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In evaluating the quality of table eggs and the developmental stages of embryonic eggs, spectroscopic techniques provide greater efficiency than traditional, time-consuming and laborious approaches. This review summarises recent developments in the spectroscopic analysis of table eggs, including the determination of the chemical composition (ratios of performance to standard deviation of 4.38, 2.25, 2.28, 2.31, and 3.03 for fat, moisture, and protein in egg yolk and moisture and protein in egg albumen, respectively, have been reported). A Haugh unit detection accuracy RMSEP (root mean square error of prediction) for quality of 6.29 was obtained by hyperspectral imaging) for table eggs and fertility detection (for white-shell eggs, fertility detection has been realised at a promising rate of 93.5%) and gender determination in hatching eggs. In conclusion, hyperspectral imaging generally outperforms visible or near-infrared reflectance spectroscopy when evaluating both consumption eggs and hatching eggs, and near-infrared reflectance Raman and fluorescence spectroscopy exhibit a strong potential for gender determination prior to hatching. Scientists have attained a correct sexing rate above 90% at 3.5 d of egg incubation without removing the inner shell membrane. In the detection of blood-spot eggs or fertile eggs, eggshell colour proved to be a negative factor.
An experiment was conducted to determine the effects of supplementing different amounts of daidzein in a diet on the growth performance, blood biochemical parameters and meat quality of finishing beef cattle. Thirty finishing Xianan steers were distributed in three groups equilibrated by weight and fed three different dietary treatments (concentrate ratio = 80%): (1) control; (2) 500 mg/kg daidzein and (3) 1000 mg/kg daidzein, respectively. Steers were slaughtered after an 80-day feeding trial. Results showed that daidzein supplementation had no effect on the final body weight, average daily gain and feed conversion rate of steers. Steers fed with 1000 mg/kg daidzein had greater dry matter intake than those fed with control diets. Compared with the control group, the 1000 mg/kg daidzein group had a higher fat thickness, lower shear force and lightness. The pH, drip loss, cooking loss, redness (a*), yellowness (b*), moisture, ash, crude protein and intramuscular fat of the Longissimus dorsi muscle were unaffected by daidzein supplementation. Compared with the control group, the 1000 mg/kg daidzein group significantly increased the serum concentrations of insulin, free fatty acid and Glutamic-pyruvic transaminase. The 500 mg/kg daidzein group significantly increased the serum concentration of tetraiodothyronine compared with the control group. Supplemental daidzein did not affect the blood antioxidant ability and blood immune parameters in serum. In conclusion, daidzein supplementation above 500 mg/day modifies feed intake and metabolic and hormonal profile, with positive and negative effects on meat quality.
Previously, we reported a phylogenetic study of 98 Burkholderia pseudomallei clinical isolates from Hainan, China. Here, we update the B. pseudomallei strain library with 52 strains from newly identified cases dating from 2014 to 2017, analysed by multilocus sequence typing. Twenty-two sequence types (STs) were identified from the 52 cases, illustrating high genetic diversity; five of them (ST1480, ST1481, ST1482, ST1483 and ST1484) were novel. ST46, ST50 and ST58 predominated (34.6%) as was the case in the previous study (35.7%). An e-BURST map of the ST profiles of the two collections of isolates showed their genetic foundation to be largely unchanged. Neighbour-joining tree analysis was suggestive of a close phylogenetic relationship between the novel STs from this series and those first reported from Hainan (ST1105, ST1099, ST55 and ST1095). Moreover, the two novel STs (1481 and 1483) showed close similarity to ST58 which originated in Thailand indicating a close relationship between B. pseudomallei strains from both countries. The previously described allele profiles gmhD-36 and lepA-68 were found for the first time in our strain collections. Our study emphasises the importance of monitoring the epidemiological status and evolutionary trends of B. pseudomallei in China.
