A Scalable Post-quantum Hash-Based Group Signature

Abstract. We present a construction for hash-based one-time group signature schemes, and develop a traceable post-quantum multi-time group signature upon it. A group signature scheme allows group members to anonymously sign a message on behalf of the whole group. The signatures are unforgeable and the scheme enables authorized openers to trace the signature back to the original signer when needed. Our construction utilizes three nested layers to build the group signature scheme. The first layer is key management; it deploys a transversal design to assign keys to the group members and the openers, providing the construction with traceability. The second layer utilizes hash pools to build the group public verification key, to connect group members together, and to provide anonymity. The final layer is a post-quantum hash-based signature scheme, that adds unforgeability to our construction. We extend our scheme to multi-time signatures by using Merkle trees, and show that this process keeps the scalability property of Merkle-based signatures, while it supports the group members signing any number of messages. Keywords: Post Quantum Signatures, Hash-based Signatures, Group Signatures, Transversal Designs, Multi-opener Signature

PREVALENCE OF PATENT FORAMEN OVALE IN YOUNG PATIENTS WITH CRYPTOGENIC ISCHEMIC STROKE

Abstract &nbsp;&nbsp; BACKGROUND: Patent foramen ovale (PFO) is the most commonly persistent abnormality of fetal origin. PFO has long been recognized as a potential risk factor for ischemic stroke. This study has shown the prevalence of PFO among young patients with cryptogenic stroke. &nbsp;&nbsp; METHODS: In our case-control study we had 32 patients, 18 to 55 years old with cryptogenic stroke and 64 participants among normal population with matched age and sex in control group. We studied them for stroke risk factors like hypertension, diabetes mellitus, ischemic heart disease, dyslipidemia and then election of PFO by contrast trans-thoracic echocardiography. Data entered in SPSS11 and analyzed by Chi-Square and logistic regression. P value less than 0.05 was considered statistically significant. &nbsp;&nbsp; RESULTS: We found that 37.5 % of patients in case group and 7.7 % of patients in controls had PFO and this difference was statistically significant (P = 0.001). They had no significant difference in other atherosclerosis risk factors. In control group we saw small shunt but in stroke group large shunt was more prevalence (P &lt; 0.05).&nbsp; &nbsp;&nbsp; CONCLUSION: Our findings supported this idea that PFO is a predisposing factor for stroke and it had a higher prevalence among patients with cryptogenic stroke. Besides, large shunt was more concomitant with ischemic attack. Then we suggest any patient with undefined cause of stroke must be evaluated for PFO. &nbsp; &nbsp;&nbsp; Keywords: Patent foramen ovale, Stroke, Young. &nbsp;</p

Diagnostic and predictive value of coronary artery calcification in coronary artery stenosis

BACKGROUND: Early diagnosis of coronary artery diseases (CADs) may lead to more efficient treatments. Coronary artery calcification is considered as a valuable index in detecting CAD using a noninvasive technique. This study was conducted to determine the correlation between coronary artery calcification and coronary artery stenosis in patients with typical chest pain.METHODS: This cross-sectional study was conducted on 760 patients suffering from typical chest pain, in Chamran Hospital, Isfahan, Iran. The patients&nbsp; were all candidates for coronary angiography and were studied for the calcification of coronary artery by fluoroscopy. All patients signed a consent form after the whole procedures were fully explained to them. A fluoroscopic movie was taken from patients (after exposing, and before inserting the angiographic catheter), then the angiography was conducted using Judkins technique.&nbsp; The results of fluoroscopy and angiography were recorded by two cardiologists separately. The presence of any significant stenosis greater than 75% was considered as a sign of severe CAD. The data was analyzed by chi-square test.RESULTS: Abnormal angiogram was found in 402 patients (59.2%). Positive and negative predictive values for calcification were 81.8% and 26%, respectively. Positive and negative predictive values were respectively 87.1% and 63.4% in females, and 79.7% and 47.3% in males. The highest predictive value (100%) was seen in patients under 40 years old. Coronary calcification in patients with abnormal coronary angiogram was found to be 5.4 times greater than those with normal angiogram.&nbsp;CONCLUSION: Considering the high predictive value of coronary artery calcification in fluoroscopy, it can be used as a replacement for screening coronary involvement.Keywords: Calcification, Coronary Vessels, Coronary Disease, Diagnosis</p

Quality of life, religious attitude and cancer coping in a sample of iranian patients with cancer

BACKGROUND: Cancer is one of the leading causes of mortality and morbidity worldwide. The incidence of cancer has increased markedly in recent decades in most countries. Studies have shown that diseases such as cancer affect the individuals' quality of life. METHODS: The sample of study consisted of 384 patients selected through non-random convenient sampling procedure from three general hospitals and outpatient clinics in Isfahan and Tehran. The measures used in the study included a demographic questionnaire, the Iranian version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30), the Cancer Coping Questionnaire, and the Religious Attitude Questionnaire. RESULTS: The results revealed significant correlation between patients' scores on the total scale of the Cancer Coping Questionnaire and their scores on the Global health status/Quality of Life. Significant correlations were also found between patients' scores on the Religious Attitude Questionnaire and various scales of the Quality of Life Questionnaire. However, no significant correlations were found between Cancer Coping and Religious Attitude measures in any type of cancer except for the prostate cancer. CONCLUSIONS: Religious attitude was a significant and important factor in coping with cancer. In addition, patients' quality of life correlated significantly with religious attitude as well as cancer coping measures. However, the results did not show any significant relationship between religious attitude and cancer coping measures except in patients with prostate cancer. The findings of this study are consistent with other studies that have shown significant correlations between religiosity and spirituality and quality of life in patients with life threatening diseases

