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Nanoparticles have the capability to effectively improve the thermal conductivity of base fluids, thus improving the heat transfer coefficient of heat transfer systems. In this study, a non-equilibrium molecular dynamics method based on the Fourier law is employed to study the thermal conductivity of TiO2 (r-TiO2)-water nanofluids with temperatures ranging between 303 K and 333 K and volume fractions in the range of 1%-2%. The ordered layer structure as a shell is analyzed and its influence is surveyed by calculating the number density and radial distribution function. The results revealed that a clear, solid-like nanolayer of about 0.5 nm can be observed around the nanoparticle. In this regard, the thickness of the nanolayer is less affected by variations in volume fraction and temperature. The g(r) values and the number density decreased with the increase in temperature. Additionally, the g(r) values and the number density at the level of the nanolayer were much higher compared to those at other parts. This indicates the existence of more water molecules in the nanolayer, thereby reducing contact thermal resistance and improving thermal conductivity. Macroscopically, the thermal conductivity increases with the increase in volume fraction. It was found that the increase in the volume fraction from 1%-2% at 303 K resulted in an increase in the effective thermal conductivity from 1.027 and 1.042, respectively. In other words, the thermal conductivity of the nanofluid was 2.7% and 4.2% higher than that of the base liquid under the same conditions. [ABSTRACT FROM AUTHOR]

Significance: Endoscopic screening for esophageal cancer (EC) may enable early cancer diagnosis and treatment. While optical microendoscopic technology has shown promise in improving specificity, the limited field of view (<1 mm) significantly reduces the ability to survey large areas efficiently in EC screening. Aim: To improve the efficiency of endoscopic screening, we propose a novel concept of end-expandable endoscopic optical fiber probe for larger field of visualization and for the first time evaluate a deep-learning-based image super-resolution (DL-SR) method to overcome the issue of limited sampling capability. Approach: To demonstrate feasibility of the end-expandable optical fiber probe, DL-SR was applied on simulated low-resolution microendoscopic images to generate super-resolved (SR) ones. Varying the degradation model of image data acquisition, we identified the optimal parameters for optical fiber probe prototyping. The proposed screening method was validated with a human pathology reading study. Results: For various degradation parameters considered, the DL-SR method demonstrated different levels of improvement of traditional measures of image quality. The endoscopists’ interpretations of the SR images were comparable to those performed on the high-resolution ones. Conclusions: This work suggests avenues for development of DL-SR-enabled sparse image reconstruction to improve high-yield EC screening and similar clinical applications. [ABSTRACT FROM AUTHOR]

The lance is a critical component of the bottom-blowing pool melting process, and its placement has an important impact on the pool's gas-liquid two-phase flow. In this study, a mathematical model of the bottom-blowing process is established, and the flow pattern, trajectory, wake vortex, and velocity of bubbles under four lance spacings are simulated. Results show that there are three basic bubble flow patterns appear in the flow field: bubbles coalesce before leaving the nozzle (Pattern II), bubbles coalesce after leaving the nozzle (Pattern I), and no coalescence during the rise of bubbles (Pattern III). The bubble pattern varies from Pattern I to Pattern III with the increase in lance spacing. The intensity of the influence of the wake vortex on the bubbles decreases. The Q (the Q is the second Galilean invariant of the velocity gradient tensor ∇v) value of the wake vortex is small, but the vortex structural distribution is complex. Moreover, there is a large velocity difference between gas and liquid at the beginning of gas injection, but the velocity difference between them decreases after gas injection, so the average turbulent kinetic energy in the pool initially increases sharply, and then approaches dynamic equilibrium. The top and bottom velocities of the bubbles are consistent, and the velocity fluctuation is orderly. Moreover, the greater the lance spacing is, the greater the disturbance in the pool is. The mixing effect of D = 0.2 m is the best among the four spacings. [ABSTRACT FROM AUTHOR]

Recognizing terminal ridge subduction is of first-order importance in chronicling the tectonic timeline of any accretionary orogens, but remains elusive in the final suturing zone of the Paleo-Asian Ocean along the Solonker-- Xar Moron--Changchun--Yanji swath. Here we report two generations of ultramaficmafic to intermediate intrusions from northern Liaoning, North China, linking eastern Central Asian Orogenic Belt and northern North China Craton. The ca. 259 Ma appinites show variable enrichment in large-ion lithophile elements (LILEs) but depletion in high-field strength elements (HFSEs), and variably enriched isotopic compositions with εNd(t) of -11.8 to -2.4 and zircon εHf(t) of -15.7 to +5.0. These petro-geochemical traits argue for their derivation from partial melting of subduction-modified lithospheric mantle. By contrast, the high-Mg diorites of 226-223 Ma display decoupling features between LILEs and HFSEs and juvenile isotopic signatures with εNd(t) of -0.3 to +2.6 and zircon εHf(t) of +5.4 to +11.4. These characters are consistent with a magmatic origin from partial fusion of sediment-fertilized asthenospheric mantle. Synthesizing the two mantle-melting events with regional coeval igneous activities leads to the identification of Late Permian (265-250 Ma) and Middle-Late Triassic (241-218 Ma) magmatic flare-ups with a 10-15 m.y. lull along the northern North China Craton. This magmatic tempo tends to record a salient mantle replacement from hydrous metasomatized lithosphere to anhydrous asthenosphere. In combination with ensuing progressive crustal growth, simultaneous metamorphism, and structural activities, these diverse manifestations make a compelling case of ridge subduction and concomitant slab window formation during the eventual closure of the Paleo-Asian Ocean along the Solonker--Xar Moron--Changchun--Yanji swath. [ABSTRACT FROM AUTHOR]

Mutations in the HERC2 and OCA2 genes have the potential to affect pigment deposition and alter feather color in birds. Therefore, in this study, we evaluated HERC2-OCA2 gene locus polymorphisms in Korean and Beijing white quails using RNA-Seq and KASP technology. The expression levels of HERC2 and OCA2 mRNA in skin tissues were analyzed using RT-qPCR. Ten single nucleotide polymorphisms were identified by RNA-Seq, of which three (n.117627564T>A, n.117674275T>G, n.117686226A>C) exhibited significant association with feather color in quail. The expression of OCA2 mRNA was significantly lower in the skin of Beijing white quails than that in the skin of Korean quails. These results suggested that variants in HERC2-OCA2 intergenic region could influence the expression of OCA2, which may underlie diluted feather color in the Beijing white quail. [ABSTRACT FROM AUTHOR]

In order to study the movement and shape change characteristic of bubble when passing through the interface of two kinds of liquids with different viscosity, the free rising process of a single bubble in static stratified liquids was numerically simulated with the volume-of-fluid method. The results show that, when the initial height of bubble rising is the same, the rising velocity, deformation increase with the increase of bubble radius. When the maximum intensity of the vortex in the bubble is distributed at the top of the bubble, the top of the left and right sides and the bottom of the left and right sides, the bubble shape is spherical, ellipsoid and spherical cap shape respectively. At different initial heights, the bubble trajectory shows three different shapes – linear, spiral, and C-shaped. The relationship between the bubble aspect ratio and rising height is predicted when different radius bubble passing through the interface. The amount of liquid B (lower layer) carried by the bubble increases with the increase of the bubble’s initial radius, and the amount of liquid carried by bubbles in C-shaped trajectory is higher than that in spiral trajectory. [ABSTRACT FROM AUTHOR]

