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1.
J Environ Manage ; 353: 120225, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38330837

RESUMO

China's growing demand for bulk chemicals and concerns regarding energy security are scaling up coal-to-olefins (CTO) production. Three generations of independent dimethyl ether/methanol-to-olefins technologies have been successively launched with greatly improved production efficiencies. However, to date, widespread concerns regarding the intensive environmental impacts and potential economic risks have not been addressed in the context of this industrialization. Here we show that, through the technological progress from the first to the third generation, life cycle energy consumption, water consumption, and carbon emissions can be reduced to 119.5 GJ/t, 27.6 t/t, and 9.1 t CO2-eq/t, respectively, and human health damage, ecosystem quality damage, and resource scarcity impacts can be decreased by 40.5 %, 50.1 %, and 16.4 %, respectively. This is accompanied by an excellent performance in terms of production cost, net present value, and internal return rate at 792.5 USD/t, 173.4 USD/t, and 19.4 %, respectively. Substantial environmental and economic benefits can be gained by coupling renewables in the form of using green hydrogen from solar and wind power to synthesize methanol. Particularly, life cycle carbon emissions and resource scarcity impacts are reduced by 23.4 % and 22.4 %, respectively, exceeding the reduction in technological progress. However, coupling renewables increases the life cycle energy consumption to 154.5 GJ/t, counteracting the benefits of technological progress. Our results highlight the importance of technological progress and coupled renewables for enhancing the sustainability of the CTO industry.


Assuntos
Alcenos , Carvão Mineral , Humanos , Ecossistema , Metanol , Desenvolvimento Econômico , Carbono/análise , Dióxido de Carbono/análise , China
2.
Heliyon ; 10(4): e25742, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384540

RESUMO

This study aims to determine the most cost-effective approach for production of green hydrogen, a crucial element for global decarbonization efforts despite its high production costs. The primary research question addresses the optimal and economically viable strategy for green hydrogen production considering various scenarios and technologies. Through a comprehensive analysis of eight scenarios, the study employs economic parameters such as net present value, minimum production cost, payback period and sensitivity analysis. The analysis is validated using established economic metrics and real-world considerations to ensure feasibility. The results suggest that a hybrid system combining solar photovoltaic (PV) with storage and onshore wind turbines is a promising approach yielding a minimum cost of $3.01 per kg of green hydrogen, an internal rate of return (IRR) of 5.04% and 8-year payback period. These findings provide a practical solution for cost-effective green hydrogen production supporting the transition to sustainable energy sources. The study also highlights the future potential of integrating solar thermal (CSP) with an organic Rankine cycle (ORC) system for waste heat recovery in hydrogen production. The sensitivity analysis provides the importance of capacity factor, levelized cost of hydrogen, capital expenditure and discount rate in influencing production costs.

3.
J Environ Manage ; 347: 119102, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37793291

RESUMO

Due to high material density, high energy consumption density and CO2 emission density, it is not only difficult but significant to clarify the relationship between energy consumption, the CO2 emission and the production cost in different conditions. However, the previous researches rarely refer how to balance the energy consumption, the CO2 emission and the production cost after the fluctuation of material, energy and carbon price as well as what will happen to them if production structure changes. Therefore, based on the conservation law of mass and energy, to study iron and steel manufacturing process (ISMP), this paper, taking carbon price into consideration, establishes a muti-optimization model of energy consumption, CO2 emission and cost. After optimization with different objectives, the production cost per tonne of crude steel is reduced by 192.03 CNY (7.71%), the CO2 emission per tonne of crude steel is reduced by 224.22 kg (13.37%), and the energy consumption per tonne of steel is reduced by 51.20 kgce (9.10%). Moreover, based on the optimization results under different objectives, it is ironmaking process (coal ratio and ore ratio) and steelmaking process (amount of scrap steel) that has more impact on three above as well as ore blending and coal blending have a great influence on production cost but little effect on energy consumption and CO2 emission.


