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Age-related impairments in value representations and updating during decision-making and reward-based learning are often related to age-related attenuation in the catecholamine system such as dopamine (DA) and norepinephrine (NE). However, it is unclear to what extent age-related declines in NE functioning in humans affect reward-based decision-making. We conducted a probabilistic decision-making task and applied a Q-learning model to investigate participants' anticipatory values and value sensitivities. Task-related pupil dilations and locus coeruleus (LC) magnetic resonance imaging (MRI) contrast, which served as a potential window of the LC-NE functions, were assessed in younger and older adults. Results showed that in both choice and feedback phases, younger adults' (N = 42, 22 males) pupil dilations negatively correlated with anticipatory values, indicating uncertainty about outcome probabilities. Uncertainty-evoked pupil dilations in older adults (N = 41, 27 males) were smaller, indicating age-related impairments in value estimation and updating. In both age groups, participants who showed a larger uncertainty-evoked pupil dilation exhibited a higher value sensitivity as reflected in the ß parameter of the reinforcement Q-learning model. Furthermore, older adults (N = 34, 29 males) showed a lower LC-MRI contrast than younger adults (N = 25, 15 males). The LC-MRI contrast positively correlated with value sensitivity only in older but not in younger adults. These findings suggest that task-related pupillary responses can reflect age-related deficits in value estimation and updating during reward-based decision-making. Our evidence with the LC-MRI contrast further showed the age-related decline of the LC structure in modulating value representations during reward-based learning.SIGNIFICANCE STATEMENT Age-related impairments in value representation and updating during reward-based learning are associated with declines in the catecholamine modulation with age. However, it is unclear how age-related declines in the LC-NE system may affect reward-based learning. Here, we show that compared with younger adults, older adults exhibited reduced uncertainty-induced pupil dilations, suggesting age-related deficits in value estimation and updating. Older adults showed a lower structural MRI of the LC contrast than younger adults, indicating age-related degeneration of the LC structure. The association between the LC-MRI contrast and value sensitivity was only observed in older adults. Our findings may demonstrate a pioneering model to unravel the role of the LC-NE system in reward-based learning in aging.
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Locus Coeruleus , Recompensa , Masculino , Humanos , Anciano , Locus Coeruleus/diagnóstico por imagen , Locus Coeruleus/fisiología , Aprendizaje , Refuerzo en Psicología , CatecolaminasRESUMEN
INTRODUCTION: Personal recovery is a complex construct frequently used as outcome measure in people with schizophrenia spectrum disorders. This study examined potential predictors of personal recovery using the two most common assessment tools for people with schizophrenia spectrum disorders living in the community: the Chinese version of the Questionnaire about the Process of Recovery and the Chinese version of the Recovery Assessment Scale. METHODS: Ninety-one individuals (57 women) diagnosed with schizophrenia spectrum disorders participated in the study (mean age: 47.41 ± 9.41 years). All participants lived in the community and received community psychiatric services. The participants were evaluated via interviews, questionnaires and standardized assessments. Potential predictors included four domains: personal, disease-related, functional and social. Stepwise multiple linear regression was used to analyse the potential predictors of the recovery and recovery assessment scale. RESULTS: Resilience and social support were the only significant predictors of the Chinese versions of the Questionnaire about the Process of Recovery and Chinese version of the Recovery Assessment Scale. The primary predictor of the Chinese version of the Questionnaire about the Process of Recovery was social support from family and institutional staff. Conversely, resilience was the major predictor of the Chinese version of the Recovery Assessment Scale. DISCUSSION: For people with schizophrenia spectrum disorders living in the community, social support and resilience significantly predicted personal recovery. Age, educational level, disease-related and functional factors were not significant predictors of personal recovery. Therefore, it is important to develop successful personal recovery-oriented practices that enhance resilience and promote social support.
