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1.
Mater Horiz ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958934

RESUMO

Developing high-efficiency electrocatalysts for nitrate-to-ammonia transformation holds significant promise for the production of ammonia, a crucial component in agricultural fertilizers and as a carbon-free energy carrier. In this study, we propose a viable strategy involving sulfur doping to modulate both the microstructure and electronic properties of CoSe2 for nitrate reduction. This approach remarkably enhances the conversion of nitrate to ammonia by effectively regulating the adsorption capability of nitrogenous intermediates. Specifically, sulfur-doped CoSe2 nanowires (S-CoSe2 NWs) exhibit a peak faradaic efficiency of 93.1% at -0.6 V vs. RHE and achieve the highest NH3 yield rate of 11.6 mg h-1 cm-2. Mechanistic investigations reveal that sulfur doping facilitates the creation of highly charged active sites, which enhance the adsorption of nitrite and subsequent hydrogenation, leading to improved selectivity towards ammonia production.

2.
Nanoscale ; 16(28): 13694-13702, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38967458

RESUMO

Asymmetric nickel oxyhydroxide (NiOOH) possesses multi-OH and O active sites on different surfaces, (001) and (001̄), which possibly causes a complicated catalytic process. Density functional theory (DFT) calculations reveal that the unconventional dual-site mechanism (UDSM) of the oxygen evolution reaction (OER) on NiOOH (001) and (001̄) exhibits significantly lower overpotentials of 0.80 and 0.77 V, compared to 1.24 and 1.62 V for the single-site mechanism (SSM), respectively. Through chemical doping or heterojunction modifications, the constructed NiOOH@FeOOH (001̄) heterojunction reduces the thermodynamic overpotential to 0.49 V from original 0.77 V undergoing the UDSM. Although Fe/Co-doping or physical compression yield similar or slightly higher overpotentials and are not conductive to facilitating the OER process by the UDSM, all dual-site paths exhibit obviously lower overpotentials than the SSM for pristine and regulated NiOOH (001) and (001̄) from the whole viewpoint. This work identifies a more reasonable and efficient dual-site OER mechanism, which is expected to help the rational design of highly-efficient electrocatalysts.

3.
ACS Nano ; 18(26): 17100-17110, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38902201

RESUMO

Two-dimensional (2D) van der Waals (vdWs) heterojunctions have been actively investigated in low-power-consumption and fast-response photodiodes owing to their atomically smooth interfaces and ultrafast interfacial charge transfer. However, achieving ultralow dark current and ultrafast photoresponse in the reported photovoltaic devices remains a challenge as the large built-in electric field in a heterojunction can not only speed up photocarrier transport but also increase the minority-carrier dark current. Here, we propose a high-spike barrier photodiode that can achieve both an ultralow dark current and an ultrafast response. The device is fabricated by the Te/WS2 heterojunction, while the band alignment can transition from type-II to type-I with a high electron barrier and a large hole built-in electronic field. The high electron barrier can greatly reduce the drift current of minority carriers and the generation current of the thermal carriers, while the large built-in electronic field can still speed up the photocarrier transport. The designed Te/WS2 vdWs photodiode yields an ultralow dark current of 8 × 10-14 A and an ultrafast photoresponse of 10/13 µs. Furthermore, a high-performance visible-light imager with a pixel resolution of 100 × 40 is demonstrated using the Te/WS2 vdWs photodiode. This work provides a comprehensive understanding of designing 2D-material-based photovoltaics with excellent overall performance.

4.
J Acoust Soc Am ; 155(5): 2934-2947, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38717201

RESUMO

Spatial separation and fundamental frequency (F0) separation are effective cues for improving the intelligibility of target speech in multi-talker scenarios. Previous studies predominantly focused on spatial configurations within the frontal hemifield, overlooking the ipsilateral side and the entire median plane, where localization confusion often occurs. This study investigated the impact of spatial and F0 separation on intelligibility under the above-mentioned underexplored spatial configurations. The speech reception thresholds were measured through three experiments for scenarios involving two to four talkers, either in the ipsilateral horizontal plane or in the entire median plane, utilizing monotonized speech with varying F0s as stimuli. The results revealed that spatial separation in symmetrical positions (front-back symmetry in the ipsilateral horizontal plane or front-back, up-down symmetry in the median plane) contributes positively to intelligibility. Both target direction and relative target-masker separation influence the masking release attributed to spatial separation. As the number of talkers exceeds two, the masking release from spatial separation diminishes. Nevertheless, F0 separation remains as a remarkably effective cue and could even facilitate spatial separation in improving intelligibility. Further analysis indicated that current intelligibility models encounter difficulties in accurately predicting intelligibility in scenarios explored in this study.


