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Objective To investigate the relationship between the CT parameters of degree of brain tissue displacement and intracranial pressure (ICP) in patients with closed traumatic brain injury (TBI). Methods A total of 84 patients with closed TBI were chosen from January 2018 to March 2021 in The People's Hospital of Kaizhou District. Head CT examination was performed and CT values on both sides of the midline, the ratio of CT values on both sides of the midline and the midline shift distance were measured. Pearson and partial correlation analyses were used to investigate the correlation between head CT parameters and ICP in patients with closed TBI. Receiver operating characteristic (ROC) curve was used to evaluate the predictive efficacy of CT parameters in increased ICP. Results Correlation analysis showed that the ratio of CT values on both sides of the midline (r = 0.478, P = 0.000) and midline shift distance (r = 0.378, P = 0.000) were positively correlated with ICP. ROC curve showed that the ratio of CT values on both sides of the midline, the midline shift distance and the combined index prediction of ICP were 0.79 (95%CI: 0.687-0.889, P = 0.000), 0.89 (95%CI: 0.794-0.943, P = 0.000) and 0.91 (95%CI: 0.845-0.970, P = 0.000), the sensitivity and specificity were 80.95% and 73.81%, 69.05% and 90.48%, 80.95% and 85.71%, and the prediction efficiency of the combined index was better than the ratio of CT values on both sides of the midline (t = - 2.964, P = 0.003). Conclusions The CT parameters of brain tissue displacement degree in patients with unilateral closed TBI are closely related to the ICP, and the combination of the ratio of CT values on both sides of the midline and midline shift distance can predict ICP increase more effectively.

Objective To screen the risk factors for short⁃term poor clinical prognosis in patients with low⁃grade aneurysmal subarachnoid hemorrhage (aSAH), and to construct the Nomogram model. Methods A total of 293 aSAH patients with World Federation of Neurosurgical Societies (WNFS) grade Ⅰ-Ⅱ treated by aneurysm clipping or aneurysm embolization in The People's Hospital of Kaizhou District of Chongqing from January 2016 to December 2021 were enrolled. The modified Rankin Scale (mRS) was used to evaluate the clinical prognosis at 3 months after surgery. Univariate and multivariate stepwise Logistic regression analysis was used to screen the risk factors for short⁃term poor clinical prognosis in patients with low⁃grade aSAH, and Nomogram model was constructed. The receiver operating characteristic (ROC) curve was drawn and the area under the curve (AUC) was calculated to evaluate the prediction efficiency of the model. The Bootstrap internal verification method, Hosmer⁃Lemeshow goodness of fit test and calibration curve were used to verify the model. Results Total 293 patients were divided into good prognosis group (0-2 score, n=238) and poor prognosis group (3-6 score, n=55) according to mRS score. The proportion of poor prognosis group was age ≥ 65 years old (χ2=18.516, P=0.000) and WFNS grade Ⅱ (χ2=9.491, P=0.002), the incidences of postoperative delayed cerebral ischemia (χ2=28.355, P=0.000), shunt dependent hydrocephalus (χ2=33.497, P=0.000) and intracranial hemorrhage (χ2=17.744, P=0.000) were higher than those of good prognosis group. Logistic regression analysis showed age ≥ 65 years old (OR=1.241, 95%CI: 1.021-1.772; P=0.000), postoperative delayed cerebral ischemia (OR=9.462, 95%CI: 1.302-23.823; P=0.010) and shunt dependent hydrocephalus (OR=6.092, 95%CI: 2.730-16.201; P=0.000) were the risk factors for short⁃term poor clinical prognosis in patients with low⁃grade aSAH. The Nomogram model was constructed based on the above 3 risk factors. ROC curve showed the AUC was 0.833 (95%CI: 0.772-0.897, P=0.000), when Youden index was 0.520, the corresponding sensitivity was 79.28%, specificity was 72.69%, and the cut⁃off value was 128 points. The prediction efficiency of the model was better than that of the above 3 factors alone (P=0.000, for all). Furthermore, the Bootstrap internal verification method, Hosmer⁃Lemeshow goodness of fit test and calibration curve confirmed the good discrimination (CI=0.908), stability (χ2=1.078, P=0.693) and calibration. Conclusions Age ≥ 65 years old, postoperative delayed cerebral ischemia and shunt dependent hydrocephalus are the risk factors for short⁃term poor clinical prognosis in patients with low⁃grade aSAH. The Nomogram model constructed based on these 3 factors has good predictive value for short⁃term clinical prognosis in low⁃grade aSAH.

