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1.
Clin Obstet Gynecol ; 66(2): 415-424, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37204165

RESUMO

Obstetric hemorrhage is one of the most commonly encountered obstetrical complications. Decreases in maternal mortality and severe maternal morbidity have continued to be achieved despite the increasing incidence of obstetric hemorrhage over time through the diligent efforts of quality improvement initiatives. Approaches currently advocated to optimize the management of obstetrical hemorrhage are presented and discussed in this chapter focusing on readiness, recognition and prevention, clinical response, patient support, and tracking and monitoring outcome and performance measures over time. Readers are encouraged to access publicly available programs from state-based perinatal quality collaboratives and national programs designed to support and structure such efforts.


Assuntos
Obstetrícia , Hemorragia Pós-Parto , Gravidez , Feminino , Humanos , Hemorragia , Melhoria de Qualidade , Atenção à Saúde , Mortalidade Materna , Hemorragia Pós-Parto/prevenção & controle
2.
J Chem Phys ; 156(11): 114115, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35317589

RESUMO

Hydrogen tunneling plays a critical role in many biologically and chemically important processes. The nuclear-electronic orbital multistate density functional theory (NEO-MSDFT) method was developed to describe hydrogen transfer systems. In this approach, the transferring proton is treated quantum mechanically on the same level as the electrons within multicomponent DFT, and a nonorthogonal configuration interaction scheme is used to produce delocalized vibronic states from localized vibronic states. The NEO-MSDFT method has been shown to provide accurate hydrogen tunneling splittings for fixed molecular systems. Herein, the NEO-MSDFT analytical gradients for both ground and excited vibronic states are derived and implemented. The analytical gradients and semi-numerical Hessians are used to optimize and characterize equilibrium and transition state geometries and to generate minimum energy paths (MEPs), for proton transfer in the deprotonated acetylene dimer and malonaldehyde. The barriers along the resulting MEPs are lower when the transferring proton is quantized because the NEO-MSDFT method inherently includes the zero-point energy of the transferring proton. Analysis of the proton densities along the MEPs illustrates that the proton density can exhibit symmetric or asymmetric bilobal character associated with symmetric or slightly asymmetric double-well potential energy surfaces and hydrogen tunneling. Analysis of the contributions to the intrinsic reaction coordinate reveals that changes in the C-O bond lengths drive proton transfer in malonaldehyde. This work provides the foundation for future reaction path studies and direct nonadiabatic dynamics simulations of a wide range of hydrogen transfer reactions.

3.
J Chem Phys ; 154(5): 054108, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33557565

RESUMO

The nuclear-electronic orbital (NEO) method is a multicomponent quantum chemistry theory that describes electronic and nuclear quantum effects simultaneously while avoiding the Born-Oppenheimer approximation for certain nuclei. Typically specified hydrogen nuclei are treated quantum mechanically at the same level as the electrons, and the NEO potential energy surface depends on the classical nuclear coordinates. This approach includes nuclear quantum effects such as zero-point energy and nuclear delocalization directly into the potential energy surface. An extended NEO potential energy surface depending on the expectation values of the quantum nuclei incorporates coupling between the quantum and classical nuclei. Herein, theoretical methodology is developed to optimize and characterize stationary points on the standard or extended NEO potential energy surface, to generate the NEO minimum energy path from a transition state down to the corresponding reactant and product, and to compute thermochemical properties. For this purpose, the analytic coordinate Hessian is developed and implemented at the NEO Hartree-Fock level of theory. These NEO Hessians are used to study the SN2 reaction of ClCH3Cl- and the hydride transfer of C4H9 +. For each system, analysis of the single imaginary mode at the transition state and the intrinsic reaction coordinate along the minimum energy path identifies the dominant nuclear motions driving the chemical reaction. Visualization of the electronic and protonic orbitals along the minimum energy path illustrates the coupled electronic and protonic motions beyond the Born-Oppenheimer approximation. This work provides the foundation for applying the NEO approach at various correlated levels of theory to a wide range of chemical reactions.