The influence of the content of trifluoroacetate (TFA), in the precursor solution, on the critical current density (Jc) of YBa2Cu3O7−x (YBCO) superconducting films was investigated. We found that a TFA/Ba ratio of 0.68 is optimal to obtain high-performance YBCO films. Using this optimal solution, we then developed an ultraviolet (UV) light soaking technique to prepare YBCO films. This resulted in the constituent elements being uniformly distributed in the films, and this then enabled enhanced Jc. The addition of water vapor during the UV soaking process decreased the content of carbon residue in the films, and further increased the Jc of the resulting YBCO films.
Aero-engines usually contain a lot of pipes and cables which have an important influence on product performance and reliability. In this paper, a new pipe routing approach for aero-engines is proposed. First, an adaptive octree modeling method is presented according to the characteristics of the layout space. After considering three types of engineering constraints, the total length of pipelines, the total number of bends and the natural frequency of pipelines are modeled as the optimal objective. Then, a Modified Max-Min Ant System optimization algorithm (MMMAS), which uses layered node selection and dynamic update mechanism, is proposed for pipe routing. For branch pipelines, ant colony searches in groups and parallel to improve the solution quality and speed up the convergence greatly. Finally, numerical comparisons with other current approaches in literatures demonstrate the efficiency and effectiveness of the proposed approach. And a case study of pipe routing for aero-engines is conducted to validate this approach.
The european X-ray observatory (EXOSAT), which was launched in 1983 and which finished operations in April 1986, has brought a rich harvest of results in the period 1984-1987, surveyed here. The EXOSAT payload consisted of three sets of instruments: two low energy imaging telescopes (LE:E<2 KeV), a medium-energy experiment (ME:E=l-50KeV) and a gas scintillation proportional counter (GSPC:E=2-20KeV). Over most of the energy range covered, EXOSAT was not more sensitive than its predecessor, the american EINSTEIN satellite. But the EINSTEIN satellite is far from having exhausted the treasures of the X-ray sky. And EXOSAT, thanks to its elliptical 90-hour orbit, had the extra advantage of being able to make long, continuous observations of interesting objects, lasting up to 72 hours. Thus, EXOSAT was very well suited for variability studies, and many of its most important findings are in this area. EXOSAT observations sample a vide range of astrophysical sources: X-ray binaries, cataclysmic variables and active stars; supernova remnants and the interstellar medium; active galactic nuclei, and clusters of galaxies. Among the highlights, let us mention:
In view of the broad range of topics covered by Commission 48 and the consequent inevitable overlap with other commissions, it is not feasible to produce a comprehensive self-contained report. The commission therefore restricts its report to a selected list of accessible recent review articles and conference reports, where up-to-date summaries of various topics can be found. Such a list is given below.
Meta-analyses support the efficacy of cognitive–behavioural therapy (CBT) for schizophrenia in western cultures. This study aimed to compare the efficacy of CBT and supportive therapy (ST) for patients with schizophrenia in China.
A multicentre randomized controlled, single-blinded, parallel-group trial enrolled a sample of 192 patients with schizophrenia. All patients were offered 15 sessions of either CBT or ST over 24 weeks and followed up for an additional 60 weeks. All measures used were standardized instruments with good reliability and validity. The Positive and Negative Syndrome Scale (PANSS) was used to assess symptoms of schizophrenia. The Schedule for Assessing Insight (SAI) was used to assess patients’ insight and the Personal and Social Performance Scale (PSP) was used to assess their social functioning.
Effect-size analysis showed that patients made rapid improvements in all symptoms, insight and social functioning as measured by the PANSS, SAI and PSP at 12 and 24 weeks and maintained these improvements over the course of the study to 84 weeks. Patients in the CBT group showed significantly greater and more durable improvement in PANSS total score (p = 0.045, between-group d = 0.48), positive symptoms (p = 0.018, between-group d = 0.42) and social functioning (p = 0.037, between-group d = 0.64), with significant differences emerging after completion of therapy.
