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Background To investigate whether collateral status could modify the associations between post‐thrombectomy blood pressure (BP) measures and outcomes. Methods and Results Patients with anterior‐circulation large‐vessel‐occlusion successfully recanalized in a multicenter endovascular thrombectomy registry were enrolled. Pretreatment collateral status was graded and dichotomized (good/poor) in angiography. Maximum, minimum, and mean systolic BP (SBP) and BP variability (assessed by the SD, coefficient of variation) during the initial 24 hours after endovascular thrombectomy were obtained. The primary outcome was unfavorable 90‐day outcome (modified Rankin Scale score 3–6). Secondary outcomes included symptomatic intracranial hemorrhage and 90‐day mortality. Adjusted odds ratios (aOR) of BP parameters over the outcomes were obtained in all patients and in patients with good/poor collaterals. Among 596 patients (mean age 66 years; 59.9% males), 302 (50.7%) patients had unfavorable 90‐day outcome. In multivariable analyses, higher mean SBP (aOR, 1.59 per 10 mm Hg increment; 95% CI, 1.26–2.02; P140 mm Hg (versus ≤120 mm Hg; aOR, 4.27; 95% CI, 1.66–10.97; P=0.002), and higher SBP SD (aOR, 1.08 per 1‐SD increment; 95% CI, 1.01–1.16; P=0.02) were respectively associated with unfavorable 90‐day outcome in patients with poor collateral but not in those with good collateral. A marginal interaction between SBP coefficient of variation tertiles and collaterals on 90‐day functional outcome (P for interaction, 0.09) was observed. A significant interaction between SBP coefficient of variation tertiles and collaterals on 90‐day mortality (P for interaction, 0.03) was observed. Conclusions Higher postprocedural BP is associated with 90‐day unfavorable outcomes after successful endovascular thrombectomy in patients with poor collateral. Registration URL: https://www.chictr.org.cn; Unique identifier: ChiCTR1900022154.

Objective: We performed this study to evaluate the hemodynamic changes over time after successful endovascular recanalization in patients with symptomatic chronic intracranial artery occlusion (CIAO).Materials and Methods: We included 20 patients with symptomatic CIAO in a high-volume stroke center from June 2014 to June 2019. All subjects were evaluated with CT perfusion (CTP) studies before and after the recanalization. The relative cerebral blood flows (rCBFs) in perforating artery territory (PAT) and cortical artery territory (CAT) of occluded arteries were compared before and after the recanalization. The patients were categorized into subgroups based on the time interval from revascularization to post-procedural CTP, occlusion sites, and restenosis status. The proportion of rCBF change (rCBFc%) was compared in variable subgroups.Results: The rCBF increased significantly from 0.52 to 0.71 in PAT (P < 0.001) and from 0.59 to 0.85 in CAT (P < 0.001) after recanalization, and there were also statistical differences in variable subgroups except for those with restenosis. The median and interquartile range (IQR) of rCBFc% were 35.2 and 18.6–56.6%. For patients with short-term follow-up (55.2%), the rCBFc% was relatively higher than that in patients with mid-term (35.4%) and long-term follow-up (32.7%), although without statistical difference (P = 0.273). For patients with restenosis, the rCBFc% was significantly lower than that in patients without restenosis (18.5 vs. 37.3%, P = 0.008).Conclusions: In patients with symptomatic CIAO, the CBF may increase and be relatively stable over time after successful recanalization except for restenosis.

