Marriage and housework

2020 ◽  
Author(s):  
By Cristina Borra ◽  
Martin Browning ◽  
Almudena Sevilla
Keyword(s):  
Time Varying ◽  
Cross Sectional ◽  
Housework Time ◽  
Married Individuals ◽  
The Cross ◽  
The Difference ◽  
Time Invariant

Abstract This article provides insights into the gains of forming a couple by estimating how much of the difference in housework between single and married individuals is causal and how much is due to selection. Time-varying observed variables and time-invariant heterogeneity explains about half of the observed differences in housework documented in the cross-sectional data. There remains a genuine one-and-a-half-hour increase per week in housework time for each partner, with women specializing in routine and men in non-routine housework tasks.

Computational Investigation on the Dispersive Transport of Angiographic Contrast Injected Antegradely Into Flow in a Tube

2007 ◽  
Author(s):  
Qing Hao ◽  
Baruch B. Lieber
Keyword(s):  
Coordinate System ◽  
Cross Section ◽  
Single Molecule ◽  
Molecular Diffusion ◽  
Local Concentration ◽  
Dispersive Transport ◽  
Cross Sectional ◽  
Advection Dispersion ◽  
The Cross ◽  
The Difference

When a solute such as angiographic contrast is introduced into a solvent such as blood analog fluid flowing in a straight circular tube, it spreads under the combined action of molecule diffusion and the variation of velocity over the cross-section [8]. If two molecules are being carried in the flow, for example, one in the center and one near the wall, the rate of separation caused by the difference in bulk velocity will greatly exceed that caused by molecule motion. Given enough time, any single molecule would wander randomly throughout the cross section of the pipe because of molecular diffusion, and would sample at random all the advective velocities [4]. Therefore, Taylor [8] adopted the Lagrangian approach to the problem, casting the equations in a coordinate system that moves with the average velocity of the flow and replacing the molecular diffusion coefficient with a dispersion coefficient, and the local concentration with the cross sectional mean concentration. Recasting Taylor’s equation in an inertial coordinate system one obtained the so called advection-dispersion equation.

scholarly journals Occupational lifting and risk of hypertension, stratified by use of anti-hypertensives and age - a cross-sectional and prospective cohort study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Mette Korshøj ◽  
Harald Hannerz ◽  
Ruth Frikke-Schmidt ◽  
Jacob L. Marott ◽  
Peter Schnohr ◽  
...  
Keyword(s):  
Prospective Analysis ◽  
Linear Regression Models ◽  
Cross Sectional ◽  
General Population Study ◽  
The Cross ◽  
The Difference ◽  
Cross Sectional Design ◽  
Study Designs ◽  
Sectional Analysis

Abstract Background Heavy occupational lifting is prevalent in the general working population and is sparsely reported to associate with hypertension, especially among older and hypertensive workers. We investigated if heavy occupational lifting is associated with hypertension and blood pressure (BP) in both cross-sectional and prospective study designs in the Copenhagen General Population Study, stratified by age, and use of anti-hypertensives. Methods Participation was conducted following the declaration of Helsinki and approved by the ethical committee (H-KF-01-144/01). By multivariable logistic and linear regression models, we investigated the association between heavy occupational lifting and hypertension, in a cross-sectional design (n = 67,363), using anti-hypertensives or BP ≥140/≥90 mmHg as outcome, and in a prospective design (n = 7020) with an above-median change in systolic BP (SBP) from baseline to follow-up and/or a shift from no use to use of anti-hypertensives as outcome, with and without stratification by age and use of anti-hypertensives. Results The odds ratio for hypertension was estimated at 0.97 (99% CI: 0.93–1.00) in the cross-sectional analysis, and at 1.08 (99% CI: 0.98–1.19) in the prospective analysis. The difference in SBP among workers with versus without heavy occupational lifting was estimated at − 0.29 mmHg (99% CI -0.82 – 0.25) in the cross-sectional and at 1.02 mmHg (99% CI -0.41 – 2.45) in the prospective analysis. No significant interaction between heavy occupational lifting and age, nor use of anti-hypertensives were shown. Conclusions Only the prospective analysis indicated heavy occupational lifting to increase the risk of hypertension. Further research on the association between occupational lifting and hypertension are needed.

scholarly journals The age U-shape in Europe: the protective role of partnership

2021 ◽  
Author(s):  
Andrew E. Clark ◽  
Angela Greulich ◽  
Hippolyte d’Albis
Keyword(s):  
Life Satisfaction ◽  
Protective Role ◽  
Significant Shift ◽  
Cross Sectional ◽  
Compositional Effects ◽  
The Cross ◽  
The Difference

