61 research outputs found
First molecular evidence of hybridization in endosymbiotic ciliates (Protista, Ciliophora)
Hybridization is an important evolutionary process that can fuel diversification via formation of hybrid species or can lead to fusion of previously separated lineages by forming highly diverse species complexes. We provide here the first molecular evidence of hybridization in wild populations of ciliates, a highly diverse group of free-living and symbiotic eukaryotic microbes. The impact of hybridization was studied on the model of Plagiotoma, an obligate endosymbiont of the digestive tube of earthworms, using split decomposition analyses and species networks, 2D modeling of the nuclear rRNA molecules and compensatory base change analyses as well as multidimensional morphometrics. Gene flow slowed down and eventually hampered the diversification of Lumbricus-dwelling plagiotomids, which collapsed into a single highly variable biological entity, the P. lumbrici complex. Disruption of the species boundaries was suggested also by the continuum of morphological variability in the phenotypic space. On the other hand, hybridization conspicuously increased diversity in the nuclear rDNA cistron and somewhat weakened the host structural specificity of the P. lumbrici complex, whose members colonize a variety of phylogenetically closely related anecic and epigeic earthworms. By contrast, another recorded species, P. aporrectodeae sp. n., showed no signs of introgression, no variability in the rDNA cistron, and very high host specificity. These contrasting eco-evolutionary patterns indicate that hybridization might decrease the alpha-diversity by dissolving species boundaries, weaken the structural host specificity by broadening ecological amplitudes, and increase the nuclear rDNA variability by overcoming concerted evolution within the P. lumbrici species complex
Integration of residents' experiences into economic planning process of coastal villages: Evidence from the Greater Hangzhou Bay Rim Area
Public value is gaining prominence from both academics and politicians with regards to China's rural development. However, rural planning authorities and practitioners showed limited confidence on public, which manifests as few public perceptions were integrated into the planning documents. This study explores the potential role of residents' experiences in illustrating local economic development within the context of coastal villages in which economic and industries are rapidly transforming. Two case studies from within the locale of the Greater Hangzhou Bay Rim Area are used in this article to examine the gap between residents' experiences and the actual economic development that has occurred. The main findings suggest that rural residents can directly reflect upon both current and historic trends of local economic development. Moreover, household income satisfaction (HIS) is a comprehensive notion of residents' experiences, and indicates social and economic sustainability of industrial transformation, or "thriving business", that have been highlighted in coastal villages. Public experiences could therefore act as a valid and accessible evidence for planners in rural economic planning in China and other developing countries
Loss of miR-638 in vitro promotes cell invasion and a mesenchymal-like transition by influencing SOX2 expression in colorectal carcinoma cells
BACKGROUND: Colorectal carcinoma (CRC) is a major cause of cancer mortality. The aberrant expression of several microRNAs is associated with CRC progression; however, the molecular mechanisms underlying this phenomenon are unclear. METHODS: miR-638 and SRY-box 2 (SOX2) expression levels were detected in 36 tumor samples and their adjacent, non-tumor tissues from patients with CRC, as well as in 4 CRC cell lines, using real-time quantitative RT-PCR (qRT-PCR). SOX2 expression levels were detected in 90 tumor samples and their adjacent tissue using immunohistochemistry. Luciferase reporter and Western blot assays were used to validate SOX2 as a target gene of miR-638. The regulation of SOX2 expression by miR-638 was assessed using qRT-PCR and Western blot assays, and the effects of exogenous miR-638 and SOX2 on cell invasion and migration were evaluated in vitro using the HCT-116 and SW1116 CRC cell lines. RESULTS: We found that miR-638 expression was differentially impaired in CRC specimens and dependent on tumor grade. The inhibition of miR-638 by an antagomiR promoted cell invasion and a mesenchymal-like transition (lamellipodium stretching increased and cell-cell contacts decreased, which was accompanied by the suppression of the epithelial cell marker ZO-1/E-cadherin and the upregulation of the mesenchymal cell marker vimentin). A reporter assay revealed that miR-638 repressed the luciferase activity of a reporter gene coupled to the 3′-untranslated region of SOX2. miR-638 overexpression downregulated SOX2 expression, and miR-638 inhibition upregulated SOX2 expression. Moreover, miR-638 expression levels were correlated inversely with SOX2 mRNA levels in human CRC tissues. The RNAi-mediated knockdown of SOX2 phenocopied the invasion-inhibiting effect of miR-638; furthermore, SOX2 overexpression blocked the miR-638-induced CRC cell transition to epithelial-like cells. CONCLUSIONS: These results demonstrate that the loss of miR-638 promotes invasion and a mesenchymal-like transition by directly targeting SOX2 in vitro. These findings define miR-638 as a new, invasion-associated tumor suppressor of CRC
