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The prediction of a supersonic solar wind1 was first confirmed by spacecraft near Earth2,3 and later by spacecraft at heliocentric distances as small as 62 solar radii4. These missions showed that plasma accelerates as it emerges from the corona, aided by unidentified processes that transport energy outwards from the Sun before depositing it in the wind. Alfvénic fluctuations are a promising candidate for such a process because they are seen in the corona and solar wind and contain considerable energy5-7. Magnetic tension forces the corona to co-rotate with the Sun, but any residual rotation far from the Sun reported until now has been much smaller than the amplitude of waves and deflections from interacting wind streams8. Here we report observations of solar-wind plasma at heliocentric distances of about 35 solar radii9-11, well within the distance at which stream interactions become important. We find that Alfvén waves organize into structured velocity spikes with duration of up to minutes, which are associated with propagating S-like bends in the magnetic-field lines. We detect an increasing rotational component to the flow velocity of the solar wind around the Sun, peaking at 35 to 50 kilometres per second-considerably above the amplitude of the waves. These flows exceed classical velocity predictions of a few kilometres per second, challenging models of circulation in the corona and calling into question our understanding of how stars lose angular momentum and spin down as they age12-14.
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BACKGROUND: Retrospective studies of childhood peanut allergy demonstrate serum-specific IgE (IgE) levels against the peanut allergen Ara h2 may help predict a clinical reaction at food challenge. Fraction of exhaled nitric oxide (FeNO) is a non-invasive tool correlating to allergic airways inflammation and has been independently associated with increased food-specific IgE. OBJECTIVE: To assess the validity of serum-specific Ara h2 IgE measured prospectively to diagnose peanut allergy and explore the utility of FeNO as a non-invasive screening tool for childhood food challenge. METHODS: We recruited 53 participants from a cohort of consecutive children scheduled for an open-labelled peanut food challenge (OFC) by their paediatric allergist. Participants underwent skin prick test (SPT) measurement for sensitization to whole peanut extract, and serum was collected for Ara h2-specific IgE. FeNO was also measured in all cooperative children before the challenge. OFC and assessment of reaction were undertaken by clinicians blinded to test results. RESULTS: Ara h2-specific IgE and FeNO each showed improved diagnostic accuracy when compared to SPT. Receiver operator characteristic curve analysis gave an area under the curve (AUC) for Ara h2 sIgE of 0.84 (95% CI, 0.72-0.96). The AUC for FeNO, 0.83 (95% CI, 0.71-0.95), was equivalent to that of Ara h2. Combined AUC for SPT, sIgE to Ara h2 and FeNO was 0.96 (95% CI 0.90-1.00). There was no correlation between FeNO and serum nitrite levels (rs = -0.13, P = 0.6, n = 18). CONCLUSION AND CLINICAL RELEVANCE: Prospectively measured Ara h2-specific IgE improves diagnostic accuracy and reduces unsuccessful challenge to peanut. FeNO levels may provide improved diagnostic accuracy in a paediatric population undergoing OFC. The proposed FeNO-based diagnostic algorithm requires further validation studies.
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Alérgenos/imunologia , Arachis/efeitos adversos , Expiração , Óxido Nítrico , Hipersensibilidade a Amendoim/diagnóstico , Hipersensibilidade a Amendoim/imunologia , Adolescente , Algoritmos , Especificidade de Anticorpos/imunologia , Antígenos de Plantas/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Nitritos/sangue , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Fatores de Risco , Testes CutâneosRESUMO
BACKGROUND: Herpes zoster and cancer are associated with immunosuppression. Zoster occurs more often in patients with an established cancer diagnosis. Current evidence suggests some risk of cancer after zoster but is inconclusive. We aimed to assess the risk of cancer following zoster and the impact of prior zoster on cancer survival. METHODS: A primary care database retrospective cohort study was undertaken. Subjects with zoster were matched to patients without zoster. Risk of cancer following zoster was assessed by generating hazard ratios using Cox regression. Time to cancer was generated from the index date of zoster diagnosis. RESULTS: In total, 2054 cancers were identified in 74,029 patients (13,428 zoster, 60,601 matches). The hazard ratio for cancer diagnosis after zoster was 2.42 (95% confidence interval 2.21, 2.66) and the median time to cancer diagnosis was 815 days. Hazard ratios varied between cancers, and were highest in younger patients. There were more cancers in patients with zoster than those without for all age groups and both genders. Prior immunosuppression was not associated with change in risk, and diagnosis of zoster before cancer did not affect survival. CONCLUSION: This study establishes an association between zoster and future diagnosis of cancer having implications for cancer case finding after zoster diagnosis.
