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1.
Front Endocrinol (Lausanne) ; 15: 1343704, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38586461

RESUMEN

Background: To explore the diagnostic accuracy and the optimal cutoff value between the saline infusion test (SIT) and captopril challenge test (CCT) [including the value and suppression of plasma aldosterone concentration (PAC)] for primary aldosteronism (PA) diagnosing. Methods: A total of 318 patients with hypertension were consecutively enrolled, including 126 patients with PA and 192 patients with essential hypertension (EH), in this observational study. The characteristics of patients and laboratory examinations were collected and compared. The comparison between SIT and CCT was carried by drawing the receiver operator characteristic curve (ROC) and calculating the area under the curve (AUC) to explore the diagnostic accuracy and the optimal cutoff value. Results: The average age was 51.59 ± 10.43 in the PA group and 45.72 ± 12.44 in the EH group (p<0.05). The optimal cutoff value was 10.7 ng/dL for post-CCT PAC, 6.8 ng/dL for post-SIT PAC, and 26.9% for suppression of post-CCT PAC. The diagnostic value of post-CCT PAC was the highest with 0.831 for the AUC and 0.552 for the Youden index. The optimal cutoff value for patients who were <50 years old was 11.5 ng/dL for post-CCT PAC and 8.4 ng/dL for post-SIT PAC. The suppression of post-CCT PAC turned to 18.2% for those of age 50 or older. Conclusion: Compared with SIT, CCT had a higher diagnostic value when post-CCT PAC was used as the diagnostic criterion in Chinese people, while the selection of diagnostic thresholds depended on patient age.


Asunto(s)
Captopril , Pueblos del Este de Asia , Hiperaldosteronismo , Humanos , Adulto , Persona de Mediana Edad , Hiperaldosteronismo/diagnóstico , Aldosterona , Hipertensión Esencial/diagnóstico , China/epidemiología
2.
Small ; : e2310584, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38470191

RESUMEN

Renewable energy is crucial for sustainable future, and Cu2 ZnSnS4 (CZTS) based solar cells shine as a beacon of hope. CZTS, composed of abundant, low-cost, and non-toxic elements, shares similarities with Cu(In,Ga)Se2 (CIGS). However, despite its promise and appealing properties for solar cells, CZTS-based solar cells faces performance challenges owing to inherent issues with CZTS material, and conventional substrate structure complexities. This review critically examines these roadblocks, explores ongoing efforts and breakthroughs, providing insight into the evolving landscape of CZTS-based solar cells research. Furthermore, as an optimistic turn in the field, the review first highlights the crucial need to transition to a superstrate structure for CZTS-based single junction devices, and summarizes the substantial progress made in this direction. Subsequently, dive into the discussion about the fascinating realm of CZTS-based tandem devices, providing an overview of the existing literature as well as outlining the possible potential strategies for enhancing the efficiency of such devices. Finally, the review provides a useful outlook that outlines the priorities for future research and suggesting where efforts should concentrate to shape the future of CZTS-based solar cells.

3.
J Am Heart Assoc ; 13(4): e030427, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38348775

RESUMEN

BACKGROUND: This case-control study aimed to determine whether there were differences between patients with essential hypertension with accessory renal arteries (ARAs) and those without ARAs. METHODS AND RESULTS: The enrolled patients with essential hypertension were divided into the ARA group (n=200) and control group without ARAs (n=238). After propensity matching, 394 patients (197 in each of the 2 groups), were included. The 24-hour BP (4.33/2.43 mm Hg) and daytime BP (4.48/2.61 mm Hg) of patients in the ARA group were significantly higher than those of the control group (P<0.05). The flow-mediated dilation was lower in the ARA group (5.98±2.70 versus 5.18±2.66; P<0.05). In correlation analysis, the horizontal plasma aldosterone concentration had the highest correlation with 24-hour, daytime, and nighttime systolic BP (r=0.263, 0.247, and 0.243, respectively; P<0.05) and diastolic BP (r=0.325, 0.298, and 0.317, respectively; P<0.05). As for multivariate regression analysis, plasma aldosterone concentration was a significant risk factor for elevated 24-hour, daytime, and nighttime systolic BP (ß=0.249 [95% CI, 0.150-0.349], 0.228 [95% CI, 0.128-0.329], and 0.282 [95% CI, 0.187-0.377], respectively; P<0.05) and elevated diastolic BP (ß=0.289 [95% CI, 0.192-0.385], 0.256 [95% CI, 0.158-0.353], and 0.335 [95% CI, 0.243-0.427], respectively; P<0.05). Direct renin concentration was also a risk factor for 24-hour and daytime BPs, whereas heart rate was a risk factor correlated with 24-hour, daytime, and nighttime diastolic BP (all P<0.05). For the mixed-effects model for repeated measures, the results were similar to results of the multivariate regression analysis (all P<0.05). CONCLUSIONS: ARAs could contribute a higher BP of patients with essential hypertension and might promote the development of essential hypertension. The mechanism might be related to overactivation of the renin-angiotensin-aldosterone system and sympathetic nervous system.


