The temperature, frequency, and voltage dependences of the dielectric properties of 0.93Pb(Fe1/2Nb1/2)O3–0.07PbTiO3 single crystals were investigated in the temperature range of 100–300 K. An anisotropic colossal dielectric response was observed when the probe of the AC field was along the [100] and [111] directions. One relaxation was detected in the [100] direction, while two relaxations were detected in the [111] direction. The activation energies of the relaxations are in the range of 0.155–0.190 eV, indicating that the relaxations are probably caused by 3d electrons hopping between Fe2+ and Fe3+. The origin of the anisotropic colossal dielectric response can be explained by a "two-hopping path" model.
In a preceding study, converting conventional tillage (ConvT) to conservation tillage (ConsT) was reported to decrease nitrogen (N) but to increase phosphorus (P) losses during snowmelt runoff. A field-scale study was conducted from 2004 to 2012 to determine if conversion of ConsT to rotational tillage (RotaT), where conservation tillage was interrupted by a fall tillage pass every other year, could effectively reduce P losses compared with ConsT. The RotaT study was conducted on long-term paired watersheds established in 1993. The ConvT field in the pair has remained under ConvT practice since 1993, whereas tillage was minimized on the ConsT field from 1997 until 2007. In fall 2007, RotaT was introduced to the ConsT field, and heavy-duty cultivator passes were conducted in the late fall of years 2007, 2009, and 2011. Runoff volume and nutrient content were monitored at the edge of the two fields, and soil and crop residue samples were taken in each field. Greater soil Olsen P and more P released from crop residue are likely the reasons for the increased P losses in the ConsT treatment (2004-2007) relative to the ConvT treatment (2004-2007). Analysis of covariance indicated that, compared with ConsT (2004-2007), RotaT (2008-2012) increased the concentrations of dissolved organic carbon (DOC) by 62%, total dissolved N (TDN) by 190%, and total N (TN) by 272% and increased the loads of DOC by 34%, TDN by 34%, and TN by 60%. However, RotaT (2008-2012) decreased soil test P in surface soil, P released from crop residue, and duration of runoff compared with ConsT (2004-2007) and thus decreased the concentrations of total dissolved P (TDP) by 46% and total P (TP) by 38% and decreased the loads of TDP by 56% and TP by 42%. In the Canadian Prairies, where P is a major environmental concern compared with N, RotaT was demonstrated to be an effective practice to reduce P losses compared with ConsT.
New therapeutic strategies are urgently needed to improve clinical outcomes in patients with multiple myeloma (MM). Daratumumab is a first-in-class, CD38 human immunoglobulin G1κ monoclonal antibody approved for treatment of relapsed or refractory MM. Identification of an appropriate dose regimen for daratumumab is challenging due to its target-mediated drug disposition, leading to time- and concentration-dependent pharmacokinetics. We describe a thorough evaluation of the recommended dose regimen for daratumumab in patients with relapsed or refractory MM.
Objectives: The aim of this review was to examine the prevalence, incidence and risk factors of chronic heart failure in the type 2 diabetic population. Methods: A systematic search of studies related to chronic heart failure (CHF) in the diabetic population was performed using medical databases. Results: 1) The prevalence of CHF in the diabetic population was approximately 10-23% in the large previously studied cohort. This was about three times higher than in nondiabetic control groups. 2) The incidence of CHF in diabetes varied greatly. It was influenced by the time of follow-up, the mean age of patients, the state of metabolic control and the complications of diabetes. The incidence of CHF in patients with diabetes was approximately two-fold greater than in the non-diabetic population. 3) The main risk factors of CHF in the type 2 diabetic population were age, hemoglobin A1c (HbA1c), coronary heart disease, hypertension, microalbuminuria and obesity. Conclusions: The prevalence and incidence of CHF were found to be high in the diabetic population, and the risk factors of CHF were somewhat different from those in the general population. Keywords: Prevalence, Incidence, Risk factors, Chronic heart failure, Diabetes, Systematic review
In the present study, the left anterior descending coronary arteries of mice under anesthesia were ligated, and the optimal surgical conditions for coronary artery ligation (CAL) in the establishment of a myocardial infarction (MI) mouse model were investigated. All mice that survived were sacrificed seven days subsequent to the successful surgery. Body weight, blood serum and heart tissues were obtained for further analysis or biochemical and histopathological examinations. The survival rate of the mice following the CAL procedure was 70%. The aspartate aminotransferase (AST), creatine kinase (CK) and lactate dehydrogenase (LDH) concentrations in the serum of the experimental mice were significantly increased compared with those of the control mice, which reflected the enzyme release from the infarcted myocardial cells. Histopathological examination showed different degrees of MI in the heart tissues of the experimental mice. The results indicate that an MI model in mice may be successfully established using CAL under the surgical conditions utilized in the present study. These conditions were cost effective and the results may be replicated by laboratories that are less well-equipped.
Objectives: To investigate the prevalence of depressive symptoms in patients with silicosis and its determinants. Methods: A cross-sectional cohort study was performed. About 121 patients with silicosis randomly selected from a case registry of a non-ferrous metal company and 110 controls completed the questionnaires of sociodemographic variables, Beck depression inventory (BDI) and lung function test. χ 2 test was performed to compare the prevalence of depressive symptoms between two groups. The relationship between the variables and depressive symptoms in patients with silicosis was assessed by performing the logistic regression analysis. Results: Prevalence of depressive symptoms in patients with silicosis was 27.3%, which was higher than the figure 7.3% in controls (χ 2 = 15.8, p < 001). Severe respiratory symptoms, severe impaired physical function, FEV1 < 50% predicted and (FVC)% predicted less than mean were significantly associated with the depressive symptoms (Odds ratio [OR] = 4.6, 5.9, 3.0 and 5.2, respectively). Conclusion: High prevalence of depressive symptoms was found in patients with silicosis. Respiratory symptoms, physical function and pulmonary functions were associated with depressive symptoms. Our findings provide evidence for physicians to screen for depressive symptoms in patients with silicosis.
Pb(Fe 1/2 Nb 1/2 )O 3 -PbTiO 3 (PFNT) is a multiferroic compound having electric and magnetic orders. To further explore the structural nature of ferroic characteristics in this material, the dielectric properties and structures of Pb(Fe 1/2 Nb 1/2 ) 1-x Ti x O 3 (x=0.07 and 0.48) single crystals were investigated by a combination of temperature-dependent dielectric spectra, XRD, Raman and x-ray absorption fine-structure (XAFS) spectra. Both samples exhibit a frequency-dependent dielectric anomaly, which is significantly correlated to the local structure differences.
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