The structure of the upper atmosphere of mars: In situ accelerometer measurements from mars global surveyor

The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90 degreesE and 90 degreesW, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere.     

Effect of Holding and Packing Conditions on Hemolymph Parameters of Freshwater Prawns,Macrobrachium rosenbergii,during Simulated Waterless Transport

Preliminary market research has identified an unfulfilled market potential for live freshwater prawn, Macrobrachium rosenbergii, in urban areas of the USA and Canada. Truck transport is effective but requires shipment of large numbers of prawns to be economically feasible. Most retail markets are ill‐equipped to hold large quantities for subsequent live sales. Air‐freight of smaller quantities has potential but water weight limits its application. Shipping of live aquatic animals in waterless environments has been reported for some finfish and crustaceans. This project utilized biochemical characteristics of prawn hemolymph as measures of sublethal stress during simulated transport. Six trials were conducted to evaluate the effects of different variables involving preshipment holding conditions, acclimation prior to shipping, and conditions inside the shipping container. Trial 1 compared animals shipped in water with those in a non‐aqueous environment. Trial 2 compared three chilling rates (slow chill, fast chill, and no chill). Trial 3 evaluated different holding protocols including fed versus unfed, reduced pH, increased water hardness, and salinity. Trial 4 evaluated the addition of ammonia scavengers to the transport containers. Trial 5 evaluated the use of carbon dioxide scavengers and an anesthetic, AQUI‐S®. Trial 6 used the best results of Trials 2–5 in a combination of “Best Management Practices” (BMP) over extended time periods. Treatments had either three or four replications using Styrofoam boxes, each packed with six individually tagged prawns. Presoaked wood‐shavings and ice packs were used to keep the boxes moist and cool. The boxes were then sealed in individual oxygenated plastic bags. Trials 1–5 were conducted for 16 h and Trial 6 had separate boxes which were opened at 16, 24, and 32 h. Baseline hemolymph samples were taken prior to packing and from prawn alive at the end of all trials. Hemolymph variables included pH, pO₂, pCO_2, HCO₃, tCO₂, calcium, ammonia, osmolality, glucose, lactate, total protein, magnesium, calcium, and potassium. Percent survival and weight loss were also measured. Results of Trial 1 indicated that compared to transport in water, non‐aqueous environment significantly increased (P≤ 0.05) hemolymph levels of CO₂ and ammonia, and significantly reduced levels of oxygen. In Trial 2, survival in the Slow Chill treatment was significantly higher than in the No Chill treatment, although hemolymph characteristics were not impacted. In Trial 3 prawns held in tanks with added salt (17 ppt) had the highest survival and lowest hemolymph concentration of ammonia and partial pressure of CO₂. The ammonia scavengers in Trial 4 had no significant impact on survival or hemolymph variables. The CO₂ scavengers and anesthetic in Trial 5 had no statistically significant impact on survival. The BMP of Trial 6 consisted of, in the following order, holding in 17 ppt marine salt mix, slow chilling, anesthetic (AQUI‐S) dip, and adding limewater (Ca(OH)₂ + H₂O) to the shipping box as a CO₂ scavenger. In Trial 6, after 32 h of simulated “waterless” transport, prawns in the BMP treatment had significantly higher survival (96%) than prawns in the Control treatment (58%). The BMP prawns also had significantly higher partial pressures of oxygen and lower partial pressures of CO₂ in the hemolymph.     

Potassium homeostasis and membrane transport

Cytosolic K⁺ activity in plant cells is about 80 mM and is maintained during moderate K⁺-deprivation. It decreases to much lower values only in extreme K⁺-deficiency. In contrast, the vacuolar K⁺ concentration responds directly to the K⁺ supply and can fall to very low values in severely K⁺-deprived cells. However, there is good evidence for an upper limit for vacuolar K⁺ concentration which is different in roots and leaves. Understanding of the molecular basis of active and passive K⁺ transport in plants has increased enormously in recent years but the role of individual transporters in uptake has still to be fully resolved, as has their regulation in relation to the maintenance of cytosolic and vacuolar K⁺ concentrations. In particular, the inverse relationship between the rate of K⁺ uptake and internal K⁺ concentration that was established over 25 years ago has still not been credibly explained at the molecular level.     

