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Human cystic echinococcosis is a widespread, chronic, endemic, helminthic zoonosis caused by larval tapeworms of the species Echinococcus granulosus. At present, there is no rational and effective therapy for patients with echinococcosis. The present study evaluated whether the combination of alkaloids from Sophora moorcroftiana seeds (SMSa2) and Bacillus Calmette–Guérin (BCG) was effective in the treatment of experimental echinococcosis. After 20 weeks of secondary infection with protoscoleces, mice were randomly allocated to five groups and treated for 6 weeks by daily intragastric administration of albendazole (ABZ, 100 mg/kg), SMSa2 (100 mg/kg), BCG (abdominal subcutaneous injection at 5 × 106 CFU), SMSa2 + BCG (100 mg/kg SMSa2 and 5 × 106 CFU BCG) or normal saline (untreated group), respectively. The results indicated a significant reduction in the weight of hydatid cysts in the SMSa2 + BCG group compared with the untreated, SMSa2 and BCG groups. The rate of inhibition of hydatid cyst growth in the SMSa2 + BCG group (76.1%) was obviously increased compared with that in the SMSa2 (25.7%) and BCG (26.6%) groups, respectively. Compared with the untreated control, the SMSa2 + BCG group showed a non-significant increase in serum interleukin-4 (IL-4). Furthermore, the serum levels of interferon-γ (IFN-γ) between the untreated and SMSa2 + BCG groups were not statistically different. Therefore, the combination of alkaloids from S. moorcroftiana seeds and BCG can reduce cyst burden and is an effective therapeutic regimen against echinococcosis.
Feeding a high concentrate (HC) diet is a widely used strategy for supporting high milk yields, yet it may cause certain metabolic disorders. This study aimed to investigate the changes in milk production and hepatic metabolism in goats fed different proportions of concentrate in the diet for 10 weeks. In total, 12 mid-lactating goats were randomly assigned to an HC diet (65% concentrate of dry matter, n=6) or a low concentrate (LC) diet (35% concentrate of dry matter, n=6). Compared with LC, HC goats produced greater amounts of volatile fatty acids and produced more milk and milk lactose, fat and protein (P<0.01). HC goats showed a greater concentration of ATP, NAD, plasma non-esterified fatty acids and hepatic triglycerides than LC goats (P<0.05). Real-time PCR results showed that messenger RNA (mRNA) expression of gluconeogenic genes, namely, glucose-6-phosphatase, pyruvate carboxylase and phosphoenolpyruvate carboxykinase were significantly up-regulated and accompanied greater gluconeogenic enzyme activities in the liver of HC goats. Moreover, the expression of hepatic lipogenic genes including sterol regulatory element-binding protein 1c, fatty acid synthase and diacylglycerol acyltransferase mRNA was also up-regulated by the HC diet (P<0.05). HC goats had greater hepatic phosphorylation of AMP-activated protein kinase than LC (P<0.05). Furthermore, histone-3-lysine-27-acetylation contributed to this elevation of gluconeogenic gene expression. These results indicate that lactating goats fed an HC diet for 10 weeks produced more milk, which was associated with up-regulated gene expression and enzyme activities involved in hepatic gluconeogenesis and lipogenesis.
Maize in Canada is grown mainly in the south-eastern part of the country. No comprehensive studies on Canadian maize yield levels have been done so far to analyse the barriers of obtaining optimal yields associated with cultivar, environmental stress and agronomic management practices. The objective of the current study was to use a modelling approach to analyse the gaps between actual and potential (determined by cultivar, solar radiation and temperature without any other stresses) maize yields in Eastern Canada. The CSM–CERES–Maize model in DSSAT v4·6 was calibrated and evaluated with measured data of seven cultivars under different nitrogen (N) rates across four sites. The model was then used to simulate grain yield levels defined as: yield potential (YP), water-limited (YW, rainfed), and water- and N-limited yields with N rates 80 kg/ha (YW, N-80N) and 160 kg/ha (YW, N-160N). The options were assessed to further increase grain yield by analysing the yield gaps related to water and N deficiencies. The CSM–CERES–Maize model simulated the grain yields in the experiments well with normalized root-mean-squared errors <0·20. The model was able to capture yield variations associated with varying N rates, cultivar, soil type and inter-annual climate variability. The seven calibrated cultivars used in the experiments were divided into three grades according to their simulated YP: low, medium and high. The simulation results for the 30-year period from 1981 to 2010 showed that the average YP was 15 000 kg/ha for cultivars with high yield potential. The YP is generally about 6000 kg/ha greater than the actual yield (YA) at each experimental site in Eastern Canada. Two-thirds of this gap between YP and YA is probably associated with water stress, as a gap of approximately 4000 kg/ha between the YW and the YP was simulated. This gap may be reduced through crop management, such as introducing irrigation to improve the distribution of available water during the growing season. The simulated yields indicated a gap of about 3000 and 1000 kg/ha between YW and YW,N-80N for cultivars with high YP and low YP, respectively. The gap between YW and YW,N-160N decreased to <2000 kg/ha for high Yp cultivars with little difference for the low Yp cultivars. The different yield gaps among cultivars suggest that cultivars with high YP require high N rates but cultivars with low YP may need only low N rates.
