Minimal Risk Research Articles

УПРАВЛІННЯ РИЗИКАМИ ДОРОЖНЬОГО БУДІВНИЦТВА

The development of the road network plays a key role in the social, economic and environmental development of a country, region cities. A key aspect for achieving the set goals and ensuring the sustainability and efficiency of road construction projects is the management of risks that arise during project planning and execution. The purpose of the work is the research and classification of risks that arise during the implementation of road construction projects, the formation of a risk management system and the search for ways to minimize their negative consequences. The paper proposes a road construction risk management mechanism, the main purpose of which is to ensure the successful implementation of the road construction project, taking into account all possible risks that may affect the process of its implementation and results. The classification of road construction risks by origin, nature, stages of the project, impact on participants, scale, which will ensure the identification of potential risks, the probability of their occurrence and the establishment of the scale of consequences from their impact, is considered. The successful implementation of road construction projects is ensured by measures to minimize the negative consequences of the impact of risks. The authors identified the main areas of risk minimization during road construction, including detailed planning, risk analysis, use of technologies and innovations, reserve time planning, quality control, stakeholder participation, insurance, environmental management, creation of reserve funds, contingency scenario or plans. A contingency scenario of risk minimization in road construction is proposed, which makes it possible to define measures and strategies for the active management of risks that may arise during a road construction project. A contingency scenario allows you to prepare for unforeseen circumstances and negative events that may occur during the implementation of a road construction project. The application of this scenario is absolutely necessary in cases where there is a high probability of the occurrence of specific risks or when these risks can have a serious impact on the project

8550 Processing Technique Affects Aromatase Expression in Fat Grafts for Breast Reconstruction

Abstract Disclosure: S. Arbuiso: None. Y. Chen: None. N.A. Vernice: None. A. Zhang: None. I.J. Rhodes: None. C.C. Alston: None. S. Hanif: None. S. Liu: None. P. Bhardwaj: None. D. Janhofer: None. G.G. Black: None. D.M. Otterburn: None. K.A. Brown: None. Introduction: Autologous fat grafting is commonly used in breast reconstruction as it is associated with good cosmetic outcomes, high patient satisfaction, and minimal risks. Adipose tissue is known to support cancer growth via the secretion of adipokines and the modulation of estrogen levels due to aromatase expressed in adipose stromal cells. A higher body mass index (BMI) and postmenopausal status are associated with higher levels of aromatase. With novel processing techniques being developed to increase fat graft retention, there is a need to better understand how these will affect the biology of lipoaspirates for women who have previously had breast cancer. This study aims to assess how different processing techniques used in fat grafting (1) impact aromatase gene expression, (2) affect breast cancer cell proliferation, and (3) affect the cellular composition of the engrafted lipoaspirate. Methods: Patients who underwent breast reconstruction for breast cancer treatment or for prophylactic measures, and were receiving autologous fat grafting, were enrolled in a prospective randomized controlled trial (NCT04891510). Patients were randomized to one of three processing techniques: standard decantation, active filtration, and low-pressure decantation. Conditioned media (CM) was created from each sample. Aromatase mRNA was measured in the lipoaspirate using qRT-PCR for aromatase (CYP19A1) and related to patient BMI or menopausal status. The effect of CM on the proliferation of MCF7 cells (estrogen receptor positive (ER+) breast cancer cell line) was measured using CyQUANT. Formalin-fixed lipoaspirate samples were embedded in HistoGel and paraffin. Adipocyte diameter was measured in hematoxylin and eosin (H&E) stained sections using ImageJ. Results: Aromatase mRNA levels were correlated with BMI and were higher in postmenopausal women (p≤0.05), with the standard decantation group demonstrating a stronger correlation with BMI. Samples processed via active filtration were associated with weaker correlations between aromatase gene expression and BMI and menopausal status. CM induced MCF7 cell proliferation to a similar extent to cells plated in fetal bovine serum-containing media. There was no difference in proliferation patterns between treatment groups. Upon histological assessment, adipocytes were intact, and adipocyte diameter was significantly correlated with patient BMI. Conclusion: Lipoaspirate may contain factors that promote breast cancer cell proliferation, unaffected by processing technique. Caution should be used to ensure local control of the cancer has been achieved prior to reconstruction. Our data suggest that active filtration selects for a lower percentage of adipose stromal cells, which may be beneficial for patients who previously had ER+ breast cancer. Presentation: 6/1/2024

