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AIM: To analyse factors associated with cognitive frailty among older chronic heart failure patients in China. DESIGN: A cross-sectional design. METHODS: Between August 2021 and November 2022, a total of 421 chronic heart failure patients (age ≥60 years) were randomly selected from the cardiology department of the affiliated hospital of Zunyi Medical University. The FRAIL scale, Mini-Mental State Examination, 15-item Geriatric Depression Scale, Social Support Rating Scale, Short-form Mini Nutritional Assessment and Pittsburgh Sleep Quality Index were utilized for measurement and evaluation. The demographic and clinical characteristics of patients were collected. To select initial variables, the Least Absolute Shrinkage Selection Operator was applied, and then logistic regression analysis was used to confirm associating factors. RESULTS: Among 421 elderly people with chronic heart failure, 83 cases (19.7%) showed cognitive frailty. Of 31 variables, seven were selected by Least Absolute Shrinkage Selection Operator regression. Finally, multivariate logistic regression revealed that the age, monthly salary, drinking, NYHA classification, length of hospital stay, depression and malnutrition risk/malnutrition were independently associated with cognitive frailty. CONCLUSION: The high proportion of cognitive frailty in older people with chronic heart failure should be concerned. Additionally, in the setting of cognitive frailty, efforts to diagnose it and develop interventions to prevent or reverse cognitive frailty status among older chronic heart failure patients are necessary. IMPACT: The findings of our study highlight the necessity to evaluate cognitive frailty in older people with chronic heart failure and provide a new perspective and scientific basis for medical staff to develop individualized and specific interventions to prevent or reverse cognitive frailty status. REPORTING METHOD: This study has been reported in compliance with STROBE reporting guidelines for cross-sectional studies. PATIENT OR PUBLIC CONTRIBUTION: No Patient or Public Contribution.
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Daily temperature variations, which tend to exhibit non-constant and non-linear patterns, are often characterized by intra-annual fluctuations that cause severe and frequent extreme temperature events that have an enormous impact on agricultural production. However, the quantitative relationship between intra-annual temperature fluctuations and extreme agricultural temperatures remains unclear. We aimed to investigate intra-annual temperature fluctuation changes based on daily meteorological data in nine agricultural regions across China from 1960 to 2022 and quantify the impact of temperature fluctuations on extreme agricultural temperatures during crop growth periods. Moreover, an attribution analysis of intra-annual temperature fluctuations was performed using climate indicators. Main results showed: (1) intra-annual temperature fluctuations in each region exhibited a certain decrease, and the spatial distribution showed a significant decreasing trend from north to south. (2) Intra-annual temperature fluctuations have moderately exacerbated extreme agricultural hot and cold events during growth periods, which have brought serious challenges to agriculture owing to advances in phenology and unsynchronized rain heat compared to climate warming. The proportion of positive correlations between temperature fluctuations and extreme temperatures was much larger than that of the negative correlations in nearly all of China (percentage of stations: 20.5 %), and the negative correlation was concentrated only in southern China (percentage of stations: 3.7 %). (3) Hydrothermal coupling and elevation moderately affected intra-annual temperature fluctuations. Average temperature, relative humidity, and elevation had negative correlations with intra-annual temperature fluctuations, the correlation coefficients (R) were - 0.62, -0.42 and - 0.12, respectively; however, reference crop evapotranspiration (ET0) exhibited a positive correlation (R: 0.29), and all reached highly significant levels (P < 0.01). Climate indicators mainly affected intra-annual temperature fluctuations in eastern China. Specifically, the El Niño-Southern Oscillation (ENSO), unstable Asia Polar Vortex, and increased Western Pacific Subtropical High have enhanced temperature fluctuations. The deepened East Asian Trough and Arctic Oscillation of the negative phase weakened the intra-annual temperature fluctuations. This investigation highlights the crucial function of temperature fluctuation in intensifying extreme temperature occurrences and provides a more reasonable scientific foundation for extreme event prediction and agricultural planning.
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Recently a new family of partially coherent fields incorporating generalized inseparable cross-coupled phases named generalized higher-order twisted partially coherent beams (GHTPCBs) have been introduced. The twist factor u is a key parameter that not only quantifies the strength of the generalized cross-coupled phase for a given order, but also determines the amount of the concomitant orbital angular momentum (OAM). In this paper, we propose a simple and reliable method to measure the factor u using a two-pinhole mask. Without need of complicated optical system, it only requires to capture the far-field diffraction intensity distribution of the GHTPCB passing through the mask. By analyzing the Fourier spectrum of the intensity distribution, the value of twist factor can be derived nearly in real time. The influence of the separation distance between two pinholes and the pinholes' diameter and position on the measurement accuracy are thoroughly studied both in theory and experiment. The experimental results agree well with the theoretical results. Our methodology can also be extended to measure the sole factor of similar position dependent phases such as the topological charge of a vortex phase.
