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Complex conductivity of FeSe0.5Te0.5 superconducting films has been investigated using backward-wave-oscillator spectroscopy in the terahertz frequency range. The normal state conductivity corresponds well to the lowfrequency limit of a Drude metal. In the superconducting state, the real part of the complex conductivity is not completely suppressed, indicating the existence of a strongly anisotropic gap. Weak features in the conductivity are consistent with the superconducting gap value close to 12 cm-1(1.5 meV). The experimental results are discussed within the framework of a two-gap model based on the s± symmetry of the order parameter. [ABSTRACT FROM AUTHOR]

Soil loss from unpaved rural roads contributes largely to watershed sediment yield. A road erosion model is therefore urgently needed to evaluate road erosion production. Field flow simulation experiments were conducted on unpaved loess roads under five flow rates and three slope gradients in order to quantify road surface hydraulics and develop soil detachment prediction models. The results showed that flow velocity was highly related to flow rate but generally independent of slope gradient. The hydraulic roughness of the road surface was much less titan that of cropland and was influenced significantly by relatively intensive erosion on steep slopes. Easily obtainable parameters such as flow rate and slope gradient could be used to estimate soil detachment accurately. Furthermore, power functions of chosen hydraulic parameters, (i.e., shear stress, stream power, and unit stream power) could be used to predict detachment rates. Among these parameters, flow shear stress was the best predictor. A detachment prediction model similar to that used in the WEPP model was proposed. Corresponding to the excess shear stress model in WEPP, loess road surface soil erodibility is 0.0066 s m-1 and critical shear stress is 3.25 Pa. [ABSTRACT FROM AUTHOR]

Underdoped electron-doped La2-xCexCuO4 (x=0.06-0.09) thin films were successfully grown and investigated for the transport properties in ab-plane. It was found that the in-plane resistivity ρab shows a semiconductor behavior when x=0.06, with increasing the Ce concentration to the optimal doping level, it changes to the two dimensional Fermi-liquid behavior. In the films with x≥0.08, a Kondo effect like scattering is observed in the low temperature range. [ABSTRACT FROM AUTHOR]

YBa2Cu3O7-δ/La0.67Ca0.33MnO3 heterostructures were fabricated and patterned to study the interfacial transport between a ferromagnet (FM) and a dx2-y2-wave superconductor. Zero bias conductance peaks (ZBCPs) in the differential conductance spectra were observed in the interface where a YBCO layer shows a mixed c- and a-axis orientation. In contrast, a zero bias conductance dip (ZBCD) was observed in the interface with a purely c-axis oriented YBCO layer. [ABSTRACT FROM AUTHOR]

High quality epitaxial thin films of FeSe1-xTe_x (x=0–1) have been successfully fabricated. Their superconducting transition temperatures are around 8–13 K. Microwave properties of a film (x=0.7) was studied by a sapphire dielectric cavity at 9.315 GHz. The cavity, which has a quality factor of 45000 in room temperature with TE011-mode, is specially designed for the measurement of small samples with the sapphire cylinder having a small hole in the center. Thin film samples with dimension of 1–2 mm can be put in the middle of the hole, supported by a very thin sapphire rod. The cavity is sealed in a vacuum chamber soaked in the liquid ^4He and the temperature of the thin sapphire rod (hence the sample) can be controlled from 1.6 K to 60 K with a stability about \pm1 mK. Temperature dependence of transmission response and Q-factors were measured by a network analyser (Agilent N5230C). The results showed a clear signature of multi-gap superconductivity. No evidences of existence of node in the energy gap were found as the normalized change in the surface reactance and the corresponding normalized change in the in-plane penetration depth have flat dependence at low temperatures. [ABSTRACT FROM AUTHOR]

