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1.
Sci Rep ; 14(1): 13866, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879706

RESUMEN

The efficiency of double-junction CIGS/Perovskite-based solar cells has significantly improved through recent research. This study presents a new plasmonic structure for these optical devices, utilizing cluster nanostructures to increase photon absorption between 650 and 1137 nm wavelength ranges. The proposed nanostructure includes two vertically coupled silver nanoparticles embedded at the center of the bottom active layer (CIGS) that absorb most of the incoming light to CIGS within the active layer. The electric field produced by the coupling of the nanoparticles has a superior performance. To analyze the effect of nanoparticle coupling on CIGS/Perovskite solar cell performance, evaluated the short-circuit current density and power conversion efficiency for single and cluster nanostructures with a single nanoparticle in the middle of CIGS. The structures with a single nanoparticle displayed Jsc = 16.89 mA cm-2 and PCE = 31.76%, while the cluster nanostructure represents Jsc = 19 mA cm-2 and PCE = 35.81%. Not only did the use of the cluster nanostructure significantly improve absorption and performance compared to the bare case, but it also exhibited a suitable improvement compared to the single nanoparticle.

2.
J Voice ; 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38679524

RESUMEN

BACKGROUND: Auditory perception plays a crucial role in speech and language development, emphasizing concerns about hearing loss. While cochlear implantation (CI) nearly tackles challenges associated with postlingual hearing loss in adults, the importance of "auditory feedback" and acoustic assessment becomes crucial for evaluating speech disorders and devising effective treatments. This study aims to address the gap in assessing Voice Onset Time (VOT) as an indicator of nuanced variations in the speech of CI users during a continuous speech task. METHOD: Recordings of Persian CAPE-V sentences were obtained from 25 CI users and 25 healthy speakers, with a mean age of 33.2years (SD=11.5, range=18-55years). Ten words, incorporating both voiced and voiceless consonants, were selected from the CAPE-V sentences. VOT measurements for the specified stop consonants at the initial syllables of these chosen words were computed using PRAAT. A comparative analysis between the two age- and gender-matched groups was conducted using an independent sample t test. Subsequently, ANCOVA was employed to examine the influence of demographic factors on VOT values among CI participants. RESULTS: Unvoiced consonant /p/ in /po/, /pɑ/, /pe/, and /pa/ syllables had higher VOT values in the healthy group, while the voiced consonant /d/ in /da/ and /di/ syllables demonstrated higher VOT values in the CI group (P < 0.05). Apart from /po/ and /di/ syllables, no significant impacts of demographic factors on VOT values were observed (P ≥ 0.8). CONCLUSION: Despite the improvement in speech quality after CI, subtle differences persist. The motor theory, which underscores the impact of auditory inputs on temporal coordination, highlights the role of VOT in speech discrimination. Various linguistic factors affect VOT, including articulation position, vowel context, and raised vowels. While CI enhances syllable distinction, challenges in articulation for adults suggest a need for targeted training in rehabilitation programs, ultimately enhancing the quality of life for CI users.

3.
Case Rep Dent ; 2022: 9974197, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36479450

RESUMEN

Teeth replacement is challenging in old patients with severe periodontal disease, limiting prosthetics treatment options. Here, we report a fiber-reinforced composite (FRC) resin bridge using natural tooth pontic in a patient with severe periodontitis. A 60-year-old lady complaining of teeth mobility was diagnosed with severe periodontitis, recession, bone loss, and crowding in the anterior maxillary teeth. Due to a hopeless periodontal prognosis, lateral incisors were extracted and sectioned using a cylindrical diamond bur. The pulp chamber was debrided and filled with self-adhesive flowable composite resin. After three weeks, the pontics were fixed in proximal contact areas, and the FRC bridge was fabricated directly using the resin fiber strip followed by occlusion adjustment, finishing, and polishing. Esthetic, occlusion, and periodontal status were re-evaluated after six months. Here, FRC using natural pontic could successfully reconstruct a natural smile, splint the adjacent teeth, eliminate crowding, and provide stable occlusion. Therefore, this method may be considered for similar cases.

