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We describe experiments and simulations to investigate the dynamics of a ball bouncing on a rough vibrating surface. Directly measuring the impulse due to each bounce we find that the frictional interaction with the surface is strongly enhanced near to the side wall. The enhanced dissipation arises as a consequence of the coupling between the collision, rotation and surface friction. This dissipation, which for our experimental conditions was estimated to be up to three times larger than the more obvious inelastic collision, can result in an enhanced probability density near boundaries and particle–particle spatial correlations. Our findings imply that the effective particle collision properties cannot be considered independently of the surface's frictional properties. [ABSTRACT FROM AUTHOR]

Shows that the parameters involved in the acoustic description of porous media can be evaluated from the measurement of specific area. Details on the propagation of sound waves in porous media; Capillarity and specific area; Experiments and results; Discussion of results; Conclusion.

We study the capillary condensation of liquid 4He films inside narrow slit pores with a density functional model and compare the result to the predictions of the Kelvin equation. Our investigation, in the wetting situation, indicates that pores with sizes up to 100 Å are still too small for the macroscopic thermodynamic arguments used to derive the Kelvin equation to be successful. The discrepancy is tentatively attributed to the use of a slab-density model and bulk parameters in the region of very thin films. [ABSTRACT FROM AUTHOR]

Many potential causes for painful diabetic neuropathy have been proposed including actions of cytokines and growth factors. High mobility group protein B1 (HMGB1) is a RAGE agonist, increased in diabetes, that contributes to pain by modulating peripheral inflammatory responses. HMGB1 enhances nociceptive behaviour in naïve animals through an unknown mechanism. We tested the hypothesis that HMGB1 causes pain through direct neuronal activation of RAGE and alteration of nociceptive neuronal responsiveness. HMGB1 and RAGE expression were increased in skin and primary sensory (DRG) neurons of diabetic rats at times when pain behaviour was enhanced. Agonist-evoked TRPV1-mediated calcium responses increased in cultured DRG neurons from diabetic rats and in neurons from naïve rats exposed to high glucose concentrations. HMGB1-mediated increases in TRPV1-evoked calcium responses in DRG neurons were RAGE and PKC-dependent, and this was blocked by co-administration of the growth factor splice variant, VEGF-A165b. Pain behaviour and DRG RAGE expression increases were blocked by VEGF-A165b treatment of diabetic rats in vivo. [ABSTRACT FROM AUTHOR]

This paper presents a proof-of-concept optical detector array sensor system to be used in Unmanned Underwater Vehicle (UUV) navigation. The performance of the developed optical detector array was evaluated for its capability to estimate the position, orientation and forward velocity of UUVs with respect to a light source fixed in underwater. The evaluations were conducted through Monte Carlo simulations and empirical tests under a variety of motion configurations. Monte Carlo simulations also evaluated the system total propagated uncertainty (TPU) by taking into account variations in the water column turbidity, temperature and hardware noise that may degrade the system performance. Empirical tests were conducted to estimate UUV position and velocity during its navigation to a light beacon. Monte Carlo simulation and empirical results support the use of the detector array system for optics based position feedback for UUV positioning applications. [ABSTRACT FROM AUTHOR]

