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Dislocations in the ZnMgO pleated nanosheets were observed from high-resolution transmission electron microscopy (TEM). The Burgers vector was identified as [formula] from the Fourier filtered TEM images. Raman spectra revealed that there were microstructure defects in the ZnMgO nanosheets with the increasing Mg content. The incorporation of the Mg impurities in the ZnMgO nanosheets may promote the congregation of oxygen vacancies and thus facilitate the generation of dislocations. The oxygen deficiency as well as surface dislocations played an important role in determining the optical properties of ZnMgO pleated nanosheets. [ABSTRACT FROM AUTHOR]

Objective: To summarize and analyze the clinical characteristics of patients diagnosed with hepatic portal venous gas (HPVG)., Methods: This was a single center retrospective observational study. All of the patients were diagnosed with HPVG. The patients were admitted to Peking University Third Hospital from January 2017 to January 2021. Demographic characteristics, clinical manifestations, laboratory tests, abdominal imaging, treatment of the primary disease, and clinical outcomes of the patients were collected via electronic medical records. The study was approved by institutional review board and the information of all the patients was kept de-identified., Results: A total of seven cases were included in the study. The median age of the patients was 67 (63, 81) years. Six of the patients were male. The seven patients all presented with sudden onset of severe abdominal pain, which was the most common symptom. Six patients developed septic shock after admission. The signs of HPVG were detected by CT scans in all the patients, showing gas embolization. It might also be found as unique "aquarium sign" in abdominal ultrosonography. Four cases were caused by intestinal lesions, including acute volvulus, intestinal obstruction, and rectal abscess. Two were caused by ischemic bowel disease and the other one was caused by severe acute pancreatitis. The gas accumulation could disappear after effective anti-shock therapy and surgery (Cases 1, 2, and 6). Two patients had good postoperative outcomes, and one patient was discharged after non-surgical treatment. However, the prognosis was poor in the patients with intestinal ischemia necrosis accompanied by shock and multiple organ dysfunction (Cases 3, 4, 5, and 7 all died)., Conclusion: The HPVG patients generally have acute abdominal pain and show up at Emergency Department. The prognosis depends on the potential cause of HPVG. The mechanism and clinical management for the appearance of gas in the portal vein is not well understood. Patients complicated with shock, ascites, and peritonitis may have intestinal necrosis, which indicates surgical intervention and higher mortality. CT is the preferred diagnostic method in standard clinical practice. Physicians need to have a comprehensive understanding of the proactive diagnostic strategy, and active treatment for the primary disease.

