Chronology for Mississippian and Oneota Occupations at Aztalan and the Lake Koshkonong Locality

The Middle Mississippian component at Aztalan was a mixed, Late Woodland / Mississippian occupation sited within a heavily fortified habitation and mound center that is located on a tributary of the Rock River in Wisconsin. It represents the northernmost large Cahokian-related village recorded. The Oneota Lake Koshkonong Locality of the Rock River drainage is located approximately 20 km south of Aztalan, and it consists of a 25 km2 area along the northwest shore with a small cluster of habitation settlements. Sixty-eight radiocarbon measurements have been obtained from Aztalan, and 52 from Oneota settlements in the Lake Koshkonong Locality. We discuss how to best interpret this dataset, and we use Bayesian chronological modeling to analyze these dates. The results suggest that (1) Aztalan's Late Woodland (Kekoskee phase) occupation began in the AD 900s or early AD 1000s, (2) Aztalan's Mississippian occupation ceased in the AD 1200s, (3) Oneota occupations at Lake Koshkonong began after AD 1050 and were established by the AD 1200s, and (4) Oneota occupations at Lake Koshkonong continued after Aztalan's Mississippian abandonment until at least the late AD 1300s. Additionally, the results demonstrate that Aztalan was fortified with a palisade with bastions for much of the Mississippian occupation, suggesting a contested presence in a multiethnic landscape.

Croatian Pupils' Perspectives on Remote Teaching and Learning during the COVID-19 Pandemic

On March 16th 2020, the Croatian government mandated a nationwide closure of schools and introduced remote teaching and learning in response to the COVID-19 pandemic. The present study explores the perspectives of pupils in the 7th grade of elementary education regarding this period of remote teaching and learning. The study aims to examine the level and determinants of pupils' satisfaction with newly implemented practices and to explore their perception of remote teaching and learning in comparison to classroom practices. An online survey was conducted with 920 pupils from 23 elementary schools in Zagreb between May 25th and June 6th 2020. The results indicate average satisfaction levels and a weak ability of the model to predict pupils' satisfaction based on a set of individual pupil characteristics. Pupils' interest in using digital devices and fathers' educational status were the only significant predictors of satisfaction. On average, pupils perceived remote teaching and learning as unfavourable in terms of quality, task load and effort in comparison to classroom practices. There was, however, a small cluster of pupils (15%) who associated remote teaching and learning with higher-quality practices.

A Controllable RSU and Vampire Moth to Support the Cluster Stability in VANET

VANET has a dynamic topology that affects cluster formation stability. It influences vehicle’s network quality though supporting this stability requires a fast and small cluster formation process. It is necessary because of the rapidly changing condition of the vehicle's position. Moreover, small cluster groups make network quality more evenly distributed among its members. They are essential components in the formation of good clusters in VANET. In the previous research, the algorithm used for this process is based on moth flame optimization. This study proposes modifications in this algorithm to speed up the convergence process, facilitated by a model of turning angles in the moth. Furthermore, the flame at the destination moth is created dynamically to approach the real conditions in VANET. The use of coefficients is further introduced to reduce cluster size according to the traffic conditions. The cluster management process uses a fully controlled Road Side Unit on the vehicle’s traffic conditions. In the final result, the convergence time is slightly faster, with better results in the throughput at 101.1%, the number of clusters at 58.1%, and the delay at 5.5%, respectively.