Study on recovery of copper and zinc from cyanide lean solution in a smelting company
In the process of cyanidation of gold concentrate from a smelting company, the content of copper and zinc in the liquid gradually increased. In production, acidizing process is used to treat the lean solution from high copper concentrate, and mixed products containing copper, zinc and other metals are produced. In this paper, the pH value of zinc precipitation is 6.0 and the pH value of copper precipitation is 3.0 through theoretical calculation and experiment. The separation of copper and zinc in the lean solution is realized successfully. The zinc product with grade of 42.97% and the copper product with grade of 58.33% are produced
Experimental study on thiosulfate leaching of gold from a high copper gold concentrate
The conventional cyanide leaching process is used to extract gold from a high copper gold concentrate. Because the copper associated minerals consume sodium cyanide in large quantities, the cost of the reagents is high and the economic benefit is not ideal. At the same time, a large number of cyanide tail slag are produced, which brings a series of environmental problems. In order to solve the environmental problems caused by excessive sodium cyanide consumption and cyanogen slag, the feasibility of leaching gold by thiosulfate in copper ammonia system was studied. The gold leaching rate of thiosulfate was increased to more than 90% by using the direct thiosulfate leaching process and pretreatment thiosulfate leaching process, which was close to the gold leaching index of sodium cyanide at the production site
Feasibility Study for the Fast Periodic Pulsed Reactor with UO2 Fuel
<jats:p>In order to study the feasibility of the fast periodic pulsed reactor with UO<jats:sub>2</jats:sub> as fuel (abbreviated as FPPRU), the core models with different load schemes are designed. Neutronic characteristics of two typical design schemes are compared, and the better design scheme is determined. The critical search method is established for analyzing the reactor dynamics. Furthermore, the theoretical estimation formulas are derived to study the factors affecting the reactor dynamics clearly and intuitively. The reactor dynamics of the fast periodic pulsed reactor with UO<jats:sub>2</jats:sub> and PuO<jats:sub>2</jats:sub> as fuel are compared. The thermal hydraulic characteristic of FPPRU is studied with the sub-channel model. The results show that the design scheme of the FPPRU meets the demand of neutronics and thermal hydraulics safety. Meanwhile, the pulse parameter quality of the FPPRU with UO<jats:sub>2</jats:sub> as fuel is not as good as that of IBR-2 with PuO<jats:sub>2</jats:sub> as fuel.</jats:p>
Protoptychostomum simplex Raabe 1949
Protoptychostomum simplex (André, 1915) Raabe, 1949 (Figs 1A–I, 2A–I; Table 1) Synonymy: Anoplophrya simplex André 1915: 102, fig. 1, host: not specified Lumbricidae. Ptychostomum simplex Heidenreich (1935: 530–531, fig. 3) transferred A. simplex to Ptychostomum and described the living morphology of a German population, host: ‘ Allolobophora caliginosa ’. Possibly a misidentified Protoptychostomum davidis (Rees, 1962), whose type host is ‘ A. caliginosa ’. Protoptychostomum simplex. Raabe (1949: 36, fig. 5) transferred A. simplex to Protoptychostomum, host: ‘ Eiseniella tetraedra f. tipica (Savigny)’. Meier (1954: 234–236, fig. 15) described the morphology of a German population (Mannhof), host: E. tetraedra. Kaczanowski (1961: 257–272, figs 1–7, plate I) studied morphology, morphogenesis, and silver line system of a Polish population (Lubkowo), host: E. tetraedra. Raabe (1972: 129–130, fig. 5A–E) revised the species. a Data based on protargol-impregnated specimens.Measurements in μm. Abbreviations:CV,coefficient of variation (%); M, median;Max,maximum; Mean, arithmetic mean;Min, minimum; N, number of individuals investigated;SD, standard deviation. Improved diagnosis (includes all information known): Body size about 85–200 × 50–90 µm in vivo. Body broadly ovoid to ovoid, with anterior end more narrowly rounded than posterior one. Anterior sucker forms an inverted, widened, V-shaped paưern, sucker arms about 15–28 µm long forming an angle of about 97°. Nuclear apparatus situated below midbody, composed of one macronucleus and two micronuclei. Two contractile vacuoles situated less of cell’s midline, anterior and posterior to macronucleus. On average, 48 less and 78 right meridional ciliary rows. Oral ciliature consists of a paroral membrane and two membranelles; paroral and both membranelles begin near ventral margin of posterior body side, extend along whole posterior body end to plunge into infundibulum, where they describe two complete turns of a