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1.
Biochem Pharmacol ; 221: 116039, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38301966

RESUMEN

Translocator protein (18 kDa) (TSPO) plays an important role in retinal neuroinflammation in the early stage of diabetic retinopathy (DR). Studies have found that a FGF1 variant (FGF1ΔHBS) with reduced proliferative potency exerts excellent anti-inflammatory effects and potential therapeutic value for diabetic complications. In this study, intravitreal injection of FGF1ΔHBS was administrated every week for one month in db/db mice, which are genetically predisposed to develop type 2 diabetes mellitus and early retinopathy. Changes in retinal function and structure in the animal models were detected by electrophysiology (ERG) and optical tomography coherence (OCT). TSPO expression and retinal inflammation were analyzed by immunofluorescence, Western blot and real-time qPCR. In the retina of T2D (db/db) mice, FGF1 was significantly down-regulated while FGFR1 was up-regulated (both p < 0.05). TSPO and retinal inflammatory factors were all up-regulated. TSPO and FGFR1 were mainly co-stained in the inner retina. After FGF1ΔHBS treatment, ERG showed that the total amplitude of dark-adapted b-wave and oscillating potentials (Ops) was significantly improved, and OCT showed that the thickness of the retina around the optical nerve head was significantly preserved in T2D mice (all p < 0.05). The TSPO signal was significantly suppressed by FGF1ΔHBS. The activation of NF-κB p65 and the expression of inflammatory factors such as TNF-α, IL-1ß, IL-6, COX-2, MIP-1α, and iNOS were all significantly down-regulated (all p < 0.05). Collectively, our current data demonstrated that intravitreal FGF1ΔHBS treatment can effectively inhibit retinal inflammation via suppressing TSPO signal and to preserve retinal function and structure in a T2D mouse model.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Ratones , Animales , Factor 1 de Crecimiento de Fibroblastos/metabolismo , Factor 1 de Crecimiento de Fibroblastos/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Retina/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/metabolismo , Modelos Animales de Enfermedad , Proteínas Portadoras/metabolismo
2.
Front Psychiatry ; 14: 1178235, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37575585

RESUMEN

Background: Marital status is a robust sociodemographic predictor of sleep. Having to live apart from spouse may have different implications than those of cohabitants or singles, especially in military personnel. Further research on this group will help provide knowledge in advance and facilitate early targeted interventions. Methods: An online questionnaire study was conducted from July to November 2021. A total of 1,832 male military personnel completed the questionnaire. The marital status was measured by a self-reported single choice question. Pittsburgh sleep quality index (PSQI), Epworth Sleepiness Scale (ESS) and The Dysfunctional Beliefs and Attitudes about sleep scale (DBAS-16) were used to measure sleep-related outcomes. Inverse probability weighting (IPW) was applied to reduce the effects of confounding. Logistic regression was used to analyze the relationship between marital status and sleep and explore the impact of living together or not. Results: After inverse probability weighting, the prevalence of poor sleep quality, sleepiness and dysfunctional beliefs were 16.1, 20.1 and 7.1%, respectively. One-way ANOVA results for the means of both groups were statistically significantly different, except for the sleep latency and sleep disturbance dimensions of PSQI. Participants who were married were more likely to have poor sleep quality (OR: 1.408, 95% CI: [1.10, 1.80]), to have daytime sleepiness (OR: 1.560, 95% CI: [1.27, 1.92]) and to develop dysfunctional beliefs and attitudes (OR: 2.497, 95% CI: [1.65, 3.80]) than those who were unmarried. Further analysis showed that the odds of developing poor sleep quality and DBAS in participants who married but living apart were significantly bigger than those unmarried (OR: 1.548 and 3.991, respectively.), while there were no significant differences in the odds of daytime sleepiness (OR: 0.738, p = 0.050). Age was a protective factor for the development of bad sleep outcomes, while family economic was an independent risk factor. Conclusion: Marital status appear important for sleep quality, daytime sleepiness and sleep beliefs. The effect of living apart or not should be considered separately as an important predictor of sleep.