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Optical information transmission is vital in modern optics and photonics due to its concurrent and multi-dimensional nature, leading to tremendous applications such as optical microscopy, holography, and optical sensing. Conventional optical information transmission technologies suffer from bulky optical setup and information loss/crosstalk when meeting scatterers or obstacles in the light path. Here, we theoretically propose and experimentally realize the simultaneous manipulation of the coherence lengths and coherence structures of the light beams with the disordered metasurfaces. The ultra-robust optical information transmission and self-reconstruction can be realized by the generated partially coherent beam with modulated coherence structure even 93% of light is recklessly obstructed during light transmission, which brings new light to robust optical information transmission with a single metasurface. Our method provides a generic principle for the generalized coherence manipulation on the photonic platform and displays a variety of functionalities advancing capabilities in optical information transmission such as meta-holography and imaging in disordered and perturbative media.
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BACKGROUND: The surgical approach for patients with Siewert type II AEG remains controversial. Several studies have described a new laparoscopic radical resection approach of Siewert type II AEG through the left diaphragm. However, the technical safety and feasibility of the new surgical approach compared with the transhiatal approach have not yet been tested. STUDY DESIGN: We retrospectively reviewed patients with AEG who underwent TSLG and LTH operations in the Guangdong Provincial Hospital of Chinese Medicine between January 2017 and April 2021. Histologically confirmed AEG and D2 lymphadenectomy with curative R0 patients were included, and patients with Siewert I/III AEG or distant metastasis were excluded. Blood loss, the amount of harvested lymph node, and complications related to surgery were evaluated. RESULTS: A total of 99 patients with Siewert type II AEG were analyzed, 44 in the TSLG group and 55 in the LTH group. There was no difference in clinicopathological features between the two groups. The more harvested lymph node (23.33 ± 11.41 vs. 32.18 ± 12.85, p < 0.01), lower mediastinal lymph node (1.07 ± 2.08 vs. 3.25 ± 3.31, p < 0.01), and longer proximal margin length (3.08 ± 1.19 vs. 4.47 ± 0.95 cm, p < 0.01) were observed in the TSLG group. The rate of cure (R0 gastrectomy) in the TSLG group was higher than that in the LTH group (100% vs. 89.09%, p = 0.03). CONCLUSION: The TSLG approach is associated with improved surgical views, simplified lymphatic dissection in the inferior mediastinum, and more reliable margins. TSLG surgery may be an effective addition to LTH surgery, particularly when lower mediastinal lymph node metastases are suspected.
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Adenocarcinoma , Neoplasias Esofágicas , Laparoscopia , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Adenocarcinoma/patologia , Junção Esofagogástrica/cirurgia , Junção Esofagogástrica/patologia , Excisão de Linfonodo , Gastrectomia , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologiaRESUMO
The excessive usage of veterinary antibiotics has raised significant concerns regarding their environmental hazard and agricultural impact when entering surface water and soil. Animal waste serves as a primary source of organic fertilizer for intensive large-scale agricultural cultivation, including the widely utilized medicinal and edible plant, Polygonatum cyrtonem. In this study, we employed a novel plant stress tissue culture technology to investigate the toxic effects of tetracycline hydrochloride (TCH) and sulfadiazine (SDZ) on P. cyrtonema. TCH and SDZ exhibited varying degrees of influence on plant growth, photosynthesis, and the reactive oxygen species (ROS) scavenging system. Flavonoid levels increased following exposure to TCH and SDZ. The biosynthesis and signaling pathways of the growth hormones auxin and gibberellic acid were suppressed by both antibiotics, while the salicylic acid-mediated plant stress response was specifically induced in the case of SDZ. Overall, the study unveiled both common and unique responses at physiological, biochemical, and molecular levels in P. cyrtonema following exposure to two distinct types of antibiotics, providing a foundational framework for comprehensively elucidating the precise toxic effects of antibiotics and the versatile adaptive mechanisms in plants.
