43 research outputs found
The Square Root Problem and Subnormal Aluthge Transforms of Recursively Generated Weighted Shifts
For recursively generated shifts, we provide definitive answers to two
outstanding problems in the theory of unilateral weighted shifts: the
Subnormality Problem ({\bf SP}) (related to the Aluthge transform) and the
Square Root Problem ({\bf SRP}) (which deals with Berger measures of subnormal
shifts). We use the Mellin Transform and the theory of exponential polynomials
to establish that ({\bf SP}) and ({\bf SRP}) are equivalent if and only if a
natural functional equation holds for the canonically associated Mellin
transform. For --atomic measures with , our main result provides a
new and simple proof of the above-mentioned equivalence. Subsequently, we
obtain an example of a --atomic measure for which the equivalence fails.
This provides a negative answer to a problem posed by G.R. Exner in 2009, and
to a recent conjecture formulated by R.E. Curto et al in 2019
Public Procurement Crisis of Iraq and its Impact on Construction Projects
The public procurement crisis in Iraq plays a fundamental role in the delay in the implementation of construction projects at different stages of project bidding (pre, during, and after). The procurement system of any country plays an important role in economic growth and revival. The paper aims to use the fuzzy logic inference model to predict the impact of the public procurement crisis (relative importance index and Likert scale) was carried out at the beginning to determine the most important parameters that affect construction projects, the fuzzy analytical hierarchy process (FAHP) to set up, and finally, the fuzzy decision maker's (FDM) verification of the parameter for comparison with reality. Sixty-five construction projects in Iraq have been selected, and the most crucial crisis variables were used for calculating the weights and their importance, using the fuzzy logic inference model to verify the crisis parameters and the extent of their impact in preparation for predicting the mathematical model of public procurement parameters. After the algorithm had been completed, it was noted that the fast, messy genetic algorithm produced a little difference between training and testing (0.012% and 0.0057%), which is more reliable for predicting mean results from models. The paper’s major conclusion is that 18 crisis factors in public procurement through different stages affect construction projects in Iraq.
Fatigue Characterization Of A High-Performance Steel Fiber Reinforced Concrete (HPFRC) By Means Of Compressive, Flexural, And Z-Type Shear Tests
The use of fiber-reinforced concretes (FRC) for infrastructures subject to fatigue loading can result into an extension of their service life by providing enhanced ductility and toughness. The cyclic actions might affect the fiber-matrix interface and it is necessary to assess to what extent the degradation hinders the mechanical properties of these materials. Currently, the only predictive models for fatigue life and performance reduction are empirical. Therefore, a mechanical characterization is required for any mix whose composition and performance might differ from the one pertinent to the database the models are based on. This work presents the effect of high-cycle fatigue on a high-performance fiber-reinforced concrete (HPFRC) with hybrid fiber reinforcement. The material was characterized under compressive, flexural, and shear loads at various stress ranges. The Palmgren-Miner rule was applied to predict the fatigue life of the material. The results showed the effects of fatigue loading on the strength of the material. The compressive strength remained constant in most cases, while the flexural and the shear performances were slightly reduced by the cycling process. The predictive capacity of the P-M model proved to be reliable only in limited scenarios
Dose response for Auricularia auricula-judae against acute gamma irradiation
Auricularia auricula-judae is a jelly and ear-like mushroom well known as part of traditional Chinese medicine and cuisine.
Issues in mushroom cultivation are related to sustaining sufficient amount of strains with genetic variations for selection and
obtaining quality strains for mother cultures. Strain selections by growers are hampered by the narrow genetic variations of
existing mushrooms. Induced mutations through gamma radiation was found to significantly generate genetic variations in
mushroom. This study aims to determine dose response of A. auricula-judae when irradiated with gamma radiation. Samples
grown on semi solid PDA (Potato Dextrose Agar) media were exposed to gamma radiation from Cs-137 source in Biobeam
GM8000. Doses for acute gamma irradiation ranged from 0 Gy, 0.1 kGy, 0.2 kGy, 0.3 kGy, 0.4 kGy, 0.5 kGy, 0.6 kGy, 0.7
kGy, 0.8 kGy, 0.9 kGy, 1.0 kGy, 1.5 kGy, 2.0 kGy and 4.0 kGy at dose rate 0.013 kGy/min. Visual observations and
diameter growth measurements of mycelia were observed 2 days’ interval for 8 days. Results revealed mycelia density and
growth performance decreases with increasing radiation doses. Other morphological characters of irradiated mycelia remained
the same with control. LD50 for A. auricula-judae was determined at 1.5 kGy. Findings in this study are important for
induced mutation studies of A. auricula-judae and benefiting to the mushroom industry
Prevalence of Breast Tumors and Methods of Prevention: A Cross-sectional Study
Background: Breast cancer is one of the most prevalent forms of cancer in women and one of the most severe and significant public health concerns in developing nations. This study aimed to determine the prevalence of breast tumors and women’s preventive behavior. Methods: A descriptive, correlational cross-sectional design was employed for this study. The study was conducted at (jeddah). Participants were selected during the period from September to November 2022. Population of this study were adult women (Aged >18 years) at KSA. Study instruments consisted of the following domains sociodemographic data, anthropometric measurements, information related to menstrual cycle and pregnancy, obstetric history, family history, practices of breast self-examination, procedures of early detection and knowledge, attitude and practice assessment for methods of prevention. Results: The study included 420 women of different ages. Breast cancer was found among 82 women (19.5%). The mean age among all study participants was 33.96 + 14.79 years with median age of 28 years. More than half of study participants had normal BMI (n= 220, 52.4%) while third participants were overweight (n= 136, 32.4%). Among participants, 18.1% had a history of post-partum complications, 38.3% had undergone previous surgery, 1.4% had experienced vascular moles, 18.6% had a history of fibroid uterus, 6% had cervical polyps, and 5% had endometriosis. Table 3 presents obstetric history among study participants. More than half of study participants underwent previous hysteroscopy (n= 235, 56%). On the other hand, 81 women had a family history of breast cancer (19.3%). Most of women in this study perform self-examination of the breast (n= 300, 71.4%) and 102 women underwent fine needle aspiration procedure (FNA) (24.3%). The FNA result was positive among 81 women. Furthermore, 124 women underwent mammography (29.5%) and the result was positive among 67 participants. Breast cancer is found among 82 women (19.5%). Women in this study agreed that they should have clinical breast examination at any time (n= 191, 45.5%) while other women believed they should have this examination in certain circumstances such as mastodynia (n= 61, 14.5%), history of benign breast tumors (n= 38, 9%), obesity (n= 37, 8.8%) and family history of breast cancer (n= 32, 7.6%). Conclusion: Breast cancer prevalence was 19.5%. Urban residency was predominant, with varying educational levels. Marital status, income, family size, and work differed among participants. Chronic conditions and diverse anthropometric measurements were observed. Obstetric history showed early marriage and delivery ages, limited abortions, and varied complications. Family history indicated links to chronic diseases and cancers. Participants exhibited awareness about breast cancer risk factors and methods for early detection
Further insights into Caprine Arthritis Encephalitis (CAE): the current status of seroprevalence among small ruminants in two selected states of Peninsular Malaysia
Caprine arthritis-encephalitis virus (CAEV) is a member of the genus lentivirus causing caprine arthritis-encephalitis (CAE), a chronic inflammatory condition affecting the lungs, joints, udder and central nervous system of small ruminants such as sheep and goats.
