Flashing superluminal components in the jet of the radio galaxy 3C120

A 16-month sequence of radio images of the active galaxy 3C120 with the Very Long Baseline Array reveals a region in the relativistic jet where superluminal components flash on and off over time scales of months, while the polarization angle rotates. This can be explained by interaction between the jet and an interstellar cloud located about 8 parsecs from the center of the galaxy. The cloud, which rotates the polarization direction and possibly eclipses a section of the jet, represents a "missing link" between the ultradense broad-emission-line clouds closer to the center and the lower density narrow-emission-line clouds seen on kiloparsec scales.     

An analysis of self-reported joint pain among New York farmers

Data from the telephone interview portion of the New York State Farm Family Health and Hazard Surveillance Project were used to study the prevalence and predictors of joint pain in a cohort of farmers and farm residents. The participants were owner/operators, workers, and residents from a representative sample of farms from 12 New York counties. A total of 1706 participants completed a telephone interview on musculoskeletal conditions. Joint trouble was defined as self-reported aches, pain, or discomfort in the past year in each of five different joint areas. The 12-month prevalence of joint trouble was: lower back 41%, neck/shoulders 35%, knees 29%, hands/wrists 28%, and hips 15%. Using logistic regression modeling, significant risk factors for joint trouble were identified (p < 0.05). Older age and being female increased the risk of aches, pain, or discomfort in most joints. Being the owner/operator increased the risk of neck/shoulder and lower back trouble, and being a worker increased the risk of neck/shoulder trouble. Doing tractor work was associated with trouble in all five joint areas, and milking was associated with knee trouble. These findings indicate that personal risk factors and the intensity and nature of the farm work contribute to joint trouble. Ergonomic improvements to tractors and milking facilities should be a high priority.     

Impact of glyphosate application on microbial biomass and metabolic activity in a Vertic Argiudoll from Argentina

The widespread use of genetically modified crops tolerant to glyphosate, has strongly promoted the use of this herbicide. This work evaluates the effect of increasing doses of glyphosate on biomass and metabolic activity and metabolic quotient of soil microbiota under controlled conditions. Commercial formulation of glyphosate (48%) was sprayed over a Vertic Argiudoll placed in trays, at doses of 0.48, 0.96, 1.92 and 3.84 L a.i ha^?1. Doses usually applied in the field are between 0.96 and 1.92 L a.i ha^?1. Treatments and control were incubated at 25 °C and 75% of water holding capacity. After 4 and 45 days from glyphosate application, carbon from microbial biomass (C-MB), microbial respiration rate (MR), metabolic quotient (qCO₂), and dehydrogenase activity (DA) were determined. The C-MB at 4 days of incubation did not differ (P < 0.05) between the control and the doses of 0.48 and 0.96 L, while it was significantly lower in the highest doses. After 45 days, C-BM in the dose of 3.84 L was significantly lower than the control. The MR showed significant differences over the time but not between doses. Significant differences were found in qCO₂ between doses in both periods of incubation. Dehydrogenase activity was significantly higher in the treatments with glyphosate than in the control at the beginning of incubation. Treatment with 0.48 L presented the highest value after 45 days, while the dose of 3.84 L had lowest DA. The variables analyzed showed an initial inhibitory effect that affected the microbial cells. However, this effect was temporary at doses equivalent or higher than those usually applied in the field.     

Integrase inhibitors and cellular immunity suppress retroviral replication in rhesus macaques

We describe the efficacy of L-870812, an inhibitor of HIV-1 and SIV integrase, in rhesus macaques infected with the simian-human immunodeficiency virus (SHIV) 89.6P. When initiated before CD4 cell depletion, L-870812 therapy mediated a sustained suppression of viremia, preserving CD4 levels and permitting the induction of virus-specific cellular immunity. L-870812 was also active in chronic infection; however, the magnitude and durability of the effect varied in conjunction with the pretreatment immune response and viral load. These studies demonstrate integrase inhibitor activity in vivo and suggest that cellular immunity facilitates chemotherapeutic efficacy in retroviral infections.     

Juvenile hormone mimics: effect on cirriped crustacean metamorphosis

A synthetic juvenile hormone mimic has been shown to cause premature metamorphosis of the cyprid larva of an acorn barnacle in concentrations as low as 10 parts per billion in filtered seawater. The effect of a juvenile hormone mimic on a crustacean has not previously been demonstrated.     