4.
Am J Perinatol ; 38(2): 111-114, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32772358

RESUMO

OBJECTIVE: Isolated fetal ventriculomegaly is often an incidental finding on antenatal ultrasound. It is benign in up to 90% of cases, although it can be associated with genetic, structural, and neurocognitive disorders. The literature suggests that over 40% of isolated mild ventriculomegaly will resolve in utero, but it is unclear if resolution decreases the associated risks.The aim of this study is to compare the fetal and neonatal genetic outcomes of ventriculomegaly that persists or resolves on subsequent ultrasound. STUDY DESIGN: This is a retrospective cohort study of women diagnosed with isolated ventriculomegaly via fetal ultrasound at a tertiary referral center between 2011 and 2019. Patients were excluded if other structural anomalies were identified on ultrasound. RESULTS: A total of 49 patients were included in the study, 19 in the resolved ventriculomegaly group and 30 in the persistent ventriculomegaly group. Women in the resolved ventriculomegaly group were more likely to be diagnosed earlier (24 vs. 28 weeks, p = 0.007). Additionally, they were more likely to have mild ventriculomegaly (63 vs. 84%, p = 0.15), and less likely to have structural neurological abnormalities diagnosed on postnatal imaging (5 vs. 17%, p = 0.384), although these were not statistically significant. Aneuploidy risk for resolved compared with persistent ventriculomegaly was similar (5 vs. 7%, p = 0.999). CONCLUSION: This study suggests that resolution of isolated ventriculomegaly in utero may not eliminate the risk of genetic or chromosomal abnormalities in this population and may warrant inclusion as part of the counselling of these at-risk patients. Larger prospective studies are needed to confirm these findings. KEY POINTS: · Ventriculomegaly is known to be associated with genetic and chromosomal abnormalities.. · Resolution of the ventriculomegaly in utero may not eliminate those risks.. · Patients with resolved ventriculomegaly should be offered aneuploidy screening or testing..


Assuntos
Aberrações Cromossômicas/embriologia , Hidrocefalia/enzimologia , Adulto , Aneuploidia , Feminino , Desenvolvimento Fetal , Humanos , Hidrocefalia/complicações , Hidrocefalia/diagnóstico por imagem , Ohio , Gravidez , Centros de Atenção Terciária , Ultrassonografia Pré-Natal , Adulto Jovem
5.
Am J Perinatol ; 38(10): 983-992, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33934326

RESUMO

OBJECTIVE: Sustained blood pressures ≥160/110 during pregnancy and the postpartum period require timely antihypertensive therapy. Hospital-level experiences outlining the efforts to improve timely delivery of care within 60 minutes have not been described. The objective of this analysis was to assess changes in care practices of an inpatient obstetrical health care team following the implementation of a quality improvement initiative for severe perinatal hypertension during pregnancy and the postpartum period. STUDY DESIGN: In January 2016, NorthShore University HealthSystem Evanston Hospital launched a quality improvement initiative focusing on perinatal hypertension, as part of a larger, statewide quality initiative via the Illinois Perinatal Quality Collaborative. We performed a retrospective cohort study of all pregnant and postpartum patients with sustained severely elevated blood pressure (two severely elevated blood pressures ≤15 minutes apart) with baseline data from 2015 and data collected during the project from 2016 through 2017. Changes in clinical practice and outcomes were compared before and after the start of the project. Statistical process control charts were used to demonstrate process-behavior changes over time. RESULTS: Comparing the baseline to the last quarter of 2017, there was a significant increase in the administration of medication within 60 minutes for severe perinatal hypertension (p <0.001). Implementation of a protocol for event-specific debriefing for each severe perinatal hypertension episode was associated with increased odds of the care team administering medication within 60 minutes of the diagnosis of severe perinatal hypertension (adjusted odds ratio 3.20, 95% confidence interval 1.73-5.91, p < 0.01). CONCLUSION: Implementation of a quality improvement initiative for perinatal hypertension associated with pregnancy and postpartum improved the delivery of appropriate and timely therapy for severely elevated blood pressures and demonstrated the impact of interdisciplinary communication in the process. KEY POINTS: · Process of hospital-level implementation of a state quality improvement initiative.. · Evidence of improvement in care delivery for severe perinatal hypertension (HTN).. · Episode related debriefing by the clinical team improved perinatal HTN care..


