137 research outputs found
Operation Analysis on Refrigeration System Combined with Heat Pipe
In data center, telco equipment station and some central control rooms, there are some cases with cooling requirement all the year, their temperatures are usually controlled strictly whenever in summer or in winter. Moreover, due to clearness and safety requirement, the chiller should provide cooling water all the time even the outside environment is very cold. There had been some considerations about provide cooling capacity in cold climate with free environmental air by various heat exchangers directly. Without operating chillers, annual energy consumption on temperature control could be decreased. This paper proposed a system combined a chiller with an air-cooled heat exchanger, shown as Fig 1., there is one evaporator to provide cooled water, two condensers for the chiller and the separate type heat pipe alternatively. In warm climate, the chiller operates normally with the compressor and its condenser, the air cooling heat pipe is blocked by switching valves. In cold climate, the system is switched to the no compressor mode, the air-cooler heat exchanger could connect with the evaporator directly, the work pattern follows the separated type heat pipe, the working medium is the refrigerant still, the air cooling heat exchanger serves as the condenser of the separated type heat pipe, therefore, the evaporator is the evaporating part of the separated type heat pipe as well, the cooled water could be delivered through normal pipelines. In application of the combined refrigeration, they operation strategy for refrigeration and the heat pipe should be discussed in different climate zones. Therefore, in this paper we discussed energy consumption for cooling requirement in data center at several typical regions based on the combined cooling system. In different regions, their climates condition are different, the switching between the normal refrigeration and the heat pipe results to various annual energy consumptions
Recommended from our members
Towards universal health coverage: achievements and challenges of 10 years of healthcare reform in China.
Universal health coverage (UHC) has been identified as a priority for the global health agenda. In 2009, the Chinese government launched a new round of healthcare reform towards UHC, aiming to provide universal coverage of basic healthcare by the end of 2020. We conducted a secondary data analysis and combined it with a literature review, analysing the overview of UHC in China with regard to financial protection, coverage of health services and the reported coverage of the WHO and the World Bank UHC indicators. The results include the following: out-of-pocket expenditures as a percentage of current health expenditures in China have dropped dramatically from 60.13% in 2000 to 35.91% in 2016; the health insurance coverage of the total population jumped from 22.1% in 2003 to 95.1% in 2013; the average life expectancy increased from 72.0 to 76.4, maternal mortality dropped from 59 to 29 per 100 000 live births, the under-5 mortality rate dropped from 36.8 to 9.3 per 1000 live births, and neonatal mortality dropped from 21.4 to 4.7 per 1000 live births between 2000 and 2017; and so on. Our findings show that while China appears to be well on the path to UHC, there are identifiable gaps in service quality and a requirement for ongoing strengthening of financial protections. Some of the key challenges remain to be faced, such as the fragmented and inequitable health delivery system, and the increasing demand for high-quality and value-based service delivery. Given that China has committed to achieving UHC and 'Healthy China 2030', the evidence from this study can be suggestive of furthering on in the UHC journey and taking the policy steps necessary to secure change
Recommended from our members
Towards universal health coverage: lessons from 10 years of healthcare reform in China.
