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This study aimed to characterize spatial/temporal variations of ambient volatile organic compounds (VOCs) using a community-scale monitoring approach and identify the main sources of concern in Paterson, NJ, an urban area with mixed sources of VOCs. VOC samples were simultaneously collected from three local source-dominated (i.e., commercial, industrial, and mobile) sites in Paterson and one background site in Chester, NJ (located ∼58 km southwest of Paterson). Samples were collected using the EPA TO-15 method from midnight to midnight, one in every sixth day over one year. Among the 60 analyzed VOCs, ten VOCs (acetylene, benzene, dichloromethane, ethylbenzene, methyl ethyl ketone, styrene, toluene, m,p-xylene, o-xylene, and p-dichlorobenzene) were selected to examine their spatial/temporal variations. All of the 10 VOCs in Paterson were significantly higher than the background site (p

This paper introduces a wireless pump that uses magnetic wireless manipulation to pump blood in the legs. A compact size and sufficient hydrodynamic performance were the most important requirements. Because the bonded magnet technique allows for a complex shape and various magnetization orientations, we fabricated a magnetic impeller from magnetic SmFeN powder. The impellers demonstrated a magnetic moment of 2772.64 emu and coercive force of 7.55 kOe. Using the impeller, we developed a tiny blood pump with a diameter of 22mm and height of 6mm. The pump allows for a maximum flow rate of 2.7 l/min and maximum pump head of approximately 170mm Hg at a rotating speed of 6000 rpm. This level of hydrodynamic performance is sufficient to circulate blood in the legs. In this paper, we present the magnetic properties of the magnetic impeller and the hydrodynamic performance with wireless operation. [ABSTRACT FROM AUTHOR]

Objective: In this paper, we investigated the parameters with effective traceability to assess the mechanical properties of interventional devices.Methods: In our evaluation system, a box-shaped poly (vinyl alcohol) hydrogel (PVA-H) and silicone were prepared with realistic geometry, and the measurement and evaluation of traceability were carried out on devices using load hand force. The phantom models had a total of five curve pathways to reach the aneurysm sac.Results: Traceability depends on the performance of the interventional devices in order to pass through the curved part of the model simulation track. The traceability of the guide wire was found to be much better than that of the balloon and stent loading catheter, as it reached the aneurysm sac in both phantom models.Conclusions: Observation using the video record is another advantage of our system, because the high transparency of the materials with silicone and PVA-H can allow visualization of the inside of an artery. [ABSTRACT FROM AUTHOR]

This study shows the improvement of muscle activity and muscle strength imbalance in the lower extremities through independent exercise loads in vibration platform. Twenty females of age 20 participated in this study. The subjects were divided into WBV group, with more than 10% of muscle strength imbalance between left and right the lower extremities, and control group, with less than 10% of muscle strength imbalance between left and right the lower extremities. As the prior experiment showed, different exercise postures provide different muscular activities. As a result, the highest muscular activity was found to be in the low squat posture. Therefore, the LS posture was selected for the exercise in this experiment. Vibration intensities were applied to dominant muscle and non-dominant muscle, and the vibration frequency was fixed at 25Hz for the WBV group. The control group was asked to perform the same exercise as the WBV group, without stimulated vibration. This exercise was conducted for a total of 4 weeks. As a result, the WBV group which showed an average deviation of 16% before the experiment, tended to decrease approximately to 5%. In this study, vibration exercise using load deviation is shown to be effective in improving the muscle strength imbalance. [ABSTRACT FROM AUTHOR]

This study was performed to assess the improvement of muscle strength imbalance in the lower limbs using a four point weight bearing reduction system with a two-belt treadmill. Participants, each having differences in muscle function of the left and right legs of over 20%, were divided into two groups of ten. The participants were involved in experiments progressing 40 minutes per day, 3 days per week, during a period of 4 weeks. The maximal peak torque and average power were measured for testing joint torque in the hip, knee and ankle. The results showed the improvement of muscle imbalance as assessed by the maximal muscle strength was the most effective in the hip joint, while the improvement of muscular reaction was the most effective in the knee joint. We suggest that the method of weight bearing reduction could be sufficient to reduce muscle imbalance in the lower limbs. [ABSTRACT FROM AUTHOR]

