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1.
Adv Mater ; : e2402070, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616493

RESUMO

Future pulsed-power electronic systems based on dielectric capacitors require the use of environment-friendly materials with high energy-storage performance that can operate efficiently and reliably in harsh environments. Here, a study of multilayer structures, combining paraelectric-like Ba0.6Sr0.4TiO3 (BST) with relaxor-ferroelectric BaZr0.4Ti0.6O3 (BZT) layers on SrTiO3-buffered Si substrates, with the goal to optimize the high energy-storage performance is presented. The energy-storage properties of various stackings are investigated and an extremely large maximum recoverable energy storage density of ≈165.6 J cm-3 (energy efficiency ≈ 93%) is achieved for unipolar charging-discharging of a 25-nm-BZT/20-nm-BST/910-nm-BZT/20-nm-BST/25-nm-BZT multilayer structure, due to the extremely large breakdown field of 7.5 MV cm-1 and the lack of polarization saturation at high fields in this device. Strong indications are found that the breakdown field of the devices is determined by the outer layers of the multilayer stack and can be increased by improving the quality of these layers. Authors are also able to deduce design optimization rules for this material combination, which can be to a large extend justify by structural analysis. These rules are expected also to be useful for optimizing other multilayer systems and are therefore very relevant for further increasing the energy storage density of capacitors.

2.
Alcohol Treat Q ; 41(3): 309-321, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37519928

RESUMO

Behavioral economic theory of addiction proposes that substance use often takes place in environments with limited substance-free reinforcement. While increasing substance-free reinforcement is known to reduce substance use, systematic efforts to boost substance-free reinforcement is not often a focus of most alcohol treatment programs. Participants (N=21) with alcohol use disorder participated in virtual focus group sessions. Qualitative content analysis was conducted on participants' verbatim responses. Substance-free activities were also assessed with a 66-item modified pleasant activity list specifying activity engagement frequency and enjoyment. All participants reported introduction to substance-free activity engagement as part of their treatment, although those in group therapy (relative to individual) reported less consistent support. While motives for initial activity engagement were reported as stemming from external sources (i.e., therapist), activity maintenance was linked to intrinsic motives (i.e., personal interest). All participants identified substance-free activities as a key aid to successful recovery. Types of most helpful activities were ones related to self-care, social connections, acts of service, and creative outlets. Findings are consistent with theories of behavior change and suggest participants believe substance-free activity engagement is an important component of their recovery, however they are not receiving consistent support during the pivotal early recovery period.

3.
Aesthetic Plast Surg ; 46(2): 907-911, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34767060

RESUMO

With the increase of cosmetic injectable hyaluronic acid (HA), there have been more cases with serious complications, including skin necrosis, blindness, and cerebral embolism. Patients who have recovered from HA filler-induced total vision loss are extremely rare. We report a case of a 27-year-old female who developed severe ocular pain on the right side and total vision loss following a 1.0 ml HA filler injection in the nasal dorsum. She arrived at our hospital 4 hours later. Her visual acuity was no light perception (NLP), and she exhibited eyelid ptosis, ophthalmoplegia, and frontal and nasal ecchymosis. She was promptly treated with subcutaneous and retrobulbar hyaluronidase injections, as well as intra-arterial 1500 IU hyaluronidase injections into the right ophthalmic artery with DSA assistance. Her vision improved from NLP to counting fingers at 1.0 meters. Unfortunately, 13 hours later, she felt an intense headache, and her vision again decreased to NLP. We immediately performed an injection of 1500 IU hyaluronidase combined with 8 mg alteplase for intra-arterial thrombolysis (IAT) into the right ophthalmic artery. Her vision improved immediately afterward. After 3 months, her visual acuity had significantly recovered from NLP (admission vision status) to 20/50 (Snellen chart with glasses). Similarly, skin, conjunctival, eye movement, and ptosis symptoms completely recovered. This case demonstrates that reversal of complete blindness due to embolism of the ophthalmic and central retinal arteries could be accomplished through multidisciplinary therapies, especially IAT using fibrinolytic agents combined with hyaluronidase followed by an anticoagulant regimen.Level of evidence VThis journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .


