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Di-n-butyl phthalate (DBP) is a phthalate used in the manufacture of consumer products such as plastics and personal care products. Widespread exposure in the population occurs throughout life, including during pregnancy and lactation. Because limited data are available in both animals and humans to evaluate DBP as a human carcinogen, the National Toxicology Program conducted 2-year studies of DBP in rats and mice. Time-mated female Sprague Dawley (Hsd:Sprague Dawley SD) rats were exposed to 0, 300, 1,000, 3,000, or 10,000 ppm DBP in feed during gestation and lactation. Postweaning, F1 offspring consumed diets with the same exposure concentrations as the dam for 2 years (n = 50/sex/exposure group). Male and female adult B6C3F1/N mice were exposed to 0, 1,000, 3,000, or 10,000 ppm DBP in feed for 2 years (n = 50/sex/exposure group). Estimated average chronic chemical consumption was 16-17, 54-57, 152-169, and 510-600 mg DBP/kg body weight/day (mg/kg/day) in rats in the 300, 1,000, 3,000, and 10,000 ppm groups, respectively, and 105-112, 329-347, and 1,306-1,393 mg/kg/day in mice in the 1,000, 3,000, and 10,000 ppm groups, respectively. (Abstract Abridged).

Aspergillus fumigatus is a thermotolerant, soil-borne fungal species that is ubiquitous in the environment. Mold was nominated to the National Toxicology Program (NTP) by a private individual due to suspected adverse health effects associated with personal exposure in indoor and occupational settings. A. fumigatus is of particular concern in the biowaste industry as the species can contaminate self-heating compost piles. Because of this potential for personal and occupational exposure and the lack of available toxicity data, toxicity studies were conducted in which male and female B6C3F1/N mice were exposed to A. fumigatus conidia (spores) two times a week for 3 months. All in-life procedures, including inhalation exposure, test article preparation, and hematology analysis, were completed by the National Institute for Occupational Safety and Health (NIOSH, Morgantown, WV). Battelle (Columbus, OH) conducted terminal necropsies, measured terminal body and organ weights, and evaluated gross lesions on-site at NIOSH. Tissue processing and histopathology were completed at Battelle. Grocott's methenamine silver (GMS) staining was performed at NIOSH. Genetic toxicology studies on mouse peripheral blood erythrocytes were conducted by Integrated Laboratory Systems, LLC (Research Triangle Park, NC). (Abstract Abridged).

Despite the cessation of its production and use in many parts of the world, hexachlorobenzene (HCB) remains highly persistent in the environment, and chronic, low-dose exposure to HCB in humans continues. Its structural resemblance to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), ability to activate the aryl hydrocarbon (Ah) receptor, TCDD-like toxicities, and bioaccumulative nature suggest HCB be included in the toxic equivalency factor (TEF) methodology. Consequently, the National Toxicology Program conducted this subchronic study of HCB, including measurement of a variety of toxicological and biochemical endpoints, to allow comparison to TCDD data obtained in a previous 2-year bioassay. (Abstract Abridged).

p-Chloro-α,α,α-trifluorotoluene is a solvent used in paints and coatings and as an industrial intermediate in the production of other chemicals (e.g., herbicides, dyes, pharmaceuticals). p-Chloro-α,α,α-trifluorotoluene was nominated for study by the National Cancer Institute and Kowa American Corporation for study because of its high import volume and lack of occupational exposure limits. Male and female Hsd:Sprague Dawley SD rats and B6C3F1/N mice were exposed to p-chloro-α,α,α-trifluorotoluene (purity greater than 99.5%) by inhalation for 3 months or 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Escherichia coli, and rat and mouse peripheral blood erythrocytes. (Abstract Abridged).

2,3-Butanedione is commonly used by the flavor manufacturing industry for production of artificial flavor formulations. Examples of flavored food products include popcorn, cake mixes, flour, beer, wine, margarines and soft spreads, cheese, candy, bakery products, crackers, cookies, ice cream, frozen foods, and many other food and beverage products. 2,3-Butanedione was nominated by the United Food and Commercial Workers Union for long-term inhalation studies due to outbreaks of bronchiolitis obliterans in workers exposed to its vapors. Male and female Wistar Han [Crl:WI(Han)] rats and B6C3F1/N mice were exposed to 2,3-butanedione (greater than or equal to 98.5%) by inhalation for 3 months or 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium and Escherichia coli, mouse bone marrow cells, and rat and mouse peripheral blood erythrocytes. (Abstract Abridged).

TRIM VX is a metalworking fluid used as a lubricant and coolant liquid and for cleaning tools and parts during cutting, drilling, milling, and grinding. The metalworking fluid class was nominated by the National Institute for Occupational Safety and Health (NIOSH) for study by the National Toxicology Program because of high production volumes, the large number of occupationally exposed workers, the lack of carcinogenicity and chronic toxicology data, and because epidemiologic data indicate an increased incidence of laryngeal cancer in workers exposed to metalworking fluids. TRIM VX was selected as an example soluble oil metalworking fluid following chemical analysis and collaboration with NIOSH. Male and female Wistar Han [Crl:WI (Han)] rats and B6C3F1/N mice were exposed to TRIM VX by inhalation for 3 months or 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Escherichia coli, and rat and mouse peripheral blood erythrocytes. (Abstract Abridged).

Tetrabromobisphenol A is a flame retardant used in epoxy resin circuit boards, in electronic enclosures (of polycarbonate-acrylonitrile-butadiene-styrene plastics), in paper, and in textiles. It may also be used as a chemical intermediate for the synthesis of other flame retardants. Tetrabromobisphenol A was nominated by the NIEHS for toxicity and carcinogenicity studies based on its high production volume, the potential for widespread human exposures, and the absence of standard toxicity and carcinogenicity studies reported in the scientific literature. Male and female F344/NTac rats and B6C3F1/N mice were administered tetrabromobisphenol A (purity of greater than 99%) in corn oil by gavage for 3 months, and male and female Wistar Han [Crl:WI(Han)] rats (referred to as Wistar Han rats) and B6C3F1/N mice were administered tetrabromobisphenol A (purity of approximately 99%) in corn oil by gavage for 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Escherichia coli, and mouse peripheral blood erythrocytes. (Abstract Abridged).