This research was performed to assess the effects of angled whole body vibration on muscle activity of the lower limbs, by examining adults in their twenties during squat exercises, taking into account two variables of exercise intensity (vibration frequency and gradient). Twenty healthy males in their twenties with previous experience of more than 6 month's weight training and no past medical history were included in this study. The experiment was performed by participating in squat exercises which consisted of 3 sets (1 set = 5 seconds x 3 repetitions of exercise), and the muscle activities of the Rectus Femoris, Vastus Lateralis, Vastus Medialis were measured with variation in the gradients of 0°, 10°, and 20°, and vibration frequencies of 20, 30, and 40 Hz. At 30 and 40 Hz, the vastus lateralis showed the highest change in muscle activity, while activity of the vastus medialis also increased significantly. Analysis of muscle activity according to the gradient showed a significant increase of the vastus lateralis at 20°, while the highest muscle activity at 20° was observed for the vastus medialis. In comparison of the change in lower limb muscle activity according to simultaneous stimulation, at a gradient of 10°, high activity was shown in muscle, while at 20°, high muscle activities were produced at 40 Hz in the vastus lateralis, 40 Hz in the rectus femoris, and both 30 and 40 Hz in the vastus medialis [ABSTRACT FROM AUTHOR]

In this study, we assessed indoor horse riding exercise's effects on basal physical exercise and activities of daily living (ADL) function using horse riding equipment, involving elderly test subjects (in their sixties). The participants were 20 people with no impediment to activity. They participated in experiments that lasted 60 min per day, 3 days per week, over 8 weeks, using the "SRider" (Rider Co. and Chonbuk National University Korea).We measured trunk flexion, sit-up, whole-body reaction, leg strength, and maximal oxygen uptake as basal physical fitness parameters. Also, 3-m gait, single stance with eyes open, and single stance with eyes closed, as ADL functions, were estimated once per month. The leg strength and whole body reaction result were significantly higher than before the exercise program. Moreover, the results of the 3-m walking ability alone increased significantly among the ADL functions. These findings indicate that the horse riding exercise may activate continuous muscular contraction, maintaining the tonus of the muscles. The continuous movement of horse riding could be lead to isometric muscle contraction in the lower limbs. These results suggest that the horse riding exercise develops muscle power and muscle reactions with exercise. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate muscle function and basal physical fitness in relation to muscle balance pattern using rowing machines. Twenty four subjects participated in this study, using three different rowing machines. Rowing exercises were performed for twenty-five times a set, four sets a day, 3 days a week, for 8 weeks. Biodex system 3(Biodex Medical Systems Co., New York, USA) was used to measure joint torques in the elbow, shoulder, lumbar and knee of subjects, for analyzing muscle function. The evaluation of basal physical fitness included body composition, muscle strength, muscle endurance, muscle reaction, agility, flexibility and explosive power. Before the experiment, significant differences of joint torques in the elbow, shoulder, lumbar and knee were present between subjects in the group. After the rowing exercise, significant improvement in every joint was witnessed. All aspects of basic fitness increased significantly, and the most improvement was observed in muscle strength from the joint torque results. As shown in the following results, every joint it was evident to have improved by more than 30% with the use of dependent load deviation type over the previously used water load method. This means that it is more effective for enhancing muscle strength and endurance to keep the muscle balance using dependent load deviation. The human body maintains motor coordination of muscle contraction during exercise. The muscle balances in the upper-lower and left-right arms could assist with effective activation of motor coordination. In this paper, an exercise method using dependent load deviation was demonstrated to be more efficient for improving muscle imbalance and strengthening muscles. [ABSTRACT FROM AUTHOR]

The effect of stent design parameters such as porosity, pore density, number of strands, and strut angle to the artery were studied in vitro using particle image velocimetry (PIV). Five mesh stents were implanted into a sidewall aneurysm model. The flow features in a sidewall aneurysm silicone phantom model were investigated at a Reynolds number of 300. It was found that the lowest porosity stent had the best value for velocity and vorticity reduction in an aneurysm pocket. The stent with higher pore density had a tendency to decrease the mean and maximum velocities, but it was not superior to the effects of porosity. In addition, investigation of the evaluation system confirmed that higher stent strut angles to the parent artery had a tendency to lower mean velocity, as shown by PIV and CFD. However, this effect was relatively smaller compared to porosity and pore density. Our evaluation system suggested the best combinations of parameters for the development of an ideal stent would be lower porosity, higher pore density, and higher strut angle. The results obtained in this study indicated that our evaluation system could be useful for various purposes related to evaluation of endovascular interventional devices. [ABSTRACT FROM AUTHOR]

The aim of this study is to verify the effect of indoor horse riding exercise on basal physical exercise and lumbar muscular function. The subjects included were 20 healthy females, who participated in the horse riding exercise using SRider (Rider Co. & ChonbuK National Univ, Korea) for 30 minutes per day, 3 days per week, over a period of 8 weeks. The subjects were divided into 4 groups as follows, with 10 subjects in each group: Postural Balance Exercise mode (PBE), Abdomen Exercise mode (ADE), Whole body Exercise mode (WBE), and Multiple Exercise (MTE). Isokinetic muscular function test was performed before and after the horse riding exercise, to assess the effect of horse riding on basal physical exercise and lumbar muscular function. The test result on basal physical exercise and isokinetic muscular function showed improvements with variable degree in the back muscle strength, maximum joint torque, total work, and muscular acceleration time. The result signifies that the horse riding is an antagonistic exercise mainly performed on waist and abdomen area, and the machine induces persistent muscle contraction and causes myotonic induction enhancing the muscle strength. Indoor horse riding exercise proved its effectiveness for senior or the disabled people who need muscle exercises but have difficulties performing outdoor activities. [ABSTRACT FROM AUTHOR]

