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1.
Taller individuals have on average a higher socio-economic status than shorter individuals. In countries where entrepreneurs have high social status, we may therefore expect that entrepreneurs are taller than wage workers. Using data from the German Socio-Economic Panel (2002–2012), we find that a 1 cm increase in an individual's height raises the probability of being self-employed (the most common proxy for entrepreneurship) versus paid employed by 0.15 percentage points. Within the self-employed, the probability of being an employer is increased by 0.10 percentage points as a result of a 1 cm increase in height, whereas this increase is 0.05 percentage points for an own-account worker. This result corroborates the higher social status of employers compared to own-account workers. We find a height premium in earnings for self-employed and paid-employed individuals: an additional 1 cm in height is associated with a 0.39% increase in hourly earnings for paid employees and a 0.52% increase for self-employed individuals. Our analysis reveals that approximately one third of the height premium in earnings is explained by differences in educational attainment. We also establish the existence of a height premium in terms of work and life satisfaction, which is more pronounced for paid employees than for self-employed individuals.  相似文献   

2.
We use the Young Finns Study (N = ∼2000) on the measured height linked to register-based long-term labor market outcomes. The data contain six age cohorts (ages 3, 6, 9, 12, 15 and 18, in 1980) with the average age of 31.7, in 2001, and with the female share of 54.7. We find that taller people earn higher earnings according to the ordinary least squares (OLS) estimation. The OLS models show that 10 cm of extra height is associated with 13% higher earnings. We use Mendelian randomization, with the genetic score as an instrumental variable (IV) for height to account for potential confounders that are related to socioeconomic background, early life conditions and parental investments, which are otherwise very difficult to fully account for when using covariates in observational studies. The IV point estimate is much lower and not statistically significant, suggesting that the OLS estimation provides an upward biased estimate for the height premium. Our results show the potential value of using genetic information to gain new insights into the determinants of long-term labor market success.  相似文献   

3.
It is not currently known how the mechanical properties of human tendons change with maturation in the two sexes. To address this, the stiffness and Young's modulus of the patellar tendon were measured in men, women, boys and girls (each group, n=10). Patellar tendon force (Fpt) was calculated from the measured joint moment during a ramped voluntary isometric knee extension contraction, the antagonist knee extensor muscle co-activation quantified from its electromyographical activity, and the patellar tendon moment arm measured from magnetic resonance images. Tendon elongation was imaged using the sagittal-plane ultrasound scans throughout the contraction. Tendon cross-sectional area was measured at rest from ultrasound scans in the transverse plane. Maximal Fpt and tendon elongation were (mean±SE) 5453±307 N and 5±0.5 mm for men, 3877±307 N and 4.9±0.6 mm for women, 2017±170 N and 6.2±0.5 mm for boys and 2169±182 N and 5.9±0.7 mm for girls. In all groups, tendon stiffness and Young's modulus were examined at the level that corresponded to the maximal 30% of the weakest participant's Fpt and stress, respectively; these were 925–1321 N and 11.5–16.5 MPa, respectively. Stiffness was 94% greater in men than boys and 84% greater in women than girls (p<0.01), with no differences between men and women, or boys and girls (men 1076±87 N/mm; women 1030±139 N/mm; boys 555±71 N/mm and girls 561.5±57.4 N/mm). Young's modulus was 99% greater in men than boys (p<0.01), and 66% greater in women than girls (p<0.05). There were no differences in modulus between men and women, or boys and girls (men 597±49 MPa; women 549±70 MPa; boys 255±42 MPa and girls 302±33 MPa). These findings indicate that the mechanical stiffness of tendon increases with maturation due to an increased Young's modulus and, in females due to a greater increase in tendon cross-sectional area than tendon length.  相似文献   