CIMSTAR 3800 is a metalworking fluid used as a lubricant and coolant liquid on the surface of the worked piece to remove heat and fine swarf and to provide corrosion inhibition at the newly cut surface. CIMSTAR 3800 is used in the general machining and grinding of automotive aluminum parts and on light to moderate machining and grinding of light steel, stainless steels, hardened steels, and other materials. CIMSTAR 3800 was nominated by the National Institute for Occupational Safety and Health for study by the National Toxicology Program because of its high production volume, the large number of occupationally exposed workers, the lack of carcinogenicity and chronic toxicology data, and because epidemiologic data indicate an increased incidence of laryngeal cancer in workers exposed to metalworking fluids. Male and female F344/NTac rats and B6C3F1/N mice were exposed to CIMSTAR 3800 by inhalation for 3 months, and male and female Wistar Han [Crl:WI (Han)] rats (referred to as Wistar Han rats) and B6C3F1/N mice were exposed to CIMSTAR 3800 by inhalation for 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Escherichia coli, and rat and mouse peripheral blood erythrocytes. (Abstract Abridged).

5-Amino-o-cresol is used as an oxidative dye coupler (secondary intermediate) or oxidative (permanent) in hair dye formulations. It was nominated for study by the National Cancer Institute because it is a widely used genotoxic hair dye component for which no cancer studies have been reported. Male and female F344/NTac rats and B6C3F1/N mice were administered 5-amino-o-cresol (greater than 99% pure) dermally for 3 months. Genetic toxicology studies were conducted in Salmonella typhimurium, peripheral blood erythrocytes of male and female mice, and bone marrow of male mice. (Abstract Abridged).

Octahydro-tetramethyl-naphthalenyl-ethanone (OTNE) is a fragrance ingredient that is formed as a mixture of isomers with a basic unsaturated alkyl cyclic ketone structure. The main isomer is 1-(1,2,3,4,5,6,7,8-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone (β-isomer). Two other predominant isomers within the mixture are 1-(1,2,3,4,6,7,8,8a-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone (α-isomer) and 1-(1,2,3,5,6,7,8,8a-octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)ethanone (γ-isomer). OTNE is used as a perfume ingredient in soap, shampoo, cologne, liquid detergent compounds, and malodor-reducing compounds. Male and female F344/NTac rats and B6C3F1/N mice were administered OTNE (greater than 92.3% pure with respect to the 3 prominent isomers) dermally for 3 months. Genetic toxicology studies were conducted in Salmonella typhimurium, Escherichia coli, and rat and mouse peripheral blood erythrocytes. (Abstract Abridged).

Fullerene C60 (C60), a primary allotrope of carbon, is used in a variety of consumer applications including microelectronics, photovoltaics, batteries and fuel cells, and water treatment methods. Human exposure to engineered C60 due to industrial applications may occur via inhalation, oral, dermal, or parenteral routes. In these toxicity and tissue burden studies, male and female Wistar Han rats and B6C3F1/N mice were exposed to fullerene C60 (at least 95% pure) via nose-only inhalation for 3 months. Two different C60 fullerene aggregate sizes, 1 µm diameter (micro-C60) and 50 nm diameter (nano-C60) were studied to assess the potential for differential effects based on particle size. (Abstract Abridged).

Abrasive blasting, commonly known as sandblasting, involves forcibly projecting a stream of abrasive particles through compressed air or steam against a surface to change its quality or to remove contaminants. Silica blasting sand contains high levels of crystalline silica--which can cause pulmonary fibrosis (silicosis) after exposure through inhalation and is considered a lung carcinogen--and constitutes approximately 63% of all abrasives used in abrasive blasting. Other abrasives, including specular hematite, are recommended as alternative blasting agents. Due to the health risks associated with using blasting sand in the abrasive blasting process and the lack of toxicity data on alternatives to blasting sand, the National Institute for Occupational Safety and Health (NIOSH) proposed testing blasting sand and alternative abrasives to characterize their associated toxicity. (Abstract Abridged).

De Witt, JK, English, KL, Crowell, JB, Kalogera, KL, Guilliams, ME, Nieschwitz, BE, Hanson, AM, and Ploutz-Snyder, LL. Isometric midthigh pull reliability and relationship to deadlift one repetition maximum. J Strength Cond Res 32(2): 528-533, 2018-The purpose of this investigation was to examine the reliability of the isometric midthigh pull (IMTP) and the relationship between IMTP peak force and deadlift 1 repetition maximum (1RM). Nine subjects (5 men and 4 women; 40.6 ± 8.0 years; 1.72 ± 0.10 m; 75.6 ± 13.4 kg) participated in this study. Isometric midthigh pull and deadlift 1RM were both performed during 2 testing sessions. For IMTP, peak force and peak rate of force development (RFD) were determined, in addition to RFD at 30 ms, 50 ms, 90 ms, 150 ms, 200 ms, and 250 ms after initiation of the pull. Intraclass correlation coefficients (ICCs) were calculated to evaluate the reliability of IMTP measures. Pearson product-moment correlations and linear regression were used to determine associations between IMTP and deadlift 1RM. Isometric midthigh pull peak force was reproducible both within (ICC = 0.98 and 0.97) and between sessions (ICC = 0.89) and significantly correlated with deadlift 1RM (r = 0.88, p ≤ 0.05), but intermediate force outputs and RFD were not. Lack of associations between RFD and deadlift 1RM indicate that the ability to create explosive force may be independent of the ability to create maximal force. The strong relationship between IMTP peak force and deadlift 1RM was present regardless of which IMTP repetition across the 2 sessions was examined. Peak force generated during IMTP is a reliable method to assess full body maximal strength. A single IMTP repetition, provided adequate familiarization and warm-up, correlates strongly with deadlift 1RM. Practitioners can use the IMTP test as a method to estimate maximal deadlift strength in a quick and potentially less provocative manner than traditional 1RM testing.