Assuntos
Dióxido de Carbono , Ferro , Aço/química , Carvão Mineral , Carbono
4.
Soil Secur ; 11: None, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37435407

RESUMO

Soil acidity is challenging agricultural production in Ethiopia. Above 43% of the farmland is under soil acidity problem and it leads to low crop yields and production losses. Ag-lime is widely considered as an effective remedy for amending soil acidity. This study assesses the current structure of ag-lime value chain and its functionality focusing on central parts of Ethiopia where lime is produced and channeled to acidity affected areas. The study uses Ethiopia as a case study and applies qualitative methods such as key informant interviews and focus group discussions to collect data from different actors in the ag-lime value chain. Key findings indicate that both public and private ag-lime producing factories are operating below their capacity. Due to limited enabling environments, the engagement of private sector in ag-lime value chain is minimal. In addition, farmers have a good awareness of soil acidity problem on their farms, and its causes and mitigation strategies in all regions. However, the adoption of ag-lime by smallholders was minimal. Overall, the current structure of the ag-lime value chain appears fragmented and needs improvement. Addressing soil acidity challenge through efficient ag-lime value chain could narrow lime supply-demand mismatches and increase widespread adoption by farmers to enhance crop productivity and food security in acidity-prone areas of the country.

5.
Bioresour Technol ; 374: 128802, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36858122

RESUMO

The aim of this review was to study why, despite large investments in research and development, algae biodiesel is still not price competitive with fossil fuels. Microalgal production was confirmed to be a critical cost item (84 up to 93 %) for biodiesel regardless of the production technology. Techno-economic assessment revealed the main cost drivers during mass cultivation. It is argued that a breakthrough in the cultivation efficiency of microalgae is identified as a necessary condition for achieving price-competitive microalgal biodiesel. The key bottlenecks were identified as follows: (1) light and O2 concentration management; (2) overnight respiratory loss of oil. It is concluded that most of the research on microalgae biodiesel yields economically over-optimistic presumptions because it has been based on laboratory scale experiments with a low level of interdisciplinary overlap.


Assuntos
Biocombustíveis , Microalgas , Tecnologia , Combustíveis Fósseis , Biomassa
6.
Plant Biotechnol J ; 21(6): 1254-1269, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36811226

RESUMO

Immune checkpoint inhibitors (ICIs) have achieved huge clinical success. However, many still have limited response rates, and are prohibitively costly. There is a need for effective and affordable ICIs, as well as local manufacturing capacity to improve accessibility, especially to low-to-middle income countries (LMICs). Here, we have successfully expressed three key ICIs (anti-PD-1 Nivolumab, anti-NKG2A Monalizumab, and anti-LAG-3 Relatimab) transiently in Nicotiana benthamiana and Nicotiana tabacum plants. The ICIs were expressed with a combination of different Fc regions and glycosylation profiles. They were characterized in terms of protein accumulation levels, target cell binding, binding to human neonatal Fc receptors (hFcRn), human complement component C1q (hC1q) and various Fcγ receptors, as well as protein recovery during purification at 100 mg- and kg-scale. It was found that all ICIs bound to the expected target cells. Furthermore, the recovery during purification, as well as Fcγ receptor binding, can be altered depending on the Fc region used and the glycosylation profiles. This opens the possibility of using these two parameters to fine-tune the ICIs for desired effector functions. A scenario-based production cost model was also generated based on two production scenarios in hypothetical high- and low-income countries. We have shown that the product accumulation and recovery of plant production platforms were as competitive as mammalian cell-based platforms. This highlights the potential of plants to deliver ICIs that are more affordable and accessible to a widespread market, including LMICs.


Assuntos
Neoplasias , Animais , Humanos , Inibidores de Checkpoint Imunológico , Receptores de IgG , Mamíferos
7.
Heliyon ; 9(1): e12902, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685476

RESUMO

This paper presents the technical, financial, and environmental impact assessment of a 50-MW (MW) utility-scale wind farm in Ghana at four locations: Anloga, Atiteti, Sege, and Denu. The monthly average wind speeds recorded at the locations were 6.01 m/s, 5.98 m/s, 5.46 m/s, and 5.17 m/s respectively at 60 m above ground level. Capacity factors of 24.9%, 24.4%, 20.6%, and 18.0% were obtained at the locations respectively. The Net Present Value (NPV) was the main financial metric employed to determine the viability of the projects. The results indicated that a potential utility-scale wind project is viable at all locations under study. Furthermore, the Electricity Exported to the Grid and the Electricity Export Rate (EER) had the highest impact of 0.63 and 0.62 on the NPV respectively and therefore these key parameters should be well considered before any potential project implementation.