Fecal nutrients and apparent total tract digestibility (ATTD) were predicted using near-infrared spectroscopy (NIRS) of feces collected from the pen floor or the rectum of feedlot cattle in 2 studies, and pen floor samples were assessed for their ability to predict NEg, ADG, and G:F. In study 1, 160 crossbred beef steers in 16 pens (4 pens per treatment) were fed dry-rolled barley or wheat (89% of diet DM) processed at 2 levels. Study 2 utilized 160 crossbred beef steers in 20 pens (5 pens per treatment) that were fed dryrolled barley with 4 levels of barley silage (0%, 4%, 8%, and 12% of diet DM). Both studies fed steers to a target weight of 650 kg. Differences in composition of feces collected from the rectum and the pen floor of a subset of steers (3 to 7) were examined. Fecal pats from the pen floor of each pen were collected throughout the feeding period and composited by pen. Except for DM, which was higher (P < 0.01) in pen floor than rectal fecal samples, there were minimal differences in fecal constituents between collection methods. In study 1, interactions between grain type and processing index (P ≤ 0.05) were observed, with a reduction in DM, OM, and starch and an increase in NDF and ADL concentrations being associated with more extensively processed wheat than barley. As grain was more extensively processed, ATTD of all nutrients increased (P < 0.01). In study 2, fecal ADF and ADL linearly increased (P < 0.01) with increasing silage in the diet, whereas fecal DM and N linearly decreased (P < 0.01). Digestibility of all nutrients except starch linearly decreased (P < 0.01) with increasing silage. Apparent total tract digestibility of GE predicted using NIRS was related to NEg of the diets as estimated by performance for the wheat-fed steers in study 1 (R² = 0.58, P = 0.03) and those fed increasing silage in study 2 (R² = 0.43, P < 0.01). Similarly, observed ADG could be predicted using NIRS for steers fed wheat in study 1 (R² = 0.48, P = 0.05) and silage in study 2 (R² = 0.40, P < 0.01), but G:F could not. Using NIRS of feces collected from multiple cattle off the feedlot pen floor demonstrated potential for predicting growth performance of finishing cattle. However, grain type and stage of maturity of the cattle impacted the predictability of equations. Increasing the sample size and sampling frequency may be necessary to improve predictions. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the nutritional value of barley grain differing in diastatic power (DP; high vs. low; a malt trait) and processing index (PI; 75 vs. 85). One hundred sixty Angus x Hereford crossbred yearling steers (467 ± 38 kg; 144 intact and 16 rumen cannulated) were used in a complete randomized 2 x 2 factorial experiment. Steers were assigned to 16 pens, 8 of which were equipped with the GrowSafe system to measure individual feed intake. Cannulated steers (2 per pen) were randomly assigned to the 8 GrowSafe pens. Diets consisted of high- or low-DP barley grain (80.0% of diet DM) processed to an index of either 75 or 85% (PI-75 and PI-85, respectively). Ruminal pH in cannulated steers was measured over four 5-d periods using indwelling electrodes. Fecal samples were collected every 28 d from the rectum of each steer to assess digestibility using AIA as a marker. No differences (P > 0.10) in rumen pH were observed among cattle as measured by the indwelling pH meters. However, lower (P < 0.05) rumen pH was observed for steers fed low- as opposed to high-DP barley in rumen samples collected just prior to feeding and measured in the laboratory. Intake of DM and OM were not affected (P ≥ 0.24) by DP but were lower (P < 0.01) with more severe processing (PI-75 vs. PI-85). Low-DP barley tended to exhibit higher (P = 0.09) total tract DM digestibility than high- DP barley. Steers fed PI-75 barley also had higher (P = 0.06) G:F and NEg. Digestibility of DM, OM, CP, NDF, and starch was higher (P < 0.05) for PI-75 barley than for PI-85 barley. Low-DP barley increased (P < 0.05) carcass dressing percentage by 0.5% compared with high-DP barley, with a lower PI tending to increase (P = 0.06) rib eye area. Compared with steers fed high- DP diets, steers fed low-DP diets had more (P = 0.01) total (41.7 vs. 19.4%) and severe liver abscesses (22.2 vs. 9.7%). Results suggest that although low-DP barley increased liver abscesses, differences in DP did not alter digestion or growth performance but low-DP barley did improve dressing percentage. Barley with different DP responded similarly to processing, with more intensive processing (PI-75) of barley improving starch digestion, feed efficiency, and NEg without negatively affecting rumen pH. [ABSTRACT FROM AUTHOR]

Some species of actinomycetes, fungi, and blue-green algae produce semivolatile off-flavor compounds responsible for earthy-musty odorants in water from aquaculture facilities and tend to bioaccumulate within fish flesh. Although these off-flavor compounds are harmless to human health, high levels within fish tissue lead to an undesirable taste leading to an unmarketable consumption quality. Preharvest processes such as depuration can be used to eliminate most of these off-flavor compounds and ultimately enhance salmon quality. This study examined the potential of near infrared spectroscopy (NIRS) to discriminate depurated from nondepurated salmon fillets ( n = 62). Partial least squares discriminant analysis based on NIR spectra correctly classified 100 % of non-depurated and depurated salmon fillets. The successful classification was likely a consequence of statistically significant differences in the content of off-flavor compounds between both samples, which could have been detected by NIR spectra. Thus, NIRS is a fast, inexpensive, solvent-free, and non-destructive technology that can be used for the authentication of salmon with enhanced quality for marketing purposes. [ABSTRACT FROM AUTHOR]

