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The present study investigates the effect of parametric variations on microstructural and mechanical properties of friction stir welded (FSW) 6 mm thick as-cast AA6061/SiC Aluminum Matrix Composite (AMC) joints. The study has been designed by varying the traverse speed, tool rotational speed and tilt angle up to various levels. Microstructural investigations of welded samples were performed using low-resolution Light Optical Microscopy (LOM) and Scanning Electron Microscopy (SEM). Energy-dispersive X-ray spectroscopy (EDS) is conducted to analyze the chemical composition and reinforcement distribution. To see the effect of parametric variation on mechanical property of the joint, ultimate tensile strength (UTS), percentage (%) elongation and hardness are investigated to support the study. As the optimum parametric values were somewhere missing in context to FSW of AMCs therefore present study deals with carefully deriving optimum weld parameters contributing to both sound weld as well as mechanical properties of the welded specimen. Tool tilt angle played a major role in determining the UTS of the welded specimen besides the tool rotational speed and welding speed making it one of the critical parameter for deciding mechanical properties of the welded specimen.

Nosema pyrausta, an entomopathogenic microsporidium, is an important population regulator of the European corn borer, Ostrinia nubilalis. This manuscript is a review of research on the relationships between N. pyrausta and O. nubilalis. N. pyrausta was described from O. nubilalis in Hungary in 1927 and from O. nubilalis in IA in 1950. It affects the basic biology of O. nubilalis by slowing larval development, reducing percentage pupation, and decreasing adult longevity, oviposition and fecundity. Infections are maintained in a population by vertical and horizontal transmission. Success of vertical transmission depends on intensity of infection. Horizontal transmission is dependent on stage of larval development at time of infection, quantity of inoculum, and host density. Abiotic and biotic factors coupled with N. pyrausta usually have an additive effect in decreasing the fitness of O. nubilalis, i.e., cold temperatures reduce fecundity and increase larval mortality, host plant resistance reduces the number of larvae per plant. Also, microbial and chemical insecticides are more effective in reducing plant feeding if the insect is infected with N. pyrausta. Predators in general feed on N. pyrausta-infected O. nubilalis with no decrease in fitness. Parasitoids do coexist with N. pyrausta, however, parasitoid fecundity is usually reduced when developing in a N. pyrausta-infected host. Previously unreported data are presented on the prevalence of N. pyrausta in O. nubilalis populations from many parts of the US. These data demonstrate that N. pyrausta continues to be present and fluctuate in populations of O. nubilalis as it has since its discovery in the US. Also, the dynamics of its presence remain similar through changes in corn production including crop rotations, reduced tillage and transgenic insect-resistant varieties.

Microprocessor-controlled knee joints appeared on the market a decade ago. These joints are more sophisticated and more expensive than mechanical ones. The literature is contradictory regarding changes in gait and balance when using these sophisticated devices.This study employed a crossover design to assess the comparative performance of a passive mechanical knee prosthesis compared to a microprocessor-controlled knee joint in 15 subjects with an above-knee amputation. Objective measurements of gait and balance were obtained.Subjects demonstrated significantly improved gait characteristics after receiving the microprocessor-controlled prosthetic knee joint (p0.01). Improvements in gait were a transition from a hyperextended knee to a flexed knee during loading response which resulted in a change from an internal knee flexor moment to a knee extensor moment. The participants' balance also improved (p0.01). All conditions of the Sensory Organization Test (SOT) demonstrated improvements in equilibrium score. The composite score also increased.Transfemoral amputees using a microprocessor-controlled knee have significant improvements in gait and balance.

