Deep learning-based fully automatic screening of carotid artery plaques in computed tomography angiography: a multicenter study.

AIM: To develop and validate a deep learning (DL) algorithm for the automated detection and classification of carotid artery plaques (CAPs) on computed tomography angiography (CTA) images. MATERIALS AND METHODS: This retrospective study enrolled 400 patients (300 in the Center Ⅰ and 100 in Ⅱ). Three radiologists co-labeled CAPs, and their revised calcification status (noncalcified, mixed, and calcified) was regarded as ground truth. Center Ⅰ patients were randomly divided into training and internal validation datasets, while Center Ⅱ patients served as the external validation dataset. Carotid artery regions were segmented using a modified 3D-UNet network, followed by CAPs detection and classification using a ResUNet-based architecture in a two-step DL system. The DL model's detection and classification performance were evaluated on the validation dataset using precision-recall curve, free-response receiver operating characteristic (fROC) curve, Cohen's kappa, and ROC curve analysis. RESULTS: The DL model had achieved 83.4% sensitivity at 3.0 false positives (FPs)/CTA scan in internal validation and 78.9% in external validation. F1-scores were 0.764 and 0.769 at the optimal threshold, and area under fROC curves were 0.756 and 0.738, respectively, indicating good overall accuracy for CAP detection. The DL model also showed good performance for the ternary classification of CAPs, with Cohen's kappa achieved 0.728 and 0.703 in both validation datasets. CONCLUSION: This study demonstrated the feasibility of using a fully automated DL-based algorithm for the detection and ternary classification of CAPs, which could be helpful for the workloads of radiologists.

Identifying critical genes and pathways of doxorubicin-induced cardiomyopathy via bioinformatics analysis.

OBJECTIVE: The pathogenesis of doxorubicin (DOX) induced cardiomyopathy (DCM) is still uncertain. We aimed to identify the critical genes and pathways involved in DCM based on bioinformatics analysis. MATERIALS AND METHODS: The GSE59672 and GSE23598 mice heart tissue microarray data were obtained from Gene Expression Omnibus (GEO) database. The "limma" package of R software was used to screen the differently expressed genes (DEGs). GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) analyses were performed on DEGs by using "clusterProfiler" package in R software. The PPI (Protein - Protein Interaction) network of DEGs constructed by STRING online database and thereby the top 15 hub genes selected by cytoHubba in Cytoscape software. The hub genes interaction was performed by GeneMANIA online database. The "Corrplot" R package was employed to assess hub genes correlation. RESULTS: Finally, a total of 492 and 501 DEGs were screened in GSE59672 and GSE23598 datasets, respectively. GO analyses revealed that DEGs were mainly involved in the regulation of extracellular matrix organization, metabolic process, regulation of collagen-containing extracellular matrix. KEGG pathway analyses indicated that DEGs were mainly involved in protein digestion and absorption, ECM-receptor interaction, phagosome, and p53 signaling pathway. Finally, the 8 hub genes were identified, including Col1a1, Col3a1, Col1a2, Col6a1, Ptprc, Tyrobp, Itgb2, and Ctss. CONCLUSIONS: The present study identified a series of key genes, including Col1a1, Col3a1, Col1a2, Col6a1, Ptprc, Tyrobp, Itgb2, and Ctss. In addition, important pathways were also discovered. The results of this study may provide a novel molecular mechanism and potential therapeutic targets for DCM.

[Progress and challenge in intelligent syndromic surveillance for infectious diseases].

Intelligent syndromic surveillance is an important part of multi-point triggering and multi-channel surveillance system of intelligent early warning of infectious diseases in China, and an inevitable development process of traditional syndromic surveillance as the constant emergence of new technologies. Intelligent syndromic surveillance collects not only the medical data of patients seeking medical care in hospitals but also massive non-medical information. However, along with its rapid development, challenges in intelligent syndromic surveillance have emerged, such as information explosion, cost-effective balance, information sharing, data security and privacy. This paper summarizes the concept and development of intelligent syndromic surveillance to provide references for the method and technique development of intelligent early warning of infectious diseases and new thought for the prevention and control of infectious diseases in China and in the world.

