Circadian secretion patterns of melatonin after major surgery

Despite our advances in the diagnosis and treatment of asthma, the incidence of mortality is increasing in developed countries. As patients and health care providers seek new options for the treatment and prevention of asthma, various complementary and alternative medical therapies are being used. With funding from the Office of Alternative Medicine, National Institutes of Health, our goal was to identify the type and prevalence of complementary and alternative treatments for asthma in use in the United States in order to establish a research agenda for the study of the most promising therapies. A survey was developed by an expert panel. After undergoing a preliminary round of testing and improvement, the survey was then sent along with a postage-paid return envelope as inserts in the May 1996 issue of Alternative Therapies in Health and Medicine, a peer-reviewed periodical of complementary and alternative medical research and scholarly activity; 10,000 surveys were distributed. We asked that only those who treated asthma respond. The surveys were designed to identify characteristics of the respondent, their particular practice type, use of complementary and alternative medicine, or conventional medicine in general, patient characteristics and numbers, and their use of 20 specific potential therapies to treat asthma. A total of 564 surveys were returned. The 5.64% response rate was low but was reflective of the demographics of the readership of this journal of complementary and alternative medicine. The survey population was 46% male and 43% female; 11% did not specify gender. They ranged in age from under 31 years old to over 70. The largest group (37%) of respondents held degrees as medical doctors, 27% held doctorates in complementary and alternative medicine related disciplines, 11% had registered nursing degrees, 4% were acupuncturists and 18% did not specify their training. Practice characteristics between MD and non-MD asthma care providers did not differ. The majority had general practices (75%) seeing all ages of patients. MDs were less likely to employ complementary and alternative medicine techniques for asthma compared to non-MDs. Both groups identified dietary and nutritional approaches as their most prevalent and useful asthma treatment option. Use of botanicals, meditation and homeopathy were frequently cited; statistically significant differences appeared in the rankings of treatment usefulness and prevalence between MD and non-MDs. Non-MD asthma care providers were more likely to ask patients about their use of complementary and alternative treatments for asthma than MDs (92% vs. 70%), while both groups showed statistically significant increases in their levels of patient inquiries compared to 2 years previously (up 9% and 8% for MDs and non-MDs respectively). The predominance of diet and nutrition supplementation used by MDs and non-MDs suggests that further attention and research efforts should be directed toward this area of complementary and alternative practice. Other complementary and alternative medicine practices such as botanicals, meditation and homeopathy appear to warrant research efforts. Differences between MDs and non-MDs in their use of such therapies may reflect different philosophies as well as training.     

Effect of Ba Substitution for Sr in the Pb-based 1212 Cuprate Containing Sulfur of (Pb<Subscript>0.75</Subscript>S<Subscript>0.25</Subscript>)Sr<Subscript>2</Subscript>(Y,Ca)Cu<Subscript>2</Subscript>O<Subscript><Emphasis Type="Italic">z</Emphasis></Subscript>

We already reported on the synthesis of new Pb-based 1212 layered cuprates containing sulfur in the (Pb_0.75S_0.25)Sr₂(Y,Ca)Cu₂O _z system. There none of the samples showed superconductivity until after annealing under high O₂ pressure. More recently, we have discovered that the samples could be substituted by Ba for Sr up to x=0.6 in the composition of (Pb_0.75S_0.25)(Sr_2−x Ba _x )(Y_0.4Ca_0.6) Cu₂O _z . Then if the Ba-substitution is performed for Sr, some of the almost-single phase samples are found to show resistivity drops and magnetic anomalies without annealing under high O₂ pressure. Among the samples, a sample with the nominal composition of (Pb_0.75S_0.25)(Sr_1.5Ba_0.5)(Y_0.4Ca_0.6) Cu₂O _z is found to show the highest onset temperatures of a resistivity drop at about 35 K and a magnetic anomaly at about 31.5 K. These are higher than the highest values for the superconducting Ba-free sample of (Pb_0.75S_0.25)Sr₂ (Y_0.4Ca_0.6)Cu₂O _z which was annealed under high O₂ pressure.     

Trans-acting RNAs as molecular probes for monitoring time-dependent structural change of an RNA complex adapting two structures

As dynamic structural changes are pivotal for the functions of some classes of RNA molecule, it is important to develop methods to monitor structural changes in RNA in a time-dependent manner without chemical modification. Based on previous reports that trans-acting RNAs can be used as probes for analysis and control of 3D structures of target RNAs, we applied this method to monitor time-dependent structural changes in RNA. We designed and performed a proof-of-principle study using a simple model RNA complex that adopts two different structures as a target. The time-dependent structural changes in the target RNA were successfully monitored using two trans-acting RNAs, which stably form a ternary complex with the bimolecular target RNA and act as a catalyst to join two RNA fragments of the target complex, respectively.     

Substitution Effect of Ba for Sr on Superconductivity in?the?(Pb0.75P0.25)(Sr2?xBax)(Y0.4Ca0.6)Cu2Oz System

The Pb-based 1212 compounds containing phosphorus were already discovered by us in the (Pb,P)Sr₂(Y,Ca)Cu₂O _z system. Among the almost-single phase samples, a sample with the nominal composition of (Pb_0.75P_0.25)Sr₂(Y_0.4Ca_0.6)Cu₂O _z was a superconductor with the highest T _c of 38 K in the system. Recently, we have been investigating on substitution effect of Ba for Sr on superconductivity in the (Pb_0.75P_0.25)(Sr_2−x Ba _x )(Y_0.4Ca_0.6)Cu₂O _z system. As a result, it is found that the almost–single 1212 phase samples are obtained in the composition area of 0.0≤x≤0.4. In this area, with increase of x, the lattice parameters a,c and the cell volume V are found to be gradually increasing. This finding can be considered to show that larger Ba²⁺ ions certainly occupied the Sr-sites in the sample. However, we obtain such interesting results as that the T _c value is not so enhanced by the substitution in comparison with that of the sample of x=0.0, and that the maximum value of T _c was 40 K for x=0.2 and 0.3 at the best.     

