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The fate of a contracting liquid filament depends on the Ohnesorge number (
), the initial aspect ratio (
) and surface perturbation. Generally, it is believed that there exists a critical aspect ratio
such that longer filaments break up and shorter ones recoil into a single drop. Through computational and experimental studies, we report a transitional regime for filaments with a broad range of intermediate aspect ratios, where there exist multiple
thresholds at which a novel breakup mode alternates with no-break mode. We develop a simple model considering the superposition of capillary waves, which can predict the complicated new phase diagram. In this model, the breakup results from constructive interference between the capillary waves that originate from the ends of the filament.
In the current intensive production system, ruminants are often fed high-grain (HG) diets. However, this feeding pattern often causes rumen metabolic disorders and may further trigger laminitis, the exact mechanism is not clear. This study investigated the effect of HG diet feeding on fermentative and microbial changes in the rumen and on the expression of pro-inflammatory cytokines and matrix metalloproteinases (MMPs) in the lamellar tissue. In all, 12 male goats were fed a hay diet (0% grain; n=6) or an HG diet (56.5% grain; n=6). On day 50 of treatment, samples of blood, rumen content, and lamellar tissue of hooves of goats were collected. The data showed that compared with the hay group, HG-fed goats had lower (P<0.05) rumen pH but higher (P<0.05) total volatile fatty acids and lactate in the rumen and higher (P<0.05) lipopolysaccharide (LPS) levels in the rumen and blood. HG diet feeding altered the composition of rumen bacterial community, and correspondingly, the results suggested that their functions in the HG group were also altered. HG diet feeding increased (P<0.05) the expression of interleukin-1β, interleukin-6, tumour necrosis factor-α and MMP-2 mRNA in the lamellar tissues compared with the hay group. Correlation analysis indicated that the expression of pro-inflammatory cytokines were positively correlated with MMP-2 expression in lamellar tissues. Overall, these results revealed that HG feeding altered the patterns of rumen fermentation and the composition and functions of rumen bacterial community, and lead to higher levels of LPS in the peripheral blood, and further activated the inflammatory response in lamellar tissues, which may progress to the level of laminar damage.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
Mycobacterial diseases are prevalent in cancer and rheumatoid arthritis (RA) patients, especially those receiving tumor necrosis factor-α inhibitor (TNFi). However, the impact of cancer development on the risk of mycobacterial diseases among RA patients is unknown. Data from the Taiwan National Health Insurance Research Database were used to conduct a retrospective study to assess the occurrence of mycobacterial diseases in RA patients developing cancer (cancer-positive), those using TNFi (TNFi-exposure), those with cancer and using TNFi (cancer-TNFi-comb), and those without cancer and not using TNFi (cancer-TNFi-free). Cancer and TNFi exposure were time-dependent, and independent risk factors of mycobacterial diseases were assessed by Cox regression. Among 1344 RA patients diagnosed during 2000–2013, 68 (5·1%) developed cancer before their end points. The incidence rates of mycobacterial diseases in the cancer-positive (n = 56), TNFi-exposure (n = 290), cancer-TNFi-comb (n = 12), and cancer-TNFi-free (n = 986) subgroups were 6·7, 2·0, 7·6, and 1·3 per 1000 person-years, respectively. As compared with the cancer-TNFi-free group, the risk for mycobacterial diseases increased for the TNFi-exposure group (adjusted HR = 3·6, 95% confidence interval (95% CI) 1·1–11·5, P = 0·032) and remained high for cancer-positive (adjusted HR = 14·6, 95% CI 3·3–63·7, P < 0·001) after adjustment. This study suggested that cancer development increased the risk of mycobacterial diseases in RA patients, and risk assessment for this subgroup should be considered.
