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Deformed wing virus (DWV) is a honey bee virus, whose emergence from relative obscurity is driven by the recent host-switch, adaptation, and global dispersal of the ectoparasitic mite Varroa destructor (a highly efficient vector of DWV) to reproduction on honey bees (Apis mellifera). Our study examines how varroa affects the continuing evolution of DWV, using the Azores archipelago, where varroa is present on only three out of the eight Islands, as a natural experimental system for comparing different evolutionary conditions and trajectories. We combined qPCR of 494 honey bee colonies sampled across the archipelago with amplicon deep sequencing to reveal how the DWV genetic landscape is altered by varroa. Two of the varroa-free Islands were also free of DWV, while a further two Islands were intriguingly dominated by the rare DWV-C major variant. The other four Islands, including the three varroa-infested Islands, were dominated by the common DWV-A and DWV-B variants. The varroa-infested Islands had, as expected, an elevated DWV prevalence relative to the uninfested Islands, but not elevated DWV loads, due the relatively high prevalence and loads of DWV-C on the varroa-free Islands. This establishes the Azores as a stable refuge for DWV-C and provides the most convincing evidence to date that at least some major strains of DWV may be capable of not just surviving, but actually thriving in honey bees in the absence of varroa-mediated transmission. We did not detect any change in DWV genetic diversity associated with island varroa status but did find a positive association of DWV diversity with virus load, irrespective of island varroa status.
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Pigeonpea [Cajanus cajan (L.) Millspaugh] is a widely grown pulse with high seed protein content that contributes to food and nutritional security in the Indian subcontinent. The majority of pigeonpea varieties cultivated in India are of medium duration (<180 days to maturity), which makes it essential for breeders to focus on the development of stable high-yielding varieties. The diverse agroecological regime in the Indian subcontinent necessitates an efficient multi-environment study by taking into consideration genotype (G) × environment (E) interaction (GEI) that has a significant impact on traits like grain yield (GY) in developing high-yielding and widely adaptable varieties. In the present study, 37 pigeonpea genotypes were evaluated during the 2021 rainy season at ARS Badnapur, ARS Tandur, BAU Ranchi, GKVK Bengaluru, and ICRISAT Patancheru. The GEI was significant on the grain yield (p < 0.01), and hence, genotype + genotype × environment (GGE) and additive main effects and multiplicative interaction (AMMI) biplots along with AMMI stability value (ASV) and yield relative to environmental maximum (YREM) statistics were used to identify stable high-yielding genotypes. The interaction principal component analysis 1 and 2 (IPC1 and IPC2) explained 40.6% and 23.3% variations, respectively. Based on the rankings of genotypes, G37 (ICPL 20205), G35 (ICPL 20203), G8 (ICPL 19404), G17 (ICPL 19415), and G9 (ICPL 19405) were identified as ideal genotypes. Discriminativeness vs. representativeness identified GKVK Bengaluru as an ideal environment for comprehensive evaluation of test genotypes. However, ICPL 19405 was identified as the potentially stable high-yielding genotype for further testing and release across the test environments based on its mean grain yield (1,469.30 kg/ha), least ASV (3.82), and low yield stability index (YSI) of 13.
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This dataset offers a comprehensive analysis of rice grain yield and quality traits over a period of three years, spanning 27 different environments in Bangladesh. The focus is on evaluating the performance of various genotypes (G), environments (E), and their interactions (GEI). The study's goal is to identify a stable and adaptive rice genotype that not only exhibits high-quality traits but also has a low glycemic index. The combined ANOVA showed significant effects of G, E, and GEI on grain yield (p ≤ 0.001). Genotype BRC266-5-1-1-1 achieved the highest average yield at 7.62 t/ha, while BRRI dhan28 had the lowest yield at 6.87 t/ha. In the Y2E4 environment, genotype BRC266-5-1-1-1 reached the highest yield at 8.86 t/ha. Genetic parameter estimation revealed significant effects of G, E, and GEI (p < 0.05), with GEI accounting for 82.85 % of the variance. The broad-sense heritability was low at 12 %, but the heritability of means was 0.80, indicating high selection accuracy (0.89). AMMI analysis showed significant effects from E (62.62 %) and GEI (16.19 %), with the first two principal components explaining 100 % of the variance. AMMI-based stability analysis identified BRC266-5-1-1-1 as the most stable genotype, with the highest AMMI-based stability parameter (ASTAB) at 2.11 and AMMI stability value (ASV) at 3.04. GGE biplot analysis revealed that BRC266-5-1-1-1 performed best in 14 environments. Quality trait analysis showed that BR16 and BRC266-5-1-1-1 had the highest milling outturn (70.90 %), with BRC266-5-1-1-1 also having the highest head rice yield (66.5 %). BRRIdhan28 had the highest glycemic index value (GIV) at 75.7, followed by BRC266-5-1-1-1 (55.04). These findings emphasize the significance of choosing appropriate genotypes for varietal release and taking environmental factors into account in rice breeding programs.