3.
Mil Psychol ; 35(1): 76-84, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37130562

RESUMEN

Military personnel live in operating environments in which poor sleep is common. In this cross-temporal meta-analysis (CTMA), 100 studies (144 data sets, N = 75,998) were identified to examine changes in sleep quality among Chinese active service personnel from 2003 to 2019. Participants were divided into three groups: the navy, the non-navy, and the unknown service. The Pittsburgh Sleep Quality Index (PSQI) was used as the measure of sleep quality; it contains a global score and seven component scores, with higher scores indicative of poorer sleep. Among all active military personnel, the PSQI global and seven component scores decreased from 2003 to 2019. In examining the results by military type, the PSQI global and seven component scores increased in the navy group. Conversely, both the non-navy and unknown-service groups showed decreased PSQI global scores over time. Similarly, all PSQI component scores decreased over time for both the non-navy and unknown service groups, except for the use of sleeping medication (USM), which increased in the non-navy group. In conclusion, the sleep quality of Chinese active service personnel showed a positive trend. Further research should focus on improving the navy's sleep quality.


Asunto(s)
Personal Militar , Calidad del Sueño , Humanos , Pueblo Asiatico , Pueblos del Este de Asia , Sueño
4.
Sleep Breath ; 27(6): 2499-2507, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37059903

RESUMEN

PURPOSE: This study explored the relationship between naps and memory among habitual nappers in China. METHODS: Medical college students participated and were divided into 30-min, 60-min, and 90-min time-in-bed groups. To evaluate declarative and procedural memory performance, A-B and A-C interfering word pair and interfering finger tapping tasks were employed. RESULTS: Among 60 students, a significant decrease in the correct recall rate in the declarative task after having a nap was found only in the 30-min group (p = 0.005). After learning interference (A-C word pairs), the correct recall rate for the declarative task decreased significantly in all interference tests (ps < 0.001). In the procedural task, the speed of sequence A in the retests increased after having a nap in all three groups (ps < 0.048), with a significant decrease in accuracy only in the 30-min group (p = 0.042). After learning interference (sequence B) in the procedural task, the speed of sequence A increased in the 60-min group after 1 h (p = 0.049), and both the 60-min and 90-min groups showed increased speed after one night (ps < 0.022). No significant improvement in speed was found in the 30-min group (ps > 0.05), and this group showed the lowest accuracy for sequence A (ps < 0.16). CONCLUSION: A habitual nap time-in-bed of 60 or 90 min had better effects on declarative and procedural memory consolidation and better memory resistance against interference in procedural memory.


Asunto(s)
Consolidación de la Memoria , Humanos , Recuerdo Mental , China , Sueño
5.
J Psychiatr Res ; 160: 248-257, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36870234

RESUMEN

Facial expressions provide nonverbal cues that are important for delivering and interpreting human emotions. Previous studies have shown that the ability to interpret facial emotions correctly could be partially impaired in sleep-deprived people. People with insomnia might also suffer from sleep loss, so we assumed that facial expression recognition ability might also be impaired in people with insomnia. Despite a growing body of research exploring insomnia's potential impacts on facial expression recognition, conflicting results have been reported, and no systematic review of this research body has been conducted. In this study, after screening 1100 records identified through database searches, six articles examining insomnia and facial expression recognition ability were included in a quantitative synthesis. The main outcomes were classification accuracy (ACC), reaction time (RT), and intensity rating-the three most studied facial expression processing variables. Subgroup analysis was performed to identify altered perceptions according to the facial expressions of four emotions-happiness, sadness, fear, and anger-used to examine insomnia and emotion recognition. The pooled standard mean differences (SMDs) and corresponding 95% confidence intervals (CIs) demonstrated that facial expression recognition among people with insomnia was less accurate (SMD = -0.30; 95% CI: -0.46, -0.14) and slower (SMD = 0.67; 95% CI: 0.18, -1.15) compared to good sleepers. The classification ACC of fearful expression was lower in the insomnia group (SMD = -0.66; 95% CI: -1.02, -0.30). This meta-analysis was registered using PROSPERO.


