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1.
J Environ Manage ; 359: 120864, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38714029

RESUMEN

Deforestation rates in the Amazon have markedly increased in the last few years, affecting non-protected and protected areas (PAs). Brazil is a hotspot of Protected Area Downgrading, Downsizing, and Degazettement (PADDD) events, with most events associated with infrastructure projects. Despite the threats dams impose on PAs, there is a knowledge gap in assessing deforestation in PAs around large dams in the Amazon. This study investigates how deforestation affects Biodiversity Protection Areas (BioPAs) and Indigenous Lands around the Jirau and Santo Antônio (JSA) dams (Madeira River, Rondônia) and Belo Monte dam (Xingu River, Pará) in the Brazilian Amazon. We compared clear-cutting between PAs and control areas and the annual rates of forest change between pre-dam and post-dam periods. We discussed deforestation-related factors (e.g., PADDD events and the presence of management plans or councils). Our results show an increase in deforestation after the operation of the dams when environmental control from licensing agencies decreases and other political and economic factors are in practice. Indigenous Lands experienced a significant increase in deforestation around the Belo Monte dam, which is associated with the demarcation process and land conflicts. Surrounding the JSA dams, sustainable use BioPAs showed high deforestation rates, and 27 PADDD events were reported, four directly related to dams. In addition to dams, deforestation was associated with the crisis of Brazilian democracy and the weakening of environmental policies. In conclusion, the weak environmental control from environmental licensing agencies during dam operation and PADDD events have contributed to increased deforestation rates and additional stresses in the Amazon.

2.
Environ Sci Technol ; 58(19): 8349-8359, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38696360

RESUMEN

Agricultural ponds are a significant source of greenhouse gases, contributing to the ongoing challenge of anthropogenic climate change. Nations are encouraged to account for these emissions in their national greenhouse gas inventory reports. We present a remote sensing approach using open-access satellite imagery to estimate total methane emissions from agricultural ponds that account for (1) monthly fluctuations in the surface area of individual ponds, (2) rates of historical accumulation of agricultural ponds, and (3) the temperature dependence of methane emissions. As a case study, we used this method to inform the 2024 National Greenhouse Gas Inventory reports submitted by the Australian government, in compliance with the Paris Agreement. Total annual methane emissions increased by 58% from 1990 (26 kilotons CH4 year-1) to 2022 (41 kilotons CH4 year-1). This increase is linked to the water surface of agricultural ponds growing by 51% between 1990 (115 kilo hectares; 1,150 km2) and 2022 (173 kilo hectares; 1,730 km2). In Australia, 16,000 new agricultural ponds are built annually, expanding methane-emitting water surfaces by 1,230 ha yearly (12.3 km2 year-1). On average, the methane flux of agricultural ponds in Australia is 0.238 t CH4 ha-1 year-1. These results offer policymakers insights into developing targeted mitigation strategies to curb these specific forms of anthropogenic emissions. For instance, financial incentives, such as carbon or biodiversity credits, can mobilize widespread investments toward reducing greenhouse gas emissions and enhancing the ecological and environmental values of agricultural ponds. Our data and modeling tools are available on a free cloud-based platform for other countries to adopt this approach.


Asunto(s)
Agricultura , Gases de Efecto Invernadero , Metano , Estanques , Metano/análisis , Gases de Efecto Invernadero/análisis , Australia , Monitoreo del Ambiente , Cambio Climático
3.
Sci Total Environ ; 928: 172437, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38614343

RESUMEN

Tailings storage facilities (TSFs) represent an anthropogenic source of pollution, resulting in potential risks to both environmental integrity and human health. To date, the environmental and human health risks from TSFs in China have been under-researched. This study attempts to address this gap by developing, and geo-statistically analyzing two comprehensive databases. The first database (I) focuses on failed TSFs; we supply the statistics of environmental damages from 143 TSF failure incidents. Notably, approximately 75 % of the failure incidents involved tailings flows released into water bodies, resulting in a significant exacerbation of environmental pollution. To better inform ecological and human health risks, we present another database (II) for 147 non-failed TSFs to investigate the soil heavy metal contamination, considering 8 heavy metals. The findings reveal that (i) Cd, Pb, and Hg are the prominent pollutants across the non-failed TSF sites in China; (ii) lead­zinc and tungsten mine tailings storage sites exhibit the most severe pollution; (iii) Pb, Cd, and Ni present noteworthy non-carcinogenic risks to human health; (iv) >85 % of TSF sites pose carcinogenic risks associated with arsenic; and (v) health risks resulting from dermal absorption surpass ingestion for the majority of heavy metals, with the exception of Pb, where ingestion presents a more pronounced route of exposure. Our study presents a comprehensive evaluation of environmental and human health risks due to TSFs, highlighting the necessity for risk assessment of >14,000 existing TSFs in China.