Our objective was to develop a model to predict the acidosis potential of barley based on the in vitro batch culture incubation of 50 samples varying in bulk density, starch content, processing method, growing location, and agronomic practices. The model was an adaptation of the acidosis index (calculated from a combination of in situ and in vitro analyses and from several components of grain chemical composition) developed in Australia for use in the feed industry to estimate the potential for grains to increase the risk of ruminal acidosis. Of the independent variables considered, DM disappearance at 6 h of incubation (DMD6) using reduced-strength (20%) buffer in the batch culture accounted for 90.5% of the variation in the acidosis index with a root mean square error (RMSE) of 4.46%. To evaluate our model using independent datasets (derived from previous batch culture studies using full-strength [100%] buffer), we performed another batch culture study using full-strength buffer. The full-strength buffer model using in vitro DMD6 (DMD6-FS) accounted for 66.5% of the variation in the acidosis index with an RMSE of 8.30%. When the new full-strength buffer model was applied to 3 independent datasets to predict acidosis, it accounted for 20.1, 28.5, and 30.2% of the variation in the calculated acidosis index. Significant (P < 0.001) mean bias was evident in 2 of the datasets, for which the DMD6 model underpredicted the acidosis index by 46.9 and 5.73%. Ranking of samples from the most diverse independent dataset using the DMD6-FS model and the Black (2008) model (calculated using in situ starch degradation) indicated the relationship between the rankings using Spearman's rank correlation was negative (ρ = -0.30; P = 0.059). When the reduced-strength buffer model was used, however, there were similarities in the acidosis index ranking of barley samples by the models as shown by the result of a correlation analysis between calculated (using the Australian model) and predicted (using the reduced-strength buffer DMD6 model) acidosis index (ρ = 0.67; P < 0.001). Results suggest that our model, which is based on a reduced-strength buffer in vitro DMD6, has the potential to predict acidosis risk and can rank barley samples based on their acidotic risk. Nonetheless, the model would benefit from further refinement by expanding the database. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate the dynamics of submersible mussel rafts, the finite element program Aqua-FE™, developed by the University of New Hampshire (UNH), was applied to rafts moored at the surface and submerged. The submerged configuration is used to reduce wave forcing and to avoid contact with floating ice during winters in northern waters. Each raft consists of three pontoons connected by a grid framework. Rafts are intended to support densely spaced mussel ropes hung from the framework. When submerged, the pontoons are flooded, and the raft is held vertically by floats attached by lines. The computer models were developed in Aqua-FE™ to simulate the effects of waves and current. They were validated by comparison with wave tank results by use of a 1/10 scale raft physical model. Comparisons showed good agreement for the important heave (vertical) and pitch (rotational) motions, though there was a tendency towards conservative results for wave and current drag. Full-scale simulations of surface and submerged single raft and two rafts connected in tandem were performed. Submerged raft wave response was found to be reduced relative to that at the surface for both the single and two-raft configurations. In particular, the vertical motion of mussel rope connection points was significantly reduced by submergence, resulting in reduced potential for mussel drop-off. For example, the maximum vertical velocities of mussel rope attachment points in the submerged two raft case were 7%-20% of the corresponding velocities when at the surface. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Digestibility of ether extract (EE) or fatty acids (FA) is traditionally measured by chemical analyses for EE or GLC methods for FA combined with marker concentration in diet and digesta or feces. Digestibility of EE or FA may be predicted by marker concentrations and spectral analyses of diet and digesta or feces. On the basis of Beer's law, a noncalibration spectroscopic method, which used functional group digestibility (FGD) determined with marker concentration and peak intensity of spectra of diets and undigested residues (digesta or feces), was developed to predict the apparent ileal digestibility (AID) of total FA and apparent total tract digestibility (ATTD) of EE. To validate, 4 diets containing 30% flaxseed and field pea coextruded with 4 extruder treatments and a wheat and soybean basal diet with predetermined AID of total FA and ATTD of EE were used. Samples of ingredients, diets, and freeze-dried digesta and feces were scanned on a Fourier transform infrared (FT-IR) instrument with a singlereflection attenuated total reflection (ATR) accessory. The intensity of either the methylene (CH2) antisymmetric stretching peak at 2,923 cm-1 (R² = 0.90, P < 0.01) or the symmetric stretching peak at 2,852 cm-1 (R² = 0.86, P < 0.01) of ingredients, diet, and digesta spectra was related strongly to the concentration of total FA. The AID of total FA of diets measured using GLC was predicted by the spectroscopic method using FGD at 2,923 and 2,852 cm-1 (R² = 0.75, P < 0.01) with a bias of 0.54 (SD = 3.78%) and -1.35 (SD = 3.74%), respectively. The accumulated peak intensity in the region between 1,766 and 1,695 cm-1 of spectra was related to EE concentration in ingredients and diets (R² = 0.61, P = 0.01) and feces (R² = 0.88, P < 0.01). The relation was improved by using second-derivative spectra of the sum of peak intensities at 1,743 and 1,710 cm-1 for ingredients and diets (R² = 0.90, P = 0.01) and at 1,735 and 1,710 cm-1 for feces (R² = 0.92, P < 0.01). The ATTD of EE of test diets determined with proximate analysis was estimated by the FGD of nonderivative spectra with or without baseline (R² = 0.90, P < 0.01) with a bias of 3.15 (SD = 3.14%) and 3.50 (SD = 3.24%), respectively. In conclusion, instead of using GLC methods or predictions based on calibrations, the AID of total FA and ATTD of EE can also be estimated directly from ATR FT-IR spectra, provided the ratio of marker in the diet and undigested residue is known. [ABSTRACT FROM AUTHOR]