Asunto(s)
Reconocimiento Facial , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Emociones , Miedo , Felicidad , Expresión Facial
6.
Int J Psychophysiol ; 184: 1-11, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36481460

RESUMEN

BACKGROUNDS: Depression is the most common mental disorder in the world. Sleep deprivation (SD) is a well-known antidepressant. Several recombination protocols (including medications, bright light treatment [BLT], cognitive-behavioral therapy, sleep phrase advance/sleep phrase delay [SPA/SPD], and repetitive transcranial magnetic stimulation [rTMS]) have been developed to improve and maintain the effect of SD. However, relapse after recovery sleep has been reported, and different recombination protocols result in different outcomes. METHODS: The Embase, Cochrane, PubMed, CBM, Web of Science, and CINAHL databases were searched for clinical trials assessing depression and SD. Three independent reviewers classified forty-three abstracts. The Hamilton Depression Rating Scale was used to assess the outcomes. RESULTS: Compared with existing therapy, patients receiving SD displayed a significant improvement in clinician-rated depressive symptoms (MD -1.48 [95 % CI -2.60, -0.37], p < 0.05). A significant decrease was found in the subgroups of SD plus SPA/SPD (odds ratio 3.90 [95 % CI 1.66, 9.17], p < 0.05), total sleep deprivation[TSD] plus BLT (MD -3.28 [95 % CI -5.06, -1.50], p < 0.05), and partial sleep deprivation[PSD] plus rTMS (MD -7.94 [95 % CI -11.44, -4.45], p < 0.05). No significant differences were observed in the other subgroups. CONCLUSIONS: Adding SD to existing therapies showed a positive outcome in improving depression treatment, which provides evidence for the use of SD in treating depression. Further studies are needed to determine the precise effects of SD plus other interventions.


Asunto(s)
Depresión , Privación de Sueño , Humanos , Privación de Sueño/terapia , Depresión/tratamiento farmacológico , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Antidepresivos
7.
Nat Sci Sleep ; 14: 843-853, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35529049

RESUMEN

Purpose: Previous epidemiological and psychological studies have assessed the effects of napping on individual performance and health. However, these studies did not distinguish between spontaneous and passive napping due to sleep disorders. Therefore, this study aimed to explore the potential motivation for napping among Chinese college students and to assess the relationship between different nap motivations and sleep. Patients and Methods: This cross-sectional study was conducted at a university in Shanghai in March 2021 using convenience sampling. A total of 564 Chinese college students with self-reported napping habits participated in this study. Exploratory factor analysis (EFA) was employed to analyze 34 self-rated motivations for napping to derive a potential structural model of napping motivation. Correlation and multiple linear regression analyses were performed to determine the influence of nap motivation on sleep behavior. Results: Chinese college students mainly take naps to reduce fatigue, usually in the form of frequent and long naps (6.25 ± 1.24 days; 64.62 ± 23.70 min). A structural model of nap motivation named the I-DREAM model was proposed, consisting of six factors: restorative, induced, mindful, appetitive, dysregulative, and exercise naps. There were also sex differences in nap motivation, as women preferred restorative naps and appetitive naps, while men preferred exercise naps (p < 0.01, p < 0.05). Furthermore, there was a significant correlation between nap motivation on nap duration, frequency and nighttime sleep quality (R2 = 2.70-18.9%). Conclusion: The proposed I-DREAM model implies that there are population differences in napping motivation. Different motivations also have different relationships with napping patterns and nighttime sleep. In understanding the relationship between naps and health status, nap motivation may be an extremely important influencing factor.

