温度测试的外推方法

在工程上 ,经常需要测量和控制温度 ,但由于不能直接安装或焊接测温传感器 ,温度测量常非易事。文中针对工程上一些温度测试的实际需要 ,对温度测试的外推方法进行了研究。基于物体的导热规律 ,阐述了该方法的原理 ,建立了相应的数学模型 ,并详细讨论了模型的求解方法。最后 ,采用模拟实验 ,通过实测值与外推计算值在变化规律、平稳段符合程度以及最大值处的重合程度等方面的比对 ,验证了外推方法的可行性与可靠性 。

High Serum Resistin Level may be an Indicator of the Severity of Coronary Disease in Acute Coronary Syndrome

Objective To investigate the correlation between serum resistin level, cardiovascular risk factors and severity of coronary disease in acute coronary syndrome （ACS）. Methods Alter evaluated by clinical history, electrocardiography, exercise tolerance tests, laboratory tests, and coronary angiography, 220 consecutive patients with suspected chest pain were divided into normal control group, stable angina pectoris （SAP） group, and ACS group, respectively. Baseline clinical characteristics, including height, weight, waist circumference, hip circumference, white blood cell count, high-sensitive C-reactive protein （hsCRP）, total cholesterol, triglyceride, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol, were compared among three groups. ELISA was used to detect serum resistin levels. Pearson＇s correlation coefficient analysis was used to assess association between resistin and other traditional cardiovascular risk factors. Multinomial logistic regression analyses were used to define the relationship between serum resistin level and SAP or ACS. Results Serum resistin level in ACS group （1.18±0.48 μg/L） was significantly higher than that in normal control and SAP groups （0.49±0.40 and 0.66±0.40 μg/L; P〈0.01）. Only in ACS group, increased serum resistin level was significantly correlated with hsCRP （r=0.262, P=0.004） and white blood cell count （r=0.347, P=0.001）. Furthermore, serum resistin levels showed a stepwise increase with the number increase of 〉 50% stenosed coronary vessels. Multinomial logistic regression test demonstrated that serum resistin was a strong risk factor for ACS （OR=29.132, 95 % CI： 10.939-77.581, P〈0.001）. Conclusion These findings suggested the potential role of resistin in atherosclerosis and especially its involvement in ACS.

Acute pancreatitis at the beginning of the 21st century: The state of the art

Acute pancreatitis is an acute inflammatory disease of the pancreas which can lead to a systemic inflammatory response syndrome with significant morbidity and mortality in 20% of patients. Gallstones and alcohol consumption are the most frequent causes of pancreatitis in adults. The treatment of mild acute pancreatitis is conservative and supportive; however severe episodes characterized by necrosis of the pancreatic tissue may require surgical intervention. Advanced understanding of the pathology, and increased interest in assessment of disease severity are the cornerstones of future management strategies of this complex and heterogeneous disease in the 21st century.

Distribution and transformation behaviors of heavy metals during liquefaction process of sewage sludge in ethanol-water mixed solvents

Liquefaction of sewage sludge(SS)in ethanol-water cosolvents is a promising process for the preparation of bio-oil/biochar products.Effect of the combined use of ethanol and water on the distribution/transformation behaviors of heavy metals(HMs)contained in raw SS is a key issue on the safety and cleanness of above liquefaction process,which is explored in this study.The results show that pure ethanol facilitates the migration of HMs into biochar products.Pure water yields lower percentages of HMs in mobile/bioavailable speciation.Compared with sole solvent treatment,ethanol-water cosolvent causes a random/average effect on the distribution/transformation behaviors of HMs.After liquefaction of SS in pure water,the contamination degree of HMs is mitigated from high level(25.8(contamination factor))in raw SS to considerable grade(13.4)in biochar and the ecological risk is mitigated from moderate risk(164.5(risk index))to low risk(78.8).Liquefaction of SS in pure ethanol makes no difference to the pollution characteristics of HMs.The combined use of ethanol and water presents similar immobilization effects on HMs to pure water treatment.The contamination factor and risk index of HMs in biochars obtained in ethanol-water cosolvent treatment are 13.1-14.6(considerable grade)and 79.3-101.0(low risk),respectively.In order to further control the pollution of HMs,it is preferentially suggested to improve the liquefaction process of SS in ethanol-water mixed solvents by introducing conventional lignocellulosic/algal biomass,also known as co-liquefaction treatment.