Objective: To explore a modified CT scoring system, its feasibility for disease severity evaluation and its predictive value in coronavirus disease 2019 (COVID-19) patients. Methods: This study was a multi-center retrospective cohort study. Patients confirmed with COVID-19 were recruited in three medical centers located in Beijing, Wuhan and Nanchang from January 27, 2020 to March 8, 2020. Demographics, clinical data, and CT images were collected. CT were analyzed by two emergency physicians of more than ten years' work experience independently through a modified scoring system. Final score was determined by average score from the two reviewers if consensus was not reached. The lung was divided into 6 zones (upper, middle, and lower on both sides) by the level of trachea carina and the level of lower pulmonary veins. The target lesion types included ground-glass opacity (GGO), consolidation, overall lung involvement, and crazy-paving pattern. Bronchiectasis, cavity, pleural effusion, etc., were not included in CT reading and analysis because of low incidence. The reviewers evaluated the extent of the targeted patterns (GGO, consolidation) and overall affected lung parenchyma for each zone, using Likert scale, ranging from 0-4 (0=absent; 1=1%-25%; 2=26%-50%; 3=51%-75%; 4=76%-100%). Thus, GGO score, consolidation score, and overall lung involvement score were sum of 6 zones ranging from 0-24. For crazy-paving pattern, it was only coded as absent or present (0 or 1) for each zone and therefore ranging from 0-6. Results: A total of 197 patients from 3 medical centers and 522 CT scans entered final analysis. The median age of the patients was 64 years, and 54.8% were male. There were 76(38.8%) patients had hypertension and 30(15.3%) patients had diabetes mellitus. There were 75 of the patients classified as moderate cases, as well as 95 severe cases and 27 critical cases. As initial symptom, dry cough occurred in 170 patients, 134 patients had fever, and 125 patients had dyspnea. Reparatory rate, oxygen saturation, lymphocyte count and CURB 65 score on admission day varied among patients with different disease severity scale. There were 50 of the patients suffered from deterioration during hospital stay. The median time consumed for each CT by clinicians was 86.5 seconds. Cronbach's alpha for GGO, consolidation, crazy-paving pattern, and overall lung involvement between two clinicians were 0.809, 0.712, 0.678, and 0.906, respectively, showing good or excellent inter-rater correlation. There were 193 (98.0%) patients had GGO, 147 (74.6%) had consolidation, and 126(64.0%) had crazy-paving pattern throughout clinical course. Bilateral lung involvement was observed in 183(92.9%) patients. Median time of interval for CT scan in our study was 7 days so that the whole clinical course was divided into stages by week for further analysis. From the second week on, the CT scores of various types of lesions in severe or critically patients were higher than those of moderate cases. After the fifth week, the course of disease entered the recovery period. The CT score of the upper lung zones was lower than that of other zones in moderate and severe cases. Similar distribution was not observed in critical patients. For moderate cases, the ground glass opacity score at the second week had predictive value for the escalation of the severity classification during hospitalization. The area under the receiver operating characteristic curve was 0.849, the best cut-off value was 5 points, with sensitivity of 84.2% and specificity of 75.0%. Conclusions: It is feasible for clinicians to use the modified semi-quantitative CT scoring system to evaluate patients with COVID-19. Severe/critical patients had higher scores for ground glass opacity, consolidation, crazy-paving pattern, and overall lung involvement than moderate cases. The ground glass opacity score in the second week had an optimal predictive value for escalation of disease severity during hospitalization in moderate patients on admission. The frequency of CT scan should be reduced after entering the recovery stage.

Objective: To investigate the impacts of blood pressure control on coronary flow reserve (CFR) in hypertensive patients., Methods: A total of 236 patients without significant coronary stenosis (defined as <50% luminal narrowing which was confirmed by coronary angiography or coronary artery CT scan) between January 2011 to July 2015 were retrospectively enrolled in this study. CFR was measured in the left anterior descending coronary artery (LAD) during adenosine triphosphate-induced hyperemia by transthoracic Doppler echocardiography. Patients were divided into hypertension group (n=173) and non-hypertension group (n=63). The hypertension patients were further divided into ideally controlled (n=31, defined as SBP <120 mmHg (1 mmHg=0.133 kPa) and DBP <80 mmHg), controlled (n=82, defined as SBP 120 to 139 mmHg and DBP <90 mmHg) and uncontrolled groups (n=60, defined as SBP≥140 mmHg and/or diastolic DBP≥90 mmHg) based on their blood pressure after systematic antihypertensive therapy and CFR values were compared among the 4 groups. Multivariate regression analyses were performed to identify the independent determinants of CFR in patients with hypertension., Results: Compared with non-hypertension group, the CFR was significantly lower in controlled (3.27±0.71 vs. 2.87±0.56, P<0.001) and uncontrolled groups (3.27±0.71 vs. 2.61±0.71, P<0.001), but was similar in ideally controlled group (3.27±0.71 vs. 3.21±0.85, P=0.68). Furthermore, the CFR was significantly lower in uncontrolled group than that of the other two hypertension groups and was significantly lower in controlled group than that of ideally controlled group. Higher blood pressure (β=-0.17, P=0.03) and age(β=-0.02, P=0.03) were independent predictors of lower CFR in patients with hypertension., Conclusions: Higher blood pressure is an independent predictor of decreased CFR in patients with hypertension. Hypertensive patients with ideally controlled blood pressure have similar CFR level as patients without hypertension.

Therapeutic hypothermia is an important treatment for cerebral resuscitation in patients after cardiac arrest. But it is rarely used for comatose survivor post-cardiac arrest in China. The patient was the first case who was in coma post cardiac arrest caused by acute myocardial infarction and given hypothermia therapy in our hospital. After coronary reperfusion and therapeutic hypothermia, the patient's sneurologic function was recovered to normal. The paper discussed the indications, contraindications, cooling methods and complications of therapeutic hypothermia.