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Hurricane Katrina exposed serious deficiencies in the social support safety net at the federal, state, and local level. This article explores the impacts of the disrupted safety net through participant observation and interviews with service providers and evacuees resettled in one southern city. Their stories illustrate how vulnerable low-income groups struggle to cope with disaster within the context of inadequate larger support systems and the legacy of racism. The data also illustrate the limits of the local resources and response, given the years of retrenchment and underfunding and increasing dependence on nongovernmental sources of support. The authors explore some of the implications of this trend for evacuees' long-term recovery and social work intervention. [ABSTRACT FROM AUTHOR]

The authors employ data from the Welfare, Children, and Families project, a probability sample of 2,402 low-income women with children living in low-income neighborhoods in Boston, Chicago, and San Antonio, to test whether religious attendance is associated with parental satisfaction, perceived parental demands, and parental distress over 2 years. They also consider three potential mediators of the association between religious attendance and attitudes toward parenting: social support, self-esteem, and psychological distress. Results show that women who frequently attend religious services report greater parental satisfaction, perceive fewer parental demands, and report less parental distress than do women who attend less frequently. The authors also find that the mediators under study help to partially explain the relationship between religious attendance and attitudes toward parenting. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study compares various dimensions of physical and emotional health between older Mexican-origin individuals in the United States and in Mexico. METHOD: The samples are drawn from the Mexican Health and Aging Study (MHAS) and the Hispanic Established Epidemiologic Study of the Elderly (H-EPESE) and include 3,875 Mexican residents with no history of residence in the United States and 2,734 Mexican-origin individuals 65 and older who live in the southwestern United States. RESULTS: Both immigrant and native-born Mexican-origin elders in the United States report more chronic conditions than elderly Mexicans, but they report fewer symptoms of psychological distress. Longer residence in the United States is associated with higher body mass index scores. DISCUSSION: The discussion addresses the possibility that access to care influences reports of diagnosed conditions and touches on issues of comparability in cross-cultural research and the difficulty in clearly distinguishing cultural and system-level factors in the production and measurement of health. [ABSTRACT FROM AUTHOR]

Longitudinal ethnographic data of 49 families in the San Antonio site of the Three City Study illustrate the ways in which families that remain on welfare differ in important ways from families in which the mother is employed. Families that remain on welfare experience substantial health and emotional problems; have limited access to informal supports; and are headed by mothers with little education or prior work experience. These ethnographic findings have important implications for survey-based studies in which the selection problems can easily affect results when families on welfare are compared to wage-reliant families. [ABSTRACT FROM AUTHOR]

OBJECTIVES: This article examines the impact of disability, cognitive status, and social support on nursing home use in a sample of older Mexican Americans. METHOD: We used four waves of the Hispanic Established Populations for Epidemiologic Studies of the Elderly (H-EPESE), a longitudinal study of 3,050 older Mexican Americans living in the Southwest initially contacted in 1993 to 1994. RESULTS: The findings reveal that advanced age, being a man, activities of daily living disability, and cognitive impairment are strong predictors of institutionalization and death. Living with family, arriving in the United States in late life, and access to social support independently decreased the probability of dying in a nursing home. DISCUSSION: Although it is clear that adequate social support can make it possible for an impaired older person to remain in the community serious impairment can eventually overwhelm even a supportive network and result in the institutionalization of an impaired older person. [ABSTRACT FROM AUTHOR]

The objective of this study is to examine the influences of gender on long-term care service use among older Mexican American widows and widowers. Our analysis is based on a sample of 773 widows and 183 widowers from the Longitudinal Study of Elderly Mexican American Health (H-EPESE). In this sample widows resemble widowers in terms of demographic and health characteristics. However, widows report more financial strain than widowers and a greater welfare dependency (SSI) and Medicaid use. Among those who suffered diminished health, widows were more likely than widowers to use communitybased long-term care services whereas widowers were more likely to enter a nursing home. Widows also had more instrumental and socioemotional support than widowers. Serious cognitive and functional impairment, though, places widows and widowers at the same risk of institutionalization. We end with a discussion of the policy implications of these findings. [ABSTRACT FROM AUTHOR]

As family disruption, violence, and the decline of community become more common, an ever-growing number of children are exposed to psychological and social stressors that can lead to serious emotional problems. For many children emotional problems can interfere with normal psychological and social development and can have serious long-term effects. In this study data from a large national survey are used to examine patterns of emotional and physical comorbidity and the uses of general medical and mental health services by children ages 4 to 11. Results indicate that emotional problems are common among children with physical illnesses and that emotional problems increase general medical care use. Emotional problems are clearly exacerbated by factors associated with poverty. The data also show that a larger proportion of children in single-parent than in two-parent families experience emotional problems and use mental health services. We discuss the implications of these findings for general pediatric practice. [ABSTRACT FROM AUTHOR]