Contains fulltext : 182174.pdf (Publisher’s version ) (Open Access) Recent advancements in transnasal endoscopy enable a shift in diagnostic workup of lesions in the pharynx and larynx, from an examination with biopsy under general anesthesia to an office-based examination with flexible endoscopic biopsy under topical anesthesia. Procedural complications were evaluated to assess the safety of office-based flexible endoscopic biopsy in patients with benign and malignant laryngopharyngeal lesions. Patients who underwent flexible endoscopic biopsy from 2012 to 2016 were evaluated retrospectively. Complications were classified using the Clavien-Dindo classification of surgical complications. A total of 201 flexible endoscopic biopsies were performed in 187 patients. Two Clavien-Dindo grade I (laryngospasm and anterior epistaxis), one grade II (laryngeal bleeding), and one grade IIIb (laryngeal edema) complication were observed. The first complication was self-limiting and the other three required an intervention. All patients fully recovered without sequelae. Flexible endoscopic biopsy appears to be a safe office-based procedure for the diagnosis of benign and malignant laryngopharyngeal lesions.

Relationships between sprinting speed, body mass, and vertical jump kinetics were assessed in 243 male soccer athletes ranging from 10-19 years. Participants ran a maximal 36.6 meter sprint; times at 9.1 (10 y) and 36.6 m (40 y) were determined using an electronic timing system. Body mass was measured by means of an electronic scale and body composition using a 3-site skinfold measurement completed by a skilled technician. Countermovement vertical jumps were performed on a force platform - from this test peak force was measured and peak power and vertical jump height were calculated. It was determined that age (r=-0.59; p

Introduction International Space Station (ISS) crewmembers perform muscle strength and endurance testing pre- and postflight to assess the physiologic adaptations associated with long-duration exposure to microgravity. However, a reliable and standardized method to document strength changes in-flight has not been established. To address this issue, a proprietary dynamometer, the Muscle Atrophy Research and Exercise System (MARES) has been developed and flown aboard the ISS. The aims of this ground-based investigation were to: (1) evaluate the test–retest reliability of MARES and (2) determine its agreement with a commercially available isokinetic dynamometer previously used for pre- and postflight medical testing. Methods Six males (179.5±4.7 cm; 82.0±8.7 kg; 31.3±4.0 yr) and four females (163.2±7.3 cm; 63.2±1.9 kg; 32.3±6.8 yr) completed two testing sessions on a HUMAC NORM isokinetic dynamometer (NORM) and two sessions on MARES using a randomized, counterbalanced, cross-over design. Peak torque values at 60° and 180° s −1 were calculated from five maximal repetitions of knee extension (KE) and knee flexion (KF) for each session. Total work at 180° s −1 was determined from the area under the torque versus displacement curve during 20 maximal repetitions of KE and KF. Results Intraclass correlation coefficients were relatively high for both devices (0.90–0.99). Only one dependent measure, KE peak torque at 60° s −1 exhibited good concordance between devices ( ρ =0.92) and a small average difference (0.9±17.3 N m). Conclusion MARES demonstrated acceptable test–retest reliability and thus should serve as a good tool to monitor in-flight strength changes. However, due to poor agreement with NORM, it is not advisable to compare absolute values obtained on these devices.

The purpose of this study was to compare motions of soccer players in the English Premier (1st) and Championship (2nd) League. A total of 26 449 observations were obtained from players during 4 seasons (2006-2010) in the 2 leagues. Time-motions of all players (attackers, central defenders, central midfielders, wide defenders, wide midfielders) were recorded during each match using the Prozone® System, (Leeds, UK), and categorized by speed intensity. Number of actions, total distance and the mean distance covered at each speed intensity were measured. Players in the Championship league covered a total match distance of 11.1±0.9 km compared with 10.8±1.0 km for players from the Premiership (p0.001). Championship players also covered greater distances during jogging, running, high-speed running, and sprinting. Premiership players covered more distance walking. Players in the Soccer League Championship had more instances of each condition. Although these differences were statistically significant, they were negligible in practical terms, suggesting match-related activities do not explain the general superiority of Premiership players over Championship players in England.

The purpose of this study was to develop and validate a regression equation to estimate peak power (PP) using a large sample of athletic youths and young adults. Anthropometric and vertical jump ground reaction forces were collected from 460 male volunteers (age: 12-24 years). Of these 460 volunteers, a stratified random sample of 45 subjects representing 3 different age groups (12-15 years [n = 15], 16-18 years [n = 15], and 19-24 years [n = 15]) was selected as a validation sample. Data from the remaining 415 subjects were used to develop a new equation ("Novel") to estimate PP using age, body mass (BM), and vertical jump height (VJH) via backward stepwise regression. Independently, age (r = 0.57), BM (r = 0.83), and VJ (r = 0.65) were significantly (p0.05) correlated with PP. However, age did not significantly (p = 0.53) contribute to the final prediction equation (Novel): PP (watts) = 63.6 × VJH (centimeters) + 42.7 × BM (kilograms) - 1,846.5 (r = 0.96; standard error of the estimate = 250.7 W). For each age group, there were no differences between actual PP (overall group mean ± SD: 3,244 ± 991 W) and PP estimated using Novel (3,253 ± 1,037 W). Conversely, other previously published equations produced PP estimates that were significantly different than actual PP. The large sample size used in this study (n = 415) likely explains the greater accuracy of the reported Novel equation compared with previously developed equations (n = 17-161). Although this Novel equation can accurately estimate PP values for a group of subjects, between-subject comparisons estimating PP using Novel or any other previously published equations should be interpreted with caution because of large intersubject error (±600 W) associated with predictions.