Temporal and Spatial Variations of Ectoparasites on Cage‐reared Channel Catfish,Ictalurus punctatus,in Tamaulipas,Mexico

Studies in cage‐cultured fish have reported spatial and temporal variations on parasite prevalence; however, most of these studies have been carried out in cold water and marine environments. Channel catfish, Ictalurus punctatus, is the main floating cages‐raised species used in intensive fish culture in Tamaulipas. In Mexico, there are no seasonal reports on fish parasites in this type of cage system. The aim of the present study was to determine the prevalence and mean intensity of ectoparasites of cage‐cultured channel catfish in a year. Fish were sampled bimonthly from six locations in Tamaulipas and measured and evaluated for ectoparasites. Results showed the presence of two gill‐dwelling metazoans, Ligictaluridus floridanus and Ergasilus cerastes and one skin‐dwelling protozoan, Trichodina sp.; a pattern characterized by peaks in prevalence in early autumn for L. floridanus and late autumn for E. cerastes was observed. In addition, geographic location had a significant effect on the prevalence of L. floridanus and E. cerastes. It was also observed that presence of these parasites was not associated with any fish mortality. To our knowledge, this is the first seasonal study on ectoparasite prevalence on channel catfish reared in cages in México.     

Supplementation of maca (Lepidium meyenii) tuber meal in diets improves growth rate and survival of rainbow trout Oncorhynchus mykiss (Walbaum) alevins and juveniles

Maca tuber meal is used in fish diet formulations in Andean trout culture and knowledge of its effects on fish growth is paramount to healthy human food production. In the first experiment with rainbow trout alevins (0.096±0.002 g), starter diets were offered from first feeding until 15 weeks. We formulated high protein content (～60%) semi‐purified starter diets supplemented with 0%, 5%, 10%, or 15% maca tuber meal (control, M‐5, M‐10, and M‐15 respectively). The second feeding trial was conducted with juveniles (1.56±0.02 g) fed one of three diets (control, M‐15, and commercial) for 8 weeks. In the first experiment, fish fed M‐10 and M‐15 diets exhibited significantly higher growth rates than the other dietary groups. Survival was significantly improved in the groups fed diets supplemented with maca tuber meal (60.0–69.2%) in comparison with the group fed a control diet (21.7%). The second experiment showed a higher growth rate in the M‐15 group compared with the control and a commercial diet fed group. Leucocyte numbers were increased by dietary supplementation of maca tuber meal. The findings of the present study suggest that a maca tuber meal inclusion at least 5% improves growth rate, feed utilization, immunity by increased leucocyte number, and survival of rainbow trout alevins and juveniles.     

Utilization of carotenoids from various sources by rainbow trout: muscle colour,carotenoid digestibility and retention

Rainbow trout (Oncorhynchus mykiss) with a mean (sd) weight of 120 (2) g were fed diets supplemented with astaxanthin extracted from the yeast Phaffia rhodozyma (OY1 = 50 mg carotenoids kg^–1 feed, OY2 = 100 mg carotenoids kg^–1 feed), astaxanthin (AX = 100 mg astaxanthin kg^–1 feed) and canthaxanthin (CX = 100 mg canthaxanthin kg^–1 feed) for 4 weeks. Muscle analyses at the end of the experiment indicated a significantly higher carotenoid concentration in the AX group, while CX and OY1 groups were similar in spite of the differences in dietary concentration. The measure of total muscle colour difference (E^* _ab) between initial samples and 4 week ones was higher for the AX fish group but showed no significant difference between OY1, OY2, and CX. The hue and the reflectance ratio (R₆₅₀:R₅₁₀) of fish muscle increased in proportion to carotenoid intake. Digestibility (ADC) of yeast astaxanthin in OY1 and OY2 groups was significantly higher than that in the AX group. Canthaxanthin ADC was about one sixth of that of astaxanthin (AX group). Carotenoid retention in the muscle, expressed as a percentage of carotenoid intake, was higher for the AX group than that recorded for OY1 and OY2. According to ADC, carotenoid retention showed a marked lower value for the CX group. Muscle retentions were similar for astaxanthins from both sources.     

Inheritance of the resistance toMeloidogyne incognita,M. javanica,andM. arenaria in potatoes

The objectives of this research were: 1) to try to determine the inheritance of the resistance toMeloidogyne incognita, M. javanica, andM. arenaria and 2) to study genetic relationships among the three species of root-knot nematodes in potatoes. The source of resistance used wasSolanum sparsipilum. The progenies analyzed in this study may be grouped into a few discrete segregation patterns, three forM. incognita andM. javanica and two forM. arenaria. More than one dominant locus, but not many loci are needed to explain the segregation obtained in the three species. Susceptible clones ofS. sparsipilum possess recessive or epistatic genes which affect the pattern of segregation for resistance, when these clones are crossed to resistant clones. Maternal effects were expressed in reciprocal crosses between susceptible and resistant clones when they were tested for resistance toM. arenaria. Clones in this study which are resistant toM. arenaria are also resistant toM. incognita andM. javanica