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1.
Small ; 20(11): e2306299, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37929651

RESUMO

Persistent luminescence (PersL) materials exhibit thermal-favored optical behavior, enabling their unique applications in security night vision signage, in vivo bioimaging, and optical anti-counterfeiting. Therefore, developing efficient and color-tunable PersL materials is significantly crucial in promoting advanced practical use. In this study, hexagonal Zr4+ -doped CsCdCl3 perovskite is synthesized via a hydrothermal reaction with a tunable photoluminescent (PL) behavior through heterovalent substitution. Moreover, the incorporation of Zr4+ ions result in an extra blue emission band, originating from the enhanced excitonic recombination in D3d octahedrons. Furthermore, the afterglow performances of the samples are dramatically improved, along with the noticeable temperature-dependent PersL as well as the thermo-luminescence with tunable color output. Detailed analysis reveals that the unique temperature-dependent PersL and thermo-luminescence color change are attributed to the presence of multiple luminous centers and abundant traps. Overall, this work facilitates the development of optical intelligence platforms and novel thermal distribution probes with the as-developed halides perovskite for its superior explored PersL characteristic.

2.
MAGMA ; 37(1): 39-51, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37715877

RESUMO

OBJECTIVE: To find a possible quantitative relation between activation-induced fast (< 10 s) changes in the γ-aminobutyric acid (GABA) level and the amplitude of a blood oxygen level-dependent contrast (BOLD) response (according to magnetic resonance spectroscopy [MRS] and functional magnetic resonance imaging [fMRI]). MATERIALS AND METHODS: fMRI data and MEGA-PRESS magnetic resonance spectra [echo time (TE)/repetition time (TR) = 68 ms/1500 ms] of an activated area in the visual cortex of 33 subjects were acquired using a 3 T MR scanner. Stimulation was performed by presenting an image of a flickering checkerboard for 3 s, repeated with an interval of 13.5 s. The time course of GABA and creatine (Cr) concentrations and the width and height of resonance lines were obtained with a nominal time resolution of 1.5 s. Changes in the linewidth and height of n-acetylaspartate (NAA) and Cr signals were used to determine the BOLD effect. RESULTS: In response to the activation, the BOLD-corrected GABA + /Cr ratio increased by 5.0% (q = 0.027) and 3.8% (q = 0.048) at 1.6 and 3.1 s, respectively, after the start of the stimulus. Time courses of Cr and NAA signal width and height reached a maximum change at the 6th second (~ 1.2-1.5%, q < 0.05). CONCLUSION: The quick response of the observed GABA concentration to the short stimulus is most likely due to a release of GABA from vesicles followed by its packaging back into vesicles.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Estimulação Luminosa , Encéfalo/diagnóstico por imagem , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico , Creatina , Ácido Glutâmico
3.
Nano Lett ; 23(18): 8753-8760, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37712849

RESUMO

X-ray dose detection plays a critical role in various scientific fields, including chemistry, materials, and medicine. However, the current materials used for this purpose face challenges in both immediate and delayed radiation detections. Here, we present a visual X-ray dosimetry method for multienvironment applications, utilizing NaLuF4 nanocrystals (NCs) that undergo a color change from green to red upon X-ray irradiation. By adjustment of the concentrations of Ho3+, the emission color of the NCs can be tuned thanks to the cross-relaxation effects. Furthermore, X-ray irradiation induces generation of trapping centers in NaLuF4:Ho3+ NCs, endowing the generation of mechanoluminescence (ML) behavior upon mechanical stimulation after X-ray irradiation ceases. The ML intensity shows a linear correlation with the X-ray dose, facilitating the detection of delayed radiation. This breakthrough facilitates X-ray dose inspection in flaw detection, nuclear medicine, customs, and civil protection, thereby enhancing opportunities for radiation monitoring and control.

4.
Opt Lett ; 48(11): 2833-2836, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262222

RESUMO

We present a diode-pumped Yb:YLF laser system generating 100-mJ sub-ps pulses at a 1-kHz repetition rate (100 W average power) by chirped-pulse amplification. The laser consists of a cryogenically cooled 78 K, regenerative, eight-pass booster amplifier seeded by an all-fiber front end. The output pulses are compressed to 980 fs in a single-grating Treacy compressor with a throughput of 89%. The laser will be applied to multi-cycle THz generation and pumping of high average power parametric amplifiers.

