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Histidine-rich glycoprotein (HRG) is an abundant plasma protein harboring at least three N-glycosylation sites. HRG integrates many biological processes, such as coagulation, antiangiogenic activity, and pathogen clearance. Importantly, HRG is known to exhibit five genetic variants with minor allele frequencies of more than 10%. Among them, Pro204Ser can induce a fourth N-glycosylation site (Asn202). Considerable efforts have been made to reveal the biological function of HRG, whereas data on HRG glycosylation are scarcer. To close this knowledge gap, we used C18-based LC-MS/MS to study the glycosylation characteristics of six HRG samples from different sources. We used endogenous HRG purified from human plasma and compared its glycosylation to that of the recombinant HRG produced in Chinese hamster ovary cells or human embryonic kidney 293 cells, targeting distinct genotypic isoforms. In endogenous plasma HRG, every N-glycosylation site was occupied predominantly with a sialylated diantennary complex-type glycan. In contrast, in the recombinant HRGs, all glycans showed different antennarities, sialylation, and core fucosylation, as well as the presence of oligomannose glycans, LacdiNAcs, and antennary fucosylation. Furthermore, we observed two previously unreported O-glycosylation sites in HRG on residues Thr273 and Thr274. These sites together showed more than 90% glycan occupancy in all HRG samples studied. To investigate the potential relevance of HRG glycosylation, we assessed the plasmin-induced cleavage of HRG under various conditions. These analyses revealed that the sialylation of the N- and O-glycans as well as the genotypedependent N-glycosylation significantly influenced the kinetics and specificity of plasmin-induced cleavage of HRG. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the effects of 2 endoscopic spine surgeries on the biomechanical properties of normal and osteoporotic spines. Methods: Based on computed tomography images of a healthy adult volunteer, 6 finite element models were created. After validating the normal intact model, a concentrated force of 400 N and a moment of 7.5 Nm were exerted on the upper surface of L3 to simulate 6 physiological activities of the spine. Five types of indices were used to assess the biomechanical properties of the 6 models, range of motion (ROM), maximum displacement value, intervertebral disc stress, maximum stress value, and articular protrusion stress, and by combining them with finite element stress cloud. Results: In normal and osteoporotic spines, there was no meaningful change in ROM or disc stress in the 2 surgical models for the 6 motion states. Model N1 (osteoporotic percutaneous transforaminal endoscopic discectomy model) showed a decrease in maximum displacement value of 20.28% in right lateral bending. Model M2 (unilateral biportal endoscopic model) increased maximum displacement values of 16.88% and 17.82% during left and right lateral bending, respectively. The maximum stress value of L4-5 increased by 11.72% for model M2 during left rotation. In addition, using the same surgical approach, ROM, maximum displacement values, disc stress, and maximum stress values were more significant in the osteoporotic model than in the normal model. Conclusion: In both normal and osteoporotic spines, both surgical approaches were less disruptive to the physiologic structure of the spine. Furthermore, using the same endoscopic spine surgery, normal spine biomechanical properties are superior to osteoporotic spines. [ABSTRACT FROM AUTHOR]

Endiandra macrocarpa, a new species of Endiandra (Lauraceae) from Yunnan Province of south-western China, is here described and illustrated, based on morphological evidence. Compared to other Endiandra species occurring in south China and the adjacent regions in Indochina, this species is mainly characterised by its much larger ellipsoidal fruits (up to 11 × 6 cm), as well as glabrous branchlets and puberulent inflorescences. [ABSTRACT FROM AUTHOR]

In the present study, we designed and fabricated pH-sensitive polymeric micelles based on the conjugate of poly(2-ethyl- 2-oxazoline)-poly(D,L-lactide) (PEOz-PLA) with doxorubicin (PEOz-PLA-imi-DOX) to efficiently inhibit tumor cell growth. Hence, PEOz-PLA-imi-DOX was successfully synthesized by connecting DOX to the hydrophobic end of pH-sensitive PEOz-PLA via acid cleavable benzoic imine linker and characterized by 1H NMR spectrum and thin layer chromatography. The critical micelle concentration of PEOz-PLA-imi-DOX was determined to be (14.84±3.85) mg/L. The conjugate micelles (denoted as PP-DOX-PM) formed by PEOz-PLA-imi-DOX using film-hydration method were characterized to have a nano-scaled size of about 21 nm in diameter, and the drug loading content was 1.67%. PP-DOX-PM showed pH-dependent drug release behavior with gradually accelerated release of DOX with decrease of pH value, illustrating the micelles' distinguishing feature of endo/lysosomal pH from physiological pH by accelerating drug release. As anticipated, PP-DOX-PM maintained the cytotoxicity of DOX against MDA-MB-231 cells. Collectively, PP-DOX-PM might have great potential for effective suppression of tumor growth. [ABSTRACT FROM AUTHOR]

Objective: The impact of forage feeding strategy on growth performance, ruminal fermentation and nutrient digestibility in post-weaning calves was investigated. Methods: Forty-five female Holstein calves (body weight [BW] = 79.79±0.38 kg) were enrolled in the 35-d study at one week after weaning and randomly assigned to one of three dietary treatments. All diets were fed as total mixed ration containing 60% (dry matter [DM] basis) of basal starter feed and 40% (DM basis) of forage, but varied in composition of forage source including i) alfalfa (40% DM, AH); ii) alfalfa hay (26.7% DM)+oat hay (13.3% DM; OH); iii) alfalfa hay (26.7% DM)+corn silage (13.3% DM; WS). Results: Dry matter intake was not different among treatment groups (p>0.05). However, BW (p<0.05) and average daily gain (p<0.05) of calves fed AH and OH were greater than WS-fed calves, whereas heart girth was greater in OH-fed calves than those fed AH and WS (p<0.05). Ruminal fermentation parameters including proportion of butyric acid, acetated-to-propionate ratio, concentration of total volatile fatty acid, protozoal protein, bacterial protein, and microbial protein in rumen were the highest in OH (p<0.05) and the lowest in WS. Compared with the AH and WS, feeding oat hay to postweaning calves increased crude protein digestibility (p<0.05), and decreased duration of diarrhea (p<0.05) and fecal index (p<0.05). Conclusion: Our results suggested that partially replacing alfalfa hay with oat hay improved ruminal fermentation, nitrogen utilization, and reduced incidence of diarrhea in post-weaning dairy calves. [ABSTRACT FROM AUTHOR]

