296 research outputs found

    Factors affecting paternal adjustment during the transition to parenthood

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    An emerging body of research is identifying factors which put individuals at risk for experiencing a difficult adjustment during the transition to parenthood. The purpose of this study was to test a model for the prediction and identification of paternal risk factors. Forty seven couples expecting their first child were the subjects. Questionnaires which assessed paternal expectations regarding parenthood and prenatal marital satisfaction were administered in the third trimester of their wife\u27s pregnancy. Two months postpartum, a second questionnaire was administered which included measures of paternal violated expectations, paternal postpartum marital satisfaction, paternal stress, infant temperament, maternal marital satisfaction, maternal postpartum depression, the presence of external support and maternal change in employment status. Multiple regression analyses were conducted to identify which variables significantly predicted the presence of postpartum paternal stress. In general, two hypotheses were supported. Paternal postpartum stress was predicted by (1) higher quality of paternal marital satisfaction assessed prenatally, and (2) infants\u27 whose temperaments were paternally assessed as slowly adaptable, less persistent, and more distractable. Statistically significant bivariate correlations were also identified among the predictor variables. Paternal prenatal marital satisfaction was positively correlated with maternal and paternal postpartum marital satisfaction, and a higher incidence of paternal violated expectations. A higher quality of maternal marital satisfaction was correlated with a lower incidence of maternal postpartum depression. Various infant temperament subscales were correlated with other temperament subscales and with some of the predictor variables. The clinical and research implications associated the findings of this study were discussed

    Stability and Instability of Relativistic Electrons in Classical Electro magnetic Fields

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    The stability of matter composed of electrons and static nuclei is investigated for a relativistic dynamics for the electrons given by a suitably projected Dirac operator and with Coulomb interactions. In addition there is an arbitrary classical magnetic field of finite energy. Despite the previously known facts that ordinary nonrelativistic matter with magnetic fields, or relativistic matter without magnetic fields is already unstable when the fine structure constant, is too large it is noteworthy that the combination of the two is still stable provided the projection onto the positive energy states of the Dirac operator, which defines the electron, is chosen properly. A good choice is to include the magnetic field in the definition. A bad choice, which always leads to instability, is the usual one in which the positive energy states are defined by the free Dirac operator. Both assertions are proved here.Comment: LaTeX fil

    Assessment and Suggestions to Improve the Commercial Building Module of EIA-NEMS

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    Over the last 7 years, the Energy Systems Laboratory (ESL) of Texas A&M University built up an extensive database of monitored hourly energy use data in about 150 institutional, hospital and state and governmental buildings as a part of the LoanSTAR energy monitoring program. Further, the ESL has acquired expertise in commercial buildings simulations as well as in related technology improvements. This study included two tasks. First, the NEMS CSD-EUI matrix data for the Texas region was compared to those determined from end-use monitored data from the Texas LoanSTAR database. Second, the interaction effects between lighting and heating and cooling energy use for seven different building categories in three different geographic locations were characterized using the ASEAM building simulation software.The National Energy Modeling System (NEMS) is a comprehensive, computer-based, energy-economy modeling system developed and maintained by the Department of Energy's Energy Information Administration (EIA). NEMS forecasts the national production, imports, conversion, consumption, and prices of energy out to 2015, subject to macroeconomic assumptions, world energy markets, resource availability and costs, technological developments, and behavioral and technological choice criteria. NEMS has nine program modules of which the Commercial Sector Demand (CSD) module is one. Currently the CSD module uses a matrix of Energy Use Intensities (EUls) gleaned from the 1989 CBECS database to model service demand per major fuel type for eight different geographic census divisions and eleven different building types

    The exact Darwin Lagrangian

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    Darwin (1920) noted that when radiation can be neglected it should be possible to eliminate the radiation degrees-of-freedom from the action of classical electrodynamics and keep the discrete particle degrees-of-freedom only. Darwin derived his well known Lagrangian by series expansion in v/cv/c keeping terms up to order (v/c)2(v/c)^2. Since radiation is due to acceleration the assumption of low speed should not be necessary. A Lagrangian is suggested that neglects radiation without assuming low speed. It cures deficiencies of the Darwin Lagrangian in the ultra-relativistic regime.Comment: 2.5 pages, no figure

    Ionization Potential of the Helium Atom

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    Ground state ionization potential of the He^4 atom is evaluated to be 5 945 204 221 (42) MHz. Along with lower order contributions, this result includes all effects of the relative orders alpha^4, alpha^3*m_e/m_alpha and alpha^5*ln^2(alpha).Comment: 4 page