INTRODUCTION: The effect of reducing gravity on locomotion has been studied using microgravity analogues. However, there is no known literature comparing locomotion in actual microgravity (AM) to locomotion in simulated microgravity (SM). METHODS: Five subjects were tested while walking at 1.34 m x s(-1) and running at 3.13 m x s(-1) on a treadmill during parabolic flight and on a microgravity simulator. The external load (EL) in AM and SM was provided by elastomer bungees at approximately 55% (low) and 90% (high) of the subjects' bodyweight (BW). Lower body joint kinematics and ground reaction forces were measured during each condition. Effect size and its 95% confidence interval were computed between gravitational conditions for each outcome variable. RESULTS: In AM, subjects attained approximately 15-21 degrees greater hip flexion during walking and 19-25 degrees greater hip flexion during running. Hip range of motion was greater in AM during running by approximately 12-17 degrees. Trunk motion was 4 degrees less in SM than AM during walking. Peak impact force was greater in SM than in AM during walking with a low EL (SM = 0.95 +/- 0.04 BW; AM = 0.76 +/- 0.04 BW) and contact times were greater in SM. CONCLUSIONS: Subtle differences exist in locomotion patterns, temporal kinematics, and peak impact ground reaction forces between AM and SM. The differences suggest possible adaptations in the motor coordination required between gravitational condition, and potential differences in adaptations that are dependent upon if training occurs in actual or simulated microgravity. Language: en

Treadmill exercise is commonly used for aerobic and anaerobic conditioning. During non-motorized treadmill exercise, the subject must provide the power necessary to drive the treadmill belt. The purpose of this study was to determine what factors affected the time to fatigue on a pair of non-motorized treadmills. Twenty subjects (10 males/10 females) attempted to complete five minutes of locomotion during separate trials at 3.22, 4.83, 6.44, 8.05, 9.66, and 11.27 km (raised dot) h(sup -1). Total exercise time (less than or equal to 5 min) was recorded. Exercise time was converted to the amount of 15 second intervals completed. Peak oxygen uptake (VO2) was measured using a graded exercise test on a standard treadmill, and anthropometric measures were collected from each subject before entering into the study. A Cox proportional hazards regression model was used to determine significant predictive factors in a multivariate analysis. Non-motorized treadmill speed and absolute peak VO2 were found to be significant predictors of exercise time, but there was no effect of anthropometric characteristics. Gender was found to be a predictor of treadmill time, but this was likely due to a higher peak VO2 in males than in females. These results were not affected by the type of treadmill tested in this study. Coaches and therapists should consider the cardiovascular fitness of an athlete or client when prescribing target speed since these factors are related to the total exercise time than can be achieved on a non-motorized treadmill.

Die Behandlung der traumatischen vorderen Schulterinstabilitat hat in den vergangenen 2 Jahrzehnten haufig kontroverse Diskussionen verursacht. Einigkeit herrscht jedoch uber die Notwendigkeit einer dem Verletzungsmechanismus, dem Auspragungsgrad der vorliegenden Instabilitat und dem Funktionsanspruch des Patienten in Bezug auf Beruf und Sport individuell angepassten Behandlung. Die offene Rekonstruktion des ventralen Kapsel-Labrum-Komplexes galt uber lange Jahre als Therapie der Wahl. Mittlerweile zeigen die Ergebnisse nach arthroskopischer Kapsel-Labrum-Refixation eine zunehmende Annaherung an die Ergebnisse der offenen Techniken. Insbesondere durch den Einsatz von Fadenankern scheint es moglich, die Prinzipien der klassischen offenen Bankart-Operation zu imitieren und so die allgemeinen Vorteile arthroskopischer Operationstechniken mit einer niedrigen Rezidivrate zu kombinieren.

The idiopathic scoliosis is a three dimensional spinal deformity mostly occurring in female adolescents. Untreated it can progress and result in back pain, impaired lung capacity and psychosocial disorders due to the cosmetic appearance of the deformed trunk. The treatment depends on the severity of the curve and ranges from physiotherapy and observation, brace treatment to surgical treatment with partial correction and fusion of the primary curve. Patients with an idiopathic scoliosis should be encouraged to actively take part in sports activities. Positive influences on the general fitness including the lung function, on the trunk muscles and on the psyche can be expected. There are no scientific data indicating that any kind of sport activities alter the natural history of idiopathic scoliosis.

PURPOSE Aim of this study was to compare the results of the surgical repair of full-thickness rotator cuff tears with and without resection of the lateral clavicle. METHODS 102 patients were retrospectively observed by an independent observer for a mean follow-up of 21 months (12 - 42). 93 patients had medium to large sized tears (1 - 5 cm) and 9 had massive tears (> 5 cm). Additional resection of the lateral end of the clavicle was performed in 20 patients. The mean age of the 68 men and 34 woman was 57.3 years (28 - 80). For the evaluation the Constant score, the ASES score and the visual analogue scales for postoperative satisfaction, function, strength, pain and ADL were used. RESULTS The subjective results were good to excellent in 79 patients (76 %), fair in 14 patients (13.7 %) and poor in 9 patients (8.9 %), too. After surgery the Constant score was 87 % of the contralateral side for all patients, 89 % for group I and 84 % for group II and the mean ASES score was 86 %, 87 % and 82 % of the contralateral side. Comparing the pre- and post-operative values on the visual analogue scale pain and disability in ADL were decreased highly significantly in all patients (p < 0.001). CLINICAL RELEVANCE We conclude that in patients with a full-thickness rotator cuff tear the patient's satisfaction and function will improve after acromioplasty and rotator cuff repair. The results are not significantly influenced by an additional resection of the lateral clavicle.

Quantifying the preferred transition speed (PTS) from walking to running has provided insight into the underlying mechanics of locomotion. The dynamic similarity hypothesis suggests that the PTS should occur at the same Froude number across gravitational environments. In normal Earth gravity, the PTS occurs at a Froude number of 0.5 in adult humans, but previous reports found the PTS occurred at Froude numbers greater than 0.5 in simulated lunar gravity. Our purpose was to (1) determine the Froude number at the PTS in actual lunar gravity during parabolic flight and (2) compare it with the Froude number at the PTS in simulated lunar gravity during overhead suspension. We observed that Froude numbers at the PTS in actual lunar gravity (1.39±0.45) and simulated lunar gravity (1.11±0.26) were much greater than 0.5. Froude numbers at the PTS above 1.0 suggest that the use of the inverted pendulum model may not necessarily be valid in actual lunar gravity and that earlier findings in simulated reduced gravity are more accurate than previously thought.

