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The charge trap memory capacitors incorporating a stacked charge trapping layer consisting of double layered ZrO2 nanocrystals (NCs) and inserted Al2O3 have been fabricated and investigated. It is observed that the memory capacitor with stacked trapping layer exhibits a hysteresis window as large as 14.3V for 610V sweeping gate voltage range, faster program/erase speed, improved endurance performance, and good data retention characteristics with smaller extrapolated ten years charge loss at room temperature and 125 °C compared to single layered NCs. The special energy band alignment and the introduced additional traps of double layered ZrO2 NCs and inserted Al2O3 change the trapping and loss behavior of charges, and jointly contribute to the remarkable memory characteristics. Therefore, the memory capacitor with a stacked charge trapping layer is a promising candidate in future nonvolatile charge trap memory device design and application. [ABSTRACT FROM AUTHOR]

The charge trap memory capacitors incorporating a stacked charge trapping layer consisting of double layered ZrO2 nanocrystals (NCs) and inserted Al2O3 have been fabricated and investigated. It is observed that the memory capacitor with stacked trapping layer exhibits a hysteresis window as large as 14.3V for 610V sweeping gate voltage range, faster program/erase speed, improved endurance performance, and good data retention characteristics with smaller extrapolated ten years charge loss at room temperature and 125 °C compared to single layered NCs. The special energy band alignment and the introduced additional traps of double layered ZrO2 NCs and inserted Al2O3 change the trapping and loss behavior of charges, and jointly contribute to the remarkable memory characteristics. Therefore, the memory capacitor with a stacked charge trapping layer is a promising candidate in future nonvolatile charge trap memory device design and application. [ABSTRACT FROM AUTHOR]

Side population (SP) cells within tumors are a small fraction of cancer cells with stem-like properties that can be identified by flow cytometry analysis based on their high ability to export certain compounds such as Hoechst 33342 and chemotherapeutic agents. The existence of stem-like SP cells in tumors is considered as a key factor contributing to drug resistance, and presents a major challenge in cancer treatment. Although it has been recognized for some time that tumor tissue niches may significantly affect cancer stem cells (CSCs), the role of key nutrients such as glucose in the microenvironment in affecting stem-like cancer cells and their metabolism largely remains elusive. Here we report that SP cells isolated from human cancer cells exhibit higher glycolytic activity compared to non-SP cells. Glucose in the culture environment exerts a profound effect on SP cells as evidenced by its ability to induce a significant increase in the percentage of SP cells in the overall cancer cell population, and glucose starvation causes a rapid depletion of SP cells. Mechanistically, glucose upregulates the SP fraction through ATP-mediated suppression of AMPK and activation of the Akt pathway, leading to elevated expression of the ATP-dependent efflux pump ABCG2. Importantly, inhibition of glycolysis by 3-BrOP significantly reduces SP cells in vitro and impairs their ability to form tumors in vivo. Our data suggest that glucose is an essential regulator of SP cells mediated by the Akt pathway, and targeting glycolysis may eliminate the drug-resistant SP cells with potentially significant benefits in cancer treatment. [ABSTRACT FROM AUTHOR]

Here we present a systematic study of the effects of pressure on the superconducting and spin/charge density wave (SDW/CDW) transitions of Ba1−xNaxTi2Sb2O (x = 0, 0.10, and 0.15) by means of resistivity measurements. For x = 0 and 0.10, external pressure results in a decease of the SDW/CDW transition temperature Tc; however, no measurable change is observed for the x = 0.15. The pressure effect on the superconducting transition temperature is different for all three samples. For BaTi2Sb2O (x = 0), Tc increases significantly from 1.2 K at zero pressure to ∼2.9 K at 16.1 kbar. The 10% Na-doped sample shows an initial Tc increase up to 4.2 K with pressure which saturates at higher pressure values. For higher Na concentrations (x = 0.15), Tc continuously decreases with increasing pressure. [ABSTRACT FROM AUTHOR]

