A static benchmarking for grid scheduling problems

Analysis of algorithms for Grid computing systems before deployment in real Grid infrastructures is an important issue in Grid computing domain. Due to the complexity of real Grid systems, assessing performance analysis of optimization algorithms such as scheduling algorithms, is in general difficult, costly and time consuming. Benchmarking and simulation are two most used alternatives for analyzing optimization algorithms in Grid systems before deployment. In this paper we present a static benchmarking for scheduling problems in Grid systems. The benchmarking has been generated using the HyperSim-G Grid simulator and captures several types of Grid systems based on combinations of different machine and task types. Instances have six different sizes ranging from tiny (32 machines/512 tasks) to extra large size (1024 machines/16384 tasks) and are grouped according to machine and task types. The benchmark suite, consisting of about 720 instances, is offered through a web pagePeer ReviewedPostprint (published version

Copper and Zinc Metal–Organic Frameworks with Bipyrazole Linkers Display Strong Antibacterial Activity against Both Gram+ and Gram− Bacterial Strains

: Here, we report a new synthetic protocol based on microwave-assisted synthesis (MAS) for the preparation of higher yields of zinc and copper in MOFs based on different bis(pyrazolyl)-tagged ligands ([M(BPZ)]n where M = Zn(II), Cu(II), H2BPZ = 4,4'-bipyrazole, [M(BPZ-NH2)]n where M = Zn(II), Cu(II); H2BPZ-NH2 = 3-amino-4,4'-bipyrazole, and [Mx(Me4BPZPh)] where M = Zn(II), x = 1; Cu(II), x = 2; H2Me4BPZPh = bis-4'-(3',5'-dimethyl)-pyrazolylbenzene) and, for the first time, a detailed study of their antibacterial activity, tested against Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria, as representative agents of infections. The results show that all MOFs exert a broad-spectrum activity and strong efficiency in bacterial growth inhibition, with a mechanism of action based on the surface contact of MOF particles with bacterial cells through the so-called "chelation effect" and reactive oxygen species (ROS) generation, without a significant release of Zn(II) and Cu(II) ions. In addition, morphological changes were elucidated by using a scanning electron microscope (SEM) and bacterial cell damage was further confirmed by a confocal laser scanning microscopy (CLSM) test

Metformin and Covid-19: a systematic review of systematic reviews with meta-analysis

: the COVID-19 infection, caused by severe Coronavirus 2 syndrome (Sars-Cov-2), immediately appeared to be the most tragic global pandemic event of the twentieth century. Right from the start of the pandemic, diabetic patients treated with metformin experienced a reduction in mortality and complications from COVID-19 compared to those with different treatments or no treatment. Objective The main objective of the study was to observe the effects of metformin in hospitalized subjects infected with COVID-19. Specifically, the outcomes of hospitalization in Intensive Care Units or death were examined. Materials and Methods A specific research PICOS was developed and the Pubmed, Embase and Scopus databases were consulted down to April 30, 2022. To estimate the extent of the metformin effect and risk of severity in SARS-CoV-2 infection, the Odd Ratio (OR) with 95% Confidence Interval (CI) published by the authors of the selected systematic reviews was used. Results from five systematic reviews 36 studies were selected. The final meta-analysis showed that thanks to treatment with metformin, DM2 patients affected by COVID-19 had protection against risk of disease severity, complications (ES 0.80; 95% CI) and mortality (ES 0.69; 95% CI). Conclusions More in-depth studies on the use of metformin, compared to other molecules, may be required to understand the real protective potential of the drug against negative outcomes caused by COVID-19 infection in DM2 patients

Meta-heuristically seeded genetic algorithm for independent job scheduling in grid computing

Grid computing is an infrastructure which connects geographically distributed computers owned by various organizations allowing their resources, such as computational power and storage capabilities, to be shared, selected, and aggregated. Job scheduling problem is one of the most difficult tasks in grid computing systems. To solve this problem efficiently, new methods are required. In this paper, a seeded genetic algorithm is proposed which uses a meta-heuristic algorithm to generate its initial population. To evaluate the performance of the proposed method in terms of minimizing the makespan, the Expected Time to Compute (ETC) simulation model is used to carry out a number of experiments. The results show that the proposed algorithm performs better than other selected techniques

New Zinc-Based Active Chitosan Films: Physicochemical Characterization, Antioxidant, and Antimicrobial Properties