Evaluation of latent links between irritable bowel syndrome and sleep quality

AIM:To examine the links between quality of sleep and the severity of intestinal symptoms in irritable bow-el syndrome(IBS).METHODS:One hundred and forty-two outpatients(110female,32 male)who met the Rome Ⅲ criteria for IBS with no psychiatric comorbidity were consecutively en-rolled in this study.Data on age,body mass index(BMI),and a set of life-habit variables were recorded,and IBS symptoms and sleep quality were evaluated using the questionnaires IBS Symptom Severity Score(IBS-SSS)and Pittsburgh Sleep Quality Index(PSQI).The associa-tion between severity of IBS and sleep disturbances was evaluated by comparing the global IBS-SSS and PSQI score(Pearson's correlation and Fisher's exact test)and then analyzing the individual items of the IBS-SSS and PSQI questionnaires by a unitary bowel-sleep model based on item response theory(IRT).RESULTS:IBS-SSS ranged from mild to severe(120-470).The global PSQI score ranged from 1 to 17(median 5),and 60 patients were found to be poor sleepers(PSQI>5).The correlation between the global IBS-SSS and PSQI score indicated a weak association(r=0.2 and 95% CI:-0.03 to 0.35,P<0.05),which becomes stronger using our unitary model.Indeed,the IBS and sleep disturbances severities,estimated as latent variables,resulted significantly high intra-subject cor-relation(posterior mean of r=0.45 and 95% CI:0.17 to 0.70,P<0.05).Moreover,the correlations between patient features(age,sex,BMI,daily coffee and alcohol intake)and IBS and sleep disturbances were also ana-lyzed through our unitary model.Age was a signif icant regressor,with patients≤50 years old showing more severe bowel disturbances(posterior mean=-0.38,P<0.05)and less severe sleep disturbances(posterior mean=0.49,P<0.05)than older patients.Higher daily coffee intake was correlated with a lower sever-ity of bowel disturbances(posterior mean=-0.31,P<0.05).Sex(female)and daily alcohol intake(modest)were correlated with less severe sleep disturbances.CONCLUSION:The unitary bowel-sleep model based on IRT revealed a strong positive correlation between the severity of IBS symptoms and sleep disturbances.

Numerical simulation of temperature distribution and heat transfer during solidification of titanium alloy ingots in vacuum arc remelting process

In order to get a better understanding of the vacuum consumable arc remelting(VAR) processes and thus to optimize them,a 3D finite element model was developed for the temperature fields and heat transfer of titanium alloy ingots during VAR process.The results show that the temperature fields obtained by the simulation are well validated through the experiment results.The temperature distribution is different during the whole VAR process and the steady-state molten pool forms at 329 s for d100 mm × 180 mm ingots.At the initial stage of remelting,the heat dissipation of crucible bottom plays an important role in the whole heat dissipation system.At the middle of remelting,the crucible wall becomes a major heat dissipation way.The effect of cooling velocity on the solidification structure of ingots was investigated based on the temperature fields and the results can well explain the macrostructure of titanium alloy ingots.

The Influence of Motivation and Depression in Second Language Learning

Depression is one of the most common illnesses affecting college students today. It is often related to low motivation. It can affect the ability to function, think, and feel. In learning process, learners are strongly affected by motivation. However, there is a group of students that is worthy of being noticed, and it seems that they have no motivation and lose interest in their study and other activities. According to a case study of Mr. WANG, the symptom of his depression was described, and the paper employing motivation theory aims at analyzing the depression severity and what causes depression, in order to uncover the students＇ inner problems and tries to find proper ways to motivate them and help them overcome the feeling of depression. Besides, the paper offers other options for solving the problem, such as speaking with a friend, partner, minister, professional counselor, or psychiatrist to canvass a different perspective

Global Convergence of a New Restarting Three Terms Conjugate Gradient Method for Non-linear Optimizations

In this note,by combining the nice numerical performance of PR and HS methods with the global convergence property of FR method,a class of new restarting three terms conjugate gradient methods is presented.Global convergence properties of the new method with two kinds of common line searches are proved.

Periodic Solutions of Lienard Equations withInfinite Delay

The problem of periodic solutions for Lienard equations with infinite delay x+(?)x+g(t,xt)=p(t)is discussed by using Mawhin's,coincidence degree theory. Some new results on the existence of periodic solutions are derived.