The effect of a complex additive on the structure formation of cement stone in conditions of dry hot climate and saline soils

In DHC and saline soils and groundwater conditions, the cement mix quickly loses its mobility and workability. In this regard, it is necessary to plasticize it by introducing various surfactants. However, the surfactant additive used should not slow down the process of hydration and hardening. To ensure salt resistance, it is necessary to increase the density and the strength of concrete. The proposed complex additive was obtained by joint grinding in a ball mill of a soda-sulfate alloy (SSA) and gossypol resin (GR) to a specific surface area of 2800 cm2/g at the rate of 05, -1.5%, and 0.1-0.3%, respectively, of the cement mass. The complex additive was introduced into the mixing water of the cement mix. From the research results obtained, it is seen that with an increase in the content of GR from 0.1 to 0.3%, the normal density decreases by 1.4-4 points, and the setting time (due to the accelerating action of the SSA) decreases at the beginning by 20-50 minutes, and at the end by 60-240 minutes. In 28 days, the control cement gained the strength of 56 MPa, and with a complex addition - 60-68 MPa. The introduction of a complex additive led to an increase in the salt resistance coefficient in the reference cement up to 0.55-0.65, and in the cement with a complex additive up to 0.80-0.86; an increase was observed due to the strength and density of the samples. By increasing the strength, it is possible to save 17-21% of cement

Influence of type of modified fillers based on dune sand on properties of cement paste, stone, and on technological and strength properties of concrete

Industrial enterprises are being built on a large scale in the desert regions of Uzbekistan. Concrete remains the main material in construction to this day. However, there is an acute shortage of sand of normal size. In this regard, an urgent task is to find effective and affordable technological methods for improving the properties of cement paste, concrete mix, and concrete on dune sand and cement savings. Taking into account our previous studies, the main attention was paid to establishing quantitative dependencies, changing the properties of cement paste and concrete from the introduction of sand dune fillers modified with additives of acidic (SDFMAA) and basic (marl) nature into their composition and the influence of methods for preparing a mixture of conventional and separate

Persistent parental RNAi in the Beetle Tribolium castaneum involves maternal transmission of long double‐stranded RNA

Parental RNA interference (pRNAi) is a powerful and widely used method for gene‐specific knockdown. Yet in insects its efficacy varies between species, and how the systemic response is transmitted from mother to offspring remains elusive. Using the beetle Tribolium castaneum, an RT‐qPCR strategy to distinguish the presence of double‐stranded RNA (dsRNA) from endogenous mRNA is reported. It is found that injected dsRNA is directly transmitted into the egg and persists throughout embryogenesis. Despite this depletion of dsRNA from the mother, it is shown that strong pRNAi can persist for months before waning at strain‐specific rates. In seeking the receptor proteins for cellular uptake of long dsRNA into the egg, a phylogenomics profiling approach of candidate proteins is also presented. A visualization strategy based on taxonomically hierarchical assessment of orthology clustering data to rapidly assess gene age and copy number changes, refined by sequence‐based evidence, is demonstrated. Repeated losses of SID‐1‐like channel proteins in the arthropods, including wholesale loss in the Heteroptera (true bugs), which are nonetheless highly sensitive to pRNAi, are thereby documented. Overall, practical considerations for insect pRNAi against a backdrop of outstanding questions on the molecular mechanism of dsRNA transmission for long‐term, systemic knockdown are elucidated

The dual PI3K/mTOR inhibitor GSK2126458 is effective for treating solid renal tumours in Tsc2+/- mice through suppression of cell proliferation and induction of apoptosis

Tuberous sclerosis (TSC) is an inherited tumour syndrome caused by mutations in TSC1 or TSC2 that lead to aberrant activation of mTOR. Tumour responses in TSC patients to rapamycin, an allosteric inhibitor of mTOR, or its analogs are partial and reversible probably due to feedback activation of Akt. In this study, we examined the efficacy of GSK2126458, an ATP-competitive dual inhibitor of PI3K/mTOR, in comparison to rapamycin for treatment of renal tumours in genetically engineered Tsc2+/- mice. We found that both GSK2126458 and rapamycin caused significant reduction in number and size of solid renal tumours. GSK2126458 also significantly reduced the number and size of all lesions (cystic, papillary and solid) although to a lesser extent compared to rapamycin. GSK2126458 inhibited both PI3K and mTOR while rapamycin exerted stronger inhibitory effect on mTORC1 in renal tumours. Furthermore, GSK2126458 and rapamycin suppressed proliferation of tumour cells. Importantly, GSK2126458 increased apoptosis of solid tumours but rapamycin did not. Further investigations are therefore needed to test whether rapamycin in combination with GSK2126458 could promote apoptosis and thus improve therapy of TSC-associated renal tumours