8.
Vet Anim Sci ; 18: 100272, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36458153

RESUMO

A total of 14,200, day-old broiler chicks were allotted into two batches (B1=Winter and B2 = Summer) with 6 replicates each for 30 days, and 16,000, day-old Sonali chicks were allotted into 2 batches with 4 replicates each for 60 days to assess the growth performance, meat yield, and lipid profiles of the blood of chickens. Broiler chickens showed significantly higher body weight, feed intake, and lower FCR and production cost with a tendency to increase mortality compared with Sonali chickens. However, net profit tended to be higher in Sonali chickens compared to broiler chickens. The higher meat yield traits were observed in the broiler chicken compared with the Sonali chicken (p<0.001). Lipid profile did not differ (p>0.05) between chicken types. However, lipid profiles tended to be higher in broiler chicken than in Sonali chicken, except for the low-density lipoprotein (LDL). Growth performance, meat yield traits, and lipid profiles did not differ (p>0.05) between batches, except for the dressing percentage. Dressing (%) was higher in B1 than in B2 (p<0.05). No interaction between batch and chicken type was found in the growth performance, meat yield, and blood lipid profile of chickens. Therefore, broiler chickens performed better than Sonali chickens in terms of growth and meat yield traits. Nevertheless, Sonali chickens tended to perform better than broilers in terms of consumer preference, net profit, and lowering total cholesterol and triglyceride. However, more studies are needed to confirm the present findings and make the suggestion to use a suitable chicken type for meat production.

9.
Poult Sci ; 101(12): 102194, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36274436

RESUMO

For many producers, introduction of improved animal welfare systems is a turning point in their future production strategies as it increases production costs. The increase in egg retail prices is of growing concern not only for producers, but also for retailers and consumers. However, no report has calculated the estimated production costs or retail prices associated with introducing practices that support improved animal welfare in poultry farms in Japan. Therefore, this study aimed to estimate the production costs and table egg prices of 6 types of laying hen systems: conventional cage (CC): 8- and 12-tiers (CC8, CC12), enriched cage (EC): 8- and 12-tiers (EC8, EC12), aviary (AV), and barn systems (BR). Production costs include land purchases, construction costs of facilities, equipment and machinery, quantity of feed provided, farming materials invested, and wages. As a result, farm gate prices were estimated as CC8 = 12.19, CC12 = 12.19, EC8 = 14.52, EC12 = 14.52, AV = 21.14, and BR = 28.74 [yen/egg], and the production cost, including building the new farm, increased by EC8 = 19.1%, EC12 = 19.1%, AV = 73.4%, and BR = 135.7%, respectively, referring to the value of CC. The results show that the prices increase in systems between CC and BN. The retail price or table egg price was estimated to be CC8 = 24.68, CC12 = 24.68, EC8 = 28.07, EC12 = 28.07, AV = 37.27, and BR = 48.53 [yen/egg]. The retail price of BR is approximately twice that of CC. In addition, assuming that all of Japan's eggs were produced in the BR system, the soaring cost of eggs would likely affect the prices of factory eggs, such as liquid eggs and other products, thus affecting the prices of various food products. Understanding the significant management costs that affect the retail price of eggs would facilitate improved policies and practical approaches to support poultry farms and sustainable farming activities while addressing public concerns.