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Bases de Dados Factuais , Herpes Zoster/complicações , Neoplasias/diagnóstico , Atenção Primária à Saúde , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Herpes Zoster/mortalidade , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Neoplasias/virologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Adulto JovemRESUMO
BACKGROUND: One hypothesis has posited whether abnormal lipid metabolism might be a causal factor in the pathogenesis of osteoarthritis (OA). Routine statin use in clinical practice provides the basis for a natural experiment in testing this hypothesis. OBJECTIVE: To test the hypothesis that statins reduce the long-term occurrence of clinically defined OA. DESIGN: Cohort design with a 10-year follow-up. PARTICIPANTS: 16,609 adults cardiovascular disease cohorts aged 40 years and over from the UK General Practice Research Database with data available to 31 December 2006. INTERVENTION: Statins were summarised as annual mean daily dose and dose change over two-year time periods. MAIN MEASURES: Incident episode of clinically defined osteoarthritis was assessed within 2 years, and at 4-year and 10-year follow-up time periods, using Cox and discrete time survival analysis. Covariates included age, gender, deprivation, body mass index, cholesterol level, pain-modifying drug co-therapies, and duration and severity of cardiovascular disease. KEY RESULTS: Higher therapeutic dose of statin, with a treatment duration of at least 2 years was associated with a significant reduction in clinical OA compared to non-statin users in the follow-up time period. The estimated adjusted rate ratios were as follows: lowest statin dose quartile 1: 2.5 (95 % CI 2.3, 2.9); quartile 2: 1.3 (1.1, 1.5); quartile 3: 0.8 (0.7, 0.95); and highest statin dose quartile 4: 0.4 (0.3, 0.5). The largest statin dose increments were associated with significant reductions estimated at 18 % in OA outcome within 2 years and 40 % after 4 years, compared to non-statin users. CONCLUSIONS: This longitudinal study from a national clinical practice setting provides evidence that higher statin dose and larger statin dose increments were associated with a reduction in clinically defined OA outcome.
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Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Osteoartrite/tratamento farmacológico , Osteoartrite/epidemiologia , Vigilância da População/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico , Resultado do TratamentoRESUMO
There is increasing interest in using the cyanogenic properties of Pseudomonas aeruginosa to develop a nonmicrobiological method for its detection. Prior to this, the variation in cyanide production between different P. aeruginosa strains needs to be investigated. Hydrogen cyanide (HCN) released into the gas phase by 96 genotyped P. aeruginosa samples was measured using selected ion flow tube-mass spectrometry after 24, 48, 72 and 96 h of incubation. The HCN produced by a range of non-P. aeruginosa cultures and incubated blank plates was also measured. All P. aeruginosa strains produced more HCN than the control samples, which generated extremely low levels. Analysis across all time-points demonstrated that nonmucoid samples produced more HCN than the mucoid samples (p=0.003), but this relationship varied according to strain. There were clear differences in the headspace HCN concentration for different strains. Multivariate analysis of headspace HCN for the commonest strains (Liverpool, Midlands_1 and Stoke-on-Trent, UK) revealed a significant effect of strain (p<0.001) and a borderline interaction of strain and phenotype (p=0.051). This evidence confirms that all P. aeruginosa strains produce HCN but to varying degrees and generates interest in the possible future clinical applications of the cyanogenic properties of P. aeruginosa.