4.
J Dent (Shiraz) ; 23(2 Suppl): 361-368, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36588969

RESUMEN

Statement of the Problem: Oral lichen planus (OLP) is an important inflammatory disease concerning its tendency to malignancy. The etiopathogenesis of this disease is still unknown. Medical geography uses geographic techniques to study factors related to location that cause uneven distribution of disease. Purpose: This study was conducted to map OLP in patients referred to Shiraz Dental School with medical geography techniques and investigate any possible relationship between the number of dentists and health-centers in different regions of Fars province with the number of referrals. Materials and Method: In this cross-sectional study, we evaluated the records of OLP patients referred to Shiraz Dental School from 2007 to 2018. Age, sex, place of residence, occupation, level of education, location of involvement, duration, and cutaneous involvement were recorded. The number of dentists and healthcare centers was obtained from the statistical records of Fars province. A Geographic Information System was used for the assessment of the spatial distribution of OLP. Ordinary least squares (OLS) and geographically weighted regression (GWR) indices were used for evaluating the relationship between the number of dentists and health centers with the number of referrals. Results: From 1006 records, 457 were studied, from which 71% were female (age range of 41-60). The regression coefficient was 0.937 for the number of dentists in each county compared to OLP referrals indicating a strong relationship. The regression coefficient was 0.983 for the number of health-centers. According to GWR analyses in Shiraz neighboring counties like Marvdasht, Sepidan, and Sarvestan, there is a positive relationship between the number of dentists and OLP patients. Conclusion: The results revealed that dentists and health care centers had a good cognition of referring patients with OLP (as a premalignant lesion) for definite diagnosis in Fars counties. But both groups need more education in this matter. Moreover, referrals from settlements near Shiraz were more common because of their easier access.

5.
J Voice ; 2021 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-34857450

RESUMEN

OBJECTIVE: In standardized connected speech samples, cepstral peak prominence (CPP) and smoothed CPP (CPPS) have been described as accurate parameters to evaluate voice quality. Lack of normal auditory feedback in post-lingually deaf CI users might influence tuning the acoustic parameters in speech production. Based on shreds of evidence, normal hearing results in suitable vocal control through the sensory-motor linkage. The main aim of the present study was to compare the cepstral values between the Iranian cochlear implant group and normal peers. METHOD: Persian CAPE-V sentences were recorded from 30 CI users and 30 healthy speakers (mean age=36.7 years, SD=13.5, range=18-60 years). Thirteen /a/vowels were extracted manually from syllables. Each subject phonated sustained /a/vowel for 5 seconds. PRAAT was used to calculate CPP and CPPS. To compare two age- and gender-matched groups, the independent sample t-test was applied. Then, ANCOVA was used to assess the impact of demographic factors on cepstral scores in CI participants. RESULTS: Significant differences between the CI group and normal peers were discovered based on CPP and CPPS in both tasks (reading sentences and sustained vowel) (P < 0.05). Overall, CI users showed higher cepstral values. The implanted ear and prosthesis model had no significant impact on both CPP and CPPS (P ≥ 0.8). CONCLUSION: Higher CPP and CPPS values in the CI users might be due to increased phonatory instability and spectral noise, with the possibility of decreased vocal control and its quality. The outcome suggests that CI group uses a different voice control strategy. These findings should be kept in mind for intervention methods, especially by assessing vocal characteristics and considering the voice quality in adult CI users.

