The presence, densities and species distribution of atypical mycobacteria were assayed in samples from swimming-pools in semi-public areas (hotels, recreational parks and camping grounds) and from whirlpools (in sauna institutes, fitness clubs and recreational parks). Tap water used to supply these pools was also investigated. Mycobacteria were frequently detected in all types of samples, the numbers in whirlpools on the average being about ten times higher than those in swimming-pools and tap water. Mycobacterium gordonae was the predominant species in all samples. Special attention was given to the possible presence of opportunistic pathogenic mycobacteria. M. marinum was not detected in any of the samples; M. kansasii was recovered 3 times from whirlpools only. M. avium and the M. fortuitum-M. chelonei complex were found in both types of pool samples but in highest densities in whirlpools. Mycobacterial densities exhibited a significantly negative association with the concentration of hypochlorous acid-1.0 mg/l being required to assure low levels in the bathing water. There was also a negative association with redox potential but positive associations with total aerobic colony count at 37 degrees C, ammonium and total Kjeldahl nitrogen (in swimming-pools only). No association was found with temperature, potassium permanganate consumption, total coliforms, Pseudomonas aeruginosa or Staphylococcus aureus.
Electron-electron interactions in high-mobility conductors can give rise to transport signatures resembling those described by classical hydrodynamics. Using a nanoscale scanning magnetometer, we imaged a distinctive hydrodynamic transport pattern-stationary current vortices-in a monolayer graphene device at room temperature. By measuring devices with increasing characteristic size, we observed the disappearance of the current vortex and thus verified a prediction of the hydrodynamic model. We further observed that vortex flow is present for both hole- and electron-dominated transport regimes but disappears in the ambipolar regime. We attribute this effect to a reduction of the vorticity diffusion length near charge neutrality. Our work showcases the power of local imaging techniques for unveiling exotic mesoscopic transport phenomena.
In highly viscous electron systems such as high-quality graphene above liquid nitrogen temperature, a linear response to applied electric current becomes essentially nonlocal, which can give rise to a number of new and counterintuitive phenomena including negative nonlocal resistance and current whirlpools. It has also been shown that, although both effects originate from high electron viscosity, a negative voltage drop does not principally require current backflow. In this work, we study the role of geometry on viscous flow and show that confinement effects and relative positions of injector and collector contacts play a pivotal role in the occurrence of whirlpools. Certain geometries may exhibit backflow at arbitrarily small values of the electron viscosity, whereas others require a specific threshold value for whirlpools to emerge.
Pseudomonas aeruginosa was isolated from seven commercial and two residential whirlpools that were treated with halogens. None of the commercial whirlpools was constantly maintained at appropriate disinfection levels. Superchlorination or the draining, cleaning, disinfection, and refilling of whirlpools markedly reduced densities of P. aeruginosa in whirlpool water, but the bacterial populations were rapidly reestablished (less than 10(3) cells per ml) when disinfectant concentrations decreased below recommended levels (chlorine, 3.0 ppm [3.0 micrograms/ml]; bromine, 6.0 ppm). P. aeruginosa in the water was replenished from various sources, such as hoses used to fill the whirlpool and the biofilm in the filter and piping of the whirlpool systems. Daily monitoring and adjustment of chemical characteristics (regardless of bather load) were essential for controlling densities of P. aeruginosa.
We argue that the sea of virtual quark-antiquark pairs in a proton is polarized. Quantum chromodynamics allows a valence quark to emit a gluon which then produces pairs. If the parent quark in this process exhibits a ${(1\ensuremath{-}x)}^{3}$ behavior as $x\ensuremath{\rightarrow}1$ then the antiquark with helicity the same as the original quark will have a leading ${(1\ensuremath{-}x)}^{5}$ distribution. Implications for the counting rules and for polarized Drell-Yan annihilation are discussed.
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Abstract Two vertical pipes, placed on the axis of an open circular tank and fitted with trumpet entries of different shapes, were used in turn as overflows. Water was led into the tank in such a way that the stream approaching the trumpet under test possessed tangential velocity, which caused a vortex to appear in and above the trumpet. The relations between head and discharge were determined under various conditions of tangential supply. The formation of a vortex greatly reduced the discharge, the decrease being even more marked with the shallow than with the deep trumpet. At low heads, where the flow was controlled by the weir action of the trumpet crest, the discharge varied with the shape of the crest as well as with the irrotational constant c and the head, therefore (as with purely radial supply) it must be determined by experiment. At high heads with the trumpet flooded, the throat controlled the flow; within certain limits, the discharge was dependent chiefly upon c and the head measured with the throat as datum, and an approximate theory which ignores friction was verified. Two types of instability, ‘surging’ at low heads and ‘spluttering’ at high heads, were examined. Both were due to the collapse and subsequent re-formation of feeble vortices, which caused the discharge to vary with time in a periodic manner.