4.
5.
Declining male fertility has prompted investigations into the diagnostic methods that would permit frequent, non-invasive and accurate detection of changes in testicular histomorphology and the reproductive status of individuals. Ultrasonographic (U/S) and magnetic resonance (MR) imaging both have the potential to be used in this manner as associations have previously been described between the U/S and MR image attributes and histopathological changes in testicular tissue. The present study set out to determine if correlations exist between quantitative U/S and MR image attributes and histomorphological characteristics (total and luminal seminiferous tubule, ST area, and parenchymal cell density) of the excised ram testes, and to compare relative sensitivities of the imaging techniques. The echotextural/MR (input variables) and histological parameters (output variables) were analyzed by the Pearson's product moment correlations. Significant correlations were found for all imaging modalities, with the strongest overall correlation recorded for the T2 FAST SPIN ECHO (T2FSE) MR series (between mean numerical pixel values (NPVs) and total ST area; r = ?0.93, p < 0.001). The greatest number of significant correlations among quantitative image characteristics and histological attributes of testicular tissue were found for the 3 PLANE LOCALIZER (3 PLANE LOC) MR series, followed by the T2FSE MR, 3D FAST-SPOILED GRADIENT ECHO (3D FSPGRE) MR, U/S (7.5 MHz) imaging, and finally T1 SPIN ECHO (T1SE) MR series. No significant correlations were recorded between the quantitative attributes of T1SE images and ST lumen area or parenchymal cell density, or between the attributes of the 3D FSPGRE images and cell density. We concluded that there existed a potential practical application for both U/S and MR image techniques, combined with computer-assisted image analysis, to monitor the changes in testicular histomorphology and male reproductive health and fertility. Scrotal U/S remains a first-line imaging technique for the assessment of male reproductive health due mainly to its versatility and lower cost.  相似文献   

6.
BackgroundWomen with a false-positive result after a screening mammogram have an increased risk of cancer detection in subsequent participations, especially after assessments involving cytology or biopsy. We aimed to compare women's personal characteristics, tumoral features and the radiological appearance of cancers with and without a previous false-positive result generated by additional imaging or invasive procedures.MethodsFrom 1996 to 2007, 111,098 women aged 45–69 years participated in four population-based breast cancer screening programs in Spain, and 1281 cancers were detected. We included all cancers detected in subsequent screenings (n = 703) and explored the occurrence of previous false-positive results. We identified false-positives requiring additional imaging or invasive procedures. Differences on tumoral features (invasiveness, tumor size, and lymph node status) and radiological appearance were assessed by Chi-square test, and agreement between the location of cancer and prior suspicious by Cohen's kappa coefficient. A multivariate analysis was preformed to evaluate the effect of previous screening results and age on the odds of presenting an in situ carcinoma.ResultsAmong the 703 cancers detected in subsequent screenings, 148 women (21.1%) had a previous false-positive result. Of these, 105 were by additional imaging and 43 by invasive procedures. Women with prior false-positive result requiring invasive assessment, compared to women with negative tests, and women with prior false-positive requiring additional imaging, had a higher proportion of in situ carcinomas (31.7%, 15.3%, 12.9%, respectively; p = 0.014) and microcalcifications (37.2%, 20.2%, 9.5%, respectively; p = 0.003). The proportion of in situ carcinomas was even higher in women over 60 years (39.2%, 12.5%, 13.0%, respectively; p = 0.001). Ipsilateral cancer was observed in 65.7% of cases with prior cytology or biopsy (k = 0.479; 95%CI: 0.330–0.794).ConclusionA large number of in situ malignancies and calcification patterns were found among women with prior false-positive result in mammography screening requiring cytology or biopsies, suggesting progression from a previously benign lesion.  相似文献   

7.
It has been proposed that women's preferences for male facial sexual dimorphism are positively correlated with conception probability and differ between short- and long-term mating contexts. In this study, we tested this assumption by analyzing relationships between estradiol levels to the women's preferences of male faces that were manipulated to vary in masculinity. Estradiol was measured in daily saliva samples throughout the entire menstrual cycle collected by Polish women with regular menstrual cycles. In our analyses, we included the three most commonly used definitions of the fertile window in the literature. After computing the overall masculinity preference of each participant and measuring hormone levels, we found that i) the timing of ovulation varied greatly among women (between − 11 and − 17 days from the onset of the next menses, counting backwards), ii) there was no relationship between daily, measured during the day of the test (N = 83) or average for the cycle (N = 115) estradiol levels and masculinity preferences, iii) there were no differences in masculinity preferences between women in low- and high-conception probability phases of the cycle, and iv) there were no differences in masculinity preferences between short- and long-term mating contexts. Our results do not support the idea that women's preferences for a potential sexual partner's facial masculinity fluctuate throughout the cycle.  相似文献   