Ferroelectric K0.5Na0.5NbO3 (KNN) thin film was epitaxially grown on La0.67Sr0.33MnO3 (LSMO) buffered LaAlO3 substrate by pulse laser deposition. The crystallographic structure of KNN/LSMO was confirmed by x-ray diffraction. Interestingly, a dielectric relaxor feature was found in the temperature range 200–350 °C. The activation energies for relaxation and conduction of the films were found to be 1.87 and 0.63–0.71 eV, respectively. The mechanism for dielectric relaxation in KNN/LSMO structure was discussed under a thermally activated process. The remnant polarization and coercive field of the films were 21.3 μC/cm2 and 91 kV/cm, respectively. [ABSTRACT FROM AUTHOR]

The exchange bias effect has been observed in the superlattices consisting of ferromagnetic La0.67Sr0.33MnO3 and nonmagnetic insulating SrTiO3 layers. It is found that the exchange field shows an oscillatory decay with a period of ∼12 unit cells and approaches to a constant value of -100 Oe when the SrTiO3 thickness is increased. The tunneling current also displays a nonmonotonic decrease with the SrTiO3 thickness. These observations can be discussed on the basis of the interlayer exchange coupling between La0.67Sr0.33MnO3 layers via the spin-polarized electrons tunneling across the SrTiO3 spacers. [ABSTRACT FROM AUTHOR]

Epitaxial Ba0.15Zr0.85TiO3 (BZT) ferroelectric thin films with (001), (011), and (111) orientations were, respectively, grown on La0.67Sr0.33MnO3 (LSMO) buffered LaAlO3 substrates by pulsed laser deposition method. The dc electric-field dependence of permittivity and dielectric loss of (001)-, (011)-, and (111)-oriented BZT/LSMO heterostructures obeys the Johnson formula, and the ac electric-field dependence of that obeys the Rayleigh law under the subswitching field region. The anisotropic dielectric properties are attributed to the higher mobility of the charge carriers, the concentration of mobile interfacial domain walls, and boundaries in the (111)-oriental films than in the (110)- and (100)-oriented films. [ABSTRACT FROM AUTHOR]

We use magnetism and specific heat measurements to investigate the hexagonal Mn-rich YMnO3. It is found that upon cooling from a high temperature, the compound first orders antiferromagnetically at TN∼72 K and then undergoes a re-entrant spin glass (RSG) transition at TSG∼42 K. This RSG behavior results from the competition between the ferromagnetic interaction and the antiferromagnetic interaction, which is related to the intrinsic geometric magnetic frustration in this system. [ABSTRACT FROM AUTHOR]

Studies the use of allogeneic peripheral blood stem cell transplantation in the treatment of leukemia in China. Subjects and procedures; Results; Discussion.

A ferroelectric and colossal-magnetoresistant material with a Ba0.5Sr0.5TiO3 (BST)/La0.67Sr0.33 MnO3 (LSMO) heterostructure was deposited epitaxially on (001) LaAlO3 substrates through pulsed laser deposition. Measurements of the magnetic and ferroelectric properties show no obvious degradation of the LSMO layer after BST film deposition. For the BST film, as the temperature decreases from 300 to 20 K, both the remanent polarization and the coercive field increase monotonously up to 5.7 µC cm−2 and 63.7 kV cm−1, respectively. Meanwhile, the temperature dependence of the spontaneous polarization shows a second-order ferroelectric phase transition, and the Curie temperature is estimated to be about 220 K. Furthermore, in the temperature range from 20 to 300 K, the dielectric constant (E = 0) and the dielectric tunability (E = 200 kV cm−1) exhibit similar temperature dependences, and show maximum values of 1252 and 45.3% at 200 K, respectively. [ABSTRACT FROM AUTHOR]

Single-phased, single-oriented thin films of Mn-doped ZnAs-based diluted magnetic semiconductor (DMS) Ba1-xKx(Zn1-yMny)2As2 (x = 0.03, 0.08; y = 0.15) have been deposited on Si, SrTiO3, LaAlO3, (La,Sr)(Al,Ta)O3, and MgAl2O4 substrates, respectively. Utilizing a combined synthesis and characterization system excluding the air and further optimizing the deposition parameters, high-quality thin films could be obtained and be measured showing that they can keep inactive-in-air up to more than 90 hours characterized by electrical transport measurements. In comparison with films of x = 0.03 which possess relatively higher resistivity, weaker magnetic performances, and larger energy gap, thin films of x = 0.08 show better electrical and magnetic performances. Strong magnetic anisotropy was found in films of x = 0.08 grown on (La,Sr)(Al,Ta)O3 substrate with their magnetic polarization aligned almost solely on the film growth direction. [ABSTRACT FROM AUTHOR]