Techno-economic assessment of co-production of biodiesel and epoxy fatty acid methyl ester as renewable fuel and plasticizer from waste cooking oil

Diversifying waste cooking oil (WCO)-based biodiesel production towards epoxy fatty acid methyl esters (EFAMEs) offers a double gain, boosting revenue channels in the biodiesel sector and driving the development of sustainable phthalate plasticizer alternatives. This study explored the techno-economic feasibility of co-derived biodiesel and EFAMEs from WCO using a three-step process involving enzymatic transesterification, urea complexation, and performic acid epoxidation. The result shows that a plant processing 61,300 tonnes/year of WCO, may produce ∼27,770 tonnes/year of biodiesel and ∼30,180 tonnes/year of EFAMEs, with a total heating duty of 1,124 kW and annual electricity consumption of 34.9 million kWh. The initial capital investment of the plant in China amounts to 136.8 MM CNY, with an annual manufacturing cost of 460 MM CNY in 2022. Techno-economic evaluation demonstrats a net present value (NPV) of 421.9 MM CNY at a 10 % discount rate, an internal rate of return (IRR) of 37.69 %, and discounted payback period of 2.37 years. The break-even point (BEP) is estimated at an annual sales volume of total products of 27,101 tonnes/year, including 12,790, 11,769, 2,542, and 2,390 tonnes/year of epoxy plasticizers, biodiesel, glycerol, and polymeric grease, respectively, collectively utilizing 42.38 % of the processing capacity. Monte Carlo simulation indicates minimal risk of the project, with probabilities of 98.5 % for IRR > 10 % and 97.8 % for a positive NPV. This study affirms the economic viability of co-producing biodiesel and EFAMEs from WCO for industrial application.

A-011 Single High-Sensitivity Cardiac Troponin I Compared to High-Sensitivity Cardiac Troponin T Measurement to Rule Out Acute Myocardial Infarction at Low Risk for 30-Day Adverse Events: CONTRAST Study

Abstract Background Cardiac troponin (cTn) is the preferred biomarker for diagnosing myocardial injury and acute myocardial infarction (MI). There are few comparative studies addressing the clinical performance of high-sensitivity (hs)-cTnI and hs-cTnT assays using fresh plasma for early rule out of myocardial infarction (MI) on presentation in patients presenting to emergency departments (ED). This study examined the performance strategies of a derived optimal concentration for a single high-sensitivity cardiac troponin I (hs-cTnI) measurement compared to a derived optimal concentration for a single high-sensitivity cardiac troponin T (hs-cTnT) measurement to rule out acute MI. Methods The COmparisoN of high-sensitivity cardiac TRoponin I and T ASsays Trial (CONTRAST) (NCT03214029) is a prospective, observational cohort study of consecutive adult ED patients (n = 2208) undergoing serial cTn measurements as clinically indicated. hs-cTnI (Abbott ARCHITECT) and hs-cTnT (Gen 5, Roche e601) measurements using fresh EDTA plasma were obtained. We determine optimal hs-cTn cutoffs for negative predictive value (NPV) and sensitivity for the diagnosis of acute MI (type 1 and type 2) to allow for a maximum number for early discharges with minimal risk of adverse events (acute MI or cardiac death) at 30 days. Results Acute MI occurred in 161 patients (7.3%), including 68 (42.2%) type 1 MI and 93 (57.7%) type 2 MI. For hs-cTnI (<2 ng/L) optimal NPV and sensitivity for adverse events were 99.1% (95% confidence interval 97.7%-99.8%) and 98.2% (CI. 95.4-99.5%). 450 Patients (21%) qualified for early rule out, at a 1.8% miss rate at 30 days. For hs-cTnT (<6 ng/L) optimal NPV and sensitivity for adverse events were 99.2% (CI 98.0%-99.8%) and 98.1% (CI. 95.3-99.5%). 513 Patients (24%) qualified for early rule out, at a 1.9% miss rate at 30 days. Conclusions In CONTRAST, a strategy using a single sample hs-cTnI or hs-cTnT alone allows for the early identification of patients unlikely to have acute MI and who are at very low risk for adverse events at 30 days. Minor differences existed between the Abbott ARCHITECT hs-cTnI assay and the Roche e601 hs-cTnT (Gen 5) assay in fresh plasma were found.