INTRODUCTION Crewmembers performing treadmill exercise on the International Space Station must wear a harness with an external gravity replacement force that is created by elastomer bungees. The quantification of the total external force, displacement, stiffness, and force variation is important for understanding the forces applied to the crewmember during typical exercise. METHODS Data were collected during static trials in the laboratory from a single subject and four subjects were tested while walking at 1.34 m x s(-1) and running at 2.24 m x s(-1) and 3.13 m x s(-1) on a treadmill during simulated microgravity in parabolic flight. The external force was provided by bungees and carabiner clips in configurations commonly used by crewmembers. Total external force, displacement, and force variation in the bungee system were measured, from which stiffness was computed. RESULTS Mean external force ranged from 431 to 804 N (54-131% bodyweight) across subjects and conditions. Mean displacement was 4 to 8 cm depending upon gait speed. Mean stiffness was affected by bungee configuration and ranged from 1.73 to 29.20 N x cm(-1). Force variation for single bungee configurations was 2.61-4.48% of total external force and between 4.30-57.5% total external force for two-bungee configurations. CONCLUSIONS The external force supplied to crewmembers by elastomer bungees provided a range of loading levels with variations that occur throughout the gait cycle. The quantification of bungee-loading characteristics is important to better define the system currently used by crewmembers during exercise.

Astronauts perform treadmill exercise during long-duration space missions to counter the harmful effects of microgravity exposure upon bone, muscle, and cardiopulmonary health. When exercising in microgravity, astronauts wear a harness and bungee system that provides forces that maintain attachment to the treadmill. Typical applied forces are less than body weight. The decreased gravity-replacement force could result in differences in ground-reaction force at a given running speed when compared to those achieved in normal gravity, which could influence the adaptive response to the performed exercise. Seven astronauts (6 m/1 f) who completed approximately 6-month missions on the International Space Station (ISS) completed a preflight (1 G ) and multiple in-flight (0 G ) data collection sessions. Ground-reaction forces were measured during running at speeds of 8.0 kph and greater on an instrumented treadmill in the lab and on the ISS. Ground-reaction forces in 0 G were less than in 1 G for a given speed depending upon the gravity-replacement force, but did increase with increased speed and gravity-replacement force. Ground-reaction forces attained in 1 G during slower running could be attained by increasing running speed and/or increasing gravity-replacement forces in 0 G . Loading rates in 1 G , however, could not be replicated in 0 G . While current gravity-replacement force devices are limited in load delivery magnitude, we recommend increasing running speeds to increase the mechanical loads applied to the musculoskeletal system during 0 G treadmill exercise, and to potentially increase exercise session efficiency.

Loss of muscle mass due to reduced mechanical loading is a critical issue for long duration spaceflight on the International Space Station (ISS) [1]. To address this issue, NASA has developed the Advanced Resistive Exercise Device (ARED) that allows astronauts to perform resistance exercise on the ISS. To minimize force transmission to the ISS, the ARED is mounted to a vibration isolation system (VIS). During squat exercise, ARED rotates relative to the ISS, functioning like a nutcracker to compress the astronaut with a load provided by two vacuum cylinders. Though the ARED is an effective exercise countermeasure device, the extent to which squat exercise on the ISS achieves Earth-equivalent muscle moments remains unknown.Copyright © 2013 by ASME

Trimethylolpropane triacrylate (TMPTA) is used as an ingredient in a wide variety of coatings, resins, photosensitive materials, and superabsorbent baby diapers. We studied the effects of TMPTA on male and female rats and mice to identify potential toxic or cancer-related hazards.We applied solutions containing TMPTA in acetone on the backs of male and female rats and mice. Groups of 50 male and female rats and mice received 0.3, 1, or 3 milligrams of TMPTA per kilogram of body weight five days per week for two years. Groups of animals receiving acetone alone served as the control groups. At the end of the study, tissues from more than 40 sites were examined for every animal.Survival and body weights of all groups of exposed animals were similar to the control groups. Epidermal hyperplasia was observed in the skin at the site where the chemical was applied in all groups of animals receiving 1 mg/kg or more. Hyperkeratosis at the site of application was also increased in rats receiving TMPTA, and chronic inflammation was also seen in the skin of male and female mice receiving TMPTA. Malignant mesotheliomas were seen in a few male rats exposed to TMPTA. Two different rare forms of liver cancer (hepatoblastoma and hepatocholangiocarcinoma) were observed in some of the female mice exposed to TMPTA, and tumors of the uterus (stromal polyp or stromal sarcoma) also occurred in some exposed female mice.We conclude that exposure to TMPTA caused rare cancers of the liver and tumors of the uterus in female mice and may have been related to the occurrence of malignant mesothelioma in male rats. No occurrences of cancer were associated with exposure to TMPTA in female rats or male mice. Skin lesions at the site of application, including hyperplasia in rats and mice, hyperkeratosis in rats, and inflammation in mice occurred in all animal groups exposed to higher concentrations of TMPTA.

Objective: To assess procedures and outcomes in deliveries planned at home versus those planned in hospital among women choosing the place of delivery. Design: Follow up study of matched pairs. Setting: Antenatal clinics and reference hospitals in Zurich between 1989 and 1992. Subjects: 489 women opting for home delivery and 385 opting for hospital delivery; the women comprised all those attending members of the study team for antenatal care and those attending the reference hospital for antenatal care who could be matched with the women planning home confinement. Main outcome measures: Need for medication and incidence of interventions during delivery (caesarean section, forceps, vacuum extraction, episiotomy), duration of labour, occurrence of severe perineal lesions, maternal blood loss, and perinatal morbidity and death. Results: All women were followed up from their first antenatal visit till three months after delivery. Referrals during pregnancy (n = 37) and labour (70), changes of mind (15 home to hospital, eight hospital to home), and 17 miscarriages resulted in 369 births occurring at home and 486 in hospital. During delivery the home birth group needed significantly less medication and fewer interventions whereas no differences were found in durations of labour, occurrence of severe perineal lesions, and maternal blood loss. Perinatal death was recorded in one planned hospital delivery and one planned home delivery (overall perinatal mortality 2.3/1000). There was no difference between home and hospital delivered babies in birth weight, gestational age, or clinical condition. Apgar scores were slightly higher and umbilical cord pH lower in home births, but these differences may have been due to differences in clamping and the time of transportation. Conclusion: Healthy low risk women who wish to deliver at home have no increased risk either to themselves or to their babies. Key messages Interventions (induction, caesarean section, medication, forceps, or vacuum extraction) may be considerably less frequent in women who originally opt for home delivery There are no obvious disadvantages of home delivery for mother or child when the mother opts for home delivery More studies are needed to look into the small risks of death, serious bleeding, and complications of interventions, which could not be evaluated in this study owing to limited power