We use magnetism and specific heat measurements to investigate the hexagonal Mn-rich YMnO3. It is found that upon cooling from a high temperature, the compound first orders antiferromagnetically at TN∼72 K and then undergoes a re-entrant spin glass (RSG) transition at TSG∼42 K. This RSG behavior results from the competition between the ferromagnetic interaction and the antiferromagnetic interaction, which is related to the intrinsic geometric magnetic frustration in this system. [ABSTRACT FROM AUTHOR]

The first cooperative study of the Asian Pacific bone marrow transplantation group included 75 patients with early leukemia who received human leukocyte antigen-matched sibling bone marrow transplants and were randomized into granulocyte colony-stimulating factor and control groups. The selected patients were registered from 10 centers in six countries and areas within Asia (Beijing, Taipei, Hong Kong, Japan, Korea, and Malaysia). The incidence of grades II-IV acute graft-vs.-host disease was 22.2%, and the 2-year survival rate was 62.7%. The period of protective isolation (27.1-66.7 days), period of hospitalization (38.6-130.5 days), and medical costs for 4 months (US $10,300-US $80,803) varied considerably. Good cooperation, i.e., low rate of protocol violation or rapid and precise presentation of case reports, was obtained.

Adeno-associated virus (AAV) is a single-stranded DNA parvovirus displaying several attractive features applicable to haemophilia A gene therapy, including nonpathogenicity and potential for long-term transgene expression from either integrated or episomal forms. We have generated and characterized two B-domain-deleted (BDD) fVIII mutants, deleted in residues Phe756 to Ile1679 (fVIIIdelta756-1679) or Thr761 to Asn1639 (fVIIIdelta761-1639). [35S]metabolic labelling experiments and immunoprecipitation demonstrated intact BDD-fVIII of the predicted size in both lysates and supernatants (Mr approximately 155 kD for fVIIIdelta756-1679 and Mr approximately 160 kD for fVIIIdelta761-1639) after transient transfection into COS-1 cells. Functional fVIII quantification appeared maximal using fVIIIdelta761-1639, as evaluated by Coatest and clotting assay (98+/-20mU/ml/1x10(6) cells and 118+/-29 mU/ml/1x10(6) respectively, collection period 48 h). To bypass potential size limitations of rAAV/fVIII vectors, we expressed fVIIIdelta761-1639 using a minimal human 243 bp cellular small nuclear RNA (pHU1-1) promoter, and demonstrated VIII activity approximately 30% of that seen using CMV promoter. This BDD-fVIII (rAAV(pHU1-1) fVIIIdelta761-1639) can be efficiently encapsidated into rAAV (107% of wild type), as demonstrated by replication centre and DNAase sensitivity assays. A concentrated recombinant viral stock resulted in readily detectable factor VIII expression in COS-1 cells using a maximally-achievable MOI approximately 35 (Coatest 15 mU/ml; clotting assay 25+/-20 mU/ml/1x10(6) cells). These data provide the first evidence that rAAV is an adaptable virus for fVIII delivery, and given the recent progress using this virus for factor IX delivery in vivo, provide a new approach towards definitive treatment of haemophilia A.

