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1.
Microb Pathog ; 191: 106649, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38636568

RESUMEN

Bombyx mori nucleopolyhedrovirus (BmNPV) is a very common and infectious virus that affects silkworms and hinders silk production. To investigate the intestinal flora of BmNPV-resistant and BmNPV-sensitive silkworm varieties, 16 S rDNA high-throughput sequencing was performed. The results of the cluster analysis showed that the intestinal flora of the resistant silkworm variety was more abundant than that of the sensitive silkworm variety. This was found even when infection with BmNPV caused a sharp decline in the number of intestinal floral species in both resistant and sensitive silkworm varieties. The abundances of the intestinal flora, including Aureimonas, Ileibacterium, Peptostreptococcus, Pseudomonas, Enterococcus, and Halomonas, in the resistant variety were considerably greater after infection with BmNPV than those in the sensitive variety. After infection with BmNPV, four kinds of important intestinal bacteria, namely, f_Saccharimonadaceae, Peptostreptococcus, Aureirmonas, and f_Rhizobiaceae, were found in the resistant silkworm variety. In the sensitive silkworm variety, only Faecalibaculum was an important intestinal bacterium. The differential or important bacteria mentioned above might be involved in immunoreaction or antiviral activities, especially in the intestines of BmNPV-resistant silkworms. By conducting a functional enrichment analysis, we found that BmNPV infection did not change the abundance of important functional components of the intestinal flora in resistant or sensitive silkworm varieties. However, some functional factors, such as the biosynthesis, transport, and catabolism of secondary metabolites (e.g., terpenoids and polyketides) and lipid transport and metabolism, were more important in the resistant silkworm variety than in the sensitive variety; thus, these factors may increase the resistance of the host to BmNPV. To summarize, we found significant differences in the composition, abundance, and function of the intestinal flora between resistant and sensitive silkworm varieties, especially after infection with BmNPV, which might be closely related to the resistance of resistant silkworm varieties to BmNPV.

2.
BMC Psychiatry ; 24(1): 210, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500067

RESUMEN

BACKGROUND: Current research has been focusing on non-suicidal self-injury (NSSI) behaviors among adolescents with depression. Although family intimacy and adaptability are considered protective factors for NSSI, evidence supporting this relationship is lacking. OBJECTIVE: This study aims to examine the mechanisms operating in the relationship between family intimacy and adaptability and NSSI behaviors among adolescents. METHODS: A self-administered general demographic information questionnaire, the Behavioral Functional Assessment Scale for Non-Suicidal Self-Injury, the Family Intimacy and Adaptability Scale, the Connor-Davidson Resilience Scale, and the Self-Assessment of Depression Scale were distributed among adolescents with depression in three tertiary hospitals in Jiangsu Province. RESULTS: The relationship between family intimacy and adaptability and NSSI was assessed among 596 adolescents with depression. The results revealed the following: (1) Family intimacy and adaptability were negatively correlated with NSSI behavior. (2) Psychological resilience and depression levels acted as chain mediators in the relationship between family intimacy and adaptability and NSSI behavior. CONCLUSIONS: Enhancing psychological resilience, controlling depressive symptoms, and reducing depression severity among adolescents by improving their family intimacy and adaptability are conducive to preventing and mitigating their NSSI behaviors.


Asunto(s)
Resiliencia Psicológica , Conducta Autodestructiva , Adolescente , Humanos , Análisis de Mediación , Conducta Autodestructiva/psicología , Pruebas Psicológicas
3.
Parasitol Res ; 123(1): 59, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38112902

