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1.
Environ Sci Technol ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105779

RESUMEN

Low concentrations of nitrate (NO3-) widely exist in wastewater, post-treated wastewater, and natural environments; its further disposal is a challenge but meaningful for its discharge goals. Electroreduction of NO3- is a promising method that allows to eliminate NO3- and even generate higher-value NH3. However, the massive side reaction of hydrogen evolution has raised great obstacles in the electroreduction of low concentrations of NO3-. Herein, we present an efficient electroreduction method for low or even ultralow concentrations of NO3- via NO3- self-enrichment and active hydrogen (H*) inducement on the Ce(IV)-Co3O4 cathode. The key mechanism is that the strong oxytropism of Ce(IV) in Co3O4 resulted in two changes in structures, including loose nanoporous structures with copious dual adsorption sites of Ce-Co showing strong self-enrichment of NO3- and abundant oxygen vacancies (Ovs) inducing substantial H*. Ultimately, the bifunctional role synergistically promoted the selective conversion of NH3 rather than H2. As a result, Ce(IV)-Co3O4 demonstrated a NO3- self-enrichment with a 4.3-fold up-adsorption, a 7.5-fold enhancement of NH3 Faradic efficiency, and a 93.1% diminution of energy consumption when compared to Co3O4, substantially exceeding other reported electroreduction cathodes for NO3- concentrations lower than 100 mg·L-1. This work provides an effective treatment method for low or even ultralow concentrations of NO3-.

2.
Compr Rev Food Sci Food Saf ; 23(4): e13399, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39072953

RESUMEN

Milk, as a widely consumed nutrient-rich food, is crucial for bone health, growth, and overall nutrition. The persistent application of veterinary drugs for controlling diseases and heightening milk yield has imparted substantial repercussions on human health and environmental ecosystems. Due to the high demand, fresh consumption, complex composition of milk, and the potential adverse impacts of drug residues, advanced greener analytical methods are necessitated. Among them, functional materials-based analytical methods attract wide concerns. The magnetic molecularly imprinted polymers (MMIPs), as a kind of typical functional material, possess excellent greenification characteristics and potencies, and they are easily integrated into various detection technologies, which have offered green approaches toward analytes such as veterinary drugs in milk. Despite their increasing applications and great potential, MMIPs' use in dairy matrices remains underexplored, especially regarding ecological sustainability. This work reviews recent advances in MMIPs' synthesis and application as efficient sorbents for veterinary drug extraction in milk followed by chromatographic analysis. The uniqueness and effectiveness of MMIPs in real milk samples are evaluated, current limitations are addressed, and greenification opportunities are proposed. MMIPs show promise in revolutionizing green analytical procedures for veterinary drug detection, aligning with the environmental goals of modern food production systems.


Asunto(s)
Residuos de Medicamentos , Tecnología Química Verde , Leche , Polímeros Impresos Molecularmente , Drogas Veterinarias , Leche/química , Residuos de Medicamentos/análisis , Residuos de Medicamentos/química , Polímeros Impresos Molecularmente/química , Animales , Drogas Veterinarias/análisis , Drogas Veterinarias/química , Tecnología Química Verde/métodos , Contaminación de Alimentos/análisis , Impresión Molecular/métodos , Cromatografía/métodos
3.
Sci Rep ; 14(1): 16054, 2024 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992077

RESUMEN

To explore the related factors of turnover intention in clinical research coordinators (CRCs) and assess the mediating effects of professional identity on the association between job burnout and turnover intention. In China, CRC has become increasingly common among clinical trial teams in recent years. However, limited published research focused on the status of turnover intention in CRCs. We invited all the 220 CRCs currently working at Hunan Cancer Hospital located in Changsha city in the central south of China from March to June 2018. Participants were asked to complete structured questionnaires regarding basic demographic information, job burnout, professional identity and turnover intention. A total of 202 participants were included in this study, with a response rate of 91.82%. The main reason for turnover intention among CRCs was human resources, followed by communications, management and material resources (per item score in each dimension: 2.14 vs. 2.43 vs. 2.65 vs. 2.83). All the correlations among job burnout, professional identity and turnover intention were statistically significant, with coefficients ranging from -0.197 to 0.615. Multiple liner regression analysis showed that older age, longer workhours per week, and lower level of professional identity were associated with the prevalence of turnover intention among CRCs. Besides, the association between job burnout and turnover intention was fully mediated by professional identity. This study revealed the status and causes of turnover intention among Chinese CRCs. Effective measures on decreasing working time and improving professional identity should be taken in order to reduce CRCs' turnover intention.