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Cianeto de Hidrogênio/metabolismo , Infecções por Pseudomonas/diagnóstico , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/metabolismo , Humanos , Cianeto de Hidrogênio/análiseRESUMO
BACKGROUND: Non-invasive ventilation (NIV) is an established treatment option for cystic fibrosis (CF) patients with type 2 respiratory failure but the benefits of this therapy remain unclear. This study examined the long-term outcomes and response to NIV in a large adult CF cohort. METHODS: All patients attending a UK adult CF Centre receiving NIV as treatment for hypercapnic respiratory failure over a nine-year period were studied prospectively. Detailed clinical data was recorded and longitudinal data measurements were examined for the three years pre and post NIV initiation to assess effect of this intervention. RESULTS: 94 patients, mean age 29.9 (SD 9.7) years, percent predicted FEV1 21.5 (7.3), received NIV. All patients commenced NIV in a hospital setting. 21 remain alive, 24 received double lung transplant, 49 died without lung transplantation. NIV use was associated with a stabilisation and improvement in both FEV1 and FVC from NIV set up to three years post follow-up, in addition to an increase in body mass index and attenuation of PCO2 (all p<0.001). No single parameter was found to predict long-term NIV response but baseline PCO2 (p=0.005), CRP (p=0.004) and age (p=0.009) were identified as independent predictors of mortality. CONCLUSIONS: NIV use in CF adults is associated with improvements in lung function and attenuation of hypercapnia which is maintained for up to three years post NIV initiation. Outcomes for CF patients with severe pulmonary disease commenced on NIV have significantly improved with fifty percent of patients expected to survive for approximately five years.
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Fibrose Cística/terapia , Ventilação não Invasiva , Insuficiência Respiratória/terapia , Adulto , Índice de Massa Corporal , Fibrose Cística/fisiopatologia , Feminino , Humanos , Transplante de Pulmão/estatística & dados numéricos , Masculino , Troca Gasosa Pulmonar , Testes de Função Respiratória , Insuficiência Respiratória/fisiopatologia , Reino UnidoRESUMO
OBJECTIVE: To identify the methods used in population-based epidemiological studies to diagnose radiographic foot osteoarthritis (OA) and to estimate the population prevalence of radiographic foot OA. METHOD: Electronic databases searched included Medline, Embase, CINAHL and Ageline (inception to May 2009). The search strategy combined search terms for radiography, OA, foot, and specific foot joints. Predetermined selection criteria were applied. Data extracted from each paper included: sample population, radiographic views taken, foot joints examined, scoring system used, definition of OA applied, reliability of radiographic scoring and prevalence of radiographic OA in the foot. RESULTS: Titles and abstracts of 1035 papers were reviewed and full-texts of 21 papers were obtained. Fifteen papers met inclusion criteria and a further 12 papers were included after screening references. Radiographic views were frequently not specified (NS) but a combination of antero-posterior (AP) and lateral (Lat) views was most commonly reported. The first metatarsophalangeal (MTP) joint was the most commonly examined joint (n=20, 74%). Nineteen studies (70%) used the Kellgren and Lawrence (K&L) grading system, 95% of which defined OA as K&L grade> or =2. Estimates of the prevalence of radiographic first MTP joint OA (defined as K&L> or =2) in middle-aged to older adults ranged from 6.3 to 39%. Significant statistical heterogeneity prevented pooling of prevalence estimates. CONCLUSION: There are comparatively few studies examining radiographic foot OA. Existing studies mainly focus on the first MTP joint and use the K&L grading system. Future studies are needed to quantify the prevalence of radiographic OA at the different joint complexes within the foot.
