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1.
Chem Rev ; 124(8): 5119-5166, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38619540

RESUMEN

Highly efficient coelectrolysis of CO2/H2O into syngas (a mixture of CO/H2), and subsequent syngas conversion to fuels and value-added chemicals, is one of the most promising alternatives to reach the corner of zero carbon strategy and renewable electricity storage. This research reviews the current state-of-the-art advancements in the coelectrolysis of CO2/H2O in solid oxide electrolyzer cells (SOECs) to produce the important syngas intermediate. The overviews of the latest research on the operating principles and thermodynamic and kinetic models are included for both oxygen-ion- and proton-conducting SOECs. The advanced materials that have recently been developed for both types of SOECs are summarized. It later elucidates the necessity and possibility of regulating the syngas ratios (H2:CO) via changing the operating conditions, including temperature, inlet gas composition, flow rate, applied voltage or current, and pressure. In addition, the sustainability and widespread application of SOEC technology for the conversion of syngas is highlighted. Finally, the challenges and the future research directions in this field are addressed. This review will appeal to scientists working on renewable-energy-conversion technologies, CO2 utilization, and SOEC applications. The implementation of the technologies introduced in this review offers solutions to climate change and renewable-power-storage problems.

2.
Neurobiol Dis ; 190: 106379, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38104911

RESUMEN

BACKGROUND: Cognitive impairment is a serious nonmotor symptom in patients with Parkinson's disease (PD). Currently, there are few studies investigating the relationship of serum markers and retinal structural changes with cognitive function in PD. OBJECTIVE: To investigate the relationship between retinal structural changes, serum high mobility group box-1 (HMGB1) levels and cognitive function and motor symptoms in PD patients. METHODS: Eighty-nine participants, including 47 PD patients and 42 healthy subjects, were enrolled. PD patients were divided into Parkinson's disease with normal cognitive (PD-NC), Parkinson's disease with mild cognitive impairment (PD-MCI), and Parkinson's disease with dementia (PDD) groups. The motor and nonmotor symptoms of PD patients were evaluated with clinical scale. Serum HMGB1 levels were detected by enzyme-linked immunosorbent assay (ELISA), and ganglion cell-inner plexiform layer complex (GCIPL) thickness changes in the macula were quantitatively analyzed by swept source optical coherence tomography (SS-OCT) in all patients. RESULTS: Compared with the control group, the macular GCIPL (t = -2.308, P = 0.023) was thinner and serum HMGB1 (z = -2.285, P = 0.022) was increased in PD patients. Macular GCIPL thickness in patients with PD-MCI and PDD were significantly lower than that in PD-NC patients, but there were no significant difference between the PD-MCI and PDD groups. Serum HMGB1 levels in patients with PD-MCI and PDD were significantly higher than those in PD-NC patients, and serum HMGB1 levels in PDD patients were higher than those in PD-MCI patients. Correlation analysis showed that serum HMGB1 levels in PD patients were positively correlated with disease duration, HY stage, UPDRS-I score, UPDRS-III score, and UPDRS total score and negatively correlated with MOCA score. Macular GCIPL thickness was negatively correlated with HY stage and positively correlated with MOCA score, and macular GCIPL thickness was negatively correlated with serum HMGB1 level. Logistic regression analysis showed that elevated serum HMGB1 level, thinner macular GCIPL thickness, and higher HY stage were independent risk factors for Parkinson's disease with cognitive impairment (PD-CI). The areas under the receiver operating characteristic curve (AUC) for the serum HMGB1 level and macular GCIPL thickness-based diagnosis of PD-MCI, PDD and PD-CI based on in patients with PD were 0.786 and 0.825, 0.915 and 0.856, 0.852 and 0.841, respectively. The AUC for the diagnosis of PD-MCI, PDD and PD-CI with serum HMGB1 level and GCIPL thickness combined were 0.869, 0.967 and 0.916, respectively. CONCLUSION: The macular GCIPL thickness and serum HMGB1 level are potential markers of cognitive impairment in PD patients, and their combination can significantly improve the accuracy of the diagnosis of cognitive impairment in PD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Proteína HMGB1 , Enfermedad de Parkinson , Humanos , Cognición , Retina
3.
Eur J Neurosci ; 59(10): 2702-2714, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38469656