Research shows that social engagement reduces the probability of cognitive decline in late life. The purpose of this study was to test whether religious attendance, a major source of social engagement for many older individuals, is associated with slower rates of cognitive decline among older Mexican Americans. Using four waves of data collected from a sample of 3,050 older Mexican-origin individuals, we estimated a series of linear growth curve models to assess the effects of religious attendance on cognitive functioning trajectories. We used the Mini-Mental State Examination to measure cognitive functioning. Our central finding is that religious attendance is associated with slower rates of cognitive decline among older Mexican Americans. Specifically, respondents who attend church monthly, weekly, and more than weekly tend to exhibit slower rates of cognitive decline than those who do not attend church. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Studies in the area of religion and mortality are based primarily on data derived from samples of predominantly non-Hispanic Whites. Given the importance of religion in the lives of Hispanics living in the United States, particularly older Hispanics, we examine the effects of religious attendance on mortality risk among Mexican Americans aged 65 and older. METHODS: We employ data from the Hispanic Established Populations for Epidemiologic Studies of the Elderly to predict the risk of all-cause mortality over an 8-year follow-up period. RESULT: Overall, the results show that those who attend church once per week exhibit a 32% reduction in the risk of mortality as compared with those who never attend religious services. Moreover, the benefits of weekly attendance persist with controls for sociodemographic characteristics, cardiovascular health, activities of daily living, cognitive functioning, physical mobility and functioning, social support, health behaviors, mental health, and subjective health. DISCUSSION: Our findings suggest that weekly church attendance may reduce the risk of mortality among older Mexican Americans. Future research should focus on identifying other potential mediators of the relationship between religious involvement and mortality risk in the Mexican-origin population. [ABSTRACT FROM AUTHOR]

Background: The purpose of this analysis was to examine the differential impact of performance-based and self-reported lower body measures on 2-year mortality in Mexican American elderly persons.Methods: Data employed are from the Hispanic Established Population for Epidemiological Studies of the Elderly, a probability survey of 3050 community-dwelling Mexican Americans aged 65 and older from the five Southwestern states interviewed in 1993 and 1994. Of the baseline sample with complete data, 198 persons were confirmed deceased 2 years later. A three-task, performance-based, lower body function measure consisting of a short walk, balance, and repeated chair stands tests was used. Self-reported lower body function was measured by a 4-item Activities of Daily Living (ADL) measure involving the lower body.Results: The three-task, lower body function measure was a significant predictor of 2-year mortality. The short walk alone was as predictive as the summary measure. The predictive ability of both measures was minimally reduced by the inclusion of the self-reported ADL measure and life-threatening medical conditions. Finally, the ADL measure was not a significant predictor of mortality with all the other variables in the analysis.Conclusion: Objective measures of lower body function were significant predicators of mortality in Mexican American elderly persons, as found in the general population. Unlike previous studies, the ADL measure was not an independent predictor of mortality after controlling for the objective measure and other risk factors. Additional research is needed to address why objective measures of function are such strong predictors of death. [ABSTRACT FROM AUTHOR]

The pressure-induced structural changes in the perovskite-type (ABO 3 ) ferroelectric solid solution (1-x)Na 0.5 Bi 0.5 TiO 3 -xBaTiO 3 (NBT-xBT) at the morphotropic phase boundary (MPB) ( x MPB = 0.048 ) have been analyzed up to 12.3 GPa by single-crystal x-ray diffraction with synchrotron radiation. A pressure-induced phase transition takes place between 4.4 and 5.0 GPa, where the pseudocubic low-pressure phase transforms into an orthorhombic high-pressure phase with space group Pnma. The high-pressure phase is comprised of mixed BO 6 tilts and anti-polar A-cation displacements, without exhibiting coherent off-centered shifts of the B-site Ti 4 + cations that can be detected by synchrotron x-ray diffraction. Our results reveal that at ambient pressure and room temperature the NBT- x MPB BT structure possesses anti-phase BO 6 tilts with a relatively large correlation length and the same type of polar distortions as those present in pure NBT, but with strongly violated correlation length due to Ba 2 + -induced local elastic-stress fields. For x MPB the effect of Ba on the mesoscopic-scale structure is compensated by a mild external pressure of only 0.7 GPa, resulting in structural features resembling those of pure NBT at ambient conditions., (© 2024. The Author(s).)

Competing Interests: None.

Characterizing the pressure and temperature ( P-T ) histories of eclogite facies rocks is of key importance for unravelling subduction zone processes at all scales. Accurate P-T estimates provide constraints on tectonic and geochemical processes affecting subduction dynamics and help in interpreting the geophysical images of present-day converging plates. Conventional equilibrium geothermobarometers are challenged in ultra high pressure (UHP) metamorphic terranes, as minerals may undergo re-equilibration along their exhumation path. Elastic geobarometry applied to host-inclusion systems is a complementary method to determine P-T conditions of metamorphism independent from chemical equilibrium. Because only a single measurement, the inclusion strain, is made, only a line in P-T space of possible entrapment conditions, the entrapment isomeke, can be determined. Thus, the entrapment pressure along an isomeke can only be determined if the entrapment temperature is known. An alternative is to calculate entrapment conditions for two types of inclusions that are believed, from petrological evidence such as being in the same garnet growth zone, to have been entrapped at the same time. The intersection between the two sets of isomeke calculated on multiple quartz and zircon inclusions demonstrates that measuring different inclusion phases trapped inside a single host allows unique P-T conditions for the host rock to be determined. Here, we combine Zr-in-Rutile thermometry and thermodynamic modelling with micro-Raman measurements on quartz and zircon inclusions trapped in garnet to obtain pressures and temperatures of equilibration of a quartz-garnet vein from the Proterozoic Ulla gneiss basement and of garnet-kyanite gneiss from the Caledonian Blåhø nappe, both in the Fjørtoft UHP terrane, Norway. We find that the quartz-garnet vein formed at high pressure (1.5-2.5 GPa and 750-800°C) and recrystallized at ~1.2 GPa and 880°C. In contrast, the garnet-kyanite gneiss followed an anticlockwise path with peak P-T at 1.2 GPa and 880°C: these estimates are consistent with previous thermodynamic modelling and suggest that the Ulla gneiss and the Blåhø nappe came into contact at these last conditions. We also discuss a new method to detect hydrostatic versus Non-hydrostatic stresses near quartz and zircon inclusions in garnet., (© 2021 The Authors. Journal of Metamorphic Geology published by John Wiley & Sons Ltd.)