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Widely-used C60 fullerene nanoparticles (C60) result in their release into the aquatic environment, which may affect the distribution and toxicity of pollutants such as arsenic (As), to aquatic organism. In this study, arsenate (As(V)) accumulation, speciation and subcellular distribution was determined in Danio rerio (zebrafish) intestine, head and muscle tissues in the presence of C60. Meanwhile we compared how single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), graphene oxide (GO) and graphene (GN) nanoparticles alter the behaviors of As(V). Results showed that C60 significantly inhibited As accumulation and toxicity in D. rerio, due to a decrease in total As and monomethylarsonic acid (MMA) and As(V) species concentrations, a lower relative distribution in the metal-sensitive fraction (MSF). It was attributed that C60 may coat As(V) ion channels and consequently, affect the secretion of digestive enzymes in the gut, favoring As excretion and inhibiting As methylation. Similarly, MWCNTs reduced the species concentration of MMA and As(V) in the intestines, low GSH (glutathione) contents in the intestine. Due to the disparity of other carbon-based nanomaterial morphologies, SWCNTs, GO and GN exhibited the various effects on the toxicity of As(V). In addition, the possible pathway of arsenobetaine (AsB) biosynthesis included migration from the intestine to muscle in D. rerio, with the precursor of AsB likely to be 2-dimethylarsinylacetic acid (DMAA). The results of this study suggest that C60 is beneficial for controlling As(V) pollution and reducing the impact of As(V) biogeochemical cycles throughout the ecosystem.
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Arseniatos , Fulerenos , Nanopartículas , Contaminantes Químicos del Agua , Pez Cebra , Fulerenos/toxicidad , Animales , Arseniatos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Nanopartículas/toxicidad , Nanotubos de Carbono/toxicidad , Grafito/toxicidadRESUMEN
BACKGROUND: One single-center randomized clinical trial showed that INTELLiVENT-adaptive support ventilation (ASV) is superior to conventional ventilation with respect to the quality of ventilation in post-cardiac surgery patients. Other studies showed that this automated ventilation mode reduces the number of manual interventions at the ventilator in various types of critically ill patients. In this multicenter study in patients post-cardiac surgery, we test the hypothesis that INTELLiVENT-ASV is superior to conventional ventilation with respect to the quality of ventilation. METHODS: "POStoperative INTELLiVENT-adaptive support VEntilation in cardiac surgery patients II (POSITiVE II)" is an international, multicenter, two-group randomized clinical superiority trial. In total, 328 cardiac surgery patients will be randomized. Investigators screen patients aged > 18 years of age, scheduled for elective cardiac surgery, and expected to receive postoperative ventilation in the ICU for longer than 2 h. Patients either receive automated ventilation by means of INTELLiVENT-ASV or ventilation that is not automated by means of a conventional ventilation mode. The primary endpoint is quality of ventilation, defined as the proportion of postoperative ventilation time characterized by exposure to predefined optimal, acceptable, and critical (injurious) ventilatory parameters in the first two postoperative hours. One major secondary endpoint is ICU team staff workload, captured by the ventilator software collecting manual settings on alarms. Patient-centered endpoints include duration of postoperative ventilation and length of stay in ICU. DISCUSSION: POSITiVE II is the first international, multicenter, randomized clinical trial designed to confirm that POStoperative INTELLiVENT-ASV is superior to non-automated conventional ventilation and secondary to determine if this closed-loop ventilation mode reduces ICU team staff workload. The results of POSITiVE II will support intensive care teams in their choices regarding the use of automated ventilation in postoperative care of uncomplicated cardiac surgery patients. TRIAL REGISTRATION: Clinicaltrials.gov NCT06178510 . Registered on December 4, 2023.