Context.--In the 2017 revised World Health Organization classification of tumors of hematopoietic and lymphoid tissues, some mature T-cell lymphomas were reclassified and a few new provisional entities were established based on new data from clinical and laboratory studies. T follicular helper cell lymphoma is identified by T follicular helper cell markers. Anaplastic large cell lymphoma, ALK negative, is a better-defined entity based on genetic abnormalities, and breast implant--associated anaplastic large cell lymphoma is recognized as a provisional entity. The gastrointestinal T-cell lymphomas are reclassified, with addition of a new provisional entity, indolent T-cell lymphoproliferative disorder of the gastrointestinal tract, characterized by an indolent clinical course. Objective.--To review the diagnostic approaches to reclassified and newly established entities of mature T-cell lymphomas, focusing on significant immunophenotypic features and molecular genetic abnormalities. Relevant new discoveries after the publication of the 2017 World Health Organization classification are included. Data Sources.--Information from the literature most relevant to the 2017 World Health Organization revised classification and publications after 2016. Conclusions.--Incorporating clinical, morphologic, and immunophenotypic features usually provides sufficient evidence to reach a preliminary diagnosis of mature T-cell lymphoma. Molecular genetic studies can be very helpful for the final diagnosis and classification, especially in challenging cases. Some molecular genetic features have been found in breast implant--associated anaplastic large cell lymphoma, distinct from anaplastic large cell lymphoma, ALK negative. Immunohistochemical staining of 4 markers may enable further subtyping of peripheral T-cell lymphomas. [ABSTRACT FROM AUTHOR]

It is of great significance to investigate the rising behavior of a bubble in immiscible fluids in chemical and metallurgical engineering. A 3-D model is established and the free-floating behavior of a single bubble in immiscible fluids (water- heavier liquid and biodiesel-lighter liquid) is numerically simulated by phase-field method. After the fluctuation of a certain distance, the bubble tends to be stable. It takes more time for the larger bubble to reach a stable shape than for the smaller one. The terminal aspect ratio of bubble, ET, with the same size in heavier liquid is smaller than that in lighter liquid. With the increase of bubble size, ET becomes small both in heavier and lighter liquid. Comparing bubble vortex diagrams of different shapes shows that the maximum vortex intensity is the direction in which the bubble shape extends. When the bubble passes through the liquid-liquid interface, it will form "pear", "inverted pear", "convex", and "water drop" shapes successively. [ABSTRACT FROM AUTHOR]

In order to improve the energy-saving level of commercial buildings' air-conditioning units with double cold sources and reduce the energy cost, an energy-saving optimal control method of commercial buildings' air-conditioning units with double cold sources based on self-organizing neural network is proposed. Constrained parameter model of energy-saving control of commercial buildings' double-cold-source air-conditioning units is constructed. Taking the balanced real-time dynamic adjustment characteristic quantity of inverter of commercial buildings' double-cold-source air-conditioning units as the control object, combined with the fuzzy constraint method of variable frequency speed adjustment parameters and stroke adjustment power of commercial buildings' double-coldsource air-conditioning units, the steady-state adjustment of energy-saving output of commercial buildings' double-cold-source air-conditioning units is realized, and the self-organizing neural network control model of periodic potential energy load of building HVAC system is established. Combined with the small disturbance suppression method of motor rated power, the optimal control design of energy-saving of commercial buildings. The simulation results show that the output stability of the energy-saving control of commercial building air-conditioning units with double cold sources is good, the steady-state working ability is strong, and the energy-saving effect of commercial building air-conditioning units with double cold sources is good. [ABSTRACT FROM AUTHOR]

In the movement process of continuous bubbles, different liquid-flow state and initial temperature of bubbles have important influence on bubble movement and heat transfer. In this study, the flow and heat transfer characteristics of high temperature bubbles in normal temperature liquid are investigated. The rising process of and temperature of bubbles are studied by numerical simulation and compared with experimental results for verification. The results show that the shape, velocity and temperature of the bubble are affected by the initial position of the bubble. Because the closer the initial position of the bubble is to the bottom of the cylinder, the greater decrease of the bubble aspect ratio, w*, the faster decrease of bubble temperature, and the larger bubble velocity would be. The increase of the bubble diameter would mitigate the influence of liquid jet on the bubble motion. Finally, as the bubble surface tension increases, the liquid jet would have less influence on the bubble movement. [ABSTRACT FROM AUTHOR]

The method based on machine vision image processing is used to detect the surface defects of Si 3 N 4 bearing roller. Owing to the variety of defects, small area and low contrast, it is easy to miss or error detection. In this paper, an adaptive update template defect enhancement algorithm based on Gaussian model is proposed. First, a large number of surface images of Si 3 N 4 bearing roller are collected to obtain the non-defect background statistical feature, and the background characteristic curve is fitted by Gaussian model. Further, the initial background template is gained according to the Gaussian curve. Then, combined with the gray distribute of defect images and initial background template, unique adaptive update template can be established. Finally, subtraction operation and nonlinear enhancement are used to improve the comparison of defect information and background. Through inverse sorting, adaptive threshold segmentation and Canny operation, the precise positioning of defects is realized. The enhancement algorithm can effectively enhance the contrast and eliminate the influence of noise. The average detection time is 0.84s, and the detection accuracy is 96.2%. [ABSTRACT FROM AUTHOR]

Updating magmatic profile in crucial constituent terranes across the Central Asian Orogenic Belt presents a key to chronicling the timeline of prolonged accretionary processes and termination of the Paleo-Asian Ocean in the northern China-southern Mongolia tract. Here we performed a systematic geochronological and geochemical study on a spectrum of Paleozoic intrusions from the Erenhot region in central Inner Mongolia, North China, within the hinterland of the tract, with four distinct magmatic episodes unraveled. Combining these episodes with the previously documented events from contiguous regions defines two major tectono-magmatic cycles. The early Paleozoic cycle (500-450 Ma) evolved from initial fluid-fluxed tholeiitic and calc-alkaline granitoids to melt-fertilized mafic-intermediate magmatism. It appears to experience the initiation and maturation of a Western Pacifictype intra-oceanic arc system that culminated in ridge subduction. The late Paleozoic cycle expanded in magmatic expression from sporadic Late Devonian (373-365 Ma) calcalkaline intermediate-felsic pulses through Early-Middle Carboniferous (356-320 Ma) medium to high-K calc-alkaline flare-up to a Late Carboniferous-Early Permian (310-277 Ma) province of diverse lithologies. These magmatic episodes seem to encompass a complete active continental arc-back-arc system that spanned from resuming oceanic plate subduction through slab rollback and backarc rifting to ridge-trench collision and backarc basin closure. Featuring a Rodiniaaged terrane affinity and a representative Paleozoic magmatic profile, the Erenhot region provides an optimal site for correlating the evolution of mosaic terranes in southern Mongolia and northern China, and for evaluating the coupled evolution of shifting tectonic regimes and plural crustal generation mechanisms within a retreating accretionary orogen. [ABSTRACT FROM AUTHOR]