Asunto(s)
Contaminación Ambiental , Metales Pesados , China , Humanos , Metales Pesados/análisis , Medición de Riesgo , Contaminación Ambiental/estadística & datos numéricos , Minería , Monitoreo del Ambiente , Contaminantes del Suelo/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos
4.
Food Chem ; 449: 139235, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38583405

RESUMEN

Acidic electrolyzed oxidizing water (AEOW) was applied to suppress disease development and maintain good quality of fresh fruit. However, the involvement of AEOW in improving disease resistance of fresh longan remains unknown. Here, transcriptomic and metabolic analyses were performed to compare non-treated and AEOW-treated longan during storage. The transcriptome analysis showed AEOW-induced genes associated with phenylpropanoid and flavonoid biosynthesis. The metabolome analysis found the contents of coumarin, phenolic acid, and tannin maintained higher levels in AEOW-treated longan than non-treated longan. Moreover, the weighted correlation network analysis (WGCNA) was performed to identify hub genes, and a gene-metabolite correlation network associated with AEOW-improved disease resistance in longan was constructed by the co-analysis of transcriptomics and metabolomics. These findings identified a series of important genes and metabolites involving in AEOW-induced disease resistance of longan fruit, expanding our knowledges on fruit disease resistance and quality maintenance at the transcript and metabolic levels.


Asunto(s)
Frutas , Metaboloma , Transcriptoma , Agua , Frutas/química , Frutas/metabolismo , Frutas/genética , Agua/metabolismo , Agua/análisis , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Electrólisis , Regulación de la Expresión Génica de las Plantas , Oxidación-Reducción , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
BMC Plant Biol ; 24(1): 203, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509491

RESUMEN

BACKGROUND: Quinoa leaves demonstrate a diverse array of colors, offering a potential enhancement to landscape aesthetics and the development of leisure-oriented sightseeing agriculture in semi-arid regions. This study utilized integrated transcriptomic and metabolomic analyses to investigate the mechanisms underlying anthocyanin synthesis in both emerald green and pink quinoa leaves. RESULTS: Integrated transcriptomic and metabolomic analyses indicated that both flavonoid biosynthesis pathway (ko00941) and anthocyanin biosynthesis pathway (ko00942) were significantly associated with anthocyanin biosynthesis. Differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were analyzed between the two germplasms during different developmental periods. Ten DEGs were verified using qRT-PCR, and the results were consistent with those of the transcriptomic sequencing. The elevated expression of phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), 4-coumarate CoA ligase (4CL) and Hydroxycinnamoyltransferase (HCT), as well as the reduced expression of flavanone 3-hydroxylase (F3H) and Flavonol synthase (FLS), likely cause pink leaf formation. In addition, bHLH14, WRKY46, and TGA indirectly affected the activities of CHS and 4CL, collectively regulating the levels of cyanidin 3-O-(3'', 6''-O-dimalonyl) glucoside and naringenin. The diminished expression of PAL, 4CL, and HCT decreased the formation of cyanidin-3-O-(6"-O-malonyl-2"-O-glucuronyl) glucoside, leading to the emergence of emerald green leaves. Moreover, the lowered expression of TGA and WRKY46 indirectly regulated 4CL activity, serving as another important factor in maintaining the emerald green hue in leaves N1, N2, and N3. CONCLUSION: These findings establish a foundation for elucidating the molecular regulatory mechanisms governing anthocyanin biosynthesis in quinoa leaves, and also provide some theoretical basis for the development of leisure and sightseeing agriculture.


