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To help realize stable droplet manipulation, we present a study on the physical mechanism of interfacial instability and droplet atomization dynamics in acoustic levitation with ultrasonic phased arrays. Acoustic levitation is highly applicable in the fields of analytical chemistry and biology because container-less processing can prevent undesirable wall effects, such as nucleation and contamination resulting from the container walls. Although many studies demonstrated the atomization behavior in single-axis acoustic levitation, the breakup characteristics of levitated droplets in ultrasonic phased array levitation have been less studied. Here, we visualized the atomization behavior of ethanol, ethanol solution, and silicone oil droplets using a high-speed camera. The time evolution of the interfacial velocity of the droplets indicates a threshold for the droplet atomization. To elucidate atomization dynamics, the critical interfacial velocities of the levitated droplet immediately before its atomization are discussed and compared to the theoretical prediction based on the Kelvin–Helmholtz instability. Our experimental findings provide deeper physical insights into the levitation stability of droplets in ultrasonic phased array levitation for futuristic lab-in-a-drop applications. [ABSTRACT FROM AUTHOR]

Strongly enhanced quantum fluctuations often lead to a rich variety of quantum-disordered states. Developing approaches to enhance quantum fluctuations may open paths to realize even more fascinating quantum states. Here, we demonstrate that a coupling of localized spins with the zero-point motion of hydrogen atoms, that is, proton fluctuations in a hydrogen-bonded organic Mott insulator provides a different class of quantum spin liquids (QSLs). We find that divergent dielectric behavior associated with the approach to hydrogen-bond order is suppressed by the quantum proton fluctuations, resulting in a quantum paraelectric (QPE) state. Furthermore, our thermal-transport measurements reveal that a QSL state with gapless spin excitations rapidly emerges upon entering the QPE state. These findings indicate that the quantum proton fluctuations give rise to a QSL—a quantum-disordered state of magnetic and electric dipoles—through the coupling between the electron and proton degrees of freedom. [ABSTRACT FROM AUTHOR]

Cytological diagnosis after trachelectomy is challenging. Sharing information can help cytopathologists and gynecologic oncologists to acquire sufficient information and to provide patients with appropriate care. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate the effects of long-term treatment with sulindac on the progression of diabetic retinopathy (DR). RESEARCH DESIGN AND METHODS: 40 Japanese patients with type 2 diabetes were enrolled in a randomized, single-blind controlled trial in which the effects of sulindac (200 mg/day, 100 mg twice a day; n = 16 patients) on the progression of DR were compared to controls (24 patients) for 3 years. All patients were comparable in their age, gender, duration of disease, body mass index, dipstick proteinuria, insulin therapy, glycemic control, and clinical stages of DR. Outcome was determined by comparing parameters of retinopathy in fundus photographs that were taken at time 0 to those taken 1, 2, and 3 years after the initiation of treatment. RESULTS: Patients in the sulindac group did not develop DR during the course of treatment nor was there progression of pathology in those who began the study with mild non-proliferative DR (NPDR). On the other hand, six patients progressed to mild NPDR in the control group--three at year 1 and three at year 3--and an additional patient progressed to severe NPDR from mild NPDR by year 1 and to proliferative DR by year 2. The findings at year 3 in the sulindac group were significantly (p < 0.05) different from the control group. None of the patients experienced any adverse effects of treatment. CONCLUSIONS: Long-term treatment with sulindac was clinically effective in decreasing the progression of mild DR in type 2 diabetic patients in this pilot study. [ABSTRACT FROM AUTHOR]