This study investigated the characteristics of dynamic postural responses when subjects attempted to maintain an upright standing position on a support plate during continuous sinusoidal perturbation in the anterior-posterior direction. Fifteen healthy young subjects participated in the experiment. Body movement patterns during the perturbation were captured and analyzed using a 3D motion analysis system (APAS 3D motion analysis, Ariel Dynamics Inc.). Seven markers were attached on the subject's body to measure and analyze the motion patterns. The markers were positioned at the head, chest, hip, right knee, left knee, right ankle, and left ankle. Five different frequencies of motion were applied to the support surface: 0.1, 0.5, 1.0, 1.5, and 2.0 Hz with a 4-cm path of motion at the base. The experiments measured dynamic postural responses in a condition were subjects had their eyes open. The results showed that the median frequency of the knee and ankle increased in all frequency bands. Following an increase in the frequency of the perturbation, the postural control strategy was changed from the ankle strategy to a combined strategy. These experimental results could be applied to the dynamic postural training for the elderly and to rehabilitation training for patients to improve their ability for postural control. [ABSTRACT FROM AUTHOR]

Airborne hexavalent chromium (Cr(VI)) is a known pulmonary carcinogen and can be emitted from both natural and anthropogenic sources, including diesel emissions. However, there is limited knowledge about ambient Cr(VI) concentration levels and its particle size distribution. This pilot study characterized ambient Cr(VI) concentrations in the New Jersey Meadowlands (NJ ML) district, which is close to the heavily trafficked New Jersey Turnpike (NJTPK) as well as Chromium Ore Processing Residue (COPR) waste sites. Monitoring was simultaneously conducted at two sites, William site (~50 m from NJTPK) and MERI site (~700 m from NJTPK). The distance between the two sites is approximately 6.2 km. Ambient Cr(VI) concentrations and PM2.5 mass concentrations were concurrently measured at both sites during summer and winter. The summer concentrations (mean ± S.D. [median]), 0.13 ± 0.06 [0.12] ng/m³ at the MERI site and 0.08 ± 0.05 [0.07] ng/m³ at the William site, were all significantly higher than the winter concentrations, 0.02 ± 0.01 [0.02] ng/m³ and 0.03 ± 0.01 [0.03] ng/m³ at the MERI and William sites, respectively. The site difference (i.e., MERI > William) was observed for summer Cr(VI) concentrations; however, no differences for winter and pooled datasets. These results suggest higher Cr(VI) concentrations may be attributed from stronger atmospheric reactions such as photo-oxidation of Cr(III) to Cr(VI) in the summer. The Cr(VI) distribution as a function of particle size, ranging from 0.18 to 18 µm, was determined at the William site. It was found that Cr(VI) was enriched in the particles less than 2.5 µm in diameter (PM2.5). This finding suggested potential health concerns, because PM2.5 are easily inhaled and deposited in the alveoli. A multiple linear regression analysis confirmed ambient Cr(VI) concentrations were significantly affected by meteorological factors (i.e., temperature and humidity) and reactive gases/particles (i.e., O3, Fe and Mn). [ABSTRACT FROM AUTHOR]

The article discusses the spatial/temporal variations of particulate matter in Paterson, New Jersey, which is a mixed land-use community with industrial, commercial and residential lands. Three monitoring sites was chosen within the community and from November 18, 2005 - December 20, 2006, field sampling was done. The sampling revealed that there was a higher concentration of particulate matter in Pasterson compared to Chester due to presence of air pollutants in the area.

Dry steam cleaning, which has gained recent attention as an effective method to reduce house dust mite (HDM) allergen concentration and loading in carpets, was evaluated in this study for its efficacy in lowering levels of polycyclic aromatic hydrocarbons (PAHs) as well as HDM allergens. Fifty urban homes with wall-to-wall carpets, mostly low-income and with known lead contamination, were studied in 2003 and 2004. Two carpet-cleaning interventions were compared: Repeated HEPA (High Efficiency Particulate Air filtered) vacuuming alone and repeated HEPA vacuuming supplemented with dry steam cleaning. Vacuum samples were collected to measure carpet loading of dust and contaminants immediately before and after cleaning. Paired comparisons were conducted to evaluate the effectiveness of the cleaning protocols in reducing the levels of PAHs and HDM allergens in carpets. The results indicated that both cleaning methods substantially reduced the loading of PAHs and HDM allergens as well as dust in carpets (p< 0.0001). The reductions in loading of dust (64.4%), PAHs (69.1%), and HDM allergens (85.5%), by dry steam cleaning plus repetitive HEPA vacuuming were larger than the reductions by regular HEPA vacuuming alone: dust (55.5%), PAHs (58.6%), and HDM allergens (80.8%), although the difference was statistically significant only for dust and PAHs. We conclude that intensive HEPA vacuum cleaning substantially reduced the loading of PAHs and HDM allergens in carpets in these urban homes and that dry steam cleaning added modestly to cleaning effectiveness. [ABSTRACT FROM AUTHOR]