Tests for the induction of chromosomal aberrations (ABS) and micronuclei (MN) in bone marrow cells of mice have been conducted on 65 chemicals. Although these tests were not conducted with the purpose of comparing the outcomes of these two in vivo genetic toxicity endpoints, the availability of these test results permits such a comparison. Based on studies to date, results from the 2 tests agree for more than 80% of the chemicals; 17 gave positive results in both tests, and 36 gave negative results in both. Seven chemicals were positive only for ABS and 5 were positive only for MN. Three chemicals that were originally concluded to be positive for ABS but not for MN were found to induce MN when the MN protocol was modified to more closely reflect the ABS protocol. Among the 12 chemicals for which there are discrepant results, there are only 2 for which the difference is convincing. One of these, selenium sulfide (MN negative, ABS positive) remains an enigma; further studies are being conducted. The second, isoprene (MN positive, ABS negative) will be difficult to pursue because the studies reported here were done by inhalation exposure. Based on the outcomes of these comparisons, protocol factors, rather than endpoint specificity, appear to be the major source of discrepant test results. Thus, these results do not support a recommendation that both tests be conducted in a primary testing scheme for genetic toxicity.

The purpose of this study was to determine whether joint velocities and segmental angular velocities are significantly correlated with ball velocity during an instep soccer kick. We developed a deterministic model that related ball velocity to kicking leg and pelvis motion from the initiation of downswing until impact. Three-dimensional videography was used to collect data from 16 experienced male soccer players (age = 24.8 +/- 5.5 years; height = 1.80 +/- 0.07m; mass = 76.73 +/- 8.31 kg) while kicking a stationary soccer ball into a goal 12 m away with their right foot with maximal effort. We found that impact velocities of the foot center of mass (CM), the impact velocity of the foot CM relative to the knee, peak velocity of the knee relative to the hip, and the peak angular thigh velocity were significantly correlated with ball velocity. These data suggest that linear and angular velocities at and prior to impact are critical to developing high ball velocity. Since events prior to impact are critical for kick success, coordination and summation of speeds throughout the kicking motion are important factors. Segmental coordination that occurs during a maximal effort kick is critical for completing a successful kick.

Loss of muscle mass in microgravity is one of the primary factors limiting long-term space flight. NASA researchers have developed a number of exercise devices to address this problem. The most recent is the Advanced Resistive Exercise Device (ARED), which is currently used by astronauts on the International Space Station (ISS) to emulate typical free-weight exercises in microgravity. ARED exercise on the ISS is intended to reproduce Earth-level muscle loads, but the actual muscle loads produced remain unknown as they cannot currently be measured directly. In this study we estimated muscle loads experienced during squat exercise on ARED in microgravity conditions representative of Mars, the moon, and the ISS. The estimates were generated using a subject-specific musculoskeletal computer model and ARED exercise data collected on Earth. The results provide insight into the capabilities and limitations of the ARED machine.