RESUMEN

This study aims to analyse hyperechoic substantia nigra (HSN) characteristics and the correlation of HSN with clinical features and blood biomarkers in patients with Parkinson's disease (PD). Transcranial sonography (TCS) evaluations of the substantia nigra (SN) were performed in 40 healthy controls and 71 patients with PD, including patients with SN hyperechogenicity (SN+) and those with normal SN echogenicity (SN-). Evaluation of motor and non-motor symptoms was assessed by a series of rating scales. The uricase method was used to determine serum uric acid (UA) levels, and enzyme-linked immunosorbent assay (ELISA) was used to measure plasma interleukin (IL)-1ß levels. TCS showed 92.50% specificity and 61.97% sensitivity in differentiating PD patients from controls. The area of SN+ contralateral to the side of initial motor symptoms (SNcontra) was larger than that ipsilateral to the side of initial motor symptoms (SNipsi). The PDSN+ group had lower Argentine Hyposmia Rating Scale (AHRS) scores and UA levels than the PDSN- group. Binary logistic regression analysis revealed that AHRS scores and UA levels could be independent predictors for HSN. The larger SN echogenic area (SNL) sizes positively correlated with plasma IL-1ß levels in PD patients with SN+. The present study provides further evidence of the potential of SN echogenicity as an imaging biomarker for PD diagnosis. PD patients with HSN have more severe non-motor symptoms of hyposmia. HSN in PD patients is related to the mechanism of abnormal iron metabolism and microglial activation.


Asunto(s)
Interleucina-1beta , Enfermedad de Parkinson , Sustancia Negra , Ultrasonografía Doppler Transcraneal , Humanos , Enfermedad de Parkinson/diagnóstico por imagen , Masculino , Femenino , Persona de Mediana Edad , Sustancia Negra/diagnóstico por imagen , Sustancia Negra/metabolismo , Anciano , Ultrasonografía Doppler Transcraneal/métodos , Interleucina-1beta/sangre , Interleucina-1beta/metabolismo , Ácido Úrico/sangre , Biomarcadores/sangre
4.
J Neurosci Res ; 102(2): e25303, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38361408

RESUMEN

Lipocalin-2 (LCN2) is essential for the regulation of neuroinflammation and cellular uptake of iron. This study aimed to evaluate plasma LCN2 levels and explore their correlation with clinical and neuroimaging features in Parkinson's disease (PD) patients. Enzyme-linked immunosorbent assay (ELISA) was used to measure plasma LCN2 levels in 120 subjects. Evaluation of motor symptoms and nonmotor symptoms in PD patients was assessed by the associated scales. Voxel-based morphometry (VBM) was used to evaluate brain volume alterations, and quantitative susceptibility mapping (QSM) was used to quantitatively analyze brain iron deposition in 46 PD patients. Plasma LCN2 levels were significantly higher in PD patients than those in healthy controls. LCN2 levels were negatively correlated with Montreal Cognitive Assessment (MoCA) scores, total brain gray matter volume (GMV), and GMV/total intracranial volume (TIV) ratio, but positively correlated with Hamilton Anxiety Rating Scale (HAMD) scores and mean QSM values of the bilateral substantial nigra (SN). Receiver operating characteristic (ROC) curves confirmed that plasma LCN2 levels had good predictive accuracy for PD. The results suggest that plasma LCN2 levels have potential as a biomarker for the diagnosis of PD. LCN2 may be a therapeutic target for neuroinflammation and brain iron deposition.


Asunto(s)
Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico por imagen , Lipocalina 2 , Enfermedades Neuroinflamatorias , Imagen por Resonancia Magnética/métodos , Neuroimagen , Hierro/metabolismo
5.
Opt Express ; 32(2): 1776-1788, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38297722

RESUMEN

We report a real-time 150 kbps stealth transmission within public optical communication of 10 Gbps dual polarization QPSK. The stealth data is modulated onto the frequency tuning signals of a fast-tuning laser source in the transmitter, which causes slight frequency dithering for the transmitted optical signal. In the receiver, the stealth receiver recovers the stealth data from the estimated frequency offset by the QPSK DSP algorithm. The experiments show the stealth transmission has few impacts on the public channel over a 300 km distance. The proposed method is fully compatible with existing optical transmission systems, and the only hardware change is to upgrade the transmitter laser to support frequency tuning through an external analog port for receiving stealth signal. The proposed stealth scheme can combine with cryptographic protocols to improve the integrated security of the system, and can be used as signaling transport for low level network control to reduce the communication overhead.