    Effects of diets high in animal or plant protein on oxidative stress in individuals with type 2 diabetes: a randomized clinical trial

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    High-protein diet is a promising strategy for diabetes treatment supporting body weight control, improving glycaemic status, cardiovascular risk factors and reducing liver fat. Here, we investigated effects of diets high in animal (AP) or plant (PP) protein on oxidative stress and antioxidant status in individuals with type 2 diabetes (T2DM). 37 obese individuals (age 64.3 ± 1.0 years) with T2DM were randomized to an isocaloric diet (30 energy(E)% protein, 30E% fat and 40E% carbohydrates) rich in AP or PP for 6 weeks. Markers of oxidative and nitrosative stress and antioxidant status in plasma and nitrate/nitrite levels in urine were assessed. Gene expression in subcutaneous adipose tissue (SAT) was analyzed by RNA-Seq and real-time PCR.Both AP and PP diets similarly reduced plasma levels of malondialdehyde (P(AP) = 0.003, P(PP) = 1.6x10(-4)) and protein carbonyls (P(AP) = 1.2x10(-4), P(PP) = 3.0x10(-5)) over 6 weeks. Nitrotyrosine (NT) increased upon both AP and PP diets (PAP = 0.005,PPP = 0.004). SAT expression of genes involved in nitric oxide (NO) and oxidative stress metabolism and urine NO metabolite (nitrate/nitrite) levels were not changed upon both diets. Plasma levels of carotenoids increased upon PP diet, whereas retinol, alpha- and gamma-tocopherol slightly decreased upon both diets. AP and PP diets similarly improve oxidative stress but increase nitrosative stress markers in individuals with T2DM. Mechanisms of the NT regulation upon high-protein diets need further investigation

    Constraints on Light Pseudoscalars Implied by Tests of the Gravitational Inverse-Square Law

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    The exchange of light pseudoscalars between fermions leads to a spin-independent potential in order g^4, where g is the Yukawa pseudoscalar-fermion coupling constant. This potential gives rise to detectable violations of both the weak equivalence principle (WEP) and the gravitational inverse-square law (ISL), even if g is quite small. We show that when previously derived WEP constraints are combined with those arisingfrom ISL tests, a direct experimental limit on the Yukawa coupling of light pseudoscalars to neutrons can be inferred for the first time (g_n^2/4pi < 1.6 \times 10^-7), along with a new (and significantly improved) limit on the coupling of light pseudoscalars to protons.Comment: 12 pages, Revtex, with 1 Postscript figure (submitted to Physical Review Letters

    Coordinate-space approach to the bound-electron self-energy: Self-Energy screening calculation

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    The self-energy screening correction is evaluated in a model in which the effect of the screening electron is represented as a first-order perturbation of the self energy by an effective potential. The effective potential is the Coulomb potential of the spherically averaged charge density of the screening electron. We evaluate the energy shift due to a 1s1/21s_{1/2}, 2s1/22s_{1/2}, 2p1/22p_{1/2}, or 2p3/22p_{3/2} electron screening a 1s1/21s_{1/2}, 2s1/22s_{1/2}, 2p1/22p_{1/2}, or 2p3/22p_{3/2} electron, for nuclear charge Z in the range 5≀Z≀925 \le Z\le 92. A detailed comparison with other calculations is made.Comment: 54 pages, 10 figures, 4 table

    Relativistic and QED corrections to the 2pσu(υ=1)2p\sigma_{u}(\upsilon = 1) vibrational state of the H2+H^{+}_{2} molecular ion

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    Relativistic and QED corrections to the recently discovered first vibrational 2pσu2p\sigma_u state are presented. This state has an extremely small nonrelativistic binding energy EB=1.085045252(1)×10−9E_B=1.085045252(1)\times10^{-9} a.u. Its wave functions has a maximum at R≈100R\approx100 a.u. and extends up to several hundreds. It is shown that this state does not disappear if higher order relativistic and QED corrections, including the Casimir--Polder effect, are taken into account

    Quantum Electrodynamics of the Helium Atom

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    Using singlet S states of the helium atom as an example, I describe precise calculation of energy levels in few-electron atoms. In particular, a complete set of effective operators is derived which generates O(m*alpha^6) relativistic and radiative corrections to the Schr"odinger energy. Average values of these operators can be calculated using a variational Schr"odinger wave function.Comment: 23 pages, revte
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