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1.
Sci Rep ; 14(1): 282, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168501

RESUMO

The insular region of Wallacea has become a focal point for studying Pleistocene human ecological and cultural adaptations in island environments, however, little is understood about early burial traditions during the Pleistocene. Here we investigate maritime interactions and burial practices at Ratu Mali 2, an elevated coastal cave site on the small island of Kisar in the Lesser Sunda Islands of eastern Indonesia dated to 15,500-3700 cal. BP. This multidisciplinary study demonstrates extreme marine dietary adaptations, engagement with an extensive exchange network across open seas, and early mortuary practices. A flexed male and a female, interred in a single grave with abundant shellfish and obsidian at Ratu Mali 2 by 14.7 ka are the oldest known human burials in Wallacea with established funerary rites. These findings highlight the impressive flexibility of our species in marginal environments and provide insight into the earliest known ritualised treatment of the dead in Wallacea.


Assuntos
Arqueologia , Sepultamento , Humanos , Masculino , Feminino , Indonésia , Cavernas , Práticas Mortuárias
2.
Am J Biol Anthropol ; 183(1): 141-156, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37925739

RESUMO

OBJECTIVES: There are few bioarcheological analyses of life experiences in colonial period Aotearoa New Zealand, despite this being a time of major adaptation and social change. In our study, early life histories are constructed from multi-isotope and enamel peptide analysis of permanent first molars associated with Victorian era dental practices operating between AD 1881 and 1905 in Invercargill. Chemical analyses of the teeth provide insight into the childhood feeding practices, diet, and mobility of the people who had their teeth extracted. MATERIALS AND METHODS: Four permanent left mandibular first molars were analyzed from a cache of teeth discovered at the Leviathan Gift Depot site during excavations in 2019. The methods used were: (1) enamel peptide analysis to assess chromosomal sex; (2) bulk (δ13 Ccarbonate ) and incremental (δ13 Ccollagen and δ15 N) isotope analysis of dentin to assess childhood diet; and (3) strontium (87 Sr/86 Sr) and oxygen (δ18 O) isotope analysis of enamel to assess childhood residency. Two modern permanent first molars from known individuals were analyzed as controls. RESULTS: The archaeological teeth were from three chromosomal males and one female. The protein and whole diets were predominately based on C3 -plants and domestic animal products (meat and milk). A breastfeeding signal was only identified in one historic male. All individuals likely had childhood residences in Aotearoa. DISCUSSION: Unlike most bioarcheological studies that rely on the remains of the dead, the teeth analysed in this study were extracted from living people. We suggest that the dental patients were likely second or third generation colonists to Aotearoa, with fairly similar childhood diets. They were potentially lower-class individuals either living in, or passing through, the growing colonial center of Invercargill.


Assuntos
Isótopos , Dente , Masculino , Feminino , Animais , Humanos , Criança , Nova Zelândia , Isótopos/análise , Dente/química , Dente Molar/química , Peptídeos
3.
Sci Total Environ ; 902: 166399, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37611704

RESUMO

The growth of phytoplankton in lakes is thought to be primarily controlled by macronutrient concentrations, but the availability of trace metal micronutrients, such as iron (Fe), are increasingly recognised as important regulators of lake primary production. This study evaluates the role of Fe in regulating phytoplankton growth in lakes of different nutrient status in New Zealand. The results of this unique year-long study, combining highly sensitive trace metal concentration analysis of waters and particulates with advanced trace metal bioavailability and speciation modelling, constrains thresholds for bioavailable Fe and colloidal Fe of 0.8 nmol·L-1 and 30 nmol·L-1, respectively, below which phytoplankton growth-limitation occurs. These thresholds specifically control diatom bloom formation and termination in lakes, thereby exerting a strong influence on freshwater carbon sequestration, given the dominance of diatoms in lake bloom assemblages. Importantly, potentially toxic cyanobacteria thrived only after events of bottom water anoxia, when additional dissolved Fe in concentrations ≥4 nmol·L-1 was released into the water column. These new thresholds for bioavailable and colloidal Fe offer the potential to manage micronutrient levels in lakes for the purpose of regulating algal bloom formation and carbon sequestration, while at the same time, suppressing the formation of harmful cyanobacterial blooms.