Independent and combined associations of upper and lower limb strength with all-cause mortality in community-based older adults: findings from the Chinese Longitudinal Healthy Longevity Survey.

OBJECTIVES: Life expectancy is increasing around the world, and it has been projected that China will have the largest elderly population globally by 2033. This study aimed to examine the association of upper limb strength (ULS) and lower limb strength (LLS) with all-cause mortality based on data from the Chinese Longitudinal Healthy Longevity Survey (2012-2018). STUDY DESIGN: This is a prospective cohort study. METHODS: Participants were 2442 older adults (aged 84.98 ± 11.94 years) recruited from eight regions with a high elderly population in China. Limb muscle strength was evaluated using handgrip strength and objective physical examinations. Cox proportional hazards regression was used to analyse the association of limb muscle strength with all-cause mortality. Demographic characteristics, health status and biological markers were included as confounders. RESULTS: Over a median follow-up period of 42.2 months, 993 participants died. After adjusting for all covariates, low ULS was associated with a higher mortality risk (hazard ratio [HR] = 1.51, 95% confidence interval [CI] = 1.25-1.84), and the association of low LLS with all-cause mortality was only significant for men (HR = 1.36, 95% CI = 1.04-1.79). Participants with combined low ULS and low LLS had the highest risk of mortality compared with participants with normal limb muscle strength (HR = 2.06, 95% CI = 1.61-2.63). The combined association of ULS and LLS with mortality was robust in subgroup and sensitivity analyses. CONCLUSION: Low ULS and low LLS were independently and synergistically associated with a higher all-cause mortality risk. Considering the high prevalence of limb muscle weakness among older adults in China, especially in those aged ≥80 years, limb strength could be considered as an easy-to-perform potential mortality predictor in community health care.

Development and validation of a multiphase CT radiomics nomogram for the preoperative prediction of lymphovascular invasion in patients with gastric cancer.

AIM: To develop a nomogram to predict lymphovascular invasion (LVI) in gastric cancer by integrating multiphase computed tomography (CT) radiomics and clinical risk factors. MATERIALS AND METHODS: One hundred and seventy-two gastric cancer patients (121 training and 51 validation) with preoperative contrast-enhanced CT images and clinicopathological data were collected retrospectively. The clinical risk factors were selected by univariate and multivariate regression analysis. Radiomic features were extracted and selected from the arterial phase (AP), venous phase (VP), and delayed phase (DP) CT images of each patient. Clinical risk factors, radiomic features, and integration of both were used to develop the clinical model, radiomic models, and nomogram, respectively. RESULTS: Radiomic features from AP (n=6), VP (n=6), DP (n=7) CT images and three selected clinical risk factors were used for model development. The nomogram showed better performance than the AP, VP, DP, and clinical models in the training and validation datasets, providing areas under the curves (AUCs) of 0.890 (95% CI: 0.820-0.940) and 0.885 (95% CI:0.765-0.957), respectively. All models indicated good calibration, and decision curve analysis proved that the net benefit of the nomogram was superior to that of the clinical and radiomic models throughout the vast majority of the threshold probabilities. CONCLUSIONS: The nomogram integrating multiphase CT radiomics and clinical risk factors showed favourable performance in predicting LVI of gastric cancer, which may benefit clinical practice.

TBMaLT, a flexible toolkit for combining tight-binding and machine learning.