The objective of this study was to determine the susceptibility of the two primary direct insect pests of hazelnuts in Oregon to three species of entomopathogenic nematodes. The entomopathogenic nematodes (Heterorhabditis marelatus Pt. Reyes, Steinernema carpocapsae All and Steinernema kraussei L137) were used in laboratory soil bioassays to determine their virulence against filbertworm, Cydia latiferreana (Walsingham) (Lepidoptera: Tortricidae) and filbert weevil, Curculio occidentalis (Casey) (Coleoptera: Curculionidae). All three nematode species were infective in laboratory bioassays. Infectivity ranged from 73-100% and 23-85% for filbertworm and filbert weevil, respectively. Field results were similar to those found in the laboratory with filbertworm larvae being more susceptible to nematode infection.

Background. Walking is a widely used approach to increase physical activity levels in obese patients. In this paper, we investigate the precision and accuracy of an ankle-worn dual-axis accelerometer (Stepwatch) and investigate its potential application as a predictor of energy expenditure. Methods. Twenty healthy subjects (10 lean, 10 obese) wore spring-levered (Accusplit), piezoelectric (Omron HF-100), and Stepwatch pedometers. Subjects walked on a treadmill at 1, 2, and 3 mph and in a hallway at 1 and 1.85 mph, during which energy expenditure was measured. Results. The Stepwatch counted 99.7 ± 0.67% (mean ± SEM) of the manual counts. In comparison, the Omron pedometer counted 61 ± 3.3% and the Accusplit counted 26 ± 2.8% of the manual counts at 1 mph although all pedometers were accurate (> 98% of counts) at 3 mph. In repeated measures, the Stepwatch produced negligible variance (SD = 0.36) over all speed whereas the other pedometers showed a large amount of variance at all speed (SD = 4–13). Stepwatch counts were predictive of walking energy expenditure corrected by weight (r2 > 0.8). Conclusion. The counts from the Stepwatch were virtually identical to the manual counts from a trained investigator and provided a reliable predictor of walking energy expenditure.

Laboratory soil bioassays were performed at economic field rates for in-furrow (3.85 × 106 spores/g dry soil) and broadcast (3.85 × 105 spores/g dry soil) applications with three isolates of Metarhizium anisopliae (F52, ATCC62176, and ARSEF5520) and one isolate of Beauveria bassiana (GHA). All isolates tested were infective to second instar Delia radicum (L.). The conditionally registered M. anisopliae isolate (F52) performed best killing an average of 85 and 72% of D. radicum larvae at the high and low concentration, respectively. The mean LC50 and LC95 of F52 against second instar D. radicum was 2.7 × 106 and 1.8 × 108 spores/g dry soil, respectively. The use of F52 in an integrated management program is discussed.

Wholesale container-grown ornamentals are often maintained at the nursery for at least two growing seasons and are subject to infestation by black vine weevil (BVW), Otiorhynchus sulcatus F., for several months each year. Therefore, a potting media amendment aimed at controlling BVW needs to persist for an extended period of time. These studies were conducted to determine the persistence and ecology of Metarhizium anisopliae (MetchnikoV) Sorokin incorporated into peat and bark-based potting media with and without a crab meal amendment in container-grown Picea abies ‘Nidiformis.’ Rooted cuttings of P. abies were planted into potting media amended with M. anisopliae (1 g of formulated product/L; »6 log10 CFU/g dry potting media). The fungal population in bulk potting media was quantitatively determined using selective media at 14, 21, 28, 35, 49, 63, 77, 91, 105, 119, 143, 175, 203, 231, 258, 287 and 342 days. The fungal population in the rhizosphere was quantitatively determined at 203, 231, 258, 287, and 342 days. M. anisopliae colonized the rhizosphere of P. abies and the fungal population in the rhizosphere was signiWcantly greater than in the surrounding bulk media. M. anisopliae persisted in the peat and bark-based potting media at 6.22 and 5.74 log10 CFU/g dry potting media for 342 days, respectively. Bioassays using bark and peat-based potting media inoculated with M. anisopliae at 6 log 10 CFU/g dry potting media resulted in 93.5% and 97.5% infection of last instar BVW, respectively. P. abies roots inoculated with M. anisopliae infected 76% of 2nd–3rd instar BVW. Inoculation of roots with M. anisopliae represents a novel method for delivering entomopathogenic fungi and would greatly reduce application costs. Factors associated with fungal biology outside the host may be more important than virulence in a laboratory bioassay.

