某市政污水处理厂的微生物气溶胶排放特征及其定量风险评价研究

市政污水处理厂作为微生物气溶胶污染物的主要排放源之一,会对污水处理厂内的工作人员产生一定的健康危害,对其健康进行定量风险评价具有重要意义。在某市政污水处理厂采用Andersen FA-1型生物粒子采样器,对厂内的金黄色葡萄球菌生物气溶胶进行采样,研究该厂微生物气溶胶的排放特征,并对厂内的行政人员和工程师的人体健康进行微生物定量风险评价(QMRA)研究。结果表明,该污水处理厂倒伞曝气池较微孔曝气池产生的金黄色葡萄球菌生物气溶胶浓度更高,均属于空气强污染等级。倒伞曝气池和微孔曝气池产生的金黄色葡萄球菌生物气溶胶的粒径分布特征差别较大,其粒径峰值分别在1.1~2.1μm与4.7~7.0μm。最后,证实了大多数工作人员的人体健康风险均明显高于EPA或WHO的相应基准值。此外,工程师的健康风险高于行政人员,且成年男性的健康风险高于成年女性。

Power Aggregation Operators and Similarity Measures Based on Improved Intuitionistic Hesitant Fuzzy Sets and their Applications to Multiple Attribute Decision Making

Intuitionistic hesitant fuzzy set(IHFS)is amixture of two separated notions called intuitionistic fuzzy set(IFS)and hesitant fuzzy set(HFS),as an important technique to cope with uncertain and awkward information in realistic decision issues.IHFS contains the grades of truth and falsity in the formof the subset of the unit interval.The notion of IHFS was defined by many scholars with different conditions,which contain several weaknesses.Here,keeping in view the problems of already defined IHFSs,we will define IHFS in another way so that it becomes compatible with other existing notions.To examine the interrelationship between any numbers of IHFSs,we combined the notions of power averaging(PA)operators and power geometric(PG)operators with IHFSs to present the idea of intuitionistic hesitant fuzzy PA(IHFPA)operators,intuitionistic hesitant fuzzy PG(IHFPG)operators,intuitionistic hesitant fuzzy power weighted average(IHFPWA)operators,intuitionistic hesitant fuzzy power ordered weighted average(IHFPOWA)operators,intuitionistic hesitant fuzzy power ordered weighted geometric(IHFPOWG)operators,intuitionistic hesitant fuzzy power hybrid average(IHFPHA)operators,intuitionistic hesitant fuzzy power hybrid geometric(IHFPHG)operators and examined as well their fundamental properties.Some special cases of the explored work are also discovered.Additionally,the similarity measures based on IHFSs are presented and their advantages are discussed along examples.Furthermore,we initiated a new approach to multiple attribute decision making(MADM)problem applying suggested operators and a mathematical model is solved to develop an approach and to establish its common sense and adequacy.Advantages,comparative analysis,and graphical representation of the presented work are elaborated to show the reliability and effectiveness of the presented works.

热处理对新型坩埚熔炼的TiNi合金性能的影响

将自制的25kg级BaZrO3坩埚用于Ti-55.8%Ni合金(质量分数)的真空感应熔炼,并将合金铸锭经锻造、轧制、拉拔等工序制成φ1.0mm的TiNi合金丝材,取样经不同的制度热处理后,分析了TiNi合金丝材的拉伸性能、低周弯曲疲劳性能以及拉伸、疲劳断口形貌。结果表明:丝材经700℃保温1h水淬处理后,延伸率可达23%,韧窝尺寸变小、数量增多,且微孔数量大幅减少。此外,丝材经500℃或550℃保温20min水淬处理后,疲劳寿命得到提高,最高可达3072次,疲劳断口处贝纹线排列紧密,裂纹较短且部分存在分叉现象。

Dietary isoflavones,the modulator of breast carcinogenesis:Current landscape and future perspectives