An efficient system for organogenesis from shoot basal ends was established using an elite clone of Camellia sinensis L. O. Kuntze. In this study, factors that affected the efficiency of shoot regeneration, including explant type (i.e., young leaves, tender stems, or shoots), and plant growth regulators [PGRs; thidiazuron (TDZ), benzyladenine (BA), or indole-3-butyric acid (IBA)] were investigated. Callus induction and subsequent plantlet regeneration were significantly affected by explant type as well as by the level of endogenous and exogenous PGRs. At 0.1 µM TDZ, leaf and stem explants produced callus which failed to regenerate buds during subsequent shoot induction. In contrast, 100% of shoot basal end explants produced callus at all concentrations of TDZ. Shoot basal calli, induced on medium supplemented with 0.1 µM TDZ and 0.49 µM IBA, gave the highest mean percentage of shoot regeneration (67.4%) on medium supplemented with 8.88/µM BA plus 0.49 µM IBA during subsequent shoot induction. Callus initiation on media containing TDZ affected the subsequent regeneration of plantlets; however, the continued presence of TDZ inhibited later regeneration during subsequent sub-cultures. For the C. sinensis clone, 'Longjing 43', the presence of a basal callus during shoot elongation was essential to avoid the deterioration of shoots. Rooting was achieved when the basal cut-end of elongated shoots was dipped in 2.45 mM IBA for 5 min, followed by transfer to PGR-free medium. Elongated shoots treated with 2.45 mM IBA gave the highest rooting percentage (70.8%). Rooted plants could be established in soil with a survival frequency of 60 - 70%. This regeneration system may be considered for the improvement of tea clones through genetic manipulation. [ABSTRACT FROM AUTHOR]

This study investigated the structural and magnetic properties of Mn 3- x Fe x Ga alloys ( x = 0, 0.2, 0.4, 0.6, 0.8, 1) under different heat-treatment conditions. A tetragonal structure was observed in samples that were heat treated at 623 K for three days followed by quenching in ice water. These tetragonal alloys present large coercive fields in the range 0.8-5 kOe and low saturation magnetization, and have great potential for application in spin-transfer torque-based devices. A hexagonal structure was observed in samples subjected to heat treatment at 883 K for three days following quenching in ice water. A moderate decrease in the coercive field has been observed for the hexagonal alloys compared with those with a tetragonal structure. However, the Mn 3- x Fe x Ga alloys with a hexagonal structure exhibit other attractive magnetic properties, including collinear and non-collinear magnetic properties, holding high promise for technological applications. A face-centred-cubic (f.c.c.) structure was observed when subjected to annealing at 1073 K for three days followed by quenching in ice water. In contrast to the tetragonal and hexagonal structures, all f.c.c. alloys exhibit antiferromagnetic behaviour. This versatile material can display a wide range of multi-functionalities attributed to its tuneable crystal structure. This investigation will guide the design of multiple structures of these materials in order to utilise the wide functionalities for practical applications.

In the present study, ten novel microsatellite markers were developed from an enriched-(CA)13 genomic library of Epinephelus akaara. The mean number of alleles per locus was 21.6, with a range of 12 to 33. Observed heterozygosity ranged from 0.767 to 0.967, and expected heterozygosity ranged from 0.831 to 0.975, with mean values of 0.877 and 0.923, respectively. Among the ten loci, three loci deviated from Hardy-Weinberg equilibrium after sequential Bonferroni's correction. These polymorphic microsatellite markers may be useful for studies on the population genetics of E. akaara.

An animal model for infection with Severe acute respiratory syndrome coronavirus (SARSCoV) was evaluated in monkeys Macaca rhesus. The monkeys were inoculated into the trachea with NS-I strain of SARS-CoV and the clinical manifestation of the illness was monitored. The clinical samples collected from infected monkeys were examined by immumnofluorescence assay (IFA), pathological inspection, RTPCR, and by virus isolation. The infected animals demonstrated mild clinical symptoms including fever. Two of the six infected monkeys developed fever (1.5 above the level before challenge) on the day 10 post inoculation (p.i.). Although the severe clinical symptoms or mortality were not observed, the virological and histopathological evidences of the illness were evident. The specimens collected from the infected animals showed the presence of SARS-CoV detected by RT-PCR, IFA, and by virus isolation. From the organs examined postmortem, a major pathological change was observed in the lungs. The walls of the alveoli were thicker, infiltrated with inflammation cells and an exudative fluid was found in the alveolar spaces. In addition, some alveolar spaces showed hyaline membrane lining. The results showed that the monkeys infected with SARS-CoV developed the typical SARS according to clinical, virological, and pathological findings.

The expression of placental hormones in 91 malignant trophoblastic neoplasms was studied immunohistochemically using a panel of antibodies against hCG, human placental lactogen (hPL) and pregnancy-specific 1-glycoprotein (SP). The results indicated that the expression of hCG in invasive moles was weaker than that in choriocarcinoma, but the expression of hPL and SP1 was stronger than those in choriocarcinoma. The expression of hPL and SP1 in the metastatic tumors of invasive moles was weaker than the expression at in the primary tumors, but the secretory capacity of hCG in metastatic choriocarcinomas was stronger than that in the primary neoplasms. In this study, the qualities of expression of the placental hormones in invasive moles and choriocarcinomas corresponded to the degree of tumor malignancy, the biological behaviour and the grading of trophoblastic cell differentiation. We believe that the detection of hCG, hPL and SP1, in malignant trophoblastic neoplasms was of value for establishing tumor diagnosis and typing and for judgement on prognosis.

A combined staining of immunohistochemistry and in situ hybridization has been successfully applied to detect antigen and viral RNA at the same tissue slice from epidemic hemorrhagic fever (EHF) autopsy. Multiple McAb were used to detect EHFV antigen, followed with a digoxigenin-labelling cDNA probe for detecting EHFV RNA respectively. The viral antigen was seen in the cellular cytoplasm and viral RNA was demonstrated within the nuclei. It is emphasized that pretreatment of the section with Lugol's solution and choice of suitable proteolytic enzyme as well as proper temperature and time for the hybridization are the key points for the staining.

The purpose of this study is to examine the alterations in hepatocyte insulin receptors in rats subjected to scald and restrained water immersion stress and the effects of dexamethasone and silybin. In scalded rats, plasma glucose and insulin levels were higher than that of normal rats, suggesting the occurrence of insulin resistance following injury. The maximal binding capacity (Ro) and highest insulin binding rate (Bo/T) of hepatocyte insulin receptors were significantly reduced in rats 72h postscalding, while there was no obvious change in affinity (Ke Kf). The Ro and Bo/T of the restrained water immersion stress rats were also reduced significantly, but the affinity was increased. Dexamethasone significantly enhanced Ro in rats 72h postscalding with significant decrease in affinity (Ke). Silybin significantly enhanced Ro and Bo/T 72h postscalding with no obvious change in affinity. It is suggested that insulin resistance following injury may be a consequence of receptor defect of the target cells, and for disturbance of glucose metabolism following injury, it is not beneficial to use dexamethasone, but silybin may be used with benefit.

The present paper deals with the susceptibility of common laboratory animals, such as mouse, rat, hamster, jird, rabbit and rhesus monkey, to infection with different isolates of Schistosoma japonicum in the mainland of China under laboratory conditions. With the exception of the rat, all the animals under study were permissive hosts for different isolates though their worm recovery rates varied. The mean body length of pair-worms of the Yunnan isolate was considerably smaller than that of the Anhui, Hubei, Guangxi and Sichuan isolates, and the percentage of male specimens with 7 testes in the Yunnan isolate was also significantly less than that in the other 4 isolates. Judging from the egg index (width/length x 100), the eggs of the Sichuan isolate were broad and short in shape, giving a high index; those of Guangxi and Hubei isolates were oblong, giving the lowest index; the other two isolates from Yunnan and Anhui, lay between these two extremes. The mean prepatent periods were longer in mice, hamsters and rhesus monkeys infected with Yunnan and Guangxi isolates, than those with Sichuan isolate. A dendrogram of the 5 isolates of S. japonicum was constructed on the basis of similarity coefficients by means of fuzzy cluster analysis on the biological characters mentioned above. Our results provide evidence of the existence of different strains of S. japonicum in the mainland of China as shown by comparative studies of their characteristics in the final hosts.

In this paper, a computerized numerical systematics was used to analyse the 5 different isolates of Schistosoma japonicum in the mainland of China by means of fuzzy clustering method with 32 quantitative data of each isolate about the morphological and biological characters. A dendrogram of the 5 isolates of S. japonicum was constructed on the basis of similarity coefficients as shown. The phylogenetic relationships revealed by the present study show that the two isolates of Anhui and Hubei get together firstly in one group, then the isolates of both Yunnan and Guangxi gather in another group, while the Sichuan isolate is closely related to the group of Anhui-Hubei isolates, not to the Yunnan ones, although both Sichuan and Yunnan isolates were in the southwest China.