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Esquizofrenia , Humanos , Femenino , Adulto , Persona de Mediana Edad , Esquizofrenia/terapia , Encuestas y Cuestionarios , Evaluación de Resultado en la Atención de SaludRESUMEN
BACKGROUND: Adults with chronic kidney disease (CKD) are hospitalized more frequently than those without CKD, but the magnitude of this excess morbidity and the factors associated with hospitalizations are not well known. METHODS AND FINDINGS: Data from 3,939 participants enrolled in the Chronic Renal Insufficiency Cohort (CRIC) Study between 2003 and 2008 at 7 clinical centers in the United States were used to estimate primary causes of hospitalizations, hospitalization rates, and baseline participant factors associated with all-cause, cardiovascular, and non-cardiovascular hospitalizations during a median follow up of 9.6 years. Multivariable-adjusted Poisson regression was used to identify factors associated with hospitalization rates, including demographics, blood pressure, estimated glomerular filtration rate (eGFR), and proteinuria. Hospitalization rates in CRIC were compared with rates in the Nationwide Inpatient Sample (NIS) from 2012. Of the 3,939 CRIC participants, 45.1% were female, and 41.9% identified as non-Hispanic black, with a mean age of 57.7 years, and the mean eGFR is 44.9 ml/min/1.73m2. CRIC participants had an unadjusted overall hospitalization rate of 35.0 per 100 person-years (PY) [95% CI: 34.3 to 35.6] and 11.1 per 100 PY [95% CI: 10.8 to 11.5] for cardiovascular-related causes. All-cause, non-cardiovascular, and cardiovascular hospitalizations were associated with older age (≥65 versus 45 to 64 years), more proteinuria (≥150 to <500 versus <150 mg/g), higher systolic blood pressure (≥140 versus 120 to <130 mmHg), diabetes (versus no diabetes), and lower eGFR (<60 versus ≥60 ml/min/1.73m2). Non-Hispanic black (versus non-Hispanic white) race/ethnicity was associated with higher risk for cardiovascular hospitalization [rate ratio (RR) 1.25, 95% CI: 1.16 to 1.35, p-value < 0.001], while risk among females was lower [RR 0.89, 95% CI: 0.83 to 0.96, p-value = 0.002]. Rates of cardiovascular hospitalizations were higher among those with ≥500 mg/g of proteinuria irrespective of eGFR. The most common causes of hospitalization were related to cardiovascular (31.8%), genitourinary (8.7%), digestive (8.3%), endocrine, nutritional or metabolic (8.3%), and respiratory (6.7%) causes. Hospitalization rates were higher in CRIC than the NIS, except for non-cardiovascular hospitalizations among individuals aged >65 years. Limitations of the study include possible misclassification by diagnostic codes, residual confounding, and potential bias from healthy volunteer effect due to its observational nature. CONCLUSIONS: In this study, we observed that adults with CKD had a higher hospitalization rate than the general population that is hospitalized, and even moderate reductions in kidney function were associated with elevated rates of hospitalization. Causes of hospitalization were predominantly related to cardiovascular disease, but other causes contributed, particularly, genitourinary, digestive, and endocrine, nutritional, and metabolic illnesses. High levels of proteinuria were observed to have the largest association with hospitalizations across a wide range of kidney function levels.
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Tasa de Filtración Glomerular , Hospitalización/tendencias , Riñón/fisiopatología , Insuficiencia Renal Crónica/epidemiología , Adulto , Anciano , Femenino , Humanos , Pacientes Internos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/terapia , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Estados Unidos/epidemiología , Adulto JovenRESUMEN
RATIONALE & OBJECTIVE: Safe analgesic choices are limited in chronic kidney disease (CKD). We conducted a comparative analysis of harm from opioids versus nonsteroidal anti-inflammatory drugs (NSAIDs) in CKD. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 3,939 patients with CKD in the Chronic Renal Insufficiency Cohort (CRIC) Study. EXPOSURES: 30-day analgesic use reported at annual visits. OUTCOMES: A composite outcome of 50% glomerular filtration rate reduction and kidney failure requiring kidney replacement therapy (KRT), as well as the outcomes of kidney failure requiring KRT, hospitalization, and pre-kidney failure death. ANALYTICAL APPROACH: Marginal structural models with time-updated exposures. RESULTS: Participants were followed up for a median of 6.84 years, with 391 (9.9%) and 612 (15.5%) reporting baseline opioid and NSAID use, respectively. Time-updated opioid use was associated with the kidney disease composite outcome, kidney failure with KRT, death (HRs of 1.4 [95% CI, 1.2-1.7], 1.4 [95% CI, 1.1-1.7], and 1.5 [95% CI, 1.2-2.0], respectively), and hospitalization (rate ratio [RR], 1.7; 95% CI, 1.6-1.9) versus opioid nonusers. Similar results were found in an analysis restricted to a subcohort of participants reporting ever using other (nonopioid and non-NSAID) analgesics or tramadol. Time-updated NSAID use was associated with increased risk for the kidney disease composite (HR, 1.2; 95% CI, 1.0-1.5) and hospitalization (RR, 1.1; 95% CI, 1.0-1.3); however, these associations were not significant in the subcohort. The association of NSAID use with the kidney disease composite outcome varied by race, with a significant risk in blacks (HR, 1.3; 95% CI, 1.0-1.7). NSAID use was associated with lower risk for kidney failure with KRT in women and individuals with glomerular filtration rate<45mL/min/1.73m2 (HRs of 0.63 [95% CI, 0.45-0.88] and 0.77 [95% CI, 0.59-0.99], respectively). LIMITATIONS: Limited periods of recall of analgesic use and potential confounding by indication. CONCLUSIONS: Opioid use had a stronger association with adverse events than NSAIDs, with the latter's association with kidney disease outcomes limited to specific subgroups, notably those of black race.