In this study, we ask whether the U-shaped relationship between life satisfactionand age is flatter for individuals who are partnered. An analysis of cross-sectionalEU-SILC data indicates that the decline in life satisfaction from the teens to thefifties is almost four times larger for non-partnered than for partnered individuals,whose life satisfaction essentially follows a slight downward trajectory with age.However, the same analysis applied to three panel datasets (BHPS, SOEP andHILDA) reveals a U-shape for both groups, albeit somewhat flatter for the partneredthan for the non-partnered individuals. We suggest that the difference between thecross-sectional and the panel results reflects compositional effects: i.e., there isa significant shift of the relatively dissatisfied out of marriage in mid-life. Thesecompositional effects tend to flatten the U-shape in age for the partnered individualsin the cross-sectional data.

scholarly journals A Superellipse with Deformation and Its Application in Describing the Cross-Sectional Shapes of a Square Bamboo

Symmetry ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2073
Author(s):  
Weiwei Huang ◽  
Yueyi Li ◽  
Karl J. Niklas ◽  
Johan Gielis ◽  
Yongyan Ding ◽  
...  
Keyword(s):  
Cross Sections ◽  
Large Scale ◽  
Deformation Parameter ◽  
Rotational Symmetry ◽  
Cross Sectional ◽  
Future Studies ◽  
Initial Application ◽  
Stem Development ◽  
The Cross ◽  
The Difference

Many cross-sectional shapes of plants have been found to approximate a superellipse rather than an ellipse. Square bamboos, belonging to the genus Chimonobambusa (Poaceae), are a group of plants with round-edged square-like culm cross sections. The initial application of superellipses to model these culm cross sections has focused on Chimonobambusa quadrangularis (Franceschi) Makino. However, there is a need for large scale empirical data to confirm this hypothesis. In this study, approximately 750 cross sections from 30 culms of C. utilis were scanned to obtain cross-sectional boundary coordinates. A superellipse exhibits a centrosymmetry, but in nature the cross sections of culms usually deviate from a standard circle, ellipse, or superellipse because of the influences of the environment and terrain, resulting in different bending and torsion forces during growth. Thus, more natural cross-sectional shapes appear to have the form of a deformed superellipse. The superellipse equation with a deformation parameter (SEDP) was used to fit boundary data. We find that the cross-sectional shapes (including outer and inner rings) of C. utilis can be well described by SEDP. The adjusted root-mean-square error of SEDP is smaller than that of the superellipse equation without a deformation parameter. A major finding is that the cross-sectional shapes can be divided into two types of superellipse curves: hyperellipses and hypoellipses, even for cross sections from the same culm. There are two proportional relationships between ring area and the product of ring length and width for both the outer and inner rings. The proportionality coefficients are significantly different, as a consequence of the two different superellipse types (i.e., hyperellipses and hypoellipses). The difference in the proportionality coefficients between hyperellipses and hypoellipses for outer rings is greater than that for inner rings. This work informs our understanding and quantifying of the longitudinal deformation of plant stems for future studies to assess the influences of the environment on stem development. This work is also informative for understanding the deviation of natural shapes from a strict rotational symmetry.

scholarly journals EXPERIMENTAL STUDIES OF A TWO-GRADE CHOPPER OF BEETS

2019 ◽  
Vol 14 (2) ◽  
pp. 100-105
Author(s):  
Динар Исмагилов ◽  
Dinar Ismagilov ◽  
Марат Калимуллин ◽  
Marat Kalimullin ◽  
Ринат Абдрахманов ◽  
...  
Keyword(s):  
Rotational Speed ◽  
Experimental Studies ◽  
Cross Sectional ◽  
Flexible Working ◽  
Hydraulic Motors ◽  
Working Element ◽  
The Cross ◽  
The Difference ◽  
The Republic ◽  
Cutting Height

