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PurposeThis study extends research on one of the most frequently cited school leadership frameworks by examining the psychometric properties of the instrument designed to assess many of the practices included in that framework.Design/methodology/approachUsing data collected from 1,401 teachers the study examined the instrument’s measurement invariance, score reliabilities, as well as construct and predictive validities. Polytomous latent trait models (Many-Facet Rasch model), scale and principal component analysis using second-order Confirmatory Factor Analysis, and Structural Equation Modeling (SEM)-Path modelling were used for these purposes.FindingsFindings report levels of score reliability and valid score inferences. Results concerning the predictive validity of the instrument indicate a complex set of relations among the domains of leadership practices measured by the instrument, variables selected as mediators of leaders’ influence, and their direct and indirect effects on student learning.Research limitations/implicationsThis study provides researchers with a reliable and valid instrument for use in their future research. Data for the study were provided by elementary teachers in one US state. The extent to which results of the instrument are valid across different cultural and organizational settings remains to be determined.Practical implicationsLeadership developers may find the instrument useful for assessing the strengths and weaknesses of those participating in their programs while leaders themselves many find the instrument useful for self-diagnosis.Originality/valueThis study contributes to the development of school leadership measures by including Rasch modeling among the methods used for examining the instrument’s psychometric properties.

Information asymmetry and extreme events shocks can lead to the phenomenon of significant carbon market contagion. However, the existing studies mainly focus on the low-order moment of carbon price, making it difficult to reveal the risk contagion characteristic caused by irrational behaviors and policy shocks. This article takes market skewness and kurtosis into the research framework and constructs the FR, CS, and CK statistical model to detect the contagion in correlation channel, coskewness channel, and cokurtosis channel, respectively. The contribution of this article is to reveal the significant high-order moment contagion channel and strength of carbon market to its infected market under different market volatility trends. The results show significant contagion is widespread from the carbon market to its infected markets through the channels of coskewness and cokurtosis in different volatility trends. Additionally, the contagion strength in volatility rapid and slowly rise trend is generally higher than in the volatility rapid and slowly decline trend. That is to say, the shock of market irrationality and external events in the carbon market measured by the high-order moment contagion channels are essential risk factors that affect its infected markets. Those results convince that the acceptance of significant contagion sourced from the carbon market varies for different infected markets.

Over the past decade there has been increasing support for a role of the immune system in the development of hypertension. Our lab has previously reported that female spontaneously hypertensive rats (SHRs) have a blood pressure (BP)-dependent increase in anti-inflammatory renal regulatory T cells (Tregs), corresponding to lower BP compared with males. However, little is known regarding the mechanism for greater renal Tregs in females. The current study was designed to test the hypothesis that the greater relative abundance of renal Tregs in female SHR is due to greater Treg production. To test this hypothesis, T cell profiles were measured in the spleen by flow cytometry in male and female SHR at 5 and 14 weeks of age. Splenic Tregs did not differ between males and females, suggesting sex differences in renal Tregs is not due to differences in production. To assess the role of the spleen in sex differences in renal Tregs and BP control, rats were randomized to receive sham surgery (CON) or splenectomy (SPLNX) at 12 weeks of age and implanted with telemeters to measure BP. After 2 weeks, kidneys were harvested for flow cytometric analysis of T cells. Splenectomy increased BP in both sexes after 2 weeks. Renal Tregs decreased in both sexes after splenectomy, abolishing the sex differences in renal Tregs. In conclusion, splenic Tregs were comparable in male and female SHRs, suggesting that sex differences in renal Tregs is due to differences in renal Treg recruitment, not Treg production.