Assuntos
Sinais (Psicologia) , Mascaramento Perceptivo , Localização de Som , Inteligibilidade da Fala , Percepção da Fala , Humanos , Feminino , Masculino , Adulto Jovem , Adulto , Percepção da Fala/fisiologia , Estimulação Acústica , Limiar Auditivo , Acústica da Fala , Teste do Limiar de Recepção da Fala , Ruído
5.
Genesis ; 62(2): e23592, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38587195

RESUMO

Mesenchymal stem cells (MSCs) derived from fetal membranes (FMs) have the potential to exhibit immunosuppression, improve blood flow, and increase capillary density during transplantation. In the field of medicine, opening up new avenues for disease treatment. Chicken embryo chorioallantoic membrane (CAM), as an important component of avian species FM structure, has become a stable tissue engineering material in vivo angiogenesis, drug delivery, and toxicology studies. Although it has been confirmed that chorionic mesenchymal stem cells (Ch-MSCs) can be isolated from the outer chorionic layer of FM, little is known about the biological characteristics of MSCs derived from chorionic mesodermal matrix of chicken embryos. Therefore, we evaluated the characteristics of MSCs isolated from chorionic tissues of chicken embryos, including cell proliferation ability, stem cell surface antigen, genetic stability, and in vitro differentiation potential. Ch-MSCs exhibited a broad spindle shaped appearance and could stably maintain diploid karyotype proliferation to passage 15 in vitro. Spindle cells were positive for multifunctional markers of MSCs (CD29, CD44, CD73, CD90, CD105, CD166, OCT4, and NANOG), while hematopoietic cell surface marker CD34, panleukocyte marker CD45, and epithelial cell marker CK19 were negative. In addition, chicken Ch-MSC was induced to differentiate into four types of mesodermal cells in vitro, including osteoblasts, chondrocytes, adipocytes, and myoblasts. Therefore, the differentiation potential of chicken Ch-MSC in vitro may have great potential in tissue engineering. In conclusion, chicken Ch-MSCs may be an excellent model cell for stem cell regenerative medicine and chorionic tissue engineering.


Assuntos
Galinhas , Células-Tronco Mesenquimais , Animais , Embrião de Galinha , Membrana Corioalantoide , Diferenciação Celular/fisiologia , Células Cultivadas
6.
Water Res ; 256: 121577, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38593605

RESUMO

Nanoplastics (NPs) in wastewaters may present a potential threat to biological nitrogen removal in constructed wetlands (CWs). Iron ions are pivotal in microbially mediated nitrogen metabolism, however, explicit evidence demonstrating the impact of NPs on nitrogen removal regulated by iron utilization and metabolism remains unclear. Here, we investigated how NPs disturb intracellular iron homeostasis, consequently interfering with the coupling mechanism between iron utilization and nitrogen metabolism in CWs. Results indicated that microorganisms affected by NPs developed a siderophore-mediated iron acquisition mechanism to compensate for iron loss. This deficiency resulted from NPs internalization limited the activity of the electron transport system and key enzymes involved in nitrogen metabolism. Microbial network analysis further suggested that NPs exposure could potentially trigger destabilization in microbial networks and impair effective microbial communication, and ultimately inhibit nitrogen metabolism. These adverse effects, accompanied by the dominance of Fe3+ over certain electron acceptors engaged in nitrogen metabolism under NPs exposure, were potentially responsible for the observed significant deterioration in nitrogen removal (decreased by 30 %). This study sheds light on the potential impact of NPs on intracellular iron utilization and offers a substantial understanding of the iron-nitrogen coupling mechanisms in CWs.