Assuntos
Técnicas Cosméticas , Preenchedores Dérmicos , Adulto , Cegueira/etiologia , Técnicas Cosméticas/efeitos adversos , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Ácido Hialurônico/efeitos adversos , Hialuronoglucosaminidase , Injeções Intra-Arteriais
4.
Materials (Basel) ; 14(21)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34771973

RESUMO

The dielectric properties, tunability and figure-of-merit (FOM) of relaxor Pb0.9La0.1(Zr0.52Ti0.48)O3 (PLZT) films have been investigated. Dielectric measurements indicated that the dielectric constant (at zero-bias field), tunability and FOM are enhanced as the film thickness increases, which are mainly attributed to the presence of an interfacial layer near the film-electrode interface. Experimental results illustrated that a slight reduction is observed in both dielectric constant and tunability (-2%) in a wide-frequency range (10 kHz-1 MHz); meanwhile, the FOM value decreases significantly (-17%) with increasing frequency, arising from the higher dielectric loss value. The 1000-nm PLZT film shows the largest tunability of 94.6% at a maximum electric-field of 1450 kV/cm, while the highest FOM factor is 37.6 at 1000 kV/cm, due to the combination of medium tunability (88.7%) and low dielectric loss (0.0236). All these excellent results indicated that the relaxor PLZT films are promising candidates for specific applications in microwave devices.

5.
Drug Alcohol Depend ; 227: 108978, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488078

RESUMO

OBJECTIVES: Gender differences in the prevalence of opioid misuse continue to evolve and have not been well characterized in recent years. Our objective was to investigate gender differences in the prevalence of opioid misuse and use disorder in the US over the 5-year period from 2015 to 2019. METHODS: We used annual survey data from the 2015-2019 National Survey on Drug Use and Health to estimate gender differences in the prevalence of opioid misuse. We examined past-year opioid analgesic misuse initiation, opioid analgesic misuse, heroin use, opioid analgesic use disorder and heroin use disorder. Logistic regression models were used to test gender differences, adjusting for sociodemographic variables. RESULTS: In adjusted analyses, women had higher odds of having initiated opioid analgesic misuse in the past year compared to men. In contrast, men had higher odds of misuse of opioid analgesics, heroin use, and an opioid analgesic or heroin use disorder. CONCLUSIONS: Although opioid misuse has historically been more prevalent in men, the gender difference in opioid analgesic misuse continues to narrow, with more women initiating misuse than men including higher rates of misuse in adolescent girls. Heroin use continues to be approximately twice as common in men as women.


Assuntos
Transtornos Relacionados ao Uso de Opioides , Uso Indevido de Medicamentos sob Prescrição , Adolescente , Analgésicos Opioides , Feminino , Heroína , Humanos , Masculino , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Prevalência , Fatores Sexuais , Estados Unidos/epidemiologia
6.
Harv Rev Psychiatry ; 28(5): 305-315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925513

RESUMO

A growing evidence base supports the use of medication to treat opioid use disorder (OUD) in adolescents, but little is known about behavioral therapies for adolescents with OUD. A systematic review using PRISMA methodology was conducted on behavioral therapy for adolescent OUD. Only three studies were identified. Combined evidence from two studies indicates initial efficacy of the Adolescent-Community Reinforcement Approach, motivational enhancement therapy, and cognitive-behavioral therapy for reducing opioid use. The only group therapy identified, which involved adolescents and their parents, demonstrated improvement in participants' knowledge of relapse-prevention strategies, drug-refusal skills, and overall psychosocial functioning. Additional studies that included behavioral therapy but that did not specifically test its efficacy are also highlighted to expand the understanding of the small literature base. This review highlights the sparse evidence base for these therapies in this population. In addition, we highlight promising areas for future research and include evidence from the adult literature that may inform that research. Studies on behavioral therapies that utilize randomized, controlled trials for this population are imperative.


Assuntos
Terapia Comportamental/métodos , Transtornos Relacionados ao Uso de Opioides/terapia , Adolescente , Aconselhamento , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Transtornos Relacionados ao Uso de Opioides/psicologia , Pais/psicologia
7.
J Pers Med ; 10(3)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32933040

RESUMO

This study examines the IGF serum profile (IGF-1, IGFBP-3 and the IGF Ratio) from 1633 women who undertook an Assessment Cycle prior to any treatment by assisted reproduction. The idea is to progressively study the IGF profile with a view to identify those women who may be classified as having adult growth hormone deficiency (AGHD) and who may benefit from specific dynamic endocrinological testing to identify a potential benefit from growth hormone adjuvant treatment. This first study evaluates the IGF profile on clinical parameters, namely age, body mass index (BMI) and stature. The study shows a significant linear reduction in IGF-1 levels across the four age groups (<35 years, 35-39 years, 40-44 years and ≥45 years; p < 0.001). However, there was no variation in IGFBP-3 levels but the IGF Ratio showed a progressive linear elevation with advancing age (p < 0.001). With respect to both BMI and stature, none of the IGF profile parameters showed any variation. We conclude that further studies are warranted to examine the notion of underlying AGHD in the causation of the well-known feature of age-related poor prognosis in assisted reproduction.