Assuntos
Anti-Hipertensivos/administração & dosagem , Hipertensão Induzida pela Gravidez/tratamento farmacológico , Padrões de Prática Médica , Melhoria de Qualidade , Tempo para o Tratamento , Adulto , Feminino , Humanos , Illinois , Ciência da Implementação , Modelos Logísticos , Cuidado Pós-Natal/métodos , Guias de Prática Clínica como Assunto , Gravidez , Estudos Retrospectivos
6.
Crit Care ; 24(1): 582, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993736

RESUMO

After the World Health Organization declared COVID-19 to be a pandemic, the elaboration of comprehensive and preventive public policies became important in order to stop the spread of the disease. However, insufficient or ineffective measures may have placed health professionals and services in the position of having to allocate mechanical ventilators. This study aimed to identify instruments, analyze their structures, and present the main criteria used in the screening protocols, in order to help the development of guidelines and policies for the allocation of mechanical ventilators in the COVID-19 pandemic. The instruments have a low level of scientific evidence, and, in general, are structured by various clinical, non-clinical, and tiebreaker criteria that contain ethical aspects. Few instruments included public participation in their construction or validation. We believe that the elaboration of these guidelines cannot be restricted to specialists as this question involves ethical considerations which make the participation of the population necessary. Finally, we propose seventeen elements that can support the construction of screening protocols in the COVID-19 pandemic.


Assuntos
Infecções por Coronavirus/terapia , Pneumonia Viral/terapia , Alocação de Recursos , Ventiladores Mecânicos , Betacoronavirus , COVID-19 , Tomada de Decisões , Humanos , Pandemias , Saúde Pública , SARS-CoV-2 , Triagem/métodos
7.
J Chem Phys ; 153(22): 224111, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317298

RESUMO

The recently developed real-time nuclear-electronic orbital (RT-NEO) approach provides an elegant framework for treating electrons and selected nuclei, typically protons, quantum mechanically in nonequilibrium dynamical processes. However, the RT-NEO approach neglects the motion of the other nuclei, preventing a complete description of the coupled nuclear-electronic dynamics and spectroscopy. In this work, the dynamical interactions between the other nuclei and the electron-proton subsystem are described with the mixed quantum-classical Ehrenfest dynamics method. The NEO-Ehrenfest approach propagates the electrons and quantum protons in a time-dependent variational framework, while the remaining nuclei move classically on the corresponding average electron-proton vibronic surface. This approach includes the non-Born-Oppenheimer effects between the electrons and the quantum protons with RT-NEO and between the classical nuclei and the electron-proton subsystem with Ehrenfest dynamics. Spectral features for vibrational modes involving both quantum and classical nuclei are resolved from the time-dependent dipole moments. This work shows that the NEO-Ehrenfest method is a powerful tool to study dynamical processes with coupled electronic and nuclear degrees of freedom.

8.
Molecules ; 25(7)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230750

RESUMO

To advance the technology of polymer electrolyte membrane fuel cells, material development is at the forefront of research. This is especially true for membrane electrode assembly, where the structuring of its various layers has proven to be directly linked to performance increase. In this study, we investigate the influence of the various ingredients in the cathode catalyst layer, such as ionomer content, catalyst loading and catalyst type, on the oxygen and ion transport using a full parametric analysis. Using two types of catalysts, 40 wt.% Pt/C and 60 wt.% Pt/C with high surface area carbon, the ionomer/carbon content was varied between 0.29-1.67, while varying the Pt loading in the range of 0.05-0.8 mg cm-2. The optimum ionomer content was found to be dependent on the operating point and condition, as well as catalyst loading and type. The data set provided in this work gives a starting point to further understanding of structured catalyst layers.


Assuntos
Carbono/química , Eletroquímica/métodos , Membranas Artificiais , Oxigênio/química , Platina/química , Polímeros/química , Catálise , Eletrodos , Eletrólitos/química , Íons/química , Microscopia Eletrônica de Varredura
9.
J Am Chem Soc ; 140(34): 10890-10899, 2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30060652

RESUMO

A soluble, bis-ketiminate-ligated Co complex [Co(N2O2)] was recently shown to catalyze selective reduction of O2 to H2O2 with an overpotential as low as 90 mV. Here we report experimental and computational mechanistic studies of the Co(N2O2)-catalyzed O2 reduction reaction (ORR) with decamethylferrocene (Fc*) as the reductant in the presence of AcOH in MeOH. Analysis of the Co/O2 binding stoichiometry and kinetic studies support an O2 reduction pathway involving a mononuclear cobalt species. The catalytic rate exhibits a first-order kinetic dependence on [Co(N2O2)] and [AcOH], but no dependence on [Fc*] or [O2]. Differential pulse voltammetry and computational studies support CoIII-hydroperoxide as the catalyst resting state and protonation of this species as the rate-limiting step of the catalytic reaction. These results contrast previous mechanisms proposed for other Co-catalyzed ORR systems, which commonly feature rate-limiting protonation of a CoIII-superoxide adduct earlier in the catalytic cycle. Computational studies show that protonation is strongly favored at the proximal oxygen of the CoIII(OOH) species, accounting for the high selectivity for formation of hydrogen peroxide. Further analysis shows that a weak dependence of the ORR rate on the p Ka values of the protonated CoIII(OOH) species across a series of Co(N2O2) catalysts provides a rationale for the unusually low overpotential observed for O2 reduction to H2O2.

