Production Turnover Research Articles

Collaborative system model construction and simulation optimization of e-commerce enterprise supply chain

ABSTRACT With the rise and rapid development of the e-commerce industry, the pressure borne by the supply chain of e-commerce enterprises is increasing, which greatly increases the complexity and uncertainty of inventory management in the e-commerce supply chain. The study integrates system dynamics and collaborative supply chain inventory management to construct a new model. The study first uses the concept of system dynamics to optimize the supply chain inventory management system; then the collaborative supply chain is used to construct a system model by combining the optimized management system. The results show that the collaborative supply chain inventory management model constructed by the study can better accelerate the product turnover rate, improve the overall operational efficiency and market competitiveness of the supply chain, and can provide new support for the development of e-commerce enterprises.

Organic fertilizer substitution benefits microbial richness and wheat yield under warming

Climate warming poses a serious threat to soil biodiversity and crop yield. Application of organic fertilizer has been extensively practiced to improve soil health and crop productivity. However, information is limited about the effects of organic fertilizer on microbial communities and diversity (richness) under warming. Thus, to investigate the interactive effects of temperature (ambient temperature and warming) and fertilizer (chemical fertilizer and partial substitution of chemical fertilizer with organic fertilizer) on microbial properties and wheat yield, a two-factorial pot experiment was conducted using soils with high and low fertility The results showed that warming and organic fertilizer had minor effects on bacterial Shannon and Simpson indexes. Due to concomitant reductions in soil moisture, warming decreased the average Chao index by 5.4 % and Ace index by 3.8 % for soils with high and low fertility (P < 0.05). High-throughput sequence presented that dominated genus was Bacillus with spore-forming ability. Under warming and drying conditions, microbes with adaptive traits (spore-forming ability) would outcompete the other microbes, and decrease microbial Chao and Ace index (richness). However, organic fertilizer counteracted the adverse effects of warming on microbial richness attributed to positive interaction between temperature and fertilizer on soil nutrients and organic carbon. The strong relationships between bacterial richness and wheat yield, as well as soil nutrients, highlighted the importance of soil biodiversity in improving soil nutrients and crop productivity. Partial substitution of chemical fertilizer with organic fertilizer significantly increased wheat yield by 27.1 % and 14.9 % under ambient temperature and by 28.0 % and 19.6 % under warming for soils with high and low fertility, respectively. Overall, this study provided the possibility to increase bacterial richness related to nutrient turnover and crop production by organic fertilizer application with reduced chemical fertilizer, especially under climate warming.

Prospects for the formation of a new approach to consumer spending in Russia

Introduction. The standard of living of the population, its dynamics are determined by a complex of indicators, among which are the population's expenditures. The structure of production and retail turnover largely depend on which groups of goods and services are in demand. At the same time, the directions of population expenditures are primarily determined by the size of their income and the socio-economic situation in the country and its regions. The aim of the research is to analyze the dynamics and structure of population expenditures in the Russian Federation. Materials. The research is based on the scientific articles from peer-reviewed journals, materials from scientific-practical conferences and seminars on the researched topic. Statistical data published by the Federal State Statistics Service (Rosstat) for the years 2019-2022 were used as the information base for the research. Results. A statistical analysis of the composition and structure of expenditures in Russian Federation population was carried out. The analyzed dynamics of the total amount of population expenditures included the main groups of consumer expenses. The main directions of optimizing population expenditures were identified. Conclusions. Preconditions for the formation of certain behavioral patterns and attitudes were identified among Russians characterized by increased attention to current consumption at the expense of resource accumulation. Measures of state policy in the field of increasing financial literacy of the population were considered, as well as the development of tools to optimize the tax base for certain categories of households, creating a favorable investment climate, and stimulating the growth of population incomes. The introduction of a new approach to consumer expenditures that ensures the formation of a "financial safety cushion" was considered as a tool to optimize population expenditures.

Distinct bacterial succession and functional response to alginate in the South, Equatorial, and North Pacific Ocean.

