scholarly journals The impact of two-dimensional versus three-dimensional ultrasound exposure on maternal-fetal attachment and maternal health behavior in pregnancy

2006 ◽  
Vol 27 (3) ◽  
pp. 245-251 ◽  
Author(s):  
B. Sedgmen ◽  
C. McMahon ◽  
D. Cairns ◽  
R. J. Benzie ◽  
R. L. Woodfield
Keyword(s):  
Maternal Health ◽  
Health Behavior ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Ultrasound Exposure ◽  
Maternal Fetal Attachment ◽  
Fetal Attachment ◽  
The Impact ◽  
In Pregnancy

scholarly journals Predictors of Sensitivity in Mothers of 8-Month-Old Infants

2013 ◽  
Vol 23 (56) ◽  
pp. 311-320 ◽  
Author(s):  
Patricia Alvarenga ◽  
Maria Virginia Machado Dazzani ◽  
Eulina da Rocha Lordelo ◽  
Cristiane Ajnamei dos Santos Alfaya ◽  
Cesar Augusto Piccinini
Keyword(s):  
Postpartum Depression ◽  
Maternal Mental Health ◽  
Maternal Sensitivity ◽  
Multiple Regression Model ◽  
Third Trimester ◽  
Child Interaction ◽  
Mother Child Interaction ◽  
Maternal Fetal Attachment ◽  
Fetal Attachment ◽  
The Impact

This longitudinal study investigated the impact of maternal mental health, including postpartum depression, and of maternal-fetal attachment, on maternal sensitivity when babies were eight months old. The study included 38 mother-infant dyads. The women answered the SRQ-20 and the Maternal-Fetal Attachment Scale in the third trimester of pregnancy, and the BDI, for evaluation of postpartum depression in the first month following birth. Maternal sensitivity was examined through an observation of mother-child interaction when babies were eight months old. The multiple regression model considering the three factors explained 18.6% of the variance in sensitivity, and only maternal-fetal attachment was a significant predictor. The results indicate the importance of interventions to promote the bond of pregnant women with their babies, which may even minimize possible harmful effects of postpartum depression on mother-child interaction.

scholarly journals An experimental and theoretical investigation of particle–wall impacts in a T-junction

2013 ◽  
Vol 727 ◽  
pp. 236-255 ◽  
Author(s):  
D. Vigolo ◽  
I. M. Griffiths ◽  
S. Radl ◽  
H. A. Stone
Keyword(s):  
Flow Direction ◽  
Three Dimensional ◽  
Stokes Number ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Viscous Boundary Layer ◽  
Particle Tracing ◽  
Two Dimensional Model ◽  
Viscous Boundary ◽  
The Impact

AbstractUnderstanding the behaviour of particles entrained in a fluid flow upon changes in flow direction is crucial in problems where particle inertia is important, such as the erosion process in pipe bends. We present results on the impact of particles in a T-shaped channel in the laminar–turbulent transitional regime. The impacting event for a given system is described in terms of the Reynolds number and the particle Stokes number. Experimental results for the impact are compared with the trajectories predicted by theoretical particle-tracing models for a range of configurations to determine the role of the viscous boundary layer in retarding the particles and reducing the rate of collision with the substrate. In particular, a two-dimensional model based on a stagnation-point flow is used together with three-dimensional numerical simulations. We show how the simple two-dimensional model provides a tractable way of understanding the general collision behaviour, while more advanced three-dimensional simulations can be helpful in understanding the details of the flow.

scholarly journals A monolithic algorithm for the flow simulation of flexible flapping wings

2019 ◽  
Vol 11 ◽  
pp. 175682931984612 ◽  
Author(s):  
Tao Yang ◽  
Mingjun Wei ◽  
Kun Jia ◽  
James Chen
Keyword(s):  
Three Dimensional ◽  
Flow Simulation ◽  
Flapping Wings ◽  
Rigid Sphere ◽  
Two Dimensional ◽  
Unified Framework ◽  
Fluid Structure ◽  
A Cell ◽  
Three Dimensional Configuration ◽  
The Impact

