PN, and discuss the star formation history of the LMC bar.
Küstner (1921) catalogued K648 in his photographic survey of M15, but it was not recognized as a PN central star until Pease (1928) discovered the nebula, denoted Ps1. As one of very few PN known in globular clusters — it was the only known until Gillet et al. (1989) reported the discovery of a second in M22 and Jacoby et al. (this meeting) announced two new but very faint objects — K648 offers one of the better opportunities to study the post-AGB evolution of extreme Pop. II stars. Previous investigations of the nebula and star (Adams et al. 1984; Peña, Torres-Peimbert, & Ruiz 1992; Heber, Dreizler, & Werner 1993) all concluded that the stellar temperature is slightly less than 40000 K. Heber et al. also concluded the photospheric He and C abundances were 3 × and 5 × higher than solar.