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Conceptually mimicking biomolecules' ability to construct multiple‐helical aggregates with emergent properties and functions remains a long‐standing challenge. Here we report an atom‐precise 18‐copper nanocluster (NC), Cu18H(PET)14(TPP)6(NCS)3 (Cu18H) which contains a pseudo D3‐symmetrical triple‐helical Cu15 core. Structurally, Cu18H may be also viewed as sandwich type of sulfur‐bridged chiral copper cluster units [Cu6−Cu6−Cu6], endowing three‐layered 3D chirality. More importantly, the chiral NCs are aggregated into an infinite double‐stranded helix supported by intra‐strand homonuclear C−H⋅⋅⋅H−C dihydrogen contacts and inter‐strand C−H/π and C−H/S interactions. The unique multi‐layered 3D chirality and the double‐helical assembly of Cu18H are evocative of DNA. Moreover, the collective behaviours of the aggregated NCs not only exhibit crystallization‐induced emission enhancement (CIEE) and aggregation‐induced emission enhancement (AIEE) effects in the deep‐red region, but also efficiently catalyze electron transfer (ET) reaction. This study thus presents that hierarchical assemblies of atomically defined copper NCs could be intricate as observed for important biomolecules like DNA with emergent properties arising from aggregated behaviours. [ABSTRACT FROM AUTHOR]

Conceptually mimicking biomolecules' ability to construct multiple‐helical aggregates with emergent properties and functions remains a long‐standing challenge. Here we report an atom‐precise 18‐copper nanocluster (NC), Cu18H(PET)14(TPP)6(NCS)3 (Cu18H) which contains a pseudo D3‐symmetrical triple‐helical Cu15 core. Structurally, Cu18H may be also viewed as sandwich type of sulfur‐bridged chiral copper cluster units [Cu6−Cu6−Cu6], endowing three‐layered 3D chirality. More importantly, the chiral NCs are aggregated into an infinite double‐stranded helix supported by intra‐strand homonuclear C−H⋅⋅⋅H−C dihydrogen contacts and inter‐strand C−H/π and C−H/S interactions. The unique multi‐layered 3D chirality and the double‐helical assembly of Cu18H are evocative of DNA. Moreover, the collective behaviours of the aggregated NCs not only exhibit crystallization‐induced emission enhancement (CIEE) and aggregation‐induced emission enhancement (AIEE) effects in the deep‐red region, but also efficiently catalyze electron transfer (ET) reaction. This study thus presents that hierarchical assemblies of atomically defined copper NCs could be intricate as observed for important biomolecules like DNA with emergent properties arising from aggregated behaviours. [ABSTRACT FROM AUTHOR]

Conceptually mimicking biomolecules’ ability to construct multiple‐helical aggregates with emergent properties and functions remains a long‐standing challenge. Here we report an atom‐precise 18‐copper nanocluster (NC), Cu18H(PET)14(TPP)6(NCS)3 (Cu18H) which contains a pseudo D3‐symmetrical triple‐helical Cu15 core. Structurally, Cu18H may be also viewed as sandwich type of sulfur‐bridged chiral copper cluster units [Cu6−Cu6−Cu6], endowing three‐layered 3D chirality. More importantly, the chiral NCs are aggregated into an infinite double‐stranded helix supported by intra‐strand homonuclear C−H⋅⋅⋅H−C dihydrogen contacts and inter‐strand C−H/π and C−H/S interactions. The unique multi‐layered 3D chirality and the double‐helical assembly of Cu18H are evocative of DNA. Moreover, the collective behaviours of the aggregated NCs not only exhibit crystallization‐induced emission enhancement (CIEE) and aggregation‐induced emission enhancement (AIEE) effects in the deep‐red region, but also efficiently catalyze electron transfer (ET) reaction. This study thus presents that hierarchical assemblies of atomically defined copper NCs could be intricate as observed for important biomolecules like DNA with emergent properties arising from aggregated behaviours. [ABSTRACT FROM AUTHOR]