It has been a challenge to simulate flexible flapping wings or other three-dimensional problems involving strong fluid–structure interactions. Solving a unified fluid–solid system in a monolithic manner improves both numerical stability and efficiency. The current algorithm considered a three-dimensional extension of an earlier work which formulated two-dimensional fluid–structure interaction monolithically under a unified framework for both fluids and solids. As the approach is extended from a two-dimensional to a three-dimensional configuration, a cell division technique and the associated projection process become necessary and are illustrated here. Two benchmark cases, a floppy viscoelastic particle in shear flow and a flow passing a rigid sphere, are simulated for validation. Finally, the three-dimensional monolithic algorithm is applied to study a micro-air vehicle with flexible flapping wings in a forward flight at different angles of attack. The simulation shows the impact from the angle of attack on wing deformation, wake vortex structures, and the overall aerodynamic performance.

scholarly journals Discrepancy between two-dimensional and three-dimensional digital subtraction angiography for the planning of endovascular coiling of small cerebral aneurysms <5 mm

2020 ◽  
Vol 26 (6) ◽  
pp. 733-740
Author(s):  
Te-Chang Wu ◽  
Yu-Kun Tsui ◽  
Tai-Yuan Chen ◽  
Ching-Chung Ko ◽  
Chien-Jen Lin ◽  
...  
Keyword(s):  
Digital Subtraction Angiography ◽  
Three Dimensional ◽  
Cerebral Aneurysms ◽  
Endovascular Coiling ◽  
Parent Artery ◽  
Two Dimensional ◽  
Digital Subtraction ◽  
Rotational Angiography ◽  
Treatment Choices ◽  
The Impact

Background To investigate the discrepancy between two-dimensional digital subtraction angiography and three-dimensional rotational angiography for small (<5 mm) cerebral aneurysms and the impact on decision making among neuro-interventional experts as evaluated by online questionnaire. Materials and methods Eight small (<5 mm) ruptured aneurysms were visually identified in 16 image sets in either two-dimensional or three-dimensional format for placement in a questionnaire for 11 invited neuro-interventionalists. For each set, two questions were posed: Question 1: “Which of the following is the preferred treatment choice: simple coiling, balloon remodeling or stent assisted coiling?”; Question 2: “Is it achievable to secure the aneurysm with pure simple coiling?” The discrepancies of angio-architecture parameters and treatment choices between two-dimensional-digital subtraction angiography and three-dimensional rotational angiography were evaluated. Results In all eight cases, the neck images via three-dimensional rotational angiography were larger than two-dimensional-digital subtraction angiography with a mean difference of 0.95 mm. All eight cases analyzed with three-dimensional rotational angiography, but only one case with two-dimensional-digital subtraction angiography were classified as wide-neck aneurysms with dome-to-neck ratio < 1.5. The treatment choices based on the two-dimensional or three-dimensional information were different in 56 of 88 (63.6%) paired answers. Simple coiling was the preferred choice in 66 (75%) and 26 (29.6%) answers based on two-dimensional and three-dimensional information, respectively. Three types of angio-architecture with a narrow gap between the aneurysm sidewall and parent artery were proposed as an explanation for neck overestimation with three-dimensional rotational angiography. Conclusions Aneurysm neck overestimation with three-dimensional rotational angiography predisposed neuro-interventionalists to more complex treatment techniques. Additional two-dimensional information is crucial for endovascular treatment planning for small cerebral aneurysms.

Impact of Cavity on Sunroof Buffeting: A Two Dimensional CFD Study

2004 ◽  
Author(s):  
Chang-Fa An ◽  
Seyed Mehdi Alaie ◽  
Michael S. Scislowicz
Keyword(s):  
Fluid Dynamics ◽  
Wind Tunnel ◽  
Three Dimensional ◽  
Leading Edge ◽  
Two Dimensional ◽  
Deep Insight ◽  
Simulation Results ◽  
Dimensional Simulation ◽  
The Impact ◽  
Insight Into