Prevalent mutations in the mitogen-activated protein kinase 1 (MAPK1)/extracellular signal-regulated kinase 2 (ERK2) pathway have been identified in cervical squamous cell carcinoma in a large-scale genome sequencing effort. Furthermore, mutations in the rat sarcoma viral oncogene homolog (RAS)/Raf/Mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathway have also been revealed to have important roles in the pathogenesis of human cancer. However, whether the potential hotspot mutations in ERK2 and other components of the RAS/RAF/MEK/ERK signaling pathway also exist in Chinese patients with cervical carcinoma remains to be elucidated. In the present study, a total of 260 patients with cervical carcinoma of distinct subtypes were analyzed for the presence of potential hotspot mutations in the RAS/RAF/MEK/ERK signaling pathway. No ERK2 mutations were detected in these samples; however, Kirsten RAS (KRAS) p.G12D (c.35G>A) mutation was identified in 2/26 (7.7%) cervical adenocarcinoma cases, including 1/20 cervical mucinous adenocarcinoma and 1/6 cervical endometrioid carcinoma cases. In addition, no mutations in the ERK1, neuroblastoma RAS, Harvey RAS or B-Raf proto-oncogene serine/threonine kinase genes were detected in the present study. These results indicated that ethnic differences may be a primary reason for the discrepancy in ERK2 mutation frequencies between the current study and previous studies. Furthermore, mutation in the KRAS gene, but not other genes in the RAS/RAF/MEK/ERK signaling pathway, may have an active role in the pathogenesis of cervical carcinoma. [ABSTRACT FROM AUTHOR]

The effect of starch infusion on production, metabolic parameters and relative mRNA abundance was investigated in low yield lactating cows from 86 days in milk. Six Holstein cows fitted with permanent ruminal cannulas were arranged into one of two complete 3×3 Latin squares and infused with a starch solution containing 800 grams starch for 16 days. The three treatments were: i) ruminal and abomasal infusion with water (Control); ii) ruminal infusion with cornstarch solution and abomasal infusion with water (Rumen); iii) ruminal infusion with water and abomasal infusion with cornstarch solution (Abomasum). There were no significant differences (p>0.05) among the three treatments with low yield lactating cows in feed and energy intake, milk yield and composition, plasma metabolism, or even on gene expression. However, cows receiving starch through rumen performed better than directly through the abomasum during the glucose tolerance test procedure with a higher area under the curve (AUC; p = 0.08) and shorter half-time (t1/2; p = 0.11) of plasma insulin, therefore, it increased glucose disposal, which stated a lipid anabolism other than mobilization after energy supplementation. In conclusion, extra starch infusion at concentration of 800 g/d did not enhance energy supplies to the mammary gland and improve the lactating performance in low yield lactating cows. [ABSTRACT FROM AUTHOR]

A highly efficient and feasible "condensation followed by annulation" synthetic approach was developed to afford a subset of 9-ring-fused quinacridone derivatives on a 10 g scale. Despite the amenable intermolecular hydrogen-bonding ability of these rigid molecules, good solubility in common organic solvents and solution processability into uniformed thin films were achieved. Integrated advantages in the synthesis and properties make these compounds ideal building blocks for high-performance dyes and optoelectronic materials. [ABSTRACT FROM AUTHOR]

Cancer is caused by multiple genetic alterations within cells. Recently, large-scale sequencing has identified frequent ribonuclease type III (DICER1), CCCTC-binding factor (CTCF), ribosomal protein L22 (RPL22), DNA (cytosine-5-)-methyltransferase 3α (DNMT3A), transformation/transcription domain-associated protein (TRRAP), isocitrate dehydrogenase (IDH)1 and IDH2 hotspot mutations in diverse types of cancer. However, it remains largely unknown whether these mutations also exist in ovarian carcinomas. In the present study, a collection of 251 patients with distinct subtypes of ovarian carcinomas were recruited and sequenced for the presence of these hotspot mutations. However, no mutations in the seven genes were detected in the samples. These negative results, together with certain recent reports, indicate that the hotspot mutations in the CTCF, RPL22, DNMT3A, TRRAP, IDH1 and IDH2 genes may not be actively involved in the carcinogenesis of ovarian carcinoma. Of note, the DICER1 mutation frequency in Sertoli-Leydig cell tumor in the present study was significantly lower compared to prior observation, and therefore, it is speculated that this discrepancy may be mainly due to the small sample size analyzed in the study. In addition, among these samples, frequent polymerase (DNA directed) ε, catalytic subunit (POLE1) and ring finger protein 43 (RNF43) mutations were identified in endometrioid and mucinous ovarian carcinomas, respectively; thus DICER1, CTCF, RPL22, DNMT3A, TRRAP, IDH1 and IDH2 hotspot mutations may not play synergistic roles with POLE1 or RNF43 mutations in the carcinogenesis of endometrioid or mucinous ovarian carcinomas. [ABSTRACT FROM AUTHOR]

The experimental study introduces an unload-induced direct-shear model to investigate the frictional slip of a layer of simulated granular gouges induced by the combination of a decreasing normal stress and a constant shear stress. A frictional equilibrium state of the gouge layer is initially established under fixed normal and shear stresses. The normal stress is proposed to decrease at a constant unloading rate to induce the frictional slip of the gouge layer, and the shear stress is proposed to keep a constant value during the test. A displacement meter and load cells synchronously measure the slip displacement and the applied normal and shear stresses, respectively. The normal and shear stresses sharply decrease with the frictional slip, owing to damage of gouge contacts. The frictional slip is then gradually arrested with new formation of gouge contacts. A greater initial shear stress induces larger normal and shear stress reductions and a smaller slip displacement. The strain energy stored in the discontinuous system before the frictional slip is found to affect the slip displacement. The advantages and the limitations of this model are discussed at the end. [ABSTRACT FROM AUTHOR]

