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1.
Nat Commun ; 9(1): 3709, 2018 09 13.
Article in English | MEDLINE | ID: mdl-30213944

ABSTRACT

The radiant energy budget and internal heat are fundamental properties of giant planets, but precise determination of these properties remains a challenge. Here, we report measurements of Jupiter's radiant energy budget and internal heat based on Cassini multi-instrument observations. Our findings reveal that Jupiter's Bond albedo and internal heat, 0.503 ± 0.012 and 7.485 ± 0.160 W m-2 respectively, are significantly larger than 0.343 ± 0.032 and 5.444 ± 0.425 Wm-2, the previous best estimates. The new results help constrain and improve the current evolutionary theories and models for Jupiter. Furthermore, the significant wavelength dependency of Jupiter's albedo implies that the radiant energy budgets and internal heat of the other giant planets in our solar system should be re-examined. Finally, the data sets of Jupiter's characteristics of reflective solar spectral irradiance provide an observational basis for the models of giant exoplanets.

2.
J Dairy Sci ; 97(8): 4876-85, 2014.
Article in English | MEDLINE | ID: mdl-24931524

ABSTRACT

This study was conducted to evaluate the association between subclinical intramammary infection (IMI) with coagulase-negative staphylococci (CNS), mammary quarter milk somatic cell count (SCC), and persistence of IMI in dairy cattle. Convenience samples of CNS isolates harvested from milk samples of subclinically infected mammary quarters collected between 4 and 2wk before drying-off, between 2wk before drying-off and the day of drying-off, within 24h after calving, between 1 and 2wk after calving, and during lactation were evaluated. Isolates were obtained from the Canadian Bovine Mastitis Research Network culture bank and were identified to the species level using rpoB gene sequencing. Cow and quarter-level data were obtained from the Canadian Bovine Mastitis Research Network database and used for statistical analyses. In addition, for mammary quarters that had more than one isolation of the same CNS species at different time points, the isolates were evaluated using pulsed-field gel electrophoresis to identify persistent IMI. Milk SCC was compared between mammary quarters infected with different CNS species and to a cohort of uninfected mammary quarters. A total of 877 isolates from 643 mammary quarters of 555 cows on 89 Canadian dairy farms were identified to the species level. Twenty different species were identified, with Staphylococcus chromogenes being the most common species identified (48% of isolates), followed by Staphylococcus simulans (19%) and Staphylococcus xylosus (10%). Of the 20 species identified, only 9 species were found in persistently infected quarters. Milk SCC was significantly higher in the CNS-infected mammary quarters than in the uninfected control quarters for 8 of the 20 species studied. Also, mean SCC differed significantly between mammary quarters infected with different CNS species. Within a given species, a high degree of variability was noted in milk SCC. These data corroborate recent data from Europe with regard to the predominance of certain species of CNS (e.g., Staph. chromogenes). In addition, some species of CNS appear to have a greater effect on milk SCC. Finally, some CNS species are associated with persistent IMI suggesting that some species (e.g., Staph. chromogenes and Staph. simulans) are better host-adapted, whereas others may have an environmental reservoir.


Subject(s)
Cell Count/veterinary , Milk/cytology , Milk/microbiology , Staphylococcal Infections/microbiology , Staphylococcal Infections/veterinary , Staphylococcus/classification , Animals , Canada , Cattle , Coagulase/metabolism , Electrophoresis, Gel, Pulsed-Field , Female , Food Contamination/analysis , Food Microbiology , Lactation , Mastitis, Bovine/microbiology
3.
Nano Lett ; 13(3): 861-5, 2013 Mar 13.
Article in English | MEDLINE | ID: mdl-23398085

ABSTRACT

The potential for scale-up coupled with minimized system size is likely to be a major determining factor in the realization of applicable quantum information systems. Nanofabrication technology utilizing the III-V semiconductor system provides a path to scalable quantum bit (qubit) integration and a materials platform with combined electronic/photonic functionality. Here, we address the key requirement of qubit-site and emission energy control for scale-up by demonstrating uniform arrays of III-V nanowires, where each nanowire contains a single quantum dot. Optical studies of single nanowire quantum dots reveal narrow linewidth exciton and biexciton emission and clear state-filling at higher powers. Individual nanowire quantum dots are shown to emit nonclassically with clear evidence of photon antibunching. A model is developed to explain unexpectedly large excited state separations as revealed by photoluminescence emission spectra. From measurements of more than 40 nanowire quantum dots, we find emission energies with an ensemble broadening of 15 meV. The combination of deterministic site control and the narrow distribution in ensemble emission energy results in a system readily capable of scaling for multiqubit quantum information applications.

