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1.
JAMA Health Forum ; 5(3): e240198, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517423

RESUMO

Importance: On January 1, 2022, New Mexico implemented a No Behavioral Cost-Sharing (NCS) law that eliminated cost-sharing for mental health and substance use disorder (MH/SUD) treatments in plans regulated by the state, potentially reducing a barrier to treatment for MH/SUDs among the commercially insured; however, the outcomes of the law are unknown. Objective: To assess the association of implementation of the NCS with out-of-pocket spending for prescription for drugs primarily used to treat MH/SUDs and monthly volume of dispensed drugs. Design, Settings, and Participants: This retrospective cohort study used a difference-in-differences research design to examine trends in outcomes for New Mexico state employees, a population affected by the NCS, compared with federal employees in New Mexico who were unaffected by NCS. Data were collected on prescription drugs for MH/SUDs dispensed per month between January 2021 and June 2022 for New Mexico patients with a New Mexico state employee health plan and New Mexico patients with a federal employee health plan. Data analysis occurred from December 2022 to January 2024. Exposure: Enrollment in a state employee health plan or federal health plan. Main Outcomes and Measures: The primary outcomes were mean patient out-of-pocket spending per dispensed MH/SUD prescription and the monthly volume of dispensed MH/SUD prescriptions per 1000 employees. A difference-in-differences estimation approach was used. Results: The implementation of the NCS law was associated with a mean (SE) $6.37 ($0.30) reduction (corresponding to an 85.6% decrease) in mean out-of-pocket spending per dispensed MH/SUD medication (95% CI, -$7.00 to -$5.75). The association of implementation of NCS with the volume of prescriptions dispensed was not statistically significant. Conclusions and Relevance: These findings suggest that the implementation of the New Mexico NCS law was successful in lowering out-of-pocket spending on prescription medications for MH/SUDs, but that there was no association of NCS with the volume of medications dispensed in the first 6 months after implementation. A key challenge is to identify policies that protect from high out-of-pocket spending while also promoting access to needed care.


Assuntos
Medicamentos sob Prescrição , Transtornos Relacionados ao Uso de Substâncias , Humanos , Medicamentos sob Prescrição/uso terapêutico , Estudos Retrospectivos , Custo Compartilhado de Seguro , Gastos em Saúde , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Custos de Cuidados de Saúde
2.
Nat Commun ; 14(1): 3044, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37236971

RESUMO

Multiphase flows involving granular materials are complex and prone to pattern formation caused by competing mechanical and hydrodynamic interactions. Here we study the interplay between granular bulldozing and the stabilising effect of viscous pressure gradients in the invading fluid. Injection of aqueous solutions into layers of dry, hydrophobic grains represent a viscously stable scenario where we observe a transition from growth of a single frictional finger to simultaneous growth of multiple fingers as viscous forces are increased. The pattern is made more compact by the internal viscous pressure gradient, ultimately resulting in a fully stabilised front of frictional fingers advancing as a radial spoke pattern.

3.
Cryst Growth Des ; 22(4): 2433-2440, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35401053

RESUMO

We use high-speed photography to observe the dendritic freezing of ice between two closely spaced parallel plates. Measuring the propagation speeds of dendrites, we investigate whether there is a confinement-induced thermal influence upon the speed beyond that provided by a single surface. Plates of thermally insulating plastic and moderately thermally conductive glass are used alone and in combination, at temperatures between -10.6 and -4.8 °C, with separations between 17 and 135 µm wide. No effect of confinement was detected for propagation on glass surfaces, but a possible slowing of propagation speed was seen between insulating plates. The pattern of dendritic growth was also studied, with a change from curving to straight dendrites being strongly associated with a switch from a glass to a plastic substrate.

4.
Proc Natl Acad Sci U S A ; 118(18)2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33903239

RESUMO

The nucleation of ice crystals in clouds is poorly understood, despite being of critical importance for our planet's climate. Nucleation occurs largely at rare "active sites" present on airborne particles such as mineral dust, but the nucleation pathway is distinct under different meteorological conditions. These give rise to two key nucleation pathways where a particle is either immersed in a supercooled liquid water droplet (immersion freezing mode) or suspended in a supersaturated vapor (deposition mode). However, it is unclear if the same active sites are responsible for nucleation in these two modes. Here, we directly compare the sites that are active in these two modes by performing immersion freezing and deposition experiments on the same thin sections of two atmospherically important minerals (feldspar and quartz). For both substrates, we confirm that nucleation is dominated by a limited number of sites and show that there is little correlation between the two sets of sites operating in each experimental method: across both materials, only six out of 73 sites active for immersion freezing nucleation were also active for deposition nucleation. Clearly, different properties determine the activity of nucleation sites for each mode, and we use the pore condensation and freezing concept to argue that effective deposition sites have size and/or geometry requirements not of relevance to effective immersion freezing sites. Hence, the ability to nucleate is pathway dependent, and the mode of nucleation has to be explicitly considered when applying experimental data in cloud models.

