Amplitude and Phase Classification of ECG data

A functional data analysis approach to heart defect detection using heart signals recorded by electrocardiograms (ECGs) is proposed. ECGs can be thought of as continuous functions having an amplitude and phase component. However, raw heart signals are usually noisy with artifacts such as baseline wander and there are also issues with arbitrary location and scale when comparing two or more ECGs. To remove these artifacts, we propose amplitude registration models and give closed form solutions for the estimated parameters. For the classification of subjects, we propose to fit mixture Gaussian and cubic spline parametric models (which contain both amplitude and phase components) to the ECG functions. For heart conditions characterised by amplitude changes such as high peaks or inverted curves, classification is done using the estimated amplitude parameters. However, when conditions are characterised by changes in time domain, classification is done using the estimated phase parameters. The predictive accuracy of our proposed approach using leave-one-out cross-validation is 91% for the amplitude classification of myocardial infarction and 96% for the phase classification of cardiomyopathy. Our results compare favourably with state-of-the-art approaches for the classification of ECGs. Additionally, the proposed approach is applicable to the classification of other periodic biosignals

Emotional persistence in online chatting communities

How do users behave in online chatrooms, where they instantaneously read and write posts? We analyzed about 2.5 million posts covering various topics in Internet relay channels, and found that user activity patterns follow known power-law and stretched exponential distributions, indicating that online chat activity is not different from other forms of communication. Analysing the emotional expressions (positive, negative, neutral) of users, we revealed a remarkable persistence both for individual users and channels. I.e. despite their anonymity, users tend to follow social norms in repeated interactions in online chats, which results in a specific emotional "tone" of the channels. We provide an agent-based model of emotional interaction, which recovers qualitatively both the activity patterns in chatrooms and the emotional persistence of users and channels. While our assumptions about agent's emotional expressions are rooted in psychology, the model allows to test different hypothesis regarding their emotional impact in online communication.Comment: 34 pages, 4 main and 12 supplementary figure

Comparative algological and bacteriological examinations on biofilms developed on different substrata in a shallow soda lake

According to the European Water Framework Directives, benthic diatoms of lakes are a tool for ecological status assessment. In this study, we followed an integrative sample analysis approach, in order to find an appropriate substratum for the water qualification-oriented biomonitoring of a shallow soda lake, Lake Velencei. Six types of substrata (five artificial and one natural), i.e., andesite, granite, polycarbonate, old reed stems, Plexiglass discs and green reed, were sampled in May and in November. We analysed total alga and diatom composition, chlorophyll a content of the periphyton, surface tension and roughness of the substrata and carbon source utilisation of microbial communities. Water quality index was calculated based on diatom composition. Moreover, using a novel statistical tool, a self-organising map, we related algal composition to substratum types. Biofilms on plastic substrates deviated to a great extent from the stone and reed substrata, with regard to the parameters measured, whereas the biofilms developing on reed and stone substrata were quite similar. We conclude that for water quality monitoring purposes, sampling from green reed during springtime is not recommended, since this is the colonization time of periphyton on the newly growing reed, but it may be appropriate from the second half of the vegetation period. Stone and artificially placed old reed substrata may be appropriate for biomonitoring of shallow soda lakes in both spring and autumn since they showed in both seasons similar results regarding all measured features

Breast cancer incidence following low-dose rate environmental exposure: Techa River Cohort, 1956–2004

In the 1950s, the Mayak nuclear weapons facility in Russia discharged liquid radioactive wastes into the Techa River causing exposure of riverside residents to protracted low-to-moderate doses of radiation. Almost 10 000 women received estimated doses to the stomach of up to 0.47 Gray (Gy) (mean dose=0.04 Gy) from external γ-exposure and 137Cs incorporation. We have been following this population for cancer incidence and mortality and as in the general Russian population, we found a significant temporal trend of breast cancer incidence. A significant linear radiation dose–response relationship was observed (P=0.01) with an estimated excess relative risk per Gray (ERR/Gy) of 5.00 (95% confidence interval (CI), 0.80, 12.76). We estimated that approximately 12% of the 109 observed cases could be attributed to radiation