Tight-binding approaches, especially the Density Functional Tight-Binding (DFTB) and the extended tight-binding schemes, allow for efficient quantum mechanical simulations of large systems and long-time scales. They are derived from ab initio density functional theory using pragmatic approximations and some empirical terms, ensuring a fine balance between speed and accuracy. Their accuracy can be improved by tuning the empirical parameters using machine learning techniques, especially when information about the local environment of the atoms is incorporated. As the significant quantum mechanical contributions are still provided by the tight-binding models, and only short-ranged corrections are fitted, the learning procedure is typically shorter and more transferable as it were with predicting the quantum mechanical properties directly with machine learning without an underlying physically motivated model. As a further advantage, derived quantum mechanical quantities can be calculated based on the tight-binding model without the need for additional learning. We have developed the open-source framework-Tight-Binding Machine Learning Toolkit-which allows the easy implementation of such combined approaches. The toolkit currently contains layers for the DFTB method and an interface to the GFN1-xTB Hamiltonian, but due to its modular structure and its well-defined interfaces, additional atom-based schemes can be implemented easily. We are discussing the general structure of the framework, some essential implementation details, and several proof-of-concept applications demonstrating the perspectives of the combined methods and the functionality of the toolkit.

Experimental evaluation and structure-activity relationship analysis of bridged-ring terpenoid derivatives as novel Blattella germanica repellent.

Cockroaches are urban pests that are very difficult to control. Using repellents is a green, safe and effective strategy for their control. In order to find novel cockroach repellents, the repellent activity of 45 bridged-ring terpenoid derivatives synthesized from ß-pinene against Blattella germanica was tested. The relationship between the molecular structure of these bridged-ring terpenoid derivatives and their repellent activity against Blattella germanica was also analysed. The results show that some of the bridged-ring terpenoid derivatives exhibit good repellent activity against Blattella germanica, and six compounds (RR = 60.44-87.32%) show higher repellent activity against Blattella germanica than DEET (RR = 54.77%), making them promising for development as new cockroach repellents. Quantitative structure-activity relationship (QSAR) analysis revealed that the HOMO-1 energy, Kier and Hall index (order 2), Balaban index, and relative positive charged surface area of bridged-ring terpenoid derivatives have effects on repellent activity against Blattella germanica. The present study may provide a theoretical basis for the high-value use of ß-pinene and can be helpful to the development of novel repellents against Blattella germanica.

[The value of high-definition intelligent endoscopy combined with stroboscopy in the diagnosis and treatment of vocal cord leukoplakia].

Objective: To evaluate the clinical value of high-definition intelligent endoscopy (iSCAN) combined with stroboscopy in identifying vocal cord leukoplakia. Methods: Seventy-nine patients with vocal cord leukoplakia who underwent CO2 laser laryngeal microsurgery and diagnosed by histopathology were recruited between October 2020 to August 2021. The morphological features, microvascular morphology and mucosal waves were observed by stroboscope; SPSS 20.0 software was used for statistical analysis. Results: There were 79 patients with a total of 119 lesions (56 on left and 63 on right).Pathological examination showed that 51 sides of the vocal cords were malignant lesions (severe dysplasia, carcinoma in situ and invasive carcinoma), and 68 sides were benign lesions.Under stroboscopy, 69 sides of mucosal wave were normal or slightly decreased, and 50 sides were severely decreased or disappeared.The decrease degree of mucosal wave was positively correlated with malignant lesions (ρ=0.687, P<0.001).Under iSCAN endoscopy, there was a positive correlation between the morphological changes of microvessels at the lesion site (vertical) and the malignant lesion (ρ=0.687, P<0.001).Univariate analysis showed that lesion size, thickness, uneven color, granular elevation, peripheral erythema and asymmetry were positively correlated with malignant lesions (ρ=0.530, 0.401, 0.538, 0.315, 0.497, 0.281, P<0.05).Logistic regression analysis showed that the risk of pathological malignancy with large lesions was 5.437 times higher than those of small lesions, the vertical vascular changes under iSCAN were 8.711 times higher than that of normal vascular morphology, and the severe reduction or disappearance of mucosal waves was 9.12 times higher than that of normal or mild reduction of mucosal waves. Conclusion: ISCAN can be combined with staphyloscopy to comprehensively observe and evaluate the changes of vocal cord morphology, submucosal microvessels and mucosal wave of vocal cord in patients with vocal cord leukoplosis, thus improving the ability to distinguish benign and malignant lesions.