Long-term cause-specific mortality in adolescent and young adult Hodgkin lymphoma patients treated with contemporary regimens-A nationwide Danish cohort study.

The documented treatment-induced excess mortality in Hodgkin lymphoma (HL) has spurred important treatment changes over recent decades. This study aimed to examine mortality among young HL patients treated with contemporary strategies, including historical data comparison. This nationwide study included 1348 HL patients, diagnosed in 1995-2015 and aged 15-40 at diagnosis. Among the patients, 66.5% had Ann Arbor stage I-II and 33.5% had stage III-IV disease. With a median follow-up of 14.76 years, 139 deaths occurred, yielding a 5-year overall survival of 94.6%. Older age, advanced disease, earlier treatment periods and extensive regimens were associated with higher overall mortality risk. The cumulative risk of HL-related death showed an initial sharp rise, with a plateau at 5.3% 10-year post-diagnosis. Deaths due to cardiovascular or pulmonary diseases and second cancers initially had minimal risk, gradually reaching 1.2% and 2.0% at the 20-year mark respectively. HL cases had a 7.5-fold higher mortality hazard than the background population. This study suggests that contemporary HL treatment still poses excess mortality risk, but recent changes have notably reduced overall and cause-specific mortality compared to earlier eras. Balancing treatment efficacy and toxicity remains crucial, but our findings highlight improved outcomes with modern treatment approaches.

COVID-19 vaccinations pre- and antepartum: a consideration of the evidence and discussion of issues.

The COVID-19 vaccine should be universally offered to pregnant women and women planning pregnancies. This is on the basis that COVID-19 infection can complicate the pregnancy and have adverse health implications in pregnancy, as compared to non-pregnant women, which the vaccine helps to mitigate. This is the recommendation of many governing bodies in medical care. However, certain issues require consideration, which are not discussed in the current guidelines. These include the induction of fever by the vaccines and the role fever can play in teratogenicity, the induction of hyper-coagulable and thrombocytopenic states by the vaccines and other known contraindications to the vaccines. In this article, we develop strategies to minimize risks in these situations. We also discuss the theoretical advantage of calling for a booster COVID-19 vaccinate in all pregnant women in the late second or early third trimester, even if previously immunized, and encourage further research, to investigate the possible benefits of this proposed intervention. This article acts as an educational supplement to help clinicians manage pregnant women and addresses many issues, not discussed in most COVID-19 vaccine recommendations by international societies related to pregnant women. This article is a literature review of the current, limited data. The information extrapolated allowed for suggestions regarding COVID-19 vaccination during pregnancy. RESULTSAND CONCLUSIONS: The study discusses hypothetical issues, to minimize any risks associated with COVID-19, and serves as a compilation of data to further the current literature, in proving that COVID-19 vaccines have minimal risks in pregnancy.

A new lattice approach for risk-minimization hedging under generalized autoregressive conditional heteroskedasticity models

This paper explores the calculation of risk-minimization hedging strategies, specifically local and global risk minimization strategies for contingent claims under affine and non-affine GARCH models with the known closed forms of its first four moments across times under the physical measure. A unified and efficient willow tree method is introduced for various GARCH models. Unlike methods that provide option values and hedging ratios solely at the inception time, the proposed willow tree method generates a comprehensive table of option values and hedging ratios at each discrete time step across possible asset prices. Additionally, the method showcases robust performance in hedging at lower frequencies than the underlying asset’s modeling frequency (e.g., weekly or monthly hedging using a daily GARCH model). Lastly, the willow tree method outperforms the Monte Carlo method, offering greater efficiency, accuracy, and flexibility in solving risk-minimization hedging problems.