Assuntos
Criação de Animais Domésticos , Abrigo para Animais , Animais , Feminino , Criação de Animais Domésticos/métodos , Galinhas , Aves Domésticas , Japão , Óvulo
10.
Environ Sci Technol ; 56(12): 8571-8580, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35653301

RESUMO

CO2-enhanced oil recovery (EOR) can have less GHG emissions compared to conventional oil production methods. The economy of CO2-EOR can significantly benefit from the recent rise of carbon prices in carbon markets due to its greenhouse gas (GHG) emission savings. This study conducted a life cycle assessment (LCA) of CO2-EOR in major hydrocarbon provinces of the world. Estimated net GHG emissions of CO2-EOR were compared with GHG emissions of average produced oil in the given country. When sourcing CO2 from coal-fired power plants, Kazakhstan and China have net GHG emissions of CO2-EOR of 276 and 380 kg CO2 eq/bbl, respectively, which are lower than the GHG emission factor of average oil produced in each of them. Significantly lower GHG emissions of CO2-EOR are observed in other hydrocarbon provinces (Iraq, Saudi Arabia, Kuwait, etc.), where CO2 could be delivered from Natural Gas Combined Cycle (NGCC) power plants. However, the cost of CO2 capture is higher at NGCC power plants than at coal-fired power plants. Further, we developed a techno-economic assessment (TEA) model of the CO2-EOR and integrated it with LCA to thoroughly consider carbon credits in its economy. The model was built based upon previous investigations and used statistics from a large industrial data set of CO2-EOR to produce accurate estimates of the CO2-EOR economy. The technical model iteratively estimated the balance of three fluids (crude oil, CO2, and water) in the CO2-EOR system with a 25 year operational lifespan and obtained actual data for the LCA and TEA models. The model was simulated for the Kazakhstan case with its oil market conditions for a demonstration purpose. TEA results showed that, with the available low-cost CO2 capture source or high CO2 cost in carbon trading, CO2-EOR can compete with current upstream projects in Kazakhstan by simultaneously increasing oil production and reducing GHG emissions.


Assuntos
Dióxido de Carbono , Gases de Efeito Estufa , Animais , Carbono , Dióxido de Carbono/análise , Sequestro de Carbono , Carvão Mineral , Efeito Estufa , Estágios do Ciclo de Vida , Gás Natural
11.
J Anim Sci ; 100(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35714053

RESUMO

Precision feeding (PF) aims to provide the right amount of nutrients at the right time for each animal. Lactating sows generally receive the same diet, which either results in insufficient supply and body reserve mobilization, or excessive supply and high nutrient excretion. With the help of online measuring devices, computational methods, and smart feeders, we introduced the first PF decision support system (DSS) for lactating sows. Precision (PRE) and conventional (STD) feeding strategies were compared in commercial conditions. Every day each PRE sow received a tailored ration that had been computed by the DSS. This ration was obtained by blending a diet with a high AA and mineral content (13.00 g/kg SID Lys, 4.50 g/kg digestible P) and a diet low in AAs and minerals (6.50 g/kg SID Lys, 2.90 g/kg digestible P). All STD sows received a conventional diet (10.08 g/kg SID Lys, 3.78 g/kg digestible P). Before the trial, the DSS was fitted to farm performance for the prediction of piglet average daily gain (PADG) and sow daily feed intake (DFI), with data from 1,691 and 3,712 lactations, respectively. Sow and litter performance were analyzed for the effect of feeding strategy with ANOVA, with results considered statistically significant when P < 0.05. The experiment involved 239 PRE and 240 STD sows. DFI was similarly high in both treatments (PRE: 6.59, STD: 6.45 kg/d; P = 0.11). Litter growth was high (PRE: 2.96, STD: 3.06 kg/d), although it decreased slightly by about 3% in PRE compared to STD treatments (P < 0.05). Sow body weight loss was low, although it was slightly higher in PRE sows (7.7 vs. 2.1 kg, P < 0.001), which might be due to insufficient AA supply in some sows. Weaning to estrus interval (5.6 d) did not differ. In PRE sows SID Lys intake (PRE: 7.7, STD: 10.0 g/kg; P < 0.001) and digestible P intake (PRE: 3.2, STD: 3.8 g/kg; P < 0.001) declined by 23% and 14%, respectively, and feed cost decreased by 12%. For PRE sows, excretion of N and P decreased by 28% and 42%, respectively. According to these results, PF appears to be a very promising strategy for lactating sows.