The availability of alginate, an abundant macroalgal polysaccharide, induces compositional and functional responses among marine microbes, but these dynamics have not been characterized across the Pacific Ocean. We investigated alginate-induced compositional and functional shifts (e.g., heterotrophic production, glucose turnover, hydrolytic enzyme activities) of microbial communities in the South Subtropical, Equatorial, and Polar Frontal North Pacific in mesocosms. We observed that shifts in response to alginate were site-specific. In the South Subtropical Pacific, prokaryotic cell counts, glucose turnover, and peptidase activities changed the most with alginate addition, along with the enrichment of the widest range of particle-associated taxa (161 amplicon sequence variants; ASVs) belonging to Alteromonadaceae, Rhodobacteraceae, Phormidiaceae, and Pseudoalteromonadaceae. Some of these taxa were detected at other sites but only enriched in the South Pacific. In the Equatorial Pacific, glucose turnover and heterotrophic prokaryotic production increased most rapidly; a single Alteromonas taxon dominated (60% of the community) but remained low (<2%) elsewhere. In the North Pacific, the particle-associated community response to alginate was gradual, with a more limited range of alginate-enriched taxa (82 ASVs). Thus, alginate-related ecological and biogeochemical shifts depend on a combination of factors that include the ability to utilize alginate, environmental conditions, and microbial interactions.

Nematode production in artificial ponds: a long-term perspective

Summary Nematodes are the most abundant multicellular animals on Earth and play an important role as intermediaries in energy fluxes. However, estimations of nematode biomass turnover and secondary production have been poorly defined for decades and it is difficult to reach a consensus about the importance of nematodes for ecosystem functioning. Here we monitored monthly the nematode species composition, abundance and biomass over 3-10 years in a set of artificial urban ponds, and we used different allometric models to estimate biomass turnover and secondary production. During the first 3 years of colonisation of the pond bottom, the nematode community was rather species-poor and mostly composed of small bacterivorous species (Monhysterids); however, the community quickly reached impressive numbers (up to 21 million individuals m−2) achieving a maximum annual production of 3.8-11.6 gC m−2 year−1 depending on the allometric model used for estimation. However, over the long-term (3-10 years), abundance and community structure eventually became dramatically altered by anoxic events occurring in one pond, dampening nematode production to low levels (0.3-0.6 gC m−2 year−1) without clear resilience. The comparison of models helped us to formulate general recommendations in order to popularise the use of nematode secondary production as a useful ecosystem diagnostic tool. Overall, results indicated that under good conditions of oxygenation nematodes are a highly productive component of the zoobenthos of ponds. We also discussed the consequences of this finding for sustainable pond aquaculture, as nematodes constitute an important local and nutritive resource for juveniles of economically important fish, such as carp and tilapia.

Evaluation of specific chicken IgY antibody value developing diagnostic capture antibody ELISA kit against Foot and Mouth disease.

The most preferred method for the detection of foot-and-mouth disease (FMD) viral antigen and identification of viral serotype is the enzyme-linked immunosorbent assay (ELISA). Diagnostic tests with high sensitivity are necessary both to distinguish infected vaccinated animals and execute disease control programs for the identification of the carrier animals. The current strategies for the detection of FMD virus are mainly based on the capture antibody (sandwich) ELISA test. The usage of laying pullets as an animal bioreactor for the production of specific egg yolk antibodies (IgY) has increased in recent years due to its high yield, affinity, low price, and quick production turnover. The present study aimed to produce a concentrated and purified IgY polyclonal antibody to design a capture antibody ELISA kit against the FMD virus (FMDV) serotype A. At first, laying hens were immunized with inactivated FMDV serotype virus, and then, on days 14, 21, and 28 following vaccination, the eggs and sera were collected. Afterward, the IgY polyclonal antibodies were extracted and purified from the chicken egg yolk using a polyethylene glycol 6000-ethanol precipitation procedure. Extracts were filtered, purified by ion exchange chromatography, and dialyzed. The purified IgY concentration, estimated by Bradford assay, confirmed its presence by SDS-PAGE and Western blot and also its specific immune reaction by Ouchterlony double immunodiffusion and Dot blot tests. Moreover, for achieving the optimum concentration of antigen/antibody (sera) in sandwich ELISA, a checkerboardtitrationtest was set up based on indirect ELISA results. Eventually, 119 previously confirmed samples (including 80 positive and 39 negative) by both real-time polymerase chain reaction (quantitative PCR, qPCR) and a commercial ELISA kit were used for evaluation of the sensitivity and accuracy of our developed Capture antibody ELISA kit. In this manner, the sensitivity and specificity of our designed kit were 100% and 98%, respectively. Accordingly, the present developed capture ELISA kit based on IgY had high sensitivity and specificity for FMD virus detection and it could be used in the future for both commercial detecting and serotyping applications.