The SM-MSR (small modular molten salt reactor) has a good prospect for development with regards to combining the superiority of the molten salt reactor and modularization technologies, showing the advantages of safety, reliability, low economic cost and flexibility of site selection. However, because its internal structural parts are not easily replaced, and the outer shielding structure is limited, the lifespan of the reactor vessel and its in-reactor shielding design needs to be addressed. In order to find an optimal shielding model with both high fuel efficiency and strong radiation shielding capability, five different design schemes were proposed in this work, which varied in thickness and boron concentration in inner-shielding materials. The neutron/gamma flux and DPA (displacements per atom)/helium production rates were evaluated to obtain an appropriate scheme. Several beneficial results were obtained. Considering the above factors and the actual manufacturing process, 20 cm-thick boron graphite with a 5 wt% Boron-10 concentration combined with a 1 cm-thick Hastelloy barrel was chosen as the in-reactor shielding structure. Outside the reactor, the neutron flux was reduced to 8.33x1010 cm-2 s-1 and the gamma flux was decreased to 1.13 x1011 cm-2 s-1. The vessel/barrel material could maintain a lifespan of more than 10 years, while the burnup depth was 6.25% lower than that of a model without inner-shielding. The conclusions of this research can provide important references for the shielding design and parameter selections of small molten salt reactors in the future. [ABSTRACT FROM AUTHOR]

The LCL resonant inductive power transfer (IPT) system is increasingly used because of its harmonic filtering capabilities, high efficiency at light load, and unity power factor feature. However, the modeling and controller design of this system become extremely difficult because of parameter uncertainty, high-order property, and switching nonlinear property. This paper proposes a frequency and load uncertainty modeling method for the LCL resonant IPT system. By using the linear fractional transformation method, we detach the uncertain part from the system model. A robust control structure with weighting functions is introduced, and a control method using structured singular values is used to enhance the system performance of perturbation rejection and reference tracking. Analysis of the controller performance is provided. The simulation and experimental results verify the robust control method and analysis results. The control method not only guarantees system stability but also improves performance under perturbation. [ABSTRACT FROM AUTHOR]

An analytic method, namely the homotopy analysis method, is applied to nonlinear problems with discontinuity governed by the differential-difference equation. Purely analytic solutions are given for nonlinear problems with discontinuity with a global convergence. This method provides a new analytical approach to solve nonlinear problems with discontinuity. Comparisons are made between the results of the proposed method and the exact solutions. The results reveal that the proposed method is very effective and convenient. [ABSTRACT FROM AUTHOR]

We investigate the violation of two types of Leggett-Garg (LG) inequalities in self-assembled quantum dots under the stationarity assumption. By comparing the two types of LG inequalities, we find the better one that is easier to be tested in an experiment. In addition, we show that the fine-structure splitting, background noise and temperature of quantum dots greatly affect the violation of LG inequalities. [ABSTRACT FROM AUTHOR]

The bacterial diversity in sediments from the northern Bering Sea was investigated by culture-independent approaches. Community fingerprint analysis by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) revealed that sediment at two deep stations (DBSE and DBS1, >400 m in depth) harbored a bacterial community distinct from the sediments collected at shallow stations (<150 m in depth) on the continental shelf. Three 16S rRNA gene clone libraries for sediments collected from shallow to deep water stations (NEC5, DBSE and DBS1, respectively) were established. Sediment collected at the deepest station DBS1 showed the highest diversity index value. Sequences fell into 19 major lineages of the domain Bacteria: Alpha-, Beta-, Gamma-, Delta- and Epsilonproteobacteria, Bacteroidetes, Acidobacteria, Actinobacteria, Firmicutes, Planctomycetes, Nitrospirae, Verrucomicrobia, Chloroflexi, Chlorobi, Spirochaetes, Cyanobacteria (or chloroplasts), and candidate divisions OP8, TM6, and WS3. A small fraction of retrieved sequences (1.8%) did not fall into any taxonomic division. Deltaproteobacteria (30%) was the dominant phylum in the three libraries, followed by Gammaproteobacteria (21%) and Acidobacteria (16%). The percentages of cloned sequences with the highest similarity to reported sequences below 97 and 93% were 48.1 and 24.3%, respectively. A large number of phylotypes affiliated with bacteria that play important roles in the carbon, sulfur, and nitrogen cycles suggest an important link of bacteria to the matter cycling in these subarctic sediments. [ABSTRACT FROM AUTHOR]

Ligand L (HL = Glycylglycine, N-[1-(2-hydroxy,5-bromophenyl)propylidene]) has been prepared which contain flexible dipeptide group and substituted phenol group. The ligand react with Cu(NO) to give the metallo-ligand [CuL], in which L acting as quadridentate ONNO chelate, coordinate to Cu(II) ion. The metallo-ligand [CuL] is rigid and has multifunctional groups. Reaction of metallo-ligand with Sr(NO) leads to the formation of the title complexes [Sr(HO)(CuL)]· (CuL)·2.25HO ( 1). This heteronuclear compound has been characterized by elemental analyses, spectroscopic analyses, and single crystal diffraction. Structural analyses reveal that the complex was crystallized in triclinic space group P-1 and has intricate 2D net-structure, which contain an infinite 1D [Sr(HO)(CuL)] ladder-like structure. In addition ESR (electron spin resonance) property and thermogravimetric analysis of 1 are discussed in detail. [ABSTRACT FROM AUTHOR]

Electron beam lithography (EBL) was used to directly pattern periodic gold nanodot arrays on optical fiber tips. Localized surface plasmon resonance of the E-beam patterned gold nanodot arrays on optical fiber tips was utilized for biochemical sensing. The advantage of the optical fiber based localized surface plasmon resonance (LSPR) sensors is the convenience to work with and work in harsh environments. An optical fiber tip LSPR refractive index sensor of 196 nm per refractive index unit (RIU) sensitivity has been demonstrated. The affinity sensing property of the fiber tip sensor was demonstrated using biotin/streptavidin as the receptor/analyte. The detection limit for streptavidin was determined to be 6 pM. [ABSTRACT FROM AUTHOR]

We demonstrate induced orientational transition of liquid crystal (LC) E7 between two optical fibre tips in a gravitational field as a result of minimising the free energy. The LC orientational transition is from a homeotropic state, with respect to fibre tip, to a tilted state as the spacing between two fibre tips is increased. The orientational distortion introduces birefringence in the optical fibre that changes the polarised direction of the output light. At short spacing, the undistorted homeotropic orientation of LC is preferred. However, at longer spacing, a distorted orientation is preferred. Once the LC director profile is known, a Finite Difference Time Domain method is used to calculate the optical properties, which agree well with the experimental results. [ABSTRACT FROM AUTHOR]

Hemorrhagic fever with renal syndrome (HFRS) is a serious public health problem in the People's Republic of China. Although 7 sero/genotypes of hantaviruses have been found in rodents, only Hantaan virus (carried by Apodemus agrarius mice) and Seoul virus (carried by Rattus norvegicus rats) reportedly cause disease in humans. During 1950-2007, a total of 1,557,622 cases of HFRS in humans and 46,427 deaths (3%) were reported in China. HFRS has been reported in 29 of 31 provinces in China. After implementation of comprehensive preventive measures, including vaccination, in the past decade in China, incidence of HFRS has dramatically decreased; only 11,248 HFRS cases were reported in 2007. Mortality rates also declined from the highest level of 14.2% in 1969 to ≈1% during 1995-2007. However, the numbers of HFRS cases and deaths in China remain the highest in the world. [ABSTRACT FROM AUTHOR]

The components and structures of ionic liquid ChCl−ZnCl2in different ChCl:ZnCl2ratios were investigated using XAFS (X-ray absorption fine structure) technique. The average coordination number and distance of Zn species at different x(ZnCl2) (mole fraction of ZnCl2when synthesizing) were calculated. It is shown that x(ZnCl2) has a regular influence on the coordination number of Zn species, due to the change of anion forms and structures in the ChCl−ZnCl2ionic liquid. The possible forms and structures of Zn species in the ionic liquids were analyzed according to the coordination number. XAFS and DSC (differential scanning calorimetry) analysis imply that besides ZnCl3−and Zn2Cl5−anions, the Cl−Zn−Cl ion pair is a main species in the ionic liquid at higher x(ZnCl2). This newly discovered Zn species has substantial influence on the properties of the ionic liquid. From the analysis of the coordination numbers and coordination distance, a new mechanism of interactions between Ch+cation and Cl−Zn−Cl ion pairs or Cl−is proposed. [ABSTRACT FROM AUTHOR]

Our interest in the phase behavior of asymmetric, industrial organic fluids focuses on understanding the impact of phase behavior, particularly solid phase behavior, on flow assurance and other reservoir fluid management and production issues, as well as on heavy oil partitioning processes in upgrading operations. Recent developments in X-ray view cell technology allow us to examine the phase behavior of fluids containing large mass fractions of asphaltenes, and dispersed organic and inorganic solids, in a routine manner. Over the past three years we have been preparing detailed phase behavior maps, including phase densities, for the model system Athabasca Bitumen Vacuum Bottoms (ABVB), a 525+ °C fraction containing 32 wt% pentane asphaltenes + pentane, heptane and dodecane using a variable volume X-ray view-cell. The X-ray view-cell experimental program focused on the temperature range, 100 to 340°C, and the pressure range, 0.1 to 30 MPa. The mixtures exhibit complex but reversible multiphase behaviors. Over much of the phase space solids, if present, remain dispersed. Over a narrow range of conditions the solids tend to settle. In addition, adherent deposits, including solids and viscous liquids, are observed at temperatures less than 200°C over a broad range of conditions. [ABSTRACT FROM AUTHOR]

The correlation and prediction of deposit formation are at the core of flow assurance, risk assessment, and other reservoir fluid management issues and are equally important for heavy oil or bitumen partitioning and upgrading. Asphaltene deposition in particular is a key topic in both sectors. Hydrocarbons from condensate-rich reservoir fluids to bitumen + diluent mixtures share constituents, from asphaltenes and resins to pentane, and can all be classified as asymmetric from a phase behavior perspective. The phase dia-grams for these asymmetric fluids are characterized by zone of four-phase behavior surrounded by three-phase and two-phase regions in both pressure-composition at constant temperature, and pressure–temperature at constant composition diagrams. Adherent asphaltenic solid and liquid deposits only arise within some multiphase zones. Zones such as the SL1, SL1V, L1L2V, and L1L2 are prone to the production of adherent asphaltenic deposits particularly when combined with intermittent or laminar flow. By incorporating incomplete approaches prevalent in both sectors into qualitative four component phase diagrams, one can illustrate key aspects of the phase diagrams for the entire range of fluids, as well as the challenges faced with respect to the prediction of specific phase behaviors. In this article we present and illustrate some of these challenges and propose a path toward their resolution. [ABSTRACT FROM AUTHOR]

We report a case of Babesia microti infection in an immunocompetent child <5 years of age that caused fever and severe intravascular hemolysis. Physicians in China should be aware of babesiosis, especially in the differential diagnosis of immune hemolytic anemia with negative results for antiglobulin tests. [ABSTRACT FROM AUTHOR]

Objectives: Endometriosis is a common gynecological disease affecting up to ~10% of women at reproductive age. Prior combined studies implied that MARVELD2 might be involved in the pathogenesis of certain malignancies. Here, 211 Han Chinese samples with ovarian endometriosis were analyzed for the presence of MARVELD2 mutations. Methods: We analyze the potential presence of MARVELD2 mutations by direct DNA sequencing. Results: A total of 7 variants, 5 missense and 2 synonymous variants, were identified in our 211 ovarian endometriosis samples with different frequencies. Among the 5 missense variant, a missense rare variant p.V198M (c.592G>A), was identified in 10 out of our 211 samples (4.74%). This rare variant was identified with extremely low frequency in 766 control samples from 766 Chinese women without endometriosis (0.13%, 1/766) and control samples in the public databases. The evolutionary conservation analysis results suggested that the MARVELD2 rare variant lead to highly conserved amino acid substitutions among 14 vertebrate species from Human to Snake. Furthermore, both the SIFT and Polyphen-2 programs predicted this rare variant to be 'disease causing'. However, we failed to observe any statistical significance between the MARVELD2 rare variant and the available clinical data. Conclusions: We identified a potential pathogenic rare variant in the MARVELD2 gene in Chinese samples with ovarian endometriosis, indicating the MARVELD2 rare variant might play an active role in the pathogenesis of endometriosis. [ABSTRACT FROM AUTHOR]

