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1.
SSM Popul Health ; 22: 101412, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37180355

RESUMEN

Self-reported height measures are increasingly being included in large-scale surveys in order to measure BMI. There have been concerns about the validity of self-reported measures but there remains little understanding of why respondents may not give accurate height reports. We examine whether a lack of knowledge could be a contributing factor, by investigating the reliability of self-reported height over time and across countries. We use longitudinal data from four large-scale longitudinal surveys conducted in Australia, United States, United Kingdom, and Europe (14 countries) where survey respondents were asked to report their height over multiple time periods to measure the extent of consistency of height reports across time. The overall level of inconsistent reporting of height is largest in Australia and Europe. Individuals with lower levels of education were significantly more likely to give two height reports that differed by 5 cm or more. Across all countries, inconsistent reporting with large height differences between waves was also more common among those in older populations. The findings point to subgroups of the population exhibiting a lack of knowledge regarding their own height.

2.
Health Soc Care Community ; 30(6): e5083-e5094, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35915919

RESUMEN

Lifeline Australia operates crisis support services through Lifeline Crisis Supporters. An integral part of their role is to conduct online suicide risk assessments with help-seekers. However, there is limited literature regarding suicide risk assessment practices for this population. This study aimed to examine how suicide prevention training, vicarious trauma and fears impacted suicide risk assessment behaviours of Lifeline Crisis Supporters. A cross-sectional survey design was used to recruit a volunteer convenience sample of 125 Lifeline Australia Crisis Supporters (75.2% females; Mage  = 54.9) in 2018 to participate in an online survey. Findings revealed that those with more suicide-specific training had less risk assessment-related fears, and that fears were not related to attitudes towards suicide prevention. There was no significant relationship between vicarious trauma and amount of training or years of experience in the role. Further, participants with higher levels of vicarious trauma demonstrated significantly more negative attitudes towards suicide prevention. Overall, training appears to be a significant factor in suicide risk assessment practice behaviours of Lifeline Crisis Supporters, highlighting a need for ongoing training and support for them. This research also suggests that whilst fears exist, they do not significantly impair Lifeline Crisis Supporters' ability to undertake suicide risk assessment.


Asunto(s)
Desgaste por Empatía , Suicidio , Femenino , Humanos , Persona de Mediana Edad , Masculino , Intervención en la Crisis (Psiquiatría) , Líneas Directas , Estudios Transversales , Medición de Riesgo , Miedo
3.
Soc Sci Med ; 297: 114821, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35219050

RESUMEN

RATIONALE: The effect of COVID-19 lockdowns on mental health is a major concern worldwide. Measuring the impacts, however, is difficult because of a lack of data that tracks and compares outcomes and potential protective social factors before and during lockdowns. OBJECTIVE: We aim to quantify the impact of a second lockdown in 2020 in the Australian city of Melbourne on levels of depression, anxiety, and loneliness, and analyse whether social relations in the neighbourhood may buffer against the worst effects of lockdown. METHODS: We draw on quasi-experimental data from a nationally-representative longitudinal survey conducted in Australia. We use a difference-in-difference approach with a number of control variables to estimate changes in mental health among respondents in Melbourne following the imposition of the lockdown. A measure of perceived neighbourhood social relations is included as an explanatory variable to analyse potential protective effects. RESULTS: Lockdown is estimated to have increased depressive symptoms by approximately 23% and feelings of loneliness by 4%. No effect on anxiety was detected. Levels of neighbourhood social relations were strongly negatively associated with mental health symptoms. A significant interaction between lockdown and neighbourhood social relations suggests that lockdown increased depressive symptoms by 21% for people with average perceived neighbourhood relations, compared with a 9.7% increase for people whose perceived relations is one standard deviation greater than average. CONCLUSION: The results add to evidence of the harsh impacts of the COVID-19 pandemic and associated lockdowns on mental health. Importantly, neighbourhood social relations and social cohesion more broadly may be an important source of social support in response to lockdowns. These findings provide important insights for researchers and policy-makers in how to understand and respond to the mental health impacts of COVID-19.


