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Automatic building detection from remote sensing images holds significant applications in various domains, including cartography, land-use change detection, urban planning, and 3D intelligent city construction. Driven by the innovation of deep learning technology, convolutional neural networks (CNNs) have emerged as a powerful framework for automatic interpretation, exhibiting hierarchical feature generation and robust representation for building extraction. However, the inherent computational limitations of convolutional operators hinder the acquisition of an effective global receptive field. Recent advancements in deep learning have witnessed the adoption of the multi-head self-attention (MHSA) mechanism by Transformer, presenting the superiority of global context construction. Nonetheless, this network structure encounters difficulties in effectively modelling two-dimensional spatial structure features with scale variation in semantic segmentation and often has huge parameters with high algorithm complexity. To address the above problems, this paper proposed a hybrid deep neural network synergistically harnessing the superiority of CNN and Transformer to extract buildings from remote sensing images. Meanwhile, an improved MHSA mechanism is developed to facilitate the construction of multiscale global representations, concurrently reducing computational complexity. Furthermore, the cross-level MHSA modules the semantic correlation between the deep and shallow-level features to refine spatial fine-grained information. The proposed method was comprehensively evaluated on two building datasets via quantitative analysis and visualization. The experimental results confirmed that the developed network and modules outperform other state-of-the-art methods and can effectively improve the accuracy (93.4% F1-score on the WHU dataset, 89.38% F1-score on the CAMB dataset) with high efficiency for building extraction. [ABSTRACT FROM AUTHOR]

This article presents a novel design methodology for asymmetric coupled line passive devices. Based on the extraction of distributed parameters of coupled lines from S-parameters, we re-derived modal characteristic parameters and Z matrix of four-port asymmetric coupled lines in inhomogeneous mediums. Then, Z matrices of ten two-port asymmetric coupled line circuits are derived and their frequency responses are analyzed. Inspired by the image parameter method, image impedances are adopted for two-port device designs. Data diagrams which connect geometric parameters with impedances are provided to simplify design processes. Two impedance transformers utilizing the open-ended and short-ended coupled line circuits, respectively, producing high transforming ratios of 100 (50 Ω to 0.5 Ω) and 40 (50 Ω to 2000 Ω) are fabricated to verify the proposed analysis and design method. Excellent agreement between the simulation and measurement result proves the unique superiorities of asymmetric coupled lines with better initial values. [ABSTRACT FROM AUTHOR]

Streptococcus mutans (S. mutans) is a potential pathogenic bacteria of dental caries. However, the level of S. mutans is low in some children with severe early childhood caries (SECC) To evaluate the effect of S. mutans level on dental microbiome and cariogenesis. The oral microbiota was compared between caries-free group (CF) and SECC group.16S rRNA gene sequencing was used for S. mutans level bacterial community analysis. The candidate bacteria that were closely related with S. mutans abundance were identified and confirmed by absolute quantitative real-time PCR in clinical dental plaque samples from CF and SECC groups. Through in-depth analysis of dental plaque microorganism, Leptotrichia, Selenomonas and Prevotella_7 were found in the S. mutans-low group (p < 0.05) and Porphyromonas, Selenomonas_3 were found in the S. mutans-high group (p < 0.05). Through quantitative real-time PCR, Leptotrichia, Selenomonas and Prevotella_7 were identified as the potential biomarkers of SECC when S. mutans was at a low level. Leptotrichia, Selenomonas and Prevotella_7 are identified as potential biomarkers in SECC with a low abundance or without S. mutans. Our study may shed light on the understanding of caries occurrence in SECC with low abundance of S. mutans. S. mutans, Streptococcus mutans; CF, caries-free; SECC, severe early childhood caries; ECC, early childhood caries; rRNA, ribosome RNA; qPCR, Quantitative real-time PCR; OTUs, operational taxonomic units; ANOVA, analysis of variance; LDA, Linear discriminant analysis; LEfSe, Linear discriminant analysis effect size; COG, Groups of proteins; NMDS, Non-MetricMulti-Dimensional Scaling; IL-1β, interleukin −1β; IL-6, interleukin-6; IL-8, interleukin-8; IL-10, interleukin-10. [ABSTRACT FROM AUTHOR]

Post-collisional K-rich magmatic rocks of the Qinghai–Tibet Plateau provide important information for understanding the continental collision and uplift of this plateau during the Cenozoic. However, the source of these K-rich rocks is still debated, and limited investigations have been conducted in the western Kunlun Mountains (WKM) in the northwestern margin of the plateau. In this paper, we present geochemical, geochronological, and Sr–Nd–Hf isotope data for Quanshuigou post-collisional K-rich igneous rocks from the WKM. Geochronological results show that these rocks were emplaced during two stages: (1) ca. 5.3 Ma, as an intrusive suite of granite porphyries; and (2) ca. 4.8 Ma, as a suite of shoshonites. These rocks are enriched in light rare earth elements (LREEs) and large-ion lithophile elements (LILEs), and depleted in heavy rare earth elements (HREEs) and high-field-strength elements (HFSEs). Compositions of the granite porphyries classify these rocks as high-K calc-alkaline peraluminous A-type granites. Combining the negative zircon εHf(t) values (−6.9 to −1.1) with Hf crustal model ages (TDM2) of 1.16–1.53 Ga and negative εNd(t) values (−5.31 to −4.96) with two-stage Nd model ages (TDM2) of 1.22–1.46 Ga, these signatures suggest that the granite porphyries most probably originated from partial melting of thickened lower crust with limited input of mantle-derived magmas. In contrast, the shoshonites have low SiO2 contents (50.84–53.94 wt.%), relatively high Mg# values (50–57), and εNd (t) values ranging from −6.18 to −5.34, with single-stage Nd model ages (TDM1) of 0.97–1.02 Ga. Our analyses show that the parental magma of the shoshonites probably formed by partial melting of EMII-type lithospheric mantle, with the addition of subducted and recycled oceanic sediments. Hence, we conclude that these granite porphyries and shoshonites formed in a post-collisional, extension-related geodynamic setting and that the melting was probably triggered by motion on the Altyn Tagh strike-slip fault system. [ABSTRACT FROM AUTHOR]