The purpose of this study was to quantify electromyographic (EMG) activity in the immobilized shoulder girdle musculature at rest and during a battery of contralateral upper limb activities. Six asymptomatic men, aged 22 to 33 years, volunteered to participate. Fine-wire (supraspinatus, infraspinatus) and surface (deltoids, trapezii, biceps, serratus anterior) electrodes recorded the mean peak normalized (percent maximal voluntary contraction [%MVC]) EMG activity from each immobilized muscle at rest and during slow, fast, and incrementally resisted contralateral upper limb motions (5, 15, and 25 lb). EMG activity in all muscles was low during quiet immobilized standing (1.5% maximal voluntary contraction [MVC]). During slow contralateral upper limb motions, activity ranged from 0.7% to 51.6% MVC (highest in trapezii) and was less than 15% MVC in the supraspinatus, infraspinatus, and anterior deltoid. Bimanual jar opening increased biceps activity from 7.8% to 16.1% MVC. During fast contralateral upper limb motions, peak infraspinatus activity increased to 56.7% during a fast straightforward reach. Supraspinatus activity was relatively high during all resisted backward-pulling motions (25.2%-32.1% MVC), whereas resisted forward reaching produced relatively little activity in the anterior deltoid, supraspinatus, infraspinatus, or biceps. Several slow and fast motions produced high trapezius activity (45% MVC) with low supraspinatus, biceps, and anterior deltoid activities (10% MVC). Our findings suggest that (1) immobilized shoulder girdle muscle EMG activity during quiet standing is negligible in asymptomatic individuals; (2) contralateral upper limb motions at self-selected speeds are not likely to be harmful to healing tissues; (3) during early healing periods, patients with biceps-labral injury should minimize bimanual activities, those with supraspinatus injury should avoid backward-pulling motions, and those with infraspinatus injury should avoid fast straightforward reaches; and (4) cross-body, straightforward, or downward reaches at either a slow or fast speed may be appropriately prescribed as rehabilitative exercises that can be initiated while the shoulder remains immobilized.

Smith J, Padgett DJ, Kaufman KR, Harrington SP, An K-N, Irby SE. Rhomboid muscle electromyography activity during 3 different manual muscle tests. Arch Phys Med Rehabil 2004;85:987–92. Objective To determine which of 3 previously published rhomboid manual muscle tests (MMTs) elicits the maximal rhomboid electromyographic activity in an asymptomatic population. Design Criterion standard. Setting Motion analysis laboratory at tertiary care medical center. Participants Eleven male volunteers (age range, 24–40y) without shoulder or neck pain. Interventions Not applicable. Main outcome measures Peak 1-second normalized electromyographic activity in the rhomboid muscle during 8 different MMT positions, including 3 different rhomboid MMT positions (Kendall, Kendall-Alternative, Hislop-Montgomery). Results The Kendall MMT (78% maximal voluntary contraction [MVC]) produced higher rhomboid electromyographic activity than the Kendall-Alternative (71% MVC) or the Hislop-Montgomery MMT (52% MVC), but the differences were not statistically significant. The posterior deltoid MMT generated the greatest rhomboid electromyographic activity of all MMTs, and 4% to 30% greater rhomboid electromyographic activity than the 3 rhomboid MMTs ( P =.0001; posterior deltoid > Hislop-Montgomery). Electromyographic profiles of the Kendall and Kendall-Alternative MMTs were similar, whereas the Hislop-Montgomery MMT produced less upper trapezius activity ( P =.0001 vs Kendall and Kendall-Alternative) and more latissimus dorsi activity ( P =.0001 vs Kendall-Alternative). The standard MMT positions for the middle trapezius, levator scapula, posterior deltoid, and latissimus dorsi produced the maximal electromyographic activity for their respective target muscles. Conclusions The posterior deltoid MMT position should be used to produce maximal rhomboid electromyographic activity for normalization purposes during kinesiologic studies. The Kendall and Kendall-Alternative rhomboid MMT are likely to be clinically indistinct. It is unlikely that clinicians can use standard MMT positions to distinguish rhomboid strength from synergists, such as the levator scapula and middle trapezius muscle, for diagnostic purposes.