Impairments in insulin sensitivity can occur in patients with chronic kidney disease (CKD). Correction of metabolic acidosis has been associated with improved insulin sensitivity in CKD, suggesting that metabolic acidosis may directly promote insulin resistance. Despite this, the effect of acid or alkali loading on insulin sensitivity in a rodent model of CKD (remnant kidney) has not been directly investigated. Such studies could better define the relationship between blood pH and insulin sensitivity. We hypothesized that in remnant kidney rats, acid or alkali loading would promote loss of pH homeostasis and consequently decrease insulin sensitivity. To test this hypothesis, we determined the impact of alkali (2 wk) or acid (5–7 days) loading on plasma electrolytes, acid-base balance, and insulin sensitivity in either sham control rats, 2/3 nephrectomized rats, or 5/6 nephrectomized rats. Rats with 5/6 nephrectomy had the greatest response to insulin followed by rats with 2/3 nephrectomy and sham control rats. We found that treatment with 0.1 M sodium bicarbonate solution in drinking water had no effect on insulin sensitivity. Acid loading with 0.1 M ammonium chloride resulted in significant reductions in pH and plasma bicarbonate. However, acidosis did not significantly impair insulin sensitivity. Similar effects were observed in Zucker obese rats with 5/6 nephrectomy. The effect of renal mass reduction on insulin sensitivity could not be explained by reduced insulin clearance or increased plasma insulin levels. We found that renal mass reduction alone increases sensitivity to exogenous insulin in rats and that this is not acutely reversed by the development of acidosis. NEW & NOTEWORTHY Impairments in insulin sensitivity can occur in patients with chronic kidney disease, and previous work has suggested that metabolic acidosis may be the underlying cause. Our study investigated the effect of acid or alkali loading on insulin sensitivity in a rodent model of chronic kidney disease. We found that renal mass reduction increases the blood glucose response to insulin and that this is not acutely reversed by the development of acidosis.

Introduction Chronic vertebral basilar artery occlusion is one of the most common causes of ischemic stroke, which accounts for roughly 20% of all cases. However, the evidence for the precise clinical effect in treatment of the initial segment of chronic vertebral basilar artery occlusion is not sufficient. Aim To evaluate the feasibility and efficacy of endovascular therapy in the initial segment of chronic vertebral basilar artery occlusion. Material and methods This is a retrospective study based on data obtained from Lishui Hospital of Zhejiang University. We identified patients who underwent treatment for initial segment occlusion of the vertebral basilar artery from September 2014 to September 2018. Results Among a total of twenty-two subjects, 77.27% of them were men and the median age was 61 years old. The primary medical history of these patients included hypertension (15, 68.18%), hyperlipidemia (13, 59.09%), diabetes mellitus (11, 50.00%), and coronary artery disease (6, 27.27%). About 54.54% of the patients were current smokers. Successful recanalization was achieved in 86.36% of patients. Five cases of balloon dilatation were recanalized and fourteen cases were treated by balloon dilation combined with stent implantation. During the follow-up period, there were no recurrent cerebral ischemic events, including transient ischemic attack or stroke. Six (27.27%) arteries were found to exhibit angiographic re-stenosis. Conclusions The clinical effect of balloon dilatation or balloon dilatation combined with stenting in the treatment of chronic vertebral basilar artery occlusion in the beginning segment was feasible and safe.

Xueping Chen,1,2 Xiaoxue Liang,2 Jun Zhang,1,2 Liujing Chen,1,2 Jingping Sun,2 Xueli Cai2 1Zhejiang University, School of Medicine, Hangzhou, Zhejiang, 310005, People’s Republic of China; 2Department of Neurology, Lishui Hospital of Zhejiang University (Lishui Municipal Central Hospital), Lishui, Zhejiang, 323000, People’s Republic of ChinaCorrespondence: Xueli Cai; Jingping Sun, Department of Neurology, Lishui Hospital of Zhejiang University (The Central Hospital of Lishui), No. 289, KuoCang Street, Lishui, Zhejiang, 323000, People’s Republic of China, Tel +8613967059836 ; +860578-2285330, Email xueli_cai_official@126.com; lszxyysunjingping@yeah.netPurpose: Stroke-associated infection (SAI) is one of the most common post-stroke complications, which may lead to a relatively poor prognosis. This study aims to explore the potential relationship between serum calcium levels and SAI.Patients and Methods: This is a cross-sectional study involving 395 participants. SAI is a term that covers stroke-associated pneumonia (SAP), urinary tract infection (UTI), as well as other infections diagnosed during the first week after a stroke. Serum calcium levels were measured within 24 hrs of admission. To determine the association of serum calcium levels with the SAI, logistic regression models were calculated. An adjusted spline regression model was used to further confirm the relationship between the two.Results: Among the total patients, SAI occurred in 107 (27.1%) patients. Serum calcium was associated with SAI and was independent of the SAI risk factors for age, admission NIHSS score, and intravascular therapy [adjusted OR 0.040 (95% CI = 0.005– 0.291), p = 0.002]. Remarkably, this trend applies predominantly to serum calcium levels less than 2.25mmol/L (p= 0.005 for linearity).Conclusion: Serum calcium levels are associated with the risk of SAI, when serum calcium is below normal (2.25mmol/L), the risk of SAI increases as serum calcium levels decrease.Keywords: calcium homeostasis, stroke-associated infection, pneumonia, risk factors