4.
J Antimicrob Chemother ; 60(3): 677-80, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17623694

ABSTRACT

OBJECTIVES: A validated microbiological assay was used to measure concentrations of iclaprim (AR-100) in plasma, bronchial mucosa (BM), alveolar macrophages (AM) and epithelial lining fluid (ELF) after a single 1.6 mg/kg intravenous 60 min iv infusion of iclaprim. METHODS: Male volunteers were randomly allocated to three nominal sampling time intervals 1-2 h (Group A), 3-4 h (Group B) and 5.5-7.0 h (Group C) after the start of the drug infusion. RESULTS: Mean iclaprim concentrations in plasma, BM, AM and ELF, respectively, were for Group A 0.59 mg/L (SD 0.18), 0.51 mg/kg (SD 0.17), 24.51 mg/L (SD 21.22) and 12.61 mg/L (SD 7.33); Group B 0.24 mg/L (SD 0.05), 0.35 mg/kg (SD 0.17), 7.16 mg/L (SD 1.91) and 6.38 mg/L (SD 5.17); and Group C 0.14 mg/L (SD 0.05), no detectable level in BM, 5.28 mg/L (SD 2.30) and 2.66 mg/L (SD 2.08). CONCLUSIONS: Iclaprim concentrations in ELF and AM exceeded the MIC(90) for penicillin-susceptible Streptococcus pneumoniae (MIC90 0.06 mg/L), penicillin-intermediate S. pneumoniae (MIC90 2 mg/L), penicillin-resistant S. pneumoniae (MIC90 4 mg/L) for 7, 7 and 4 h, respectively, and Chlamydia pneumoniae (MIC90 0.5 mg/L) for 7 h. Mean iclaprim concentrations in ELF exceeded the MIC90 for Haemophilus influenzae (MIC90 4 mg/L) and Moraxella catarrhalis (MIC90 8 mg/L) for up to 4 and 2 h, respectively; in AM the MIC90 was exceeded for up to 7 h. Furthermore, the MIC90 for methicillin-resistant Staphylococcus aureus of 0.12 mg/L was exceeded at all sites for up to 7 h. These data suggest that iclaprim reaches lung concentrations that should be effective in the treatment of community-acquired pneumonia.


Subject(s)
Anti-Bacterial Agents/pharmacokinetics , Bronchi/metabolism , Folic Acid Antagonists/pharmacokinetics , Macrophages, Alveolar/metabolism , Pyrimidines/pharmacokinetics , Respiratory Mucosa/metabolism , Adult , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/blood , Bacillus/drug effects , Bronchoscopy , Epithelium/metabolism , Folic Acid Antagonists/administration & dosage , Folic Acid Antagonists/blood , Humans , Infusions, Intravenous , Male , Microbial Sensitivity Tests , Pyrimidines/administration & dosage , Pyrimidines/blood
5.
Phys Rev Lett ; 98(2): 026806, 2007 Jan 12.
Article in English | MEDLINE | ID: mdl-17358634

ABSTRACT

We show that by illuminating an InGaAs/GaAs self-assembled quantum dot with circularly polarized light, the nuclei of atoms constituting the dot can be driven into a bistable regime, in which either a thresholdlike enhancement or reduction of the local nuclear field by up to 3 T can be generated by varying the pumping intensity. The excitation power threshold for such a nuclear spin "switch" is found to depend on both the external magnetic and electric fields. The switch is shown to arise from the strong feedback of the nuclear spin polarization on the dynamics of the spin transfer from electrons to the nuclei of the dot.