Asunto(s)
COVID-19 , Australia/epidemiología , COVID-19/epidemiología , COVID-19/prevención & control , Control de Enfermedades Transmisibles , Humanos , Salud Mental , Pandemias/prevención & control
4.
Hum Reprod ; 34(10): 1906-1914, 2019 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-31560763

RESUMEN

STUDY QUESTION: What is the likelihood of having a child within 4 years for men and women with strong short-term reproductive intentions, and how is it affected by age? SUMMARY ANSWER: For women, the likelihood of realising reproductive intentions decreased steeply from age 35: the effect of age was weak and not significant for men. WHAT IS KNOWN ALREADY: Men and women are postponing childbearing until later ages. For women, this trend is associated with a higher risk that childbearing plans will not be realised due to increased levels of infertility and pregnancy complications. STUDY DESIGN, SIZE, DURATION: This study analyses two waves of the nationally representative Household, Income and Labour Dynamics in Australia (HILDA) survey. The analytical sample interviewed in 2011 included 447 men aged 18-45 and 528 women aged 18-41. These respondents expressed a strong intention to have a child in the next 3 years. We followed them up in 2015 to track whether their reproductive intention was achieved or revised. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: Multinomial logistic regression is used to account for the three possible outcomes: (i) having a child, (ii) not having a child but still intending to have one in the future and (iii) not having a child and no longer intending to have one. We analyse how age, parity, partnership status, education, perceived ability to conceive, self-rated health, BMI and smoking status are related to realising or changing reproductive intentions. MAIN RESULTS AND THE ROLE OF CHANCE: Almost two-thirds of men and women realised their strong short-term fertility plans within 4 years. There was a steep age-related decline in realising reproductive intentions for women in their mid- and late-30s, whereas men maintained a relatively high probability of having the child they intended until age 45. Women aged 38-41 who planned to have a child were the most likely to change their plan within 4 years. The probability of realising reproductive intention was highest for married and highly educated men and women and for those with one child. LIMITATIONS, REASONS FOR CAUTION: Our study cannot separate biological, social and cultural reasons for not realising reproductive intentions. Men and women adjust their intentions in response to their actual circumstances, but also in line with their perceived ability to have a child or under the influence of broader social norms on reproductive age. WIDER IMPLICATIONS OF THE FINDINGS: Our results give a new perspective on the ability of men and women to realise their reproductive plans in the context of childbearing postponement. They confirm the inequality in the individual consequences of delayed reproduction between men and women. They inform medical practitioners and counsellors about the complex biological, social and normative barriers to reproduction among women at higher childbearing ages. STUDY FUNDING/COMPETING INTEREST(S): This research was partly supported by a Research School of Social Sciences Visiting Fellowship at the Australian National University and an Australian Research Council Discovery Project (DP150104248). Éva Beaujouan's work was partly funded by the Austrian Science Fund (FWF) project 'Later Fertility in Europe' (Grant agreement no. P31171-G29). This paper uses unit record data from the HILDA Survey. The HILDA Project was initiated and is funded by the Australian Government Department of Social Services (DSS) and is managed by the Melbourne Institute of Applied Economic and Social Research (Melbourne Institute). The findings and views reported in this paper, however, are those of the authors and should not be attributed to either DSS or the Melbourne Institute. The authors have no conflicts of interest.


Asunto(s)
Envejecimiento/fisiología , Fertilidad/fisiología , Intención , Conducta Reproductiva/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Australia , Escolaridad , Femenino , Humanos , Estudios Longitudinales , Masculino , Estado Civil/estadística & datos numéricos , Persona de Mediana Edad , Paridad , Embarazo , Conducta Reproductiva/fisiología , Conducta Reproductiva/psicología , Encuestas y Cuestionarios/estadística & datos numéricos , Adulto Joven
5.
Demography ; 56(4): 1219-1246, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31290087