Universal health coverage (UHC) is driving the global health agenda. Many countries have embarked on national policy reforms towards this goal, including China. In 2009, the Chinese government launched a new round of healthcare reform towards UHC, aiming to provide universal coverage of basic healthcare by the end of 2020. The year of 2019 marks the 10th anniversary of China's most recent healthcare reform. Sharing China's experience is especially timely for other countries pursuing reforms to achieve UHC. This study describes the social, economic and health context in China, and then reviews the overall progress of healthcare reform (1949 to present), with a focus on the most recent (2009) round of healthcare reform. The study comprehensively analyses key reform initiatives and major achievements according to four aspects: health insurance system, drug supply and security system, medical service system and public health service system. Lessons learnt from China may have important implications for other nations, including continued political support, increased health financing and a strong primary healthcare system as basis
Mutagenetic analysis of the biosynthetic pathway of tetramate bripiodionen bearing 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione skeleton
Peer reviewe
Comparison of out-of-plane short axis with in-plane long axis for ultrasound-guided radial arterial cannulation: A systematic review with trial sequential analysis of randomised controlled trials
BackgroundIt is controversial whether the short-axis out-of-plane or long-axis in-plane approach is a better needling technique for ultrasound-guidance radial artery cannulation. We aimed to compare the efficacy and safety of the two approaches for ultrasound-guided radial artery cannulation.MethodsA systematic search of Medline, Embase, the Cochrane Library, and Web of Science for relevant articles published until 1 May 2021 was conducted. Randomised controlled trials comparing the long-axis in-plane with short-axis out-of-plane approaches were included. Review Manager software version 5.4, STATA version 14.2, and trial sequential analysis (TSA) version 0.9.5.10 Beta were used for statistical analysis. Risk of bias and methodological quality of all studies included in this review were assessed according to the Cochrane Collaboration tool for the risk of bias. Subgroup analyses and meta-regression were performed to explore sources of heterogeneity.ResultsThe rate of cannula insertion success on the first attempt was similar between the short-axis out-of-plane and long-axis in-plane approaches (RR = 1.03; 95% CI: 0.83 to 1.28; P = 0.79; I2 = 83.0%). No significant differences were observed in total time to successful cannulation between the two approaches (MD = –3.9; 95% CI:-18.30 to 10.49; P = 0.6; I2 = 97%). However, the required information size for the success rate of the first attempt and total time to successful cannulation was not reached.ConclusionIt remains inconclusive whether short-axis out-of-plane is a better choice for radial arterial cannulation than the long-axis in-plane approach. Inexperienced operators may need more attempts and longer ultrasound location time with the short-axis out-of-plane technique.Systematic review registration[https://www.crd.york.ac.uk/prospero/], identifier [CRD42021236098]
Corrigendum: Comparison of out-of-plane short axis with in-plane long axis for ultrasound-guided radial arterial cannulation: A systematic review with trial sequential analysis of randomised controlled trials
Pediatric myelin oligodendrocyte glycoprotein antibody-associated disease in southern China: analysis of 93 cases
ObjectiveTo study the clinical features of children diagnosed with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) in southern China.MethodsClinical data of children diagnosed with MOGAD from April 2014 to September 2021 were analyzed.ResultsA total of 93 children (M/F=45/48; median onset age=6.0 y) with MOGAD were involved. Seizures or limb paralysis was the most common onset or course symptom, respectively. The most common lesion locations in brain MRI, orbital MRI, and spinal cord MRI were basal ganglia and subcortical white matter, the orbital segment of the optic nerve, and the cervical segment, respectively. ADEM (58.10%) was the most common clinical phenotype. The relapse rate was 24.7%. Compared with the patients without relapse, relapsed patients had a longer interval from onset to diagnosis (median: 19 days VS 20 days) and higher MOG antibody titer at onset (median: 1:32 VS 1:100) with longer positively persistent (median: 3 months VS 24 months). All patients received IVMP plus IVIG at the acute phase, and 96.8% of patients achieved remission after one to three courses of treatment. MMF, monthly IVIG, and maintaining a low dose of oral prednisone were used alone or in combination as maintenance immunotherapy for relapsed patients and effectively reduced relapse. It transpired 41.9% of patients had neurological sequelae, with movement disorder being the most common. Compared with patients without sequelae, patients with sequelae had higher MOG antibody titer at onset (median: 1:32 VS 1:100) with longer persistence (median: 3 months VS 6 months) and higher disease relapse rate (14.8% VS 38.5%).ConclusionsResults showed the following about pediatric MOGAD in southern China: the median onset age was 6.0 years, with no obvious sex distribution difference; seizure or limb paralysis, respectively, are the most common onset or course symptom; the lesions of basal ganglia, subcortical white matter, the orbital segment of the optic nerve, and cervical segment were commonly involved in the CNS MRI; ADEM was the most common clinical phenotype; most had a good response to immunotherapy; although the relapse rate was relatively high, MMF, monthly IVIG and a low dose of oral prednisone might effectively reduce relapse; neurological sequelae were common, and possibly associated with MOG antibody status and disease relapse
Doxorubicin combined with low intensity ultrasound suppresses the growth of oral squamous cell carcinoma in culture and in xenografts
- …