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Sintering characteristics and microwave dielectric properties of Mg4Ta2O9-5wt% B2O3 ceramics were investigated. With the sintering temperature increasing in the range of 1100C-1350C, the apparent density, and values increased firstly and then saturated at 1250C with excellent microwave properties: , GHz and ppm/C. Compared to the pure MT ceramics, the B2O3 additives effectively decreased the sintering temperature of MT ceramics and had no detrimental effect on the properties of the MT ceramics due to the liquid phase effect. [ABSTRACT FROM AUTHOR]

Corundum structured Mg4Nb2O9 dielectric ceramics with the excess of MgO were prepared by the sol-gel process and microwave dielectric properties were investigated with the excess of MgO. First, according to the stoichiometric ratio of Mg4Nb2O9 phase formation was studied by means of XRD analysis by adjusting the ratio of Mg/Nb and the ratio was ranging from 0·5 to 2·4. Subsequently, based on phase formation microwave dielectric properties of Mg4Nb2O9 ceramics as a function of ratio of Mg/Nb were obtained depending on phase change. The results showed that when the ratio of Mg/Nb was 2·1, pure phase of Mg4Nb2O9 ceramics could be obtained at 1275°C with excellent microwave dielectric properties of εr = 12·5, Qƒ = 224,000 GHz, τƒ = −42·8 ppm/°C. [ABSTRACT FROM AUTHOR]

Analysis of Permian-Triassic brachiopod diversity and body size changes from different water depths spanning the continental shelf to basinal facies in South China provides insights into the process of environmental deterioration. Comparison of the temporal changes of brachiopod diversity between deepwater and shallow-water facies demonstrates that deepwater brachiopods disappeared earlier than shallow-water brachiopods. This indicates that high environmental stress commenced first in deepwater settings and later extended to shallow waters. This environmental stress is attributed to major volcanic eruptions, which first led to formation of a stratified ocean and a chemocline in the outer shelf and deeper water environments, causing the disappearance of deep marine benthos including brachiopods. The chemocline then rapidly migrated upward and extended to shallow waters, causing widespread mass extinction of shallow marine benthos. We predict that the spatial and temporal patterns of earlier onset of disappearance/extinction and ecological crisis in deeper water ecosystems will be recorded during other episodes of rapid global warming. [ABSTRACT FROM AUTHOR]

Boroaluminosilicate glasses containing were prepared by the normal quenching method. The glass transition temperatures (Tg) were measured by differential scanning calorimetry (DSC). The structural role of RO was investigated by nuclear magnetic resonance (NMR). Chemical durability was evaluated by weight losses of glass samples after immersion in HC1 solution. High resolution scanning electron microscopy (HR-SEM) was used to examine the surface micrographs of corroded glass samples. The dielectric constant and tangent loss were measured in the frequency range 10-106 Hz. The results revealed that chemical durability and dielectric properties increased with increasing content. [ABSTRACT FROM AUTHOR]

Nanosized and highly reactive Mg4Ta2O9 were successfully synthesized by aqueous sol-gel method compared with conventional solid-state method. Ta-Mg-citric acid solution was first formed and then evaporated resulting in a dry gel for calcination in the temperature ranging from 600°C to 800°C for crystallization in oxygen atmosphere. The crystallization process from the gel to crystalline Mg4Ta2O9 was identified by thermal analysis and phase evolution of powders was studied using X-ray diffraction (XRD) technique during calcinations. Particle size and morphology were examined by transmission electron microscopy (TEM) and high resolution scanning electron microscopy (HR-SEM). The results revealed that sol-gel process showed great advantages over conventional solid-state method and Mg4Ta2O9 nanopowders with the size of 20-30 nm were obtained at 800°C. [ABSTRACT FROM AUTHOR]

The article explores the changes in long term tropical rainfall from 1979 to 2003 by analyzing rainfall data sets from the Global Precipitation Climatology Project (GPCP) and the Climate Prediction Center Merged Analysis Product (CMAP). Analysis of two data sets reveal a significant shift in the probability distribution function of tropical rainfall during the said period. The shift features a positive trend in the occurrence of heavy and light tropical rain, then a negative trend in moderate tropic rain. Moreover, the authors discuss the relations between the trends and changes in rainfall characteristics during the given period.

