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Head trauma is considered as the main cause of chronic subdural hematoma (CSDH). However, many patients develop CSDH with no identified cause. Herein, we conduct a comparative study to investigate the differences in clinical characteristics and surgical outcomes of CSDH patients with and without a history of head trauma. We retrospectively reviewed CSDH patients who underwent surgical treatment in our hospital between January 2013 and December 2021. Patients were categorized into a with head trauma (WHT) group and a without head trauma (WOHT) group for comparative analysis. A total of 219 patients were included, 119 (54.3%) cases in the WHT group and 100 (45.7%) cases in the WOHT group. More cancer patients were found in the WOHT group than in the WHT group (P = 0.045). Both at discharge and 6-month follow-up, patients in the WOHT group achieved better clinical outcomes than the WHT group cases (P = 0.025 and 0.034, respectively). Furthermore, ordered multiclass logistic regression analyses indicated that a history of head trauma (odds ratio 2.151, 95% confidence interval 1.052–4.386; P = 0.036) was a risk factor significantly related to the unfavorable outcomes at 6-month follow-ups of CSDH. However, we did not find significant differences between the 2 groups in clinical manifestations, radiological characteristics, postoperative complications, mortality, and recurrence rates. CSDH patients with a history of head trauma may be more susceptible to unfavorable outcomes; thus, they should be carefully evaluated and given more attention during hospitalization and after discharge. [ABSTRACT FROM AUTHOR]

Surgical intervention for chronic subdural hematoma (CSDH) in the extremely aged population remains a difficult challenge. This study aims to investigate the clinical characteristics and surgical outcomes after twist drill craniotomy (TDC) of CSDH in super-elderly (≥80 years) patients. A retrospective analysis of super-elderly patients with CSDH who underwent TDC treatment in our hospital between January 2013 and December 2021 was performed. Their clinical characteristics and surgical outcomes were compared with those of relatively younger patients (60–79 years). Factors that may affect functional outcomes were also investigated. Fifty-nine super-elderly patients and 133 patients aged 60–79 years were included. The preoperative hematoma volume of the super-elderly patients was significantly larger than that of the 60–79 years group, whereas fewer super-elderly patients had headaches compared with the relatively younger counterparts. After surgical treatment using the TDC procedure, the incidence of complication and the hematoma recurrence rate were similar between the 2 groups. Moreover, according to the Markwalder score of the follow-up at 6 months after operation, the prognosis of the super-elderly group was not poorer than that of the patients of 60–79 years (P = 0.662). Preoperative dysfunction of coagulation (odds ratio, 28.421; 95% confidence interval, 1.185–681.677; P = 0.039) was an independent risk factor significantly related to unfavorable outcomes of super-elderly patients with CSDH. Advanced age per se does not seem to be a contraindication for the operative intervention of CSDH. Surgical treatment using the TDC procedure can still provide considerable benefits for super-elderly patients with CSDH. [ABSTRACT FROM AUTHOR]

When the high-pressure turbine guide blade works in the aero-engine, it is in the complex gas-heat environment of the combustion chamber and the turbine. The temperature distribution and strength of the blade affect the reliability and life of the aero-engine. In order to more accurately analyze the complex flow field aero-thermal parameters between the aero-engine combustion chamber and the turbine, this paper considers the influence of the non-uniform aero-thermal parameters of the combustion chamber outlet on the turbine. Taking the first-stage guide vane of an aero-engine turbine as the research object, the high and low temperature cycle thermal shock test was carried out to obtain the crack location and strength of the turbine guide vane, which provided a certain reference for improving the design of the turbine guide vane. Through the test, it is found that after 750 thermal shock cycles, fatigue cracks appear in four concentrated areas of the blade, which are distributed in the leading edge and trailing edge of the blade respectively. This shows that the temperature at the leading edge and trailing edge of the blade is higher, the heat load is higher, and the risk of damage and ablation is also the highest. Based on the experiment, the cross-component model of the combustion chamber and the blade is established. On this basis, four kinds of swirler structures at the head of the combustion chamber are designed. ANSYS FLUENT software is used to study the unsteady parameters such as the surface temperature of the guide vane under the influence of strong swirling flow. The numerical results show that when the rotation direction of the cyclone is counterclockwise, the temperature of the guide vane wall is more uniform. Compared with the clockwise rotation of the cyclone, the temperature is reduced by about 5 %, and the installation angle of the 50° cyclone blade is better than the installation angle of the 45° blade. [ABSTRACT FROM AUTHOR]