Beta-myrcene, an acyclic unsubstituted monoterpene, and the essential oils which contain it are used as intermediates in the production of terpene alcohols (geraniol, nerol, and linalool), which, in turn, serve as intermediates in the production of aroma and flavor chemicals. Thus beta-myrcene is used widely in cosmetics, soaps, and detergents and as a flavoring additive in food and beverages. Beta-myrcene is also the major constituent of hop and bay oils, which are used in the manufacture of alcoholic beverages. Beta-myrcene was nominated for study by the National Institute of Environmental Health Sciences based on its high production volume, high level of human exposure, and structural relationship to d-limonene, which induced neoplasms in the kidneys of male rats in association with hyaline droplet nephropathy (NTP, 1990). Male and female F344/N rats and B6C3F1 mice were administered beta-myrcene (greater than 90% pure) by gavage for 3 months or 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Escherichia coli, and mouse peripheral blood erythrocytes. 3-MONTH STUDY IN RATS: Groups of 10 male and 10 female rats were administered 0, 0.25, 0.5, 1, 2, or 4 g beta-myrcene/kg body weight in corn oil by gavage, 5 days per week for 14 weeks. Additional groups of 10 male and 10 female special study rats were administered the same doses for 23 days. All core study rats in the 4 g/kg groups died during the first week of the study except one male that died on day 11. One to three rats in the 1 and 2 g/kg groups and one 0.5 g/kg male died by week 10 of the study. One 2 g/kg female died during the last week of the study. Except for lesion incidence data in groups administered 2 g/kg or less, data from rats that died early were excluded from the analysis and summary tables. Mean body weights were significantly decreased in male rats in the 0.5, 1, and 2 g/kg groups. Special study rats in the 4 g/kg groups died by the end of the first week. Dose-related clinical findings in animals that died early included thinness, lethargy, abnormal breathing, and ruffled fur. Right kidney and liver weights of dosed males and females were generally significantly greater than those of the vehicle controls. In special study rats evaluated on day 23, the incidences and severities of chronic progressive nephropathy (CPN) and renal tubule degeneration were increased in 2 g/kg males. At the end of the 3-month study, the incidences of renal tubule necrosis were significantly increased in all dosed groups of males and females. At 3 months, the incidences of olfactory epithelium degeneration in 2 g/kg males and females were significantly increased, and the severities were increased. The incidences of chronic inflammation in 1 and 2 g/kg males and females were significantly increased. All 2 g/kg males and females had splenic atrophy. In the mesenteric lymph node, significantly increased incidences of atrophy occurred in 2 g/kg males and 1 and 2 g/kg females. Acute inflammation of the forestomach occurred in four 2 g/kg females. The incidences of porphyrin pigmentation in the Harderian gland of males administered 0.5 g/kg or greater were significantly increased. 3-MONTH STUDY IN MICE: Groups of 10 male and 10 female mice were administered 0, 0.25, 0.5, 1, 2, or 4 g beta-myrcene/kg body weight in corn oil by gavage, 5 days per week for 14 weeks. All 4 g/kg male and female mice died during week 1; nine 2 g/kg males and eight 2 g/kg females died by week 4. The mean body weights of 1 g/kg males were significantly less than those of the vehicle controls. Clinical findings in animals that did not survive to the end of the study included thinness, lethargy, and abnormal breathing. The right kidney weights of 1 g/kg females and the liver weights of females administered 0.5 or 1 g/kg were significantly increased. No histopathology changes were observed in mice administered 1 g/kg or less. The 2 and 4 g/kg mice were not evaluated due to early deaths. 2-YEAR STUDY IN RATS: Groups of 50 male and 50 female rats were administered 0, 0.25, 0.5, or 1 g beta-myrcene/kg body weight in corn oil by gavage, 5 days per week for 105 weeks. All 1 g/kg male rats died before the end of the study due to renal toxicity. Compared to vehicle controls, the mean body weights of 0.25 and 0.5 g/kg males were slightly greater, and mean body weights of 1 g/kg males and females were at least 8% less than those of vehicle controls after 11 weeks and 13 weeks, respectively. In the standard evaluation of the kidney, the incidence of renal tubule adenoma was significantly increased in 0.5 g/kg male rats, and the combined incidences of renal tubule adenoma or carcinoma were significantly increased in 0.25 and 0.5 g/kg males. In both the extended evaluation and the combined standard and extended evaluations, the incidences of renal tubule adenoma and the combined incidences of renal tubule adenoma or carcinoma were significantly increased in the 0.25 and 0.5 g/kg groups of males. The incidences of renal tubule nephrosis (nephrosis) were markedly increased in all dosed groups of both sexes except in 0.25 g/kg females. The incidences of papillary mineralization in 0.25 and 0.5 g/kg males were significantly increased. Significantly increased incidences of nephropathy occurred in dosed females, and the severity was increased in the 0.5 and 1 g/kg males and females. The incidences of hyperplasia of the transitional epithelium lining the pelvis and overlying the renal papilla were significantly increased in all dosed groups of males and females. In male rats, the incidences of focal suppurative inflammation were significantly increased in the 0.25 and 0.5 g/kg groups. A significantly increased incidence of chronic active inflammation of the nose occurred in 0.5 g/kg males. Also in 0.5 g/kg males, the incidence of chronic active inflammation of the forestomach was increased. 2-YEAR STUDY IN MICE: Groups of 50 male and 50 female mice were administered 0, 0.25, 0.5, or 1 g beta-myrcene/kg body weight in corn oil by gavage, 5 days per week for 104 or 105 weeks. Survival of 1 g/kg mice was significantly less than that of the vehicle controls; the cause of the deaths was uncertain. Mean body weights of 1 g/kg males were at least 8% less than those of the vehicle controls between week 8 and week 56. Mean body weights of 0.5 g/kg females were at least 7% less than those of the vehicle controls after week 17, and those of 1 g/kg females were at least 8% less from week 11 to week 96. The incidences of liver neoplasms were significantly increased in 0.25 and/or 0.5 g/kg males and 0.25 g/kg females. Liver neoplasms included hepatocellular adenoma and hepatocellular carcinoma in males and females and hepatoblastoma in males. The incidences of hepatocellular hypertrophy were significantly increased in 0.5 g/kg males and females, as was the incidence of mixed cell focus in 0.5 g/kg females. The incidences of bone marrow atrophy and lymph node follicle atrophy in the spleen were significantly increased in 0.5 g/kg females. In the forestomach, there were significantly increased incidences of inflammation and epithelial hyperplasia in 0.5 g/kg females.beta-myrcene did not show evidence of genotoxicity in assays conducted by the NTP. No mutagenicity was observed in any of several strains of Salmonella typhimurium or Escherichia coli in two independent Ames assays conducted with and without exogenous metabolic activation. In addition, no significant increase in frequency of micronucleated normochromatic erythrocytes, biomarkers of chromosomal damage, was observed in male or female mice administered beta-myrcene for 3 months by gavage.Under the conditions of these 2-year gavage studies, there was clear evidence of carcinogenic activity of beta-myrcene in male F344/N rats based on increased incidences of renal tubule neoplasms. There was equivocal evidence of carcinogenic activity of beta-myrcene in female F344/N rats based on increased incidences of renal tubule adenoma. There was clear evidence of carcinogenic activity of beta-myrcene in male B6C3F1 mice based on increased incidences of hepatocellular adenoma, hepatocellular carcinoma, and hepatoblastoma. There was equivocal evidence of carcinogenic activity of beta-myrcene in female B6C3F1 mice based on marginally increased incidences of hepatocellular adenoma and carcinoma. Administration of beta-myrcene induced nonneoplastic lesions in the kidney of male and female rats, nose of male rats, and liver of male and female mice. Synonyms: 2-Methyl-6-methylene-2,7-octadiene; 7-methyl-3-methylene-1,6-octadiene; myrcene.

Bipedal walking is a typical activity of daily living, but the overarching control strategy used by the central nervous system (CNS) to make this motion efficient, or even possible, remains unknown. Researchers in robotics have developed control strategies for bipedal gait through the regulation of central (i.e., about the mass center) angular momentum resolved along three orthogonal directions during the walking cycle. Although recent research has focused on conservation of whole-body central angular momentum as a possible control law for walking [1–3], there is little data to support this theory for other motions such as running or marching. Even less data exist for how whole-body linear momentum varies during human locomotion.Copyright © 2010 by ASME