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Antibacterianos , Polygonatum , Antibacterianos/toxicidade , Fotossíntese , Reguladores de Crescimento de Plantas , Polygonatum/química , Sulfadiazina , Tetraciclina , TranscriptomaRESUMO
Land surface temperature (LST) is a crucial parameter in the circulation of water, exchange of land-atmosphere energy, and turbulence. Currently, most LST products rely heavily on thermal infrared remote sensing, which is susceptible to cloud and rain interference, leading to inferior temporal continuity. Microwave remote sensing has the advantage of being available "all-weather" due to strong penetration capability, which provides the possibility to simulate time-continuous LST data. In addition, the continuous increase in high-density station observations (>10,000 stations) provides reliable measured data for the remote sensing monitoring of LST in China. This study aims to adopt the "Earth big data" generated from high-density station observation and microwave remote sensing data to monitor LST based on deep learning (U-Net family) for the first time. Given the significant spatial and temporal variability of LST and its sensitivity to various factors according to radiation transmission equations, this study incorporated climatic, anthropogenic, geographical, and vegetation datasets to facilitate a multi-source data fusion approach for LST estimation. The results showed that the U-Net++ model with modified skip connections better minimized the semantic discrepancy between the feature maps of the encoder and decoder subnetworks for 0.1° daily LST mapping across China than the U-Net and U2-Net deep learning models. The accuracy of the LST simulation exhibited favorable outcomes in the spatial and temporal dimensions. The station density met the requirements of monitoring air-ground integration monitoring in China. Additionally, the temporal change in the simulation accuracy fluctuated in a W-shape owing to the limited simulation capability of deep learning in extreme scenarios. Anthropogenic factors had the largest influence on LST changes in China, followed by climate, geography, and vegetation. This study highlighted the application of deep learning in remote sensing monitoring against the background of "big data" and provided a scientific foundation for the response of climate change to human activities, ecological environmental protection, and sustainable social and economic development.
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We investigate the second-order statistics of a twisted Hermite-Gaussian correlated Schell-model (THGCSM) beam propagation in turbulent atmosphere, including the spectral density, degree of coherence (DOC), root mean square (r.m.s.) beam wander and orbital angular momentum (OAM) flux density. Our results reveal that the atmospheric turbulence and the twist phase play a role in preventing the beam splitting during beam propagation. However, the two factors have opposite effects on the evolution of the DOC. The twist phase preserves the DOC profile invariant on propagation, whereas the turbulence degenerates the DOC. In addition, the influences of the beam parameters and the turbulence on the beam wander are also studied through numerical examples, which show that the beam wander can be reduced by modulating the initial parameters of the beam. Further, the behavior of the z-component OAM flux density in free space and in atmosphere is thoroughly examined. We show that the direction of the OAM flux density without the twist phase will be suddenly inversed at each point across the beam section in the turbulence. This inversion only depends on the initial beam width and the turbulence strength, and in turn, it offers an effective protocol to determine the turbulence strength by measuring the propagation distance where the direction of OAM flux density is inversed.
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To investigate the influencing factors of lower limb amputation in patients with diabetic foot ulcers. Patients with diabetic foot ulcers who were hospitalised in a tertiary general hospital in Guizhou Province from January 2019 to March 2022 were retrospectively collected. Sociological information of the general population, comorbidities, laboratory-related indicators, and information on the specialty situation, using univariate analysis and multifactor analysis, compared the influencing factors of amputation and non-amputee patients. A total of 205 patients with diabetic foot and 69 ampute patients (33.7%) were enrolled. The univariate analysis found that the decrease in HDL cholesterol levels was associated with the occurrence of lower extremity amputation, and logistic stepwise regression analysis showed that HDL-C was inversely correlated with the amputation rate of patients with diabetic foot ulcers, and the risk of amputation at low levels of HDL-C was 2.452 times higher than that of high-level HDL-C (95% CI: 1.105-5.846). Decreased HDL cholesterol levels are an independent predictor of amputation in patients with diabetic foot ulcers.