Caffeinated products are frequently consumed by women of childbearing age worldwide. It still unclear that whether maternal intake of caffeine associated with an increased risk of birth defects. We searched the databases of PubMed, Embase, the Cochrane Library, and Web of Science for eligible studies through July 2020. All studies examining the association between maternal consumption of caffeine or caffeinated products and birth defects were included. Twenty-nine studies were included in this meta-analysis. Among all the birth defects, maternal caffeine consumption was associated with a higher risk of cardiovascular defects, [odds ratio (OR) 1.17; 95% confidence interval (CI), 1.07–1.28], craniofacial defects (OR 1.09; 95% CI, 1.02–1.17), alimentary tract defects (OR 1.35; 95% CI, 1.16–1.56), and abdominal-wall defects and hernia (OR 1.13; 95% CI, 1.03–1.25). No association was found between maternal caffeine intake and musculoskeletal system defects, genitourinary system defects, nervous system defects, or chromosomal abnormalities. Meanwhile, all three of the caffeine consumption categories (low, moderate, and high) were associated with a higher risk of cardiovascular defects and alimentary tract defects. [ABSTRACT FROM AUTHOR]

Background: Morphine plays an irreplaceable role in relieving severe pain clinically, while long-term medication inevitably leads to drug resistance. MicroRNA (miR) 146a has been reported to be a negative regulator in the process of morphine-tolerance formation. This study aimed to investigate how miR-146a affects the development of morphine analgesic tolerance. Methods: The morphine-tolerance rat model was established by means of one-week continuous morphine administration. Paw withdrawal latency test was performed every day, and spinal cord samples were dissected on the seventh day for Q-PCR and Western blotting to detect the expression level of miR-146a, and IRAK1/TRAF6 participated in TLR4 signaling pathway. Results: The expression of miR-146 was significantly decreased in morphine-tolerant model. Also, overexpression of miR-146a reduced the resistance caused by morphine, followed by the down-regulation of IRAK1/TRAF6 in TLR4 pathway. The inhibition of miR-146a remarkably decreased paw withdrawal latency as well as increased the expression levels of TLR4 signaling pathway-related molecules, IRAK1 and TRAF6. Conclusion: This study suggests that miR-146a attenuates morphine tolerance by inhibiting the expression of IRAK1/TRAF6 in TLR4 pathway, which could provide an essential experimental basis for the settlement of morphine resistance-associated matters. [ABSTRACT FROM AUTHOR]

As an important predatory mite, Stratiolaelaps scimitus (Womersley) is commercially produced to control pests of edible fungi and greenhouse. In this study, the complete mitochondrial (mt) genome of S. scimitus was sequenced by Illumina HiSeq, which comparatively analysed all reported mt genome rearrangement of mesostigmatid species. The mt genome of S. scimitus was a typical circular molecule of 16,468 bp (GenBank: MK912042) and contained the complete set of 37 genes as other metazoan mitochondrial genomes. The AT-and GC-skew on the majority strand was −0.061 and 0.365, respectively, which were reversed compared to those found in most metazoan mitochondrial genomes. Like other mesostigmatid mites, many gene rearrangements occurred in the mt genome of S. scimitus. The six mesostigmatid families containing rearranged mt genomes were characterized by unique gene order, except Diplogyniidae and Parasitidae. Shared gene clusters were found in four mesostigmatid families (Laelapidae, Blattisociidae, Phytoseiidae, and Macrochelidae), indicating that they are synapomorphic for these families. These gene characters are valuable in phylogenetic analysis of relationships at different taxonomic levels. [ABSTRACT FROM AUTHOR]

Functional response of four stages (female, male, nymphs and larvae) of Cheyletus malaccensis Oudemans on Megoura japonica Matsumura nymph was examined at five constant temperatures (16, 20, 24, 28 and 32°C) and 75% relative humidity (RH). The results showed that the predation functional response of C. malaccensis on M. japonica was in accordance with the Holling II equation. Within the experimental temperature ranges, the control capacity (a/Th) of C. malaccensis at each stage on M. japonica increased along with the temperature, reaching its peak at 28°C. The predatory capacity of female was the highest, followed by male, while that of the larvae was the lowest. Under the conditions of fixed density of prey, the average predation gradually decreased as the density of the predators increased due to mutual competition and interference among the C. malaccensis population. The experimental results demonstrated that C. malaccensis preferred the larvae of M. japonica to the adults. [ABSTRACT FROM AUTHOR]

Blattisocius Keegan is a genus of predatory mites in the family Blattisociidae, with potential utility as biological control agents. In the present study, Illumina HiSeq was used to sequence the complete mt genome of B. keegani Fox. The mt genome of B. keegani was a circular DNA molecule of 17,314 bp. With a 1,935 bp-long non-coding region, it is the second largest mt genome in Acari. All 37 genes expected to be present in a standard metazoan mitogenome were identified in this genome. Phylogenetic analyses of 28 additional species of Acari were then performed based on the mt genome. Bayesian inference (BI) and Maximum likelihood (ML) algorithm were used to analyse the sequence data. Compared with Limulus polyphemus, rearrangements of 34 genes and changes of three genes orientation (trnE, trnF and trnS1) in B. keegani were observed. Additionally, the gene order of the six mesostigmata mites used in the study showed a lack of conserved gene blocks. BI and ML trees based on 13 protein-coding genes suggested that B. keegani was clustered with E. nicholsi and P. persimilis into a Phytoseioidea branch, which was consistent with the traditional classifications result. [ABSTRACT FROM AUTHOR]

