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Toric focal conic domains (TFCDs) in smectic liquid crystals exhibit distinct topological characteristics, featuring torus-shaped molecular alignment patterns with rotational symmetry around a central core. TFCDs have attracted much interest due to their unique topological structures and properties, enabling not only fundamental studies but also potential applications in liquid crystal (LC)-based devices. Here, we investigated the precise spatial control of the arrangement of TFCDs using micropatterns and sublimation of TFCDs to estimate the energy states of the torus-like structures. Through simulations, we observed that the arrangement of TFCDs strongly depends on the shape of the topographies of underlying substrates. To accurately estimate the energetic effects of non-zero eccentricity and evaluate their thermodynamic stability, we propose a geometric model. Our findings provide valuable insights into the behavior of smectic LCs, offering opportunities for developing novel LC-based devices with precise control over their topological properties.
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BACKGROUND: On August 5, 2015, the Gold King Mine Spill (GKMS) resulted in 3 million gallons of acid mine drainage spilling into the San Juan River impacting the Diné Bikeyah (traditional homelands of the Navajo people). The Gold King Mine Spill Diné Exposure Project was formed to understand the impacts of the GKMS on the Diné (Navajo). Reporting individualized household results in an exposure study is becoming more common; however, materials are often developed with limited community input with knowledge flowing in one direction - from researcher to participant. In this study we examined the development, dissemination, and evaluation of individualized results materials. METHODS: In August 2016, Navajo Nation Community Health Representatives (Navajo CHRs) sampled household water, dust, and soil, and resident blood and urine for lead and arsenic, respectively. From May-July 2017, iterative dialogue with a wide range of community partners and a community focus groups guided the development of a culturally-based dissemination process. In August 2017, Navajo CHRs reported individualized results and they surveyed the participants on the report-back process at that time. RESULTS: All of the 63 Diné adults (100%) who participated in the exposure study received their results by a CHR in person and 42 (67%) completed an evaluation. Most of those participants (83%) were satisfied with the result packets. Respondents ranked the individual and overall household results as the most important information they received (69% and 57%, respectively), while information on metals exposures and their health effects were the least helpful. CONCLUSIONS: Our project illustrates how a model of environmental health dialogue, defined by iterative, multidirectional communication among Indigenous community members, trusted Indigenous leaders, Indigenous researchers, non-Indigenous researchers, can improve reporting individualized study results. Findings can inform future research to encourage multi-directional environmental health dialogue to craft more culturally responsive and effective dissemination and communication materials.
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Ouro , Indígenas Norte-Americanos , Humanos , Exposição Ambiental/análise , Saúde Ambiental , Saúde PúblicaRESUMO
Personal exposure studies suffer from uncertainty issues, largely stemming from individual behavior uncertainties. Built on spatial-temporal exposure analysis and methods, this study proposed a novel approach to spatial-temporal modeling that incorporated behavior classifications taking into account uncertainties, to estimate individual livestock exposure potential. The new approach was applied in a community-based research project with a Tribal community in the southwest United States. The community project examined the geospatial and temporal grazing patterns of domesticated livestock in a watershed containing 52 abandoned uranium mines (AUMs). Thus, the study aimed to 1) classify Global Positioning System (GPS) data from livestock into three behavior subgroups - grazing, traveling or resting; 2) calculate the daily cumulative exposure potential for livestock; 3) assess the performance of the computational method with and without behavior classifications. Using Lotek Litetrack GPS collars, we collected data at a 20-minute-interval for 2 flocks of sheep and goats during the spring and summer of 2019. Analysis and modeling of GPS data demonstrated no significant difference in individual cumulative exposure potential within each flock when animal behaviors with probability/uncertainties were considered. However, when daily cumulative exposure potential was calculated without consideration of animal behavior or probability/uncertainties, significant differences among animals within a herd were observed, which does not match animal grazing behaviors reported by livestock owners. These results suggest that the proposed method of including behavior subgroups with probability/uncertainties more closely resembled the observed grazing behaviors reported by livestock owners. Results from the research may be used for future intervention and policy-making on remediation efforts in communities where grazing livestock may encounter environmental contaminants. This research also demonstrates a novel robust geographic information system (GIS)-based framework to estimate cumulative exposure potential to environmental contaminants and provides critical information to address community questions on livestock exposure to AUMs.
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This paper explores how Indigenous-led research reframes the impacts and response to environmental disasters in the context of acid mine spills in rural communities of the Southwest United States. The collaborative research project addressing the Gold King Mine Spill (GKMS) designed qualitative methodologies that center Indigenous worldviews and contribute to broader understandings of environmental justice. The research team, led by Diné scholars and community leaders, gathered qualitative responses from 123 adult participants in twelve focus groups from three rural communities on the Navajo Nation. The project incorporated fluent Diné speakers and cultural consultants to lead focus groups in a manner consistent with cultural worldviews. The analysis of the focus group data resulted in original findings that reframe previous understandings of environmental harm by broadening the boundaries to include: 1) social relations across time; 2) social relations across space; 3) spiritual relations; and 4) restoring balance. The findings allow for greater insight into the colonial context of disaster on rural and Indigenous lands and confronts colonial-rooted disasters through Indigenous-informed political action.