• This study proposes a multi wavelength optical image feature fusion method for improving the effectiveness of subdural hematoma image reconstruction. • CT images of real patients was used in this study to establish a 3D three-layer tissue brain tissue model. • The average VRE and average AMD of hematoma reconstruction in the model which is using this method are only 0.66 % and 0.0052 mm−1. • Compared with the model which is directly using optical information as input, the method make the average VRE and average AMD of hematoma reconstruction respectively decreased by 80.0% and 27.8%. Diffuse optical tomography (DOT) under medical image guidance can be used to reconstruct images of subdural hematomas for monitoring purposes. However, when the shape of hematoma is irregular or the signal to noise ratio(SNR) of input signal is low, the accuracy and robustness of this method both decrease. In order to alleviate this situation and improve the reconstruction effect of cerebral hematoma images, a multi wavelength optical image feature fusion method was proposed in this paper. Experimental results show that the mean relative volume error (VRE) of the hematoma reconstruction model based on the multi-wavelength optical image feature fusion method is only 0.66 %, and the mean value of the average Manhattan distance (AMD) between the reconstructed absorption coefficient and the true absorption coefficient is 0.0052 mm−1. Compared with the model using single-wavelength optical image mapping feature extraction method, the multi-wavelength optical image feature fusion method reduces the average VRE of the model by 16.5 %, and the average AMD by 16.1 %. And compared with the model directly inputting single-wavelength optical information, its average VRE and average AMD decreased by 80.0 % and 27.8 %. This method has clinical application significance for the monitoring of subdural hematomas. [ABSTRACT FROM AUTHOR]

Interactions of dendrimers on solid substrates are important in processes involving their coating, flocculation, sedimentation, etc. The adsorption of positively charged poly(amidoamine) dendrimers on hematite/water interface has been investigated in this work as a function of pH, ionic strength, and dendrimer generation by measuring the amount of dendrimers adsorbed and zeta potential changes upon adsorption. Two generations of dendrimers, G3 and G7, were selected, representing “earlier” and “later” generations. At pH 9, the adsorption density of G3 dendrimer on negatively charged hematite increased and reached a plateau with an increase in dendrimer concentration. At pH 4, there is no measurable adsorption of the dendrimer on positively charged hematite in 0.01 M NaCl solutions, and a “negative adsorption” in the distilled water, a condition of a much lower ionic strength showing that the interaction between the hematite surface and the dendrimers is governed mainly by the electrostatic forces. At pH 9, adsorption of G7 dendrimer on hematite is much higher than that of G3 dendrimer and it did not even reach a plateau in the tested dendrimer concentration range, a result consistent with the hypothesis that the adsorbed G7 dendrimers assume a compressed conformation while adsorbed G3 dendrimer molecules take more expanded conformation on the solid. With the increase in the adsorption of G3 dendrimer at pH 9, zeta potential of hematite changed from negative to positive and stayed constant when the adsorption reached a plateau. Clearly, deposition of dendrimers can be controlled by manipulating the interfaces and charge of the solid adsorbent such as hematite. [Copyright &y& Elsevier]

Diet plays a crucial role in shaping the gut microbiota and overall health of animals. Traditionally, silkworms are fed fresh mulberry leaves, and artificial diets do not support good health. The aim of this study was to explore the relationship between the dietary transition from artificial diets to mulberry leaves and the effects on the gut microbiota and physiological changes in silkworms as a model organism. With the transition from artificial diets to mulberry leaves, the diversity of the silkworm gut microbiota increased, and the proportion of Enterococcus and Weissella, the dominant gut bacterial species in silkworms reared on artificial diets, decreased, whereas the abundance of Achromobacter and Rhodococcus increased. Dietary transition at different times, including the third or fifth instar larval stages, resulted in significant differences in the growth and development, immune resistance, and silk production capacity of silkworms. These changes might have been associated with the rapid adaptation of the intestinal microbiota of silkworms to dietary transition. This study preliminarily established a dietary transition–gut microbial model in silkworms based on the conversion from artificial diets to mulberry leaves, thus providing an important reference for future studies on the mechanisms through which habitual dietary changes affect host physiology through the gut microbiome. [ABSTRACT FROM AUTHOR]