Assuntos
Cianobactérias , Oligoelementos , Fitoplâncton , Lagos/microbiologia , Ferro , Eutrofização , Nutrientes , Água
4.
J Acquir Immune Defic Syndr ; 93(1): 55-63, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36706362

RESUMO

OBJECTIVES: This uncontrolled pilot study examined the feasibility, acceptability, and preliminary HIV and psychological health effects of iTHRIVE 365, a multicomponent intervention designed by and for Black same gender loving men (SGLM) to promote: health knowledge and motivation, Black SGLM social support, affirming health care, and housing and other economic resources. DESIGN METHODS: We conducted a 14-day daily diary study with 32 Black SGLM living with HIV connected to THRIVE SS in Atlanta, GA. Daily surveys assessed intervention engagement, antiretroviral medication (ART) use, depressive symptoms, anxiety symptoms, and emotion regulation difficulties. App paradata (ie, process data detailing app usage) assessed amount of intervention engagement via page access. Participants began receiving access to the intervention on day 7. After the 14-day daily diary period, participants responded to follow-up items on the user-friendliness, usefulness, helpfulness, and whether they would recommend iTHRIVE 365 to others. Chi-square analyses examined associations between intervention engagement and ART use, and dynamic structural equation modelling assessed longitudinal associations from intervention engagement to next-day psychological health. This intervention trial is registered on ClinicalTrials.gov (NCT05376397). RESULTS: On average, participants engaged with iTHRIVE 365 over once every other day and accessed intervention pages 4.65 times per day. Among participants who engaged with the intervention, 78% reported it was helpful to extremely helpful, 83% reported it was moderately to extremely useful, and 88% reported it was user-friendly and they would recommend it to others. On intervention engagement days, participants had higher odds of ART use, χ 2 (1) = 4.09, P = 0.04, than intervention nonengagement days. On days after intervention engagement, participants showed non-null decreases in depressive symptoms (τ = -0.14; 95% CI : = [-0.23, -0.05]) and emotion regulation difficulties (τ = -0.16; 95% CI : = [-0.24, -0.02]). CONCLUSIONS: Findings suggest iTHRIVE 365 is feasible, acceptable, and positively affects daily ART use, depressive symptoms, and emotion regulation difficulties.


Assuntos
Infecções por HIV , Humanos , Masculino , Antirretrovirais/uso terapêutico , Estudos de Viabilidade , Infecções por HIV/tratamento farmacológico , Motivação , Projetos Piloto
5.
J Health Care Poor Underserved ; 34(3S): 7-12, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38661911

RESUMO

Undetectables Atlanta (UA), a peer support network for Black gay men living with HIV, conducted an exploratory evaluation to begin identifying outcomes of UA membership. Th is initial evaluation suggested decreased HIV stigma and increased comfort with disclosure, treatment adherence, and other areas of well-being that warrant prospective evaluation.


Assuntos
Negro ou Afro-Americano , Infecções por HIV , Homossexualidade Masculina , Grupo Associado , Estigma Social , Humanos , Masculino , Infecções por HIV/etnologia , Infecções por HIV/psicologia , Infecções por HIV/terapia , Negro ou Afro-Americano/psicologia , Homossexualidade Masculina/psicologia , Homossexualidade Masculina/etnologia , Adulto , Apoio Social , Georgia , Pessoa de Meia-Idade , Disparidades nos Níveis de Saúde
6.
Environ Sci Technol ; 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36480454