RESUMEN

Many studies have found that married people have higher subjective well-being than those who are not married. Yet the increase in cohabitation raises questions as to whether only marriage has beneficial effects. In this study, we examine differences in subjective well-being between cohabiting and married men and women in midlife, comparing the United Kingdom, Australia, Germany, and Norway. We apply propensity score-weighted regression analyses to examine selection processes into marriage and differential treatment bias. We find no differences between cohabitation and marriage for men in the United Kingdom and Norway, and women in Germany. However, we do find significant differences for men in Australia and women in Norway. The differences disappear after we control for selection in Australia, but they unexpectedly persist for Norwegian women, disappearing only when we account for relationship satisfaction. For German men and British and Australian women, those with a lower propensity to marry would benefit from marriage. Controls eliminate differences for German men, although not for U.K. women, but relationship satisfaction reduces differences. Overall, our study indicates that especially after selection and relationship satisfaction are taken into account, differences between marriage and cohabitation disappear in all countries. Marriage does not lead to higher subjective well-being; instead, cohabitation is a symptom of economic and emotional strain.


Asunto(s)
Composición Familiar , Felicidad , Matrimonio/psicología , Adulto , Australia , Comparación Transcultural , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Normas Sociales , Bienestar Social/estadística & datos numéricos , Factores Socioeconómicos
6.
Popul Res Policy Rev ; 37(5): 703-728, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30546176

RESUMEN

Extensive research has found that marriage provides health benefits to individuals, particularly in the U.S. The rise of cohabitation, however, raises questions about whether simply being in an intimate co-residential partnership conveys the same health benefits as marriage. Here, we use OLS regression to compare differences between partnered and unpartnered, and cohabiting and married individuals with respect to self-rated health in mid-life, an understudied part of the lifecourse. We pay particular attention to selection mechanisms arising in childhood and characteristics of the partnership. We compare results in five countries with different social, economic, and policy contexts: the U.S. (NLSY), U.K. (UKHLS), Australia (HILDA), Germany (SOEP), and Norway (GGS). Results show that living with a partner is positively associated with self-rated health in mid-life in all countries, but that controlling for children, prior separation, and current socio-economic status eliminates differences in Germany and Norway. Significant differences between cohabitation and marriage are only evident in the U.S. and the U.K., but controlling for childhood background, union duration, and prior union dissolution eliminates partnership differentials. The findings suggest that cohabitation in the U.S. and U.K., both liberal welfare regimes, seems to be very different than in the other countries. The results challenge the assumption that only marriage is beneficial for health.

7.
Reprod Health ; 15(1): 134, 2018 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-30185179

RESUMEN

BACKGROUND: In Australia, the National Health and Medical Research Council has banned the use of assisted reproductive technology for social sex selection, but notes "there is limited research into the question of whether Australians support the use of sex selection for non-medical purposes". This paper investigates Australian attitudes to sex-selection technology by different means (IVF, abortion, and a hypothetical pill), for different reasons (medical, family balancing, any reason), and by differing respondent characteristics (age, sex, education and religiosity). METHODS: In 2007 and 2016, the Australian Survey of Social Attitudes (AuSSA) collected data on the attitudes of Australian adults to sex selection through IVF, abortion, and a hypothetical pill. We calculate population-weighted distributions and 95% confidence intervals of responses, and carry out logistic regressions to investigate the demographic characteristics of Australians who strongly disapprove of IVF or abortion for sex selection. RESULTS: In 2016, around three-quarters of AuSSA respondents were opposed to legalising sex selection through IVF for any reason, or for family balancing for a second or third child. Thirty-seven per cent were opposed to IVF for medical sex selection. Two-thirds of respondents in both 2007 and 2016 disapproved or strongly disapproved of IVF for sex selection, while the proportion who strongly disapproved increased from 31 to 40%. Disapproval/strong disapproval of abortion for sex selection increased from 74 to 81% from 2007 to 2016, while strong disapproval alone rose from 44 to 55%. More than 70% of respondents in both 2007 and 2016 stated that a hypothetical pill for sex selection should not be legal. Our analysis finds that female, young, more-educated, and more religious respondents are more likely to strongly disapprove of sex selection via IVF or abortion, and that the increase in those who strongly disapprove from 2007 to 2016 is statistically significant. CONCLUSIONS: Australians generally disapprove of the use of sex-selection technology. If legislation is to be guided by community attitudes, then the prohibition against sex selection for non-medical purposes through assisted reproductive technology should be maintained.


