Distinguishing Chromatic Number of Random Cayley graphs

The \textit{Distinguishing Chromatic Number} of a graph $G$, denoted $\chi_D(G)$, was first defined in \cite{collins} as the minimum number of colors needed to properly color $G$ such that no non-trivial automorphism $\phi$ of the graph $G$ fixes each color class of $G$. In this paper, we consider random Cayley graphs $\Gamma(A,S)$ defined over certain abelian groups $A$ and show that with probability at least $1-n^{-\Omega(\log n)}$ we have, $\chi_D(\Gamma)\le\chi(\Gamma) + 1$.Comment: 11 page

A study on exoenzyme activities of Candida albicans isolated from oral cavities of HIV-infected patients on HAART

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Plasma von Willebrand factor levels predict in-hospital survival in patients with acute-on-chronic liver failure

BACKGROUND AND AIMS: Circulating levels of von Willebrand factor (vWF) predict mortality in patients with cirrhosis. We hypothesized that systemic inflammation in acute-on-chronic liver failure (ACLF) will stimulate endothelium, increase vWF levels, and promote platelet microthrombi causing organ failure. METHODS: In this prospective study, we correlated plasma vWF levels with organ failure, liver disease severity, sepsis, and systemic inflammatory response syndrome (SIRS) and also analyzed if vWF levels predicted in-hospital composite poor outcome (i.e. death/discharged in terminal condition/liver transplantation) in consecutive ACLF patients. RESULTS: Twenty-one of the 50 ACLF patients studied had composite poor outcome. ACLF patients had markedly elevated vWF antigen and activity (sevenfold and fivefold median increase, respectively) on days 1 and 3. Median ratio of vWF to a disintegrin and metalloprotease with thrombospondin type 1 motif, member 13 (ADAMTS13) activity on day 1 was significantly higher in ACLF patients (11.2) compared to 20 compensated cirrhosis patients (3.3) and healthy volunteers (0.9). On day 1, area under ROC curve (AUROC) to predict composite poor outcome of hospital stay for ACLF patients for vWF antigen, vWF activity, and model for end-stage liver disease (MELD) score were 0.63, 0.68, and 0.74, respectively. vWF activity correlated better with liver disease severity (MELD score, ACLF grade) and organ failure (Sequential Organ Failure Assessment [SOFA] score) than vWF antigen; in contrast, neither vWF antigen nor activity correlated with platelet count, sepsis, or SIRS. CONCLUSIONS: vWF levels are markedly elevated, correlate with organ failure, and predict in-hospital survival in ACLF patients. This data provides a mechanistic basis for postulating that vWF-reducing treatments such as plasma exchange may benefit ACLF patients

The role of Cornichon (Cni) in axis formation in Drosophila

Summary During oogenesis, in Drosophila melanogaster, the exchange of signals between the oocyte and the surrounding follicle cells govern both the polarization of the maturing egg and the subsequent establishment of the future embryonic body axes. Gurken (Grk), a TGF-α-like molecule signaling twice from the oocyte to the overlying follicle cells brings about the polarisation of both axes, the anterior-posterior (AP) and the dorsal-ventral (DV). The signal is perceived by the Drosophila EGF receptor (DER) present in abutting follicle cells. Cornichon (Cni) is a small hydrophobic protein which is absolutely required for Grk signaling. Earlier studies, in the lab, has shown a protein-protein interaction between the ER-luminal domain of Cni and the juxtamembrane domain (JMD) domain of Grk. In this study, it has been shown that the subcellular localisation of Cni is in line with an ER to Golgi cycling function. By inducing Grk transit through the bulk flow pathway of cellular exocytosis it could be shown that the requirement for Cni in enrichment of Grk vesicles can be overcome. Grk secreted via the bulk flow pathway in absence of Cni is active and signals to the DER. This demonstrates that Cni function is restricted to the transport of Grk from the ER to the Golgi and is not required for modification and/or proteolytic activation of Grk. This mode of ligand trafficking is a new component of the EGF ligand regulatory system. cni is not only required in the oocyte, it has also a somatic functions as indicated by head and wing phenotypes and decreased viability which result from amorphic cni mutations. The somatic, but not the ovarian functions of cni can be rescued by cornichon related (cnir). An earlier study in the lab revealed that a chromosomal deficiency removing regions including cnir is synthetically lethal with cni. A genetic screen was conducted to identify a putative loss of function allele of cnir, from an existing collection of EMS allele in this region. The molecular characterisation of the allele is not yet completed. In addition, an enhancer/suppressor screen in a sensitized genetic background to identify new components or new unidentified roles for known components, in the initiation of the DV axis was conducted. As the sensitized background, a cni hypomorphic allele combination which leads to strongly ventralized eggs with a weak defect in posterior follicle cell specification was used. Deficiencies on the third chromosome were assayed for suppression or enhancement of the cni egg phenotype or for synthetic lethality, upon gene dosage reduction.Eight candidates regions of the third chromosome consisting of one suppressor, four enhancers and three synthetic lethal were identified. The suppression was narrowed down to a single gene namely, pipe. pipe is a gene which is activated directly by the Grk gradient and its activity defines the ventral side of the egg and embryo. Of the other interactors, four of them have been narrowed down to regions containing a few genes

Particle Swarm Optimization and Ant Colony Optimization For Bi-Objective Optimization For A Single Batch Processing Machine