6.
Nature ; 563(7729): 89-93, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30323288

RESUMEN

Resiliency against eavesdropping and other security threats has become one of the key design considerations for communication systems. As wireless systems become ubiquitous, there is an increasing need for security protocols at all levels, including software (such as encryption), hardware (such as trusted platform modules) and the physical layer (such as wave-front engineering)1-5. With the inevitable shift to higher carrier frequencies, especially in the terahertz range (above 100 gigahertz), an important consideration is the decreased angular divergence (that is, the increased directionality) of transmitted signals, owing to the reduced effects of diffraction on waves with shorter wavelengths. In recent years, research on wireless devices6-8 and systems9-11 that operate at terahertz frequencies has ramped up markedly. These high-frequency, narrow-angle broadcasts present a more challenging environment for eavesdroppers compared to the wide-area broadcasts used at lower frequencies12,13. However, despite the widespread assumption of improved security for high-frequency wireless data links14-16, the possibility of terahertz eavesdropping has not yet been characterized. A few recent studies have considered the issue at lower frequencies5,12,13,17,18, but generally with the idea that the eavesdropper's antenna must be located within the broadcast sector of the transmitting antenna, leading to the conclusion that eavesdropping becomes essentially impossible when the transmitted signal has sufficiently high directionality15. Here we demonstrate that, contrary to this expectation, an eavesdropper can intercept signals in line-of-sight transmissions, even when they are transmitted at high frequencies with narrow beams. The eavesdropper's techniques are different from those for lower-frequency transmissions, as they involve placing an object in the path of the transmission to scatter radiation towards the eavesdropper. We also discuss one counter-measure for this eavesdropping technique, which involves characterizing the backscatter of the channel. We show that this counter-measure can be used to detect some, although not all, eavesdroppers. Our work highlights the importance of physical-layer security in terahertz wireless networks and the need for transceiver designs that incorporate new counter-measures.

7.
Arch Sex Behav ; 53(3): 1107-1114, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38167989

RESUMEN

The diagnostic value of audiovisual sexual stimulation (AVSS) for psychogenic erectile dysfunction (ED) is still unclear. We investigated the independent diagnostic value and optimal cut-off parameter of AVSS for psychogenic ED. All participants had received the AVSS test and nocturnal penile tumescence and rigidity (NPTR) monitoring at least twice. ED patients were divided into psychogenic ED and organic ED according to NPTR examination. The diagnostic accuracy of AVSS parameters was evaluated with the receiver operating characteristic (ROC) curve, and the Youden index was employed to determine the optimal diagnostic cut-off values. A total of 346 patients with ED and 60 healthy men were included in this study, among which 162 and 184 cases of psychogenic and organic ED were identified based on NPTR, respectively. When comparing the two ED groups, the area under the curve (AUC) of AVSS parameters was 0.85-0.89. Six-selected AVSS parameters could precisely diagnose psychogenic ED, exhibiting increased diagnostic specificity compared with corresponding sensitivity. When comparing psychogenic ED with the control group, the AUC of the tumescence of the tip was superior to the AUC other parameters (0.81 vs. 0.58, 0.66, 0.59, 0.53, 0.68), and the best determined diagnostic cut-off value was the tumescence of the tip < 29.87%. Independent AVSS could diagnose psychogenic ED objectively and effectively, and its diagnostic value was highest when 1.50% ≤ tumescence of the tip < 29.87%.