Folliculitis caused by Pseudomonas aeruginosa has been increasing due to the popularity of hot tubs, swimming pools, and whirlpools. The follicular pustules and inflammatory papules usually occur after an incubation period of two to four days and improve spontaneously in seven to ten days. Despite the discomforts of the condition, treatment is usually not necessary and may even prolong the infection. Since it is difficult to control the growth of Pseudomonas in hot tubs and whirlpools, attention to water conditions is the best way to prevent this irritating skin condition.
OBJECTIVE: To determine the efficacy of warm whirlpool, cold whirlpool, and contrast therapy in the treatment of delayed-onset muscle soreness. DESIGN AND SETTING: Subjects performed eccentric contractions of the elbow flexors and received 4 treatments: immediately postexercise and 24, 48, and 72 hours postexercise. Treatments consisted of 24-minute treatments with warm whirlpool, cold whirlpool, contrast therapy, or no treatment. SUBJECTS: Fifty-six sex-matched volunteers from the University of Pittsburgh. MEASUREMENTS: Measurements were taken at 5 assessment times: pre-exercise (0 hours); prior to treatment at 24, 48, and 72 hours postexercise; and at 96 hours postexercise. Dependent variables were degrees of resting elbow flexion, active elbow flexion, and extension; perceived soreness values on a Graphic Pain Rating Scale; and maximal voluntary isometric contraction. A repeated-measures analysis of variance (group by time) and Tukey post hoc analysis were used to determine which treatment groups differed significantly in returning subjects to pre-exercise values. RESULTS: Cold whirlpool and contrast therapy were found to return subjects to baseline values of resting elbow flexion and perceived soreness significantly more than warm whirlpool or no treatment (P < .01). Additionally, warm whirlpool was found to be more effective than no treatment in the return of resting elbow flexion (P < .01). CONCLUSIONS: These results suggest that cold whirlpool and contrast therapy are more effective than warm whirlpool or no treatment in alleviating delayed-onset muscle soreness in the elbow flexors.
Three previously healthy outpatients had urinary tract infection caused by Pseudomonas aeruginosa. Investigation disclosed that all three patients had been exposed to whirlpool baths within 48 hours before the onset of symptoms. Pseudomonas aeruginosa was isolated from the whirlpool bath associated with each case. Whirlpool baths and spas are commonly contaminated with Pseudomonas and have in the past been associated with rash illness and folliculitis. In addition to these skin infections, our results indicate that whirlpool bath or spa exposure may be an emerging risk factor associated with Pseudomonas urinary tract infections among outpatients.
The purpose was to determine if cold whirlpool treatment decreases functional performance equally regardless of gender. A secondary aim was to determine if there is a gradual increase in functional performance across time. Twenty-one college-aged subjects volunteered to participate in this study and were required to perform four measures of functional performance including: counter movement vertical jump, T-test, 36.58-meter dash (40-yard), and active range of motion of the ankle. Participants were treated with a 20 minute, 10 degree Celsius cold whirlpool following the pre-test of a given functional performance measure. Participants demonstrated significant decreases in counter movement vertical jump, T-test, and 40-yard dash performance immediately following treatment. Vertical jump performance remained impaired for at least 32 minutes. While both the T-test and 40-yard dash were affected for 7 and 22 minutes post- treatment, respectively. Participants also demonstrated significant decreases in peak power and average power immediately after and for 32 minutes post-treatment. Dorsiflexion was significantly decreased 7 and 12 minutes following treatment. There were no differences for plantar flexion, inversion, or eversion. These data suggest functional performance was affected immediately following and for up to 32 minutes after cold whirlpool treatment. It was also evident that there is a gradual performance increase for each measure of functional performance across time. Therefore, the consequences should be carefully considered before returning athletes to activity following cold whirlpool treatment. Key pointsCryotherapy is a common and highly effective modality in treating acute and chronic athletic injuries.The results indicated that cold whirlpool does have an immediate and subsequent effect on functional performance.Understanding how cold whirlpool adversely affects functional performance allows clinicians to continue using this modality before vigorous athletic activity.
An outbreak of folliculitis caused by Pseudomonas aeruginosa serotype O:7 occurred among the guests of a hotel in St. John's, Newfoundland, Canada, and the source of the infection was traced to the hotel whirlpool. Of 36 persons who used the whirlpool, 26 (72%) developed folliculitis within 1 to 5 days after exposure; the attack rate was significantly higher for children (90%) than for adults (50%). The rash characteristics were consistent with those of Pseudomonas folliculitis previously described (T. L. Gustafson, J. D. Band, R. H. Hutcheson, Jr., and W. Schaffner, Rev. Infect. Dis. 5:1-8, 1983). This is considered to be the first outbreak in which P. aeruginosa serotype O:7 has been incriminated. Published reports to date of outbreaks of Pseudomonas folliculitis associated with the use of whirlpools, hot tubs, swimming pools, etc., were reviewed.
Fourteen of 23 female members of a church group experienced an acute self-limited illness characterized by chills, fever, chest pain, cough, and nausea, consistent with the diagnosis of Pontiac fever. All 14 affected women had used a whirlpool located in the women's locker room during a racquetball party. Legionella pneumophila serogroup 6 was isolated from the women's whirlpool. Nine of 14 cases showed a seroconversion to heat-fixed antigen prepared from the L pneumophila serogroup 6 isolate. Aerosol size studies show that the whirlpool aerator produced water droplets small enough to travel deep into the tracheobronchial tree but large enough to transport L pneumophila. This outbreak demonstrated that Pontiac fever may be associated with L pneumophila serogroup 6, that whirlpools can serve as a reservoir for these organisms, and that seroconversion can occur in the absence of illness.