Assuntos
Ferro , Nitrogênio , Áreas Alagadas , Ferro/metabolismo , Nitrogênio/metabolismo , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
7.
Molecules ; 28(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38067458

RESUMO

Currently, the process of an acidic oxygen evolution reaction (OER) necessitates the use of Iridium dioxygen (IrO2), which is both expensive and incredibly scarce on Earth. Ruthenium dioxygen (RuO2) offers high activity for acidic OERs and presents a potential substitution for IrO2. Nevertheless, its practical application is hindered by its relatively poor stability. In this study, we have developed Mn-doped RuO2 (Mn-RuO2) nanoarrays that are anchored on a titanium (Ti) mesh utilizing a two-step methodology involving the preparation of MnO2 nanoarrays followed by a subsequent Ru exchange and annealing process. By precisely optimizing the annealing temperature, we have managed to attain a remarkably low overpotential of 217 mV at 10 mA cm-2 in a 0.5 M H2SO4 solution. The enhanced catalytic activity of our Mn-RuO2 nanoarrays can be attributed to the electronic modification brought about by the high exposure of active sites, Mn dopant, efficient mass transfer, as well as the efficient transfer of electrons between the Ti mesh and the catalyst arrays. Furthermore, these self-supported Mn-RuO2 nanoarrays demonstrated excellent long-term stability throughout a chronoamperometry test lasting for 100 h, with no discernible changes observed in the Ru chemical states.

8.
J Obstet Gynaecol ; 43(2): 2282100, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38038254

RESUMO

BACKGROUND: In the current study, we sought to characterise the methylation haplotypes and nucleosome positioning patterns of placental DNA and plasma cell-free DNA of pregnant women with early-onset preeclampsia using whole genome bisulphite sequencing (WGBS) and methylation capture bisulphite sequencing (MCBS) and further develop and examine the diagnostic performance of a generalised linear model (GLM) by incorporating the epigenetic features for early-onset preeclampsia. METHODS: This case-control study recruited pregnant women aged at least 18 years who delivered their babies at our Hospital. In addition, non-pregnant women with no previous history of diseases were included. Placental samples of the villous parenchyma were taken at the time of delivery and venous blood was drawn from pregnant women during non-invasive prenatal testing at 12-15 weeks of pregnancy and nonpregnant women during the physical check-up. WGBS and MCBS were carried out of extracted genomic DNA. Then, we established the GLM by incorporating preeclampsia-specific methylation haplotypes and nucleosome positioning patterns and examined the diagnostic performance of the model by receiver operating characteristic (ROC) curve analysis. RESULTS: The study included 135 pregnant women and 50 non-pregnant women. Our high-depth MCBS revealed notably different DNA methylation and nucleosome positioning patterns between women with and without preeclampsia. Preeclampsia-specific hypermethylated sites were found predominantly in the promoter regions and particularly enriched in CTCF on the X chromosome. Totally, 2379 preeclampsia-specific methylation haplotypes were found across the entire genome. ROC analysis showed that the area under the ROC curve (AUC) was 0.938 (95%CI 0.877, 1.000). At a GLM cut-off of 0.341, the AUC was the maximum, with a sensitivity of 95.6% and a specificity of 89.7%. CONCLUSION: Pregnant women with early-onset preeclampsia exhibit DNA methylation and nucleosome positioning patterns in placental and plasma DNA.


Early-onset preeclampsia is a potentially dangerous condition that can have a profound impact on the health of both the expectant mother and her unborn child. This condition is particularly concerning because it's challenging to predict who may be affected using conventional methods such as monitoring blood pressure. In our research, we've developed an innovative, non-invasive approach to predict the onset of early preeclampsia. We do this by analysing the genetic material of the developing baby, which can be found in the mother's blood. Our method has shown remarkable accuracy in our testing populations, and its implications are substantial. By providing an early warning system, this breakthrough can benefit pregnant women immensely. It means that early-onset preeclampsia can be identified and addressed well before it becomes a serious health threat. This allows for timely medical interventions and treatments, significantly improving the well-being of both mothers and their precious little ones.


Assuntos
Ácidos Nucleicos Livres , Pré-Eclâmpsia , Gravidez , Feminino , Humanos , Adolescente , Adulto , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/genética , Placenta , Fator de Crescimento Placentário , Estudos de Casos e Controles , Nucleossomos , Biomarcadores , Fenótipo , Epigênese Genética , DNA
9.
Transl Cancer Res ; 12(11): 3016-3033, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38130306