Aggregated health risk assessment of perfluoroalkyl acids migrated from convenience food contact materials.

Ingestion of perfluoroalkyl acids (PFAAs) via contaminated food contact materials (FCMs) is an important human exposure source. This study adopts a toxicity equivalent approach to evaluate the collective health risk of multiple PFAAs in FCMs. A comprehensive extraction and analysis of 21 PFAAs in FCMs was performed. Among the analyzed substances, 15 PFAAs were detected. Migration experiment using three food simulants revealed the migration range of seven PFAAs from FCMs into the simulant to be 0.47-46.7ng/cm2. The hazard quotient results suggest minimal health risk, except for 9% of packaged samples where perfluorooctanoic acid (PFOA) poses a higher risk. Utilizing PFOA toxic equivalent concentrations, comprehensive risk calculations showed ∼77% of samples potentially posing elevated health risks due to PFAA exposure. This emphasizes the substantial contribution of PFAAs beyond PFOA and underscores the importance of considering them in related assessments. The aggregated risk assessment reflects actual exposure circumstances more accurately.

Evaluating Groundwater Quality for Drinking and Irrigation Purposes and Health Risk Assessment in West Midnapore District of West Bengal, India

Groundwater quality in the West Midnapore district of West Bengal, India is affected by anthropogenic activities as well as by water quality of Subarnarekha and Kangsabati rivers. This study aims to assess quality of groundwater and river water for drinking and irrigation usage, and assess the health risks of the people consuming the water across the rivers. The study also explores the groundwater-river water interaction. The river water and groundwater samples were collected three times during monsoon season from 14 sites across the rivers. The samples were analyzed for 11 water quality parameters, i.e., pH, total dissolved solids (TDS), total hardness (TH), major anions and cations, and iron (Fe). The groundwater was found slightly acidic (mean pH ~ 6.71) and correlated with nitrate concentrations. Most of the water quality parameters were found within their permissible limits of drinking water. However, elevated concentrations of potassium (K), ammonium (NH4), magnesium (Mg), phosphate (PO4), sodium (Na), and Fe were detected at some places, which were likely due to use of fertilizers. Water quality index (WQI), sodium absorption ratio (SAR), and percentage Na values were computed to evaluate the groundwater quality. The mean WQI value of 37.07 showed that the majority of groundwater samples met drinking water standards. Groundwater was also found suitable for irrigation (SAR ~ 0.26 to 1.62 meq L-1 and percentage Na ~ 13.10% to 78.12%). Health risk assessments suggested minimal immediate risks, though high Na levels in certain areas raised concerns. Piper plot showed that increased calcium concentrations in groundwater were mainly due to interactions between river water and groundwater. Overall, groundwater quality did not present any harmful health hazards to the community. The findings of this study can be instrumental for groundwater managers in identifying potential areas for treating groundwater quality.

Determination of Bisphenol A and its analogues in crayfish by UPLC-MS/MS and the assessment of dietary exposure of adults in Tianjin

Bisphenol A (BPA), an identified environmental endocrine disruptor, is under strict control due to its biotoxic effects. Alternatives to BPA, including Bisphenol F (BPF) and Bisphenol S (BPS), are progressively being developed and extensively utilized, with their potential health risks attracting heightened scrutiny. The objective of this study was to assess the exposure levels of BPA and its analogues (BPs) in crayfish and to evaluate the health effects related to crayfish consumption. Consequently, a robust ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the identification and quantification of BPs in crayfish. Furthermore, 96 crayfish samples purchased in Tianjin were obtained for analysis. The detection rate of BPA was 86.5 % in crayfish, with the maximum concentration of 31.3 µg/kg. BPS was found in 26.0 % of the samples, with the highest concentration at 33.1 μg/kg. Additionally, the levels of BPs in both abdominal muscle and hepatopancreas of the crayfish were determined. The results revealed a significantly higher concentration of BPA in the hepatopancreas compared to the abdominal muscle (P < 0.05). The total dietary intake of BPA through crayfish consumption was far below the tolerable daily intake (TDI) of 4 μg/kg body weight/day, suggesting minimal health risk associated with BPs exposure from crayfish consumption.