In this paper, we report a soluble expression based on Escherichia coli and two-step purification of a novel thioredoxin-tagged chicken interferon-α fusion protein (Trx-rChIFN-α) by using pET32a(+) expression system. The mature ChIFN-α gene was amplified by Reverse transcriptase-polymerase chain reaction (RT-PCR) and subcloned into pET-32a (+) vector prior to transformation into Rosetta (DE3) competent cells. After IPTG induction, the recombinant fusion protein was expressed efficiently in the soluble fraction. The protein purification was performed by nickel affinity chromatography and DEAE anion exchange chromatography. The purified product has a purity of 95% with a yield of 47.3 mg/L of culture. The specific activity of the fusion protein reaches to 2.0 × 107 IU/mg as determined in the CEF/VSV titration system. After excision of the Trx tag by enterokinase, the remaining solo protein was confirmed as rChIFN-α protein by SDS-PAGE, N-terminal sequencing and mass spectrometry. The effects of this Trx-rChIFN-α fusion protein against H9N2 influenza virus infection were also evaluated in ovo. The results showed that the Trx-rChIFN-α protein could significantly reduce the hemagglutination titer of H9N2 virus, and the H9N2 viruses HA gene copy numbers. These findings will enable us to produce large amount and bio-active rChIFN-α protein for future applications. [ABSTRACT FROM AUTHOR]

Aleuroglyphus ovatus is a major mite pest of stored products worldwide, which can seriously impact human health and economic outcomes. Temperature has a great influence on the population dynamics of A. ovatus. Synthesis of heat shock protein (Hsp) is one of the protective mechanisms that enable mites to cope with heat stress. In this study, two full-length cDNA sequences of AoHsp70-1 and AoHsp70-2 from A. ovatus were cloned and expressed. AoHsp70-1 and AoHsp70-2 gene sequences were 2307 and 2623 base pairs (bp) in length, respectively. The open reading frames of AoHsp70-1 and AoHsp70-2 were 1974 and 1923 bp, which encoded 657 and 640 amino acid residues, respectively. The deduced amino acid sequences of AoHsp70-1 and AoHsp70-2 demonstrated their high homology with other mites and insects. The mRNA expression levels of AoHsp70 at different developmental stages and under temperature stress were evaluated. The obtained results showed that the expression levels of Hsp70 differ between each developmental stage (i.e. eggs, larvae, nymphs, and female adults) of A. ovatus. Different responses of AoHsp70-1 and AoHsp70-2 to temperature stress suggested that the deduced amino acids of AoHsp70-1 and AoHsp70-2 were constitutive and inducible proteins, respectively. The inducible AoHsp70-2 may play a role in promoting temperature resistance in A. ovatus. The increased expression levels of AoHsp70-2 under heat stress indicated that A. ovatus was more sensitive to high temperature. The findings from this study may provide insight into the mechanisms underlying heat stress resistance in A. ovatus. [ABSTRACT FROM AUTHOR]

The Mesozoic Xigaze ophiolite is a key to understanding the tectonic evolution of the Yarlung Zangbo suture zone. Although many studies have been reported, the formation age and petrogenesis of the Xigaze ophiolite remain controversial. In this paper, new geochronological and geochemical data for mafic dikes (diabase, dolerite), lavas, and gabbros of the Xigaze ophiolite are provided to constrain the origin of the Xigaze ophiolite. Combined with previous studies, three new zircon U-Pb ages of samples from two gabbro and one dolerite samples show that the Xigaze ophiolite was produced at two distinct stages of 174-149 Ma and 137-123 Ma. Whole-rock geochemical data indicate that these rocks exhibit N-MORB-like features, but the gabbros are more depleted in trace elements and belong to cumulates. Geochemical characters, combined with their positive εNd(t) values (+3.2 to +9.6), suggest that these samples originated from depleted mantle sources with minor influence of slab-derived fluids. Considering the previous studies on the Yarlung Zangbo suture zone, the Xigaze ophiolite was likely generated in an active continental margin fore-arc basin with a multistage model associated with the northward subduction of the Yarlung Zangbo Neo-Tethys Ocean beneath the Lhasa terrane. The Middle-Late Jurassic ophiolitic massifs (174-149 Ma) were produced as the result of slab rollback and were followed by subsequent slab break-off at ~ 150 Ma. The fore-arc lithosphere may be frozen at ~150-137 Ma, consistent with the termination of the Gangdese arc magmatism during this period. The Early Cretaceous ophiolitic massifs (137-123 Ma) were developed in relation to the reinitiation of the Neo-Tethyan oceanic lithosphere subduction, the retreat of the subduction zone, and the creation of a fore-arc basin with strong hyperextension in a new cycle. [ABSTRACT FROM AUTHOR]

The Jurassic-Early Cretaceous Yilashan mafic-ultramafic complex is located in the middle part of the Bangong-Nujiang suture zone, central Tibet. It features a mantle sequence composed of peridotites and a crustal sequence composed of cumulate peridotites and gabbros that are intruded by diabases with some basalts. This article presents new whole-rock geochemical and geochronological data for peridotites, gabbros, diabases and basalts to revisit the petrogenesis and tectonic setting of the Yilashan mafic-ultramafic complex. Zircon laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) U-Pb ages of three diabase samples are 169.6 ± 3.3 Ma, 132.5 ± 2.5 Ma, and 133.6 ± 4.9 Ma, respectively. These ages together with previous studies indicate that the Yilashan mafic-ultramafic complex probably formed during the Jurassic-Early Cretaceous. The peridotites exhibit nearly U-shaped REE patterns and are distinct from abyssal peridotites. The diabase and basalt samples show arc features with selective enrichment in light rare earth elements (LREE) and large ion lithophile elements (LILEs; e.g. Rb, U, and Sr) and depletion in high field strength elements (HFSEs; e.g. Nb, Ta, and Ti). The gabbro samples display cumulate features with selective enrichment in LILEs (e.g. Rb, Ba, and Sr) but depletion in LREEs and HFSEs (e.g. Nb, Zr, and Ti). Combing the positive εNd(t) values (+6.1 to +10.0) and negative zircon εHf(t) values (-16.5 to -11.7 and -13.6 to -0.4) with older Hf model ages for the mafic rocks, these signatures suggest that the Yilashan mafic and ultramafic rocks likely originated from an ancient lithospheric mantle source with the addition of asthenospheric mantle materials and subducted fluids coupled with limited crustal contamination in a continental arc setting as a result of the southward subduction of the Bangong-Nujiang Tethys Ocean beneath the Lhasa terrane during the Jurassic-Early Cretaceous. [ABSTRACT FROM AUTHOR]