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Articulações do Pé/diagnóstico por imagem , Osteoartrite/epidemiologia , Humanos , Osteoartrite/diagnóstico por imagem , Osteoartrite/fisiopatologia , Prevalência , Radiografia , Índice de Gravidade de DoençaRESUMO
OBJECTIVES: (1) To examine the relationship of personality traits and diabetes health threat communication (DHTC) to the coping strategies of newly diagnosed diabetes patients; (2) to determine to what extent these postulated effects are mediated by illness representations (IRs). DESIGN: A longitudinal prospective study based on the common sense model. METHODS: Patients were assessed shortly after diagnosis and 2 years after the diagnosis of diabetes. Personality traits (Mini-markers) were assessed at baseline. The DHTC Questionnaire was completed at baseline and 2 years. The Revised Illness Perception Questionnaire and the coping orientation to problems experienced were completed at 2 years. Mediation by IRs of the potential influence of personality and DHTC on coping behaviour was assessed by the method of Baron and Kenny. RESULTS: Multiple regression analyses showed that educational level, agreeableness, openness/intellect, conscientiousness, and perceptions of a more reassuring health message since diagnosis were related to more adaptive coping (e.g., active coping, planning). The association of openness and perceived reassuring health message with active coping showed complete mediation by illness coherence and personal control. Openness led to seeking emotional support mediated by perceived personal control. Coherence associated with (partial mediation) the relation of openness to planning. Similarly, personal control and coherence mediated the relation of openness to positive reinterpretation and growth (PRG). Agreeableness had a direct relationship with active coping and PRG but led to planning and seeking instrumental support mediated by perceived treatment effectiveness. Perceptions of a threatening health message were associated with seeking instrumental and emotional support and this was mediated by symptom perception but threat had a direct relationship with planning. CONCLUSIONS: Both personality traits and health threat communication predict the way individuals cope with diabetes. The relationships of these factors are largely mediated through measurable IRs. The results suggest targets for intervention to achieve greater problem-focused coping.
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Adaptação Psicológica , Ansiedade/psicologia , Comunicação , Diabetes Mellitus/psicologia , Comportamento de Doença , Inventário de Personalidade/estatística & dados numéricos , Adolescente , Adulto , Idoso , Feminino , Humanos , Controle Interno-Externo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Resolução de Problemas , Estudos Prospectivos , Autocuidado/psicologia , Autoeficácia , Adulto JovemRESUMO
BACKGROUND: Fractures through the proximal femur are broadly grouped into intertrochanteric fractures and intracapsular fractures. It is not clear why a patient may sustain an intertrochanteric fracture as compared with an intracapsular fracture. There is an established relationship between relative hip retroversion and the development of osteoarthritis. We postulate retroversion also may be a risk factor for having intracapsular fractures develop. QUESTIONS/PURPOSES: We looked specifically at the geometry of the hip to analyze the possibility of a relationship between acetabular version, femoral version, and Mckibbin's instability index and fracture type. PATIENTS AND METHODS: We recruited 40 patients with fractures of the femoral neck for the study. There were 15 men and 25 women with a mean age of 80 years (range, 57-92 years). There were 14 intertrochanteric fractures and 26 intracapsular fractures. After treating their fracture, the contralateral hip was scanned in a CT scanner and assessed by two independent observers to establish the acetabular and femoral version. RESULTS: We found no correlation between proximal femoral fracture type and the contralateral femoral version, femoral neck length, acetabular version, or Mckibbin's instability index or between fracture type and age or gender. CONCLUSIONS: There appears to be no correlation between proximal femoral fracture type and acetabular or femoral version. LEVEL OF EVIDENCE: Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.