Syngeneic inoculated metastatic mammary cancers received direct intratumoral injection of a plasmid vector containing either endostatin (pEndo) with or without a suicide gene (pHSVtk), pHSVtk alone or control vector once a week for 8 weeks. We applied electrogene transfer to the tumors after each injection and administered ganciclovir (GCV) to pHSVtk-transfected mice using an osmotic minipump. Anticancer efficacy was monitored using a variety of parameters, namely tumor volume, intratumoral microvessel density and DNA synthesis, number of mice with metastasis, and number of sites of metastasis per mouse. Tumor volume was significantly lower in all therapeutic groups, with the most effective growth suppression in the pEndo+pHSVtk/GCV group. Lymph node metastasis was significantly less frequent in all therapeutic groups, whereas the multiplicity of lung metastases was significantly lower only in the pEndo and pEndo+pHSVtk/GCV groups. All therapeutic groups showed significantly lower intratumor microvessel density and DNA synthesis. The pEndo and pEndo+pHSVtk/GCV groups also showed a significant reduction in the numbers of dilated lymphatic vessels containing intralumenal tumor cells. Our data suggest that endostatin electrogene therapy alone or in combination with pHSVtk/GCV suicide gene therapy is more beneficial than suicide gene therapy alone. The observed antimetastatic activity of endostatin may be of high clinical significance in the treatment of metastatic breast cancer.Cancer Gene Therapy (2007) 14, 268–278. doi:10.1038/sj.cgt.7701009; published online 10 November 2006 [ABSTRACT FROM AUTHOR]

The application of ultrasonic waves enhanced the wetting of alumina by Zn–Al filler alloy. Alumina ceramic was brazed to different metals such as Ti, Ni, Nb, Fe, and AISI 304 stainless steel using the Zn–5 mass-%Al brazing filler alloy. Different reaction products were formed at the alumina–metal interfaces, including solid solutions and intermetallic compounds. The alumina–Nb joint exhibited the highest bond strength value among the different couples, because Nb produces the lowest residual stress among the alumina–metal joints. The high mismatch in thermal expansion coefficient between the brazing filler and the AISI 304 stainless steel yielded the lowest bond strength among the joints. [ABSTRACT FROM AUTHOR]

Carbon steel is joined to aluminium using the ultrasonic brazing method with Zn–Al filler at 663 K, employing different ultrasound application times. Different reaction layers could be observed at the interface, containing compounds such as FeAl3, Fe2Al5, Fe3Al, and FeAl, and solid solutions such as Fe–Zn and Zn–Al. For shorter ultrasound application times, formation of the aluminium rich Fe–Al compounds occurred; conversely, after longer ultrasound times formation of the iron rich Al–Fe compounds occurred, which improves the joint bond strength. The maximum bond shear strength of 127 MPa was obtained for an Al–steel joint brazed at 663 K with 3 s ultrasound application time. Extending the ultrasound time beyond 3 s caused the formation of FeAl compound, which decreased the joint bond strength; however, the strength of the joints remained at a higher level than that obtained with FeAl3 and Fe2Al5. [ABSTRACT FROM AUTHOR]

A filler alloy (Zn–14 at.-%Al) was used to join aluminium to 304 type stainless steel by ultrasonic brazing at 673 K for different ultrasound application times. Different reaction layers could be observed at the interface, containing Fe–Al, Fe–Zn, and Al–Zn solid solutions. As the amount of these solid solutions increased at the interface, there was a gradual improvement in the joint bond strength. The maximum bond strength of 146 MPa was obtained for the Al–304 joint brazed at 673 K for 3 s ultrasound application time. A critical remaining thickness of the filler alloy after ultrasonic application improves the interfacial joining. Extending the ultrasound application time beyond 3 s causes a bulk escape of the brazing alloy from the interface and leads to a direct interaction between aluminium and 304, which increases the possibility of forming intermetallics, and consequently decreases the joint bond strength. [ABSTRACT FROM AUTHOR]

Si3N4 ceramic was joined to itself using a filler alloy of (CuZn)85Ti15 at 1123-1323 K for 15 mi TEM observation showed that a reaction zone of TiN and/or Ti2N exists at the interface between the ceramic and filler alloy, and the center of the joint is composed of Cu-Zn solid solution in which there are Cu2TiZn and Ti5Si3 reaction phases. With increasing brazing temperature, both the thickness of the reaction zone and the amount and size of the Ti5Si3 phase increase, while the amount and size of the Cu2TiZn phase decrease. When the brazing temperature reached 1323 K, the Cu2TiZn phase disappeared. When the brazing temperature is lower than 1223 K, the interfacial reaction zone is mainly composed of Ti2, which has a cylindrical shape and orientates randomly in the zone. There is a crystal orientation relationship between the Ti2N in the reaction zone and the Cu in the Cu-Zn solid solution, which is: {110}Ti2N//{420}Cu, (001Ti2N//(001)Cu. When the brazing temperature is higher than 1223 K, the interfacial zone is composed of TiN, which has a plate shape crossing each other. [ABSTRACT FROM AUTHOR]