BACKGROUND Infrared spectroscopy technology, as a green, fast, non-destructive and accurate mineral detection technology, has drawn widespread attention of geologists all over the world in recent years. In view of the high superposition of altered minerals in porphyry deposits, the inconspicuous alteration zone boundaries, many fine-grain altered minerals, and clay altered minerals, this technology has outstanding advantages in the identification of altered minerals and interpretation of exploration information. OBJECTIVES To analyze the characteristics of alteration and mineralization of the porphyry copper deposit in Pulang, Yunnan Province, and to provide the basis theory for porphyry copper deposits (especially in the Pulang deposit) exploration. METHODS The core samples in the drill ZK1801 were detected using HyLogger-3 through infrared spectroscopy technology, and the spectral data was processed and analyzed by TSG 8.0. RESULTS K-silicate alteration, epidote-chlorite alteration, chlorite-illite alteration, quartz-illite alteration and clay alteration were identified in the Pulang porphyry copper deposit. The main altered minerals included quartz, potassium feldspar, sericite, chlorite, epidote, kaolinite, smectite and illite. According to the characteristics of mineralization, it was found that copper ore bodies were widely present in the potassium silicate zone and epidote-chlorite zone. CONCLUSIONS Quartz+potash, feldspar+sericite and epdote+chlorite can be typical altered mineral assemblages for exploration of the Pulang porphyry copper deposit. The Al-OH wavelength from 2210nm to 2205nm of sericite (long-wave sericite) is closely related to mineralization, which can be used as an indicator for prospecting in the Pulang deposit.

For polymer solar cells (PSCs), the mixture of polymer donors and small-molecule acceptors (SMAs) is fine-tuned to realize a favorable kinetically trapped morphology and thus a commercially viable device efficiency. However, the thermodynamic relaxation of the mixed domains within the blend raises concerns related to the long-term operational stability of the devices, especially in the record-holding Y-series SMAs. Here, a new class of dimeric Y6-based SMAs tethered with differential flexible spacers is reported to regulate their aggregation and relaxation behavior. In their polymer blends with PM6, it is found that they favor an improved structural order relative to that of Y6 counterpart. Most importantly, the tethered SMAs show large glass transition temperatures to suppress the thermodynamic relaxation in mixed domains. For the high-performing dimeric blend, an unprecedented open circuit voltage of 0.87 V is realized with a conversion efficiency of 17.85%, while those of regular Y6-base devices only reach 0.84 V and 16.93%, respectively. Most importantly, the dimer-based device possesses substantially reduced burn-in efficiency loss, retaining more than 80% of the initial efficiency after operating at the maximum power point under continuous illumination for 700 h. The tethering approach provides a new direction to develop PSCs with high efficiency and excellent operating stability.

Abstract Background Somatosensory evoked potential (SEP) signal usually contains a set of detailed temporal components measured and identified in a time domain, giving meaningful information on physiological mechanisms of the nervous system. The purpose of this study is to measure and identify detailed time-frequency components in normal SEP using time-frequency analysis (TFA) methods and to obtain their distribution pattern in the time-frequency domain. Methods This paper proposes to apply a high-resolution time-frequency analysis algorithm, the matching pursuit (MP), to extract detailed time-frequency components of SEP signals. The MP algorithm decomposes a SEP signal into a number of elementary time-frequency components and provides a time-frequency parameter description of the components. A clustering by estimation of the probability density function in parameter space is followed to identify stable SEP time-frequency components. Results Experimental results on cortical SEP signals of 28 mature rats show that a series of stable SEP time-frequency components can be identified using the MP decomposition algorithm. Based on the statistical properties of the component parameters, an approximated distribution of these components in time-frequency domain is suggested to describe the complex SEP response. Conclusion This study shows that there is a set of stable and minute time-frequency components in SEP signals, which are revealed by the MP decomposition and clustering. These stable SEP components have specific localizations in the time-frequency domain.

Comprehensive Summary: Side‐chain engineering has emerged as a highly effective strategy for tailoring the aggregation behavior and charge transport properties of non‐fullerene small molecule acceptors (SMAs). In this study, we designed and synthesized two SMAs, namely BTPSi‐Bu and BTPSi‐Pr, respectively incorporating tributylsilyloxy and triisopropylsilyloxy groups in their outer positions. Notably, BTPSi‐Bu exhibited better planarity, crystallization, and favorable phase separation when paired with PM6 donor polymer compared to its counterpart, BTPSi‐Pr. The resulting organic solar cells, utilizing the PM6:BTPSi‐Bu blend, demonstrated a remarkable power conversion efficiency of 17.41% and a high open‐circuit voltage of 0.859 V. These findings underscore the significance of integrating trialkylsilyloxy side chains into SMAs as a rational design approach for enhancing the performance of photovoltaic systems. [ABSTRACT FROM AUTHOR]

Many organic reactions rely on CO2 sources to generate important structural units and valuable chemicals. In this study, we compared the effects of cannabidiol (CBD) and cannabidiolic acid (CBDA) on the supercritical CO2 (scCO2)-induced de/carboxylation reaction. The results showed that CBD was directly carboxylated in the ortho-position to form CBDA with up to 62% conversion. Meanwhile, CBDA decarboxylation occurred on hemp plant material via varying composition. Mechanistic studies revealed that CBD carboxylation was influenced not only by the physical properties of scCO2, but also by the vegetable matrix. [ABSTRACT FROM AUTHOR]