154 research outputs found
Water Balance Analysis of Hulun Lake, a Semi-Arid UNESCO Wetland, Using Multi-Source Data
Hulun Lake is the largest lake in northeastern China, and its basin is located in China and Mongolia. This research aims to analyze the dynamic changes in the water volume of Hulun Lake and to estimate the groundwater recharge of the lake during the past 60 years. Multi-source data were used, and water-level-data-interpolation extrapolation, water-balance equations, and other methods were applied. The proportion of the contribution of each component to the quantity of water in Hulun Lake during the last 60 years was accurately calculated. Evaporation loss was the main component in the water loss in Hulun Lake. In the last 60 years, the average annual runoff into the lake was about 1.202 billion m3, and it was the factor with the largest variation range and the leading factor affecting the changes in the quantity of water in Hulun Lake. There was groundwater recharge in Hulun Lake for a long period, and the average annual groundwater recharge was about 776 million m3 (excluding leakage). The contribution ratio of the river water, groundwater, and precipitation to the recharging of Hulun Lake was about 5:3:2. The changes in the quantity of water in Hulun Lake are affected by climate change and human activities in China and Mongolia, especially those in Mongolia
Effect of Ozone Gas Combined with Perforated Modified Atmosphere Packaging on Quality and Antioxidant Capacity of Chinese Bayberry
The aim of this study was to evaluate the combined effect of gaseous ozone (OG) and perforated modified atmosphere packaging (MAP) on the preservation of Chinese bayberry. In order to determine the optimal storage conditions, different modified atmospheres and different concentrations of OG were used separately or in combination to treat Chinese bayberry. Results showed that the optimum modified atmosphere for packaging of Chinese bayberry was 10% O2 + 10% CO2 + 80% N2, which could maintain dynamic equilibrium when a microporous film with two perforations of 100 μm in diameter per 243.39 cm2 was used, and the optimal OG concentration was 18.3 mg/m3. The single treatments with OG or perforated MAP inhibited the decay incidence and maintained high contents of total phenols, anthocyanins and flavonoids in Chinese bayberry. The combined treatment was more effective in preserving the quality of Chinese bayberry, slowing down the decline of fruit firmness, and reducing the losses of total soluble solids (TSS), titratable acid (TA) and ascorbic acid (ASA). In addition, the activities of peroxidase (POD) and superoxide dismutase (SOD) in the combined treatment group were 1.42 and 1.9 times higher than those in the untreated control, respectively, indicating reduced accumulation of H2O2 and O2-·, so that the mold free shelf life was extended up to 8 d
Risk-Cost Optimized Maintenance Strategy for Steel Bridge Subjected to Deterioration
This paper aims to develop a deteriorated bridge maintenance strategy that ensures the safe operation of steel structures and minimizes the total risk. Five common failure modes are considered for the deteriorated bridge: flexure, shear, deflection, fatigue failure for girder, and chloride attack for the concrete deck. Time-dependent and system reliability analyses are carried out to find the probability of failure under these failure modes. Risk-cost optimization is then used to determine the maintenance strategy. This method was applied to a working example. It was found that the developed maintenance strategy can predict when, where, and what to maintain for a bridge to ensure its safe and serviceable operation during its lifespan. The proposed methodology can help structural engineers and asset managers repair and maintain bridges under deterioration
Diagnostic value of serum LDH in children with refractory Mycoplasma pneumoniae pneumoniae: A systematic review and meta-analysis