Asunto(s)
Antocianinas , Chenopodium quinoa , Antocianinas/metabolismo , Chenopodium quinoa/genética , Chenopodium quinoa/metabolismo , Perfilación de la Expresión Génica/métodos , Transcriptoma , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Glucósidos , Regulación de la Expresión Génica de las Plantas
6.
J Comp Physiol B ; 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38453727

RESUMEN

Total dissolved gas supersaturation (TDGS) occurs when air mixes with water under pressure, which can be caused by features such as hydroelectric dams and waterfalls. Total dissolved gas supersaturation can cause harmful bubbles to grow in the tissues of aquatic animals, a condition known as gas bubble trauma (GBT). As gills are the primary gas exchange surface for most fish, it is through the gills that elevated total dissolved gases enter the blood and tissues of a fish. We describe the role of the gills in admitting TDGS into the body and discuss potential effects of bubbles in the gills on blood oxygen and carbon dioxide diffusion, blood ion and pH homeostasis, and nitrogenous waste excretion, as well as downstream effects on aerobic swimming performance.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38397646

RESUMEN

Within the 2030 Sustainable Development Agenda, large hydropower dams are positioned as a sustainable energy source, notwithstanding their adverse impacts on societies and ecosystems. This study contributed to ongoing discussions about the persistence of critical social issues, even after the investments of large amounts of resources in areas impacted by the construction of large hydropower dams. Our study focused on food insecurity and evaluated this issue in the city of Altamira in the Brazilian Amazon, which has been profoundly socially and economically impacted by the construction, between 2011 and 2015, of Brazil's second-largest dam, namely, Belo Monte. A survey in Altamira city featured a 500-household random sample. Structural equation modeling showed conditioning factors of 60% of the population experiencing varying food insecurity degrees. Poverty, female-led households, lower education, youth, and unemployment were strongly linked to higher food insecurity. Crowded, officially impacted, and resettled households also faced heightened food insecurity. Our findings underscore the food insecurity conditions in the region impacted by the Belo Monte dam, emphasizing the need to take into account this crucial issue while planning and implementing hydropower dams.


Asunto(s)
Ecosistema , Pobreza , Adolescente , Humanos , Femenino , Brasil , Ciudades , Inseguridad Alimentaria , Abastecimiento de Alimentos
8.
J Anim Sci ; 1022024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38198718

RESUMEN

Primiparous Angus × Simmental dams (n = 22) with an average body weight (BW) of 449 ±â€…32 kg of BW were divided based on two nutritional treatments: control (CTRL) and rumen-protected methionine (RPM). The control group received bermudagrass hay, corn gluten, and soybean hulls pellets supplementation (base diet); whereas the RPM group received the base diet in addition to 0.07% of DM of RPM at a fixed rate during the last trimester of gestation and the first ~80 d of lactation, in which calves (n = 17) were early weaned. Only male calves were included in this study. After weaning, calves born to RPM dams also received RPM from weaning (day 1) to day 100. Blood sampling and skeletal muscle biopsies for subsequent quantitative polymerase chain reaction (PCR) analysis were conducted on days 1, 25, 50, and 100 on calves. Quantitative PCR data were analyzed using GLIMMIX, and blood metabolites concentrations, BW, and body condition score (BCS) were analyzed using the MIXED procedure of SAS. There was no difference in maternal BW and BCS between treatments. Glucose and blood metabolites that served as biomarkers for liver health (e.g., aspartate transaminase, albumin, alkaline phosphatase, and alanine transaminase) were in the normal levels for all calves (P > 0.40). Calves in the RPM group had a greater expression of adipogenic genes (e.g., PPARG, LPL, and CEBPD) at day 100 compared with CTRL (P < 0.01). In addition, DNA methylation (DNMT1) and oxidative stress-related genes (SOD2 and NOS3) in the RPM group were upregulated at day 100 compared with CTRL (P < 0.01). These results may suggest that calves born to primiparous dams exposed to RPM supplementation are more prone to develop greater adipose tissue than CTRL calves. Furthermore, RPM supplementation may improve methylation processes, as shown by the upregulation of DNMT1. The results shown in our study aim at expanding the knowledge on fetal programming and early-life growth and development of beef cattle under supplementation with RPM.