COVID 19 pandemic: Impact of changes experienced on social workers' professional quality of life in Singapore.

COVID-19 has impacted all spheres of life massively. Among the emerging studies on the psychosocial impact of the pandemic, few studies look specifically at how social workers are impacted. To understand this gap, this study surveyed 337 social workers. The findings showed that changes experienced in the workplace were enormous and caused secondary traumatic stress while engendering compassion satisfaction among social workers, but the presence of social support moderated to keep the secondary traumatic stress at bay. Resilience mediated association between social and workplace support and compassion fatigue. Social support seemed to have the largest effect on reducing stress through resilience. Workplace support also helped mitigate burnout. In conclusion, continued social and workplace support will be key to supporting social workers during a pandemic.

Few-cycle Yb laser source at 20 kHz using multidimensional solitary states in hollow-core fibers.

We demonstrate ultrashort pulse compression from 300 fs down to 17 fs at a repetition rate of 20 kHz and 160-µJ output pulse energy (3.2 W of average power) using multidimensional solitary states (MDSS) in a 1-meter hollow-core fiber (HCF) filled with N2O. Under static pressure, thermal limitations at this repetition rate annihilate the MDSS with suppression of spectral broadening. The results obtained in differential pressure configuration mitigate thermal effects and significantly increase the range of repetition rate over which MDSS can be used to compress sub-picosecond laser pulses.

Low-dose three-dimensional CT angiography for the evaluation of posterolateral protrusion of the vertebral artery over the posterior arch of the atlas: a quantitative anatomical comparison study of the rotational and neutral positions.

AIM: To investigate the changes in relevant anatomical parameters of posterolateral protrusion of the vertebral artery (VA) between head-neck rotational and neutral positions using low-dose three-dimensional computed tomography angiography (3D-CTA). MATERIALS AND METHODS: Low-dose 3D-CTA images obtained for various craniocervical diseases in 36 non-dominant VA side patients with neutral, left and right head-neck rotational positions were evaluated. The relevant parameters from superior and inferior views, including external diameter (ED), internal diameter (ID), transverse diameter (TD), heights and diameters of posterolateral protrusion of the VA over the posterior arch of the atlas in the neutral and rotational positions, were recorded and compared. RESULTS: There was no significant differences in the rotational angle (left/right: 31.23 ± 6.60/29.94 ± 6.09°, p>0.05). There were no significant differences in heights and diameters of bilateral VA between rotational and neutral positions (all p>0.05). The contralateral ID, ED, and TD of the rotational positions were significantly shorter than those of the neutral position (all p<0.05), while there were no significant differences in the three ipsilateral diameters (all p>0.05). CONCLUSIONS: Posterolateral protrusion of the VA is not uncommon in the population, and surgeons should be aware of its presence, especially the increased possibility of injury to the VA caused by head-neck rotation, during the operation; thus, preoperative evaluation by low-dose 3D-CTA should be considered.

[Renal insufficiency and venous thromboembolism].

Venous thromboembolism (VTE) is of high incidence and prevalence worldwide. Renal insufficiency has high disease burden with insidious development and is accompanied with disorder of coagulation system. A higher prevalence of VTE has been observed among patients with renal insufficiency whereas VTE patient with renal insufficiency had higher rates of adverse outcomes. Recent evidence indicated that renal insufficiency was an important risk factor for both short and long-term prognosis for VTE. Renal function also affects the choice of anticoagulation therapy and dosage adjustment of drugs. We conducted a comprehensive review of the pathogenesis, mechanism, prognosis and treatment strategy for VTE patients who comorbid renal insufficiency by searching the latest and most advanced national and international articles, to provide integrated information for the prevention and treatment for VTE patients.

[Preoperative plasma predictive factors of new-onset atrial fibrillation after coronary artery bypass graft surgery: A propensity score matching study].