RESUMO

The European and U.S. chemical agencies have listed approximately 800k chemicals about which knowledge of potential risks to human health and the environment is lacking. Filling these data gaps experimentally is impossible, so in silico approaches and prediction are essential. Many existing models are however limited by assumptions (e.g., linearity and continuity) and small training sets. In this study, we present a supervised direct classification model that connects molecular descriptors to toxicity. Categories can be driven by either data (using k-means clustering) or defined by regulation. This was tested via 907 experimentally defined 96 h LC50 values for acute fish toxicity. Our classification model explained ≈90% of the variance in our data for the training set and ≈80% for the test set. This strategy gave a 5-fold decrease in the frequency of incorrect categorization compared to a quantitative structure-activity relationship (QSAR) regression model. Our model was subsequently employed to predict the toxicity categories of ≈32k chemicals. A comparison between the model-based applicability domain (AD) and the training set AD was performed, suggesting that the training set-based AD is a more adequate way to avoid extrapolation when using such models. The better performance of our direct classification model compared to that of QSAR methods makes this approach a viable tool for assessing the hazards and risks of chemicals.

7.
J Hazard Mater ; 435: 129032, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35650740

RESUMO

Road pollution is one of the major sources of microplastic particles to the environment. The distribution of tire, polymer-modified bitumen (PMB) and tire and road wear particles (TRWP) in different tunnel compartments were explored: road surface, gully-pots and tunnel wash water. A new method for calculating TRWP using Monte Carlo simulation is presented. The highest concentrations on the surface were in the side bank (tire:13.4 ± 5.67;PMB:9.39 ± 3.96; TRWP:22.9 ± 8.19 mg/m2), comparable to previous studies, and at the tunnel outlet (tire:7.72 ± 11.2; PMB:5.40 ± 7.84; TRWP:11.2 ± 16.2 mg/m2). The concentrations in gully-pots were highest at the inlet (tire:24.7 ± 26.9; PMB:17.3 ± 48.8; TRWP:35.8 ± 38.9 mg/g) and comparable to values previously reported for sedimentation basins. Untreated wash water was comparable to road runoff (tire:38.3 ± 10.5; PMB:26.8 ± 7.33; TRWP:55.3 ± 15.2 mg/L). Sedimentation treatment retained 63% of tire and road wear particles, indicating a need to increase the removal efficiency to prevent these from entering the environment. A strong linear relationship (R2-adj=0.88, p < 0.0001) between total suspended solids (TSS) and tire and road wear rubber was established, suggesting a potential for using TSS as a proxy for estimating rubber loads for monitoring purposes. Future research should focus on a common approach to analysis and calculation of tire, PMB and TRWP and address the uncertainties related to these calculations.


Assuntos
Microplásticos , Material Particulado , Material Particulado/análise , Plásticos , Borracha , Água
8.
Environ Sci Eur ; 34(1): 21, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281760

RESUMO

The chemical pollution crisis severely threatens human and environmental health globally. To tackle this challenge the establishment of an overarching international science-policy body has recently been suggested. We strongly support this initiative based on the awareness that humanity has already likely left the safe operating space within planetary boundaries for novel entities including chemical pollution. Immediate action is essential and needs to be informed by sound scientific knowledge and data compiled and critically evaluated by an overarching science-policy interface body. Major challenges for such a body are (i) to foster global knowledge production on exposure, impacts and governance going beyond data-rich regions (e.g., Europe and North America), (ii) to cover the entirety of hazardous chemicals, mixtures and wastes, (iii) to follow a one-health perspective considering the risks posed by chemicals and waste on ecosystem and human health, and (iv) to strive for solution-oriented assessments based on systems thinking. Based on multiple evidence on urgent action on a global scale, we call scientists and practitioners to mobilize their scientific networks and to intensify science-policy interaction with national governments to support the negotiations on the establishment of an intergovernmental body based on scientific knowledge explaining the anticipated benefit for human and environmental health.