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Procedimientos Quirúrgicos Cardíacos , Estudios Multicéntricos como Asunto , Humanos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Respiración Artificial/métodos , Resultado del Tratamiento , Cuidados Posoperatorios/métodos , Factores de Tiempo , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios de Equivalencia como Asunto , Unidades de Cuidados IntensivosRESUMEN
There is a lack of understanding about the bacterial, fungal and archaeal communities' composition of solid-phase denitrification (SPD) systems. We investigated four SPD systems with different carbon sources by analyzing microbial gene sequences based on operational taxonomic unit (OTU) and amplicon sequence variant (ASV). The results showed that the corncob-polyvinyl alcohol sodium alginate-polycaprolactone (CPSP, 0.86±0.04 mg NO3--N/(g·day)) and corncob (0.85±0.06 mg NO3--N/(g·day)) had better denitrification efficiency than polycaprolactone (PCL, 0.29±0.11 mg NO3--N/(g·day)) and polyvinyl alcohol-sodium alginate (PVA-SA, 0.24±0.07 mg NO3--N/(g·day)). The bacterial, fungal and archaeal microbial composition was significantly different among carbon source types such as Proteobacteria in PCL (OTU: 83.72%, ASV: 82.49%) and Rozellomycota in PVA-SA (OTU: 71.99%, ASV: 81.30%). ASV methods can read more microbial units than that of OTU and exhibit higher alpha diversity and classify some species that had not been identified by OTU such as Nanoarchaeota phylum, unclassified_ f_ Xanthobacteraceae genus, etc., indicating ASV may be more conducive to understand SPD microbial communities. The co-occurring network showed some correlation between the bacteria fungi and archaea species, indicating different species may collaborate in SPD systems. Similar KEGG function prediction results were obtained in two bioinformatic methods generally and some fungi and archaea functions should not be ignored in SPD systems. These results may be beneficial for understanding microbial communities in SPD systems.
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Bacterias , Carbono , Desnitrificación , Microbiota , Bacterias/metabolismo , Bacterias/clasificación , Bacterias/genética , Carbono/metabolismo , Archaea/genética , Archaea/metabolismo , Hongos/metabolismoRESUMEN
Sleep-disordered breathing (SDB), including obstructive and central sleep apnea, significantly exacerbates heart failure (HF) through adverse cardiovascular mechanisms. This review aims to synthesize existing literature to clarify the relationship between SDB and HF, focusing on the pathophysiological mechanisms, diagnostic challenges, and the effectiveness of treatment modalities like continuous positive airway pressure (CPAP) and adaptive servo-ventilation ASV. We analyzed peer-reviewed articles from 2003 to 2024 sourced from PubMed, EMBASE, Scopus, and Web of Science databases. The prevalence of SDB in HF patients is high, often underdiagnosed, and underappreciated. Management strategies, including CPAP and ASV, have been shown to mitigate symptoms and improve cardiac function. However, despite the availability of effective treatments, significant challenges in screening and diagnosis persist, affecting patient management and outcomes. DB significantly impacts HF prognosis. Enhanced screening strategies and broader utilization of therapeutic interventions like CPAP and ASV are essential to improve the management and outcomes of HF patients with concomitant SDB. Future research should focus on refining diagnostic and treatment protocols to optimize care for HF patients with SDB.
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Presión de las Vías Aéreas Positiva Contínua , Insuficiencia Cardíaca , Síndromes de la Apnea del Sueño , Humanos , Insuficiencia Cardíaca/terapia , Síndromes de la Apnea del Sueño/terapia , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/diagnóstico , PronósticoRESUMEN
Arsenic release and reduction in anoxic environments can be mitigated or facilitated by biochar amendment. However, the key fractions in biochars and how they control arsenic transformation remain poorly understood. In this study, a biochar produced from pomelo peel was rich in colloids and was used to evaluate the roles of the colloidal and residual fractions of biochar in arsenic transformation in anoxic paddy soil. Bulk biochar showed a markedly higher maximum adsorption capacity for As(III) at 1732 mg/kg than for As(V) at 75.7 mg/kg, mainly because of the colloidal fraction on the surface. When compared with the control and treatments with the colloidal/residual fraction, the addition of bulk biochar facilitated As(V) reduction and release in the soil during days 0-12, but decreased the dissolved As(III) concentration during days 12-20. The colloidal fraction revealed significantly higher electron donating capacity (8.26 µmole-/g) than that of bulk biochar (0.88 µmole-/g) and residual fraction (0.65 µmole-/g), acting as electron shuttle to promote As(V) reduction. Because the colloidal fraction was rich in aliphatic carbon, fulvic acid-like compounds, potassium, and calcium, it favored As(III) adsorption when more As(III) was released, probably via organic-cation-As(III) complexation. These findings provide deeper insight into the role of the colloidal fraction of biochar in controlling anaerobic arsenic transformation, which will be helpful for the practical application of biochar in arsenic-contaminated environments.