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Acetábulo/patologia , Fraturas do Colo Femoral/patologia , Fêmur/patologia , Luxação do Quadril/patologia , Fraturas do Quadril/patologia , Acetábulo/cirurgia , Idoso , Idoso de 80 Anos ou mais , Mau Alinhamento Ósseo/complicações , Mau Alinhamento Ósseo/patologia , Feminino , Fraturas do Colo Femoral/classificação , Fraturas do Colo Femoral/etiologia , Fêmur/cirurgia , Luxação do Quadril/complicações , Fraturas do Quadril/classificação , Fraturas do Quadril/etiologia , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
Much has been learned about the electromagnetic interaction between Jupiter and its satellite Io from in situ observations. Io, in its motion through the Io plasma torus at Jupiter, continuously generates an Alfvén wing that carries two billion kilowatts of power into the jovian ionosphere. Concurrently, Io is acted upon by a J x B force tending to propel it out of the jovian system. The energy source for these processes is the rotation of Jupiter. This unusual planet-satellite coupling serves as an archetype for the interaction of a large moving conductor with a magnetized plasma, a problem of general space and astrophysical interest.
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The first of at least nine bow shock crossings observed on the inbound pass of Voyager 2 occurred at 98.8 Jupiter radii (R(J)) with final entry into the magnetosphere at 62 R(J). On both the inbound and outbound passes the plasma showed a tendency to move in the direction of corotation, as was observed on the inbound pass of Voyager 1. Positive ion densities and electron intensities observed by Voyager 2 are comparable within a factor of 2 to those seen by Voyager 1 at the same radial distance from Jupiter; the composition of the magnetospheric plasma is again dominated by heavy ions with a ratio of mass density relative to hydrogen of about 100/1. A series of dropouts of plasma intensity near Ganymede may be related to a complex interaction between Ganymede and the magnetospheric plasma. From the planetary spin modulation of the intensity of plasma electrons it is inferred that the plasma sheet is centered at the dipole magnetic equator out to a distance of 40 to 50 R(J) and deviates from it toward the rotational equator at larger distances. The longitudinal excursion of the plasma sheet lags behind the rotating dipole by a phase angle that increases with increasing radial distance.
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Transgenic mice containing intact copies of the human immunodeficiency virus (HIV) proviral DNA were constructed. Founder animals were not viremic for HIV and remained healthy during a 9-month observation period. After being mated with nontransgenic animals, one founder mouse (No. 13) gave rise to F1 progeny that developed a disease syndrome characterized by marked epidermal hyperplasia, lymphadenopathy, splenomegaly, pulmonary lymphoid infiltrates, growth retardation, and death by day 25 of life. Infectious HIV, indistinguishable from parental virus by immunoblot analysis, was recovered from the spleen, lymph nodes, and skin of five of five affected animals.
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Síndrome da Imunodeficiência Adquirida/microbiologia , DNA Viral , Modelos Animais de Doenças , HIV/genética , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/patologia , Animais , Sondas de DNA , DNA Viral/análise , Epiderme/patologia , HIV/imunologia , HIV/isolamento & purificação , Anticorpos Anti-HIV/análise , Pulmão/patologia , Linfonodos/microbiologia , Linfonodos/patologia , Camundongos , Camundongos Transgênicos , Hibridização de Ácido Nucleico , Pele/microbiologia , Pele/patologia , Baço/microbiologia , Baço/patologiaRESUMO
Extensive measurements of low-energy positive ions and electrons were made throughout the Jupiter encounter of Voyager 1. The bow shock and magneto-pause were crossed several times at distances consistent with variations in the upstream solar wind pressure measured on Voyager 2. During the inbound pass, the number density increased by six orders of magnitude between the innermost magnetopause crossing at approximately 47 Jupiter radii and near closest approach at approximately 5 Jupiter radii; the plasma flow during this period was predominately in the direction of corotation. Marked increases in number density were observed twice per planetary rotation, near the magnetic equator. Jupiterward of the Io plasma torus, a cold, corotating plasma was observed and the energylcharge spectra show well-resolved, heavy-ion peaks at mass-to-charge ratios A/Z* = 8, 16, 32, and 64.