Efficacy of dual inhibition of glycolysis and glutaminolysis for therapy of renal lesions in Tsc2+/− Mice1

Tuberous sclerosis is caused by mutations in the TSC1 or TSC2 gene and characterized by development of tumors in multiple organs including the kidneys. TSC-associated tumors exhibit somatic loss of the second allele of the TSC genes, leading to aberrant activation of the mechanistic target of rapamycin (mTOR) signaling pathway. Activation of mTOR complex 1 (mTORC1) causes addiction to glucose and glutamine in Tsc1−/−or Tsc2−/− mouse embryonic fibroblasts (MEFs). Blocking of glutamine anaplerosis in combination with glycolytic inhibition causes significant cell death in Tsc2−/− but not Tsc2+/+ MEFs. In this study, we tested efficacy of dual inhibition of glycolysis with 3-BrPA and glutaminolysis with CB-839 for renal tumors in Tsc2+/− mice. Following 2 months of treatment of Tsc2+/− mice from the age of 12 months, combination of 3-BrPA and CB-839 significantly reduced overall size and cellular areas of all renal lesions (cystic/papillary adenomas and solid carcinomas), but neither alone did. Combination of 3-BrPA and CB-839 inhibited mTORC1 and the proliferation of tumor cells but did not increase apoptosis. However, combination of 3-BrPA and CB-839 was not as efficacious as rapamycin alone or rapamycin in combination with either 3-BrPA or CB-839 for renal lesions of Tsc2+/− mice. Consistently, rapamycin alone or rapamycin in combination with either 3-BrPA or CB-839 had stronger inhibitory effects on mTORC1 and proliferation of tumor cells than combination of 3-BrPA and CB-839. We conclude that combination of 3-BRPA and CB-839 may not offer a better therapeutic strategy than rapamycin for TSC-associated tumors

Assessment of response of kidney tumours to rapamycin and atorvastatin in Tsc1+/- mice

Atorvastatin is widely used to lower blood cholesterol and to reduce risk of cardiovascular disease–associated complications. Epidemiological investigations and preclinical studies suggest that statins such as atorvastatin have antitumor activity for various types of cancer. Tuberous sclerosis (TSC) is a tumor syndrome caused by TSC1 or TSC2 mutations that lead to aberrant activation of mTOR and tumor formation in multiple organs. Previous studies have demonstrated that atorvastatin selectively suppressed growth and proliferation ofmouse Tsc2 null embryonic fibroblasts through inhibition ofmTOR. However, atorvastatin alone did not reduce tumor burden in the liver and kidneys of Tsc2+/− mice as assessed by histological analysis, and no combination therapy of rapamycin and atorvastatin has been tried. In this study, we used T2-weightedmagnetic resonance imaging to track changes in tumor number and size in the kidneys of a Tsc1+/− mousemodel and to assess the efficacy of rapamycin and atorvastatin alone and as a combination therapy. We found that rapamycin alone or rapamycin combined with atorvastatin significantly reduced tumor burden, while atorvastatin alone did not. Combined therapy with rapamycin and atorvastatin appeared to be more effective for treating renal tumors than rapamycin alone, but the difference was not statistically significant. We conclude that combined therapy with rapamycin and atorvastatin is unlikely to provide additional benefit over rapamycin as a single agent in the treatment of Tsc-associated renal tumors

Allosteric and ATP-competitive inhibitors of mTOR effectively suppress tumor progression-associated epithelial-mesenchymal transition in the kidneys of Tsc2+/− Mice

In tuberous sclerosis (TSC)–associated tumors, mutations in the TSC genes lead to aberrant activation of the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway. mTORC1 signaling impacts many biological processes including the epithelial-mesenchymal transition (EMT), which is suggested to promote tumor progression and metastasis in various types of cancer. In this study, we report hybrid cells with epithelial and mesenchymal features in angiomyolipomas and partial EMT in carcinomas from TSC patients and describe a new model of EMT activation during tumor progression from cyst to papillary adenoma to solid carcinoma in the kidneys of Tsc2+/− mice. Features of EMT occurred infrequently in TSC-associated cysts but increased as the lesions progressed through papillary adenoma to solid carcinoma where epithelial-mesenchymal hybrid cells were abundant, indicating partial EMT. We also compared the effects of the novel ATP-competitive mTOR inhibitor AZD2014 with the allosteric mTOR inhibitor rapamycin on EMT and tumor burden. Both AZD2014 and rapamycin potently suppressed EMT of renal tumors and effectively blocked tumor progression in Tsc2+/− mice. These results suggest that partial EMT is a shared feature of TSC-associated renal tumors in humans and mice and occurs during TSC-associated tumor progression. EMT-related signaling pathways may represent therapeutic targets for tumors associated with mutations in the TSC genes

