2,027 research outputs found
Structural, thermal and magnetic properties of barium-ferrite powders substituted with Mn, Cu or Co and X (X = Sr and Ni) prepared by the sol-gel method
In this study, Ferrite A (undoped barium hexaferrite), Ferrite B (MnCuNi-doped barium hexaferrite), Ferrite C (MnCuSr-doped barium hexaferrite), Ferrite D (MnCoNi-doped barium hexaferrite) and Ferrite E (MnCoSr-doped barium hexaferrite) powders were prepared by sol-gel processing. The produced powders were calcined at 550 °C for 6 h and sintered at 1000 °C for 5 h to obtain the required phases. The powders were characterized by differential thermal analysis/thermogravimetric analysis (DTA/TG), X-ray diffractometry (XRD) and scanning electron microscopy (SEM), and vibrating-sample magnetometry (VSM). The XRD patterns indicated that the pure barium ferrite phase was not obtained. The presence of M-type BaFe 11.6Mn 0.4O 19 was confirmed in the Ferrite B and Ferrite D patterns. In the Ferrite C pattern, there were the phases of BaFe 12O 19, Ba 2Cu 2Fe 12O 22 (X or Z-type) and Sr 3Fe 2O 6.16. The Ba 0.5Sr 0.5Fe 12 phase was easily observed in the Ferrite E pattern. The results showed that the dopant materials significantly change the particle shape of Ferrite A powders, but also lower the value of the coercivity. A higher saturation magnetization was observed for the Ferrite D powder
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Quiet and blessed: rural tourism experience and visitor satisfaction in the shadow of Covid-19 and beyond
Rural tourism has an increasing share of the country's tourism income and significantly contributes to the rural economy. Intensive research has been conducted on how Covid-19 affects the tourism industry and the challenges and opportunities the sector face. Although the rise of rural tourism is frequently highlighted post-Covid-19, research examining the satisfaction levels of visitors involved in rural tourism is almost nonexistent. The study's main aim is to determine customers' satisfaction levels from rural activities in and around the İznik District of Bursa province and to recommend improvement. We obtained data from a structured survey conducted with 408 people who visited İznik at least once. SPSS 23 program was also used to analyze the data obtained. Results show that visitors' satisfaction with nature and the environment is above average, and their satisfaction with the services provided is below average. The most critical dissatisfaction was the increasing environmental pollution, the loss of natural beauty, the local government's inability to do the necessary cleaning and maintenance work, and the lack of introductory information in places with historical and natural characteristics. Participants wanted to stay in caravans and tents rather than hotels and suggested expanding and improving those facilities. They suggested that local textures are preserved, and more local food and beverages are offered. The suggestion shows that visitors demand integrating more with nature, local life and historical texture
Compressive sensing-based robust off-the-grid stretch processing
Classical stretch processing (SP) obtains high range resolution by compressing large bandwidth signals with narrowband receivers using lower rate analogue-to-digital converters. SP achieves the resolution of the large bandwidth signal by focusing into a limited range window, and by deramping in the analogue domain. SP offers moderate data rate for signal processing for high bandwidth waveforms. Furthermore, if the scene in the examined window is sparse, compressive sensing (CS)-based techniques have the potential to further decrease the required number of measurements. However, CS-based reconstructions are highly affected by model mismatches such as targets that are off-the-grid. This study proposes a sparsity-based iterative parameter perturbation technique for SP that is robust to targets off-the-grid in range or Doppler. The error between reconstructed and actual scenes is measured using Earth mover's distance metric. Performance analyses of the proposed technique are compared with classical CS and SP techniques in terms of data rate, resolution and signal-to-noise ratio. It is shown through simulations that the proposed technique offers robust and high-resolution reconstructions for the same data rate compared with both classical SP- and CS-based techniques. © 2017, The Institution of Engineering and Technology
Psychometric properties of the Internalized Stigma of Mental Illness (ISMI-10) scale in a Dutch sample of employees with mental illness
