ABSTRACT
A layered Li[NixCoyMn1-x-y]O2 (NCM)-based cathode is preferred for its high theoretical specific capacity. However, the two main issues that limit its practical application are severe safety issues and excessive capacity decay. A new electrode processing approach is proposed to synergistically enhance the electrochemical and safety performance. The polyimide's (PI) precursor is spin-coated on the LiNi0.5Co0.2Mn0.3O2 (NCM523) electrode sheet, and the homogeneous sulfonated PI layer is in situ produced by thermal imidization reaction. The PI-spin coated (PSC) layer provides improvements in capacity retention (86.47% vs 53.77% after 150 cycles at 1 C) and rate performance (99.21% enhancement at 5 C) as demonstrated by the NCM523-PSC||Li half-cell. The NCM523-PSC||graphite pouch full cell proves enhanced capacity retention (76.62% vs 58.58% after 500 cycles at 0.5 C) as well. The thermal safety of the NCM523-PSC cathode-based pouch cell is also significantly improved, with the critical temperature of thermal safety T1 (the beginning temperature of obvious self-heating temperature) and thermal runaway temperature T2 increased by 60.18 and 44.59 °C, respectively. Mechanistic studies show that the PSC layer has multiple effects as a passivation layer such as isolation of electrode-electrolyte contact, oxygen release suppression, solvation structure tuning, and the decomposition of carbonate solvents as well as LiPF6 inhibition. This work provides a new path for a cost-effective and scalable design of electrode decoration with synergistic safety-electrochemical kinetics enhancement.
ABSTRACT
Learning transfer is widely present in the learning of all kinds of knowledge, skills and social norms, and is one of the important phenomena of learning, and the reasonable use of transfer is conducive to improving the learning effect of students and the quality of teaching. This study starts from the data of college students' academic performance, takes real students' academic performance as a sample, measures the relevance of courses through students' academic performance, constructs various networks of learning transfer, and studies the topology and evolution of the networks to clarify the essential laws of learning transfer and put forward suggestions for the optimization of teaching strategies. Finally, using complex network analysis to analyze and mine the data on college students' academic performance, the article quantifies the overall structure of the courses and their hidden connections in a global and dynamic manner, and discovers the inheritance relationship between the courses, the clustering characteristics and the basic pattern of learning transfer. It also provides a platform for exploring the differences in the course structure of different majors and the learning transfer of male and female students.
Subject(s)
Physical Education and Training , Transfer, Psychology , Female , Humans , Models, Theoretical , Sports , StudentsABSTRACT
OBJECTIVE: This study aimed to investigate the changes and significance of microRNA155 levels in serum of patients with cerebral small vessel disease (CSVD). METHODS: Thirty patients with CSVD who met the inclusion criteria were selected and divided into eight patients with lacunar infarction (LI) group and 22 patients with multiple lacunar infarction (MLI) combined with white matter lesions (WML) group according to the results of head magnetic resonance imaging (MRI). Thirty samples from healthy volunteers without abnormalities after head MRI examination were selected as the control group. The levels of serum microRNA155 in each group were determined by real-time polymerase chain reaction, and the correlation between microRNA155 in the serum of patients with CSVD and the increase of imaging lesions was analyzed by Spearman correlation analysis. RESULTS: Compared with the control group, the serum microRNA155 level in the LI group, MLI combined with WML group increased, the difference was statistically significant (p<0.05); serum microRNA155 level was positively correlated with the increase of imaging lesions (p<0.05). CONCLUSION: The change of serum microRNA155 level in patients with CSVD may be one of its self-protection mechanisms, and the intensity of this self-protection mechanism is positively correlated with the number of CSVD lesions.
ABSTRACT
RATIONALE: Tolvaptan, an oral vasopressin V2 receptor antagonist, is a new approach for the treatment of adult patients with the syndrome of inappropriate antidiuresis (SIADH). However, dose-dependent side effect including rapid increase in serum sodium levels and liver injury, and the expensive price limit the long-term use of tolvaptan. We report a case of SIADH patient treated with intermittent lower dose of tolvaptan combined with fluid restriction. PATIENT CONCERNS: A 60-year-old woman presented of nausea and vomiting, dizzy and amaurosis, and transient disturbance, after a week of persistent diarrhea. DIAGNOSIS: Diagnosis of SIADH was based on severe persistent hyponatremia, decreased plasma osmolality, raised urinary sodium excretion, and the absence of other causes. INTERVENTIONS: She was given the treatment of tolvaptan 15âmg once daily, and experienced tolvaptan-related side effects including thirst and dry mouth, polyuria, and dizziness. Then, single dose of tolvaptan was reduced from 15 to 7.5âmg, and the interval between medication was gradually prolonged from 24 to 72âhours. Meanwhile, serum sodium was negatively correlated with the amount of daily water intake in interval days, so daily water intake of the patient was restricted to 1500 mL in interval days. OUTCOMES: Serum sodium was maintained within the normal range, 137 to 141âmmol/L without liver damage. LESSONS: For patients with chronic SIADH, the tolvaptan dose should be individualized, and the regimen of intermittent lower dose of tolvaptan combined with fluid restriction maybe an effective choice.
