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Endowing room‐temperature polymorphs with both long‐term stability and easy interconvertibility is a big challenge due to the complexity of intermolecular interactions. Herein, we present a chiral hexagonal perovskite (R‐3‐hydroxy‐1‐methylpiperidinium)[CdCl3] having two room‐temperature crystalline forms featuring obviously distinct second‐harmonic‐generation (SHG) signals with a high switching contrast of ~18 times. The two room‐temperature forms could be long‐term stable yet easily interconvertible through an irreversible thermal‐induced phase transition and a pressure‐driven backward transition, by switching hydrogen bonds via collective reorientation of ordered homochiral cations. Based on the essential role of homochiral organic cations in inducing switchable hydrogen bond linkages, this present instance provides good evidence that relatively irregular organic cations could induce more obvious inorganic chain deformations, thus endowing polymorphs with significantly different SHG signals at room temperature. [ABSTRACT FROM AUTHOR]

Objective To observe and analyze the performance of forensic science in the cases of suxa- methonium chloride poisoning, and to improve the identification of suxamethonium chloride poisoning. Methods Fifty-four cases of suxamethonium chloride poisoning were collected. The rules of determination of suxamethonium chloride poisoning were observed by the retrospective analysis of pathological and toxicological changes as well as case features. Results The pathological features of suxamethonium chloride poisoning were similar to the general changes of sudden death, which mainly included acute pulmonary congestion and edema, and partly showed myocardial disarray and fracture. Suxamethonium chloride could be detected in the heart blood of all cases and in skin tissue of part cases. Conclusion Suxa- methonium chloride poisoning has the characteristics with fast death and covert means, which are difficult to rescue and easily miss inspection. For the cases of sudden death or suspicious death, determination of suxamethonium chloride should be taken as a routine detection index to prevent missing inspection.

In this study, investigation on plant community was conducted in Heyeping subalpine meadow of Luya Mountain in Shanxi Province of China. The importance values of 36 herbaceous species, α diversity index, phylogenetic diversity index, as well as their correlations were investigated. The results showed that the species diversity of the subalpine meadow was uniformly distributed. Species richness was higher in marginal areas, indicating an 'edge effect'. The phylogenetic structure of four plots was convergent and that of 12 plots was dispersive. The phylogenetic diversity index (PD) was positively correlated with the Petrick index, Simpson index and Shannon index, while there was no significant correlation of either the net relatedness index (NRI) or the nearest taxon index (NTI) to the α diversity indices. [ABSTRACT FROM AUTHOR]

Endowing room-temperature polymorphs with both long-term stability and easy interconvertibility is a big challenge due to the complexity of intermolecular interactions. Herein, we present a chiral hexagonal perovskite (R-3-hydroxy-1-methylpiperidinium)[CdCl 3 ] having two room-temperature crystalline forms featuring obviously distinct second-harmonic-generation (SHG) signals with a high switching contrast of ~18 times. The two room-temperature forms could be long-term stable yet easily interconvertible through an irreversible thermal-induced phase transition and a pressure-driven backward transition, by switching hydrogen bonds via collective reorientation of ordered homochiral cations. Based on the essential role of homochiral organic cations in inducing switchable hydrogen bond linkages, this present instance provides good evidence that relatively irregular organic cations could induce more obvious inorganic chain deformations, thus endowing polymorphs with significantly different SHG signals at room temperature., (© 2023 Wiley-VCH GmbH.)

Aim: To ascertain the prognostic role of the T4 and N2 category in stage III pancreatic cancer according to the 8 th edition of the American Joint Committee on Cancer (AJCC) classification., Methods: Patients were collected from the Surveillance Epidemiology and End Results (SEER) database (2004-2013) and were divided into three groups: T(1-3)N2, T4N(0-1), and T4N2. Overall survival (OS) and disease-specific survival (DSS) of patients were evaluated by the Kaplan-Meier method., Results: For the first time, we found a significant difference in OS and DSS between T(1-3)N2/T4N(0-1) and T4N2 but not between T(1-3)N2 and T4N(0-1). A higher grading correlated with a worse prognosis in the T(1-3)N2 and T4N2 groups., Conclusion: Patients with stage T4N2 had a worse prognosis than those with stage T(1-3)N2/T4N(0-1) in the 8 th edition AJCC staging system for pancreatic cancer. We recommend that stage III should be subclassified into stage IIIA [T(1-3)N2/T4N(0-1)] and stage IIIB (T4N2)., Competing Interests: Conflict-of-interest statement: All authors declare no competing financial interests.