10.
J Chem Phys ; 149(4): 044110, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-30068159

RESUMO

Multicomponent density functional theory (DFT) allows the consistent quantum mechanical treatment of both electrons and nuclei. Recently the epc17 electron-proton correlation functional was derived using a multicomponent extension of the Colle-Salvetti formalism and was implemented within the nuclear-electronic orbital (NEO) framework for treating electrons and specified protons quantum mechanically. Herein another electron-proton correlation functional, denoted epc18, is derived using a different form for the functional parameter interpreted as representing the correlation length for electron-proton interactions. The epc18 functional is shown to perform similarly to the epc17 functional for predicting three-dimensional proton densities and proton affinities. Both functionals are shown to be transferable for use with a series of diverse electronic exchange-correlation functionals, indicating that any reasonable electronic exchange-correlation functional may be used in tandem with the epc17 and epc18 electron-proton correlation functionals. Understanding the impact of different forms of the electron-proton correlation functional, as well as the interplay between electron-proton and electron-electron correlation, is critical for the general applicability of NEO-DFT.

11.
Zentralbl Chir ; 143(4): 400-407, 2018 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-30016811

RESUMO

BACKGROUND: In recent years, there has been a significant change in the treatment recommendations for acute diverticulitis. In order to provide the right treatment to the individual patient, it is therefore important to classify the stage of the disease accurately, after taking various aspects into consideration. METHODS: Patients treated for acute diverticulitis in Würzburg University Hospital during 2010 to 2014 were included. Inclusion criteria were the presence of a computer tomography for disease classification. RESULTS: More than half of the patients examined (n = 135, 52.9%) had acute uncomplicated diverticulitis on admission; 112 (43.2%) had a covered perforation (small paracolic abscess n = 63, 24,3%; large abscess n = 49, 18,9%) and 12 (4.6%) a free perforation. In a total of 150 (57.9%) patients, this was the first episode of diverticulitis, with a covered (66.1%) or a free perforation (75.0%) occurring at a higher than average rate as the first manifestation. Nearly two-thirds (66.4%, n = 168) of patients underwent sigmoid resection during follow-up. DISCUSSION AND CONCLUSION: Despite current trends towards more conservative therapy of acute diverticulitis, sigmoid resection remains a corner stone of successful therapy throughout all types of acute diverticulitis. The indication of sigmoid resection nowadays requires profound knowledge of the individual prognosis for recurrent diverticulitis and quality of life.


Assuntos
Diverticulite , Doença Aguda , Estudos de Coortes , Diverticulite/classificação , Diverticulite/diagnóstico , Diverticulite/epidemiologia , Diverticulite/terapia , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
12.
Am J Obstet Gynecol ; 216(3): 300.e1-300.e5, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27823918