9.
Sci Rep ; 12(1): 3164, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210443

RESUMO

Longitudinal movement plays fundamental role in habitat colonization and population establishment of many riverine fish species. Movement patterns of amphidromous fish species at fine-scales that would allow characterizing the direction of movement and factors associated with the establishment of specific life-history strategies (resident or amphidromous) in rivers are still poorly understood. We assess fine-scale longitudinal movement variability patterns of facultative amphidromous fish species Galaxias maculatus in order to unfold its life-history variation and associated recruitment habitats. Specifically, we analyzed multi-elemental composition along core to edge transects in ear-bones (otoliths) of each fish using recursive partitions that divides the transect along signal discontinuities. Fine-scale movement assessment in five free-flowing river systems allowed us to identify movement direction and potential recruitment habitats. As such, resident recruitment of G. maculatus in freshwater (71%) and estuarine (24%) habitats was more frequent than amphidromous recruitment (5%), and was linked to availability of slow-flowing lotic or lentic habitats that produce or retain small-bodied prey consumed by their larvae. We postulate that life-history variation and successful recruitment of facultative amphidromous fish such as G. maculatus in river systems is driven by availability of suitable recruitment habitats and natural hydrologic connectivity that allows fish movement to these habitats.


Assuntos
Migração Animal , Comportamento Animal , Peixes/fisiologia , Osmeriformes/fisiologia , Animais , Ecossistema , Água Doce , Rios
10.
Sci Total Environ ; 824: 153785, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35182629

RESUMO

According to estimates put forward in multiple studies, tire and road wear particles are one of the largest sources to microplastic contamination in the environment. There are large uncertainties associated with local emissions and transport of tire and road wear particles into environmental compartments, highlighting an urgent need to provide more data on inventories and fluxes of these particles. To our knowledge, the present paper is the first published data on mass concentrations and snow mass load of tire and polymer-modified road wear particles in snow. Roadside snow and meltwater from three different types of roads (peri-urban, urban highway and urban) were analysed by Pyrolysis Gas Chromatography Mass Spectrometry. Tire particle mass concentrations in snow (76.0-14,500 mg/L meltwater), and snow mass loads (222-109,000 mg/m2) varied widely. The concentration ranges of polymer-modified particles were 14.8-9550 mg/L and 50.0-28,800 mg/m2 in snow and meltwater, respectively. Comparing the levels of tire and PMB particles to the total mass of particles, showed that tire and PMB-particles combined only contribute to 5.7% (meltwater) and 5.2% (mass load) of the total mass concentration of particles. The large variation between sites in the study was investigated using redundancy analysis of the possible explanatory variables. Contradictory to previous road studies, speed limit was found to be one of the most important variables explaining the variation in mass concentrations, and not Annual Average Daily Traffic. All identified variables explained 69% and 66%, for meltwater and mass load concentrations, respectively. The results show that roadside snow contain total suspended solids in concentrations far exceeding release limits of tunnel and road runoff, as well as tire particles in concentrations comparable to levels previously reported to cause toxicity effects in organisms. These findings strongly indicate that roadside snow should be treated before release into the environment.


Assuntos
Microplásticos , Plásticos , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Polímeros , Neve , Emissões de Veículos/análise
11.
Sci Rep ; 12(1): 467, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013511

RESUMO

Freshwater phytoplankton blooms are increasing in prevalence and there are conflicting views on whether trace metals limit growth of key species and thus bloom formation. The Taupo Volcanic Zone (TVZ), New Zealand, was formed by multiple eruptions of a super-volcano which emitted rhyolitic tephra leaving lakes depleted in trace metals. This provides an opportunity to test the potential of trace metal limitation on freshwater phytoplankton growth under nanomolar concentrations. Growth responses of two algal species isolated from Lake Taupo, Dolichospermum lemmermannii (cyanobacteria) and Fragilaria crotonensis (diatom), to six biologically important trace metals (manganese, iron, zinc, cobalt, copper and molybdenum) were examined in culture experiments. These were conducted at three trace metal concentrations: (1) ambient, (2) two-times ambient, and (3) ten-times ambient concentrations in Lake Taupo. Elevated concentrations of iron significantly increased growth rates and maximum cell densities in D. lemmermannii, whereas no significant concentration dependence was observed for other trace metals. Fragilaria crotonensis showed no significant growth response to elevated concentrations of trace metals. These results highlight the importance of iron as a growth limiting nutrient for cyanobacteria and indicate that even small (twofold) increases in Fe concentrations could enhance cyanobacteria growth rates in Lake Taupo, potentially causing cyanobacterial blooms.