Age and Gender Related Changes on Total Antioxidant/Oxidant Status and Electrolyte Composition of Saliva in Individuals

BackgroundSaliva is used as an important biological material in the diagnosis and treatment of various diseases to collect easily, to be cheap, to have a minimal risk of infection. Here in that study we aimed to evaluate age and gender-related changes on total antioxidant/oxidant status and electrolyte composition of saliva levels in individuals. MethodsA total of 30 young adult (21.2± 2.47 years) and 14 adult (51.6±9.35 years) subjects were included in the study. Stimulated saliva samples were collected. Cortisol, amylase, oxidative stress biomarkers (total antioxidant status and total oxidant status) were measured by ELISA and spectrophotometric manual methods and electrolyte level of saliva samples were determined by autoanalyzer. ResultsSalivary concentrations of biomarkers of young adults were compared to adult subjects, there was a statistically significant difference between cortisol (μg/dL) (p=0.003), Ca+2(mg/dL) (p=0.004), TAS (mmol Trolox Equiv/L) (p=0.001), BUN (mg/dL) (p=0.02), Mg+2 (mg/dL) (p=0.02), and K+ (mmol/L) (p=0.05) levels , but there was no significant difference was found between uric acid (mg/dL) (p=0.44), Cl- (mmol/L) (p=0.07), amylase (ng/mL) (p=0.47), phosphate (mg/dL) (p=0.63), Na+(mmol/L)( p=0.21), and TOS (μmol H2O2 Equiv/L) ( p=0.70) levels. We evaluated salivary cortisol, amylase, and electrolyte levels of groups that we commented on their relationship between oxidant-antioxidant defense systems of the saliva and their correlations with age and gender. ConclusionsThis study could suggest the use of saliva samples to correlate with age and representing the levels of the most common biological parameters for routine use and antioxidant-oxidant enzymes for clinical trials.

A new quantitative method for determining patient risk for reusable medical device categorization based on using and interpreting Kremer’s cleaning classification system

The cleaning of reusable medical devices involves inherent challenges that can impact on the effectiveness of the cleaning process; consequently, the subsequent safety of patients. Fluid dynamics play a critical role in determining the flow and distribution of cleaning agents where the design of the device can either facilitate or hinder this important process. Complex geometries, narrow channels, or irregular surfaces can impede effective flushing of contaminants leading to incomplete cleaning that creates a greater likelihood for patient contamination risks. Device features (n =23) were exposed to the most challenging cleaning conditions to find the point of failure in both fluid dynamics and soil retention. Experimental results obtained from the aforementioned along with associated compound risks were used to assign a risk value. Using the "hardest to clean" device feature approach as the base risk value, the total quantitative risk score was calculated for different reusable medical devices from numerical values obtained from addressing 14 questions focusing on variability in geometry, material use, types of cleaning, and intended patient use. Patient risk values for devices with different features were calculated from using Kremer's cleaning categories based on position within value ranges. Occurrences less than 18 correspond to minimal risk devices while a total risk score between the values of 18-39 are moderate and equal to or above 40 scores corresponds to the maximal category. Application of this quantitative assessment approach will facilitate appropriate mitigation of risk for cleaning reusable medical devices by informing use of targeted effective interventions. Future use of this Kremer cleaning classification will complement and augment disinfection and sterilization modalities.

Diagnosis and management of spontaneous coronary artery dissection: Two cases and a review of the literature