Eating raw pork and/or liver is a custom of the Bai ethnic group in China. Most people living in Dali Bai Autonomous Prefecture, Yunnan Province, southwestern China are of Bai ethnicity. Little is known of the seroprevalence of Toxoplasma gondii in Bai and Han ethnic populations in this region. In the present survey, a total of 555 and 595 blood samples were obtained from Bai and Han ethnic groups in Dali urban and rural areas, respectively. Enzyme-linked immunosorbent assay was performed to examine T. gondii IgG antibodies. Total positive rate of anti-T. gondii IgG in Bai and Han groups in this region was 21·6% (248/1150). The total seroprevalence of T. gondii was significantly higher in the Bai ethnic group (32·3%, 179/555) than in the Han ethnic group (11·6%, 69/595) (P < 0·01). The results of statistical analysis indicated that there was no significant difference between cat feeding/non-cat feeding groups in the Bai ethnic group, the most important risk factor was consumption of raw pork and/or liver for the Bai group, but feeding a cat may be the main route of T. gondii infection for the Han group. Therefore, it is essential to implement integrated strategies to prevent and control T. gondii infection in this unique region of the world.
Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?
Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus.
Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.
MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.
Flexible surface acoustic wave (SAW) based temperature and humidity sensors were fabricated and characterized. ZnO piezoelectric films were deposited on polyimide substrates by DC magnetron sputtering. ZnO films possess (0002) crystal orientation with large grain sizes of 50∼70 nm. SAW devices showed two wave modes, namely the Rayleigh and Lamb modes, with the frequencies at fR ∼132MHz and fL∼427MHz respectively for a wavelength of 12 μm device. The two resonant frequencies have a temperature coefficient of frequency (TCF) of −423ppm/K and −258ppm/K for the Rayleigh and Lamb waves, respectively. The SAW sensors exhibited a good repeatability in responding to cyclic change of humidity. The responses of the sensors increase with the increase in humidity, and the sensitivity increases with the decrease in wavelength. A high sensitivity of 34.7 kHz/10%RH has been obtained from a SAW device without any surface treatment, demonstrated that the flexible SAW humidity sensors are very promising for application in flexible sensors and microsystems.
Flexible electronics and microsystems are an emerging technology with a tremedous impact to the future electronics and information technology and widespread applications. Various devices and microsystems have been developed. Surface acoustic wave (SAW) devices are a type of essential device for electronics, microsensors and microsystems; however there is no activity on the development of flexible SAW devices yet. This paper reports the development of flexible SAW devices on cheap, bendable and disposable plastic films. Flexible SAW devices with resonant frequency of 198.1 MHz and 447 MHz for the Rayleigh and Lamb waves respectively have been obtained with a large transmission signal up to 18dB. The flexible SAW devices have also demonstrated their ability for acoustic streaming with a velocity up to 3.4 cm/s and for particle concentration. The results have clearly demonstrated that the flexible SAW devices have great potential for applications in electronics and microsystems.
We present our recent efforts to unveil and understand the origin of massive stars outside the three massive star clusters in the Galactic center. From our Hubble/NICMOS survey of the Galactic center, we have identified 180 Paschen-α emitting sources, most of which should be evolved massive stars with strong optically thin stellar winds. Recently, we obtained Gemini GNIRS/NIFS H- and K-band spectra of eight massive stars near the Arches cluster. From their radial velocities, ages and masses, we suggest that in our sample, two stars are previous members of the Arches cluster, while other two stars embedded in the H1/H2 Hii regions formed in-situ.