Context: States face increasing Medicaid expenditures largely as a result of growing dual-eligible populations. In this article we examine self-reported community-based Medicaid participation among Medicare recipients 65 and older in California and Texas, with a particular focus on the older Mexican-origin population., Methods: We use six waves of the Hispanic Established Populations for the Epidemiologic Study of the Elderly (H-EPESE) covering the period from 1993-94 to 2010-11., Findings: The data reveal relatively high Medicaid participation rates by older individuals of Mexican origin, but significant differences between the two states. At baseline, 30% of older Mexican-origin Medicare beneficiaries in California reported receiving Medicaid compared to 41% in Texas., Conclusions: Despite California's more liberal eligibility criteria, community-dwelling Texans were more likely than Californians to report coverage at some point during the 17-year follow-up. Our data, as well as administrative data, reveal that California classifies nearly all of its community-dwelling Medicaid recipients as "full duals," meaning that they receive full benefits, whereas Texas is more likely to classify similarly poor and disabled individuals as "partial duals," meaning that they receive less coverage, thereby lowering overall program expenditures. Cost containment strategies that restrict access may be especially consequential for vulnerable Hispanic populations., (Copyright © 2019 by Duke University Press.)

The unique physical, cultural, and ecological location of U.S. American Indian reservations simultaneously presents risks for mental health and offers sources of resilience to Native peoples. Using survey data from two American Indian tribes, we explore whether the length of one's life spent on a reservation is associated with lower odds of psychological distress. In both tribes, we find that individuals who live a vast majority of their lives on the reservation have lower odds of psychological distress than individuals who spent portions of their life off or near the reservation. These findings suggest a need to reframe the perception of life experience on tribal reservations but also call for a more nuanced investigation of the life experience of American Indians. This study illustrates the importance of deeply exploring the relationship that American Indians have with their tribal reservation lands.

Density-functional theory (DFT) calculations incorporating a pairwise dispersion correction were employed to optimize the structures of various neutral-framework compounds with zeolite topologies. The calculations used the PBE functional for solids (PBEsol) in combination with two different dispersion correction schemes, the D2 correction devised by Grimme and the TS correction of Tkatchenko and Scheffler. In the first part of the study, a benchmarking of the DFT-optimized structures against experimental crystal structure data was carried out, considering a total of 14 structures (8 all-silica zeolites, 4 aluminophosphate zeotypes, and 2 dense phases). Both PBEsol-D2 and PBEsol-TS showed an excellent performance, improving significantly over the best-performing approach identified in a previous study (PBE-TS). The temperature dependence of lattice parameters and bond lengths was assessed for those zeotypes where the available experimental data permitted such an analysis. In most instances, the agreement between DFT and experiment improved when the experimental data were corrected for the effects of thermal motion and when low-temperature structure data rather than room-temperature structure data were used as a reference. In the second part, a benchmarking against experimental enthalpies of transition (with respect to α-quartz) was carried out for 16 all-silica zeolites. Excellent agreement was obtained with the PBEsol-D2 functional, with the overall error being in the same range as the experimental uncertainty. Altogether, PBEsol-D2 can be recommended as a computationally efficient DFT approach that simultaneously delivers accurate structures and energetics of neutral-framework zeotypes.

Copper(I) iodine compounds can exhibit interesting mechanochromic and thermochromic luminescent properties with important technological applications. We report the synthesis and structure determination by X-ray diffraction of a new polymeric staircase copper(I) iodine compound catena(bis(μ2-iodo)-6-methylquinoline-copper(I), [C10H9CuIN]. The structure is composed of isolated polymeric staircase chains of copper-iodine coordinated to organic ligands through Cu-N bonds. High pressure X-ray diffraction to 6.45 GPa shows that the material is soft, with a bulk modulus K0 = 10.2(2)GPa and a first derivative K'0 = 8.1(3), typical for organometallic compounds. The unit-cell compression is very anisotropic with the stiffest direction [302] arising from a combination of the stiff CuI ladders and the shear of the planar quinolone ligands over one another. Full structure refinements at elevated pressures show that pressures reduce the Cu···Cu distances in the compound. This effect is detected in luminescence spectra with the appearance of four sub-bands at 515, 600, 647, and 712 nm above 3.5 GPa. Red-shifts are observed, and they are tentatively associated with interactions between copper(I) ions due to the shortening of the Cu···Cu distances induced by pressure, below twice the van der Waals limit (2.8 Å). Additionally, ab initio simulations were performed, and they confirmed the structure and the results obtained experimentally for the equation of state. The simulation allowed the band structure and the electronic density of states of this copper(I) iodine complex to be determined. In particular, the band gap decreases slowly with pressure in a quadratic way with dEg/dP = -0.011 eV/GPa and d(2)Eg/dP(2) = 0.001 eV/GPa(2).