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Arsénico , Carbón Orgánico , Contaminantes del Suelo , Suelo , Carbón Orgánico/química , Arsénico/análisis , Adsorción , Suelo/química , Coloides/química , Citrus/química , Restauración y Remediación Ambiental/métodosRESUMEN
Schwertmannite has attracted increasing interest for its excellent sorption of oxyanions such as AsO43-, CrO42-, and Sb(OH)6-. Controlling biomineralization by adjusting the Fe(II) oxidation rate and implementing alkali control can enhance the yield and adsorption performance of schwertmannite. However, the adsorption improvement mechanism is still unclear. The morphology, crystallinity, specific surface area (SSA) and oxyanion adsorption of schwertmannite synthesized with alkali control of solution pH and different Fe(II) oxidation rates were analyzed in this study. The differences in the adsorption mechanisms of As(V), Cr(VI) and Sb(V) on schwertmannite obtained under different synthesis conditions were also studied. Reducing the Fe(II) oxidation rate or maintaining the solution pH through alkali control significantly increased the SSA of schwertmannite and the proportion of outer-sphere sulfate. Alkali-controlled schwertmannite (Sch-C) exhibited superior As(V) and Sb(V) adsorption performance and slightly greater Cr(VI) adsorption than non-alkali-controlled schwertmannite. The As(V) and Sb(V) adsorption capacities of Sch-C greatly improved because the ultra-high SSA increased the surface hydroxyl content and reduced the passivation effect of amorphous precipitates on the mineral surface, allowing continuous sulfate exchange at inner mineral sites. An increased surface hydroxyl content had little effect on Cr(VI) adsorption, but an increased proportion of outer-sphere sulfate caused a slight increase in Cr(VI) adsorption. Sb(V) has a stronger hydroxyl exchange ability than As(V), but due to its octahedral structure, it exchanges only with outer-sphere sulfate on schwertmannite and hardly exchanges with inner-sphere sulfate.
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The high cost and low adsorption capacity of primary metal-organic frameworks (ZIF-8) limit their application in heavy metal removal. In this paper, Co/Zn bimetallic MOF materials were synthesized with excellent adsorption performance for As5+. The adsorption reached equilibrium after 180 min and the maximum adsorption was 250.088 mg/g. In addition, Co-ZIF-8 showed strong selective adsorption of As5+. The adsorption process model of Co-ZIF-8 fits well with the pseudo-second-order kinetic model (R2=0.997) and Langmuir isotherm model (R2=0.994), and it is demonstrated that the adsorption behavior of the adsorbent is a single layer of chemical adsorption. In addition, when the adsorbent enters the arsenic-containing solution, the surface of Co-ZIF-8 is hydrolyzed to produce a large number of Co-OH active sites, and As5+ arrives at the surface of Co-ZIF-8 by electrostatic adsorption and combines with the active sites to generate the arsenic-containing complex As-O-Co. After four cycles, Co-ZIF-8 showed 80% adsorption of As5+. This study not only provides a new method to capture As5+ in water by preparing MOF with partial replacement of the central metal, but also has great significance for the harmless disposal of polluted water.
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Arsénico , Cobalto , Estructuras Metalorgánicas , Aguas Residuales , Contaminantes Químicos del Agua , Adsorción , Arsénico/química , Cobalto/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Estructuras Metalorgánicas/química , Cinética , Purificación del Agua/métodosRESUMEN
For the autonomous surface vehicle (ASV) planning problem, an enhanced A* method incorporating encrypted memory database for ASV efficient local path planning is proposed. Considering the current various path planning problems mostly use methods with high time complexity, such as neural networks, we select the A* algorithm with low time complexity as the basis. To speed up the path planning rate and further improve the real-time and realistic algorithm, this paper modifies the heuristic function of the A* algorithm by combining the motion mode of ASV. In response to the problem that the target point is far from the detection, we improve the target point design mechanism and create a new temporary target point within the detection range. In addition, the algorithm incorporates a memory database, which can record commonly used waters or retain the environmental path of navigated waters as a priori information. When the same waters are reencountered, the memory database information can be read directly to complete the navigation. Moreover, the memory database is encrypted to prevent information leakage. Finally, a simulation environment is built to verify the effectiveness of the proposed algorithm by comparison with some existing algorithms.