A two-dimensional mathematical model was developed to predict the dynamic response of a moored, floating platform mounting a tidal turbine in current and waves. The model calculates heave, pitch, and surge response to collinear waves and current. Waves may be single frequency or a random sea with a specified spectrum. The mooring consists of a fixed anchor, heavy chain (forming a catenary), a lightweight elastic line, and a mooring ball tethered to the platform. The equations of motion and mooring equations are solved using a marching solution approach implemented using MATLAB. The model was applied to a 10.7-m twin-hulled platform used to deploy a 0.86-m shrouded, in-line horizontal axis turbine. Added mass and damping coefficients were obtained empirically using a 1/9 scale physical model in tank experiments. Full-scale tests were used to specify drag coefficients for the turbine and platform. The computer model was then used to calculate full-scale mooring loads, turbine forces, and platform motion in preparation for a full-scale test of the tidal turbine in Muskeget Channel, Massachusetts, which runs north-south between Martha's Vineyard and Nantucket Island. During the field experiments, wave, current, and platform motion were recorded. The field measurements were used to compute response amplitude operators (RAOs), essentially normalized amplitudes or frequency responses for heave, pitch, and surge. The measured RAOs were compared with those calculated using the model. The very good agreement indicates that the model can serve as a useful design tool for larger test and commercial platforms. [ABSTRACT FROM AUTHOR]

The article discusses a study on monthly modelling of Ammonia emissions from Canada's dairy farms in its 12 ecoregions. It mentions that the said chemical compound from livestock manure is expelled from barns, storages and manure land which affects farm operations as well as human health and ecology whenever it is emitted in the atmosphere. It also notes the application of models for estimating the intensity and spatial extent of the emission and its proportionality to the animal census.

The article presents a study regarding the activity of dairy farmers in Canada in 2005 related to the use of nitrogn (N) and especially practices that led to loss of ammonia (NH3). The study examines the ecoregion and differences in terms of farm size in dairy feed and manure nitrogen management. It reveals the significance of ecoregion and farm size differences in representing the nation's dairy farm management.