Three cases of an unusual Pseudomonas skin infection acquired from a health spa whirlpool were reported, and an epidemiologic survey showed 17 additional cases. This dermatosis is characterized by the abrupt onset of urticarial papules and superficial and deep papulopustules that spare only the head and neck and occur eight to 48 hours after using the whirlpool. Cultures from one patient's pustules and from the spa whirlpool environment were positive for P aeruginosa, serotype O-11. The condition cleared in all but one patient, without treatment, within seven to ten days. This patient continues to have recurrent follicular pustules three months after exposure. Samples from whirlpools at six other selected establishments were also positive for P aeruginosa.
Using data from the PdBI Arcsecond Whirlpool Survey (PAWS), we have generated the largest extragalactic giant molecular cloud (GMC) catalog to date, containing 1507 individual objects. GMCs in the inner M51 disk account for only 54% of the total 12 CO(1–0) luminosity of the survey, but on average they exhibit physical properties similar to Galactic GMCs. We do not find a strong correlation between the GMC size and velocity dispersion, and a simple virial analysis suggests that ∼30% of GMCs in M51 are unbound. We have analyzed the GMC properties within seven dynamically motivated galactic environments, finding that GMCs in the spiral arms and in the central region are brighter and have higher velocity dispersions than inter-arm clouds. Globally, the GMC mass distribution does not follow a simple power-law shape. Instead, we find that the shape of the mass distribution varies with galactic environment: the distribution is steeper in inter-arm region than in the spiral arms, and exhibits a sharp truncation at high masses for the nuclear bar region. We propose that the observed environmental variations in the GMC properties and mass distributions are a consequence of the combined action of large-scale dynamical processes and feedback from high-mass star formation. We describe some challenges of using existing GMC identification techniques for decomposing the 12 CO(1–0) emission in molecule-rich environments, such as M51's inner disk.
The Plateau de Bure Interferometer Arcsecond Whirlpool Survey has mapped the molecular gas in the central ∼9 kpc of M51 in its 12 CO(1–0) line emission at a cloud-scale resolution of ∼40 pc using both IRAM telescopes. We utilize this data set to quantitatively characterize the relation of molecular gas (or CO emission) to other tracers of the interstellar medium, star formation, and stellar populations of varying ages. Using two-dimensional maps, a polar cross-correlation technique and pixel-by-pixel diagrams, we find: (1) that (as expected) the distribution of the molecular gas can be linked to different components of the gravitational potential; (2) evidence for a physical link between CO line emission and radio continuum that seems not to be caused by massive stars, but rather depends on the gas density; (3) a close spatial relation between polycyclic aromatic hydrocarbon (PAH) and molecular gas emission, but no predictive power of PAH emission for the molecular gas mass; (4) that the I − H color map is an excellent predictor of the distribution (and to a lesser degree, the brightness) of CO emission; and (5) that the impact of massive (UV-intense) young star-forming regions on the bulk of the molecular gas in central ∼9 kpc cannot be significant due to a complex spatial relation between molecular gas and star-forming regions that ranges from cospatial to spatially offset to absent. The last point, in particular, highlights the importance of galactic environment—and thus the underlying gravitational potential—for the distribution of molecular gas and star formation.
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OBJECTIVE: To describe an additional maneuver during sonography for ovarian torsion and to assess its diagnostic value. METHODS: During a period of about 2 years 6 months, 21 patients with acute or intermittent lower abdominal pain who had an ovarian mass and an extraovarian mass suggestive of a twisted vascular pedicle on sonography were studied. The gray scale features of the ovarian mass were recorded. The presence of a twisted vascular pedicle was evaluated. Its location and gray scale features were noted. The probe was moved to and fro along the axis of the pedicle, and the presence of a whirlpool sign was evaluated. The same procedure was repeated on a color Doppler study. RESULTS: A twisted pedicle with a whirlpool sign was seen in all 21 patients. Ovarian torsion was confirmed in all 20 patients who underwent surgery. The last patient was pregnant and did well with conservative treatment. Hemorrhagic infarction or early hemorrhage of the ovary or ovarian mass was seen in all 8 patients who did not show flow in the twisted pedicle on the color Doppler study and in 2 patients who showed flow in the artery in the proximal part of the pedicle. Of the 6 patients who showed flow in the artery alone, the ovary was removed in 4, and all had hemorrhagic infarction or early hemorrhage. The ovary was viable in all 5 patients in whom flow was seen in both the artery and vein. CONCLUSIONS: A positive whirlpool sign in the twisted vascular pedicle of the ovary is the most definitive sign of ovarian torsion. Absence of blood flow in the twisted pedicle and visualization of the flow in the artery alone are predictive of nonviability of the ovary.
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