Assuntos
Cianobactérias/crescimento & desenvolvimento , Diatomáceas/crescimento & desenvolvimento , Lagos/química , Fitoplâncton/crescimento & desenvolvimento , Oligoelementos/análise , Cianobactérias/metabolismo , Diatomáceas/metabolismo , Ferro/análise , Ferro/metabolismo , Nova Zelândia , Nutrientes/análise , Nutrientes/metabolismo , Fitoplâncton/metabolismo , Oligoelementos/metabolismo
12.
Anal Chem ; 93(49): 16562-16570, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34843646

RESUMO

Centroiding is one of the major approaches used for size reduction of the data generated by high-resolution mass spectrometry. During centroiding, performed either during acquisition or as a pre-processing step, the mass profiles are represented by a single value (i.e., the centroid). While being effective in reducing the data size, centroiding also reduces the level of information density present in the mass peak profile. Moreover, each step of the centroiding process and their consequences on the final results may not be completely clear. Here, we present Cent2Prof, a package containing two algorithms that enables the conversion of the centroided data to mass peak profile data and vice versa. The centroiding algorithm uses the resolution-based mass peak width parameter as the first guess and self-adjusts to fit the data. In addition to the m/z values, the centroiding algorithm also generates the measured mass peak widths at half-height, which can be used during the feature detection and identification. The mass peak profile prediction algorithm employs a random-forest model for the prediction of mass peak widths, which is consequently used for mass profile reconstruction. The centroiding results were compared to the outputs of the MZmine-implemented centroiding algorithm. Our algorithm resulted in rates of false detection ≤5% while the MZmine algorithm resulted in 30% rate of false positive and 3% rate of false negative. The error in profile prediction was ≤56% independent of the mass, ionization mode, and intensity, which was 6 times more accurate than the resolution-based estimated values.


Assuntos
Aprendizado de Máquina
13.
Sci Data ; 8(1): 223, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429429

RESUMO

Non-target analysis (NTA) employing high-resolution mass spectrometry is a commonly applied approach for the detection of novel chemicals of emerging concern in complex environmental samples. NTA typically results in large and information-rich datasets that require computer aided (ideally automated) strategies for their processing and interpretation. Such strategies do however raise the challenge of reproducibility between and within different processing workflows. An effective strategy to mitigate such problems is the implementation of inter-laboratory studies (ILS) with the aim to evaluate different workflows and agree on harmonized/standardized quality control procedures. Here we present the data generated during such an ILS. This study was organized through the Norman Network and included 21 participants from 11 countries. A set of samples based on the passive sampling of drinking water pre and post treatment was shipped to all the participating laboratories for analysis, using one pre-defined method and one locally (i.e. in-house) developed method. The data generated represents a valuable resource (i.e. benchmark) for future developments of algorithms and workflows for NTA experiments.


