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2.
Phys Rev Lett ; 119(17): 175702, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29219452

RESUMO

Nanosecond in situ x-ray diffraction and simultaneous velocimetry measurements were used to determine the crystal structure and pressure, respectively, of ramp-compressed aluminum at stress states between 111 and 475 GPa. The solid-solid Al phase transformations, fcc-hcp and hcp-bcc, are observed at 216±9 and 321±12 GPa, respectively, with the bcc phase persisting to 475 GPa. The high-pressure crystallographic texture of the hcp and bcc phases suggests close-packed or nearly close-packed lattice planes remain parallel through both transformations.

3.
Science ; 290(5500): 2285-7, 2000 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-11125137

RESUMO

Quantifying the moisture history of the Amazon Basin is essential for understanding the cause of rain forest diversity and its potential as a methane source. We reconstructed the Amazon River outflow history for the past 14,000 years to provide a moisture budget for the river drainage basin. The oxygen isotopic composition of planktonic foraminifera recovered from a marine sediment core in a region of Amazon River discharge shows that the Amazon Basin was extremely dry during the Younger Dryas, with the discharge reduced by at least 40% as compared with that of today. After the Younger Dryas, a meltwater-driven discharge event was followed by a steady increase in the Amazon Basin effective moisture throughout the Holocene.


Assuntos
Clima , Eucariotos/química , Água Doce , Sedimentos Geológicos , Isótopos de Oxigênio/análise , Zooplâncton/química , Animais , Oceano Atlântico , Brasil , Metano , Água do Mar , Temperatura , Fatores de Tempo
4.
Am J Infect Control ; 10(2): 60-5, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-6919398

RESUMO

Postoperative wound infections were evaluated in 1271 patients who had 1389 surgical procedures. There were 49 postoperative wound infections identified, of which 26 (53%) were discovered after discharge. Wound infections varied from 2.5% for clean wounds up to 13.3% for dirty wounds. Among the specialties, the infection rate ranged from no infection for otolaryngologists and urologists to 8.6% for general surgeons. With routine hospital surveillance, the overall infection rate was 1.8% or 2.2%, including readmissions for infection, but less than the actual rate of 3.8%. Persons who had three procedures had no infection rate of 27.3%; for two procedures, 8.1%; and for one procedure, 3.2%. Most postoperative wound infections detected after discharge were based on clinical grounds and not positive cultures. Rehospitalization was required for seven patients because of infection. This study demonstrates that postoperative wound infection surveillance must be continued after discharge.


Assuntos
Hospitais Comunitários , Infecção da Ferida Cirúrgica/epidemiologia , Arizona , Infecção Hospitalar/complicações , Infecção Hospitalar/epidemiologia , Humanos , Alta do Paciente , Infecção da Ferida Cirúrgica/etiologia , Fatores de Tempo
5.
Eur J Pharmacol ; 340(2-3): 221-5, 1997 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-9537819

RESUMO

Hypothalamic neuropeptide Y containing neurones are overactive and may mediate hyperphagia in insulin-deficient diabetic rats, but the factors stimulating them remain uncertain. To determine the possible role of glucocorticoids, we investigated the effects of the glucocorticoid receptor blocker mifepristone (RU486) on food intake and regional hypothalamic neuropeptide Y concentrations in streptozotocin-diabetic rats. RU486 (30 mg/kg) or corn oil vehicle control was given orally for 3 weeks to diabetic rats. Food intake and neuropeptide Y levels in the hypothalamic arcuate and paraventricular nuclei were increased in untreated diabetic rat groups (P < 0.01), and though RU486 did increase plasma corticosterone levels (P < 0.01) it did not have any effect on either feeding or neuropeptide Y levels (P = NS). These negative findings suggest that glucocorticoids may not be responsible for increasing hypothalamic neuropeptide Y or for hyperphagia in insulin-deficient diabetes.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Antagonistas de Hormônios/farmacologia , Hiperfagia/etiologia , Hipotálamo/metabolismo , Mifepristona/farmacologia , Neuropeptídeo Y/metabolismo , Receptores de Glucocorticoides/antagonistas & inibidores , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/psicologia , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Insulina/sangue , Masculino , Ratos , Ratos Wistar
6.
Altern Ther Health Med ; 7(1): 48-56, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11191042