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Analgésicos Opioides/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Hospitalización/estadística & datos numéricos , Fallo Renal Crónico/epidemiología , Mortalidad , Dolor/tratamiento farmacológico , Insuficiencia Renal Crónica/metabolismo , Adulto , Negro o Afroamericano , Anciano , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Tasa de Filtración Glomerular , Humanos , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Dolor/complicaciones , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Pirimidinas , Pirroles , Calidad de Vida , Insuficiencia Renal Crónica/complicaciones , Terapia de Reemplazo Renal/estadística & datos numéricos , Población Blanca , Adulto JovenRESUMEN
RATIONALE & OBJECTIVE: Abnormal cardiac structure and function are common in chronic kidney disease (CKD) and end-stage renal disease (ESRD) and linked with mortality and heart failure. We examined changes in echocardiographic measures during the transition from CKD to ESRD and their associations with post-ESRD mortality. STUDY DESIGN: Prospective study. SETTING & PARTICIPANTS: We studied 417 participants with CKD in the Chronic Renal Insufficiency Cohort (CRIC) who had research echocardiograms during CKD and ESRD. PREDICTOR: We measured change in left ventricular mass index, left ventricular ejection fraction (LVEF), diastolic relaxation (normal, mildly abnormal, and moderately/severely abnormal), left ventricular end-systolic (LVESV), end-diastolic (LVEDV) volume, and left atrial volume from CKD to ESRD. OUTCOMES: All-cause mortality after dialysis therapy initiation. ANALYTICAL APPROACH: Cox proportional hazard models were used to test the association of change in each echocardiographic measure with postdialysis mortality. RESULTS: Over a mean of 2.9 years between pre- and postdialysis echocardiograms, there was worsening of mean LVEF (52.5% to 48.6%; P<0.001) and LVESV (18.6 to 20.2mL/m2.7; P<0.001). During this time, there was improvement in left ventricular mass index (60.4 to 58.4g/m2.7; P=0.005) and diastolic relaxation (11.11% to 4.94% with moderately/severely abnormal; P=0.02). Changes in left atrial volume (4.09 to 4.15mL/m2; P=0.08) or LVEDV (38.6 to 38.4mL/m2.7; P=0.8) were not significant. Worsening from CKD to ESRD of LVEF (adjusted HR for every 1% decline in LVEF, 1.03; 95% CI, 1.00-1.06) and LVESV (adjusted HR for every 1mL/m2.7 increase, 1.04; 95% CI, 1.02-1.07) were independently associated with greater risk for postdialysis mortality. LIMITATIONS: Some missing or technically inadequate echocardiograms. CONCLUSIONS: In a longitudinal study of patients with CKD who subsequently initiated dialysis therapy, LVEF and LVESV worsened and were significantly associated with greater risk for postdialysis mortality. There may be opportunities for intervention during this transition period to improve outcomes.