Asunto(s)
Aborto Inducido , Actitud Frente a la Salud , Técnicas Reproductivas Asistidas/psicología , Preselección del Sexo/psicología , Adolescente , Adulto , Australia , Niño , Femenino , Humanos , Masculino , Embarazo
9.
J Burn Care Res ; 38(2): 90-98, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28045780

RESUMEN

The effects of burn injury on cardiovascular responsiveness to vasoactive agents are not well understood. The aims of this study were to determine whether burn injury alters cardiovascular reactivity to vasoactive drugs in vivo and intrinsic function of isolated mesenteric resistance arteries. Anesthetized Sprague-Dawley rats were subjected to sham procedure or 30% TBSA dorsal scald burn, followed by crystalloid resuscitation (Parkland Formula). At 24, 72, 96, and 168 hours post burn, rats were reanesthetized, and the mean arterial blood pressure (MAP) responses to various doses of the α1-adrenergic receptor agonist phenylephrine and arginine vasopressin were tested. Mesenteric arteries were harvested from uninjured animals and at 24 and 168 hours post burn. The responsiveness of arteries to phenylephrine and arginine vasopressin was tested by pressure myography. Dose response curves were generated and EC50 concentrations, Hill slopes, and maximal effects were compared. The potency of phenylephrine to increase MAP was reduced 2-fold 24 hours post burn (P < .05 vs sham) and gradually normalized at later time points. The reactivity of isolated arteries to phenylephrine was not significantly altered after burns. The potency of arginine vasopressin to increase MAP and to constrict isolated arteries was increased 2- to 3-fold at 24 hours post burn (P < .05) and normalized at later time points. Our findings suggest that burn injury differentially regulates vasopressor and blood pressure effects of α-adrenergic and vasopressin receptor agonists. Intrinsic vasopressin receptor reactivity of resistance arteries is sensitized early after burns. These findings will help to optimize resuscitation strategies and vasopressor use in difficult to resuscitate burn patients.


Asunto(s)
Antagonistas de Receptores Adrenérgicos alfa 1/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Quemaduras/complicaciones , Sistema Cardiovascular/efectos de los fármacos , Resucitación/métodos , Vasopresinas/administración & dosificación , Animales , Quemaduras/terapia , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Inyecciones Intravenosas , Masculino , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Resultado del Tratamiento , Resistencia Vascular/efectos de los fármacos
10.
J Burn Care Res ; 38(1): e133-e143, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-26204385

RESUMEN

The objective of this study was to determine whether urine ubiquitin levels are elevated after burns and to assess whether urine ubiquitin could be useful as a noninvasive biomarker for burn patients. Forty burn patients (%TBSA: 20 ± 22; modified Baux scores: 73 ± 26) were included (control: 11 volunteers). Urine was collected in 2-hour intervals for 72 hours, followed by 12-hour intervals until discharge from the intensive care unit. Ubiquitin concentrations were analyzed by enzyme linked immunosorbent assay and Western blot. Total protein was determined with a Bradford assay. Patient characteristics and clinical parameters were documented. Urine ubiquitin concentrations, renal ubiquitin excretion, and excretion rates were correlated with patient characteristics and outcomes. Initial urine ubiquitin concentrations were 362 ± 575 ng/ml in patients and 14 ± 18 ng/ml in volunteers (P < .01). Renal ubiquitin excretion on day 1 was 292.6 ± 510.8 µg/24 hr and 21 ± 27 µg/24 hr in volunteers (P < .01). Initial ubiquitin concentrations correlated with modified Baux scores (r = .46; P = .02). Ubiquitin levels peaked at day 6 postburn, whereas total protein concentrations and serum creatinine levels remained within the normal range. Total renal ubiquitin excretion and excretion rates were higher in patients with %TBSA ≥20 than with %TBSA <20, in patients who developed sepsis/multiple organ failure than in patients without these complications and in nonsurvivors vs survivors. These data suggest that ubiquitin urine levels are significantly increased after burns. Renal ubiquitin excretion and/or excretion rates are associated with %TBSA, sepsis/multiple organ failure, and mortality. Although these findings may explain previous correlations between systemic ubiquitin levels and outcomes after burns, the large variability of ubiquitin urine levels suggests that urine ubiquitin will not be useful as a noninvasive disease biomarker.