The article explores the accuracy of density, chicken apparent metabolizable energy (AME) with and without supplemental enzyme, and near infrared reflectance spectroscopy (NIRS) in predicting swine digestible energy (DE) content of barley. It regarded NIRS as the most effective tool in determining swine DE content of barley, noting its link on the chemical characteristics that influence nutrient digestibility. Relationship of density with DE content in grower pigs is mentioned.

Damage-induced G1 checkpoint in mammalian cells involves upregulation of p53, which activates transcription of p21Waf1 (CDKN1A). Inhibition of cyclin-dependent kinase (CDK)2 and CDK4/6 by p21 leads to dephosphorylation and activation of Rb. We now show that ectopic p21 expression in human HT1080 fibrosarcoma cells causes not only dephosphorylation but also depletion of Rb; this effect was p53-independent and susceptible to a proteasome inhibitor. CDK inhibitor p27 (CDKN1B) also caused Rb dephosphorylation and depletion, but another CDK inhibitor p16 (CDKN2A) induced only dephosphorylation but not depletion of Rb. Rb depletion was observed in both HT1080 and HCT116 colon carcinoma cells, where p21 was induced by DNA-damaging agents. Rb depletion after DNA damage did not occur in the absence of p21, and it was reduced when p21 induction was inhibited by p21-targeting short hairpin RNA or by a transdominant inhibitor of p53. These results indicate that p21 both activates Rb through dephosphorylation and inactivates it through degradation, suggesting negative feedback regulation of damage-induced cell-cycle checkpoint arrest.Oncogene (2007) 26, 6954–6958. doi:10.1038/sj.onc.1210516; published online 7 May 2007 [ABSTRACT FROM AUTHOR]

We propose expansion of the standard 'time-out' into a comprehensive 'preparatory pause' encompassing five well-documented perioperative risk avoidance strategies: beta-adrenergic blockade, DVT prophylaxis, preoperative antibiotics, normothermia, and euglycemia. Although all members of the surgical team acknowledge the clear benefit of these five prophylactic strategies, published national compliance even in the target patient population is a disappointingly consistent 50%. We have developed and field-tested a 'preparatory pause' form that we appended to our 'surgical time-out.' By politely challenging our surgical team as to the inclusion of these five risk avoidance strategies in 167 consecutive patients, we increased our compliance to more than 90% for each preventive measure. We have not attempted to quantify the physical and psychological benefit of complication avoidance due to the enhanced activation of these five prophylactic strategies. Using published surgical complication prevalence data, with and without these accepted risk avoidance measures, we estimate the number of complications per 100 patients avoided. Utilizing the Medicare payment schedule for each complication, we approximate the purely financial benefit of the 'preparatory pause' to be $88,640 per 100 patients, or almost $900 per patient. The now standard surgical 'time-out' is designed to avoid the gratifyingly uncommon problem of 'wrong patient,''wrong procedure,' and 'wrong site.' Many surgeons negotiate an entire career without stumbling over these disastrous problems. We propose expansion of the 'time-out' to include five well-documented perioperative risk avoidance strategies that many of us overlook all too often. [ABSTRACT FROM AUTHOR]

When a bed of fluid-immersed fine grains is exposed to vertical vibration a wealth of phenomena may be observed. At low frequencies a horizontal bed geometry is generally unstable and the bed breaks spatial symmetry, acquiring a tilt. At the same time it undergoes asymmetric granular convection. Fine binary mixtures may separate completely into layers or patterns of stripes. The separated regions may exhibit instabilities in which they undergo wave-like motion or exhibit quasi-periodic oscillations. We briefly review these and a number of related behaviours, identifying the physical mechanisms behind each. Finally, we discuss the magneto-vibratory separation of binary mixtures which results from exposing each component to a different effective gravity and describe the influence of a background fluid on this process. [ABSTRACT FROM AUTHOR]

Sophy Hallam (consultant) and Patience Seebohm (independent researcher) discuss what makes an entrepreneur, and Paul Grey, Ross Parker and Mark Swift (all experts by experience in mental health and enterprise) share their views on what it takes to set up and run your own business. [ABSTRACT FROM AUTHOR]