Assuntos
Benchmarking , Água Potável/análise , Espectrometria de Massas , Algoritmos , Laboratórios , Fluxo de Trabalho
14.
Nutrients ; 13(4)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33806205

RESUMO

Anemia is a significant comorbidity for older adults not fully attributable to iron deficiency. Low-grade inflammation and other micronutrient deficiencies also contribute. This cross-sectional study examined the relationships between nutrient and non-nutrient factors with hemoglobin and anemia in 285 residents (>65 years) of 16 New Zealand aged-care facilities. Blood samples were analyzed for hemoglobin, ferritin, sTfR, hepcidin, zinc, selenium, and interleukin-6 (IL-6), (with ferritin, sTfR, zinc and selenium adjusted for inflammation). Linear regression models examined the relationships between micronutrient biomarkers (iron, zinc, selenium, vitamin B-12 and D), age, sex, and health factors with hemoglobin. Thirty-two percent of participants exhibited anemia, although <2% had either depleted iron stores or iron deficiency. Plasma zinc and selenium deficiencies were present in 72% and 38% of participants, respectively. Plasma zinc and total body iron (TBI) were positively associated (p < 0.05) with hemoglobin, while gastric acid suppressing medications, hepcidin, and interleukin-6 were inversely associated. These relationships were maintained after the application of anemia cut-offs. These findings emphasize the importance of considering multiple micronutrient deficiencies as risk factors for anemia.


Assuntos
Anemia/sangue , Avaliação Geriátrica/métodos , Ferro/sangue , Selênio/sangue , Zinco/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos Transversais , Feminino , Instituição de Longa Permanência para Idosos , Humanos , Masculino , Micronutrientes/sangue , Nova Zelândia , Estado Nutricional
15.
Environ Int ; 153: 106540, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33838618

RESUMO

The COVID-19 outbreak has forced countries to introduce severe restrictive measures to contain its spread. In particular, physical distancing and restriction of movement have had important consequences on human behaviour and potentially also on illicit drug use and supply. These changes can be associated with additional risks for users, in particular due to reduced access to prevention and harm reduction activities. Furthermore, there have been limitations in the amount of data about drug use which can be collected due to restrictions. To goal of this study was to obtain information about potential changes in illicit drug use impacted by COVID-19 restrictions. Wastewater samples were collected in seven cities in the Netherlands, Belgium, Spain and Italy at the beginning of lockdowns (March-May 2020). Using previously established and validated methods, levels of amphetamine (AMP), methamphetamine (METH), MDMA, benzoylecgonine (BE, the main metabolite of cocaine) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH, main metabolite of tetrahydrocannabinol (THC)) were measured and compared with findings from previous years. Important differences in levels of consumed drugs were observed across the considered countries. Whilst for some substances and locations, marked decreases in consumption could be observed (e.g., 50% decrease in MDMA levels compared to previous years). In some cases, similar or even higher levels compared to previous years could be found. Changes in weekly patterns were also observed, however these were not clearly defined for all locations and/or substances. Findings confirm that the current situation is highly heterogeneous and that it remains very difficult to explain and/or predict the effect that the present pandemic has on illicit drug use and availability. However, given the current difficulty in obtaining data due to restrictions, wastewater analysis can provide relevant information about the situation at the local level, which would be hard to obtain otherwise.


Assuntos
COVID-19 , Drogas Ilícitas , Transtornos Relacionados ao Uso de Substâncias , Poluentes Químicos da Água , Bélgica , Cidades , Controle de Doenças Transmissíveis , Humanos , Itália , Países Baixos , SARS-CoV-2 , Espanha , Detecção do Abuso de Substâncias , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Águas Residuárias/análise , Poluentes Químicos da Água/análise
16.
J Fish Biol ; 98(1): 33-43, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32964414

RESUMO

Movement is a fundamental aspect of fish ecology, and it therefore represents an important trait to monitor for the management and conservation of fish populations. This is especially true for small benthic fish, as they often inhabit part of the catchment where their movement may be restricted by alterations to river connectivity due to human activity. Still, the movement of these small benthic fish remains poorly understood, partly because of their small size and their cryptic nature. This applies to Percilia irwini, an endangered small darter native to the south-central region of Chile. Its habitat has been affected by the presence of large hydroelectric dams and is currently threatened by the construction of several others. In this study, the authors investigated movement patterns of P. irwini from populations inhabiting different parts of the Biobío catchment, with different levels of connectivity due to natural and/or human-induced features. The authors combined chronological clustering with random forest classification to reconstruct lifelong movements from multi-elemental otolith microchemistry transects. The majority of the movements detected occurred in an undisturbed part of the catchment. These were directional upstream movements occurring between capture sites from the lower and the middle reaches of the river, representing a distance of nearly 30 km, a distance much larger than previously thought. Nonetheless, in the part of the catchment where connectivity was affected by human activity, no such movements were identified. This study shows that connectivity alteration could impede naturally occurring movement and further threaten the resilience of populations of P. irwini. Furthermore, the results presented are used to discuss advantages and disadvantages of microchemistry analysis for studying movement of small benthic fish.