MATHEMATICAL MODELS PRODUCTIVITY OF CLUSTER SYSTEM BASED ON RASPBERRY PI 3B+

Context. High-performance computing systems are needed to solve many scientific problems and to work with complex applied problems. Previously, real parallel data processing was supported only by supercomputers, which are very limited and difficult to access. Currently, one way to solve this problem is to build small, cheap clusters based on single-board computers Raspberry Pi. Objective. The goal of the work is the creation of a complex criterion for the efficiency of the cluster system, which could properly characterize the operation of such a system and find the dependences of the performance of the cluster system based on Raspberry Pi 3B+ on the number of boards in it with different cooling systems. Method. It is offered to apply in the analysis of small cluster computer systems the complex criterion of efficiency of work of cluster system which will consider the general productivity of cluster computer system, productivity of one computing element in cluster computer system, electricity consumption by cluster system, electricity consumption per one computing element, the cost of calculating 1 Gflops cluster computer system, the total cost of the cluster computer system. Results. The developed complex criterion of cluster system efficiency was used to create an experimental cluster system based on single-board computers Raspberry Pi 3B+. Mathematical models of the dependence of the performance of a small cluster system based on single-board computers Raspberry Pi 3B+ depending on the number of boards in it with different cooling systems have also been developed. Conclusions. The conducted experiments confirmed the expediency of using the developed complex criterion of efficiency of the cluster system and allow to recommend it for use in practice when creating small cluster systems. Prospects for further research are to determine the weights of the constituent elements of the complex criterion of efficiency of the cluster system, as well as in the experimental study of the proposed weights.

Gastrointestinal manifestations of COVID-19 and possibility of feco-oral route of transmission

Covid-19 is a global health emergency originating from a small cluster of pneumonia like cases which spread to an extent to be regarded as a pandemic by WHO.in this review we discuss specifically the gastrointestinal manifestations of SARS CoV-2 positive patients in the published literature along with recent detection of SARS CoV-2 RNA in stool specimens and investigate the possible of feco oral route of viral transmission .

The store-operated Ca2+ entry complex comprises a small cluster of STIM1 associated with one Orai1 channel

Increases in cytosolic Ca2+ concentration regulate diverse cellular activities and are usually evoked by opening of Ca2+ channels in intracellular Ca2+ stores and the plasma membrane (PM). For the many signals that evoke formation of inositol 1,4,5-trisphosphate (IP3), IP3 receptors coordinate the contributions of these two Ca2+ sources by mediating Ca2+ release from the endoplasmic reticulum (ER). Loss of Ca2+ from the ER then activates store-operated Ca2+ entry (SOCE) by causing dimers of STIM1 to cluster and unfurl cytosolic domains that interact with the PM Ca2+ channel, Orai1, causing its pore to open. The relative concentrations of STIM1 and Orai1 are important, but most analyses of their interactions use overexpressed proteins that perturb the stoichiometry. We tagged endogenous STIM1 with EGFP using CRISPR/Cas9. SOCE evoked by loss of ER Ca2+ was unaffected by the tag. Step-photobleaching analysis of cells with empty Ca2+ stores revealed an average of 14.5 STIM1 molecules within each sub-PM punctum. The fluorescence intensity distributions of immunostained Orai1 puncta were minimally affected by store depletion, and similar for Orai1 colocalized with STIM1 puncta or remote from them. We conclude that each native SOCE complex is likely to include only a few STIM1 dimers associated with a single Orai1 channel. Our results, demonstrating that STIM1 does not assemble clusters of interacting Orai channels, suggest mechanisms for digital regulation of SOCE by local depletion of the ER.

Design and Implementation LETS (Low Power Cluster Server) for Sustaining UMKM during Pandemic

Covid pandemic is spreading since end 2019 arround globe, this resulting several countries suffer economic crisis. Due people movement restriction and international border is closed, impact halting on export and import. Indonesia with 267,7 million people manage to overcome global crisis during 1998 and 2008 with encourage small and local industry. According data from BPS, SME support 60% GDP with Rp 7,7 Billion and provide 85 million employment. To sustain SME during customer shifting behavior, we propose small cluster server called as LETS. LETS is modular, and composed with several Raspberry Pi 4, also consume few energies compared with traditional server. Although Raspberry Pi 4 is small size with few limitations, with lightweight application (ansible, k3s, and nginx) it can provide web server service. LETS provide handling traffic up to 742 simultaneus requests, which sufficient of SME requirement.