The improvement of the antioxidant and antimicrobial activities of chitosan (CS) films can be realized by incorporating transition metal complexes as active components. In this context, bioactive films were prepared by embedding a newly synthesized acylpyrazolonate Zn(II) complex, [Zn(QPhtBu)2(MeOH)2], into the eco-friendly biopolymer CS matrix. Homogeneous, amorphous, flexible, and transparent CS@Znn films were obtained through the solvent casting method in dilute acidic solution, using different weight ratios of the Zn(II) complex to CS and characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR), Raman, and scanning electron microscopy (SEM) techniques. The X-ray single-crystal analysis of [Zn(QPhtBu)2(MeOH)2] and the evaluation of its intermolecular interactions with a protonated glucosamine fragment through hydrogen bond propensity (HBP) calculations are reported. The effects of the different contents of the [Zn(QPhtBu)2(MeOH)2] complex on the CS biological proprieties have been evaluated, proving that the new CS@Znn films show an improved antioxidant activity, tested according to the DPPH method, with respect to pure CS, related to the concentration of the incorporated Zn(II) complex. Finally, the CS@Znn films were tried out as antimicrobial agents, showing an increase in antimicrobial activity against Gram-positive bacteria (Staphylococcus aureus) with respect to pure CS, when detected by the agar disk-diffusion method

A budget feasible peer graded mechanism for iot-based crowdsourcing

We develop and extend a line of recent works on the design of mechanisms for heterogeneous tasks assignment problem in ’crowdsourcing’. The budgeted market we consider consists of multiple task requesters and multiple IoT devices as task executers. In this, each task requester is endowed with a single distinct task along with the publicly known budget. Also, each IoT device has valuations as the cost for executing the tasks and quality, which are private. Given such scenario, the objective is to select a subset of IoT devices for each task, such that the total payment made is within the allotted quota of the budget while attaining a threshold quality. For the purpose of determining the unknown quality of the IoT devices we have utilized the concept of peer grading. In this paper, we have carefully crafted a truthful budget feasible mechanism for the problem under investigation that also allows us to have the true information about the quality of the IoT devices. Further, we have extended the set-up considering the case where the tasks are divisible in nature and the IoT devices are working collaboratively, instead of, a single entity for executing each task. We have designed the budget feasible mechanisms for the extended versions. The simulations are performed in order to measure the efficacy of our proposed mechanismPeer ReviewedPostprint (author's final draft

Underground Wireless Channel Bandwidth and Capacity

The UG channel bandwidth and capacity are vital parameters in wireless underground communication system design. In this chapter, a comprehensive analysis of the wireless underground channel capacity is presented. The impact of soil on return loss, bandwidth, and path loss is discussed. The results of underground multi-carrier modulation capacity are also outlined. Moreover, the single user capacity and multi-carrier capacity are also introduced with an in-depth treatment of soil texture, soil moisture, and distance effects on channel capacity. Finally, the chapter is concluded with a discussion of challenges and open research issues

Methods of negotiation in online collaborative mathematics problem-solving

The Virtual Math Teams (VMT) project is an NSF-funded research program through which researchers at the College of Information Science and Technology (IST) and the Math Forum investigate the innovative use of online collaborative environments to support effective K-12 mathematics learning. Negotiation is an indispensable element in collaboration, especially in the resolution of situations whose complexity is such that understanding them is enhanced by multiple perspectives made possible through collaboration. Some mathematics problems which are described as ‘ill-structured’ because they admit of several possible interpretations and multiple solutions, are candidates for collaborative problem-solving. Negotiation is necessary to make this collaborative approach possible, inasmuch as sense- and meaning-making associated with this particular approach to problem-solving has for its distinctive characteristic, the dynamics of a group rather than the jig-saw style of cooperating individuals. A research methodology based on conversation analysis is used to identify how negotiation is conducted in online mathematics problem-solving by locating its methods as negotiation is initiated, processed and concluded. Initial findings show: - how changes in the tempo of turn-taking indicate shifts in the conduct of problem-solving, - how repetition and ‘forced conclusions’ are used to negotiate a choice among several problems at hand, - how intervals and transitions are used by participants to indicate preferred responses and responders, - how referencing tools impact negotiation. Findings from this research can assist in the design of CSCL environments, especially in the transformation of generic communication applications to collaborative technology

Virtual math teams (VMT): Continuity and sustainability of collaborative knowledge building

How can we support online groups to better sustain their collaborative learning activity over time? In this poster, we present a qualitative case study of group creativity online in the domain of mathematics. We define collaborative learning work broadly, ranging from the micro-level co-construction of novel resources for collective problem solving to the innovative reuse and expansion of ideas across multiple virtual teams. Based on our analysis of the collaborative interactions of five virtual math teams we characterize the relationship between "synchronic" aspects of collaborative knowledge building (i.e. single episode interactions) and their "diachronic" evolution across time and across collectivities. Our analysis indicates that the synergy between these two types of interactions and the resulting creative engagement of the teams relies on three fundamental processes: (1) referencing and the “configuration of indexicals”, (2) collective remembering, and (3) bridging across discontinuities. In addition we also reflect on the aspects of the online environment used by these virtual teams which promote, support or hinder diachronic and synchronic interactions leading to successful knowledge building