Asunto(s)
Quemaduras/mortalidad , Quemaduras/orina , Ubiquitina/orina , Adulto , Anciano , Biomarcadores/análisis , Western Blotting , Superficie Corporal , Quemaduras/diagnóstico , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Valores de Referencia , Tasa de Supervivencia
11.
Surgery ; 160(4): 839-849, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27524432

RESUMEN

BACKGROUND: Our objective was to determine the hospital resources required for low-volume, high-quality care at high-volume cancer resection centers. METHODS: Patients who underwent esophageal, pancreatic, and rectal resection for malignancy were identified using Healthcare Cost and Utilization Project State Inpatient Database (Florida and California) between 2007 and 2011. Annual case volume by procedure was used to identify high- and low-volume centers. Hospital data were obtained from the American Hospital Association Annual Survey Database. Procedure risk-adjusted mortality was calculated for each hospital using multilevel, mixed-effects models. RESULTS: A total of 24,784 patients from 302 hospitals met the inclusion criteria. Of these, 13 hospitals were classified as having a high-volume, oncologic resection ecosystem by being a high-volume hospital for ≥2 studied procedures. A total of 11 of 31 studied hospital factors were strongly associated with hospitals that performed a high volume of cancer resections and were used to develop the High Volume Ecosystem for Oncologic Resections (HIVE-OR) score. At low-volume centers, increasing HIVE-OR score resulted in decreased mortality for rectal cancer resection (P = .038). HIVE-OR was not related to risk-adjusted mortality for esophagectomy (P = .421) or pancreatectomy (P = .413) at low-volume centers. CONCLUSION: Our study found that in some settings, low-volume, high-quality cancer surgical care can be explained by having a high-volume ecosystem.


Asunto(s)
Colectomía/mortalidad , Esofagectomía/mortalidad , Mortalidad Hospitalaria/tendencias , Hospitales de Alto Volumen , Pancreatectomía/mortalidad , Calidad de la Atención de Salud , Anciano , Colectomía/métodos , Bases de Datos Factuales , Ecosistema , Esofagectomía/métodos , Femenino , Encuestas de Atención de la Salud , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Pancreatectomía/métodos , Rol , Análisis de Supervivencia , Estados Unidos
12.
Int J Mol Sci ; 17(5)2016 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-27331810

RESUMEN

Recent evidence suggests that C-X-C chemokine receptor type 4 (CXCR4) heteromerizes with α1A/B-adrenoceptors (AR) and atypical chemokine receptor 3 (ACKR3) and that CXCR4:α1A/B-AR heteromers are important for α1-AR function in vascular smooth muscle cells (VSMC). Structural determinants for CXCR4 heteromerization and functional consequences of CXCR4:α1A/B-AR heteromerization in intact arteries, however, remain unknown. Utilizing proximity ligation assays (PLA) to visualize receptor interactions in VSMC, we show that peptide analogs of transmembrane-domain (TM) 2 and TM4 of CXCR4 selectively reduce PLA signals for CXCR4:α1A-AR and CXCR4:ACKR3 interactions, respectively. While both peptides inhibit CXCL12-induced chemotaxis, only the TM2 peptide inhibits phenylephrine-induced Ca(2+)-fluxes, contraction of VSMC and reduces efficacy of phenylephrine to constrict isolated arteries. In a Cre-loxP mouse model to delete CXCR4 in VSMC, we observed 60% knockdown of CXCR4. PLA signals for CXCR4:α1A/B-AR and CXCR4:ACKR3 interactions in VSMC, however, remained constant. Our observations point towards TM2/4 of CXCR4 as possible contact sites for heteromerization and suggest that TM-derived peptide analogs permit selective targeting of CXCR4 heteromers. A molecular dynamics simulation of a receptor complex in which the CXCR4 homodimer interacts with α1A-AR via TM2 and with ACKR3 via TM4 is presented. Our findings further imply that CXCR4:α1A-AR heteromers are important for intrinsic α1-AR function in intact arteries and provide initial and unexpected insights into the regulation of CXCR4 heteromerization in VSMC.