RESUMO

CONTEXT: Since the mid-1980s, music therapy has been a regular feature of the residential program at the internationally renowned Bristol Cancer Help Centre, United Kingdom. Music therapy complements other therapeutic interventions available to residents at the center. OBJECTIVE: To compare the therapeutic effects of listening to music in a relaxed state with the active involvement of music improvisation (the playing of tuned and untuned percussion instruments) in a music therapy group setting and to investigate the potential influence of music therapy on positive emotions and the immune system of cancer patients. DESIGN: A quantitative pre-posttest, psychological/physiological measures, and qualitative focus group design. SETTING: A cancer help center that offers a fully integrated range of complementary therapies, psychological support, spiritual healing, and nutritional and self-help techniques addressing the physical, mental, emotional, and spiritual needs of cancer patients and their supporters. PARTICIPANTS: Twenty-nine cancer patients, aged 21 to 68 years. INTERVENTION: Group music therapy interventions of listening to recorded/live music in a relaxed state and improvisation. MAIN OUTCOME MEASURES: Increased well-being and relaxation and less tension during the listening experience. Increased well-being and energy and less tension during improvisation. Increased levels of salivary immunoglobulin A and decreased levels of cortisol in both experiences. RESULTS: Psychological data showed increased well-being and relaxation as well as altered energy levels in both interventions. Physiological data showed increased salivary immunoglobulin A in the listening experience and a decrease in cortisol levels in both interventions over a 2-day period. Preliminary evidence of a link between positive emotions and the immune system of cancer patients was found. CONCLUSIONS: These findings, which link listening to music in a relaxed state and improvisation to alterations in psychological and physiological parameters, may provide a better understanding of the effectiveness of music therapy for cancer patients.


Assuntos
Ansiedade/terapia , Musicoterapia , Neoplasias , Adulto , Idoso , Feminino , Grupos Focais , Humanos , Hidrocortisona/sangue , Imunoglobulinas/metabolismo , Masculino , Pessoa de Meia-Idade , Neoplasias/psicologia , Neoplasias/terapia , Projetos Piloto , Instituições Residenciais
7.
J Pediatr Ophthalmol Strabismus ; 38(3): 163-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11386649

RESUMO

PURPOSE: To establish the optimum timing of follow-up after probing for uncomplicated congenital nasolacrimal duct obstruction. METHODS: A retrospective review of notes of all patients probed over a 4-year period was performed. Timing of symptom resolution was evaluated and compared to the results of a questionnaire sent to all parents in June 1996. RESULTS: Most patients were asymptomatic or improved by 3 months postoperatively, and the long-term success rate was 96.6%. CONCLUSION: Optimum timing of follow-up should be 3 months postoperatively, if necessary at all.


Assuntos
Dacriocistorinostomia , Ducto Nasolacrimal/cirurgia , Seguimentos , Humanos , Lactente , Obstrução dos Ductos Lacrimais/congênito , Estudos Retrospectivos , Fatores de Tempo
8.
Orthopedics ; 7(6): 1002-4, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24823158

RESUMO

Ganglion cysts are a common entity arising around joints and tendon sheaths. We present a previously unreported location for a ganglion and review the various theories on etiology, pathogenesis, and treatment. With yet another unusual location for ganglia, over the acromioclavicular joint, we propose ganglia should be considered in the differential diagnosis of masses arising near any synovial joint or tendon sheath.

11.
Orbit ; 25(3): 253-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16987776

RESUMO

PURPOSE: To present a small case series of orbital implant exposures treated with porcine dermal collagen (Permacol, Tissue Science Laboratories PLC, Aldershot, Hants, UK) patching. METHODS: A retrospective chart review of three cases of orbital implant exposure treated with Permacol patching. RESULTS: Three cases were identified. There were 4 operative episodes of Permacol patching (one socket had two attempts at permacol patching). In all 4 cases the patch rapidly failed and melted away leaving behind the orbital implant exposure. All 3 patients required implant removal. CONCLUSIONS: Orbital implant exposure remains a major long-term complication of evisceration and enucleation procedures. On the basis of our experience, we would not recommend using Permacol as a non-autologous material for covering exposed Medpor (Medpor, Porex Surgical, Atlanta, Georgia, USA) orbital implants. Further study is required to fully assess the safety and efficacy profile of Permacol in socket surgery.