Asunto(s)
Hipertensión , Humanos , Aldosterona , Estudios de Casos y Controles , Arteria Renal , Monitoreo Ambulatorio de la Presión Arterial , Presión Sanguínea/fisiología , Hipertensión Esencial/diagnóstico
4.
Small ; 20(9): e2307179, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37857576

RESUMEN

Rechargeable battery devices with high energy density are highly demanded by the modern society. The use of lithium (Li) anodes is extremely attractive for future rechargeable battery devices. However, the notorious Li dendritic and instability of solid electrolyte interface (SEI) issues pose series of challenge for metal anodes. Here, based on the inspiration of in situ photoelectrochemical engineering, it is showed that a tailor-made composite photoanodes with good photoelectrochemical properties (Li affinity property and photocatalytic property) can significantly improve the electrochemical deposition behavior of Li anodes. The light-assisted Li anode is accommodated in the tailor-made current collector without uncontrollable Li dendrites. The as-prepared light-assisted Li metal anode can achieve the in situ stabilization of SEI layer under illumination. The corresponding in situ formation mechanism and photocatalytic mechanism of composite photoanodes are systematically investigated via DFT theoretical calculation, ex situ UV-vis and ex situ XPS characterization. It is worth mentioning that the as-prepared composite photoanodes can adapt to the ultra-high current density of 15 mA cm-2 and the cycle capacity of 15 mAh cm-2 under light, showing no dendritic morphology and low hysteresis voltage. This work is of great significance for the commercialization of new generation Li metal batteries.

5.
Adv Mater ; 36(3): e2307733, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37850716

RESUMEN

The Cd-free Cu2 ZnSnS4 (CZTS) solar cell is an ideal candidate for producing low-cost clean energy through green materials owing to its inherent environmental friendliness and earth abundance. Nevertheless, sulfide CZTS has long suffered from severe open-circuit voltage (VOC ) deficits, limiting the full exploitation of performance potential and further progress. Here, an effective strategy is proposed to alleviate the nonradiative VOC loss by manipulating the phase evolution during the critical kesterite phase formation stage. With a Ge cap layer on the precursor, premature CZTS grain formation is suppressed at low temperatures, leading to fewer nucleation centers at the initial crystallization stage. Consequently, the CZTS grain formation and crystallization are deferred to high temperatures, resulting in enhanced grain interior quality and less unfavorable grain boundaries in the final film. As a result, a champion efficiency of 10.7% for Cd-free CZTS solar cells with remarkably high VOC beyond 800 mV (63.2% Schockley-Queisser limit) is realized, indicating that nonradiative recombination is effectively inhibited. This strategy may advance other compound semiconductors seeking high-quality crystallization.

6.
Nanomaterials (Basel) ; 13(20)2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37887913

RESUMEN

Massive emissions of carbon dioxide (CO2) have caused environmental issues like global warming, which needs to be addressed. Researchers have developed numerous methods to reduce CO2 emissions. Among these, photoelectrochemical (PEC) CO2 reduction is a promising method for mitigating CO2 emissions. Recently, Cu2ZnSnS4 (CZTS) has been recognized as good photocathode candidate in PEC systems for CO2 reduction due to its earth abundance and non-toxicity, as well as its favourable optical/electrical properties. The performance of PEC CO2 reduction can be evaluated based on its efficiency, selectivity, and stability, which are significantly influenced by the photocathode materials. As a result, researchers have applied various strategies to improve the performance of CZTS photocathodes, including band structure engineering and surface catalytic site engineering. This review provides an overview of advanced methods to enhance the PEC systems for CO2 reduction, focusing on CZTS.