Mud volcanoes can provide important information about the underlying strata, hydrocarbon accumulation, and recent neotectonic movements in an area. The fluids erupting from mud volcanoes provide important information about their formation and evolution. The ion concentration and the hydrogen and oxygen isotopes of the fluids that were erupted from the three mud volcano groups, Baiyanggou, Aiqigou, and Dushanzi, and nearby rivers in the southern margin of the Junggar basin, northwestern China, are studied. The concentrations of Na and Cl in mud volcano fluids are clearly elevated, displayed as the Na-Cl type. The δD and δ18O values of the fluids are similar between the Baiyanggou and Dushanzi mud volcanoes, which are mainly from ancient sedimentary pore water. However, the Aiqigou mud volcano is depleted in dissolved Cl and shows lower δ18O values with mixed sources, including deep pore and local meteoric water. Two types of mud volcanoes are proposed in this study. One type is low-energy mud volcanoes with a low volume of fluid of deep origin on the hillcrest, which display as mud pool/pie/hole. The other type is high-energy mud volcanoes having mixed fluid origin in the valley and formed in the shape of a mud cone (dome). [ABSTRACT FROM AUTHOR]

The Baer ophiolitic massif is located in the northern sub-belt of the western segment of the Yarlung Zangbo Suture Zone (YZSZ) and mainly consists of a lherzolite-dominant mantle suite, dolerite intrusions and limited crustal outcrops. The dolerites show sub-ophitic texture and light rare earth element-depleted chondrite-normalized rare earth element patterns similar to normal-mid-ocean ridge basalts (N-MORB); though, they display enrichments in fluid-mobile elements (Rb, Ba, and Sr) and marked depletions in Th and Nb. The U–Pb ages of several magmatic zircon grains recovered from two dolerite samples indicate that the intrusion of the dikes into the Baer lherzolitic mantle occurred at 125.6–126.3 Ma, consistent with the widespread mafic magmatism between 120 and 130 Ma in the Yarlung Zangbo ophiolites. The dolerites have slightly more radiogenic87Sr/86Sr ratios (0.7043–0.7054) in comparison to N-MORB, whereas they show143Nd/144Nd values (0.513067–0.513114) similar to N-MORB and high zircon Hf-isotope compositions. They have a limited range of Nd-isotope (εNd(t) values: +8.2 to +9.1) and juvenile Hf-isotope compositions (εHf(t) values: +8.4 to +14.2 and +10.0 to +15.1) indicating derivation from mantle melts. The moderate spread in theεHf(t) values of zircons indicates derivation of the dolerites parental magma from a weakly contaminated spinel-bearing mantle source. This is also corroborated by the geochemical signatures of the Baer dolerites (enrichment in LILE and depletion in HFSE) suggesting minor slab input to the mantle source of the dike-filling melt. We suggest that the genesis of the dolerite dike-forming melt happened at a stage of subduction initiation in a sub-oceanic mantle domain mildly affected by fluids emanating from the downgoing slab. Our data combined with literature data allow us to presume that the intrusion of the dolerites into the Baer mantle corresponds to an early phase of subduction initiation beneath a developing forearc basin. [ABSTRACT FROM AUTHOR]

The eggs, larvae, nymphs and female adults of the carmine spider mite,Tetranychus cinnabarinus(Boisduval) were treated using corresponding sublethal dosages (LC10–LC50) of diflubenzuron. Then we examined the effect on the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione-S-transferases (GSTs), the total antioxidant capacity (T-AOC) and malondialdehyde (MDA) content. The results showed that the activities of SOD, CAT and POD at different developmental stages increased with increasing of diflubenzuron concentration, but when diflubenzuron concentration continued to increase, the activities decreased. GSTs activities, T-AOC and MDA content increased with the increasing of diflubenzuron concentration. The change trend of GSTs activities was as follows: eggs < larvae < nymphs < female adults. T-AOC in both nymphs and female mites was higher than that in eggs and larvae, and MDA contents in larvae, nymphs and female adults were always higher than that of eggs. The increasing of MDA concentration indicated that diflubenzuron stress led to lipid peroxidation in organisms. In summary, diflubenzuron stress resulted in oxidative stress and antioxidant enzymes played an important role in reducing oxidative damage in the carmine spider mite. [ABSTRACT FROM PUBLISHER]

The Lower Cretaceous lacks detailed comprehensive study of source rocks geochemistry characteristics and thermal evolution history as the target stratum of potential regional oil-gas exploration in the HaRi Sag, Yin-E Basin. Organic geochemistry methods were first applied to detailed study of organic matter content, type and maturity of Lower Cretaceous source rocks from the HaRi Sag. The results showed that the organic matter of K1Y formation Types I–II1with high content and Immature-Early mature, K1S formation kerogen Types II1–II2with relatively high content and Early-Mid Mature and K1B formation kerogen Types II2–III with low content and Late Mature-Main Gas Generation. The proposed maturity evolution history of source rocks in HaRi Sag based on EASYRO% model under the control of vitrinite reflectance (RO%) shows the maximum geothermal gradient reached 48–52°C/km and the maximum paleogeotemperature is over 190°C at the end of Early Cretaceous, and the main timing of hydrocarbon generation is 106.3–80.0 Ma. [ABSTRACT FROM AUTHOR]

The widespread mid-Cretaceous igneous rocks in the northern margin of the Lhasa Block play an important role in understanding deep geologic processes, matter exchange at depth, and tectonic evolution of the Tibetan Plateau. In this paper, we report new zircon U-Pb ages, whole-rock major and trace element data, and Sr-Nd-Pb-Hf isotope data from the Talabuco andesites and basalts, which were dated at ~111 Ma. These rocks belong to the high-K calc-alkaline and shoshonite series, and show enrichment in terms of large-ion-lithophile elements (LILEs, e.g. Rb, U, and Th) and light rare earth elements (LREEs), but depletion of high-field-strength elements (HFSEs, e.g. Nb and Ti). The (87Sr/86Sr)iratios of the Talabuco andesites range from 0.7043 to 0.7048, and theεNd(t) contents range from 0.68 to 4.33. The ratios of206Pb/204Pb,207Pb/204Pb, and208Pb/204Pb are 18.6064–18.8993, 15.6233–15.6707, and 38.8634–39.1720, respectively. The176Lu/177Hf and176Hf/177Hf ratios of one sample range from 0.00081 to 0.00206 and 0.28280 to 0.28296, respectively. TheεHf(t) values for this sample range from 3.4 to 9.1, and the two-stage model Hf age (TDM2) is 0.59–0.95 Ga. Combined with previous studies, the geochemical and isotopic data reveal that the parental magma of the Talabuco andesites was probably derived by partial melting of EM II-type sub-continental lithospheric mantle (SCLM). The Talabuco andesites are most likely generated by fractionation of mafic magma contaminated by subducted oceanic sediment and represent product of arc magmatism due to northward subduction of the Yarlung Zangbo Neo-Tethyan slab or southward subduction of the Bangong Meso-Tethyan slab. [ABSTRACT FROM AUTHOR]