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Ecocardiografía/mortalidad , Ecocardiografía/tendencias , Cardiopatías/diagnóstico por imagen , Cardiopatías/mortalidad , Fallo Renal Crónico/diagnóstico por imagen , Fallo Renal Crónico/mortalidad , Anciano , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Cardiopatías/terapia , Humanos , Fallo Renal Crónico/terapia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Estudios Prospectivos , Insuficiencia Renal Crónica/diagnóstico por imagen , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/terapia , Factores de RiesgoRESUMEN
BACKGROUND: Action semantics have been investigated in relation to context violation but remain less examined in relation to the meaning of gestures. In the present study, we examined tool-gesture incongruity by event-related potentials (ERPs) and hypothesized that the component N400, a neural index which has been widely used in both linguistic and action semantic congruence, is significant for conditions of incongruence. METHODS: Twenty participants performed a tool-gesture judgment task, in which they were asked to judge whether the tool-gesture pairs were correct or incorrect, for the purpose of conveying functional expression of the tools. Online electroencephalograms and behavioral performances (the accuracy rate and reaction time) were recorded. RESULTS: The ERP analysis showed a left centro-parieto-temporal N300 effect (220-360 ms) for the correct condition. However, the expected N400 (400-550 ms) could not be differentiated between correct/incorrect conditions. After 700 ms, a prominent late negative complex for the correct condition was also found in the left centro-parieto-temporal area. CONCLUSIONS: The neurophysiological findings indicated that the left centro-parieto-temporal area is the predominant region contributing to neural processing for tool-gesture incongruity in right-handers. The temporal dynamics of tool-gesture incongruity are: (1) firstly enhanced for recognizable tool-gesture using patterns, (2) and require a secondary reanalysis for further examination of the highly complicated visual structures of gestures and tools. The evidence from the tool-gesture incongruity indicated altered brain activities attributable to the N400 in relation to lexical and action semantics. The online interaction between gesture and tool processing provided minimal context violation or anticipation effect, which may explain the missing N400.
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Potenciales Evocados/fisiología , Juicio/fisiología , Lóbulo Parietal/fisiología , Tiempo de Reacción/fisiología , Lóbulo Temporal/fisiología , Adolescente , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Estimulación Luminosa/métodos , Adulto JovenRESUMEN
BACKGROUND: Hematuria is associated with chronic kidney disease (CKD), but has rarely been examined as a risk factor for CKD progression. We explored whether individuals with hematuria had worse outcomes compared to those without hematuria in the CRIC Study. METHODS: Participants were a racially and ethnically diverse group of adults (21 to 74 years), with moderate CKD. Presence of hematuria (positive dipstick) from a single urine sample was the primary predictor. Outcomes included a 50% or greater reduction in eGFR from baseline, ESRD, and death, over a median follow-up of 7.3 years, analyzed using Cox Proportional Hazards models. Net reclassification indices (NRI) and C statistics were calculated to evaluate their predictive performance. RESULTS: Hematuria was observed in 1145 (29%) of a total of 3272 participants at baseline. Individuals with hematuria were more likely to be Hispanic (22% vs. 9.5%, respectively), have diabetes (56% vs. 48%), lower mean eGFR (40.2 vs. 45.3 ml/min/1.73 m2), and higher levels of urinary albumin > 1.0 g/day (36% vs. 10%). In multivariable-adjusted analysis, individuals with hematuria had a greater risk for all outcomes during the first 2 years of follow-up: Halving of eGFR or ESRD (HR Year 1: 1.68, Year 2: 1.36), ESRD (Year 1: 1.71, Year 2: 1.39) and death (Year 1:1.92, Year 2: 1.77), and these associations were attenuated, thereafter. Based on NRIs and C-statistics, no clear improvement in the ability to improve prediction of study outcomes was observed when hematuria was included in multivariable models. CONCLUSION: In a large adult cohort with CKD, hematuria was associated with a significantly higher risk of CKD progression and death in the first 2 years of follow-up but did not improve risk prediction.