Breast cancer is a frightful disease and serious concern in women around the world causing significant health care burden in both developed and developing countries. Extensive research work has shown that breast cancer provides strong resistance to chemical agents, U V radiation,and hormonal treatments. It is generally accepted that cell genetics is not the only main reason for breast cancer and genetic risk factors, for example, mutations in RRCAI and BRCA2 genes constitute 5%-10% of all breast cancer rates. Other related factors include age, gender,race, ethnicity, weight, reproductive factors, exo-and endogenous hormonal exposures, oral contraceptives use, ultraviolet radiation, diet, and night work(circadian disruption). Many studies have revealed that dietary isoflavones regulate breast cancer occurrence, recurrence and prognosis. Dietary isoflavones have long been part of Asian population diet and there is a significant increase as compared to dietary isoflavones intake among other populations. Dietary isoflavones are natural phytoestrogens having both estrogenic and anti-estrogenic potentials on breast cancer cells in culture, animal models and in experimental trials. This literature survey provides a comprehensive overview on the tumor preventive and tumor promoting potentials of dietary isoflavones on breast cancer. In addition, this paper provides a literature review of dietary isoflavones and their effects on up-regulation and down-regulation of different signaling pathways, genes and proteins. Finally, future perspectives of dietary isoflavones and breast cancer researchers are also critically discussed, which will provide a deeper insight regarding the inner molecular mechanisms of action.

Evaluation of non-palpable thyroid nodules by ultra sound guided fine needle aspiration cytology

The aim of this study was to see the usefulness of fine needle aspiration by “theBethesdasystem for reporting Thyroid Cytopathology” (TBS- RTC) for non palpable thyroid nodules through ultrasound-guidance for the evaluation and treatment planning of nonpalpable thyroid lesions. This study was conducted on 200 patients with non palpable thyroid nodules which are very low lying or felt on swallowing;in Department of Pathology and Radiology since January 2011 to June 2012. The patients were scanned and USG- FNAC was performed and reporting was done by “TBSRTC”. Of the 200 specimens 17 samples were nondiagnostic or unsatisfactory (Class I), 145 samples were benign (Class II), 20 samples were showing Atypical of Undetermined Significance (AUS) or Follicular Lesion of Undetermined Significance (FLUS);(Class III), 6 were showing follicular neoplasm or suspicious for a follicular neoplasm (Class IV), 7 samples were suspicious for malignancy (Class V) and 5 samples were positive for malignancy (Class VI). On comparison of ultrasound guided FNAC with histopathology the sensitivity for correct diagnosis was 93%, specificity was 86%, positive predictive value was 37%, negative predictive value was 99% and accuracy was 86%. USG-FNAC is a useful modality for the evaluation and treatment planning of nonpalpable thyroid lesions smaller than5 mmin the maximum diameter. TBSRTC is the best method of reporting but class III and IV are the main pitfall of this system for reporting Thyroid Cytopathology and show high sensitivity, specificity and accuracy.

Diagnostic accuracy of color Doppler in diagnosis of Hepatocellular carcinoma taking histopathology as gold standard

Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world and the third most common cause of cancer mortality. Despite the high numbers of patients diagnosed worldwide, HCC continues to pose challenging clinical problems. Good-quality ultra sound with careful evaluation of the entire liver can be a screening examination for HCC in patients at risk. The aim of the study was to determine the diagnostic accuracy of the Doppler sonography for differentiation of hepatocellular carcinoma (HCC) from other focal liver lesions by taking histopathology as a gold standard. It was a cross-sectional survey, conducted in the Department of Diagnostic Radiology, King Edward Medical University/Mayo Hospital, Lahore in one year from 13-12-2010 to 12-12-2011. A total of 70 patients were included in this study with focal lesions on ultrasound are included while pregnant patients are excluded. After evaluating by Doppler sonography and doing core biopsy, the patients were sent to the Department of Pathology, Mayo Hospital for histopathological examination. Histopathology was assessed for confirmation of positive and negative cases. Mean age of the patients was 60.9 ± 4.7 years. Out of 70 patients, 47 patients (67.1%) were male while remaining 23 patients (32.9%) were female. On Doppler sonography 37 cases were positive for hepatocellular carcinoma and 33 cases were negative while 36 cases were positive and 34 negative on histopathology. On Doppler sonography, sensitivity (94.4%), specificity (91.1%), diagnostic accuracy (92.8%), positive predictive value (91.8%) and negative predictive value was 93.9%. We concluded that Doppler sonography is a useful method for differen- tiation of Hepatocellular carcinoma from other focal liver lesions, detection and characterization of hepatocellular carcinoma.