For a ∈ (0,1) and r ∈ (0,1), let Ea(r) be the generalized elliptic integral of the second kind and R(a) be Ramanujan's constant. In this paper, we prove the following inequalities sin(πa) 2(1-a) +r'2 (1-a)sin(πa)log e R(a)/2 r ! -σ ! < Ea(r) < sin(πa) 2(1-a) +r 2 (1-a)sin(πa)log e R(a)/2 r ! -δ ! with the best possible constants σ = 1 4 sin(πa) and δ = sin(πa) 2(1-a) + (1-a)sin(πa) R(a) 2 - π 2. [ABSTRACT FROM AUTHOR]

Background: Genomic sequencing of T. pallidum subsp. pallidum (TPA) strains from clinical specimens is critical for epidemiological surveillance and vaccine development. While genome sequences have been obtained directly from clinical samples from early syphilis patients and from rabbit passaged isolates, the two have not been done in parallel for the same individuals. We compared genomic sequences of TPA in clinical samples and following rabbit passage. Methods: We recruited primary (PS) and secondary (SS) syphilis patients > 18 years from a dermatology hospital in Guangzhou, China between November 2019- May 2022. We collected ulcer exudates and whole blood specimens from PS patients and skin biopsy and whole blood specimens from SS patients. Quantitative PCR (qPCR) was performed on DNA extracted from these clinical specimens. Ulcer exudates from PS and whole blood specimens from SS also were used for isolation of TPA strains by rabbit infectivity testing (RIT). TPA enrichment using RNA oligonucleotide baits and whole-genome sequencing (WGS) were performed on ulcer exudates and biopsy specimens and on the corresponding rabbit-isolated TPA strains. Results: During the study period, 69 patients were enrolled; 18 had PS and 51 had SS. The specimens collected, TPA qPCR and RIT results are summarized in the Table. Twenty-five paired TPA genomes from clinical samples and rabbit-passaged isolates were compared. In the 23 paired SS14-lineage strains, 8 contained single nucleotide variants (SNV) (1~3 SNVs per paired genome); 3 of these unique SNVs caused amino acid changes. In the 2 paired Nichols-lineage strains, we observed 5 and 15 SNVs per paired genomes respectively, of which 14 of 20 SNVs were non-synonymous coding. Most variants were identical in the TPA genomes derived from clinical and rabbit-passaged samples. Based on the genomic sequences from samples and rabbit passaged strains, there was no evidence for co-infection with more than one strain. Conclusions: Our study showed that RIT was effective in isolating TPA strains from early syphilis clinical specimens, including blood. WGS data suggest that sequences from rabbit-passaged isolates and clinical specimens are very similar, although slight variation of genomes requiring further investigation was observed. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) have been found in both surface water and groundwater, which are sources of drinking water. Since one of the most important routes for MPs to enter the human body is through drinking water, the enormous buildup of MPs in waterbodies and the resulting effects on human health have caused social concern. However, our knowledge of drinking water treatment plant (DWTP) treatment techniques affects the removal of MPs, and there aren't any standardized or efficient quality assurance and quality control (QA/QC) measures for sampling and analysis. The current state of MPs in drinking water sources is described in this review, which also provides the most recent data on MPs removal by various DWTP units. Lastly, we propose practical QA/QC techniques to ensure the accuracy of MP analysis. This review intends to present the most recent data on MPs in drinking water and the effectiveness of MPs removal by DWTP units. It also advises that further research into the mechanisms of MPs removal be done in the future. [ABSTRACT FROM AUTHOR]

Background: Appropriate passive-active immunoprophylaxis effectively reduces mother-to-child transmission (MTCT) of hepatitis B virus (HBV), but the immunoprophylaxis failure was still more than 5% under the current strategy. The study objective was to investigate the effects of high dose of HB vaccine on MTCT and immune response for infants born to hepatitis B surface antigen (HBsAg)-positive mothers.Methods: This was a prospective, multicenter, large-sample cohort study in four sites of China, and 955 pairs of HBsAg-positive mothers and their infants were enrolled in our investigation. The infants were given 10 μg or 20 μg HB vaccine (at age 0, 1, and 6 months) plus HB immunoglobulin (at age 0 and 1 month). Serum HBsAg, antibody to HBsAg (anti-HBs), and/or HBV DNA levels in the infants were determined at age 12 months. The safety of 20 μg HB vaccine was evaluated by adverse events and observing the growth indexes of infants.Results: Thirteen of 955 infants were HBsAg-positive at 12 months. Stratification analysis showed that immunoprophylaxis failure rates in the 20 μg group were not significantly different from the 10 μg group, whatever maternal HBV load was high or not. But the high dose of HB vaccine significantly reduced low-response rate (anti-HBs 10-100 IU/L) (P = 0.002) and middle-response rate (anti-HBs 100-1000 IU/L) (P = 0.022) and improved high-response rate (anti-HBs ≥ 1000 IU/L) (P < 0.0001) in infants born to mothers with HBV DNA < 5 log10 IU/mL. For infants born to mothers with HBV DNA ≥ 5 log10 IU/mL, 20 μg HB vaccine did not present these above response advantages. The 20 μg HB vaccine showed good safety for infants.Conclusions: The 20 μg HB vaccine did not further reduce immunoprophylaxis failure of infants from HBsAg-positive mothers, but increased the high-response and decreased low-response rates for infants born to mothers with HBV DNA < 5 log10 IU/mL.Trial Registration: Chinese Clinical Trial Registry, ChiCTR-PRC-09000459. [ABSTRACT FROM AUTHOR]

A missense mutation of collagen type VIII alpha 2 chain (COL8A2) gene leads to early-onset Fuchs' endothelial corneal dystrophy (FECD), which progressively impairs vision through the loss of corneal endothelial cells. We demonstrate that CRISPR/Cas9-based postnatal gene editing achieves structural and functional rescue in a mouse model of FECD. A single intraocular injection of an adenovirus encoding both the Cas9 gene and guide RNA (Ad-Cas9-Col8a2gRNA) efficiently knocked down mutant COL8A2 expression in corneal endothelial cells, prevented endothelial cell loss, and rescued corneal endothelium pumping function in adult Col8a2 mutant mice. There were no adverse sequelae on histology or electroretinography. Col8a2 start codon disruption represents a non-surgical strategy to prevent vision loss in early-onset FECD. As this demonstrates the ability of Ad-Cas9-gRNA to restore the phenotype in adult post-mitotic cells, this method may be widely applicable to adult-onset diseases, even in tissues affected with disorders of non-reproducing cells. [ABSTRACT FROM AUTHOR]

Background: In plant genomes, high proportions of duplicate copies reveals that gene duplications play an important role in the evolutionary processes of plant species. A series of gene families under positive selection after recent duplication events in plant genomes indicated the evolution of duplicates driven by adaptive evolution. However, the genome-wide evolutionary features of young duplicate genes among closely related species are rarely reported. Results: In this study, we conducted a systematic survey of young duplicate genes at genome-wide levels among six Rosaceae species, whose whole-genome sequencing data were successively released in recent years. A total of 35,936 gene families were detected among the six species, in which 60.25% were generated by young duplications. The 21,650 young duplicate gene families could be divided into two expansion types based on their duplication patterns, species-specific and lineage-specific expansions. Our results showed the species-specific expansions advantaging over the lineage-specific expansions. In the two types of expansions, high-frequency duplicate domains exhibited functional preference in response to environmental stresses. Conclusions: The functional preference of the young duplicate genes in both the expansion types showed that they were inclined to respond to abiotic or biotic stimuli. Moreover, young duplicate genes under positive selection in both species-specific and lineage-specific expansions suggested that they were generated to adapt to the environmental factors in Rosaceae species. [ABSTRACT FROM AUTHOR]