Identification of toxigenic Pasteurella multocida in atrophic rhinitis of pigs by in vitro characterisation

Toxigenic strains of Pasteurella multocida were readily differentiated from non-toxigenic strains by an agarose overlay method using bovine turbinate cells or bovine lung cells. Cells which were young and densely confluent were best suited to this assay. The incubation period required to distinguish toxigenic strains was dependent on the confluence of the monolayers, which was affected by the seeding rate, cell passage level and growth time prior to overlay. The agarose overlay method correctly identified 11 of 11 reference strains of Pasteurella multocida, and visible cytotoxic changes were present in the monolayers after 48 to 65 h. Outbreaks of the enzootic form of atrophic rhinitis in 2 New South Wales piggeries were associated with the isolation of toxigenic type D strains of P. multocida.     

Modeling the Exchanges of Energy, Water, and Carbon Between Continents and the Atmosphere

Atmospheric general circulation models used for climate simulation and weather forecasting require the fluxes of radiation, heat, water vapor, and momentum across the land-atmosphere interface to be specified. These fluxes are calculated by submodels called land surface parameterizations. Over the last 20 years, these parameterizations have evolved from simple, unrealistic schemes into credible representations of the global soil-vegetation-atmosphere transfer system as advances in plant physiological and hydrological research, advances in satellite data interpretation, and the results of large-scale field experiments have been exploited. Some modern schemes incorporate biogeochemical and ecological knowledge and, when coupled with advanced climate and ocean models, will be capable of modeling the biological and physical responses of the Earth system to global change, for example, increasing atmospheric carbon dioxide.     

Applied information retrieval and multidisciplinary research: new mechanistic hypotheses in Complex Regional Pain Syndrome

Background

Collaborative efforts of physicians and basic scientists are often necessary in the investigation of complex disorders. Difficulties can arise, however, when large amounts of information need to reviewed. Advanced information retrieval can be beneficial in combining and reviewing data obtained from the various scientific fields. In this paper, a team of investigators with varying backgrounds has applied advanced information retrieval methods, in the form of text mining and entity relationship tools, to review the current literature, with the intention to generate new insights into the molecular mechanisms underlying a complex disorder. As an example of such a disorder the Complex Regional Pain Syndrome (CRPS) was chosen. CRPS is a painful and debilitating syndrome with a complex etiology that is still unraveled for a considerable part, resulting in suboptimal diagnosis and treatment.

Results

A text mining based approach combined with a simple network analysis identified Nuclear Factor kappa B (NFκB) as a possible central mediator in both the initiation and progression of CRPS.

Conclusion

The result shows the added value of a multidisciplinary approach combined with information retrieval in hypothesis discovery in biomedical research. The new hypothesis, which was derived in silico, provides a framework for further mechanistic studies into the underlying molecular mechanisms of CRPS and requires evaluation in clinical and epidemiological studies.

     

Production Comparison of Three Genetic Strains of Freshwater Prawn,Macrobrachium rosenbergii,Raised Under Two Pond Management Technologies