Si3N4 ceramic was jointed to itself using a filler alloy of Cu-Zn-Ti at 1123-1323 K for 0.3-2.7 ks. Ti content in the Cu-Zn-Ti filler alloy was varied from 5 to 20 at.-%. The effect of brazing parameters, such as brazing temperature, holding time and Ti content, on the mechanical properties and facture processes of the Si3N4/Si3N4 joint were investigated. The results indicated that the increased brazing temperature, holding time and Ti content increase the thickness of the interfacial reaction zone in the Si3N4/filler alloy, and the size and amount of the reaction phases in the filler alloy. Their increases lead to increasing shear strength of the joint. The fracture behaviour of the Si3N4/Si3N4 joint greatly depends on the microstructure of the joint. A suitable thick reaction zone with reaction phases yields the high strength of the Si3N4/ Si3N4 joint. [ABSTRACT FROM AUTHOR]

Ultrasonic waves were applied during brazing of alumina to copper, The intensity of ultrasonic wave was 1 kW and 18 kHz and the aim of this work was to study the effect of the ultrasonic wave and brazing temperature on the properties of the braze joint between alumina and copper using Zn-Al alloys as filler metal. First the alumina was metallized by applying on ultrasonic wave in a Zn-Al braze bath. Then the metallized alumina was brazed with copper using the same filler alloy. The joining mechanism was investigated by measuring the joining strength and analyzing the microstructure at the interface of the joint. The ultrasonic waves improved the wetting in the molten Zn-Al bath by accelerating the removal of bubbles from the interface between alumina and the filler, and this was reflect in improved joint strength. [ABSTRACT FROM AUTHOR]

The present study describes combined transcriptome and metabolome analysis for therapeutic target validation in hypoxia-induced vascular remodeling. Exposure to hypoxic conditions resulted in the upregulation of S100C mRNA and increased taurine (2-aminoethanesulfonic acid) content in the rat lung, as demonstrated by differential display and amino-acid content analysis. Hypoxia resulted in transcriptional activation of the S100C promoter through hypoxia-inducible factor-1 (HIF-1). Taurine suppressed HIF-1-mediated increases in S100C transcription. Moreover, oral taurine administration attenuated vascular remodeling in hypoxic rat lung, whereas depletion of endogenous taurine by administration of beta-alanine resulted in increased vascular remodeling. Inhibition of HIF transcription by taurine may be of therapeutic benefit in preventing hypoxia-induced vascular remodeling. In conclusion, we used transcriptome and metabolome analysis to identify a therapeutic low-molecular-weight ligand that plays a critical role in hypoxia-induced vascular remodeling. These techniques provided an excellent strategy for screening and validation of targets.The Pharmacogenomics Journal (2003) 3, 183-188. doi:10.1038/sj.tpj.6500177 [ABSTRACT FROM AUTHOR]

Objective: To clarify mortality and morbidity of intensively managed elderly diabetic individuals and to explore factors predicting mortality and diabetes-related end points.Research Design and Methods: A total of 390 elderly (>or=65 years of age) outpatients with type 2 diabetes ( 173 men and 217 women, mean age 73.0 years) were analyzed. The mean HbA(1c) upon entry was 6.8% (332 receiving oral hypoglycemics and/or insulin) and blood pressure upon entry was 136/74 mmHg (219 receiving antihypertensive drugs). The patients have been followed-up for 3 years with HbA(1c) <7.0% and blood pressure <145/80 mmHg as targets, with mortality and an aggregate of fatal and nonfatal diabetes-related events as end points. Mortality rate and causes of mortality, as well as risk factors for mortality and morbidity, were determined.Results: The mortality rate, 2.9% per year, was comparable to that of the age- and sex-matched general population. Stroke was a leading cause of mortality after malignancy. By the univariate Cox proportional hazards model, only high serum creatinine and prior stroke were highly significant and strong risks for both end points. In those without prior stroke and receiving antihypertensive agents, the incidence of the diabetes-related end point based on their systolic blood pressure (SBP) quartile was U-shaped, with the nadir at the 3rd (SBP, 137-147 mmHg) and the peak at the 1st (SBP Conclusions: In well-controlled elderly diabetic subjects, there was no excessive mortality compared to the age- and sex-matched general population. Renal dysfunction and prior stroke were independent risks for mortality and morbidity. In those without prior stroke, a risk of too much lowering of blood pressure was suggested. [ABSTRACT FROM AUTHOR]

Vacuum diffusion bonding of SiC ceramic to Ni–25 at.-%Cr alloy was carried out at 1223–1323 K for 0.9–3.6 ks under a pressure of 7.2 MPa. The kinds of the reaction products and the interface structures of the joints were investigated by scanning electron microscopy (SEM), electron probe microanalysis (EPMA), and X-ray diffraction (XRD), and the kinetic parameters describing the growth of reaction layers were calculated. The experiment and analysis identify that four kinds of reaction products, namely Ni[sub 2]Si, graphite (G), Ni[sub 5]Cr[sub 3]Si[sub 2] and Cr[sub 3]Ni[sub 2]SiC, have formed during the diffusion bonding of SiC ceramic to Ni–25 at.-%Cr alloy. The interface structure of the SiC/Ni–Cr joints is SiC/(Ni[sub 2]Si+G)/(Cr[sub 3]Ni[sub 2]SiC + Ni[sub 5]Cr[sub 3]Si[sub 2])/Ni[sub 5]Cr[sub 3]Si[sub 2]/Ni- Cr, and each reaction layer in this structure grows according to a parabolic law. The activation energies for growth of (Ni[sub 2]Si+G), (Cr[sub 3]Ni[sub 2]SiC+Ni[sub 5]Cr[sub 3]Si[sub 2]), and Ni[sub 5]Cr[sub 3]Si[sub 2] are 217, 248, and 233 kJ mol ­ 1, respectively. [ABSTRACT FROM AUTHOR]

In the present work, the polytypism of SiC and the interfacial structure between SiC and Al were investigated using X-ray diffraction (XRD) and high resolution transmission electron microscopy (HREM). It was approved that 15R could be juxtaposed with 6H stacking sequences in the same SiC reinforcement and a structural transformation zone was also observed. The Al4C3 compound can nucleate on SiC at the SiC/Al interface with the growth orientation parallel to the C axis of SiC. Mechanisms for the observed phenomena were also discussed in detail. [ABSTRACT FROM AUTHOR]

In this paper the results are presented of work dealing with the microstructure of ZrO2-Ni-Si3N4 diffusion bonds. Joints were made at 1050°C with bonding times between 22.5 and 360 minutes. The interfacial structure was studied using optical microscopy, scanning electron microscopy and transmission electron microscopy. The element concentrations in the joint were determined by electron probe microanalysis. It was found that at the ZrO2-Ni interface no reactions take place, whereas at the Si3N4-Ni interface decomposition of Si3N4 occurs, resulting in a solid solution of Si in Ni and porosity due to the recombination of N to N2. [ABSTRACT FROM AUTHOR]

The composite interfaces play an important role in determining the resultant composite properties, especially the development of interfacial reaction during remelting is critical to the commercialization and sustainable-development of metal matrix composites. In this paper, the interfacial reaction characteristics of SiCp/Al-Si system composites during multiple-remelting were investigated by Differential Scanning Calorimeter (DSC). It was found that the interfacial reactions were not sensitive to remelting number, remelting temperature and reinforcement volume fraction after a degree of reaction, and the results also suggested that the preventation effects of Si upon the interfacial reaction SiCp/Al were mainly attributed to the Si released from the interfacial reaction, while the original Si content in the master alloy also has the same effect only after a given Si content. [ABSTRACT FROM AUTHOR]