A metal—organic polyhedron of truncated octahedral geometry augmented with a C4-symmetric square-planar CuII paddle-wheel node as a secondary building unit can be prepared using a C3-symmetric ligand that occupies the face of the octahedral cage, where the three phenyl groups containing a m-carboxylate group in the ligand provide the necessary curvature to form the finite octahedral cage. [ABSTRACT FROM AUTHOR]

A C3 symmetric ligand with three 1,3-benzenedicarboxylate units has been used to construct a metal–organic framework with a (3,24)-connected network topology, where the nanometre-sized metal–organic cuboctahedra (MOCs) have been incorporated solely into a cubic close packing (CCP) arrangement, which led to superoctahedral and supertetrahedral cavities. [ABSTRACT FROM AUTHOR]

An interdigitated 3-D metal–organic framework, [Cd3(OH)2L4(H2O)2], with 1-D channels was prepared using 4-aminophenyl-1H-tetrazole (HL) and Cd(ii) ions, where the host framework shows selective gas sorption behavior that is based on the different nature of the interactions between the gas and the framework rather than on the size-exclusion effect of the micropores. [ABSTRACT FROM AUTHOR]

An unprecedented twofold interpenetrating (3,4)-connected topology of the Cu3L4-type metal–organic framework was prepared using N,N′,N″-tris(4-pyridinyl)-1,3,5-benzenetricarboxamide (L) as a trigonal three-connection node and the copper(ii) ion as a square planar four-connection node, where the framework contains remarkably large 1-D solvent channels. [ABSTRACT FROM AUTHOR]

Introduction: Tuberculosis (TB) is one of the top ten causes of death in the world. The purpose of this study was to explore the relationship between the short-term exposure to air pollutants and the risk of pulmonary TB in Chongqing. Methodology: A distributed lag nonlinear model was used to explore the effect of short-term exposure to air pollutants on the risk of pulmonary TB. Stratified analysis was used to explore the impact of gender and age on the risk of pulmonary TB. Results: There were 170,934 confirmed cases of pulmonary TB in Chongqing from January 1st, 2014 to December 30th, 2020. There was a positive correlation between the exposure to particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5), particulate matter with aerodynamic diameter less than 10 µm (PM10) ozone (O3) and the incidence risk of TB. The maximum lag-specific relative risk (RR) of pulmonary TB was 1.012 (95% CI: 1.001-1.023, 14 days delay) for each 10 µg/m¹ increase in PM2.5; 1.010 (95% CI: 1.003-1.017, 14 days delay) for each 10µg/m¹ increase in PM10; and 1.002 (95% CI:1.000-1.004, 2 days delay) for each 10 mg/m¹ increase in O3. Stratified analysis showed that the exposure effects of PM2.5, PM10 and O3 were different between different genders and age. Conclusions: This study suggested that exposure to PM2.5, PM10, and O3 was associated with the risk of pulmonary TB, and the risk was higher for males than females, while the exposure to PM2.5 and PM10 was riskier for people aged 15-60 years. [ABSTRACT FROM AUTHOR]

Introduction: Controlled ovarian hyperstimulation (COH) is essential for artificial reproduction technology (ART). This study aimed to evaluate the effects of a mild starting dosage of r-FSH ovarian stimulation after the modified prolonged GnRH-a down-regulation protocol for COH on the clinical outcomes in normal ovarian responders undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET).Material and Methods: In the retrospective study, the patients were separated into two groups according to the starting dosage of r-FSH: a mild dosage group (75 IU ≤ r-FSH < 150 IU, n = 858) and a conventional dosage group (150 IU ≤ r-FSH ≤ 225 IU, n = 535). Data were collected from clinical records. The baseline characteristics and clinical outcomes were compared between the two groups.Results: Although the duration of r-FSH treatment was a little longer in the mild dosage group, the total r-FSH dosage and the cost of ovarian stimulation were significantly lower than those in the conventional dosage group. Furthermore, compared to the conventional dosage group, the number of retrieved oocytes was also lower in the mild dosage group, whereas the rates of two pronuclei (2PN) fertilized oocytes and good-quality embryos were remarkable higher. The implantation rate, clinical pregnancy rate and live birth rate were significantly higher in the mild dosage group. There was no difference in early miscarriages rate, incidence of moderate and severe ovarian hyper-stimulation syndrome (OHSS) or incidence of ectopic pregnancy between the two groups.Conclusions: The modified prolonged GnRH-a pituitary down-regulation regimen combined with mild r-FSH starting dosage improved IVF/ICSI outcomes and reduced the financial cost in normal ovarian responders. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to evaluate whether flow-mediated dilation (FMD) can be used to predict incident hypertension in patients with hyperuricemia.Material and Methods: Normotensive participants with and without hyperuricemia at baseline were prospectively enrolled. Flow-mediated dilation was assessed at baseline, and after 1 year's follow-up the incidence of hypertension was compared between those with and without hyperuricemia. The predictive value of baseline FMD for incident hypertension among hyperuricemia patients was evaluated.Results: A total of 222 participants were included. Mean systolic and diastolic blood pressure (BP) was 129.5 ±8.4 mm Hg and 78.3 ±7.9 mm Hg. Mean serum uric acid (UA) level was 4.4 ±2.8 mg/dl. Mean FMD was 5.1 ±2.7%. Compared to normal UA group, hyperuricemia group had higher proportion of male (58.4% vs. 61.2%), higher systolic BP (125.4 ±7.9 mm Hg vs. 132.1 ±7.3 mm Hg), serum high sensitivity C-reactive protein (3.9 ±2.2 mg/dl vs. 4.5 ±3.0 mg/dl) and UA (3.5 ±1.4 mg/dl vs. 5.7 ±0.7 mg/dl) levels, but lower mean FMD (5.6 ±2.4% vs. 4.8 ±2.0%) (p < 0.05 for all comparisons). No participant in normal UA group developed hypertension, while in hyperuricemia group, 6 participants developed hypertension. In hyperuricemia participants, after adjusted for covariates, per 1-standard deviation decrease in baseline FMD remained significantly associated with 15% increased risk of incident hypertension.Conclusions: Patients with hyperuricemia have an increased risk of developing hypertension, and low baseline FMD in hyperuricemia patients is associated with significantly increased risk of incident hypertension. [ABSTRACT FROM AUTHOR]