BackgroundTo investigate the relationship between serum Lactate dehydrogenase (LDH) and refractory Mycoplasma pneumoniae pneumonia (RMPP) in juvenile individuals.MethodsSearch Chinese databases and English databases. The retrieval time limit is from the establishment of the database to 2022-04-27. And screening and inclusion of relevant diagnostic test literature. The QUADAS-2 method was used to evaluate the quality of the included literature. The random effects model was used to combine sensitivity, specificity, likelihood ratio, diagnostic odds ratio, summary receiver operating characteristic curve, and area under summary receiver operating characteristic curve to evaluate the prediction value of LDH for RMPP. Subgroup analyses were used to explore sources of heterogeneity.Results① A total of 29 literatures that met the criteria were included in the study, and the quality of the literature was medium and high, with a total of 702,2 patients. ② The combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the curve of the studies were: 0.75 (95% CI = 0.73–0.76), 0.73 (95% CI = 0.72–0.74), 3.61 (95% CI = 2.86–4.56), 0.30 (95% CI = 0.23–0.39), 13.04 (95% CI = 8.24–20.63), and 0.85(95% CI = 0.82–0.88). ③ The results of subgroup analysis showed that Compared with the subgroup with LDH threshold ≤400 IU/L, the AUC increased from 0.84 (95% CI = 0.80–0.87) to 0.89 (95% CI = 0.86–0.91).ConclusionsThe serum LDH has good accuracy for the diagnosis of RMPP and can serve as a diagnostic marker for RMPP
Incremental value of non-invasive myocardial work for the evaluation and prediction of coronary microvascular dysfunction in angina with no obstructive coronary artery disease
BackgroundEvidence suggests that patients suffering from angina with no obstructive coronary artery disease (ANOCA) experience coronary microvascular dysfunction (CMD). We aimed to understand the diagnosis value of noninvasive myocardial work indices (MWIs) with left ventricular pressure-strain loop (LV PSL) by echocardiography in ANOCA patients with CMD.Methods97 patients with ANOCA were recruited. All subjects underwent standard echocardiography with traditional ultrasound parameters, two-dimensional speckle-tracking echocardiography with global longitudinal strain (GLS), LV PSL with MWIs include global work index (GWI), global constructive work (GCW), global waste work (GWW) and global work efficiency (GWE). In addition, all enrolled cases underwent high-dose adenosine stress echocardiography (SE) with coronary flow velocity reserve (CFVR). CMD was defined as CFVR <2.0.ResultsOf the 97 patients with ANOCA, 52 were placed in the CMD group and 45 in the control group. GWI and GCW were decreased significantly in the CMD group compared with the control group (P < 0.001 for both). GWI and GCW were moderately correlated with CFVR (r = 0.430, P < 0.001 and r = 0.538, P < 0.001, respectively). In the multiple logistic regression analyses, GCW was identified as the only independent echocardiography parameter associated with CMD after adjusting for age and baseline APV [OR (95%CI) 1.009 (1.005–1.013); P < 0.001]. Moreover, the best predictor of CMD in patients with ANOCA using receiver operating characteristic (ROC) curve was GWI and GCW, with an area under the curve (AUC) of 0.800 and 0.832, sensitivity of 67.3% and 78.8%, specificity of 80.0% and 75.6%, respectively.ConclusionMWIs with LV PSL is a new method to detect LV systolic function noninvasively in ANOCA patients with CMD
Confucius Institute at the University of Aveiro: reviewing six years (2015-2021)
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Uber die Welch-Fraenkelschen Bazillen und ihre Verwandten im Darmkanal
Der Welch-Fraenkelsche Bazillus, der sich als ein Bodenbakterium weit im Boden verbreitet, ist obligater Anaerobier, und bekannt als Erreger des Gasoedems, welches eine chirurgisch und insbesonders kriegschirurgisch wichtige Wundinfektionskrankheit ist. Die Tatsache, dass dieses Stabchen nicht nur aus dem Boden, sondern auch aus menschlichem Darm gezuchtet wird, hat viele Autoren schon bisweilen beschaftigt. Dieser Bazillus ist Gram-positiv, gross und kraftig, abgerundet, unbeweglich und sporuliert nicht im gewohnlichen Nahrboden. Die Milch wurde sturmisch mit Gasbildung vergoren. Schon nach 20 Stunden schwamm das Kasein deutlich geschieden in truber, immer klarer werdender Molke. Die Kaseingerinnsel wurden ferner nicht wieder durch Peptonisierung gelost, noch kam es nach dem leicht sauerlich bleibenden Geruch zu