Asunto(s)
Agotamiento Profesional , Reorganización del Personal , Humanos , Reorganización del Personal/estadística & datos numéricos , China/epidemiología , Masculino , Femenino , Estudios Transversales , Agotamiento Profesional/epidemiología , Agotamiento Profesional/psicología , Adulto , Persona de Mediana Edad , Encuestas y Cuestionarios , Investigadores/psicología , Intención , Satisfacción en el Trabajo
4.
Front Genet ; 15: 1375488, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39027886

RESUMEN

Introduction: Bougainvillea glabra "Elizabeth Angus" is a thorny woody vine or shrub. However, the hard thorns are considered a deficiency in its ornamental value. Methods: To find the genes and pathways related to the hardening process of the thorns on the stems of B. glabra, the eukaryotic unreferenced transcriptome sequencing analysis was conducted to explore the 3 stages of the thorn-hardening process. Total RNA was extracted from thorns and stems, and transcriptome libraries were constructed and sequenced using unreferenced Illumina sequencing. Results: Gene function annotation was performed using various databases, resulting in 8937 co-annotated genes. The density distribution of Fragments Per Kilobase of transcript per Million mapped reads (FPKM) depicted the overall gene expression patterns. The study found that stage 2 as the period of highest gene expression activity during the thorns hardening process in B. glabra. Differential expression analysis revealed that during thorn-hardening, 1045 genes up-regulated and 391 genes down-regulated significantly in thorns at stage 2 compared to stage 1 (early stage of thorns formation). Meanwhile, 938 genes up-regulated and 784 genes down-regulated significantly in stems. At stage 3, as thorns became harder, 63 genes exhibited notable expression increase and 98 genes' expression decreased obviously within thorns, and 46 genes up-regulated and 29 genes down-regulated in stems, compared to stage 2. Phenylpropanoid biosynthesis was the key step in the hardening process of the thorns of B. glabra. The formation and hardening of thorns on the stem of B. glabra was a process in which lignin gradually accumulated in the thorns, and several genes were involved in this process. They include PAL (EC:4.3.1.24), CYP73A (EC:1.14.14.91), 4CL (EC:6.2.1.12), CCR (EC:1.2.1.44), CAD (EC:1.1.1.195) and POX (EC:1.11.1.7). Discussion: This transcriptome analysis offers insights into the molecular mechanisms underlying thorns development in this plant species.

5.
J Chromatogr A ; 1731: 465196, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39047444

RESUMEN

Magnetic multi-template molecularly imprinted polymers (M-mt-MIPs) were successfully synthesized by surface imprinting and multi-template imprinting strategy, using polydopamine coated magnetic multi-walled carbon nanotubes as supporting materials, five typical chlorophenols (CPs) as templates, methacrylic acid as functional monomer and ethylene glycol dimethacrylate as cross-linker. Compared to non-imprinted polymers (NIPs), the as-prepared M-mt-MIPs showed high adsorption capacity (32.58‒80.63 mg g-1), rapid mass transfer and specific selectivity for the five targeted CPs, which were applied as magnetic solid-phase extraction (MSPE) adsorbents. Parameters affecting MSPE efficiency were detailed investigated, such as adsorbents dosage, sample pH, extraction time, type and volume of desorption solvent and salt effect. Combined with HPLC-DAD, a simple, rapid and sensitive method was established, showing good linearity (2‒200 µg L-1), low limits of detection (0.32‒0.49 µg L-1), and high enrichment factors (35.2‒108). The developed M-mt-MIPs-MSPE-HPLC method was applied to enrich and determine CPs in tannery wastewater, wet-blue and crust leather, and satisfactory spiking recoveries were attained in the range of 73.95‒109.7% with relative standard deviations (RSDs) of 2.13-8.48%. This study provided a new alternative material and method to rapid simultaneously extract and analyze low concentration of typical CPs in complicated matrices.