RESUMO

Background: Ubiquitin-specific protease 7 (USP7) is a deubiquitinating enzyme that can affect or regulate a variety of cellular activities. The purpose of this study was to investigate therapeutic and immunologic effects of USP7 in hepatocellular carcinoma (HCC), and as well to evaluate potential mechanisms of action. Methods: USP7-related gene expression and clinical data were obtained from The Cancer Genome Atlas (TCGA) dataset, International Cancer Genome Consortium (ICGC) dataset, and Gene Expression Omnibus (GEO) dataset. Pathways associated with USP7 were determined by gene set enrichment analysis (GSEA). The relationships among USP7, immunity, and drug therapy were also investigated and potential mechanisms of action were explored. Results: TCGA database results demonstrated USP7 mRNA expression levels to be upregulated in HCC tissues. Results were validated with UALCAN, ICGC, and GSE10143 datasets, as well as immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) experiments and were consistent with TCGA database findings (all P<0.05). GSEA analysis demonstrated increased USP7 levels to be associated with CHEMOKINE, Janus kinase/signal transducer and activator of transcription (JAK-STAT), mitogen-activated protein kinase (MAPK), P53, vascular endothelial growth factor (VEGF), and wingless (WNT) signaling pathways. Based on immune correlation analysis, USP7 was dramatically associated with immune cells and immune checkpoint molecules. In terms of drug therapy, USP7 expression levels were significantly related to HCC sensitivity to ciclosporin, talazoparib, dabrafenib, trametinib, paclitaxel, sorafenib, bortezomib, sunitinib, and crizotinib. Based on these results, we mechanistically propose an association between USP7 and these four drug targets: B-Raf proto-oncogene serine/threonine protein kinase (BRAF), mitogen-activated extracellular signal-regulated kinase (MEK), DNA topoisomerase I (TOPOI), and poly ADP-ribose polymerase (PARP). Conclusions: USP7 plays a therapeutic and immunological role in HCC. The four drug targets BRAF, MEK, TOPOI, and PARP are implicated in the USP7 mechanism of action.

10.
Heliyon ; 9(11): e21970, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034725

RESUMO

Exploring the influence of farmland transfer on poverty among the mid-aged and elderly rural households is of great value in preventing them from returning to poverty and in solving the problem of rural poverty. Based on the propensity score matching with differences in differences approach, this paper measures and compares the effects of farmland transfer-in and transfer-out on the vulnerability to poverty of the mid-aged and elderly rural households by using the tracking survey of China Health and Retirement Longitudinal Study (CHARLS) in 2015 and 2018. The findings reveal that: (1) The anti-poverty effect of farmland transfer is "asymmetric". Farmland transfer-in can significantly reduce the vulnerability to poverty of the lessee households, but farmland transfer-out has no such effect. (2) Obvious regional and household differences exist in the anti-poverty effect of farmland transfer. The anti-poverty effects of farmland transfer-in in the eastern and central regions are higher than in other regions. The greater vulnerability to poverty is associated with the more obvious anti-poverty effect of farmland transfer-in. These results benefit the government to strengthen the reforms related to farmland transfer and anti-poverty.

11.
Front Oncol ; 13: 1256012, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023156

RESUMO

Purpose: Liver abscess is a rare and serious complication after transarterial chemoembolization (TACE) for liver cancer; however, its impact on the prognosis is unclear. This retrospective study examined the outcomes of patients with liver abscess formation following TACE for malignant liver tumors to elucidate the impact of liver abscess formation on the prognosis of these patients. Methods: From January 2017 to January 2022, 1,387 patients with malignant tumors underwent 3,341 sessions of TACE at our hospital. Clinical characteristics of patients at baseline and follow-up were examined, including treatment and outcome of liver abscess, tumor response to the TACE leading to liver abscess, and overall survival time. Results: Of 1,387 patients, 15 (1.1%) patients with liver abscess complications after TACE resulted in a total of 16 (0.5%) cases of liver abscess after 3,341 TACE sessions (including one patient with two events). After antibiotic or percutaneous catheter drainage (PCD) treatment, all the infections associated with liver abscesses were controlled. In the PCD group, eight patients died before drainage tube removal, one retained the drainage tube until the end of follow-up, and five underwent drainage tube removal; the mean drainage tube removal time was 149.17 ± 134.19 days. The efficacy of TACE leading to liver abscess was evaluated as partial response (18.75%), stable disease (37.5%), and progressive disease (43.75%). Eleven patients died during the follow-up period owing to causes unrelated to infections caused by liver abscesses. The survival rates at 3 months, 6 months, 1 year, and 5 years were 86.7%, 50.9%, 25.5%, and 17%, respectively. Conclusion: Patients with liver abscess formation following TACE for malignant liver tumors experienced prolonged drainage tube removal time after PCD; while this condition did not directly cause death, it indirectly contributed to a poor prognosis in these patients.