Objective: To explore the cerebral hemodynamic changes after revascularization in patients with hemorrhagic moyamoya disease (MMD).Materials and Methods: We retrospectively included 57 hemorrhagic MMD patients in a high-volume stroke center from January 2016 to December 2018. All subjects were evaluated with whole-brain CT perfusion (CTP) before and after surgical revascularization. Absolute and relative CTP values in the regions of cortical middle cerebral artery territory (CMT) and deep brain area (DBA) of hemorrhagic hemispheres were measured. Differences between pre- and post-operative CTP values were assessed comprehensively. The patients were categorized into subgroups based on revascularization subtypes and postoperative CTP intervals.Results: The relative cerebral blood volume (rCBV) in DBA and CMT significantly reduced in postoperative CTP (P < 0.05). The median and interquartile range of the proportion of rCBV decrease (rCBVc%) were 7.2% (2.3–13.2%). The rCBV reduction retained statistical significant in patients who received subtypes of revascularization, and in patients with variable intervals of follow-up (P < 0.05). There was no significant difference of rCBVc% between patients who received different revascularization and among patients with different postoperative CTP intervals (P > 0.05). The relative mean transit time (rMTT) and relative time to peak (rTTP) also showed downward trends, but without retainable statistical significance in stratified analysis. There was no significant change in relative cerebral blood flow (rCBF) (P > 0.05).Conclusion: In patients with hemorrhagic MMD, the CBV appeared to decrease and be relatively stable in the chronic phase after revascularization, with varying degrees of MTT and TTP shortening. However, there was no significant change in CBF.

Abstract The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (https://www.nhm.ac.uk/our-science/our-work/biodiversity/predicts.html)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

Objective: This study aimed to investigate the association between cognitive impairment and cerebral haemodynamic changes in patients with chronic vertebra-basilar (VB) stenosis.Methods: Patients with severe posterior circulation VB stenosis and infarction or a history of infarction for more than 2 weeks from January 2014 to January 2015 were enrolled (n = 96). They were divided into three groups, namely, the computed tomography perfusion (CTP) normal group, the CTP compensated group, and the CTP decompensated group. Cognitive function was assessed using a validated Chinese version of the Mini-Mental State Examination (MMSE), the Frontal Assessment Battery (FAB), and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Regression models were used to identify independent risk factors for cognitive impairment.Results: The MMSE and FAB scores of patients in the CTP decompensated group were significantly lower than those of patients in the CTP normal and CTP compensated groups (all p < 0.05). The RBANS total and its domain scores, including immediate memory, visual acuity, and delayed memory, in the CTP compensated and CTP decompensated groups were significantly lower than those in the CTP normal group (all p < 0.05). Multiple regression analyses showed that CTP compensation, CTP decompensation, severe VB tandem stenosis, and multiple infarctions were independent risk factors for cognitive impairment.Conclusions: Low perfusion caused by severe VB stenosis can lead to extensive cognitive impairments in areas such as immediate memory, visual span, and delayed memory.

Background Identification of futile recanalisation following endovascular therapy (EVT) in patients with acute ischaemic stroke is both crucial and challenging. Here, we present a novel risk stratification system based on hybrid machine learning method for predicting futile recanalisation.Methods Hybrid machine learning models were developed to address six clinical scenarios within the EVT and perioperative management workflow. These models were trained on a prospective database using hybrid feature selection technique to predict futile recanalisation following EVT. The optimal model was validated and compared with existing models and scoring systems in a multicentre prospective cohort to develop a hybrid machine learning-based risk stratification system for futile recanalisation prediction.Results Using a hybrid feature selection approach, we trained and tested multiple classifiers on two independent patient cohorts (n=1122) to develop a hybrid machine learning-based prediction model. The model demonstrated superior discriminative ability compared with other models and scoring systems (area under the curve=0.80, 95% CI 0.73 to 0.87) and was transformed into a web application (RESCUE-FR Index) that provides a risk stratification system for individual prediction (accessible online at fr-index.biomind.cn/RESCUE-FR/).Conclusions The proposed hybrid machine learning approach could be used as an individualised risk prediction model to facilitate adherence to clinical practice guidelines and shared decision-making for optimal candidate selection and prognosis assessment in patients undergoing EVT.