Objective: This study examines the potential effects of nativity and acculturation on active life expectancy (ALE) among Mexican-origin elders., Method: We employ 17 years of data from the Hispanic Established Population for the Epidemiologic Study of the Elderly to calculate ALE at age 65 with and without disabilities., Results: Native-born males and foreign-born females spend a larger fraction of their elderly years with activities of daily living (ADL) disability. Conversely, both foreign-born males and females spend a larger fraction of their remaining years with instrumental activities of daily life (IADL) disability than the native-born. In descriptive analysis, women with low acculturation report higher ADL and IADL disability. Men manifest similar patterns for IADLs., Discussion: Although foreign-born elders live slightly longer lives, they do so with more years spent in a disabled state. Given the rapid aging of the Mexican-origin population, the prevention and treatment of disabilities, particularly among the foreign born, should be a major public health priority., (© The Author(s) 2015.)

Objectives: (a) To identify factors associated with different patterns of functional decline in a longitudinal sample of older Mexican-origin individuals, and (b) to determine the proportions of life after age 65 characterized by serious functional impairment., Methodology: We use the Hispanic Established Populations for Epidemiologic Studies of the Elderly to examine changes in objective Performance Oriented Mobility Assessments in a cohort of 3,050 Mexican-origin elders initially interviewed in 1993/1994 and recontacted 6 times over 17 years. This sample combined with an additional cohort of 902 individuals 75 and older added at wave 4 in 2004/2005 (combined sample = 3,952) is used in life table analyses to estimate the number of years after 65 characterized by serious functional impairment., Results: Three distinct patterns of functional decline emerge: (a) high initial functioning followed by decline, but not to the level of disability (48%); (b) moderate initial functioning followed by decline to the level of disability (37.5%); and (c) initial disability followed by continued poor functioning (14.5%). Life table analyses reveal that subjects spent over half of the period after 65 with serious functional limitations. Significant gender and nativity differentials emerge., Discussion: Protracted morbidity that accompanies increases in life expectancy has serious implications for the physical, social, and economic well-being of older individuals and their families, as well as for health and long-term care policy., (© The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Much like other racial/ethnic groups, Latinos are facing challenges to provide needed care to aging adults. Older Latinos underutilize nursing homes and home health care services and primarily rely on their families for assistance. While this general trend has been established, little attention has been paid to nativity differentials in patterns of caregiving for this segment of the aging population. The analyses are based on the latest wave (Wave 7) of the Hispanic Established Population for Epidemiologic Studies of the Elderly or H-EPESE (2010/2011) a sample of older Mexican-origin adults and their family caregivers living in the southwestern U.S. We examine 629 child caregiver/parent care recipient dyads using bivariate statistics and multinomial logistic regression analyses. The results reveal that while grown children of Mexican-origin elders play a critical role in providing instrumental and financial supports to their aging parents, the burden that the children of foreign-born parents bear is greater. Despite higher rates of disability, Mexican-born elders are more dependent on a child for help and far less likely to call upon other family members, relatives and community based-providers for help than the U.S. born. Given the recent and future growth of older Latinos, intervention strategies will need to focus on nativity status and acculturative processes in the context of caregiving and caregiver burden.

The rapid growth in comparative survey research carried out in multiple countries, or among different language communities within a single nation, has given rise to a renewed concern with problems of translation. The fundamental problem facing the comparative survey researcher relates to the complexity and subjectivity of language, and the fact that complete equivalence of concepts in different linguistic, cultural, and social class contexts may be in principle impossible to achieve. Yet language remains the only medium through which information concerning subjective states, values, and beliefs can be collected. That language and the subjective constructs to which it refers are influenced by a wide range of cultural and social factors. This fact has particular relevance for comparative aging research since older individuals are often monolingual in their native languages and more tied to traditional cultures than younger individuals. This paper consists of a review of basic issues related to the nature of language and communication, and discusses the possibility of a truly scientific translation process. It outlines current best practices, and also raises questions related to the common practice of using information collected with translated survey instruments in ways that assume it reflects a comparable and quantifiable latent construct.

The pressure-induced phase transition sequence in PbSc(0.5)Ta(0.5)O(3) (PST) and PbSc(0.5)Nb(0.5)O(3) (PSN) heavily doped with homo- and heterovalent cations on the A- or B-site of the perovskite-type structure (ABO(3)) was analysed by in situ synchrotron x-ray diffraction and Raman spectroscopy up to pressures of 25 GPa. We focused on the structural phenomena occurring above the first pressure-induced phase transition at p(c1) from a relaxor state to a non-polar rhombohedral phase with antiphase tilting of the BO(6) octahedra. The samples studied were PST doped with Nb(5+) and Sn(4+) on the B-site, PST doped with Ba(2+) and La(3+) on the A-site and PSN doped with Sr(2+) and La(3+) on the A-site. All of them exhibit a second pressure-induced phase transition at p(c2), similar to pure PST and PSN. The second transition involves the development of either order of antiparallel Pb(2+) displacements and complementary a(+)b(-)b(-) octahedral tilts, or a(-)b(-)b(-) (0 ≤ a < b) tilting alone. As in pure PST and PSN, the second phase transition is preceded by the occurrence of unequal octahedral tilts on the local scale. The substitution of Nb(5+) for Ta(5+) as well as the coupled substitution of Sn(4+) for Sc(3+) + Ta(5+) on the octahedral B sites increases the second critical pressure. The doping by Nb(5+) also reduces the length of coherence of antipolar Pb(2+) order developed at p(c2). The isovalent substitution of the larger Ba(2+) for Pb(2+) on the A-site suppresses the antipolar Pb(2+) order due to the induced local elastic stresses and thus significantly increases p(c2). The substitution of smaller cations for Pb(2+) on the A-site generally favours the development of long-range order of antiparallel Pb(2+) displacements because of the chemically enhanced a(-)a(-)a(-) octahedral tilts. However, this ordering is less when the dopant is aliovalent, due to the charge imbalance on the A-site. For all of the relaxors studied here, the dynamic compressibility estimated from the pressure derivative of the wavenumber of the soft mode associated with the first phase transition is larger in the pressure interval between p(c1) and p(c2) than above p(c2). The dynamic compressibility of the phase above p(c2) decreases if the antipolar Pb(2+) order is disturbed.