Cyanobacteria experience drastic changes in their carbon metabolism under daily light/dark cycles. During the day, the Calvin-Benson cycle fixes CO2 and diverts excess carbon into glycogen storage. At night, glycogen is degraded to support cellular respiration. The dark/light transition represents a universal environmental stress for cyanobacteria and other photosynthetic lifeforms. Recent studies revealed the essential genetic background necessary for the fitness of cyanobacteria during diurnal growth. However, the metabolic processes underlying the dark/light transition are not well understood. In this study, we observed that glycogen metabolism supports photosynthesis in the cyanobacterium Synechococcus elongatus PCC 7942 when photosynthesis reactions start upon light exposure. Compared with the wild type, the glycogen mutant ΔglgC showed a reduced photosynthetic efficiency and a slower P700+ rereduction rate when photosynthesis starts. Proteomic analyses indicated that glycogen is degraded through the oxidative pentose phosphate (OPP) pathway during the dark/light transition. We confirmed that the OPP pathway is essential for the initiation of photosynthesis and further showed that glycogen degradation through the OPP pathway contributes to the activation of key Calvin-Benson cycle enzymes by modulating NADPH levels. This strategy stimulates photosynthesis in cyanobacteria following dark respiration and stabilizes the Calvin-Benson cycle under fluctuating environmental conditions, thereby offering evolutionary advantages for photosynthetic organisms using the Calvin-Benson cycle for carbon fixation. [ABSTRACT FROM AUTHOR]

Heat stress (HS) often causes sudden death of humans and animals due to heart failure, mainly resulting from the contraction of cardiac microvasculature followed by myocardial ischemia. Cardiac microvascular endothelial cells (CMVECs) play an important role in maintaining vasodilatation. Aspirin (ASA) is well known for its protective abilities of febrile animals. However, there is little knowledge about molecular resistance mechanisms of CMVECs and which role ASA may play in this context. Therefore, we used a heat stress model of rat cardiac microvascular endothelial cell cultures in vitro and investigated the cell injuries and molecular resistance mechanism of CMVECs caused by heat stress, and the effect of aspirin (ASA) on it. HS induced severe pathological damage of CMVECs and cellular oxidative stress and dysfunction of NO release. Hsp90 was proven to be indispensable for resisting HS-injury of CMVECs through PI3K-Akt and PKM2 signaling pathways. Meanwhile, PKM2 functioned in reducing Akt phosphorylation. ASA treatment of CMVECs induced a significant expression of Hsp90, which promoted both Akt and PKM2 signals, which are beneficial for relieving HS damage and maintaining the function of CMVECs. Akt activation also promoted HSF-1 that regulates the expression of Hsp70, which is known to assist Hsp90′s molecular chaperone function and when released to the extracellular liquid to protect myocardial cells from HS damage. To the best of our knowledge, this is the first study to show that HS damages CMVECs and the protection mechanism of Hsp90 on it, and that ASA provides a new potential strategy for regulating cardiac microcirculation preventing HS-induced heart failure. [ABSTRACT FROM AUTHOR]

This study extended the knowledge over the improvement of the control performance for a seven degrees-of-freedom (7DOF) humanoid arm. An improved adaptive Gaussian radius basic function neural network (RBFNN) approach was proposed to ensure the reliability and stability of the humanoid arm control. Considering model uncertainties, the established dynamic model for the humanoid arm was divided into a nominal model and an error model. The error model was approximated by the RBFNN learning to compensate the uncertainties. The contribution of this study mainly concentrates on employing fruit fly optimization algorithm (FOA) to optimize the basic width parameter of the RBFNN, which can enhance the capability of the error approximation speed. Additionally, the output weights of the neural network were adjusted using the Lyapunov stability theory to improve the robustness of the RBFN-based error model. The simulation and experiment results demonstrate that the proposed approach is able to optimize the system state with less tracking errors, regulate the uncertain nonlinear dynamic characteristics, and effectively reduce unexpected interferences. [ABSTRACT FROM AUTHOR]

This study extended the knowledge over the improvement of the control performance for a seven degrees-of-freedom (7DOF) humanoid arm. An improved adaptive Gaussian radius basic function neural network (RBFNN) approach was proposed to ensure the reliability and stability of the humanoid arm control. Considering model uncertainties, the established dynamic model for the humanoid arm was divided into a nominal model and an error model. The error model was approximated by the RBFNN learning to compensate the uncertainties. The contribution of this study mainly concentrates on employing fruit fly optimization algorithm (FOA) to optimize the basic width parameter of the RBFNN, which can enhance the capability of the error approximation speed. Additionally, the output weights of the neural network were adjusted using the Lyapunov stability theory to improve the robustness of the RBFN-based error model. The simulation and experiment results demonstrate that the proposed approach is able to optimize the system state with less tracking errors, regulate the uncertain nonlinear dynamic characteristics, and effectively reduce unexpected interferences. [ABSTRACT FROM AUTHOR]

• A semi–analytical force–method solution for a straight–jointed tunnel is proposed. • Nonlinear joint stiffness is considered and expressed as a function of M, N and θ. • An incremental iterative algorithm is established for the strong nonlinear system. • The tunnel ultimate bearing capacity under different load distributions is analyzed. The ultimate bearing capacity of a segmental tunnel lining significantly influences its service performance, particularly when the surrounding soil pressure changes. In this study, a semi–analytical force–method solution for a straight–jointed segmental tunnel lining was derived. The nonlinear joint stiffness was considered and expressed as a function of the bending moment, axial force, and rotational angle of the joint. An incremental iterative algorithm and the corresponding convergence criterion of the proposed model were established for the strong nonlinear system. The proposed model was then verified using the full–scale test results for the loading behavior of the joint and the segmental lining. The structural response of the tunnel under different external load distributions was analyzed using the proposed model, and the main conclusions are as follows. As the lateral pressure coefficient increases, the ultimate bearing capacity of the tunnel lining increases and the length of the first yield platform of the convergence deformation decreases. When P 3 /P 1 increases from 0.71 to 0.83, the ultimate bearing capacity of the tunnel lining increases by 20%, but it has no significant effect on the ultimate convergence deformation. For the lining of the shield tunnel of the Shanghai Metro, the recommended convergent deformation limit is 110 mm. [ABSTRACT FROM AUTHOR]