5.
Phys Rev Lett ; 120(16): 165701, 2018 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-29756921

RESUMO

Nucleation of ice from vapor on atmospheric aerosols has been attributed to the condensation and freezing of supercooled water in small pores. Here we use wedge pores on mica to directly observe the growth of ice in confinement prior to the growth of bulk crystals. We report a transition in behavior with a decreasing temperature: At low temperatures, the limiting step is not nucleation but a free energy barrier associated with the growth of ice through a narrow pore mouth to become a bulk phase.

6.
ACS Appl Mater Interfaces ; 10(19): 16893-16900, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29694020

RESUMO

Precise measurement of contact angles is an important challenge in surface science, in the design and characterization of materials and in many crystallization experiments. Here we present a novel technique for measuring the contact angles of droplets between about 2° and 30°, with the lowest experimental uncertainty at the lower end of this range, typically ±0.1°. The lensing effect of a droplet interface produces the appearance of bright circles in low-aperture light, whose diameter is related to the contact angle. The technique requires no specialized equipment beyond an ordinary optical microscope, and may be used to study the dynamic evolution of the contact angle in situ during an experiment.

7.
Langmuir ; 33(19): 4870-4877, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28459594

RESUMO

The thermal influence of a solid wall on the solidification of a sessile supercooled water drop is experimentally investigated. The velocity of the initial ice layer propagating along the solid substrate prior to dendritic solidification is determined from videos captured using a high-speed video system. Experiments are performed for varying substrate materials and liquid supercooling. In contrast to recent studies at moderate supercooling, in the case of metallic substrates only a weak influence of the substrate's thermal properties on the ice layer velocity is observed. Using the analytical solution of the two-phase Stefan problem, a semiempirical model for the ice layer velocity is developed. The experimental data are well described for all supercooling levels in the entire diffusion limited solidification regime. For higher supercooling, the model overestimates the freezing velocity due to kinetic effects during molecular attachment at the solid-liquid interface, which are not accounted for in the model. The experimental findings of the present work offer a new perspective on the design of anti-icing systems.

8.
Proc Natl Acad Sci U S A ; 114(5): 810-815, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-27994140

RESUMO

Heterogeneous nucleation is vital to a wide range of areas as diverse as ice nucleation on atmospheric aerosols and the fabrication of high-performance thin films. There is excellent evidence that surface topography is a key factor in directing crystallization in real systems; however, the mechanisms by which nanoscale pits and pores promote nucleation remain unclear. Here, we use natural cleavage defects on Muscovite mica to investigate the activity of topographical features in the nucleation from vapor of ice and various organic crystals. Direct observation of crystallization within surface pockets using optical microscopy and also interferometry demonstrates that these sharply acute features provide extremely effective nucleation sites and allows us to determine the mechanism by which this occurs. A confined phase is first seen to form along the apex of the wedge and then grows out of the pocket opening to generate a bulk crystal after a threshold saturation has been achieved. Ice nucleation proceeds in a comparable manner, although our resolution is insufficient to directly observe a condensate before the growth of a bulk crystal. These results provide insight into the mechanism of crystal deposition from vapor on real surfaces, where this will ultimately enable us to use topography to control crystal deposition on surfaces. They are also particularly relevant to our understanding of processes such as cirrus cloud formation, where such topographical features are likely candidates for the "active sites" that make clay particles effective nucleants for ice in the atmosphere.

9.
Nat Mater ; 14(8): 780-784, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26030304

RESUMO

Atomic-level defects such as dislocations play key roles in determining the macroscopic properties of crystalline materials. Their effects range from increased chemical reactivity to enhanced mechanical properties. Dislocations have been widely studied using traditional techniques such as X-ray diffraction and optical imaging. Recent advances have enabled atomic force microscopy to study single dislocations in two dimensions, while transmission electron microscopy (TEM) can now visualize strain fields in three dimensions with near-atomic resolution. However, these techniques cannot offer three-dimensional imaging of the formation or movement of dislocations during dynamic processes. Here, we describe how Bragg coherent diffraction imaging (BCDI; refs 11, 12) can be used to visualize in three dimensions, the entire network of dislocations present within an individual calcite crystal during repeated growth and dissolution cycles. These investigations demonstrate the potential of BCDI for studying the mechanisms underlying the response of crystalline materials to external stimuli.