Pemberdayaan ekonomi masyarakat desa kayulaut melalui UMKM komunitas kue khas Bika bakar kayulaut dengan strategi culinary fashion

This Community Service is carried out by Lecturer of English Tadris Study Program STAIN Madina and Sharia Economics Lecturer Stain Madina with the method of Asset Based Community Development (ABCD). The implementation of Community Service is supported by various parties, in this case the Head of Kayulaut Village and Naposo Nauli Bulung of Kayulaut Village. And the Kayulaut Bika Bakar Cake MSME Community One of the reasons for choosing this village is because Kayulaut Village has the potential for a prosperous life through traditional bika bakar cake cooking skills by its residents, but it is known that in recent years the sales turnover of Bika Bakar Cake producers has decreased drastically due to several things, including packaging that still uses plastic bags and limited marketing access. Partner products cannot compete with modern pastry products made by already large businesses because there is not enough promotion. Partners still use simple tools – causing fatigue because they are continuously around the fire stove, so that the production of bika bakar produced is not optimal in quantity or quality.so that Kue Bika Bakar Kayulaut no longer meets trade turnover like a few years ago. The stages of Community Service carried out are divided into three stages, namely; Socialization of Program Activities, Implementation and Evaluation. Community Service Lasted from 08.00 WIB until it was completed for three days starting from the preparation of the activity, attended by 70 participants. The subject matter conveyed Through this activity; Logo / branding, packaging, and e-commerce. With the Community Service activities, the economic empowerment of the Kayulaut village community through MSMEs of the typical Bika bakar kayulaut cake community with a culinary fashion strategy is expected to increase the production turnover of Kayulaut Bika Bakar Cake so that the people of Kayulaut Village are more prosperous as MSME actors of Kayulaut Cake.

Daily turnover of active giant virus infection during algal blooms revealed by single-cell transcriptomics.

Giant viruses infect many unicellular eukaryotes, including algae that form massive oceanic blooms. Despite the major impact of viruses on the marine ecosystem, the ability to quantify and assess active viral infection in nature remains a major challenge. We applied single-cell RNA sequencing, to profile virus and host transcriptomes of 12,000 single algal cells from a coccolithophore bloom. Viral infection was detected already at early exponential bloom phase, negatively correlating with the bloom intensity. A consistent percent of infected coccolithophores displayed the early phase of viral replication for several consecutive days, indicating a daily turnover and continuous virocell-associated metabolite production, potentially affecting the surrounding microbiome. Linking single-cell infection state to host physiology revealed that infected cells remained calcified even in the late infection stage. These findings stress the importance of studying host-virus dynamics in natural populations, at single-cell resolution, to better understand virus life cycle and its impact on microbial food webs.

Trophic distribution of nutrient production in coral reef fisheries.

Coral reef fisheries supply nutritious catch to tropical coastal communities, where the quality of reef seafood is determined by both the rate of biomass production and nutritional value of reef fishes. Yet our understanding of reef fisheries typically uses targets of total reef fish biomass rather than individual growth (i.e. biomass production) and nutrient content (i.e. nutritional value of reef fish), limiting the ability of management to sustain the productivity of nutritious catches. Here, we use modelled growth coefficients and nutrient concentrations to develop a new metric of nutrient productivity of coral reef fishes. We then evaluate this metric with underwater visual surveys of reef fish assemblages from four tropical countries to examine nutrient productivity of reef fish food webs. Species' growth coefficients were associated with nutrients that vary with body size (calcium, iron, selenium and zinc), but not total nutrient density. When integrated with fish abundance data, we find that herbivorous species typically dominate standing biomass, biomass turnover and nutrient production on coral reefs. Such bottom-heavy trophic distributions of nutrients were consistent across gradients of fishing pressure and benthic composition. We conclude that management restrictions that promote sustainability of herbivores and other low trophic-level species can sustain biomass and nutrient production from reef fisheries that is critical to the food security of over 500 million people in the tropics.