8.
IntroductionBasal cell carcinoma (BCC) is the most common malignancy in the US. Body mass index (BMI) and height have been associated with a variety of cancer types, yet the evidence regarding BCC is limited. Therefore, we evaluated BMI and height in relation to early-onset BCC (under age 40) and explored the potential role of ultraviolet (UV) radiation exposure and estrogen-related exposures in the BMI-BCC relationship.MethodsBCC cases (n = 377) were identified through a central dermatopathology facility in Connecticut. Control subjects (n = 389) with benign skin conditions were randomly sampled from the same database and frequency matched to cases on age (median = 36, interquartile range 33–39), gender, and biopsy site. Participants reported weight (usual adult and at age 18), adult height, sociodemographic, phenotypic, and medical characteristics, and prior UV exposures. We calculated multivariate odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression models.ResultsAdult BMI was inversely associated with early-onset BCC (obese vs. normal OR = 0.43, 95% CI = 0.26–0.71). A similar inverse association was present for BMI at age 18 (OR = 0.54, 95% CI = 0.34–0.85). Excluding UV exposures from the BMI models and including estrogen-related exposures among women only did not alter the association between BMI and BCC, indicating limited mediation or confounding. We did not observe an association between adult height and BCC (OR per cm = 1.00, 95% CI = 0.98–1.02).ConclusionsWe found a significant inverse association between BMI and early-onset BCC, but no association between height and BCC. This association was not explained by UV exposures or estrogen-related exposures in women.  相似文献   

9.
The 100 m is the blue ribboned event of world athletics competitions, with the winner crowned as the fastest human on Earth. Currently that fastest human is Usain Bolt, who covers 100 m in 9.58 s, achieving an average velocity of 10.43 m s?1. Bolt is a phenomenal athlete, but what is his trick? Using Hills model, relating muscle force and heat liberation to shortening velocity, we propose that Bolt is at an advantage in relative power development and biomechanical efficiency compared to his contemporaries.  相似文献   

10.
Background: Observational studies have associated metformin use with lower colorectal cancer (CRC) incidence but few studies have examined metformin's influence on CRC survival. We examined the relationships among metformin use, diabetes, and survival in postmenopausal women with CRC in the Women's Health Initiative (WHI) clinical trials and observational study. Methods: 2066 postmenopausal women with CRC were followed for a median of 4.1 years, with 589 deaths after CRC diagnosis from all causes and 414 deaths directly attributed to CRC. CRC-specific survival was compared among women with diabetes with metformin use (n = 84); women with diabetes with no metformin use (n = 128); and women without diabetes (n = 1854). Cox proportional hazard models were used to estimate associations among metformin use, diabetes and survival after CRC. Strategies to adjust for potential confounders included: multivariate adjustment with known predictors of colorectal cancer survival and construction of a propensity score for the likelihood of receiving metformin, with model stratification by propensity score quintile. Results: After adjusting for age and stage, CRC specific survival in women with diabetes with metformin use was not significantly different compared to that in women with diabetes with no metformin use (HR 0.75; 95% CI 0.40–1.38, p = 0.67) and to women without diabetes (HR 1.00; 95% CI 0.61–1.66, p = 0.99). Following propensity score adjustment, the HR for CRC-specific survival in women with diabetes with metformin use compared to non-users was 0.78 (95% CI 0.38–1.55, p = 0.47) and for overall survival was 0.86 (95% CI 0.49–1.52; p = 0.60). Conclusions: In postmenopausal women with CRC and DM, no statistically significant difference was seen in CRC specific survival in those who used metformin compared to non-users. Analyses in larger populations of colorectal cancer patients are warranted.  相似文献   

