Radiation dosimeters displaying conspicuous response of irradiance are highly desirable, owing to the growing demand of monitoring high-energy radiation and environmental exposure. Herein, we present ...a case of dosimetry based on a discrete nanocluster, Th
(OH)
(O)
(H
O)
(TPC)
(HCOO)
∙4DMF∙H
O (Th-SINAP-100), by judiciously incorporating heavy Th
polynuclear centers as radiation attenuator and organic linkers as photo-responsive sensor. Interestingly, dual-module photochromic transitions upon multiple external stimuli including UV, β-ray, and γ-ray are integrated into this single material. The striking color change, and more significantly, the visible color transition of luminescence in response to accumulating radiation dose allow an on-site quantitative platform for naked-eye detection of ionization radiations over a broad range (1-80 kGy). Single crystal X-ray diffraction and density functional theory calculations reveal that the dual-module photochromism can be attributed to the π(TPC) → π*(TPC) intermolecular charge transfer driven by enhanced π-π stacking interaction between the adjacent TPC moieties upon irradiation.
Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder that potentially threatened people's cardiovascular system. As an alternative to polysomnography for OSA detection, ...ECG-based methods have been developed for several years. However, previous work is focused on feature engineering, which is highly dependent on the prior knowledge of human experts and maybe subjective. Moreover, feature engineering also highlights the prominent shortcoming of current learning algorithms that the features are unable to extracted and organized from the data. In this study, we proposed a method to detect OSA based on deep neural network and Hidden Markov model (HMM) using single-lead ECG signal. The method utilized sparse auto-encoder to learn features, which belongs to unsupervised learning that only requires unlabeled ECG signals. Two types classifiers (SVM and ANN) are used to classify the features extracted from the sparse auto-encoder. Considering the temporal dependency, HMM was adopted to improve the classification accuracy. Finally, a decision fusion method is adopted to improve the classification performance. About 85% classification accuracy is achieved in the per-segment OSA detection, and the sensitivity is up to 88.9%. Based on the results of per-segment OSA detection, we perfectly separate the OSA recording from normal with accuracy of 100%. Experimental results demonstrated that our proposed method is reliable for OSA detection.
Long-distance entanglement distribution is essential for both foundational tests of quantum physics and scalable quantum networks. Owing to channel loss, however, the previously achieved distance was ...limited to ~100 kilometers. Here we demonstrate satellite-based distribution of entangled photon pairs to two locations separated by 1203 kilometers on Earth, through two satellite-to-ground downlinks with a summed length varying from 1600 to 2400 kilometers. We observed a survival of two-photon entanglement and a violation of Bell inequality by 2.37 ± 0.09 under strict Einstein locality conditions. The obtained effective link efficiency is orders of magnitude higher than that of the direct bidirectional transmission of the two photons through telecommunication fibers.
Transition metal oxides (TMOs) and actinide ones (AnOs) have been widely applied in catalytic reactions due to their excellent physicochemical properties. However, the reaction pathway and mechanism, ...especially involving TM–An heterometallic centers, remain underexplored. In this respect, relativistic density functional theory (DFT) was used to examine uranium-doped zinc, copper, and nickel oxides for their catalytic activity toward the conversion of furfural to furfuryl alcohol. A comparison was made with their undoped TMOs. It was found that the three TMOs were capable of catalyzing the reaction, where the free energies of adsorption, hydrogenation, and desorption fell between −33.93 and 45.00 kJ/mol. The uranium doping extremely strengthened the adsorption of CuO-U and NiO-U toward furfural, making hydrogenation or desorption much harder. Intriguingly, ZnO-U showed the best catalytic performance among all six catalyst candidates, as its three reaction energies were very small (−10.54–8.12 kJ/mol). The reaction process and mechanism were further addressed in terms of the geometrical, bonding, charge, and electronic properties.
In terms of spent nuclear fuel reprocessing, molecular dynamics (MD) and density functional theory (DFT) calculations reveal two driving-force models for selective extraction and separation. In ...contrast to previous reported extractants that fulfilled Model I, we have discovered that the operation of hexaoctyl-nitrilotriacetamide towards La3+/Lu3+ conforms to Model II. It offers the first example and potentially introduces a novel approach to design selective extractants.