Under the assistance of the state‐of‐the‐art meta‐dynamics simulations, in this contribution, we report a push‐pull‐type acylhydrazone 4(Z) ([Z)‐2‐(naphthalen‐2‐yloxy)‐N'‐(pyridine‐2‐ylmethylene)acetohydrazide] connecting an electron‐donating naphthalene ether group with an accepting pyridyl unit, which could be thermally converted to its configurational isomer 4(E) ([E)‐2‐(naphthalen‐2‐yloxy)‐N'‐(pyridine‐2‐ylmethylene)acetohydrazide]. The thermally triggered Z‐to‐E configurational isomerization not only involves up to five chemical bonds undergoing 180° rotation in the backbone of acylhydrazone, but changes the crystal packing symmetry from a centrosymmetric space group to a non‐centrosymmetric one. Most impressively, the acentric crystal arrangement of 4(E) exhibits a second‐harmonic generation (SHG) active response, about 2.5 times than that of KH2PO4 (KDP) standard. [ABSTRACT FROM AUTHOR]

Simple Summary: Silkworms have remarkable protein synthesis ability, which is favored by biomaterials and biomedicine researchers. The silk gland is the most concerned target tissue of sericulture. Many studies have focused on introducing exogenous functional fibrin genes into the silkworm genome, and have obtained biomedical proteins with good biological activity and multifunctional silk fibers with special properties using the silk gland bioreactor. However, the silk gland of transgenic silkworms often suffers from low vitality, stunting and other problems, and the reasons are still unknown; the biosafety of transgenic silkworms is also unknown. Therefore, we studied the effect of the recombinant Ser3 ectopic gene expressed in the posterior silk gland on hemolymph melanization and metabolism in silkworms. The results showed that although the mutant had normal vitality in normal environments, hemolymph metabolism and immunity were significantly affected. Therefore, the results have positive significance to promote the safe assessment and development of genetically modified organisms. The transgenesis of silkworms is an important way to innovate genetic resources and silk function. However, the silk-gland (SG) of transgenic silkworms, which is the most concerned target tissue of sericulture, often suffers from low vitality, stunting and other problems, and the reasons are still unknown. This study trans engineered recombinant Ser3, a middle silk gland (MSG) specific expression gene, in the posterior silk gland (PSG) of the silkworm, and studied hemolymph immune melanization response changes in mutant pure line SER (Ser3+/+). The results showed that although the mutant had normal vitality, the melanin content and phenoloxidase (PO) activity in hemolymph related to humoral immunity were significantly reduced, and caused significantly slower blood melanization and weaker sterilization ability. The mechanism investigation showed that the mRNA levels and enzymatic activities of phenylalanine hydroxylase (PAH), tyrosine hydroxylase (TH) and dopamine decarboxylase (DDC) in the melanin synthesis pathway in mutant hemolymph, as well as the transcription levels of the PPAE, SP21 and serpins genes in the serine protease cascade were significantly affected. Moreover, the total antioxidant capacity, superoxide anion inhibition capacity and catalase (CAT) level related to the redox metabolic capacity of hemolymph were significantly increased, while the activities of superoxide dismutase (SOD) and glutathione reductase (GR), as well as the levels of hydrogen peroxide (H2O2) and glutathione (GSH), were significantly decreased. In conclusion, the anabolism of melanin in the hemolymph of PSG transgenic silkworm SER was inhibited, while the basic response level of oxidative stress was increased, and the hemolymph immune melanization response was decreased. The results will significantly improve the safe assessment and development of genetically modified organisms. [ABSTRACT FROM AUTHOR]

