399 research outputs found
Cationic flocculants derived from native cellulose: Preparation, biodegradability, and removal of dyes in aqueous solution
Water-soluble quaternized celluloses with various substitution degrees were prepared. The polymers showed excellent flocculation ability against anionic dyes; this ability was strongly dependent on the substituent degree and not affected by the temperature and pH of the dye solution. The flocculation ability was accurately fitted by a pseudo-second order kinetic model, which enabled reliable predictions of the flocculation behavior. In addition, the flocculation behavior of the anionic dyes followed the Langmuir adsorption isotherm model, whose analysis revealed the maximum anionic dye coagulation/flocculation capacity. The quaternized celluloses could be regenerated by washing in NaOH solution and precipitation in acetone. The quaternized celluloses exhibited good biodegradability, with a maximum degradation of 48% within 48 h using cellulase. These encouraging results indicate that the cationic celluloses could be applicable for use as reusable flocculants for wastewater treatment, leading to an environmentally friendly method to the removal of dyes from aqueous solutions
A table-top, repetitive pulsed magnet for nonlinear and ultrafast spectroscopy in high magnetic fields up to 30 T
We have developed a mini-coil pulsed magnet system with direct optical
access, ideally suited for nonlinear and ultrafast spectroscopy studies of
materials in high magnetic fields up to 30 T. The apparatus consists of a small
coil in a liquid nitrogen cryostat coupled with a helium flow cryostat to
provide sample temperatures down to below 10 K. Direct optical access to the
sample is achieved with the use of easily interchangeable windows separated by
a short distance of ~135 mm on either side of the coupled cryostats with
numerical apertures of 0.20 and 0.03 for measurements employing the Faraday
geometry. As a demonstration, we performed time-resolved and time-integrated
photoluminescence measurements as well as transmission measurements on InGaAs
quantum wells.Comment: 7 pages, 6 figure
Treatment of Mesh Skin Grafted Scars Using a Plasma Skin Regeneration System
Objectives. Several modalities have been advocated to treat traumatic scars, including surgical techniques and laser resurfacing. Recently, a plasma skin regeneration (PSR) system has been investigated. There are no reports on plasma treatment of mesh skin grafted scars. The objective of our study is to evaluate the effectiveness and complications of plasma treatment of mesh skin grafted scars in Asian patients. Materials and Methods. Four Asian patients with mesh skin grafted scars were enrolled in the study. The plasma treatments were performed at monthly intervals with PSR, using energy settings of 3 to 4 J. Improvement was determined by patient questionnaires and physician evaluation of digital photographs taken prior to treatment and at 3 months post treatment. The patients were also evaluated for any side effects from the treatment. Results. All patients showed more than 50% improvement. The average pain score on a 10-point scale was 6.9 +/− 1.2 SD and all patients tolerated the treatments. Temporary, localized hypopigmentation was observed in two patients. Hyperpigmentation and worsening of scarring were not observed. Conclusions. Plasma treatment is clinically effective and is associated with minimal complications when used to treat mesh skin grafted scars in Asian patients
Reality of Gastric Cancer in Young Patients: The Importance and Difficulty of the Early Diagnosis, Prevention and Treatment
Gastric cancer usually arises in middle-aged to older patients, and is rarely found in younger patients. The clin-ical characteristics, etiology, prognosis, preventive methods and treatment of gastric cancer in young patients have not been fully investigated because of its low prevalence. In this review, we discuss the current under-standing and clinical problems associated with gastric cancer in young patients. Helicobacter pylori (H. pylori), which is a major cause of gastric cancer, especially in older populations, is closely associated with gastric cancer in young patients as well as in older patients. Gastric cancer in young patients tends to be diagnosed at