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Nicotine (NIC) and resveratrol (RES) are chemicals in tobacco and wine, respectively, that are widely consumed concurrently worldwide. NIC is an alkaloid known to be toxic, addictive and to produce oxidative stress, while RES is thought of as an antioxidant with putative health benefits. Oxidative stress can induce genotoxic damage, yet few studies have examined whether NIC is genotoxic in vivo. In vitro studies have shown that RES can ameliorate deleterious effects of NIC. However, RES has been reported to have both antioxidant and pro-oxidant effects, and an in vivo study reported that 0.011 mM RES was genotoxic. We used the Drosophila melanogaster wing spot test to determine whether NIC and RES, first individually and then in combination, were genotoxic and/or altered the cell division. We hypothesized that RES would modulate NIC's effects. NIC was genotoxic in the standard (ST) cross in a concentration-independent manner, but not genotoxic in the high bioactivation (HB) cross. RES was not genotoxic in either the ST or HB cross at the concentrations tested. We discovered a complex interaction between NIC and RES. Depending on concentration, RES was protective of NIC's genotoxic damage, RES had no interaction with NIC, or RES had an additive or synergistic effect, increasing NIC's genotoxic damage. Most NIC, RES, and NIC/RES combinations tested altered the cell division in the ST and HB crosses. Because we used the ST and HB crosses, we demonstrated that genotoxicity and cell division alterations were modulated by the xenobiotic metabolism. These results provide evidence of NIC's genotoxicity in vivo at specific concentrations. Moreover, NIC's genotoxicity can be modulated by its interaction with RES in a complex manner, in which their interaction can lead to either increasing NIC's damage or protecting against it.
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OBJECTIVE: Non-invasive assessment of maternal cardiovascular potential and kinetic energy can be used to derive potential-to-kinetic-energy ratio (PKR) and Smith-Madigan inotropic index (SMII), which reflect the balance between blood pressure and blood flow. The aim of this study was to evaluate PKR and SMII in pregnancies complicated by hypertensive disorders of pregnancy (HDP) and/or small-for-gestational-age (SGA) birth. METHODS: This was a prospective study that enrolled women with a singleton pregnancy between 5 and 41 weeks' gestation. Women who developed HDP and/or SGA underwent cardiovascular profiling from 20 weeks. To establish reference ranges for PKR and SMII, women without any pre-existing medical problems at the time of booking who did not develop HDP, SGA or other complications during pregnancy were also recruited for cardiovascular profiling. Measurements of cardiovascular parameters were obtained using a non-imaging ultrasound cardiac output monitor. RESULTS: A total of 688 women completed the study, including 626 controls, 21 cases with HDP, 19 cases with SGA and 22 cases with HDP and SGA. PKR was significantly elevated in pregnancies with placental dysfunction compared with controls (HDP only, 29.81 ± 9.5; HDP and SGA, 44.33 ± 24.27; SGA only, 31.05 ± 13.14; vs controls, 22.30 ± 7.93; all P < 0.05). SMII values were significantly lower only in cases affected by SGA alone when compared with controls (1.47 ± 0.23 W/m2 vs 1.75 ± 0.40 W/m2 ; P < 0.005). These differences remained statistically significant when the analysis was undertaken using multiples of the median values corrected for gestational age. CONCLUSIONS: The findings of this study suggest that point-of-care non-invasive cardiovascular profiling using PKR and SMII may help distinguish between pregnancies affected by specific placental disorders and those exhibiting healthy cardiovascular adaptation to pregnancy. Women with HDP and/or SGA appear to have distinctive PKR and SMII profiles that reflect low kinetic energy in pregnancies with SGA and high potential energy in pregnancies affected by HDP. Finally, non-invasive assessment of potential and kinetic cardiovascular energy demonstrates physiological high-flow and low-resistance adaptation in uncomplicated pregnancies. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.
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Placenta , Pré-Eclâmpsia , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Pré-Eclâmpsia/diagnóstico por imagem , Gravidez , Estudos ProspectivosRESUMO
A coupled phase-field and hydrodynamic model is introduced to describe a two-phase, weakly compressible smectic (layered phase) in contact with an isotropic fluid of different density. A non-conserved smectic order parameter is coupled to a conserved mass density in order to accommodate non-solenoidal flows near the smectic-isotropic boundary arising from density contrast between the two phases. The model aims to describe morphological transitions in smectic thin films under heat treatment, in which arrays of focal conic defects evolve into conical pyramids and concentric rings through curvature dependent evaporation of smectic layers. The model leads to an extended thermodynamic relation at a curved surface that includes its Gaussian curvature, non-classical stresses at the boundary and flows arising from density gradients. The temporal evolution given by the model conserves the overall mass of the liquid crystal while still allowing for the modulated smectic structure to grow or shrink. A numerical solution of the governing equations reveals that pyramidal domains are sculpted at the center of focal conics upon a temperature increase, which display tangential flows at their surface. Other cases investigated include the possible coalescence of two cylindrical stacks of smectic layers, formation of droplets, and the interactions between focal conic domains through flow.