Unlabelled: BACKGROUND/STUDY CONTEXT: Physical performance measures have been found to be strong predictors of adverse outcomes in aging populations. Few studies have examined the predictive ability of physical performance measures exclusively within populations of the very old. This study explores the predictive ability of the Short Physical Performance Battery (SPPB) and its three subcomponents-a timed walk, balance test, and repeated timed chair stands-on mortality in a sample of Mexican Americans aged 75 and older., Methods: Logistic regression analyses were used with data from the Hispanic Established Population for the Epidemiological Study of the Elderly (Hispanic EPESE), to investigate the relationship between timed walk, balance test, repeated timed chair stands, and the SPPB and mortality over a 2½-year period., Results: The authors find that being unable to complete the timed walk, the balance test, and repeated timed chair stands, or unable to complete any of the SPPB was significantly associated with mortality over 2½ years., Conclusion: These findings indicate that physical performance measures may be less predictive of short-term mortality in very old Mexican Americans than previously thought. More research is needed to understand this relationship.

The crystal structures for the three perovskites, CaSnO(3), YAlO(3), and LaAlO(3), were geometry optimized at the density functional theory level for a wide range of simulated isotropic pressures up to 80 GPa. The connections between the geometry optimized bond lengths, R(M-O), the values of the electron density, ρ(r(c)), the local kinetic, G(r(c)), potential, V(r(c)), energy densities, H(r(c)), and the Laplacian, ∇(2)(r(c)), at the bond critical points, r(c), for the M-O nonequivalent bonded interactions were examined. With increasing pressure, ρ(r(c)) increases along four distinct trends when plotted in terms of the Al-O, Ca-O, Sn-O, Y-O, and La-O bond lengths, but when the bond lengths were plotted in terms of ρ(r(c))/r where r is the periodic table row number of the M atoms, the data scatter along a single trend modeled by the power law regression expression R(M-O) = 1.41(ρ(r(c))/r)(-0.21), an expression that is comparable with that obtained for the bonded interactions for a large number of silicate and oxides crystals, R(M-O) = 1.46(ρ(r(c))/r)(-0.19) and that obtained for a relatively large number of hydroxyacid molecules R(M-O) = 1.39(s/r)(-0.22) where s is the Pauling bond strength of a bonded interaction. The similarity of the expressions determined for the perovskites, silicate and oxides crystals, and hydroxyacid molecules suggest that the bonded interactions in molecules and crystal are not only similar and comparable. The close correspondence of the expressions for the perovskites, the silicate and oxide crystals, and the molecules indicates that Pauling bond strength and ρ(r(c)) are comparable measures of the bonded interactions, the larger the accumulation of the electron density between the bonded atoms the larger the value of s, the shorter the bond lengths. It also indicates that the bonded interactions that govern the bond length variations behave as if largely short ranged. Like ρ(r(c))/r, the values of G(r(c))/r, V(r(c))/r, ∇(2)(r(c))/r likewise correlate in terms of R(M-O) in a single trend. With increasing pressure, the value of V(r(c)) decreases at a faster rate than G(r(c)) increases consistent with the observation that ρ(r(c)) increases with increasing pressure thereby stabilizing the structures at high pressures. As evinced by the well-developed power law trends between R(M-O) and the bond critical point properties, the bulk of the bonded interactions for the perovskites are concluded to change progressively from closed-shell to intermediate polar covalent interactions with increasing pressure. A well-developed trend between the ratios ∣V(r(c))∣ /G(r(c)) and H(r(c))/ρ(r(c)) is consistent with this conclusion. The employment of a positive value for the Laplacian alone in distinguishing between closed shell and polar covalent bonded interactions is unsatisfactory when 2G(r(c)) > ∣V(r(c))∣ > G(r(c)).

We employ two surveys to identify similarities and differences in the risk of abuse among poor urban Mexican-origin women in the United States and Mexico. While the two surveys reveal basic structural similarity in the predictors of partner violence, the rate of violence among Mexican women is far lower than among either foreign-born or native-born Mexican origin women in the United States. While these differences may reflect reality, we argue that survey data must be interpreted cautiously and with an understanding of the cultural, economic, and political context in which the information is collected as well as methodological differences between the surveys.