The study of mutation in 23S rRNA resistance gene of Helicobacter pylori to clarithromycin in patients with gastrointestinal disorders in Isfahan - Iran

Background: Helicobacter pylori antimicrobial resistance is an important factor responsible for treatment failure. The purpose of this study was evaluating the prevalence of point mutations in clarithromycin-resistant clinical isolates of H. pylori in Isfahan city of Iran. Materials and Methods: Thirty isolates of H. pylori from 130 biopsy specimens were isolated by culture and confirmed by biochemical and PCR tests. The MIC of clarithromycin antibiotic for 30 clinical isolates of H. pylori was determined by E-test method. The point mutations in the 288 bp of 23S rRNA gene of H. Pylori were investigated in four clarithromycin-resistant clinical isolates by PCR followed by sequencing. Results: Among 30 isolates of H. pylori, 4 cases were resistant to clarithromycin. One point mutation was found at position T2243C in the 23S rRNA gene in all resistance isolates. Conclusions: In our study, H. pylori resistance to clarithromycin associated with point mutation at position 2243 (T2243C)

Evaluating the Causes of Deductions for Inpatient Bills Covered by Social Security Insurance in Rofeideh Hospital, Tehran City, Iran, in 2021

Objective Insurance deductions are among the most important causes of hospital resource waste. Insurance deductions cause financial problems for hospitals and create tension between insurance organizations and hospitals. This study, done by the University of Social Welfare and Rehabilitation Sciences, investigates the reasons for deductions of inpatient bills covered by Social Security Insurance in Rofeideh Rehabilitation Hospital Materials & Methods The study was conducted cross-sectionally on 776 cases admitted to Rofeidah Rehabilitation Hospital in 2021. All invoices for inpatient services sent to Social Security Insurance were reviewed using the census method. To collect data, invoices sent to Social Security, inpatient records and checklists, and a 31-question questionnaire of Mohammadkhani et al. were used. The collected data were analyzed by descriptive (frequency and percentage) and analytical statistics (the Spearman correlation coefficient) in SPSS software, version 23. Results According to the findings, the highest frequency of inpatient prescriptions was related to November 2021 (7.48%). The most frequent deductions of inpatients’ bills were related to medicine and consumables to the amount of 310815448 Rails and surgeon’s fees in 187728448 Rails. Also, the most common reasons were requesting a surcharge and wrong coding. In this study, there was a significant relationship between the documentation of nurses and doctors and the amount of deductions (P<0.0001). Conclusion Multiple causes affect the reduction of insurance deductions. By teaching insurance rules and the book on the relative value of health services to medical and nursing staff groups, electronic documents to Social Security Insurance and creating warning mechanisms in it, continuous interaction with Social Security Insurance to justify the managers of the organization regarding the way of providing services to rehabilitation patients and the reason for the prolonged hospitalization time of such patients could be the potential solutions for preventing patients records deductions and help hospitals achieve financial goals

Sleep movements and respiratory coupling as a biobehavioral metric for early Alzheimer’s disease in independently dwelling adults

Abstract Introduction Sleep disorder is often the first symptom of age-related cognitive decline associated with Alzheimer’s disease (AD) observed in primary care. The relationship between sleep and early AD was examined using a patented sleep mattress designed to record respiration and high frequency movement arousals. A machine learning algorithm was developed to classify sleep features associated with early AD. Method Community-dwelling older adults (N = 95; 62–90 years) were recruited in a 3-h catchment area. Study participants were tested on the mattress device in the home bed for 2 days, wore a wrist actigraph for 7 days, and provided sleep diary and sleep disorder self-reports during the 1-week study period. Neurocognitive testing was completed in the home within 30-days of the sleep study. Participant performance on executive and memory tasks, health history and demographics were reviewed by a geriatric clinical team yielding Normal Cognition (n = 45) and amnestic MCI-Consensus (n = 33) groups. A diagnosed MCI group (n = 17) was recruited from a hospital memory clinic following diagnostic series of neuroimaging biomarker assessment and cognitive criteria for AD. Results In cohort analyses, sleep fragmentation and wake after sleep onset duration predicted poorer executive function, particularly memory performance. Group analyses showed increased sleep fragmentation and total sleep time in the diagnosed MCI group compared to the Normal Cognition group. Machine learning algorithm showed that the time latency between movement arousals and coupled respiratory upregulation could be used as a classifier of diagnosed MCI vs. Normal Cognition cases. ROC diagnostics identified MCI with 87% sensitivity; 89% specificity; and 88% positive predictive value. Discussion AD sleep phenotype was detected with a novel sleep biometric, time latency, associated with the tight gap between sleep movements and respiratory coupling, which is proposed as a corollary of sleep quality/loss that affects the autonomic regulation of respiration during sleep. Diagnosed MCI was associated with sleep fragmentation and arousal intrusion