We aimed to investigate the effectiveness of endovascular therapy (EVT) versus intravenous thrombolysis (IVT) in patients with basilar artery occlusion (BAO), based on the information of advanced imaging.We analyzed data of stroke patients with radiologically confirmed BAO within 24 hours. BAO subjects were categorized into "top-of-the-basilar" syndrome (TOBS) and other types. An initial infarct size of70ml and a ratio of ischemic tissue to infarct volume of ≥1.8 was defined as "target mismatch." The primary outcome was a good outcome, defined as a modified Rankin Scale score of 0 to 3 at 3 months. Propensity score adjustment and inverse probability of treatment weighting (IPTW) propensity score methods were used.Among 474 BAO patients, 93 (19.6%) were treated with IVT prior to EVT, 91 (19.2%) were treated with IVT alone, 95 (20.0%) were treated with EVT alone, and 195 (41.1%) were treated with antithrombotic therapy. In IPTW analyses, we found no benefit of EVT over IVT for good outcome in either TOBS patients (odds ratio = 1.08, 95% confidence interval [CI] = 0.88-1.31) or those with other types (odds ratio = 1.13, 95% CI = 0.94-1.36). However, in patients with other types, if there existed a target mismatch, EVT was independently related to good outcome (odds ratio = 1.46, 95% CI = 1.17-1.81).The "target mismatch profile" seems to be a possible candidate selection standard of EVT for those with other types of BAO. Future studies should separate TOBS from other types of BAO, and try to use advanced imaging. ANN NEUROL 2022;92:97-106.

Vascular congestion is common in ischemic acute kidney injury (AKI) and represents densely packed red blood cells (RBC) in the kidney circulation. In this study we tested the hypothesis that ‘vascular congestion directly promotes tubular injury’.Studies were performed in male and female Wistar-Kyoto rats. Vascular congestion and tubular injury were examined between renal venous clamping, arterial clamping and venous clamping of blood perfused and blood free kidneys. Vessels were occluded for either 15 or 45 minutes without reperfusion.We found that venous clamping resulted in greater vascular congestion than arterial clamping, particularly in the outer-medullary region (POur data demonstrate that congestion of the kidney results in the rapid, mass extravasation and uptake of RBCs by tubular cells causing toxic injury to the tubules. Tubular toxicity from extravasation of RBCs appears to be a major component of tubular injury in ischemic AKI which has not previously been recognized.

Noninvasive determination of the severity of parenchymal injury in acute kidney injury remains challenging. Edema is an early pathological process following injury, which may correlate with changes in kidney volume. The goal of the present study was to test the hypothesis that “increases in kidney volume measured in vivo using ultrasound correlate with the degree of renal parenchymal injury.” Ischemia-reperfusion (IR) of varying length was used to produce graded tissue injury. We first determined 1) whether regional kidney volume in rats varied with the severity (0, 15, 30, and 45 min) of warm bilateral IR and 2) whether this correlated with tubular injury score. We then determined whether these changes could be measured in vivo using three-dimensional ultrasound. Finally, we evaluated cumulative changes in kidney volume up to 14 days post-IR in rats to determine whether changes in renal volume were predictive of latent tubular injury following recovery of filtration. Experiments concluded that noninvasive ultrasound measurements of change in kidney volume over 2 wk are predictive of tubular injury following IR even in animals in which plasma creatinine was not elevated. We conclude that ultrasound measurements of volume are a sensitive, noninvasive marker of tissue injury in rats and that the use of three-dimensional ultrasound measurements may provide useful information regarding the timing, severity, and recovery from renal tissue injury in experimental studies.