Asunto(s)
Disfunción Eréctil , Masculino , Humanos , Disfunción Eréctil/diagnóstico , Disfunción Eréctil/psicología , Erección Peniana/fisiología , Conducta Sexual
8.
Neurol Sci ; 45(1): 47-54, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37718350

RESUMEN

OBJECTIVE: This study was designed to investigate the diagnostic value of plasma SIRT1 levels and whole-brain gray matter (GM) volume in Parkinson's disease (PD) patients with cognitive impairment. METHODS: Automated enzymatic analysis was performed to measure plasma SIRT1 levels in 80 healthy controls and 77 PD patients. Motor symptoms and nonmotor symptoms in PD patients were assessed using the corresponding scales. A Siemens MAGNETOM Prisma 3 T MRI scanner was used to acquire images in 35 of 77 PD patients. RESULTS: Plasma SIRT1 levels in PD patients were lower than those in healthy controls. Plasma SIRT1 levels were negatively correlated with the age, Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) scores, anxiety, depression, excessive daytime sleepiness (EDS), quality of life, and especially cognitive impairment. Thus, it showed that plasma SIRT1 levels were relevant to visuospatial/executive function, memory, and language. Receiver-operating characteristic (ROC) analysis confirmed that plasma SIRT1 levels had good diagnostic accuracy for PD with anxiety and EDS. Furthermore, plasma SIRT1 levels had a significant positive correlation with GM volume in the whole brain, and ROC analysis confirmed that plasma SIRT1 levels and the total GM volume had good diagnostic accuracy for PD with cognitive impairment. CONCLUSIONS: This study showed that plasma SIRT1 levels were correlated with the nonmotor symptoms of anxiety, depression, EDS, and especially cognitive impairment as well as the total GM volume. Furthermore, the combination of plasma SIRT1 levels and the total GM volume had good diagnostic accuracy for PD with cognitive impairment.


Asunto(s)
Disfunción Cognitiva , Trastornos de Somnolencia Excesiva , Enfermedad de Parkinson , Humanos , Sustancia Gris/diagnóstico por imagen , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico por imagen , Calidad de Vida , Sirtuina 1 , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Encéfalo/diagnóstico por imagen
9.
BMC Public Health ; 24(1): 2225, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39148063

RESUMEN

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative influenced by various clinical factors. The potential relationship between renal function and the risk of PD remains poorly understood. This study aims to explore the association between kidney function and the risk of developing PD. METHODS: A population-based cohort study was conducted using data from 400,571 UK Biobank participants. Renal function was assessed using the estimated glomerular filtration rate (eGFR), calculated from serum creatinine and cystatin C levels. The association between eGFR levels and PD risk was evaluated using univariate and multivariate Cox regression analyses, Restricted Cubic Spline (RCS) analysis, and Kaplan-Meier analysis. Additionally, a clinical prediction model was developed and its diagnostic accuracy was evaluated using ROC analysis. A heatmap was also constructed to examine the relationship between clinical factors and gray matter volume in various brain regions. RESULTS: Over a median observation period of 13.8 years, 2740 PD events were recorded. Cox regression and Kaplan-Meier analyses revealed a significant association between decreased eGFR and increased PD risk, particularly in participants with eGFR < 30 ml/min/1.73 m2. This association was confirmed across three adjusted models. RCS analysis demonstrated a nonlinear relationship between decreasing eGFR and increasing PD risk. Furthermore, changes in eGFR were correlated with alterations in subcortical gray matter volume in regions such as the frontal cortex, striatum, and cerebellum. The clinical prediction model showed high diagnostic accuracy with AUC values of 0.776, 0.780, and 0.824 for 4-, 8-, and 16-year predictions, respectively. CONCLUSION: Renal insufficiency is significantly associated with an increased risk of PD, highlighting the importance of maintaining good kidney function as a potential preventive measure against PD.


Asunto(s)
Tasa de Filtración Glomerular , Enfermedad de Parkinson , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cistatina C/sangre , Tasa de Filtración Glomerular/fisiología , Enfermedad de Parkinson/epidemiología , Enfermedad de Parkinson/fisiopatología , Estudios Prospectivos , Factores de Riesgo , Biobanco del Reino Unido , Reino Unido/epidemiología
10.
J Anim Physiol Anim Nutr (Berl) ; 108(4): 1072-1082, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38528677