6.
Biomech Model Mechanobiol ; 20(3): 1087-1100, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33646442

RESUMEN

It is essential to study the viral droplet's uptake in the human respiratory system to better control, prevent, and treat diseases. Micro-droplets can easily pass through ordinary respiratory masks. Therefore, the SARS-COV-2 transmit easily in conversation with a regular mask with 'silent spreaders' in the most physiological way of breathing through the nose, indoor and at rest condition. The results showed that the amount of deposited micro-droplets in the olfactory epithelium area is low. Also, due to receptors and long droplet residence time in this region, the possibility of absorption increases in the cribriform plate. This phenomenon eventually could lead to brain lesion damage and, in some cases, leads to stroke. In all inlet flow rates lower than 30 L/min inlet boundary conditions, the average percentage of viral contamination for upper respiratory tract is always less than 50% and more than 50% for the lungs. At 6L/min and 15L/min flow rates, the average percentage of lung contamination increases to more than 87%, which due to the presence of the Coronavirus receptor in the lungs, the involvement of the lungs increases significantly. This study's other achievements include the inverse relationship between droplets deposition efficiency in some parts of the upper airway, which have the most deformation in the tract. Also, the increased deformities per minute applied to the trachea and nasal cavity, which is 1.5 times more than usual, could lead to chest and head bothers.


Asunto(s)
COVID-19/transmisión , COVID-19/virología , Modelos Biológicos , Sistema Respiratorio/virología , SARS-CoV-2 , Adulto , Microbiología del Aire , Algoritmos , Fenómenos Biomecánicos , Encéfalo/diagnóstico por imagen , COVID-19/diagnóstico por imagen , Simulación por Computador , Transmisión de Enfermedad Infecciosa/estadística & datos numéricos , Humanos , Hidrodinámica , Imagenología Tridimensional , Inhalación , Masculino , Modelos Anatómicos , Nariz/virología , Pandemias , Tamaño de la Partícula , Frecuencia Respiratoria , Sistema Respiratorio/anatomía & histología , Sistema Respiratorio/diagnóstico por imagen , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/patogenicidad , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Tomografía Computarizada por Rayos X
7.
Comput Methods Programs Biomed ; 200: 105843, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33223278

RESUMEN

BACKGROUND AND OBJECTIVE: It is crucial to study the uptake of viral droplets in the human respiratory system to control, prevent, and treat diseases. METHODS: In this study, a well-verified real anatomical model was used; the passage of air in the human upper respiratory system computed using high-quality Computer Tomography (CT) images. Then, the airflow field, along with the coronavirus micro-droplets injection, was examined in this realistic model using the Fluid-Structure Interaction (FSI) method. The Discrete Phase Model (DPM) was used to solve the field, and with the help of it, the accurate assessment of the temporal and spatial motion of the deposition in the virus-impregnated droplets was obtained in vitro in the upper respiratory system. RESULTS: The results show that the amount of deposited micro-droplets in the nasal cavity area is meager at the inhalation only through the oral. However, it has the most residence time in this area. The most and least droplet absorption occurred in the oral cavity and larynx-trachea, respectively. Deposition efficiency is about 100% in 30 L/min flow rate and 10 µm diameter; in other words, no droplet enters the lungs. This study's other achievements include the relatively inverse relationship between droplets deposition efficiency in some parts of the upper airway, which have the most deformation in the tract. CONCLUSIONS: Utilization of a realistic model with accurate and precise computational analysis can end speculation about the deposition zone, accumulation, and the effects of the COVID-19 virus on the upper respiratory tract. On the other hand, recognizing the virus-containing droplet location can ease understanding the areas where the virus can first infect in the upper respiratory tract.