Plane of nutrition plays a critical role in fetal and postnatal growth in beef cattle offspring. Methionine, a limiting amino acid in ruminants, is also involved in DNA methylation due to its role as S-adenosyl methionine precursor. A complete randomized design experiment was conducted to assess the fetal programming effect of rumen-protected methionine (RPM) supplementation on beef cattle. Calves born to primiparous beef heifers, that individually received RPM during the last trimester of gestation and lactation, had a greater expression of genes related to adipose tissue development, oxidative stress, and DNA methylation compared with those born to dams that did not receive rumen-protected supplementation. No difference in animal performance or blood parameters that serve as biomarkers for liver health status was detected. Our results suggest that maternal supplementation with RPM during the last trimester of gestation and lactation, and supplementation to the offspring after early weaning, could potentially increase adipose tissue development on male calves.


Asunto(s)
Suplementos Dietéticos , Metionina , Femenino , Animales , Bovinos , Masculino , Metionina/farmacología , Metionina/metabolismo , Suplementos Dietéticos/análisis , Rumen/metabolismo , Dieta/veterinaria , Racemetionina/metabolismo , Músculo Esquelético/metabolismo , Desarrollo Fetal , Expresión Génica , Alimentación Animal/análisis
9.
Environ Sci Pollut Res Int ; 31(7): 10994-11009, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38214855

RESUMEN

This study explores the impact of a novel approach on the levels of SWI (saltwater intrusion) and NO3- (nitrate) contamination. Some numerical simulations were conducted utilizing a coupled model that incorporates variably saturation and density, as well as convection diffusion reaction within a sandy coastal aquifer. We verified the reliability of the model for SWI based on comparison lab experiments and for chemical reactions based on a comparison of previous in situ observations. Cutoff walls and subsurface dams cannot simultaneously control SWI and reduce NO3- contamination. A novel approach that combines subsurface dams and permeable CH2O (organic carbon) walls (PC-Wall) is proposed. Subsurface dams are utilized to prevent SWI, while PC-Walls are employed to mitigate NO3- pollution. Results demonstrate that the construction of a PC-Wall with a concentration of 1.0 mM facilitated a transition from nitrification (Ni)-dominated to denitrification (Dn)-dominated. An increase in CH2O concentration to 1.0 mM caused a significant 1942.5 % rise in mDn (the mass of NO3- removed through Dn). Increment of the distance between the PC-Wall and the ocean from 35 to 45 m could result in a 103.7 % mDn increase and reduce mN (the compound mass of NO3- remaining in the aquifer) by 11.7 %. The study offers a detailed comprehension of the intricate hydrodynamics of SWI and NO3- pollution. In addition, it provides design guidance for engineering to mitigate contamination by NO3- and controlling SWI, thus fostering the management of groundwater quality.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Nitratos/análisis , Agua de Mar/química , Arena , Carbono , Reproducibilidad de los Resultados , Agua Subterránea/química , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis
10.
Sci Total Environ ; 912: 169136, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38072273

RESUMEN

The use of tailings dams in the mining industry is recurrent and a matter of concern given the risk of collapse. The planning of tailings dam's emplacement usually attends construction design criteria and site geotechnical properties, but often neglects the risk of installing the depositional facilities in potentially unstable landscapes, namely those characterized by steep slopes and(or) high drainage densities. In order to help bridging this gap, the present study developed a framework model whereby geomorphologic vulnerability is assessed by a set of morphometric parameters (e.g., drainage density; relief ratio; roughness coefficient). Using the Ribeirão Ferro-Carvão micro-basin (3265.16 ha) as test site, where six dams currently receive tailings from the mining of iron-ore deposits in the Brumadinho region (Minas Gerais, Brazil) and one has collapsed in 25 January 2019 (the B1 dam of Córrego do Feijão mine of Vale, S.A.), the risk of dam instability derived from geomorphologic vulnerability was assessed and alternative suitable locations were highlighted when applicable. The results made evident the location of five dams (including the collapsed B1) in high-risk regions and two in low-risk regions, which is preoccupying. The alternative locations represent 58 % of Ribeirão Ferro-Carvão micro-basin, which is a reasonable and workable share. Overall, the study exposed the fragility related with tailings dams' geography, which is not restricted to the studied micro-basin, because dozens of active tailings dams exist in the parent basin (the Paraopeba River basin) that can also be vulnerable to geomorphologically-dependent hydrologic hazards such as intensive erosion, valley incision or flash floods. Attention to this issue is therefore urgent to prevent future tragedies related with tailings dams' breaks, in the Paraopeba River basin or elsewhere, using the proposed framework model as guide.