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Arsenic (As) contaminated water, especially groundwater reservoirs, is a major issue worldwide owing to its hazardous consequences on human health and the global environment issues. Also, irrigating agricultural fields with As-contaminated water not only produces an accumulation of As in the soil but also compromises food safety due to As entering into agricultural products. Hence, there is an urgent need to develop an efficient method for As removal in water. Fe-based MOFs have attained special attention due to their low toxicity, high water stability, better physical and chemical properties, and high abundance of iron. The arsenic species removal by Fe-MOF follows the adsorption and oxidation mechanism where As (III) converts into As (V). Moreover, the adsorption mechanism is facilitated by electrostatic interactions, H-bonding, acid-base interaction, hydrophobic interactions, van der Waals forces, π-π stacking interactions, and coordinative bindings responsible for Fe-O-As bond generation. This review thoroughly recapitulates and analyses recent advancements in the facile synthesis and potential application of Fe-based MOF adsorbents for the elimination of As ions. The most commonly employed hydro/solvothermal, ultrasonic, microwave-assisted, mechanochemical, and electrochemical synthesis for Fe-MOF has been discussed along with their adsorptive and oxidative mechanisms involved in arsenic removal. The effects of factors like pH and coexisting ions have also been discussed. Lastly, the article also proposed the prospects for developing the application of Fe-based MOF in treating As-contaminated water.
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Arsénico , Hierro , Estructuras Metalorgánicas , Contaminantes Químicos del Agua , Purificación del Agua , Arsénico/química , Arsénico/análisis , Adsorción , Contaminantes Químicos del Agua/química , Hierro/química , Purificación del Agua/métodos , Estructuras Metalorgánicas/química , Catálisis , Oxidación-Reducción , Agua Subterránea/químicaRESUMEN
As(V)-loaded granular activated carbon was regenerated through electrocoagulation assisted by elution with NaCl. Adsorption of As(V) by activated carbon was highest at pH 6, and subsequent desorption in water was highest at pH 11, followed by pH 3. Lower initial pH improved arsenic removal during electrocoagulation, NaCl concentration was insignificant, but removal increased with current density. Adding Fe(II) before electrocoagulation led to an improved removal efficiency up to a concentration of 30 mg/L. Regeneration of As(V)-loaded activated carbon increased with current density and time up to a maximum of 85%. An increase in NaCl concentration to 6000 mg/L further improved regeneration to 92%. Regeneration at a lower current density only dropped slightly from 54% to 51% when doubling activated carbon concentration, demonstrating excellent scalability. Repeated adsorption-desorption tests were performed, where 81% and 69% regeneration were obtained after four regenerations with NaCl concentrations of 6000 and 750 mg/L, respectively. NaCl concentration in the tested range did not influence electrocoagulation but improved regeneration through elution. The combination of electrocoagulation and elution facilitated a higher regeneration efficiency, meanwhile removing As(V) from the solution through adsorption on iron hydroxide. PRACTITIONER POINTS: As(V)-loaded activated carbon was regenerated by electrocoagulation with elution. Regeneration increased with regeneration time and current density up to 85%. Addition of 6000 mg/L NaCl further increased regeneration to 93%. Regeneration of 82% was achieved after four regenerations. NaCl did not affect electrocoagulation but improved regeneration through elution.
