Linkage of modules over Cohen-Macaulay rings

Inspired by the works in linkage theory of ideals, the concept of sliding depth of extension modules is defined to prove the Cohen-Macaulyness of linked module if the base ring is merely Cohen-Macaulay. Some relations between this new condition and other module-theory conditions such as G-dimension and sequentially Cohen-Macaulay are established. By the way several already known theorems in linkage theory are improved or recovered by new approaches.Comment: 12 Page

Comprehensive Flood Early Warning Systems: From Modelling to Policy Making Perspectives

Todays, early warning systems are widely applied in real-time flood forecasting operations as valuable non-structural tools for mitigating the impacts of floods [1]. Although many research works have perfectly could review recent advances in this era, current review papers tend to focus narrowly on specific perspectives, such as water quantity or quality [2]. Therefore, there is a pressing need for a more comprehensive and multi-disciplinary approach that not only explores various potential aspects of flood early warning system applications but also reveals the interconnections between these aspects [3]. This paper aims to bridge this gap by mapping out diverse applications and presenting significant trends, past initiatives, and future directions across a wide range of domains. By adopting such an approach, our goal is to provide a more holistic understanding of flood early warning systems and pave the way for further exploration in this critical field. This papers, as state-of-art, suggests that a comprehensive framework may include all these aspects to meet all desired task and also ensure that all aspect of sustainability, reliability, resiliency, and accuracy have been fulfilled: (1) using recent input data extracted from both well known resources such as ground station and satellite stations, and novel but local resources i.e. IoT-based remote sensing, drones, USV and even social media and qualitative data; (2) Advance modelling with focusing on hybrid deep learning and physics-informed neural networks for different type of flood i.e. fluvial, pluvial or surface run-off. Also, application of data mining for data screening still have required more attention; (3) Adding concept of water quality as target and outputs of EWS especially with focusing on emerging pollutants, biological pollutants and micro-plastics; (4) Interconnection of EWS with optimisation techniques, decision support systems, and multi criteria decision making processes; (5) Appropriate sensitivity/uncertainty analysis especially due to requirement for developing dynamic retrainable or self-trainable EWS; (6) Application of post modelling tools including virtual/augmented/mixed reality or digital twin to including stakeholder engagement.Peer reviewe

Enhancing community resilience in arid regions: A smart framework for flash flood risk assessment

This paper presents a novel framework for smart integrated risk management in arid regions. The framework combines flash flood modelling, statistical methods, artificial intelligence (AI), geographic evaluations, risk analysis, and decision-making modules to enhance community resilience. Flash flood is simulated by using Watershed Modelling System (WMS). Statistical methods are also used to trim outlier data from physical systems and climatic data. Furthermore, three AI methods, including Support Vector Machine (SVM), Artificial Neural Network (ANN), and Nearest Neighbours Classification (NNC), are used to predict and classify flash flood occurrences. Geographic Information System (GIS) is also utilised to assess potential risks in vulnerable regions, together with Failure Mode and Effects Analysis (FMEA) and Hazard and Operability Study (HAZOP) methods. The decision-making module employs the Classic Delphi technique to classify the appropriate solutions for flood risk control. The methodology is demonstrated by its application to the real case study of the Khosf region in Iran, which suffers from both drought and severe floods simultaneously, exacerbated by recent climate changes. The results show high Coefficient of determination (R2) scores for the three AI methods, with SVM at 0.88, ANN at 0.79, and NNC at 0.89. FMEA results indicate that over 50% of scenarios are at high flood risk, while HAZOP indicates 30% of scenarios with the same risk rate. Additionally, peak flows of over 24 m3/s are considered flood occurrences that can cause financial damage in all scenarios and risk techniques of the case study. Finally, our research findings indicate a practical decision support system that is compatible with sustainable development concepts and can enhance community resilience in arid regions

Cloning, expression, purification and CD analysis of recombinant human betatrophin

Betatrophin is a member of the angiopoietin-like (ANGPTL) family that has been implicated in both triglyceride and glucose metabolism. The physiological functions and molecular targets of this protein remain largely unknown; hence, a purified available protein would aid study of the exact role of betatrophin in lipid or glucose metabolism. In this study, we cloned the full-length cDNA of betatrophin from a human liver cDNA library. Betatrophin was expressed in the pET-21b-E. coli Bl21 (DE3) system and purified by immobilized metal-affinity chromatography and ion-exchange chromatography. Circular dichroism spectroscopy revealed α-helix as the major regular secondary structure in recombinant betatrophin. The production method is based on commonly available resources; therefore, it can be readily implemented

Cloning, expression, purification and CD analysis of recombinant human betatrophin

Betatrophin is a member of the angiopoietin-like (ANGPTL) family that has been implicated in both triglyceride and glucose metabolism. The physiological functions and molecular targets of this protein remain largely unknown; hence, a purified available protein would aid study of the exact role of betatrophin in lipid or glucose metabolism. In this study, we cloned the full-length cDNA of betatrophin from a human liver cDNA library. Betatrophin was expressed in the pET-21b-E. coli Bl21 (DE3) system and purified by immobilized metal-affinity chromatography and ion-exchange chromatography. Circular dichroism spectroscopy revealed α-helix as the major regular secondary structure in recombinant betatrophin. The production method is based on commonly available resources; therefore, it can be readily implemented

Pattern of contributing behaviors and their determinants among people living with HIV in Iran: A 30-year nationwide study

