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1.
J Environ Manage ; 358: 120917, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38663084

RESUMO

Permafrost regions play an important role in global carbon and nitrogen cycling, storing enormous amounts of organic carbon and preserving a delicate balance of nutrient dynamics. However, the increasing frequency and severity of wildfires in these regions pose significant challenges to the stability of these ecosystems. This review examines the effects of fire on chemical, biological, and physical properties of permafrost regions. The physical, chemical, and pedological properties of frozen soil are impacted by fires, leading to changes in soil structure, porosity, and hydrological functioning. The combustion of organic matter during fires releases carbon and nitrogen, contributing to greenhouse gas emissions and nutrient loss. Understanding the interactions between fire severity, ecosystem processes, and the implications for permafrost regions is crucial for predicting the impacts of wildfires and developing effective strategies for ecosystem protection and agricultural productivity in frozen soils. By synthesizing available knowledge and research findings, this review enhances our understanding of fire severity's implications for permafrost ecosystems and offers insights into effective fire management strategies.


Assuntos
Ecossistema , Pergelissolo , Solo , Incêndios Florestais , Solo/química , Incêndios , Nitrogênio/análise , Carbono/análise
2.
PLoS Comput Biol ; 17(9): e1009255, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34570767

RESUMO

Approximately 85% of tuberculosis (TB) related deaths occur in low- and middle-income countries where health resources are scarce. Effective priority setting is required to maximise the impact of limited budgets. The Optima TB tool has been developed to support analytical capacity and inform evidence-based priority setting processes for TB health benefits package design. This paper outlines the Optima TB framework and how it was applied in Belarus, an upper-middle income country in Eastern Europe with a relatively high burden of TB. Optima TB is a population-based disease transmission model, with programmatic cost functions and an optimisation algorithm. Modelled populations include age-differentiated general populations and higher-risk populations such as people living with HIV. Populations and prospective interventions are defined in consultation with local stakeholders. In partnership with the latter, demographic, epidemiological, programmatic, as well as cost and spending data for these populations and interventions are then collated. An optimisation analysis of TB spending was conducted in Belarus, using program objectives and constraints defined in collaboration with local stakeholders, which included experts, decision makers, funders and organisations involved in service delivery, support and technical assistance. These analyses show that it is possible to improve health impact by redistributing current TB spending in Belarus. Specifically, shifting funding from inpatient- to outpatient-focused care models, and from mass screening to active case finding strategies, could reduce TB prevalence and mortality by up to 45% and 50%, respectively, by 2035. In addition, an optimised allocation of TB spending could lead to a reduction in drug-resistant TB infections by 40% over this period. This would support progress towards national TB targets without additional financial resources. The case study in Belarus demonstrates how reallocations of spending across existing and new interventions could have a substantial impact on TB outcomes. This highlights the potential for Optima TB and similar modelling tools to support evidence-based priority setting.


Assuntos
Alocação de Recursos/economia , Software , Tuberculose/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Criança , Pré-Escolar , Biologia Computacional , Análise Custo-Benefício , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Modelos Econômicos , Prevalência , Estudos Prospectivos , República de Belarus/epidemiologia , Tuberculose/epidemiologia , Tuberculose/transmissão , Adulto Jovem
3.
Trop Anim Health Prod ; 54(5): 285, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076096

RESUMO

This study was carried out to find the environmental factors which have a significant effect on the productive and reproductive characteristics of the Balochi sheep. The study used data from 729 ewes and 71 rams for a period of 13 years (2003 to 2016) at the Sheep Research Center, Yet Abad, Balochistan, Pakistan. The productive characteristics considered for current study were weight, birth weight (BW), 90 days weight (3 MW), 180 days weight (6 MW), 270 days weight (9 MW), 365 days (12 MW), and 2 years weight (24 MW). Reproductive characteristics measured were ewe age at first service (AFS), service period (SP) of ewe, age at 1st lambing (AFL) of ewe, lambing interval (LI), and sex ratio. Restricted maximum likelihood (REML) assessments of different characteristics were analyzed for the Balochi sheep on the basis of location, birth year (YOB), season of birth (SOB), type of birth (TOB), and sex of lamb. The average means ± SE for BW, WW, 6 MW, 9 MW, 12 MW, and 24 MW, were 3.28 ± 0.83, 17.20 ± 2.04, 21.94 ± 1.60, 26.20 ± 2.87, 30.21 ± 3.58, and 37.11 ± 2.84 for ram and 2.56 ± 0.53, 15.69 ± 1.45, 19.57 ± 1.77, 24.07 ± 2.70, 27.46 ± 2.09, and 34.61 ± 2.32 for ewes respectively. The results of reproductive performance of the Balochi sheep age of ewe at the time of breeding, age at first service (AFS), service period (SP), age at first lambing (AFL), and lambing interval (LI) were 1078 ± 2.2, 579.61 ± 0.6, 206.25 ± 0.2, 731.67 ± 0.3, and 256.60 ± 0.3 days respectively. The twining and lambing rates were 10.12% and 86.78%, while the sex proportion for ram and ewes was 50.12:49.37. Area, sex, and TOB had a significant (p < 0.05) effect on weight while TOB (twinning rate) was higher in Balochi sheep. These conditions affected the productive and reproductive performance of the Balochi sheep. At Sheep Research Center, Yet Abad, Balochistan, Pakistan, performed fundamentally better in all qualities such as weight gain and reproductive performance. Supplements were given with feed to get maximum profit from the sheep of Yet Abad farm. The birth weight of males was higher than that of females and single conceived Balochi sheep were heavier than that of twins. Thus, it was concluded that the Balochi sheep can be improved with better management practices, feeding, and disease control.