RESUMEN

Nosema bombycis, an obligate intracellular parasite, is a single-celled eukaryote known to infect various tissues of silkworms, leading to the manifestation of pebrine. Trehalase, a glycosidase responsible for catalyzing the hydrolysis of trehalose into two glucose molecules, assumes a crucial role in thermal stress tolerance, dehydration, desiccation stress, and asexual development. Despite its recognized importance in these processes, the specific role of trehalase in N. bombycis remains uncertain. This investigation focused on exploring the functions of trehalase 3 in N. bombycis (NbTre3). Immunofluorescence analysis of mature (dormant) spores indicated that NbTre3 primarily localizes to the spore membrane or spore wall, suggesting a potential involvement in spore germination. Reverse transcription-quantitative polymerase chain reaction results indicated that the transcriptional level of NbTre3 peaked at 6 h post N. bombycis infection, potentially contributing to energy storage for proliferation. Throughout the life cycle of N. bombycis within the host cell, NbTre3 was detected in sporoplasm during the proliferative stage rather than the sporulation stage. RNA interference experiments revealed a substantial decrease in the relative transcriptional level of NbTre3, accompanied by a certain reduction in the relative transcriptional level of Nb16S rRNA. These outcomes suggest that NbTre3 may play a role in the proliferation of N. bombycis. The application of the His pull-down technique identified 28 proteins interacting with NbTre3, predominantly originating from the host silkworm. This finding implies that NbTre3 may participate in the metabolism of the host cell, potentially utilizing the host cell's energy resources.


Asunto(s)
Bombyx , Microsporidiosis , Nosema , Animales , Trehalasa/genética , Trehalasa/metabolismo , Esporas Fúngicas/metabolismo , Nosema/genética , Bombyx/parasitología
4.
Eur J Protistol ; 91: 126025, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37890439

RESUMEN

Trachelocercids are common ciliates in marine sandy intertidal zones, however, only few species have been described using modern taxonomic techniques, with several earlier descriptions still lacking primary data, such as a detailed description of the oral ciliature. For this reason, systematics of the family Trachelocercidae Kent, 1881 resulted in paraphyletic genera and needs a critical revision. As an attempt to fill the gap of knowledge for this group, this study presents one new species description, Tracheloraphis apodiscolor n. sp., along with redescriptions of three lesser-known trachelocercid species, Trachelocerca bodiani (Dragesco, 1963) Dragesco, 2002, Trachelocerca ditis (Wright, 1982) Foissner & Dragesco, 1996 and Prototrachelocerca fasciolata (Sauerbrey, 1928) Foissner, 1996, collected from coastal marine habitats at Qingdao (China), using live and protargol-stained specimens. Tracheloraphis apodiscolor n. sp. can be distinguished from its closest related congener, T. discolor, by a shorter body length and fewer somatic kineties. Molecular data of T. apodiscolor n. sp. and T. bodiani were provided for the first time. Additionally, based on the Qingdao populations, we provide improved diagnoses for T. ditis and P. fasciolata. Phylogenetic analyses were performed and discussed, as there is strong support for paraphyly of the genera Tracheloraphis and Trachelocerca. In general, more integrative studies based on taxonomy, ultrastructure as well as molecular data are needed to properly shed light on the systematics of trachelocercids.


Asunto(s)
Cilióforos , Filogenia , Cilióforos/genética , China , Ecosistema
5.
Am J Cancer Res ; 13(4): 1310-1328, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37168340

RESUMEN

Guanylate binding protein 5 (GBP5) is a member of the interferon (IFN)-inducible large guanosine triphosphate hydrolases (GTPase) family that regulates cell-autonomous immunity and malignant tumor transformation. However, its specific roles and underlying mechanisms GBP5 in gastric cancer (GC) remain unknown. In this study, we aimed to determine the role GBP5 and underlying mechanism of GBP5 in GC cell progression. Potential oncogenic roles of GBP5 in GC as well as its relationship with the tumor immune microenvironment (TIME) were comprehensively evaluated using bioinformatics analysis. Protein expression levels of GBP5 and their correlation with clinicopathological features of patients were assessed using immunohistochemistry. In addition, diverse in vitro functional experiments were performed to identify the functions of GBP5 in GC. Downstream targets of GBP5 were identified using RNA-sequencing analysis and verified using western blotting or quantitative polymerase chain reaction analysis in different cell lines. GBP5 expression is commonly upregulated and promotes the proliferation and migration of GC cells. Mechanistically, GBP5 was regulated by the IFNγ-Janus kinase (JAK1)-signal transducer and activator of transcription 1 (STAT1) axis and induced CXCL8 expression. Interestingly, GBP5-induced CXCL8 regulated the JAK1-STAT1 signaling pathway to form a positive feedback loop. Moreover, GBP5 is closely related to the TIME and may be used as a biomarker for predicting the efficacy of immunotherapy. Our findings revealed a new JAK1-STAT1/GBP5/CXCL8 pathway and highlighted the value of GBP5 as a predictive biomarker and novel target for GC intervention.