12.
Chemosphere ; 345: 140497, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866500

RESUMO

In this study, 26 typical antibiotics in the suspended matter of the Fen River basin were analyzed during the wet and dry seasons, and the main sources of antibiotic contamination were further identified. The results showed that the concentrations of antibiotics in the suspended matter varied seasonally. Sixteen antibiotics were detected in the suspended matter during the wet season with an average concentration of 463.56 ng/L. However, a total of 21 antibiotics were detected in the dry season, with an average concentration of 106.00 ng/L. The concentration of chloramphenicol antibiotics was outstanding in the wet season and dry season. The spatial distribution of the antibiotics in suspended matter showed little spatial discrepancy during the wet season. During the dry season, nevertheless, the concentration was higher upstream than midstream and downstream. The main sources of antibiotics in the Fen River Basin were livestock and poultry breeding, wastewater from wastewater treatment plants (WWTPs), agricultural drainage, domestic sewage, and pharmaceutical wastewater. Wastewater from WWTPs and domestic sewage were identified as two primary sources in the suspended matter during the wet season, with wastewater from WWTPs contributing the most accounting for 37%. While the most significant source of antibiotics in the suspended matter in the dry season was pharmaceutical wastewater, accounting for 36%. In addition, the contribution proportion of sources for antibiotics exhibited discrepant spatial distribution characteristics. In the wet season, wastewater from WWTPs dominated in the upstream and midstream, and livestock and poultry breeding was prominent in the midstream and downstream. Pharmaceutical wastewater was the main source in the midstream and downstream regions during the dry season.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Esgotos/análise , Antibacterianos/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Estações do Ano , Preparações Farmacêuticas , China
13.
Nanomaterials (Basel) ; 13(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37836262

RESUMO

Water electrolysis is a compelling method for the production of environmentally friendly hydrogen, minimizing carbon emissions. The electrolysis of water heavily relies on an effective and steady oxygen evolution reaction (OER) taking place at the anode. Herein, we introduce a highly promising catalyst for OER called CoSe2@NiFeOOH arrays, which are supported on nickel foam. This catalyst, referred to as CoSe2@NiFeOOH/NF, is fabricated through a two-step process involving the selenidation of a Co-based porous metal organic framework and subsequent electrochemical deposition on nickel foam. The CoSe2@NiFeOOH/NF catalyst demonstrates outstanding activity for the OER in an alkaline electrolyte. It exhibits a low overpotential (η) of 254 mV at 100 mA cm-2, a small Tafel slope of 73 mV dec-1, and excellent high stability. The good performance of CoSe2@NiFeOOH/NF can be attributed to the combination of the high conductivity of the inner layer and the synergistic effect between CoSe2 and NiFeOOH. This study offers an effective method for the fabrication of highly efficient catalysts for an OER.

14.
Proc Natl Acad Sci U S A ; 120(40): e2302361120, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37738291

RESUMO

The almost simultaneous emergence of major animal phyla during the early Cambrian shaped modern animal biodiversity. Reconstructing evolutionary relationships among such closely spaced branches in the animal tree of life has proven to be a major challenge, hindering understanding of early animal evolution and the fossil record. This is particularly true in the species-rich and highly varied Mollusca where dramatic inconsistency among paleontological, morphological, and molecular evidence has led to a long-standing debate about the group's phylogeny and the nature of dozens of enigmatic fossil taxa. A critical step needed to overcome this issue is to supplement available genomic data, which is plentiful for well-studied lineages, with genomes from rare but key lineages, such as Scaphopoda. Here, by presenting chromosome-level genomes from both extant scaphopod orders and leveraging complete genomes spanning Mollusca, we provide strong support for Scaphopoda as the sister taxon of Bivalvia, revitalizing the morphology-based Diasoma hypothesis originally proposed 50 years ago. Our molecular clock analysis confidently dates the split between Bivalvia and Scaphopoda at ~520 Ma, prompting a reinterpretation of controversial laterally compressed Early Cambrian fossils, including Anabarella, Watsonella, and Mellopegma, as stem diasomes. Moreover, we show that incongruence in the phylogenetic placement of Scaphopoda in previous phylogenomic studies was due to ancient incomplete lineage sorting (ILS) that occurred during the rapid radiation of Conchifera. Our findings highlight the need to consider ILS as a potential source of error in deep phylogeny reconstruction, especially in the context of the unique nature of the Cambrian Explosion.