The solubility of bisphenol A in 14 different pure solvents (N,N-dimethylformamide, formamide, acetone, 1,4-dioxane, cyclohexanone, ethyl acetate, methyl acetate, acetonitrile, ethanol, methanol, 1...

Rationale: Transjugular intrahepatic portosystemic shunt (TIPS) is mainly used to treat acute and chronic esophageal, gastric, and intestinal variceal bleeding and refractory ascites caused by portal hypertension. The most common complication of TIPS is the development of hepatic encephalopathy (HE). Fecal microbiota transplantation (FMT) is an emerging method for treating diseases by altering the intestinal flora. We present 2 cases of FMT that ameliorated liver function and HE after TIPS. Patient concerns: In this report, 2 patients with liver cirrhosis secondary to hepatitis B had recurrent Grade 2-3 HE after TIPS. Diagnosis: Two patients were diagnosed as having HE. Interventions: The 2 patients separately received 3 times of FMT. Outcomes: The liver function of both patients improved, the clinical symptoms were relieved, and the number of HE attacks decreased significantly after FMT. Lessons: FMT may be another effective way to treat HE, and is worthy of further research.

BACKGROUND Stenting appears to be a safe means of treatment for vertebral artery ostium stenosis with low complication rates and positive long-term effects, but the incidence of in-stent restenosis (ISR) after stenting is high. Different treatment strategies are applied for the revascularization of ISR; however, currently the optional approach is not recommended. The study was designed to investigate the feasibility, safety, and effectiveness of balloon-assisted angioplasty for the treatment of ISR after vertebral artery ostium stenosis. METHODS In this study, we included patients from the Department of Neurology, Lishui Hospital of Zhejiang University, who were treated with balloon-assisted angioplasty as a result of suffering from ISR after previously undergoing vertebral artery ostium stenting. We retrospectively analyzed the clinical and functional outcomes of the patients. RESULTS From January 2015 to December 2019, 11 patients were included in the study. The technical success rate reached 100% and the average operation time was 73 minutes. The Thrombolysis in Cerebral Infarction Score 2b-3 was acquired in all patients except 1 patient, who was presented with symptoms of hypoperfusion syndrome. The remaining 10 patients did not experience any intraoperative or postoperative complications. No restenosis, new cerebral infarction or transient ischemic attack were reported within 6 months of follow-up. CONCLUSION Balloon-assisted angioplasty could be feasible for the treatment of ISR after vertebral artery ostium stenting, however, more research is needed to confirm this.

The solubility of methyleneaminoacetonitrile in binary (ethanol+water, ethanol+2-propanol, ethanol+ n -butanol) solvents was measured by a laser dynamic method under p = 101.1 kPa at temperatures ranging from 278.15 K to 323.15 K. The solubility increased with increasing temperature at a given solvent composition; the solubility also increased with the increasing content of ethanol at a given temperature. The modified Apelblat equation, λh equation and Jouyban-Acree model were used to correlate the experimental solubility data, the values of RD and RMSD indicated that these models fit solubility data well. The calculated thermodynamic properties of Δ sol H ° , Δ sol S ° , Δ sol G ° showed that the dissolution process in binary solvents was endothermic and entropy-driven.

Purpose: This study tested a set of variables mediating school leadership’s influence on students referred to as “The four paths model.” Each path in the model includes variables with significant direct effects on student learning and which are malleable to practices included in an integrated model of effective school leadership. Research Design: Evidence for the study were responses to a survey by 1,779 teachers in 81 Texas elementary schools about the status of school leadership and all 13 variables on the four paths. Student achievement data were provided by results of state tests combining all subjects and all grades, while the count and percentage of students eligible for free or reduced-price lunch was used to estimate socioeconomic status. Confirmatory factor analysis, regression analysis, and structural equation modeling were used to analyze the data. Findings: Results uncovered a more nuanced and complex set of relationships among the four paths and their component variables than was specified in the original version of the model. School leadership significantly influenced student learning only through variables on one path, while variables on the other three paths influenced student learning only through their contribution to variables on that one path. Conclusions: Results point to the value of future research about the relationships among variables on the four paths, as well as efforts to identify latent variables among the observed variables in the study. Results of the study can be used by school leaders to more productively focus their school improvement efforts.