7.
J Gen Virol ; 104(10)2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37862073

RESUMEN

Chikungunya virus (CHIKV) is an alphavirus, transmitted by Aedes species mosquitoes. The CHIKV single-stranded positive-sense RNA genome contains two open reading frames, coding for the non-structural (nsP) and structural proteins of the virus. The non-structural polyprotein precursor is proteolytically cleaved to generate nsP1-4. Intriguingly, most isolates of CHIKV (and other alphaviruses) possess an opal stop codon close to the 3' end of the nsP3 coding sequence and translational readthrough is necessary to produce full-length nsP3 and the nsP4 RNA polymerase. Here we investigate the role of this stop codon by replacing the arginine codon with each of the three stop codons in the context of both a subgenomic replicon and infectious CHIKV. Both opal and amber stop codons were tolerated in mammalian cells, but the ochre was not. In mosquito cells all three stop codons were tolerated. Using SHAPE analysis we interrogated the structure of a putative stem loop 3' of the stop codon and used mutagenesis to probe the importance of a short base-paired region at the base of this structure. Our data reveal that this stem is not required for stop codon translational readthrough, and we conclude that other factors must facilitate this process to permit productive CHIKV replication.


Asunto(s)
Aedes , Fiebre Chikungunya , Virus Chikungunya , Animales , Virus Chikungunya/genética , Codón de Terminación/genética , Codón de Terminación/metabolismo , Fiebre Chikungunya/genética , Proteínas no Estructurales Virales/genética , Replicación Viral/genética , Mamíferos/genética , Mamíferos/metabolismo
8.
Small ; 19(50): e2303745, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37616514

RESUMEN

Rechargeable battery devices with high energy density are highly demanded by  our  modern society. The use of metal anodes is extremely attractive for future rechargeable battery devices. However, the notorious metal dendritic and instability of solid electrolyte interface issues pose a series of challenges for metal anodes. Recently, considering the indigestible dynamical behavior of metal anodes, photoelectrochemical engineering of light-assisted metal anodes have been rapidly developed since they efficiently utilize the integration and synergy of oriented crystal engineering and photocatalysis engineering, which provided a potential way to unlock the interface electrochemical mechanism and deposition reaction kinetics of metal anodes. This review starts with the fundamentals of photoelectrochemical engineering and follows with the state-of-art advance of photoelectrochemical engineering for light-assisted rechargeable metal batteries where photoelectrode materials, working principles, types, and practical applications are explained. The last section summarizes the major challenges and some invigorating perspectives for future research on light-assisted rechargeable metal batteries.

9.
Small ; 19(47): e2304045, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37485629

RESUMEN

The design of a novel photoelectric integrated system is considered to be an efficient way to utilize and store inexhaustible solar energy. However, the mechanism of photoelectrode under illuminate conditions is still unclear. Density functional theory (DFT) provides standardized analysis and becomes a powerful way to explain the photoelectrochemical mechanism. Herein, the feasibility of four metal oxide configurations as photoelectrode materials by using a high throughput calculation method based on DFT are investigated. According to the photoelectrochemical properties, band structure and density of states are calculated, and the intercalate/deintercalate simulation is performed with adsorption configuration. The calculation indicates that the band gap of Fe2 CoO4 (2.404 eV) is narrower than that of Co3 O4 (2.553 eV), as well as stronger adsorption energy (-3.293 eV). The relationship between the electronic structure and the photoelectrochemical performance is analyzed and verified according to the predicted DFT results by subsequent experiments. Results show that the Fe2 CoO4 photoelectrode samples exhibit higher coulombic efficiency (97.4%) than that under dark conditions (94.9%), which is consistent with the DFT results. This work provides a general method for the design of integrated photoelectrode materials and is expected to be enlightening for the adjustment of light-assisted properties of multifunctional materials.

10.
Adv Mater ; 35(42): e2303936, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37453141

RESUMEN

Thin-film solar cells are expected to play a significant role in the space industry, building integrated photovoltaic (BIPV), indoor applications, and tandem solar cells, where bifaciality and semitransparency are highly desired. Sb2 (S,Se)3 has emerged as a promising new photovoltaic (PV) material for its high absorption coefficient, tunable bandgap, and nontoxic and earth-abundant constituents. However, high-efficiency Sb2 (S,Se)3 solar cells exclusively employ monofacial architectures, leaving a considerable gap toward large-scale application in aforementioned fields. Here, a bifacial and semitransparent Sb2 (S,Se)3 solar cell and its extended application in tandem solar cells are reported. The transparent conductive oxides (TCOs) and the ultrathin inner n-i-p structure provide high long-wavelength transmittance. Despite the MnS/ITO Schottky junction, power conversion efficiencies (PCEs) of 7.41% and 6.36% are achieved with front and rear illumination, respectively, contributing to a great bifaciality of 0.86. Consequently, the reported device gains great enhancement in PV performance by exploiting albedo of surroundings and shows exceptional capability in absorbing tilt incident light. Moreover, an Sb2 (S,Se)3 /Si tandem solar cell with a PCE of 11.66% is achieved in preliminary trials. These exciting findings imply that bifacial and semitransparent Sb2 (S,Se)3 solar cells possess tremendous potential in practical applications based on their unique characteristics.