Both CBT and ST combined with medication had benefits on psychopathology, insight and social functioning of patients with schizophrenia. CBT was significantly more effective than ST on overall, positive symptoms and social functioning of patients with schizophrenia in the long term.
Imprinting control regions (ICRs) play a fundamental role in establishing and maintaining the non-random monoallelic expression of certain genes, via common regulatory elements such as non-coding RNAs and differentially methylated regions (DMRs) of DNA. We recently surveyed DNA methylation levels within four ICRs (H19-ICR, IGF2-DMR, KvDMR, and NESPAS-ICR) in whole-blood genomic DNA from 128 monozygotic (MZ) and 128 dizygotic (DZ) human twin pairs. Our analyses revealed high individual variation and intra-domain covariation in methylation levels across CpGs and emphasized the interaction between epigenetic variation and the underlying genetic sequence in a parent-of-origin fashion. Here, we extend our analysis to conduct two genome-wide screenings of single nucleotide polymorphisms (SNPs) underlying either intra-domain covariation or parent-of-origin-dependent association with methylation status at individual CpG sites located within ICRs. Although genome-wide significance was not surpassed due to sample size limitations, the most significantly associated SNPs found through multiple-trait genome-wide association (MQFAM) included the previously described rs10732516, which is located in the vicinity of the H19-ICR. Similarly, we identified an association between rs965808 and methylation status within the NESPAS-ICR. This SNP is positioned within an intronic region of the overlapping genes GNAS and GNAS-AS1, which are imprinted genes regulated by the NESPAS-ICR. Sixteen other SNPs located in regions apart from the analyzed regions displayed suggestive association with intra-domain methylation. Additionally, we identified 13 SNPs displaying parent-of-origin association with individual methylation sites through family-based association testing. In this exploratory study, we show the value and feasibility of using alternative GWAS approaches in the study of the interaction between epigenetic state and genetic sequence within imprinting regulatory domains. Despite the relatively small sample size, we identified a number of SNPs displaying suggestive association either in a domain-wide or in a parent-of-origin fashion. Nevertheless, these associations will require future experimental validation or replication in larger and independent samples.
X-ray source IGR J17091-3624 was discovered by INTEGRAL observatory on 2003 April (Kuulkers 2003). A outburst was detected with Swift/Burst Alert Telescope (BAT) in late January 2011 (Krimm 2011). IGR J17091-3624 has a similar timing phenomena to microquasar GRS 1915+105(Belloni 2000; Altamirano 2011). We have analyzed the evolution of temporal and spectral characteristic of IGR J17091-3624 during the 2011 outburst. We find that (1) all the QPOs can be divided into two types, QPO-AB and QPO-C, (2) a small outburst tracks clockwise in the HID, (3) the relationship between hardness and disk color temperature forms a V-shape. Those results will give a strong constraint on the disk radiative process.
Lense-Thirring QPO model is a promising model to explain QPO phenomena (Ingram et al. (2009)). In this model the QPO results from Lense-Thirring precession of a optical translucent inner hot flow in a truncated disc geometry. Now we check this model with different types QPO (see (Belloni et al. (2011)) for a recent review) of black hole transient (BHT) GX 339-4 2010 outburst and suggest type C QPOs are mainly coincident with this model prediction while type B QPOs are not.
An inventory of topsoil soil organic carbon (SOC) content in household farms was performed in a village from a red earth region in Jiangxi Province, China in 2003. In this region, the farmland managed by each household is fragmented, consisting of several plots of land that are not necessarily adjacent to each other. A statistical analysis of SOC variation with land use and household management type, and with crop management practices was conducted. Plot size ranged from 0·007 to 0·630 ha with a mean of 0·1 ha, and SOC content ranged from 1·72 to 25·2 g/kg, varying widely with a variety of land management and agricultural practices, arising from individual household behaviours. The mean SOC content in plot size <0·1 ha was 20% lower than in plot size ⩾0·1 ha. SOC of dry crop plots was 70% lower than that in rice paddies, and SOC of plots contracted from the village was almost double that of plots leased from other householders. Moreover, a 30% increase in SOC was observed with green manure cultivation, and a 55% increase under triple cropping. The difference in SOC levels between the least and most favourable cases of household land management and agricultural practice was up to 150%. The results suggest that policies targeted at crop management alone may not deliver the expected SOC benefits if household land management is also not improved.