Accurate measurement of nitrogen dioxide concentrations in both outdoor and indoor environments, including personal exposures, is a fundamental step for linking atmospheric nitrogen dioxide levels to potential health and ecological effects. The measurement has been conducted generally in two ways: active (pumped) sampling and passive (diffusive) sampling. Diffusion samplers, initially developed and used for workplace air monitoring, have been found to be useful and cost-effective alternatives to conventional pumped samplers for monitoring ambient, indoor and personal exposures at the lower concentrations found in environmental settings. Since the 1970s, passive samplers have been deployed for ambient air monitoring in urban and rural sites, and to determine personal and indoor exposure to NO2. This article reviews the development of NO2 passive samplers, the sampling characteristics of passive samplers currently available, and their application in ambient and indoor air monitoring and personal exposure studies. The limitations and advantages of the various passive sampler geometries (i.e., tube, badge, and radial type) are also discussed. This review provides researchers and risk assessors with practical information about NO2 passive samplers, especially useful when designing field sampling strategies for exposure and indoor/outdoor air sampling.Journal of Exposure Science and Environmental Epidemiology (2008) 18, 441–451; doi:10.1038/jes.2008.22; published online 30 April 2008 [ABSTRACT FROM AUTHOR]

The soldering reaction and interracial microstructure formed between liquid Sn-Zn-Ag solder and Cu at the early stage of soldering at 250°C for 15 s were studied primarily with the aid of transmission electron microscope (TEM). To achieve the early stage reaction information, the soldered specimens, 5 mm x 5 mm x 500 µm solder on 10 mm x 10 mm x 20 µm Cu, were rapidly quenched in liquid nitrogen after soldering. The results of TEM interfacial analysis show that a Cu-Zn reaction zone, consisting of β′-CuZn and γ-Cu5Zn8, formed near Cu while a Ag-Zn zone, consisting of γ-Ag5Zn8 and ∈-AgZn3, formed near solder. The innermost layer adjacent to the Cu substrate is an amorphous Cu-Zn diffusion region that contains dispersed β′-CuZn nanocrystalline cells. The β′-CuZn also precipitates in the γ- Ag5Zn8 and ∈-AgZn3 layer due to the supersaturation of Cu. [ABSTRACT FROM AUTHOR]

The early dissolution behavior of Cu in a molten Sn-Zn-Ag solder was studied at 250 °C by fast quenching the dissolving specimen in liquid nitrogen. The atomic level dissolution behavior of Cu in the molten solder was revealed by high-resolution transmission electron microscopy. The dissolution of Cu occurs through channel dissolution and thermal vibrational dissolution. The dissolution channel has a dimension of less than 0.5 nm. The formation of channels, and thus the channel zone, is initiated by preferential removal of Cu atoms from the surface vacant site of Cu lattice. Relict strips of lattice between channels subsequently dissolve into the molten solder with the aid of thermal vibration and the interaction with liquid Zn atoms. The dissolved atoms form an atomic cluster zone. These clusters are the intermediate state of the dissolution of Cu from the channel zone into the molten Sn-Zn-Ag solder. The clusters convert into an amorphous structure prior to further formation of compound. [ABSTRACT FROM AUTHOR]

A short time reflow of 15 s at 250 °C, followed by a liquid nitrogen quench, of the Sn–3Ag–0.5Cu solder on a Cu substrate gave rise to a three-layer interfacial structure. In addition to the commonly known η-Cu6Sn5/[variant_greek_epsilon]-Cu3Sn layers, an amorphous layer with a thickness of less than 50 nm exists between the Cu substrate and the thin [variant_greek_epsilon]-Cu3Sn layer. Nanocrystalline [variant_greek_epsilon]-Cu3Sn cells, revealed by transmission electron microscopy (TEM), as fine as 10 nm were detected within the amorphous region. The results of TEM analysis suggest that the nucleation of interfacial intermetallic compound [variant_greek_epsilon]-Cu3Sn occurs within the amorphous layer. [ABSTRACT FROM AUTHOR]

A response to a letter to the editor is presented regarding an article about the pathological mechanism of the hot bath-related headache (HBRH).