Assuntos
Colágeno , Órbita/cirurgia , Polietilenos , Próteses e Implantes , Adulto , Idoso , Feminino , Humanos , Masculino , Estudos Retrospectivos , Transplante Heterólogo
12.
J Reprod Fertil Suppl ; (23): 435-9, 1975 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1060821

RESUMO

Plasma progestagens were measured in eighteen pregnant mares to establish normal levels in the first and last 90 days of gestation. Progestagens increased from 25 ng/ml at 90 days before birth to 60 ng/ml at 10 days before birth, decreased to 58 ng/ml at 5 days before, and were 3 ng/ml or less by 5 days after perturition. During the first 90 days of pregnancy, progestagens reflected luteal activity with an increase in plasma levels from Day 30 to Day 60.


Assuntos
Cavalos/sangue , Prenhez , Progestinas/sangue , Animais , Feminino , Ovulação , Período Pós-Parto , Gravidez , Fatores de Tempo
13.
J Reprod Fertil Suppl ; (27): 245-50, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-289796

RESUMO

This study was undertaken to determine if fertility could be improved by increasing the interval from foaling to breeding. Forty-two mares, not bred during normal post-partum oestrus, were injected with a prostaglandin analogue on Day 6 or 7 following ovulation. Mares were mated artifically with antibiotic-treated semen during the resulting oestrus and, if necessary, for the following 4 cycles. Their fertility was compared, by cycles/pregnancy and rate of fetal loss, to mares bred by the same methods on 86 normal post-partum oestrous periods. The interval from foaling to the onset of breeding and the duration of oestrus were longer in the injected mares than the intervals observed in the untreated mares. Both groups averaged 1.3 breeding periods/pregnancy. The rate of fetal loss was not significantly different between the groups. Increasing the interval from foaling to breeding did not improve fertility.


Assuntos
Estro/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Cavalos/fisiologia , Prostaglandinas Sintéticas/farmacologia , Animais , Corpo Lúteo/efeitos dos fármacos , Feminino , Luteólise , Ovulação/efeitos dos fármacos , Gravidez
14.
J Reprod Fertil Suppl ; 32: 35-40, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6962871

RESUMO

Sterile filtrates were prepared from equine isolates of Klebsiella pneumoniae (genitalium), Proteus mirabilis, Pseudomonas aeruginosa, Escherichia coli, Streptococcus zooepidemicus, Streptococcus equisimilis, Actinobacillus equuli, and Corynebacterium equi and mixed individually with extended stallion semen. When diluted in the extended semen the filtrates represented bacterial populations of 0.5 x 10(6), 1 x 10(6), 2 x 10(6) and 4 x 10(6) cells/ml. pH values were recorded for each filtrate. Specimens were monitored for percentage motile spermatozoa at 30-min intervals until they reached 10% or less for 2 consecutive observations. All specimens were maintained at 25 degrees C in a water bath. Ten specimens were examined from each of 5 clinically normal stallions. The major reduction in percentage motile spermatozoa as compared to the control sample occurred before the first observation. From this point the rate of deterioration in motility in the filtrates approximated that of the control. The differences detected between the filtrates and control in percentage motile sperm cells were all statistically significant at P less than 0.01.


Assuntos
Fenômenos Fisiológicos Bacterianos , Cavalos/fisiologia , Sêmen/microbiologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Animais , Masculino , Especificidade da Espécie , Espermatozoides/microbiologia
15.
J Reprod Fertil Suppl ; (23): 139-42, 1975 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1107540

RESUMO

Sterile equipment was used to collect ten ejaculates from each of ten normal stallions and quantitative and qualitative bacterial counts were made within 15 min after collection. The mean bacterial population in undiluted semen was found to be 573,000 +/- 374,000 organisms/ml. The bacterial content of semen diluted with two parts sterile physiological saline, or with two parts of a cream-gelatin extender, was measured within 15 min after collection and again after 2 hr at 25 degrees C. The number of bacteria was slightly increased in the saline after 2 hr, but 1 93% and 99% reduction occurred in the extended semen within 15 min and after 2 hr at room temperature.