6.
Zool Res ; 43(5): 827-842, 2022 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-35993134

RESUMEN

During faunal studies of psammophilic ciliates along the coast of Qingdao, China, several marine karyorelictean species were isolated. Among them, four species within the genus Remanella were investigated, including two species new to science: i.e., R. rugosa, Remanella elongata sp. nov., Remanella aposinica sp. nov., and R. unicorpusculata. Remanella rugosa has been reported several times, but this study is the first to provide detailed morphological characters and phylogenetics. Remanella elongata sp. nov. can be distinguished from its congeners by the presence of complex cortical granules, fewer macronuclei, and longer body size. Remanella aposinica sp. nov. differs from its congeners by having 14-17 right lateral ciliary rows and 24-37 dikinetids of intrabuccal kinety. Poorly known Remanella rugosa var. unicorpusculata (Kahl, 1933) Foissner, 1996 should be elevated from subspecies to species level, Remanella unicorpusculata (Foissner, 1996) stat. nov., based on detailed redescriptions with statistical data, living morphology, infraciliature, and species definitions. Small subunit (SSU) rDNA was sequenced for the four species, and phylogenetic analysis revealed that all known taxa in Remanella formed the outline branch to the genus Loxodes with moderate to high bootstrap support among Remanella lineages.


Asunto(s)
Cilióforos , Animales , China , Cilióforos/clasificación , Cilióforos/genética , ADN Ribosómico/genética , Filogenia
7.
Folia Microbiol (Praha) ; 67(6): 891-898, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35750981

RESUMEN

Silkworm diseases caused by fungi infection occur frequently in sericulture and brought huge economic loss to sericulture. However, on the other hand, some fungi such as Beauveria bassiana, as an important entomological fungus, play an important role in biological control of insect pests. Here, two fungal pathogens causing yellow muscardine were isolated from the silkworm and named as SZY1 and SZY2. These two strains showed almost the same conidial morphology which were smooth, near-spherical, spherical, or ovoid and 2.7 ± 0.6 µm × 2.5 ± 0.9 µm in size, and the hyphal growth rate was also similar. However, the conidia production of SZY2 was almost twice as many as that of SZY1. The complete ribosomal RNA gene was sequenced and analyzed. As a result, the gene sequences of internal transcript space 1 (ITS1)-5.8S rRNA-internal transcript space 2 (ITS2) of SZY1 and SZY2 were identical in sequence and size, and for 18S rRNA, 28S rRNA, and intergenic spacer (IGS), the gene identity of SZY1 to SZY2 was 99%, 99%, and 98%, respectively. Results of phylogenetic analysis based on either ITS1-5.8S rRNA-ITS2 or 18S rRNA showed that both SZY1 and SZY2 were closely related to Beauveria bassiana. These results revealed that the pathogens of yellow muscardine SZY1 and SZY2 were identified as two different strains of Beauveria bassiana, which could provide diagnostic evidence for silkworm muscardine and was helpful for the research and development of novel Bombyx batryticatus and fungal biological insecticide.


Asunto(s)
Beauveria , Bombyx , Animales , Bombyx/genética , Bombyx/microbiología , Beauveria/genética , ARN Ribosómico 18S , Filogenia , ARN Ribosómico 5.8S
8.
Mol Phylogenet Evol ; 169: 107406, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35031457

RESUMEN

The class Karyorelictea, a unique assemblage of ciliates, is a key group in deciphering ciliate evolution history. However, the systematic relationships among members of this class remain poorly understood. Here we newly obtained eight small subunit (SSU) rDNA, 24 large subunit (LSU) rDNA, and 25 ITS1-5.8S-ITS2 sequences (covering 25 species, 10 genera and 4 out of 6 families) to analyze the phylogenetic relationships within Karyorelictea. Our results indicate that: (1) considering its unique morphology and early branching position in the SSU rDNA-based tree, the family Wilbertomorphidae represents a new taxon at order level, hence the new order Wilbertomorphida n. ord. is established; (2) all five families with available molecular information are monophyletic, as expected, and the orders Loxodida and Protostomatida show a closer relationship than with Protoheterotrichida; (3) in Trachelocercidae, the compound circumoral kineties is believed to be a plesiomorphic feature while the single circumoral kinety is synapomorphic; and (4) the freshwater genus Loxodes could be derived from the marine Remanella and both share most morphological features. Taken together, these muti-gene analyses provide further insights into the phylogeny of the diverse clades in Karyorelictea.