Aiming at achieving high robustness performance in Wireless Power Transfer (WPT) systems for moving robot power supply, this paper proposes a H¥ robust control method with multiple parameters that vary randomly, including the mutual inductance, load parameter, and operating frequency. These uncertain parameters make the system control extremely difficult. A composite Upper Linear Fractional Transformation (LFT) method is proposed to deal with the system uncertainty, particularly for the mutual inductance detachment, which is very unique and important for WPT systems. A suboptimal H¥ controller design method is proposed based on Generalized State Space Averaging (GSSA) model in order to simplify the system structure. In controller implementation, a virtual buck converter for phase shifted regulation is proposed to replace real input buck converter. The proposed H¥ control method is easy to implement because only the output voltage of the WPT system needs to be sampled, and based on which a simple DSP control algorithm is developed. Simulation and experimental results have demonstrated that the proposed control method can achieve less than 15 ms response speed with 70% mutual inductance variation and 50% load variation tolerance respectively. [ABSTRACT FROM AUTHOR]

Objective To explore the cytochrome P450 family 27 subfamily A member 1 (CYP27A1) gene mutations in Chinese women with intrahepatic cholestasis of pregnancy (ICP) and the correlation between CYP27A gene mutations and BA (bile acid) level changes. Methods In this study, the entire coding region of the CYP27A1 gene was sequenced in 151 Han Chinese women with ICP and 1029 matched samples, and the pathogenicity of identified CYP27A1 gene mutations was judged through evolutionary conservation analysis, computational analysis and protein structure modeling. Finally, we verified the relationship between gene mutations and total serum bile acid (TBA) and cholesterol (CHOL) levels through experiments in cell culture. Results We identified five heterozygous CYP27A1 missense mutations in five ICP samples. Three online tools, Polyphen-2, MutationTaster and SIFT, predicted that the five CYP27A1 mutations were pathogenic. Furthermore, all five mutations caused marked protein structural changes. Experiments in cells showed that the intracellular and medium levels of TBA in the mutant groups were lower than those in the wild-type group, while the CHOL levels were higher in all mutants except for the R158H mutant. Conclusions CYP27A1 mutations are associated with the levels of TBA and CHOL, suggesting that CYP27A1 mutations contribute to abnormal total cholesterol and BA levels, which leads to ICP. [ABSTRACT FROM AUTHOR]

The influence of a bias voltage on the surface-driven orientational transitions of liquid crystals (LCs) resulting from the weakening anchoring and anchoring transition was analysed theoretically and experimentally. The continuum theory of nematic LCs was used to model the LC deformation under different anchoring energies. A microelectroplated interdigitated Au structure was used in the nematic LC-based chemical and biological sensors. With a suitable bias electric field, the processes of the weakening anchoring energy and the uniform surface-driven orientational transition due to targeted molecules binding to a functionalized surface were observed optically. These results can be used to improve the sensitivity, response speed and signal strength of LC-based chemical and biological sensors. [ABSTRACT FROM AUTHOR]

• A new macro-track transport acceleration method with sparse macro-tracks for complex geometry is proposed. • Complex 2D geometries are modeled by Constructive Solid Geometry. • Cyclic tracking is implemented for both the Method of Characteristics and macro-track acceleration method. • Results from C5G7 2D benchmark show excellent speedup for runtime of the macro-track acceleration method. The method of characteristics is a flexible method in heterogeneous geometry and has been widespread use for reactor physics lattice calculation and whole core simulation. However, many acceleration methods commonly used in traditional lattice code and nodal method are not applicable to or inefficient to heterogeneous-geometry, high-dominance-ratio problems. This paper presents a new macro-track transport acceleration method which makes the acceleration without geometrical limitations a reality. The new macro-track transport acceleration method specially designed for the MOC does not use all the parallel tracks as macro-tracks and reduces the computational time without MOC sweeps increment. According to the parametric study, the maximum speedups of 38 relative to unaccelerated MOC transport sweeps and 16.7 relative to unaccelerated MOC runtime were achieved in the C5G7 2D problem. [ABSTRACT FROM AUTHOR]

The objectives of this study were to 1) determine the variation of nutrient digestion, plasma metabolites and oxidative stress parameters triggered by induced subacute ruminal acidosis (SARA); and 2) evaluate the ability of pelleted beet pulp (BP) as a replacement for ground corn to alleviate SARA. Eight Holstein-Friesian cows were fed four diets during four successive 17-day periods: 1) total mixed ration (TMR) containing 0% finely ground wheat (FGW) (W0); 2) TMR containing 10% FGW (W10); 3) TMR containing 20% FGW (W20); and 4) TMR containing 10% BP as a replacement for 10% ground corn (BP10). The SARA induction protocol reduced the mean ruminal pH from 6.37 to 5.94, and the minimum ruminal pH decreased from 5.99 to 5.41 from baseline to challenge period. Mean ruminal pH increased from 5.94 to 6.05, and minimum daily ruminal pH increased from 5.41 to 5.63, when BP was substituted for corn. The apparent digestibility of nutrients was not affected by the dietary treatments, except that the digestibility of neutral detergent fibre (NDF) and acid detergent fibre (ADF) was reduced in cows fed the W20 diet compared with cows fed the W0 and W10 diets, and cows fed the BP10 diet had higher NDF and ADF digestibility than the cows fed the W20 diet. Cows fed the W20 diet had a lower plasma concentration of ß-hydroxybutyrate (BHBA), non-esterified fatty acids (NEFA), cholesterol, triglyceride, and total antioxidative capacity (TAC), and a higher plasma concentration of glucose, insulin, malonaldehyde (MDA), super oxygen dehydrogenises (SOD), and glutathione peroxidase (GSH-Px) than cows fed the W0 diet. Substitution of BP for corn increased concentrations of plasma BHBA and TAC, but decreased concentrations of plasma MDA. Our results indicate that reduction of fibre digestion; the concomitant increase of plasma glucose and insulin; the decrease of plasma BHBA, NEFA, cholesterol, and triglyceride; and changes of plasma oxidative stress parameters are highly related to SARA induced by W20 diets. These variables may be alternative candidates for SARA diagnosis. We also suggest that the substitution of BP for corn could reduce the risk of SARA, increase fibre digestion, and improve the antioxidant status in dairy cows. [ABSTRACT FROM AUTHOR]