Introduction and importance: Spontaneous coronary artery dissection (SCAD) is a rare but potentially fatal condition, often underdiagnosed despite its significance in acute coronary syndrome (ACS). The true prevalence remains uncertain due to diagnostic challenges. Identifying SCAD cases is crucial for reducing mortality and morbidity, especially considering the recurrence risk. The authors present two cases highlighting the importance of multimodality imaging in diagnosing and managing SCAD. Case presentation: Case 1: A 53-year-old man with a history of brain aneurysm presented with chest pain and shortness of breath. Despite negative EKGs and stress tests, coronary computed tomography angiography (CCTA) revealed non-obstructive dissection flaps. Medical management improved his condition. Case 2: A 55-year-old woman with no significant medical history experienced recurrent chest pain. Initial tests were negative, but CCTA revealed SCAD. Further screening uncovered undiagnosed fibromuscular dysplasia. Clinical discussion: SCAD poses diagnostic challenges, often mimicking other cardiac conditions. Traditional tests may yield negative results, necessitating advanced imaging techniques like CCTA. Recognizing SCAD’s association with connective tissue disorders (CTD) is vital for comprehensive patient care. The authors’ cases emphasize the importance of a systematic approach to diagnosing chest pain, including noninvasive modalities and considering underlying etiologies. Conclusion: SCAD diagnosis requires a high index of suspicion, especially when traditional cardiac tests are inconclusive. Beyond treatment, patients should undergo further evaluation for CTDs, particularly in those with minimal risk factors for atherosclerosis. Increased awareness and a multimodal diagnostic approach are crucial for timely intervention and improved outcomes in SCAD patients. Learning objectives: The authors aim to increase awareness regarding different clinical presentations of SCAD to decrease the risk of missed or late diagnosis. The authors’ case series also signifies the multimodal imaging approach’s role in evaluating chest pain. Upon diagnosis of SCAD, it is imperative to go beyond treatment and implement a reverse algorithmic strategy to discover any underlying causes and risk factors for SCAD predisposition.

Влияние рисков цифровизации на обеспечение экономической безопасности региона

The article discusses the impact of digitalization risks on ensuring the economic security of regions. The relevance of the research topic is due to changes in the trends in the deve-lopment of economic relations related to the digitalization of the economy. The article notes that the identification of risks and threats makes it possible to develop risk minimization procedures, draw up tactical and strategic plans focused on the prevention of risks and threats (“Mitigation”), the second stage - providing for measures and procedures if a risky situation has already occurred and it is necessary to eliminate the consequences or minimize losses from the occurrence of a risky event (“Contingency”). Special attention is paid to the classification of types and types of risks of digitalization. Based on the conducted research, the main types of risks are identified: the risks of using foggy and cloud technologies; the risks of fraud and violation of information confidentiality; the risks of technological lag, distributed by subgroups: software and hardware. It is noted that the improvement of digitalization procedures increases the convenience of calculations and the quality of life, allows you to optimize the processes in the activities of both legal entities and individuals, at the same time, has a significant impact on the economic security of legal entities and individuals, due to the high level of risk. In conclusion, examples of minimizing the risks of digitalization are given and tools and mechanisms for minimizing risks are proposed.

Multi-instance learning in the presence of positive and unlabeled bags

Multi-instance learning is a classic algorithm within the weakly supervised learning framework. Most previous approaches to multi-instance learning have typically assumed that every bag comes with its own label. However, in real-world applications, obtaining fully-labeled bags can be a challenging and resource-intensive task, primarily due to the substantial time and labor required for labeling each instance. Fortunately, collecting bags with only positive and unlabeled instances is a more feasible option. In this paper, we aim to learn an efficient binary classifier using positive and unlabeled bags. To address the absence of negative bags, we adopt a novel strategy that combines label noise learning and multi-instance kernels. Our approach involves a comprehensive analysis of empirical risk minimization in the presence of label noise, allowing us to decompose the loss function for negative bags with false negative labels into two distinct parts. Importantly, only the second part of this loss function is affected by the presence of noisy labels. To mitigate the influence of noisy labels on the negative bags, we propose the Multi-Instance Kernel-based Centroid Estimation (MIKCE) technique. MIKCE is a versatile method that can be employed with various types of data, including linear and nonlinear cases. Additionally, we provide an upper bound on the generalization error, ensuring the convergence of the MIKCE algorithm. Finally, we conduct numerical experiments on 31 public datasets to empirically validate the effectiveness of the MIKCE approach.

Time Series Methods to Assess the Impact of Regulatory Action: A Study of UK Primary Care and Hospital Data on the Use of Fluoroquinolones.

