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Preoperative nutritional status plays an important role in predicting postoperative outcomes. Prognostic Nutritional Index (PNI) and Controlling Nutritional Status (CONUT) are good tools to assess patients’ nutritional status. They have been used in predicting outcomes in various malignancies, but few studies have focused on pancreatic adenocarcinoma (PDAC) patients. Totally, 306 PDAC patients were enrolled. The propensity score matching (PSM) method was introduced to eliminate the baseline inequivalence. Patients with different PNI (or CONUT) scores showed inequivalence baseline characteristics, and patients with compromised nutritional status were related with a more advanced tumour stage. After PSM, the baseline characteristics were well balanced. Both low PNI (≤45) and high CONUT (≥3) were independent risk factors for poor overall survival (P < 0·05), and the result remained the same after PSM. Survival analysis demonstrated both patients with low PNI and high CONUT score were associated with poorer survival, and the result remained the same after PSM. The results of AUC indicated that CONUT might have a higher sensitivity and specificity in predicting complications and survival. Preoperative low PNI (≤45) and high CONUT (≥3) scores might be reliable predictors of prognosis and surgical complications in PDAC patients. Compared with PNI, CONUT might be more effective.
Radiocarbon (14C) has become a unique and powerful tracer in source apportionment of atmospheric carbonaceous particles. In this study, the Asia Pacific Economic Cooperation summit (APEC) held in Beijing in 2014 was used as a demonstration to research the source apportionment of atmosphere PM2.5. We used a 200 kV single stage accelerator mass spectrometer recently completed at China Institute of Atomic Energy (CIAE). The PM2.5 samples related to above case were collected, and the characteristics of radiocarbon in organic carbon (OC) and elemental carbon (EC) in samples were analyzed using the AMS. The results show that the Before-APEC pollution emission mode is different from the During-APEC and After-APEC pollution emission modes. For Before-APEC, During-APEC and After-APEC, the average values of fossil carbon fraction of OC are 0.463, 0.431 and 0.615, respectively, and those of EC are 0.644, 0.561 and 0.687. The fossil source contributions of traffic activities using fossil fuels to OC and EC are 15.8 % and 21.9 %, respectively. The fossil source contributions of industrial activities to OC and EC are 38.0 % and 8.2 %, respectively. It is about 7–10 days that is needed to take to regenerate the PM2.5 pollution caused by human activities.
Rabbits play an important role in people’s lives due to their high nutritional value and high-quality hair that can be used as raw material for textiles. Furthermore, rabbits are an important animal model for human disease, as genome-edited animals are particularly valuable for studying gene functions and pathogenesis. Somatic cell nuclear transfer (SCNT) is an important technique for producing genome-edited animals and it has great value in saving endangered species and in clone stem cell therapy. However, the low efficiency of SCNT limits its application, with the selection of suitable rabbit oocytes being crucial to its success. In the present study, we collected oocytes from ovarian follicles and stained them with 26 μM brilliant cresyl blue (BCB). We then matured the oocytes in vitro and used them for SCNT. Comparison of the BCB-positive oocytes with BCB-negative oocytes and the control group showed that the BCB-positive group had a significantly higher maturation rate (81.4% vs. 48.9% and 65.3% for the negative and control groups, respectively), cleavage rate (86.6% vs. 67.9% and 77.9%), blastocyst rate (30.5% vs. 12.8% and 19.6%), total number of blastocysts (90±7.5 vs. 65.3±6.3 and 67.5±5.7), and inner cell mass (ICM)/ trophectoderm (TE) index (42.3±4.2 vs. 30.2±2.1 and 33.9±5.1) (P<0.05). The BCB-positive group had a significantly lower apoptosis index (2.1±0.6 vs. 8.2±0.9 and 6.7±1.1 for the negative and control groups, respectively) (P<0.05). These findings demonstrate that BCB-positive oocytes have a higher maturation ability and developmental competence in vitro, indicating that BCB staining is a reliable method for selecting oocytes to enhance the efficiency of SCNT.
Scabies is a parasitic disease caused by the ectoparasite Sarcoptes scabiei, affecting different mammalian species, including rabbits, worldwide. In the present study, we cloned and expressed a novel inorganic pyrophosphatase, Ssc-PYP-1, from S. scabiei var. cuniculi. Immunofluorescence staining showed that native Ssc-PYP-1 was localized in the tegument around the mouthparts and the entire legs, as well as in the cuticle of the mites. Interestingly, obvious staining was also observed on the fecal pellets of mites and in the integument of the mites. Based on its good immunoreactivity, an indirect enzyme-linked immunosorbent assay (ELISA) using recombinant Ssc-PYP-1 (rSsc-PYP-1) as the capture antigen was developed to diagnose sarcoptic mange in naturally infected rabbits; the assay had a sensitivity of 92·0% and specificity of 93·6%. Finally, using the rSsc-PYP-1-ELISA, the Ssc-PYP-1 antibody from 10 experimentally infected rabbits could be detected from 1 week post-infection. This is the first report of S. scabiei inorganic pyrophosphatase and the protein could serve as a potential serodiagnostic candidate for sarcoptic mange in rabbits.
Bragg coherent X-ray diffraction imaging has been used to determine the structure of the initial clusters of α-Fe nano crystals which form upon annealing of an iron-based amorphous alloy or metallic glass. The method is able to identify the shapes and strain of these crystallites without any need for cutting the sample, so can visualize them in three dimensions in their intact state. In this way, the delicate dendritic structures on the exterior of the crystallites can be seen and its density versus radius relationship identifies a fractal dimension of the porous region that is consistent with diffusion-limited aggregation models. The crystal sizes were found to be around 60 nm after annealing at 700 °C growing to about 330 nm after annealing at 750 °C. This article introduces the BCDI method and describes its application to characterize previously recrystallized samples of iron-based amorphous alloys. It paves the way for a possible future in situ nucleation/growth investigation of the relationship between kinetics and nanostructure of metallic glass.
Schizophrenia (SZ) is suggested to be a complex polygenetic disorder with high heritability. Genome-wide association studies have found that the rs1635, rs11038167, and rs10489202 polymorphisms are associated with SZ in Han Chinese. However, results of validation studies are inconsistent. This study aimed to test the association between the NKAPL rs1635, TSPAN18 rs11038167, and MPC2 rs10489202 polymorphisms and SZ in a Chinese population.
This study contained 700 unrelated SZ patients (300 Zhuang and 400 Han) and 700 gender- and age-matched controls (300 Zhuang and 400 Han). The polymorphisms in TSPAN18 (rs11038167), NKAPL (rs1635), and MPC2 (rs10489202) were genotyped using the Sequenom MassARRAY method. Statistical analyses were performed with PLINK program and SPSS l6.0 for Windows. STATA11.1 was used for meta-analysis.
No statistically significant difference was found in different allele and genotype frequencies of rs1635, rs11038167, and rs10489202 between SZ cases and controls of Zhuang and Han ethnicities and the total samples (all p>0.05). Further meta-analysis suggested that single-nucleotide polymorphism rs10489202 was significantly associated with SZ in a Han Chinese population (pOR=0.002).
Our case–control study failed to validate the significant association of NKAPL rs1635, TSPAN18 rs11038167, and MPC2 rs10489202 polymorphisms with SZ susceptibility in the southern Zhuang or Han Chinese population. However, meta-analysis showed a significant association between MPC2 variant rs10489202 and SZ susceptibility in Han Chinese.
We present results of a regional comparative study of surface mass changes from 2004 to 2008 based on Gravity Recovery and Climate Experiment (GRACE), The Ice, Cloud and Land Elevation Satellite (ICESat) and CHINARE observations over the Lambert Glacier/Amery Ice Shelf system (LAS). Estimation of the ICESat mass change rates benefitted from the density measurements along the CHINARE traverse and a spatial density adjustment method for reducing the effect of spatial density variations. In the high-elevation inland region, a positive trend was estimated from both ICESat and GRACE data, which is in line with the CHINARE accumulation measurements. In the coastal region, there were areas with high level accumulations in both ICESat and GRACE trend maps. In many high flow-speed glacier areas, negative mass change rates may be caused by dynamic ice flow discharges that have surpassed the snow accumulation. Overall, the mass change rate estimate in the LAS of 2004–2008 from the GRACE, ICESat and CHINARE data is 5.41 ± 4.59 Gt a−1, indicating a balanced to slightly positive mass trend. Along with other published results, this suggests that a longer-term positive mass trend in the LAS may have slowed in recent years.
Psychiatric disorders such as schizophrenia and major depressive disorder
(MDD) are likely to be caused by multiple susceptibility genes, each with
small effects in increasing the risk of illness. Identifying DNA variants
associated with schizophrenia and MDD is a crucial step in understanding
the pathophysiology of these disorders.
To investigate whether the SP4 gene plays a significant
role in schizophrenia or MDD in the Han Chinese population.
We focused on nine single nucleotide polymorphisms (SNPs) harbouring the
SP4 gene and carried out case–control studies in 1235
patients with schizophrenia, 1045 patients with MDD and 1235 healthy
controls recruited from the Han Chinese population.
We found that rs40245 was significantly associated with schizophrenia in
both allele and genotype distributions (Pallele = 0.0005, Pallele = 0.004 after Bonferroni correction; Pgenotype = 0.0023, Pgenotype = 0.0184 after Bonferroni correction). The rs6461563
SNP was significantly associated with schizophrenia in the allele
distributions (Pallele = 0.0033, Pallele = 0.0264 after Bonferroni correction).
Our results suggest that common risk factors in the SP4
gene are associated with schizophrenia, although not with MDD, in the Han
In this paper, a novel method is proposed to determine surface residual stress components and their directions based on the spherical indentation. To obtain the direction and the components of a uniaxial or biaxial residual stress, the relationship between the pile-up deformation around an indentation after unloading and the residual stress was firstly systematically studied and established by using numerical simulation. Through theoretical analysis and numerical simulation, we found that the position of the maximum residual stress is dependent on the maximum pile-up around an indentation after unloading. The direction and components of residual stress can be correctly determined by the unique relationship between pile-up after unloading and biaxial residual stress. This conclusion has been verified by the experiment results in the residual stress measurements of a welded specimen with spherical indentation and x-ray diffraction methods. Meanwhile, the influences of friction between the object surface and the indenter, the material hardening exponent of the specimen, and the elastic deformation upon the residual stress are discussed.
The electrical explosion characteristics of Schottky diode for one-shot switch applications were acquired by analysis of photographs of high speed camera and current-voltage histories. Four types of connections among Schottky diode, top electrode and discharge capacitor were studied. Results show that type B has the longest time (1.4 ms) of optical radiation and highest energy consumption, which makes it easier to turn on the switch. The charge flux of plasma was determined to be 24.5 Q/(s m2) by parallel electrode plates method. Atomic emission spectroscopic measurements were devoted to determine plasma temperature and density during electrical explosion. Results show that temperature is between 4000 K and 5000 K, and density is about 1024 m−3. The one-shot switch based on ceramics has been fabricated and characterized and the results show that the peak current and the rise time are about 963.77 A and 381.6 ns, respectively.
Barium strontium titanate (BST) glass-ceramics were fabricated via controlled crystallization with different crystallization routes. Effects of the microwave crystallization and microwave treatment on the microstructure and energy storage properties of the glass-ceramics were systematically investigated. Results showed that microwave crystallization can increase the dielectric constant. In addition, it was found that the microwave process had little impact on the crystallinity (about 90 wt%), but preferred the crystallization of SrAl4O7. Most importantly, the dielectric breakdown strength (BDS) of the glass ceramics was significantly improved from 561.3 to 791.4 kV/cm by the microwave crystallization. And it can be further enhanced to 900.0 kV/cm by conventional crystallization combined with microwave treatment. The corresponding energy densities of samples derived from the microwave processes were increased to 1.05 and 1.13 J/cm3, respectively, compared with the sample fabricated by the conventional crystallization route (0.47 J/cm3).
Al/MoOx nanoenergetic multilayer films (nEMFs) were deposited by magnetron deposition method. The samples with bilayer thicknesses of 75 nm and 225 nm were prepared, respectively, and the total thickness is 3 μm. The as-deposited Al/MoOx nEMFs were characterized with varied analytical techniques, including SEM, XRD, XPS and DSC. Results show that the MoOx films are amorphous, and are composed of MoO3, Mo2O5 and MoO2. The values of heat release in samples are 3524 J/g and 2508 J/g, respectively, and the final products are Mo, MoO2, and Al2O3. Finally, the reaction paths and reaction kinetics of Al/MoOx exothermic reactions were discussed.
This paper exploits an energetic initiator realized by integrating Al/Ni multilayer nanofilms with semiconductor bridge (SCB). The as-deposited nanofilms have been characterized with varied analytical techniques. Results show that distinct nanofilms are sputter deposited in a layered geometry and give a heat of reaction equal to 1134 J/g. The firing tests of the initiators were accomplished using capacitor discharge unit. Results show that the initiators possess several excellent characteristics such as fast ignition time, low power consumption, high output energy and so on. Therefore, Al/Ni multilayer nanofilms are suitable heat source for improving the reliability of SCB initiators.
Phase structures and electrical properties of lead-free piezoelectric (1−x)(Bi0.5Na0.5)TiO3–x(K0.5Na0.5)NbO3 (BNT–xKNN) ceramics with 0.08 ≤ x ≤ 0.19 were systematically investigated. Results showed that a phase transition from a tetragonal to a pseudocubic phase occurred in this system, as KNN content increases. The addition of KNN shifted both the depolarization temperature Td and rhombohedral–tetragonal phase transition temperature TR-T to lower temperatures and tended to enhance the relaxor behavior of the ceramics, which was well explained by the microdomain–macrodomain transition theory with calculating criterion K. At x = 0.10–0.11, Td reached room temperature (RT), which accordingly induced an enhancement of the unipolar strain that peaks at a value of 0.22% was obtained. Furthermore, as the compositions (x = 0.12–0.15) have Td below RT, samples exhibited high electrostrictive response with large electrostrictive coefficient Q33 (0.017–0.019 m4/C2) and good thermostability comparable with that of traditional Pb-based electrostrictors.
The aim of this study was to evaluate the therapeutic effects of osteopontin neutralization treatment on schistosome-induced liver injury in BALB/C mice. We randomly divided 100 BALB/C mice into groups A, B, C, D and group E. Mice in all groups except group A were abdominally infected with schistosomal cercariae to induce a schistosomal hepatopathological model. Mice in group C, D and group E were respectively administered with praziquantel, praziquantel plus colchicine and praziquantel plus neutralizing osteopontin antibody. We extracted mouse liver tissues at 3 and 9 weeks after the ‘stool-eggs-positive’ day, observed liver histopathological changes by haematoxylin-eosin and Masson trichrome staining and detected the expression of osteopontin, alpha-smooth muscle actin (α-SMA) and transforming growth factor-beta (TGF-β1) by immunohistochemistry, RT-PCR and Western blot. We found that praziquantel plus neutralizing osteopontin antibody treatment significantly decreased the granuloma dimension, the percentage of collagen and the expression of osteopontin, α-SMA and TGF-β1 compared to praziquantel plus colchicine treatment in both the acute and chronic stage of schistosomal liver damage (P<0·05). So we believe that the combined regimen of osteopontin immunoneutralization and anti-helminthic treatment can reduce the granulomatous response and liver fibrosis during the schistosomal hepatopathologic course.
This article reports on microstructure and dielectric properties of Ba0.5Sr0.5Ti1−3y/2WyO3 ceramics. Dielectric peaks of the Ba0.5Sr0.5Ti1−3y/2WyO3 ceramics were markedly suppressed, broadened, and shifted to low temperature with increasing content of W. The limit of W incorporating into the barium strontium titanate (BST) lattice was y = 0.02. Two second phases (BaWO4 and Ba2Ti5O12) were formed above the solid solution limit of W in BST. The doping mechanism represents a new approach to develop microwave tunable materials. Dielectric properties of the Ba0.5Sr0.5Ti1−3y/2WyO3 ceramics could be optimized by the content of W. The sample with y = 0.05 had ε′ of 431, quality factor of 365 (at 2.111 GHz), and tunability of 11.5%, which makes a potential candidate for tunable microwave device applications in the wireless communication.
High-dielectric constant all-organic composite films consisting of polyaniline (PANI) filler and poly(butylene succinate) host were synthesized by simple blending process. The chemical structures and morphology of the composite films were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The dielectric properties of the composite films with different filler concentrations were studied in the frequency range of 100–106 Hz. A percolation phenomenon was observed in the composite films with a percolation threshold vc = 19.7% and the dielectric constant was 10 times that of the pure host material. The enhancement in the dielectric constant can be ascribed to Maxwell–Wagner–Sillars polarization and the low-dielectric loss to good dispersion of PANI filler in the host. As the host polymer is biodegradable, it may be applied as a “green” dielectric material.
Recently, semiconductor nanocrystals or quantum dots (QDs) aroused great concern because of their unique properties such as the size-dependent photoluminescence. They have many excellent applications in areas of molecular bioimaging, medical detection and even energy, especially as biosensing and imaging instead of fluorescent dyes. For the bio-safety, however, we should assess the cytotoxicity of QDs before used in biomedical imaging. Here, the cytotoxicity of amino-functionalized CdSe/CdS (CdSe/CdS-NH2) QDs and carboxy-functionalized CdSe/CdS (CdSe/CdS-COOH) QDs was investigated by MTT assay method. According to our findings, both CdSe/CdS-NH2 and CdSe/CdS-COOH have a dose-dependent effect on cell proliferation. The cytotoxicity of QDs varies with storing time of QDs and kinds of cells. The cytotoxicity of QDs modified with -COOH or -NH2 groups both vary with concentrations in positive linear or change with QD storing time in negative linear. The results indicate that CdSe/CdS-COOH QDs have lower toxicity than CdSe/CdS-NH2 QDs. Hela cell is somewhat more sensitive to amino- and carboxy-modified QDs than Bel7404 cell for MTT assays.
Spindle movement, including spindle migration during first meiosis and spindle rotation during second meiosis, is essential for asymmetric divisions in mouse oocytes. Previous studies by others and us have shown that microfilaments are required for both spindle migration and rotation. In the present study, we aimed to further investigate the mechanism controlling spindle movement during mouse oocyte meiosis. By employing drug treatment and immunofluorescence microscopy, we showed that dynamic microtubule assembly was involved in both spindle migration and rotation. Furthermore, we found that the calcium/CaM/CaMKII pathway was important for regulating spindle rotation.