Asunto(s)
Cilióforos , Cilióforos/genética , ADN Protozoario/genética , ADN Ribosómico/genética , Humanos , Filogenia , Análisis de Secuencia de ADN
9.
Front Microbiol ; 12: 768724, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34925276

RESUMEN

Four suctorian ciliates, Cyclophrya magna Gönnert, 1935, Peridiscophrya florea (Kormos & Kormos, 1958) Dovgal, 2002, Heliophrya rotunda (Hentschel, 1916) Matthes, 1954 and Dendrosoma radians Ehrenberg, 1838, were collected from a freshwater lake in Ningbo, China. The morphological redescription and molecular phylogenetic analyses of these ciliates were investigated. Phylogenetic analyses inferred from SSU rDNA sequences show that all three suctorian orders, Endogenida, Evaginogenida, and Exogenida, are monophyletic and that the latter two clusters as sister clades. The newly sequenced P. florea forms sister branches with C. magna, while sequences of D. radians group with those from H. rotunda within Endogenida. The family Heliophryidae, which is comprised of only two genera, Heliophrya and Cyclophrya, was previously assigned to Evaginogenida. There is now sufficient evidence, however, that the type genus Heliophrya reproduces by endogenous budding, which corresponds to the definitive feature of Endogenida. In line with this and with the support of molecular phylogenetic analyses, we therefore transfer the family Heliophryidae with the type genus Heliophrya to Endogenida. The other genus, Cyclophrya, still remains in Evaginogenida because of its evaginative budding. Therefore, combined with morphological and phylogenetic analysis, Cyclophyidae are reactivated, and it belongs to Evaginogenida.

10.
BMC Microbiol ; 20(1): 297, 2020 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-33008292

RESUMEN

BACKGROUND: Heterotrichous ciliates are common members of microeukaryote communities which play important roles in both the transfer of material and the flow of energy in aquatic food webs. This group has been known for over two centuries due to their large body size and cosmopolitan distribution. Nevertheless, species identification and phylogenetic relationships of heterotrichs remain challenging due to the lack of accurate morphological information and insufficient molecular data. RESULTS: The morphology and phylogeny of two heterotrichous ciliates, namely Gruberia foissneri spec. nov. and Linostomella vorticella (Ehrenberg, 1833) Aescht in Foissner et al., 1999, were studied using rigorous methods (living morphology, stained preparations, and small subunit rDNA sequence data). Gruberia foissneri spec. nov. is morphologically very similar to G. uninucleata Kahl, 1932, however, it can be distinguished from the latter by having more ciliary rows (about 32 vs. about 20) and macronuclear shape (sausage-shaped vs. ellipsoid). Based on a combination of previous and present studies, an improved diagnosis of L. vorticella is supplied and several taxonomic anomalies are clarified. In addition, phylogenetic analyses based on SSU rDNA sequence data support the generic assignment of these two species. CONCLUSIONS: Modern ciliate taxonomy should be performed by means of detailed living observation, stained preparations and molecular information. For those species that have been reported in previous studies, it is necessary to provide as much useful information as possible using state-of-the-art methods in order to resolve taxonomic anomalies.