RESUMEN

This study aimed to investigate the effects of fermented tofu processing wastewater (FTPW) on the growth performance and meat quality of Xianghuang broilers. A total of 160 six-week-old Xianghuang broilers were randomly assigned to control or FTPW groups with eight replicate pens of 10 birds each pen. Broilers received the same corn-soybean diet but different water. Broilers received ordinary water in the control group and 40% (volume: volume) FTPW (the solution has been filtered with four layers of sieve, containing Bacillus 1.52 × 10-7 CFU/mL) in FTPW group. The experiment lasted for 30 days. Results indicated that growth performance was not affected by treatment (p > 0.05). The value of pH45 min and a48 h increased and drip loss72 h and toughness decreased in breast muscle when broilers received FTPW solution compared with the control group (p < 0.05). The pH45 min, a45 min, a48 h value and crude fat concentration of thigh muscle were higher in FTPW group than that in control group (p < 0.05). Compared with control group, fibre area decreased but fibre density increased in thigh muscle when Xianghuang chickens supplemented with FTPW solution (p < 0.05). Supplementation of FTPW solution in drinking water significantly decreased malondialdehyde content in the breast muscle of Xianghuang chickens (p < 0.05). Gene expressions such as carnitine palmitoyltransferase 1A (CPT1) and glycogen synthase of breast muscle were downregulated in experimental group when compared with control group. In conclusion, FTPW supplementation in drinking water could improve meat quality of Xianghuang broilers by regulating pH value, redness and fibre morphology.


Asunto(s)
Alimentación Animal , Pollos , Dieta , Fermentación , Carne , Aguas Residuales , Animales , Carne/normas , Alimentación Animal/análisis , Dieta/veterinaria , Aguas Residuales/química , Alimentos de Soja , Fenómenos Fisiológicos Nutricionales de los Animales , Manipulación de Alimentos
11.
Small ; 19(29): e2300009, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36964988

RESUMEN

Three-dimensional (3D) structures constructed via coordination-driven self-assemblies have recently garnered increasing attention due to the challenges in structural design and potential applications. In particular, developing new strategy for the convenient and precise self-assemblies of 3D supramolecular structures is of utmost interest. Introducing the concept of self-coordination ligands, herein the design and synthesis of two meta-modified terpyridyl ligands with selective self-complementary coordination moiety are reported and their capability to assemble into two hourglass-shaped nanocages SA and SB is demonstrated. Within these 3D structures, the meta-modified terpyridyl unit preferably coordinates with itself to serve as concave part. By changing the arm length of the ligands, hexamer (SA) and tetramer (SB) are obtained respectively. In-depth studies on the assembly mechanism of SA and SB indicate that the dimers could be formed first via self-complementary coordination and play crucial roles in controlling the final structures. Moreover, both SA and SB can go through hierarchical self-assemblies in solution as well as on solid-liquid interface, which are characterized by transmission electron microscope (TEM) and scanning tunneling microscopy (STM). It is further demonstrated that various higher-order assembly structures can be achieved by tuning the environmental conditions.

12.
Neurol Sci ; 44(3): 881-887, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36383265

RESUMEN

BACKGROUND: Insulin-like growth factor 1 (IGF-1) and epidermal growth factor (EGF) exert neuroprotective effects in Parkinson's disease (PD). To date, studies on the relationships between serum IGF-1 and EGF levels and nonmotor symptoms in PD patients have been rare. METHODS: A Siemens automatic chemical analyzer was used to determine serum IGF-1 levels, and enzyme-linked immunosorbent assay was used to detect serum EGF levels in 100 healthy controls and 100 PD patients, including those in the early (n = 49) and middle-late (n = 51) stage of the disease. Evaluation of motor symptoms and nonmotor symptoms in PD patients was assessed by the associated scales. RESULTS: Serum IGF-1 and EGF levels were higher in PD patients than in healthy controls, and serum IGF-1 and EGF levels were higher in early stage PD patients than in middle-late stage PD patients. Serum IGF-1 levels were significantly negatively correlated with anxiety, depression, and cognitive dysfunction; serum EGF levels were significantly negatively correlated with cognitive dysfunction. Combining IGF-1 and EGF in the diagnosis of PD was more valuable than using a single factor in the diagnosis. CONCLUSIONS: This study shows that serum IGF-1 levels were correlated with the nonmotor symptoms of anxiety, depression, and cognitive dysfunction and that EGF levels were correlated with cognitive dysfunction. The combination of IGF-1 and EGF increased the value for a PD diagnosis. This is the first report of the simultaneous detection of IGF-1 and EGF levels to explore the correlation with nonmotor symptoms of PD.