11.
Integr Environ Assess Manag ; 20(3): 616-644, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37526129

RESUMEN

Environmental impact assessment (EIA) has been widely criticized by the aquatic science community for poorly aligned approaches when selecting endpoints and collecting data during the baseline, predictive modeling, and postdevelopment monitoring phases. If these critical phases of the EIA process are not aligned properly, it can be difficult to evaluate the presence of postdevelopment effects. Examples of the misalignment of these phases include baseline studies failing to measure indicators that are monitored postdevelopment; predictive assessments that do not quantitatively predict conditions or potential impacts postdevelopment; and the failure to identify relevant indicators that may detect effects postdevelopment. For aquatic assessments, understanding how to protect critical ecosystem attributes to satisfy regulatory concerns could help to better align aquatic science monitoring activities across EIA phases. In this article we investigate recent Canadian hydroelectric dam EIAs to evaluate how well recent assessment approaches are meeting these necessary conditions of good aquatic EIA practice through the lens of ecosystem services from a fish's perspective. We found that larger facilities generally had baseline studies and modeling that better supported postdevelopment monitoring, but improvements in structure, linkages, and expectations would better align EIA phases in a manner that would improve assessments and environmental protection. Integr Environ Assess Manag 2024;20:616-644. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

12.
Environ Res ; 242: 117729, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38036204

RESUMEN

The Yangtze River Basin, the world's third-largest river basin and a hot spot for global biodiversity conservation, is facing biodiversity crisis caused by reduced river connectivity. The deterioration arises from four dimensions: longitudinal, lateral, vertical and temporal. However, limited research has quantified the spatiotemporal connectivity of the Yangtze River Basin and further evaluated the consequent impact on fish biodiversity. In our study, a multi-index evaluation framework was developed to assess the variations in the four-dimensional connectivity of the Yangtze River Basin from 1980 to 2020, and fish biodiversity affected by reduced connectivity was detected by environmental DNA metabarcoding. Our results showed that the Yangtze River Basin suffers from a pronounced connectivity reduction, with 67% of assessed rivers experiencing deteriorated connectivity in recent years. The lost fish biodiversity along the river reaches with the worst connectivity was likely attributed to the construction of hydropower plants. The headwaters and the downstreams of most hydropower plants had a higher fish biodiversity compared with reservoirs. The free-flowing reaches in the downstream of the lowest hydropower station, had higher lotic fish abundance compared with that in the upstream. As for the entire Yangtze River Basin, 67% of threatened fish species, with 70% endemic species, were threatened by reduced river connectivity. Our result indicates that the massive loss of river connectivity changes the spatiotemporal patterns of fish community and threatens protected fish. More effective measures to restore the populations of affected fish in rivers with reduced river connectivity are required.


Asunto(s)
Biodiversidad , Ríos , Animales , Peces , Ecosistema
13.
Braz. dent. sci ; 27(1): 1-7, 2024. ilus, tab
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1551411

RESUMEN

Objective: The aim of the study was to report the aplicability of intraoral scanning while rubber dam isolation is in place. Material and Methods: Female patient, 50 years old, required restorative procedures on teeth 35 and 37. An intraoral scan was initially performed on both arches. Isolation was carried out from 33 to 37, tooth preparation and immediate dentin sealing were carried out. A new scan with the rubber dam in place was performed and a CAD/CAM lithium disilicate hybrid block was digitally designed, milled, crystallized and cemented under the tooth surface with the rubber dam still in position. After completing this stage, the rubber dam was removed, the occlusion was verified, presenting excellent aesthetic and functional results. Results: The absolute isolation process used in the present study works as an excellent device for gingival retraction. Conclusion: The absolute isolation can be recommended in clinical activities of intraoral scanning favoring the quality of the final result of treatments (AU)