Asunto(s)
Músculo Liso Vascular/metabolismo , Multimerización de Proteína , Receptores Adrenérgicos alfa 1/metabolismo , Receptores CXCR4/metabolismo , Animales , Sitios de Unión , Calcio/metabolismo , Línea Celular , Células Cultivadas , Femenino , Humanos , Masculino , Ratones , Simulación de Dinámica Molecular , Unión Proteica , Ratas , Ratas Sprague-Dawley , Receptores CXCR/genética , Receptores CXCR/metabolismo , Receptores CXCR4/química , Receptores CXCR4/genética
13.
Infect Control Hosp Epidemiol ; 37(8): 916-923, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27277136

RESUMEN

OBJECTIVE To evaluate time to clinical response before and after implementation of rapid blood culture identification technologies. DESIGN Before-and-after trial. SETTING Large, tertiary, urban, academic health-sciences center. PATIENTS Patients >18 years old with sepsis and concurrent bacteremia or fungemia were included in the study; patients who were pregnant, had polymicrobial septicemia, or were transferred from an outside hospital were excluded. INTERVENTION Prior to the intervention, polymerase chain reaction was used to identify Staphylococcus species from positive blood cultures, and traditional laboratory techniques were used to identify non-staphylococcal species. After the intervention, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) assay and FilmArray were also used to identify additional species. During both periods, the antimicrobial stewardship team provided prospective audit and feedback for all patients on antibiotics. RESULTS A total of 219 patients were enrolled in the study: 115 patients prior to the intervention and 104 after the intervention. The median time to clinical response was statistically significantly shorter in the postintervention group than in the preintervention group (2 days vs 4 days, respectively; P=.002). By Cox regression, the implementation of MALDI-TOF and FilmArray was associated with shorter time to clinical response (hazard ratio [HR], 1.360; 95% confidence interval [CI], 1.018-1.816). After controlling for potential confounders, the study group was not independently associated with clinical response (adjusted HR, 1.279; 95% CI, 0.955-1.713). Mortality was numerically, but not statistically significantly, lower in the postintervention group than in the preintervention group (7.6% vs 11.4%; P=.342). CONCLUSIONS In the setting of an existing antimicrobial stewardship program, implementation of MALDI-TOF and FilmArray was associated with improved time to clinical response. Further research is needed to fully describe the effect of antimicrobial stewardship programs on time to clinical response. Infect Control Hosp Epidemiol 2016;37:916-923.


Asunto(s)
Cultivo de Sangre/métodos , Sepsis/diagnóstico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Centros Médicos Académicos , Anciano , Algoritmos , Antibacterianos/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Sepsis/tratamiento farmacológico , Factores de Tiempo
14.
Am J Bot ; 103(3): 553-67, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26872491

RESUMEN

PREMISE OF THE STUDY: Whenever more pollen grains arrive on stigmas than necessary to fertilize ovules, sexual selection is possible. However, the role of sexual selection remains controversial, in part because of lack of evidence on genetic bases of traits and the response of relevant characters to selection. METHODS: In an experiment with Raphanus sativus, we selected on tendency to sire seeds in the stylar or basal regions of fruits. This character is likely related to pollen tube growth rate, and seed position affects rates of abortion and seed predation. We measured differences among families in seed siring and related characters and evaluated responses to selection. KEY RESULTS: All replicates showed strong effects of pollen donor family on proportion of seeds sired per fruit in mixed pollinations. Most also showed effects of pollen donor family on number of pollen grains per flower and pollen diameter. Two of four replicates showed a response to selection on position of seeds sired. In responding replicates, we found trade-offs in pollen grain size and number; plants with larger pollen grains sired more seeds in the basal region. CONCLUSIONS: Our data suggest a genetic basis for pollen donor ability to sire seeds in competition. The significant response to selection in two replicates shows that position of seeds sired can respond to selection. Thus, all components for sexual selection to occur and affect traits are present. Variation in results among replicates might be due to changes in greenhouse conditions. Environmental effects may contribute to the maintenance of variation in these fitness-related characters.