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BACKGROUND: On August 5th, 2015, 3 million gallons of acid mine drainage was accidentally discharged from the Gold King Mine near Silverton, Colorado into Cement Creek which is a tributary to the Animas and San Juan Rivers. The government-initiated risk assessment only assessed a recreational scenario (i.e. hiker drinking from the river), failing to recognize the deep connection of the Diné (Navajo) with the San Juan River. METHODS: Utilizing a mixed-methods approach we determined the impacts of the 2015 Gold King Mine Spill (GKMS or Spill) on Diné activities. We developed a questionnaire to collect pre- and post-GKMS Diné activity frequency and duration. Navajo Nation Community Health Representatives administered the questionnaire to 63 Diné adults and 27 children living in three Navajo communities along the River. RESULTS: Through analysis of the focus group transcripts we identified 43 unique activities between the Diné and San Juan River. There were significant reductions in the total number, frequency, and duration of livelihood, dietary, recreational, cultural/spiritual and arts and craft activities. On average, Diné activities with the San Juan River following the GKMS decreased by 56.2%. SIGNIFICANCE: The significant reduction in activities following the GKMS may lead to long-term trauma, impacting the ability of the Diné to pass down teachings to their children affecting future generations to come. The 43 distinct activities between the Diné and the San Juan River highlight the importance for scientists and disaster responders to consider cultural and spiritual impacts when responding to environmental disasters and conducting risk assessments among Indigenous communities.
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Rios , Poluentes Químicos da Água , Criança , Colorado , Monitoramento Ambiental , Ouro , Humanos , Mineração , Poluentes Químicos da Água/análiseRESUMO
Beginning in 2016, the Agency for Toxic Substances and Disease Registry (ATSDR) and the National Environmental Health Association (NEHA) launched a partnership to create a free online course with the goal of building capacity within communities to help remediate and redevelop brownfields sites. Brownfields are land reuse sites often contaminated by harmful chemicals or redeveloped without proper environmental oversight. Due to their potentially hazardous status, brownfields sites can lead to harmful exposures in humans while accentuating and often exacerbating socioeconomic disparities within their communities. As a result of this partnership, NEHA and ATSDR launched the Environmental Health and Land Reuse (EHLR) Certificate Program in 2020. The Journal is pleased to feature this column to highlight an example of how the EHLR Certificate Program was used to build understanding and increase knowledge on this important topic within environmental health students. The findings and conclusions in this column are those of the authors and do not necessarily represent the views or official position of NEHA, ATSDR, or the Centers for Disease Control and Prevention. Furthermore, verbal permission was given by the students to use their work in this column.
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OBJECTIVE: To describe maternal haemodynamic differences in gestational hypertension with small-for-gestational-age babies (HDP + SGA), gestational hypertension with appropriate-for-gestational-age babies (HDP-only) and control pregnancies. DESIGN: Prospective cohort study. SETTING: Tertiary Hospital, UK. POPULATION: Women with gestational hypertension and healthy pregnant women. METHODS: Maternal haemodynamic indices were measured using a non-invasive Ultrasound Cardiac Output Monitor (USCOM-1A® ) and corrected for gestational age and maternal characteristics using device-specific reference ranges. MAIN OUTCOME MEASURES: Maternal cardiac output, stroke volume, systemic vascular resistance. RESULTS: We included 114 HDP + SGA, 202 HDP-only and 401 control pregnancies at 26-41 weeks of gestation. There was no significant difference in the mean arterial blood pressure (110 versus 107 mmHg, P = 0.445) between the two HDP groups at presentation. Pregnancies complicated by HDP + SGA had significantly lower median heart rate (76 versus 85 bpm versus 83 bpm), lower cardiac output (0.85 versus 0.98 versus 0.97 MoM) and higher systemic vascular resistance (1.4 versus 1.0 versus 1.2 MoM) compared with control and HDP-only pregnancies, respectively (all P < 0.05). CONCLUSION: Women with HDP + SGA present with more severe haemodynamic dysfunction than HDP-only. Even HDP-only pregnancies exhibit impaired haemodynamic indices compared with normal pregnancies, supporting a role of the maternal cardiovascular system in gestational hypertension irrespective of fetal size. Central haemodynamic changes may play a role in the pathogenesis of pre-eclampsia and should be considered alongside placental aetiology. TWEETABLE ABSTRACT: Hypertensive disorders of pregnancy are associated with worse maternal haemodynamic function when associated with small-for-gestational-age birth.