8.
Health Psychol ; 39(9): 806-814, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32833482

RESUMO

OBJECTIVES: More than 2 million people in the United States had an opioid use disorder in 2017. Treatment for opioid use disorder-particularly medication combined with psychosocial support-is effective for reducing opioid use and decreasing overdose risk. However, approximately 50% of people who receive treatment will relapse or drop out. Stress reactivity, defined as the subjective and physiological response to stress, is heightened in people with opioid use disorder and higher stress reactivity is associated with poorer outcomes. Preliminary studies suggest that stress reactivity may be a key mechanistic target for improving outcomes. This article describes the design of an ongoing study examining behavioral strategies for reducing stress reactivity in adults with opioid use disorder. Our objective is to test the efficacy of two behavioral strategies for reducing stress reactivity and enhancing behavioral persistence in the context of stress (distress tolerance). METHOD: We will recruit 120 adults with opioid use disorder and randomly assign them to brief training in (a) cognitive reappraisal, (b) affect labeling, or (c) a psychoeducational control. Participants will receive the training intervention followed by a laboratory stressor during which they will be instructed to apply the trained skill. RESULTS: Subjective and physiological responses to stress will be measured as indices of stress reactivity and the stressor task will include a behavioral persistence component as a measure of distress tolerance. CONCLUSIONS: The ultimate goal of this study is to inform the development of behavioral interventions that can be used as an adjunct to medication-based treatment for opioid use disorder. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Transtornos Relacionados ao Uso de Opioides/psicologia , Estresse Psicológico/psicologia , Feminino , Humanos , Masculino , Projetos de Pesquisa
9.
ACS Appl Mater Interfaces ; 11(44): 41402-41414, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31618576

RESUMO

This work demonstrates the influence of high-quality protection layers on Si-Cu2O micropillar arrays created by pulsed laser deposition (PLD), with the goal to overcome photodegradation and achieve long-term operation during photoelectrochemical (PEC) water splitting. Sequentially, we assessed planar and micropillar device designs with various design parameters and their influence on PEC hydrogen evolution reaction. On the planar device substrates, a Cu2O film thickness of 600 nm and a Cu2O/CuO heterojunction layer with a 5:1 thickness ratio between Cu2O to CuO were found to be optimal. The planar Si/Cu2O/CuO heterostructure showed a higher PV performance (Jsc = 20 mA/cm2) as compared to the planar Si/Cu2O device, but micropillar devices did not show this improvement. Multifunctional overlayers of ZnO (25 nm) and TiO2 (100 nm) were employed by PLD on Si/Cu2O planar and micropillar arrays to provide a hole-selective passivation layer that acts against photocorrosion. A micropillar Si/ITO-Au/Cu2O/ZnO/TiO2/Pt stack was compared to a planar device. Under optimized conditions, the Si/Cu2O photocathode with Pt as a HER catalyst displayed a photocurrent of 7.5 mA cm-2 at 0 V vs RHE and an onset potential of 0.85 V vs RHE, with a stable operation for 75 h.

10.
Org Lett ; 21(6): 1708-1712, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30807194

RESUMO

Visible-light-induced generation of dithianyl and dioxolanyl radicals via selective hydrogen atom transfer (HAT) has been achieved. This radical relay tactic enables remote C(sp3)-H functionalization to permit rapid access to polyol and spiroketal segments, and in turn has been exploited as a key synthetic construct in the total synthesis of the danshenspiroketallactones. The conformational stability of the danshenspiroketallactones has also been defined via experiments and DFT calculations.


Assuntos
Hidrogênio/química , Polímeros/química , Catálise , Luz , Estrutura Molecular , Processos Fotoquímicos
11.
Congenit Anom (Kyoto) ; 58(4): 124-129, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29030958

RESUMO

To evaluate the association between the single nucleotide polymorphism (SNP) rs227493 in the MEOX2 gene and nonsyndromic cleft palate only, this research was conducted as a case-control study by comparing a nonsyndromic cleft palate only group with an independent, healthy, and unaffected control group who were both examined by specialists. Based on clinical examination and medical records, we analyzed a total of 570 DNA samples, including 277 cases and 293 controls, which were extracted from dry blood spot samples collected from both the Odonto and Maxillofacial Hospital in Ho Chi Minh City and Nguyen Dinh Chieu Hospital in Ben Tre province, respectively. The standard procedures of genotyping the specific SNP (rs2237493) for MEOX2 were performed on a StepOne Realtime PCR system with TaqMan SNP Genotyping Assays. Significant statistical differences were observed in allelic frequencies (allele T and allele G) between the non-syndromic cleft palate only and control groups in female subjects, with an allelic odds ratio of 1.455 (95% confidence interval: 1.026-2.064) and P < 0.05. These study findings suggest that nonsyndromic isolated cleft palate might be influenced by variation of MEOX2, especially SNP rs2237493 in Vietnamese females.