In this study, investigation on plant community was conducted in Heyeping subalpine meadow of Luya Mountain in Shanxi Province of China. The importance values of 36 herbaceous species, α diversity index, phylogenetic diversity index, as well as their correlations were investigated. The results showed that the species diversity of the subalpine meadow was uniformly distributed. Species richness was higher in marginal areas, indicating an 'edge effect'. The phylogenetic structure of four plots was convergent and that of 12 plots was dispersive. The phylogenetic diversity index (PD) was positively correlated with the Petrick index, Simpson index and Shannon index, while there was no significant correlation of either the net relatedness index (NRI) or the nearest taxon index (NTI) to the α diversity indices.

Fogs and hazes broke out many times in winter and spring of 2012-2013 in Beijing, inducing severe pollution of respirable particulate matters (PM10). As a fine particle component in PM10, PM2.5 would cause more severe air pollution if the proportion of PM2.5 to PM10 is high. Based on this, 30 monitoring stations recording the concentration of PM2.5 and PM1.0 all over Beijing were selected, and the contamination characteristics of particulate matters were analyzed, which further served to determine the characteristics of temporal and spatial pollution variations of PM2.5 and PM10. The distribution of PM2.5 and PM10 mass concentration in winter and spring in Beijing were derived by the Original Kriging interpolation method, and it was depicted from the figure that the concentration of particulate matters gradually increased from the northern mountain area to the southern part of Beijing; in the central urban area, the particulate concentration of the western region was generally higher than that of the eastern region, with certain differences between urban and rural area within some local areas. Monthly variation curve of PM2.5 and PM10 mass concentration showed single peak-valley pattern: the maximum was in January and the minimum was in April; daily variation indicated a good correlation between PM2.5 and PM10, both of which were significantly influenced by meteorological conditions; diurnal variation curve showed a double peak-valley type. Meteorological factors such as daily average temperature (degrees C), relative humidity (%), wind speed (wind scale), precipitation (mm) were chosen and their individual relationships with concentrations of PM10 and PM2.5 were investigated using Spearman rank correlation analyses. It was demonstrated that the concentrations of PM10 and PM2.5 were positively correlated with temperature and relative humidity, respectively, and strongly negatively correlated with wind speed; wind speed and relative humidity were two key factors affecting the distributions of PM2.5 and PM10 concentration.

Objective: To compare the effects of volume target pressure control ventilation (VTPC) and volume control ventilation (VCV) on respiratory mechanics in patients with respiratory failure, and to investigate the effects of ventilated parameters after salbutamol inhalation., Methods: Ten patients with mean age (68+/-5) years were intubated and mechanically ventilated for acute respiratory failure of diverse causes. After 30 minutes with VCV [tidal volume (VT) 8-10 ml/kg], measurements of respiratory mechanics were begun, and then the patients were ventilated with VTPC for 30 minutes. VCV and VTPC were repeated after salbutamol 600 microg inhalation., Results: The static compliance (Cst) was (38.4+/-2.7) ml/cm H2O (1 cm H2O=0.098 kPa) and airway resistance (Raw) was (20.1+/-2.0) cm H2O x L(-1) x s(-1) in 10 patients. With the same tidal volume, peak inspiratory pressure (PIP) and mean inspiratory flow [VT/inflation time (Tinflate)]during VTPC were lower, but peak inspiratory flow (PIF) was significantly higher than that during VCV (all P<0.05). The same plateau pressure (Pplat) was observed during VCV as during VTPC, they were (22.1+/-0.9) cm H2O vs. (23.0+/-1.2) cm H2O. After salbutamol inhalation, PIP and Raw were significantly decreased in all patients (both P<0.05), but no changes were found in Cst and Pplat. PIF and peak expiratory flow (PEF) were increased much more during two modes than before inhalation (both P<0.05), but Tinflate was decreased (P<0.05)., Conclusion: VTPC is a new mechanical ventilation mode in which closed-loop control theory is used. The airway pressure during VTPC is associated with Cst and not influenced by Raw.