Asunto(s)
COVID-19/transmisión , Transmisión de Enfermedad Infecciosa , Inhalación , Boca , Sistema Respiratorio/microbiología , SARS-CoV-2/patogenicidad , Humanos , Modelos Biológicos
8.
Int J Audiol ; 59(8): 598-605, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32579038

RESUMEN

Objective: Parental views about the outcomes of implantation on the child's quality of life are valuable sources of information for implantation specialists. The aim at this study was to validate the "Parental Perspectives" questionnaire in Persian language.Design: The original questionnaire was translated from English to Persian language; the final Persian version of questionnaire was prepared and evaluated for validity and reliability. The internal consistency of the questionnaire and test-retest reliability were respectively evaluated by Cronbach's alpha and ICC index. Factor analysis was used to determine the construct validity.Study Sample: The participants of this study were 370 parents of CI children.Results: Sampling adequacy for executing of factor analysis was confirmed by the results of Kaiser-Meyer-Olkin (=0.84) and Bartlett test (p < .05). Three factors were extracted from exploratory factor analysis. Confirmatory factor analysis confirmed the accuracy of the three-dimensional structures. Principal component analysis revealed the structural validity of three factors. Correlation between questionnaire items was good (r = 0.76). Reliability coefficient was calculated as 0.93.Conclusions: The Persian version of the questionnaire has good validity and reliability and can be used to examine the perspectives of the parents about CI.


Asunto(s)
Implantes Cocleares/psicología , Corrección de Deficiencia Auditiva/psicología , Sordera/rehabilitación , Evaluación de la Discapacidad , Encuestas y Cuestionarios/normas , Adolescente , Niño , Corrección de Deficiencia Auditiva/métodos , Sordera/psicología , Análisis Factorial , Femenino , Humanos , Irán , Lenguaje , Masculino , Padres/psicología , Psicometría , Reproducibilidad de los Resultados , Traducciones , Resultado del Tratamiento
9.
Biomed Pharmacother ; 97: 1086-1095, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29136945

RESUMEN

Cholestasis is the stoppage of bile flow which could lead to serious clinical complications if not managed. Cytotoxic bile acids are involved in the pathogenesis of liver injury during cholestasis. There are no promising pharmacological interventions against cholestasis and its associated complications. This study examined the impact of glycine supplementation on liver mitochondria as a major target of bile acids-induced toxicity during cholestasis. Mice underwent BDL operation and received glycine (0.25% and 1% w:v in drinking water). Blood and liver samples were collected at scheduled time intervals (3, 7, and 14 days after BDL surgery). Plasma biomarkers of liver injury, along with markers of oxidative stress in the liver tissue were evaluated. Furthermore, liver mitochondria were isolated, and several mitochondrial indices were assessed. BDL-induced cholestasis was evident in mice as a significant elevation in plasma biomarkers of liver injury. Markers of oxidative stress were significantly increased in the liver of BDL animals. Liver injury was histopathologically evident by tissue necrosis, bile duct proliferation, hydropic changes, inflammation, and fibrosis. Furthermore, high level of reactive oxygen species, lipid peroxidation, depleted glutathione reservoirs, and impaired tissue antioxidant capacity were also detected in the liver of cholestatic mice. An assessment of liver mitochondrial function in BDL animals revealed an inhibition of mitochondrial dehydrogenases activity, collapse of mitochondrial membrane potential, mitochondrial swelling, and increase of reactive oxygen species (ROS), and lipid peroxidation (LPO). Furthermore, a significant decrease in mitochondrial ATP was detected in the liver mitochondria isolated from cholestatic animals. Glycine supplementation (0.25% and 1%) decreased mitochondrial swelling, ROS, and LPO. Moreover, glycine treatment improved mitochondrial membrane potential and restored liver mitochondrial ATP. On the other hand, it was found that glycine supplementation attenuated oxidative stress markers in the liver of BDL animals. Moreover, liver histopathological changes and collagen deposition were markedly mitigated by glycine treatment. The mechanisms for the beneficial effects of glycine administration in cholestatic animals might be linked to its ability for preserving cellular redox environment, preventing oxidative stress, and maintaining mitochondrial functionality.