Abstract To address the issues of coal rib instability and high occurrence of roof falls in high extraction height fully mechanized coal mining of soft coal seams, this study comprehensively employs theoretical analysis, numerical calculations, and field industrial experiments. By analyzing the distribution characteristics of coal rib displacement and deformation instability zones under different mechanical parameters of soft coal seams, the instability mechanism of coal ribs in high extraction height mining of thick and soft coal seams is revealed, and corresponding stability control techniques for high extraction height coal ribs and supports are developed. The study shows that the stability of coal ribs in high extraction height mining fields of soft and thick coal seams decreases as the values of mechanical parameters decrease. In other words, the smaller the cohesion and deformation parameters of the coal body, the more prone the coal rib is to roof falls. By utilizing advanced deep‐hole static water infusion technology, the frequency of roof falls in extremely soft high extraction height working faces is reduced by 80%, the average depth of roof falls is decreased by 35%, and the average length of roof falls is reduced by 50%. The stability of the coal ribs is effectively improved.

Knowledge distillation is a model compression scheme commonly used to solve the problems of large scale and slow inference of BERT constant depth pre-training model.The method of ＆quot;multi-teacher distillation＆quot; can further improve the performance of the student model, while the traditional ＆quot;one-to-one＆quot; mapping method mandatory assignment strategy for the middle layer of the teacher model will lead to the abandonment of most of the middle features.The ＆quot;one-tomany＆quot; mapping method is proposed to solve the problem that the middle layer cannot be aligned during knowledge distillation, and help students master the grammar, reference and other knowledge in the middle layer of the teacher model.Experiments on several data sets in GLUE show that the student model retains 93.9% of the average inference accuracy of the teacher model, while only accounting for 41.5% of the average parameter size of the teacher model.

The vibration waves generated by pressure fluctuations can substantially impair and jeopardize the structural integrity of roadway anchorage within adjacent rock formations, thereby presenting a significant risk to the safety and operational efficiency of mining activities. In order to address this issue and elucidate the response characteristics of roadway-anchored surrounding rock subjected to P-wave and S-wave influences, this study employs a roadway that is experiencing actual impact instability within a mine situated in Xinjiang as the engineering context. The synchrosqueezing wavelet transform, enhanced by a Butterworth filter, is utilized to isolate and filter seismic wave data, thereby facilitating the extraction of time-frequency signals corresponding to both P-waves and S-waves. Subsequently, a dynamic numerical model is developed to simulate the propagation of these vibration waves. An analysis of the dynamic behavior and response characteristics of P-waves and S-waves is performed, focusing on their interaction with roadway anchoring within the surrounding rock at various stages of propagation. The results indicate that weak rock and plastic zones can absorb vibrational waves, with S-waves exhibiting a stronger absorption effect than P-waves. S-waves contribute to increased stress and displacement in the surrounding rock, leading to the accumulation of elastic energy and an expansion of the plastic zone. The rapid fluctuations in the axial force of bolts along the roadway, caused by S-waves, can result in instability within the roadway. The research findings possess considerable reference value and practical applicability for the design of anti-scour support systems in roadways.

Abstract All‐solid‐state batteries equipped with solid‐state electrolytes (SSEs) have gained significant interest due to their enhanced safety, energy density, and longevity in comparison to traditional liquid organic electrolyte‐based batteries. However, many SSEs, such as sulfides and hydrides, are highly sensitive to water, limiting their practical use. As one class of important perovskites, the Ruddlesden–Popper perovskite oxides (RPPOs), show great promise as SSEs due to their exceptional stability, particularly in terms of water resistance. In this review, the crystal structure and synthesis methods of RPPOs SSEs are first introduced in brief. Subsequently, the mechanisms of ion transportation, including oxygen anions and lithium‐ions, and the relevant strategies for enhancing their ionic conductivity are described in detail. Additionally, the progress made in developing flexible RPPOs SSEs, which are critical for flexible and wearable electronic devices, has also been summarized. Furthermore, the key challenges and prospects for exploring and developing RPPOs SSEs in all‐solid‐state batteries are suggested. This review presents in detail the synthesis methods, the ion transportation mechanism, and strategies to enhance the room temperature ionic conductivity of RPPOs SSEs, providing valuable insights on enhancing their ionic conductivity and thus for their practical application in solid‐state batteries.