Assuntos
Povo Asiático/genética , Fenda Labial/genética , Fissura Palatina/genética , Proteínas de Homeodomínio/genética , Polimorfismo de Nucleotídeo Único , Estudos de Casos e Controles , Fenda Labial/epidemiologia , Fissura Palatina/epidemiologia , Feminino , Genótipo , Humanos , Masculino , Vietnã/epidemiologia
12.
Sci Rep ; 7(1): 12915, 2017 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-29018287

RESUMO

Thin films of PbZr0.52Ti0.48O3 (PZT) with largely detached columnar grains, deposited by pulsed laser deposition (PLD) on amorphous glass substrates covered with Ca2Nb3O10 nanosheets as growth template and using LaNiO3 electrode layers, are shown to exhibit very high unipolar piezoelectric strain and ultra-low strain hysteresis. The observed increase of the piezoelectric coefficient with increasing film thickness is attributed to the reduction of clamping, because of the increasingly less dense columnar microstructure (more separation between the grains) with across the film thickness. A very large piezoelectric coefficient (490 pm/V) and a high piezoelectric strain (~0.9%) are obtained in 4-µm-thick film under an applied electric field of 200 kV/cm, which is several times larger than in usual PZT ceramics. Further very low strain hysteresis (H≈2-4%) is observed in 4 to 5 µm thick films. These belong to the best values demonstrated so far in piezoelectric films. Fatigue testing shows that the piezoelectric properties are stable up to 1010 cycles. The growth of high quality PZT films with very large strain and piezoelectric coefficients, very low hysteresis and with long-term stability on a technologically important substrate as glass is of great significance for the development of practical piezo driven microelectromechanical actuator systems.

13.
ACS Appl Mater Interfaces ; 9(41): 35947-35957, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28952313

RESUMO

Nanosheet Ca2Nb3O10 (CNOns) layers were deposited on ultralow expansion glass substrates by the Langmuir-Blodgett method to obtain preferential (001)-oriented growth of Pb(Zr0.52Ti0.48)O3 (PZT) thin films using pulsed laser deposition (PLD) to enhance the ferroelectric and piezoelectric properties of the films. The PLD deposition temperature and repetition frequency used for the deposition of the PZT films were found to play a key role in the precise control of the microstructure and therefore of the ferroelectric and piezoelectric properties. A film deposited at a high repetition frequency has a columnar grain structure, which helps to increase the longitudinal piezoelectric coefficient (d33f). An enhanced d33f value of 356 pm V-1 was obtained for 2-µm-thick PZT films on CNOns/glass substrates. This high value is ascribed to the preferential alignment of the crystalline [001] axis normal to the substrate surface and the open columnar structure. Large displacement actuators based on such PZT films grown on CNOns/glass substrates should be useful in smart X-ray optics applications.

14.
ACS Appl Mater Interfaces ; 9(11): 9849-9861, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28247756

RESUMO

Pb(Zr0.52Ti0.48)O3 (PZT) films with (001) orientation were deposited on Pt(111)/Ti/SiO2/Si(100) substrates using pulsed laser deposition. Variation of the laser pulse rate during the deposition of the PZT films was found to play a key role in the control of the microstructure and to change strongly the piezoelectric response of the thin film. The film deposited at low pulse rate has a denser columnar microstructure, which improves the transverse piezoelectric coefficient (d31f) and ferroelectric remanent polarization (Pr), whereas the less densely packed columnar grains in the film deposited at high pulse rates give rise to a significantly higher longitudinal piezoelectric coefficient (d33f) value. The effect of film thickness on the ferroelectric and piezoelectric properties of the PZT films was also investigated. With increasing film thickness, the grain column diameter gradually increases, and also the average Pr and d33f values become larger. The largest piezoelectric coefficient of d33f = 408 pm V-1 was found for a 4-µm film thickness. From a series of films in the thickness range 0.5-5 µm, the z-position dependence of the piezoelectric coefficient could be deduced. A local maximum value of 600 pm V-1 was deduced in the 3.5-4.5 µm section of the thickest films. The dependence of the film properties on film thickness is attributed to the decreasing effect of the clamping constraint imposed by the substrate and the increasing spatial separation between the grains with increasing film thickness.