Assuntos
Migração Animal/fisiologia , Espécies em Perigo de Extinção , Perciformes/fisiologia , Rios , Animais , Chile , Ecossistema , Membrana dos Otólitos/química
17.
Sci Total Environ ; 738: 139352, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32806381

RESUMO

Roads are estimated to be the largest source of microplastic particles in the environment, through release of particles from tires, road markings and polymer-modified bitumen. These are all released through the wear and tear of tires and the road surface. During the winter in cold climates, the road surface may freeze and cause icing on the roads. To improve traffic safety during winter, road salt is used for de-icing. Knowledge of microplastic (MP) contamination in road salt has, until now, been lacking. This is contrary to the increasing number of studies of microplastics in food-grade salt. The objective of this study was to investigate if road salt could be an additional source of microplastics to the environment. Fourier-Transform Infrared spectroscopy (FT-IR) and Pyrolysis gas chromatography mass spectrometry (GC-MS) were employed to identify and quantify the polymer content in four types of road salts, three sea salts and one rock salt. The particle number of MP in sea salts (range 4-240 MP/kg, mean ±â€¯s.d. = 35 ±â€¯60 MP/kg) and rock salt (range 4-192 MP/kg, 424 ±â€¯61 MP/kg, respectively) were similar, whereas, MP mass concentrations were higher in sea salts (range 0.1-7650 µg/kg, 442 ±â€¯1466 µg/kg) than in rock salts (1-1100 µg/kg, 322 ±â€¯481 µg/kg). Black rubber-like particles constituted 96% of the total concentration of microplastics and 86% of all particles in terms of number of particles/kg. Black rubber-like particles appeared to be attributable to wear of conveyer belts used in the salt production. Road salt contribution to MP on state and county roads in Norway was estimated to 0.15 t/year (0.003% of total road MP release), 0.07 t/year in Sweden (0.008%) and 0.03 t/year in Denmark (0.0004-0.0008%) Thus, microplastics in road salt are a negligible source of microplastics from roads compared to other sources.

18.
Am J Clin Nutr ; 112(4): 1039-1050, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32844187

RESUMO

BACKGROUND: Maternal micronutrient deficits during preconception and pregnancy may persist during lactation and compromise human milk composition. OBJECTIVE: We measured micronutrient concentrations in human milk and investigated their association with maternal micronutrient intakes, status, and milk volume. METHODS: Infant milk intake (measured via a deuterium dose-to-mother technique), milk micronutrient and fat concentrations, and maternal micronutrient intakes were assessed at 2 and 5 mo postpartum in 212 Indonesian lactating mother-infant pairs. Maternal hemoglobin, ferritin, transferrin receptors, retinol binding protein (RBP), zinc, selenium, and vitamin B-12 were measured at 5 mo (n = 163). Multivariate or mixed effects regression examined associations of milk micronutrient concentrations with maternal micronutrient intakes, status, and milk volume. RESULTS: Prevalence of anemia (15%), and iron (15% based on body iron), selenium (2.5%), and vitamin B-12 deficiency (0%) were low compared with deficiencies of zinc (60%) and vitamin A (34%). The prevalence of inadequate intakes was >50% for 7 micronutrients at 2 and 5 mo. Median milk concentrations for most micronutrients were below reference values, and nearly all declined between 2 and 5 mo postpartum and were not associated substantially with milk volume (except for ß-carotene, α-carotene, and ß-cryptoxanthin). At 5 mo postpartum, associations between maternal micronutrient status and corresponding milk concentrations reported as mean percentage difference in human milk concentration for each unit higher maternal biomarker were significant for hemoglobin (1.9%), iron biomarkers (ranging from 0.4 to 7%), RBP (35%), selenium (70%), and vitamin B-12 (0.1%), yet for maternal intakes only a positive association with ß-carotene existed. CONCLUSIONS: Most milk micronutrient concentrations declined during lactation, independent of changes in human milk production, and few were associated with maternal micronutrient intakes. The significant associations between maternal biomarkers and milk micronutrient concentrations at 5 mo warrant further study to investigate whether the declines in milk micronutrients are linked to shifts in maternal status.