Asunto(s)
Disfunción Cognitiva , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico , Factor de Crecimiento Epidérmico , Factor I del Crecimiento Similar a la Insulina/metabolismo , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Cognición
13.
Neurol Sci ; 44(12): 4333-4342, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37452260

RESUMEN

BACKGROUND: Dopamine dysregulation syndrome (DDS) is a complication of Parkinson's disease (PD) that seriously affects the quality of life of PD patients. Currently, the risk factors for DDS are poorly known, and it is critical to identify them in the early stages of PD. OBJECTIVE: To explore the incidence of and risk factors for DDS in patients with early PD. METHODS: A retrospective cohort study was conducted on the general data, clinical features, and imaging data of patients with early PD in the PPMI database. Multivariate Cox regression analysis was performed to analyze the risk factors for the development of DDS in patients with early PD, and Kaplan‒Meier curves examined the frequency and predictors of incident DDS symptoms. RESULTS: At baseline, 2.2% (n = 6) of patients with early PD developed DDS, and the cumulative incidence rates of DDS during the 5-year follow-up period were 2.8%, 6.4%, 10.8%, 15.5%, and 18.7%, respectively. In the multivariate Cox regression model controlling for age, sex, and drug use, hypersexuality (HR = 3.088; 95% CI: 1.416~6.732; P = 0.005), compulsive eating (HR = 3.299; 95% CI: 1.665~6.534; P = 0.001), compulsive shopping (HR = 3.899; 95% CI: 1.769~8.593; P = 0.001), anxiety (HR = 4.018; 95% CI: 2.136~7.599; P < 0.01), and lower Hoehn-Yahr (H-Y) stage (HR = 0.278; 95% CI: 0.152~0.509; P < 0.01) were independent risk factors for DDS in patients with early PD. PD patients with DDS had lower DAT uptake values than those patients without DDS. CONCLUSION: Early PD patients with hypersexuality, compulsive eating, compulsive shopping, anxiety, and lower H-Y stage were at increased risk for DDS. The occurrence of DDS may be related to the decrease in the average DAT uptake of the caudate and putamen.


Asunto(s)
Trastornos Disruptivos, del Control de Impulso y de la Conducta , Enfermedad de Parkinson , Humanos , Dopamina , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/epidemiología , Estudios Retrospectivos , Calidad de Vida , Síndrome
14.
Sensors (Basel) ; 23(21)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37960390

RESUMEN

The direction-of-arrival (DOA) estimation is predominantly influenced by the antenna's aperture size. However, space constraints on flight platforms often necessitate the use of antennas with smaller apertures and fewer array elements. This inevitably imposes limitations on the DOA estimation's resolution and degrees of freedom. To address these precision constraints, we introduce an accurate DOA estimation method based on spatial synthetic aperture model. This method adopts a two-stage strategy to ensure both efficiency and precision in DOA estimation. Initially, the orthogonal matching pursuit (OMP) reconstruction algorithm processes the original aperture data, providing a rough estimate of target angles that guides the aircraft's flight direction. Subsequently, the early estimations merge with the aircraft's motion space samples, forming equivalent spatially synthesized array samples. The refined angle estimation then employs the OMP-RELAX algorithm. Moreover, with the off-grid issue in mind, we devise an estimation method integrating Bayesian parameter estimation with dictionary sequence refinement. The proposed technique harnesses the spatial synthetic aperture for pinpoint estimation, effectively addressing the challenges of atomic orthogonality and angular off-grid on estimation accuracy. Importantly, the efficiency of deploying sparse reconstruction for angle estimation is bolstered by our phased strategy, eliminating the necessity for fine grid analysis across the entire observation scene. Moreover, the poor estimation accuracy caused by coherent source targets and angular-flickering targets is improved by sparse reconstruction. Through simulation and experiment, we affirm the proposed method's efficacy in angle estimation. The results indicate that target angle estimation errors are limited to within 1°. Furthermore, we assess the impact of variables such as target state, heading angle, spatial sampling points, and target distance on the estimation accuracy of our method, showcasing its resilience and adaptability.