BACKGROUND: Internalized stigma can have numerous negative effects on the well-being and employment of people with mental illness. Brief, valid, and reliable measures are needed to get a better understanding of self-stigmatization. The aim of this study is to translate the brief version of the Internalized Stigma of Mental Illness (ISMI-10) scale into a Dutch version and to assess the reliability and validity of this Dutch version in a sample of employees with mental illness. METHODS: The ISMI-10 was translated into Dutch using the forward-backward translation procedure. The sample consisted of 161 employees with mental illness. Internal consistency was evaluated and the retest reliability was tested with 68 respondents. The construct validity was evaluated by testing convergent and divergent validity. RESULTS: The Dutch ISMI-10 showed good internal consistency (α = 0.83) and good test-retest reliability (r = 0.73). The Dutch ISMI-10 demonstrated excellent convergent validity; high correlations were found between the Dutch ISMI-10 and hope (r = -0.54), anxiety and depression (r = 0.59), self-esteem (r = -0.56), and empowerment (r = − 0.59). Acceptable divergent validity was indicated; small correlations were found between the Dutch ISMI-10 and the physical functioning subscale (r = -0.27) and the role limitation due to physical problems subscale (r = -0.21), and medium correlations were found between the Dutch ISMI-10 and the general health subscale (r = -0.36). CONCLUSION: The Dutch ISMI-10 demonstrated adequate psychometric properties for assessing internalized stigma and can be used by researchers in Dutch speaking countries to get a better understanding of self-stigmatization among people with mental illness. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12888-022-04284-5
Dietary L-arginine supplementation reduces Methotrexate-induced intestinal mucosal injury in rat
<p>Abstract</p> <p>Background</p> <p>Arginine (ARG) and nitric oxide maintain the mucosal integrity of the intestine in various intestinal disorders. In the present study, we evaluated the effects of oral ARG supplementation on intestinal structural changes, enterocyte proliferation and apoptosis following methotrexate (MTX)-induced intestinal damage in a rat.</p> <p>Methods</p> <p>Male rats were divided into four experimental groups: Control rats, CONTR-ARG rats, were treated with oral ARG given in drinking water 72 hours before and 72 hours following vehicle injection, MTX rats were treated with a single dose of methotrexate, and MTX-ARG rats were treated with oral ARG following injection of MTX. Intestinal mucosal damage, mucosal structural changes, enterocyte proliferation and enterocyte apoptosis were determined 72 hours following MTX injection. RT-PCR was used to determine bax and bcl-2 mRNA expression.</p> <p>Results</p> <p>MTX-ARG rats demonstrated greater jejunal and ileal bowel weight, greater ileal mucosal weight, greater ileal mucosal DNA and protein levels, greater villus height in jejunum and ileum and crypt depth in ileum, compared to MTX animals. A significant decrease in enterocyte apoptosis in the ileum of MTX-ARG rats (vs MTX) was accompanied by decreased bax mRNA and protein expression and increased bcl-2 protein levels.</p> <p>Conclusions</p> <p>Treatment with oral ARG prevents mucosal injury and improves intestinal recovery following MTX- injury in the rat.</p
The Impact of Previous Ureteroscopic Tumor Ablation on Oncologic Outcomes After Radical Nephrouretectomy for Upper Urinary Tract Urothelial Carcinoma
We investigated whether a history of endoscopic tumor ablation impacts oncologic outcomes after radical nephroureterectomy (RNU) for upper urinary tract urothelial carcinoma (UTUC). Using a multi-institutional database that contained patients who were treated with RNU, oncologic outcomes were assessed according to history of ureteroscopic tumor ablation. Disease-free survival (DFS) and cancer-specific survival (CSS) were estimated using the Kaplan-Meier survival analysis. Multivariate Cox regression analyses were performed to determine independent predictors of disease recurrence and cancer-specific mortality after RNU. The study included 1268 patients, 853 men and 415 women, with a mean age of 67.5 years (range 32-94 y) and 52.8 months median follow-up after RNU. A total of 175 (13%) patients underwent RNU after endoscopic tumor ablation and 1093 (87%) patients underwent RNU without a history of endoscopic ablation. The 5-year DFS and CSS rates were 72% and 77% in those with a history of tumor ablation vs 69% and 73% in those without a history of ablation (P = 0.171 and P = 0.365, respectively). In multivariate Cox regression analysis, history of ablation therapy was not associated with disease recurrence or cancer-specific mortality (hazard ratio [HR]: 0.79, P = 0.185 and HR: 0.7, P = 0.078, respectively). Our collaborative international efforts suggest that in selected patients, endoscopic tumor ablation does not adversely affect the recurrence and survival after subsequent RNU for UTUC. Our data support the continued role of ureteroscopic ablation of UTUC in appropriately selected patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90497/1/end-2E2010-2E0396.pd
Comparison of patients receiving salicylate before coronary artery surgery with patients not receiving in terms of postoperative mortality rates
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