Genetic predisposition plays an important role in most common psychiatric disorders. The identification of a specific gene associated with a psychiatric illness can lead to improved management of the gene-associated disorder. Mutations in the wolframin gene are associated with mental illness. Many patients with the Wolfram syndrome (WS), who are homozygous or compound heterozygous for wolframin mutations, have severe psychiatric symptoms. In WS families, close blood relatives, who have a high probability of carrying a single wolframin mutation, had a statistically significant excess, over spouse controls, of psychiatric hospitalizations, attempted and completed suicides, and self-reports of mental illness. Since heterozygous carriers of wolframin mutations are relatively frequent in the population according to the general Hardy–Weinberg principle, such mutations might be responsible for the illnesses of many psychiatric patients. The hypothesis that heterozygous carriers of a wolframin mutation are predisposed to psychiatric illness was tested in subjects from 25 WS families. In all, 11 relatives who had psychiatric hospitalizations could be genotyped through mutation analysis. Eight of these carried the wolframin mutation transmitted in their family, significantly (one-sided P=0.0022) more than the 3.0 expected if there were no association between psychiatric hospitalizations and mutations at this locus. All eight mutation-positive subjects had been hospitalized for a major depression. This confirmation of the association is not influenced by confounders, undetected stratification, or genetic heterogeneity. The relative risk of psychiatric hospitalization for depression was estimated to be 7.1 (95% CI 1.9–26.6) for carriers of a single wolframin mutation compared to noncarriers.Molecular Psychiatry (2005) 10, 799–803. doi:10.1038/sj.mp.4001681; published online 26 April 2005 [ABSTRACT FROM AUTHOR]

A modified gravity-type cage, developed by SADCO Shelf Ltd., was examined using numerical and physical models to determine if the cage and mooring system is suitable for an exposed site south of the Isles of Shoals, NH. The 3000-m³ SADCO Shelf Submersible Fish Cage has angled stays between the upper framework and the ballasted bottom rim (in addition to net) to resist the horizontal shear deformation. The mooring system consists of three legs--each made up of a taut vertical chain and an angled rope, both leading to deadweight anchors. Normalized response amplitudes (response amplitude operators) were found for motion response in heave, surge and pitch, and load response in the anchor and bridle lines, in regular (single frequency) waves. In addition, a stochastic approach was taken to determine the motion and load transfer functions in random waves using a spectrum representative of seas at the selected site. In general, the system motion had a highly damped response, with no resonant peaks within the wave excitation range of 0.05 to 0.45 Hz. The anchor line force response was at all frequencies below 5 kN per meter of wave amplitude. The physical model tests showed consistently more conservative (larger) results compared to those for the numerical model. [ABSTRACT FROM AUTHOR]

Recent work in the area of open ocean aquaculture system dynamics has focused separately upon either the response of fish cages in waves or the steady drag response due to ocean currents. In reality, however, forcing on these open ocean structures is a nonlinear, multidirectional combination of both wave and current profiles. At the University of New Hampshire-operated Open Ocean Aquaculture site, data were collected from a wave measurement buoy and a downward-looking Acoustic Doppler Current Profiler to characterize the surface elevation and water velocity profiles during an extreme northeast storm event. In addition to waves and currents, fish cage motion response in heave, surge, and pitch was inferred from accelerometer measurements during the same storm. The environmental data sets obtained during the peak of the storm were processed, analyzed, and used as input to a dynamic finite-element model. Simulations were performed using three load case scenarios: 1) in both waves and currents; 2) in waves only; and 3) in currents only. Model motion response results in both the time and frequency domain were compared with data obtained in situ. In addition to the motion response tests, the wave and current forcing influencing the mooring line tension response was also investigated. Analysis shows that in this case, the currents do not severely influence the oscillatory motion response, but do cause the cage to tilt, layback, and sink. The wave and current interaction effect did, however, influence the anchor line loads with a portion being attributed to nonlinear effects. [ABSTRACT FROM AUTHOR]

This article examines some medical causes of maternal mortality in detail. In patients who are at high risk because of previous thromboembolism, decisions should be made before pregnancy about thromboprophylaxis. Typical risk factors for thromboembolism are previous venous thromboembolism (VTE), known thrombophilia, family history of VTE obesity and increasing age. These will be identified by those, such as physicians and general practitioners, caring for women outwith pregnancy. These doctors must take obstetric medicine more into consideration.