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Diabetes Mellitus , Pé Diabético , Úlcera do Pé , Humanos , Pé Diabético/cirurgia , Pé Diabético/epidemiologia , Estudos Retrospectivos , HDL-Colesterol , Amputação Cirúrgica , Extremidade Inferior/cirurgia , Fatores de RiscoRESUMO
BACKGROUND: Salinization is major abiotic stress limiting cotton production. Melatonin (MT) has been implicated in salt stress tolerance in multiple crops including upland cotton. Here, we explored the transcriptomic and metabolomic response of a salt-tolerant self-bred high-yielding cotton line SDS-01, which was exogenously sprayed with four MT concentrations (50, 100, 200, and 500 µM). RESULTS: Here we found that MT improves plant biomass and growth under salt stress. The combined transcriptome sequencing and metabolome profiling approach revealed that photosynthetic efficiency is improved by increasing the expressions of chlorophyll metabolism and antenna proteins in MT-treated seedlings. Additionally, linoleic acid and flavonoid biosynthesis were improved after MT treatment. The Na+/K+ homeostasis-related genes were increasingly expressed in salt-stressed seedlings treated with MT as compared to the ones experiencing only salt stress. Melatonin treatment activated a cascade of plant-hormone signal transduction and reactive oxygen scavenging genes to alleviate the detrimental effects of salt stress. The global metabolome profile revealed an increased accumulation of flavonoids, organic acids, amino acids and derivatives, saccharides, and phenolic acids in MT-treated seedlings. Interestingly, N, N'-Diferuloylputrescine a known antioxidative compound was highly accumulated after MT treatment. CONCLUSION: Collectively, our study concludes that MT is a salt stress regulator in upland cotton and alleviates salt-stress effects by modulating the expressions of photosynthesis (and related pathways), flavonoid, ROS scavenging, hormone signaling, linoleic acid metabolism, and ion homeostasis-related genes.
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Gossypium , Melatonina , Gossypium/genética , Tolerância ao Sal/genética , Plântula/genética , Transcriptoma , Melatonina/farmacologia , Melhoramento Vegetal , Metaboloma , Flavonoides , Ácidos LinoleicosRESUMO
To solve the problem that the channel conditions in asymmetric cooperative FSO communication systems are not fully utilized, and the data reliability deteriorates due to high-order modulation, we proposed a layered modulation, joint physical-layer network coding scheme. In this scheme, we first designate the data priority of the information to be transmitted at the source node. Then, the transmission power of different proportions is allocated to the data based on its priority. Then, the modulated data is sent to each node, and physical-layer network coding is performed on the received data at the relay node. Finally, the relay node sends the encoded information to the destination node, and the destination node recovers the original information using the physical-layer network coding scheme. The simulation results showed that when the average signal-to-noise ratio of the channel was 15 dB, the BER of the cooperative FSO communication system could be reduced to below 10-8. In the strong atmospheric turbulence channel, the cooperative FSO communication system can obtain a signal-to-noise ratio gain of about 1.5 dB. Under strong atmospheric turbulence, this scheme could also improve the average channel capacity performance of a cooperative FSO communication system.
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As an advanced technology, simultaneous wireless information and power transfer (SWIPT), combined with the internet of things (IoT) devices, can effectively extend the online cycle of the terminal. To cope with the fluctuation of energy harvesting by the hybrid access points (H-AP), the energy cooperation base station is introduced to realize the sharing of renewable energy. In this paper, we study the SWIPT-enabled IoT networks with cooperation. Our goal is to maximize the energy efficiency of the system, and at the same time, we need to meet the energy harvesting constraints, user quality of service (QoS) constraints and transmission power constraints. We jointly solve the power allocation, time switching and energy cooperation problems. Because this problem is a nonlinear programming problem, it is difficult to solve directly, so we use the alternating variable method, the iterative algorithm is used to solve the power allocation and time switching problem, and the matching algorithm is used to solve the energy cooperation problem. Simulation results show that the proposed algorithm has obvious advantages in energy efficiency performance compared with the comparison algorithm. At the same time, it is also proved that the introduction of energy cooperation technology can effectively reduce system energy consumption and improve system energy efficiency.
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Background: Diabetic kidney disease (DKD) is the primary cause of end-stage renal disease, raising a considerable burden worldwide. Recognizing novel biomarkers by metabolomics can shed light on new biochemical insight to benefit DKD diagnostics and therapeutics. We hypothesized that serum metabolites can serve as biomarkers in the progression of DKD. Methods: A cross-sectional study of 1,043 plasma metabolites by untargeted LC/MS among 89 participants identified associations between proteinuria severity and metabolites difference. Pathway analysis from differently expressed metabolites was used to determine perturbed metabolism pathways. The results were replicated in an independent, cross-sectional cohort of 83 individuals. Correlation and prediction values were used to examine the association between plasma metabolites level and proteinuria amount. Results: Diabetes, and diabetic kidney disease with different ranges of proteinuria have shown different metabolites patterns. Cysteine and methionine metabolism pathway, and Taurine and hypotaurine metabolism pathway were distinguishable in the existence of DKD in DC (diabetes controls without kidney disease), and DKD with different ranges of proteinuria. Two interesting tetrapeptides (Asn-Met-Cys-Ser and Asn-Cys-Pro-Pro) circulating levels were elevated with the DKD proteinuria progression. Conclusions: These findings underscore that serum metabolomics provide us biochemical perspectives to identify some clinically relevant physiopathologic biomarkers of DKD progression.