11.
Front Genet ; 14: 1101612, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37265961

RESUMEN

Objective: This study aimed to identify immune infiltration characteristics and new immunological diagnostic biomarkers in the cerebrovascular tissue of moyamoya disease (MMD) using bioinformatics analysis. Methods: GSE189993 and GSE141022 were downloaded from the GEO database. Differentially expressed gene and PPI analysis were performed. After performing WGCNA, the most significant module associated with MMD was obtained. Next, functional pathways according to GSEA, GO, and KEGG were enriched for the aforementioned core genes obtained from PPI and WGCNA. Additionally, immune infiltration, using the CIBERSORT deconvolution algorithm, immune-related biomarkers, and the relationship between these genes, was further explored. Finally, diagnostic accuracy was verified with ROC curves in the validation dataset GSE157628. Results: A total of 348 DEGs were screened, including 89 downregulated and 259 upregulated genes. The thistlel module was detected as the most significant module associated with MMD. Functional analysis of the core genes was chiefly involved in the immune response, immune system process, protein tyrosine kinase activity, secretory granule, and so on. Among 13 immune-related overlapping genes, 4 genes (BTK, FGR, PTPN11, and SYK) were identified as potential diagnostic biomarkers, where PTPN11 showed the highest specificity and sensitivity. Meanwhile, a higher proportion of eosinophils, not T cells or B cells, was demonstrated in the specific immune infiltration landscape of MMD. Conclusion: Immune activities and immune cells were actively involved in the progression of MMD. BTK, FGR, PTPN11, and SYK were identified as potential immune diagnostic biomarkers. These immune-related genes and cells may provide novel insights for immunotherapy in the future.

12.
Materials (Basel) ; 16(4)2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36837059

RESUMEN

Recently, Prussian blue analogues (PBAs)-based anode materials (oxides, sulfides, selenides, phosphides, borides, and carbides) have been extensively investigated in the field of energy conversion and storage. This is due to PBAs' unique properties, including high theoretical specific capacity, environmental friendly, and low cost. We thoroughly discussed the formation of PBAs in conjunction with other materials. The performance of composite materials improves the electrochemical performance of its energy storage materials. Furthermore, new insights are provided for the manufacture of low-cost, high-capacity, and long-life battery materials in order to solve the difficulties in different electrode materials, combined with advanced manufacturing technology and principles. Finally, PBAs and their composites' future challenges and opportunities are discussed.

13.
Sci Rep ; 13(1): 3251, 2023 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-36828875

RESUMEN

Moyamoya disease (MMD) is a chronic occlusive cerebrovascular disease that can be treated with revascularization. Surgery increases the risk of poor wound healing (PWH) due to the impact on the blood supply to the flap. We aimed to analyze risk factors for PWH in MMD with a complete Y-shaped incision. A total of 125 patients with MMD were enrolled in this prospective observational study. The wounds were assessed and measured on the third and seventh days after surgery. The mean age of these patients was 43.3 ± 10.0 years. The ratio of male to female was 1:1.3. 15 (12.0%) patients had incision complications. 5 patients (4.0%) had redness; 2 patients (1.6%) had swelling; 2 patients (1.6%) had fat necrosis; 3 patients (2.4%) had incision infection; and 3 patients (2.4%) had flap necrosis. Student's t test showed significant differences in BMI (P = 0.040) and fever time (P = 0.050). The standard chi-squared test showed significant differences in incision infection (P = 0.010), suture mode (P = 0.047), and cutting off large branch vessels in the flap (P < 0.001). Multivariate logistic regression analysis suggested that incision infection (P = 0.026, OR 12.958), using a skin stapler (P = 0.030, OR 4.335), cutting off large branch vessels in the flap (P = 0.009, OR 5.227), and BMI (P = 0.027, OR 1.204) were risk factors. The area under the curve for risk factors for PWH on a receiver operating characteristic curve was 0.853. Incision infection, using a skin stapler, higher BMI, and cutting off large branch vessels in the flap are risk factors for PWH.