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•Multi-scale systems are explored by molecular dynamics (MD) and DFT methods.•Dynamic behaviors that NTAamide extracts and separates Ln ions are delineated.•Dominant reactions in the process are screened from 108 possible ones.•The origin of selectively separating La3+ over Lu3+ is revealed by two driving-force models.•Strategies are proposed to design and optimize extractant with high selectivity.
Extraction and separation technology forms an essential component of contemporary spent nuclear fuel reprocessing. Comprehending the underlying factors that drive extractant selectivity holds immense importance in crafting and advancing new extractants with optimal and desired performance. However, the majority of previous studies predominantly concentrated on organometallic complexes generated, while overlooked the entirety of the extraction process. In this study, we employ molecular dynamics (MD), extended tight-binding (xTB), and density functional theory (DFT) methods to comprehensively investigate the entire reaction process, with particular attention to overlooked aspects. Our findings reveal that the selectivity preference in the extraction reaction originates from the competition involved in the formation of metal complexes in both the aqueous and organic phases. Addressing the previously neglected aspects is crucial for providing clear guidance to enhance extraction selectivity. In the process, we have developed two driving force models and explained the origin of extraction selectivity. Model I is propelled by distinctions among organometallic complexes, whereas Model II is influenced by their similarities. Little is known about Model II since reported extractants fulfill Model I. Notably, we have discovered that the extraction and separation of La3+/Lu3+ using hexaocactyl-nitrilotriacetamide conforms to Model II, marking the first example and potentially introducing a novel approach to design selective extractants.
Excessive blood loss in total joint arthroplasty (TJA) usually leads to an allogenic blood transfusion, which may cause adverse outcomes, prolonged length of hospitalization, and increased costs. The ...purpose of this study was to determine the incidence and risk factors for intraoperative and postoperative allogenic transfusion in patients undergoing primary unilateral total knee and hip arthroplasty (TKA and THA).
We conducted a retrospective study and enrolled consecutive patients undergoing primary unilateral TKA and THA at our institution between January 2010 and July 2014 (n = 1534). Information about allogenic transfusion was collected from medical records to determine the incidence. We performed univariate analysis and multivariate logistic regression analysis to identify the independent risk factors.
Total, intraoperative, and postoperative transfusion rates were 17.9%, 7.9%, and 11.3%, respectively. The preoperative lower level of hemoglobin (Hb) (P < 0.001) and increased amount of intraoperative blood loss (P < 0.001) were independently associated with transfusion in TKA. The independent risk factors for transfusion in THA were female (P = 0.023), preoperative lower Hb level (P < 0.001), prolonged operation time (P < 0.001), and increased intraoperative blood loss (P < 0.001).
Given the high prevalence and potential risk of transfusion in TJA, interventions for identified risk factors should be used during the perioperative period.
The design of multimetal catalysts holds immense significance for efficient CO2 capture and its conversion into economically valuable chemicals. Herein, heterobimetallic catalysts (MiMo)L were ...exploited for the CO2 reduction reactions (CO2RR) using relativistic density functional theory (DFT). The octadentate Pacman-like polypyrrolic ligand (H4L) accommodates two metal ions (Mo, W, Nd, and U) inside (Mi) and outside (Mo) its month, rendering a weak bimetal coupling-assisted MN4 catalytically active site. Adsorption reactions have access to energetically stable coordination modes of –OCO, –OOC, and –(OCO)2, where the donor atom(s) are marked in bold. Among all of the species, (UiMoo)L releases the most energy. Along CO2RR, it favors to produce CO. The high-efficiency CO2 reduction is attributed to the size matching of U with the ligand mouth and the effective manipulation of the electron density of both ligand and bimetals. The mechanism in which heterobimetals synergetically capture and reduce CO2 has been postulated. This establishes a reference in elaborating on the complicated heterogeneous catalysis.
Background
Syncope is a perplexing challenge that often receives thorough evaluation, yet the diagnosis remains unclear. Usually, the emergency department is the first point at which patients present ...with syncope. However, diverse medical factors, including low diagnostic rates and inconsistent management by doctors, add to healthcare costs and delay diagnosis for syncope patients.
Methods
Patients who had been to the emergency department at least once but were not given a clear diagnosis of syncope were recruited into our study at the time they visited syncope clinic staffed by a multidisciplinary team. Complete medical histories and clinical examinations were conducted by both experienced cardiologists and neurologists. If patients were not given a conclusive diagnosis at the syncope clinic on the basis of outpatient examinations, they were admitted for further evaluation.