Six new neutral crystalline clusters Zn8S(SC6H5)14L2[L = pyridyl (1), 3-(phenylthio)pyridyl (2), 4-(phenylthio)pyridyl (3), 3-iodopyridyl (4), 3-butylpyridyl (5), and phenanthridyl (6)] with Zn8S cores have been assembled by a hydrothermal process. Exceptionally, in situ ligand reactions have been observed in clusters 2and 3. There are no detectable fluorescence emissions of complexes 1−5, whereas 6shows an emission peak at 365 nm due to the existence of terminal phenanthridyl ligands. [ABSTRACT FROM AUTHOR]

Microbial ecosystems have been widely used in industrial production, but the inter-relationships of organisms within them haven't been completely clarified due to complex composition and structure of natural microbial ecosystems. So it is challenging for ecologists to get deep insights on how ecosystems function and interplay with surrounding environments. But the recent progresses in synthetic biology show that construction of artificial ecosystems where relationships of species are comparatively clear could help us further uncover the meadow of those tiny societies. By using two quorum-sensing signal transduction circuits, this research designed, simulated and constructed a synthetic ecosystem where various population dynamics formed by changing environmental factors. Coherent experimental data and mathematical simulation in our study show that different antibiotics levels and initial cell densities can result in correlated population dynamics such as extinction, obligatory mutualism, facultative mutualism and commensalism. This synthetic ecosystem provides valuable information for addressing questions in ecology and may act as a chassis for construction of more complex microbial ecosystems. [ABSTRACT FROM AUTHOR]

A series of novel soluble copolymers based on fluorene monomer in conjugation with carbazole and iridium complex monomers have been synthesized by the Suzuki polycondensation reaction. Iridium complexes based on 2-phenylquinoline or 1-phenylisoquinoline were incorporated into copolymers through a -diketonate ancillary ligand. The copolymers were characterized by using 1H NMR, 13C NMR, IR, and GPC. TGA/DSC measurements indicated that the copolymers have good thermal and morphological stability. An electrochemical investigation revealed that the HOMO and LUMO energy levels of the monomeric iridium complexes fall within those of the host polymer PFCz. The absorption spectra of the copolymers were dominated by absorptions from the fluorene-alt-carbazole backbone, while their photoluminescence (PL) spectra were dominated by emissions from the iridium complexes even at a feed ratio of the complex as low as 0.5 mol %. The copolymers PFCzIrphq emit orange-red light with an emission peak at ca. 590 nm, while PFCzIrpiq emits saturated red light with an emission maximum at ca. 620 nm, with a slight red shift compared with the emissions for the corresponding monomeric iridium complexes, respectively. Light-emitting diodes using the copolymers as emission layers under three types of device configurations were fabricated. The devices with 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD) doping display external quantum efficiencies significantly higher than those without PBD. A saturated red-emitting PLED with an emission peak at 628 nm, a maximum external quantum efficiency of 0.6% at the current density (J) of 39 mA/cm2, and a maximum luminance of 541 cd/m2at 16 V was achieved from the device ITO/PEDOT/PFCzIrpiq3PBD(40%)/Ba/Al. [ABSTRACT FROM AUTHOR]

The molten chloride salt fast reactor (MCFR) with Th-U fuel cycle is attracting more and more attention because of its excellent performance, such as high solubility of actinides, superior breeding capacity, low waste production, and high inherent safety. First of all, the breeding capability of an MCFR at equilibrium state was optimized by an in-house automated optimization program. Based on an optimized MCFR, an investigation of Th-U cycle performance was performed. Due to the lack of available 233U in nature, transuranium (TRU), low-enriched uranium (LEU), and Pu were employed as the startup fissile materials, and two different transition scenarios, a breeding and burning (B&B) scenario and a pre-breeding and burning (PBB) scenario were studied. The results show that the breeding performance in an MCFR is attractive and that the Th-U fuel transition can be achieved smoothly by using LEU, Pu, or TRU as startup fissile materials. In the B&B scenario, the average net 233U production rate in the LEU-started, TRU-started, and Pu-started modes during 200-year operation is 374, 321, and 323 kg/a, respectively, at the reprocessing rate of 200 L/day. While in the PB&B scenario the average annual 233U production is about 570 kg for all startup cases at a reprocessing rate of 40 L/day, and the corresponding doubling time is about 9.6 years. Besides, the values of the fuel Doppler coefficient and density coefficient are negative, and the total temperature coefficient of reactivity in all scenarios is below −8 pcm/K. In addition, the value of radiotoxicity of the Th-U cycle in an MCFR is lower than that in other molten salt reactors like the molten-salt breeder reactor and the molten fluoride salt reactor due to the lower buildup of fission products and TRU under its hard spectrum. [ABSTRACT FROM AUTHOR]

Based on first-principles quantum-mechanical calculations, the impurity-dopant effects of phosphorus on ∑5(012) symmetrical tilt grain boundary in nickel have been studied. The calculated binding energy suggests that phosphorus has a strong tendency to segregate to the grain boundary. Phosphorus forms strong and covalent-like bonding with nickel, which is beneficial to the grain boundary cohesion. However, a too high phosphorus content can result in a thin and fragile zone in the grain boundary, due to the repulsion between phosphorus atoms. As the concentration of phosphorus increases, the strength of the grain boundary increases first and then decreases. Obviously, there exists an optimum concentration for phosphorus segregation, which is consistent with observed segregation behaviors of phosphorus in the grain boundary of nickel. This work is very helpful to understand the comprehensive effects of phosphorus. [ABSTRACT FROM AUTHOR]