The female Bombyx mori accumulates a large amount of egg proteins, mainly Vg and 30K, during egg formation to provide nutrition for embryo development. The synthesis and transport of Vg have been extensively studied, particularly the regulation of Vg transcription induced by 20E; however, the mechanism of 30K protein synthesis is poorly studied. As a model organism of the order Lepidoptera, B. mori has high reproduction potential. In the present study, we found that the FHL2 homologous gene (BmFhl2) in B. mori is involved in inhibiting female egg formation by influencing the synthesis of 30K protein. Interference of BmFhl2 expression in silkworm females increased 30K protein synthesis, accelerated ovarian development, and significantly increased the number of eggs produced and laid; however, the 20E pathway was inhibited. The transcription levels of Vg and 30Kc19 were significantly downregulated following BmFhl2 overexpression in the silkworm ovarian cell line BmN. The Co-IP assay showed that the potential binding protein of BmFHL2 included three types of 30K proteins (30Kc12, 30Kc19, and 30Kc21). These results indicate that BmFHL2 participates in egg formation by affecting 30K protein in female B. mori. [ABSTRACT FROM AUTHOR]

The method of magnetic resonance imaging (MRI) guided diffuse optical tomography (DOT) can achieve accurate monitoring of subdural hematomas. However, the accuracy, robustness and the noise immunity of this method decreased when the hematoma is irregular. To optimize the prediction effect of hematoma expansion and the robustness and the noise immunity of model in clinical application, a multidimensional data amplification method for individual hematoma training data sets using boundary extraction and shrinking algorithms and multiple orders of magnitude noise data was proposed in this study. The experimental results show that the average error of reconstructed hematoma volume based on the SAE network model using Spatial dimension data amplification method was 0.51 ml, the relative volume error(VRE) of it was only 1.07 %. On this basis, SNR dimension data amplification method reduced the average reconstruction volume error of the model by 82 %. Thus, the proposed improvement of the training set data method based on an individual's own MRI data can effectively enhance the continuous monitoring accuracy of a cerebral hematoma under the DOT method, which would have great significance in clinical application. [ABSTRACT FROM AUTHOR]

Temperature is an important environmental factor affecting the growth and development of silkworm (Bombyx mori). To analyze the effect of intestinal microbes on silkworm in response to a high-temperature environment, this study used a combination of high throughput sequencing and biochemical assays to detect silkworm intestinal microbes treated with high temperature for 72 h. The results show that high temperature affects the intestinal microbes of silkworm and that there are sex differences, specifically, females were more sensitive. The changes in the metabolism and transport ability of silkworm intestinal tissues under high temperature are related to the intestinal microbes. High temperatures may affect the intestinal microbes of silkworms, regulating the activity of related digestive enzymes and substance transport in the intestine, thereby affecting the silkworm's digestion and absorption of nutrients, and ultimately affecting growth and development. [ABSTRACT FROM AUTHOR]

Host–pathogen interactions are complex processes and it is a central challenge to reveal these interactions. Fungal infection of silkworm, Bombyx mori, may induce a variety of responsive reaction. However, little is known about the molecular mechanism of silkworm immune response against the fungal infection. To obtain an overview of the interaction between silkworm and an entomopathogenic fungus Beauveria bassiana, Digital Gene Expression profiling, a tag based high-throughput transcriptome sequencing method, was employed to screen and identify differentially expressed genes (DEGs, FDR≤0.001, ∣log2ratio∣≥1) of silkworm larvae during early response against B. bassiana infection. Total 1430 DEGs including 960 up-regulated and 470 down-regulated ones were identified, of which 627 DEGs can be classified into GO categories by Gene Ontology (GO) analysis. KEGG pathways analysis of these DEGs suggested that many biological processes, such as defense and response, signal transduction, phagocytosis, regulation of gene expression, RNA splicing, biosynthesis and metabolism, protein transport etc. were involved in the interaction between the silkworm and B. bassiana. A number of differentially expressed fungal genes were also identified by mapping the sequencing tags to B. bassiana genome. These results provided new insights to the molecular mechanism of silkworm immune response to B. bassiana infection. [ABSTRACT FROM AUTHOR]