Asunto(s)
Cilióforos/genética , ARN Ribosómico 18S/genética , Organismos Acuáticos , China , Cilióforos/clasificación , Cilióforos/citología , Cilióforos/ultraestructura , Filogenia
11.
Huan Jing Ke Xue ; 41(7): 3186-3193, 2020 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-32608891

RESUMEN

In this study, a cascaded watershed system in the Poyang Lake area was selected as the study site, which ranged from the primary tributaries to the lake area (Xiangxi River→Jiazhu River→Ganjiang River→Poyang Lake). The aims of the study were to monitor the P wet deposition and runoff process in the Poyang Lake area and discuss the P transport characteristics at the multi-scale watershed and its impact on phytoplankton community structure in the Poyang Lake. The results showed that the P concentration in the Poyang Lake area exhibited significant seasonal changes. Apart from the Xiangxi River watershed, the concentrations of total phosphorus (TP), dissolved total phosphorus (DTP), and orthophosphate(PO43-) were higher in the low flow period than in the high flow period at other watersheds. There was a significant correlation between TP concentration and diatom density during the high flow period, and between TP concentration and cryptophyta during the low flow period. The order of the amounts of TP and PO43- transport by runoff under different rain intensities is as follows:light rain > moderate rain > heavy rain. There is a significant difference in the deposition flux between the wet season and the dry season with seasonal change, in which the flux during the wet years was about 2.8 times higher than in the dry years. The export flux of P was also shown to be higher in the high flow than in the low flow period. As watershed size increased, the contribution rate of P export did not increase, indicating that P transported at different scales was not the main source of P in each watershed.

12.
Materials (Basel) ; 13(13)2020 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-32610541

RESUMEN

: This article introduces the effect of tempered 5140 alloy steel commonly used in engineering on its structure and mechanical properties under the action of proton irradiation. In the present study, the irradiation energy of 160 keV is applied to experimentally investigate the proton irradiation with different cumulative fluences on the tempered 5140 alloy steel. The effect of the cumulative fluence of the proton irradiation on the microstructure evolution of tempered 5140 alloy steel is studied through transmission electron microscopy. Moreover, the morphology of the tensile fracture is analyzed by scanning electron microscope. The effect of the cumulative fluence of the proton irradiation on the nanomechanical properties of tempered 5140 alloy steel is investigated with a nanomechanical tester. It is found that the surface hardening effect formed by the proton irradiation damage causes the dislocation density in the structure near the tempered 5140 alloy steel surface layer and such effect increases as the proton irradiation cumulative fluence increases. The results obtained show that the yield and tensile strength of the tempered 5140 alloy steel increase slightly as the cumulative fluence of the proton irradiation increases. However, the corresponding elongation decreases. For a stable pressure load of the nanoindentation, the hardness of the nanoindentation of the tempered 5140 alloy steel increases as the proton irradiation fluence increases. However, the corresponding indentation depth decreases. Based on the obtained results, it is concluded that proton irradiation has no significant effect on the macro- and nanomechanical properties of the tempered 5140 alloy steel. This may be attributed to the low energy of the proton irradiation, and the resulting radiation damage only acts on the thin layer of the tempered 5140 alloy steel surface.

13.
Huan Jing Ke Xue ; 40(6): 2696-2704, 2019 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-31854661

RESUMEN

In this study, a connected waterflow watershed system in the Poyang Lake area was selected as the study site, which ranged from the primary tributary to the lake area (Xiangxi River Jiazhu River Ganjiang River Poyang Lake). The aims of the study were to monitor different forms of C and N and evaluate the transport flux of C and N, and then, the transport mechanisms of C and N and the variation characteristics of water quality parameters in Poyang Lake were discussed, with the intent of providing a scientific basis for the comprehensive management of watershed health within the Poyang Lake Basin ecosystem. The main results were as follows. ① The concentrations of C and N in the Poyang Lake watershed exhibited significant seasonal changes, wherein the TIC, TOC, and TC concentrations in the Poyang Lake Basin were higher in the wet season than those in the dry season, and the NO3--N and DTN concentrations were higher in the dry season than those in the wet season. The main reason for the increase of TC in the wet season was the increase of TIC. Most of the TN in the wet season was transported by non-dissolved forms of N, while the TN in the dry period mostly was transported by DTN, and the DTN was mostly in the form of NO3--N. ② The C and N transport fluxes in the Poyang Lake watershed also showed significant seasonal variation. The C transport flux of Xiangxi River was lower during the wet season than that during the dry season, and the C transport flux of Jiazhu River and Ganjiang River was higher during the wet season than that during the dry season. The various forms of N transport flux in Xiangxi River, Jiazhu River, and Ganjiang River watershed were higher in the wet season than those in the dry season. There was a very significant positive correlation between the flux and runoff at the 99% confidence level. ③ The COND, TDS, and pH in the Poyang Lake watershed were lower during the wet season than those during the dry season, while the ORP in the wet season was higher than that in the dry season.