Results
A total of 209 consecutive patients claiming “syncope” visited the syncope clinic, yet only 167 patients were formally diagnosed with syncope. For these 167 patients, the mean age was 55.93 ± 17.40 years old, and 41.3% were male. The proportions of cardiac syncope, reflex syncope, orthostatic hypotension (OH), and syncope of uncertain etiology were 19.8%, 64.1%, 7.8%, and 8.4%, respectively. The diagnostic rate was 91.6%, and the hospitalization rate was 23.4%. Patients with reflex syncope and OH were younger than patients with cardiac syncope. Cardiac syncope tends to occur more frequently in males, while reflex syncope is more likely in females.
Conclusions
The cooperation of professional cardiologists and neurologists will play an important role in improving diagnostic rates, lowering admission rates, and reducing medical costs.
Tendon derived stem cells (TDSCs) have proven to be effective in tendon repair by secreting paracrine factors, which modulate the function of resident cells and inflammatory process. Exosomes, which ...are secreted from cells to mediate intercellular communication, may be used to treat tendon injuries. Here, we aimed to determine the effects of exosomes from TDSCs (TDSC-Exos) on tendon repair and to explore the underlying mechanism by investigating the role of microRNAs (miRNAs).
TDSC-Exos were isolated from TDSC conditioned medium. In vitro studies were performed to investigate the effects of TDSC-Exos on the proliferation, migration, cytoprotection, collagen production and tendon-specific markers expression in tenocytes. In order to determine the therapeutic effects of TDSC-Exos in vivo, we used a scaffold of photopolymerizable hyaluronic acid (p-HA) loaded with TDSC-Exos (pHA-TDSC-Exos) to treat tendon defects in the rat model. Subsequently, RNA sequencing and bioinformatic analyses were used to screen for enriched miRNAs in TDSC-Exos and predict target genes. The miRNA-target transcript interaction was confirmed by a dual-luciferase reporter assay system. In order to determine the role of candidate miRNA and its target gene in TDSC-Exos-regulated tendon repair, miRNA mimic and inhibitor were transfected into tenocytes to evaluate cell proliferation and migration.
Treatment with TDSC-Exos promoted proliferation, migration, type I collagen production and tendon-specific markers expression in tenocytes, and also protected tenocytes from oxidative stress and serum deprivation. The scaffold of pHA-TDSC-Exos could sever as a sustained release system to treat the rat model of tendon defects. In vivo study showed that TDSC-Exos promoted early healing of injured tendons. Rats treated with TDSC-Exos had better fiber arrangement and histological scores at the injury site. Besides, the injured tendons treated with TDSC-Exos had better performance in the biomechanical testing. Therefore, the pHA-TDSC-Exos scaffold proved to facilitate tendon repair in the rat model. miR-144-3p was enriched in TDSC-Exos and promoted tenocyte proliferation and migration via targeting AT-rich interactive domain 1A (ARID1A).
TDSC-Exos enhanced tenon repair through miR-144-3p-regulated tenocyte proliferation and migration. These results suggest that TDSC-Exos can serve as a promising strategy to treat tendon injuries.
Context. The determination of the spatial geometry of the Universe plays an important role in modern cosmology. Any deviation from the cosmic curvature Ω K = 0 would have a profound impact on the ...primordial inflation paradigm and fundamental physics. Aims. In this paper, we carry out a systematic study of the prospect of measuring the cosmic curvature with the inspiral signal of supermassive black hole binaries (SMBHBs) that could be detected with TianQin. Methods. The study is based on a method that is independent of cosmological models. It extended the application of gravitational wave (GW) standard sirens in cosmology. By comparing the distances from future simulated GW events and simulated H ( z ) data, we evaluated whether TianQin produced robust constraints on the cosmic curvature parameter Ω k . More specifically, we considered three-year to ten-year observations of supermassive black hole binaries with total masses ranging from 10 3 M ⊙ to 10 7 M ⊙ . Results. Our results show that in the future, with the synergy of ten-year high-quality observations, we can tightly constrain the curvature parameter at the level of 1 σ Ω k = −0.002 ± 0.061. Moreover, our findings indicate that the total mass of SMBHB does influence the estimation of cosmic curvature, as implied by the analysis performed on different subsamples of gravitational wave data. Conclusions. Therefore, TianQin is expected to provide a more powerful and competitive probe of the spatial geometry of the Universe, compared to future spaced-based detectors such as DECIGO.
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