The two-grade rotary chopper BIR-2 of root and tuber crops with flexible working elements is designed to remove the beets of vegetable leaves before or during the harvest of carrots. It is proposed to use it together with an undermining machine in an aggregate with a tractor of the 1.4 kN class of thrust with a front and rear hitch. In this case, the chopper of beets is hung on the front hitch of the power means, and the working units are driven in rotation by hydraulic motors, which allows the two unitized devices to operate independently of each other. Laboratory studies of the effect of rotational speed, type and diameter of the cross section of work items on the amplitude of their oscillations were carried out on the soil plots Kazan State Agrarian University. Several types of work items were used in the experiments: a rubberized metal cable, a rubber-fabric element, a fishing line. The approbation was carried out when removing the tops of carrots. At this stage of experimental studies, the rotational speed of the working unit was 700 min-1, and the onward speed was 2.5 m/sec. Later, for the experiments, the plasticine pins were made, using which, with the necessary accuracy, the lower and upper points of contact of the working element can be determined, which, in turn, makes it possible to calculate the amplitude of transverse oscillations as the difference between these points. The rotational speed of the working elements at this stage varied from 500 to 900 min-1, the cross-sectional diameter - from 5 to 7 mm. According to the test results, the most rational diameter of the working element, which is equal to 5.5 mm, was determined, the required cutting height of the carrot tops in accordance with agrotechnical requirements, which is 0 ... 20 mm at a frequency of rotation of the working elements 800 min-1. According to the testing results of the developed unit under production conditions, which were carried out in JSC “Kyrlay” of the Republic of Tatarstan, the rational speed of the unit movement was chosen, which amounted to 3.3 m/sec.

scholarly journals Effect of physical exercises and perceived stress interaction on students’ satisfaction with life

2019 ◽  
Vol 23 (1) ◽  
pp. 30-35
Author(s):  
V.O. Olefir ◽  
M.A. Kuznetsov ◽  
V.V. Plokhikh
Keyword(s):  
Physical Activity ◽  
University Students ◽  
Perceived Stress ◽  
Satisfaction With Life ◽  
Cross Sectional ◽  
Moderator Analysis ◽  
Physical Exercises ◽  
The Cross ◽  
The Difference ◽  
Students Satisfaction

Purpose : to find out the effect of regular physical exercises and perceived stress interaction on students’ satisfaction with life. Material and methods : The study involved university students (n = 355; М age = 19,97; SD = 2,12). The moderator analysis was conducted according to the cross-sectional questionnaire. Results : It is determined that the difference in students' satisfaction with life at the average and high perceived stress is due to physical exercises. The influence of the interaction of variables (physical activity x perceived stress) on satisfaction with life was statistically significant. Conclusions : It is revealed the peculiarities of interaction between the physical exercises and perceived stress. The reduce of satisfaction with life under the influence of perceived stress is more typical for those students who do not regularly practice physical exercises. Physical exercises act as a buffer against stress.

Time-varying betas and the cross-sectional return–risk relation: evidence from the UK

2004 ◽  
Vol 10 (4) ◽  
pp. 255-276 ◽  
Author(s):  
Patricia Fraser ◽  
Foort Hamelink * ◽  
Martin Hoesli ◽  
Bryan Macgregor
Keyword(s):  
Time Varying ◽  
Cross Sectional ◽  
The Cross ◽  
The Uk

Testing the Cross-Sectional Microhardness in Sheets with A 0.08% Carbon Concentration

2021 ◽  
Vol 316 ◽  
pp. 269-275
Author(s):  
Sergey A. Tipalin ◽  
Vladislav B. Belousov ◽  
Svetlana I. Lyubetskaya
Keyword(s):  
Carbon Concentration ◽  
Research Team ◽  
Sheet Steel ◽  
Rolled Sheet ◽  
Hardness Distribution ◽  
Cross Sectional ◽  
Accumulated Strain ◽  
Cold Rolled ◽  
The Cross ◽  
The Difference

The research team studied the hardness of cold-rolled sheets of varying thicknesses containing 0.08% carbon. Greater thickness correlated with lower mean hardness. The hardness was found to drop in the middle of a plate and to increase gradually towards the edges. This pattern was observed regardless of the thickness of thin cold-rolled sheet steel. The change in hardness may indicate uneven accumulated strain in the sheets rolled to a desired value. Pre-hardened sheets were analyzed to find whether the hardness was homogeneous through the thickness. The material was hardened by axial tensioning. Analysis showed that at greater accumulated strain, the through-thickness hardness was affected as well. However, the difference was less pronounced at the edge as well as in the middle of sheets. The paper shows graphs of the hardness distribution through thickness.