In lactating sows, nutrient requirements among individual animals vary greatly. With a single diet, lactating sows are likely to be either underfed, which results in body reserve mobilization, or overfed, which results in nutrient excretion. Precision feeding (PF) is a new feeding strategy that aims to provide the right amount of nutrients at the right time for each animal. In this study, we focus on the implementation and the evaluation of a decision support system (DSS) that delivers daily tailored diets to lactating sows. Two experimental treatments were compared: a precision feeding strategy based on the DSS (PRE treatment; 239 sows), and a conventional feeding strategy (STD treatment; 240 sows). Digestible lysine intake and digestible phosphorus intake were reduced by 23% and 14% in PRE sows, respectively, and feed cost by 12%, compared to STD sows. Excretion of nitrogen and phosphorus also decreased for PRE sows by 28% and 42%, respectively. Sow body weight loss was low, although slightly higher in PRE sows, which might be due to insufficient amino acid supply in some sows. PF appears to be a very promising strategy for matching nutrient supply to the specific nutrient requirements of lactating sows.


Assuntos
Infecções Sexualmente Transmissíveis , Doenças dos Suínos , Animais , Feminino , Gravidez , Ração Animal/análise , Dieta/veterinária , Fazendas , Lactação , Lisina/metabolismo , Minerais/farmacologia , Paridade , Infecções Sexualmente Transmissíveis/veterinária , Suínos
12.
Sci Total Environ ; 837: 155742, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35526636

RESUMO

The objective of this techno-economic analysis is to define the costs for an industrial microalgae production process, comparing different operation strategies (Nannochloropsis oceanica cultivation during the whole year or cultivation of two species, where Phaeodactylum tricornutum and Tisochrysis lutea alternate), production scales (1 and 10 ha), harvesting technologies (centrifugation or ultrafiltration) and drying methods (freeze-drying or spray drying). This study is based on an industrial scale process established in the south of Portugal. The strategy of cultivating N. oceanica all year round is more attractive from an economic perspective, with production costs of 53.32 €/kg DW and a productivity of 27.61 t/y for a scale of 1 ha, a 49.31% lower cost and two-fold productivity than species alternation culture strategy. These results are for biomass harvested by centrifugation (10.65% biomass cost) and freeze-drying (20.15% biomass cost). These costs could be reduced by 7.03% using a combination of ultrafiltration and spray drying, up to 17.99% if expanded to 10 ha and 10.92% if fertilisers were used instead of commercial nutrient solutions. The study shows potentially competitive costs for functional foods, food, and feed additives, specialised aquaculture products (live feed enrichment) and other high value applications (e.g., cosmetics).


Assuntos
Cosméticos , Haptófitas , Microalgas , Aquicultura , Biomassa , Alimentos
13.
Vet World ; 15(3): 551-557, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35497946

RESUMO

Background and Aim: The potential solution is to use agro-industrial by-products as an unconventional source of raw materials for broiler feed. This study aims to determine the effects of substituting prickly pear (FB; Opuntia ficus-indica) husks for corn and FB seed cake for soybean meal on the production performance, slaughter characteristics, and chemical composition of broiler meat. Materials and Methods: Two hundred day-old chicks of equal sex ratio (1:1) of Big Fast strain, weighing on average 37±2g, were randomly divided into four homogeneous groups of 50 subjects each. Each group was subdivided into 10 packs of five animals, which were banded and numbered. Rations with substitution rates of 0%, 10%, 20%, and 30% of corn and soybean meal by dehydrated husks and FB cake were randomly distributed among the groups. Results: Average daily gains and body weights on 48 days were improved (p<0.05) in 10% and 20% groups, while the 30% group performed identically to the control. Cold carcass yield was optimal in 10% and 20% groups. The liver weight of the experimental groups decreased significantly (p<0.05), while their gizzard weight increased significantly (+24 points). The meat protein rate evolved proportionally to the substitution rate, whereas the fat rate depreciated by up to -1.08 points for the 30% group compared to the control. Conclusion: Incorporating FB processing by-products into broiler feed at rates of 10% and 20% improves zootechnical performance, carcass yields, and the chemical composition of the meat.