Purpose The purpose of this paper is to test the effects of nine district characteristics on student achievement, explored the conditions that mediated the effects of such characteristics and contributed to understandings about the role school-level leaders play in district efforts to improve achievement. Design/methodology/approach Data for the study were provided by the responses of 2,324 school and district leaders in 45 school districts to two surveys. Student achievement evidence was provided by multi-grade provincial measures of math and language achievement. The analysis of these data included calculation of descriptive statistics, confirmatory factor analysis and regression mediation analysis. Findings Seven of nine district characteristics contributed significantly to student achievement and three conditions served as especially powerful mediators of such district effects. The same three conditions, as well as others, acted as significant mediators of school-level leader effects on achievement, as well. Practical implications District characteristics tested in the study provide a powerful framework for guiding the district improvement work of senior educational leaders. The organizational improvement efforts of both district and school leaders would be substantially enhanced by a better understanding of how to diagnose and improve the status of those conditions acting as significant mediators of the effects of both district and school leadership on student achievement. Originality/value This is one of a very few large-scale quantitative studies examining the extent to which characteristics frequently identified by district effectiveness research explain variation in student learning. It is also one of the very few studies identifying classroom, school and family variables that mediate district effects on such learning. The study also adds to a growing body of evidence about variables which mediate school leaders’ effects on such learning.

Do school district central offices and school principals have the same level of influence on school decisions? What does the district–principal power relationship look like? These two questions are discussed but are rarely examined in the literature. Based on a nationally representative sample from the 2007-2008 Schools and Staffing Survey data, we explored these two questions. Specifically, we applied the paired samples t test to compare the district central offices’ and school principals’ influences and applied the multilevel modeling method to estimate the power relationship. We found that (a) on average, districts and principals had the same level of influence on establishing curriculum, whereas school principals had higher influence on the other six decision areas examined (performance standards, teachers’ professional development programs, evaluating teachers, hiring teachers, discipline policies, and school budget), and (b) a tight coupling power relationship between district central offices and school principals was identified for the three areas related to the technical core of schools (performance standards, establishing curriculum, and teachers’ professional development programs), a loose coupling power relationship was revealed for the personnel (hiring and evaluating teachers) and budget areas, while a decoupling power relationship was found for discipline policy decisions. Discussions and implications for school leadership and policy were included in this study.

The solubility of methyleneaminoacetonitrile in binary solvents (ethanol+methanol, 2-propanol+methanol, n‑butanol+methanol) was measured by a laser dynamic method under atmospheric pressure at temperatures ranging from 278.15 K to 323.15 K. The solubility of methyleneaminoacetonitrile in binary solvents increased with increasing temperature and the content of methanol. In addition, Hansen solubility parameters (HSP) were used to explain and predict the solubility behavior. The experimental solubility data in binary solvents were correlated by the modified Apelblat equation, λh equation, Jouyban-Acree model, and Sun model. The values of RD and RMSD indicated that these models fit the solubility data well in binary solvents. The thermodynamic properties (ΔsolH°, ∆solS°, ∆solG°, %ξH, %ξTS) of the solution were calculated from the van't Hoff equation, and the dissolution process was endothermic, and the force of the dissolution process was entropy-driven.

The solubility of 2-cyanoacetamide in N,N-dimethylformamide, acetone, acetonitrile, methanol, methyl acetate, tetrahydrofuran, ethanol, ethyl acetate, n-propanol, n-butanol, trichloromethane, dichl...