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The correction pointed out by Nemes [J. Opt. Soc. Am. A39, 667 (2022)JOAOD60740-323210.1364/JOSAA.435756] to our paper [J. Opt. Soc. Am. A37, 89 (2020)JOAOD60740-323210.1364/JOSAA.37.000089] is welcome. The author claims that the beam propagation factors Mx2, My2 are inadequate to characterize twisted elliptical multi-Gaussian Schell-model (TEMGSM) beams, which are introduced in our paper. Further, the author points out that there are two pairs of independent, normalized invariants to classify the TEMGSM beams. In this reply, we present the numerical example of the normalized intrinsic propagation invariants of the TEMGSM beams.
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The formation of biofilm enables Staphylococcus aureus to resist antibiotics and causes chronic infections. Several compounds of pyrrolomycins are potent antibacterial agents which display inhibition upon staphylococcal biofilms. We designed and synthesized two series of substituted pyrazoles as pyrrolomycin analogues. Compounds 17a, 17d and 17h displayed potent antibacterial activity against various vancomycin-resistant Enterococcus faecalis (VRE) and methicillin-resistant Staphylococcus aureus (MRSA), and 17d showed the most potent activity against MRSA (MIC = 0.0625 µg/mL), vancomycin-intermediate Staphylococcus aureus (VISA) (MIC = 0.0313 µg/mL). Further study indicated that compound 17h could significantly reduce the biofilm formation of MRSA and exhibited promising selectivity. In vitro liver microsomal stability was also evaluated and the results manifested that 17h was metabolically stable in human liver microsomes.
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Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/farmacologia , Biofilmes , Humanos , Testes de Sensibilidade Microbiana , Pirazóis/farmacologia , Staphylococcus , Staphylococcus aureusRESUMO
We introduce a new type of partially coherent vector beam, named the radially polarized twisted partially coherent vortex (RPTPCV) beam. Such a beam carries the twist phase and the vortex phase simultaneously, and the initial state of polarization (SOP) is radially polarized. On the basis of the pseudo-modal expansion and fast Fourier transform algorithm, the second-order statistics such as the spectral density, the degree of polarization (DOP) and the SOP, propagation through a paraxial ABCD optical system are investigated in detail through numerical examples. The results reveal that the propagation properties of the RPTPCV beam closely depends on the handedness of the twist phase and the vortex phase. When the handedness of the two phases is same, the beam profile is easier to remain a dark hollow shape and the beam spot rotates faster during propagation, compared to the partially coherent vortex beam or the RPTPCV beam with the opposite handedness of the two phases. In addition, the same handedness of two phases resists the coherence induced de-polarization of the beam upon propagation, and the SOP is also closely related to the handedness, topological charge of the vortex phase and the twist factor of the twist phase, providing an efficient way to modulate the beam's DOP and SOP in the output plane. Moreover, we establish an experiment setup to generate the RPTPCV beam. The average spectral density and the polarization properties are examined in the experiment. The experimental results agree reasonable well with the theoretical predictions. Our results will be useful for particle manipulating, free-space optical communications, and polarization lidar systems.
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Aiming at the poor bit error rate (BER) performance of spinal code in free-space optical communication, a polar-UEP (unequal error protection) spinal concatenated coding scheme for free-space optical communication is proposed. This work combines the unequal error protection characteristics of spinal codes and the construction characteristics of polar codes, using bit sorting and interleaving, to give the best protection of the polar code's information bits, and the bits that are prone to error. Simulation results show that the bit error rate performance of the more important bits and the less important bits of the polar-UEP spinal concatenated code is better than that of the spinal code. When the turbulence intensity is 0.1, compared with the fixed rate coding scheme such as the polar code, the concatenated code generates 0.7 dB-1.2 dB gain at a BER of 10-4. Besides, its BER under different turbulence intensity is lower than that of the spinal code and polar code, and this provides a solution for the efficient application of the spinal code in free-space optical communication.