14.
J Eukaryot Microbiol ; 66(6): 925-936, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31112318

RESUMEN

Ampullofolliculina Hadzi, 1951 is a monotypic genus, the only species being A. lageniformis which was first discovered in estuarine habitats in the U.S. and has never been redescribed. In the present study, we investigated the taxonomy and phylogeny of A. lageniformis Hadzi, 1951 based on analyses of a population collected from a brackish wetland in Ningbo, China. The main characteristics of this species are as follows: trophont about 450-700 µm long in vivo with two short, rounded peristomial lobes of equal size; lorica flask-shaped, transparent and smooth with a short, wide neck at the base of which two transparent valves are asymmetrically inserted; cortex with brownish to reddish cortical granules and greenish pigment granules; about 80 somatic kineties evenly arranged; moniliform macronucleus with 4-8 ellipsoidal nodules; swarmer dark green, vermiform in shape, about 200-350 µm long in vivo, with about 60 adoral membranelles and 85 somatic kineties, no mouth nor paroral membrane. Phylogenetic analyses inferred from SSU rDNA sequences show that A. lageniformis is closely related to Folliculina and Eufolliculina which nest within a large clade that comprises five families, i.e. Stentoridae, Blepharismidae, Fabreidae, Maristentoridae, and Folliculinidae.


Asunto(s)
Cilióforos/clasificación , China , Cilióforos/citología , Cilióforos/genética , ADN Protozoario/análisis , Humedales
15.
Mater Sci Eng C Mater Biol Appl ; 101: 92-102, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31029368

RESUMEN

In this work, microstructures and corrosion behaviors of novel ZrTiAl-χV (χ = 0, 1, 3, 5, 7 wt%) alloys have been investigated. Phase composition and microstructures of the specimens are characterized using X-ray diffraction, optical microscopy, scanning electron microscopy, and transmission electron microscopy. The results show that phase composition of the alloys change by α' → α″ → α″ + ßâ€¯â†’â€¯ß as V is added gradually. Meanwhile, the mean size of the α' phase, α″ martensite and ß phase decreases as V content increases. In order to test the corrosion performance of the specimens, potentiodynamic polarization tests in NaCl and HCl solutions and immersion tests in HCl solution are performed. Analysis of potentiodynamic potential curves indicates that corrosion potential increases and corrosion current density decreases with adding V content in the examined alloys. From the results of weight loss tests, it can be observed that the weight loss of the examined alloys decreases along with the increase of V content. In addition, when the content of V is added from 3 to 7 wt%, the metastable corrosion pits are replaced with the stable corrosion pits. The phase composition as well as the grain size can be identified as the main factor affecting the corrosion performance of the alloys.


Asunto(s)
Aleaciones/química , Corrosión , Electroquímica , Factores de Tiempo , Difracción de Rayos X
16.
Environ Sci Pollut Res Int ; 25(21): 20899-20910, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29766422

RESUMEN

In karst areas, rock dissolution often results in the development of underground networks, which act as subterranean pathways for rapid water and nutrient (and possibly soil) loss during precipitation events. Loss of soluble nutrients degrades surface soils and decreases net primary productivity, so it is important to establish flow pathways and quantify nutrient loss during rainfall events of different magnitudes. We conducted a simulated rainfall experiment in karst and nonkarst areas to compare the concentration of nutrients in surface and subsurface flow water and effects on soil alkalinity in three lithologic soil formations under five different rainfall intensity treatments. Compared with the nonkarst area, the runoff in subsurface flows and the proportion of nutrient loss in the subsurface flow are larger in the karst area and less affected by rain intensity. The maximum loss loads of calcium (Ca2+) and magnesium (Mg2+) ions were 32.9 and 19.8 kg ha-1, respectively. With the estimate of base cation loss loads in the China southern karst area under the rainfall intensity of 45 mm h-1, more than 80% of the base cation loss load occurred in the limestone karst area. Although the alkalinity leaching value in nonkarst was similar to that in the karst area under simulated rainfall conditions, its impact on the ecological environment was quite different.