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Progresión de la Enfermedad , Hematuria/diagnóstico , Hematuria/mortalidad , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/mortalidad , Adulto , Anciano , Estudios de Cohortes , Femenino , Hematuria/orina , Humanos , Fallo Renal Crónico/orina , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Estudios Prospectivos , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/orina , Factores de RiesgoRESUMEN
BACKGROUND AND PURPOSE: Emerging work has linked menopausal vasomotor symptoms (VMS) to subclinical cardiovascular disease (CVD) among women. However, VMS are dynamic over time. No studies have considered how temporal patterns of VMS may relate to subclinical CVD. We tested how temporal patterns of VMS assessed over 13 years were related to carotid intima media thickness (IMT) among midlife women. METHODS: The Study of Women's Health Across the Nation is a longitudinal cohort study of midlife women. Eight hundred and eleven white, black, Hispanic, and Chinese participants with a well-characterized final menstrual period completed measures of VMS, a blood draw, and physical measures approximately annually for 13 years. Women underwent a carotid artery ultrasound at study visit 12. RESULTS: Four trajectories of VMS were identified by trajectory analysis (consistently high, early-onset, late-onset, persistently low VMS) and tested in relation to carotid indices in linear regression models. Results indicated that women with early-onset VMS had both greater mean IMT (beta, b [standard error, SE]=0.03 [0.01], P=0.03) and greater maximal IMT (b [SE]=0.04 [0.01], P=0.008) than women with consistently low VMS, adjusting for demographics and CVD risk factors. CONCLUSIONS: This is the first study to test trajectories of VMS in relation to subclinical CVD. Women with VMS early in the menopause transition had higher mean IMT and maximal IMT than those with consistently low VMS across the transition. Associations were not accounted for by demographic factors nor by CVD risk factors. Results can signal to women in need of early CVD risk reduction.
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Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Grosor Intima-Media Carotídeo/tendencias , Sistema Vasomotor/patología , Salud de la Mujer/tendencias , Estudios de Cohortes , Femenino , Humanos , Estudios Longitudinales , Menopausia/fisiología , Persona de Mediana Edad , Posmenopausia/fisiología , Estudios Prospectivos , Estados Unidos/epidemiologíaRESUMEN
The contribution of orthographic representations to reading and writing has been intensively investigated in the literature. However, the distinction between neuronal correlates of the orthographic lexicon and the orthographic (graphemic) buffer has rarely been examined in alphabetic languages and never been explored in non-alphabetic languages. To determine whether the neural networks associated with the orthographic lexicon and buffer of logographic materials are comparable to those reported in the literature, the present fMRI experiment manipulated frequency and the stroke number of Chinese characters in the tasks of form judgment and stroke judgment, which emphasized the processing of character recognition and writing, respectively. It was found that the left fusiform gyrus exhibited higher activation when encountering low-frequency than high-frequency characters in both tasks, which suggested this region to be the locus of the orthographic lexicon that represents the knowledge of character forms. On the other hand, the activations in the posterior part of the left middle frontal gyrus and in the left angular gyrus were parametrically modulated by the stroke number of target characters only in the stroke judgment task, which suggested these regions to be the locus of the orthographic buffer that represents the processing of stroke sequence in writing. These results provide the first evidence for the functional and anatomical dissociation between the orthographic lexicon and buffer in reading and writing Chinese characters. They also demonstrate the critical roles of the left fusiform area and the frontoparietal network to the long-term and short-term representations of orthographic knowledge, respectively, across different orthographies.
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Mapeo Encefálico , Encéfalo/fisiología , Lectura , Escritura , Adulto , Pueblo Asiatico , Femenino , Humanos , Lenguaje , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/fisiología , Reconocimiento Visual de Modelos/fisiología , Adulto JovenRESUMEN
A remote heterodyne millimeter-wave (MMW) carrier at 47.7 GHz over fiber synthesized with the master-to-slave injected dual-mode colorless FPLD pair is proposed, which enables the future connection between the wired fiber-optic 64-QAM OFDM-PON at 24 Gb/s with the MMW 4-QAM OFDM wireless network at 2 Gb/s. Both the single- and dual-mode master-to-slave injection-locked colorless FPLD pairs are compared to optimize the proposed 64-QAM OFDM-PON. For the unamplified single-mode master, the slave colorless FPLD successfully performs the 64-QAM OFDM data at 24 Gb/s with EVM, SNR and BER of 8.5%, 21.5 dB and 2.9 × 10(-3), respectively. In contrast, the dual-mode master-to-slave injection-locked colorless FPLD pair with amplified and unfiltered master can transmit 64-QAM OFDM data at 18 Gb/s over 25-km SMF to provide EVM, SNR and BER of 8.2%, 21.8 dB and 2.2 × 10(-3), respectively. For the dual-mode master-to-slave injection-locked colorless FPLD pair, even though the modal dispersion occurred during 25-km SMF transmission makes it sacrifice the usable OFDM bandwidth by only 1 GHz, which guarantees the sufficient encoding bitrate for the optically generated MMW carrier to implement the fusion of MMW wireless LAN and DWDM-PON with cost-effective and compact architecture. As a result, the 47.7-GHz MMW carrier remotely beat from the dual-mode master-to-slave injection-locked colorless FPLD pair exhibits an extremely narrow bandwidth of only 0.48 MHz. After frequency down-conversion operation, the 47.7-GHz MMW carrier successfully delivers 4-QAM OFDM data up to 2 Gb/s with EVM, SNR and BER of 33.5%, 9.51 dB and 1.4 × 10(-3), respectively.