Serpentinites from Junan (JN), Rizhao (RZ), and Rongcheng (RC) in the Sulu ultra-high-pressure (UHP) terrane, China, were analysed for U–Pb zircon geochronology, mineral chemistry, whole-rock major and trace element chemistry (including rare-earth elements (REEs) and platinum-group elements (PGEs)), and Re–Os isotopes, in order to better constrain their petrogenesis and geodynamic process. The serpentinite zircons yield two age groups: 731 ± 10 to 780 ± 10 Ma for relic magmatic zircon cores, which may indicate early crystallization and emplacement of the peridotite in the Yangtze crust, and 209 ± 2 to 218 ± 3 Ma for metamorphic zircon, which coincides with Triassic UHP metamorphism. The spinels in the serpentinites exhibit significant Cr# variation (0.6–0.91) and have undergone multi-stage metamorphism. The serpentinites are characterized by enrichment in incompatible trace elements, low Ni and IPGE concentrations, and high Pd/Ir ratios, and the bulk-rock major elements plot in the ultramafic cumulate region. Their Re and Os concentrations are similar to those of typical orogenic peridotite, but they have high187Os/188Os ratios (0.12433–0.14423). We believe that the serpentinite’s protolith consisted of cumulates from an asthenosphere-derived melt that intruded into the continental crust of the Yangtze craton in the Neoproterozoic. These cumulates were later subducted and metamorphosed during the subduction of the Yangtze craton in the Triassic. The serpentinites underwent melt–rock interactions and fluid enrichment, both prior to and during serpentinization. [ABSTRACT FROM PUBLISHER]

Although numerous ages have been obtained for the Chinese southwestern Tianshan high pressure/ultrahigh pressure-low temperature (HP/UHP-LT) metamorphic belt in the past two decades, its exhumation history is still controversial. The poor age constraint was related to the appealing low metamorphic temperatures and excess Ar commonly present under HP/UHP conditions. This study aims to provide new age constraints on the orogen’s exhumation by obtaining40Ar/39Ar mica ages using the conventional step-heating technique, with emphasis on the avoidance of excess Ar contamination. From a cross section along the Kekesu Valley, four samples, three from the HP-LT metamorphic belt (TK050, TK051, and TK081) and one from the southern margin of the low pressure metamorphic belt (TK097), were selected for40Ar/39Ar dating. Phengites from garnet glaucophane schist TK050 and the surrounding rock garnet phengite schist TK051 yield comparable plateau ages of 321.4 ± 1.6 and 318.6 ± 1.6 Ma, respectively, while epidote mica schist TK081 gives a younger plateau age of 293.3 ± 1.5 Ma. Considering the chemical compositions of phengites, mineral assemblages, and microstructures in the thin slices, we suppose that the former represents the time the HP rocks retrograded from the peak stage (eclogite facies) to the (epidote)-blueschist facies, whereas the latter reflects greenschist facies overprinting. Biotite and muscovite from two-mica quartzite TK097 give similar plateau ages of 253.0 ± 1.3 and 247.1 ± 1.2 Ma, interpreted to date movement on the post collisional transcrustal South Nalati ductile shear zone. By combining our new ages with published data, a two-stage exhumation model is suggested for the Chinese southwestern Tianshan HP/UHP-LT metamorphic belt: initial fast exhumation to a depth of about 30–35 km by ~320 Ma was followed by relatively slow (~1 mm year–1) uplift to ~10 km by ~293 Ma. [ABSTRACT FROM AUTHOR]

New zircon U–Pb age data, whole-rock major and trace elemental data, and Sr–Nd–Pb isotopic data of granitoids from the Woruo and Bailong areas in the southern margin of the Qiangtang Block (western Tibet, China) provide important evidence for northward subduction of the Bangong Meso-Tethyan oceanic lithosphere. Five granitoid samples are dated at 120.7–112.7 Ma. These granitoids mostly belong to calc-alkaline and high-K calc-alkaline series, and show strong enrichments in large-ion lithophile elements (e.g. Rb, Ba, and Th), depletions in Nb and Ta, and negative correlations between P2O5, TiO2, MgO, and SiO2 contents, consistent with the evolution trend of I-type magmas. The samples are characterized by a wide range of Sr–Nd–Pb isotopic compositions (initial εNd values from −0.06 to 5.84, initial 87Sr/86Sr from 0.704458 to 0.705596, (206Pb/204Pb)0 from 18.5436 to 19.2465, (207Pb/204Pb)0 from 15.6115 to 15.6712, and (208Pb/204Pb)0 from 38.6427 to 39.6942). The trace elemental and Sr–Nd–Pb isotopic data suggest that these samples are derived from a mixture of lower crust and mantle materials. Together with the published data, these Early Cretaceous magmatic rocks represent a continental arc setting formed by the northward subduction of the Bangong Meso-Tethys during the Early Cretaceous (120–112 Ma). [ABSTRACT FROM AUTHOR]