6.
Neurourol Urodyn ; 24(1): 81-8, 2005.
Article in English | MEDLINE | ID: mdl-15570578

ABSTRACT

AIMS: Prostate stromal cell cultures are used in vitro to study the cellular pathophysiology of benign prostatic hyperplasia (BPH), but their functional properties are poorly understood. This study characterized intracellular Ca2+ ([Ca2+]i) regulation in a cultured cell line in comparison to freshly isolated cells, as a background to understanding contractile regulation and cellular proliferation in this tissue. METHODS: Prostate stromal cells were isolated from either PrS6 cell cultures, with an extended life span by transfection with the SV40 T-antigen, tsA58-U19, or freshly obtained transition zone prostate samples, primary cells. [Ca2+]i was measured in vitro with the indicator Fura-2 by epifluorescence microscopy. RESULTS: Phenylephrine, high-K+, and caffeine induced Ca2+-transients in primary cells (resting [Ca2+]i 94 +/- 8 nM, n = 29; peak 193 +/- 26 nM, n = 19). In PrS6 cells resting [Ca2+]i was 96 +/- 8 nM (n = 78) and in 34 of these 78 cells, 30 microM phenylephrine increased [Ca2+]i to 296 +/- 28 nM. 5-methyl-urapidil (10-30 microM) inhibited this response in 10 of 16 cells. Spontaneous Ca2+-transients were also observed in 91% of phenylephrine-responsive cells, but in only 20% of non-responsive cells (P < 0.01). Ca2+-transients were also induced by high-K+ solution, and 20 mM caffeine. The latter abolished the response to subsequent phenylephrine application. Depletion of intracellular Ca2+ stores by caffeine or restoration from a Ca2+-free superfusate caused a substantial rise of [Ca2+]i. CONCLUSIONS: PrS6 prostate stromal cells express functional alpha1-adrenoceptors associated with spontaneous intracellular Ca2+-transients. They exhibit functional Ca2+ channels, intracellular Ca2+ stores, and Ca2+ entry induced by store depletion. Stromal cultures can therefore be used to characterize the cellular physiology of prostate stromal cell contraction and proliferation.


Subject(s)
Calcium/metabolism , Prostate/cytology , Stromal Cells/metabolism , Adrenergic alpha-Agonists/pharmacology , Biological Transport/drug effects , Biological Transport/physiology , Cells, Cultured , Humans , Male , Muscle, Smooth/cytology , Phenylephrine/pharmacology , Stromal Cells/cytology , Stromal Cells/drug effects
7.
Psychol Aging ; 18(3): 474-86, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14518809

ABSTRACT

Using a sample of 167 women and 121 men, aged 65-87, this study tested the hypothesis that self-efficacy beliefs of older persons are significantly stronger predictors of death fears than are demographics, social support, and physical health variables used in earlier predictor models. Standard self-report measures were used to assess all predictor variables, including perceived self-efficacy in 8 different domains. Findings from a series of hierarchical regression analyses that were conducted separately for men and women supported the hypothesis concerning the superiority of self-efficacy variables as predictors of fear of the unknown after death and fear of dying, with spiritual health efficacy and instrumental efficacy being the most potent predictors of death fears for women and men, respectively.


Subject(s)
Aging/psychology , Attitude to Death , Fear/psychology , Self Efficacy , Aged , Aged, 80 and over , Female , Humans , Male , Predictive Value of Tests , Psychometrics , Religion
8.
Genet Soc Gen Psychol Monogr ; 128(2): 139-63, 2002 May.
Article in English | MEDLINE | ID: mdl-12194420