Since the time of Darwin, subspecies have been recognized as an initial stage in the evolution of species. However, the impact of dispersal on subspecies richness in birds globally has received little attention, despite dispersal being a key factor in determining the rate of evolution and playing a significant role in evolutionary divergence. Therefore, it is important to conduct a comprehensive study to address this issue. In this study, we aimed to assess the association between subspecies richness (measured by the number of subspecies) and dispersal ability (measured by the hand-wing index) on a global scale, using a dataset of over 7000 bird species. Our results revealed a negative correlation between dispersal ability and the number of subspecies, without any quadratic correlation. The wing is a crucial phenotypic trait for birds, and the concept of subspecies is important in speciation theory and conservation biology. Therefore, our findings not only enhance our understanding of the association between avian morphological traits and evolutionary divergence but also have implications for the conservation of avian species diversity.

The development of cathode materials with high specific capacity is the key to obtaining high-performance lithium-ion batteries, which are crucial for the efficient utilization of clean energy and the realization of carbon neutralization goals. Li-rich Mn-based cathode materials (LRM) exhibit high specific capacity because of both cationic and anionic redox activity and are expected to be developed and applied as cathode materials for a new generation of high-energy density lithium-ion batteries. Nevertheless, the difficulty of regulating anionic redox reactions poses significant challenges to LRM, such as low initial Coulombic efficiency, poor rate capability, and fast cycling capacity and voltage decay. To address the existing challenges of LRM, this review introduces their basic physicochemical characteristics in detail, analyzes the original causes of these challenges, focuses on the recent progress of the modification strategies, and then especially discusses the development prospects of LRM from different aspects.

ObjectiveTo determine if oral gabapentin decreases the minimum alveolar concentration (MAC) of isoflurane in cats.Study designProspective, randomized, blinded, crossover, and experimental study.AnimalsA total of six healthy adult cats (three male, three female) aged 18–42 months, weighing 3.31 ± 0.26 kg.MethodsCats were randomly given oral gabapentin (100 mg cat−1) or placebo 2 h before starting MAC determination, with the crossover treatment given at least 7 days apart. Anesthesia was induced and maintained with isoflurane in oxygen. Isoflurane MAC was determined in duplicate using an iterative bracketing technique and tail clamp method. Hemodynamic and other vital variables were recorded at each stable isoflurane concentration and were compared between gabapentin and placebo treatments at lowest end-tidal isoflurane concentration when cats did not respond to tail clamping. A paired t-test was used to compare normally distributed data, and a Wilcoxon signed-rank test was applied for non-normally distributed data. Significance was set at p < 0.05. Data are mean ± standard deviation.ResultsIsoflurane MAC in the gabapentin treatment was 1.02 ± 0.11%, which was significantly lower than that in the placebo treatment (1.49 ± 0.12%; p < 0.001), decreasing by 31.58 ± 6.94%. No significant differences were found in cardiovascular and other vital variables between treatments.Conclusion and clinical relevanceOral administration of gabapentin 2 h before starting MAC determination had a significant isoflurane MAC-sparing effect in cats with no observed hemodynamic benefit.

Abstract Sociality is known to be capable of slowing individual senescence, but it is unclear whether the effect differs for reproduction versus survival in a sex‐specific manner. Here we predict that social benefits are directed toward (1) somatic maintenance in harsh environments where high survival prospects of adults over young intensify the trade‐off between current and future reproduction, and (2) females that invest more in reproduction and have a greater marginal effect if their survival is improved by reducing the cost of reproduction. These two predictions are tested with cooperatively breeding Tibetan ground tits (Pseudopodoces humilis). Across the lifetime, both mothers and fathers with helpers did not differ in brood size at fledging from their counterparts without helpers. The presence of helpers reduced survival senescence of both parents, but mothers benefited more than fathers from receiving help. Consequently, the inherent sex difference in life span and along with lifetime reproductive success, as expressed in breeders of never‐receiving help, became no longer obvious. The model of social modulation for senescence should facilitate the persistence of cooperative breeding in challenging environments.