14.
Environ Sci Pollut Res Int ; 29(45): 69022-69036, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35554833

RESUMO

Backfilling mining is a green mining method. The rational design of the compressed ratio of the backfilling body can reduce backfilling mining costs while avoiding mining-induced environmental damage. At present, the enumeration method is a common design method for the compressed ratio of the backfilling body of backfilling mining under buildings (structures). However, the design method has some problems, such as cumbersome processes and time consumption. Therefore, this paper proposes an intelligent optimization design method of the compressed ratio of backfilling body and constructs the design flow of the method. The method takes economic benefits as the optimization goal and takes the mining-induced subsidence of protected objects to meet their fortification requirements as the constraint condition. Within the feasible region of the compressed ratio, the intelligent optimization algorithm is used to search for the minimum compressed ratio that satisfies the constraints. This paper used the method to design the compressed ratio of the backfilling panel in the Dongtan Coal Mine. The research results show that the method can quickly design the optimal compressed ratio compared with the enumeration method and cut the production cost on the premise of the safety of ground buildings (structures).


Assuntos
Minas de Carvão , Carvão Mineral , Minas de Carvão/métodos , Pressão
15.
Heliyon ; 8(4): e09216, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35399389

RESUMO

This work investigated the influence of process variables of extraction temperature (35-55 °C), solid to liquid ratio (1:20-1:50 g/mL) and time (100-200 min) on the total phenolic content (TPC) and yield (EY) of Carica papaya leaves (CPL) extracts using Box-Behnken experimental design available in Design Expert software. Bi-objective process optimization was also carried out using the desirability function algorithm. The optimum process variables were later used to design an integrated process for the production of CPL extracts with the assistance of SuperPro Designer software. Scale-up studies and economic analysis for CPL extracts production were investigated in the range of 0.638-20.431 × 103 kg CPL extracts/y to determine the most economically feasible production capacity based on the minimum unit production cost (UPC) of CPL extracts. The risk and sensitivity analyses of the most economically feasible production scale were carried out using the Monte Carlo simulation in Oracle Crystal Ball software. Process variables had notable influences on the TPC and EY of CPL extracts. The extraction temperature of 35 °C, solid to liquid ratio of 40.25 g/mL and time of 100 min gave the optimum TPC of 74.65 mg GAE/g d.b and EY of 18.76 % (w/w). HPLC results indicated that CPL extracts were rich in gallic, betulinic, chlorogenic, ellagic, ferulic and caffeic acids. The designed integrated process showed similar behavior with the laboratory scale of 0.18758 g CPL extracts/batch. The preliminary techno-economic analysis indicated that plant capacity has a strong dependence on the material & energy demands and process economics. Plant capacity of 19.857 × 103 kg CPL extracts/y possessed the least UPC and was selected as the most economically feasible scale. The certainty of obtaining base case UPC value of 525.21 US$/kg CPL extracts was 75.20%. Sensitivity analysis showed that extracts recovery, CPL/water, centrifuge purchase cost, extraction time, extractor purchase cost and extraction temperature contributed -5.3 %, +42.8%, +4.0%, +47.1%, +0.1%, and +0.5%, respectively to the variance in UPC of CPL extracts.

16.
Adv Biochem Eng Biotechnol ; 181: 181-193, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35246696

RESUMO

There are numerous biosurfactant producing strains and products reported annually most of which aspiring to potential future industrial and environmental applications. Only a few of these compounds have reached commercial applications due to many impediments to large-scale production and applications. We investigate some of the important criteria and investigations required to achieve such future commercial application.