To illustrate the interest in using interrupted time series (ITS) methods, this study evaluated the impact of the UK MHRA's March 2019 Risk Minimisation Measures (RMM) on fluoroquinolone usage. Monthly and quarterly fluoroquinolone use incidence rates from 2012 to 2022 were analysed across hospital care (Barts Health NHS Trust), primary care (Clinical Practice Research Datalink (CPRD) Aurum and CPRD GOLD), and linked records from both settings (East Scotland). Rates were stratified by age (19-59 and ≥ 60 years old). Seasonality-adjusted segmented regression and ARIMA models were employed to model quarterly and monthly rates, respectively. Post-RMM, with segmented regression, both age groups in Barts Health experienced nearly complete reductions (> 99%); CPRD Aurum saw 20.19% (19-59) and 19.29% ( 60) reductions; no significant changes in CPRD GOLD; East Scotland had 45.43% (19-59) and 41.47% ( 60) decreases. Slope analysis indicated increases for East Scotland (19-59) and both CPRD Aurum groups, but a decrease for CPRD GOLD's 60; ARIMA detected significant step changes in CPRD GOLD not identified by segmented regression and noted a significant slope increase in Barts Health's 19-59 group. Both models showed no post-modelling autocorrelations across databases, yet Barts Health's residuals were non-normally distributed with non-constant variance. Both segmented regression and ARIMA confirmed the reduction of fluoroquinolones use after RMM across four different UK primary care and hospital databases. Model diagnostics showed good performance in eliminating residual autocorrelation for both methods. However, diagnostics for hospital databases with low incident use revealed the presence of heteroscedasticity and non-normal white noise using both methods.

Empirical risk minimization for big data driven prescriptive analytics: An exploration of two-stage stochastic programs with recourse

In the operations research literature, data driven analyses using big data are receiving more and more interest and attention. However, big data driven operational analyses are still limited in scope, with only unconstrained big data driven problems, e.g. the newsvendor problem, being comprehensively explored. If big data driven analyses are to become a core part of operations research and practice, one must be able to formulate and solve constrained big data driven models. We therefore propose a direct empirical risk minimization (DERM) method for formulating and solving a class of constrained big data driven operation research problems. In big data driven problems, relevant operational prescriptions are dependent on a set of observed features. In this paper, we assume linear feature relationships, which enable us to fundamentally base the DERM method on linear stochastic programming. The assumption of linear feature relationships is also seen in the literature on big data driven newsvendor models. We prove that if a big data driven solution exists, the DERM method will always, for the class of constrained problems we study, arrive at a feasible solution of the initial operational problem. Moreover, we exemplify the DERM method by formulating and solving two specific big data driven operational problems. In the numerical study of the two operational problems, we show, that under linear demand, the DERM method outperforms, with regard to cost, two benchmark methods and a big data driven method from literature.

Multi-objective optimal allocation of construction project risks, ant colony optimization algorithm

PurposeThe purpose of this paper is to introduce a new approach for finding the most appropriate risk allocation among construction contract parties. Although risk allocation is a strategic decision that can greatly affect the cost and time of the project, it is often made based on the personal judgments of employers. That is why owners usually find it a very time-consuming and expensive decision process, while most contractors feel that risk sharing is not done fairly. In this paper, a quantitative model for risk allocation is introduced to fulfill clients’ conflicting expectations in the risk allocation process.Design/methodology/approachBy defining conflicting expectation of owners in the form of three quantitative objectives (lowest cost, maximum reliability and minimum risk exposure), a multi-objective optimization algorithm was developed to select the most appropriate risk allocation. Using experts’ knowledge through fuzzy set theory, a multi-objective decision-making model is developed based on an ant colony optimization algorithm. The proposed model is able to find the optimum risk allocation at the lowest cost and highest reliability while protecting the client against risk exposure within multiple parties projects.FindingsThe proposed model has the ability to select the most appropriate risk allocation in multi-parties projects (such as public–private partnerships) and quantitatively measure the impact of each employer’s choice on project results in the form of cost and time. The results of implementing the proposed model in a case study project revealed that optimum risk allocation requires a balanced attitude, and the transfer of all risks to the other parties will not necessarily lead to the lowest cost. The client should bear more responsibilities in risk management to avoid extreme time delay and cost overrun.Research limitations/implicationsThe proposed model can be implemented in multi-parties projects (such as public–private partnership), while other methods introduced in previous studies can only be used for projects with two party (client and contractor).Practical implicationsBy implementing the proposed model in a real project in this article and comparing its results with previous works, it has been shown that the proposed model has a good performance. Using this model can help clients drastically reduce cost and time and ultimately successfully conclude risk allocation negotiations (which is the most difficult part of any contract negotiation).Originality/valueIn this paper, the risk allocation process is modeled in the form of a multi-objective decision problem. This method helps employers to measure their conflicting goals and choose the most appropriate risk allocation according to their objectives. Also, in this article, the conflicting expectations of the employer in the process of contract negotiations are introduced as three measurable goals, which gives the decision-maker the ability to balance his expectations and not miss an objective. In the final step, an optimization model is developed to select the best option, which can choose the most appropriate party to bear the risk in a short time and among an unlimited number of participants.

