A Reliable Approach for Fabricating Tissue-Mimicking Phantoms with Designated Dielectric Properties from 16 MHz to 3 GHz.

Tissue-mimicking dielectric phantoms are widely used to mimic the relative permittivity and conductivity of human tissues in various medical applications. The artificial material combinations determine the characterization of dialectic phantoms. However, a method that reliably determined the composition of artificial materials with designed values of dielectric properties and frequency is still lacking. In this work, we propose a method that easily determine the compositions of phantom to mimic the human tissues from 16 MHz to 3 GHz.

Large Deflection of Foam-Filled Triangular Tubes under Transverse Loading.

In this paper, the large deflection of the foam-filled triangular tube (FFTT) is studied analytically and numerically under transverse loading. Considering the strengths of the foam and the tube, the yield criterion of FFTT is established. Based on the yield criterion, a theoretical model for the large deflection of the clamped triangular tube filled with foam under transverse loading is developed. The numerical simulations are carried out using ABAQUS/Standard software, and the analytical results are compared with the numerical ones. The effects of foam strength, thickness of the tube, and the width of the punch on the load-bearing capacity and energy absorption of the clamped FFTT loaded transversally are discussed in detail. It is demonstrated that the load-bearing ability and the energy absorption increase with increasing foam strength, tube thickness, and punch width. The closer the loading position is to the clamped end, the greater the increases in the capacity of load bearing and the energy absorption of the triangular tube filled with foam. The theoretical model can be used to foresee the large deflection of metal FFTT under transverse loading.

Sensitivity investigation of open-ended coaxial probe in skin cancer detection.

Open-ended coaxial probe method is one of the most common modalities in measuring dielectric properties (DPs) of biological tissues. Due to the significant differences between the tumors and normal tissues in DPs, the technique can be used to detect skin cancer in the early stage. Although various studies have been reported, systematic assessment is in urgent need to advance it to clinical applications, for its parameters interactions and detecting limitations remained unclear. In this study, we aim to provide a comprehensive examination of this method, including the minimum detectable tumor size by using a three-layer skin model via simulation and demonstrated that open-ended coaxial probe method can be used for detection of early-stage skin cancer. The smallest detecting size are subject to different subtypes: for BCC, inside the skin is 0.5 mm radius × 0.1 mm height; for SCC, inside the skin is 1.4 mm × 1.3 mm in radius and height; the smallest distinguishing size of BCC is 0.6 mm × 0.7 mm in radius and height; for SCC is 1.0 mm × 1.0 mm in radius and height; for MM is 0.7 mm × 0.4 mm in radius and height. The experiment results showed that sensitivity was affected by tumor dimension, probe size, skin height, and cancer subtype. The probe is more sensitive to cylinder tumor radius than height growing on the surface of the skin while the smallest size probe is the most sensitive among the working probes. We provide a detailed systematic evaluation of the parameters employed in the method for further applications.

Prevalence of Percutaneous Injuries and Associated Factors Among a Sample of Midwives in Hunan Province, China.

Background: Percutaneous injuries and blood-borne-related infections pose occupational hazards to healthcare professionals. However, the prevalence and associated factors for these hazards among midwives in Hunan Province, China are poorly documented. Methods: A cross-sectional study was conducted among a sample of 1,282 eligible midwives in the cities of Yongzhou, Chenzhou, Hengyang, and Changsha in Hunan Province, China, from January 2017 to July 2017. The association of selected independent variables with percutaneous injuries was investigated using binary logistic regression. Results: 992 participants responded (77.3%), and within the previous 12 months, 15.7% experienced percutaneous injuries. In multivariate analysis, hospital size, age, length of employment as a midwife, weekly working hours, and three aspects of Hospital Safety Climate Scale were associated with percutaneous injuries. The risk of percutaneous injuries among the midwives working in hospitals with ≤399 beds was higher than that among those working in hospitals with ≥400 beds by nearly 3 times. Furthermore, the percutaneous injury prevalence of midwives decreased as age increased. Moreover, the probability of percutaneous injuries among the midwives with weekly working hours of >40 was 4.35 times higher compared with that among midwives with weekly working hours of ≤40. Conclusion/Application to practice: The prevalence of percutaneous injuries among midwives in the study hospitals was substantial. Our results further proved that risk mitigation strategies tailored to midwives are needed to reduce this risk. These strategies include ensuring a positive organizational climate, providing highly safe devices, and reducing the workload.

Assessment of prevalence and risk factors of helicobacter pylori infection in an oilfield Community in Hebei, China.