CALCULATION OF NON-STANDARD SINGLE CARGO HOOK

2021 ◽  
pp. 148-155
Author(s):  
В.И. Сероштан ◽  
П.В. Витчук ◽  
В.Ю. Анцев ◽  
Н.А. Витчук
Keyword(s):  
Cross Sections ◽  
Hot Stamping ◽  
Cross Sectional Area ◽  
Design Stage ◽  
Sectional Area ◽  
Current Standard ◽  
Cross Sectional ◽  
The Cross ◽  
The Difference ◽  
Positive Effect

Oднорогие грузовые крюки грузоподъемных кранов изготавливают способом горячей штамповки и свободной ковки. Действующим стандартом предусмотрено 26 типоразмеров заготовок грузовых крюков. Очевидно, что номенклатура стандартных однорогих грузовых крюков ограничена и не может удовлетворить всего многообразия требований при создании специальных грузоподъемных машин для конкретных условий. В случае применения нестандартных крюков или при нестандартной грузоподъемности крана проводится поверочный расчет крюка. В существующем упрощенном методе расчета однорогих грузовых крюков сечения крюка заменяют правильной трапецией без учета скруглений. Поэтому предложен уточненный метод расчета нестандартных однорогих крюков грузоподъемных кранов. Осуществлена проверка предлагаемого метода при помощи SolidWorks, доказана его точность. Проведен сравнительный анализ результатов вычислений по предлагаемому и существующему упрощенному методам. Сравнение расчетных площадей сечений грузовых крюков, полученных предлагаемым и упрощенным методами, показывает, что разница между ними для стандартных крюков колеблется в пределах 6-10%. В среднем площадь сечения крюка, полученная по предлагаемому уточненному расчету, меньше, чем по упрощенному на 8%. Результаты расчета точной площади поперечного сечения грузового крюка и полученные на их основе значения напряжений в опасных сечениях позволяют на стадии проектирования достичь оптимальной формы грузового крюка. Это позволит в процессе производства получить наименьшее значение металлоемкости грузового крюка, что положительно скажется на его себестоимости Load single-hooks for cranes are made by hot stamping and free forging. The current standard provides for 26 standard sizes of cargo hook blanks. Obviously, the range of standard single-horned cargo hooks is limited and cannot satisfy the whole variety of requirements when creating special lifting machines for specific conditions. In the case of using non-standard hooks or with non-standard crane lifting capacity, a verification calculation of the hook is carried out. In the existing simplified method for calculating one-horned load hooks, the cross-sections of the hook are replaced with a regular trapezoid without taking into account the fillets. Therefore, we propose a refined method for calculating non-standard single-horned hooks of hoisting cranes. We tested the method using SolidWorks and proved its accuracy. We carried out a comparative analysis of the results of calculations by the proposed and existing simplified methods. Comparison of the calculated cross-sectional areas of cargo hooks obtained by the proposed and simplified methods shows that the difference between them for standard hooks ranges from 6-10%. On average, the cross-sectional area ofthe hook, obtained according to the proposed refined calculation, is less than the simplified one by 8%. The results of calculating the exact cross-sectional area of the load hook and the values of stresses in dangerous sections obtained on their basis allow one at the design stage to achieve the optimal shape of the load hook. This will allow one in the production process to obtain the smallest value of the metal consumption of the cargo hook, which will have a positive effect on its cost

scholarly journals EFEKTIFITAS TRIPLE C PARENTING TERHADAP PERSEPSI PENGASUH TENTANG OBESITAS DINI ANAK USIA 3-5 TAHUN

2018 ◽  
Vol 11 (2) ◽  
pp. 104-113
Author(s):  
Elly Dwi Masita Masita ◽  
Rizki Amalia
Keyword(s):  
Caloric Intake ◽  
Not Given ◽  
Cross Sectional ◽  
Purposive Sampling ◽  
Significant Difference ◽  
Instrument Analysis ◽  
Prevalence Of Obesity ◽  
Environment Perception ◽  
The Cross ◽  
The Difference

The prevalence of obesity in under-fives in Indonesia in 2013 reaches 19.1% and increases annually. In Surabaya, the prevalence of obesity in infants reaches 10.6%. Early obesity in toddlers due to several factors, among others, nutrition during pregnancy, when first providing MPASI, heredity, health, environment, perception, activity, more caloric intake. The aim of this research is to know the difference in perception between the caregiver who is given triple C parenting treatment and which is not given treatment. The type of this research is the analytical queasy experiment with the cross-sectional approach involving 60 respondents divided 30 as control respondent and 30 as respondent treatment. The sampling used purposive sampling with perception questionnaire instrument. Analysis using Mann Whitney. The results of the test obtained mean = 2.80 median = 3.00 with p = 0.001 (p <0.005). There was a significant difference in perception on caregivers who were given triple c parenting with p = 0.001

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