La modified Pb(Mg1/3Nb2/3)O3-PbTiO3(PLMNT) transparent electro-optic (EO) ceramics with pure perovskite phase were fabricated by the uniaxial hot-press sintering method. An improved hot-press sintering technique with varied atmosphere was proposed to eliminate the pore defects. It consists of four stages: 1) sintering at a relatively low temperature (800°C) in the vacuum atmosphere first, and then in the pure O2atmosphere; 2) sintering in a pure O2atmosphere at high temperature by uniaxial hot-press method; 3) replacing the O2atmosphere with CO2gas to eliminate the residual closed pores; 4) finally exchanging CO2atmosphere with pure O2gas to eliminate the oxygen vacancies. The research results certified that the thermal treatment in the vacuum atmosphere and CO2atmosphere could eliminate the residual closed pores and improve the transmittance of the PLMNT transparent ceramics effectively. By the improved hot-press sintering technique, the optical transmittance of the polished PLMNT transparent ceramics with a thickness of 0.35mm increases from 61% to 64% at 632.8nm. The reasonable explanation was given about the mechanism of the improvements of this sintering technique. [ABSTRACT FROM AUTHOR]

Lithium zinc (Li0.35+xZn0.3Mn0.08Fe2.27O4±δ) ferrites with excess lithium concentrationxvarying from 0 to 0.08 in steps of 0.02 were prepared by conventional oxide ceramic method. XRD patterns confirm the spinel structure of Li0.35+xZn0.3Mn0.08Fe2.27O4±δferrites. According to the results of SEM photograph, excess lithium can compensate the volatilization of lithium during the sintering process and an appropriate amount of excess lithium is found to decrease the material porosity obviously, which improves the comprehensive performance of Li-Zn ferrites effectively. As the excess lithium concentration increases, the grain growth is restricted and the average grain size decreases. The bulk densitydand saturation magnetizationMsincrease firstly and then decrease with the increase of Li-excessx. In the meanwhile, the coercive forceHcshows a gradually increasing trend from 190A/m to 1036A/m, and the resistivity ρ has a monotonically increase due to the decrease of Fe2+irons. [ABSTRACT FROM AUTHOR]

The nature of the Namco–Renco ophiolites in the northern Lhasa subterrane is widely disputed. To investigate their formation age, petrogenesis, and tectonic setting, the harzburgites, basalts, and metagabbros of the Namco ophiolite and the harzburgites, lherzolites, gabbros, and diabasic dikes of the Renco ophiolite were selected for whole-rock geochemical and zircon U-Pb dating andin situLu-Hf isotopic analyses. The geochemical and geochronological data indicate that the Namco metagabbros were generated at 178.0 ± 2.9 Ma, along with the Namco–Renco peridotites formed in the initial stage of a continental margin basin; whereas the Renco gabbros were developed at 149.7 ± 1.6 Ma, along with the Renco diabasic dikes and Namco basalts formed later in a mature back-arc basin. The Namco–Renco ophiolites were derived from a depleted mantle source with involvement of minor older crustal materials. Combined with the regional geological background, the Namco–Renco ophiolites were likely formed mainly associated with the southward subduction of the Bangong–Nujiang oceanic lithosphere beneath the Lhasa terrane. This study provides new constraints on the formation ages of the Namco–Renco ophiolites and the tectonic evolution of the Namco–Renco Ocean. [ABSTRACT FROM AUTHOR]

In this paper, a new quad-band Wilkinson power divider (WPD) is proposed and designed with an analytical method. A quad-band impedance transformer built up by three transmission lines and two loaded shorted-stubs is firstly proposed. The related design equations are deduced by matrix transformation. With proper assumption, a simple analytical design method is presented for the quad-band WPD, and the derived equations and plotted curves can be used for the design. The designed quad-band WPD is an equal power division structure and only one surface-mounted resistor is needed. It has been demonstrated that our proposed WPD possesses simple configuration, small size, low cost, and good performance, i.e. high isolation, low insertion, and return losses, for the quad bands simultaneously from the simulated and measured results. [ABSTRACT FROM AUTHOR]

Subduction of the Bangong Meso-Tethys and collision between the Lhasa and Qiangtang blocks were important for the growth of Tibetan crust, as well as the development of super-large porphyry copper deposits in central Tibet. However, the initiation and closure timing, and nature and structure of the Bangong Meso-Tethys are still poorly constrained. Petrology, geochronology, and geochemistry of the Rebang Co and Julu ophiolites in the western part of the suture zone are used to constrain the tectonic history and structure of the Bangong Meso-Tethys. These two suites consist of ultramafic rocks, gabbro and diabase dikes, pillow basalts, and radiolarian cherts. Zircon U–Pb dating of zircon grains of gabbros yields well-defined weighted mean ages of 161.5 ± 1.5 Ma and 103.8 ± 3.9 Ma for the Rebang Co and Julu suites, respectively. Both of ophiolitic suites have mid-oceanic ridge basalt and island-arc tholeiite affinities, similar to back-arc basin crust. We suggest these suites formed above an intra-oceanic subduction zone at least during Middle Jurassic through mid-Cretaceous times. Along with coeval subduction beneath the southern Qiangtang margin, as well as fore-arc basin development, the Bangong Meso-Tethys has a complicated structure and history. Clearly, subduction in the Bangong Meso-Tethys was still active during mid-Cretaceous time and the Meso-Tethys did not close until Late Cretaceous time. [ABSTRACT FROM AUTHOR]

For the first time, N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC) was prepared through a fast, easy and efficient method with the assistance of microwave irradiation, and the quaternized chitosan was also degraded via the microwave irradiation. A comparative study was performed by using the conventional heating method to prepare HTCC. The structure and property of the quaternized chitosan obtained by these two methods were characterized by GPC, XRD, FTIR, NMR, TG and elemental analysis. It was shown that quaternized chitosan was successfully prepared within 50 min via microwave irradiation method, while a much longer time of 6-7 h was needed with the conventional heating method. The substitutions both occurred on the C2 position of chitosan with the two different methods, and their HTCC products had weight average similar molecular weight (Mw), structure and thermal stability. The HTCC prepared by the microwave irradiation method had a little lower degree of substitution (DS) than those prepared via conventional heating with the same mole ratio (6:1) of the intermediate to chitosan. The degradation study showed that the Mw of HTCC decreased rapidly from 4.6 × 105 to 1.1 × 105 in 1 h under microwave irradiation, while it only decreased from 4.6 × 105 to 2.1 × 105in 1 h through conventional heating degradation. These results revealed that microwave irradiation is a more efficient and environment-friendly way to obtain the water-soluble chitosan derivatives and their degraded products. [ABSTRACT FROM AUTHOR]