Asunto(s)
Enfermedad de Moyamoya , Herida Quirúrgica , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Enfermedad de Moyamoya/complicaciones , Herida Quirúrgica/complicaciones , Infección de la Herida Quirúrgica/etiología , Factores de Riesgo , Cicatrización de Heridas
14.
Small ; 19(14): e2206848, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36604991

RESUMEN

Great changes have occurred in the energy storage area in recent years as a result of rapid economic expansion. People have conducted substantial research on sustainable energy conversion and storage systems in order to mitigate the looming energy crisis. As a result, developing energy storage materials is critical. Materials with an open frame structure are known as Prussian blue analogs (PBAs). Anode materials for oxides, sulfides, selenides, phosphides, borides, and carbides have been extensively explored as anode materials in the field of energy conversion and storage in recent years. The advantages and disadvantages of oxides, sulfides, selenides, phosphides, borides, carbides, and other elements, as well as experimental methodologies and electrochemical properties, are discussed in this work. The findings reveal that employing oxides, sulfides, selenides, phosphides, borides, and other electrode materials to overcome the problems of low conductivity, excessive material loss, and low specific volume is ineffective. Therefore, this review intends to address the issues of diverse energy storage materials by combining multiple technologies to manufacture battery materials with low cost, large capacity, and extended service life.

17.
Heliyon ; 8(12): e12159, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36544837

RESUMEN

To explore the hemodynamic changes of the superficial temporal artery in adult Moyamoya Disease (MMD) who underwent combined revascularization surgery. A number of 40 patients with MMD were enrolled, and all of them underwent a direct superficial temporal artery (STA)-middle cerebral artery (STA-MCA) bypass combined with an encephalo-duro-arterio-synangiosis (EDAS). Hemodynamic parameters were detected by Color Doppler Ultrasonography (CDUS) at the preoperative, perioperative and follow-up time, including peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistance index (RI). The control group were selected randomly during the same period. Researchers applied the SPSS 21 to conduct the two-sample analysis, Chi-Squared test and one-way repeated measures ANOVA between groups. P < 0.05 was considered statistically significant. In this study, 21 males and 19 females with an average age of 44.9 years (Range 28 y-56 y) were enrolled in the MMD group. Among them, 21 patients (52.5%) had perioperative complications, and all symptoms were transient neurological dysfunctions. Intermittent speech disorder was the most common complication during the period of operation. The preoperative hemodynamic of STA showed no significant difference between MMD and the control group. The perioperative hemodynamics had significant carnages compared with preoperative, and there was a trend of fluctuation. The perioperative PSV in the group with complications was significantly higher than the group without complications, except for EDV and RI. In the follow-up ( X ¯ = 5 months), PSV (60.21 ± 22.24 cm/s, P = 0.712) showed no difference compared with baseline data, while EDV (25.12 ± 9.94 cm/s, P = 0.000) and RI (0.575 ± 0.092, P = 0.000) showed significant difference between MMD and control group. The blood flow spectrogram showed high resistance in preoperative, but most patients showed a low resistance pattern during the follow-up time. It was the first time to demonstrate that the hemodynamic changes of STA fluctuated significantly within one week and eventually remained stable after combined revascularization. The PSV may play a more important role in postoperative complications. In the follow-up, PSV had no significant difference, EDV increased significantly, and RI decreased significantly. The blood flow spectrogram mainly shows a low resistance pattern when the hemodynamic is stable.

18.
Small ; 18(50): e2204392, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36319478

RESUMEN

Small grain size and near-horizontal grain boundaries are known to be detrimental to the carrier collection efficiency and device performance of pure-sulfide Cu2 ZnSnS4 (CZTS) solar cells. However, forming large grains spanning the absorber layer while maintaining high electronic quality is challenging particularly for pure sulfide CZTS. Herein, a liquid-phase-assisted grain growth (LGG) model that enables the formation of large grains spanning across the CZTS absorber without compromising the electronic quality is demonstrated. By introducing a Ge-alloyed CZTS nanoparticle layer at the bottom of the sputtered precursor, a Cu-rich and Sn-rich liquid phase forms at the high temperature sulfurization stage, which can effectively remove the detrimental near-horizontal grain boundaries and promote grain growth, thus greatly improving the carrier collection efficiency and reducing nonradiative recombination. The remaining liquid phase layer at the rear interface shows a high work function, acting as an effective hole transport layer. The modified morphology greatly increases the short-circuit current density and fill factor, enabling 10.3% efficient green Cd-free CZTS devices. This work unlocks a grain growth mechanism, advancing the morphology control of sulfide-based kesterite solar cells.