spiral. Type locality: Lake Maggiore (Fr. Lac Majeur). The lake and its shoreline are divided between the Italian regions of Piedmont and Lombardy and the Swiss canton of Ticino. Type host: Not provided in the original paper (André 1915). All reliable records (Raabe 1949, 1972; Meier 1954; Kaczanowski 1961; present study) come only from the semi-aquatic Eiseniella tetraedra (Savigny, 1826). ND1 and COI sequences of Slovak E. tetraedra specimens, which harboured P. simplex, have been deposited in GenBank under the following accession numbers: OP752211–OP752212 and OP755297–OP755298, respectively. Type material: Deposition of type material not mentioned in the original paper (André 1915) and is thus probaby unavailable. Voucher material: A DNA sample of a voucher specimen (CVsk 190 ET) has been deposited in the Natural History Museum, Vajanského nábrežie 2, 810 06 Bratislava, Slovakia (ID Collection Code 01426283). Paratype slides containing protargol-impregnated specimens (reg. no. 2023/1–4- ZTY) have been deposited at the Department of Zoology, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia. Gene sequences: The 18S rRNA gene, ITS region-28S rRNA gene, and 16S rRNA gene sequences of the voucher specimen CVsk 190 ET have been deposited in GenBank under the following accession numbers: OP755196, OP755170 and OP755221, respectively. Etymology: The Latin adjective simplex (simple) refers to the simple nuclear and contractile vacuole apparatus. Description: Two populations of P. simplex were found. Their conspecificity was confirmed by 18S, ITS region-28S, and 16S rRNA gene sequences. However, the description is based only on the populations from the riparian zone of the Kráľov potok stream in the village of Plavecké podhradie, Malacky district, Slovakia. Body size about 85–175 × 55‒90 µm, usually 130 × 75 µm, as calculated from some in vivo measurements and the morphometric data adding 20% preparation shrinkage (Table 1). Body broadly ovoid to ovoid, with anterior end more narrowly rounded than posterior one; length:width ratio 1.4–2.2:1, near 2.0:1 both in vivo and in protargol preparations; distinctly laterally flaưened (Figs 1A, B, D–I, 2C, D; Table 1). Sucker occupies anterior body pole, more or less delimited by inconspicuous concavities on lateral body sides; forms an inverted, widened, V-shaped paưern. Angle formed by sucker arms about 97° on average; both arms of similar length, i.e. about 15–28 µm long asser protargol impregnation (Figs 1A, B, D, F–I, 2C; Table 1). Sucker unciliated and densely doưed by regularly arranged rows of granules; individual granules sometimes weakly impregnate with the protargol method used (Fig. 2A, C). No skeletal fibres developed. Nuclear apparatus situated below midbody, i.e. usually about 50 µm apart from anterior body end asser protargol impregnation; invariably composed of one macronucleus and two micronuclei. Macronucleus located in posterior body half, globular to broadly ellipsoidal, and 22–44 × 14–35 µm in size asser protargol impregnation; nucleoli small and more or less globular, evenly distributed over macronucleus. Micronuclei close to each other; consistently aưached to right side of macronucleus at its midportion; about 2.6 µm in diameter asser protargol impregnation; difficult to recognize in vivo, faintly and unevenly impregnated with the protargol method used (Figs 1A, B, D, F–I, 2C–E; Table 1). Invariably two contractile vacuoles situated less of the midline of the cell, anterior and posterior to macronucleus; excretory pores not observed either in vivo or asser protargol impregnation (Fig. 1A, I). Cortex flexible; not, or only slightly, furrowed by ciliary rows; no specific granules recognizable in vivo but faintly impregnated and irregularly scaưered granules sometimes recognizable in protargol preparations (Fig. 2H). Cytoplasm colourless; 5.5 µm-sized food vacuoles together with a vast number of densely spaced granules (about 0.8–1.0 µm in diameter) occupy an irregular area between posterior end of macronucleus and peristome (Figs 1A, 2B). Swims moderately fast, rotating about main body axis; dies in about half an hour asser extraction from host. Somatic ciliature holotrichous and composed of monokinetids. Somatic cilia about 9 µm long in vivo, narrowly arranged in an average of 48 less and 78 right meridional rows (Table 1). Less ciliary rows start below posterior margin of sucker, while right ciliary rows begin at anterior margin of sucker. Individual ciliary rows densely spaced, i.e. approximately 2 µm apart from each other; frequently with irregularities on both less and right body side, e.g. some rows shortened anteriorly or posteriorly, and/or with short breaks causing a swap between two adjacent and sometimes even more distant ciliary rows (Figs 1D, E, 2G). No secant system recognizable in laterally oriented cells, possibly also due to slightly more irregular arrangement of basal bodies at posterior body pole. Oral apparatus located at posterior body pole and composed of an outer peristomial region and an inner infundibular part. Peristomial region follows the curvature of posterior body end, oriented