High Field and Low Temperature Magnetization of ErCu2Si2 Single Crystal

The magnetic measurements have been performed for high fields up to 18 T and low temperatures down to 0.5 K on the single crystal compound ErCu₂Si₂. In the temperature dependence of magnetic susceptibility, two anomalies are seen at T _N =1.51 K and T _t =0.97 K which is corresponding to an antiferromagnetic ordering temperature and may come from a change of magnetic structure. Low temperature magnetization shows a metamagnetic transition around 0.4 T along the easy magnetization direction of [001]. The magnetization is almost saturated above 3 T and reaches 8.8μ _B /f.u. at 18 T. A metamagnetic transition appears around 0.5 T in the basal plane magnetization processes as well. The anisotropy within the basal plane is fairly large for high fields. These behaviors have been explained from crystalline electric field effects and magnetic interaction in terms of molecular field.     

High Field Metamagnetism of PrRh2Si2 Single Crystal Compound Having Anomalously High Nèel Temperature

High field magnetization up to 18 T and magnetic susceptibility measurements have been carried out on a PrRh₂Si₂ single crystal. The anomalously high Nèel temperature of 70 K is confirmed. A strong uniaxial magnetic anisotropy with the easy c-axis is evidenced. A sharp metamagnetic transition appears at 16 T in the easy c-axis magnetization process while magnetization in the basal plane is very small and the curve is linear. The saturation moment obtained is 3.1μ _B . Crystalline electric field (CEF) effects have been analyzed to discuss the magnetic behaviors.     

Effect of Boron Substitution for Bi on Superconductivity of the Bi-2212 Phase in the Bi-Sr-Ca-Cu-O System

Possibility of boron substitution for Bi and the substitution effect on superconductivity is investigated for the Bi-2212 phase of Bi-Sr-Ca-Cu-O. From X-ray diffraction study, it is found that samples in the (Bi_2?x B _x )Sr₂CaCu₂O _z system are mainly of the single 2212 phase in a composition range of 0.0≤x≤0.6, and both of the lattice parameters a and c change with increasing x up to 0.6. From measurements of the magnetic susceptibility and the electrical resistivity, the superconducting transition temperature is found to increase up to 0.6 with increasing x. These results are considered to show that boron is substitutable for Bi up to x=0.6 in the (Bi_2?x B _x )Sr₂CaCu₂O _z system and that the boron substitution causes the number of hole-carriers to decrease in this system.     

Boron Substitution for Bi in Sr-Free Bi-2212 Superconductor of Bi<Subscript>2</Subscript>Pr<Subscript>0.5</Subscript>Ca<Subscript>2.5</Subscript>Cu<Subscript>2</Subscript>O<Subscript><Emphasis Type="Italic">z</Emphasis></Subscript>

Possibility of boron substitution for Bi and the substitution effect on superconductivity is investigated for the Bi-2212 phase of Bi-Sr-Ca-Cu-O. From X-ray diffraction study, it is found that samples in the (Bi_2−x B _x )Sr₂CaCu₂O _z system are mainly of the single 2212 phase in a composition range of 0.0≤x≤0.6, and both of the lattice parameters a and c change with increasing x up to 0.6. From measurements of the magnetic susceptibility and the electrical resistivity, the superconducting transition temperature is found to increase up to 0.6 with increasing x. These results are considered to show that boron is substitutable for Bi up to x=0.6 in the (Bi_2−x B _x )Sr₂CaCu₂O _z system and that the boron substitution causes the number of hole-carriers to decrease in this system.     

Synthesis of New Pb-Based 1232 Cuprate Containing Boron in?the?(Pb0.5B0.5) Sr2(Er3?x?yCexSry)Cu2Oz System

New Pb-based layered cuprates containing boron with the 1232 structure have been synthesized in the (Pb_0.5B_0.5)Sr₂(Er_3−x−y Ce _x Sr _y )Cu₂O _z system. Nearly the single 1232 phase samples are obtained for the nominal composition of 1.6≤x≤1.9 and y=0.2. A sample with the composition of (Pb_0.5B_0.5)Sr₂(Er_1.2Ce_1.6Sr_0.2)Cu₂O _z shows resistivity-dropping phenomenon below 10 K and it shows a diamagnetic signal at about 9.0 K, though the superconducting volume fraction is very small. From these results, the sample may well be a new Pb-based superconductor with the 1232 structure.     

Effect of Cd Substitution for Bi on Superconductivity of the Bi-2201 Phase in the Bi—La—Ca—Cu—O System

A series of the Bi-2201 samples with the nominal composition of (Bi_2–x Cd _x )La_0.7Ca_1.3CuO _z has been synthesized and effect of Cd substitution for Bi on the superconductivity has been investigated. As a result, it is found that almost single phase samples are obtained for a considerable wide composition of 0.0 x 0.8, their crystal structures have a tetragonal or a pseudotetragonal symmetry in the whole composition range, and the sample unexpectedly changes from superconductor to semiconductor by little Cd-substitution of about 0.1. The semiconducting samples show a temperature dependence of the resistivity suggesting that the transport process is followed by a three-dimensional variable range hopping conduction.