11.
《Cancer epidemiology》2014,38(4):357-363
BackgroundEpidemiological studies on anthropometric features and cutaneous melanoma risk in women yielded inconsistent results, with few analyses involving prospective cohort data. Our objective was to explore several anthropometric characteristics in relation to the risk of melanoma in women.MethodsWe prospectively analysed data from E3N, a French cohort involving 98,995 women born in 1925–1950. Participants completed self-administered questionnaires sent biennially over 1990–2008. Relative risks (RRs) and 95% confidence intervals (CIs) were computed using Cox proportional hazards regression models, adjusted for age, number of naevi, freckling, skin and hair colour, skin sensitivity to sun exposure, residential sun exposure, and physical activity.ResultsHeight was positively associated with melanoma in age-adjusted models only (RR = 1.27, 95% CI = 1.05–1.55 for ≥164 cm vs. <160 cm; P for trend = 0.02). After full adjustment, there was a significantly positive relationship between sitting-to-standing height ratio and melanoma risk (RR = 1.40, 95% CI = 1.06–1.86 for ≥0.533 vs. <0.518; P for trend = 0.02). A large body shape at menarche was inversely associated with the risk of melanoma (RR = 0.78, 95% CI = 0.62–0.98; compared with lean). However, weight, body mass index, body surface area, waist or hip circumference, sitting height or leg length were not significantly associated with risk.ConclusionThese results suggest that height, sitting-to-standing height ratio and body shape at menarche may be associated with melanoma risk. Further research is required to confirm these relationships and better understand the underlying mechanisms.  相似文献   

12.
《Harmful algae》2008,7(6):837-848
The study proposes methodological developments to optimize sampling strategy of resting cysts of Alexandrium catenella to estimate their abundance with a predefined error. This work also aims to provide information on spatial distribution of resting cysts in sediments. The distribution mode of A. catenella resting cysts related to the abundance variability was studied through sediment cores sampling on four different spatial scales and using Ludox CLX gradient density method. The quantification method underestimates by a factor of 2 the resting cysts abundance in one gram of sediment. Application of Taylor's power law allowed us to define a compromise between sampling effort and abundance estimation error. In the case of A. catenella resting cysts from Thau lagoon, the optimal sampling strategy consists of sampling 10 stations on a surface of 2 km2 for a given coefficient of variability (C) of 15%, sampling 3 sediment cores at each station (C = 30%) and counting only one replicate by core (C = 18%). Results related to the application of Taylor's power law are closely dependent on resting cyst density and aggregation in a given sediment. In our area, A. catenella resting cysts are mainly observed in the upper 3 cm of sediment. Horizontally, their heterogeneity is lower on 10 cm2 surface and tends to stabilize itself beyond a surface of 10 m2. Each author has to carry out this pre-sampling effort for his own resting cysts-forming species, in his own area, in order to increase accuracy of resting cyst mapping.  相似文献   

13.
Background: We investigated the magnitude of educational differences in lung and upper aero digestive tract (UADT) cancer mortality in France from 1990 to 2007. Methods: The analyses were based on census data from a representative sample of the French population. Educational level was used as the indicator for socioeconomic status. Educational differences in mortality from lung and UADT cancer were calculated among people aged 30–74 and by birth cohort. Two periods were compared: 1990–1998 and 1999–2007. Mortality rates, hazard ratios and relative indices of inequality (RII) were computed. Results: We found higher lung and UADT cancer mortality among those with less education. Inequalities in male UADT cancer mortality remained stable over time (RII1990–1998 = 0.21 (95% confidence interval 0.15–0.29); RII1999–2007 = 0.17 (0.11–0.26)) whereas inequalities in lung cancer mortality increased among the younger men (RII1990–1998 = 0.48 (0.28–0.83); RII1999–2007 = 0.16 (0.09–0.31)). Among women, inequalities in lung cancer mortality became apparent during the second period with higher mortality among those with less education. This trend was exclusively driven by the younger women, among whom inequalities reached about the same magnitude as among younger men (RII1999–2007 = 0.21 (0.08–0.56)). Conclusion: UADT cancer mortality rates strongly decreased over time for every educational level. This implies that the burden of health associated with socioeconomic inequalities in UADT cancer mortality decreased substantially. Inequalities in lung cancer mortality are increasing among the younger generation and are expected to increase even more. Differences in magnitude of inequalities among men and women may disappear in the coming decades.  相似文献   