Based on research evidence from the origins of transformational leadership in the seventies, the author claims that this approach is the one that presents the highest incidence in the policies of promotion of school leadership and the one that has the largest number of empirical studies carried out. His chapter analyzes the evidence regarding the strong influence of transformational leadership of managers in the emotional state of teachers, their job satisfaction and their commitment to school, as well as its relevant effect on the practices that teachers perform, reviewing its effect regarding the academic results of the students, which would also affect, although in a milder way, through the teachers. Resumo Com base em evidências de pesquisas sobre as origens da liderança transformacional nos anos setenta, o autor assegura que essa abordagem é a que apresenta maior incidência nas políticas de promoção de liderança escolar e aquela que possui o maior número de estudos empíricos realizados. Seu artigo analisa evidências sobre a forte in?uência transformacional da liderança dos gestores no estado emocional, na satisfação com o trabalho e no compromisso dos professores com a escola, bem como seu efeito relevante nas práticas que os professores realizam, revendo seu efeito nos resultados acadêmicos dos alunos, o que também afetaria, ainda que de forma mais branda, através dos professores. Resumen A partir de la evidencia de investigaciones desde los orígenes del liderazgo transformacional en los años setenta, la autora asegura que este enfoque es el de mayor incidencia en las políticas de fomento del liderazgo directivo escolar y el que tiene el mayor número de estudios empíricos realizados. Su capítulo analiza la evidencia respecto a la fuerte incidencia del liderazgo transformacional de los directivos en el estado emocional de los docentes, su satisfacción laboral y su compromiso con la escuela, así como su efecto relevante en las prácticas que los docentes realizan, revisando su efecto respecto los resultados académicos de los alumnos, en los que también incidiría, aunque de modo más leve y a través de los docentes.

Exposure to fine particulate matter (PM2.5) can induce oxidative stress and proinflammatory cytokine production, which are central for the induction of PM2.5-mediated adverse effects on public health. Nuclear factor kappa B (NF-κB) signaling is essential for inflammation. The subcellular distribution of thioredoxin (Trx) is related to the activation of NF-κB, but the mechanism involved is unclear. In the current study, we focused on the relationship between the antioxidant Trx and NF-κB in human bronchial epithelial cells (BEAS-2B) after PM2.5 exposure. We inhibited the nuclear translocation of Trx by cHCEU (4-cyclohexyl-[3-(2-chloroethyl)ureido]benzene) and subsequently increased the transcriptional activity of Nrf2 to upregulate the expression of Trx by t-BHQ. Our data suggest that PM2.5 exposure induces the activation of NF-κB and the expression of the downstream proinflammatory cytokines IL-1, IL-6, IL-8 and TNF-α in BEAS-2B cells. CHCEU alleviates inflammatory cytokines by blocking Trx nuclear translocation and inhibits the DNA binding activity of NF-κB. T-BHQ could promote the transcriptional activity of Nrf2 but failed to alleviate the production of inflammatory cytokines. Furthermore, the synergistic effect of t-BHQ and cHCEU on alleviating PM2.5-induced inflammation is more effective than the use of cHCEU alone. Our findings characterize the underlying molecular mechanisms of proinflammatory responses induced by PM2.5 and show that the nuclear translocation and accumulation of Trx in nuclei play important roles in PM2.5-induced NF-κB activation and proinflammatory responses.

Background: Tibetans are one of the oldest ethnic groups in China and South Asia. Tibetans have a unique lifestyle and a long history, which leads to the particularity of the composition and function of their gut microflora. Tibetans in the Minjiang River basin have gradually increased their migration to the Chengdu Plain in recent years. Based on the analysis of 1059 Tibetans in the Minjiang River basin at an altitude of 500-4001 m, we analyzed the characteristics of the gut microbiome and further elaborated the main factors affecting the succession of the gut microbiome in the Tibetan population.Results: Our study found that the dominant phyla of the Tibetan population were Bacteroidetes and Firmicutes, and the main genera were Prevotella and Bacteroides. To further study the factors affecting the gut microbial composition of the Tibetan population, 115 total parameters of 7 categories were evaluated. The results showed that altitude was the most important factor affecting the variation in the microbial community in the Tibetan population, and the change in altitude promoted the succession of the gut microbial community. In the process of migration from high altitudes to the plain, the gut microbial composition of late immigrants was similar to that of plateau aborigines, while that of early immigrants was similar to that of plain aborigines. Migration to Tibet is related to the loss of indigenous gut microbial community species. In addition, from low altitude to high altitude, the similarity of the microbial community with the high-altitude population increased with the reproduction of offspring after marriage. Changes in these microbials will affect the metabolism, disease incidence and cell function of the Tibetan population. The other two sets (AGP and Z208) of altitude data also showed the impact of altitude on the microbial community.Conclusions: This is the first large-scale study on the factors influencing the gut microflora in a Tibetan population. Our study confirmed that altitude change is the most important factor affecting the distribution of the microflora in the Tibetan population and provided abundant and unique data to explore the interaction of impact parameter-gut microbiome-host function and disease.