Asunto(s)
Agua Dulce/química , Sedimentos Geológicos/química , Agua Subterránea/química , Lluvia , Suelo/química , Movimientos del Agua , Calcio/análisis , Cationes/análisis , China , Clima , Magnesio/análisis , Modelos Teóricos , Potasio/análisis , Sodio/análisis
17.
Beilstein J Nanotechnol ; 9: 789-800, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29600140

RESUMEN

In this paper, an efficient method to produce a ZnO/BiOI nano-heterojunction is developed by a facile solution method followed by calcination. By tuning the ratio of Zn/Bi, the morphology varies from nanoplates, flowers to nanoparticles. The heterojunction formed between ZnO and BiOI decreases the recombination rate of photogenerated carriers and enhances the photocatalytic activity of ZnO/BiOI composites. The obtained ZnO/BiOI heterostructured nanocomposites exhibit a significant improvement in the photodegradation of rhodamine B under visible light (λ ≥ 420 nm) irradiation as compared to single-phase ZnO and BiOI. A sample with a Zn/Bi ratio of 3:1 showed the highest photocatalytic activity (≈99.3% after 100 min irradiation). The photodegradation tests indicated that the ZnO/BiOI heterostructured nanocomposites not only exhibit remarkably enhanced and sustainable photocatalytic activity, but also show good recyclability. The excellent photocatalytic activity could be attributed to the high separation efficiency of the photoinduced electron-hole pairs as well as the high specific area.

18.
Materials (Basel) ; 11(4)2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29601500

RESUMEN

In this work, we investigate the mechanical properties of an annealed high strength Ti-20Zr-6.5Al-4V alloy in uniaxial tensile tests in different directions. The results show that the alloy exhibits obvious anisotropic ductility in different directions, while the tensile strength of the alloy remains almost unchanged. This phenomenon is closely related to α laths with similar orientations along the prior-ß grain boundaries. These α laths significantly affect the initiation and propagation of cracks when the alloy reaches its yield limit, thereby affecting the ductility of the alloy, such that it exhibits anisotropic ductility.

19.
J Nanosci Nanotechnol ; 17(2): 1217-224, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29683295

RESUMEN

Nickel-tungsten (Ni­W) coatings were fabricated by electrodeposition method with varying quantities of sodium dodecyl sulphate and sodium bromide to examine the effects of the aforesaid additives on the coatings. The obtained nanocoatings were studied by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and hardness tester. The hardness, tungsten content and grain size attained a maximum value at current density of 0.15 A/cm²,0.1 A/cm² and 0.1 A/cm², respectively. There was a pronounced impact of both the additives on the microstructure and morphology of the coatings. According to results, there are considerable difference in terms of the impact caused by the additives to the tungsten content, hardness and grain size of the coatings. The obtained results suggest that hardness of coatings is mainly contributed by W content in the deposits.

20.
Dongwuxue Yanjiu ; 37(3): 176-85, 2016 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-27265656

RESUMEN

Two colepid ciliates, Coleps amphacanthus Ehrenberg, 1833 and Levicoleps biwae jejuensis Chen et al., 2016, were first recorded in China. Their living morphology, infraciliature and small subunit (SSU) rRNA gene sequences were determined using standard methods. The improved diagnosis of Coleps amphacanthus is as follows:cell size about 100×50 µm in vivo, barrel-shaped; 22-28 ciliary rows each composed of about 14-21 monokinetids and two perioral dikinetids; 5-10 caudal cilia; and one terminal contractile vacuole. Levicoleps biwae jejuensis was also investigated, with an improved diagnosis given based on previous and present work. The phylogenetic analyses based on SSU rRNA gene sequences revealed that all Coleps species were grouped together, except for Coleps amphacanthus, which was grouped into a clade of the genus Levicoleps.


Asunto(s)
Cilióforos/clasificación , Cilióforos/citología , Filogenia , China , Cilióforos/genética , ARN Ribosómico/genética , Análisis de Secuencia de ARN
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