This research presents the development of innovative pyrene-based COFs aimed at enhancing photocatalytic oxidation of low-concentration nitrogen oxide. By precisely modifying the structural length and incorporating additional functional groups into pyrene-based COFs, we identified TAPPy-DMTP-COF as the most effective performer. This COF, characterized by its shortest length and the presence of -OCH 3 functional groups, demonstrated superior performance, likely due to reduced electron transfer resistance and the presence of additional oxygen active sites. Building on the potential of TAPPy-DMTP-COF, we developed a covalently linked Type-II heterostructure with g-C 3 N 4. The resulting heterostructure, 40TAPPy-DMTP-COF/g-C 3 N 4 , with a 40 % mass fraction of TAPPy-DMTP-COF, was confirmed using SEM, XRD, and other techniques. It exhibited an exceptional photocatalytic efficiency of 45.8 % and NO 3 - selectivity of 97.4 %. This remarkable performance can be attributed to improved electron communication facilitated by chemical bonding, as confirmed by XPS results. Additionally, the optimized heterostructure interface not only improved electron transfer but also inhibited the recombination of electron-hole pairs. The growth of TAPPy-DMTP-COF on the surface of g-C 3 N 4 significantly enhanced visible light absorption, as confirmed by UV–vis spectroscopy. This study not only underscores the importance of precise control over the structural features of pyrene-based COFs but also introduces a novel approach for enhancing NO oxidation. By constructing a covalently linked Type-II heterostructure, we have significantly enhanced the interface interaction within the heterostructure, leading to superior photocatalytic performance. [Display omitted] • Pyrene-based COFs were optimized based on the structural length and extra C-O-C linkage. • Covalently linked Type-II heterostructure were fabricated. • In-situ growth of TAPPy-DMTP-COF on g-C 3 N 4 accelerated the electron transfer through chemical bond. • Surface linked TAPPy-DMTP-COF significantly boosted the absorption of light and adsorption of NO and O 2. [ABSTRACT FROM AUTHOR]

Unsupervised person re-identification (Re-ID) is a challenging task due to the complexity of the camera view and the variability introduced by pedestrian pose. The irrelevant samples in sample-based contrastive learning pose a potential risk of overfitting which reduces the ability to identify similar features. Therefore, the feature representation relies on the local feature to perceive global content and overfits negative samples. This paper proposes an innovative approach: Attention-Boosted Contrastive Learning (ABC-Learning), which increases region awareness and regularizes in-memory samples. In ABC-Learning, the adjacent content aware (ACA) module is designed to enhance regional feature recognition. It enables local regions of feature maps to re-balance their output by perceiving the informative features of neighboring regions. Additionally, cluster-oriented self-attention (COS) is proposed to regularize the influence of different clusters on the contrastive learning process. The structure of COS reduces the influence of irrelevant clusters through memory data distribution. Finally, a new distance-weighted (DW) memory updating strategy is deployed to keep memory and encoder coherent. DW ensures updating consistency and knowledge transfer through relative distance detection. Our results evaluated on person Re-ID benchmarks demonstrate the promising ability of ABC-Learning to capture the regional feature information and sample weights adjustment. [ABSTRACT FROM AUTHOR]

The development of high-performance shape-stable phase change materials composites (ss-PCMCs) with enhanced thermal conductivity and high phase change enthalpy is of great importance for thermal energy storage. Herein, we report the creation of novel ss-PCMCs by incorporation of organic PCMs (1-hexadecanamine (HDA) and palmitic acid (PA)) into the biomass carbon aerogels (BCAs refer to sunflower receptacle spongy carbon aerogel (r-CA) and sunflower stem carbon aerogel (s-CA)) through a simple vacuum infusion. Due to their abundant porosity, light weight and high specific surface area, organic PCMs can be spontaneously loaded into BCAs with an ultrahigh loading rate of up to 1988 wt%. The obtained of PCM/BCAs composites show high phase change enthalpy of ranging from 207.9 kJ kg−1 to 271 kJ kg−1, in addition to their excellent thermal stability and recyclability, e.g., their phase change enthalpy nearly remains unchanged even after 50 times of melting/freezing cycles. The PCM/BCAs composites also show an enhanced thermal conductivity. Furthermore, the light-to-thermal conversion efficiency was found to be promising candidates for light-to-thermal energy storage applications on basis of their 75.6% for HDA/r-CA and 67.8% for HDA/s-CA, respectively, making them abundant resource, cost-efficiency, simple and scalable fabrication process. • HDA was first exploited as a new class of phase change material. • ss-PCMCs were fabricated by doping of PCM into biomass carbon aerogels of sunflower. • The HDA/BCAs shows high light-thermal conversion efficiency (67.8%–75.6%). • The loading rate of HDA in BCAs is up to 1988 wt % and 873%, respectively. [ABSTRACT FROM AUTHOR]