Russia–Ukraine war: A note on short-run production and labour market effects of the energy crisis

We provide first causal evidence of effects of the energy crisis on Germany, the largest economy in Europe. Combining cost structure data, national accounts and administrative labour market data, we identify effects in a sectoral panel setting using sector-specific energy intensity as a “bite” variable. The results show that through the channel of energy intensity, monthly production and real turnover decreased by 4.1 and 2.6 per cent, respectively, after the onset of the Russia–Ukraine war. Instead of layoffs, firms safeguarded employment by means of short-time work, with a 24.1 per cent increase in notifications. Vacancy posting was reduced by 10.3 per cent.

ВЛИЯНИЕ МЕХАНИЗМА РАСШИРЕННОЙ ОТВЕТСТВЕННОСТИ ПРОИЗВОДИТЕЛЕЙ НА СОСТОЯНИЕ ИНДУСТРИИ ВТОРИЧНЫХ МАТЕРИАЛОВ В РЕГИОНАХ РОССИИ

The article gives a description of the current situation with the introduction of extended producer responsibility in the Russian sphere of waste management. The authors show that at this stage there are a number of problems with the involvement of secondary resources in the production turnover. As a theoretical significance of the study, it should be noted the model developed by the authors of a comprehensive accounting of the components of the organizational and economic mechanism of extended producer responsibility in the regions of Russia (POETIC). Of practical interest are recommendations for the implementation of this model.

ORGANIC SUPPLY CHAIN MANAGEMENT PRODUCTS IN FOOD CLUSTERS: REGIONAL ASPECT

Background. A number of organizations interact in the supply chain of organic products - manufacturers, warehouses, distributors, carriers, wholesale and retail buyers involved in the formation of material, financial, information and service flows from the source of raw materials to the final consumer.&#x0D; Purpose. It consists in the development of principles of supply chain management of organic products in the food system of the region&#x0D; Materials and methods. The methodological and theoretical basis of the research was the work of domestic and foreign scientists on the management of the supply of organic products in regional food systems. In particular, for a practical example, the Altai Territory was chosen as an ecologically clean region with sufficient land, labor and production resources for the development of organic agricultural production and processing of organic products. In the course of the work, analytical, abstract-logical, monographic and other research methods were applied.&#x0D; Results. It is advisable to manage the promotion of organic products in the food system of the region with the help of innovative digital technologies, in particular blockchain, as well as through the system of agricultural information and consulting centers, organization of presentations of organic products, advertising campaigns, participation in exhibitions and fairs at the regional and Russian levels, the opening of "green" shelves by retailers in their networks. The development of organic agriculture in the Altai Territory can have a significant positive effect on the level of economic, social and environmental development of rural areas of the region by activating the regional market of organic agricultural products, involving unused land resources in the production turnover, using innovative technologies in the agro-industrial complex, increasing the employment of rural residents, activating the ecotourism sphere, increasing the economic sustainability of agro-industrial organizations region.&#x0D; Conclusion. The development of integrated solutions to these problems with the proper level of coordination of all participants in the supply chain of organic products contribute to the formation of a developing global market for organic raw materials and food, affecting agricultural production models, distribution of income and costs, the introduction of digital technology innovations, the greening of the agro-industrial sector, the development of the economy of agricultural regions.

The deficiency of poly-β-1,6-N-acetyl-glucosamine deacetylase trigger A. baumannii to convert to biofilm-independent colistin-tolerant cells

Acinetobacter baumannii is a nosocomial pathogen that can be resistant to antibiotics by rapidly modulating its anti-drug mechanisms. The multidrug-resistant A. baumannii has been considered one of the most threatening pathogens to our society. Biofilm formation and persistent cells within the biofilm matrix are recognized as intractable problems, especially in hospital-acquired infections. Poly-β-1,6-N-acetyl-glucosamine (PNAG) is one of the important building blocks in A. baumannii’s biofilm. Here, we discover a protein phosphoryl-regulation on PNAG deacetylase, AbPgaB1, in which residue Ser411 was phosphorylated. The phosphoryl-regulation on AbPgaB1 modulates the product turnover rate in which deacetylated PNAG is produced and reflected in biofilm production. We further uncovered the PgaB deficient A. baumannii strain shows the lowest level of biofilm production but has a high minimal inhibition concentration to antibiotic colistin and tetracycline. Based on bactericidal post-antibiotic effects and time-dependent killing assays with antibacterial drugs, we claim that the PgaB-deficient A. baumannii converts to colistin-tolerant cells. This study utilizes a biofilm-independent colistin-tolerant model of A. baumannii to further investigate its characteristics and mechanisms to better understand clinical outcomes.