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A TO-38-can packaged Gallium nitride (GaN) blue laser diode (LD) based free-space visible light communication (VLC) with 64-quadrature amplitude modulation (QAM) and 32-subcarrier orthogonal frequency division multiplexing (OFDM) transmission at 9 Gbps is preliminarily demonstrated over a 5-m free-space link. The 3-dB analog modulation bandwidth of the TO-38-can packaged GaN blue LD biased at 65 mA and controlled at 25°C is only 900 MHz, which can be extended to 1.5 GHz for OFDM encoding after throughput intensity optimization. When delivering the 4-Gbps 16-QAM OFDM data within 1-GHz bandwidth, the error vector magnitude (EVM), signal-to-noise ratio (SNR) and bit-error-rate (BER) of the received data are observed as 8.4%, 22.4 dB and 3.5 × 10(-8), respectively. By increasing the encoded bandwidth to 1.5 GHz, the TO-38-can packaged GaN blue LD enlarges its transmission capacity to 6 Gbps but degrades its transmitted BER to 1.7 × 10(-3). The same transmission capacity of 6 Gbps can also be achieved with a BER of 1 × 10(-6) by encoding 64-QAM OFDM data within 1-GHz bandwidth. Using the 1.5-GHz full bandwidth of the TO-38-can packaged GaN blue LD provides the 64-QAM OFDM transmission up to 9 Gbps, which successfully delivers data with an EVM of 5.1%, an SNR of 22 dB and a BER of 3.6 × 10(-3) passed the forward error correction (FEC) criterion.
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The previous literature on working memory (WM) has indicated that verbal materials are dominantly retained in phonological representations, whereas other linguistic information (e.g., orthography, semantics) only contributes to verbal WM minimally, if not negligibly. Although accumulating evidence has suggested that multiple linguistic components jointly support verbal WM, the visual/orthographic contribution has rarely been addressed in alphabetic languages, possibly due to the difficulty of dissociating the effects of word forms from the effects of their pronunciations in relatively shallow orthography. In the present study, we examined whether the orthographic representations of Chinese characters support the retention of verbal materials in this language of deep orthography. In Experiments 1a and 2, we independently manipulated the phonological and orthographic similarity of horizontal and vertical characters, respectively, and found that participants' accuracy of probed serial recall was reduced by both similar pronunciations and shared phonetic radicals in the to-be-remembered stimuli. Moreover, Experiment 1b showed that only the effect of phonological, but not that of orthographic, similarity was affected by concurrent articulatory suppression. Taken together, the present results indicate the indispensable contribution of orthographic representations to verbal WM of Chinese characters, and suggest that the linguistic characteristics of a specific language not only determine long-term linguistic-processing mechanisms, but also delineate the organization of verbal WM for that language.