The purpose of this investigation was to determine the effect of different lifting cadences on the ground reaction force (GRF) during the squat exercise. Squats performed with greater acceleration will produce greater inertial forces; however, it is not well understood how different squat cadences affect GRF. The hypotheses were that faster squat cadences would result in greater peak GRF and that the contributions of the body and barbell, both of equivalent mass, to total system inertial force would not be different. Six experienced male subjects (31 +/- 4 years, 180 +/- 9 cm, 88.8 +/- 13.3 kg) performed 3 sets of 3 squats using 3 different cadences (fast cadence [FC] = 1-second descent/1-second ascent; medium cadence [MC] = 3-second descent/1-second ascent; and slow cadence [SC] = 4-second descent/2-second ascent) while lifting a barbell mass equal to their body mass. Ground reaction force and velocity sensor data were used to calculate inertial force contributions of both the body and barbell to total inertial force. Peak GRF were significantly higher in FC squats compared to MC (p = 0.0002) and SC (p = 0.0002). Ranges of GRF were also significantly higher in FC compared to MC (p0.05) and higher in MC compared to SC (p0.05). The inertial forces associated with the body were larger than those associated with the barbell, regardless of cadence. Faster squat cadences result in significantly greater peak GRF as a result of the inertia of the system. This study demonstrates that GRF was more dependent on descent cadence than on ascent cadence and that researchers should not use a single point on the body to approximate the location of the center of mass during squat exercise analysis.

Researchers collecting gait kinematic data during treadmill locomotion are often interested in determining the times of toe off and heel strike for each stride. In the absence of additional hardware, only position data collected with motion-capture equipment may be available. Others have published methods for using kinematic data for detecting overground gait events. However, during treadmill locomotion, especially running, overground methods may not possess sufficient accuracy. The purpose of this paper is to describe a method for using kinematic data to determine the time of toe off during treadmill locomotion. Ten subjects walked and ran on a treadmill while a motion-capture system collected positional data from heel and toe markers. The treadmill was equipped with force platforms that allowed an accurate determination of foot-ground contact. The time of toe off was determined using the vertical component of the toe marker, and this method was found to have greater accuracy for event detection than other published methods. Researchers can use the described method to determine times of heel strike and toe off during treadmill locomotion using only kinematic data.

The effect of test-cell pressure on the performance of two resistojets was investigated. Tests were conducted in a vacuum facility at pressures ranging from 4.3 x 10 ~5 to 5.4 x 10" 1 Torr for two resistojet configurations: a laboratory model and an engineering model for the Space Station. The tests showed that for each thruster there was a decline in performance, even after correcting for test-cell pressure, when tested in vacuum pressures above 10 3 Torr. Measurements were made of surface temperature, thrust, and exit-plane pitot pressure over the range of test-cell pressures. From these measurements, the decline in performance of the laboratory-model resistojet at higher cell pressures was attributed to heat losses as a result of convection. For the engineering-model resistojet, the decline in performance was found to be a combination of heat loss and an effect of cell pressure on the nozzle flow.

The treatment of traumatic anterior glenohumeral instability has been a topic of debate over the last couple of decades. However, a consensus exists regarding the necessity of an individualized treatment plan based on the type and degree of instability and the patient's functional demands. Various open and arthroscopic techniques are among the currently used surgical procedures. Open reconstruction of the capsulolabral complex had been considered the treatment of choice for many years, but the latest results for arthroscopic anterior shoulder stabilization demonstrate its increasing use. The current literature suggests that with the introduction of suture anchors, it is possible to mirror the principles of open anterior shoulder stabilization and thus combine the general advantages of arthroscopic surgery with a low recurrence rate.

SUMMARY The addition of inertia to exercising astronauts could increase ground reaction forces and potentially provide a greater health benefit. However,conflicting results have been reported regarding the adaptations to additional mass (inertia) without additional net weight (gravitational force) during locomotion. We examined the effect of increasing inertia while maintaining net gravitational force on vertical ground reaction forces and temporal kinematics during walking and running. Vertical ground reaction force was measured for 10 healthy adults (five male/five female) during walking (1.34 m s–1) and running (3.13 m s–1) using a force-measuring treadmill. Subjects completed locomotion at normal weight and mass and at 10, 20, 30 and 40% of added inertial force. The added gravitational force was relieved with overhead suspension, so that the net force between the subject and treadmill at rest remained equal to 100% body weight. Ground reaction forces were affected by the added inertial force, but not to the magnitude predicted by the increase in mass, suggesting that adaptations in motion occurred. Vertical ground reaction force production and adaptations in gait temporal kinematics were different between walking and running. Peak vertical impact forces and loading rates increased with increased inertia during walking, and decreased during running. As inertia increased, peak vertical propulsive forces decreased during walking and did not change during running. Stride time increased during walking and running,and contact time increased during running. The increased inertial forces were utilized independently from gravitational forces by the motor control system when determining coordination strategies.

Shoulder arthroplasty is becoming increasingly important in orthopaedic surgery. Continuous development of the implants means that the modern endoprostheses make it possible to recreate the original anatomy with a high degree of accuracy. This is of decisive importance in the long-term restoration of physiological patterns of movement and achievement of pain relief. The modern shoulder arthroplasties allow adjustment of the important parameters: ante-/retroversion, inclination and offset to fit the individual anatomy of the proximal humerus. Fixation is the most important factor for the glenoid component; reduced bone stock can make this difficult. Cemented components are still the gold standard. For young patients surface replacement arthroplasty can be a good alternative treatment for early stages of osteoarthritis. In cuff tear arthropathy reverse prostheses can be used. Reversing the anatomical relationship between glenoid and humerus leads to medialisation and lowering of the center of rotation, which in turn leads to increased tension on the deltoid muscle. Because of the high complication rate this operation should be performed only by experienced shoulder surgeons.

Die erste arthroskopische Untersuchung eines Kniegelenkpraparats wurde 1918 durch Professor Kenji Takagi in Japan vorgenommen. In den funfziger Jahren entwickelte Dr. Masaki Watanabe das erste funktionelle Arthroskop, das Watanabe Nummer 21. Seit den siebziger Jahren gab es die ersten Operationskurse in den USA, die diese neue Technik der Arthroskopie vermittelten. 1974 wurde die erste Vereinigung, die „International Arthroscopy Association“, gegrundet und in den fruhen achtziger Jahren das erste Journal, das sich der Arthroskopie widmete: Arthroscopy: The Journal of Arthroscopic and Related Surgery [9]. Seitdem hat sich die Arthroskopie als diagnostisches und therapeutisches Verfahren weit verbreitet.