Second-Order Algebraic Theories

Fiore and Hur recently introduced a conservative extension of universal algebra and equational logic from first to second order. Second-order universal algebra and second-order equational logic respectively provide a model theory and a formal deductive system for languages with variable binding and parameterised metavariables. This work completes the foundations of the subject from the viewpoint of categorical algebra. Specifically, the paper introduces the notion of second-order algebraic theory and develops its basic theory. Two categorical equivalences are established: at the syntactic level, that of second-order equational presentations and second-order algebraic theories; at the semantic level, that of second-order algebras and second-order functorial models. Our development includes a mathematical definition of syntactic translation between second-order equational presentations. This gives the first formalisation of notions such as encodings and transforms in the context of languages with variable binding

Risk Without Return

Risk-only investment strategies have been growing in popularity as traditional in- vestment strategies have fallen short of return targets over the last decade. However, risk-based investors should be aware of four things. First, theoretical considerations and empirical studies show that apparently dictinct risk-based investment strategies are manifestations of a single effect. Second, turnover and associated transaction costs can be a substantial drag on return. Third, capital diversification benefits may be reduced. Fourth, there is an apparent connection between performance and risk diversification. To analyze risk diversification benefits in a consistent way, we introduce the Risk Diversification Index (RDI) which measures risk concentrations and complements the Herfindahl-Herschman Index (HHI) for capital concentrations

Diversification Preferences in the Theory of Choice

Diversification represents the idea of choosing variety over uniformity. Within the theory of choice, desirability of diversification is axiomatized as preference for a convex combination of choices that are equivalently ranked. This corresponds to the notion of risk aversion when one assumes the von-Neumann-Morgenstern expected utility model, but the equivalence fails to hold in other models. This paper studies axiomatizations of the concept of diversification and their relationship to the related notions of risk aversion and convex preferences within different choice theoretic models. Implications of these notions on portfolio choice are discussed. We cover model-independent diversification preferences, preferences within models of choice under risk, including expected utility theory and the more general rank-dependent expected utility theory, as well as models of choice under uncertainty axiomatized via Choquet expected utility theory. Remarks on interpretations of diversification preferences within models of behavioral choice are given in the conclusion

Second-Order Algebraic Theories

Second-order universal algebra and second-order equational logic respectively provide a model theory and a formal deductive system for languages with variable binding and parameterised metavariables. This dissertation completes the algebraic foundations of second-order languages from the viewpoint of categorical algebra. In particular, the dissertation introduces the notion of second-order algebraic theory. A main role in the definition is played by the second-order theory of equality M, representing the most elementary operators and equations present in every second-order language. We show that M can be described abstractly via the universal property of being the free cartesian category on an exponentiable object. Thereby, in the tradition of categorical algebra, a second-order algebraic theory consists of a cartesian category M and a strict cartesian identity-on-objects functor M: M →M that preserves the universal exponentiable object of M. At the syntactic level, we establish the correctness of our definition by showing a categorical equivalence between second-order equational presentations and second-order algebraic theories. This equivalence, referred to as the Second-Order Syntactic Categorical Type Theory Correspondence, involves distilling a notion of syntactic translation between second-order equational presentations that corresponds to the canonical notion of morphism between second-order algebraic theories. Syntactic translations provide a mathematical formalisation of notions such as encodings and transforms for second-order languages. On top of the aforementioned syntactic correspondence, we furthermore establish the Second-Order Semantic Categorical Type Theory Correspondence. This involves generalising Lawvere’s notion of functorial model of algebraic theories to the second-order setting. By this semantic correspondence, second-order functorial semantics is shown to correspond to the model theory of second-order universal algebra. We finally show that the core of the theory surrounding Lawvere theories generalises to the second order as well. Instances of this development are the existence of algebraic functors and monad morphisms in the second-order universe. Moreover, we define a notion of translation homomorphism that allows us to establish a 2-categorical type theory correspondence

Using CA-Markov Model to Predict Land Use/Land Cover Changes in Bayer and al-Bassit region, Latakia, Syria