Assuntos
Reprodução , Carneiro Doméstico , Animais , Peso ao Nascer , Feminino , Masculino , Parto , Gravidez , Estações do Ano , Ovinos
4.
Ecotoxicol Environ Saf ; 208: 111582, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396105

RESUMO

In recent years, heavy metal pollution has caused immeasurable harm to the environment. As an emerging technology, phytoremediation technology has gained a place in the treatment of heavy metal pollution with its unique advantages. This study analyzes the toxic effects of mulberry (Morus alba) seeds, seedling growth and silkworm under heavy metal stress of lead (Pb) and cadmium (Cd), and explore the accumulation and migration of Pb and Cd in the soil-mulberry tree-silkworm system. The main results were as follows: (1) Seed germination and potted seedling experiments were conducted under heavy metal Pb and Cd stresses, and it was found that Pb and Cd had inhibitory effects on mulberry seed germination, growth and photosynthesis of mulberry seedlings, and as the concentration of heavy metals increased, the stronger the inhibitory effect. Moreover, Pb and Cd have a synergistic effect under compound stress. (2) The accumulation and transfer rules of Pb and Cd ions in mulberry were different. The content of Pb in mulberry was root > leaf > stem and the content of Cd was root > stem > leaf. The combined stress promoted the transfer of Pb and Cd from the underground part to the aerial portion of mulberry. (3) The silkworm feeds on mulberry leaves contaminated with heavy metals in this experiment and found that: with the increase of silkworm feeding, the heavy metal content in the silkworm body increased significantly, but the content remained in the silkworm body was less, most of it was excreted with silkworm excrement. Combined stress has no significant effect on the detoxification mechanism of silkworm. It is indispensable to think of the synergistic effect of heavy metals on plants germination when seeds are used for phytoremediation.


Assuntos
Bombyx/fisiologia , Cádmio/toxicidade , Cadeia Alimentar , Chumbo/toxicidade , Morus/fisiologia , Poluentes do Solo/toxicidade , Solo/química , Animais , Biodegradação Ambiental , Cádmio/análise , Cádmio/metabolismo , Frutas/química , Metais Pesados/análise , Fotossíntese , Folhas de Planta/química , Plântula/química , Poluentes do Solo/análise , Poluentes do Solo/metabolismo
5.
Crit Rev Eukaryot Gene Expr ; 27(4): 331-340, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29283327

RESUMO

Dengue is an acute infectious disease of viral etiology characterized by lymphadenopathy, leucopenia, headache, biphasic fever, pain in various parts of the body, rashes, and extreme physical weakness. It is a vector-borne disease caused by a positive-stranded RNA virus of the family Flaviviridae, genus Flavivirus. Dengue inflicts a significant health, economic, and social burden on populations of endemic areas. Dengue virus is transmitted to humans by the mosquito vector Aedes aegypti. Vaccines against dengue viruses have been claimed to be developed, but as yet no effective treatment is available. Alternative therapeutic strategies to overcome this disease and its spread are direly needed. A traditional sterile insect technique (SIT) harms the health of male insects, leading to their reduced ability to compete for wild-type female insects for breeding. Oxitec (Abingdon, UK) has developed genetically modified (GM) strains of A. aegypti via the release of insects carrying a dominant lethal (RIDL) strategy. RIDL male mosquitoes offer a resolution to many of the limitations of traditional SIT, which has resulted in reduced application of SIT in mosquitoes. The technique using RIDL mosquitoes is considered to be ecologically friendly and specific. Homing endonuclease genes, also called selfish genes, can also be used in genetic modification methods in such a way that the vector population and its competency can be reduced. GM mosquitoes carrying a gene that transcribes RNA interference can also be crucial to control expression of RNA viruses. The RNA virus interference pathway is one of the most critical components of the innate immune system of insects that can frustrate a variety of RNA viruses such as Flaviviruses. Here, we summarize and focus on alternative techniques used to control dengue spread.


Assuntos
Aedes/genética , Animais Geneticamente Modificados/genética , Dengue/genética , Animais , Dengue/virologia , Humanos , Mosquitos Vetores/genética , Interferência de RNA/fisiologia , Vírus de RNA/genética
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