A ground-based hyperspectral imaging system covering the spectral range of 384–1034 nm was used for Sclerotinia Stem Rot (SSR) detection. Two sample sets of oilseed leaves were collected. Four vegetation indices were extracted and evaluated by analysis of variance (ANOVA) combined with linear discriminant analysis (LDA) for the two sample sets. Discriminant models were built using the 4 vegetation indices. The discriminant results of the two sample sets were good with classification accuracies of the calibration set and the prediction set over 85%. The overall results indicated that vegetation indices calculated from ground-based hyperspectral imaging could be used as reliable and accurate indices for SSR detection.
Elderly individuals with tuberculosis (TB) are more likely to have a non-specific clinical presentation of TB and high mortality. However, factors associated with mortality in elderly TB patients have not been extensively studied. This retrospective cohort study aimed to identify factors associated with death among elderly Taiwanese with TB. All elderly patients with TB from 2006 to 2014 in Taipei, Taiwan, were included in a study. Multiple logistic regression was used to identify the factors associated with death in elderly TB patients. The mean age of the 5011 patients was 79·7 years; 74·1% were men; 32·7% had mortality during the study follow-up period. After controlling for potential confounders, age ⩾75 years (reference: 65–74 years), male sex, end-stage renal disease (ESRD), malignancy, acid-fast bacilli-smear positivity, TB-culture positivity, pleural effusion on chest radiograph and notification by an ordinary ward or intensive care unit were associated with a higher risk of all-cause death; while high school, and university or higher education, cavity on chest radiograph and directly observed therapy were associated with a lower risk of all-cause death. This study found that the proportion of death among elderly patients with TB in Taipei, Taiwan, was high. To improve TB treatment outcomes, future control programmes should particularly target individuals with comorbidities (e.g. ESRD and malignancy) and those with a lower socio-economic status (e.g. not educated).
This paper presents an analytical study on the buckling of cylindrical shells with arbitrary circumferential thickness variations under external pressure. Firstly, based on the thin shell theory and separation of variables, corresponding ordinary differential equations of laterally pressured cylinders are obtained. Secondly, the general asymptotic formula of buckling load, which is in terms of thickness variation parameter up to arbitrary order, is derived by combining the perturbation method and Fourier series expansion. Thirdly, the effects of uniform and circumferential modal thickness variations on the buckling of cylindrical shells under external pressure are investigated, respectively, and the results agree well with those available in literature. Particularly, the buckling load reduction of cylinders with circumferential modal thickness variation obtained by the proposed method coincides with the numerical results presented by Gusic et al. This analytical method is applicable for evaluating the stability of laterally pressured cylindrical shells with arbitrary circumferential thickness variations, once the thickness variation is known.
A structural neuroanatomical change indicating a reduction in brain tissue is a notable feature of schizophrenia. Several pathophysiological processes such as aberrant cortical maturation, progressive tissue loss and compensatory tissue increase could contribute to the structural changes seen in schizophrenia.
We studied cortical thickness using surface-based morphometry in 98 clinically stable patients with schizophrenia and 83 controls. Using a pattern classification approach, we studied whether the features that discriminate patients from controls vary across the different stages of the illness. Using a covariance analysis, we also investigated if concurrent increases accompany decreases in cortical thickness.
Very high levels of accuracy (96.3%), specificity (98.8%) and sensitivity (88%) were noted when classifying patients with <2 years of illness from controls. Within the patient group, reduced thickness was consistently accompanied by increased thickness in distributed brain regions. A pattern of cortical amelioration or normalization (i.e. reduced deviation from controls) was noted with increasing illness duration. While temporo-limbic and fronto-parietal regions showed reduced thickness, the occipital cortex showed increased thickness, especially in those with a long-standing illness.
A compensatory remodelling process might contribute to the cortical thickness variations in different stages of schizophrenia. Subtle cerebral reorganization reflecting the inherent plasticity of brain may occur concomitantly with processes contributing to tissue reduction in adult patients with schizophrenia.