RESUMO

BACKGROUND: Intrauterine balloon tamponade is an effective treatment for postpartum hemorrhage when first-line treatments fail. The optimal duration of intrauterine balloon tamponade for management of postpartum hemorrhage is unclear. OBJECTIVE: The objective of the study was to determine whether intrauterine balloon tamponade removal >12 hours of duration is associated with postpartum hemorrhage-related clinical outcomes. STUDY DESIGN: This was a retrospective cohort study of women with postpartum hemorrhage from 2007 through 2014 who underwent intrauterine balloon tamponade. We excluded failures of intrauterine balloon tamponade (intrauterine balloon expulsion with duration <2 hours or if hysterectomy was required prior to planned intrauterine balloon removal). Patients who underwent intrauterine balloon tamponade for 2-12 hours were compared with those who underwent intrauterine balloon tamponade for >12 hours. Examined postpartum hemorrhage-related clinical outcomes included estimated blood loss after intrauterine balloon tamponade placement, blood product transfusion, use of adjuvant measures to control postpartum hemorrhage after intrauterine balloon tamponade (either uterine artery embolization or hysterectomy), and maternal intensive care unit admission. Secondary outcomes examined included postpartum fever and hospital length of stay. Multivariable logistic regression models were used to control for confounding variables. RESULTS: Of 274 eligible women, 206 (75%) underwent intrauterine balloon tamponade for >12 hours and 68 (25%) underwent intrauterine balloon tamponade for 2-12 hours. The median estimated blood loss after intrauterine balloon tamponade placement (190 vs 143 mL, P = .116) as well as the frequencies of blood product transfusion (62.1% vs 51.5%, P = .120), transfusion of ≥4 U of packed red blood cells (17.0% vs 14.7%, P = .659), uterine artery embolization (15.1% vs 16.2%, P = .823), hysterectomy (0.0% vs 1.5%, P = .248), and intensive care unit admission (8.7% vs 7.4%, P = .721), was not statistically different between the groups, and this lack of association persisted in multivariable regressions. Intrauterine balloon tamponade duration >12 hours was associated with a higher frequency of postpartum fever (27% vs 15%, P = .047) and a longer mean hospital length of stay (3.7 vs 3.1 days, P = .002). After adjusting for variables that differed statistically between groups, the difference in length of stay associated with intrauterine balloon tamponade duration was no longer present, but the association between intrauterine balloon tamponade duration >12 hours and postpartum fever persisted (odds ratio, 2.33, 95% confidence interval, 1.07-5.11). Including chorioamnionitis as an independent variable in a post hoc multivariable analysis diminished the association between intrauterine balloon tamponade >12 hours and postpartum fever (adjusted odds ratio, 2.04, 95% confidence interval, 0.92-4.53). CONCLUSION: There are no significant differences in postpartum hemorrhage-related outcomes associated with intrauterine balloon tamponade duration >12 hours compared with removal 2-12 hours. If ongoing hemorrhage has abated, it is reasonable to consider the removal of an intrauterine balloon by 12 hours after its initial placement.


Assuntos
Oclusão com Balão , Hemorragia Pós-Parto/terapia , Embolização da Artéria Uterina/métodos , Adulto , Estudos de Coortes , Feminino , Humanos , Histerectomia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
13.
Cereb Cortex ; 26(7): 3260-72, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26980613

RESUMO

Plasticity-related gene-1 (PRG-1) is a brain-specific protein that modulates glutamatergic synaptic transmission. Here we investigated the functional role of PRG-1 in adolescent and adult mouse barrel cortex both in vitro and in vivo. Compared with wild-type (WT) animals, PRG-1-deficient (KO) mice showed specific behavioral deficits in tests assessing sensorimotor integration and whisker-based sensory discrimination as shown in the beam balance/walking test and sandpaper tactile discrimination test, respectively. At P25-31, spontaneous network activity in the barrel cortex in vivo was higher in KO mice compared with WT littermates, but not at P16-19. At P16-19, sensory evoked cortical responses in vivo elicited by single whisker stimulation were comparable in KO and WT mice. In contrast, at P25-31 evoked responses were smaller in amplitude and longer in duration in WT animals, whereas KO mice revealed no such developmental changes. In thalamocortical slices from KO mice, spontaneous activity was increased already at P16-19, and glutamatergic thalamocortical inputs to Layer 4 spiny stellate neurons were potentiated. We conclude that genetic ablation of PRG-1 modulates already at P16-19 spontaneous and evoked excitability of the barrel cortex, including enhancement of thalamocortical glutamatergic inputs to Layer 4, which distorts sensory processing in adulthood.


Assuntos
Proteínas de Ligação a Calmodulina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Córtex Somatossensorial/metabolismo , Transmissão Sináptica/fisiologia , Tálamo/metabolismo , Vibrissas/fisiologia , Animais , Proteínas de Ligação a Calmodulina/genética , Feminino , Ácido Glutâmico/metabolismo , Masculino , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Vias Neurais/crescimento & desenvolvimento , Vias Neurais/metabolismo , Plasticidade Neuronal/fisiologia , Técnicas de Patch-Clamp , Equilíbrio Postural/fisiologia , Córtex Somatossensorial/crescimento & desenvolvimento , Tálamo/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos , Percepção do Tato/fisiologia , Caminhada/fisiologia
14.
Am J Perinatol ; 34(2): 164-168, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27367285