BACKGROUND: Only a paucity of large-scale perspective and cross-sectional studies on H. pylori infection in China have been published. The purpose of this study was to investigate the prevalence and risk factors for H. pylori infection among residents of Jidong community located in Hebei Province of China. METHODS: A perspective, cross-sectional study was conducted in Jidong community. Questionnaires and 13C-urea breath test were performed, and 10-ml blood samples were obtained for laboratory tests. RESULTS: Four thousand seven hundred ninety-six subjects were enrolled in this study, and 2506 (52.25%) were H. pylori positive. There was no difference in prevalence between both sexes (P = 0.5974). Age (P = 0.004) and education level (P = 0.0128) were significantly associated with H. pylori infection, and there were statistical trends in the prevalence across five age subgroups (χ2 test for trend = 23.5; P < 0.001) and education levels (χ2 test for trend = 19.50; P < 0.001). H. pylori infection was also associated with marital status (P = 0.0243), source of drinking water (P = 0.0433), frequency of eating raw garlic (P = 0.0310), alcohol drinking (P = 0.0207), knowledge about H. pylori transmission route (P = 0.0125) and related diseases (P = 0.0257). Age, alcohol drinking and knowledge about transmission route were found to be independent predictors of H. pylori infection. CONCLUSIONS: More than half of the population was infected with H. pylori in Jidong community. The socio-demographic profiles, socio-economic factors and lifestyle are worthy taking into consideration to prevent diseases associated with H. pylori infection. Understanding the prevalence and risk patterns for H. pylori infection in China will help in prioritizing public health efforts to better manage the H. pylori infection.

Epicardial adipose tissue volume is associated with non-alcoholic fatty liver disease and cardiovascular risk factors in the general population.

BACKGROUND: Epicardial adipose tissue (EAT) is considered an important source of bioactive molecules that can influence coronary arteries directly and is related to the concurrent presence of both obstructive coronary stenosis and myocardial ischemia independently. Non-alcoholic fatty liver disease (NAFLD) has become an emergent health problem worldwide. AIM: This cross-sectional study aimed to address the relationship between the volume of EAT and NAFLD and other cardiovascular risk factors in the general population. MATERIALS AND METHODS: In this study, we selected a total of 2,238 participants aged at least 40 years from the Jidong community in Tangshan, China. The 64-slice CT was used to survey the volume of EAT and liver ultrasonography was used for the diagnosis of NAFLD. The study cohorts were compared according to EAT volume. RESULTS: Cardiovascular risk factors, such as coronary artery calcium score, carotid intima-media thickness, NAFLD, and ideal cardiovascular health metrics were also found to be related to EAT. In multivariate logistic regression analysis, NAFLD groups showed significant association with higher EAT volume, after correcting for main cardiovascular disease risk factors (OR [95% CI], 1.407 [1.117, 1.773]). CONCLUSION: Our findings in a general community population provide evidence that EAT is strongly associated with NAFLD and other cardiovascular risk factors.

Relation of serum uric acid to asymptomatic proximal extracranial artery stenosis in a middle-aged Chinese population: a community-based cross-sectional study.

OBJECTIVE: Serum uric acid (SUA) has been associated with cardiovascular diseases, including atherosclerosis and carotid artery stenosis. However, data on the relationship between SUA level and proximal extracranial artery stenosis (PEAS) are limited. Therefore, this study investigates the association between SUA levels and the risk of PEAS in asymptomatic Chinese population. SETTING: This community-based cross-sectional study was conducted in Jidong Community Hospital, Tangshan, Hebei, China between July 2013 and August 2014. PARTICIPANTS: The study examined 3325 asymptomatic participants (40-60 years) to evaluate the risk of PEAS. RESULTS: For the participants stratified into quartiles based on gender-specific SUA levels, the prevalence of PEAS increased from Q1 to Q4 from 12.3% to 29.8% in the vertebral artery (VA), and from 2.8% to 5.8% in the common carotid artery. The proportion of PEAS relative to the detected number of arterial stenosis was lower in Q1 than in Q2-Q4. The multivariable ORs and 95% CI of PEAS in the second through fourth compared with the lowest quartiles for arterial stenosis were 1.278 (0.980 to 1.665), 1.117 (0.851 to 1.468) and 1.375 (1.033 to 1.830) (ptrend=0.0399); and for VA stenosis, 1.285 (0.966 to 1.709), 1.085 (0.808 to 1.457) and 1.439 (1.061 to 1.952) (ptrend=0.0235). CONCLUSION: Elevated SUA concentration is significantly associated with PEAS in an asymptomatic middle-aged Chinese population, and vertebral arteries appeared to be the most vulnerable vessels.

Association between serum uric acid and atrial fibrillation: a cross-sectional community-based study in China.