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Débito Cardíaco/fisiologia , Frequência Cardíaca/fisiologia , Pré-Eclâmpsia/fisiopatologia , Resistência Vascular/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Gravidez , Estudos Prospectivos , Fatores de Risco , Reino UnidoRESUMO
OBJECTIVE: Selective fetal growth restriction (sFGR) occurs in monochorionic twin pregnancies when unequal placental sharing leads to restriction in the growth of just one twin. Management options include laser separation of the fetal circulations, selective reduction or expectant management, but what constitutes the best treatment is not yet known. New trials in this area are urgently needed but, in this rare and complex group, maximizing the relevance and utility of clinical research design and outputs is paramount. A core outcome set ensures standardized outcome collection and reporting in future research. The objective of this study was to develop a core outcome set for studies evaluating treatments for sFGR in monochorionic twins. METHODS: An international steering group of clinicians, researchers and patients with experience of sFGR was established to oversee the process of development of a core outcome set for studies investigating the management of sFGR. Outcomes reported in the literature were identified through a systematic review and informed the design of a three-round Delphi survey. Clinicians, researchers, and patients and family representatives participated in the survey. Outcomes were scored on a Likert scale from 1 (limited importance for making a decision) to 9 (critical for making a decision). Consensus was defined a priori as a Likert score of ≥ 8 in the third round of the Delphi survey. Participants were then invited to take part in an international meeting of stakeholders in which the modified nominal group technique was used to consider the consensus outcomes and agree on a final core outcome set. RESULTS: Ninety-six outcomes were identified from 39 studies in the systematic review. One hundred and three participants from 23 countries completed the first round of the Delphi survey, of whom 88 completed all three rounds. Twenty-nine outcomes met the a priori criteria for consensus and, along with six additional outcomes, were prioritized in a consensus development meeting, using the modified nominal group technique. Twenty-five stakeholders participated in this meeting, including researchers (n = 3), fetal medicine specialists (n = 3), obstetricians (n = 2), neonatologists (n = 3), midwives (n = 4), parents and family members (n = 6), patient group representatives (n = 3), and a sonographer. Eleven core outcomes were agreed upon. These were live birth, gestational age at birth, birth weight, intertwin birth-weight discordance, death of surviving twin after death of cotwin, loss during pregnancy or before final hospital discharge, parental stress, procedure-related adverse maternal outcome, length of neonatal stay in hospital, neurological abnormality on postnatal imaging and childhood disability. CONCLUSIONS: This core outcome set for studies investigating the management of sFGR represents the consensus of a large and diverse group of international collaborators. Use of these outcomes in future trials should help to increase the clinical relevance of research on this condition. Consensus agreement on core outcome definitions and measures is now required. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
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Determinação de Ponto Final , Retardo do Crescimento Fetal/terapia , Procedimentos Cirúrgicos Obstétricos/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde/métodos , Peso ao Nascer , Consenso , Técnica Delphi , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Nascido Vivo , Procedimentos Cirúrgicos Obstétricos/métodos , Gravidez , Gravidez de Gêmeos , Resultado do Tratamento , Gêmeos Monozigóticos/estatística & dados numéricosRESUMO
OBJECTIVE: Pregnancies complicated by pre-eclampsia with a small-for-gestational-age (SGA) neonate have poorer maternal hemodynamic function compared to those with hypertensive disorders of pregnancy (HDP) and an appropriately grown neonate. Arterial stiffness is a recognized prognostic marker of cardiovascular disease in the general population. The aim of this study was to compare maternal arterial stiffness between hypertensive pregnancies with, and those without, a SGA neonate and normotensive control pregnancies. METHODS: This was a prospective cohort study of pregnancies complicated by pre-eclampsia or gestational hypertension and healthy normotensive control pregnancies, presenting to a tertiary referral hospital between January 2012 and May 2018. Maternal arterial stiffness was assessed by aortic pulse-wave velocity (PWV) and aortic augmentation index (AIx), which were recorded using a non-invasive device (Arteriograph®). Maternal and hemodynamic factors were adjusted for using linear regression analysis. Pregnancies with HDP were divided into those that delivered a SGA (birth weight < 10th percentile) neonate (HDP + SGA group) and those that delivered an appropriately grown neonate (HDP-only group). Comparisons between groups were carried out using the Mann-Whitney U-test for continuous variables and the chi-square (or Fisher's exact) test for categorical variables. RESULTS: Included in the analysis were 69 patients with HDP who delivered a SGA neonate, 129 with HDP who delivered a normally grown neonate and 220 healthy controls. Maternal age, weight, height and heart rate were associated significantly with brachial and aortic AIx. Maternal weight, height, mean arterial pressure, heart rate and gestational age were significant predictors of aortic PWV. Adjusted aortic AIx was significantly higher in both the HDP + SGA and HDP-only groups, compared with in controls (12.5% and 10.0% vs 7.6%; both P < 0.01), and was significantly different between the two HDP groups (P = 0.002). Adjusted PWV was significantly higher in the HDP-only group compared with in controls and the HDP + SGA group (7.7 m/s vs 7.1 m/s and 7.1 m/s; both P < 0.001). Conversely, unadjusted PWV was not significantly different between the two HDP groups (P = 0.414). CONCLUSIONS: Pregnancies complicated by HDP with, and those without, a SGA neonate have significantly higher aortic AIx compared with uncomplicated normotensive pregnancies. Aortic AIx was highest in those pregnancies complicated by HDP with a SGA neonate, reflecting a progression in severity of arterial stiffness abnormality with a worsening clinical picture. These findings most likely reflect systemic reduced vascular compliance and increased systemic vascular resistance in pregnancy complicated by HDP. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
