Clarification of the ordering of intercalated Fe atoms in FexTiS2 and its effect on the magnetic properties.

Even though there has been a lot of studies on the magnetic properties of FexTiS2 and their corresponding atomic structures at different Fe concentrations, the dependency of the properties on the Fe atomic arrangement has not been fully clarified yet. In this study, FexTiS2 structures, synthesized by chemical vapor transport technique at Fe concentrations of 0.05, 0.10, 0.15, 0.20 0.25 and 0.33, were observed three-dimensionally using a transmission electron microscope and their corresponding magnetization values were measured using a superconducting quantum interference device. The results show a switch from local in-plane two-dimensional (2D) ordering of \sqrt 3 a and 2a at concentrations below 0.15 to three-dimensional (3D) ordering of 2a × 2a × 2c at x = 0.20 and 0.25, as well as \sqrt 3 a × \sqrt 3 a × 2c superstructures at x = 0.33, although it should be noted that the x = 0.20 sample only had partial ordering of Fe atoms. The type of Fe ordering present in FexTiS2 could be explained by the balance of cohesive energy of neighboring Fe atoms and local strain energy imposed on the host structure due to the formation of Fe clusters. It is also found that the switch from 2D to 3D Fe order coincides with the magnetic measurements, which reveal spin-glass behavior below x = 0.15 and ferromagnetic behavior above x = 0.20. This suggests that the magnetic properties of the FexTiS2 structure are highly influenced by the ordering of Fe atoms between planes.

Dietary glycine improves urine storage symptoms in urology outpatients.

OBJECTIVES: Spinal glycinergic mechanisms inhibit the micturition reflex, and administration of glycine inhibits bladder activity in rats. Therefore, we examined whether dietary glycine would improve storage symptoms in urological outpatients. METHODS: We enrolled 20 participants (16 men and four women) with an overactive bladder symptom score (OABSS) ≥ 3. All participants took 3 g of glucose (placebo) twice a day for the first four weeks, then 3 g of glycine twice a day for the next four weeks. We evaluated blood pressure, international prostate symptom score (IPSS), nocturia quality of life (N-QOL) score, OABSS, frequency of urination, sleep latency, time to first nighttime void, bladder pain, global self-assessment (GSA) evaluated urinary symptom improvement, and adverse events. RESULTS: Glucose administered as a placebo improved urinary frequency, urine force on the IPSS, and five of the 13 items on the N-QOL. However, compared to the results before and after glucose administration, glycine treatment decreased the number of nocturnal voids, urgency, and total score for urine storage items on the IPSS. It also reduced blood pressure and improved IPSS-QOL. For the OABSS, improvements with glycine were noted in the number of nocturnal urinations, urinary urgency, urge incontinence, and total score. For the N-QOL, eight of 13 items, and the total score, improved. The actual number of nighttime urinations, sleep latency, latency to first nighttime urination, bladder pain, and GSA also improved. There were no adverse events. CONCLUSIONS: Glycine might improve urine storage symptoms, cardiovascular function, pain, and sleep.

Gram-Scale Synthesis of Tetrahedrite Nanoparticles and Their Thermoelectric Properties.

Here, we report a method for facile gram-scale synthesis of tetrahedrite (Cu12Sb4S13) nanoparticles (NPs) with high quality and good reproducibility. The obtained NPs had a well-defined tetrahedral shape with a mean edge length of ∼70 nm. We sintered the NPs by the hot press technique to fabricate a nanostructured pellet for thermoelectric measurements. The figure of merit (ZT) value of the pellet was 0.52 at 675 K, which was comparable with the ZT value of the non-nanostructured counterpart.

Nanobulk Thermoelectric Materials Fabricated from Chemically Synthesized Cu3Zn1-x Al x SnS5-y Nanocrystals.