RESUMO

Objective Determine whether the indication for intrauterine balloon tamponade (IUBT) is associated with failure rates. Study Design Cohort study of women who underwent IUBT for postpartum hemorrhage (PPH) from 2007 to 2014. The indication was categorized as uterine atony or placental-site bleeding. Primary outcome was IUBT failure, defined as the need for uterine artery embolization or hysterectomy. Secondary outcomes were estimated blood loss (EBL) after balloon placement, transfusion of red blood cells (RBC), transfusion of fresh frozen plasma (FFP) and/or cryoprecipitate, and intensive care unit (ICU) admission. Results 306 women underwent IUBT: 241 (78.8%) for uterine atony and 65 (21.2%) for placental site bleeding. Overall, 67 (21.9%) women experienced IUBT failure. The frequency of failure was similar in those with uterine atony compared with those with placental-site bleeding (21.2 vs 24.6%, p = 0.55). This finding persisted after adjusting for potential confounders (aOR, 0.97; 95% CI, 0.48-1.99). Median EBL after balloon placement (190 [interquartile range, 93-375] vs 195 [interquartile range, 103-500] mL, p = 0.46), and frequencies of RBC transfusion (62.7 vs 66.2%, p = 0.60), FFP and/or cryoprecipitate transfusion (25.3 vs 33.8%, p = 0.17), and ICU admission (12.4 vs 16.9%, p = 0.35) were also similar. Conclusion IUBT was similarly effective for managing PPH from uterine atony or placental-site bleeding.


Assuntos
Doenças Placentárias , Hemorragia Pós-Parto/etiologia , Hemorragia Pós-Parto/terapia , Tamponamento com Balão Uterino , Inércia Uterina , Adulto , Transfusão de Eritrócitos , Fator VIII/uso terapêutico , Feminino , Fibrinogênio/uso terapêutico , Humanos , Histerectomia , Unidades de Terapia Intensiva , Admissão do Paciente , Doenças Placentárias/terapia , Plasma , Gravidez , Retratamento , Estudos Retrospectivos , Falha de Tratamento , Embolização da Artéria Uterina , Inércia Uterina/terapia
15.
Materials (Basel) ; 17(14)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39063835

RESUMO

Quinacridone (QA) and 2,9-dimethylquinacridone (DQA) are synthetic substances suitable as a hard, abrasion-resistant, self-organizing gliding layer on ice and snow. For sustainable use, a large number of parameters must be considered to demonstrate that these non-biogenic substances and their by-products and degradation products are harmless to humans and the environment in the quantities released. For this task, available experimental data are used and supplemented for all tautomers by numerous relevant physical, chemical, toxicological and ecotoxicological estimated values based on various Quantitative Structure Activity Relationship (QSAR) methods. On the one hand, the low solubility of QA and DQA leads to stable gliding layers and thus, low abrasion and uptake by plants, animals and humans. On the other hand, the four hydrogen bond forming functional groups per molecule allow nanoparticle decomposition and enzymatic degradation in natural environments. All available data justify a sustainable use of QA and DQA as a gliding layer. The assessment of the toxicological properties is complemented by an investigation of the size and morphology of DQA particles, as well as field tests indicating excellent performance as a gliding layer on snow.

16.
Sci Data ; 11(1): 828, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068152

RESUMO

The composition and morphology of the cathode catalyst layer (CCL) have a significant impact on the performance and stability of polymer electrolyte membrane fuel cells (PEMFC). Understanding the primary degradation mechanism of the CCL and its influencing factors is crucial for optimizing PEMFC performance and durability. Within this work, we present comprehensive in-situ characterization data focused on cathode catalyst degradation. The dataset consists of 36 unique durability tests with over 4000 testing hours, including variations in the cathode ionomer to carbon ratio, platinum on carbon ratio, ionomer equivalent weight, and carbon support type. The applied accelerated stress tests were conducted with different upper potential limits and relative humidities. Characterization techniques including IV-curves, limiting current measurements, electrochemical impedance spectroscopy, and cyclic voltammetry were employed to analyse changes in performance, charge and mass transfer, and electrochemically active surface area of the catalyst. The aim of the dataset is to improve the understanding of catalyst degradation by allowing comparisons across material variations and provide practical information for other researchers in the field.