19.
JAMA Netw Open ; 5(10): e2236057, 2022 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-36223120

RESUMEN

Importance: Reduced exercise capacity is commonly reported among individuals with COVID-19 symptoms more than 3 months after SARS-CoV-2 infection (long COVID-19 [LC]). Cardiopulmonary exercise testing (CPET) is the criterion standard to measure exercise capacity and identify patterns of exertional intolerance. Objectives: To estimate the difference in exercise capacity among individuals with and without LC symptoms and characterize physiological patterns of limitations to elucidate possible mechanisms of LC. Data Sources: A search of PubMed, EMBASE, Web of Science, preprint servers, conference abstracts, and cited references was performed on December 20, 2021, and again on May 24, 2022. A preprint search of medrxiv.org, biorxiv.org, and researchsquare.com was performed on June 9, 2022. Study Selection: Studies of adults with SARS-CoV-2 infection more than 3 months earlier that included CPET-measured peak oxygen consumption (V̇o2) were screened independently by 2 blinded reviewers; 72 (2%) were selected for full-text review, and 35 (1%) met the inclusion criteria. An additional 3 studies were identified from preprint servers. Data Extraction and Synthesis: Data extraction was performed by 2 independent reviewers according to the PRISMA reporting guideline. Data were pooled using random-effects models. Main Outcomes and Measures: Difference in peak V̇o2 (in mL/kg/min) among individuals with and without persistent COVID-19 symptoms more than 3 months after SARS-CoV-2 infection. Results: A total of 38 studies were identified that performed CPET on 2160 individuals 3 to 18 months after SARS-CoV-2 infection, including 1228 with symptoms consistent with LC. Most studies were case series of individuals with LC or cross-sectional assessments within posthospitalization cohorts. Based on a meta-analysis of 9 studies including 464 individuals with LC symptoms and 359 without symptoms, the mean peak V̇o2 was -4.9 (95% CI, -6.4 to -3.4) mL/kg/min among those with symptoms with a low degree of certainty. Deconditioning and peripheral limitations (abnormal oxygen extraction) were common, but dysfunctional breathing and chronotropic incompetence were also described. The existing literature was limited by small sample sizes, selection bias, confounding, and varying symptom definitions and CPET interpretations, resulting in high risk of bias and heterogeneity. Conclusions and Relevance: The findings of this systematic review and meta-analysis study suggest that exercise capacity was reduced more than 3 months after SARS-CoV-2 infection among individuals with symptoms consistent with LC compared with individuals without LC symptoms, with low confidence. Potential mechanisms for exertional intolerance other than deconditioning include altered autonomic function (eg, chronotropic incompetence, dysfunctional breathing), endothelial dysfunction, and muscular or mitochondrial pathology.


Asunto(s)
COVID-19 , Adulto , COVID-19/complicaciones , COVID-19/diagnóstico , Estudios Transversales , Prueba de Esfuerzo , Humanos , Oxígeno , SARS-CoV-2 , Síndrome Post Agudo de COVID-19
20.
J Phys Chem Lett ; 13(40): 9355-9362, 2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36190250

RESUMEN

Analogous to black phosphorus, SnS processes folded structure that shows a strongly anisotropic optical absorption. Herein, by using ultrafast two-color pump and probe spectroscopy, the azimuthal angle dependence of nonlinear optical anisotropy in SnS is investigated. After 390 nm photoexcitation, the reflectivity of the 780 nm probe beam is first reduced significantly, followed by a complex alternation with the rotation of the sample along the c-axis. The relaxation of reflectivity consisted of two components: a 1-3 ps fast process that shows azimuthal angle and pump fluence dependence, which arises from electron-phonon coupling. The slow process shows strongly azimuthal angle dependence, which arises from the recovery of a photoinduced structural change, i.e., from the photoinduced metastable state with Cmcm-like symmetry to the initial state with Pnma symmetry. In addition, a coherent acoustic phonon with a frequency of 40 GHz is also identified, which originates from the temperature gradient-induced strain wave in the SnS crystal.

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