perpendicularly to anteroposterior body axis, and approximately 32 µm wide asser protargol impregnation (Table 1); outer oral cilia about 7 µm long in vivo. Infundibulum 12.2–24.1 µm long in protargol preparations, describing two complete turns of a spiral; infundibular cilia about 8.5 µm long in vivo, form nice metachronal waves. Oral ciliature consists of a paroral membrane and only two membranelles (M1 and M2). Paroral membrane and both membranelles begin near ventral margin of posterior body side, extend along whole posterior body end to plunge into infundibulum where they form a helix-like paưern. Membranelle M1 located anteriormost, made up of two rows of basal bodies, not segmented. Membranelle M2 runs beside M1 and hence both membranelles appear as a single ciliary structure, composed of only a single row of basal bodies, not segmented. Both membranelles anteriorly bent forming an inverted J-shaped paưern. Paroral membrane located posteriormost, distinctly separated from M1 and M2, consists of two rows of kinetosomes, not segmented and not hook-like curved anteriorly. Cytopharynx originates at proximal end of paroral membrane and both membranelles; runs towards anterior body end almost in parallel with main body axis; forms a slender, 8.0–14.3 µm-long funnel faintly impregnating with the protargol method used (Figs 1A–D, F–I, 2B–F, I; Table 1).Published as part of Obert, Tomáš, Zhang, Tengyue & Vďačný, Peter, 2023, The search finds an end: the morphologically chimeric hysterocinetids belong to the subclass Hymenostomatia (Ciliophora: Oligohymenophorea), pp. 97-123 in Zoological Journal of the Linnean Society 199 (1) on pages 99-103, DOI: 10.1093/zoolinnean/zlad023, http://zenodo.org/record/832624
Effect of amblyopia treatment on macular microvasculature in children with anisometropic amblyopia using optical coherence tomographic angiography
Abstract To measure the retinal microvascular density in patients with anisometropic amblyopia using optical coherence tomographic angiography (OCTA) and to evaluate the effects of successful amblyopia treatment on microvasculature in retina. 59 children (5–12 years old) including 22 newly diagnosed unilateral anisometropic amblyopia, 16 recovered unilateral anisometropic amblyopia, and 21 control children were imaged with OCTA using 6 × 6-mm macular scan pattern. Vessel densities of the superficial capillary plexus (SCP), the deep capillary plexus (DCP), and the overall macular thickness were acquired and compared among the three groups. After adjustment for axial length, the amblyopia group showed lower macular vessel density in the SCP (P = 0.005) and in the DCP (P = 0.004) compared with that of the control group. However, for the recovered amblyopia group, no difference of vessel density was found when compared with the control group in both the SCP (P = 0.548) and the DCP (P = 0.124). No difference of the mean macular thickness was found among three groups (P ≥ 0.15). Children with anisometropic amblyopia have reduced macular vessel density in OCTA, while no difference of macular vessel density was found between the recovered amblyopic and control eyes. Macular thickness showed no difference in anisometropic amblyopia and remained unchanged after amblyopic treatment
The impact of confirmed cases of COVID-19 on residents’ traditional Chinese medicine health literacy: A survey from Gansu Province of China
Effects of Different Surface Heat Transfer Coefficients on Predicted Heating and Cooling Loads towards Sustainable Building Design
The transfer of surface heat between a building and the outdoor environment is the energy transfer channel and it is important for the energy efficiency of buildings. Early stage building design is a critical stage and it can directly determine the energy consumption by a building. Therefore, selecting appropriate surface heat transfer coefficients (SHTCs) is a key issue in building energy consumption prediction. In this study, EnergyPlus was employed to investigate the building load in Chinese cities with different SHTCs: (1) constant SHTCs based on national standards; and (2) dynamically changing SHTCs based on the Thermal Analysis Research Program (TARP). Based on investigations of the hourly load, daily cumulative load in a typical day, and annual cumulative load with different SHTCs, corrections for the annual cumulative load were obtained according to the relative deviations between the results produced with the TARP model and traditional SHTCs. The greatest relative deviations were 67.5% and 25.3% for the building shape factor φ = 0.49 and 0.29 in Lhasa. The relative deviations were 13.3% and 12.0% for φ = 0.49 in Xi’an and Beijing, respectively. Corrections were not essential for other conditions because the relative deviations were lower than 5.0%. Considering the current characteristics of engineering calculations and the need to obtain more accurate design results, dynamically changing SHTCs should be applied. These correction factors can obtain more accurate results for the current building energy efficiency system with traditional SHTCs
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