Asunto(s)
Clorofenoles , Polímeros Impresos Molecularmente , Extracción en Fase Sólida , Cromatografía Líquida de Alta Presión/métodos , Clorofenoles/análisis , Clorofenoles/aislamiento & purificación , Polímeros Impresos Molecularmente/química , Extracción en Fase Sólida/métodos , Adsorción , Límite de Detección , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminantes Químicos del Agua/química , Impresión Molecular/métodos , Nanotubos de Carbono/química , Aguas Residuales/química , Polímeros/química , Indoles
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 322: 124859, 2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39047666

RESUMEN

Calcium ions (Ca2+) are key players in intracellular signaling as second messengers and play a pivotal role in various physiological processes. In this study, near-infrared water-soluble AgInS2 quantum dots (AIS QDs) for Ca2+ detection were synthesized by a one-step hydrothermal method. The fluorescence quantum yield (PL QY) of the quantum dots was as high as 23.99 %. With low cytotoxicity and good fluorescence properties, as well as short reaction time, the ternary AIS QDs have excellent synthesis efficiency and quantum yield, which are advantageous for Ca2+ detection and bioimaging applications. The fluorescence quenching of the quantum dots showed a clear linear relationship with calcium ion concentration in the range of 0-250 µM (detection limit: 0.65 µM). Confocal imaging experiments demonstrate the excellent biofluorescence imaging capability of AIS QDs. By tuning the Ag/In molar ratio, AIS QDs can achieve fluorescence emission in the near-infrared wavelength band (620-700 nm), and the near-infrared fluorescence imaging has deeper tissue penetration, less tissue absorption and photodamage, and lower interference of spontaneous fluorescence, which further expands the potential of QDs for bioimaging applications.

7.
Huan Jing Ke Xue ; 45(7): 4266-4278, 2024 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-39022972

RESUMEN

Antimony (Sb) is a major pollutant that poses a serious threat to the environment in the mining and processing of nonferrous metals, coexisting with sulfide and oxide of arsenic (As). Microorganisms play an important role in the migration, transformation, and repair of metals in soil. The ecological effects of bioavailable Sb and As on the microbial community in antimony mining areas(mining and smelting areas)are still poorly understood. The Wenzel method and high-throughput 16S rDNA amplicon were used to characterize soil pollution characteristics in different functional areas, and the relationship between the bacterial community and bioavailable concentrations have been investigated comprehensively. The results showed that: Chemical speciation of Sb and As were amorphous, and poorly crystalline hydrous oxides of Fe and Al (F3) > well-crystallized hydrous oxides of Fe and Al (F4) > residual phases (F5) > specifically adsorbed (F2) > non-specifically adsorbed (F1). According to the estimation of the potential ecological risk index (RI) and geo-accumulation index (Igeo), the Sb pollution degree was: smelting area > mining area > contrast area, in which the smelting area showed serious pollution, and the mining area showed moderate to severe pollution. The As pollution degree was: mining area > smelting area > contrast area, in which the mining area and smelting area showed moderate to severe pollution. High-throughput 16S rDNA amplicon showed that Proteobacteria was the most abundant phylum in mining and smelting areas; Kaistobacter, Pseudomonas, Sphingomonas, and Lysobacter were the most abundant microbial genera; Geobacter and Luteolibacter had a high LDA score in mining areas; and Thiobacillus had a high LDA score in antimony-contaminated areas. Spearman correlation analysis, variation partitioning analysis (VPA), and random forest (RF) analysis showed that Sb, As, bioavailable antimony [Sb (Bio)], and bioavailable arsenic [As (Bio)]were the main factors affecting the microbial community structure in different functional areas of antimony ore. Redundancy analysis (RDA) indicated that Sb and its bioavailable concentrations showed uniformly negative associations with the relative abundance of bacteria Nitrospirae and showed a significant positive correlation with Thiobacillus (P<0.05). The in-depth research on the ecological effects of bioavailable Sb and As on the bacterial community provides references and new perspectives for environmental monitoring and management.