Eiweissfaulniss. Die oben beschriebene Eigenschaft, die sog. Sturmische Gerinnung , ist charakteristisches Merkmal zur Diagnose-stellung des Welch-Fraenkelschen Bazillus. Der Verfasser hat aus 172 Faeces der Menschen 244 Stamme der Welch-Fraenkelschen Bazillen und 39 ahnliche Stamme, die von erstem Bazillus deutlich voneinander in Eigenstumlichkeit abweicht gezuchtet; d. h. dem Letzteren fehlt die sturmische Gerinnung. Diesen Bazillus nennt der Verfasser einen Verwandten der Welch-Fraenkelschen Bazillen , und vergleicht dieses Stabchen morphologisch und biologisch mit den Welch-Fraenkelschen Bazillen, welche er aus menschlichen Faeces und klassischem Gasoedem isoliert hat. Morphologie: Die Verwandten sind ebenso mit abgerundetem Ende 0.8-1.0μ breit, 4.0-1.0μ, nicht haufig 15μ in der Lange, zuweilen leicht gekrummt, und werden zarter als Welch-Fraenkelche Bazillen beobachtet. Sporen und Kapseln: Nicht nur in gewohnlichen Nahrboden, sondern auch in den alkalischen-, natriumphosphathaltigen Nahrsubstraten und im Hirnbrei nahm der Verfasser keine Sporen oder Kapseln wahr. Aber nur bei aus Gasoedem gezuchtetem Stamm beobachtete er beide im spezifischen antiserumhaltigen Nahrboden. Kolonientypen: Auf d
Atrial Fibrillation Follow-up Investigation to Recover Memory and Learning Trial (AFFIRMING): Rationale and Design of a Multi-center, Double-blind, Randomized Controlled Trial
Background: People with atrial fibrillation (AF) have elevated risk of developing cognitive impairment. At present, there is a dearth of randomized controlled trials investigating cognitive impairment management in patients with AF. The Atrial Fibrillation Follow-up Investigation to Recover Memory and learning (AFFIRMING) study is aimed at evaluating the potential for computerized cognitive training to improve cognitive function in patients with AF. Methods: The study is a multi-center, double-blind, randomized controlled study using a 1:1 parallel design. A total of 200 patients with AF and mild cognitive decline without dementia are planned to be recruited. The intervention group will use the adaptive training software with changes in difficulty, whereas the positive control group will use basic training software with minimal or no variation in difficulty level. At the end of 12 weeks, the participants will be unblinded, and the positive control group will stop training. The intervention group will be rerandomized 1:1 to stop training or continue training. All participants will be followed up until 24 weeks. The primary endpoint is the proportion of the improvement of the global cognitive function at week 12 compared with baseline, using the Basic Cognitive Ability Test (BCAT)
Real-time Monitoring for the Next Core-Collapse Supernova in JUNO
Core-collapse supernova (CCSN) is one of the most energetic astrophysical
events in the Universe. The early and prompt detection of neutrinos before
(pre-SN) and during the SN burst is a unique opportunity to realize the
multi-messenger observation of the CCSN events. In this work, we describe the
monitoring concept and present the sensitivity of the system to the pre-SN and
SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is
a 20 kton liquid scintillator detector under construction in South China. The
real-time monitoring system is designed with both the prompt monitors on the
electronic board and online monitors at the data acquisition stage, in order to
ensure both the alert speed and alert coverage of progenitor stars. By assuming
a false alert rate of 1 per year, this monitoring system can be sensitive to
the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos
up to about 370 (360) kpc for a progenitor mass of 30 for the case
of normal (inverted) mass ordering. The pointing ability of the CCSN is
evaluated by using the accumulated event anisotropy of the inverse beta decay
interactions from pre-SN or SN neutrinos, which, along with the early alert,
can play important roles for the followup multi-messenger observations of the
next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure
Potential of Core-Collapse Supernova Neutrino Detection at JUNO
JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve
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