14.
Anger-prone individuals are volatile and frequently dangerous. Accordingly, inferring the presence of this personality trait in others was important in ancestral human populations. This inference, made under uncertainty, can result in two types of errors: underestimation or overestimation of trait anger. Averaged over evolutionary time, underestimation will have been the more costly error, as the fitness decrements resulting from physical harm or death due to insufficient vigilance are greater than those resulting from lost social opportunities due to excessive caution. We therefore hypothesized that selection has favored an upwards bias in the estimation of others' trait anger relative to estimations of other traits not characterized by such an error asymmetry. Moreover, we hypothesized that additional attributes that i) make the actor more dangerous, or ii) make the observer more vulnerable increase the error asymmetry with regard to inferring anger-proneness, and should therefore correspondingly increase this overestimation bias. In Study 1 (N = 161), a fictitious individual portrayed in a vignette was judged to have higher trait anger than trait disgust, and trait anger ratings were more responsive than trait disgust ratings to behavioral cues of emotionality. In Study 2 (N = 335), participants viewed images of angry or fearful faces. The interaction of factors indicating target's formidability (male sex), target's intent to harm (direct gaze), and perceiver's vulnerability (female sex or high belief in a dangerous world) increased ratings of the target's trait anger but not trait fear.  相似文献   

15.
Maintaining a constant body temperature is critical to the proper functioning of metabolic reactions. Behavioural thermoregulation strategies may minimize the cost of energetic balance when an animal is outside its thermoneutral zone. We investigated whether ambient temperature and relative air humidity influence the use of behavioural strategies by a group of Prince Bernhard's titi monkeys (Callicebus bernhardi) living in a forest fragment. We monitored a social group composed of four individuals (an adult couple and two juveniles) for 1010 h from March to September 2015. We used the instantaneous scan sampling method to record the body posture, the microhabitat, and the occurrence of huddling with group mate(s) when animals were resting. We recorded ambient temperature and relative humidity in the shade every 10 min with a data logger hanging at a height of approximately 5 m. Daytime temperature ranged from 18.5 °C to 38.5 °C and relative humidity ranged from 21% to 97%. Titi monkeys avoided sunny places at higher temperatures, especially above 31 °C. Minimum night temperature did not influence the choice of resting microhabitats during the first hour after sunrise. Sitting was the major resting posture during the day (62%). Titi monkeys increased the use of heat-dissipating postures at ambient temperatures >27 °C. In addition, an increase in relative humidity increased the use of these postures at 26 °C, 27 °C, 29 °C and 33 °C, but caused a decrease at 24 °C. On the other hand, the ambient temperature did not influence the occurrence of huddling. We conclude that microhabitat choice and postural behaviour are important for titi monkeys to prevent overheating and suggest that these behavioural adjustments might also be critical for other tropical arboreal mammals.  相似文献   

16.
《Ecological Engineering》2007,29(3):249-258
Over the course of a year, we conducted a study on future restoration work in the Sanyang wetland, a degraded permanent river wetland that is close to the center of Wenzhou city, China. Our main objective was to plan the restoration by using both structural indices and a valuation of the wetland's ecosystem services, thereby linking the science to human welfare. Based on field surveys and research into the history of the study area, we calculated both the potential and current values of the main ecosystem services. The results showed that the potential value at the Sanyang wetland was 55,332 yuan ha−1 yr−1, while the current value was only 5807 yuan ha−1 yr−1. In other words, 89.5% of the service value needs to be restored for the wetland to reach its potential value. We recommend that the service provided by the wetland's ability to purify the environment needs to be the top priority in restoration. In addition, water and sediment quality should also be greatly improved.  相似文献   