Asunto(s)
Antimonio , Arsénico , Monitoreo del Ambiente , Minería , Microbiología del Suelo , Contaminantes del Suelo , China , Contaminantes del Suelo/análisis , Bacterias/clasificación , Bacterias/genética
8.
Artículo en Inglés | MEDLINE | ID: mdl-38994612

RESUMEN

INTRODUCTION: Chronic diabetic wounds pose a significant threat to the health of diabetic patients, representing severe and enduring complications. Globally, an estimated 2.5% to 15% of the annual health budget is associated with diabetes, with diabetic wounds accounting for a substantial share. Exploring new therapeutic agents and approaches to address delayed and impaired wound healing in diabetes becomes imperative. Traditional Chinese medicine (TCM) has a long history and remarkable efficacy in treating chronic wound healing. In this study, all topically applied proprietary Chinese medicines (pCMs) for wound healing officially approved by the National Medical Products Administration (NMPA) were collected from the NMPA TCM database. Data mining was employed to obtain a high-frequency TCM ingredients pair, Pearl-Borneol (1:1). METHOD: This study investigated the effect and molecular mechanism of the Pearl-Borneol pair on the healing of diabetic wounds by animal experiments and metabolomics. The results from animal experiments showed that the Pearl-Borneol pair significantly accelerated diabetic wound healing, exhibiting a more potent effect than the Pearl or Borneol treatment alone. Meanwhile, the metabolomics analysis identified significant differences in metabolic profiles in wounds between the model and normal groups, indicating that diabetic wounds had distinct metabolic characteristics from normal wounds. Moreover, Vaseline-treated wounds exhibited similar metabolic profiles to the wounds from the model group, suggesting that Vaseline might have a negligible impact on diabetic wound metabolism. In addition, wounds treated with Pearl, Borneol, and Pearl-Borneol pair displayed significantly different metabolic profiles from Vaseline-treated wounds, signifying the influence of these treatments on wound metabolism. Subsequent enrichment analysis of the metabolic pathway highlighted the involvement of the arginine metabolic pathway, closely associated with diabetic wounds, in the healing process under Pearl- Borneol pair treatment. Further analysis revealed elevated levels of arginine and citrulline, coupled with reduced nitric oxide (NO) in both the model and Vaseline-treated wounds compared to normal wounds, pointing to impaired arginine utilization in diabetic wounds. Interestingly, treatment with Pearl and Pearl-Borneol pair lowered arginine and citrulline levels while increasing NO content, suggesting that these treatments may promote the catabolism of arginine to generate NO, thereby facilitating faster wound closure. Additionally, borneol alone significantly elevated NO content in wounds, potentially due to its ability to directly reduce nitrates/nitrites to NO. Oxidative stress is a defining characteristic of impaired metabolism in diabetic wounds. RESULTS: The result showed that both Pearl and Pearl-Borneol pair decreased the oxidative stress biomarker methionine sulfoxide level in diabetic wounds compared to those treated with Vaseline, indicating that Pearl alone or combined with Borneol may enhance the oxidative stress microenvironment in diabetic wounds. CONCLUSION: In summary, the findings validate the effectiveness of the Pearl-Borneol pair in accelerating the healing of diabetic wounds, with effects on reducing oxidative stress, enhancing arginine metabolism, and increasing NO generation, providing a mechanistic basis for this therapeutic approach.

9.
Analyst ; 149(14): 3765-3772, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38842353

RESUMEN

Molecularly imprinted polymer (MIP)-based chromatographic separation materials, owing to their advantages of unique selectivity, low cost, suitable reproducibility, and acceptable stability, have attracted a great deal of research in different fields. In this investigation, a new type of MIP-coated silica (MIP/SiO2) separation material was developed using sulfamethoxazole as a template; the specific recognition ability of MIP and appropriate physicochemical properties (abundant Si-OH, suitable pore structure, good stability, etc.) of SiO2 microbeads were combined. The MIP/SiO2 separation materials were characterized carefully. Then, various compounds (such as sulfonamides, ginsenosides, nucleosides, and several pesticides) were used to comprehensively evaluate the chromatographic performances of the MIP/SiO2 column. Furthermore, the chromatographic performances of the MIP/SiO2 column were compared with those of other separation materials (such as non-imprinted polymer-coated silica, C18/SiO2, and bare silica) packed columns. The resolution value of all measured compounds was more than 1.51. The column efficiencies of 13 510 plates per meter (N m-1) for sulfamethoxazole, 11 600 N m-1 for ginsenoside Rd, and 10 510 N m-1 for 2'-deoxyadenosine were obtained. The acceptable results verified that the MIP/SiO2 column can be applied to separate highly polar drugs such as sulfonamides, ginsenosides, nucleosides, and pesticides.