Driven by fluid dynamics principles, the concept for buffeting reduction, a cavity installed at the leading edge of the sunroof opening, is analyzed. The cavity provides a room to hold the vortex, shed from upstream, and prevents the vortex from escaping and from directly intruding into the cabin. The concept has been verified by means of a two dimensional simulation for a production SUV using the CFD software — FLUENT. The simulation results show that the impact of the cavity is crucial to reduce buffeting. It is shown that the buffeting level may be reduced by 3 dB by adding a cavity to the sunroof configuration. Therefore, the cavity could be considered as a means of buffeting reduction, in addition to the three currently-known concepts: wind deflector, sunroof glass comfort position and cabin venting. Thorough understanding of the buffeting mechanism helps explain why and how the cavity works to reduce buffeting. Investigation of the buffeting-related physics provides a deep insight into the flow nature and, therefore, a useful hint to geometry modification for buffeting reduction. The buffeting level may be further reduced by about 4 dB or more by cutting the corners of the sunroof opening into smooth ramps, guided by ideas coming from careful examining the physics of flow. More work including three dimensional simulation and wind tunnel experiment should follow in order to develop more confidence in the functionality of the cavity to hopefully promote this idea to the level that it can be utilized in a feasible way to address sunroof buffeting.

scholarly journals Evaluation of the impact of the voucher program for improving maternal health behavior and status in Bangladesh

2014 ◽  
Author(s):  
Md. Talukder ◽  
Ubaidur Rob ◽  
Syed Abu Musa ◽  
Ashish Bajracharya ◽  
Kaji Keya ◽  
...  
Keyword(s):  
Maternal Health ◽  
Health Behavior ◽  
Voucher Program ◽  
The Impact

scholarly journals The association of maternal-fetal attachment with smoking and smoking cessation during pregnancy in The FinnBrain Birth Cohort Study

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Heidi Jussila ◽  
Juho Pelto ◽  
Riikka Korja ◽  
Eeva Ekholm ◽  
Marjukka Pajulo ◽  
...  
Keyword(s):  
Smoking Cessation ◽  
Cohort Study ◽  
Early Pregnancy ◽  
Smoking Behavior ◽  
Birth Cohort Study ◽  
Prenatal Smoking ◽  
Smoking In Pregnancy ◽  
Maternal Fetal Attachment ◽  
Fetal Attachment ◽  
In Pregnancy

Abstract Background Smoking in pregnancy constitutes a preventable risk factor for fetal/child development and maternal-fetal attachment (MFA) seems to contain a momentum that can break the chain of adverse outcomes by promoting maternal prenatal health practices. This study aimed to explore the association of MFA with smoking at any time during pregnancy and smoking cessation in early pregnancy, and the modifying role of MFA on the expected effects of education and prenatal psychological distress (PPD) on prenatal smoking behavior. Methods The pregnant women (n = 3766) participated in the The FinnBrain Birth Cohort Study in Finland between December 2011 and April 2015. The binary outcomes, smoking at any time during pregnancy and smoking cessation in early pregnancy, were obtained from self-reports at gestational weeks (gwks) 14 and 34 and The Finnish Medical Birth Register. MFA was assessed with the Maternal-Fetal Attachment Scale (MFAS) at gwks 24 and 34. Logistic regression analyses were used to determine the association between MFA and maternal prenatal smoking behavior. Findings The prevalence of smoking was 16.5%, and 58.1% of the smokers quit smoking during pregnancy. The independent associations of total MFA scores with prenatal smoking behavior were not established (aOR = 1.00-1.02, multiplicity adjusted p > 0.05). A higher score in the altruistic subscale of MFA, Giving of self, associated with a higher probability of smoking cessation (24 gwks: aOR = 1.13, 95% CI [1.04, 1.24], p = 0.007, multiplicity adjusted p = 0.062; 34 gwks: aOR = 1.17, 95% CI [1.07, 1.29], p < 0.001, multiplicity adjusted p = 0.008). The modifying effect of MFA on the observed associations between PPD and smoking in pregnancy and between maternal education and smoking in pregnancy / smoking cessation in early pregnancy was not demonstrated. Conclusions The altruistic dimension of maternal-fetal attachment associates with an increased probability of smoking cessation during pregnancy and therefore strengthening altruistic maternal-fetal attachment may constitute a promising novel approach for interventions aiming at promoting smoking cessation during pregnancy.

scholarly journals Assessing the Impact of the Tropopause on Mountain Waves and Orographic Precipitation Using Linear Theory and Numerical Simulations

2015 ◽  
Vol 72 (2) ◽  
pp. 803-820 ◽  
Author(s):  
Nicholas Siler ◽  
Dale Durran
Keyword(s):  
Numerical Simulations ◽  
Linear Theory ◽  
Three Dimensional ◽  
Orographic Precipitation ◽  
Two Dimensional ◽  
Tropopause Height ◽  
Atmospheric Conditions ◽  
Mountain Waves ◽  
Wave Induced ◽  
The Impact