A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m2 in childhood and adolescence and up to 0.2 kg/m2 in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
We compare first-order (refractive) ionospheric effects seen by the MWA with the ionosphere as inferred from GPS data. The first-order ionosphere manifests itself as a bulk position shift of the observed sources across an MWA field of view. These effects can be computed from global ionosphere maps provided by GPS analysis centres, namely the CODE. However, for precision radio astronomy applications, data from local GPS networks needs to be incorporated into ionospheric modelling. For GPS observations, the ionospheric parameters are biased by GPS receiver instrument delays, among other effects, also known as receiver DCBs. The receiver DCBs need to be estimated for any non-CODE GPS station used for ionosphere modelling. In this work, single GPS station-based ionospheric modelling is performed at a time resolution of 10 min. Also the receiver DCBs are estimated for selected Geoscience Australia GPS receivers, located at Murchison Radio Observatory, Yarragadee, Mount Magnet and Wiluna. The ionospheric gradients estimated from GPS are compared with that inferred from MWA. The ionospheric gradients at all the GPS stations show a correlation with the gradients observed with the MWA. The ionosphere estimates obtained using GPS measurements show promise in terms of providing calibration information for the MWA.
In this study, we examine the effect of surface density of disks on chemical evolution of galaxies. We find that, higher surface brightness galaxies on average possess higher gas-phase metallicity compared to lower surface brightness galaxies with the same stellar and gas mass. The surface brightness effect is more significant for low-mass galaxies. Using an analytical model of chemical evolution involving gas outflow and accretion, we find that the surface brightness dependence can be attributed to the strength of inflowing pristine gas. Galaxies with lower surface brightness experience stronger inflow than galaxies with a higher surface brightness of a similar mass.
The issue on the muzzle blast flow with gas-particle mixtures was numerically investigated in this paper. The propellant gas in the cannon was assumed to be gas-particle mixtures consisting of a variety of gaseous species and particles. The model made use of the Eulerian-Eulerican approach, where the particle were modeled as a second fluid with parameters like bulk density, velocity and temperature, interacting with the gas flow. A high-resolution upwind scheme(AUSMPW+) and detailed reaction kinetics model were employed to solve the chemical non-equilibrium Euler equations for gas phase. The Euler equations for particle phase were solved by MacCormack scheme. The particle diameter and the mass fraction of particle were tested to show their effects on the development process of muzzle blast flow with gas-particle mixtures. The distribution of the main flow parameters of both gas and particle were obtained at different time intervals. The results show the evolution of the muzzle blast flow with gas-particle mixtures and demonstrate the effects of key parameter on the flow field of the gas-particle flow. This paper is a significant investigation for understanding the muzzle blast flow with gas-particle mixtures, which can provide valuable reference for the research on the muzzle blast flow.
Nanoparticles (NPs) of Indium Antimonide (InSb) were synthesized using a vapor phase synthesis technique known as Inert Gas Condensation. NPs were directly deposited, at room temperature and under high vacuum, on glass cover slides, TEM grid, 1 inch-square (111) p-type Silicon wafer and Sodium Chloride substrates. XRD study revealed the crystalline behavior of these NPs exhibiting a cubic symmetry with preferred growth direction of (111). The average grain size of the NPs obtained using XRD results and the Debye-Scherrer formula was 25.62 nm. TEM studies showed a bimodal distribution of NPs with average NPs size of 13.70 and 33.20 nm. These values are consistent with the value obtained using XRD. 1:1 composition ratio of In:Sb was confirmed by the Energy Dispersive X-Ray Spectroscopy studies. The band gap of the NPs obtained using Fourier Transform Infrared (FTIR) spectroscopy was 0.413 eV at 300 K, which indicates quantum confinement in the band structure of these NPs.