Asunto(s)
Microesferas , Polímeros Impresos Molecularmente , Dióxido de Silicio , Dióxido de Silicio/química , Cromatografía Líquida de Alta Presión/métodos , Polímeros Impresos Molecularmente/química , Ginsenósidos/química , Ginsenósidos/análisis , Ginsenósidos/aislamiento & purificación , Impresión Molecular/métodos , Nucleósidos/química , Nucleósidos/aislamiento & purificación , Nucleósidos/análisis , Plaguicidas/análisis , Plaguicidas/química , Plaguicidas/aislamiento & purificación , Polímeros/química
10.
Opt Express ; 32(8): 13249-13265, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38859300

RESUMEN

Structured light 3D imaging systems commonly employ panel-based projectors or 1-axis MEMS mirrors with beam expander lens to project multi-frame barcodes or dot clouds, addressing challenges posed by objects with multi-scale feature sizes. However, these methods often result in large system volumes due to the required projection multi-lens modules, high hardware costs, or limited light pattern generation capabilities that hindering measurement precision enhancement. This paper introduces an innovative approach to reconfigurable spatial light pattern projection using a single bi-axial MEMS mirror with Lissajous scanning. In contrast to the pixel-by-pixel pre-defined image patterns encoding of conventional 2D laser beam scanning, the proposed method simply aligns the MEMS bi-axial resonance frequencies with laser pulse modulation, enabling the projection of diverse structured light patterns such as stripes, lines, dot matrices, and random dot clouds, which can adapt to different 3D imaging algorithms demands. It eliminates the need for multi-frame encoding and streamlines data caching, simplifies digital logic hardware. A prototype 3D imaging system was developed to demonstrate the mathematical model for laser modulation and the technical feasibility based on the proposed principle. Beyond its lens-free essence, the system supports focal-free optics and a compact projection form factor, which accommodates to a broad range of projection distances and field-of-views based on object's location. 3D depth map of polynomial surface and blocks objects are extracted through single-frame pattern projection with a relative high accuracy. The presented modulation theory for diverse structured light pattern generation opens avenues for versatile and compact 3D imaging applications of LiDAR and robotic 3D vision.

11.
Ecol Evol ; 14(6): e11626, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38919651

RESUMEN

Maternal monitoring of conspecifics is a crucial anti-predator strategy that also protects infants against risks within the social group. This study examines how maternal characteristics, infant characteristics, mother-infant distance, and the social environment affect maternal monitoring behaviors in free-ranging Tibetan macaques (Macaca thibetana). We observed 12 females with infants and analyzed their visual monitoring patterns. Our findings indicate that maternal rank significantly influences the time allocated to maternal visual monitoring, higher-ranking mothers spending less time than lower-ranking mothers. Maternal experience also played a role in monitoring strategies. Differences in monitoring strategies were observed based on maternal experience: first-time mothers (primiparity) engaged in longer but less frequent monitoring sessions compared to experienced mothers (multiparity). The time and frequency of maternal monitoring decreased as infants aged, and mothers with male infants showed higher levels of monitoring than those with female infants. The distance between mother and infant also affected visual monitoring behavior, with mothers increasing their monitoring levels when infants were nearby (1-5 m), rather than within reach (0-1 m) or beyond nearby (>5 m). Additionally, the presence of kin and non-kin influenced monitoring: as the number of nearby kin increased, monitoring levels decreased, while the presence of more non-kin males led to an increase in monitoring time, and higher-ranking non-kin neighbors increased the frequency of monitoring. These results suggest that Tibetan macaque mothers can adapt their visual monitoring to the social risks faced by their infants, adjusting their strategies to their status and the needs of their offspring.