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Recém-Nascido Pequeno para a Idade Gestacional , Pré-Eclâmpsia/fisiopatologia , Ultrassonografia Pré-Natal , Artéria Uterina/fisiopatologia , Rigidez Vascular , Adulto , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Prospectivos , Fluxo PulsátilRESUMO
OBJECTIVE: Pregnancies complicated by fetal growth restriction (FGR) have a worse outcome than those with a small-for-gestational-age (SGA) fetus. There is increasing evidence of a maternal cardiovascular role in the pathophysiology of FGR. We aimed to compare maternal hemodynamic indices between pregnancies complicated by FGR and those delivering a SGA neonate, using a non-invasive device. METHODS: This was a prospective study of normotensive pregnancies complicated by FGR (defined as estimated fetal weight (EFW) < 3rd centile or Doppler evidence of impaired placental-fetal blood flow), those with a SGA fetus (defined as EFW < 10th centile) and control pregnancies with an appropriately grown fetus. Assessment of maternal hemodynamics (heart rate (HR), cardiac output (CO), mean arterial pressure (MAP), systemic vascular resistance (SVR) and stroke volume) was performed using a non-invasive device (USCOM-1A®). Uterine artery (UtA) pulsatility index (PI) was measured using transabdominal ultrasound. Hemodynamic variables that are affected by gestational age and maternal characteristics were corrected for using device-specific reference ranges. Comparison between groups was performed using the chi-square test or the Mann-Whitney U-test, as appropriate. RESULTS: A total of 102 FGR, 64 SGA and 401 control pregnancies, with a median gestational age of 36 weeks, were included in the analysis. Women with a pregnancy complicated by FGR and those with a SGA fetus were shorter and weighed less than did controls. Compared with controls, the FGR group had significantly lower median maternal HR (80 beats per min (bpm) vs 85 bpm; P = 0.001) and CO multiples of the median (MoM; 0.91 vs 0.98; P = 0.003), and higher median maternal MAP (90 mmHg vs 87 mmHg; P = 0.040), SVR MoM (1.2 vs 1.0; P < 0.001) and UtA-PI MoM (1.1 vs 0.96; P < 0.001), but there was no significant difference in stroke volume MoM (1.0 vs 0.98; P = 0.647). Compared with the SGA group, the FGR group had a significantly lower median HR (80 bpm vs 87 bpm; P = 0.022), and higher median maternal MAP (90 mmHg vs 85 mmHg; P = 0.025), SVR MoM (1.2 vs 1.0; P = 0.002) and UtA-PI MoM (1.1 vs 0.98; P = 0.005), but there was no significant difference in CO MoM (0.91 vs 0.96; P = 0.092) or stroke volume MoM (1.0 vs 1.0; P = 0.806). There were no significant differences in adjusted maternal hemodynamic indices between the SGA group and controls. CONCLUSION: Pregnancies complicated by FGR presented with impaired maternal hemodynamic function, as evidenced by lower HR and CO, as well as higher MAP, SVR and UtA resistance. Pregnancies delivering a SGA neonate, without evidence of FGR, had normal maternal hemodynamic function. Maternal hemodynamic indices may therefore be of value in distinguishing FGR from SGA pregnancies. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
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Retardo do Crescimento Fetal/diagnóstico , Hemodinâmica , Complicações Cardiovasculares na Gravidez/fisiopatologia , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Adulto , Pressão Arterial , Biomarcadores/análise , Débito Cardíaco , Feminino , Retardo do Crescimento Fetal/etiologia , Peso Fetal , Feto/irrigação sanguínea , Feto/diagnóstico por imagem , Idade Gestacional , Frequência Cardíaca , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Circulação Placentária , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico por imagem , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Fluxo Pulsátil , Volume Sistólico , Artéria Uterina/diagnóstico por imagem , Artéria Uterina/fisiopatologia , Resistência VascularRESUMO
Recent research on interfacial instabilities of smectic films has shown unexpected morphologies that are not fully explained by classical local equilibrium thermodynamics. Annealing focal conic domains can lead to conical pyramids, changing the sign of the Gaussian curvature and exposing smectic layers at the interface. In order to explore the role of the Gaussian curvature on the stability and evolution of the film-vapor interface, we introduce a phase-field model of a smectic-isotropic system as a first step in the study. Through asymptotic analysis of the model, we generalize the classical condition of local equilibrium, the Gibbs-Thomson equation, to include contributions from surface bending and torsion and a dependence on the layer orientation at the interface. A full numerical solution of the phase-field model is then used to study the evolution of focal conic structures in smectic domains in contact with the isotropic phase via local evaporation and condensation of smectic layers. As in experiments, numerical solutions show that pyramidal structures emerge near the center of the focal conic owing to evaporation of adjacent smectic planes and to their orientation relative to the interface. Near the center of the focal conic domain, a correct description of the motion of the interface requires the additional curvature terms obtained in the asymptotic analysis, thus clarifying the limitations in modeling motion of hyperbolic surfaces solely driven by mean curvature.