OBJECTIVE: To study the relationship between preoperative plasma interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), homocysteine (Hcy), endothelin-1 (ET-1) levels and new-onset atrial fibrillation (AF) after coronary artery bypass grafting (CABG). METHODS: In the study, 148 patients who underwent isolated CABG in Peking University People's Hospital from January 1, 2017 to December 30, 2017 were enrolled, of whom 39 had new-onset AF. The fasting venous blood was collected within 24 hours before the surgery. The preoperative plasma IL-1, IL-6, TNF-α, Hcy, ET-1 levels were detected by enzyme-linked immunosorbent assay (ELISA). The patients were divided into AF group and non-AF group according to whether new-onset AF occurred after operation. After 1 ∶1 propensity score matching (PSM), 38 people were in each group. The paired sample t-tests were performed on the five factors' concentrations of the matched AF group and the non-AF group respectively. If the concentration values did not conform to the normal distribution, the Wilcoxon signed rank sum test was performed. Conditional Logistic regression analysis was performed on the concentrations of the five indicators to explore the correlation between preoperative plasma concentrations of IL-1, IL-6, TNF-α, Hcy, ET-1 and postoperative new-onset AF after CABG. RESULTS: After a 1 ∶1 propensity score matching, the AF group was comparable to the non-AF group. The concentrations of IL-1, IL-6, TNF-α, and Hcy in the AF group were higher than those in the non-AF group[(0.867±0.589) ng/L vs. (0.742±0.262) ng/L, 21.55 (6.50, 209.90) ng/L vs. 17.95 (3.60, 86.70) ng/L, 20.30 (5.70, 361.00) ng/L vs. 21.50 (7.50, 251.80) ng/L, (0.29±0.11) µmol/L vs. (0.27±0.09) µmol/L], but the differences were not statistically significant (P=0.165, P=0.891, P=0.817, P=0.285). After the conditional Logistic regression analysis, the above four variables were not predictors of new-onset AF after CABG. The concentrations of ET-1 in the matched AF group and non-AF group were (25.80±6.20) ng/L and (29.10±8.54) ng/L, respectively. The correlation between preoperative low plasma ET-1 concentration and the new-onset AF after CABG were statistically significant (P=0.003). After conditional Logistic regression analysis, preoperative plasma ET-1 concentration was correlated with postoperative new-onset AF after CABG (P=0.039, adjusted OR=0.637, 95%CI: 0.415-0.977). CONCLUSION: The levels of preoperative plasma IL-1, IL-6, TNF-α and Hcy in the patients with new-onset AF after CABG were higher than those in the patients without AF, but the difference was not statistically significant. Preoperative plasma low ET-1 concentration was statistically associated with new-onset AF after CABG.

[Differential diagnosis of pure ground glass nodules in lung with spectral CT imaging].