12.
Anim Genet ; 55(4): 664-669, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38830632

RESUMEN

The primary purpose of genetic improvement in lean pig breeds is to enhance production performance. Owing to their similar breeding directions, Duroc and Pietrain pigs are ideal models for investigating the phenotypic convergence underlying artificial selection. However, most important economic traits are controlled by a polygenic basis, so traditional strategies for detecting selection signatures may not fully reveal the genetic basis of complex traits. The pathway-based gene network analysis method utilizes each pathway as a unit, overcoming the limitations of traditional strategies for detecting selection signatures by revealing the selection of complex biological processes. Here, we utilized 13 122 398 high-quality SNPs from whole-genome sequencing data of 48 Pietrain pigs, 156 Duroc pigs and 36 European wild boars to detect selective signatures. After calculating FST and iHS scores, we integrated the pathway information and utilized the r/bioconductor graphite and signet packages to construct gene networks, identify subnets and uncover candidate genes underlying selection. Using the traditional strategy, a total of 47 genomic regions exhibiting parallel selection were identified. The enriched genes, including INO80, FZR1, LEPR and FAF1, may be associated with reproduction, fat deposition and skeletal development. Using the pathway-based selection signatures detection method, we identified two significant biological pathways and eight potential candidate genes underlying parallel selection, such as VTN, FN1 and ITGAV. This study presents a novel strategy for investigating the genetic basis of complex traits and elucidating the phenotypic convergence underlying artificial selection, by integrating traditional selection signature methods with pathway-based gene network analysis.


Asunto(s)
Fenotipo , Polimorfismo de Nucleótido Simple , Selección Genética , Sus scrofa , Animales , Sus scrofa/genética , Masculino , Cruzamiento , Redes Reguladoras de Genes
13.
Environ Pollut ; 356: 124249, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38810677

RESUMEN

Disinfection by-products (DBPs) with heritage toxicity, mutagenicity and carcinogenicity are one kind of important new pollutants, and their detection and removal in water and wastewater has become a common challenge facing mankind. Advanced functional materials with ideal selectivity, adsorption capacity and regeneration capacity provide hope for the determination of DBPs with low concentration levels and inherent molecular structural similarity. Among them, molecularly imprinted polymers (MIPs) are favored, owing to their predictable structure, specific recognition and wide applicability. Also, metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs) with unique pore structure, large specific surface area and easy functionalization, attract increasing interest. Herein, we review recent advances in analytical methods based on the above-mentioned three functional materials for DBPs in water and wastewater. Firstly, MIPs, MOFs and COFs are briefly introduced. Secondly, MIPs, MOFs and COFs as extractants, recognition element and adsorbents, are comprehensively discussed. Combining the latest research progress of solid-phase extraction (SPE), sensor, adsorption and nanofiltration, typical examples on MIPs and MOFs/COFs based analytical and removal applications in water and wastewater are summarized. Finally, the application prospects and challenges of the three functional materials in DBPs analysis are proposed to promote the development of corresponding analytical methods.


Asunto(s)
Estructuras Metalorgánicas , Polímeros Impresos Molecularmente , Aguas Residuales , Contaminantes Químicos del Agua , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Polímeros Impresos Molecularmente/química , Estructuras Metalorgánicas/química , Adsorción , Desinfectantes/análisis , Desinfectantes/química , Desinfección/métodos , Porosidad , Extracción en Fase Sólida/métodos , Purificación del Agua/métodos , Impresión Molecular
14.
Environ Sci Technol ; 58(25): 11016-11026, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38743591

RESUMEN

Dissimilatory iron-reducing bacteria (DIRB) oxidize organic matter or hydrogen and reduce ferric iron to form Fe(II)-bearing minerals, such as magnetite and siderite. However, compared with magnetite, which was extensively studied, the mineralization process and mechanisms of siderite remain unclear. Here, with the combination of advanced electron microscopy and synchrotron-based scanning transmission X-ray microscopy (STXM) approaches, we studied in detail the morphological, structural, and chemical features of biogenic siderite via a growth experiment with Shewanella oneidensis MR-4. Results showed that along with the growth of cells, Fe(II) ions were increasingly released into solution and reacted with CO32- to form micrometer-sized siderite minerals with spindle, rod, peanut, dumbbell, and sphere shapes. They are composed of many single-crystal siderite plates that are fanned out from the center of the particles. Additionally, STXM revealed Fh and organic molecules inside siderite. This suggests that the siderite crystals might assemble around a Fh-organic molecule core and then continue to grow radially. This study illustrates the biomineralization and assembly of siderite by a successive multistep growth process induced by DIRB, also provides evidences that the distinctive shapes and the presence of organic molecules inside might be morphological and chemical features for biogenic siderite.