ABSTRACT

The purposes of this study were to examine the structural properties of the social support networks of female survivors of violence and abuse and to investigate the quality of the relationship, and specific level of satisfaction, survivors have with their social support networks. Participants averaged 5.8 persons in their social support networks. Their levels of satisfaction with the emotional, practical, financial, guidance, and socializing support they received from members of their social support networks were higher with respect to close friends and coworkers than with respect to family members and professionals (e.g., attorneys and social workers). The most common type of support provided by close friends who were themselves victims of abuse was emotional, guidance, and socializing support, and the most satisfying support was the financial and practical help that came from parents or family. An interesting finding was the significant presence of men in the survivors' social support networks. Overall satisfaction with the quality of support from the social support networks was high, and satisfaction with support from men was comparable, if not higher, than support from women. Multiple regression models revealed that satisfaction with support networks was a potent predictor of self-esteem, emotional health, and loneliness. Intimacy, especially in terms of exclusiveness and trust or loyalty, with at least a few members of the support network contributed significantly to the variance in self-esteem, emotional health, and loneliness among the abused women. The size of the support network also emerged as a limited contributor to well-being. Implications and applications are discussed for professionals working with female survivors of abuse.


Subject(s)
Child Abuse/psychology , Interpersonal Relations , Social Support , Survivors/psychology , Activities of Daily Living , Adult , Affect , Child , Female , Humans , Loneliness/psychology , Self Concept , Surveys and Questionnaires
9.
Gerontologist ; 41(6): 787-98, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11723347

ABSTRACT

PURPOSE OF THE STUDY: The overall purpose of the study was to examine the relationship between widowed persons' baseline assessments of self-efficacy beliefs and their ratings of perceived health-related quality of life, life satisfactions, and self-esteem obtained in an 18-month follow-up. DESIGN AND METHOD: At Time 1, a survey of sociodemographics, a multidimensional measure of global self-efficacy, and a domain-specific measure of self-efficacy, having eight subscales of self-efficacy (interpersonal, instrumental, emotional, social support, nutritional, physical, financial, and spiritual) were administered to a group of 231 widows and widowers to obtain baseline assessments of their self-efficacy beliefs. At Time 2, a follow-up of 211 widows and widowers was conducted to obtain their perceptions of health-related quality of life, life satisfactions, and levels of self-esteem 24 months following spousal loss and to assess whether self-efficacy beliefs play a predictive role in widowed individuals' perceptions of their health-related quality of life, life satisfactions, and self-esteem. RESULTS: A series of gender-specific multiple regression analyses models revealed that widows and widowers differ significantly with respect to the relationship between specific domains of self-efficacy and their perceived quality of life in the longer term following spousal loss. IMPLICATIONS: Implications of the findings are discussed for clinicians and health professionals working with bereaved spouses in terms of intervention programs for retraining of self-efficacy.


Subject(s)
Bereavement , Quality of Life , Self Efficacy , Widowhood/psychology , Aged , Aged, 80 and over , Alberta , Female , Follow-Up Studies , Humans , Linear Models , Male , Multivariate Analysis , Personal Satisfaction , Self Concept
10.
Child Welfare ; 80(5): 656-67, 2001.
Article in English | MEDLINE | ID: mdl-11678422

ABSTRACT

Each year, thousands of children who cross international borders are destined for homes with adoptive families. For most, this journey from their homeland brings them to loving new homes where they will thrive and prosper. For others, the journey is hazardous and the destination uncertain.


Subject(s)
Adoption , Child Welfare , International Cooperation , Social Work/standards , Child , Child Advocacy , Ethics , Female , Humans , Infant, Newborn , Organizational Case Studies , Organizational Policy , Social Work/organization & administration , United Kingdom , United States
11.
J Vasc Interv Radiol ; 12(5): 629-32, 2001 May.
Article in English | MEDLINE | ID: mdl-11340144

ABSTRACT

Endoleaks are defined as persistent perfusion of an abdominal aortic aneurysm (AAA) after endovascular stent-graft deployment. The authors describe their experience treating six endoleaks with the liquid embolic agent Onyx (ethylene-vinyl-alcohol copolymer). Complete endoleak occlusion was achieved in five of six cases. Follow-up imaging has demonstrated decreased aneurysm diameter in all patients 7-29 weeks (mean = 19.2 weeks) after treatment.