Active surveillance of symptoms and disability due to musculoskeletal disorders (MSD) in working populations can map individual transitions in symptom intensity or disability level. Using repeat surveys, this study examined if aetiological risk factors for new symptoms or disability, measured by interference with activities, were similar to prognostic risk factors for subsequent outcomes of symptoms and disability. This paper reports on 379 Toronto newspaper workers who completed questionnaires in 1996 and 1997. Questions on pain/discomfort during the last year, episode frequency and duration formed the basis for constructing three mutually exclusive symptom levels: noncases (Level 1); mild cases (Level 2); and more severe or frequent pain cases (Level 3). A similar construction of overall interference levels was based on the frequency with which musculoskeletal pain/discomfort interfered with daily, recreational, social and family activities, or ability to do one's job during the previous 12 months. The last was also examined as work interference alone. Levels of symptoms were cross-tabulated by overall and work interference at the two time points and Markov models of transitions between states were formulated. Results indicate that period prevalence of symptoms and overall interference increased between phases, though only significantly for symptoms (Levels 2 and 3, 65.7-70.7%, p = 0.04), while work interference was unchanged (17.9-17.0%). Equivalent proportions of workers improved as worsened in symptoms (21.1 and 22.4%, respectively), overall interference (16.7 and 17.8%), and work interference (7.4 and 6.6%). The only significant predictor for those without work interference at time one was job tenure, which was protective against work interference (Odds Ratio (OR) 1.06, 95% Confidence Interval (CI) 1.01-1.12). Among those who had more severe/frequent symptoms at time one, lack of improvement over time was predicted by longer job tenure (OR = 0.92 per year, CI: 0.87-0.97), greater psychological demands of work (OR = 0.65 per point, CI: 0.51-0.84) and marginally by greater upper extremity disability score. At time one, women with work interference were more likely to have persistent interference at time two (OR = 7.22, CI: 1.57-33.20). Suggestive findings included opposite effects of social support at work: reduced risk of development of new symptoms but increased risk of persistence at the highest symptom level. [ABSTRACT FROM AUTHOR]

The purpose of this study was to apply a benchmarking methodology to identify the most effective approaches used by long-term care facilities in implementing new computerized resident assessment instrument/minimum data set (RAI/MDS) systems and to develop implementation protocols based on these "best practices." Site visits were conducted with 3 long-term care facilities, selected on the basis of a national search. Facility directors, directors of nursing, information system managers, and frontline staff at each facility were targeted, and questionnaires were developed for each to assess factors viewed as important to successful implementation. A convergence was found in recommended action steps reported across sites to facilitate introduction and implementation of new RAI/MDS software. An example of how benchmarking results were used to develop an implementation plan is provided. Benchmarking provided a useful methodology for identifying best practices to guide implementation planing for adoption of a new computerized RAI/MDS system in the current trial. The benchmarking steps described are replicable and can be used to guide implementation of other new systems in the nursing home setting. [ABSTRACT FROM AUTHOR]

The majority of realistic porous materials are composed of pores of which the shape is variable and the size of the pores normally obeys a distinctive statistical distribution. Although the variation of pore shape is less important, the statistical parameters of pore size distribution can have a considerable effect on the acoustic properties of porous media. This paper discusses the application of a simple model for the prediction of the acoustic properties of porous granular media with some assumed pore geometry and pore size distribution close to log-normal. The model is based on the rational (Padé) approximation approach [K. V. Horoshenkov, K. Attenborough, and S. N. Chandler-Wilde, J. Acoust. Soc. Am. 104, 1198-1209 (1998)] which has been developed for some simple pore geometries. It is shown that the experimentally determined pore size distribution for a representative range of granular materials is often close to log-normal. This assumption enables accurate predictions of the acoustic performance of these materials using the presented model. The water suction method is proposed to determine the parameters of the log-normal distribution, which are the mean pore size, <[lowercase_phi_synonym]>, and its standard deviation, σ. This method is nonacoustic, modelless and well-adapted to acoustic materials and, unlike the BET method [S. Brunauer, P. H. Emmett, and E. Teller, J. Am. Chem. Soc. 60, 309-319 (1938)], is easy to reproduce in any basic acoustic laboratory requiring no expensive parts or chemicals. The proposed Padé approximation is based entirely on four measurable nonacoustic parameters, the porosity, Ω, flow resistivity, Rb, tortuosity, q2 and the standard deviation of the pore size, σ. The method is successfully tested on a representative selection of consolidated and nonconsolidated porous granular materials. © 2001 Acoustical Society of America. [ABSTRACT FROM AUTHOR]