Asunto(s)
Hierro , Hierro/metabolismo , Shewanella/metabolismo , Minerales/metabolismo , Minerales/química , Oxidación-Reducción , Bacterias/metabolismo , Carbonatos , Compuestos Férricos
15.
Int J Med Robot ; 20(3): e2640, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38794828

RESUMEN

BACKGROUND: Accurately estimating the 6D pose of snake-like wrist-type surgical instruments is challenging due to their complex kinematics and flexible design. METHODS: We propose ERegPose, a comprehensive strategy for precise 6D pose estimation. The strategy consists of two components: ERegPoseNet, an original deep neural network model designed for explicit regression of the instrument's 6D pose, and an annotated in-house dataset of simulated surgical operations. To capture rotational features, we employ an Single Shot multibox Detector (SSD)-like detector to generate bounding boxes of the instrument tip. RESULTS: ERegPoseNet achieves an error of 1.056 mm in 3D translation, 0.073 rad in 3D rotation, and an average distance (ADD) metric of 3.974 mm, indicating an overall spatial transformation error. The necessity of the SSD-like detector and L1 loss is validated through experiments. CONCLUSIONS: ERegPose outperforms existing approaches, providing accurate 6D pose estimation for snake-like wrist-type surgical instruments. Its practical applications in various surgical tasks hold great promise.


Asunto(s)
Redes Neurales de la Computación , Instrumentos Quirúrgicos , Muñeca , Humanos , Muñeca/cirugía , Diseño de Equipo , Fenómenos Biomecánicos , Algoritmos , Procedimientos Quirúrgicos Robotizados/instrumentación , Procedimientos Quirúrgicos Robotizados/métodos , Imagenología Tridimensional/métodos , Rotación , Reproducibilidad de los Resultados , Cirugía Asistida por Computador/instrumentación , Cirugía Asistida por Computador/métodos , Análisis de Regresión
16.
Cyborg Bionic Syst ; 5: 0101, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38778878

RESUMEN

In the realm of precise medicine, the advancement of manufacturing technologies is vital for enhancing the capabilities of medical devices such as nano/microrobots, wearable/implantable biosensors, and organ-on-chip systems, which serve to accurately acquire and analyze patients' physiopathological information and to perform patient-specific therapy. Electrospinning holds great promise in engineering materials and components for advanced medical devices, due to the demonstrated ability to advance the development of nanomaterial science. Nevertheless, challenges such as limited composition variety, uncontrollable fiber orientation, difficulties in incorporating fragile molecules and cells, and low production effectiveness hindered its further application. To overcome these challenges, advanced electrospinning techniques have been explored to manufacture functional composites, orchestrated structures, living constructs, and scale-up fabrication. This review delves into the recent advances of electrospinning techniques and underscores their potential in revolutionizing the field of precise medicine, upon introducing the fundamental information of conventional electrospinning techniques, as well as discussing the current challenges and future perspectives.

17.
Curr Drug Metab ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38779735

RESUMEN

OBJECTIVE: Waiganfengsha Granule, an over-the-counter drug, is commonly used for treating windheat cold and sore throat in clinical settings. However, its material basis of medicinal efficacy is still unclear. In this study, an efficient integrated analytical strategy was established for its chemical and metabolite profiles study. METHODS: Firstly, to avoid the possible false-positive results of structural elucidation, an in-house component library that contains chemical constituents reported in the literature from the six individual medicines of Waiganfengsha Granule was established. Secondary, mass data post-processing techniques, including precursor ion list and neutral loss filtering, were applied to enhance the identification accuracy. Thirdly, for the rapid characterization of those absorbed components after oral administration in rats, the identified chemical constituents were used as candidate components for the serum analysis. By comparing the retention time and analyzing mass data, the metabolites in rat plasma were identified. RESULTS: As a result, 57 chemical ingredients were identified, including 21 phenolic acids, 9 alkaloids, 2 flavonoids, 5 lignins, 13 saponins, and 7 other compounds. Among these, 12 compounds were unambiguously identified by comparison with reference standards, and 45 were tentatively characterized by analyzing their accurate MS data, MS/MS fragmentation patterns, and also by comparison with those data reported in the literature. Additionally, 46 metabolites were detected and identified in rat plasma. CONCLUSION: This study is beneficial for understanding the chemical composition and metabolic profiles of Waiganfengsha Granule, and the results obtained might provide a solid basis for further studies on its functional mechanism.