Background: Plant disease resistance (R) genes are evolving rapidly and play a critical role in the innate immune system of plants. The nucleotide binding sites-leucine rich repeat (NBS-LRR) genes are one of the largest classes in plant R genes. Previous studies have focused on the NBS-LRR genes from one or several species of different genera, and the sequenced genomes of the genus Fragaria offer the opportunity to study the evolutionary processes of these R genes among the closely related species. Results: In this study, 325, 155, 190, 187, and 133 NBS-LRRs were discovered from F. x ananassa, F. iinumae, F. nipponica, F. nubicola, and F. orientalis, respectively. Together with the 144 NBS-LRR genes from F. vesca, a total of 1134 NBS-LRRs containing 866 multi-genes comprised 184 gene families across the six Fragaria genomes. Extremely short branch lengths and shallow nodes were widely present in the phylogenetic tree constructed with all of the NBS-LRR genes of the six strawberry species. The identities of the orthologous genes were highly significantly greater than those of the paralogous genes, while the Ks ratios of the former were very significantly lower than those of the latter in all of the NBS-LRR gene families. In addition, the Ks and Ka/Ks values of the TIR-NBS-LRR genes (TNLs) were significantly greater than those of the non-TIR-NBS-LRR genes (non-TNLs). Furthermore, the expression patterns of the NBS-LRR genes revealed that the same gene expressed differently under different genetic backgrounds in response to pathogens. Conclusions: These results, combined with the shared hotspot regions of the duplicated NBS-LRRs on the chromosomes, indicated that the lineage-specific duplication of the NBS-LRR genes occurred before the divergence of the six Fragaria species. The Ks and Ka/Ks ratios suggested that the TNLs are more rapidly evolving and driven by stronger diversifying selective pressures than the non-TNLs. [ABSTRACT FROM AUTHOR]

Cucumber (Cucumis sativus L.) is characterized by its diverse and flexible sexual types. Here, we evaluated the effect of low temperature (LT) exposure on cucumber femaleness under short-day conditions. Shoot apices were subjected to whole-genome bisulfate sequencing (WGBS), mRNA-seq, and sRNA-seq. The results showed that temperature had a substantial and global impact on transposable element (TE)-related small RNA-directed DNA methylation (RdDM) mechanisms, resulting in large amounts of CHH-type cytosine demethylation. In the cucumber genome, TEs are common in regions near genes that are also subject to DNA demethylation. TE-gene interactions showed very strong reactions to LT treatment, as nearly 80% of the differentially methylated regions (DMRs) were distributed in genic regions. Demethylation near genes led to the co-ordinated expression of genes and TEs. More importantly, genome-wide de novo methylation changes also resulted in small amounts of CG- and CHG-type DMRs. Methylation changes in CG-DMRs located <600 bp from the transcription start and end sites (TSSs/TESs) negatively correlated with transcription changes in differentially expressed genes (DEGs), probably indicating epiregulation. Ethylene is called the 'sex hormone' of cucumbers. We observed the up-regulation of ethylene biosynthesis-related CsACO3 and the down-regulation of an Arabidopsis RAP2.4-like ethylene-responsive (AP2/ERF) transcription factor, demonstrating the inferred epiregulation. Our study characterized the response of the apex methylome to LT and predicted the possible epiregulation of temperature-dependent sex determination (TSD) in cucumber. [ABSTRACT FROM AUTHOR]

Human MutT homolog 1 (MTH1) detoxifies the oxidized DNA precursor 8-oxo-2'-deoxyguanosine-5'-triphosphate and serves a tumor suppressive role in distinct types of cancer. In the present study, the expression of MTH1 was examined in various subtypes of breast cancer, and the effect of its suppression on breast cancer growth was characterized in vitro and in vivo. MTH1 mRNA and protein levels were assessed using the reverse transcription-quantitative polymerase chain reaction and immunohistochemistry. The effect of MTH1 expression on the proliferation of breast cancer cells was investigated in vitro using Cell Counting Kit-8 and colony formation assays, and in vivo using breast cancer cell line xenografts in mice. The toxicity of the MTH1 inhibitor TH588 was investigated in nude mice. A marked increase in MTH1 protein and mRNA levels was demonstrated in breast cancer tissues compared with the non-cancerous control. However, no apparent differences in MTH1 expression were observed between distinct molecular subtypes of breast cancer. MTH1 overexpression was demonstrated to be independent of patient age, tumor size and lymph node metastasis. Inhibition of MTH1 decreased cancer cell viability and the clonogenic potential of cancer cells in a dose-dependent manner. These results were confirmed by decreased in vivo proliferation of MCF7, MDA-MB-231 and MDA-MB-453 cancer cell lines, representing distinct subtypes of breast cancer. Although inhibition of MTH1 activity decreased xenograft growth in mice, no major adverse effects of TH588 were detected on the basis of blood biochemistry, and liver and kidney function. The results of the present study suggested that MTH1 is overexpressed in the majority of breast cancers, independent of the molecular identity and clinicopathological features of the tumor, including patient age, tumor size and lymph node metastasis. Inhibition of MTH1 activity suppressed the growth of three subtypes of breast cancer, including luminal, basal-like and human epidermal growth factor receptor 2-positive, in vitro and in vivo. Treatment with the MTH1 inhibitor appears to be safe; however, further studies are required prior to the clinical use of MTH1 inhibitors. [ABSTRACT FROM AUTHOR]

Ni/NiO nanoflower modified reduced graphene oxide (rGO) nanocomposite (Ni/NiO-rGO) was introduced to screen printed electrode (SPE) for the construction of a nonenzymatic electrochemical glucose biosensor. The Ni/NiO-rGO nanocomposite was synthesized by an in situ reduction process. Graphene oxide (GO) hybrid Nafion sheets first chemical adsorbed Ni ions and assembled on the SPE. Subsequently, GO and Ni ions were reduced by hydrazine hydrate. The electrochemical properties of such a Ni/NiO-rGO modified SPE were carefully investigated. It showed a high activity for electrocatalytic oxidation of glucose in alkaline medium. The proposed nonenzymatic sensor can be utilized for quantification of glucose with a wide linear range from 29.9 μM to 6.44 mM (R = 0.9937) with a low detection limit of 1.8 μM (S/N = 3) and a high sensitivity of 1997 μA/mM·cm-2. It also exhibited good reproducibility as well as high selectivity. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to provide a critical systematic review of the role of magnetic resonance imaging (MRI) as a noninvasive method to assess periprosthetic joint infections (PJIs). Methods: The electronic databases PubMed and EMBASE were searched, since their inception up to March 27, 2022. The included studies evaluated the reproducibility and accuracy of MRI features to diagnose PJIs. The article quality assessment was conducted by the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) and Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Results: Among 1909 studies identified in the initial search, 8 studies were eligible for final systematic review. The included studies evaluated the reproducibility and accuracy of MRI features to diagnose PJIs. Seven of 8 studies showed good to excellent reliability, but only one article among them in which accuracy was evaluated had a low risk of bias. The intraclass correlation coefficient (ICC) and Cohen coefficient (κ) varied between 0.44 and 1.00. The accuracy varied between 63.9% and 94.4%. Potential MRI features, such as lamellated hyperintense synovitis, edema, fluid collection, or lymphadenopathy, might be valuable for diagnosing PJIs. Conclusion: The quality of the evidence regarding the role of MRI for PJIs diagnosis was low. There is preliminary evidence that MRI has a noteworthy value of distinguishing suspected periprosthetic joint infection in patients with total knee arthroplasty or total hip arthroplasty, but the definition of specific MRI features related to PJIs diagnosis lacks consensus and standardization. Large-scale studies with robust quality were required to help make better clinical decisions in the future. [ABSTRACT FROM AUTHOR]