Health risk assessment of radiation dose level in oranges and mangoes fruits from farms in Benue State, Nigeria

The health risk and radiation dose level in Oranges and Mangoes due to ingestion from farm locations in Benue State was assessed. A total of fifty (50) samples were collected in five different farm locations in Benue State, the samples were washed with distilled water to remove dirt, a radiation meter was placed 10cm from the fruits and measurements were taken for 30 seconds, background radiation levels and radiation dose level from the fruits were measured and calculated. The results showed that the radiation dose level for Oranges ranged from 1.489 to 2.365 mSv/hr and 1.122 to 1.899 mSv/hr for mangoes and the Annual Equivalent Doses (AED) for Oranges and Mangoes consumption was estimated to be 0.107 and 0.027 mSv/yr, respectively. Both values exceeded the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA) recommended limit of 1.0 mSv/yr. The high radiation levels could be attributed to naturally occurring radioactive materials in the soil or water, contamination from nearby sources. The Excess Lifetime Cancer Risk (ELCR) was calculated, with values of 0.2677 for Oranges and 0.683 for Mangoes, which are lower than the safe limit specified by WHO. While there is minimal risk associated with radiation exposure from consuming these fruits, further monitoring and investigation are necessary to ensure food safety and security in the study area.

The Value of Pretherapeutic Basal Calcitonin Cut-Offs for the Therapeutic Strategy and Prediction of Long-Term Outcome of Patients with Medullary Thyroid Cancer—A 30-Year Single-Center Experience

Background: The clinical relevance of clearly defined pretherapeutic basal calcitonin (bCt) cut-offs for predicting lymph node metastases (LNMs) and long-term outcomes (LOs) has so far not been tested in a large cohort of patients with medullary thyroid cancer included in a Ct screening program during the initial diagnostic workup of thyroid nodules. Material and Methods: Female (f) patients with a bCt level of ≤23 pg/mL and male (m) patients with a level of ≤43 pg/mL were assigned to Group 1 (minimal oncologic risk), patients with a bCt between 24 and 84 pg/mL (f) and 44–99 pg/mL (m) to Group 2 (low oncologic risk), and those with a bCt of ≥85 pg/mL (f) and ≥100 pg/mL (m) to Group 3 (high oncologic risk). All patients underwent surgery applying a uniform surgical protocol. The median follow-up was 100 months. Results: The study included 306 patients. In 3/115 (2.6%) patients in Group 1 and in 3/50 (6.0%) in Group 2, LNM in the central but not lateral neck and no distant metastases (DMet) were documented. In both groups, the biochemical long-term cure rate was 95.7% and the disease-specific-survival (DSS) rate was 100% at 10, 15 and 20 years. Lateral LNM and DMet were diagnosed only in Group 3. The bCt levels of N0 and N1 patients showed broadly overlapping ranges, thus impeding the differentiation between those patients through bCt. Both the cure rate and DSS were significantly worse in Group 3. The overall biochemical long-term cure rate was 78.2%. Conclusions: Within a Ct screening program, grouping patients upon pretherapeutic bCt provides a simple risk classification system for indicating surgery, predicting LN involvement, and LOs.