18.
Animals (Basel) ; 14(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38791693

RESUMEN

Collective movement has emerged as a key area of interest in animal behavior. While individual differences are often viewed as a potential threat to group cohesion, growing evidence suggests that these differences can actually influence an animal's behavior as an initiator or follower during collective movements, thereby driving the group's movement and decision-making processes. To resolve the divergence, we asked how personality can affect the dynamics of collective movements in one group of free-ranging Tibetan macaques (Macaca thibetana) in Huangshan, China. We assessed individual personality using principal component analysis and applied the generalized linear mixed model and linear mixed model to examine the influence of personality on decision making during collective movements. Our findings reveled three distinct personality types among Tibetan macaques: sociability, boldness, and anxiousness. Individuals with higher sociability scores and rank, or those with lower anxiousness scores, were more likely to initiate successful collective movements. Older individuals were less successful in initiating movements compared to young adults. Leaders with lower anxiousness scores or higher rank attracted more followers, with females attracting larger groups than males. As for followers, individuals with higher rank tended to join the collective movement earlier. Additionally, individuals with higher sociability or boldness scores had shorter joining latency in collective movement. Finally, there was a longer joining latency for middle-aged adults compared to young adults. These results suggest that individual differences are a potential driver of collective movements. We provide some insights into the relationships between personality and decision making in Tibetan macaques.

19.
Small ; : e2403342, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38742947

RESUMEN

Perovskite solar cell (PSC) is a promising photovoltaic technology that achieves over 26% power conversion efficiency (PCE). However, the high materials costs, complicated fabrication process, as well as poor long-term stability, are stumbling blocks for the commercialization of the PSCs in normal structures. The hole transport layer (HTL)-free carbon-based PSCs (C-PSCs) are expected to overcome these challenges. However, C-PSCs have suffered from relatively low PCE due to severe energy loss at the perovskite/carbon interface. Herein, the study proposes to boost the hole extraction capability of carbon electrode by incorporating functional manganese (II III) oxide (Mn3O4). It is found that the work function (WF) of the carbon electrode can be finely tuned with different amounts of Mn3O4 addition, thus the interfacial charge transfer efficiency can be maximized. Besides, the mechanical properties of carbon electrode can also be strengthened. Finally, a PCE of 19.03% is achieved. Moreover, the device retains 90% of its initial PCE after 2000 h of storage. This study offers a feasible strategy for fabricating efficient paintable HTL-free C-PSCs.

20.
ACS Appl Mater Interfaces ; 16(22): 29338-29346, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38770998

RESUMEN

Tin dioxide (SnO2), in perovskite solar cells (PSCs), stands out as the material most suited to the electron transport layer (ETL), yielding advantages with regard to ease of preparation, high mobility, and favorable energy level alignment. Nonetheless, there is a chance that energy losses from defects in the SnO2 and interface will result in a reduction in the Voc. Consequently, optimizing the interfaces within solar cell devices is a key to augmenting both the efficiency and the stability of PSCs. Herein this present study, we introduced butylammonium chloride (BACl) into the SnO2 ETL. The resulting optimized SnO2 film mitigated interface defect density, thereby improving charge extraction. The robust bonding capability of negatively charged Cl- ions facilitated their binding with noncoordinated Sn4+ ions, effectively passivating defects associated with oxygen vacancies and enhancing charge transport within the SnO2 ETL. Concurrently, doped BA+ and Cl- diffused into the perovskite lattice, fostering perovskite grain growth and reducing the defects in perovskite. In comparison to the control device, the Voc saw a 70 mV increase, achieving a champion efficiency of 22.86%. Additionally, following 1000 h of ambient storage, the unencapsulated device based on SnO2 preburied with BACl retained around 90% of its initial photovoltaic conversion efficiency.

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