This research studies the scheduling of jobs with unequal ready times, unequal processing times, and unequal sizes on a single batch processing machine, with the objectives of minimizing makespan and maximum tardiness. For the batch process, the jobs are required to be grouped into batches and further these batches are scheduled on the machine to minimize the objectives, without violating the machine capacity. The problem under study can be denoted as 1|p-batch, sj, rj| Cmax,Tmax in the standard three-field notation. A thorough review of literature pertinent to the field of research has been conducted and two new approaches have been proposed in this research.Ghrayeb (2020) has shown this problem to be NP-hard and proposed a mathematical formulation using the weighted sum approach which was solved using IBM ILOG CPLEX. Additionally, Ghrayeb (2020) also proposed a simulated annealing (SA) and a greedy randomized adaptive search procedure (GRASP) to solve the problem for a set of 225 instances generated by varying values of job sizes, processing times, ready times, and due dates. Since the problem is NP-hard, the computational time to solve the problem under study may increase exponentially, which is not desired in real life. Therefore, a Particle Swarm Optimization (PSO) and an Ant Colony Optimization (ACO) algorithm are proposed for the problem. The proposed algorithms are analyzed in terms of the quality of the solution and run time required to solve the same dataset used in Ghrayeb (2020). The solutions from PSO and ACO are compared to the results from Simulated Annealing (SA), Greedy Randomized Adaptive Search Procedure (GRASP), and CPLEX found in Ghrayeb (2020) as well as Goal Programming (G), Goal Programming with Symmetry Breaking (G+), Goal Programming with Modified Symmetry Breaking (GM+), and Column Generation (CG) approaches found in Srinivasan Sampathi (2021). Additional metrics such as Mean Ideal Distance (MID), Diversification Matrix (DM), the Spread of Non-Dominance Solutions (SNS), and the number of non-dominated solutions are calculated for each of the proposed algorithms for a better evaluation of their performance. Based on the results, ACO seems to be a better approach for larger job instances for the proposed problem. Both ACO and PSO outperform CPLEX for 150-job instances. Despite ACO underperforming for smaller job instances, ACO offers significant time savings for all instances when compared to CPLEX and also provides higher-quality solutions. The findings of this research can be used by schedulers in the industry to effectively group the jobs into batches and schedule them on batch processing machines, easing the pain of scheduling a large number of jobs

Interdisciplinary studies on stingless bees as alternate managed pollinators

The aim of the work described in this thesis is to improve the preparedness of the horticulture industry for the possible incursion of varroa mite and decline of managed honey bees by developing stingless bees as alternate managed pollinators. In this thesis, we conduct various surveys and experiments that contribute to improving pollination provisioning by native stingless bees. With research predicting ongoing changes in the global environment and resultant fluctuations in pollinator communities , it has become essential to focus on studying alternate and native pollinators. One such pollinator group is the stingless bees, which have a pan-tropical distribution, with a few species in the subtropics and temperate regions. The chapters of my thesis address questions that are yet to be solved regarding adoption of alternate managed pollination, such as the influence of farm management on crop pollination, and documenting the current knowledge among growers and beekeepers regarding managed pollination in India and Australia. In Chapter 2 I study and establish the current nature and status of beekeeping practices in India. Additionally, I study the current knowledge of growers regarding pollinators and pollination service. Overall it was established that growers know very little about pollination and beekeepers predominantly keep the honeybee, Apis mellifera, for honey production rather than for pollination. I then survey the Australian stingless bee industry (Chapter 3), documenting its growth in the past decade and comparing observed patterns to those in two previous decadal surveys. The decadal survey concludes that the stingless bee industry has a higher growth rate than the honey bee industry in Australia. An important step in developing stingless bees as alternate managed pollinators is to look at the effect of farm management on various insect visitors such as pollinators, beneficials and pests. In Chapter 4 I study the effects of farm management practices on insect visitors to conclude that low-spray management practices are an effective method to combat pests while maintaining unmanaged pollinators and beneficials on the orchard. Lastly, I compare various pollination methods – stingless bee pollination, hand pollination and no pollination within a protected cropping system for strawberry production and compare their cost-effectiveness (Chapter 5). The study concludes that strawberry growers will benefit from investing in bee pollination to improve their economic efficiency. Ultimately, these new insights contribute towards our understanding in developing stingless bees as alternated managed pollinators

Investigating the Key Factors Influencing Customer Satisfaction Case of Start-up Restaurant in Finland

The restaurant sector in Finland has seen growth, However, start-up restaurants face hurdles, including intense competition, elevated operating costs, and limited brand visibility. Many fail within first three years due to financial instability and inadequate customer satisfaction. This research “investigates key factors influencing customer satisfaction in start-up restaurants”, using Company X, a fried chicken restaurant in Tampere, as a case study. The study highlights four independent variables: marketing strategies, menu innovation, location, and digitalization, with customer satisfaction being the dependent variable. A quantitative approach was taken, with the help of a survey collecting data from 50 participants, including dine-in customers. It uses a Likert scale to assess variables, and data analysis involved descriptive statistics, correlation, and regression techniques The results showed menu innovation strongly influenced customer satisfaction, highlighting the need for unique and attractive menu options. Marketing strategies had a notable positive effect, especially via digital platforms and targeted advertising. Location indicated a moderate link with satisfaction, stressing accessibility and convenience as key factors. Digitalization, through online ordering systems and social media interaction, proved critical for improving customer experience. Regression analysis validated the combined impact of these variables. The study concludes by providing actionable recommendations to optimize marketing efforts, innovate menu offerings, leverage digital tools, and improve customer experience. These findings contribute to understanding the unique challenges faced by start-up restaurants and offer practical strategies to enhance customer satisfaction, ensuring long-term growth and sustainability in Finland’s competitive restaurant industry. Keywords: Customer Satisfaction, Start-up Restaurants, Marketing Strategies, Menu Innovation, Digitalization