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1.
Abstract

Maternal dietary habits influence maternal and foetal health, representing a pathway for intervention to maximise pregnancy outcomes. Advice on energy intake is provided on a trimester basis, with no additional calories required in the first trimester and an additional 340?kcal?d?1 and 452?kcal?d?1 needed for the second and third trimesters. Energy intake depends on pre-gravid body mass index (BMI); underweight women are recommended an increase of 150, 200 and 300?kcal?d?1 during the first, second and third trimester, normal weight women an increase of 0, 350 and 500?kcal?d?1 and obese women an increase of 0, 450 and 350?kcal?day?1. The recommendations for carbohydrate and protein intake are 175?g?d?1 and 0.88–1.1?g?kgBM?d?1, with no change to fat intake. The number of pre-gravid obese women is rising; therefore, we need to regulate weight in women of childbearing age and limit gestational weight gain to within the recommended ranges [overweight women 6.8–11.3?kg and obese women 5.0–9.1?kg]. This can be achieved using nutritional interventions, as dietary changes have been shown to help with gestational weight management. As pregnancy has been identified as a risk factor for the development of obesity, normal weight women should gain 11.5–16.0?kg during pregnancy. While some research has shown that dietary interventions help to regulate gestational weight gain and promote postpartum weight loss to some extent, future research is needed to provide safe and effective guidelines to maximise these effects, while benefitting maternal and foetal health.  相似文献   
2.
Spatial ability (SA) is the cognitive capacity to understand and mentally manipulate concepts of objects, remembering relationships among their parts and those of their surroundings. Spatial ability provides a learning advantage in science and may be useful in anatomy and technical skills in health care. This study aimed to assess the relationship between SA and anatomy scores in first- and second-year medical students. The training sessions focused on the analysis of the spatial component of objects' structure and their interaction as applied to medicine; SA was tested using the Visualization of Rotation (ROT) test. The intervention group (n = 29) received training and their pre- and post-training scores for the SA tests were compared to a control group (n = 75). Both groups improved their mean scores in the follow-up SA test (P < 0.010). There was no significant difference in SA scores between the groups for either SA test (P = 0.31, P = 0.90). The SA scores for female students were significantly lower than for male students, both at baseline and follow-up (P < 0.010). Anatomy training and assessment were administered by the anatomy department of the medical school, and examination scores were not significantly different between the two groups post-intervention (P = 0.33). However, participants with scores in the bottom quartile for SA performed worse in the anatomy questions (P < 0.001). Spatial awareness training did not improve SA or anatomy scores; however, SA may identify students who may benefit from additional academic support.  相似文献   
3.
4.
ABSTRACT

Interval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI ?32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI ?2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10–15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations.  相似文献   
5.

Purpose

Having been rated the world's leader in e-Government Readiness in 2002, 2004, and 2005, Taiwan sought to capitalize on its experience in e-Government implementation by launching, in 2007, a new Government-to-Citizen service entitled “e-Housekeeper”. The success of this service has since then become an important focus for practitioners.

Methodology

The reported research utilizes a psychological approach that is different from the classical models that dominate the existing literature, by examining how citizens’ adaptive–innovative cognitive styles and involvement jointly influence their loyalty intentions towards e-Housekeeper. The style/involvement model is tested by means of information from a sample of 206 Taiwan citizens.

Findings

While innovators initiated e-Housekeeper significantly earlier than others, their usage did not last for long. In contrast, more-involved citizens have shown higher loyalty intentions. More specifically, a combination of decision-making style and involvement significantly influences both when citizens try the service and whether they continue to use it: more-involved adaptors reported the strongest loyalty intentions.

