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Degradation of lithium trivanadate (LixV3O8) cathodes has been widely reported in the literature, but studies have offered little insight towards developing a detailed understanding of the evolution of the active material, and have been inconclusive as to the root cause of degradation. Here, we refit a validated physics-based model to discharge curves over the course of cycling at C/5, and use the evolution of the model parameters to track evolution of the cathode. A regularization penalty for adjusting model parameters from the validated model is introduced as a framework to identify which model parameters can explain a significant portion of the observed change in the voltage profile over the course of cycling. SEM reveals that lithium trivandate particles fracture upon cycling at C/5, consistent with the results of the parameter estimation, deactivation of lithium trivanadate and faster diffusion of lithium within the active particles. The physics-based model is then used to design modified cycling protocols which identify the phase transformation during discharge of lithium trivanadate as the driver of the particle fracture and capacity fade. [ABSTRACT FROM AUTHOR]

MIB-1 is a cell proliferation marker and has previously been investigated as a diagnostic or prognostic indicator of malignancy. Previous studies have investigated MIB-1 index and clinicopathological factors in relation to prognosis of patients with esophageal cancer, with conflicting results. The aim of this study is to assess the prognostic significance ofMIB-1 index in patients with thoracic esophageal squamous cell carcinoma. A total of 78 patients who underwent R0-esophagectomy for thoracic esophageal squamous cell carcinoma were enrolled in this study. Preoperatively, 29 patients underwent chemotherapy, six underwent chemoradiotherapy, and the remaining did not undergo any preoperative therapy. The MIB-1 labeling index was reported by counting 500 tumor cells in the hot spots of nuclear labeling. Correlations between MIB-1 index, clinicopathological factors, and relapse-free survival (RFS) were investigated. The mean MIB-1 index was 39.3 ± 21.0 (range: 0–91.3). There was no significant correlation between clinicopathological factors and MIB-1 index in the study patients, irrespective of whether they underwent preoperative therapy. Univariate analysis revealed no significant association between MIB-1 index and RFS. However, depth of tumor invasion, lymph node metastasis and stage, all showed a significant correlation to RFS. Multivariate analysis of RFS revealed that stage was the only significant factor. Conversely,MIB-1 index was not significantly related to RFS (p = 0.41). In conclusion, MIB-1 index is unlikely to be a significant prognostic indicator for esophageal cancer. [ABSTRACT FROM AUTHOR]

We proposed a new separation and recovery process for RE metals from Nd magnet scraps using molten salt electrolysis. The present study focused on the electrochemical formation of RE–Ni (RE = Dy, Nd, Pr) alloys in a molten LiCl–KCl system at 723 K. Cyclic voltammetry was conducted using a Ni electrode in molten LiCl–KCl–RECl3systems at 723 K. In the negative scan for the DyCl3added system, a large cathodic current was observed from 0.70 V (vs. Li+/Li) as a result of the formation of Dy–Ni alloys. In contrast, large cathodic currents as results of the formation of Nd–Ni and Pr–Ni alloys were observed from 0.60 V. On the basis of these results, an alloy sample was prepared by potentiostatic electrolysis at 0.65 V for 1 h using a Ni plate cathode in a molten LiCl–KCl–DyCl3–NdCl3–PrCl3system. The mass ratio of Dy/Nd+Pr in the alloy sample was found to be 50 by ICP-AES. Finally, a Dy permeation experiment was conducted with a new electrolytic cell. [ABSTRACT FROM PUBLISHER]

The effect of frequency on giga-cycle fatigue properties was investigated in smooth and 0.3 mm-hole-notched specimens at three heats (Heats A, B, and C) for a 900 MPa-class Ti-6Al-4V alloy. Fatigue tests were performed at frequencies of 120 Hz, 600 Hz, and 20 kHz using electromagnetic resonance, high-speed servohydraulic, and ultrasonic fatigue testing machines, respectively. Heats A and B developed internal fractures, and in these cases, frequency effects were negligible. On the other hand, Heat C developed only surface fractures. In this case, high-frequency tests showed a higher fatigue strength, indicating frequency effects were not negligible. The tests using the notched specimens showed almost no frequency effects regardless of the heat. The frequency effects observed in the cases of surface fracture were believed to be related to a delay in local plastic deformation in response to high-frequency loading, since temperature increases in these specimens were successfully suppressed. The delay in the plastic deformation was observed to be reduced in the notched specimens because of stress concentration and limitation in the plastic deformation zone. In turn, the significant conclusion of this research is that high-frequency tests can be applied not only to internal fractures but also to notch problems, but are not applicable to surface fractures of smooth specimens. [ABSTRACT FROM AUTHOR]