The structural evolution of orthorhombic CaTiO3 perovskite has been studied using high-pressure single-crystal x-ray diffraction under hydrostatic conditions up to 8.1 GPa and under a non-hydrostatic stress field formed in a diamond anvil cell (DAC) up to 4.7 GPa. Under hydrostatic conditions, the TiO6 octahedra become more tilted and distorted with increasing pressure, similar to other 2:4 perovskites. Under non-hydrostatic conditions, the experiments do not show any apparent difference in the internal structural variation from hydrostatic conditions and no additional tilts and distortions in the TiO6 octahedra are observed, even though the lattice itself becomes distorted due to the non-hydrostatic stress. The similarity between the hydrostatic and non-hydrostatic cases can be ascribed to the fact that CaTiO3 perovskite is nearly elastically isotropic and, as a consequence, its deviatoric unit-cell volume strain produced by the non-hydrostatic stress is very small; in other words, the additional octahedral tilts relevant to the extra unit-cell volume associated with the deviatoric unit-cell volume strain may be totally neglected. This study further addresses the role that three factors--the elastic properties, the crystal orientation and the pressure medium--have on the structural evolution of an orthorhombic perovskite loaded in a DAC under non-hydrostatic conditions. The influence of these factors can be clearly visualized by plotting the three-dimensional distribution of the deviatoric unit-cell volume strain in relation to the cylindrical axis of the DAC and indicates that, if the elasticity of a perovskite is nearly isotropic as it is for CaTiO3, the other two factors become relatively insignificant.

The decoding of the human genome and advances in genetic medicine promise great advances in the prevention and treatment of disease. These powerful methodologies, though, raise serious intellectual, ethical, and practical questions when they are employed in explanations of complex higher-order behavioral and social outcomes. There can be little doubt that all human behavior reflects complex gene/environment interactions, but isolating the unique contributions of genes and environment in the explanation of overdetermined behavioral and social outcomes may not in principle be possible. When dealing with groups that differ significantly in histories of discrimination and exclusion biological explanations must be employed with caution even as they promise great strides in dealing with specific diseases., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The exceptional properties of lead-based perovskite-type (ABO(3)) relaxor ferroelectrics are due to their structural inhomogeneities. At ambient conditions, the average structure is pseudocubic but rich in ferroic nanoregions too small to be directly studied by conventional diffraction analysis. However, combining in situ temperature and pressure diffraction and Raman scattering allows us to resolve the structural complexity of relaxors. Because of the different length and time scales of sensitivity, diffraction probes the long-range order, i.e., the structure averaged over time and space, whereas Raman spectroscopy can detect local structural deviations from the average structure via the anomalous Raman activity of the phonon modes that, when the symmetry of the average structure is considered, should not generate Raman peaks. Hence, the combined analysis of the long-range order induced at low temperatures or high pressures and of the phonon anomalies enhanced on temperature decrease or pressure increase can reveal the energetically preferred structural nanoclusters existing at ambient conditions. In this regard, high-pressure experiments are vital for understanding the nanoscale structure of relaxors. Using X-ray diffraction, neutron diffraction, and Raman scattering on stoichiometric and doped PbSc(0.5)Ta(0.5)O(3) and PbSc(0.5)Na(0.5)O(3), we demonstrate the existence of a pressure-induced cubic-to-rhombohedral continuous phase transition. The high-pressure structure has suppressed polar shifts of B-site cations, enhanced correlation of Pb-O ferroic species, and long-range ordered antiphase BO(6) octahedral tilts. The critical pressure is preceded by an intermediate pressure at which the coupling between off-centered Pb and B-cations is suppressed and octahedral tilting detectable by neutron diffraction is developed.

The structures of tilted perovskites in each of the 15 tilt systems have been decomposed into the amplitudes of symmetry-adapted modes in order to provide a clear and unambiguous definition of the tilt angles. A full expression in terms of the mode amplitudes for the ratio of the volumes of the two polyhedra within the perovskite structure for each of the 15 tilt systems is derived, along with more general expressions in terms of either mode amplitudes or tilt angles that can be used to estimate this ratio when the distortions of the octahedra are small.

The structural variation of LaAlO(3) perovskite under non-hydrostatic stress developed in the pressure medium within a diamond-anvil cell was determined using single-crystal x-ray diffraction. The experimental results show that the lattice of LaAlO(3) becomes more distorted and deviates from the hydrostatic behavior as pressure is increased up to 7.5 GPa. The determination of the crystal structure further confirms that the octahedral AlO(6) groups become more distorted, but the octahedral rotation around the threefold axis decreases as under hydrostatic conditions. These experimental results can be reproduced from knowledge of the elastic tensor of the sample at ambient conditions and the stress state within the pressure medium. Further calculations for two other orientations also indicate that non-hydrostatic stress has only a small effect on the rotation of the AlO(6) octahedra towards zero, but non-hydrostatic stress inevitably leads to distortions in the crystal lattice and the AlO(6) octahedra. As a result, the crystal structure is eventually driven away from cubic symmetry under non-hydrostatic conditions, whereas it evolves towards cubic symmetry under hydrostatic pressure., (© 2011 IOP Publishing Ltd)

A direct comparison between two complete intensity datasets, collected on the same sample loaded in two identical diamond-anvil pressure cells equipped, respectively, with beryllium and diamond-backing plates was performed. The results clearly demonstrate that the use of diamond-backing plates significantly improves the quality of crystal structure data. There is a decrease in the internal R factor for averaging, structure refinement agreement factors, and in the errors and uncertainties of the atomic coordinates, atomic displacement parameters, and individual bond lengths.