Objetivo: O objetivo do estudo foi relatar a aplicabilidade do escaneamento intraoral sob isolamento absoluto. Material e Métodos: Paciente do sexo feminino, 50 anos, necessitou de procedimentos restauradores nos dentes 35 e 37. Uma varredura intraoral foi inicialmente realizada em ambos os arcos. O isolamento absoluto foi feito de 33 a 37, permitindo a realização do preparo dentário e selamento imediato da dentina. Um novo escaneamento com o dique de borracha colocado foi realizado e um bloco híbrido de dissilicato de lítio CAD/CAM foi projetado digitalmente, fresado, cristalizado e cimentado sob a superfície dentária ainda com o dique de borracha em posição. Após a finalização dessa etapa, o dique de borracha foi removido, a oclusão foi verificada apresentando ótimos resultados estéticos e funcionais. Resultados: O isolamento absoluto utilizado no presente estudo funciona como um excelente dispositivo para retração gengival. Conclusão: O isolamento absoluto pode ser recomendado em atividades clínicas de escaneamento intraoral favorecendo a qualidade do resultado final dos tratamentos (AU)


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Dique de Goma , Diseño Asistido por Computadora , Ajuste de Precisión de Prótesis , Tecnología Digital , Rehabilitación Bucal
14.
Braz. oral res. (Online) ; 38: e009, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1528144

RESUMEN

Abstract This study was a randomized controlled clinical trial with two parallel arms and the objective was to compare the survival of resin modified glass ionomer (RMGIC) restorations in primary teeth using rubber dam or cotton roll isolation after a 30-month follow-up period. Ninety-two children (mean age 6.8 ± 1.37) and 200 primary molars with occlusal or occluso-proximal cavitated dentin caries lesions were randomly assigned into two groups: cotton rolls and rubber dam. All lesions were restored using RMGIC (RIVA Light Cure) after selective caries removal. Restorative failure and lesion arrestment were evaluated by two independent, trained, and calibrated examiners through clinical and radiographic examinations. The Kaplan-Meier test was used to assess the survival of restorations and Cox regression was used to assess the association of risk factors with restorative failure. There was no significant difference in survival rates between groups (p = 0.17). Older age (HR = 2.81 [95%CI: 1.47-5.44]) and higher rate of gingival bleeding (HR = 0.47 [95%CI: 0.23-0.99]) were associated with restorative failure. No patient had painful symptoms, pulp outcomes, or radiographic changes compatible with lesion progression. The use of rubber dam isolation did not increase the survival rate of occlusal and occluso-proximal restorations using RMGIC in primary molars after 30 months of follow-up. Since the survival is not influenced by the type of isolation, the professional can safely choose the appropriate technique for each case, considering his experience and preferences, as well as those of the patient.

15.
Restor Dent Endod ; 48(4): e32, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38053779

RESUMEN

Ingestions and aspirations of foreign bodies are rare, but do occasionally occur during dental treatment. Although reports exist, few include photos demonstrating the extensive surgical intervention that may be necessary to manage such events. Perhaps this lack of visualization, and associated lack of awareness, is one of the reasons some clinicians still provide non-surgical root canal therapy (NSRCT) without a rubber dam. This case report outlines the medical treatment of a 30-year-old male who initially presented to a general dentist's office (not associated with the authors) for NSRCT of their mandibular right first molar. A rubber dam was not used for this procedure, during which the accidental ingestion of an endodontic K-file occurred. The patient was subsequently hospitalized for evaluation and treatment, consisting of numerous imaging studies, endoscopic evaluation, and surgical removal of the file from his small intestine. The ingestion of foreign bodies, and the associated complications, can be reduced through the routine use of a rubber dam, which is considered the standard of care for NSRCT. This case graphically illustrates the potential consequences associated with deviating from the standard of care and should remind clinicians that a rubber dam is necessary for all cases of NSRCT.