Assuntos
Bivalves , Animais , Filogenia , Biodiversidade , Movimento Celular , Suplementos Nutricionais
15.
Orphanet J Rare Dis ; 18(1): 305, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37759207

RESUMO

OBJECTIVE: To share our experience on prenatal diagnosis of 7q11.23 microduplication syndrome and to further delineate the fetal phenotypes of the syndrome. METHODS: A retrospective study was conducted to evaluate seven cases of dup7q11.23 syndrome diagnosed prenatally by chromosomal microarray (CMA). Clinical data were reviewed, including maternal characteristics, indications for prenatal diagnosis, sonographic findings, CMA results, pregnancy outcomes and follow-ups. RESULTS: Seven cases, including 2 pairs of MCDA twins, were prenatally identified with dup7q11.23 syndrome. The most common prenatal sonographic features were ventriculomegaly, low-lying conus medullaris, and dilated ascending aorta. All 7 fetuses presented with typical 7q11.23 duplications (1.40-1.55 Mb). Parental chromosome analysis was performed in four pairs of parents, and indicated that the duplications of Case 6 and 7 were inherited from their asymptomatic mother. CONCLUSION: Our case series suggest that prenatal features of dup7q11.23 cases are diversified, with ventriculomegaly and low-lying conus medullaris being the most common intrauterine phenotypes. Additionally, cleft palate, dilated ascending aorta, and renal abnormalities were also observed, and should be taken into consideration in subsequent studies.


Assuntos
Hidrocefalia , Diagnóstico Pré-Natal , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Feto , Fenótipo , Síndrome
16.
Nanomaterials (Basel) ; 13(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37630881

RESUMO

Lewis acid zeolites play an important role in industrially important green reactions closely related to fine chemical and biomass conversion. Titanium-doped TS-1 zeolite is a milestone Lewis acid zeolite widely used in industrially significant green oxidation processes with hydrogen peroxide as an oxidant under mild conditions. TS-1 zeolites are normally synthesized in basic conditions under hydrothermal treatment. Up to now, there has still been no success in synthesizing active TS-1 Lewis acid zeolites by using inorganic alkali, e.g., NaOH or KOH as base, which is cheaper and more stable compared to the quaternary ammonium hydroxide or organic amines used in traditional synthesis. Here, an inorganic base of NaOH was employed in synthesizing active TS-1 zeolites for the first time. The crucial factor was the control of adverse effects of sodium cations on the incorporation of active titanium cations. Higher catalytic activity was achieved by further reducing the size of the TS-1 crystal by using the seed-added strategy, which uses the catalytic activity of a commercial catalyst, the production cost being much lower than commercial TS-1 catalysts, indicating great commercial potential and the possibility of preparing other cheap Lewis acid catalysts by using inorganic alkali.

17.
Prenat Diagn ; 43(10): 1355-1365, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37526276

RESUMO

OBJECTIVE: To explore the intrauterine phenotypic spectrum of short stature homeobox-containing (SHOX) gene-associated skeletal dysplasia and provide genetic counseling at-risk pregnancies. METHOD: We analyzed the fetuses with SHOX-microdeletions identified by single nucleotide polymorphism (SNP)-array. The intrauterine phenotypes and outcomes were further elaborated. RESULTS: Nine fetuses carrying a single SHOX-microdeletion were reported, with deletion sizes ranging from 0.134 to 1.35 Mb. Shortened long bones were observed in all fetuses, varying from -2.0 standard deviation (SD) to -5.3 SD. Moreover, all cases had a femur length/foot ratio less than 0.87 and a femur/abdominal circumference ratio greater than 0.16, suggesting that non-lethal skeletal dysplasia may be involved. Two fetuses showed intrauterine growth restriction, and two had nasal bone hypoplasia. Prenatal ultrasonography did not reveal other obvious anomalies, including the Madelung deformity. Five microdeletions were inherited and one was de novo. Five terminations and four newborns were recorded. Two newborns had normal stature, and two were short-statured (height <3rd percentile), with one having inflexible wrists. CONCLUSIONS: SHOX haploinsufficiency may manifest with shortened fetal long bones. The combination of history taking, prenatal ultrasonography, and SNP-array can prompt early prenatal diagnosis and timely postnatal treatment of SHOX-associated skeletal dysplasia.