The silicide formation for Ni/Pd and Pd/Ni bilayers on Si(100) substrates was investigated. X-ray diffraction and photoelectron spectroscopy (XPS) depth profiling have been applied to study the phase formation of the silicide. We found that with addition of Pd into Ni/Si, a uniform layer of ternary Ni1−xPdxSi layer formed and kept stable for a wide temperature range. The lattice parameter of Ni1−xPdxSi as a function of Pd addition was calculated. The nucleation temperature of NiSi2 was delayed due to the addition of Pd. The higher the Pd addition, the larger the increase in NiSi2 nucleation temperature. We also studied the effect on the addition of Ni to the Pd/Si reaction. For pure Pd/Si reaction PdSi nucleated from Pd2Si at 750°C or above. For Ni/Pd/Si reaction, Pd2Si changed to Ni1−xPdxSi at temperature lower than 750°C due to the incorporation of Ni. The phenomena were explained by classic nucleation theory taking into account the effect of mixing entropy effect.
We report a new method for synthesizing Ge nano-crystallites embedded in SiNy film matrices. On the basis of the effect of the reactant precursors and preferential chemical bonding of Si-N and Ge-Ge, thin films with Ge clusters embedded in SiNy matrices have been prepared in the PECVD system with reactant gases of SiH4, GeH4 and NH3 mixed in the hydrogen plasma. The as-deposited films were then crystallized by Ar ion laser annealing or thermal annealing technique to form nanometer-sized Ge crystallites.
The composition and microstructures of these new type of sample were characterized by infrared absorption spectra, transmission electron microscopy, X-ray diffraction and Raman scattering spectra. The results indicated that the average size of Ge crystallites was estimated to be 2-20 nm depending on the deposition and annealing parameters and can be controlled by a designed manner.
A modified pin-on-disc wear test technique and conversion electron M6ssbauer spectroscopy (CEMS) have been used to characterize the tribological and microstructural properties, respectively, of pure Fe implanted with N and Ar ions at high current densities. CEMS measurements were made before and after wear testing. For the lubricated, mild adhesive wear conditions used here, no evidence was found for iron-nitride dissolution or N atom migration. Disordering of γ'-Fe4N did occur as a result of the wear process. All Nimplanted surfaces were tribologically superior to the Ar-implanted surface and an extremely wear-resistant surface layer about 30-50 nm thick was produced with a dose of 8x1016 N atoms/cm2, at a dose rate of 100 μA/cm2. However, once this layer was worn away the wear rate returned sharply to that of unimplanted pure Fe. A high retained N dose has been observed even for a dose rate of 750 μA/cm2 during which the sample reached 280°C.
A modified pin-on-disc wear test technique and conversion electron Mössbauer spectroscopy (CEMS) have been used to characterize the tribological and microstructural properties, respectively, of pure Fe implanted with N and Ar ions at high current densities. CEMS measurements were made before and after wear testing. For the lubricated, mild adhesive wear conditions used here, no evidence was found for iron-nitride dissolution or N atom migration. Disordering of γ'-Fe4N did occur as a result of the wear process. All Nimplanted surfaces were tribologically superior to the Ar-implanted surface and an extremely wear-resistant surface layer about 30–50 nm thick was produced with a dose of 8×1016 N atoms/cm2, at a dose rate of 100 μA/cm2. However, once this layer was worn away the wear rate returned sharply to that of unimplanted pure Fe. A high retained N dose has been observed even for a dose rate of 750 μA/cm2 during which the sample reached 280°C.