BALB/c mice are widely used in genetic, tumour and immunological studies. However, the mice demonstrate a lower reproduction rate, low fertility and small litters, because of their highly genetic homozygoisty . Based on in vitro fertilization (IVF), a routine technique for biomedical studies, it is worth to evaluate the effects to BALB/c mice on IVF efficiency. In order to test the genetic factor affecting the IVF efficiency of BALB/c, four reciprocal IVF tests of BALB/cByJ and FVB/NCrl mice were performed. The results showed that the average fertility of IVF sponsored by FVB/NCrl spermatozoa was 69.6%, but only 12.1% was obtained from BALB/cByJ strain. Effect of glucose contained in the culture medium to the IVF efficiency of BALB/cByJ was also evaluated. The results showed that the fertility of BALB/cByJ spermatozoa incubated with 0, 2.7, 5.5, 11.1 and 22.2 m m of glucose in the TYH medium were 6.8, 9.9, 13.9, 32.7 and 22.2%, respectively . It is showed that IVF efficiency of BALB/cByJ spermatozoa could be improved depending on the concentration of glucose in the IVF medium. According to the results, it is beleived that lower IVF of BALB/cByJ mice might be due to the genetic defect in spermatozoa and increasing glucose in the IVF medium which significantly affect the IVF efficiency of BALB/cByl via activating the spermatozoa. [ABSTRACT FROM AUTHOR]

The Rayleigh–Ritz variational method is carried out with a multiconfiguration-interaction wave function and restricted variational method to obtain the relativistic energies of the 1s[sup 2]2s2p [sup 1]P[sup o], 1s[sup 2]2s2p [sup 3]P[sup o], and 1s[sup 2]2p[sup 2][sup 3]P states for the beryllium-like isoelectronic sequence (Z=4–10), including the mass polarization and relativistic corrections. The oscillator strengths and transition rates are also calculated. The results are compared with other theoretical and experimental data in the literature. The hyperfine structure of the low-lying excited states for this system is also explored. [ABSTRACT FROM AUTHOR]

Using global rainfall and sea surface temperature (SST) data for the past two decades (1979–98), the covariability of the Asian summer monsoon (ASM) and El Niño–Southern Oscillation (ENSO) was investigated. The findings suggest three recurring rainfall–SST coupled modes. Characterized by a pronounced biennial variability, the first mode is associated with generally depressed rainfall over the western Pacific and the “Maritime Continent,” stemming from the eastward shift of the Walker circulation during the growth phase of El Niño. The associated SST pattern consists of an east–west SST seesaw across the Pacific and another seesaw with opposite polarity over the Indian Ocean. The second mode is associated with a growing La Niña, comprising mixed, regional, and basin-scale rainfall and SST variability with abnormally warm water in the vicinity of the Maritime Continent and western Pacific. It possesses a pronounced low-level west Pacific anticyclone (WPA) near the Philippines and exhibits large subseasonal-scale variability. The third mode is associated with regional coupled ocean–atmosphere processes in the ASM region, having spatial and temporal variabilities that suggest extratropical linkages and interhemispheric interactions occurring on decadal timescales. Results indicate the importance of regional processes in affecting ASM rainfall variability. On the average, and over the ASM region as a whole, ENSO-related basin-scale SSTs can account for about 30% of the variability, and regional processes can account for an additional 20%. In individual years and over subregions, the percentages can be much higher or lower. In addition to the shift in the Walker circulation, it is found that the regional excitation of the WPA is important in determining the rainfall variability over south Asia and east Asia. Based on the results, a hypothesis is proposed that anomalous wind forcings derived from the... [ABSTRACT FROM AUTHOR]

Offers a look at a field experiment for the evaluation of energy and water cycles of the Asian monsoon region, called the South China Sea Monsoon Experiment (SCSMEX), which was launched in May 1998. Aim of SCSMEX; What is represented by the South China Sea (SCS) monsoon; Evolution of the May 1997 SCS monsoon; Information on SCSMEX.