БЛИЖАЙШИЕ РЕЗУЛЬТАТЫ МУЛЬТИМОДАЛЬНОГО ЛЕЧЕНИЯ АДЕНОКАРЦИНОМЫ ПРЕДСТАТЕЛЬНОЙ ЖЕЛЕЗЫ В НОВОСИБИРСКОЙ ОБЛАСТИ

The short-term performance criteria (PSA blood level and prostate volume) were analyzed concerning the complex (hormonal and radiation) treatment of 57 patients with prostate adenocarcinoma, stratified into three disease progression risk groups. Two treatment regimens were differed in the duration of neoadjuvant hormone therapy: 9 or 32 ± 13 months in combination with external beam radiation therapy with a total dose 76–80 Gy. Statistical analysis of the multimodal treatment efficiency criteria of patients with high risk of prostate adenocarcinoma showed the best result (significant decrease of PSA blood level) using a single 9-month course of hormone therapy and subsequent external beam radiation therapy. The prostate volume indicator in the applicable mode of radiation therapy has mixed dynamics, and requires further study as a multimodal treatment effectiveness criterion.Изучены ближайшие критерии эффективности – уровень простатспецифического антигена (ПСА) и объем предстательной железы (ПЖ) – комплексного (гормонального и лучевого) лечения 57 пациентов с аденокарциномой ПЖ, стратифицированных по 3 группам риска прогрессирования заболевания. Использованы 2 схемы лечения, различающиеся по длительности неоадъювантной гормонотерапии: 9 мес или 32 ± 13 мес в сочетании с дистанционной лучевой терапией с суммарной дозой 76–80 Гр. У пациентов с высоким риском прогрессирования опухолевого процесса продемонстрирована достоверно высокая эффективность комбинированного метода лечения с наилучшими показателями снижения уровня ПСА в группе 9-месячного курса гормонотерапии. Показатель объема органа в применяемом режиме лучевой терапии имеет разнонаправленную динамику и требует дальнейшего изучения в качестве критерия эффективности мультимодального лечения

Development of intensive technology for constructing low-rise building walls from ash-cement mix

There is a great demand for low-rise construction in Uzbekistan. In this regard, it is necessary to continue research on the intensification of the technology of monolithic low-rise housing construction using primarily local waste from various industries. One of them is fly ash waste from the electric power industry. It is proposed to use fly ash as a filler in a cement-ash composition, and it is considered more affordable. The use of other industrial waste as fillers requires additional special processing such as drying and grinding. It was established that fly ash is more accessible for practical use. From the point of view of the structural theory of composite building materials, fly ash has a plasticizing ability, which in turn helps to reduce water consumption. It was established that it is appropriate to use mineral additives in combination with other additives in the preparation of concrete mixes with high workability and low cement consumption. To determine the strength properties, samples were prepared from an ash-cement mix with a water-cement ratio of 0.32, with a fly ash content of 85% of the total mass of the mix. The hardener additive (soda powder) was used at 1.5% by weight of the binder and activated in the mixers for 2 -4 minutes. The results of the study show that the additive accelerates the hardening process of the ash-cement mix by 80-90% at one day of age, due to activation, the strength increases by 11-22% for the mix with/without the additive, respectively. When the mix is activated, the particles are struck and the inert film is torn off from their surface and free access of water to the ash particles is ensured; this, in turn, leads to an increase in the number of hydrate formations and a deeper occurrence of hydration processes. We studied the effect of the sequence of loading components in a working mixer on strength indices. The strength of the mechanically activated mix with 80% fly ash content and 1.5% addition of soda powder, reached 18.5-19.5 MPa. An ash-cement mix for concreting monolithic low-rise buildings was developed

TECHNOLOGY OF FASTENING METAL COLUMNS AND PLACES ADJACENT TO THE FOUNDATION WITH BOLTS

The strength, connection of junctions and stability of the erected buildings and construction depends on the quality of the seaming of the joints of the steel structure. The connection of junctions consists of the following processes: welding, protection against corrosion and concreting, applying protective coverings