16.
Sensors (Basel) ; 23(24)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38139664

RESUMEN

Hydropower facilities are often remotely monitored or controlled from a centralized remote control room. Additionally, major component manufacturers monitor the performance of installed components, increasingly via public communication infrastructures. While these communications enable efficiencies and increased reliability, they also expand the cyber-attack surface. Communications may use the internet to remote control a facility's control systems, or it may involve sending control commands over a network from a control room to a machine. The content could be encrypted and decrypted using a public key to protect the communicated information. These cryptographic encoding and decoding schemes become vulnerable as more advances are made in computer technologies, such as quantum computing. In contrast, quantum key distribution (QKD) and other quantum cryptographic protocols are not based upon a computational problem, and offer an alternative to symmetric cryptography in some scenarios. Although the underlying mechanism of quantum cryptogrpahic protocols such as QKD ensure that any attempt by an adversary to observe the quantum part of the protocol will result in a detectable signature as an increased error rate, potentially even preventing key generation, it serves as a warning for further investigation. In QKD, when the error rate is low enough and enough photons have been detected, a shared private key can be generated known only to the sender and receiver. We describe how this novel technology and its several modalities could benefit the critical infrastructures of dams or hydropower facilities. The presented discussions may be viewed as a precursor to a quantum cybersecurity roadmap for the identification of relevant threats and mitigation.

17.
Front Microbiol ; 14: 1291464, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37954247

RESUMEN

Dams are increasingly disrupting natural river systems, yet studies investigating their impact on microbial communities at regional scale are limited. Given the indispensable role of bacterioplankton in aquatic ecosystems, 16S rRNA gene sequencing was performed to explore how these communities respond to dam-influenced environmental changes at the regional scale in the Shaying River Basin. Our findings revealed that cascade dams create distinct environments, shaping bacterioplankton communities near the dams differently from those in natural rivers. In the upstream of the cascade dams, water quality was superior, while bacterioplankton community structure was simple with weak community interactions. In the midstream, nutrient and heavy metal content were increased, making bacterioplankton structures more susceptible to environmental changes. In the downstream of the cascade dams, water quality had a significant impact on the community and the bacterioplankton structures were highly complex. Additionally, environmental variables significantly influenced bacterioplankton functional groups. However, the response to these factors, as well as the interplay between functional and taxonomic diversity, varied markedly depending on the specific region of the cascade dams. We here delved into the effects of cascade dams on the taxonomic diversity and functional groups of bacterioplankton to provide a theoretical basis for segmentally regulating these dams.

18.
Trop Anim Health Prod ; 55(5): 351, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37798590

RESUMEN

This experiment was carried out to study the effect of acetic acid addition to rice straws that had been already treated with urea on chemical composition, digestibility, nutritive value, and productive performance of ewes. Thirty ewes with an initial body weight of 44 ± 0.41 kg were chosen 7 days after parturition and divided into 3 groups (10 of each) for 3 months. Each group was assigned randomly to receive one of the three experimental rations composed of concentrate feed mixture and untreated rice straw as a control group (G1), urea-treated rice straw (G2), and urea-acetic acid-treated rice straw (G3). Digestibility coefficients and nutritive value were determined using fifteen mature rams and blood samples were obtained at the end of the collecting period. Findings indicated that the crude protein of rice straw was increased, and crude fiber content was decreased by either urea or urea-acetic acid rations (i.e., G2 and G3). Digestibility of most nutrients was increased (P < 0.05) for animals fed either G2 or G3 rations. There were no significant differences in nutritive value as total digestible nutrients (TDN) among tested groups; however, digestible crude protein (DCP) increased (P < 0.05) for G2 and G3 rations. Plasma total protein, AST, creatinine, and urea were increased (P < 0.05) by feeding on G2 or G3 ration; however, plasma ALT was not affected. The average daily intake of dry matter (DM), TDN, and DCP was higher for G2 and G3 rations. Actual milk yield, fat-corrected milk (FCM), percentages of fat, and total solids and constituents yield were increased (P < 0.05) by feeding on treated rice straw rations (i.e., G2 and G3); however, the percentages of protein, lactose, solids not fat, and ash were not affected. In the 1st month after parturition, the changes in ewes body weight were less (P < 0.05) when they fed on G2 and G3 rations than the control one (G1)). Dams' production and offspring performance were improved (P < 0.05) by feeding on G2 and G3 rations. Feed conversion as kg DMI/kg FCM, kg TDN/kg FCM, and economic efficiency was improved for G2 and G3. In concluded, adding acetic acid to urea-treated rice straw may improve the performance of ewes fed on it and increase their milk production and profitability. The same trend was observed with (G2) which received urea-treated rice straw ration.