Recently, land use change models have become important tools to support the analysis of land use dynamics. This research was aimed at the evaluating and predicting the land use/land cover change dynamics in Bayer and al-Bassit region of northwestern Latakia, Syria. In this paper, we used Cellular Automata and Markov Chain models to predict the LULC changes that are likely to occur by 2030 in Bayer and al-Bassit region. Three Landsat images acquired in the years of 1992, 2005, and 2018 were classified using Maximum Likelihood Classification algorithm and used as the input data for CA-Markov models. Kappa index was used to validate the model, and the overall accuracy recorded 79.34%. Based on a transition area matrix and transition rules a LULC map for the year 2030 were predicted. Compared to the LULC status of the reference year 2018, a significant reduction is likely to occur in 2030 in the forest area. This reduction might be in favor of the growth of agricultural land and urban area. The result shows CA-Markov model ability to predict future LULC changes in Bayer and al-Bassit region, and its importance for planners and land use managers

Effect of Designing and Implementing Nursing Guidelines on Nurses' Performance in Caring Women with Ectopic Pregnancy

Context: Ectopic pregnancy is a condition presenting a significant health problem for women of the childbearing period. Ectopic pregnancy remains one of the primary causes of maternal mortality. Aim: The study aimed to evaluate the effect of nursing guidelines for improving maternity nurses' performance regarding ectopic pregnancy. Methods: A quasi-experimental design was used to achieve the aim of the study. The study was conducted at Obstetrics and Gynecology Department at Benha University Hospital. A convenient sample of all nurses (90 nurses) working in Obstetrics and Gynecology departments at Benha university hospital. Tools of data collection included a structured self-administered questionnaire to assess nurses' knowledge regarding ectopic pregnancy, an observational checklist to evaluate nursing practice regarding ectopic pregnancy before and after implementing the nursing guidelines. Results: 78.9% of the studied nurses had a total incorrect knowledge preprogram, which improved to 88.9% of them and had correct knowledge post-program. The study also shows that 47.2% of the studied nurses had unsatisfactory total practice score preprogram, which improved to 54.4% of the studied nurses who had high satisfactory total practice post-program. There was a highly statistically significant difference before and after nursing guidelines of the studied nurses’ knowledge and practice regarding ectopic pregnancy (P ≤ 0.001). Conclusion: The study concluded that nursing guidelines positively affect the nurses' performance in terms of their knowledge and practice regarding ectopic pregnancy. The study recommended that simple guidelines regarding ectopic pregnancy nursing care should be distributed to nurses in the emergency obstetrics department to standardize and optimize nursing care provided to women with ectopic pregnancies. Continuous refreshment courses and follows up programs for nurses regarding ectopic pregnancy

Evaluation of differential white blood cell count and cheek pouch epithelium in 7,12-dimethylbenza[a]anthracene hamster carcinogenesis model, managed with three phytochemicals

Objectives: Nigella sativa (NS), thymoquinone (TQ), and epigallocatechin-3-gallate (EGCG) are phytochemicals that might have antioxidant protective potentials on the hamster cheek pouch epithelium (HCPE). We aimed at evaluating and comparing the potential therapeutic outcomes of these 3 phytochemicals by analysis of peripheral white blood cells (WBCs) counts. Materials and Methods: NS whole oil, TQ and EGCG were administered before, with or after 7,12-dimethylbenza[a]anthracene (DMBA) painting the hamster left cheek pouch. Before sacrificing each animal, 2 ml of blood was withdrawn into a fine heparin-containing tube to estimate the total WBCs, lymphocytes, MID cells, and granulocytes counts by an automatic count system. All cheek pouches were surgically excised and examined with light microscope. Results: Severe epithelial dysplasia was evident after 6 weeks of DMBA administration, and when NS was given for 2 weeks followed by DMBA for 6 weeks. When NS or EGCG were given for 2 weeks then continued with DMBA for 6 weeks, mild dysplasia was seen. When DMBA was given for 6 weeks followed by NS or TQ for 6 weeks, mild dysplasia was noted. Administration of DMBA for 6 weeks resulted in significant reduction in total WBCs and lymphocytes counts compared to healthy controls. Administration of NS or TQ for 2 weeks resulted in significant elevation in lymphocytes count compared to healthy controls. Significant elevation in total WBCS and lymphocytes counts was noted when EGCG was given for 2 weeks and continued with DMBA for other 6 weeks. Similar results were noted when DMBA was given for 6 weeks followed by TQ for 6 weeks when compared to NS, DMBA or healthy controls. Discussion: The three phytochemicals showed different levels of protection against DMBA carcinogenic activity, more specifically, TQ and NS had higher therapeutic potential and might be used for treatment and/or preventive management of oral cancer in the future. Conclusion: However, further investigations are required to address the mechanism of action and feasibility of clinical application of each phytochemical