Three genetic strains (Texas [cultured], Hawaii [cultured], and Myanmar [wild]) of freshwater prawn, Macrobrachium rosenbergii, were characterized and compared under two pond grow‐out management technologies using a 3 × 2 factorial design. Juvenile prawns (45 d nursed juveniles) from each strain were stocked at individual average weights of 0.4 ± 0.3 g (Texas), 0.3 ± 0.2 g (Hawaii), and 0.3 ± 0.2 g (Myanmar). The low input management technology prawns were stocked at 24,700 /ha with no added substrate. The high input management technology prawns were stocked at 74,100 /ha with the addition of artificial substrate. Each of the six treatment combinations were replicated in three, 0.04 ha earthen ponds (total of 18 ponds). Prawns were fed a sinking pellet (32% protein) once daily at a standardized rate. After 112 d, prawns were harvested, bulk weighed, and counted. Survival of Texas strain (95%) was significantly higher (P ≤ 0.05) than Myanmar strain (77–80%) under both management technologies with survival of Hawaii strain (86–91%) intermediate and not significantly different (P > 0.05) from other strains. Under both management technologies, average weight, total production, and marketable percentage (>20 g) was significantly better (P ≤ 0.05) in Texas and Hawaii strains in comparison to the Myanmar strain. These data appear to indicate that the cultured strains evaluated in this study demonstrate positive impacts of domestication and do not indicate inbreeding depression.     

Current Status of Genetic Studies of Exocrine Pancreatic Insufficiency in Dogs

Exocrine pancreatic insufficiency (EPI) is a disorder wherein the pancreas fails to secrete adequate amounts of digestive enzymes. In dogs, EPI is usually the consequence of an autoimmune disease known as pancreatic acinar atrophy. Originally believed to be a simple autosomal recessive disorder, a test-breeding recently revealed that EPI has a more complex mode of inheritance. The contributions of multiple genes, combined with environmental factors, may explain observed variability in clinical presentation and progression of this disease. Research efforts aim to identify genetic variations underlying EPI to assist breeders in their efforts to eliminate this disease from their breed and provide clinicians with new targets for therapeutic intervention and/or disease prevention. Genome-wide linkage, global gene expression, and candidate gene analyses have failed to identify a major locus or genetic variations in German Shepherd Dogs with EPI. Recently, genome-wide association studies revealed numerous genomic regions associated with EPI. Current studies are focused on alleles of the canine major histocompatibility complex. In this article we review findings from scientific investigations into the inheritance and genetic cause(s) of EPI in the purebred dog.     

Toxoplasma gondii-like organisms in skin aspirates from a cat with disseminated protozoal infection

An 8-year-old, male domestic shorthair cat was referred to the Matthew J. Ryan Veterinary Hospital of the University of Pennsylvania with a 3-day history of lethargy, inappetance, hyperemic skin nodules, coughing, and vomiting. Laboratory results included nonregenerative anemia, lymphopenia, thrombocytopenia, hypoalbuminemia, hyponatremia, and increased alanine aminotransferase and aspartate aminotransferase activities. Cytology of the skin nodules revealed many spindle- to crescent-shaped protozoal organisms, with morphology consistent with Toxoplasma gondii or Neospora caninum. Gross necropsy, histopathologic, immunohistochemical, and transmission electron microscopic findings confirmed a systemic protozoal infection; however, the organism exhibited characteristics of both N caninum and T gondii. Diagnosis of a T gondii-like infection was based on internal structures of the organism and positive reaction to rabbit polyclonal antibodies to T gondii. Reports of toxoplasmic dermatitis are rare in the cat and dog, and this is the first reported diagnosis of T gondii-like protozoa in skin aspirates.     

Linkage of dermatomyositis in the Shetland Sheepdog to chromosome 35

Dermatomyositis is an inflammatory disease of the skin and muscle and is most commonly found in the Shetland sheepdog. Both the clinical presentation and the age of onset of dermatomyositis vary widely, and the inability to diagnose dermatomyositis before clinical symptoms ensue has made control of the disease difficult. Identification of a genetic marker that cosegregates with dermatomyositis would facilitate the development of a DNA-based test for the early detection of affected dogs. We report the use of linkage disequilibrium (LD) mapping to identify linkage to phenotypic dermatomyositis in the Shetland sheepdog. One marker, microsatellite marker FH3570 on canine chromosome 35, had evidence of LD (P=0.00002). Further studies are necessary to narrow the region harbouring the dermatomyositis locus, identify candidate genes and determine mode of inheritance.