Radiation-induced malignancies following radiotherapy for breast cancer

With advances in diagnosis and treatment, breast cancer is becoming an increasingly survivable disease resulting in a large population of long-term survivors. Factors affecting the quality of life of such patients include the consequences of breast cancer treatment, which may have involved radiotherapy. In this study, we compare the incidence of second primary cancers in women who received breast radiotherapy with that in those who did not (non-radiotherapy). All women studied received surgery for their first breast cancer. Second cancers of the lung, colon, oesophagus and thyroid gland, malignant melanomas, myeloid leukaemias and second primary breast cancers were studied. Comparing radiotherapy and non-radiotherapy cohorts, elevated relative risks (RR) were observed for lung cancer at 10-14 years and 15 or more (15+) years after initial breast cancer diagnosis (RR 1.62, 95% confidence interval [CI] 1.05-2.54 and RR 1.49, 95% CI 1.05-2.14, respectively), and for myeloid leukaemia at 1-5 years (RR 2.99, 95% CI 1.13-9.33), for second breast cancer at 5-10 years (RR 1.34, 95% CI 1.10-1.63) and 15+ years (RR 1.26, 95% CI 1.00-1.59) and oesophageal cancer at 15+ years (RR 2.19, 95% CI 1.10-4.62)

Priorities in Chronic nonbacterial osteomyelitis (CNO) - results from an international survey and roundtable discussions

ObjectiveChronic nonbacterial osteomyelitis (CNO) is an autoinflammatory bone disorder that predominantly affects children and young people. The pathophysiology and molecular mechanisms of CNO remain poorly understood, and diagnostic criteria and biomarkers are lacking. As a result, treatment is empiric and follows personal experience, case series and expert consensus plans.MethodsA survey was designed to gain insight on clinician and patient experiences of diagnosing and treating CNO and to collate opinions on research priorities. A version containing 24 questions was circulated among international expert clinicians and clinical academics (27 contacted, 21 responses). An equivalent questionnaire containing 20 questions was shared to explore the experience and priorities of CNO patients and family members (93 responses).ResultsResponses were used to select topics for four moderated roundtable discussions at the "International Conference on CNO and autoinflammatory bone disease" (Liverpool, United Kingdom, May 25-26th, 2022). The group identified deciphering the pathophysiology of CNO to be the highest priority, followed by clinical trials, necessary outcome measures and classification criteria. Surprisingly, mental wellbeing scored behind these items.ConclusionsAgreement exists among clinicians, academics, patients and families that deciphering the pathophysiology of CNO is of highest priority to inform clinical trials that will allow for the approval of medications for the treatment of CNO by regulatory agencies

Soya foods and breast cancer risk: a prospective study in Hiroshima and Nagasaki, Japan

The association between soya foods and breast cancer risk was investigated in a prospective study of 34 759 women in Hiroshima and Nagasaki, Japan. Women completed dietary questionnaires in 1969–1970 and/or in 1979–1981 and were followed for incident breast cancer until 1993. The analysis involved 427 cases of primary breast cancer in 488 989 person-years of observation. The risk for breast cancer was not significantly associated with consumption of soya foods: for tofu, relative risks adjusted for attained age, calendar period, city, age at time of bombings and radiation dose to the breast were 0.99 (95% CI 0.80–1.24) for consumption two to four times per week and 1.07 (0.78–1.47) for consumption five or more times per week, relative to consumption once a week or less; for miso soup, relative risks were 1.03 (0.81–1.31) for consumption two to four times per week and 0.87 (0.68–1.12) for consumption five or more times per week, relative to consumption once a week or less. These results were not materially altered by further adjustments for reproductive variables and were similar in women diagnosed before age 50 and at ages 50 and above. Among 17 other foods and drinks examined only dried fish (decrease in relative risk with increasing consumption) and pickled vegetables (higher relative risk with higher consumption) were significantly related to breast cancer risk; these associations were not prior hypotheses and, because of the large number of comparisons made, they may be due to chance. © 1999 Cancer Research Campaig

Sex differential in mortality trends of old-aged Danes: a nation wide study of age, period and cohort effects

Objective Over the last half century the mortality rates in Denmark for females above age 80 have declined dramatically whereas the decline for males have been modest, resulting in a change in sex-ratio for centenarians from 2 to 5. Here we investigate whether this mortality pattern is mainly explained by period effects, cohort effects or both. This can provide clues for where to search for causes behind the changes in sex differential in mortality seen in many Western countries during the last decades. Methods Age-period-cohort study of mortality for all Danish women and men aged 79–98 during the period 1949–2006. Outcome measures Relative risks for deaths and second order differences for exploration of the nonlinear variation. Results Both the overall trends in mortality differences and the fluctuations in mortality for both men and women were better explained by period effects than by cohort effects. The observed rates were better described by the age, period and cohort model than by other models. Conclusions Our results suggest that causes for both the overall increased difference in mortality and the short term fluctuations in mortality rates are primarily to be found in the period dimension. Cohort effects on the mortality of the oldest Danish women and men played a significant but minor role compared to period effects