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Algoritmos , Simulação por ComputadorRESUMO
Sepsis is a heterogeneous syndrome induced by infection and results in high mortality. Even though more than 100 biomarkers for sepsis prognosis were evaluated, prediction of patient outcomes in sepsis continues to be driven by clinical signs because of unsatisfactory specificity and sensitivity of these biomarkers. This study aimed to elucidate the key candidate genes involved in sepsis response and explore their downstream effects based on weighted gene co-expression network analysis (WGCNA). The dataset GSE63042 with sepsis outcome information was obtained from the Gene Expression Omnibus (GEO) database and then consensus WGCNA was conducted. We identified the hub gene SDF4 (stromal cell derived factor 4) from the M6 module, which was significantly associated with mortality. Subsequently, two datasets (GSE54514 and E-MTAB-4421) and cohort validation (n=89) were performed. Logistic regression analysis was used to build a prediction model and the combined score resulting in a satisfactory prognosis value (area under the ROC curve=0.908). The model was subsequently tested by another sepsis cohort (n=70, ROC= 0.925). We next demonstrated that endoplasmic reticulum (ER) stress tended to be more severe in patients PBMCs with negative outcomes compared to those with positive outcomes and SDF4 was related to this phenomenon. In addition, our results indicated that adenovirus-mediated Sdf4 overexpression attenuated ER stress in cecal ligation and puncture (CLP) mice lung. In summary, our study indicates that incorporation of SDF4 can improve clinical parameters predictive value for the prognosis of sepsis, and decreased expression levels of SDF4 contributes to excessive ER stress, which is associated with worsened outcomes, whereas overexpression of SDF4 attenuated such activation.
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Biomarcadores , Proteínas de Ligação ao Cálcio/metabolismo , Estresse do Retículo Endoplasmático , Glicoproteínas/metabolismo , Sepse/metabolismo , Sepse/mortalidade , Proteínas de Ligação ao Cálcio/sangue , Proteínas de Ligação ao Cálcio/genética , Biologia Computacional , Bases de Dados Genéticas , Suscetibilidade a Doenças , Imunofluorescência , Perfilação da Expressão Gênica , Glicoproteínas/sangue , Glicoproteínas/genética , Humanos , Imuno-Histoquímica , Prognóstico , Curva ROC , Sepse/diagnóstico , Sepse/etiologia , TranscriptomaRESUMO
Twisted Laguerre-Gaussian Schell model (TLGSM) beams are a novel type of partially coherent beams, which carry the twist phase and the vortex phase simultaneously. In this paper, the self-reconstruction (SR) of the TLGSM beam partially blocked by an opaque obstacle and propagating through a thin lens focusing system is studied in detail. Implementing the pseudo-mode expansion method, we represent the TLGSM beam as a superposition of spatially coherent modes, which is applicable for calculating the cross spectral density (CSD) and spectral degree of coherence (SDOC) of such a beam using the Fourier transform. The numerical results reveal that the twist parameter, a measure of the strength of a twist phase, determines the characteristics of the SR. In the case of the topological charge of the vortex is positive, the SR capability of spectral density is significantly improved with the increase of the twist parameter. The physical mechanism behind these phenomena is analyzed in detail from the point view of mode expansion. Further, the dependence of the side ring intensity and SR capability of the SDOC on the twist parameter are also investigated. It is found that the SR capability and side ring intensity of the SDOC are simultaneously enhanced for a large twist parameter, providing an efficient way to determine the number of topological charge. Our study results may find application in communication and information recovery applications.
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We introduce a new kind of partially coherent source whose cross-spectral density (CSD) function is described as the incoherent superposition of elliptical twisted Gaussian Schell-model sources with different beam widths and transverse coherence widths, named twisted elliptical multi-Gaussian Schell-model (TEMGSM) beams. Analytical expression for the CSD function propagating through a paraxial ABCD optical system is derived with the help of the generalized Collins formula. Our results show that the TEMGSM beam is capable of generating a flat-topped elliptical beam profile in the far field, and the beam spot during propagation exhibits clockwise/anti-clockwise rotation with respect to its propagation axis. In addition, the analytical expressions for the orbital angular momentum (OAM) and the propagation factor are also derived by means of the Wigner distribution function. The influences of the twisted factor and the beam index on the OAM and the propagation factor are studied and discussed in detail.