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CONTEXT: In Pennsylvania, reporting of viral hepatitis B (HBV) and viral hepatitis C (HCV) infections to CDC has been mandated since 2002. Underreporting of HBV and HCV infections has long been identified as a problem. Few reports have described the accuracy of state surveillance case registries for recording clinically-confirmed cases of HBV and HCV infections, or the characteristics of populations associated with lower rates of reporting. OBJECTIVE: The primary objective of the current study is to estimate the proportion of HBV and HCV infections that went unreported to the Pennsylvania Department of Health (PDoH), among patients in the Geisinger Health System of Pennsylvania. As a secondary objective, we study the association between underreporting of HBV and HCV infections to PDoH, and the select patient characteristics of interest: sex, age group, race/ethnicity, rural status, and year of initial diagnosis. DESIGN: Per medical record review, the study population was limited to Geisinger Health System patients, residing in Pennsylvania, who were diagnosed with a chronic HBV and/or HCV infection, between 2001 and 2015. Geisinger Health System patient medical records were matched to surveillance records of confirmed cases reported to the Pennsylvania Department of Health (PDoH). To quantify the extent that underreporting occurred among the Geisinger Health System study participants, we calculated the proportion of study participants that were not reported to PDoH as confirmed cases of HBV or HCV infections. An analysis of adjusted prevalence ratio estimates was conducted to study the association between underreporting of HBV and HCV infections to PDoH, and the select patient characteristics of interest. RESULTS: Geisinger Health System patients living with HBV were reported to PDoH 88.4% (152 of 172) of the time; patients living with HCV were reported to PDoH 94.6% (2,257 of 2,386) of the time; and patients who were co-infected with both viruses were reported to PDoH 72.0% (18 of 25) of the time. Patients living with HCV had an increased likelihood of being reported if they were: less than or equal to age 30 vs ages 65+ {PR = 1.2, [95%CI, (1.1, 1.3)]}, and if they received their initial diagnosis of HCV during the 2010-2015 time period vs the 1990-1999 time period {PR = 1.08, [95%CI, (1.05, 1.12)]}. CONCLUSION: The findings in this study are promising, and suggests that PDoH has largely been successful with tracking and monitoring viral hepatitis B and C infections, among persons that were tested for HBV and/or HCV. Additional efforts should be placed on decreasing underreporting rates of HCV infections among seniors (ages 65 and over), and persons who are co-infected with HBV and HCV.
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Monitoramento Epidemiológico , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Sistema de Registros , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Hepatite B/diagnóstico , Hepatite C/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pennsylvania/epidemiologiaRESUMO
OBJECTIVE: To develop, using a Delphi procedure and a nominal group technique, a core outcome set (COS) for studies evaluating treatments for twin-twin transfusion syndrome (TTTS), which should assist in standardizing outcome selection, collection and reporting in future research studies. METHODS: An international steering group comprising healthcare professionals, researchers and patients with experience of TTTS guided the development of this COS. Potential core outcomes, identified through a comprehensive literature review and supplemented by outcomes suggested by the steering group, were entered into a three-round Delphi survey. Healthcare professionals, researchers, and patients or relatives of patients who had experienced TTTS were invited to participate. Consensus was defined a priori using the 15%/70% definition of the Core Outcome Measures in Effectiveness Trials (COMET) initiative. The modified nominal group technique was used to evaluate the consensus outcomes in a face-to-face consultation meeting and identify the final COS. RESULTS: One hundred and three participants, from 29 countries, participated in the three-round Delphi survey. Of those, 88 completed all three rounds. Twenty-two consensus outcomes were identified through the Delphi procedure and entered into the modified nominal group technique. The consensus meeting was attended by 11 healthcare professionals, two researchers and three patients; 12 core outcomes were prioritized for inclusion in the COS. Fetal core outcomes included live birth, pregnancy loss (including miscarriage, stillbirth, termination of pregnancy and neonatal mortality), subsequent death of a cotwin following single-twin demise at the time of treatment, recurrence of TTTS, twin anemia-polycythemia sequence and amniotic band syndrome. Neonatal core outcomes included gestational age at delivery, birth weight, brain injury syndromes and ischemic limb injury. Maternal core outcomes included maternal mortality and admission to Level-2 or -3 care setting. One aspirational outcome, neurodevelopment at 18-24 months of age, was also prioritized. CONCLUSIONS: Implementing the COS for TTTS within future research studies could make a substantial contribution to advancing the usefulness of research in TTTS. Standardized definitions and measurement instruments are now required for individual core outcomes. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Determinação de Ponto Final/métodos , Transfusão Feto-Fetal/terapia , Avaliação de Resultados em Cuidados de Saúde/tendências , Resultado da Gravidez/epidemiologia , Adolescente , Adulto , Consenso , Técnica Delphi , Feminino , Transfusão Feto-Fetal/diagnóstico , Idade Gestacional , Ocupações em Saúde , Humanos , Masculino , Mortalidade Materna , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Projetos de Pesquisa , Participação dos Interessados , Inquéritos e Questionários , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVES: To construct reference ranges for stroke volume, cardiac output and systemic vascular resistance (SVR) in normal pregnancy for the NICOM® device, and to explore associations between maternal characteristics and these hemodynamic variables. METHODS: This was a prospective cohort study of healthy singleton pregnancies between 10 and 40 weeks' gestation attending a tertiary referral hospital between September 2012 and May 2018. Measurements of stroke volume, cardiac output and SVR were obtained throughout pregnancy using NICOM, a non-invasive device based on bioreactance technology. NICOM device-specific reference ranges were created with respect to gestational age and maternal characteristics. Once the distribution of the data had been determined with respect to the gestational age, patient characteristics were added to the model to test whether they provided a significant improvement in prediction of the median value. The effect was assessed of maternal weight, height, smoking status, conception using assisted reproductive technology, nulliparity and ethnicity. RESULTS: We included 411 women in this study. The relationships between cardiac variables and gestational age observed in the NICOM-specific reference ranges are consistent with previous findings, with increasing cardiac output values until around 35 weeks and a decrease thereafter until term, and decreasing SVR until around 36 weeks, followed by an increase towards 40 weeks. Stroke volume showed a small linear increase across gestation with lower variability in observations close to term. Maternal weight, height and age were associated with cardiac output (all P < 0.05) and SVR (all P < 0.01), whilst maternal weight and height were associated with stroke volume (both P < 0.001). Ethnicity was significantly associated with stroke volume (P = 0.001) but not with cardiac output or SVR. CONCLUSIONS: This study presents device-specific reference ranges for stroke volume, cardiac output and SVR for the NICOM device in healthy pregnancy and describes the maternal characteristics that are associated with the values of these hemodynamic measurements. Studies using NICOM in pregnancy can use these ranges in order to evaluate observations relative to those expected in uncomplicated pregnancy conditional on maternal characteristics. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Débito Cardíaco/fisiologia , Monitorização Fisiológica/instrumentação , Gravidez/fisiologia , Volume Sistólico/fisiologia , Resistência Vascular/fisiologia , Adulto , Estatura , Peso Corporal , Feminino , Idade Gestacional , Humanos , Idade Materna , Estudos Prospectivos , Valores de ReferênciaRESUMO
OBJECTIVE: Traditional blood-pressure monitoring in hypertensive pregnant women requires frequent visits to the maternity outpatient services. Home blood-pressure monitoring (HBPM) could offer a cost-saving alternative that is acceptable to patients. The aim of this study was to undertake a health economic analysis of HBPM compared with traditional monitoring in hypertensive pregnant women. METHODS: This was a cost-minimization study of hypertensive pregnant women who had HBPM with or without the adjunct of a smartphone application (App), via a specially designed pathway, and a control group managed according to the local protocol of regular hospital visits for blood-pressure monitoring. Outcome measures were the number of outpatient visits, inpatient bed stays and investigations performed. Maternal, fetal and neonatal adverse outcomes were also recorded. Health economic analysis was performed using direct cost comparison of the study dataset and process scenario modeling. RESULTS: The HBPM group included 108 women, of whom 29 recorded their results on the smartphone App and 79 in their notes. The control group comprised 58 patients. There were significantly more women with chronic hypertension in the HBPM group than in the control group (49.1% vs 25.9%, P = 0.004). The HBPM group had significantly longer duration of monitoring (9 weeks vs 5 weeks, P = 0.004) and started monitoring at an earlier gestational age (30.0 weeks vs 33.6 weeks, P = 0.001) compared with the control group. Despite these differences, the mean saving per week for each patient using HBPM compared with traditional monitoring was £200.69, while for each HBPM patient using the smartphone App, the weekly saving was £286.53 compared with the control group. The process modeling method predicted weekly savings of between £98.32 and £245.80 per patient using HBPM compared with traditional monitoring. CONCLUSION: HBPM in hypertensive pregnancy appears to be cost saving compared with traditional monitoring, without compromising maternal, fetal or neonatal safety. Larger studies are required to confirm these findings. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Monitorização Ambulatorial da Pressão Arterial/economia , Hipertensão Induzida pela Gravidez/economia , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Análise Custo-Benefício , Feminino , Humanos , Hipertensão Induzida pela Gravidez/diagnóstico , Aplicativos Móveis , Gravidez , Cuidado Pré-Natal/economia , SmartphoneRESUMO