We report on the nonlinear optical properties of cadmium telluride (CdTe) semiconductor colloidal quantum dots. Transmission electron microscopy measurements revealed that the size of CdTe nanocrystal quantum dots, dependent on the growth reaction time, was ∼2-10 nm or near the exciton Bohr radius. The strong blue-shifts of the CdTe, CdSe and CdS nanocrystal absorption spectra and the atomic-like discrete energy states of exciton indicate an exciton quantum confinement. These are completely different optical properties from the bulk crystals. The energy transition for exciton absorption was assigned as h1→e+, h2→e+, h1+→e-, and h2+→e- for the 1st, 2nd, 3rd and 4th exciton absorption peaks. Z-scan and I-scan nonlinear spectroscopy revealed that the CdTe nanocrystal quantum dot in toluene (∼8 × 10-5 mol/L) has the negative nonlinearity (self-defocusing) with ∼ -1 × 10-13 m2/W and a high nonlinear figure of merit of ∼200. For the optical power self-limiting experiment, the CdTe nanocrystal was almost opaque above ∼0.8 MW/cm2 at the position of z∼6.9 cm.
Ultra-thin epitaxial CoSi2 films formed by Co(3∼5nm)/Ti(1 nm)/Si(100) and Co(3∼5nm)/Si(lnm)/Ti(Inm)/Si are studied. The multilayers are deposited by ion-beam sputtering. Rapid thermal annealing (RTA) is used for silicidation. XRD, RBS, TEM, AFM, four-point probe, I-V and C-V measurements are carried out for characterization. The XRD spectra show the CoSi2 film formed by Co/Ti/Si or Co/Si/Ti/Si solid phase epitaxy has, epitaxial characteristic. XTEM shows that the film is continuous. RBS/Channeling shows that the formed CoSi2 has sharp interface with a minimum channeling yield of Co signal of 40%. AFM shows that the surface of ultra-thin CoSi2 film is smooth with a roughness of nearly 0.7 nm. The Rs∼T relationship shows that the CoSi2 films formed by Co/Si/Ti/Si reaction have the best thermal stability (stable up to 900°C). Those formed by Co/Ti/Si reaction are stable up to 850°C, while those formed by Co/Si reaction are only stable up to 750°C. By fitting the experimental I-V and C-V curves of the epitaxial CoSi2/Si Schottky diodes, barrier heights of around 0.6 eV and close to unity ideality factors are obtained.
Ballistic electron emission microscopy (BEEM) and deep level transient spectroscopy (DLTS) have been used to study the effects of substrate damage introduced by an ion-milling process in PtSi/n-Si Schottky contacts. Argon ions with well-defined energies of 300, 500, 700, 1000, 1500 eV were used to sputter n-type Si substrates in an ion beam sputtering system before metal deposition and silicide formation. Histograms of the PtSi/n-Si Schottky barrier height (SBH) measured by BEEM show that the mean SBH decreases with increasing ion energy, which can be explained as a result of donor-like defects that are introduced by the ion milling treatment. From DLTS measurements, we found direct evidence for the presence of such defects.
The diffusion barrier properties for ultrathin Ru/Ta and Ru/TaN bilayer structure as the copper diffusion barrier are compared. Cu, Ru, Ta and TaN thin films are deposited by using the ion beam sputtering technique. The experimental results show that the thermal stability of the Cu/Ru/Ta or TaN /Si structure is much more improved than that of the Cu/Ru/Si structure without the interlayer. However, the Cu/Ru/TaN/Si shows better thermal stability than the Cu/Ru/Ta/Si structure, which should be attributed to the amorphous nature of the TaN interlayer. The microstructure evolution of the Cu/Ru/Ta (TaN)/Si structure during annealing is discussed. The results show that the Ru/TaN bilayer can be a very promising diffusion barrier in the future seedless Cu interconnect technology.