Background: Mutations at the ataxia-telangiectasia locus cause a distinctive autosomal recessive syndrome in homozygotes and predispose heterozygotes to cancer and ischemic heart disease.Objective: To examine mortality rates among persons carrying a mutated ataxia-telangiectasia gene.Design: Retrospective cohort study.Setting: The United States and Canada.Participants: 405 grandparents of patients with ataxia-telangiectasia.Measurements: Ages at death and risk for death (from all causes, cancer, ischemic heart disease, and other causes) among carriers and noncarriers of ataxia-telangiectasia mutations.Results: Compared with noncarriers, carriers of a mutated ataxia-telangiectasia allele had a significantly increased risk for death at 20 through 79 years of age (relative risk, 1.9 [95% CI, 1.3 to 2.8]) (P < 0.001). On average, carriers died 7 to 8 years earlier than noncarriers. Cancer caused most of the excess deaths, and ischemic heart disease caused the remainder. Among carriers, relative risk for death from cancer and ischemic heart disease before 80 years of age was 2.6 (CI, 1.4 to 4.7; P = 0.002) and 2.0 (CI, 1.0 to 4.0; P = 0.062), respectively. Compared with noncarriers, carriers who died of cancer were a mean of 4 years younger (P > 0.2) and carriers who died of ischemic heart disease were a mean of 11 years younger (P = 0.006).Conclusion: Carriers of mutations at the ataxia-telangiectasia locus, who make up 1.4% to 2% of the general population, have a higher mortality rate and an earlier age at death from cancer and ischemic heart disease than noncarriers. [ABSTRACT FROM AUTHOR]

An experimental study on the effect of bending vibration on the acoustic properties of thin porous plates is presented. Poroelastic plates are tested in a large impedance tube in the lower frequency range. It is shown that bending vibration can be excited by the incident sound and detected by measuring the acoustic impedance of a plate. This effect together with the effect of the flow resistivity on the values of the acoustic impedance of the plate are shown. The data from the large and small impedance tubes illustrate how these effects are reduced with the reduced size of the plate. © 2000 Acoustical Society of America. [ABSTRACT FROM AUTHOR]

Seed yield of cowpea (Vigna unguiculata (L.) Walp) were assessed in each of two annual growing seasons over the 4-year period 1973 to 1976 from experimental plots under continuous cultivation on land newly cleared from bush regrowth in Ibadan, S. Nigeria. No fertilizer was applied throughout the experimental period. One set of plots was sprayed weekly with DDT during both growing seasons of each year and one received DDT treatment only in the first growing season of each year. The yield from untreated controls was also monitored. Cowpea seed yields varied considerably from season to season and year to year in untreated plots due to differences in pest incidence and climatic conditions. The cowpea yield with time was faster than in untreated plots and by the seventh season of application DDT application did not significantly enhance cowpea yields. Maize was cultivated without pesticide protection during the first season of 1977 in all plots as an additional indicator of soil fertility before the plots were allowed to return to bush fallow. Crop production was lower in plots previously treated with DDT than in untreated plots, and although soil nutrients were depleted by the continuous cultivation there was no greater depletion in the plots with higher yields. It is suggested that the more rapid decline in fertility of plots with a history of DDT treatment may be associated with pesticide effects on the soil biota. [ABSTRACT FROM AUTHOR]