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Extensive measurements of low-energy positive ions and electrons in the vicinity of Uranus have revealed a fully developed magnetosphere. The magnetospheric plasma has a warm component with a temperature of 4 to 50 electron volts and a peak density of roughly 2 protons per cubic centimeter, and a hot component, with a temperature of a few kiloelectron volts and a peak density of roughly 0.1 proton per cubic centimeter. The warm component is observed both inside and outside of L = 5, whereas the hot component is excluded from the region inside of that L shell. Possible sources of the plasma in the magnetosphere are the extended hydrogen corona, the solar wind, and the ionosphere. The Uranian moons do not appear to be a significant plasma source. The boundary of the hot plasma component at L = 5 may be associated either with Miranda or with the inner limit of a deeply penetrating, solar wind-driven magnetospheric convection system. The Voyager 2 spacecraft repeatedly encountered the plasma sheet in the magnetotail at locations that are consistent with a geometric model for the plasma sheet similar to that at Earth.
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The plasma science experiment on Voyager 2 made observations of the plasma environment in Neptune's magnetosphere and in the surrounding solar wind. Because of the large tilt of the magnetic dipole and fortuitous timing, Voyager entered Neptune's magnetosphere through the cusp region, the first cusp observations at an outer planet. Thus the transition from the magnetosheath to the magnetosphere observed by Voyager 2 was not sharp but rather appeared as a gradual decrease in plasma density and temperature. The maximum plasma density observed in the magnetosphere is inferred to be 1.4 per cubic centimeter (the exact value depends on the composition), the smallest observed by Voyager in any magnetosphere. The plasma has at least two components; light ions (mass, 1 to 5) and heavy ions (mass, 10 to 40), but more precise species identification is not yet available. Most of the plasma is concentrated in a plasma sheet or plasma torus and near closest approach to the planet. A likely source of the heavy ions is Triton's atmosphere or ionosphere, whereas the light ions probably escape from Neptune. The large tilt of Neptune's magnetic dipole produces a dynamic magnetosphere that changes configuration every 16 hours as the planet rotates.
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Extensive measurements of low-energy plasma electrons and positive ions were made during the Voyager 1 encounter with Saturn and its satellites. The magnetospheric plasma contains light and heavy ions, probably hydrogen and nitrogen or oxygen; at radial distances between 15 and 7 Saturn-radii (Rs) on the inbound trajectory, the plasma appears to corotate with a velocity within 20 percent of that expected for rigid corotation. The general morphology of Saturn's magnetosphere is well represented by a plasma sheet that extends from at least 5 to 17 Rs, is symmetrical with respect to Saturn's equatorial plane and rotation axis, and appears to be well ordered by the magnetic shell parameter L (which represents the equatorial distance of a magnetic field line measured in units of Rs). Within this general configuration, two distinct structures can be identified: a central plasma sheet observed from L = 5 to L = 8 in which the density decreases rapidly away from the equatorial plane, and a more extended structure from L = 7 to beyond 18 Rs in which the density profile is nearly flat for a distance +/- 1.8 Rs off the plane and falls rapidly thereafter. The encounter with Titan took place inside the magnetosphere. The data show a clear signature characteristic of the interaction between a subsonic corotating magnetospheric plasma and the atmospheric or ionospheric exosphere of Titan. Titan appears to be a significant source of ions for the outer magnetosphere. The locations of bow shock crossings observed inbound and outbound indicate that the shape of the Saturnian magnetosphere is similar to that of Earth and that the position of the stagnation point scales approximately as the inverse one-sixth power of the ram pressure.