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Lenguaje , Memoria a Corto Plazo/fisiología , Recuerdo Mental/fisiología , Reconocimiento Visual de Modelos/fisiología , Aprendizaje Seriado/fisiología , Adulto , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
Rationale & Objective: Matrix metalloproteinase 2 (MMP-2) plays an important role in the development of fibrosis, the final common pathway of chronic kidney disease (CKD). This study aimed to assess the relationship between repeated measures of MMP-2 and CKD progression in a large, diverse prospective cohort. Study Design: In a prospective cohort of Chronic Renal Insufficiency Cohort (CRIC) participants (N = 3,827), MMP-2 was measured at baseline. In a case-cohort design, MMP-2 was additionally measured at year 2 in a randomly selected subcohort and cases of estimated glomerular filtration rate (eGFR) halving or kidney replacement therapy (KRT) (N = 1,439). Setting & Participants: CRIC is a multicenter prospective cohort of adults with CKD. Exposure: MMP-2 measured in plasma at baseline and at year 2. Outcomes: A composite kidney endpoint (KRT/eGFR halving). Analytical Approach: Weighted Cox proportional hazards models for case-cohort participants. Results: Participants were followed for a median of 4.6 years from year 2 and 6.9 years from the baseline. Persistently elevated MMP-2 (≥300 ng/mL at both baseline and year 2) increased the hazard of the composite kidney endpoint (HR, 1.61; 95% CI, 1.07-2.42; P = 0.09) after adjusting for covariates. The relationship of persistently elevated MMP-2 was modified by levels of inflammation, with a 2.6 times higher rate of the composite kidney endpoint in those with high-sensitivity C-reactive protein < 2.5 g/dL at study entry. Heterogeneity of effect was found with proteinuria, with a baseline MMP-2 level of ≥300 ng/mL associated with an increased risk of the composite kidney endpoint (HR, 1.30; 95% CI, 1.09-1.54) only with proteinuria ≥ 442 mg/g. Limitations: The observational study design limits causal interpretation. Conclusions: Elevated MMP-2 is associated with CKD progression, particularly among those with low inflammation and those with proteinuria. Future investigations are warranted to confirm the reduction in risk of CKD progression among these subgroups of patients with CKD.
Matrix metalloproteinase 2 (MMP-2) is a matrix-degrading protease involved in fibrosis and elevated in chronic kidney disease (CKD). Longitudinal patterns of MMP-2 have not previously been assessed as a predictor of CKD progression in a large prospective cohort. Here, we found that a higher baseline level and an increasing or persistently elevated 2-year pattern of MMP-2 were associated with CKD progression, independent of all covariates except proteinuria. The association of baseline MMP-2 with CKD progression differed by level of proteinuria, whereas levels of inflammation modified the associations of 2-year MMP-2 patterns with CKD progression.
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We constructed a hybrid model of harmonic and anharmonic oscillators to compute Franck-Condon factors and interpret the photoelectron spectrum of methylketene. The equilibrium structures of methylketene and its cation were optimized, and then, the harmonic and anharmonic vibrational frequencies were computed using the B3LYP, PBE0, APFD, and ωB97XD approaches of the density functional theory. The photoelectron spectrum of methylketene was simulated by computing the Franck-Condon factors with both the harmonic and hybrid models. The adiabatic ionization energy of methylketene was computed by using the CCSD(T) approach extrapolating to the complete basis set limit. The simulated photoelectron spectra are consistent with those from the experiment for both the harmonic and hybrid models. However, the error in band positions is reduced by using the hybrid model. The computed adiabatic ionization energies of methylketene are in agreement with the experiment, with the smallest error being 0.017 eV. Our interpretation based on the theoretical spectrum led to the reassignment of the experimental photoelectron spectrum of methylketene.
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Background: The locus coeruleus (LC) produces catecholamines (norepinephrine and dopamine) and is implicated in a broad range of cognitive functions including attention and executive function. Recent advancements in magnetic resonance imaging (MRI) approaches allow for the visualization and quantification of LC structure. Human research focused on the LC has since exploded given the LC's role in cognition and relevance to current models of psychopathology and neurodegenerative disease. However, it is unclear to what extent LC structure reflects underlying catecholamine function, and how LC structure and neurochemical function are collectively associated with cognitive performance. Methods: A partial least squares correlation (PLSC) analysis was applied to 19 participants' LC structural MRI measures and catecholamine synthesis capacity measures assessed using [18F]Fluoro-m-tyrosine ([18F]FMT) positron emission tomography (PET). Results: We found no direct association between LC-MRI and LC-[18F]FMT measures for rostral, middle, or caudal portions of the LC. We found significant associations between LC neuroimaging measures and neuropsychological performance that were driven by rostral and middle portions of the LC, which is in line with LC cortical projection patterns. Specifically, associations with executive function and processing speed arose from contributions of both LC structure and interactions between LC structure and catecholamine synthesis capacity. Conclusion: These findings leave open the possibility that LC MRI and PET measures contribute unique information and suggest that their conjoint use may increase sensitivity to brain-behavior associations in small samples.