The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?
Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.
The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.
MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.
Previous studies support Beck's cognitive model of vulnerability to depression. However, the relationship between his cognitive triad and other clinical features and risk factors among those with major depression (MD) has rarely been systematically studied.
The three key cognitive symptoms of worthlessness, hopelessness and helplessness were assessed during their lifetime worst episode in 1970 Han Chinese women with recurrent MD. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression.
Compared to patients who did not endorse the cognitive trio, those who did had a greater number of DSM-IV A criteria, more individual depressive symptoms, an earlier age at onset, a greater number of episodes, and were more likely to meet diagnostic criteria for melancholia, postnatal depression, dysthymia and anxiety disorders. Hopelessness was highly related to all the suicidal symptomatology, with ORs ranging from 5.92 to 6.51. Neuroticism, stressful life events (SLEs) and a protective parental rearing style were associated with these cognitive symptoms.
During the worst episode of MD in Han Chinese women, the endorsement of the cognitive trio was associated with a worse course of depression and an increased risk of suicide. Individuals with high levels of neuroticism, many SLEs and high parental protectiveness were at increased risk for these cognitive depressive symptoms. As in Western populations, symptoms of the cognitive trio appear to play a central role in the psychopathology of MD in Chinese women.
The allelochemicals 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) and 6-methoxy-benzoxazolin-2-one (MBOA) in wheat are considered to have a role in plant defense against weeds. This study explored the effect of proximity to two weeds, wild oat and flixweed, on DIMBOA/MBOA production in wheat seedlings under hydroponic culture to identify whether the breeding of modern wheat varieties with higher concentrations of these compounds could ensure plant-mediated weed control. MBOA was detected and was noted to exert a significant response; its exudation by some wheat seedlings was significantly increased irrespective of whether the roots were in contact with or separate from those of the weeds. The weeds were a source of biotic stress to wheat when grown in proximity to it, and the stress resulted in production of higher levels of MBOA in wheat seedlings, although the concentration varied with the wheat cultivar. Therefore, the synthesis and exudation of DIMBOA/MBOA in wheat seedlings appears to be an active metabolic process influenced by the environment, particularly the presence of weeds.
With RXTE data ranging from 1997 August to 1998 May, we detected 8 type I X-ray bursts from the atoll source 4U 1735–44. The bursts are present at all the branches, and most occur at an inferred low mass accretion rate. We find no correlation between the peak flux of the bursts and the mass accretion rate. The results are different from that of 4U 1728-34, whose bursts' peak flux are anti-correlated with the mass accretion rate.
The magnetic reconnection (MR) configuration was constructed by using two approaching laser-produced plasma bubbles. The characteristics of the MR current sheet were investigated. The driving energy of the laser pulse affects the type of the current sheet. The experiments present “Y-type” and “X-type” current sheets for larger and smaller driving energy, respectively. The energetic electrons were found to be well-collimated. The formation and ejection of plasmoid from the “Y-type” current sheet was expected to enhance the number of accelerated electrons.
Excitation of the geodesic acoustic mode continuum by drift wave turbulence is studied using the wave kinetic approach. For a model profile of weak non-uniform ion temperature, the forms of growth rate and radial structure of geodesic acoustic modes are obtained analytically. The growth rate is analyzed for several conditions for present-day tokamaks and compared with that for uniform ion temperature, as well as that given by the coherent mode approach for non-uniform ion temperature.
The laser wakefield structure in a magnetized underdense plasma is studied analytically and numerically. Because of the DC magnetic field perpendicular to the laser propagation direction, an electromagnetic component appears in addition to the normal electrostatic component. This electromagnetic component can transmit partially into vacuum at the plasma–vacuum boundary as shown by particle-in-cell simulation. It is found that the emission has components both at the fundamental plasma frequency and its harmonics if the wakefield is driven at a high amplitude. Comparing with the emission at the plasma frequency, the harmonic emission depends weakly upon the density profile at plasma–vacuum boundary and it can pass through the boundary almost without energy loss, providing a new method for the diagnostic of wakefields.