The buckling of a stiff thin film on a compliant substrate has been widely studied over the past decade due to its wide applications such as stretchable electronics, micro- and nano-metrology, and surface engineering. Instead of a single-layer compliant substrate, a bi-layer compliant substrate is usually encountered in practical applications. In this paper, the buckling of a stiff thin film on a bi-layer compliant substrate of finite thickness is studied theoretically, numerically and experimentally. The theoretical models based on the small-deformation theory and the simple finite-deformation theory accounting for the geometry change by using the energy method are both developed and presented. The good agreement among theoretical predictions, finite element analysis and experimental measurements of the buckling behavior validates the theoretical model. The influences of finite thickness of the bi-layer substrate and substrate modulus ratio on the buckling wavelength and critical buckling strain are systematically investigated. The buckling configurations at various applied strains are also measured to further validate the theoretical model. These results shed light on the influence of finite substrate thickness on buckling of the bi-layer substrate-supported thin films and are helpful to provide design guidelines in practical applications. [ABSTRACT FROM AUTHOR]

Research is restricted regarding impacts of biomass burning (BB) on fine aerosol (PM 2.5), due mainly to lack of specific BB tracers. This study aims to characterize the variability, distributions, and contributions of BB and fungal spores as sources of PM 2.5 using a multiple organic tracer approach. PM 2.5 samples were collected at four representative sites in Yangtze River Delta (YRD), China every 6 days for one year. In the laboratory, samples were analyzed for three anhydrides (levoglucosan, mannosan, and galactosan), two sugar alcohols (arabitol and mannitol), water-soluble inorganic ions, and elemental/organic carbon (EC/OC). Levoglucosan was the most abundant BB tracer (mean concentration = 81 ng/m3), and fungal spore tracers arabitol and mannitol had similar abundances (5.6 and 5.7 ng/m3, respectively). Anhydrides and sugar alcohols had high within-group correlations, indicating their respective common sources. Concentrations of tracers displayed large temporal variations but small spatial variations, suggesting strong seasonality in BB and fungal spore sources. BB sources were burning of grass, pine needles, hardwood and crop straw, which were originated from transboundary/cross-region transport and local fire spots. PCA analyses revealed that the common sources of fine aerosols in YRD were secondary inorganic aerosols, soil dust, BB and fungal spores. Image 1 • Multiple organic tracers were measured for biomass burning (BB) and fungal spores. • Tracers displayed large temporal variations but small spatial variations. • BB tracers peaked in winter, and fungal spore tracers peaked in summer. • BB types were burning of pine needles, hardwood, softwood, and crop straws. • BB accounted for 43% of total variance in PCA analysis on an annual basis. BB and fungal spore tracers exhibited strong seasonality and day-to-day variation, respectively; while their spatial variation was small, indicating larger contributions from regional sources. [ABSTRACT FROM AUTHOR]