Assuntos
Cavalos , Sêmen/microbiologia , Animais , Técnicas Bacteriológicas , Enterobacter/isolamento & purificação , Escherichia coli/isolamento & purificação , Técnicas de Diluição do Indicador , Klebsiella/isolamento & purificação , Masculino , Proteus/isolamento & purificação , Pseudomonas/isolamento & purificação , Staphylococcus/isolamento & purificação , Streptococcus/isolamento & purificação
16.
Appl Opt ; 32(21): 3925-9, 1993 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-20830028

RESUMO

The high laser damage thresholds often reported for porous thin films are discussed in terms of point defects or small absorbing inclusions as sites of thin-film damage initiation. The model is based on the internal pressure built up upon laser heating at short times. The competing effects of short pressure relaxation distances and low thermal conductivity inherent in porous films are discussed. The model predicts that at thicknesses less than or equal to the neck or column diameter of a porous film, the effect of lower thermal conductivity should dominate and cause the films to exhibit lower laser damage thresholds than their denser counterparts.

17.
J Acoust Soc Am ; 94(2 Pt 1): 652-61, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8370871

RESUMO

Semiconductor strain gauges were used to measure the internal strain along the axes of spherical and disk plaster specimens when subjected to lithotripter shock pulses. The pulses were produced by one of two lithotripters. The first source generates spherically diverging shock waves of peak pressure approximately 1 MPa at the surface of the specimen. For this source, the incident and first reflected pressure (P) waves in both sphere and disk specimens were identified. In addition, waves reflected by the disk circumference were found to contribute significantly to the strain fields along the disk axis. Experimental results compared favorably to a ray theory analysis of a spherically diverging shock wave striking either concretion. For the sphere, pressure contours for the incident P wave and caustic lines were determined theoretically for an incident spherical shock wave. These caustic lines indicate the location of the highest stresses within the sphere and therefore the areas where damage may occur. Results were also presented for a second source that uses an ellipsoidal reflector to generate a 30-MPa focused shock wave, more closely approximating the wave fields of a clinical extracorporeal lithotripter.


Assuntos
Litotripsia , Semicondutores , Acústica , Modelos Teóricos
18.
Opt Lett ; 24(8): 516-8, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18071557

RESUMO

The 351-nm laser-damage initiation threshold for surface damage in conventionally polished fused silica is demonstrated to be stress dependent. By circumferential application of modest loads to a sample, a controllable stress field can be established within the clear aperture of a fused-silica specimen, in response to which both the damage-initiation fluence and the crack-propagation fluence requirements are increased above those for unstressed conditions.

19.
Appl Opt ; 38(33): 6892-903, 1999 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-18324232

RESUMO

Results of experiments on stress-inhibited laser-driven crack growth and stress-delayed laser-damage initiation thresholds in fused silica, borosilicate glass (BK-7), and cleaved bulk silica are presented. A numerical model is developed to explain the crack arrest in fused silica. Good agreement is obtained between the model and a finite-element code. The crack arrest is demonstrated to be the result of the breaking of a hoop-stress symmetry that is responsible for crack propagation in fused silica.

20.
Nature ; 411(6835): 290-3, 2001 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-11357127

RESUMO

Variations in the amount of solar radiation reaching the Earth are thought to influence climate, but the extent of this influence on timescales of millennia to decades is unclear. A number of climate records show correlations between solar cycles and climate, but the absolute changes in solar intensity over the range of decades to millennia are small and the influence of solar flux on climate is not well established. The formation of stalagmites in northern Oman has recorded past northward shifts of the intertropical convergence zone, whose northward migration stops near the southern shoreline of Arabia in the present climate. Here we present a high-resolution record of oxygen isotope variations, for the period from 9.6 to 6.1 kyr before present, in a Th-U-dated stalagmite from Oman. The delta18O record from the stalagmite, which serves as a proxy for variations in the tropical circulation and monsoon rainfall, allows us to make a direct comparison of the delta18O record with the Delta14C record from tree rings, which largely reflects changes in solar activity. The excellent correlation between the two records suggests that one of the primary controls on centennial- to decadal-scale changes in tropical rainfall and monsoon intensity during this time are variations in solar radiation.

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