Asunto(s)
Evolución Biológica , Raphanus/fisiología , Selección Genética , Análisis de Varianza , Distribución de Chi-Cuadrado , Modelos Biológicos , Polen/fisiología , Polinización , Semillas/fisiología
15.
Dis Colon Rectum ; 57(8): 983-92, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25003293

RESUMEN

BACKGROUND: Quality of publications is considered a subjective measurement, and more weight is placed on prospective studies, especially randomized clinical trials and meta-analyses. OBJECTIVE: This study describes the type of publications and evaluates the quality of randomized clinical trials and review articles using an objective measurement. DATA SOURCES: Medline (PubMed) is the data source for this work. STUDY SELECTION: We used the terms "rectal neoplasms/surgery" and the filters "10 years," "humans," and "English." MAIN OUTCOME MEASURES: We measured compliance with checklist items. Randomized clinical trials were reviewed using the Consolidates Standards of Reporting Trials statement; systematic reviews/meta-analyses were reviewed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. RESULTS: A total of 3603 articles were identified: 20.8% were case report/series, 20.5% were retrospective cohorts, 14.0% were reviews or meta-analyses, 16.4% were prospective cohorts, 14.0% were other types of articles (comments, letters, or editorials), 5.5% were clinical trials (phase I/II), 4.2% were randomized clinical trials, and 4.4% were cross-sectional studies. We reviewed 108 randomized clinical trials; the maximum score possible was 74.0, the average score was 44.6 (range, 20.0-64.0), 4 (3.7%) were graded as "excellent," 21 (19.4%) were "good," 44 (40.7%) were "deficient," and 39 (36.1%) were graded as "fail." The predictors of higher scores for randomized clinical trials were year of publication after 2007 (p = 0.00), higher impact factor (p = 0.03), and declared funding (p = 0.01). Twenty-nine meta-analyses were reviewed; the average score was 19.64 (range, 12.0-25.0); 5 articles (17.2%) were graded as "excellent," 12 (41.4%) were "good," 10 (34.5%) were "deficient," and 2 (6.9%) were "fail." LIMITATIONS: Only 1 electronic database was used, so we lacked a validated score. In addition, the search terms did not include "colorectal." CONCLUSIONS: A total of 20.8% of the articles published were case reports and 25.0% of the articles were prospective or clinical trials. Although randomized clinical trials and systematic reviews provide the highest level of evidence, publications with missing data limit replication of the study and affect the generalizability of results to other populations. To improve the quality of our publications, authors, reviewers, and journal editors should consider the endorsement of standardize checklists.


Asunto(s)
Bibliometría , Publicaciones Periódicas como Asunto , Edición/estadística & datos numéricos , Neoplasias del Recto/cirugía , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación
16.
Demography ; 51(2): 485-508, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24399143

RESUMEN

This article compares mothers' experience of having children with more than one partner in two liberal welfare regimes (the United States and Australia) and two social democratic regimes (Sweden and Norway). We use survey-based union and birth histories in Australia and the United States and data from national population registers in Norway and Sweden to estimate the likelihood of experiencing childbearing across partnerships at any point in the childbearing career. We find that births with new partners constitute a substantial proportion of all births in each country we study. Despite quite different arrangements for social welfare, the determinants of childbearing across partnerships are very similar. Women who had their first birth at a very young age or who are less well-educated are most likely to have children with different partners. The educational gradient in childbearing across partnerships is also consistently negative across countries, particularly in contrast to educational gradients in childbearing with the same partner. The risk of childbearing across partnerships increased dramatically in all countries from the 1980s to the 2000s, and educational differences also increased, again, in both liberal and social democratic welfare regimes.