5.
J Magn Reson Imaging ; 57(5): 1433-1442, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36053885

RESUMO

BACKGROUND: Mild traumatic brain injury (mTBI) causes a number of molecular and cellular alterations. There is evidence of an imbalance between the main excitatory (glutamate, Glu) and the main inhibitory (gamma-aminobutyric acid [GABA]) neurotransmitters following mTBI. In vivo human GABA-Glu balance studies following mTBI are sparse. PURPOSE: To investigate the effect of acute mTBI on the GABA concentration measured in the posterior cingulate cortex (PCC) of pediatric patients by using the macromolecular (MM)-suppressed GABA J-editing technique. STUDY TYPE: Prospective patient and phantom. PARTICIPANTS: A total of 14 pediatric patients (mean age 16.0 ± 1.7) with acute mTBI (<3 days after trauma; Glasgow Coma Scale 15) and 16 healthy volunteers (mean age 16.9 ± 2.8). Phantom: 524 cm3 sphere containing 10 mM glycine, 10 mM GABA. FIELD STRENGTH/SEQUENCE: A 3 T, MEGA-PRESS pulse sequence. ASSESSMENT: GABA spectra were processed in Gannet software. MM-suppressed GABA editing efficiency was derived from the phantom study. Absolute GABA and glutamate + glutamine (Glx) concentrations were quantified using different types of correction and compared between groups. N-acetyl aspartate (NAA) and choline (Cho) levels relative to tCr were also compared. STATISTICAL TESTS: Shapiro-Wilk test, Mann-Whitney U test, Student t-test, Pearson or Spearman correlations. P < 0.01 was considered statistically significant. RESULTS: The MM-suppressed GABA editing efficiency was 0.63. GABA signal fit error was <16% for all participants. The GABA concentration in the PCC of the mTBI group was significantly different from that in healthy controls: GABA/tCr was higher by 27%, absolute GABA concentration with different types of correction was higher by ≈17%. No significant differences were observed in Glx concentrations (P ≥ 0.32) or in Glx/tCr (P ≥ 0.1), NAA/tCr (P = 0.55), and Cho/tCr levels (P = 0.85). DATA CONCLUSION: We report an increase in the GABA concentration in the PCC region in acute mTBI pediatric patients. This may suggest activation of GABA synthesis and impairment of the GABAergic system after acute mTBI. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 1.


Assuntos
Concussão Encefálica , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Giro do Cíngulo , Estudos Prospectivos , Espectroscopia de Ressonância Magnética/métodos , Ácido Glutâmico , Ácido gama-Aminobutírico , Substâncias Macromoleculares , Receptores de Antígenos de Linfócitos T
6.
Inorg Chem ; 62(20): 7914-7920, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37147772

RESUMO

Scintillator is a key component in X-ray detectors that determine the performance of the devices. Nevertheless, due to the interference of the ambient light sources, scintillators are only operated in a darkroom environment currently. In this study, we designed a Cu+ and Al3+ co-doped ZnS scintillator (ZnS: Cu+, Al3+) that introduces donor-acceptor (D-A) pairs for X-ray detection. The prepared scintillator displayed an extremely high steady-state light yield (53,000 photons per MeV) upon X-ray irradiation, which is 5.3 times higher than that of the commercial Bi4Ge3O12 (BGO) scintillator, making it possible in X-ray detection with the interference of ambient light. Furthermore, the prepared material was employed as a scintillator to construct an indirect X-ray detector, which performed a superior spatial resolution (≈10.0 lp/mm) as well as persistent stability under visible light interference, demonstrating the feasibility of the scintillator in practical applications. Therefore, this research presented a convenient and useful strategy to realize X-ray detection in a non-darkroom environment.

7.
Inorg Chem ; 62(40): 16485-16492, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37738045

RESUMO

The current optical anticounterfeit strategies that rely on multimode luminescence in response to the photon or thermal stimuli have significant importance in the field of anticounterfeiting and information encryption. However, the dependence on light and heat sources might limit their flexibility in practical applications. In this work, Er3+ single-doped CaF2 phosphors that show multistimuli-responsive luminescence have been successfully prepared. The as-obtained CaF2:Er3+ phosphor exhibits green photoluminescence (PL) and color-tunable up-conversation (UC) luminescence from red to green due to the cross-relaxation of Er3+ ions. Additionally, as-obtained CaF2:Er3+ phosphors also display green mechano-luminescence behavior, which is induced by the contact electrification between the CaF2 particles and PDMS polymers, enabling the phosphor to flexibly respond to mechanical stimuli. Moreover, feasible anticounterfeiting schemes with the capability of multistimuli-responsive and flexible decryption have been constructed, further expanding the application of optical materials in the field of advanced anticounterfeiting and information encryption.