Near-unity electrochemical conversion of nitrate to ammonia on crystalline nickel porphyrin-based covalent organic frameworks

A novel 2D nickel porphyrin-based covalent organic framework is fabricated as an efficient nitrate reduction electrocatalyst that shows a great selectivity of ∼90% under a mild overpotential with a remarkable production rate and turnover frequency.

Towards process-oriented management of tropical reefs in the anthropocene

Tropical reefs and the fish relying on them are under increasing pressure. Shallow-reef fish provide important ecological information in addition to sustaining fisheries, tourism and more. Although empirical metrics of fish biomass are widely used in fisheries management, metrics of biomass production—how much new biomass is produced over time—are rarely estimated even though such production informs potential fisheries yields. Here we estimate fish standing biomass (B), biomass production (P, the rate of biomass accumulation) and biomass turnover (P/B ratio, the rate of biomass replacement) for 1,979 tropical reef sites spanning 39 tropical countries. On the basis of fish standing biomass and biomass turnover, we propose a conceptual framework that splits reefs into three classes to visualize ecological and socio-economic risk and help guide spatial management interventions (for example, marine protected areas) to optimize returns on conservation efforts. At large scales, high turnover was associated with high human pressure and low primary productivity, whereas high biomass was associated with low human pressure and high primary productivity. Going beyond standing fish biomass to consider dynamic ecological processes can better guide regional coral reef conservation and sustainable fisheries management.

Hetero‐Atomic Pairs with a Distal Fe3+‐Site Boost Water Oxidation

AbstractThe hetero‐atomic interaction has been the subject of many investigations, due to their heterogeneity, the individual roles of the atoms are still difficult to realize. Herein, an electrocatalyst with a hetero‐atomic pair confined on a tungsten phosphide (WP) substrate so that the Fe3+‐site of the pair is distal to the surface is shown to deliver an extremely low overpotential of 192 mV at 10 mA cm−2 and one of the highest oxygen production turnover frequencies (TOF) of 2.1 s−1 at 300 mV under alkaline environment for the oxygen evolution reaction (OER). Operando characterization shows the Lewis acidic Fe3+ site boosts a large population of Co4+/3+ and the deprotonation of coordinated water, allowing simultaneously enhanced electron‐transfer as well as the proton‐transfer. A significant contribution from the WP substrate modulates the order of hydroxide transfer in the pre‐equilibrium step (PES) and rate‐determining‐step (RDS), leading to a remarkable OER performance.

Hetero-Atomic Pairs with a Distal Fe3+ -Site Boost Water Oxidation.

The hetero-atomic interaction has been the subject of many investigations, due to their heterogeneity, the individual roles of the atoms are still difficult to realize. Herein, an electrocatalyst with a hetero-atomic pair confined on a tungsten phosphide (WP) substrate so that the Fe3+ -site of the pair is distal to the surface is shown to deliver an extremely low overpotential of 192 mV at 10 mA cm-2 and one of the highest oxygen production turnover frequencies (TOF) of 2.1 s-1 at 300 mV under alkaline environment for the oxygen evolution reaction (OER). Operando characterization shows the Lewis acidic Fe3+ site boosts a large population of Co4+/3+ and the deprotonation of coordinated water, allowing simultaneously enhanced electron-transfer as well as the proton-transfer. A significant contribution from the WP substrate modulates the order of hydroxide transfer in the pre-equilibrium step (PES) and rate-determining-step (RDS), leading to a remarkable OER performance.

