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1.
Front Psychiatry ; 14: 1248541, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645634

RESUMO

Background: Although the COVID-19 pandemic has greatly changed the way students studied, it is still unknown about the impact of the COVID-19 pandemic on students' academic performance and mental health. Objective: To explore the academic performance and mental health status of middle and high school students after the lifting of COVID-19 restrictions in China. Methods: An online survey was conducted in Sichuan province, China from Dec 14, 2022 to Feb 28, 2023. All participants were students in middle and high schools, recruited via their teachers. The general information, COVID-19-related information, and academic performance were collected. The Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and Internet Addiction Test (IAT) were used to assess the mental health problems. Results: Of 60,268 participants, 36,247 (60.2%) middle and high school students reported that their studies were affected by the COVID-19 pandemic, and 24,864 (41.2%) reported that their academic performance had worsened. The prevalence of depression and anxiety symptoms was 38.4 and 32.7%, respectively. There was a significant association between academic performance change and mental health problems. The logistic regression analysis showed that improved academic performance was a protective factor for depression, and declined academic performance was a risk factor for depression and anxiety. Being COVID-19 infected, family members being infected, with quarantine experience, and with COVID-19-related stigma were risk factors for depression and anxiety. Conclusion: Academic studies and mental health status of middle and high school students in Sichuan, China have been negatively impacted by the COVID-19 pandemic, even after the lifting of COVID-19 restrictions. Students' academic performance, academic concerns, and mental health status should be considered for educational policymakers and institutions to improve students' academic studies and mental well-being.

2.
Front Psychol ; 14: 1118481, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37469892

RESUMO

Introduction: During the COVID-19 pandemic in China, the silent management (Lockdown) policy has caused severe sleep problems for university students. Long-term isolation may further deteriorate sleep quality, and it requires practical interventions. Today in mental and sleep health, interventions based on Buddhist, Taoist and Confucian ethics have been proven effective in reducing cognition and sleep disorders. However, such interventions also have limitations. They tend to focus on peace of mind or some technical means with the main direction of symptom improvement but neglect the mundane activities of daily life. Methods: We conducted an innovative tranquil sitting intervention program based on the Chinese Confucian value of the "tranquility and reverence" method, integrating various intervention techniques traditionally recognized as effective for achieving more lasting mental health and sleep quality. This study aims to assess the effectiveness and feasibility of a tranquil sitting intervention in improving sleep problems in isolated university students. Using a randomized control trial (RCT), the participants in the intervention program (n = 35) practiced the tranquil sitting intervention program for ten weeks. They had their PSQI scores measured at the pre-experimental, post-test, and 1-month follow-up time points and compared to the control group (n = 35). Results: The participants who received the tranquil sitting intervention had significantly better sleep quality than the control group, with moderate to large effect sizes in the middle and late stages. The instructor may challenge the intervention group at the beginning of the tranquil sitting technique. However, the improvement in sleep quality was significant after fully mastering the method. Discussion: The intervention program in this study emphasized the importance of "tranquility" and showed the same sleep improvement as in other traditional interventions. In conclusion, this intervention is a feasible and promising new approach to improving sleep quality among youths.

3.
Front Psychol ; 13: 1013773, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275277

RESUMO

Some studies have concentrated on the adverse effects of unreasonable tasks on work engagement. So far, however, the underlying mechanisms and boundary conditions of the relationship have not been adequately discussed. Based on the cognitive-affective systems theory and the job demands-resources model, this study constructs a chain mediation model in which unreasonable tasks influence work engagement through work alienation and negative affect and explores the moderating role of supervisor support in the model. An analysis of 427 questionnaires from multiple types of organizations shows that: Unreasonable tasks have a negative impact on work engagement; work alienation and negative affect play both separate and chain mediating roles in the negative effect of unreasonable tasks on work engagement, and supervisor support negatively moderates chain mediation by moderating the positive effect of unreasonable tasks on work alienation. This study re-investigates the relationship between unreasonable tasks and work engagement from cognitive, affective, and resource perspectives, which could be a valuable addition to established research and provide suggestions and assistance for management practice.

4.
Eur J Pharm Sci ; 152: 105429, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32561460

RESUMO

Poly (vinyl alcohol), PVA, a commonly used excipient to coat tablets, forms insoluble films in the presence of acids and thermal stress. This may lead to drug products failing to meet dissolution specifications over time. Studies were conducted to understand the effect of acid strength, processing conditions, and storage stress on the mechanism of insoluble film formation using PVA and OpadryⓇ II as model systems. Aqueous cast films, prepared by incorporating hydrochloric acid (HCl) into the coating solutions or exposing pre-cast "as is" films to HCl vapors, were used as surrogates to develop analytical methods. To understand effect of acid and processing on coatings, acidified OpadryⓇ II was spray coated onto inert cores under "wet" or "dry" conditions. Samples stored at 50-60 °C were analyzed for film disintegration to understand physical/chemical changes in the polymer. Rate and extent of insoluble films formation was dependent on the acid concentration and thermal stress. Analysis of the films indicated significant de-acetylation and ether bond formation in insoluble aqueous cast films. In contrast, acidified coated films showed only ether bond formation, which increased on stress, forming insoluble films. The reduction in the time to form insoluble films for "wet" versus "dry" coated films was rationalized by considering effect of coating, drying, and storage on the microstructure of acidified PVA and ether bond propagation. The results highlight the need to develop an in-depth understanding of the design space for PVA coated products and storage conditions in presence of acids.