Aim: To study the possible role of cGMP in the effect of L-arginine-induced arginine-vasopressin (AVP) release., Methods: In anesthetized rats, saline, L-arginine, 8-Br-cGMP, L-arginine + methylene blue (an inhibitor of guanylyl cyclase) were injected intracerebroventricularly (icv) and the plasma vasopressin level was detected with radioimmunoassay., Results: Both 8-Br-cGMP 2.53 g.L-1 and L-arginine 100 g.L-1 increased plasma AVP level [from (2.6 +/- 0.3) to (6.6 +/- 0.4) ng.L-1, and from (3.2 +/- 0.5) to (5.8 +/- 1.4) ng.L-1, respectively; P < 0.01] 5 min after the icv injection; methylene blue (3.74 g.L-1) + L-arginine (100 g.L-1) did not change plasma AVP level., Conclusion: cGMP was a mediator of the effect of L-arginine-induced AVP release.

HLA-DR is one of the markers associated with hematopoietic cell differentiation, since expression of this molecule is modulated throughout hematopoiesis. We have previously described and cloned the gene encoding factor IK, which inhibits both interferon gamma (IFN-gamma)-induced and constitutive HLA-DR expression. The current study demonstrates that IK gene transcripts are present in CD34+ cells purified from human umbilical cord blood. IK expression increased and was therefore inversely correlated with the gradual loss of HLA-DR during growth factor-induced CD34+ cell proliferation and differentiation. To study the possible role of IK in hematopoiesis, antisense probes were used. IK expression was specifically inhibited by an antisense oligodeoxynucleotide containing two phosphorothioate internucleotide linkages at each of the 3' and 5' ends and corresponding to the initiation site of IK mRNA. A control oligonucleotide was also tested in parallel. A specific decrease of IK transcripts was correlated with an increase of HLA-DR antigen expression level. In colony-forming assays, IK antisense oligonucleotide inhibited colony formation by multilineage early erythroid and granulomonocytic CD34+ progenitors. The mean colony size was decreased 70% by IK antisense oligonucleotide in comparison to controls. These results provide evidence that the IK molecule participates in the regulation of HLA-DR expression on hematopoietic cells and plays a role in growth factor-dependent CD34+ cell proliferation and differentiation by modulating HLA-DR expression.

The cytokine production by MTSC 4 cells, a murine thymic dendritic cell line established in our laboratory, has been investigated. Without exogenous stimulation, the MTSC 4 cells constitutively produce multiple types of cytokines, including IL-1, IL-6, IL-7, CSF, IFN and Chemotactic factor (CF). Of which, IL-6 and IFN were abundant: IL-1 and Chemokine, moderate: IL-7 and CSF at low level. MTSC4 cells could not produce detectable either IL-3 of TNF alpha. The establishment of MTSC 4 may be useful in the analysis of the mechanism of thymus selection, and in the study of the network regulation of autocrined cytokines.

Ten cases of acute myeloperoxidase-negative myeloid leukaemia (AML) were reported. They had no typical mopholocid negative for lymphocic features and were negative antigens. However 5 cases were positive for NSE/NaF stain. 9 of the 10 cases expressed more than one myeloid antigens. The authors are of the opinion that it is very difficult to diagnose myeloperoxidase-negative AML and combination of cytochemical and immunological techniques is recommended in this respect.

Several putative NF-kappa B-binding sites in the ICP0 and Vmw65 herpes simplex virus type-1 (HSV-1) genes have been identified. Oligonucleotides encoding some of these sites bind specifically to purified NF-kappa B protein and an NF-kappa B-like protein in nuclear extracts of phorbol ester- or cycloheximide-induced human embryonic lung (HEL) cells. HSV-1 infection of HEL cells induced a nuclear factor that binds specifically to kappa B sites in the ICP0 and Vmw65 gene regions and comigrates with complexes formed by purified NF-kappa B. The HSV-1-inducible nuclear factor bound to the authentic immunoglobulin (Ig) kappa B site. Transient expression of chloramphenicol acetyltransferase (CAT) plasmids containing two copies of the Ig kappa B site upstream of the c-fos promoter (kappa B2-CAT) showed activity in HEL cells. HSV-1 infection of kappa B2-CAT-transfected HEL cells, however, induced a dramatic increase in CAT activity; mutation in the NF-kappa B-binding site of kappa B2-CAT abolished the inducibility of CAT gene expression. Our results demonstrate that the HSV-1 ICP0 and Vmw65 gene regions contain binding sites for NF-kappa B, and that HSV-1-inducible proteins bind to NF-kappa B-like sites in the HSV-1 genome.