8.
Front Public Health ; 10: 861923, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35400075

RESUMEN

Nap deprivation is regarded as a sleep loss for habitual nappers. The beneficial effects of napping and moderate-intensity aerobic exercise on the reduction in planning ability following nighttime sleep deprivation have been proven. However, it is still unknown whether it can improve the performance decline caused by daytime nap deprivation in habitual nappers. Seventy-four healthy adults who had a long-term habit of taking naps were assigned to three interventions after receiving nap deprivation: (1) Control group (no intervention); (2) Nap group (15-min sitting naps); (3) Exercise group (15-min aerobic exercise), in which subjective alertness, mood, fatigue, and task performance in objective alertness (Psychomotor Vigilance Task, PVT) and planning ability (the Tower of London Task) were measured. Results showed that nap deprivation negatively influenced some performance on the psychomotor vigilance (i.e., response times and 10% slowest response time) and planning ability (i.e., planning time). And acute moderate-intensity aerobic exercise improved psychomotor alertness (i.e., response times) and planning ability (i.e., execution accuracy, execution time), a 15-min sitting naps only alleviated subjective fatigue, whereas some performance (i.e., response times) deteriorated when no intervention was used. These findings suggested that acute moderate-intensity aerobic exercise has a better restorative effect on the reduced planning ability and objective alertness due to nap deprivation compared to sitting naps.


Asunto(s)
Desempeño Psicomotor , Sedestación , Adulto , Ejercicio Físico , Fatiga , Humanos , Desempeño Psicomotor/fisiología , Sueño/fisiología
9.
BMC Cancer ; 21(1): 842, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34284736

RESUMEN

BACKGROUND: Patients with lung cancer (LC) have a poor quality of life (QoL) and easily suffer from psychological diseases. Previous studies focused less on the relationship between genetic factors and QoL, depression, and anxiety status in LC patients. The current study is intended to explore the relationship between SNPs and haplotypes of ERCC1 and ERCC2 and the QoL, depression and anxiety status of patients with LC. METHODS: QoL, depression and anxiety status were assessed in 291 LC patients using the European Organization for Research and Treatment of Cancer (EORTC) Core Quality of Life Questionnaire (QLQ-C30), EORTC Quality of Life Questionnaire-Lung Cancer 13 (QLQ-LC13), SDS and SAS. Nine tag SNPs of ERCC1 and ERCC2 were detected using an improved multiplex ligation detection reaction (iMLDR) technique. Haplotype analysis was conducted using the software Haploview 4.2. The association between SNPs or haplotypes and QoL or depression or anxiety in LC patients was analyzed by regression analysis. RESULTS: ERCC1 rs11615 was associated with emotional functioning (P = 0.027), and ERCC1 rs3212986 was associated with anxiety scores (P = 0.018). ERCC1 rs762562-rs3212986 haplotype was associated with cognitive function (P = 0.029), somatic function (P = 0.014) and dysphagia (OR = 3.32, P = 0.044). Patients with ERCC1 rs3212986-rs11615 AG haplotype had worse cognitive function (adjusted Beta = - 5.42) and somatic function (adjusted Beta = - 6.55) and had severer symptoms of loss of appetite (adjusted OR = 1.67) and dysphagia (adjusted OR = 4.43) (All adjusted P < 0.05). ERCC2 rs13181-rs3916874-rs238416 haplotype was associated with emotional functioning (P = 0.035), pain at other sites (OR 1.88, P = 0.014), chest pain (OR 0.42, P = 0.02), dysphagia (OR 2.82, P = 0.048), and anxiety status (OR 0.23, P = 0.009). CONCLUSION: After adjustment for environmental factors, SNPs and haplotypes of ERCC1 and ERCC2 were associated with different domains of QoL, depression and anxiety in LC patients.


Asunto(s)
Ansiedad/genética , Proteínas de Unión al ADN/genética , Depresión/genética , Endonucleasas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/psicología , Proteína de la Xerodermia Pigmentosa del Grupo D/genética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Polimorfismo de Nucleótido Simple , Calidad de Vida , Adulto Joven
10.
Front Psychiatry ; 12: 696200, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34322041