Titania (TiO 2 ) nanoparticles with primary diameters of less than 30 nm were produced by the thermal decomposition of TTIP and by the oxidation of TiCl 4 in a cylindrical furnace reactor at 1200°C. Particle size, crystalline phase, and phase transformation were investigated as a function of precursor concentration and total flow rate by TEM, a DMA/CNC system, XRD, and TG-DTA. The results show that both particle size and number concentration were increased with increasing precursor concentration, and that the primary size could be controlled by changing the operating conditions. An anatase-to-rutile phase transformation occurred at TTIP concentrations above 7.68×10 -6 mol/l and this was enhanced with increasing precursor concentration. It is noteworthy that the transformation is independent of grain size but appears to be related to the presence of carbon impurities in the nanoparticles. [ABSTRACT FROM AUTHOR]

As a new dewatering technology with high efficiency and energy saving, electro-osmotic dewatering can be applied to food processing. The objective of this work was to study the effect of combined field dewatering (CFD) involving electro-osmosis and mechanical pressure on the quality of tofu sheet. Combined field dewatering was performed on the dewatering process of tofu sheet for 10 to 30min at a voltage ranging from 30 to 50V under various pulse-time ratio (t[SUB+] 120 s, t[SUB-] = 5 s) electric field and 0.047 MPa pressure field. The texture and structure of tofu sheet after treatments were examined by a rheometer and scanning electron microscope (SEM). The result showed that the three quality indexes, i.e., hardness, tensile strength, and ductility of tofu sheet near the anode were 45%, 30%, and 12% higher respectively than those dewatered by common mechanical pressure method. However, those near the cathode were 15%, 25%, and 10% lower respectively. When the electric field was applied for 10min at 30V, these indexes reached their maximum values. Meanwhile, the tofu sheet structure near the anode was more compact and homogeneous than that near the cathode. The result indicated that CFD could enhance the quality of tofu sheet. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome ofEuthrix laeta(GenBank accession number KU870700) was sequenced by traditional PCR amplification and primer walking methods. The total length was 15,368 bp, including 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and a A + T-rich region. The base composition of the genome was A (40.85%), T (39.34%), C (12.01%) and G (7.8%), respectively. The arrangement of all genes was identical to other lepidopteran insects. The phylogenetic relationships were established based on the nucleotide sequences of 13 protein-coding genes of mitochondrial genomes by the neighbor-joining method. The molecular-based phylogeny supported the traditional morphological classification on relationships within Lepidoptera species. [ABSTRACT FROM PUBLISHER]

In this study, the complete mitochondrial genome ofCryptolestes pusillus(GenBank accession number KT070713) was sequenced by long PCR and primer walking methods. The total length of mitochondrial DNA is 15 502 bp and contains 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a A + T-rich region. The base composition of the genome is A (39.04%), T (37.07%), C (23.4%), and G (14.6%). Except forCOIandATP8with TCC and ATC as start codon, respectively, the remaining protein-coding genes initiated with the three orthodox start codons. Two complete stop codons (TAA and TAG) and two incomplete stop codons (COIIIstop with T andND5stop with TA) were used in the protein-coding genes. The A + T-rich region is located between12s rRNAandtRNAIlewith the length of 859 bp. The phylogenetic relationships of Coleoptera species were constructed based on the nucleotide sequences of 13 protein-coding genes of mitogenome using the neighbor-joining method. The molecular-based phylogenetic analysis supported the traditional morphological classification on relationships within Coleoptera species. [ABSTRACT FROM AUTHOR]

We presented the complete mitogenome ofCryptolestes turcicus(GenBank accession number KT070712) in this study. The total length of mitochondrial DNA is 15 517 bp and contains 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a control region. The overall base composition of the genome is A (39.48%), T (37.38%), C (13.97%), and G (9.16%) with an A + T-rich hallmark. The start codon was ATN in all the mitochondrial protein-coding genes, such asND2, COI, ATP6, ND5, ND4LandND1start with ATA,COII, ATP8, ND3,andND6genes employing ATT, while the rest using ATG as a start codon. The stop codon was mainly TAA or TAG in most of the mitochondrial protein-coding genes, wherever T(A) was found inCOII, COIII, ND4, andND4Lgenes. The A + T-rich region is located between12S rRNAandtRNAIlewith a length of 857 bp. [ABSTRACT FROM AUTHOR]

We determined the complete mitochondrial genome (mitogenome) sequence ofCryptolestes ferrugineus(GenBank accession number KT182067) by the long PCR and primer walking method. The mitochondrial genome is a typical circular DNA molecule of 15 511 bp in length, and contains 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a A + T-rich region (D-loop). The order of 37 genes was typical of insect mitochondrial DNA sequences described to date. The base composition of the genome is A (39.17%), T (37.24%), C (14.22%), and G (9.37%) with an A + T-rich hallmark as that of other invertebrate mitochondrial genomes. All protein-coding genes start with ATN codon and terminate with the stop codon T (AA) or TAG. The A + T-rich region is located between 12S rRNA andtRNAIle. In this study, the phylogenetic relationships of Coleoptera species were constructed based on the nucleotides sequences of 13 PCGs of mitogenomes. The molecular-based phylogeny supported the traditional morphological classification on relationships within Coleoptera species. [ABSTRACT FROM AUTHOR]

In this study, the first complete mitochondrial genome (mitogenome) sequence ofCacopsylla coccinaewas determined by long PCR and primer walking methods. The complete mitochondrial genome is 14,832 bp in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes as well as a control region. The overall base composition of the genome is A (38.16%), T (33.88%), C (17.95%) and G (10.01%). Stop codon was incomplete forcoxIIgene andND1gene. The gene overlaps were suggested between 13 pairs of the contiguous genes inC. coccinae.The mitogenome would contribute to resolving phylogenetic position and interrelationships ofCacopsylla. [ABSTRACT FROM AUTHOR]