Objective: To evaluate the differential diagnostic performance of quantitative parameters derived from the spectral CT imagingin pure ground-glass nodules. Methods: A total of 44 patients with pure ground glass nodules underwent chest energy spectrum CT and with known subsequently pathological findings in the Imaging Department of the Second Affiliated Hospital of Soochow University from August 2017 to September 2019 were retrospectively analyzed. Among them, there are 18 males and 26 females, aged from 26 to 79 (51±12) years. They were divided into as the inflammatory group (n=12), pre-invasive adenocarcinoma group (n=17) and invasive adenocarcinoma group (n=15). The aforementioned three groups were further reclassified as non-invasive adenocarcinoma group (inflammatory lesion+pre-invasive lesion) and invasive adenocarcinoma group in order to evaluating the values of water concentration (WC) for the determination of adenocarcinoma infiltration status. The values of WC derived from the arterial and venous phase of the lesion, iodine concentration (IC), standardized iodine concentration (NIC) were measured respectively.The slope of the energy spectral curve (K40-70KeV) derived from the arterial and venous phase of the lesion was also calculated. One-way ANOVA analysis was performed to compare the differences of the three groups and the multiple comparison method was used for further comparing. Intraclass correlation efficient (ICC) was used to assess the consistency of the three times of measurements. The area under curve(AUC) of Receiver Operating Characteristic (ROC) was conducted to evaluate the diagnostic performance of water based values. Results: The values of WC in the arterial and venous phases were significantly different. As in the inflammatory group, the pre-invasive lesion group and the invasive adenocarcinoma group, the values of WC was (291.95±58.66) mg/cm3, (297.61±63.96) mg/cm3and (374.52±60.62) mg/cm3 of the arterial phase, and (277.07±33.78) mg/cm3, (291.74±50.49) mg/cm3 and (373.33±75.12) mg/cm3 of the venous phase, respectively(all P<0.05). Further comparison demonstrated that no significant difference was observed for the values of WC derived from the arterial phases and venous phases between the inflammatory lesion group and the pre-invasive lesion group (all P>0.05).There were an significant differences between the invasive adenocarcinoma group, the inflammatory lesion group and the pre-invasive lesion group (all P<0.05). The values of WC derived from the venous phase achieved the largest AUC (0.770) for differentiating invasive adenocarcinoma from non-invasive adenocarcinoma (inflammatory lesions+pre-invasive lesions) in the pure ground glass nodules. The sensitivity and specificity were 66.67% and 93.10%, respectively, when using 349.31 mg/cm³ as the optimal threshold. The slope of the spectral curve and iodine-related parameters (IC, NIC) derived from arterial or venous phases among the three groups were not significantly different (all P>0.05). Conclusion: The values of WC derived from the spectral CT can better distinguish inflammatory, pre-invasive lesions and invasive adenocarcinoma, which is helpful for the qualitative analysis for pure ground glass nodules.

[Establishment of a nomogram model for predicting hematoma expansion in intracerebral hemorrhage and its multidimensional evaluation].

Objective: To establish a nomogram model for hematoma expansion (HE) prediction after intracerebral hemorrhage (ICH) and evaluate its performance in a multidimensionally way. Methods: A total of 348 ICH patients who were firstly diagnosed and hospitalized in the Second Affiliated Hospital of Soochow University from January 2017 to December 2019 were collected retrospectively. There were 236 males and 112 females, and their age ranged from 18 to 94 (62.0±14.6) years. All patients were divided into HE group (n=121) or non-HE group (n=227) according to the presence or absence of HE. The clinical and imaging features were compared between the two groups. Multivariate logistic regression analysis was performed for determining the independent predicting factors for HE prediction and a Nomogram model was established by using these factors. Receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the prediction effectiveness, accuracy and clinical practicability of the model, respectively. Bootstrap method was used for internal validation. Results: There were significant differences in onset time, swirl sign, history of anticoagulants administrations, systolic blood pressure when admission, Glasgow coma scale (GCS) scores and RBC distribution width between the two groups[(1.77(1.0, 2.5) h vs 2(1, 3) h, 72 cases (59.5%) vs 94 cases (41.4%), 17 cases (14.0%) vs 15 cases (6.6%), (170.69±29.19) mmHg(1 mmHg=0.133 kPa) vs (163.84±26.07) mmHg, 11(8, 14) scores vs 14(10, 15) scores, 44.3% (41.2%, 46.8%) vs 42.4% (40.1%, 45.3%);respectively, all P<0.05]. Multivariate logistic regression analysis demonstrated that onset time (OR=0.809, 95%CI: 0.682-1.961, P=0.015), swirl sign (OR=0.562, 95%CI:0.349-0.905, P=0.018), history of anticoagulants administrations (OR=0.394, 95%CI: 0.180-1.861, P=0.020), and GCS (OR=0.881, 95%CI: 0.815-1.952, P=0.001) were the predicting factors for HE. The area under the curve (AUC) of the Nomogram model was 0.735(95%CI: 0.687-0.805), which demonstrated that the model has an ideal prediction effectiveness. The calibration curve showed that the prediction probability of HE of the model fits well with the actual probability, and with high calibration. DCA showed relatively wide range of optional threshold probability of the model (ranging from 14% to 72%), the clinical practicability of this model was high. The internal validation results showed a C-index of 0.703, indicated a good discrimination power. Conclusion: The established Nomogram model can predict the HE of ICH with good prediction effectiveness, discrimination power and with good clinical practicability, which can be capable of providing an intuitive and visual guidance tool for timely identifying ICH patients who may have HE.