15.
Aesthetic Plast Surg ; 47(5): 1859-1869, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37145320

RESUMEN

BACKGROUND: Several types of surgeries have been used in the treatment of congenital ptosis, but the optimal methods and materials for this treatment are unknown. PURPOSE: The study aims to evaluate the comparative effectiveness and safety of various surgical methods and materials for treatment of congenital ptosis. METHODS: We performed comprehensive searches of five databases, two clinical trial registries and one gray literature database from inception to January 2022 for related trials to include in this study. Meta-analysis was performed to evaluate the effect of surgical methods and materials on the primary outcomes: margin reflex distance 1 (MRD1), palpebral fissure height (PFH), and degree of lagophthalmos; and secondary outcomes: undercorrection, entropion, corneal epithelial defects, wound dehiscence, recurrence, infection, and cosmetic outcomes. RESULTS: A total of 14 trials evaluating 909 eyes of 657 patients were included in our study. Compared with the levator plication, the frontalis sling significantly increased the MRD1 (MD = - 1.21; 95% CI [- 1.69, - 0.73]), and the levator resection significantly increased the PFH (MD = 1.30; 95% CI [0.27, 2.33]). For the frontalis sling surgical patterns, the fox pentagon was significantly better than the double triangle at improving the degree of lagophthalmos (MD = 0.70; 95% CI [0.32, 1.08]), while the opened pattern provided statistically better cosmetic outcome than the closed frontalis sling. Analysis of surgical material showed that absorbable sutures significantly increased the MRD1 (MD = 1.16; 95% CI [0.60, 1.72]) compared to non-absorbable sutures when used in levator plication; frontalis sling surgeries performed with silicon rods significantly increased the PFH (MD = 0.88; 95% CI [0.29, 1.47]) compared to those performed with Gore-Tex strips, while autogenous fascia lata provided statistically better aesthetic outcome for lid height symmetry and contour. CONCLUSION: Different surgical methods and materials appear to affect different aspects of the congenital ptosis treatment outcome. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Blefaroplastia , Blefaroptosis , Lagoftalmos , Humanos , Blefaroplastia/métodos , Estudios Retrospectivos , Músculos Oculomotores/cirugía , Ensayos Clínicos Controlados Aleatorios como Asunto , Blefaroptosis/cirugía , Blefaroptosis/congénito , Párpados/cirugía , Resultado del Tratamiento
16.
J Surg Orthop Adv ; 32(1): 17-22, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37185072

RESUMEN

The purpose of the study was to (1) assess the prevalence of comorbidities and (2) compare demographics of surgically and non-surgically treated distal humerus fracture patients. Retrospective review of data from a national database was performed. The primary outcome was comorbidities; the secondary outcome was demographic trends between treatment groups. Distal humerus fractures are associated with cerebrovascular disease, dementia, diabetes mellitus, heart disease, hyperlipidemia, hypertension, hypothyroidism, kidney disease, liver disease, and lung disease. Those undergoing surgery are more likely to be obese, under the age of 40 years, female, Medicare recipients with fewer comorbidities, who reside in a rural setting, and who seek care at urban/teaching hospitals within the Southern United States. They are also more likely to have a shorter hospital stay, to be discharged to home, and to have improved survival. (Journal of Surgical Orthopaedic Advances 32(1):017-022, 2023).


Asunto(s)
Fracturas Óseas , Fracturas Humerales Distales , Anciano , Humanos , Adulto , Femenino , Estados Unidos/epidemiología , Medicare , Fracturas Óseas/cirugía , Comorbilidad , Húmero , Demografía , Estudios Retrospectivos , Resultado del Tratamiento
17.
Angew Chem Int Ed Engl ; 62(46): e202312692, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37747050

RESUMEN

The precisely modulated synthesis of programmable light-emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene-based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities and efficiencies than the tetraphenylethylene monomer and can be classified as highly efficient and precisely modulated intramolecular aggregation-induced electrochemiluminescence (PI-AIECL) systems. The best-performing system (SD) shows a high ECL cathodic efficiency exceeding that of the benchmark tris(2,2'-bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six-fold. The electrochemical characterization of these architectures in an organic solvent provides deeper mechanistic insights, revealing that SD features the lowest electrochemical band gap. Density functional theory calculations indicate that the band gap of the guest ligand in the SD structure is the smallest and most closely matched to that of the host scaffold. Finally, the SD system is used to realize ECL-based cysteine detection (detection limit=14.4 nM) in real samples. Thus, this study not only provides a precisely modulated supramolecular strategy allowing chromophores to be controllably regulated on a molecular scale, but also inspires the programmable synthesis of high-performance aggregation-induced electrochemiluminescence emitters.