Subject(s)
Aortic Aneurysm, Abdominal/surgery , Embolization, Therapeutic/methods , Polyvinyls/therapeutic use , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Postoperative Complications
13.
Cancer Nurs ; 24(1): 12-9, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11219418

ABSTRACT

Quality of life (QOL) as an outcome for cancer treatment has been studied primarily in urban populations. Yet, descriptions of rural dwellers suggest that their perception of QOL may differ from that of their urban counterparts. The purpose of this study was to examine QOL in people with a cancer diagnosis of at least 1 month duration in two similar rural northeastern states. The Functional Assessment of Cancer Therapy General (FACT G) scale was completed by 344 respondents. The mean QOL score was 89.41 +/- 16.55. State of residence, gender, known recurrence, and marital status were significant predictors of QOL, explaining 18.3% of the variance in this study. Age, education level, income, type of cancer, living arrangements, and time since diagnosis were not predictive. The QOL scores in this rural sample were higher than those reported earlier for predominantly urban dwellers. Future research is needed to understand these differences.


Subject(s)
Neoplasms/psychology , Quality of Life , Rural Population , Adult , Aged , Aged, 80 and over , Female , Humans , Maine , Male , Middle Aged , Multivariate Analysis , Regression Analysis , Socioeconomic Factors , Vermont
14.
Gerontologist ; 41(1): 69-81, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11220817

ABSTRACT

PURPOSE: This study examined the unique contribution of key existential factors to the prediction of psychological well-being of older adults following spousal loss. DESIGN AND METHOD: A number of measures to assess psychological well-being, sociodemographic standing, social resources, and religious and spiritual resources were administered to a volunteer sample of widows and widowers to test the hypothesis that existential factors such as personal meaning, religiosity, and spirituality are more potent predictors of psychological well-being than are previously hypothesized variables of sociodemographic, social support, and physical factors. RESULTS: A hierarchical regression analysis of the data supported the hypothesis that existential factors are major contributors to psychological well-being of older adults following spousal loss. Findings showed that widowers, compared to widows, scored lower on the measure of psychological well-being. IMPLICATIONS: Implications of the findings are discussed for practitioners working with bereaved spouses; suggestions for further research concerning bereavement and psychological well-being are made.


Subject(s)
Adaptation, Psychological , Bereavement , Widowhood/psychology , Adult , Age Factors , Aged , Aged, 80 and over , Analysis of Variance , Education , Employment , Female , Health Status , Humans , Income , Male , Regression Analysis , Religion , Research , Sampling Studies , Sex Factors , Social Support , Time Factors
15.
J Histochem Cytochem ; 49(2): 271-8, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11156695

ABSTRACT

The prostate grows slowly throughout adult life, leading to benign prostatic hyperplasia (BPH), which often results in urethral obstruction in later years. The symptoms of BPH are the second most common reason for surgery in men over 65. The aim of this study was to determine the relationship between cell proliferation and cell differentiation in BPH tissue. Using multiple antibodies, simultaneously detected with different fluorophore-conjugated secondary antibodies, several subpopulations of epithelial cells were detected. In addition to K14, basal cells also expressed keratins 15, 17, and 19 in various combinations, and some of the luminal cells also expressed K19 together with K8 and K18. Co-staining for cytokeratins and Ki-67 indicated that 44% of proliferative cells expressed K14 and 36% K19, although the difference was not statistically significant. This report provides a detailed description of the relationship between keratin expression and cell proliferation in the prostate and indicates that K19-positive cells form the link between the basal and luminal layers of the epithelium. (J Histochem Cytochem 49:271-278, 2001)


Subject(s)
Epithelial Cells/pathology , Keratins/metabolism , Prostate/pathology , Aged , Antibodies , Cell Compartmentation , Cell Differentiation , Cell Division , Epithelial Cells/metabolism , Humans , Immunohistochemistry , Keratins/immunology , Male , Middle Aged , Phenotype , Prostatic Hyperplasia/pathology
18.
Int J Aging Hum Dev ; 50(4): 361-83, 2000.
Article in English | MEDLINE | ID: mdl-11087112