8.
Phys Chem Chem Phys ; 25(38): 25985-25992, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37728403

RESUMO

Near-infrared (NIR) luminescent materials have attracted wide research interest due to their unique photophysical properties for designing NIR light-emitting diodes (NIR LEDs). Here, a series of Cr3+-activated NIR-emitting solid solution phosphors, Gd1-xLux(Al1-xScx)3(BO3)4:0.01Cr3+ (GLASB:Cr3+) (x = 0 to 0.5), are successfully synthesized via a cosubstitution approach. The GLASB:Cr3+ phosphors reveal extraordinary optical performance with a desirable high IQE of 93.6%, considerable broadened FWHM (from 128 nm to 196 nm) and redshift of 119 nm (747 → 866 nm) as the amount of [Lu3+-Sc3+] ion doping increases. Moreover, their photoluminescent thermal stability is substantially improved, maintaining 105.7% of the initial integral intensity up to 150 °C, namely zero-thermal-quenching. The NIR pc-LED fabricated using the GLASB:Cr3+ phosphor generates an NIR output power of 46 mW and an electro-optical efficiency of 37% at a 120 mA input current. Finally, the characteristic NIR emission of this phosphor can not only be utilized in the fields of night-vision technology and biometric identification, but also exhibits a perfect match with the absorption of the bacteriochlorophyll (BChl) and light-harvesting protein (LHP) of photosynthetic bacteria (PSB), presenting a high application prospect for improving PSB photosynthesis.

9.
Opt Lett ; 47(7): 1895-1898, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363763

RESUMO

The magneto-optical properties of single-crystal silicon were investigated as a function of wavelength and temperature. A bulk free-space traditional Faraday isolator for the radiation with a wavelength of 1940 nm (magnetic field ∼2.8 Т) was implemented. The negative value of the piezo-optical anisotropy ratio of the used material allowed for the development of a Faraday isolator with compensation of thermally induced depolarization without a reciprocal rotator. The potential of single-crystal silicon as a magneto-optical material for Faraday isolators operating at room as well as at cryogenic temperatures in high-power laser radiation was considered. It was shown that single-crystal silicon is highly promising for the development of Faraday devices, including ones for next-generation laser interferometers aimed at detecting gravitational waves.

10.
Opt Lett ; 47(3): 473-476, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103654

RESUMO

Single-crystal silicon is one of the most promising materials for producing test masses for the new generation of laser interferometers intended for the detection of gravitational waves. We studied the thermally induced depolarization of radiation in single-crystal silicon with [001] orientation at a wavelength of 1940 nm at room temperature. The value of the piezo-optical anisotropy ratio was found to be ξ = -0.63 ± 0.05 for one manufacturer and ξ = 0.62 ± 0.05 for another. The physical reason for the different signs was not established, and the search for this reason will continue. For the single-crystal silicon with the negative piezo-optical anisotropy ratio, the directions of the special orientations [C] and [P] for which thermally induced depolarization and thermal lens astigmatism vanish, respectively, were determined. When ξ is close to -0.5, the special orientations are close to [111], making this orientation preferable to the other traditionally used orientation, [001].

11.
Opt Lett ; 46(15): 3592-3595, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329232

RESUMO

Thermo-optical properties of several (Tb1-xYx)2O3 ceramic samples were investigated in this Letter. The linear absorption and thermal conductivity coefficients, as well as the power dependence of thermally induced phase and polarization distortions of laser radiation, were measured. In addition, the effective thermo-optical constants Peff and Qeff were estimated. Thermo-optical properties of the studied ceramics were compared with those of the widely used terbium gallium garnet. It was shown that the material under consideration is highly promising for Faraday isolators operating at high average power laser radiation.