CAE is distributed worldwide and is recognised as a significant cause of morbidity and decreased milk production in dairy goats. Earlier studies highlighted the clinicopathological features and supplied preliminary serological evidence for the existence of CAE among selected goat herds in Malaysia. Therefore, this study aims to provide further insights into the seroprevalence and contributing factors of CAE among sheep and goat herds in two states of Peninsular Malaysia. The blood samples and biodata were randomly collected from a total of 262 individual sheep (40) and goat (222) in seven smallholder farms. Blood sera were tested for specific anti-CAEV antibodies using Qayee-Bio CAEV sandwich-ELISA
test kits according to standard procedures. Our results of the study revealed 21.4% (95% CI: 15.8–28.6) apparent and 20.6% (95% CI: 14.5–27.8) true seroprevalence with significant differences (p < 0.05) in seroconversion rates between the states, farms, production systems
and breeds of small ruminants. The prevalence of CAE in the Malaysian Peninsular is a potential threat to the small ruminant industry and developing agricultural economy. Further studies are required to determine the genetic characteristics, distribution and risk factors of CAEV for effective prevention and control in Malaysia
Effects of a high-dose 24-h infusion of tranexamic acid on death and thromboembolic events in patients with acute gastrointestinal bleeding (HALT-IT): an international randomised, double-blind, placebo-controlled trial
Background: Tranexamic acid reduces surgical bleeding and reduces death due to bleeding in patients with trauma.
Meta-analyses of small trials show that tranexamic acid might decrease deaths from gastrointestinal bleeding. We
aimed to assess the effects of tranexamic acid in patients with gastrointestinal bleeding.
Methods: We did an international, multicentre, randomised, placebo-controlled trial in 164 hospitals in 15 countries.
Patients were enrolled if the responsible clinician was uncertain whether to use tranexamic acid, were aged above the
minimum age considered an adult in their country (either aged 16 years and older or aged 18 years and older), and
had significant (defined as at risk of bleeding to death) upper or lower gastrointestinal bleeding. Patients were
randomly assigned by selection of a numbered treatment pack from a box containing eight packs that were identical
apart from the pack number. Patients received either a loading dose of 1 g tranexamic acid, which was added to
100 mL infusion bag of 0·9% sodium chloride and infused by slow intravenous injection over 10 min, followed by a
maintenance dose of 3 g tranexamic acid added to 1 L of any isotonic intravenous solution and infused at 125 mg/h
for 24 h, or placebo (sodium chloride 0·9%). Patients, caregivers, and those assessing outcomes were masked to
allocation. The primary outcome was death due to bleeding within 5 days of randomisation; analysis excluded patients
who received neither dose of the allocated treatment and those for whom outcome data on death were unavailable.
This trial was registered with Current Controlled Trials, ISRCTN11225767, and ClinicalTrials.gov, NCT01658124.
Findings: Between July 4, 2013, and June 21, 2019, we randomly allocated 12 009 patients to receive tranexamic acid
(5994, 49·9%) or matching placebo (6015, 50·1%), of whom 11 952 (99·5%) received the first dose of the allocated
treatment. Death due to bleeding within 5 days of randomisation occurred in 222 (4%) of 5956 patients in the
tranexamic acid group and in 226 (4%) of 5981 patients in the placebo group (risk ratio [RR] 0·99, 95% CI 0·82–1·18).
Arterial thromboembolic events (myocardial infarction or stroke) were similar in the tranexamic acid group and
placebo group (42 [0·7%] of 5952 vs 46 [0·8%] of 5977; 0·92; 0·60 to 1·39). Venous thromboembolic events (deep vein
thrombosis or pulmonary embolism) were higher in tranexamic acid group than in the placebo group (48 [0·8%] of
5952 vs 26 [0·4%] of 5977; RR 1·85; 95% CI 1·15 to 2·98).
Interpretation: We found that tranexamic acid did not reduce death from gastrointestinal bleeding. On the basis of our
results, tranexamic acid should not be used for the treatment of gastrointestinal bleeding outside the context of a
randomised trial
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection