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Carbon nanotubes (CNTs) have high strength and stable chemical properties, offering the potential to enhance the mechanical performance of cementitious grouting materials and finding wide applications in the field. This paper reviews the recent research on the application of CNTs in cementitious grouting materials. It introduces the basic structure of CNTs and commonly used dispersion methods in cementitious grouting materials, analyzing and summarizing hydration and microstructure, mechanical properties, and early shrinkage performance of carbon nanotubes-cementitious grouting materials, highlighting current research challenges. Additionally, the future research on CNTs in cementitious grouting materials is also envisioned. [ABSTRACT FROM AUTHOR]

Purpose: The association between serum uric acid (SUA) and atrial fibrillation (AF) has been widely focused on and studied in recent years. However, the exact association between SUA and AF is unclear, and the effect of gender on the association between SUA levels and AF has been controversial. This study aimed to investigate the association between SUA levels and non-valvular AF (NVAF) and the potential effect of gender on it. Patients and Methods: A total of 866 NVAF patients (463 males, age 69.44 ± 8.07 years) and 646 sex-matched control patients in sinus rhythm, with no history of arrhythmia were included in this study. t-test, ANOVA, and chi-square test were used for baseline data analysis. The receiver operating characteristic curve, logistic regression and Pearson correlation analysis were used for correlation analysis. Results: Compared to controls, NVAF patients exhibited higher SUA (P< 0.001). After adjusting for confounders of NVAF, SUA remained significantly associated with NVAF, regardless of gender (OR= 1.31, 95% CI 1.18– 1.43, P< 0.001). SUA demonstrated higher predictability and sensitivity in predicting the occurrence of female NVAF compared to male (area under the curve was 0.68 (95% CI 0.64– 0.72, P< 0.001), sensitivity 87.3%), with the optimal cut-off point identified as 5.72 mg/dL. Furthermore, SUA levels correlated with APOA1, Scr and NT-proBNP in NVAF patients. SUA levels varied significantly among NVAF subtypes. Conclusion: High SUA levels were independently associated with NVAF, regardless of gender. SUA exhibited higher predictability and sensitivity in predicting the occurrence of NVAF in females compared to males. High SUA levels may affect other NVAF-related factors and participate in the pathophysiological process of NVAF. [ABSTRACT FROM AUTHOR]

To improve the efficiency of frozen soil excavation, the new shaft tunneling machine was developed. The new shaft tunneling machine exerts pressure on the frozen soil through the cutter under the joint action of its own gravity, the drum rotational force and the inertia force, and the frozen soil is damaged. By unique way of breaking frozen soil to improve the efficiency of frozen soil excavation, the drum rotation speed is one of the factors affecting the performance of frozen soil excavation. This article applies SolidWorks software to establish the model of cutter breaking frozen soil, takes advantage of Hyper Mesh finite element software coupled with LS-DYNA solver to acquire the regular pattern of change in the force change, frozen soil stress–strain and specific energy of cutter crushing frozen soil, etc., which analyzes the destruction of frozen soil when the drum of the new shaft tunneling machine is rotating at the speed of 25–40 rpm. Combine with field test to investigate the mechanism of cutter breaking frozen soil under the optimal drum rotation speed. The investigation results demonstrate that: when frozen soil's self-bearing capacity is lower than the force of cutter, it breaks up and detaches from the soil body, and frozen soil undergoes tensile, compressive and shear damages. For this research, it is instructive for practical engineering. [ABSTRACT FROM AUTHOR]

Background: Spontaneous bacterial peritonitis (SBP) is a common complication in patients with cirrhosis. The diagnosis of SBP is still mostly based on ascites cultures and absolute ascites polymorphonuclear (PMN) cell count, which restricts the widely application in clinical settings. This study aimed to identify reliable and easy-to-use biomarkers for both diagnosis and prognosis of cirrhotic patients with SBP. Methods: We conducted a retrospective study including 413 cirrhotic patients from March 2013 to July 2022 in the First Affiliated Hospital of Guangxi Medical University. Patients' clinical characteristics and laboratory indices were collected and analyzed. Two machine learning methods (Xgboost and LASSO algorithms) and a logistic regression analysis were adopted to screen and validate the indices associated with the risk of SBP. A predictive model was constructed and validated using the estimated area under curve (AUC). The indices related to the survival of cirrhotic patients were also analyzed. Results: A total of 413 cirrhotic patients were enrolled in the study, of whom 329 were decompensated and 84 were compensated. 52 patients complicated and patients with SBP had a poorer Child–Pugh score (P < 0.05). Patients with SBP had a greater proportion of malignancies than those without SBP(P < 0.05). The majority of laboratory test indicators differed significantly between patients with and without SBP (P < 0.05). Albumin, neutrophil-to-lymphocyte ratio (NLR), and ferritin-to-neutrophil ratio (FNR) were found to be independently associated with SBP in decompensated cirrhotic patients using LASSO algorithms, and logistic regression analysis. The model established by the three indices showed a high predictive value with an AUC of 0.808. Furthermore, increased neutrophils, ALP, and C-reactive protein-to-albumin ratio (CAR) were associated with the shorter survival time of patients with decompensated cirrhosis, and the combination of these indices showed a greater predictive value for cirrhotic patients. Conclusions: The present study identified FNR as a novel index in the diagnosis of SBP in decompensated patients with cirrhosis. A model based on neutrophils, ALP and CAR showed high performance in predicting the prognosis of patients with decompensated cirrhosis. [ABSTRACT FROM AUTHOR]

Some photosensitive resins have poor mechanical properties after 3D printing. To overcome these limitations, a polyurethane acrylate oligomer (PUA) microsphere was prepared using the Pickering emulsion template method and ultraviolet (UV) curing technology in this paper. The prepared PUA microspheres were added to PUA-1,6-hexanediol diacrylate (HDDA) photosensitive resin system for digital light processing (DLP) 3D printing technology. The preparation process of PUA microspheres was discussed based on micromorphology, and it was found that the oil-water ratio of the Pickering emulsion and the emulsification speed had a certain effect on the microsphere size. As the oil-water ratio and the emulsification speed increased, the microsphere particle size decreased to a certain extent. Adding a suitable proportion of PUA microspheres to the photosensitive resin can improve the mechanical properties and thermal stability. When the modified photosensitive resin microsphere content was 0.5%, the tensile strength, elongation at break, bending strength, and initial thermal decomposition temperature were increased by 79.14%, 47.26%, 26.69%, and 10.65%, respectively, compared with the unmodified photosensitive resin. This study provides a new way to improve the mechanical properties of photosensitive resin 3D printing. The resin materials studied in this work have potential application value in the fields of ceramic 3D printing and dental temporary replacement materials. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp) is coassembled with many organic molecular templates led by collagens in natural bone. In this study, it is presumed that small intestinal submucosa (SIS) with acetamide group chelates calcium ion and bacterial cellulose (BC) has strong intermolecular hydroxyl group and powerful attraction for calcium ion to initiate initial nucleation. Phosphate ions bind calcium ions to form seed crystal of calcium phosphate, which is further directionally grown under the mediation of the template structure and finally forms weakly crystalline HAp, providing an environment for the HAp formation. Besides, the samples are characterized by X‐ray diffraction, Fourier transform infrared, X‐ray photoelectron spectroscopy, scanning electron microscope, and transmission electron microscope to unveil the phase structure, composition, and morphology, and a growth mechanism is proposed. HAp is successfully synthesized on SIS–BC biomineralization template. The results show morphology of samples from sheet‐lamellar‐like to flower‐like or porous‐spheroid‐like from 1 day to 7 days. The plate‐like HAp rods are polycrystal with c‐axis orientation. Interestingly, the HAp/SIS‐BC composites have the least relative mass of HAp on mineralization and the content of HAp (57%) is very close to the human bone tissue in structure (about 60%). Finally, the HAp mineralized films show good biocompatibility through MC3T3‐E1cells test for the potential biomaterials. [ABSTRACT FROM AUTHOR]

Barium titanate (BaTiO3) is a typical perovskite-type oxide with high dielectric constant, low dielectric loss, and excellent ferroelectric, piezoelectric, pyroelectric, and other properties. In view of the low photogenerated electron-hole separation efficiency of T-BT itself, it is proposed to prepare nanocomposites with good catalytic performance by compound modification with Ag. Considering repeated use, on the basis of powder catalysis, a porous block is prepared by compounding powder and organic polymer PVDF. In this study, the t-BaTiO3/Ag/β-PVDF composite material with porosity of ∼70.4% was prepared with the raw material of PVDF and piezoelectric t-BaTiO3/Ag. The mechanical and piezoelectric photocatalytic properties of the composite material was studied systematically. The piezoelectric coefficient d 33 is 1.44 pC/N which can be explained by COMSOL simulation calculation. Moreover, the compressive strength is 1.76 MPa. The degradation MO and RhB results indicated that t-BaTiO3/Ag/β-PVDF composite material had good degradation and cycle stability. [ABSTRACT FROM AUTHOR]

In recent years, porous titanium (Ti) scaffolds with BaTiO3 coatings have been designed to promote bone regeneration. However, the phase transitions of BaTiO3 have been understudied, and their coatings have yielded low effective piezoelectric coefficients (EPCs < 1 pm/V). In addition, piezoelectric nanomaterials bring many advantages in eliciting cell-specific responses. However, no study has attempted to design a nanostructured BaTiO3 coating with high EPCs. Herein, nanoparticulate tetragonal phase BaTiO3 coatings with cube-like nanoparticles but different effective piezoelectric coefficients were fabricated via anodization combining two hydrothermal processes. The effects of nanostructure-mediated piezoelectricity on the spreading, proliferation, and osteogenic differentiation of human jaw bone marrow mesenchymal stem cells (hJBMSCs) were explored. We found that the nanostructured tetragonal BaTiO3 coatings exhibited good biocompatibility and an EPC-dependent inhibitory effect on hJBMSC proliferation. The nanostructured tetragonal BaTiO3 coatings of relatively smaller EPCs (<10 pm/V) exhibited hJBMSC elongation and reorientation, broad lamellipodia extension, strong intercellular connection and osteogenic differentiation enhancement. Overall, the improved hJBMSC characteristics make the nanostructured tetragonal BaTiO3 coatings promising for application on implant surfaces to promote osseointegration. [ABSTRACT FROM AUTHOR]

Aims: Carbapenem-resistant K. pneumoniae (CRKP) is the most common carbapenem-resistant Enterobacteriaceae with high mortality. Ceftazidime-avibactam (CAZ-AVI) has exhibited excellent in vitro activity in vivo against CRKP. However, the efficacy of CAZ-AVI in KPC-producing CRKP-infected patients with different kidney statuses varies, such as renal insufficiency, normal renal function, and augmented renal clearance (ARC). We explored the use of therapeutic drug monitoring (TDM) to evaluate the concentration and efficacy of CAZ-AVI in CRKP-infected patients with different kidney statuses. Methods: Serum concentrations for CAZ and AVI were determined by the high-performance liquid chromatography method. Bacterial identification, routine susceptibility testing, renal function index, and others were performed in standard protocols in the hospital's clinical laboratories. Results: In the two patients with ARC, in case 1, CAZ-AVI 2.5g q6h was used with good efficacy, and the concentrations were up to the pharmacokinetics/pharmacodynamics targets. In Case 2, 2.5 g q8h was used with invalid effectiveness, and AVI Cmin was only 0.797 mg/l, which is lower than the PK/PD target. Case 3 was renal insufficiency using CAZ-AVI 1.25 q8h, and case 4 was normal renal function using 2.5 g q8h. Their concentrations were both up to the PK/PD targets. Conclusion: TDM results demonstrated that CAZ-AVI steady-state plasma concentration varies among patients with different kidney statuses, providing evidence for the utility of TDM of CAZ-AVI in individualized drug dose adjustment. ARC patients may need more CAZ-AVI daily doses than the standard dose. [ABSTRACT FROM AUTHOR]

The orientation, distribution, and contact point density of BF (basalt fiber) in the concrete matrix play significant roles in the mechanical properties of BF concrete, but represent a weak point in current research. It is meaningful to study the morphological characteristics of BF in concrete. In this study, the transparent model test and joint blocking method were innovatively adopted to investigate the correlation of dosage with the BF morphological parameters and concrete mechanical properties. A focus on a BF dosage of 0–7.5 kg/m3 and the contribution index of fibers Cf was defined. Furthermore, NMR and CT techniques were used to observe the changes in the microstructure of BF concrete. The experimental results show that the BF contribution index Cf reaches the largest value when the BF content is around 3 kg/m3, approximately 2.7; in this case, the mechanical properties of BF concrete were also optimal, and the Cf was only 2.34 when the BF content was 7.5 kg/m3. NMR and CT test results show that there is a strong correlation between the BF morphological parameters and the distribution of pore structure in the concrete matrix. The overlapping contact of BF clusters led to the penetration of pores, which led the macro-pore proportion to increase dramatically. The increase in the macro-pore proportion is the main reason for the deterioration in concrete performance. In addition, these macro-pores may have adverse effects on the chloride ion permeability of BF concrete. [ABSTRACT FROM AUTHOR]

Composites with damping–absorption performances and storage-loss behaviors were fabricated based on NCB (nano-carbon black), BWZT [Ba (W1/2Cu1/2)O3–Pb0.98Sr0.02 (Mg1/3Nb2/3)0.275(Ni1/3Nb2/3)0.10(Zr0.25Ti0.375)O3] and RTV (room temperature vulcanizing silicone rubber) employing three steps methods of ball-milling, three-roller milling and pressing. The effects of NCB on storage, loss and damping properties of composites were investigated by the method of DMTA and, absorption and mechanical performances are measured by the methods of standing wave tube and TG separately. The micro, chemical and phase structures of composites are characterized by SEM, XRD and IR. The results indicated that both doping of NCB and the combination of BWZT and RTV can be proposed to improve greatly the comprehensive performance of RTV matrixes and, there would be more excellent comprehensive properties in NCB/BWZT/RTV(NBR) with amount of 4–6 wt.% for NCB as d33 of 81 pC/N, storage modulus of 25003 MPa, loss modulus of 398 MPa, damping coefficient of 0.07–0.12, and absorption coefficients of 0.45–0.55 with the difference of frequency in the range of 400–1600 Hz. Lattice growth of BWZT is found showing strong dependences on contents of NCB, the absorption–damping performance. [ABSTRACT FROM AUTHOR]

Interference between different quantum paths can generate Fano resonance. One of the examples is transport through a quasibound state driven by a time-dependent scattering potential. Previously it is found that Fano resonance occurs as a result of energy matching in one-dimensional systems. In this work, we demonstrate that when transverse motion is present, Fano resonance occurs precisely at the wavevector matching situation. Using the Floquet scattering theory, we considered the transport properties of a nonadiabatic time-dependent well both in a two-dimensional electron gas and monolayer graphene structure. Dispersion of the quasibound state of a static quantum well is obtained with transverse motion present. We found that Fano resonance occurs when the wavevector in the transport direction of one of the Floquet sidebands is exactly identical to that of the quasibound state in the well at equilibrium and follows the dispersion pattern of the latter. To observe the Fano resonance phenomenon in the transmission spectrum, we also considered the pumped shot noise properties when time and spatial symmetry secures vanishing current in the considered configuration. Prominent Fano resonance is found in the differential pumped shot noise with respect to the reservoir Fermi energy. [ABSTRACT FROM AUTHOR]

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The biodegradable material poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffold has good biodegradability, but poor biocompatibility limits its application in the biological field. And it can effectively improve its biological activity by compounding with the bone conduction activity material of Barium titanate (BT). The PHBV and piezoelectric material BT were prepared into porous composite scaffolds with porosity of 45–50%. The mechanical properties and electrical properties of BT/PHBV scaffolds were systematically studied. The results showed that the piezoelectric coefficient d33 was 0.2–1.5 pC/N. Moreover, the compressive strength and elastic modulus were 1.0–2.0 MPa and 100–200 MPa, respectively. The results of degradation and mineralization showed that BT/PHBV scaffolds had good degradation and mineralization performance which was indicated that the materials had good biological activity. [ABSTRACT FROM AUTHOR]

Germanium (Ge), a waste residue leaching from zinc (Zn) smelting process, has potential cementitious properties and could be recycled as a cement supplement activated by chemical reagents. In this work, a test was conducted to determine the hydration properties of Ge slag-cement-based composites with Ge slag (GS)/ordinary Portland cement (PC) contents of 0wt%, 5wt%, 10wt%, 15wt%, 20wt%, and 25wt% and water-to-binder ratio (w/b) of 0.4. The activators Ca(OH)2, AlCl3, NaAlO2, and Na2CO3 were mixed under 1wt%, 2wt%, 3wt%, and 4wt% dosages of GS weight. The composition and microstructure of the hydration products were investigated by the combined approaches of X-ray diffraction (XRD), thermogravimetry–differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). First, the GS cementitious property is attributed to the high content of CaSO4•2H2O. Second, the activators affected the acceleration performance in the following order: NaAlO2, Na2CO3, AlCl3, and Ca(OH)2. More importantly, the 28-day unconfined compressive strength (UCS) is 45.34 MPa at the optimum formula of 0.6wt% NaAlO2, 15wt% GS, and 85wt% PC, which is 9.16% higher than the control. Thus, NaAlO2 is beneficial for the ettringite (AFt) generation, resulting in the C–S–H structure compaction. However, the Zn2+ residue inhibited the AFt formation, representing an important challenge to the strength growth with curing age. Consequently, the GS could be recycled as a supplement to the cement under the activator NaAlO2. [ABSTRACT FROM AUTHOR]

Thickening performance is greatly influenced by aggregate densification and channelling development; however, the microstructures of aggregates and channelling are unable to directly observe because of high turbidity mud bed during thickening. Computed tomography scan imaging technique has been introduced to investigate the effects of aggregate densification and channelling in the mud bed samples during unclassified tailings thickening. The samples were prepared through deep-freezing and freeze-drying techniques, immediately after sampling from the operation of a pilot thickener. Based on the information of void ratio, pore-size distribution, and permeability, obtained from 3D reconstruction images of the aggregates structure, aggregate densification and channelling development have been characterized. Channelling patterns have been classified by the size and shape of the connection throat of the pore between aggregates. As the aggregate structure broke and densified, the void ratio and pore size of the mud bed were decreased. Thickening performance enhancement was predicted based on solid flux and permeability of mud bed, and the result indicated raking on aggregate densification and channelling apparently improves the unclassified tailings dewatering extent. [ABSTRACT FROM AUTHOR]

Abstract: Plate‐like and nanoparticle barium titanate (BaTiO3 [BT]) films are synthesized on Ti substrate by low temperature reaction using Ti, Ba(AC)2, and NaOH as raw materials. The films are characterized by XRD, SEM, TEM, and photoluminescence spectroscopy (PL) to obtain sizes, crystal structure, and emission peaks. The results show that BaTiO3 plate‐like films can be obtained at 140 °C for 4 h have a stronger (110) diffraction peak than other conditions. The diameter is 2.08.0 µm. BaTiO3 nanoparticle films are obtained via changing the reaction order and the average diameter is 30 nm. The adhesion strength of BaTiO3 plate‐like film is 16.9 MPa and that of the nanoparticle film is 13.6 MPa. It is shown in PL results that the emission peaks of plate‐like films are from 663 to 691 nm. Finally, a solubility–crystallization mechanism and an in situ crystallization mechanism are proposed to explain the formation process of BaTiO3 plate‐like films and nanoparticle films, respectively. [ABSTRACT FROM AUTHOR]

Rational nutritional support shall be based on nutritional screening and nutritional assessment. This study is aimed to explore nutritional risk screening and its influencing factors of hospitalized patients in central urban area. It is helpful for the early detection of problems in nutritional supports, nutrition management and the implementation of intervention measures, which will contribute a lot to improving the patient's poor clinical outcome. A total of three tertiary medical institutions were enrolled in this study. From October 2015 to June 2016, 1202 hospitalized patients aged ≥18 years were enrolled in Nutrition Risk Screening 2002 (NRS2002) for nutritional risk screening, including 8 cases who refused to participate, 5 cases of same-day surgery and 5 cases of coma. A single-factor chi-square test was performed on 312 patients with nutritional risk and 872 hospitalized patients without nutritional risk. Logistic regression analysis was performed with univariate analysis ( P<0.05), to investigate the incidence of nutritional risk and influencing factors. The incidence of nutritional risk was 26.35% in the inpatients, 25.90% in male and 26.84% in female, respectively. The single-factor analysis showed that the age ≥60, sleeping disorder, fasting, intraoperative bleeding, the surgery in recent month, digestive diseases, metabolic diseases and endocrine system diseases had significant effects on nutritional risk ( P<0.05). Having considered the above-mentioned factors as independent variables and nutritional risk (Y=1, N=0) as dependent variable, logistic regression analysis revealed that the age ≥60, fasting, sleeping disorders, the surgery in recent month and digestive diseases are hazardous factors for nutritional risk. Nutritional risk exists in hospitalized patients in central urban areas. Nutritional risk screening should be conducted for inpatients. Nutritional intervention programs should be formulated in consideration of those influencing factors, which enable to reduce the nutritional risk and to promote the rehabilitation of inpatients. [ABSTRACT FROM AUTHOR]

Monodisperse plate-like α-Fe2O3nanoparticles have been successfully prepared by hydrothermal synthetic route using Fe(NO3)3, NaOH, and KBH4reacted at 180°C for 12 h. From the investigation of X-ray diffraction and FT-IR spectra, the α-Fe2O3nanoparticles can be directly prepared by the hydrothermal method. Transmission electron microscope and scanning electron microscope observation revealed that the α-Fe2O3nanoparticles had average diameters were about 150 nm. Magnetic properties have been detected by a vibrating sample magnetometer at room temperature. The nanoparticles exhibited a ferromagnetic behavior and the coercive force (Hc), saturation magnetization (Ms), and remanent magnetization (Mr) were 344.75 Oe, 0.534 emu/g, and 0.012 emu/g, respectively. [ABSTRACT FROM AUTHOR]

Biscuit-like CuO have been prepared via a thermal decomposition reaction of CuC2O4at 300–500ºC for 1 h. The morphology and structure of the synthesized biscuit-like structures were characterized by X-ray diffraction, field emission scanning electron microscope, transmission electron microscope, and Fourier transform infrared spectroscopy. The results show that these biscuit-like CuO presents monoclinic structure and typical diameters of 1.0–2.0 µm with a self-assembly of nanocrystals, which average diameter was about 25 nm. The as-prepared CuO nanostructure has a high surface area of about 82.71 m2/g. Finally, a possible growth mechanism was also proposed to explain the formation of biscuit-like CuO. [ABSTRACT FROM AUTHOR]

Chronic stress is a known risk factor for both endothelial dysfunction and cardiovascular disease (CVD), but less is known of how acute mental stress affects the vasculature. In this systematic review and meta-analysis, we analyzed the impact of acute mental stress on flow-mediated dilation (FMD), an indicator of endothelial function. We searched the Medline, Cochrane, EMBASE, and ISI Web of Knowledge databases through May 2014, to identify publications in English-language journals. The primary outcome was the change in FMD from baseline to the time of measurement. We also assessed the risk of bias and the heterogeneity of included studies. Our search identified eight prospective studies, which displayed significant heterogeneity. Four studies measured FMD while the subject was performing the task; six measured FMD after the task had been completed. The total number of participants was 164. The pooled results indicate that FMD did not change significantly while the task was being performed (pooled difference in means: −0.853; 95 % confidence interval (CI), −3.926/2.220; P = 0.586); however, FMD measured after the task was completed was significantly less than baseline (pooled difference in means: −2.450; 95 %CI, −3.925/−0.975; P = 0.001). In conclusions, our findings provide evidence that an acute stressful experience has a delayed, negative impact on the function of the endothelium. Repeated exposure to short-term stress may lead to permanent injury of the vasculature. Therefore, assessment of patients' exposure to both repeated acute mental stress and chronic stress may be useful in determining their risk of developing CVD. [ABSTRACT FROM AUTHOR]

The Tangjiaping molybdenum deposit, discovered in 2006, is a large-scale porphyry molybdenum deposit. The studies of its basic geological work and metallogenic regularity have been completed by previous researchers with conventional geological methods. The results showed that the Tangjiaping molybdenum deposit belongs to the plutonic hypabyssal porphyry molybdenum deposit and the Tangjiaping granodiorite porphyry molybdenum mineralization acts as a mother rock mining area. However, there is no proof that the metallogenic regularity is from the perspective of mineralogy. From the mineralogy angle four kinds of typomorphic characteristics (chemical composition, trace elements, crystal structure, lattice parameters, structure etc. ) of molybdenite, pyrite, quartz, and feldspar from the Tangjiaping molybdenum mine were studied using the separation of single mineral to chemical analysis, X-ray Diffraction and rock mineral identification technology. The results are: 1 the mining area of molybdenite is 2H type, and the content of Re component is very low; the δ34S of molybdenite values is 3. 0‰; sulfur isotopic changes in a small range close to the meteorite sulfur with the characteristics of deep source sulfur, indicating that the sulphur is derived from the granite porphyry. 2 pyrite is rich in trace elements Mo, Go, Cu, poor Ni, Pb, Zn, in addition, low content of Ag and Au, S/Se is greater than 250000, which is consistent with the 'S/Se more than 250000 - 500000 area could not find gold' conclusion. 3 quartz is rich in Mo. δ18 O in mineralization quartz veins are lower, showing a small amount of precipitation appeared in the hydrothermal alteration during the later mineralization. 4 feldspar is rich in Mo. Light rare earth (La-Nd) content is higher than that of rare earth (Sm-Ho) content and heavy rare earth (Er-Y) content. Potassium feldspar degree of ordering, triclinic and structure parameter values were higher. Potassium feldspar structure at low temperature, shows that the potassium feldspar in this area is triclinic symmetry microcline at low temperature conditions, and it is the product of hydrothermal activity; rock potash feldspathization characteristics of molybdenum mineralization is the most favorable. The Tangjiaping molybdenum deposit therefore belongs to the plutonic hypabyssal porphyry molybdenum deposit, and this paper has important significance for the summarization of porphyry type molybdenum ore metallogenic regularity and prospecting marks. [ABSTRACT FROM AUTHOR]

We use the Floquet scattering theory to study the correlation properties of the nonadiabatic pumped dc current and heat flow through a time-dependent quantum well. Electrons can transit through the quasibound state to the oscillator induced Floquet states leading to resonant tunneling effect. Virtual electron scattering processes can produce pumped heat flow, pumped shot noise and pumped heat flow noise, with presence of time and spatial reversal symmetry. When one of the Floquet levels matches the quasibound level there strikes a 'Fano' resonance. [ABSTRACT FROM AUTHOR]

Tap water (unfiltered), filtered tap water and processed bottled water (purified water, artificial mineralized water, or natural water) are now the five most widely consumed types of drinking water in China. However, the constituents (organic chemicals and inorganic ingredients) of the five waters differ, which may cause them to have different long-term health effects on those who drink them, especially sensitive children. In order to determine which type of water among the five waters is the most beneficial regarding reproductive outcomes and the developmental behaviors of offspring, two generations of Sprague–Dawley rats were given these five waters separately, and their reproductive outcomes and the developmental behaviors of their offspring were observed and compared. The results showed that the unfiltered tap water group had the lowest values for the maternal gestation index (MGI) and offspring's learning and memory abilities (OLMA); the lowest offspring survival rate was found in the purified water group; and the highest OLMA were found in the filtered tap water group. Thus, the best reproductive and offspring early developmental outcomes were found in the group that drank filtered tap water, which had the lowest levels of pollutants and the richest minerals. Therefore, thoroughly removing toxic contaminants and retaining the beneficial minerals in drinking water may be important for both pregnant women and children, and the best way to treat water may be with granular activated carbon and ion exchange by copper zinc alloy. [ABSTRACT FROM AUTHOR]

A facile method of synthesizing polycrystalline rod-like γ-Fe2O3from inexpensive, nontoxic precursors FeC2O4via a thermal decomposition reaction of 300–500°C for 1 h has been developed. A ligand directed growth mechanism was proposed for the magnetic anisotropic structure formation and the aspect heat treatment temperatures change. The morphology and structure of the synthesized rod-like γ-Fe2O3were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The results show that these rod-like γ-Fe2O3presents cubic structure and typical diameters of 1.0–2.0 μm with a self-assembly of nanoparticles and average diameter of about 36 nm. The as-prepared rod-like γ-Fe2O3have a high surface area of about 102.03 m2/g. Compared with previous methods; this present method shows an easy processing and can be applied on the large-scale produce of rod-like γ-Fe2O3. [ABSTRACT FROM PUBLISHER]

Increasing evidence shows that dysregulation of microRNAs is correlated with tumor development. This study was performed to determine the expression of miR-141 and investigate its clinical significance in pancreatic ductal adenocarcinoma (PDAC). Taqman quantitative RT-PCR was used to detect miR-141 expressions in 94 PDAC tissues and 16 nontumorous pancreatic tissues. Correlations between miR-141 expression and clinicopathologic features and prognosis of patients were statistically analyzed. The effects of miR-141 expression on growth and apoptosis of PDAC cell line (PANC-1) were determined by MTT, colony formation, and flow cytometry assays. Potential target genes were identified by luciferase reporter and Western blot assays. The expression level of miR-141 in PDAC tissues was significantly lower than that in corresponding nontumorous tissues. Downregulation of miR-141 correlated with poorer pT and pN status, advanced clinical stage, and lymphatic invasion. Also, low miR-141 expression in PDAC tissues was significantly correlated with shorter overall survival, and multivariate analysis showed that miR-141 was an independent prognostic factor for PDAC patients. Further, functional researches suggested that miR-141 inhibits growth and colony formation, and enhances caspase-3-dependent apoptosis in PANC-1 cells by targeting Yes-associated protein-1 (YAP1). Therefore, miR-141 is an independent prognostic factor for PDAC patients, and functions as a tumor suppressor gene by targeting YAP1. [ABSTRACT FROM AUTHOR]

CuFe2O4nanoparticles have been obtained by heat treatment of coprecipitation product, which were synthesis by reaction of Cu2+ions and Fe3+in alkaline condition. The morphology and microstructure of the synthesized urchin-like superstructures have been characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the CuFe2O4nanoparticles were polycrystal with cubic jacobsite structure and a size distribution from 20 to 40 nm. Magnetic properties have been detected by a vibrating sample magnetometer at room temperature. The nanoparticles exhibited a ferromagnetic behavior with the coercive force (Hc) value of 86.83Oe, saturation magnetization (Ms) value of 37.98 emu/g and remanent magnetization (Mr) value of 2.68 emu/g. The IR spectrum of peak at 586 cm−1was corresponding to the vibration modes of CuFe2O4nanoparticles. [ABSTRACT FROM PUBLISHER]

Magnetite Fe3O4 octahedral microcrystals have been successfully synthesized from K4 [Fe (CN)6] and NaOH reagents via a simple hydrothermal process. The morphology and structure of products were characterized by XRD, SEM, and TEM. Magnetic property was detected by a vibrating sample magnetometer at room temperature. The results showed that the prepared Fe3O4 octahedral microcrystals were single crystals with face-center cubic structure and a size distribution from 0.5 to 1.0 μm. The octahedral microcrystals exhibited a ferromagnetic behavior with the coercive force (Hc), saturation magnetization (Ms), and remanent magnetization (Mr) of 70.02 Oe, 71.57 emu/g, and 4.90 emu/g, respectively. It was also found that the NaOH solution and reaction temperature had an important effect on the formation of Fe3O4 octahedra. A possible mechanism was proposed to account for the growth of Fe3O4 octahedra. [ABSTRACT FROM AUTHOR]

MnFeO octahedra have been prepared by reaction of Mn ions and Fe in alkaline condition via heat treatment of the coprecipitation product. The as-prepared powders were characterized in detail by conventional techniques such as powder x-ray diffraction; field emission electron microscopy and transmission electron microscopy. Vibrating sample magnetometer was used to determine the magnetic properties at room temperature. The results show that the MnFeO octahedra were single crystals with cubic jacobsite structure and a size distribution from 0.8 to 1.0 μm. The octahedra obtained at 1100 and 1200 °C exhibited a ferromagnetic behavior with the coercive force ( H) value of 49.03 and 39.23 Oe, saturation magnetization ( M) value of 42.93 and 47.98 emu/g and remanent magnetization ( M) value of 2.16 and 2.55 emu/g, respectively. It is indicated that the heat treatment temperature has a significant effect on the formation of the jacobsite structure. Furthermore, a possible mechanism was also proposed to account for the growth of these products. [ABSTRACT FROM AUTHOR]

Three 1-D reduced molybdenum(V) phosphates, [Ni(OH)2][Na2(H2O)3]2{Ni[(MoO2)6(OH)3(HPO4)3(PO4)]2} · 2C6H14N2 · 2H3O · 5H2O (1), [Ni(H2O)2][K(H2O)5]2{Ni[(MoO2)6(OH)3(HPO4)3(PO4)]2} · 2C6H14N2 · 2H3O · 4H2O (2), and [Cu(H2O)2][Na(H2O)5]2{Cu[(MoO2)6(OH)3(HPO4)3(PO4)]2} · 2C6H14N2 · 2H3O · 4H2O (3), have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The crystallographic analysis reveals that 1 is based on {Ni[Mo6O12(OH)3(HPO4)3(PO4)]2} clusters connected through {[Ni(OH)2][Na2(H2O)3]2} pentanuclear mixed-metal cluster units to yield unusual 1-D chains along the c-axis, which further form 3-D supramolecular networks via hydrogen-bonding. Compounds 2 and 3 are heterogeneous isostructural compounds. Both are built from M[Mo6P4]2 (M = Ni or Cu) blocks as the structural motif combined with [MO4(H2O)2] (M = Ni or Cu) octahedra to form 1-D chains, where M[Mo6P4]2 (M = Ni or Cu) is bonded by [M′(H2O)5] (M′ = K or Na). Furthermore, bulk carbon paste electrode modified with 1 (1-CPE) displays good electrocatalytic activity toward reduction of nitrite or bromate. [ABSTRACT FROM PUBLISHER]