Assuntos
Tensoativos
17.
J Econ Entomol ; 115(2): 455-461, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35089346

RESUMO

A newly discovered entomopathogenic fungus Cordyceps javanica (Friedrichs & Bally) Samson & Hywel-Jones (Hypocreales: Cordycipitaceae) strain Wf GA17 was compared with the commercial Cordyceps fumosorosea Wize (Hypocreales: Cordycipitaceae) Apopka 97 strain for liquid-culture production, formulation, insecticidal efficacy, and storage stability under laboratory conditions. We compared culture media with carbon:nitrogen (C:N) ratios of 10:1, 30:1, and 50:1 for these two isolates. A third strain, C. fumosorosea strain ARSEF 3581, had previously been optimized for liquid-culture production of blastospores at 10:1 C:N served as an added control. These seven cultures were processed by spray drying with skim milk powder, stored at 25oC to evaluate storage stability, and assayed for insecticidal activity against Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) neonates. Final blastospore concentrations were not significantly different among cultures, ranging from 4.47 to 9.88 × 108 spores/ml. Fungal biomass decreased and final glucose concentrations increased with increasing C:N ratios, indicating better fungal growth with higher nitrogen concentrations. Product yields from the spray dryer (grams per liter culture) increased with increased C:N ratios while spore concentrations decreased, ranging from 2.27 to 7.17 × 109 spores/g. There were no significant differences for insecticidal efficacy among the seven treatments. Spores produced in 10:1 C:N ratio media retained viability longer than spores produced in other media. Cost of ingredients decreased with increasing C:N ratios, such that the 30:1 media may yield the most economical product. The raw material cost needed for application was 1.4× greater for Wf GA17 compared with Apopka 97, a difference that could be erased by optimization of culture conditions.


Assuntos
Cordyceps , Hypocreales , Inseticidas , Animais , Meios de Cultura , Nitrogênio , Controle Biológico de Vetores , Esporos Fúngicos
18.
Prev Vet Med ; 195: 105470, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34461467

RESUMO

Small-scale farming of meat chicken flocks using local native breeds contributes to the economy of many rural livelihoods in Vietnam and many other low- and middle-income countries (LMICs). These systems are also the target of high levels of antimicrobial use (AMU); however, little is known about the profitability and sustainability of such systems. Since small-scale farms are commercial enterprises, this knowledge is essential to develop successful strategies to curb excessive AMU. Using longitudinal data from 203 small-scale (100-2,000 heads) native chicken flocks raised in 102 randomly selected farms in Dong Thap province (Mekong Delta, Vietnam), we investigated the financial and economic parameters of such systems and the main constraints to their sustainability. Feed accounted for the largest financial cost (flock median 49.5 % [Inter-quartile range (IQR) 41.5-61.8 %]) of total costs, followed by day-old-chicks (DOCs) (median 30.3 % [IQR 23.2-38.4 %]), non-antimicrobial health-supporting products (median 7.1 % [IQR 4.7-10.5 %]), vaccines (median 3.1 % [IQR 2.2-4.8 %]), equipment (median 1.9 % [IQR 0.0-4.9 %]) and antimicrobials (median 1.9 % [IQR 0.7-3.6 %]). Excluding labor costs, farmers achieved a positive return on investment (ROI) from 120 (59.1 %) flocks, the remainder generating a loss (median ROI 124 % [IQR 36-206 %]). Higher ROI was associated with higher flock size and low mortality. There was no statistical association between use of medicated feed and flock mortality or chicken bodyweight. The median daily income per person dedicated to raising chickens was 202,100 VND, lower than alternative rural labor activities in the Mekong Delta. In a large proportion of farms (33.4 %), farmers decided to stop raising chickens after completing one cycle. Farmers who dropped off chicken production purchased more expensive feed (in 1000 VND per kg): 11.1 [10.6-11.5] vs. 10.8 [10.4-11.3] for farms that continued production (p = 0.039), and experienced higher chicken mortality (28.5 % [12.0-79.0 %] vs. 16 [7.5-33.0 %]; p = 0.004). The rapid turnover of farmers raising chickens in such systems represents a challenge to the uptake of messages on appropriate AMU and chicken health. To ensure sustainability of small-scale commercial systems, advisory services need to be available to farmers as they initiate new flocks, and support them in the early stages to help overcome their limited experience and skills. This targeted approach would support profitability whilst reducing risk of emergence of AMR and infectious disease from these systems.