VP.86 Effect of a chronic treatment with L-citrulline on funtional, histological and molecular readouts of dystrophic mdx mouse model

The absence of protein dystrophin in Duchenne muscular dystrophy leads to progressive muscle weakness and wasting, paralleled by failing regeneration. Recently, a key role of deregulated nitric oxide production in epigenetic control of regeneration program has been demonstrated. We focused on the potential interest of the amino acid L-citrulline (L-Cit), a precursor of L-arginine, physiologically required for protein turnover and nitric oxide production in muscle and blood vessels. We administered L-citrulline (2 mg/g/die), through diet, alone or in combination with PDN, (1 mg/kg, 5 days/week subcutaneously) to 4-5 week-old mdx mice for 8 weeks. We found that the increment of maximal forelimb strength was improved in all treated groups vs. untreated mdx mice, particularly by L-Cit alone or with PDN. Ex vivo, treated mdx mice displayed a significant increase of specific isometric twitch and tetanic force in diaphragm (DIA), with minor effects in extensor digitorum longus muscle. Additionally, L-Cit, alone or in combination with PDN, reduced fibrosis and inflammation in gastrocnemius and DIA muscles, and decreased plasma levels of lactate dehydrogenase. PCR analysis in muscles is currently ongoing. These data are encouraging regarding the potential benefits of L-Cit supplementation in DMD also in combination with standard therapy (NL-DPP grant).

Plant traits and environment: floating leaf blade production and turnover of Nymphoides peltata (S.G. Gmel.) O. Kuntze (Menyanthaceae).

BackgroundNymphaeid macrophytes, rooting in the sediment of water bodies and characterized by floating leaves, play an important role in wetland ecosystems. The present research deals with the effects of limited space, limited nutrient availability, water temperature and an unexpected inundation on the production, turnover and plasticity of floating leaves of the globally widespread species Nymphoides peltata (Fringed waterlily).MethodsThe effects of these environmental conditions were studied in two plots in outdoor concrete tanks (CT1, CT2, mesocosms simulating occurrence in small ponds) and in two plots in the floodplain oxbow lake Bemmelse Strang (BS1, BS2). Plot CT1 was situated in a stand coexisting with helophytes, plot CT2 in a monospecific stand, plot BS1 in the center and plot BS2 at the open water border of a monospecific stand. All floating leaf blades within the plots were marked at appearance at the water surface and subsequently length, width and damage of each leaf and maximum and minimum water temperatures were measured bi-weekly. Area and biomass of leaf blades were calculated based on leaf length and width and were used to calculate turnover rates and production.ResultsThe growth period started in May and ended mid-October with continuous production of floating leaves during nearly the whole vegetation period. In the tanks the water level was very stable, but the lake underwent an inundation by river water, causing a sudden loss of existing leaves. Considering environmental conditions and based on the assumed ranking from low to high nutrient availability, the ranking of the plots was CT1, CT2, BS1, BS2. This order was found for maximum leaf life span and maximum leaf length, and the reverse order was found for number of leaves, new leaves per day and duration of the vegetation period. Turnover rates appeared to be relatively similar for plots CT1, CT2 and BS1, but for the deeper border plot BS2 lower ratios were found. These results indicate that increased enclosure with expected nutrient limitation causes (1) the production of high numbers of small leaves with larger totals for leaf area and biomass, (2) a shift towards increased sexual reproduction by the production of more flowering stem leaves.

Rhizomes play significant roles in biomass accumulation, production and carbon turnover in a stand of the tall bamboo Phyllostachys edulis

ABSTRACT Phyllostachys edulis (Poales: Poaceae) is a bamboo species with well-developed rhizomes, which play important roles in growth, resource storage and transport. However, the extent to which rhizomes are produced, accumulated and turn over annually at the stand level remains largely unknown. We studied the biomass, production and turnover rate of rhizomes and other organs (culms, branches, leaves and roots) in a bamboo stand in Japan between 2013 and 2018. We sought to answer the following questions: To what extent is the newly assimilated carbon allocated to rhizomes, and how rapid is carbon turnover in rhizomes? How does biomass allocation to below-ground parts in bamboo ramets compare to that in woody plant individuals of similar size? We found the amount of newly produced rhizomes was 0.90 Mg C ha–1 year−1, which accounted for 9.5% of total new biomass. The carbon turnover rate of rhizomes was 0.11 g g−1 year−1, which was slower than that of other organs (i.e. longer lifespan). Compared to other woody plants of similar biomass, bamboo had 2.0-fold higher biomass allocation to below-ground organs due to the high biomass of rhizomes. Furthermore, bamboo allocated 8.7-fold lower biomass to leaves despite their high growth rates, perhaps due to the thin (but leathery) leaves and green stems that can photosynthesize as well. Our study highlights that the large storage capacity of below-ground rhizomes along with the efficient above-ground production system are the key growth features of P. edulis, which are likely to contribute to their success in temperate forests.