Important to the development of dye-sensitized solar cells is the longevity and photo-conversion efficiency of the dye. To improve cost effectiveness, dyes of superior thermal and chemical stability are desirable to extend device performance. In this study, we examine a series of peripherally fluorinated Zinc-Phthalocyanines (FxZnPc). Introduction of chemically inert fluorine and isopropyl fluoroalkyl groups on the periphery of the Pc improve the dye stability and allow for tunable photo-physical properties. Additionally, introduction of the bulky isopropyl fluoroalkyl groups help mitigate molecular aggregation in thin films which is known to be detrimental to maintaining the desired photo-physical properties of the surface coating. Using molecular dynamics and first principles modeling, various substituent effects on surface adhesion and aggregation over TiO2 surfaces are characterized for both symmetric and asymmetric substitution.
Carbon dioxide is the major greenhouse gas that is a bi-product of industrial approaches to energy production. Forests and nonagricultural lands act as a natural sink for CO2 removal from the atmosphere; however, the amount of emitted CO2 is significantly larger than the capacity of these natural sinks. This is particularly problematic as two cornerstones of our modern world, electricity generation and transportation, hold the largest share in greenhouse gas (such as CO2) emission. This leads to malignant impacts on the natural environment and human life, such as global warming. The obvious approach to reduce the amount of generated CO2 is to limit the use of fossil fuels. However, coal-fired power plants remain the largest source of electricity generation in 2014 and an equally potent and financially reasonable source is yet to be fully developed. Hence, new systems and strategies are crucial for the remediation of CO2. In this work, we present novel TiO2 nanoparticles, synthesized via a facile solution-phase method, which show a significant visible light absorption. The synthesized nanoparticles can be applied towards photoreduction of CO2 for hydrocarbon solar fuels production. A thorough photoemission spectroscopy analysis outlined the energy structure of the materials which uncovered a sub-bandgap absorption in the visible range due to the presence of intragap states. The origins of intragap states were investigated in greater detail using various characterization techniques. An in-depth chemical composition study of the developed material using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) indicated that the synthesized material is considerably un-doped. Further structural analysis using transmission electron microscopy (TEM) showed that distances between visible lattice fringes are matched with ordered crystalline phases of TiO2. The core emission study using XPS revealed that the oxygen vacancy defects in the structure--i.e. likely due the synthesis--are responsible for intragap states formation. Charge dynamics were investigated using Electron Paramagnetic Resonance (EPR) spectroscopy. EPR spectra were dominated by signals from oxygen-centered surface hole trapping sites with principle g values [2.003, 2.010, 2.023]--i.e. Ti4+ ˗ O2- on anatase. A faint signal was also observed as a function of visible light illumination at 5 K with principle g value of 1.975 that is suggestive of Ti3+ in rutile, a typical product of UV light exposure. In general, this study demonstrates the potential of a relatively inexpensive material for photoreduction of CO2 and generation of solar fuels.
We determined the prevalence and seasonality of infections by Fasciola of goats and bovine species (cattle and water buffalo) in Hubei and Anhui provinces of China. Faecal samples were collected at 2- to 3-month intervals from 200 goats in Hubei province and from 152 bovine species in Anhui province. All faecal samples were examined for the presence of parasites. We determined the nucleotide sequences of the first and second internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA (rDNA) of 39 Fasciola worms from Anhui province. The prevalence of Fasciola infection in goats ranged between 3.5 and 37.0%, with mean eggs per gram (EPG) ranging between 29.0 and 166.0. Prevalence and EPG exhibited downward trends over time with significant differences. The prevalence of Fasciola infection in cattle ranged between 13.3 and 46.2% (mean EPG, 36.4–100.0), and that of water buffalo ranged between 10.3 and 35.4% (mean EPG, 25.0–89.6), with a higher prevalence of infection and EPG from June to October compared with December to March. Analysis of ITS-1 and ITS-2 sequences revealed that F. hepatica and F. gigantica were present in all bovine species of Anhui province and that F. gigantica mainly infected water buffalo. This is the first demonstration of Fasciola infection in Hubei province and detection of F. hepatica and F. gigantica in Anhui province. The present study of Hubei province shows that mass treatment of livestock with closantel sodium injections in April and August/September controlled Fasciola infection effectively.