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Arsénico , Contaminantes Químicos del Agua , Purificación del Agua , Carbón Orgánico , Cloruro de Sodio , Concentración de Iones de Hidrógeno , Electrocoagulación , AdsorciónRESUMEN
Graphene (GR) is a new type of carbon-based material that combines many excellent properties. In order to give full play to the excellent properties of graphene and expand its application scope, this study used ionic liquid SbF6 to modify it and successfully prepared ionic liquid modified graphene composites (H/GR), and studied its adsorption mechanism of arsenic in aqueous solution. By investigating the effects of reaction temperature, reaction time, pH, adsorbent (H/GR) dosage, and humic acid concentration on the removal rate of arsenic in aqueous solution, the experimental results showed that when the reaction temperature was 30 °C, reaction time was 1 h, pH was 6, H/GR dosage was 0.1g·L-1, and humic acid (HA) concentration was 10 mg·L-1, the best arsenic removal effect was achieved with a maximum. The removal rate was 99.4%. The equilibrium adsorption capacity was well modeled by the Langmuir, Freundlich, and Tenkin models at 30 °C. The Langmuir adsorption isotherm was the most consistent, with a calculated maximum value of 137.95 mg·g-1, which is higher than most adsorbents in the field. In addition, it was determined that the graphene surface was indeed immobilized with the ionic liquid [Hmim]SbF6 by SEM mapping and EDS energy spectroscopy observation, and the adsorption isotherms and pore size distribution maps of graphene before and after the loading of the ionic liquid were analyzed by BET, which further confirmed a significant increase in the microporosity and porosity of the modified H/GR, and furthermore, it was demonstrated that the arsenic ions are chemically bonded with and indeed adsorbed on the surface of the H/GR by FT-IR and XPS characterization analyses. The results of all experimental data studies indicate that the main mechanism of As(V) removal from water by H/GR is due to electrostatic adsorption, ion exchange, and complexation between the modified graphene itself and the ionic liquid [Hmim]SbF6 itself.
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Arsénico , Grafito , Líquidos Iónicos , Contaminantes Químicos del Agua , Arsénico/análisis , Grafito/química , Líquidos Iónicos/análisis , Adsorción , Espectroscopía Infrarroja por Transformada de Fourier , Sustancias Húmicas/análisis , Agua , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , CinéticaRESUMEN
The Black Sea is a unique environment with strong and permanent vertical stratification, with a thin layer of oxic zone above and a permanent anoxic zone below. Few high-throughput genomic surveys have been conducted to examine microbiota in the Black Sea. Yet, there is no study on the seasonal and vertical variation in microbial community compositions, driving forces and mechanisms of community assembly. In this study, seasonal, vertical, and spatial microbial assemblages were studied in terms of diversity, abundance, and community structure using 16S rRNA metabarcoding. 16S rRNA metabarcoding confirmed seasonal changes in microbial communities and the presence of distinct microbial groups among different water layers. Taxa belonging to Cyanobiaceae contributed a large fraction of the total biomass and were the most abundant autotrophic bacteria found across the whole water column, including hydrogen sulfide-containing anoxic zone. Temperature, salinity, water density, conductivity, light, chlorophyll-a, O2, NO3, NH3, PO4, Si, and H2S had a significant influence on the vertical bacterial community assemblages. The copper mine discharge system at 180 m did not affect microbial community structure and composition. Temperature seemed to be a primary factor in the variance between shallow depths. In conclusion, the lack of light, low dissolved oxygen levels, and low temperature do not restrict microbial diversity, as proven by the higher diversity observed in deeper zones. Wastewater in Black Sea region may be discharged into the Black Sea to depth of 180 m or deeper without impacting microbial ecology.
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Microbiota , Agua de Mar , Agua de Mar/química , ARN Ribosómico 16S/genética , Mar Negro , Bacterias/genética , AguaRESUMEN
Although sodium alginate (SA) is frequently utilized because of its good gelling properties, the substance's dearth of adsorption active sites prevents it from effectively removing heavy metals. Herein, SA was used as the base material to form a cross-linked structure with Fe3+ and Mg2+, and gel beads with a diameter of 2.0 ± 0.1 mm with specific adsorption on As(V) were synthesized as adsorbent (Fe/Mg-SA). Fe/Mg-SA was systematically characterized, and its adsorption properties were investigated by varying several conditions. Fe/Mg-SA had a wide pH application range. The adsorption kinetics revealed that a quasi-secondary kinetic model was followed. The adsorption process is linked to the complexation of hydroxyl and AsO43-, chemisorption predominated the adsorption process. The maximal adsorption capacity of Fe/Mg-SA is determined by fitting the Langmuir model to be 37.4 mg/g. Compared to other adsorbents, it is simpler to synthesis, more effective and cheaper. Each treatment of 1 m3 wastewater of Fe/Mg-SA only costs ¥ 38.612. The novel gel beads synthesized provides a better option for purifying groundwater contaminated with As(V).