Direct energy conversion of heat into electricity using thermoelectric materials is an attractive solution to help address global energy issues. Developing novel materials composed of earth-abundant and nontoxic elements will aid progress toward the goal of sustainable thermoelectric materials. In this study, we chemically synthesized Cu-Zn-Sn-S nanocrystals and fabricated a Cu3ZnSnS5-y thermoelectric material using nanocrystals as building blocks. The figure-of-merit (ZT) value of the Cu3ZnSnS5-y material was found to be 0.39 at 658 K. We substituted Zn with Al in the Cu3ZnSnS5-y system to form Cu3Zn1-x Al x SnS5-y (x = 0.25, 0.5, 0.75, and 1) to lower the lattice thermal conductivity of the resulting materials. Complete substitution of Al for Zn substantially decreased the lattice thermal conductivity and dramatically increased the electrical conductivity of the material. However, the ZT value could not be significantly enhanced, which could be primarily attributed to the high carrier thermal conductivity. These results highlight the production of Cu3Zn1-x Al x SnS5-y thermoelectric materials and unveil the scope for improvement of ZT values by altering transport properties.

Chalcopyrite Nanoparticles as a Sustainable Thermoelectric Material.

In this report, copper iron sulfide nanoparticles with various composition were synthesized by a thermolysis based wet chemical method. These inherently sustainable nanoparticles were then fully characterized in terms of composition, structure, and morphology, as well as for suitability as a thermoelectric material. The merits of the material preparation include a straightforward bulk material formation where particles do not require any specialized treatment, such as spark plasma sintering or thermal heating. The Seebeck coefficient of the materials reveals P-type conductivity with a maximum value of 203 µV/K. The results give insight into how to design and create a new class of sustainable nanoparticle material for thermoelectric applications.

[Defining the role of sevelamer chloride as a therapeutic agent for management of phosphate in patient with hemodialysis].

It has been about 18 months after the commercial release of sevelamer hydrochloride. I examined the phosphorus management in patient with hemodialysis with the use sevelamer hydrochloride. The phosphorus reduction of sevelamer hydrochloride was weaker than the precipitated calcium carbonate. Patients on artificial dialysis must undergo dietary therapy for the sevelamer hydrochloride to be effective. However, by switching from precipitated calcium carbonate to sevelamer hydrochloride, the calcium level dropped, and as a result the intact PTH rose. It was possible to subdue the rise of intact PTH with vitamin D. The usefulness of vitamin D dramatically increased with the decrease and the eventual cancellation of precipitated calcium carbonate. Furthermore, the calcium load lightened and the product of calcium and phosphorus decreased. At this point, I do not expect substantial phosphorus reduction from sevelamer hydrochloride. It must be recognized that the basis of phosphorus management is proper diet. Only with that can sevelamer hydrochloride be used to its fullest potential.

A study of micturition inducing sites in the periaqueductal gray of the mesencephalon.

PURPOSE: The mesencephalon, especially the periaqueductal gray, is believed to integrate specific movement patterns of the somatic and autonomic nervous system, including those of vocalization, defensive behaviors and others. Fiber communications exist between the periaqueductal gray and the pontine micturition center, and many nerve fibers ascending from the sacral spinal cord project to the periaqueductal gray. We examined whether the mesencephalon is involved in micturition function using microstimulation and a neurotracer. MATERIALS AND METHODS: We decerebrated 28 adult cats under general anesthesia. An electrode that can be used for microinjection was positioned in stereotaxic fashion in the mesencephalon and pons. Subsequently electrical stimulation and chemical stimulation with DL-homocysteine acid were applied to search for micturition inducing sites. Blood pressure and respiration were monitored simultaneously. We also performed electrical microstimulation of pontine micturition center. The neurotracer 5% Fluoro-Gold (Denver, Colorado) was injected into these sites to identify neural pathways between the mesencephalon and pons. The brainstem was removed after 10 hours and the mesencephalon was examined by fluorescence microscopy. RESULTS: Bladder contraction was provoked by electrical and chemical stimulation applied mainly at the ventrolateral side of the periaqueductal gray. Blood pressure increased simultaneously with bladder contraction after periaqueductal gray stimulation. Neurotracer injected into the pontine micturition center was found mainly on the ventrolateral side of the periaqueductal gray, in agreement with the sites where micturition was provoked by microstimulation. CONCLUSIONS: Nerve cells on the ventrolateral side of the periaqueductal gray have neural communications with the pontine micturition center bilaterally and they regulate micturition.