Subject(s)
Antidiuretic Hormone Receptor Antagonists/administration & dosage , Fluid Therapy/methods , Inappropriate ADH Syndrome/therapy , Tolvaptan/administration & dosage , Combined Modality Therapy , Female , Humans , Inappropriate ADH Syndrome/blood , Middle Aged , Sodium/blood , Treatment OutcomeABSTRACT
PURPOSE: Insulin autoimmune syndrome (IAS) is a relatively rare cause of hypoglycemia characterized by endogenous hyperinsulinism and autoantibodies against endogenous insulin despite no prior exposure to exogenous insulin. We present a series of IAS cases and describe the clinical characteristics of these cases. METHODS: The medical records of inpatients with the final diagnosis of IAS were collected from August 2007 to August 2017 in Peking Union Medical College Hospital. Clinical characteristics and laboratory test results were summarized. The results of serum glucose, insulin, true insulin, and C-peptide testing during 5-h oral glucose tolerance tests were also summarized. Circulating immune complexes were assessed qualitatively by precipitation with polyethylene glycol (PEG) in some patients. FINDINGS: Sixteen patients were included in this study. Insulin autoimmune antibody test results were found positive in 12 patients and weakly positive in 1 patient. Nine patients had an insulin to C-peptide molar ratio >1, whereas 6 patients had an insulin to C-peptide molar ratio <1. Circulating immune complexes were verified in all 4 patients who had been assessed with PEG. During 5-h oral glucose tolerance tests, the C-peptide level responded earlier to the glucose tolerance and had a shorter peak value period compared with insulin, although C-peptide's fluctuation still lagged behind the glucose fluctuation. Three patients presented with self-limited disease courses or limited disease course after discontinuing use of the sulfhydryl group drugs. Some patients' symptoms were relieved after small frequent meals, and some were relieved after taking acarbose. Only 3 patients took glucocorticoids as the anti-immune therapy. IMPLICATIONS: The insulin to C-peptide molar ratios were not consistently >1 in patients with confirmed diagnoses of IAS in our study, which suggested the low sensitivity of insulin to C-peptide molar ratio to detect IAS. The therapy in our study also revealed the self-limited disease course of IAS, and despite the effectiveness of anti-immunity therapy, convenient therapy, such as frequent small meals and adding acarbose, performed well in many patients.
Subject(s)
Autoantibodies/immunology , Autoimmune Diseases/immunology , Insulin Antibodies/immunology , Insulin/immunology , Acarbose/therapeutic use , Adult , Aged , Aged, 80 and over , Autoimmune Diseases/drug therapy , C-Peptide/metabolism , Child , Female , Glucocorticoids/therapeutic use , Glucose Tolerance Test , Humans , Hypoglycemia/drug therapy , Hypoglycemia/etiology , Male , Middle Aged , Syndrome , Young AdultABSTRACT
BACKGROUNDS: Cardiac autonomic neuropathy is a common but always overlooked. More convenient diagnostic methods are needed. HYPOTHESIS: Cardiac autonomic neuropathy risk score evaluated by SUDOSCAN has a fine diagnostic efficacy detecting cardiac autonomic neuropathy. METHODS: This is a cross-sectional study among patients with diabetes mellitus. Subjects undertook SUDOSCAN tests and cardiac autonomic reflex tests, including heart rate variability due to Valsalva maneuver, heart rate response due to deep breathing and heart rate response due to standing up. Presenting 2 abnormal results was defined as cardiac autonomic neuropathy. RESULTS: Subjects with cardiac autonomic neuropathy has significantly higher cardiac autonomic neuropathy risk score (32.88±1.60 vs 27.64±1.24,P = 0.010). Cardiac autonomic neuropathy risk score was correlated significantly with the heart rate response due to deep breathing(P = 0.004). Multiple regression analysis including significant variables showed an independent association of cardiac autonomic neuropathy risk score and heart rate response due to deep breathing (P = 0.031) and age (P = 0.000). In receiver operating characteristic curve analysis evaluating the relationship between cardiac autonomic neuropathy risk score and cardiac autonomic neuropathy, The cut-off value was 20.5, with the sensitivity of 90.48%, the specificity of 29.5%, and the positive predictive value of 46.9%. In two-step diagnostic methods, Setting 20.5 as the cut-off value of cardiac autonomic neuropathy risk score and abnormal heart rate response due to standing up as the second diagnostic step's positive result, and setting 16.5 as the cut-off value of cardiac autonomic neuropathy risk score and abnormal heart rate response due to deep breathing as the second diagnostic step's positive result, both achieved good diagnostic efficacy. CONCLUSION: Cardiac autonomic neuropathy risk score evaluated by SUDOSCAN is a good screening test for cardiac autonomic neuropathy. The two-step diagnostic methods could be considered as surrogate diagnostic methods.