17.
This review discusses major findings from the Women's Health Initiative Memory Study (WHIMS). WHIMS reported hormone therapy (HT) – conjugated equine estrogen (CEE) with or without medroxyprogesterone acetate (MPA) – increased the risk for dementia (HR 1.76 [95% CI, 1.19–2.60]; P = 0.005) and global cognitive decline, with a mean decrement relative to placebo of 0.21 points on the Modified Mini Mental State Examination (3MS) (P = 0.006) in women age 65 and older.A subset of WHIMS participants joined the ancillary WHI Study of Cognitive Aging (WHISCA) trials, in which domain-specific cognitive tests and mood were measured annually. Compared with placebo, CEE + MPA had a negative impact on verbal memory over time (P = 0.01); and CEE-Alone was associated with lower spatial rotational ability (P  0.01) at the initial assessment, but the difference diminished over time.The ancillary WHIMS-MRI study measured subclinical cerebrovascular disease to possibly explain the negative cognitive findings reported by WHIMS and the increased clinical stroke in older women reported by the WHI. WHIMS-MRI reported that while CEE + MPA and CEE-Alone were not associated with increased ischemic brain lesion volume relative to placebo; both CEE + MPA and CEE-Alone were associated with lower mean brain volumes in the hippocampus (P = 0.05); frontal lobe (P = 0.004); and total brain (P = 0.07). HT-associated reductions in hippocampal volumes were greatest in women with baseline 3MS scores ≤90.  相似文献   

18.
Avoiding the innervation zone (IZ) is important when collecting surface electromyographic data. The purposes of this study were threefold: (1) to examine the precision of two different techniques for expressing IZ location for the biceps brachii, (2) to compare these locations between men and women, and (3) to determine if IZ movement with changes in elbow joint angle is related to different anthropometric measures. Twenty-four subjects (mean ± SD ages = 21.8 ± 3.5 yr) performed isometric contractions of the right forearm flexors at each of three separate elbow joint angles (90°, 120°, and 150° between the arm and forearm). During each contraction, the location of the IZ for the biceps brachii was visually identified using a linear electrode array. These IZ locations were expressed in both absolute (i.e. as a distance (mm) from the acromion process) and relative (i.e. as a percentage of humerus length) terms. The results suggested that the estimations of IZ location were more precise when expressed in relative versus absolute terms, and were generally different for men and women. The shift in IZ location with changes in elbow joint angle was not, owever, related to height, weight, or humerus length.  相似文献   

19.
Sibling configuration, including birth order, or the number, age, and sex of siblings is associated with parental resource allocation between children and is thus associated with a person's well-being. Little is known about the association between specific types of siblings and adult health outcomes. Here we test several hypotheses about sibling composition (number of older brothers, older sisters, younger sisters, younger brothers) and adult blood pressure in a foraging-farming society of native Amazonians in Bolivia (Tsimane’). We collected data in 2007 from 374 adults (16–60 years of age) from 196 households in 13 villages. Household random-effects multiple regressions were run using systolic (SBP) or diastolic blood pressure (DBP) as outcomes; covariates included the four sibling categories and control variables (e.g., sex, age, education, body mass index [BMI]). Mean SBP and DBP were 114 (SD = 14) and 66 (SD = 11) mmHg. The prevalence of hypertension was 5.08%. Having an additional younger brother bore a small (3.3–5.9%) positive association with both SBP and DBP, with the effect weakening as people aged. Having an additional younger sister was associated with a small (3.8%) increase in SBP among women, with the magnitude shrinking as people aged. In a large family, the number of younger brothers may exert an impact on an individual's blood pressure.  相似文献   

20.
《Process Biochemistry》2014,49(6):955-962
An extracellular protease from a newly isolated seawater haloalkaliphilic bacterium, haloalkaliphilic bacteria Ve2-20-91 [HM047794], was purified and characterized. The enzyme is a monomer with a 37.2 kDa estimated molecular weight. It catalyzed reactions in the pH range 8–11 and performed optimally at pH 10. While maximal activity occurred at 50 °C, the temperature profile shifted from 50 to 80 °C in 1–3 M NaCl. The enzyme's thermal stability was probed using circular dichroism (CD) spectroscopy with NaCl at 50 and 70 °C. The changes in the enzyme's secondary structure were also analyzed using Fourier transform infrared spectroscopy (FTIR). The N-terminal amino acid sequence GKDGPPGLCGFFGCI exhibited low homology with other bacterial proteases, which highlights the enzyme's novelty. The enzyme was labile in anionic surfactant (1% w/v SDS) but showed stability in non-ionic surfactants (Tween 20, Tween 80 and Triton X-100 all 1% v/v), commercial detergents, and oxidizing and reducing agents. The enzyme's excellent stability in commercial detergents highlights its potential as a detergent additive.  相似文献   

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