Abstract A red emissive fluorescent probe 1,7-dimethyl-3,5-bis(4-methoxyphenyl-vinyl)-8-(10-n-butyl-10H-phenothiazine-3-yl)BODIPY 1,7-dimethyl-3,5-bis(4-methoxyphenyl-vinyl)-8-(10- n -butyl-10 H -phenothiazine-3-yl)BODIPY (avyl-BODIPY-PTZ) with a special orthogonal donor-acceptor structure was designed and synthesized for rapid, sensitive, and selective discrimination of ClO−, over other reactive oxygen species and anions. The probe displays a linear ratiometric absorption (A 578 /A 640) and fluorescence (F 599 /F 660) response toward ClO− with a fast response velocity (~10 s). The limit of detection (LOD) for ClO− was obtained as 22.6 nM from the fluorescence titration experiment. The fluorescence enhancement of the probe can be observed from the 32-fold enhancement in ratiometric value (F 599 /F 660) and the increasement of quantum yield from 0.01 at 660 nm to 0.28 at 599 nm. The oxidation of S atom in phenothiazine by ClO− to form the sulfoxide-type structure was proposed as the recognizing mechanism according to the Mass spectral analysis. The ratiometric enhancement of fluorescence was rationalized by the theoretical calculations. The orthogonal donor-acceptor structure according to optimized calculation and solvent effects of avyl-BODIPY-PTZ illustrated that the ClO− oxidation induced conversion from the nonradiative TICT process to the radiative LE process and caused the fluorescence ratiometric enhancement. The probe with low cytotoxity can successfully permeate into living cells and the cell images can be achieved in single channel. Moreover, after addition of ClO−, another bright red emission channel of the probe switched on and the probe displayed two-channel emission in living cells. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Highlights • Dural cavernous angiomas outside the middle cranial fossa could be aggressive lesions. • Dural cavernous angiomas could be multiple nodular lesions besides typical growth pattern. • A closer follow-up might be recommended for young patients with lesions adjacent to dura sinus or skull. Abstract Dural cavernous angiomas (CAs) outside the middle cranial fossa are uncommon vascular lesions that generally present with benign clinical course compared to those within the middle cranial fossa. Aggressive invasion of these lesions is less common and mainly involves the skull. Dura sinus invasion and diffused nodular growth are exceedingly rare. We presented a case of a 33-year-old male with multiple nodular CAs growing in a sheet-like pattern along the falx cerebri and convexity dura, which occluded the superior sagittal sinus, destructed calvarium and were associated with an isolated skull CA on the right forehead. Both dura sinus and convexity skull were extensively invaded by these multiple dural CAs without obvious mass effect, suggesting an aggressive infiltration pattern. Invasive dural CAs have been predominantly observed in patients <40 year-old and might be along the extra-axial vasculature. Therefore, cavernous angiomas should be considered in the diagnosis of dura-based invasive lesions and a closer follow-up might be recommended for young patients with dural CAs adjacent to dura sinus or skull. [ABSTRACT FROM AUTHOR]

Highlights • A retrospective study of 9 intracranial giant cavernous malformation patients. • The largest case series of GCM from a single neurosurgical center. • GCM is more prone to occur in children and adolescents. • Epilepsy is the most common initial presentation of GCM. • Symptomatic GCMs should be surgically treated. Abstract Intracranial giant cavernous malformations (GCMs) are rarely reported because of their extremely low incidence. Knowledge of GCM is poor. The goals of this study were to analyze the epidemiological characteristics, clinical manifestations, radiological findings, microsurgical treatment, and neurological outcomes of GCMs. From January of 2003 to December 2016, nine GCM patients who underwent neurosurgical treatment at Beijing Tiantan Hospital were chosen for analysis and their records were reviewed. We also performed an exhaustive literature search and identified all previously reported GCMs. The study population consisted of three males and six females (mean age, 25.1 years). The mean diameter of the malformations was 6.7 cm (range, 6.0–8.4 cm). The most common clinical manifestations were the symptoms caused by mass effect. Radiologically, all GCMs showed mixed T1 and T2 signals; five of them exhibited minimal enhancement after contrast administration. Gross total resection was achieved in all patients without surgical mortality. Postoperatively, three patients developed new surgical complications, including left limbs weakness and left side paralysis. The mean follow-up period after diagnosis was 69.3 months (range, 16–149 months); five patients (55.6%) had achieved full recovery and the remaining four cases (44.4%) were improved to some extent. GCM is a rare subgroup of vascular malformations; it is more prone to occur in children and adolescents. Microsurgical resection should be the treatment of choice for GCMs, and despite their giant size, excellent surgical outcomes after total removal could be achieved. [ABSTRACT FROM AUTHOR]

A novel near-infrared (NIR) fluorescent probe BODIPY-ONs for sensitive and selective detection of glutathione (GSH) was reported. The probe carried with 2,4-dinitrobenzenesulfonyl group (DNBS) as quenching group was non-fluorescent. Upon addition of glutathione, an obvious NIR fluorescence recovery centered at 656 nm was observed and the quantum yield increased to 0.48, while other thiol-lacking amino acids did not generate any change. Compared with Cys and Hcy, BODIPY-ONs showed the highest response toward GSH. The limit of detection (LOD) for GSH was calculated as 131 nM from the titration experiments. The cleavage of the suphonate induced by GSH was proposed, which was supported by Mass spectral analysis and HPLC analysis. Further theoretical calculation indicated that an intermolecular hydrogen bond assited thiolysis process was the reason that BODIPY-ONs can discriminate GSH from Cys and Hcy. Moreover, probe BODIPY-ONs could also be used for endogenous and exogenous GSH detection in living cells. [ABSTRACT FROM AUTHOR]