OBJECTIVE: Maternal hemodynamics change significantly during Cesarean section complicated by massive hemorrhage or severe hypertensive disease. Cardiac output (CO) monitoring aids early, goal-directed hemodynamic therapy. The aim of this study was to record hemodynamic changes observed during Cesarean section in pregnancies at high risk of hemodynamic instability, using invasive (LiDCOrapid™) and non-invasive (NICOM®) devices, and to assess agreement between the two devices in measuring CO. METHODS: Simultaneous intraoperative hemodynamic measurements were taken using the LiDCOrapid and NICOM devices, following standardized techniques, in women at high risk of hemodynamic instability undergoing Cesarean section. Agreement in CO measurements between the two devices was assessed using Bland-Altman plots and the agreement:tolerability index (ATI). Agreement analyses were performed for repeated measures in subjects, using centiles. RESULTS: From 10 women, 307 paired measurements were analyzed. Mean bias (defined as the mean difference in CO measurements between the LiDCOrapid and NICOM devices) was 3.05 (95% CI, 1.89 to 4.21) L/min. Limits of agreement ranged from -1.58 (95% CI, -4.47 to -0.14) to 7.68 (95% CI, 6.24 to 10.56) L/min. The resulting agreement interval was 9.26 L/min which returned an ATI of 2.3. CONCLUSIONS: There are large mean differences between CO measurements obtained during Cesarean section using the LiDCOrapid and NICOM hemodynamic monitors in pregnant women at high risk of hemodynamic instability, indicating that they should not be considered interchangeable clinically. There is an unacceptably low level of agreement (ATI > 2) in CO measurements between the devices, conferring a high risk of clinical misclassification during massive hemorrhage. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Assuntos
Débito Cardíaco/fisiologia , Cesárea/estatística & dados numéricos , Gravidez de Alto Risco/fisiologia , Adulto , Feminino , Idade Gestacional , Hemodinâmica/fisiologia , Hemorragia/complicações , Humanos , Monitorização Intraoperatória/instrumentação , Monitorização Fisiológica , Gravidez , Estudos ProspectivosRESUMO
OBJECTIVE: Pregnancies affected by a hypertensive disorder (HDP) have increased uterine artery pulsatility index (UtA-PI) compared with that in healthy pregnancies. Women with HDP are also known to have lower cardiac output and increased systemic vascular resistance. The aim of this study was to investigate the relationship between central and uterine hemodynamics in HDP and uncomplicated pregnancy. METHODS: This was a prospective study of HDP and normotensive control singleton pregnancies presenting at a tertiary referral hospital between January 2012 and December 2017. Paired measurements of maternal hemodynamics, using a non-invasive device (USCOM-1A®), and UtA-PI were performed in the third trimester. HDP pregnancies were divided into preterm (onset < 37 weeks' gestation) and term (onset ≥ 37 weeks). Spearman's rank coefficient was used to assess the correlation between the central and uteroplacental hemodynamics. Regression analysis was performed to assess the association of UtA-PI with independent variables. RESULTS: We included 231 women with HDP (152 with preterm and 79 with term HDP) and 378 controls with normotensive pregnancy. Compared with controls, women with preterm HDP had significantly lower cardiac output (median (interquartile range (IQR)), 6.0 (5.1-7.2) vs 6.6 (5.8-7.5) L/min; P < 0.001) and significantly higher systemic vascular resistance (median (IQR), 1394 (1189-1670) vs 1063 (915-1222) dynes × s/cm5 ; P < 0.001) and UtA-PI (median (IQR), 1.0 (0.75-1.4) vs 0.67 (0.58-0.83); P < 0.001). Conversely, in women with term HDP, there were no significant differences in heart rate, cardiac output or UtA-PI compared with controls (all P > 0.05), while systemic vascular resistance was significantly higher (median (IQR), 1315 (1099-1527) vs 1063 (915-1222) dynes × s/cm5 ; P < 0.001). On multiple regression analysis, heart rate, mean arterial pressure and stroke volume were associated significantly with mean UtA-PI (all P < 0.001). CONCLUSIONS: Differences observed between HDP and normotensive pregnancies in third-trimester UtA resistance are mirrored in the central maternal hemodynamic parameters. Late pregnancy differences in the uteroplacental circulation in preterm and term HDP are an index of maternal cardiovascular function rather than being related to inadequate spiral artery remodeling and impaired placentation. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.