A high stem to leaf ratio reduced rainfall use efficiency under altered rainfall patterns in a semi-arid grassland in northeast China.

Rainfall use efficiency (RUE) is crucial for understanding the changes in grassland productivity due to variations in future rainfall patterns. Recently, numerous studies have been conducted on the relationship between RUE and the amount of rainfall, but there has been little research on the influence of rainfall distribution and the interactive effect of rainfall amounts and distribution on RUE. Here, a simulated rainfall experiment was conducted to evaluate the impacts of rainfall amount (average rainfall amount (R0), 334 mm; decreased (R-) and increased (R+) rainfall amounts, 233 mm and 434 mm, respectively) and dry intervals (comprising 6-day, 9-day, 12-day, 15-day, 18-day and 21-day intervals between rainfall) on productivity and RUE in Leymus chinensis (Trin.) Tzvel., a dominant grass of the Eastern Eurasian Steppe. Our results showed that (1) for biomass production and RUE, moderate extension of dry intervals was conducive to enhancing total biomass production and RUE. The peak values of total biomass and RUE appeared during the 15-day interval for R-, and the 18-day interval for R0 and R+. (2) For biomass allocation, extension of dry intervals decreased the stem to leaf ratio (S/L) and the root to shoot ratio (R/S). (3) Further, the S/L ratio was significantly negatively correlated with RUE. These results suggest that variations in rainfall patterns can alter the RUE by changing the S/L ratio, and finally influence biomass production in L. chinensis. These findings have important implications for understanding and predicting the effect of future climate change on productivity in semi-arid grassland.

[Research study on nucleic acid testing of hemostatic stickers used and the surface of the recipients' hands after the inoculation of inactivated SARS-CoV-2 vaccine].

Among the staff of Beijing Chao-Yang Hospital, Capital Medical University, who received the inactivated SARS-CoV-2 vaccine on January 30 in 2021, 28 recipients were selected for this research. Samples for nucleic acid tests were collected from the surface of the recipients' both hands before and after vaccination. The hemostatic stickers used after the inoculation were also collected for nucleic acid tests. The nucleic acid tests of the samples collected from the surface of both hands of the 28 recipients before vaccination were all negative. After vaccination, the nucleic acid tests of the samples collected from the surface of both hands of recipients were positive in 3 cases, and suspicious in 8 cases, with a positive rate of 10.7%. A total of 25 hemostatic stickers used were collected, 24 of them had positive nucleic acid tests, and the rest one had suspicious nucleic acid test result, with a positive rate of 96%. The hemostatic stickers used after the inoculation have the risk of nucleic acid contamination.

70 mJ nonlinear compression and scaling route for an Yb amplifier using large-core hollow fibers.

In this Letter, we investigate the energy-scaling rules of hollow-core fiber (HCF)-based nonlinear pulse propagation and compression merged with high-energy Yb-laser technology, in a regime where the effects such as plasma disturbance, optical damages, and setup size become important limiting parameters. As a demonstration, 70 mJ 230 fs pulses from a high-energy Yb laser amplifier were compressed down to 40 mJ 25 fs by using a 2.8-m-long stretched HCF with a core diameter of 1 mm, resulting in a record peak power of 1.3 TW. This work presents a critical advance of a high-energy pulse (hundreds of mJ level) nonlinear interactions platform based on high energy sub-ps Yb technology with considerable applications, including driving intense THz, X-ray pulses, Wakefield acceleration, parametric wave mixing and ultraviolet generation, and tunable long-wavelength generation via enhanced Raman scattering.