Background: Barbarea vulgaris contains two genotypes: the glabrous type (G-type), which confers resistance to the diamondback moth (DBM) and other insect pests, and the pubescent type (P-type), which is susceptible to the DBM. Herein, the transcriptomes of P-type B. vulgaris before and after DBM infestation were subjected to Illumina (Solexa) pyrosequencing and comparative analysis. Results: 5.0 gigabase pairs of clean nucleotides were generated. Non-redundant unigenes (33,721) were assembled and 94.1% of them were annotated. Compared with our previous G-type transcriptome, the expression patterns of many insect responsive genes, including those related to secondary metabolism, phytohormones and transcription factors, which were significantly induced by DBM in G-type plants, were less sensitive to DBM infestation in P-type plants. The genes of the triterpenoid saponin pathway were identified in both G- and P-type plants. The upstream genes of the pathway showed similar expression patterns between the two genotypes. However, gene expression for two downstream enzymes, the glucosyl transferase (UGT73C11) and an oxidosqualene cyclase (OSC), were significantly upregulated in the P-type compared with the G-type plant. The homologous genes from P- and G-type plants were detected by BLAST unigenes with a cutoff level E-value < e-10. 12,980 gene families containing 26,793 P-type and 36,944 G-type unigenes were shared by the two types of B. vulgaris. 38,397 single nucleotide polymorphisms (SNPs) were found in 9,452 orthologous genes between the P- and G-type plants. We also detected 5,105 simple sequence repeats (SSRs) in the B. vulgaris transcriptome, comprising mono-nucleotide-repeats (2,477; 48.5%) and triple-nucleotide-repeats (1,590; 31.1%). Of these, 1,657 SSRs displayed polymorphisms between the P- and G-type. Consequently, 913 SSR primer pairs were designed with a resolution of more than two nucleotides. We randomly chose 30 SSRs to detect the genetic diversity of 32 Barbarea germplasms. The distance tree showed that these accessions were clearly divided into groups, with the G-type grouping with available Western and Central European B. vulgaris accessions in contrast to the P-type accession, B. stricta and B. verna. Conclusions: These data represent useful information for pest-resistance gene mining and for the investigation of the molecular basis of plant-pest interactions. [ABSTRACT FROM AUTHOR]

Let (H, ɑ) be a monoidal Hom-Hopf algebra and (A, β) a right (H, ɑ)-Hom-comodule algebra. We first investigate the criterion for the existence of a total integral of (A, β) in the setting of monoidal Hom-Hopf algebras. Also, we prove that there exists a total ø integral : (H, ɑ) → (A, β) if and only if any representation of the pair (H, A) is injective in a functorial way, as a corepresentation of (H, ɑ), which generalizes Doi's result. Finally, we define a total quantum integral ɣ : H → Hom(H, A) and prove the following affineness criterion: if there exists a total quantum integral ɣ and the canonical map Ψ : A⊗B A → A ⊗ H, a⊗B b ↦ β-1(a)b[0] ⊗ ɑ(b[1]) is surjective, then the induction functor A⊗B-:H(Mk)B → H(Mk)AH is an equivalence of categories. [ABSTRACT FROM AUTHOR]

Background Cyanothece sp. PCC 7822 is an excellent cyanobacterial model organism with great potential to be applied as a biocatalyst for the production of high value compounds. Like other unicellular diazotrophic cyanobacterial species, it has a tightly regulated metabolism synchronized to the light-dark cycle. Utilizing transcriptomic and proteomic methods, we quantified the relationships between transcription and translation underlying central and secondary metabolism in response to nitrogen free, 12 hour light and 12 hour dark conditions. Results By combining mass-spectrometry based proteomics and RNA-sequencing transcriptomics, we quantitatively measured a total of 6766 mRNAs and 1322 proteins at four time points across a 24 hour light-dark cycle. Photosynthesis, nitrogen fixation, and carbon storage relevant genes were expressed during the preceding light or dark period, concurrent with measured nitrogenase activity in the late light period. We describe many instances of disparity in peak mRNA and protein abundances, and strong correlation of light dependent expression of both antisense and CRISPR-related gene expression. The proteins for nitrogenase and the pentose phosphate pathway were highest in the dark, whereas those for glycolysis and the TCA cycle were more prominent in the light. Interestingly, one copy of the psbA gene encoding the photosystem II (PSII) reaction center protein D1 (psbA4) was highly upregulated only in the dark. This protein likely cannot catalyze O2 evolution and so may be used by the cell to keep PSII intact during N2 fixation. The CRISPR elements were found exclusively at the ends of the large plasmid and we speculate that their presence is crucial to the maintenance of this plasmid. Conclusions This investigation of parallel transcriptional and translational activity within Cyanothece sp. PCC 7822 provided quantitative information on expression levels of metabolic pathways relevant to engineering efforts. The identification of expression patterns for both mRNA and protein affords a basis for improving biofuel production in this strain and for further genetic manipulations. Expression analysis of the genes encoded on the 6 plasmids provided insight into the possible acquisition and maintenance of some of these extra-chromosomal elements. [ABSTRACT FROM AUTHOR]

We designed and constructed three dimensional (3D) zinc oxide Nanotetrapods (T-ZnOs) modified AlGaAs/GaAs high electron mobility transistors (HEMTs) for enzymatic uric acid (UA) detection. The chemical vapor deposition synthesized T-ZnOs was distributed on the gate areas of HEMTs in order to immobilize uricase and improve the sensitivity of the HEMTs. Combining with the high efficiency of enzyme immobilization by T-ZnOs and high sensitivity from HEMT, the asconstructed uricase/T-ZnOs/HEMTs biosensor showed fast response towards UA at ~1 s, wide linear range from 0.2nM to 0.2mM and the low detect limit at 0.2 nM. The results point out an avenue to design electronic device as miniaturized lab-on-chip device for high sensitive and specific in biomedical and clinical diagnosis applications. [ABSTRACT FROM AUTHOR]

In order to construct a class of new braided crossed G-categories with nontriv- ial associativity and unit constraints, we study the G-graded monoidal category over a family of algebras {Hα}α∊G and introduce the notion of a weak (co)quasi-Turaev G-(co)algebra. Then we prove that the category of (co)representations of (co)quasitriangular weak (co)quasi-Turaev π-(co)algebras is exactly a braided crossed G-category. In fact, this (co)quasitriangular structure provides a solution to a generalized quantum Yang-Baxter type equation. [ABSTRACT FROM AUTHOR]

In recent years, the vigorous development of clinical researches carried out by medical schools is inseparable from the effective participation of medical students. However, as the number and categories of clinical research projects that medical students participate in increase, medical ethics related issues gradually occur. This article sorts out the ethical issues that arose in clinical researches, in which medical students participated, analyzes the underlying causes, and proposes solutions for the above-mentioned ethical issues, aiming to provide reference for medical ethics education and research project management for medical schools. [ABSTRACT FROM AUTHOR]