Originality/value

Practical implications of the findings for the style/involvement model are suggested in the context of enhancing the strategic performance of e-Government services. The value of the style/involvement model is enhanced as a social scientific approach to the analysis of consumer innovation.  相似文献   
6.
Of all the senses, that of taste is perhaps the hardest to define and quantify and elucidation of the underlying mechanisms is unrespondingly difficult. This article describes a conceptual model — at the molecular level — for the four basic taste modalities, using apparent specific volume as a fundamental parameter. It also considers possible practical applications.  相似文献   
7.
Gordon Reikard   《Research Policy》2005,34(10):1476-1490
In the recent endogenous growth literature, the trend in output is stochastic, while investment in scientific knowledge is treated as analogous to a capital stock. This paper models both research and development (R&D) and disembodied technical advance using neo-classical equations, which specify the equilibrium stocks as a function of prices and output. The elasticity of R&D in the production function, estimated using factor shares, is time-varying and increasing. Returns to scale are increasing in all factors. The most important aspect of the model is that the equilibrium rate of technical advance is not cyclically invariant, but co-moves with output at business cycle frequencies. This allows the production function to behave as a stochastic trend. Growth accounting demonstrates that long-term variations in the rate of productivity growth have been associated mainly with low-frequency fluctuations in the rate of disembodied technical advance, with secondary effects from the stocks of R&D and physical capital. During the high productivity period 1948–1972, technical advance contributed 1.48 percentage points per year to output, with 0.98 accounted for by R&D. The productivity slowdown of the mid-1970s was accounted by a gradual decline in the effect of R&D, and a more abrupt collapse in disembodied technology. The subsequent productivity revival was associated with two accelerations in disembodied technical advance, the first beginning in the early 1980s, and the second in the mid-1990s. The production function is simulated in a small econometric model. Model simulations find that exogenous shocks to the inflation rate generate significant variations in growth by inducing fluctuations in disembodied technology.  相似文献   
8.
The propagation of elastic waves in a heterogeneous bar of variable cross-sectional area is investigated via use of the method of characteristics andthe Laplace transform technique. The Young's modulus and density are assumed to be representable as either power law or exponential distributions in the axial coordinate. The transform method is used to establish an infinite number of multi-parameter solutions in closed form for either a stress, velocity or displacement type boundary condition. The numerical characteristic computations show excellent agreement when compared to the transform solutions, and are then used to obtain additional solutions not attainable by the transform method. Detailed results and conclusions for a bar of ogival cross-section are given for a wide range of inhomogeneity.  相似文献   
9.
With societal changes rapidly transforming cultures that had been largely homogenous, today’s multi-cultural – and in particular interfaith – families need new educational strategies to help them understand their cultural roots and identify and clarify what aspects of their heritages they wish to nurture and transmit to their children. This paper focuses on a new model for religious education, namely non-doctrinaire “dual-faith” education, which the principal author has helped to develop in the United States (US) through the Interfaith Community (IFC), a small, independent non-profit organisation created and led by dual-faith Jewish/Christian families. The model is premised on the notion that families can have two different faiths in one household and that – with respect and education – families can be harmonious, religion can be transmitted, and tolerance broadly nurtured. While the model is particular to the US and to families with Jewish and Christian heritages, its premises and structure have significant potential to be adaptable to other religious combinations and other cultures and countries. After reviewing relevant literature and situating the IFC model in the global and US contexts, the paper sets out to clarify the importance of the concept, describe its elements, and discuss its implications for religious education in this time of changing ethos and demography.  相似文献   
10.
The authors focused on participation in extracurricular activities as a way of improving the educational outcomes of children with disabilities. Regarding students in the general population, adolescent involvement in extracurricular activities has been shown to have a positive association with school involvement and adolescent self-esteem, academic achievement, and adolescent development. Using the Educational Longitudinal Study dataset, the authors conducted logistic regression analyses to examine the relationship between participation in high school–sponsored extracurricular activities and postsecondary degree completion for students with disabilities. Findings show a statistically significant association between postsecondary degree completion for students with disabilities and extracurricular activity participation, including extent and type of extracurricular activity. Students with disabilities who participate in high school extracurricular activities may have increased likelihood of completing a postsecondary degree. Implications for policy, practice, and future research are discussed.  相似文献   
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