12.
Magn Reson Med ; 84(6): 2918-2931, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32544309

RESUMO

PURPOSE: To separately measure N-acetyl aspartul glutamate (NAAG), N-acetyl aspartate (NAA), aspartate (Asp), and glutamate (Glu) concentrations in white matter (WM) using J-editing techniques in patients with mild traumatic brain injury (mTBI) in the acute phase. METHODS: Twenty-four patients with closed concussive head injury and 29 healthy volunteers were enrolled in the current study. For extended 1 H MRS examination, patients and controls were equally divided into two subgroups. In subgroup 1 (12 patients/15 controls), NAAG and NAA concentrations were measured in WM separately with MEGA-PRESS (echo time/repetition time [TE/TR] = 140/2000 ms; δONNAA / δOFFNAA = 4.84/4.38 ppm, δONNAAG / δOFFNAAG = 4.61/4.15 ppm). In subgroup 2 (12 patients/14 controls), Asp and Glu concentrations were acquired with MEGA-PRESS (TE/TR = 90/2000 ms; δONAsp / δOFFAsp = 3.89/5.21 ppm) and TE-averaged PRESS (TE from 35 ms to 185 ms with 2.5-ms increments; TR = 2000 ms) pulse sequences, respectively. RESULTS: tNAA and NAAG concentrations were found to be reduced, while NAA concentrations were unchanged, after mild mTBI. Reduced Asp and elevated myo-inositol (mI) concentrations were also found. CONCLUSION: The main finding of the study is that the tNAA signal reduction in WM after mTBI is associated with a decrease in the NAAG concentration rather than a decrease in the NAA concentration, as was thought previously. This finding highlights the importance of separating these signals, at least for WM studies, to avoid misinterpretation of the results. NAAG plays an important role in selectively activating mGluR3 receptors, thus providing neuroprotective and neuroreparative functions immediately after mTBI. NAAG shows potential for the development of new therapeutic strategies for patients with injuries of varying severity.


Assuntos
Ácido Aspártico , Concussão Encefálica , Ácido Aspártico/análogos & derivados , Encéfalo , Concussão Encefálica/diagnóstico por imagem , Criança , Dipeptídeos , Ácido Glutâmico , Humanos
13.
Opt Lett ; 45(24): 6783-6786, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325896

RESUMO

The thermal lens was investigated in CaF2 and Tb3Ga5O12 cubic crystals with [001] crystallographic axes orientation and in magneto-optical glass MOG103 by the method of phase-shifting interferometry. It was demonstrated experimentally that the thermal lens has astigmatism determined by the incident radiation polarization state and by the optical anisotropy parameter ξ. A method of ξ determination by measuring thermal lens astigmatism in cubic crystals with [001] orientation was proposed and verified. It was shown that thermally induced depolarization and the amplitude of phase astigmatism depend on the position of the crystal with [001] orientation in antiphase.

14.
AIDS Care ; 32(sup2): 99-106, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32162527

RESUMO

Half of HIV-positive persons in Russia are on antiretroviral therapy (ART), and only 27% are virally suppressed. A feasibility pilot intervention to mobilize social capital resources for HIV care support was conducted in St. Petersburg. Out-of-care or ART-nonadherent HIV-positive persons (n = 24) attended a five-session intervention to increase access social capital resources (i.e., family, friends, or providers) to mobilize supports for entering care, initiating care, and adhering to ART. HIV care indicators were assessed at baseline, an immediate followup (FU-1), and 6-month followup (FU-2) points. At FU-1, participants more frequently discussed their care experiences with others, verifying the intervention's mechanism of action. Participants increased in scales of medication taking adherence (p = 0.002, FU-1; p = 0.011, FU-2), self-efficacy (p = 0.042; FU-1), and outcome expectancies (p = 0.016, FU-2). Among persons not on ART, HIV Medication Readiness scale scores increased at FU-1 (p = 0.032) but became attenuated at FU-2. Participants tended to more frequently keep care appointments (79%, baseline to 90%, FU-1, p = 0.077); to have undetectable viral load (54%, baseline to 74%, FU-2; p = 0.063); and to have fewer past-month days with delayed or incomplete medication doses (7.8, baseline to 4.2, FU-1; p = 0.084). This novel social capital intervention is promising for improving HIV care-related outcomes and warrants a full-scale evaluation.