17.
Sci Rep ; 14(1): 634, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182625

RESUMO

Cardiovascular magnetic resonance (CMR)-derived hemodynamic force (HDF) analyses have been introduced recently enabling more in-depth cardiac function evaluation. Inter-study reproducibility is important for a widespread clinical use but has not been quantified for this novel CMR post-processing tool yet. Serial CMR imaging was performed in 11 healthy participants in a median interval of 63 days (range 49-87). HDF assessment included left ventricular (LV) longitudinal, systolic peak and impulse, systolic/diastolic transition, diastolic deceleration as well as atrial thrust acceleration forces. Inter-study reproducibility and study sample sizes required to demonstrate 10%, 15% or 20% relative changes of HDF measurements were calculated. In addition, intra- and inter-observer analyses were performed. Intra- and inter-observer reproducibility was excellent for all HDF parameters according to intraclass correlation coefficient (ICC) values (> 0.80 for all). Inter-study reproducibility of all HDF parameters was excellent (ICC ≥ 0.80 for all) with systolic parameters showing lower coeffients of variation (CoV) than diastolic measurements (CoV 15.2% for systolic impulse vs. CoV 30.9% for atrial thrust). Calculated sample sizes to detect relative changes ranged from n = 12 for the detection of a 20% relative change in systolic impulse to n = 200 for the detection of 10% relative change in atrial thrust. Overall inter-study reproducibility of CMR-derived HDF assessments was sufficient with systolic HDF measurements showing lower inter-study variation than diastolic HDF analyses.


Assuntos
Hemodinâmica , Imageamento por Ressonância Magnética , Humanos , Reprodutibilidade dos Testes , Átrios do Coração , Espectroscopia de Ressonância Magnética
18.
Infect Control Hosp Epidemiol ; : 1-3, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38741562

RESUMO

A healthcare-associated group A Streptococcus outbreak involving six patients, four healthcare workers, and one household contact occurred in the labor and delivery unit of an academic medical center. Isolates were highly related by whole genome sequencing. Infection prevention measures, healthcare worker screening, and chemoprophylaxis of those colonized halted further transmission.

19.
Sci Adv ; 9(33): eadh4030, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37595042

RESUMO

During the COVID-19 pandemic, the youth mental health crisis has reached unprecedented levels. To which extent school closures, one of the most heavily debated pandemic measures, have contributed to or even caused this crisis is largely unknown. We seek to narrow this blind spot, by combining quasi-experimental variation in school closure and reopening strategies across the German federal states at the onset of the pandemic with nationwide, population-based survey data on youth mental health and high-frequency data from the largest crisis helpline. We show that prolonged school closures led to a substantial deterioration in youth health-related quality of life, precipitating early signs of mental health problems. The effects were most severe among boys, younger adolescents, and families with limited living space. We further provide evidence that family problems are a major issue that adolescents were struggling with when denied access to school. Overall, school closures largely explain the deterioration of youth mental health over the first pandemic wave.


Assuntos
COVID-19 , Saúde Mental , Masculino , Humanos , Adolescente , Pandemias , Qualidade de Vida , COVID-19/epidemiologia , Instituições Acadêmicas
20.
J Perinatol ; 43(11): 1440-1445, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37783851

RESUMO

OBJECTIVE: This study examines improvement in birth certificate accuracy during a statewide quality improvement initiative. STUDY DESIGN: Participating hospitals systematically sampled 10 delivery medical records per month and compared them to corresponding birth certificates for accuracy. Accuracy was computed before implementing the initiative (Aug-Oct 2014), end of phase 1 (July 2015) and end of phase 2 (Nov-Dec 2015). Accuracy data was aggregated and compared across time points using a linear mixed model and by hospital characteristics. RESULTS: 105 hospitals participated. Birth certificate accuracy increased between baseline (89.59%) and end of phase 2 (97.00%, p < 0.001). Percent accuracy at baseline was lowest in hospitals serving at-risk populations (p < 0.01). These hospitals showed relatively greater increases in overall accuracy with no difference in accuracy by the end of the initiative. CONCLUSIONS: A statewide QI effort contributed to improvements in birth certificate accuracy. Hospitals serving at-risk populations exhibited the greatest benefit and improvement.


Assuntos
Declaração de Nascimento , Melhoria de Qualidade , Humanos , Illinois , Prontuários Médicos , Hospitais
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