Asunto(s)
Oryza , Animales , Femenino , Masculino , Ácido Acético/metabolismo , Alimentación Animal/análisis , Peso Corporal , Dieta/veterinaria , Digestión , Lactancia , Leche/química , Ovinos , Oveja Doméstica , Urea/metabolismo
19.
J Environ Manage ; 346: 118951, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37738721

RESUMEN

Dams are ones of the main sources of anthropogenic disturbance to the ecology and geomorphology of rivers. The aim of the present study is to understand the mechanisms underlying their influence on downstream bedload transport in three gravel-bed rivers in the Morvan massif, France. The hydrological disturbance caused by four dams is examined at a short (2.4-2.7 years) and longer (21-28 year) time scale. At the short time scale, bedload displacement was monitored (RFID) at 8 study sites around the dams. Morpho-sedimentary characterization of the bed substrate was performed at the study sites and combined with analyses of the long profile evolution and the current cross profile. The flood regime has been to a varying extent durably reduced by the dams depending on their size and purpose: the mean annual maximum flood was reduced by 9 to 40% and the number of flood events by 27 to 73.5% over the 21-28 years period. Sediment availability and loose structures were found above the dams and below medium-sized dams (<10 m) with a null or moderate influence on the flood regime (configuration I). Sediment deficit, consolidated structures, bed coarsening and vegetation encroachment were observed within 20 km downstream of large dams (>15 m) influencing strongly or moderately the flood regime (configuration II). These morpho-sedimentary features significantly affect the current bedload dynamics, creating conditions more or less favorable for the mobility of the present and incoming bedload. The cumulative mean bedload distances of RFID tracers in configuration II are significantly lower (6.8-45 m) than in configuration I (78-315 m). The current flow management of the dams has only a moderate effect on the bedload distances recorded, as shown by the mean virtual bedload velocities, which confirm the different dynamics (0.42-0.91 m/d, and 0.62-6.44 m/d, for II and I respectively). Our results demonstrate how modifications of dams on flow and bedload discharge altered the downstream morphology, but also that this inherited morphology may now be the main controlling factor of bedload transport. These findings invite further discussion about the most appropriate ways to restore rivers downstream of dams when dealing with multi-decadal inherited morphological features.


Asunto(s)
Ecología , Hidrología , Ríos/química , Inundaciones , Francia
20.
Environ Res ; 238(Pt 1): 117128, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37716382

RESUMEN

Water runoff and soil erosion by water from agricultural fields lead to a loss of water available for plant growth, loss of topsoil and transport of plant protection products (PPPs), hence constituting contaminant pathways to adjacent surface water. Several mitigation measures are used, including small earthen dams or depressions, referred to as micro-dams. This practice has been applied worldwide since the 1930s. In the regulatory exposure assessment for the registration of PPPs, runoff curve numbers (CNs) are used in the PRZM model to quantify runoff and the effect of mitigation measures. An overview of the pertinent literature is presented to enlarge the knowledge base to give robust recommendations for the inclusion of the practice in the regulatory exposure assessment of PPPs. Literature on micro-dams was collected here in a review of the reported results from field trials in terms of runoff, erosion, and PPP transport mitigation. Selected data were further evaluated to derive runoff CNs. From 21 studies with 252 individual setups and trials, we derived a geometric mean reduction of runoff of 62% (42%-90%); results for maize and potatoes only were 62% (53%-73%) and 81% (71%-93%), respectively. Erosion was reduced by 73% (60%-90%; maize: 75% [63%-88%]; potatoes 89% [83%-97%]). From 19 studies with 246 individual setups and trials, the geometric mean of the CN reduction is 11% (4%-25%; maize: 7% [3%-17%], potatoes: 14% [6%-36%]). For PPP transport (5 studies; 10 different PPP), a geometric mean reduction of 67% (48%-94%) was derived (maize: 56% [38%-81%; 3 studies; 10 PPP]; potatoes: 91% [1 study; 4 PPP]). The application of micro-dams provides considerable reductions and can therefore be factored into the environmental exposure assessment by using percent reductions of runoff, erosion, and PPP transport or lowering the runoff CN in numerical modelling.


Asunto(s)
Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Erosión del Suelo , Exposición a Riesgos Ambientales , Agua , Suelo
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