an advanced stage with alarm symptoms. However, young patients with advanced gastric cancer tend to have a favorable general condition and organ function, so they can tolerate intensive systematic chemotherapy. Unfortunately, the prognosis of gastric cancer in young patients with an advanced stage is not favorable. We should not take this rare disease lightly, given its poor prognosis if patients are diagnosed at an unresectable stage. The evaluation of the H. pylori infection status and performance of H. pylori eradication therapy to prevent gastric cancer in young patients as well as the development of more intensive chemotherapy regimens for unre-sectable gastric cancer in young patients are warranted
Novel Composite Thick-Film Electrodes Consisted of Zinc Oxide and Silicon for Lithium-Ion Battery Anode
As a novel anode for Li-ion battery, ZnO/Si composite thick-film electrodes with various ratios of ZnO:Si were prepared by a gas-deposition method using a commercial Si powder and a radial-shaped ZnO powder synthesized by a precipitation method. We investigated the effect of the ZnO amount and the radial morphology on the anode performance, comparing with charge–discharge properties of a ZnO electrode without Si. The ZnO electrode showed a stable cyclability and a moderate discharge capacity of 160–220 mA h g-1 after the 20th cycle. The composite electrode of ZnO/Si with a ratio of 89/11 wt.% exhibited a good cycle stability after the 20th cycle and large discharge capacities exceeding the theoretical capacity of graphite until the 370th cycle. In contrast, a composite electrode containing of crushed ZnO showed a flat surface and poor performance. These results revealed that microstructure of the radial-shaped ZnO is very favorable for improving efficiencies of electrode reactions due to its high surface area, and is effective in accommodating the stresses induced by Li-insertion and Li-extraction in/from Si
Site-specific differences in T lymphocyte composition of the gastric mucosa after Helicobacter pylori eradication
In our earlier work, we revealed that inflammation of the lesser curvature of the gastric body and antrum could constitute independent risk factors for gastric cancer development, while inflammation of the greater curvature was not. The aims of this study were as follows: first, to reveal the differences between T lymphocyte populations of the gastric antrum and the greater and lesser curvatures of the gastric body in patients after Helicobacter pylori eradication; second, to analyze the correlation between the composition of the stomach-resident T lymphocytes and time from H. pylori eradication; and third, to evaluate the sex differences in T lymphocyte subsets after H. pylori eradication. To investigate site-specific differences in stomach-resident T lymphocytes after H. pylori eradication, we performed flow cytometry analysis on samples taken from the gastric antrum, greater curvature of the gastric body, and lesser curvature of the gastric body of 20 patients. We also analyzed the correlation between the composition of the stomach-resident T lymphocytes and the time from H. pylori eradication. The lymphocyte subsets of the antrum and lesser curvature of the body were similar. In contrast, compared to those in the greater curvature of the gastric body, CD4(+)/CD3(+) lymphocyte subsets (43.8 +/- 19.4% vs 31.7 +/- 14.6%) were elevated in the lesser curvature of the body, whereas CD8(+)/CD3(+) (67.1 +/- 21.3% vs 80.4 +/- 12.0%), CD7(+)/CD3(+) (91.2 +/- 4.6% vs 93.7 +/- 3.8%), CCR4(+)/CD3(+) (7.7 +/- 8.1% vs 10.4 +/- 7.0%), CD45RA(+)/CD3(+)CD4(+) (27.2 +/- 24.8% vs 39.5 +/- 20.8%), and CD45RA(+)/CD3(+)CD4(-) (14.2 +/- 11.1% vs 18.7 +/- 11.5) were lower. Linear regression analysis showed a negative correlation between the time after H. pylori eradication and CD4(+)/CD3(+) (P < .05, R-2 = 0.198). There were no significant differences between men and women with respect to the lymphocyte populations. These results indicate that there are site-specific differences in lymphocyte composition in the stomach after H. pylori eradication
Angle-resolved photoemission spectroscopy with an tunable magnetic field
Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool for
probing the momentum-resolved single-particle spectral function of materials.