18.
J Biol Chem ; 296: 100617, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33811860

RESUMEN

Osteoporosis results from an imbalance between bone formation and bone resorption. Traditional drugs for treating osteoporosis are associated with serious side effects, and thus, new treatment methods are required. This study investigated the role of differentially expressed microRNAs during osteoclast differentiation and osteoclast activity during osteoarthritis as well as the associated underlying mechanisms. We used a microarray to screen microRNAs that decreased in the process of osteoclast differentiation and verified miR-21-5p to decrease significantly using RT-qPCR. In follow-up experiments, we found that miR-21-5p targets SKP2 to regulate osteoclast differentiation. In vivo, ovariectomized mice were used to simulate perimenopausal osteoporosis induced by estrogen deficiency, and miR-21-5p treatment inhibited bone resorption and maintained bone cortex and trabecular structure. These results suggest that miR-21-5p is a new therapeutic target for osteoporosis.


Asunto(s)
Diferenciación Celular , Modelos Animales de Enfermedad , MicroARNs/genética , Osteoclastos/citología , Osteogénesis , Osteoporosis/patología , Proteínas Quinasas Asociadas a Fase-S/metabolismo , Animales , Femenino , Ratones , Osteoclastos/metabolismo , Osteoporosis/genética , Osteoporosis/metabolismo , Células RAW 264.7 , Proteínas Quinasas Asociadas a Fase-S/genética
19.
Small ; 18(26): e2202167, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35638477

RESUMEN

Dye aggregates have attracted a great deal of attention due to their widespread applications in organic light-emitting devices, light-harvesting systems, etc. However, the strategies to precisely control chromophores with specific spatial arrangements still remain a great challenge. In this work, a series of double- and triple-decker supramolecular complexes are successfully constructed by coordination-driven self-assembly of carefully designed shape-complementary ligands, one claw-like tetraphenylethylene (TPE)-based host ligand and three tetratopic or ditopic guest ligands. The spatial configurations of these assemblies (one double-decker and three "S-shaped" or "X-shaped" triple-decker structures) depend on the angles of these TPE-derived ligands. Notably, the three triple-decker structures are geometric isomers. Furthermore, photophysical studies show that these complexes exhibit different ratios of radiative (kr ) and non-radiative (knr ) rate constant due to the different spatial arrangements of TPE moieties. This study provides not only a unique strategy for the construction of multi-stacks with specific spatial arrangement, but also a promising platform for investigating the aggregation behavior of fluorescent chromophores.


Asunto(s)
Ligandos , Isomerismo
20.
Opt Express ; 30(20): 35311-35324, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36258485

RESUMEN

In this paper, we present a quasi-optically coupled 600-GHz high-temperature superconducting (HTS) sub-harmonic mixer for communication and sensing applications. The mixer features an innovative double-Y-type slot integrated lens antenna, which can efficiently couple the radio frequency (RF) and local oscillator (LO) signals with a small frequency ratio by exciting the half-wave and full-wave resonant current modes on the slot, respectively. Considering the low impedance characteristics of HTS Josephson junctions, a coplanar-waveguide stepped impedance transformer is utilized for minimizing the mismatching loss. A cascaded filter network is designed to prevent the high-frequency signal leakage at both bands while coupling the intermediate-frequency (IF) signal output efficiently. Based on this antenna design and an established HTS step-edge junction technology, a 600-GHz mixer prototype was designed, fabricated and measured, which was compared with the simulation results. The achieved conversion gain and noise temperature are the best performance specs as reported to date for HTS harmonic mixers at comparable frequencies and operating temperatures.

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