利用BaZrO_3坩埚制备钛镍形状记忆合金组织及性能的研究（英文）

TiNi形状记忆合金由于其优良的合金性能,而成为商业化应用最为广泛的形状记忆合金。利用25 kg级自制BaZrO_3坩埚制备了49.3Ti-Ni (at%)合金,并将铸态合金加工成为直径为1 mm的丝材。利用XRD、氮氧化物分析仪等分析测试手段对合金的化学成分及物相组成进行研究分析,利用扫描电镜、光学显微镜对合金的显微组织进行观察,利用两台自制设备对合金丝材的形状记忆回复率及疲劳性能进行分析测试。实验结果表明,利用BaZrO_3坩埚对制备的钛镍合金的氧、氮含量能够分别达到560和17μg/g,杂质元素含量满足ASTM对于医用植入物以及医疗器械的标准要求;相对真空电弧熔炼,利用BaZrO_3坩埚感应熔炼制备的TiNi合金化学成分更加准确均匀;与石墨坩埚感应熔炼相比,利用BaZrO_3坩埚制备的TiNi合金丝材表现出更为优良的形状记忆回复率和抗疲劳性能,其形状记忆回复率在550℃保温20 min淬火后,变形量为2%时能够达到98.62%,其疲劳性能在500℃保温20 min淬火后能够达到3072次。

Polarization-selective nanogold absorber by twisted stacking

Metamaterial absorbers show great promise for applications in optical manipulation,photodetection,solar energy harvesting,and photocatalysis.In this work,we present a twisted stacked metamaterial design that serves as a plasmonic perfect absorber with polarization selectivity.Leveraging effective energy localization,the metamaterial realizes a near-unity absorbance of up to 99.6%for right circularly polarized incidence and 97.2%for left circularly polarized incidence.At a longer wavelength in the visible range,the chiral metamaterial becomes more sensitive to the polarization state of the incident wave,retaining an ultrahigh absorption of light(~94%)for only a given polarization state,that is,light in this polarization state is effectively shielded.A giant circular dichroism signal of up to 7°can be simultaneously observed.Electromagnetic field and charge distribution simulations further reveal that the ultrahigh performance of the design is attributed to the interplay between cavity coupling,magnetic resonances,and plasmonic coupling.Besides switchable and tunable chirality,the plasmonic metamaterial presents a nearperfect absorption band with tunable operational wavelengths.We envision that the high-performance chiral gold metamaterial proposed here can serve as a good candidate for light trapping,chirality sensing,polarized light detection,and polarizationenhanced photocatalysis.

Deterministic epidemic models overestimate the basic reproduction number of observed outbreaks

The basic reproduction number,R_(0),is a well-known quantifier of epidemic spread.However,a class of existing methods for estimating R_(0)from incidence data early in the epidemic can lead to an over-estimation of this quantity.In particular,when fitting deterministic models to estimate the rate of spread,we do not account for the stochastic nature of epidemics and that,given the same system,some outbreaks may lead to epidemics and some may not.Typically,an observed epidemic that we wish to control is a major outbreak.This amounts to implicit selection for major outbreaks which leads to the over-estimation problem.We formally characterised the split between major and minor outbreaks by using Otsu's method which provides us with a working definition.We show that by conditioning a‘deterministic’model on major outbreaks,we can more reliably estimate the basic reproduction number from an observed epidemic trajectory.