10.
Int J Cell Biol ; 2014: 495817, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24729786

RESUMO

Intracerebral hemorrhage (ICH) is the most common form of hemorrhagic stroke, accounting for 15% of all strokes. ICH has the highest acute mortality and the worst long-term prognosis of all stroke subtypes. Unfortunately, the dearth of clinically effective treatment options makes ICH the least treatable form of stroke, emphasizing the need for novel therapeutic targets. Recent work by our laboratory identified a novel role for the necroptosis inhibitor, necrostatin-1, in limiting neurovascular injury in tissue culture models of hemorrhagic injury. In the present study, we tested the hypothesis that necrostatin-1 reduces neurovascular injury after collagenase-induced ICH in mice. Necrostatin-1 significantly reduced hematoma volume by 54% at 72 h after-ICH, as compared to either sham-injured mice or mice administered an inactive, structural analogue of necrostatin-1. Necrostatin-1 also limited cell death by 48%, reduced blood-brain barrier opening by 51%, attenuated edema development to sham levels, and improved neurobehavioral outcomes after ICH. These data suggest a potential clinical utility for necrostatin-1 and/or novel necroptosis inhibitors as an adjunct therapy to reduce neurological injury and improve patient outcomes after ICH.

11.
Rev Med Chil ; 141(5): 602-8, 2013 May.
Artigo em Espanhol | MEDLINE | ID: mdl-24089275

RESUMO

BACKGROUND: The neutrophil/lymphocyte ratio is an effective marker of inflammation ana can have prognostic value in surgical patients. AIM: To evaluate the effect of an increased neutrophil/lymphocyte ratio (NLR) on perioperative complications ana overall ana disease-free survival in patients undergoing elective resection for stage II colon cancer. MATERIAL AND METHODS: Data was obtained from clinical charts, preoperative blood results and hospital records of all patients undergoing an elective curative resection for colon cancer, between 2000 and 2007. Preoperative NLR was calculated. Follow-up was obtained from a prospectively maintained colorectal cancer database, clinical records and questionnaires. Uni and multivariable analysis were performed to identify associations, and survival analysis was performed using Kaplan-Meier curves. RESULTS: One hundred twenty two patients with a mean age of 69 years (52% males), were evaluated. Median follow-up was 73 months, and overall survival for 1 and 5 years was 95% and 68%, respectively. On a multivariable analysis after adjusting for age, sex, tumor depth invasion, use of adjuvant therapies and American Society of Anesthesiology preoperative risk score, an NLR > 5 was associated with an increased perioperative complication rate (odds ratio: 3.06, p = 0.033). Kaplan-Meier survival analysis showed a worse overall and disease-free survival for patients with NLR greater than five. CONCLUSIONS: A preoperative NLR of five or more is associated with greater perioperative morbidity and worse oncological outcomes in patients undergoing resection for elective stage II colon cancer.


Assuntos
Neoplasias do Colo/sangue , Linfócitos , Neutrófilos , Idoso , Neoplasias do Colo/mortalidade , Neoplasias do Colo/cirurgia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Contagem de Leucócitos , Masculino , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico
12.
Rev. méd. Chile ; 141(5): 602-608, mayo 2013. graf, tab
Artigo em Espanhol | LILACS | ID: lil-684368

RESUMO

Background: The neutrophil/lymphocyte ratio is an effective marker of inflammation ana can have prognostic value in surgical patients. Aim: To evaluate the effect of an increased neutrophil/lymphocyte ratio (NLR) on perioperative complications ana overall ana disease-free survival in patients undergoing elective resection for stage II colon cancer. Material and Methods: Data was obtained from clinical charts, preoperative blood results and hospital records of all patients undergoing an elective curative resection for colon cancer, between 2000 and 2007. Preoperative NLR was calculated. Follow-up was obtained from a prospectively maintained colorectal cancer database, clinical records and questionnaires. Uni and multivariable analysis were performed to identify associations, and survival analysis was performed using Kaplan-Meier curves. Results: One hundred twenty two patients with a mean age of69years (52% males), were evaluated. Median follow-up was 73 months, and overall survival for 1 and 5years was 95% and 68%, respectively. On a multivariable analysis after adjusting for age, sex, tumor depth invasion, use of adjuvant therapies and American Society of Anesthesiology preoperative risk score, an NLR > 5 was associated with an increased perioperative complication rate (odds ratio: 3,06, p = 0,033). Kaplan-Meier survival analysis showed a worse overall and disease-free survival for patients with NLR greater than five. Conclusions: A preoperative NLR of five or more is associated with greater perioperative morbidity and worse oncological outcomes in patients undergoing resection for elective stage II colon cancer.


Assuntos
Idoso , Feminino , Humanos , Masculino , Neoplasias do Colo/sangue , Linfócitos , Neutrófilos , Neoplasias do Colo/mortalidade , Neoplasias do Colo/cirurgia , Intervalo Livre de Doença , Seguimentos , Estimativa de Kaplan-Meier , Contagem de Leucócitos , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico
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