Assuntos
Criação de Animais Domésticos , Anti-Infecciosos , Galinhas , Criação de Animais Domésticos/economia , Animais , Fazendeiros , Fazendas , Humanos , Vietnã
19.
Front Plant Sci ; 12: 615853, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747000

RESUMO

Indoor growing systems with light-emitting diodes offer advantages for the growth of tomato seedlings through uniform and optimized environmental conditions which increase consistency between plants and growing cycles. CO2 enrichment has been shown to improve the yield of crops. Thus, this research aimed to characterize the effects of varied light intensities and CO2 enrichment on the growth, morphology, and production efficiency of tomato seedlings in indoor growing systems. Four tomato cultivars, "Florida-47 R," "Rebelski," "Maxifort," and "Shin Cheong Gang," were subjected to three different daily light integrals (DLIs) of 6.5, 9.7, and 13 mol m-2 d-1 with a percent photon flux ratio of 40 blue:60 red and an end-of-day far-red treatment of 5 mmol m-2 d-1. The plants were also subjected to three different CO2 concentrations: 448 ± 32 (400-ambient), 1010 ± 45 (1000), and 1568 ± 129 (1600) µmol mol-1. Temperature was maintained at 24.3°C ± 0.48/16.8°C ± 1.1 (day/dark; 22.4°C average) and relative humidity at 52.56 ± 8.2%. Plant density was 1000 plants m-2 until canopy closure. Morphological measurements were conducted daily to observe the growth response over time. In addition, data was collected to quantify the effects of each treatment. The results showed increases in growth rate with increases in the DLI and CO2 concentration. In addition, CO2 enrichment to 1000-1600 µmol mol-1 increased the light use efficiency (gDM mol-1 applied) by 38-44%, and CO2 enrichment to 1600 µmol mol-1 did not result in any additional increase on shoot fresh mass, shoot dry mass, and stem extension. However, the net photosynthetic rate obtained with 1600 µmol mol-1 was 31 and 68% higher than those obtained with 1000 and 400 µmol mol-1, respectively. Furthermore, the comparison of the light and CO2 treatment combinations with the control (13 mol m-2 d-1-400CO2) revealed that the plants subjected to 6.5DLI-1600CO2, 9.7DLI-1000CO2, and 9.7DLI-1600CO2 treatment combinations exhibited the same growth rate as the control plants but with 25-50% less DLI. Furthermore, two treatment combinations (13.0DLI-1000CO2 and 13.0DLI-1600CO2) were associated with the consumption of comparable amount of energy but increased plant growth by 24-33%.

20.
Environ Sci Pollut Res Int ; 28(34): 46781-46796, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33634400

RESUMO

Agriculture is facing many challenges as climate change, drought, and salinity which call for urgent interventions to fast adaptation and diversification such as the introduction of new climate smart and stress tolerant crops such as quinoa. This study aims to introduce new high yielding quinoa cultivars conducted under several agronomic practices (rainfed, irrigation, and organic amendment) and to assess the technical and economic aspects related to quinoa seed production, transformation, and quality. Results obtained from agronomic trials clearly showed that International Center for Biosaline Agriculture cultivars recorded higher yields than locally cultivated seeds. Irrigation and organic amendment had a tremendous effect on quinoa productivity as it increased most of cultivar's yield by more than three times compared with rainfed conditions. Production cost analysis showed that using mechanized production and processing practices combined with irrigation and organic amendment can reduce seed production and processing cost from 2.8 to 1.2 USD kg-1 compared with manual production system under rainfed conditions. The diagnosis of the quinoa transformation pathways revealed different transformation levels, and the production cost increased with the level of transformation due to high cost of labor and raw material. Analysis of quinoa seeds showed that macronutrient content is mostly not affected by pearling process, while micronutrients content was significantly decreased in processed seeds. In addition, total saponin content was reduced to an acceptable level after using mechanical pearling compared with manual abrasion.


Assuntos
Chenopodium quinoa , Secas , Marrocos , Salinidade , Sementes
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