SiC was bonded to SiC using V foil at temperatures ranging from 1473 K to 1673 K for 1.8 to 64.8 × 10 s and 30 MPa in vacuum. Interfacial reactions and microstructures were investigated using electron probe microanalyser and X-ray diffractometer. SiC begins to react with V at temperatures above 1473 K. Granular VC phase was formed at the V side of the reaction zone, while a layer of VSi phase was formed at the interface between VC and SiC after bonding at 1573 K for 1.8 and 7.2 × 10 s. The same reaction structure can be observed at 1473 and 1673 K for 1.8 × 10 s. Hexagonal VSiCx (X < 1) phase was formed at the interface between VSi and SiC after bonding at 1573 K for 14.4 and 21.6 × 10 s, and the interface structure of the joint became SiC/VSiCx/VSi/VC + V/V. This microstructure represents a complete diffusion path which is correlated with the corresponding Si-V-C phase diagram. At the longer bonding time of 64.8 × 10 s, V was completely consumed, and the joint showed the layer structure of SiC/VSiCx/VSi/VC/VSi/VSiCx/SiC. [ABSTRACT FROM AUTHOR]

Solid-state bonding at pressureless-sintered SiC has been carried out using 25-μm Cr foil at temperatures from 1373 to 1773 K for 1.8 ks in vacuum. The formation of reaction phases and microstructures at the interface between SiC and Cr was investigated by X-ray diffraction and microprobe analysis. At the bonding temperature of 1373 K the cubic CrCphase formed next to Cr, and the hexagonal CrC phase formed next to SiC. At 1473 K the cubic phase CrSiC appeared additionally on the SiC side. At 1573 K the complete diffusion path was established. Upon increasing the joining temperature beyond 1573 K all the chromium was consumed, and CrC and CrSiC dissolved. A layered structure consisting of SiC/CrSi C/CrC/CrSi C/SiC occurred. [ABSTRACT FROM AUTHOR]

Soft x-ray magnetic circular dichroism (XMCD) and element-specific magnetic hysteresis (ESMH) measurements were performed in transmission mode on Mn73Ir27 10 nm/Co70Fe30 2 nm bilayers with different chemical orderings of the Mn–Ir layer.The unidirectional anisotropy constant was 0.55 erg/cm2 for the disordered Mn–Ir layer and 1.18 erg/cm2 for the ordered Mn–Ir layer. The XMCD signal of Mn was observed, which means the induced ferromagnetic component of Mn spins through the exchange coupling at the interface. No vertical offset of the Mn ESMH loops was observed for either the disordered or the ordered bilayers, which means that insignificant uncompensated Mn spin was pinned at the interface to induce exchange bias on the Co–Fe layer. [ABSTRACT FROM AUTHOR]

Angular dependence of Hex and Hc, and the critical angle behavior are measured in CoFe/MnIr bilayers annealed at 200°C and 340°C. The interfacial exchange coupling anisotropy and the antiferromagnet anisotropy at tAF < tAFcare estimated from the best fitting of angular dependence of Hex and Hc using Stoner-Wohlfarth (S-W) model. These results confirm existence of interfacial exchange coupling anisotropy between F and AF layers for tAF < tAFc. The measured critical angles for tAF > tAFc as well as for tAF < tAFc are well explained using S-W model. [ABSTRACT FROM AUTHOR]

Discusses the process of brazing silicon nitride ceramic using a copper palladium titanium filler alloy for high-temperature applications. Improving the thermal and oxidation resistance of ceramic joint; Pressure sintering process; Attractive material for engineering applications; Joining techniques; Morphology and elemental analysis results.

We investigated the effects of the purified catalytic subunit (C subunit) of the cAMP-dependent protein kinase (A-kinase) on the cardiac Na channel currents. Single Na channel currents in guinea-pig ventricular myocytes were recorded using the patch clamp technique of the inside-out configuration. Application of C subunit decreased the peak average current and slowed the current decay, effects which were caused by decrease in the open probability of Na channels and increase in the first latency, whereas the unitary current amplitude and mean open times were not affected. We conclude that the cardiac Na channel is directly modulated by phosphorylation process through A-kinase. [ABSTRACT FROM AUTHOR]

Abstracts are not published in this journal [ABSTRACT FROM AUTHOR]