Differentiating magmatic doming and low-angle normal faulting remains critical for fully understanding the thermal, mechanical and chemical evolution of continental landmasses under extension. This zircon U-Pb dating and geochemical study documents two Middle to Late Jurassic batholiths (Lüshan and Haitangshan) from the Yiwulüshan range of western Liaoning, North China Craton. They consist of a variety of lithologies including gabbro, diorite, granodiorite, monzogranite, together with microgranular magmatic enclaves (MME) and mafic dykes. Synthesizing petrologic, elemental, whole-rock Sr-Nd and zircon Hf isotopic data leads to the characterization of multiple mafic and felsic end-members and their concomitant interaction in building the magmatic dome. A subduction-related metasomatized lithospheric mantle source is fingerprinted by the gabbroic to dioritic rocks with enriched large ion lithophile elements, depleted high field strength elements and heterogeneous isotopic compositions (87Sr/86Sri = 0.70541 to 0.70577, εNd(t) = - 1.78 to - 5.54 and zircon εHf(t) = - 6.0 to 8.1). One felsic magma end-member of ancient mafic lower crustal parentage is discernable from adakitic granites with high Sr/Y and evolved isotopic composition (87Sr/86Sri = 0.70533 to 0.70792, εNd(t) = - 18.8 to - 21.7, zircon εHf(t) = - 18.5 to - 28.8), whereas another felsic magma end-member of newly underplated crustal heritage manifests itself from some monzogranites with non-adakitic elemental affinity and juvenile isotopic composition (87Sr/86Sri = 0.70429 to 0.70587, εNd(t) = - 4.47 to - 5.87, zircon εHf(t) = 4.3 to 1.3). Hybridization processes between mantle-derived mafic magma and ancient crustal-derived felsic magma result in the formation of MME-bearing granodiorites with intermediate isotopic signatures (87Sr/86Sri = 0.70491 to 0.70499, εNd(t) = - 15.3 to - 15.8, zircon εHf(t) = - 12.7 to - 17.4). Subsequent fractional crystallization of the hybridized magmas endows the differentiated monzogranites with low Sr/Y and highly evolved isotopes (87Sr/86Sri = 0.70496 to 0.70605, εNd(t) = - 16.0 to - 18.7, zircon εHf(t) = - 14.3 to - 21.5). Apart from distinguishing Middle-Late Jurassic extensional magmatic doming from Early Cretaceous detachment faulting, this complex mafic-felsic magma association encapsulates a multi-level crust/mantle interaction leading to lithospheric thinning and concomitant crustal architectural reorganization in the Yanshan belt during the Late Mesozoic. Near-synchronization of a two-stage extensional pattern in the Yanshan belt and even across NE continental Asia accords well with gravitational collapse and convective removal of lithospheric mantle within an evolved post-collisional to within-plate extensional regime. [ABSTRACT FROM AUTHOR]

Under open-flask conditions, an efficient method to assemble a series of diversely functionalized diarylketones in the presence of commercially available NBS has been developed. Yields of up to 99% have been achieved employing diarylmethanes as starting material. Based on 18O-labeled experiment, the addition of stoichiometric water eventually leads to excellent yields in all carbonylation cases. [ABSTRACT FROM AUTHOR]

Cyanothece sp. strain PCC 7822 is a unicellular, diazotrophic cyanobacterium that can produce large quantities of H2 when grown diazotrophically. This strain is also capable of genetic manipulations and can represent a good model for improving H2 production from cyanobacteria. To this end, a knockout mutation was made in the hupL gene (ΔhupL), and we determined how this would affect the amount of H2 produced. The ΔhupL mutant demonstrated virtually no nitrogenase activity or H2 production when grown under N2-fixing conditions. To ensure that this mutation only affected the hupL gene, a complementation strain was constructed readily with wild-type properties; this indicated that the original insertion was only in hupL. The mutant had no uptake hydrogenase activity but had increased bidirectional hydrogenase (Hox) activity. Western blotting and immunocytochemistry under the electron microscope indicated that the mutant had neither HupL nor NifHDK, although the nif genes were transcribed. Interestingly, biochemical analysis demonstrated that both HupL and NifH could be membrane associated. The results indicated that the nif genes were transcribed but that NifHDK was either not translated or was translated but rapidly degraded. We hypothesized that the Nif proteins were made but were unusually susceptible to O2 damage. Thus, we grew the mutant cells under anaerobic conditions and found that they grew well under N2-fixing conditions. We conclude that in unicellular diazotrophs, like Cyanothece sp. strain PCC 7822, the HupLS complex helps remove oxygen from the nitrogenase, and that this is a more important function than merely oxidizing the H2 produced by the nitrogenase. [ABSTRACT FROM AUTHOR]

We occasionally found that cestode Taenia taeniaeformis in rats favored Sporothrix schenckii infection and survival, causing protracted cutaneous lesions. In this study, we compared the pathology and cytokines profile of rats co-infected with the two pathogens and infected with S. schenckii alone to explore underlying mechanisms. In the co-infection group, there was high expression of β-glucan receptor Dectin-1 in the cutaneous lesions and no multinucleated giant cells, but in the S. schenckii infection group the opposite was observed. Cytokines profiles demonstrated an expected finding that IL-4, commonly expressed in helminth and fungus infection, is undetectable in the two infection groups. In the single fungal infection group, cytokines IFN-γ, IL-10 and IL-17 kept increasing in the first few weeks of infection to a peak which was followed by gradual decrease. This study showed that Dectin-1 and IL-17, which were believed to be the major anti-fungus mechanisms, are Th2 independent and dispensable for clearance of S. schenckii infection, suggesting that S. schenckii has a different molecular recognition pattern and evokes anti-infection mechanisms other than Dectin-1 and IL-17. [ABSTRACT FROM AUTHOR]

5.3 million American couples of reproductive age (9%) are affected by infertility, among which male factors account for up to 50% of cases, which necessitates the identification of parameters defining sperm quality, including sperm count and motility. In vitrofertilization (IVF) with or without intra cytoplasmic sperm injection (ICSI) has become the most widely used assisted reproductive technology (ART) in modern clinical practice to overcome male infertility challenges. One of the obstacles of IVF and ICSI lies in identifying and isolating the most motile and presumably healthiest sperm from semen samples that have low sperm counts (oligozoospermia) and/or low sperm motility (oligospermaesthenia). Microfluidic systems have shown potential to sort sperm with flow systems. However, the small field of view (FOV) of conventional microscopes commonly used to image sperm motion presents challenges in tracking a large number of sperm cells simultaneously. To address this challenge, we have integrated a lensless charge-coupled device (CCD) with a microfluidic chip to enable wide FOV and automatic recording as the sperm move inside a microfluidic channel. The integrated system enables the sorting and tracking of a population of sperm that have been placed in a microfluidic channel. This channel can be monitored in both horizontal and vertical configuration similar to a swim-up column method used clinically. Sperm motilities can be quantified by tracing the shadow paths for individual sperm. Moreover, as the sperm are sorted by swimming from the inlet towards the outlet of a microfluidic channel, motile sperm that reach the outlet can be extracted from the channel at the end of the process. This technology can lead to methods to evaluate each sperm individually in terms of motility response in a wide field of view, which could prove especially useful, when working with oligozoospermic or oligospermaesthenic samples, in which the most motile sperm need to be isolated from a pool of small number of sperm. [ABSTRACT FROM AUTHOR]

5-Substituted-4-thio-2'-deoxyuridine nucleosides have been chemically synthesized and studied by NMR and UV spectroscopy. The results have been analyzed and discussed in connection with the previous data. The imino proton signal and the carbon signal of the thiocarbonyl group in the 5-substituted-4-thio-2'-deoxyuridines were found to be at much lower field, offering a potential for monitoring these modified bases at the DNA level. All 4-thionucleosides have strong absorptions at around 340 nm and consequently would be useful as potential UVA-induced anticancer agents. [ABSTRACT FROM AUTHOR]