OBJECTIVES: To investigate the effects of gender on the association of serum uric acid (SUA) levels and atrial fibrillation (AF) prevalence in a community-based Chinese population. SETTING: Data were obtained from annual Jidong Oilfield employee and family member health checkups. The Jidong community is geographically located in Tangshan City in northern China. PARTICIPANTS: A total of 9078 residents were invited to take part in the survey and provided informed consents. Individuals without data of ECG or SUA were excluded, leaving 8937 residents in our study. PRIMARY AND SECONDARY OUTCOME MEASURES: SUA was measured at baseline using the uricase-peroxidase method. Hyperuricaemia was defined as a SUA level >7.0 mg/dL in men and >5.7 mg/dL in women. AF was diagnosed based on ECG findings and/or any medical history of AF from referring physicians. The crude and independent association between SUA levels and AF prevalence was evaluated with logistic regression analysis. RESULTS: AF prevalence was 0.6% (53/8937). Participants with hyperuricaemia had a higher AF prevalence compared with those with normal SUA levels (1.1% vs 0.5%; P=0.02). Hyperuricaemia was correlated with AF after adjustment for various cardiovascular risk factors in all participants (P=0.03, OR 2.051, 95% CI 1.063 to 3.856). This correlation was particularly stronger in women compared with men (P<0.001, OR 6.366, 95% CI 2.553 to 15.871 in women and P=0.96, OR 1.025, 95% CI 0.400 to 2.626 in men). CONCLUSIONS: We demonstrated a significant association between increased SUA levels and AF prevalence in a Chinese population. Our data indicate that there is a gender-specific mechanism underlying the relationship between SUA and AF.

Nonalcoholic Fatty Liver Disease and Coronary Artery Calcification in a Northern Chinese Population: a Cross Sectional Study.

Nonalcoholic fatty liver disease (NAFLD) has become an emerging health issue with a high prevalence in general population. The cross-sectional study was performed to investigate the association between NAFLD and coronary artery calcification (CAC) in individuals from northern city of China. A total of 2345 participants aged ≥40 (1035 men and 1310 women) were selected from the Jidong community of Tangshan city. Liver ultrasonography was used to the diagnosis of NAFLD. A 64-slice CT scanner was used to determine coronary artery calcification score (CACS), with CACS > 0 defined to be the presence of CAC. The risk level of coronary heart disease (CHD) was graded by CACS according to the 4 commonly used thresholds in clinical practice (0, 10, 100, and 400 Agatston units). NAFLD was significantly associated with CAC (crude OR: 1.631, 95% CI: 1.295-2.053, adjusted OR: 1.348, 95% CI: 1.030-1.765). The association between NAFLD and increased risk level of CHD (Crude OR: 1.639 95% CI: 1.303-2.063; adjusted OR: 1.359 95% CI: 1.043-1.770) was observed. The associations between NAFLD and CAC or increased risk level of CHD were significant in female but not in male. Our finding further confirmed the association between NAFLD and CAC, especially in Asian population.

Parity and serum lipid levels: a cross-sectional study in chinese female adults.

Reproductive factors have been shown to correlate with lipid metabolism. The aim of this study was to investigate the relationship between parity and serum lipid levels in community-based Chinese female adults. A total of 4,217 female participants were enrolled. Parity was recorded according to questionnaire and serum lipid profile, including triglycerides (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C), was measured. Logistic regression models were used to analyze the association of parity to serum lipid levels, while adjusting for demographics and metabolic risk factors. Parity in this population ranged from 0 to 7. After adjusting for potential confounders, it indicated that females with more than 2 parities appeared to be less likely to suffer from abnormal serum TC level compared with nulliparae (parity = 2, odds ratio (OR) = 0.457, 95% confidence interval (CI) = 0.284-0.736; parity ≥ 3, OR = 0.363, 95% CI = 0.202-0.653). These findings suggested that parity could correlate with lipid metabolism in Chinese women. Individuals with higher parity appeared to have a lower total cholesterol in blood.

[Gender specific associations between early puberty and behavioral and emotional characteristics in children].