A novel Bombyx mori cypovirus 1 isolated from infected silkworm larvae and tentatively assigned as Bombyx mori cypovirus 1 isolate Suzhou (BmCPV-SZ). The complete nucleotide sequences of genomic segments S1-S10 from BmCPV-SZ were determined. All segments possessed a single open reading frame; however, bioinformatic evidence suggested a short overlapping coding sequence in S1. Each BmCPV-SZ segment possessed the conserved terminal sequences AGUAA and GUUAGCC at the 5′ and 3′ ends, respectively. The conserved A/G at the -3 position in relation to the AUG codon could be found in the BmCPV-SZ genome, and it was postulated that this conserved A/G may be the most important nucleotide for efficient translation initiation in cypoviruses (CPVs). Examination of the putative amino acid sequences encoded by BmCPV-SZ revealed some characteristic motifs. Homology searches showed that viral structural proteins VP1, VP3, and VP4 had localized homologies with proteins of Rice ragged stunt virus, a member of the genus Oryzavirus within the family Reoviridae. A phylogenetic tree based on RNA-dependent RNA polymerase sequences demonstrated that CPV is more closely related to Rice ragged stunt virus and Aedes pseudoscutellaris reovirus than to other members of Reoviridae, suggesting that they may have originated from common ancestors. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the effects of gain of ecdysteroid UDP-glucosyltransferase (EGT) gene function mutation on the development of the silkworm, Bombyx mori. A novel piggyBac-derived plasmid containing the egt gene from B. mori nucleopolyhedrovirus (BmNPV) driven by a heat-shock protein (hsp) 23.7 promoter, with a neomycin-resistance gene (neo) controlled by the BmNPV ie-1 promoter and a green fluorescent protein gene (gfp) under the control of the B. mori actin 3 (A3) promoter was constructed. The vector was transferred into silkworm eggs by sperm-mediated gene transfer. Transgenic silkworms were produced after screening for neo and gfp genes and gene transfer was verified by polymerase chain reaction, dot-blot hybridization and western blotting. The hatching rate of G1 generation silkworm eggs was about 60% lower than that of normal silkworm eggs. The duration of the G1 generation larval period was extended, and the G2 generation pupal stage lasted four days longer than that in non-transgenic silkworms. The ecdysone blood level in G2 silkworms in the third instar molting stage was reduced by up to 90%. These results show that EGT suppressed transgenic silkworm molting, and that egt expression in egt-transgenic silkworms resulted in arrest of metamorphosis from pupae to moths. [Copyright &y& Elsevier]

The Lucaogou Formation in Jimuaser Sag of Junggar Basin, China is a typical tight oil reservoir with upper and lower sweet spots. However, the pore structure of this formation has not been studied thoroughly due to limited core analysis data. In this paper, the pore structures of the Lucaogou Formation were characterized, and a new method applicable to oil-wet rocks was verified and used to consecutively predict pore structures by nuclear magnetic resonance (NMR) logs. To do so, a set of experiments including X-ray diffraction (XRD), mercury intrusion capillary pressure (MICP), scanning electron microscopy (SEM) and NMR measurements were conducted. First, SEM images showed that pore types are mainly intragranular dissolution, intergranular dissolution, micro fractures and clay pores. Then, capillary pressure curves were divided into three types (I, II and III). The pores associated with type I and III are mainly dissolution and clay pores, respectively. Next, the new method was verified by "as received" and water-saturated condition T2 distributions of two samples. Finally, consecutive prediction in fourteen wells demonstrated that the pores of this formation are dominated by nano-scale pores and the pore structure of the lower sweet spot reservoir is more complicated than that in upper sweet spot reservoir. [ABSTRACT FROM AUTHOR]