Introduction: A major shift in the routes of HIV transmission seams to be taking place in Iran. Our study aimed to investigate the 30-year trend of major HIV related behaviors in Iran. Methods: The national HIV/AIDS registry database (from September 1986 to July 2016 with data on 32,168 people newly diagnosed with HIV) was used to study the 30 years trend and demographic determinants of major HIV related behaviors. Results: The highest rate of drug injection (DI) among people living with HIV (PLHIV) was reported during 1996 to 1999 (p-for trend < 0.001) while the highest rate of sexual activity by minorities or hard to reach groups was during 2004 to 2011 (p-for trend < 0.001). Among males, drug injection was directly associated with being single (ORsingle/married = 1.34), being unemployed (ORunemployed/employed = 1.94) and having lower level of education (OR<highschool/≥highschool = 2.21). Regarding females, drug injection was associated with being housewife (ORhousewife/employed = 1.35) and lower level of education (OR<highschool/≥highschool = 1.85). In females, condomless sexual contact was more common among those younger (OR20−29/<20 = 6.15), and married (ORmarried/single = 7.76). However, among males those being single (ORmarried/single = 0.82), being more educated (OR≥highschool/<highschool = 1.24), and being unemployed (ORunemployed/employed = 1.53) reported more sexual activity by minoritised or hard to reach groups. Discussion: The pattern of major HIV related behaviors among Iranian males and females have been rapidly changing and people living with HIV (PLHIV) are being diagnosed at a younger age. Health education to younger individuals is an essential HIV controlling strategy among Iranian population. Implementation of surveys in hidden and hard-to-reach populations is also recommended. Copyright © 2023 Gheibi, Fararouei, Afrashteh, Akbari, Afsar Kazerooni and Shokoohi

Enhancing flood risk mitigation by advanced data-driven approach

Flood events in the Sefidrud River basin have historically caused significant damage to infrastructure, agriculture, and human settlements, highlighting the urgent need for improved flood prediction capabilities. Traditional hydrological models have shown limitations in capturing the complex, non-linear relationships inherent in flood dynamics. This study addresses these challenges by leveraging advanced machine learning techniques to develop more accurate and reliable flood estimation models for the region. The study applied Random Forest (RF), Bagging, SMOreg, Multilayer Perceptron (MLP), and Adaptive Neuro-Fuzzy Inference System (ANFIS) models using historical hydrological data spanning 50 years. The methods involved splitting the data into training (50–70 %) and validation sets, processed using WEKA 3.9 software. The evaluation revealed that the nonlinear ensemble RF model achieved the highest accuracy with a correlation of 0.868 and an root mean squared error (RMSE) of 0.104. Both RF and MLP significantly outperformed the linear SMOreg approach, demonstrating the suitability of modern machine learning techniques. Additionally, the ANFIS model achieved an exceptional R-squared accuracy of 0.99. The findings underscore the potential of data-driven models for accurate flood estimating, providing a valuable benchmark for algorithm selection in flood risk management

Electrospinning piezoelectric fibers for biocompatible devices

The field of nanotechnology has been gaining great success due to its potential in developing new generations of nanoscale materials with unprecedented properties and enhanced biological responses. This is particularly exciting using nanofibers, as their mechanical and topographic characteristics can approach those found in naturally occurring biological materials. Electrospinning is a key technique to manufacture ultrafine fibers and fiber meshes with multifunctional features, such as piezoelectricity, to be available on a smaller length scale, thus comparable to subcellular scale, which makes their use increasingly appealing for biomedical applications. These include biocompatible fiber-based devices as smart scaffolds, biosensors, energy harvesters, and nanogenerators for the human body. This paper provides a comprehensive review of current studies focused on the fabrication of ultrafine polymeric and ceramic piezoelectric fibers specifically designed for, or with the potential to be translated toward, biomedical applications. It provides an applicative and technical overview of the biocompatible piezoelectric fibers, with actual and potential applications, an understanding of the electrospinning process, and the properties of nanostructured fibrous materials, including the available modeling approaches. Ultimately, this review aims at enabling a future vision on the impact of these nanomaterials as stimuli-responsive devices in the human body

Structural and Activity Comparison of Native, Apo and Reconstituted Tyrosinase

Background: Mushroom Tyrosinase (MT) a potent candidate in clinical studies known as polyphenol oxidase, is a metaloenzyme from the oxidase superfamily widely distributed from lower to higher life forms. It plays a crucial role in sclerotization of exoskeleton in insects, also responsible for skin pigmentation in mammalians. Objective: In this study, after reconstitution of MT by some metal ions, the activity and structure of native, apo and reconstituted enzymes were investigated. Materials and Methods: Kinetic of reconstituted tyrosinase carried out in catecholase reaction by depletion of caffeic acid. Tertiary and secondary structure of apo, native and metal reconstituted tyrosinase obtained with fluorescence and circular dichroism techniques respectively. Reconstitution confirmed by Atomic Absorption Spectroscopy. Results: Kinetic assessment showed higher activity of MT reconstituted by Cu2+ and Ni2+ in comparison with native, Zn2+ and Co2+ reconstituted enzyme. The tertiary structure of enzyme by fluorescence technique indicated more stability of Ni2+ reconstituted MT and the apo form showed the lowest tertiary structure. Circular dichroism study showed that Ni2+ reconstituted MT form has more regular secondary structure and it caused higher stability of the enzyme. The molar ratio values from atomic absorption indicate that Ni2+ and Cu2+ have got the most binding to the apoenzyme. Conclusions: It has been shown that Ni2+, Zn2+ and Co2+ can replace Cu2+ in tyrosinase, indicating that the histidines at the active site of the tyrosinase family enzymes can be reconstituted with this metals, but, the most stabilization and well-structured enzyme was observed in the apotyrosinase reconstituted by Ni2+