Assuntos
Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Adesão à Medicação/psicologia , Autoeficácia , Capital Social , Rede Social , Adulto , Feminino , Infecções por HIV/epidemiologia , Recursos em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Federação Russa/epidemiologia , Apoio Social , Carga Viral
15.
BMC Med Inform Decis Mak ; 20(1): 201, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32831065

RESUMO

BACKGROUND: Methods of data mining and analytics can be efficiently applied in medicine to develop models that use patient-specific data to predict the development of diabetic polyneuropathy. However, there is room for improvement in the accuracy of predictive models. Existing studies of diabetes polyneuropathy considered a limited number of predictors in one study to enable a comparison of efficiency of different machine learning methods with different predictors to find the most efficient one. The purpose of this study is the implementation of machine learning methods for identifying the risk of diabetes polyneuropathy based on structured electronic medical records collected in databases of medical information systems. METHODS: For the purposes of our study, we developed a structured procedure for predictive modelling, which includes data extraction and preprocessing, model adjustment and performance assessment, selection of the best models and interpretation of results. The dataset contained a total number of 238,590 laboratory records. Each record 27 laboratory tests, age, gender and presence of retinopathy or nephropathy). The records included information about 5846 patients with diabetes. Diagnosis served as a source of information about the target class values for classification. RESULTS: It was discovered that inclusion of two expressions, namely "nephropathy" and "retinopathy" allows to increase the performance, achieving up to 79.82% precision, 81.52% recall, 80.64% F1 score, 82.61% accuracy, and 89.88% AUC using the neural network classifier. Additionally, different models showed different results in terms of interpretation significance: random forest confirmed that the most important risk factor for polyneuropathy is the increased neutrophil level, meaning the presence of inflammation in the body. Linear models showed linear dependencies of the presence of polyneuropathy on blood glucose levels, which is confirmed by the clinical interpretation of the importance of blood glucose control. CONCLUSION: Depending on whether one needs to identify pathophysiological mechanisms for one's prospective study or identify early or late predictors, the choice of model will vary. In comparison with the previous studies, our research makes a comprehensive comparison of different decisions using a large and well-structured dataset applied to different decision support tasks.


Assuntos
Neuropatias Diabéticas , Adulto , Idoso , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/epidemiologia , Feminino , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Estudos Prospectivos , Fatores de Risco
16.
J Thromb Thrombolysis ; 48(1): 1-10, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31004312

RESUMO

De-escalation from ticagrelor to clopidogrel in acute coronary syndrome (ACS) may occur for a variety of reasons, including side effects (bleeding and non-bleeding) and costs. This study sought to assess the prevalence of de-escalation from ticagrelor to clopidogrel and the occurrence of adverse clinical outcomes following de-escalation. We conducted a systematic review of clinical trials and real-world studies in ACS patients treated with ticagrelor. Real-world data on the prevalence of de-escalation during hospitalization or at discharge, after hospital discharge, and during the whole study period were included for meta-analysis. Major adverse cardiovascular events (MACE) and bleeding events occurring after de-escalation were also assessed. A total of 12 studies were eligible for meta-analysis of the prevalence of de-escalation. De-escalation from ticagrelor to clopidogrel therapy occurred with a mean prevalence of 19.8% [95% confidence interval (CI) 11.2-28.4%]. De-escalation occurred more frequently in-hospital or at discharge than after hospital discharge (23.7% vs. 15.8%). For assessment of clinical outcomes, a total of six studies were eligible for meta-analysis. Mean rate of MACE for patients with de-escalation was 2.1% (95% CI 1.1-4.1%) and the rate of major bleeding events was 1.3% (95% CI 0.4-4.5%). In conclusion, de-escalation commonly occurs in real-world practice. Although rates of major cardiovascular and bleeding events in this analysis were generally low, the profile of patients suitable for de-escalation, the impact of de-escalation on adverse clinical outcomes and how this is affected by the timing after index ACS warrants further large-scale investigation.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Clopidogrel/uso terapêutico , Ticagrelor/uso terapêutico , Síndrome Coronariana Aguda/complicações , Doenças Cardiovasculares/etiologia , Clopidogrel/efeitos adversos , Hemorragia/etiologia , Hospitalização , Humanos , Alta do Paciente , Prevalência
17.
Nano Lett ; 18(7): 4338-4345, 2018 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-29925235

RESUMO

Two-dimensional (2D) topological insulator is a promising quantum phase for achieving dissipationless transport due to the robustness of the gapless edge states resided in the insulating gap providing realization of the quantum spin Hall effect. Searching for two-dimensional realistic materials that are able to provide the quantum spin Hall effect and possessing the feasibility of their experimental preparation is a growing field. Here we report on the two-dimensional (In, Sb)2[Formula: see text]2[Formula: see text] compound synthesized on Si(111) substrate and its comprehensive experimental and theoretical investigations based on an atomic-scale characterization by using scanning tunneling microscopy and angle-resolved photoelectron spectroscopy as well as ab initio density functional theory calculations identifying the synthesized 2D compound as a suitable system for realization of the quantum spin Hall effect without additional functionalization like chemical adsorption, applying strain, or gating.