Physicochemical and biological parameters related to water quality and microcystins (MCs) contamination in aquatic environment of the Three Gorges Reservoir were investigated in August 2004 and January 2005. A solid-phase extraction method and an HPLC equipped with photodiode array were used for MC-LR detection. A quantitative analysis showed the total MC-LR concentrations of water samples ranged from non-detectable to 0.57 $\upmu $g L among the seven sampling sites. The highest MC-LR concentration was found at sampling site G (Wushan), which was followed by F (Kaixian), E (Wanzhou), D (Fuling), C (Cuntan), and A (Daxigou). The correlation analysis showed the MC-LR concentration was positively correlated with chlorophyll-a concentration. This result suggests that MC concentration in water can be indirectly estimated by analyzing the chlorophyll-a concentration. Overall, the results of this study suggest that more importance should be placed on monitoring of MC contamination and water quality in the Three Gorges Reservoir to ensure drinking water safety and reduce the potential exposure of people to these health hazards. [ABSTRACT FROM AUTHOR]

Sea urchin-like and plates CuO nanostructured have been prepared via a thermal decomposition reaction of CuC2O4 at 300°C for 1 h. The morphology and structure of the synthesized sea urchin-like structures were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The results show that these sea urchin-like and plates CuO nanostructured presents monoclinic structure and typical diameters of 300 to 500 nm with a self-assembly of nanoparticles and average diameter of about 23 nm. The as-prepared CuO nanostructured have a high surface area of about 39.83 m2/g. Finally, a possible growth mechanism was also proposed to explain the formation of sea urchin-like and plates CuO nanostructured. [ABSTRACT FROM AUTHOR]

Two rare 12-tungstovanadate-bipyridine inorganic-organic hybrid compounds, [VW12O40] · 2(4,4'-H2bipy) · 2H2O (1) and [VW12O40] · 4(2,2'-Hbipy) (2), have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction and IR analysis. In 1, a 2-D supramolecular architecture is formed by hydrogen-bonding between [VW12O40]4- and bipy. Compound 1 shows good activity for photocatalytic reduction of rhodamine B in a liquid-solid system. The electrochemical and electrocatalytic properties of 2-bulk carbon paste electrode modified with 2 were investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Fe3O4 nanorods and Fe2O3 nanowires have been synthesized through a simple thermal oxide reaction of Fe with C2H2O4 solution at 200–600°C for 1 h in the air. The morphology and structure of Fe3O4 nanorods and Fe2O3 nanowires were detected with powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The influence of temperature on the morphology development was experimentally investigated. The results show that the polycrystals Fe3O4 nanorods with cubic structure and the average diameter of 0.5–0.8 μm grow after reaction at 200–500°C for 1 h in the air. When the temperature was 600°C, the samples completely became Fe2O3 nanowires with hexagonal structure. It was found that C2H2O4 molecules had a significant effect on the formation of Fe3O4 nanorods. A possible mechanism was also proposed to account for the growth of these Fe3O4 nanorods. [ABSTRACT FROM AUTHOR]

Magnetite Fe3O4 walnut spherical particles and octahedral microcrystals were successfully synthesized from K4 [Fe (CN)6], K3 [Fe (CN)6] and NaOH reagents via a simple hydrothermal process. And the uniform morphology of octahedral microcrystals was obtained in the presence of ethylene glycol. The morphology and structure of products were characterized by powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the Fe3O4 walnut spherical particles and octahedral microcrystals were single crystals with the face-center cubic structure and with size distributions from 2.2 to 8.6 μm and 1.6 to 12.5 μm, respectively. Their magnetic properties were detected by a vibrating sample magnetometer at room temperature. The walnut spherical particles exhibited a ferromagnetic behavior with the coercive force (Hc), saturation magnetization (Ms) and remanent magnetization (Mr) being 150.57 Oe, 97.634 and 12.05 emu/g, respectively. For the octahedral microcrystals they were 75.28 Oe, 101.90 and 6.69 emu/g, respectively. Different sizes of walnut spherical particles were controlled synthesized through adjusting the NaOH concentration. It was found that ethylene glycol molecules have a significant effect on the formation of Fe3O4 octahedra. A possible mechanism was also proposed to account for the growth of these Fe3O4 products. [ABSTRACT FROM AUTHOR]