15.
Sci Technol Adv Mater ; 17(1): 45-57, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27877857

RESUMO

Epitaxial (PbMg1/3Nb2/3O3)2/3-(PbTiO3)1/3 (PMN-PT) films with different out-of-plane orientations were prepared using a CeO2/yttria stabilized ZrO2 bilayer buffer and symmetric SrRuO3 electrodes on silicon substrates by pulsed laser deposition. The orientation of the SrRuO3 bottom electrode, either (110) or (001), was controlled by the deposition conditions and the subsequent PMN-PT layer followed the orientation of the bottom electrode. The ferroelectric, dielectric and piezoelectric properties of the (SrRuO3/PMN-PT/SrRuO3) ferroelectric capacitors exhibit orientation dependence. The properties of the films are explained in terms of a model based on polarization rotation. At low applied fields domain switching dominates the polarization change. The model indicates that polarization rotation is easier in the (110) film, which is ascribed to a smaller effect of the clamping on the shearing of the pseudo-cubic unit cell compared to the (001) case.

16.
ACS Appl Mater Interfaces ; 8(45): 31120-31127, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-27782380

RESUMO

Ca2Nb3O10 (CNOns) and Ti0.87O2 (TiOns) metal oxide nanosheets (ns) are used as a buffer layer for epitaxial growth of piezoelectric capacitor stacks on Si and Pt/Ti/SiO2/Si (Pt/Si) substrates. Highly (001)- and (110)-oriented Pb(Zr0.52Ti0.48)O3 (PZT) films are achieved by utilizing CNOns and TiOns, respectively. The piezoelectric capacitors are characterized by polarization and piezoelectric hysteresis loops and by fatigue measurements. The devices fabricated with SrRuO3 top and bottom electrodes directly on nanosheets/Si have ferroelectric and piezoelectric properties well comparable with devices that use more conventional oxide buffer layers (stacks) such as YSZ, CeO2/YSZ, or SrTiO3 on Si. The devices grown on nanosheets/Pt/Si with Pt top electrodes show significantly improved polarization fatigue properties over those of similar devices grown directly on Pt/Si. The differences in properties are ascribed to differences in the crystalline structures and the density of the films. These results show a route toward the fabrication of single crystal piezoelectric thin films and devices with high quality, long-lifetime piezoelectric capacitor structures on nonperovskite and even noncrystalline substrates such as glass or polished metal surfaces.

18.
Consult Pharm ; 28(12): 800-3, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24322964

RESUMO

As life expectancy increases, it is imperative that health care providers recognize the importance of safe medication use within an aging geriatric population. Dealing with a cohort that has different biological and medical demands requires pharmacists to pay particular attention to details when treating this subset of individuals. In particular, this manuscript will focus on Alzheimer's disease (AD) and considerations when dealing with new treatment options. The Food and Drug Administration's recent approval of the increased dosage strength, donepezil 23 mg, previously only available in 5 mg and 10 mg strengths, has raised efficacy and safety concerns. Reservations stem from unproven superiority along with an increased incidence of adverse events. The purpose of the manuscript is to provide a brief insight into these concerns and provide readers the knowledge necessary to make a clinically sound decision when treating patients with moderate-to-severe AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/administração & dosagem , Indanos/administração & dosagem , Nootrópicos/administração & dosagem , Piperidinas/administração & dosagem , Inibidores da Colinesterase/efeitos adversos , Donepezila , Humanos , Indanos/efeitos adversos , Nootrópicos/efeitos adversos , Piperidinas/efeitos adversos , Resultado do Tratamento
19.
Sci Technol Adv Mater ; 14(4): 045006, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27877599

RESUMO

Piezoelectric thin films of PbZr0.45Ti0.55O3 were grown on Si substrates in four different ways, resulting in different crystalline structures, as determined by x-ray analysis. The crystalline structures were different in the spread in tilt angle and the in-plane alignment of the crystal planes between different grains. It is found that the deviations of the ferroelectric polarization loop from that of the ideal rectangular loop (reduction of the remanent polarization with respect to the saturation polarization, dielectric constant of the film, slanting of the loop, coercive field value) all scale with the average tilt angle. A model is derived based on the assumption that the tilted grain boundaries between grains affect the film properties locally. This model describes the observed trends. The effective piezoelectric coefficient d33,eff shows also a weak dependence on the average tilt angle for films grown in a single layer, whereas it is strongly reduced for the films deposited in multiple layers. The least affected properties are obtained for the most epitaxial films, i.e. grown on a SrTiO3 epitaxial seed layer, by pulsed laser deposition. These films are intrinsically stable and do not require poling to acquire these stable properties.

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