RESUMEN

Objective: To investigate the prevalence of sleep quality and post-traumatic stress disorder (PTSD) symptoms of healthcare workers (HCWs) and identify the determinants for PTSD symptoms among HCWs in high-risk and low-risk areas during the COVID-19 outbreak in China. Methods: The Pittsburgh Sleep Quality Index and the Impact of Event Scale were used to assess sleep quality and symptoms of PTSD of 421 Chinese HCWs, respectively, from January 30 to March 2, 2020. The influencing factors of PTSD symptoms were identified by univariate analysis and multiple regression. Results: The incidence of HCWs getting PTSD symptoms were 13.2%. HCWs from high-risk areas had significantly poorer sleep quality (p < 0.001). Poor sleep quality was the risk factor of PTSD symptoms for HCWs from high-risk (p = 0.018) and low-risk areas (p < 0.001). Furthermore, non-medical staff were found to be the risk factor for PTSD symptoms only in low-risk areas. Discussion: HCWs in Hubei had poorer sleep quality. Non-medical HCWs from low-risk areas were associated with more severe PTSD symptoms. Mental health programs should be considered for HCWs, especially those who are often overlooked.

11.
BMC Cancer ; 21(1): 739, 2021 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-34176477

RESUMEN

BACKGROUND: The health burden of breast cancer is rising in China. The effect of informed diagnosis on long-term survival is not fully understood. This retrospective cohort study aims to explore the association between early informed diagnosis and survival time in breast cancer patients. METHODS: A total of 12,327 breast cancer patients were enrolled between October 2002 and December 2016. Potential factors, including knowing the cancer diagnosis status, sex, age, clinical stage, surgery history, grade of reporting hospital and diagnostic year were, analyzed. We followed up all participants every 6 months until June 2017. Propensity score matching (PSM) was used to balance the clinicopathologic characteristics between patients who knew their diagnosis and those who did not. RESULTS: By June 2017, 18.04% of the participants died of breast cancer. Before PSM, both the 3-year and 5-year survival rates of patients who knew their cancer diagnosis were longer (P < 0.001). After PSM, the above conclusion was still established. By stratified analysis, except for the subgroups of male patients and stage III patients, patients who knew their diagnosis showed a better prognosis in all the other subgroups (P < 0.05). Cox regression analysis showed that knowing a cancer diagnosis was an independent risk factor for survival in breast cancer patients (P < 0.001). CONCLUSIONS: Being aware of their cancer diagnosis plays a protective role in extending the survival time of breast cancer patients, which suggests that medical staff and patients' families should disclose the cancer diagnosis to patients in a timely manner. Further prospective studies need to be made to validate our findings.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia
12.
PLoS One ; 16(5): e0250779, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33956821

RESUMEN

BACKGROUND: Many reviews and meta-analyses had been conducted to investigate risk factors for sleep disorders in the general population. However, no similar research has been performed in the military population though insomnia and sleep-disordered breathing are quite prevalent in that population. OBJECTIVES: To investigate risk factors for insomnia and sleep-disordered breathing in military personnel. METHODS: A systematic literature search was performed from inception to March 2021 and 6496 records were produced. Two authors independently screened records for eligibility. Results were presented as odds ratios, and a random-effect model was used to pool results. Data analysis was performed respectively according to military personnel type (i.e., veteran, active-duty personnel). Risk factors were sorted into three categories: sociodemographic, army-specific, and comorbidity. This meta-analysis was registered in PROSPERO before data analysis (registration No: CRD42020221696). RESULTS: Twenty-seven articles were finally included in the quantitative analysis. For sleep-disordered breathing in active-duty personnel, four sociodemographic (i.e., overweight/obesity, higher body mass index, male gender, >35 years old) and one comorbidity (i.e., depression) risk factors were identified. For insomnia in active-duty personnel, four sociodemographic (i.e., aging, alcohol dependence, white race, and female gender), two army-specific (i.e., deployment experience, combat experience), and four comorbidity (i.e., depression, post-traumatic stress disorder, traumatic brain injury, and anxiety) risk factors were identified. For insomnia in veterans, one army-specific (i.e., combat experience) and one comorbidity (i.e., post-traumatic stress disorder) risk factor was identified. CONCLUSIONS: Several risk factors were identified for insomnia and sleep-disordered breathing in the current meta-analysis. Risk factors for veterans and active-duty personnel were partially different. Research on sleep breathing disorders remains limited, and more convincing evidence would be obtained with more relevant studies in the future.