Structural studies have been carried out on Ag2V4O11 (silver vanadium oxide, SVO) and LixAg2V4O11, lithiated SVO with x = 0.72, 2.13, and 5.59 using nuclear magnetic resonance (NMR) and X-ray absorption spectroscopy (XAS). Lithium-7 NMR indicates the formation of a solid electrolyte interphase layer on the x = 0.72 sample and lithium intercalation into both octahedral and tetrahedral sites in the SVO lattice, and that most but not all of the Ag (I) is reduced prior to initiation of V(V) reduction. Vanadium-51 NMR studies of SVO and lithiated SVO show decreased crystallinity with increased lithiation, as previously reported. Silver XAS studies indicate the formation of metallic silver crystallites in all the lithiated samples. A comparison of X-ray absorption near edge spectroscopy spectra for vanadium in these samples with those of reference compounds shows that some reduction of vanadium (V) occurs in the lithiated SVO with x = 0.72 and increases with further lithiation leading to the formation of V(IV) and V(III) species. The results of this study indicate that vanadium(V) reduction occurs in parallel with silver (I) reduction during the initial stages of SVO lithiation, leading ultimately to the formation of vanadium (IV) and (III) species with further lithiation. [ABSTRACT FROM AUTHOR]

Background: The Sauvé-Kapandji procedure has become popular for the treatment of disorders of the distal radioulnar joint in patients with rheumatoid arthritis, but this procedure is impossible to perform in patients with poor bone quality in the distal part of the ulna. We have modified the procedure for patients with poor bone quality in the distal part of the ulna. The modified procedure involves resecting the distal part of the ulna, making a drill-hole in the ulnar cortex of the distal part of the radius, rotating the resected portion of the ulna 90 degrees, inserting it into the distal part of the radius, and fixing it at that site with use of an AO cancellous-bone screw. In the present report, we describe the new operative technique and report the results after a minimum duration of follow-up of three years.Methods: This operation was performed in fifty-six patients (sixty-six wrists) with rheumatoid arthritis. The mean age at the time of the operation was 59.3 years. The mean duration of follow-up was forty-eight months. Patients were evaluated in terms of wrist pain, grip strength, and range of motion. Radiographic evaluation included calculation of the carpal translation index to assess the extent of ulnar translation of the carpus.Results: Osseous union was achieved in all cases. Wrist pain resolved or decreased in all patients. The mean total range of forearm rotation increased from 144 degrees preoperatively to 167 degrees at the time of the most recent follow-up (p < 0.01). The mean carpal translation index did not change after the operation.Conclusions: The modified Sauvé-Kapandji procedure results in rigid fixation of the grafted bone. The technique provides sufficient osseous support of the carpus even in patients with rheumatoid arthritis and poor bone quality in the distal part of the ulna. [ABSTRACT FROM AUTHOR]

Calcifying tendinitis of rotator cuff tendons is a common and painful condition caused by ectopic calcification in humans. To examine the involvement of osteopontin (OPN), a potent regulator of calcium deposition on connective tissues, localization and expression of OPN protein and messenger (m)RNA were investigated in human tissue samples of calcified rotator cuff tendons. Immunohistochemistry demonstrated that OPN was localized in cells surrounding the calcified area. OPN was localized in two distinct cell types, i.e., fibroblast-like cells negative for CD68 and tartrate-resistant acid phosphatase (TRAP) and multinucleated macrophages positive for CD68 and TRAP. In situ hybridization revealed that the mRNA expression of OPN in these cells coincided with the immunohistochemistry results, and these results were supported by reverse transcriptase polymerase chain reaction analysis using human OPN-specific oligonucleotides. Cells located away from the calcified area did not express OPN. The present findings indicate the involvement of OPN in the process of calcification of rotator cuff tendons and suggest that OPN plays a role in such painful disorders through the actions of at least two cell types. [ABSTRACT FROM AUTHOR]

A Raman lidar with a deep ultraviolet laser was constructed to continuously monitor water vapor distributions in the atmospheric boundary layer for twenty-four hours. We employ a laser at a wavelength of 266 nm and detects the light separated into an elastic backscatter signal and vibrational Raman signals of oxygen, nitrogen, and water vapor. The lidar was encased in a temperature-controlled and vibration-isolated compact container, resistant to a variety of environmental conditions. Water vapor profile observations were made for twelve months from November 24, 2017, to November 29, 2018. These observations were compared with collocated radiosonde measurements for daytime and nighttime conditions.