The entomopathogenic fungus Beauveria bassianainfects a wide range of insects and survives as a soil saprophyte and a plant endophyte. The objective of our study was to determine the role of rainfall in dispersing B. bassiana(Balsamo) Vuillemin to the surface of corn (Zea mays) from soil with different levels of crop residue. Laboratory studies which simulated field tillage systems, had levels of crop residue which covered 0.53 (control), 34, 59 and 84% of the soil surface. Simulated rainfall in a raindrop tower at an intensity of 73 mm/h caused a significant increase in the mean number of B. bassianacolony forming units (CFU) isolated from the surface of corn plants. Plants receiving rain had a mean (±S.E.M.) of 8.8 ± 2.8 CFU per plant; controls had a mean of 0.03 ± 0.01 CFU per plant. The mg of soil collected from the surface of plants also was significantly influenced by rainfall. Plants receiving rain had a mean of 15 .7 ± 1.7 mg of soil per plant while controls had a mean of 3.4 ± 0.4 mg of soil per plant. Linear regression revealed highly significant negative relationships between the mean mg of soil and the mean number of CFU per plant, over the four levels of crop residue. The amount of soil and number of CFU per plant decreased significantly with increasing levels of crop residue. In field studies with conservation- and no-till systems, results were similar to those recorded in the raindrop tower. The mean number of CFU and mg of soil per plant were both higher in conservation-till plots than in no-till plots, where surface residue averaged 45 and 95%, respectively. Rainfall plays an active role in the dispersal of B. bassianafrom the soil environment to the surface of whorl-stage corn. Increased levels of crop residue reduce the amount of soil and fungal transfer to the surface of young corn. © 2002 Elsevier Science B.V. All rights reserved.

Nosema pyrausta is an obligate pathogen causing reduced fecundity and longevity of Ostrinia nubilalis. This study was conducted to determine the combined effects of N. pyrausta infection and temperature on O. nubilalis egg production and hatch. N. pyrausta-infected and noninfected O. nubilalis were maintained in two different temperature regimes. The first regime allowed females to oviposit under optimum conditions (27 degrees C, 65% RH, 16:8 (L:D)), while females in the second regime were held initially under the same humidity and light conditions, but a constant temperature of 16 degrees C for 1 week after which they were transferred to optimum ovipositional conditions. Studies were performed initially with O. nubilalis populations and later with individual mating pairs. In studies with O. nubilalis populations, the mean number of eggs laid per female under optimum conditions was 660, while N. pyrausta-infected females held initially at 16 degrees C laid 116 eggs per female. In studies with individual mating pairs, N. pyrausta infection reduced egg production per female 53 and 11% in the 16 and 27 degrees C temperature regimes, respectively, compared to noninfected females under optimum conditions. Exposure to 16 degrees C temperatures early in the ovipositional period had a more profound impact on reducing egg production in N. pyrausta-infected than noninfected O. nubilalis.

Invasive cytology of the thoracic and abdominal cavities can provide diagnostic information in a timely manner for the practitioner. The information depends on obtaining a quality sample followed by thorough cytologic evaluation. As an adjunct to the historical and clinical information, cytology is valuable in establishing a diagnosis or a list of differentials and directing future diagnostics or therapy. The application of cytology of internal organs opens a new window for the differential diagnosis of disease.