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The n-type transition metal oxides (TMO) consisting of molybdenum oxide (MoO(x)) and vanadium oxide (V(2)O(x)) are used as an efficient hole extraction layer (HEL) in heterojunction ZnO/PbS quantum dot solar cells (QDSC). A 4.4% NREL-certified device based on the MoO(x) HEL is reported with Al as the back contact material, representing a more than 65% efficiency improvement compared with the case of Au contacting the PbS quantum dot (QD) layer directly. We find the acting mechanism of the hole extraction layer to be a dipole formed at the MoO(x) and PbS interface enhancing band bending to allow efficient hole extraction from the valence band of the PbS layer by MoO(x). The carrier transport to the metal anode is likely enhanced through shallow gap states in the MoO(x) layer.
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Empirical evidence has shown that visually enhancing the saliency of reward probabilities can ease the cognitive demands of value comparisons and improve value-based decisions in old age. In the present study, we used a time-varying drift diffusion model that includes starting time parameters to better understand (1) how increasing the saliency of reward probabilities may affect the dynamics of value-based decision-making and (2) how these effects may interact with age. We examined choices made by younger and older adults in a mixed lottery choice task. On a subset of trials, we used a color-coding scheme to highlight the saliency of reward probabilities, which served as a decision-aid. The results showed that, in control trials, older adults started to consider probability relative to magnitude information sooner than younger adults, but that their evidence accumulation processes were less sensitive to reward probabilities than that of younger adults. This may indicate a noisier and more stochastic information accumulation process during value-based decisions in old age. The decision-aid increased the influence of probability information on evidence accumulation rates in both age groups, but did not alter the relative timing of accumulation for probability versus magnitude in either group.
Asunto(s)
Toma de Decisiones , Recompensa , Cognición , ProbabilidadRESUMEN
Aging attenuates frontostriatal network functioning, which could lead to deficits in value computation when decision-making involves uncertainty. Although it has been shown that visually enhancing information saliency of outcome probability can improve decision-making in old age, mechanisms of this effect are still unclear. In the present study, the saliency of outcome probability was increased using a color-coding scheme as a decision aid in a mixed lottery choice task, and spontaneous eye-blink rate and pupillary responses were assessed in younger and older adults. Older adults showed lower value sensitivity than younger adults; however, increasing information saliency benefitted choice behaviors in both age groups. Furthermore, the decision aid reduced pupil size during decision-making in both age groups, suggesting that enhancing information saliency decreases cognitive demands of value computation. Baseline value sensitivity was negatively correlated with benefit of enhancing information saliency only in older adults. As value representations in older decision makers are less distinctive at baseline, they may have required more environmental compensation than younger adults.
Asunto(s)
Envejecimiento/psicología , Conducta de Elección/fisiología , Toma de Decisiones/fisiología , Procesos Mentales/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Parpadeo/fisiología , Cognición/fisiología , Humanos , Persona de Mediana Edad , Pupila/fisiología , Adulto JovenRESUMEN
Polymer solar cells (PSCs) are commonly composed of a blend film of a conjugated polymer donor and a soluble C(60) derivative acceptor sandwiched between an ITO anode and a low-workfunction metal cathode. Poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM) are the most widely used donor and acceptor materials, respectively. However, the low LUMO energy level of PCBM limits the open circuit voltage (V(oc)) of the P3HT-based PSCs to ca. 0.6 V. Here we synthesized a new soluble C(60) derivative, indene-C(60) bisadduct (ICBA), with a LUMO energy level 0.17 eV higher than that of PCBM. The PSC based on P3HT with ICBA as acceptor shows a higher V(oc) of 0.84 V and higher power conversion efficiency (PCE) of 5.44% under the illumination of AM1.5, 100 mW/cm(2), while the PSC based on P3HT/PCBM displays a V(oc) of 0.58 V and PCE of 3.88% under the same experimental conditions. The results indicate that ICBA is an alternative high-performance acceptor and could be widely used in high-performance PSCs.
RESUMEN
HOMO level of the PBDTTT-based polymer was successfully reduced by introducing an ketone group in place of the ester group. The average PCE of the PBDTTT-based devices reached 6.3% with a champion PCE result of 6.58%. Due to its highly efficient photovoltaic performance and more feasible synthesis approach, PBDTTT-C has the potential to be successfully applied in the large-scale manufacturing of polymer solar cells.