Historically, magnetic fields have been carefully avoided as
they are detrimental to the control of photoelectron trajectory during the
photoelectron detection process. However, magnetic field is an important
experimental knob for both probing and tuning symmetry-breaking phases and
electronic topology in quantum materials. In this paper, we introduce an easily
implementable method for realizing an tunable magnetic field
at the sample position in an ARPES experiment and analyze magnetic field
induced artifacts in ARPES data. Specifically, we identified and quantified
three distinct extrinsic effects of a magnetic field: Fermi surface rotation,
momentum shrinking, and momentum broadening. We examined these effects in three
prototypical quantum materials, i.e., a topological insulator (BiSe),
an iron-based superconductor (LiFeAs), and a cuprate superconductor
(BiSrCaCuO), and demonstrate the feasibility of ARPES
measurements in the presence of a controllable magnetic field. Our studies lay
the foundation for the future development of the technique and interpretation
of ARPES measurements of field-tunable quantum phases.Comment: 23 pages, 6 figure
Scoring systems for differentiating gastrointestinal stromal tumors and schwannomas from leiomyomas in the stomach
There is no practical predictive model for the diagnosis of gastrointestinal stromal tumors (GISTs). To establish a practical predictive model for the diagnosis of subepithelial lesions in the stomach, we reviewed patients with GISTs (n = 89), schwannomas (n = 7), and leiomyomas (n = 28). The tumor was more frequently found along the gastric cardia in the leiomyoma group (57.1%) than in the GIST/schwannoma group (2.1%, P < .01). Contrast enhancement (57.3% vs 0%, P < .01) and intra-tumoral necrosis (34.4% vs 0.0%, P < .01) were more frequently observed in the GIST/schwannoma group than in the leiomyoma group. On endoscopic ultrasonography, 58.3% of GISTs/schwannomas showed uneven echogenicity, whereas the echogenicity was uneven in 21.4% of leiomyomas (P < .01). There were no differences between the tumor color and the presence or absence of ulcer formation, tumor bleeding, irregularity of the tumor margin, cystic spaces, and hyperechoic spots between the 2 groups. Based on these results, we developed a 2-step diagnostic algorithm for GISTs/schwannomas. The first step comprises 1 endoscopic feature: a cardiac or non-cardiac location. Tumors with a cardiac location were judged as leiomyomas and those with a non-cardiac location were judged as GISTs/schwannomas, with 96.9% sensitivity and 57.1% specificity for GIST/schwannoma diagnosis. The second step comprises a combination of endoscopic (non-cardiac location), radiologic (positive contrast enhancement and intra-tumoral necrosis), and endosonographic (uneven echogenicity) features for a total of 4 points. We assigned 1 point to each feature. Tumors with scores of 2 to 4 were judged as GISTs/schwannomas, with 81.3% sensitivity and 92.9% specificity for GIST/schwannoma diagnosis. Our predictive model will be a practical guide for the management of gastric subepithelial lesions
Locomotive syndrome is associated with body composition and cardiometabolic disorders in elderly Japanese women
The 25-question Geriatric Locomotive Function Scale [7]. (DOCX 154 kb
Terahertz cavity magnon polaritons
Hybrid light-matter coupled states, or polaritons, in magnetic materials have
attracted significant attention due to their potential for enabling novel
applications in spintronics and quantum information processing. However, most
studies to date have been carried out for ferromagnetic materials with magnon
excitations at gigahertz frequencies. Here, we have investigated strong
resonant photon-magnon coupling at frequencies above 1 terahertz for the first
time in a prototypical room-temperature antiferromagnetic insulator, NiO,
inside a Fabry-P\'erot cavity. The cavity was formed by the crystal itself when
it was thinned down to an optimized thickness. By using terahertz time-domain
spectroscopy in high magnetic fields up to 25 T, we swept the magnon frequency
through Fabry-P\'erot cavity modes and observed photon-magnon anticrossing
behavior, demonstrating clear vacuum Rabi splittings exceeding the polariton
linewidths. These results show that NiO is a promising platform for exploring
antiferromagnetic spintronics and cavity magnonics in the terahertz frequency
range
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