Angiostrongylus cantonensis (A. cantonensis) infection causes eosinophilic meningitis in humans. Eosinophilia and a Th2-type immune response are the crucial immune mechanisms for eosinophilic meningitis. CD4+CD25+ regulatory T cells (Treg) are involved in the pathogenesis of A. cantonensis. Diammonium glycyrrhizinate (DG) is a compound related to glycyrrhizin (GL), a triterpene glycoside extracted from liquorice root. We investigated the curative effects and probable mechanisms of therapy involving a combination of albendazole and DG in BALB/c mice infected with A. cantonensis, and compared these with therapy involving albendazole and dexamethasone. We analysed survival time, body weight, signs, eosinophil numbers, immunoglobulin E (IgE), interleukin-5 (IL-5), and eotaxin concentrations, numbers and Foxp3 expression of CD4+CD25+ Treg, worm recovery and histopathology. The present results demonstrated that the combination of albendazole and DG could increase survival time more efficiently and relieve neurological dysfunction; decrease weight loss, eosinophil numbers, concentrations of IgE, IL-5 and eotaxin, the number and expression of Foxp3 of CD4+CD25+ Treg; and improve worm recovery and histopathology changes in treated animals, compared with the combination of albendazole and dexamethasone. The observations presented here suggest that the albendazole and dexamethasone combination could be replaced by the combination of albendazole and DG.
The presence of a superstructure is identified to play a key role for the modifications in both superconductivity and structure transitions in the Mg1-xAlxB2 system. This superstructure occurs along the c-axis direction, and can be well interpreted by Al-layer ordering. The optimal composition of the superstructure phase is MgAlB4, a superconductor with Tc ∼12K. Raman spectrum of MgAlB4 gives rise to a sharp peak at around 941cm−1. Brief diagrams illustrating the superconductivity and structural features of Mg1-xAlxB2 (0≤x≤1) materials are presented.
Monochromatized synchrotron radiation has been employed as the excitation source for soft x-ray emission spectroscopy. In the present paper changes in the emission spectra that occur as the excitation energy is varied near the core-absorption threshold are discussed. In the case of crystalline silicon, strong variations are seen in the L2,3 emission for excitation energies up to 30 eV above threshold. These variations are shown to be dependent on the crystalline order of the material and can be interpreted in terms of restrictions on the crystal momentum that arise in an inelastic scattering description of the combined absorption and emission. On the other hand this description is less relevant to the excitation-energy dependence of ionic insulators, in which strong phonon coupling removes these restrictions on crystal momentum. In the insulators B2O3 and BN strong variations in the emission are observed at threshold, upon creation of a core exciton: the exciton affects the emission through its influence on the phonon coupling as well as on the initial and final-state screening.
In this paper, molecular beam epitaxial growth of Ni2MnGa single crystal layers on GaAs (001) using a NiGa interlayer is reported. X-ray diffraction and transmission electron microscopy confirmed an epitaxial relationship of Ni2MnGa “010] // GaAs   and a tetragonal structure of the film (a = b = 5.79 Å, c = 6.07 Å). Magnetic measurements using vibrating sample and superconducting quantum interference device magnetometers revealed an in-plane magnetization of ∼200 emu/cm3at room temperature and a Curie temperature of ∼350 K. The martensitic phase transformation was observed to occur at ∼250 K
This paper reviews of some of the progress made in the development of ZnO-based light emitting diodes (LEDs). n-ZnO/p-AlGaN-based heterostructures have been successfully for the fabrication of UV emitting LEDs that have operated at temperatures up to 650K, suggesting an excitonic origin for the optical transitions. RF-plasma-assisted molecular beam epitaxy has been used to grow epitaxial CdxZn1-xO films on GaN/sapphire structure. These films have a single-crystal wurtzite structure as demonstrated by structural and compositional analysis. High quality CdxZn1-xO films were grown with up to x=0.78 mole fraction as determined by RBS and SIMS techniques. Optical emission ranging from purple (Cd0.05Zn0.95O) to yellow (Cd0.29Zn0.71O) was observed. Compositional fluctuations in a Cd0.16Zn0.84O films were not detected by spatially resolved CL measurements, although intensity fluctuation with features of ∼0.5 μm diameter were seen on the intensity maps. Time resolved photoluminescence shows multi-exponential decay with 21 psec. and 49±3 psec. lifetimes, suggesting that composition micro-fluctuations may be present in Cd0.16Zn0.84O film.