We report the synthesis of Cu2SnS3 (CTS) nanostructures and its incorporation into an inorganic-organic hybrid device to enhance the photoresponse under AM 1.5 G solar illumination. The nanostructures were structurally and optically characterized. From X-ray diffraction (XRD) and Transmission electron microscopy (TEM) the CTS nanocrystals were found to be tetragonal. Flower like structures of CTS were obtained as seen from Scanning electron microscopy (SEM). A band gap of 1.4 eV was obtained from absorption studies. Two devices have been studied, P3HT: PCBM = 1: 1 and CTS: P3HT: PCBM = 8:1:1. The photocurrent increased from a value of 2.33 mA at dark to 2.5 mA for the P3HT-PCBM blend to 3.36 mA for CTS: P3HT: PCBM = 8:1:1 device. The responsivity, sensitivity, external quantum efficiency and specific detectivity increased from 18.81 mA/W, 1.07, 4.25% and 6.88 × 108 Jones respectively for P3HT:PCBM sample to 189.97 mA/W, 1.44, 42.9% and 6.95 × 109 Jones for CTS: P3HT: PCBM = 8:1:1 sample at 1V bias and 1 Sun illumination intensity. The time dependent photoresponse was stable over different ON-OFF cycles. From the fit to the rise and decay curves, the rise and decay time constants were obtained.
Due to the potential applications to high-efficiency and light-weight solar cells, the growth of CuInGaSe2 (CIGS) nanoparticles is a recent research focus. We have developed a relatively simple solvothermal route to grow high quality CIGS nanoparticles in an autoclave under different temperatures (170 – 280°C). The effect of reaction temperature on the shape of CIGS nanoparticles has been investigated. At lower temperatures, the CIGS particles show plate-like shape. Whereas at higher temperatures, most of them exhibit rod-like feature. The nanoparticle products have been also characterized by field emission scanning electron microscopy and X-ray diffraction techniques.
Nanomedicine is fostering significant advances in the development of platforms for early detection and treatment of diseases. Nanoparticles (NPs) like quantum dots (QDs) exhibit size-dependent optical properties for light-driven technologies, which might become important in bio-imaging, sensing and photo-dynamic therapy (PDT) applications. The present research addresses the synthesis of water-stable Cd-based QDs via a Microwave-Assisted synthesis approach using cadmium sulfate salt, and thioglycolic acid as Cd- and S-precursors, respectively. Selenide ions were available by reductive leaching of metallic Selenium in Sodium bisulfite solution. The size control and the tunability of the optical properties were achieved by a suitable control of the reaction temperature (in the 140°C- 190°C range) and reaction time (10 minutes-40 minutes). X-ray diffraction analyses suggested the development of a CdSe,S face cubic centered structure; the broadening of the diffraction peaks indicated the presence of very small nanocrystals in the samples. The average crystallite size was estimated at 5.50 nm ± 1.17nm and 3.72 nm ± 0.04 nm, for nanoparticles synthesized at 180°C after 40 minutes or 10 minutes of reaction, respectively. HRTEM images confirmed the crystalline nature and the small size of the synthesized nanocrystals. In turn, the exciton was red-shifted from 461nm to 549 nm when the reaction temperature was prolonged from 140°C to 190 °C, suggesting the crystal growth. The corresponding band gap values were approximately 2.2 eV, confirming the quantum confinement effect (bulk value 1.74eV). This red shift was also evidenced in PL measurements where the main emission peak was shifted from 507 nm to 564 nm when the samples were excited at 420 nm. A narrow size-tunable emission also was supported by the full width at half maximum (∼ 45 nm) for the synthesized nanocrystals. The reactive oxygen species generation capability of as-synthesized QDs was also investigated. The correlation between the particle size and the generation of (ROS) by the degradation of methylene blue was evident with a reduction of MB concentration from 10μM to 7.5μM and 6.7μM after 15 minutes of UV irradiation for reaction time of 10 min. and 40 min. respectively. No additional degradation was noticed after 60 minutes of irradiation.