The transition between 190 and 200 K in [Ni(H(2)O)(6)](NO(3))(2)·(15-crown-5)·H(2)O has been followed by determining the structure at 22 temperatures in the range 90-273 K. The structural change is a zone-boundary transition with a critical point at (½, 0, ½) in the Brillouin zone of the high-temperature phase; both phases have space-group symmetry P2(1) but the volume of the unit cell is halved when a crystal is heated through the transition. The only obvious disorder in the high-temperature phase is of the lattice water molecule, which occupies two sites; some disorder persists below the transition. The greatest changes in the structure below the transition are the rotations of one of the two 15-crown-5 molecules and of one of the two nitrate ions; above the transition the two molecules are related by symmetry as are the two ions. Below the transition these two rotation angles evolve linearly with one another, and can thus be associated with a single order parameter that describes the structural evolution. The evolution of the spontaneous strain arising from the transition does not, however, follow the same evolution as the structural order parameter. This observation indicates that the transition cannot be described in terms of a Landau-type expansion that is characterized by a single order parameter, perhaps because the potential-energy surface for this essentially molecular crystal is more complicated than for the inorganic and framework structures in which such simple behaviour is observed., (© 2011 International Union of Crystallography)

The structural evolution of PbSc(0.5)Nb(0.5)O(3) (PSN) under pressure has been studied by in situ powder neutron diffraction. Rietveld refinements to the data show that the continuous phase transition detected by x-ray diffraction at p(c) = 4.1 GPa (Maier et al 2010 Phys. Rev. B 81 174116) is associated with long-range ordering of antiphase octahedral tilts and local ordering of ferroic Pb displacements. Similar to PbSc(0.5)Ta(0.5)O(3) (PST) (Maier et al 2010 Acta Crystallogr. 66 280-91), antiphase octahedral tilting even exists below the critical pressure in a regime in which the structure retains a cubic metric. In contrast to PST, in which the Pb atomic displacement parameters (DPs) form ellipsoids elongated along the cubic {111} directions, the atomic DPs of Pb in PSN form flattened discs parallel to the cubic {111}-planes. This indicates that in PST the Pb displacements are along the cubic {111} directions, whereas in PSN the local Pb displacements are randomly distributed along the cubic {110} directions. The latter can be explained by the abundance of underbonded oxygen atoms associated with the chemical B-site disorder.

Introduction: largely a consequence of historical gender differences in labor force attachment in the United States, many women rely on their spouse for health insurance coverage, particularly during late middle age. Prior research finds that this creates a window of vulnerability for women during late middle age who may lose their (older) spouse's employment-based coverage when he retires from the labor force and enrolls in Medicare. However, the few studies that have examined this window of vulnerability have been based primarily on white adults., Methods: we used the 2004 and 2006 Annual Social and Economic Supplements to the Current Population Survey to examine whether the window of vulnerability exists among non-Hispanic Black, Mexican-origin, and non-Hispanic White women 55 to 64 years of age, and whether similar factors contribute to the vulnerability across these race/ethnic groups., Results: women 55 to 64 years of age married to men 65 years or older had an elevated risk of lacking coverage at a time of life when health problems are common and expensive. Among non-Hispanic White women, their husband's exit from full-time employment accounted for the higher risk, whereas a more complex and systemic set of social factors contributed to the higher risk among non-Hispanic Black and Mexican-origin women., Conclusion: ensuring adequate and affordable health insurance coverage among women during late middle age may require additional health care reforms such as extending Medicare eligibility to younger adults or basing Medicare age eligibility on the age of the older partner within a married couple., (2011 Jacobs Institute of Women's Health. Published by Elsevier Inc.)

Objective: In this article, we investigate the association between age at migration and mortality during a 13-year period in a sample of Mexican American immigrants 65 and older at baseline., Method: We employ the Hispanic Established Populations for Epidemiologic Studies of the Elderly (H-PESE) to control for mortality-related health and social factors., Results: Our analyses show that the immigrant generation does not represent a homogeneous mortality risk category. Individuals who migrated to the United States in mature adulthood have a considerably lower risk of death than individuals who migrated in childhood or midlife. Chronic conditions or functional capacity do not account for these differences., Conclusion: Our findings suggest that standard risk pools may differ significantly on the basis of genetic and unmeasured life-course factors. A better understanding of the late-life immigrant mortality advantage has important implications for more effective and targeted social and medical interventions.

Context: Mexico., Purpose: Using the health care service utilization model as a framework, this paper will analyze the differences in health care service use among older Mexicans living in urban and rural areas in Mexico., Methods: The Mexican Health and Aging Survey (MHAS) data were used to test the applicability of Andersen's "model of health services" of predisposing (ie, age, sex, etc.), enabling (education, insurance coverage, etc.) and need factors (diabetes, hypertension, etc.) to predict ever being in the hospital and physician visits in the past year by place of residence (urban, rural, semi-rural)., Findings: Results showed that older Mexicans living in the most rural areas (populations of 2,500 or fewer) were significantly less likely to have been hospitalized in the previous year and visited the physician less often (P < .0001) than their urban counterparts. The significant difference in hospitalization between rural and urban residing older Mexicans was largely accounted for by having health care coverage. Certain need factors such as diabetes, previous heart attack, hypertension, depression, and functional limitations predicted frequency of physician visits and hospitalization, but they did not explain variations between rural and urban older Mexicans., Conclusions: Not having insurance coverage was associated with a lower likelihood of spending an overnight visit in the hospital and visiting a physician for older Mexicans. This lower utilization may be due to barriers to access rather than better health., (© 2010 National Rural Health Association.)