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Metales Pesados , Contaminantes Químicos del Agua , Alginatos/química , Adsorción , Porosidad , Metales Pesados/química , Geles/química , Cinética , Contaminantes Químicos del Agua/química , Concentración de Iones de HidrógenoRESUMEN
Growth of meat microbiota usually results in spoilage of meat that can be perceived by consumers due to sensory changes. However, a high bacterial load does not necessarily result in sensory deviation of meat; nevertheless, this meat is considered unfit for human consumption. Therefore, the aims of this study were to investigate changes in the microbiota from fresh to spoiled meat and whether the proportions of certain bacteria can probably be used to indicate the hygiene status of meat. For this purpose, 12 fresh pork samples were divided into two groups, and simultaneously aerobically stored at 4°C and 22°C. At each time-temperature point (fresh meat, days 6, 13, and 20 at 4°C, and days 1, 2, 3, and 6 at 22°C), 12 meat subsamples were investigated. Sequences obtained from next-generation sequencing (NGS) were further analyzed down to species level. Plate counting of six bacterial groups and NGS results showed that Pseudomonas spp. and lactic acid bacteria (LAB) were found in a high proportion in all stored meat samples and can therefore be considered as important "spoilage indicator bacteria". On the contrary, sequences belonging to Staphylococcus epidermidis were found in a relatively high proportion in almost all fresh meat samples but were less common in stored meat. In this context, they can be considered as "hygiene indicator bacteria" of meat. Based on these findings, the proportion of the "hygiene indicator bacteria" in relation to the "spoilage indicator bacteria" was calculated to determine a "hygiene index" of meat. This index has a moderate to strong correlation to bacterial loads obtained from culture (p < 0.05), specifically to Pseudomonas spp., LAB and total viable counts (TVCs). Knowledge of the proportions of hygiene and spoilage indicator bacteria obtained by NGS could help to determine the hygiene status even of (heat-) processed composite meat products for the first time, thus enhancing food quality assurance and consumer protection.
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Microbiología de Alimentos , Microbiota , Humanos , ARN Ribosómico 16S/genética , Carne/microbiología , Bacterias , PseudomonasRESUMEN
The taxonomic assignment of sequences obtained by high throughput amplicon sequencing poses a limitation for various applications in the biomedical, environmental, and agricultural fields. Identifications are constrained by the length of the obtained sequences and the computational processes employed to efficiently assign taxonomy. Arriving at a consensus is often preferable to uncertain identification for ecological purposes. To address this issue, a new tool called "ASVmaker" has been developed to facilitate the creation of custom databases, thereby enhancing the precision of specific identifications. ASVmaker is specifically designed to generate reference databases for allocating amplicon sequencing data. It uses publicly available reference data and generates specific sequences derived from the primers used to create amplicon sequencing libraries. This versatile tool can complete taxonomic assignments performed with pre-trained classifiers from the SILVA and UNITE databases. Moreover, it enables the generation of comprehensive reference databases for specific genes in cases where no directly applicable database exists for taxonomic classification tools.
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Due to the different physical and chemical properties such as surface charge and ion morphology between As(V) and Cd(II), it is challenging to remove As(V) and Cd(II), especially at low concentrations. This study constructed a novel three-dimension nanocomposite adsorbent Mg/Al/Fe-CLDH (CFMA) by "hydrothermal + calcination method". And different initial concentration ratios (Cd: As=1: 2, 1: 1, 2: 1) were used to investigate the removal performance of CFMA for Cd(II) and As(V). When the concentration ratio Cd: As=1: 2, the residual concentrations of As(V) and Cd(II) were 8.7 µg/L and 4.2 µg/L, respectively, which met the drinking water standard; In the co-adsorption system, As(V) and Cd(II) influence each other's adsorption behavior due to the anionic bridge and shielding effect of As(V) on Cd(II), As(V) gradually changed from monolayer adsorption to multi-layer adsorption dominant, while Cd(II) gradually changed from multi-layer adsorption to monolayer adsorption dominant. In this paper, the structure-activity relationship between material structure and synchronous removal of arsenic and cadmium was clarified, and the mechanism of synchronous removal was revealed, which provided technical guidance for synchronous removal of As(V) and Cd(II) from non-ferrous metal smelting wastewater.