Coal wall rib-spalling is regarded as a key technical problem influencing safe and efficient mining of fully mechanized working face with great mining height (FGH) while the coal wall stability is influenced by the strength of the coal body, of which the internal joint fissures have a crucial impact on the strength of the coal body. This research attempted to explore how the coal wall stability of FGH is influenced by the occurrence of joint fissures. This paper uses physical and numerical simulations to systematically analyze the instability characteristics and displacement law of FGH. Research results show that the form and scope of the instability of coal wall rib-spalling depend on the state of the coal seam joint fissures development area, and the development state of coal seam joint fissures is related to the combination of the coal seam joints; under the condition of hard coal, the coal wall stability is better at the inclination angle of 90°, and less stable at 45° and 135°; under the condition of medium-hard coal and joint surface inclination angle of 45° and 135°, the smaller the spacing of joint surface, the larger the area of the working face rib-spalling, and the less stable the coal wall.

Because of daily maintenance, equipment damage, gas overrun, and other force majeure factors, the continuous stopping of the working face causes the roof pressure to accumulate, which leads to causing accidents such as coal wall spalling and roof falling. To address the roof safety problem caused by continuous stoppages, the 620 working face in the Huangling mining area is taken as the research object. Through field measurement, theoretical analysis, numerical simulation, and other research methods, the influence and mechanism of stopping pressure under different rates of advance are studied. The results show that the velocity factor of roof load transfer is positively correlated with the advancing velocity of the working face; the reasonable length of the suspended roof is mainly affected by the number of caving holes and the effect of pressure relief; and comparing the two stages of advance speed of 4.8 m/d and 12.8 m/d, the periodic weighting step distance of the latter increases by 24.4% compared with the former, and the rate of increase of support load caused by stopping mining increases by 42.1% compared with the former. The roof pressure accumulation caused by stopping mining is increased. Taking appropriate measures for local forced caving of the working face can release the roof pressure and reduce the risk of local caving of the working face. The study can provide a theoretical basis for roof control of continuous stopping under similar engineering conditions.

Coal wall spalling is regarded as a key technical problem influencing safe and efficient mining of large-mining-height working faces while the distribution of abutment pressure within the limit equilibrium zone (LEZ) influences coal wall spalling within a large-mining-height working face. This research attempted to explore the distribution characteristics of abutment pressure within the LEZ in a large-mining-height working face. For this purpose, the influences of the orientation of joints on mechanical characteristics of coal with joints and on the distribution of abutment pressure within the LEZ in the large-mining-height working face were analysed by theoretical analysis and numerical simulation. Research results show that the damage variable of coal with joints first rises, then decreases, and finally increases with increasing dip angle of the joints; as the azimuth of the joints increases, the damage variable first declines, then increases; the damage variable gradually declines with increasing joint spacing; an increase in the dip angle of joints corresponds to first reduction, then growth, and a final decrease of the abutment pressure at the same position in front of the coal walls; on certain conditions, the abutment pressure at the same position within the LEZ first rises, then declines as the azimuth of joints increases; with the growth of the joint spacing, the abutment pressure at the same position within the LEZ rises. The dip angle and azimuth of joints marginally affect the abutment pressure within the LEZ.

Mutation rate is usually found to covary with many life history traits of animals such as body mass, which has been readily explained by the higher number of mutation opportunities per unit time. Although the precise reason for the pattern is not yet clear, to determine the universality of this pattern, we tested whether life history traits impact another form of genetic mutation, the motif mismatches in microsatellites. Employing published genome sequences from 65 avian species, we explored the motif mismatches patterns of microsatellites in birds on a genomic level and assessed the relationship between motif mismatches and body mass in a phylogenetic context. We found that small-bodied species have a higher average mismatches and we suggested that higher heterozygosity in imperfect microsatellites lead to the increase of motif mismatches. Our results obtained from this study imply that a negative body mass trend in mutation rate may be a general pattern of avian molecular evolution.