Block-STM Scaling Blockchain Execution by Turning Ordering Curse to a Performance Blessing

Block-STM is a parallel execution engine for smart contracts, built around the principles of Software Transactional Memory. Transactions are grouped in blocks, and every execution of the block must yield the same deterministic outcome. Block-STM further enforces that the outcome is consistent with executing transactions according to a preset order, leveraging this order to dynamically detect dependencies and avoid conflicts during speculative transaction execution. At the core of Block-STM is a novel, low-overhead collaborative scheduler of execution and validation tasks. Block-STM is implemented on the main branch of the Diem Blockchain code-base and runs in production at Aptos. Our evaluation demonstrates that Block-STM is adaptive to workloads with different conflict rates and utilizes the inherent parallelism therein. Block-STM achieves up to 110k tps in the Diem benchmarks and up to 170k tps in the Aptos Benchmarks, which is a 20x and 17x improvement over the sequential baseline with 32 threads, respectively. The throughput on a contended workload is up to 50k tps and 80k tps in Diem and Aptos benchmarks, respectively

Floating marine macro litter in the Black Sea: Toward baselines for large scale assessment

The Black Sea is a semi-enclosed basin subject to major anthropogenic pressures, including marine litter and plastic pollution. Due to numerous large rivers draining into the basin and a population settled along the coast, the region could accumulate significant amounts of floating litter over time. Until now, only limited field data were available, and litter quantities and distribution remained unknown. In this study, floating marine macro litter (FMML) was assessed at the regional Black Sea scale for the first time, showing relatively high litter densities across the basin that reached a weighted mean of 81.5 items/km(2). Monitoring data revealed an accumulation of floating items offshore in the eastern part of the basin, resembling on a small scale a "garbage patch', where litter items were trapped, showing elevated densities in comparison to their surrounding areas. Most of these items were made of plastic materials (ca. 96%) and included large numbers of plastic and poly-styrene fragments of small size ranges (2.5-10 cm). Harmonised field data collection through consistent and regular monitoring programmes across the region is essential to establish baselines and thresholds for large scale assessment at international level

Non-interventional (observational) study of application of the tamsulosin (Proflosin®) in patients with benign prostatic hyperplasia in routine clinical practice

The problem of therapy of benign prostatic hyperplasia has not lost its relevance today due to the high prevalence rate of this pathologyamong the male population. The article provides the results of non-interventional (observational) study of application of the tamsulosin(Proflosin®) drug or combined therapy with tamsulosin (Proflosin®) + Serenoa repens (Prostamol® Uno) of patients with benign prostatic hyperplasia in routine clinical practice. 1,000 practicing urology experts from 100 cities and towns of Russia took part in the study as well as 23 492 patients with the established diagnosis of benign prostatic hyperplasia, which were prescribed with tamsulosin (Proflosin®) monotherapy or combined therapy with tamsulosin (Proflosin®) + Serenoa repens (Prostamol® Uno) in conditions of outpatient clinical practice. As a result of the study, improvement of the life standard and subjective symptoms were stated with patients with the absence of significant side effects directly associated with intake of the drug studies.</p

Fractal characteristics of the species structure of ichneumon wasp communities in the middle urals

09 04 97086ACKNOWLEDGMENTS This study was supported by the Russian Founda tion for Basic Research, project no. 09 04 97086