Hfq is a bacterial post-transcriptional regulator. It facilitates base-pairing between sRNA and target mRNA. Hfq mediates DsrA-dependent translational activation of rpoS mRNA at low temperatures. rpoS encodes the stationary-phase σ factor σS, which is the central regulator in general stress response. However, structural information on Hfq--DsrA interaction is not yet available. Although Hfq is reported to hydrolyze ATP, the ATP-binding site is still unknown. Here, we report a ternary crystal complex structure of Escherichia coli Hfq bound to a major Hfq recognition region on DsrA (AU6A) together with ADP, and a crystal complex structure of Hfq bound to ADP. AU6A binds to the proximal and distal sides of two Hfq hexamers. ADP binds to a purine-selective site on the distal side and contacts conserved arginine or glutamine residues on the proximal side of another hexamer. This binding mode is different from previously postulated. The cooperation of two different Hfq hexamers upon nucleic acid binding in solution is verified by fluorescence polarization and solution nuclear magnetic resonance (NMR) experiments using fragments of Hfq and DsrA. Fluorescence resonance energy transfer conducted with full-length Hfq and DsrA also supports cooperation of Hfq hexamers upon DsrA binding. The implications of Hfq hexamer cooperation have been discussed. [ABSTRACT FROM AUTHOR]

A two-step extraction method was used to extract proteins from Caragana korshinskii Kom., including a NaOH solution extraction followed by a water extraction. A power-law model, three-site kinetic extraction model, and second-order model were utilized to investigate the mechanism of the water extraction process and the key factors affecting the protein yield. The experimental data fitted well with the three-site kinetic model, indicating that the water extraction process included washing and faster and slower stages. In addition, the slower stage was the rate-limiting step. For the water extraction process, the protein yield was increased by decreasing the particle size, increasing the NaOH concentration, or raising the extraction temperature, among which the extraction temperature was the critical factor for controlling the protein yield. [ABSTRACT FROM AUTHOR]

The Weibel instability, a subject of relevance to many fields of physics ranging from inertial confinement fusion to some astrophysical scenarios, is usually probed with side-on proton radiography. In order to diagnose the strength and wavelength of the spontaneous fields, two concerns that must be settled are how to distinguish the coexisting electric and magnetic fields, and how to overcome the counteracting of deflections in radiographing the filamentary structured fields. In this paper, proton radiography of the Weibel instability in two counterstreaming plasma flows is studied by simulation. It suggests that the electric field dominates the deflection of probe protons, whereas the contribution from the magnetic field is negligible. To resolve the deflectioncounteracting problem, the spatial spectrum of the electric field energy is found to be related to the deflection velocity of the probe beam by theoretical analyses. The strength and wavelength of the electric field are then obtainable from the proton flux on the detection plane, whereas the strength and wavelength of the magnetic field can be deduced through the equilibrium between the electric field and the magnetic field pressure gradient after the linear growth stage of the instability. Both numerical and experimental verifications suggest that our method performs well in extracting the strength and wavelength of the spontaneous electric and magnetic fields of the Weibel instability from proton radiography. [ABSTRACT FROM AUTHOR]

Steam explosion (SE) was used to pretreat rice straw (RS) and Caragana korshinskii Kom. (CKK). Enzymatic hydrolysis of pretreated RS and CKK, and a pure cellulose (bacterial cellulose, BC) were performed and compared. The characteristics and changes of different substrates during pretreatment and enzymatic hydrolysis were observed. After SE pretreatment, the hemicellulose content of RS and CKK was decreased from 21.7% to 4.9% and 17.9% to 6.2%, respectively. The cellulose percent of RS and CKK was increased to 45.1% and 38.4%, and the enzymatic hydrolysis conversion of cellulose was increased 1.1 times and 0.9 times, respectively. Although the composition and enzymatic yield of different substrates varied, their enzymatic hydrolysis rates showed a similar declining trend during enzymatic hydrolysis. The adsorption capacities of substrates on the enzyme were increased by pretreatment. The enzymatic hydrolysis efficiency was closely related to the enzyme adsorption capacities of substrates at the initial stage (1 h). The BC and SE pretreated RS first adsorbed and subsequently desorbed the enzyme, while the untreated RS and CKK had weak adsorption capacity and formed irreversible adsorption with the enzyme. The changes in crystallinity after enzymatic hydrolysis suggested that there was no direct correlation between the crystallinity and digestibility of cellulose. [ABSTRACT FROM AUTHOR]

A 247 mg weight coin-size piezoelectric-driven micro air vehicle (MAV) with four symmetrical distributed bionic flexible wings is presented. The MAV is planar designed and monolithic fabricated via film printed circuit, graphic lasering and lamination process, and is able to be self-assembled by using shape memory polymer (SMP). The SMP can be heated by the flexible circuit and shrink at a large strain, resulting in the self-folding of hinges and self-assembly of MAV from 2D shape into 3D shape. The flexible four-bar mechanism converts the slight vibration of lead zirconate titanate (PZT) actuator into flexible wings' reciprocation, thereby generating lift force. The response characteristics and motion behaviour of the MAV are experimentally tested. Results suggest that the prototype can be self-assembled to the designed position and achieve a 23.5° reciprocating angle at 134 Hz resonance frequency under 280 V driving signals. [ABSTRACT FROM AUTHOR]

A 165 mg coin-size bionic water-skating robot driven by piezoelectric (PZT) bending actuator is presented. The robot with light weight and elastic legs uses surface tension to keep itself on the water surface. The driving force produced by flapping wings enables it to glide easily due to tiny resistance coefficient of water surface. The robot consists of PZT bending actuator, four-bar transmission structure, two flapping wings, four elastic legs and the body. The actuator bending at resonance frequency of 105 Hz achieves 346 µm displacement at the end of actuator at voltage of 280 V so that the flapping angle of the wings reaches 73° at that frequency. Tests show that, the maximum equivalent payload of robot is 830.6 mg, about five times of its own mass, before breaking the water surface, and the water drag when robot skates on the water surface is about 29 µN, 1.76% of its gravity. The maximum forward speed of the robot is measured as 151 mm/s. [ABSTRACT FROM AUTHOR]