An untransformed murine thymic epithelial cell line (MTEC1) has been established. Without exogenous stimulation, the MTEC1 cells constitutively produced multiple types of cytokines, including IL-1, IL-6, IL-7, GM-CSF and chemotactic factor(s). Of which, IL-6, GM-CSF and chemotactic factor(s) were abundant; IL-1, moderate; and IL-7 at low level. MTEC1 cells neither produced detectable IL-3 nor TNF alpha. Thus, the MTEC1 cells may be useful not only in the evaluation of the signals required for thymic selection in vitro, but also useful in the analysis of the endogenous regulation of the autocrine cytokine production cascade.

Angle-resolved light scattering (ARLS) is used to estimate the root-mean-square (rms) slopes of rough surfaces having a well-defined lay, and the effect on slope measurements caused by changing the angles of incidence and scattering is investigated. The ARLS patterns are taken with the Detector Array for Laser Light Angular Scattering (Dallas) research instrument, and the rms slopes are obtained from the angular widths of these patterns. In general, it was found that the angular width, and thus the estimated rms slope, is surprisingly insensitive to relatively large changes in both the incident and scattering angles of light. These results are independent of surface material and are valid for both sinusoidal and random rough surfaces with lay. The principles, experiments, analyses, and conclusions involved in using ARLS to estimate rms surface slopes are described.

Ten leukemic patients were treated with allogeneic bone marrow transplantation (BMT). The diagnosis were ANLL in 6 cases, CML in 3 and ALL in one. Pretransplant immuno suppressive measures including total body irradiation cyclophosphamide and daunorubicin were given. All the patients were infused with health stem cell preparation, so that the hemopoietic function was restored. Graft versus-host disease of grade I to II was present in 5 of the patients. Leukemia recurred 76 days after BMT in one patient who received the procedure during a relapse of the disease, while in the remaining 9 patients disease-free survival from 1 to 23 months has been observed.

Shen-Qian Gu-Jing granule was used in the treatment of the menorrhagia in 72 cases including idiopathic menorrhagia 28, uterine myoma 29, endometriosis 7, intrauterine device 5, postpartum and post induced abortion 3 cases. The amount of menstrual blood loss (MBL) and the fibrin degradation products (FDP) level in menstrual fluid and peripheral blood were measured before and after treatment. 87.5% of all cases showed a significant decrease in MBL (P less than 0.05). The local FDP level significantly decreased parallel to effectiveness of MBL. The results suggested that the function of this Chinese herbs complex in menorrhagia was related to the regulation of FDP level.

The effects of two varieties of semisynthetic deoxyharringtonine on the tumor mass and survival time of mice with murine leukemia were evaluated. Compared to untreated control mice, the survival time of those with murine leukemia increased by 146% (L7212) and 68% (L615) after treatment. The LD50 for deoxyharringtonine variants DH4.8 and DH was determined to be 322 +/- 9 mg/kg and 71 +/- 1 mg/kg, respectively. Seventeen patients were then treated with either DH or DH4.8; 11% achieved complete remission, 23% achieved partial remission, and an additional 35% had markedly lower leukocyte levels after treatment. Side effects were minimal. It was concluded that deoxyharringtonine is an effective anti-leukemic agent.

The authors presented 5 cases of ANLL and 6 cases of ALL according to FAB classification and further classified them with leukemic cell morphology, cytochemistry and immunophenotyping. Five cases of them belonged to low grade peroxidase ANLL (LP-ANLL), 4 to hybrid acute leukemia (HAL) and 2 to acute undifferentiated leukemia (AUL). The importance of immunophenotyping of leukemic cells in classification of acute leukemia was emphasized and the criteria for diagnosis of LP-ANLL, HAL and AUL discussed. The authors are of the opinion that the diagnosis of these three kinds of acute leukemia is difficult and the prognosis is serious.