Assuntos
Feto , Transtornos do Crescimento , Gravidez , Feminino , Humanos , Recém-Nascido , Proteína de Homoeobox de Baixa Estatura/genética , Transtornos do Crescimento/genética , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/genética , Fenótipo , Proteínas de Homeodomínio/genética
18.
Nat Commun ; 14(1): 4822, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563114

RESUMO

The corrosive anions (e.g., Cl-) have been recognized as the origins to cause severe corrosion of anode during seawater electrolysis, while in experiments it is found that natural seawater (~0.41 M Cl-) is usually more corrosive than simulated seawater (~0.5 M Cl-). Here we elucidate that besides Cl-, Br- in seawater is even more harmful to Ni-based anodes because of the inferior corrosion resistance and faster corrosion kinetics in bromide than in chloride. Experimental and simulated results reveal that Cl- corrodes locally to form narrow-deep pits while Br- etches extensively to generate shallow-wide pits, which can be attributed to the fast diffusion kinetics of Cl- and the lower reaction energy of Br- in the passivation layer. Additionally, for the Ni-based electrodes with catalysts (e.g., NiFe-LDH) loading on the surface, Br- causes extensive spalling of the catalyst layer, resulting in rapid performance degradation. This work clearly points out that, in addition to anti-Cl- corrosion, designing anti-Br- corrosion anodes is even more crucial for future application of seawater electrolysis.

19.
Nanomaterials (Basel) ; 13(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37446438

RESUMO

Titanium silicalite-1 (TS-1) is a milestone heterogeneous catalyst with single-atom tetrahedral titanium incorporated into silica framework for green oxidation reactions. Although TS-1 catalysts have been industrialized, the strategy of direct hydrothermal synthesis usually produces catalysts with low catalytic activities, which has still puzzled academic and industrial scientists. Post-treatment processes were widely chosen and were proven to be an essential process for the stable production of the high-activity zeolites with hollow structures. However, the reasons why post-treatment processes could improve catalytic activity are still not clear enough. Here, high-performance hollow TS-1 zeolites with nano-sized crystals and nano-sized cavities were synthesized via post-treatment of direct-synthesis nano-sized TS-1 zeolites. The influencing factors of the fabricating processes on their catalytic activities were investigated in detail, including the content of alkali metal ions, the state of titanium centers, hydrophilic/hydrophobic properties, and accessibility of micropores. The post-treatment processes could effectively solve these adverse effects to improve catalytic activity and to stabilize production. These findings contribute to the stable preparation of high-performance TS-1 catalysts in both factories and laboratories.

20.
Environ Sci Pollut Res Int ; 30(26): 69683-69696, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37140859

RESUMO

Non-point source (NPS) pollution has always been the focus of research worldwide, and understanding the migration process is the basis for effective control of NPS pollution. In this study, the SWAT model and digital filtering algorithm were combined to explore the contribution of NPS pollution that migrated with underground runoff (UR) process to the Xiangxi River watershed. The results showed that the surface runoff (SR) was the main migration process of NPS pollution, while the contribution of NPS pollution that migrated with the UR process only accounted for 30.9%. With the decrease in annual precipitation among the three selected hydrological years, the proportion of NPS pollution that migrated with the UR process for TN decreased, whereas the proportion for TP increased. The contribution of NPS pollution migrated with UR process varied remarkably during different months. Although the maximum total load and the load of NPS pollution that migrated with the UR process for TN and TP all appeared in the wet season, due to the hysteresis effect, the load of NPS pollution that migrated with the UR process for TP appeared 1 month later than the total load of NPS pollution. With an increase in precipitation from the dry season to the wet season, the proportion of NPS pollution that migrated with the UR process for TN and TP decreased gradually, and the degree of decrease in NPS pollution that migrated with the UR process for TP was more evident than that for TN. Besides, being affected by topography, land use, and other factors, the proportion of NPS pollution that migrated with the UR process for TN decreased from 80% in upstream areas to 9% in downstream areas, while that for TP reached a maximum of 20% in downstream areas. Based on the research results, the contribution of soil and groundwater cumulative nitrogen and phosphorus should be considered, and different managements and control measures for different migration routes should be adopted in controlling pollution.


Assuntos
Poluição Difusa , Poluentes Químicos da Água , Poluição Difusa/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Poluição Ambiental , Nitrogênio/análise , Fósforo/análise , Algoritmos , China
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