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Results of measurements of plasma electrons and poitive ions made during the Voyager 2 encounter with Saturn have been combined with measurements from Voyager 1 and Pioneer 11 to define more clearly the configuration of plasma in the Saturnian magnetosphere. The general morphology is well represented by four regions: (i) the shocked solar wind plasma in the magnetosheath, observed between about 30 and 22 Saturn radii (RS) near the noon meridian; (ii) a variable density region between approximately 17 RS and the magnetopause; (iii) an extended thick plasma sheet between approximately 17 and approximately 7 RS symmetrical with respect to Saturn's equatorial plane and rotation axis; and (iv) an inner plasma torus that probably originates from local sources and extends inward from L approximately 7 to less than L approximately 2.7 (L is the magnetic shell parameter). In general, the heavy ions, probably O(+), are more closely confined to the equatorial plane than H(+), so that the ratio of heavy to light ions varies along the trajectory according to the distance of the spacecraft from the equatorial plane. The general configuration of the plasma sheet at Saturn found by Voyager 1 is confirmed, with some notable differences and additions. The "extended plasma sheet," observed between L approximately 7 and L approximately 15 by Voyager 1 is considerably thicker as observed by Voyager 2. Inward of L approximately 4, the plasma sheet collapses to a thin region about the equatorial plane. At the ring plane crossing, L approximately 2.7, the observations are consistent with a density of O(+) of approximately 100 per cubic centimeter, with a temperature of approximately 10 electron volts. The location of the bow shock and magnetopause crossings were consistent with those previously observed. The entire magnetosphere was larger during the outbound passage of Voyager 2 than had been previously observed; however, a magnetosphere of this size or larger is expected approximately 3 percent of the time.
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Atherosclerosis is the leading cause of death in the United States, and human cytomegalovirus (HCMV), a member of the herpes virus family, may play a role in the development of the disease. We previously showed that HCMV regulated endothelial apoptosis. In this study, we investigated the induction of apoptosis and signal transduction pathways regulating this process in HCMV-infected endothelial cells. As observed previously, HCMV induced a typical cytopathic effect in human aortic endothelial cells (HAECs), ie, the formation of single nucleated or multinucleated giant cells. Although infected HAECs were resistant to apoptosis at earlier stages of infection, they became apoptotic with prolonged infection as demonstrated by positive staining using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL). This apoptotic process was mediated by the caspase-dependent mitochondrial apoptotic pathway as indicated by increased expression and cleavage of caspases 3 and 9 as well as increased expressions of pro-apoptotic molecules Bax and Bak. Blocking caspases 3 or 9 significantly inhibited the HCMV-induced apoptosis. Further exploration of the upstream pathway demonstrated upregulation of the tumor suppressor p53 gene and activation of the ataxia telangiectasia mutant (ATM) pathway in the infected cells. Blocking p53 inhibited HCMV-stimulated Bax and Bak expression as well as caspase-3 activation and blocking the ATM pathway inhibited HCMV-stimulated p53 activation. Although early infection may render cells antiapoptotic, prolonged infection, however, induced endothelial apoptosis through ATM and p53-dependent activation of the mitochondrial death pathway. This proapoptotic effect may be relevant to endothelial dysfunction and HCMV-associated vascular diseases.
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Apoptose , Citomegalovirus/patogenicidade , Endotélio Vascular/virologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia , Caspases/metabolismo , Proteínas de Ciclo Celular , Dano ao DNA , Proteínas de Ligação a DNA , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Proteínas Supressoras de TumorRESUMO
Packaging companies must carefully monitor retail and consumer trends to best utilize, direct, or prioritize their research dollars in developing packaging and packaging systems to meet these demands. This paper reviews packaging developments that are resulting from numerous trends taking place in the meat industry and in the retail sector. Current case ready packaging solutions that meet the needs of retailers to reduce labor in the back of the retail stores, and the consumer needs for a fresh product with excellent quality and palatability are also discussed. It will also review the current packaging options that are being developed to help consumers battle their "time crunch" with ready meal solutions. Finally, the necessity to increase food safety or eliminate pathogens while producing a high quality product continues to drive packaging development. Current systems and packaging available for post packaging pasteurization will be discussed.