Asunto(s)
Colestasis/tratamiento farmacológico , Glicina/farmacología , Hígado/patología , Mitocondrias Hepáticas/efectos de los fármacos , Animales , Antioxidantes/metabolismo , Ácidos y Sales Biliares/metabolismo , Biomarcadores/sangre , Colestasis/complicaciones , Colestasis/fisiopatología , Colágeno/metabolismo , Modelos Animales de Enfermedad , Glicina/administración & dosificación , Inflamación/tratamiento farmacológico , Inflamación/patología , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Cirrosis Hepática/etiología , Cirrosis Hepática/prevención & control , Masculino , Ratones , Ratones Endogámicos BALB C , Mitocondrias Hepáticas/patología , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Factores de Tiempo
10.
Iran J Reprod Med ; 13(11): 673-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26730241

RESUMEN

BACKGROUND: Azoospermia is the medical condition of a man not having any measurable level of sperm in his semen. Follicle stimulating hormone (FSH) is a member of the glycoprotein hormone family that plays an important role in human reproduction because of its essential role in normal spermatogenesis. Various Single Nucleotide Polymorphisms (SNPs) have been reported within FSH receptor (FSHR) gene that may affect the receptor function. OBJECTIVE: The present study aimed to investigate the correlation between two FSHR SNPs at positions A919G, A2039G, and susceptibility to azoospermia in a group of Iranian azoospermic men. The association between FSH levels within the sera and A919G and A2039G alleles and genotypes were also investigated. MATERIALS AND METHODS: This case control study was performed on 212 men with azoospermia (126 non-obstructive and 86 obstructive) and 200 healthy Iranian men. Two FSHR gene SNPs were genotyped using PCR-RFLP method. The relationship between FSH levels within the sera and A919G and A2039G alleles and genotypes were also investigated. RESULTS: Statistical analysis indicated that at A919G position, AA genotype and A allele were more frequent in obstructive azoospermia cases compared to non-obstructive or normal men (p=0.001). Regarding A2039G polymorphisms, no significant difference was observed between both azoospermia groups and the controls. The mean level of serum FSH was higher in the non-obstructive men compared to the obstructive patients (23.8 versus 13.8, respectively, p= 0.04). CONCLUSION: The results of the present study indicated that the genetic polymorphisms in the FSHR gene might increase the susceptibility to azoospermia in Iranian men.

11.
Arch Gynecol Obstet ; 286(6): 1459-62, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22825692

RESUMEN

PURPOSE: Although the exact genes involved in preeclampsia (PE) are still not fully discovered, an important role for oxidative stress in its pathogenesis is accepted. XRCC1 (MIM: 194360) and XRCC7 (MIM: 600899) play a crucial role in the DNA repair pathways. Functional polymorphisms in XRCC1 (Arg194Trp and Arg399Gln) and XRCC7 (G6721T) may be risk factors for PE. In the present study, the association between the genetic polymorphisms of XRCC1 and XRCC7 and risk of PE is investigated. METHODS: The present case-control study was performed on 151 preeclapmtic patients, and a total of 344 normal pregnant women, as a control group. Control women had no history of pregnancies with PE. RESULTS: Neither polymorphism of Arg194Trp XRCC1 nor polymorphism of G6721T XRCC7 associated with the risk of PE. The Gln/Gln genotype of Arg399Gln XRCC1 polymorphism increased the risk of PE (OR=2.39, 95 % CI: 1.38-4.14, P=0.002). Statistical analysis revealed that the haplotype "194Arg-399Gln" showed higher frequency among PE patients compared to the controls (OR=1.65, 95% CI: 1.23-2.19, P=0.001). CONCLUSIONS: The present results suggest that the 399Gln allele of the XRCC1 is significant risk factor for PE development.


Asunto(s)
Proteína Quinasa Activada por ADN/genética , Proteínas de Unión al ADN/genética , Proteínas Nucleares/genética , Polimorfismo Genético , Preeclampsia/genética , Adulto , Estudios de Casos y Controles , Intervalos de Confianza , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Oportunidad Relativa , Estrés Oxidativo/genética , Embarazo , Factores de Riesgo , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X , Adulto Joven
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