Asunto(s)
Composición Familiar , Madres/psicología , Parejas Sexuales , Adolescente , Adulto , Australia , Femenino , Humanos , Funciones de Verosimilitud , Noruega , Encuestas y Cuestionarios , Suecia , Estados Unidos , Adulto Joven
19.
Adv Life Course Res ; 18(2): 141-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24796265

RESUMEN

This paper examines the concept of desired future fertility. Childbearing desires are often conceptualized in the literature as representing an individual's ideal future fertility where there are no constraints or obstacles to achieve the desired outcome. As such, childbearing desires, unlike fertility intentions, are thought to be relatively unaffected by changing life circumstances. Using a theoretically driven model incorporating goal adjustment, we test whether desires of childless men and women do in fact change over time. Using data from the Household, Income and Labour Dynamics in Australia (HILDA) survey (2001-2010) we specifically investigate whether changing life circumstances do effect a change in childbearing desires. We find that age is strongly related to adjusting childbearing desires, as is relationship formation. Desires are however, not greatly influenced by short-term shocks such as an episode of poor health or unemployment, although these events have different effects for women and for men. Overall, the findings are consistent with psychological theories of goal adjustment, that is, individuals will revise their desires for having children if they perceive that their desires are not likely to be fulfilled.


Asunto(s)
Composición Familiar , Objetivos , Intención , Acontecimientos que Cambian la Vida , Adolescente , Adulto , Factores de Edad , Australia , Estudios Transversales , Femenino , Humanos , Renta , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Teoría Psicológica , Adulto Joven
20.
J Antimicrob Chemother ; 66(7): 1600-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21508008

RESUMEN

OBJECTIVES: Despite the increasing incidence of carbapenem-intermediate or -resistant Enterobacteriaceae (CIRE), risk factors associated with CIRE infections have not been well defined. This study characterizes factors associated with CIRE among two different source populations. METHODS: A case-control study was performed at a tertiary care medical centre between January 2005 and December 2009. Cases were adults with a culture-confirmed Enterobacteriaceae infection with reduced susceptibility to meropenem or ertapenem. The CIRE cases were matched 1:1 to patients from two different control series: (i) those with carbapenem-susceptible Enterobacteriaceae (CSE) infections; and (ii) inpatients residing on the same ward within 30 days of CIRE culture date. Logistic regression was used to identify variables independently associated with CIRE among each source population. Restricted multivariate analyses were performed to determine if covariates predictive of CIRE varied by infecting organism or presence of the bla(KPC) gene. RESULTS: There were 102 cases of CIRE during the study period. The only covariate independently associated with CIRE in all multivariate analyses was the cumulative number of prior antibiotic exposures. Compared with CSE controls, the odds ratios (95% confidence interval) were 1.43 (1.19-1.72), 2.05 (1.70-2.47) and 2.93 (2.43-3.53) for 1, 2 and ≥ 3 antibiotic exposures, respectively. The strength of this association was comparable for the hospitalized control group and analyses stratified by organism and presence of the bla(KPC) gene. CONCLUSIONS: A patient's cumulative antibiotic exposure history is likely to be more important than any one specific exposure when determining the likelihood of developing a CIRE infection.


Asunto(s)
Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Infecciones por Enterobacteriaceae/epidemiología , Enterobacteriaceae/efectos de los fármacos , Resistencia betalactámica , Centros Médicos Académicos , Adulto , Anciano , Estudios de Casos y Controles , Utilización de Medicamentos/estadística & datos numéricos , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/microbiología , Ertapenem , Femenino , Humanos , Masculino , Meropenem , Persona de Mediana Edad , Factores de Riesgo , Tienamicinas/farmacología , Tienamicinas/uso terapéutico , beta-Lactamas/farmacología , beta-Lactamas/uso terapéutico
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