Assuntos
Excipientes , Álcool de Polivinil , Polímeros , Comprimidos
5.
J Pharm Sci ; 109(2): 1050-1058, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31622601

RESUMO

The effect of vapor sorption on the free volume of drug-polymer spray-dried dispersions (SDDs) was investigated, along with the crystallization propensity of drug molecules in SDDs after exposure to humidity. Subsequently, the correlation of free volume change and relaxation time with drug recrystallization was examined. Four polymers, including polyvinylpyrrolidone, polyvinylpyrrolidone vinyl acetate copolymer, hydroxypropyl cellulose, and hydroxypropyl methylcellulose acetate succinate, and 2 drugs (indomethacin and ketoconazole) were selected for preparing SDDs. Free volume data of the exposed SDDs were obtained with positron annihilation lifetime spectroscopy, while the relaxation time was measured using a TA rheometer. Additionally, the crystallization propensity of active pharmaceutical ingredients (APIs) in the exposed SDDs was assessed using both polarized light microscopy and powder X-ray diffraction, followed by relating API crystallization inclination with expansion of holes and relaxation time. Finally, Cohen and Turnbull molecular transport model, along with its extensions by Vrentas and Duda, was qualitatively utilized for interpreting the recrystallization propensity of API molecules. In conclusion, API recrystallization is closely related to free volume change upon moisture sorption and relaxation time, but system dependent; overall, drug-hydroxypropyl methylcellulose acetate succinate SDDs appear physically stable against recrystallization due to less increase in free volume.


Assuntos
Cetoconazol , Cristalização , Estabilidade de Medicamentos , Pós , Solubilidade , Difração de Raios X
6.
J Pharm Sci ; 107(4): 1204-1208, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29233726

RESUMO

Despite the increasing importance of mini-tablet for its advantages as pediatric formulations and in modified-release applications, its popularity is limited due to the lack of formulation and processing knowledge in developing such dosage forms. In this study, common grades of microcrystalline cellulose and roller compacted granules with a range of powder properties were used to evaluate the critical material properties required for the successful manufacturing of 1.7-mm mini-tablets. It was found that blends with small particle size had poor flow properties that did not support consistent die filling and also tended to cause tooling jam and damage. While the granulation process was effective in improving blend flow properties by increasing particle size, it is imperative to avoid very large particles that could also cause inadequate flow by blocking the space within the die. Successful mini-tablet compression could be achieved by removing particles larger than roughly 1/3 of the die diameter or milling the granules using a screen less than 1/3 of the die diameter.


Assuntos
Pós/química , Comprimidos/química , Celulose/química , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Excipientes/química , Tamanho da Partícula , Pressão
7.
AAPS J ; 19(5): 1387-1395, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28608238

RESUMO

In formulation development, certain excipients, even though used in small quantities, can have a significant impact on the processability and performance of the dosage form. In this study, three common disintegrants, croscarmellose sodium (CCS), crospovidone (xPVP), and sodium starch glycolate (SSG) as well as the surfactant sodium lauryl sulfate (SLS) were evaluated for their impact on the processability and performance of a typical dry granulation formulation. Two model compounds, the mechanically brittle and chemically inert acetaminophen and the mechanically ductile carboxylic acid aspirin, were used for the evaluation. It was found that the disintegrants were generally identical in their impact on the processability and little difference was observed in the granulation and compression processes. The exception is that when xPVP was used in the formulation of the brittle acetaminophen, lower compression forces were needed to reach the same tablet hardness, suggesting a binding effect of xPVP for such systems. In general, CCS and xPVP tend to provide slightly better disintegration than SSG. However, in the case of aspirin, a strong hydrogen bonding interaction between the carboxylic acid group of aspirin and the carbonyl group of xPVP was observed, resulting in slower release of the drug after fast disintegration. SLS was found to have a significant impact on the processability due to its lubricating effect, resulting in higher compression forces needed to achieve the target tablet hardness. Due to the higher degree of compression, the disintegration and dissolution of both drugs became slower despite the wetting effect of SLS.


Assuntos
Acetaminofen/química , Aspirina/química , Tensoativos/farmacologia , Carboximetilcelulose Sódica/farmacologia , Química Farmacêutica , Povidona/farmacologia , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos
8.
Pharm Res ; 32(2): 500-15, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25107427

RESUMO

PURPOSE: To investigate the structural effect of polymeric excipients on the behavior of free volume of drug-polymer dispersions in relation to glass transition. METHODS: Two drugs (indomethacin and ketoconazole) were selected to prepare amorphous dispersions with PVP, PVPVA, HPC, and HPMCAS through spray drying. The physical attributes of the dispersions were characterized using SEM and PXRD. The free volume (hole-size) of the dispersions along with drugs and polymers was measured using positron annihilation lifetime spectroscopy (PALS). Their glass transition temperatures (Tgs) were determined using DSC and DMA. FTIR spectra were recorded to identify hydrogen bonding in the dispersions. RESULTS: The chain structural difference-flexible (PVP and PVPVA) vs. inflexible (HPC and HPMCAS)-significantly impacts the free volume and Tgs of the dispersions as well as their deviation from ideality. Relative to Tg, free volume seems to be a better measure of hydrogen bonding interaction for the dispersions of PVP, HPC, and HPMCAS. The free volume of polymers and their dispersions in general appears to be related to their conformations in solution. CONCLUSIONS: Both the backbone chain rigidity of polymers as well as drug-polymer interaction can impact the free volume and glass transition behaviors of the dispersions.


Assuntos
Excipientes/química , Vidro/química , Indometacina/química , Cetoconazol/química , Polímeros/química , Temperatura de Transição , Excipientes/análise , Indometacina/análise , Cetoconazol/análise , Polímeros/análise
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