ABSTRACT

Three hundred and thirty-one older adults participated in a study designed to examine their perceptions of what constitutes a reasonable quality of life. Participants responded to an open-ended questionnaire in which they were asked to state their priorities, preferences, aspirations, and concerns about their present and future quality of life. Responses were subjected to a principal components factor analysis which yielded four factors: 1) respondents' demands for specific guarantees; 2) respondents' aspirations and expectations for future quality of life; 3) fears and anxieties; and 4) external factors presenting a threat to quality of life. These factors accounted for 15 percent, 12 percent, 9.2 percent, and 7.1 percent, respectively, of the total variance. Additionally, data obtained from in-depth interviews with thirty-seven older adults were analyzed using a qualitative approach. Contrary to stereotypic notions that elderly persons are frail, vulnerable, and resigned to deteriorating conditions of well-being in late life, the results of both the qualitative and quantitative components of the study showed the majority of respondents as having clear demands for autonomy, control, and independence in making decisions, including the decision to terminate life. Implications are discussed in terms of future research on quality of life of older adults.


Subject(s)
Aged/psychology , Attitude to Health , Quality of Life/psychology , Self Efficacy , British Columbia , Data Interpretation, Statistical , Focus Groups , Freedom , Humans , Interviews as Topic , Patient Participation , Personal Satisfaction , Right to Die , Socioeconomic Factors , Surveys and Questionnaires
19.
Phys Rev Lett ; 84(4): 733-6, 2000 Jan 24.
Article in English | MEDLINE | ID: mdl-11017359

ABSTRACT

New information on the electron-hole wave functions in InAs-GaAs self-assembled quantum dots is deduced from Stark effect spectroscopy. Most unexpectedly it is shown that the hole is localized towards the top of the dot, above the electron, an alignment that is inverted relative to the predictions of all recent calculations. We are able to obtain new information on the structure and composition of buried quantum dots from modeling of the data. We also demonstrate that the excited state transitions arise from lateral quantization and that tuning through the inhomogeneous distribution of dot energies can be achieved by variation of electric field.

20.
Can J Surg ; 43(2): 105-11, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10812344

ABSTRACT

OBJECTIVES: To assess patient waiting times for vascular surgery and to determine if complications of the disease develop while the patients are awaiting surgery. DESIGN: Prospective cohort study. SETTING: A university-affiliated tertiary care institution. PATIENTS: All 554 patients who underwent scheduled vascular surgical procedures between April 1995 and October 1996. OUTCOME MEASURES: A literature review carried out to develop guidelines for acceptable waiting times for surgery associated with various vascular disorders based on their natural history (benchmark target); actual waiting times, defined as the interval from the date each patient was booked for surgery to the date of admission to hospital for the procedure; the proportion of patients admitted within the benchmark targets; and whether prolonged waiting time placed patients at risk for complications of their disease. RESULTS: Of the 554 patients, 382 (69%) were admitted within the benchmark waiting times. Of 84 patients having an abdominal aortic aneurysm, the aneurysm ruptured during the waiting period in 6, and 4 of them died, for a complication rate of 7% and a death rate of 5%. Two of the 6 aneurysms ruptured after the patient had waited longer than the target time. Three of 100 patients with symptomatic carotid artery stenosis awaiting admission for carotid endarterectomy suffered ischemic stroke, for a 3% complication rate; all had waited longer than the target period. One patient suffered occlusion of a femoropopliteal bypass graft while awaiting revision of a stenosed bypass graft. CONCLUSIONS: This study suggests that although most patients are admitted for operation within the benchmark time, one-third are admitted late and may suffer serious complications of their disease while awaiting admission for the procedure.


Subject(s)
Patient Admission/statistics & numerical data , Vascular Diseases/complications , Vascular Diseases/surgery , Vascular Surgical Procedures/statistics & numerical data , Waiting Lists , Aortic Aneurysm, Abdominal/complications , Aortic Aneurysm, Abdominal/surgery , Arteriovenous Shunt, Surgical , Benchmarking , British Columbia/epidemiology , Carotid Stenosis/complications , Carotid Stenosis/surgery , Disease Progression , Health Services Research , Hospitals, University , Humans , Peripheral Vascular Diseases/complications , Peripheral Vascular Diseases/surgery , Practice Guidelines as Topic , Prospective Studies , Risk Factors , Time Factors , Treatment Outcome
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