18.
AIDS Behav ; 22(3): 791-799, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-27990579

RESUMO

Over 1 million HIV infections have been diagnosed in Russia, and HIV care uptake and viral suppression are very low. 241 HIV-positive individuals in St. Petersburg were enrolled through social networks, provided blood for viral load testing, and completed measures of medication-taking adherence, readiness, and self-efficacy; psychosocial well-being; and substance use. Outcomes included attending an HIV care appointment in the past 6 months, >90% ART adherence, and undetectable viral load. 26% of participants had no recent care appointment, 18% had suboptimal adherence, and 56% had detectable viral load. Alcohol use consistently predicted all adverse health outcomes. Having no recent care visit was additionally associated with being single and greater past-month drug injection frequency. Poor adherence was additionally predicted by lower medication-taking self-efficacy and lower anxiety. Detectable viral load was additionally related to younger age. Comprehensive interventions to improve HIV care in Russia must address substance abuse, anxiety, and medication-taking self-efficacy.


Assuntos
Antirretrovirais/uso terapêutico , Ansiedade/complicações , Continuidade da Assistência ao Paciente , Infecções por HIV/tratamento farmacológico , Adesão à Medicação , Retenção nos Cuidados , Transtornos Relacionados ao Uso de Substâncias/complicações , Carga Viral/efeitos dos fármacos , Adulto , Ansiedade/psicologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Assunção de Riscos , Federação Russa/epidemiologia , Autoeficácia , Transtornos Relacionados ao Uso de Substâncias/psicologia
19.
AIDS Behav ; 20(10): 2433-2443, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26767534

RESUMO

Russia has a large HIV epidemic, but medical care engagement is low. Eighty HIV-positive persons in St. Petersburg completed in-depth interviews to identify barriers and facilitators of medical HIV care engagement. The most commonly-reported barriers involved difficulties accessing care providers, dissatisfaction with the quality of services, and negative attitudes of provider staff. Other barriers included not having illness symptoms, life stresses, low value placed on health, internalized stigma and wanting to hide one's HIV status, fears of learning about one's true health status, and substance abuse. Care facilitators were feeling responsible for one's health and one's family, care-related support from other HIV-positive persons, and the onset of health decline and fear of death. Substance use remission facilitated care engagement, as did good communication from providers and trust in one's doctor. Interventions are needed in Russia to address HIV care infrastructural barriers and integrate HIV, substance abuse, care, and psychosocial services.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Estigma Social , Transtornos Relacionados ao Uso de Substâncias/complicações , Adolescente , Adulto , Continuidade da Assistência ao Paciente/estatística & dados numéricos , Feminino , Infecções por HIV/psicologia , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Nível de Saúde , Humanos , Entrevistas como Assunto , Masculino , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Pesquisa Qualitativa , Federação Russa/epidemiologia , Apoio Social , Transtornos Relacionados ao Uso de Substâncias/psicologia
20.
Stud Health Technol Inform ; 314: 42-46, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38785001

RESUMO

This study focuses on the complex interplay of healthcare, economic factors, and population dynamics, addressing a research gap in regional-level models that integrate diverse features within a temporal framework. Our primary objective is to develop an advanced temporal model for predicting cardiovascular mortality in Russian regions by integrating global and local healthcare features with economic and population dynamics. Utilizing a dataset from the Almazov Center's Department of Mortality Performance Monitoring, covering 94 regions and 752 records from January 1, 2015, to December 31, 2023, our analysis incorporates key parameters such as angioplasty procedures, population morbidity rates, Ischemic Heart Disease (IHD) and Cardiovascular Diseases (CVD) monitoring, and demographic data. Employing XGBoost and a regression model, our methodology ensures the model's robustness and generalizability.


Assuntos
Doenças Cardiovasculares , Previsões , Aprendizado de Máquina , Humanos , Doenças Cardiovasculares/mortalidade , Federação Russa/epidemiologia
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