Asunto(s)
Personal Militar/estadística & datos numéricos , Síndromes de la Apnea del Sueño/epidemiología , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Humanos , Factores de Riesgo
13.
Chem Res Toxicol ; 25(6): 1265-70, 2012 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-22587431

RESUMEN

As graphene becomes one of the most exciting candidates for multifunctional biomedical applications, contact between eyes and graphene-based materials is inevitable. On the other hand, eyes, as a special organ in the human body, have unique advantages to be used for testing new biomedical research and development, such as drug delivery. Intraocular biocompatible studies on graphene-related materials are thus essential. Here, we report our recent studies on intraocular biocompatibility and cytotoxicity of graphene oxide (GO) both in vitro and in vivo. The successful preparation of GO nanosheets was confirmed using atomic force microscopy, contact angle analyzer, Fourier transform infrared spectroscopy, and Raman spectroscopy. The influence of GO on human retinal pigment epithelium (RPE) cells in terms of the cell morphology, viability, membrane integrity, and apoptosis was investigated using various techniques, including optical micrography, cell counting kit-8 (CCK-8) assay, lactate dehydrogenase (LDH) assay, and apoptosis assay. The addition of GO had little influence on cell morphology, but the change was visible after long-time culturing. RPE cells showed higher than 60% cell viability by CCK-8 assay in GO solutions and less than 8% LDH release, although a small amount of apoptosis (1.5%) was observed. In vitro results suggested good biocompatibility of GO to RPE cells with slight adverse influence, on the cell viability and morphology in long-time periods, along with aggregation of GO. Thus, some further studies are needed to clarify the cytotoxicity mechanism of GO. GO intravitreally injected eyes showed few changes in eyeball appearance, intraocular pressure (IOP), eyesight, and histological photos. Our results suggested that GO did not cause any significant toxicity to the cell growth and proliferation. Intravitreal injection of GO into rabbits' eyes did not lead to much change in the eyeball appearance, IOP, electroretinogram, and histological examination.


Asunto(s)
Ojo/efectos de los fármacos , Ojo/fisiopatología , Grafito/toxicidad , Óxidos/toxicidad , Animales , Apoptosis/efectos de los fármacos , Materiales Biocompatibles , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Electrorretinografía , Ojo/patología , Grafito/administración & dosificación , Grafito/química , Humanos , Óxidos/administración & dosificación , Óxidos/química , Conejos , Relación Estructura-Actividad
14.
Phys Rev Lett ; 98(18): 183901, 2007 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-17501575

RESUMEN

Transition of surface-plasmon resonance from out-of-plane photonic crystal effect is observed in a semiconductor array of subwavelength holes by optical pump-terahertz probe measurements. The dielectric properties of the photoexcited array are essentially altered by the intense optical excitation due to photogenerated free carriers. As a result, the array becomes metallic and favors the coupling and propagation of surface plasmons. The photoinduced resonant extremes agree well with the Fano model.

15.
Opt Lett ; 31(7): 978-80, 2006 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-16599230

RESUMEN

Terahertz (THz) wave generation and detection from a (110)-oriented CdTe crystal via optical rectification and electro-optic sampling has been performed with laser wavelengths ranging from 710 to 970 nm. Three optical rectification regimes are studied with various excitation wavelengths: a resonance-enhanced regime above the bandgap, a highly phase-mismatched regime near the band gap, and a semi-phase-matched regime. A CdTe crystal generates more THz power than a ZnTe crystal at 970 nm.

16.
Opt Lett ; 29(17): 2082-4, 2004 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-15455787

RESUMEN

We report the design and testing of a circular involute stage for high-repetition-rate (hundreds of hertz), fine temporal resolution (better than 10 fs), and long delay range (as great as nanoseconds) time-resolved optical experiments. This stage uses a reflector with the involute profile of a circle as well as a pair of optical mirrors mounted upon a rotating plate to guide the optical beam, following the tangent of the circle. This circular involute stage provides unprecedented performance for optical interference, high-resolution terahertz time-domain spectroscopy, and general optical pump-probe experiments.

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