OBJECTIVE: To understand the gender specific association between early puberty and behavioral and emotional characteristics in children. METHODS: The questionnaire survey was conducted among the girls in grade 2-3, boys in grade 3-4 and both girls and boys in grade 7-8 selected through cluster sampling in 2 middle schools and 2 primary schools in Beijing and Shenyang respectively in November 2014. The questionnaire contents included general information, physical activity and video time, pubertal development scale (PDS) and strength and difficulties questionnaire (SDQ). Descriptive statistics were used to describe the prevalence of early puberty and the detection rate of abnormal behavioral problems. The effects of early puberty on behavioral and emotional problems were estimated with univariate and multivariate logistic regression analyses. The odds ratios and their 95% confidence intervals were calculated. RESULTS: A total of 3253 complete questionnaires were collected, the prevalence of early puberty was 15.9% (518). The detection rate (number) of abnormal emotional symptoms, conduct problems, hyperactivity/inattention, peer relationship problems, pro-social behaviors and total difficulties were 8.3% (269), 9.1% (297), 6.5% (211), 16.4% (534), 9.2% (299) and 13.8% (448) respectively. Multivariate logistic regression analysis showed that early puberty was the risk factor for conduct problems (OR=2.260, 95% CI: 1.322-3.863) and hyperactivity/inattention (OR=1.980, 95% CI: 1.111-3.527) in the girls, and early puberty was risk factor for total difficulties in boys (95%CI: 1.018-2.063). CONCLUSIONS: Early puberty might increase the risk of conduct problems and hyperactivity/inattention in girls and increase the risk of total difficulties in boys. It is important to conduct gender specific psychological intervention among adolescents for improving their physical and mental health.

Condensing biomedical journal texts through paragraph ranking.

MOTIVATION: The growing availability of full-text scientific articles raises the important issue of how to most efficiently digest full-text content. Although article titles and abstracts provide accurate and concise information on an article's contents, their brevity inevitably entails the loss of detail. Full-text articles provide those details, but require more time to read. The primary goal of this study is to combine the advantages of concise abstracts and detail-rich full-texts to ease the burden of reading. RESULTS: We retrieved abstract-related paragraphs from full-text articles through shared keywords between the abstract and paragraphs from the main text. Significant paragraphs were then recommended by applying a proposed paragraph ranking approach. Finally, the user was provided with a condensed text consisting of these significant paragraphs, allowing the user to save time from perusing the whole article. We compared the performance of the proposed approach with a keyword counting approach and a PageRank-like approach. Evaluation was conducted in two aspects: the importance of each retrieved paragraph and the information coverage of a set of retrieved paragraphs. In both evaluations, the proposed approach outperformed the other approaches. CONTACT: jchiang@mail.ncku.edu.tw.

Overview of BioCreative II gene normalization.

BACKGROUND: The goal of the gene normalization task is to link genes or gene products mentioned in the literature to biological databases. This is a key step in an accurate search of the biological literature. It is a challenging task, even for the human expert; genes are often described rather than referred to by gene symbol and, confusingly, one gene name may refer to different genes (often from different organisms). For BioCreative II, the task was to list the Entrez Gene identifiers for human genes or gene products mentioned in PubMed/MEDLINE abstracts. We selected abstracts associated with articles previously curated for human genes. We provided 281 expert-annotated abstracts containing 684 gene identifiers for training, and a blind test set of 262 documents containing 785 identifiers, with a gold standard created by expert annotators. Inter-annotator agreement was measured at over 90%. RESULTS: Twenty groups submitted one to three runs each, for a total of 54 runs. Three systems achieved F-measures (balanced precision and recall) between 0.80 and 0.81. Combining the system outputs using simple voting schemes and classifiers obtained improved results; the best composite system achieved an F-measure of 0.92 with 10-fold cross-validation. A 'maximum recall' system based on the pooled responses of all participants gave a recall of 0.97 (with precision 0.23), identifying 763 out of 785 identifiers. CONCLUSION: Major advances for the BioCreative II gene normalization task include broader participation (20 versus 8 teams) and a pooled system performance comparable to human experts, at over 90% agreement. These results show promise as tools to link the literature with biological databases.

GeneLibrarian: an effective gene-information summarization and visualization system.

BACKGROUND: Abundant information about gene products is stored in online searchable databases such as annotation or literature. To efficiently obtain and digest such information, there is a pressing need for automated information-summarization and functional-similarity clustering of genes. RESULTS: We have developed a novel method for semantic measurement of annotation and integrated it with a biomedical literature summarization system to establish a platform, GeneLibrarian, to provide users well-organized information about any specific group of genes (e.g. one cluster of genes from a microarray chip) they might be interested in. The GeneLibrarian generates a summarized viewgraph of candidate genes for a user based on his/her preference and delivers the desired background information effectively to the user. The summarization technique involves optimizing the text mining algorithm and Gene Ontology-based clustering method to enable the discovery of gene relations. CONCLUSION: GeneLibrarian is a Java-based web application that automates the process of retrieving critical information from the literature and expanding the number of potential genes for further analysis. This study concentrates on providing well organized information to users and we believe that will be useful in their researches. GeneLibrarian is available on http://gen.csie.ncku.edu.tw/GeneLibrarian/.