Alternative Aggression among University Students

"هدف البحث الحالي التعرف إلى:        العدوان البديل لدى طلبة الجامعة. الفروق ذات الدلالة الإحصائية في العدوان البديل على وفق "الجنس- التخصص" لدى طلبة الجامعة.        ولتحقيق أهداف البحث اقتضى توفر أداة لقياس العدوان البديل لدى طلبة الجامعة, لذا  قام الباحثان ببناء المقياس وفق نظرية دولارد وآخرون, إذ تكوّن المقياس من (40) فقرة، وتألفت الاستجابة على فقرات المقياس وهي خمسة بدائل: (دائماً، غالباً، أحياناً، نادراً، ابداً) وبعد التحقق من الخصائص السيكومترية لمقياس البحث وفقراتهما، طُبق على عينة البحث الأساسية البالغة (377) طالبا وطالبة من طلبة الجامعة كان اختيارهم بالأسلوب الطبقي العشوائي المتناسب، وبعد تحليل البيانات إحصائياً باستعمال الحقيبة الإحصائية للعلوم الاجتماعية (SPSS)، أفرزت النتائج ما يلي:       لدى طلبة الجامعة (عدوان بديل). لا توجد فروق ذات دلالة إحصائية, لدى طلبة الجامعة وفق متغير الجنس, لا توجد فروق ذات دلالة إحصائية تبعاً لمتغير التخصص (إنساني, علمي). لا توجد فروق ذات دلالة إحصائية. بالتفاعل بين (الجنس* التخصص)".         The aim of the current research is to identify: Alternative aggression among university students. 2.Statistically significant differences in alternative aggression according to "sex - specialization" among university students.         In order to achieve the objectives of the research, it was necessary to provide a tool for measuring alternative aggression among university students, so the researcher built the scale according to the theory of Dollard and others. rarely, never) and after verifying the psychometric properties of the research scale and their paragraphs, they were applied to the main research sample of (377) male and female students from the university students who were chosen in a proportional random stratified manner, and after analyzing the data statistically using the statistical bag for social sciences (SPSS), the results were produced the following:        University students have (alternative aggression). There are no statistically significant differences among university students according to the gender variable. There are no statistically significant differences according to the specialization variable (humanitarian, scientific). There are no statistically significant differences. By interaction between (gender * specialization)

Short-Term and Long-Term COVID-19 Pandemic Forecasting Revisited with the Emergence of OMICRON Variant in Jordan

Three simple approaches to forecast the COVID-19 epidemic in Jordan were previously proposed by Hussein, et al.: a short-term forecast (STF) based on a linear forecast model with a learning database on the reported cases in the previous 5–40 days, a long-term forecast (LTF) based on a mathematical formula that describes the COVID-19 pandemic situation, and a hybrid forecast (HF), which merges the STF and the LTF models. With the emergence of the OMICRON variant, the LTF failed to forecast the pandemic due to vital reasons related to the infection rate and the speed of the OMICRON variant, which is faster than the previous variants. However, the STF remained suitable for the sudden changes in epi curves because these simple models learn for the previous data of reported cases. In this study, we revisited these models by introducing a simple modification for the LTF and the HF model in order to better forecast the COVID-19 pandemic by considering the OMICRON variant. As another approach, we also tested a time-delay neural network (TDNN) to model the dataset. Interestingly, the new modification was to reuse the same function previously used in the LTF model after changing some parameters related to shift and time-lag. Surprisingly, the mathematical function type was still valid, suggesting this is the best one to be used for such pandemic situations of the same virus family. The TDNN was data-driven, and it was robust and successful in capturing the sudden change in +qPCR cases before and after of emergence of the OMICRON variant