We present the complete mitogenome ofCethosia biblis(Drury) (Lepidoptera: Nymphalidae) in this article. The mitogenome was a circle molecular consisting of 15,286 nucleotides, 37 genes, and an A + T-rich region. The order of 37 genes was typical of insect mitochondrial DNA sequences described to date. The overall base composition of the genome is A (37.41%), T (42.80%), C (11.87%), and G (7.91%) with an A + T-rich hallmark as that of other invertebrate mitochondrial genomes. The start codon was mainly ATA in most of the mitochondrial protein-coding genes such asND2, COI, ATP8, ND3, ND5, ND4, ND6,andND1, butCOII, ATP6, COIII, ND4L,andCobgenes employing ATG. The stop codon was TAA in all the protein-coding genes. The A + T region is located between12S rRNAandtRNAMet. The phylogenetic relationships of Lepidoptera species were constructed based on the nucleotides sequences of 13 PCGs of mitogenomes using the neighbor-joining method. The molecular-based phylogeny supported the traditional morphological classification on relationships within Lepidoptera species. [ABSTRACT FROM AUTHOR]

We determined the complete mitochondrial genome (mitogenome) sequence ofPapilio demoleus(GenBank accession number KR024009) by long PCR and primer walking methods. The total length of mitochondrial DNA is 15,249 bp containing 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and a control region. The overall base composition of the genome is A (39.31%), T (41.57%), C (11.33%) and G (7.78%) with an A + T-rich region, similar to other invertebrate mitochondrial genomes. The start codon was mainly ATG in most of the mitochondrial protein-coding genes such asCOII, ATP6, COIII, ND4, ND4L, CobandND1, while ATA forND2, COI, ATP8, ND3, ND5andND6genes. The stop codon was mainly TAA in most of the mitochondrial protein-coding genes, whereas TAG was found inND1gene only. The A + T region is located between12S rRNAandtRNAMetwith a length of 403 bp. [ABSTRACT FROM AUTHOR]

In this study, the complete mitochondrial genome (mitogenome) sequence ofEuseius nicholsi(Acarinae: Phytoseiidae) was determined by long PCR and primer walking methods. The complete mitochondrial genome is 15,561 bp in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 21 transfer RNA genes. The overall base composition of the genome is A (34.69%), T (43.14%), C (8.06%) and G (14.10%). Stop codon was missed for theCOXIIIgene inE.nicholsi.The mitogenome would contribute to resolving phylogenetic position and interrelationships ofEuseius. [ABSTRACT FROM PUBLISHER]

The whole sequence (15,057 bp) of the mitochondrial DNA (mtDNA) of the terrestrial snailAchatina fulica(order Stylommatophora) was determined. The mitogenome, as the typical metazoan mtDNA, contains 13 protein-coding genes (PCG), 2 ribosomal RNA genes (rRNA) and 22 transfer RNA genes (tRNA). The tRNA genes include twotrnSwithout standard secondary structure.Interestingly, among the known mitogenomes of Pulmonata species, we firstly characterized an unassigned lengthy sequence (551 bp) between the cox1 and thetrnVwhich may be the CR for the sake of its AT bases usage bias (65.70%) and potential hairpin structure. [ABSTRACT FROM AUTHOR]

AlthoughNapialus hunanensisis important as the host ofCordyceps hawkesii(a valuable medicine in China), it remains poorly known especially on molecular level. To get a better understanding of it, the complete mitogenome was sequenced and annotated. It was 15,301 bp in length, contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and an AT rich region. The base composition was 40.68% for A, 41.17% for T, 7.56% for G and 10.59% for C on the heavy strand. Except theCOIwith CGA andND1with TTG, the remaining protein-coding genes started with typical ATN. These coding genes ended up with TAA as well as an incomplete stop codon T (COIIandND3). According to other Hepialidae species, the rearrangement of tRNAMetinN. hunanensisis the ancestral type. The mitochondrial genome ofN. hunanensisis an important source for species identification and phylogenetic analyses. [ABSTRACT FROM AUTHOR]

In this study, the first complete mitochondrial genome (mitogenome) of the mold mite,Tyrophagus putrescentiaewas determined by long PCR and primer walking methods. The mitogenome was 13,288 bp in length, including 13 typical invertebrate protein-coding genes, 18 transfer RNA genes and 2 ribosomal RNA genes. The overall base composition of the heavy strand is 22.5% A, 48.2% T, 13.2% C and 16.1% G, with a A+T bias. Stop codon was incomplete for ND4 gene and ND2. Gene overlaps were observed between 12 pairs of the contiguous genes inT. putrescentiae.The study also displayed that four tRNAs were missed forT. putrescentiae. Researches on mitogenome would further contribute to resolving phylogenetic position and interrelationships ofTyrophagus. [ABSTRACT FROM AUTHOR]

In this study, the complete mitochondrial genome (mitogenome) sequence ofAleuroglyphus ovatus(Acarinae:Aleuroglyphus) was determined by long PCR and primer walking methods. The complete mitochondrial genome is 14,305 bp in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes as well as a displacement loop (D-loop). The overall base composition of the genome is A (23.61%), T (44.60%), C (13.03%) and G (18.76%) respectively. Stop codon was missed for the CYTB gene and the gene overlaps were suggested between ten pairs of the contiguous genes inA. ovatus.The mitogenome would contribute to resolving phylogenetic position and interrelationships ofAleuroglyphus. [ABSTRACT FROM AUTHOR]

To know the genetic structure and phylogeny status, the complete mitochondrial genome ofThitarodes puiwas the first time to be sequenced. The genome was 15,064 bp in length and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, as well as an AT rich region. The base composition of the genome was A (40.93%), T (39.80%), C (11.72%) and G (7.55%), with an AT content of 80.73%. It is interesting to that the COI would start with CGA. The tRNA order between ND2 and AT rich region was tRNAIle–tRNAGln–tRNAMet, which confirms the thesis thatThitarodeshas the ancestral gene arrangement. It is surprised that AT-rich region was 287 bp in length and became the shortest in contrast to other insects of Hepialidae. [ABSTRACT FROM AUTHOR]