The article presents a case study of a 79-year-old woman with unusual lymphangiosarcoma in the scalp. The patient had a mass that was thought clinically as sebaceous cyst and was surgically excised with radiotherapy, but she died after two years. Histological findings describe a misdiagnosed angiosarcomas masquerading as cutaneous follicle centre cell lymphoma and pseudolymphoma, rather than an anaplastic large cell lymphoma based on morphology.

Isochrysis galbana is a species of Haptophyta, which can synthesize unsaturated fatty acids such as EPA and DHA, and rich content in vitamins, polysaccharides, sterols and carotenoids. Therefore, it is one of the valuable sources for human and animal nutrition. Hydrogen peroxide (H2O2) is a reactive oxygen species and the simplest peroxide. Hydrogen peroxide can damage cell DNA and is often used in in vitro studies. In this study, the fatty acid of Isochrysis galbana was extracted and added into H2O2 damage-induced mouse hepatocytes cell line BNL CL.2 in different conditions. To determine the adipogenesis inhibition effect of marine microalgae fatty acid, we analyzed cell activity and antioxidant activity by MTT and DCFDA, and analyzed the expression of proinflammatory cytokines, apoptosis genes, adipogenic transcription genes by RT-PCR. The results showed Isochrysis galbana fatty acid extract can effectively reduce ROS production, protect cells from H2O2 damage. The downward trend of Casp3, and the significantly reduced Fabp4 expression showed Isochrysis galbana fatty acid extract has the effect of restraining apoptosis and lipid accumulation in vitro. [ABSTRACT FROM AUTHOR]

Lameness, mastitis, and reproductive disorder are three major diseases occurring in Taiwanese dairy cows. The hoof disease not only leads to lameness in cows but also harms lactation ability, reproductive efficiency, animal welfare, and the shortage of service life. Nevertheless, most Taiwanese dairy farms focus on therapeutic hoof trimming instead of preventive hoof caring to control the hoof problem. Therefore, the purpose of the study was to analyze different types of hoof lesions to schedule better intervals for preventive hoof trimming. The results indicated that the incidence rate of lesions, including sole ulcer, sole hemorrhage, thin sole, interdigital dermatitis/digital dermatitis, and white line disease were 21%, 17%, 19%, 19%, and 6%, respectively. In the trial, the result showed that the incidence rate of sole ulcer and sole hemorrhage in cows having done hoof caring two months before the expected calving date was 10% and 30%, yet those incidence rates were similar in therapeutic hoof trimming and preventive hoof trimming of the cows 60-70 days after calving. In conclusion, the types of hoof lesions mainly happening in commercial dairy farms are sole ulcer, thin sole, interdigital dermatitis, and digital dermatitis; besides, from the review, the postpartum hoof trimming intervals should be shortened to attain the desired result of preventive hoof trimming. [ABSTRACT FROM AUTHOR]

The double InGaAs/InAs channel structure is designed to improve DC and RF characteristics of InP-based HEMT, which is studied by the numerical simulation. The saturated channel current, transconductance, subthreshold slope, drain induced barrier lowering, and frequency characteristics are analyzed. A comparison is done between the device with the double InGaAs/InAs channel and InGaAs channel. By using double InGaAs/InAs channel, maximum transconductance of 1019.7 mS/mm is achieved, and the lower value of subthreshold slope and drain induced barrier lowering is also obtained. The excellent performance of device with double InGaAs/InAs channel structure is mainly due to the enhanced confinement of the electrons in the channel region. In addition, the maximum oscillation frequency of 758.7 GHz is obtained with the double InGaAs/InAs channel structure. These results indicate that InP-based HEMT with double InGaAs/InAs channel structure is a promising candidate for high frequency application. [ABSTRACT FROM AUTHOR]

We present the case of a 57-year-old para 6 who was referred by a general practitioner to our tertiary level hospital with a pelvic abdominal mass as well as valvular heart disease and right heart failure. She had a subtotal hysterectomy, bilateral Salpingooophorectomy and an infracolic omentectomy. The histology revealed a primary ovarian carcinoid. She was free of carcinoid syndrome-related symptoms for a period of ten years. After this period of time, she unfortunately passed away from COVID-19 related complications (in July 2020). [ABSTRACT FROM AUTHOR]