Abstract The partial reflection of mountain waves at the tropopause has been studied extensively for its contribution to downslope windstorms, but its impact on orographic precipitation has not been addressed. Here linear theory and numerical simulations are used to investigate how the tropopause affects the vertical structure of mountain waves and, in turn, orographic precipitation. Relative to the no-tropopause case, wave-induced ascent above the windward slope of a two-dimensional ridge is found to be enhanced or diminished depending on the ratio of the tropopause height to the vertical wavelength of the mountain waves—defined here as the “nondimensional tropopause height” . In idealized simulations of flow over both two-dimensional and three-dimensional ridges, variations in are found to modulate the precipitation rate by roughly a factor of 2 under typical atmospheric conditions. The sensitivity of precipitation to is related primarily to the depth of windward ascent but also to the location and strength of leeside descent, with significant impacts on the distribution of precipitation across the range (i.e., the rain-shadow effect). Using a modified version of Smith and Barstad’s orographic precipitation model, variations in are found to produce significant rain-shadow variability in the Washington Cascades, perhaps explaining some of the variability in rain-shadow strength observed among Cascade storms.

Two-dimensional (2D) fabrics and three-dimensional (3D) preforms for ballistic and stabbing protection: A review

2016 ◽  
Vol 87 (18) ◽  
pp. 2275-2304 ◽  
Author(s):  
Kadir Bilisik
Keyword(s):  
Impact Resistance ◽  
Three Dimensional ◽  
Shear Thickening ◽  
High Strength ◽  
Computational Techniques ◽  
Two Dimensional ◽  
Shear Thickening Fluids ◽  
Recent Developments ◽  
Ballistic Properties ◽  
The Impact

In this study, the impact resistance of two-dimensional (2D) fabrics and three-dimensional (3D) preforms is explained. These fabrics and preforms include 2D and 3D woven and knitted flat and circular fabrics. Various types of soft/layered structures as well as rigid composite are outlined with some design examples for ballistic and stab threats. The recent developments in nanotubes/nanofibers and shear-thickening fluids (STF) for ballistic fabrics are reviewed. The ballistic properties of single- and multi-layered fabrics are discussed. Their impact mechanism is explained for both soft vest and rigid armor applications. Analytical modeling and computational techniques for the estimation of ballistic properties are outlined. It is concluded that the ballistic/stab properties of fiber-reinforced soft and rigid composites can be enhanced by using high-strength fibers and tough matrices as well as specialized nanomaterials. Ballistic/stab resistance properties were also improved by the development of special fabric architectures. All these design factors are of primary importance for achieving flexible and lightweight ballistic structures with a high ballistic limit.

scholarly journals Double-Diffusive Convection in a Stochastic Shear

2015 ◽  
Vol 45 (12) ◽  
pp. 3155-3167 ◽  
Author(s):  
Timour Radko ◽  
James Ball ◽  
John Colosi ◽  
Jason Flanagan
Keyword(s):  
Internal Waves ◽  
Phase Distribution ◽  
Three Dimensional ◽  
Vertical Shear ◽  
Two Dimensional ◽  
Salt Fingers ◽  
Diffusive Dynamics ◽  
Wave Induced ◽  
The Impact ◽  
Double Diffusive

AbstractAn attempt is made to quantify the impact of stochastic wave–induced shears on salt fingers associated with internal waves in the ocean. The wave environment is represented by the superposition of Fourier components conforming to the Garrett–Munk (GM) spectrum with random initial phase distribution. The resulting time series of vertical shear are incorporated into a finger-resolving numerical model, and the latter is used to evaluate the equilibrium diapycnal fluxes of heat and salt. The proposed procedure makes it possible to simulate salt fingers in shears that are representative of typical oceanic conditions. This study finds that the shear-induced modification of salt fingers is largely caused by near-inertial motions. These relatively slow waves act to align salt fingers in the direction of shear, thereby rendering the double-diffusive dynamics effectively two-dimensional. Internal waves reduce the equilibrium vertical fluxes of heat and salt by a factor of 2 relative to those in the unsheared three-dimensional environment, bringing them close to the values suggested by corresponding two-dimensional simulations.

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