Crystalline calcium carbonate with randomly dispersed porous structure was prepared through co- crystallization with calcium peroxide and the following template elimination by a post heating treatment and washing with water. The artificial CaCO possess abundant macro-mesopores structures and high surface area. This approach may open a new general route for the preparation of crystals with high porosity and structure specialty. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Zircon U-Pb dating, whole-rock major oxide, trace element and Sr-Nd isotopic data are presented for the Late Mesozoic mafic intrusive rocks from Yiwulüshan of western Liaoning along the eastern segment of theYanshan belt, NorthChina craton, with two episodes ofmagmatism documented. Middle Jurassic hornblende-rich gabbros show enrichment of large ion lithophile elements and light REE, and prominent depletion in high field strength elements, and possess moderately enriched isotopic compositions with (87Sr/86Sr)i ranging from 0.7056 to 0.7065 and ϵNd(t) from -5.0 to -7.1. These features suggest that the gabbros were derived from an amphibole-bearing harzburgitic lithospheric mantle source metasomatized recently by slab-derived fluids. By contrast, Early Cretaceous mafic dykes are gabbroic dioritic to dioritic in composition, with comparable trace element characteristics to continental crust and depleted isotopic signatures ((87Sr/86Sr)i = 0.7048-0.7055, ϵNd(t) = 0 to -3.0). They probably originated from partial melting of a relatively fertile asthenospheric mantle in the spinel stability field, with subsequent lower crustal assimilation and fractional crystallization. These two contrasting mafic intrusive suites, together with multiple Mesozoic mafic volcanic rocks from western Liaoning, documented a localized lithospheric thinning process, mainly through prolonged hydro-weakening or melt-rock interaction and triggered by gravitational collapse, possibly within an evolved post-collisional to within-plate extensional regime. [ABSTRACT FROM AUTHOR]

The filamentous, heterocystous, nitrogen-fixing cyanobacterium Nostoc sp. strain PCC 7120 may contain, depending on growth conditions, up to two hydrogenases directly involved in hydrogen metabolism. HypC is one out of at least seven auxiliary gene products required for synthesis of a functional hydrogenase, specifically involved in the maturation of the large subunit. In this study we present a protein, CalA (Alr0946 in the genome), belonging to the transcription regulator family AbrB, which in protein-DNA assays was found to interact with the upstream region of hypC. Transcriptional investigations showed that caL4 is cotranscribed with the downstream gene a1r0947, which encodes a putative protease from the abortive infection superfamily, Abi. CaIA was shown to interact specifically not only with the upstream region of hypC but also with its own upstream region, acting as a repressor on hypC. The bidirectional hydrogenase activity was significantly downregulated when CaIA was overexpressed, demonstrating a correlation with the transcription factor, either direct or indirect. In silico studies showed that homologues to both CalA and A1r0947 are highly conserved proteins within cyanobacteria with very similar physical organizations of the corresponding structural genes. Possible functions of the cotranscribed downstream protein A1r0947 are presented. In addition, we present a three-dimensional (3D) model of the DNA binding domain of CaIA and putative DNA binding mechanisms are discussed. [ABSTRACT FROM AUTHOR]

The Xiaofangshen mafic stock is a hornblende gabbroic body emplaced in the Faku dome of northern Liaoning within the continental interior of the North China-Mongolian plate. Zircon U-Pb SHRIMP dating yields an emplacement age of 241 ± 6 Ma. These gabbroic rocks exhibit strong enrichment in large ion lithophile elements (e.g. Th, U) and light REE, slightly negative Eu anomalies, and pronounced depletion in high field strength elements (e.g. Nb, Ta, Zr, Ti). They show a relatively narrow range of isotopic compositions with initial 87Sr/86Sr ratios of 0.7053 to 0.7055, ϵNd(t) values of +0.40 to +0.68 and zircon ϵHf(T) values from +5.0 to +7.4. These geochemical features suggest that they might have been derived from partial melting of a subduction-related metasomatized lithospheric mantle source, which is tectonically affiliated to the Xing-Meng orogenic belt. Combined with our previous geochronological dating on the predominantly granitic intrusions from the Faku dome, it is inferred that the northern Liaoning block has a tectonic affinity with the Phanerozoic accretionary orogenic belt. This revelation further leads to the proposition that the Chifeng-Kaiyuan fault likely represents the Mesozoic lithospheric boundary between the North China craton and the Xing-Meng orogenic belt in northern Liaoning. The Xiaofangshen gabbros, together with the Triassic mafic-ultramafic cumulates and granulite xenoliths and the Triassic alkaline intrusions within the continental interior of the newly amalgamated North China--Mongolian Plate, constitute an important post-orogenic to within-plate anorogenic magmatic province, in response to the continued magmatic underplating caused by lithospheric delamination and hot asthenosphere upwelling. [ABSTRACT FROM AUTHOR]

Von Willebrand factor (VWF) is secreted as ultralarge multimers that are cleaved in the A2 domain by the metalloprotease ADAMTS13 to give smaller multimers. Cleaved VWF is activated by hydrodynamic forces found in arteriolar bleeding to promote hemostasis, whereas uncleaved VWF is activated at lower, physiologic shear stresses and causes thrombosis. Single-molecule experiments demonstrate that elongational forces in the range experienced by VWF in the vasculature unfold the A2 domain, and only the unfolded A2 domain is cleaved by ADAMTS13. In shear flow, tensile force on a VWF multimer increases with the square of multimer length and is highest at the middle, providing an efficient mechanism for homeostatic regulation of VWF size distribution by force-induced A2. unfolding and cleavage by ADAMTS13, as well as providing a counterbalance for VWF-mediated platelet aggregation. [ABSTRACT FROM AUTHOR]

Abstract  Most disease resistance genes in plants encode NBS-LRR proteins. However, in woody species, little is known about the evolutionary history of these genes. Here, we identified 459 and 330 respective NBS-LRRs in grapevine and poplar genomes. We subsequently investigated protein motif composition, phylogenetic relationships and physical locations. We found significant excesses of recent duplications in perennial species, compared with those of annuals, represented by rice and Arabidopsis. Consequently, we observed higher nucleotide identity among paralogs and a higher percentage of NBS-encoding genes positioned in numerous clusters in the grapevine and poplar. These results suggested that recent tandem duplication played a major role in NBS-encoding gene expansion in perennial species. These duplication events, together with a higher probability of recombination revealed in this study, could compensate for the longer generation time in woody perennial species e.g. duplication and recombination could serve to generate novel resistance specificities. In addition, we observed extensive species-specific expansion in TIR-NBS-encoding genes. Non-TIR-NBS-encoding genes were poly- or paraphyletic, i.e. genes from three or more plant species were nested in different clades, suggesting different evolutionary patterns between these two gene types. [ABSTRACT FROM AUTHOR]

The article focuses on a study which described the use of atomic force microscopy (AFM) in showing force and compliance measurements on living cells. Specifically, the technique was used in studies of cell adhesion and cell compliance. It made use of the interaction between leukocyte function associated antigen-1/intracellular adhesion molecule-1 as a model system. Force measurements obtained provided insight about the mechanism of cell adhesion.