We have employed a combination of powder neutron diffraction and single-crystal synchrotron X-ray diffraction to characterize the pressure-induced phase transitions that occur in the perovskite-type relaxor ferroelectric PbSc(0.5)Ta(0.5)O(3) (PST) and Pb(0.78)Ba(0.22)Sc(0.5)Ta(0.5)O(3) (PST-Ba). At ambient pressure the symmetry of the average structure for both compounds is Fm3m as a result of partial ordering of the Sc and Ta cations on the octahedral sites. At pressures above the phase transition both the neutron and X-ray diffraction patterns exhibit an increase in the intensities of h,k,l = all odd reflections and no appearance of additional Bragg reflections. Synchrotron single-crystal X-ray diffraction data show that the intensity of hhh peaks, h = 2n + 1, does not change with pressure. This indicates that the structural distortion arising from the phase transition has a glide-plane pseudo-symmetry along the 111 cubic directions. Rietveld refinement to the neutron powder data shows that the high-pressure phase has either R3c or R3 symmetry, depending on whether the presence of 1:1 octahedral cation ordering is neglected or taken into account, and comprises octahedral tilts of the type a(-)a(-)a(-) that continuously evolve with pressure. The cubic-to-rhombohedral transition is also marked by a large increase in the anisotropy of the displacement ellipsoids of the Pb cations, indicating larger displacements of Pb cations along the rhombohedral threefold axis rather than within the perpendicular plane. For PST the anisotropy of the Pb displacement parameters decreases at approximately 3 GPa above the phase-transition pressure. For both PST and PST-Ba the average magnitudes of Pb-cation displacements expressed in terms of isotropic displacement ellipsoids gradually decrease over the entire pressure range from ambient to 7.35 GPa.

OBJECTIVES: The employment based health insurance system of the United States means that those individuals who are disadvantaged in the labor market are also disadvantaged in terms of health insurance coverage. The Mexican-origin population has historically been disadvantaged in both domains. We examine the extent to which low rates of health insurance coverage among Mexican-origin adult male workers are the result of overrepresentation in the types of employment in which coverage is low for everyone. METHODS: We use logistic regression models to analyze data from 80,827 employed Mexican-origin, African American, and non-Hispanic white men in the 2004 and 2006 Current Population Surveys. RESULTS: The results suggest that although such overrepresentation contributes to low rates of coverage among Mexican-origin workers, even within employment sectors, industries, and occupations Mexican-origin workers are less likely to have coverage than non-Hispanic whites or African Americans. CONCLUSIONS: These results make it clear that the health insurance vulnerabilit y of the Mexican-origin population reflects multiple barriers to coverage in addition to those related to employment.

Objectives: We examined the long-term health consequences of relationship violence in adulthood., Methods: Using data from the Welfare, Children, and Families project (1999 and 2001), a probability sample of 2402 low-income women with children living in disadvantaged neighborhoods in Boston, Massachusetts; Chicago, Illinois; and San Antonio, Texas, we predicted changes in the frequency of intoxication, psychological distress, and self-rated health over 2 years with baseline measures of relationship violence and a host of relevant background variables., Results: Our analyses showed that psychological aggression predicted increases in psychological distress, whereas minor physical assault and sexual coercion predicted increases in the frequency of intoxication. There was no evidence to suggest that relationship violence in adulthood predicted changes in self-rated health., Conclusions: Experiences with relationship violence beyond the formative and developmental years of childhood and adolescence can have far-reaching effects on the health status of disadvantaged urban women.

The evolution of the crystal structure of rhombohedral PrAlO(3) perovskite with pressure has been investigated by single-crystal x-ray diffraction and Raman scattering experiments. The structural evolution as indicated by lattice strains, octahedral tilts, and the distortions of the octahedral AlO(6) and polyhedral PrO(12) groups with increasing pressure, is controlled by the relative compressibilities of the AlO(6) octahedra and the PrO(12) site. Because the AlO(6) octahedra are more compressible than the PrO(12) sites, up to 7.4 GPa the structure evolves towards the high-symmetry cubic phase like any other rhombohedral perovskite. The variation of volume of the rhombohedral phase with pressure can be represented by a third-order Birch-Murnaghan equation of state with bulk modulus K(0) = 193.0(1.2) GPa and K' = 6.6(4). Above 7.4 GPa the evolution towards a cubic phase is interrupted by a phase transition. Observations are consistent with the assignment of Imma symmetry to the high-pressure phase. Comparison with the low-temperature [Formula: see text] to Imma transition confirms that electronic interactions stabilize the Imma phase.

In the United States, a woman health insurance coverage is largely determined by her employment and marital roles. This research evaluates competing hypotheses regarding how the combination of employment and marital roles shapes insurance coverage among Mexican-origin, non-Hispanic white, and African American women. We use data from the 2004 and 2006 March Supplements to the Current Population Surveys. Results show that these roles largely substitute for each other among non-Hispanic white and African American women, although marriage generally increases the odds of coverage slightly more than employment among non-Hispanic white women. In contrast, these roles cumulatively increase those odds among Mexican-origin women. Yet neither employment, nor marriage, nor their combination assures their coverage. Married Mexican-origin women are particularly disadvantaged. As women increasingly spend a smaller fraction of their lives in marriage, and as relatively few women are in benefits-rich occupations, stable and equitable coverage may require a universal health insurance system.