Assuntos
Dieta , Micronutrientes/análise , Leite Humano/química , Período Pós-Parto/metabolismo , Adulto , Feminino , Humanos , Micronutrientes/administração & dosagem , Gravidez
19.
Foods ; 9(8)2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32784633

RESUMO

This study assessed the effect of cow milk (CM) and sheep milk (SM) consumption on the micro-structure, mechanical function, and mineral composition of rat femora in a male weanling rat model. Male weanling rats were fed a basal diet with a 50% reduction in calcium and phosphorus content (low Ca/P-diet) supplemented with either SM or CM. Rats were fed for 28 days, after which the femora were harvested and stored. The femora were analyzed by µ-CT, three-point bending, and inductively coupled plasma-mass spectrometry (ICP-MS). The addition of either milk to the low Ca/P-diet significantly increased (p < 0.05) trabecular bone volume, trabecular bone surface density, trabecular number, cortical bone volume, and maximum force, when compared to rats that consumed only the low Ca/P-diet. The consumption of either milk resulted in a significant decrease (p < 0.05) in trabecular pattern factor, and cortical bone surface to volume ratio when compared to rats that consumed only the low Ca/P-diet. The results were achieved with a lower consumption of SM compared to that of CM (p < 0.05). This work indicates that SM and CM can help overcome the effects on bone of a restriction in calcium and phosphorus intake.

20.
Sci Total Environ ; 723: 138132, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32222514

RESUMO

Pesticides offer many benefits for humanity and agriculture, but at the same time pose a potential risk to human health because of their widespread use and high biological activity. Human biomonitoring (HBM) studies are the main tool to investigate human exposure to pesticides and other chemicals, but face limitations such as sampling biases, long time to complete and high costs. Wastewater-based epidemiology (WBE) is an alternative approach that is centered on the chemical analysis of biomarkers of (pesticide) exposure in urban wastewater. The present study used WBE to assess human exposure to selected classes of pesticides, triazines, pyrethroids and organophosphates, in Norway. Untreated wastewater samples were collected from four cities, covering approximately 20% of the Norwegian population. The highest population weighted mass loads (mg/day/1000 inhabitants) were for alkyl phosphates and the lowest for triazines. Some differences were observed for the two metabolites, 2-isopropyl-6-methyl-4-pyrimidinol (IMPY) and 3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (DCCA), which were higher in the rural city of Hamar. WBE figures were comparable with HBM findings for the specific metabolite of chlorpyrifos and chlorpyrifos methyl (3,5,6-trichloro-2-pyridinol; TCPY) but were different for the alkyl phosphates. Pyrethroid intake was calculated and was lower than the acceptable daily intake in all the cities, indicating low risk for human health. This is the most extensive WBE study performed to date to assess national human exposure to pesticides. This study demonstrated that WBE has the potential to be a useful complementary biomonitoring tool for assessing population-wide exposure to pesticides, overcoming some of the limitations of HBM.


Assuntos
Praguicidas/análise , Piretrinas , Cidades , Exposição Ambiental/análise , Humanos , Noruega , Águas Residuárias/análise
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