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91.
Jamal Kazmi Poh Choon Ooi Boon Tong Goh Min Kai Lee M. F. Mohd. Razip Wee Siti Shafura A Karim Syed Raza Ali Raza Mohd Ambri Mohamed 《RSC advances》2020,10(39):23297
Room-temperature ferromagnetism in the large and direct bandgap diluted magnetic semiconductor zinc oxide (ZnO) is attributed to the intrinsic defects and p-orbital–p-orbital (p–p) coupling interaction. However, due to oxidation, the ferromagnetism induced by defects is unstable. In the present work, the solution process synthesis route was utilized to grow pristine and bismuth-doped, highly crystalline ZnO nanowire (ZnO NW)-based samples. The FE-SEM images showed that the grown ZnO NWs have a preferred orientation along the c-axis in the (001) direction due to the anisotropic crystal nature of ZnO. X-ray photoelectron spectroscopy (XPS) confirmed the presence of Bi, and at a higher doping content, the bismuth oxide phase appeared. The XRD patterns showed the wurtzite crystal structure, and the large intensity of the (002) peak suggests that most of the reflection was from the top hexagonal face of the NWs, and thus, the wires are predominantly aligned along the c-axis. The TEM analysis further confirmed the crystal growth direction along the (001) direction. The UV-Visible absorption and PL measurements also showed a decrease in the bandgap with an increase in doping concentration, which may be associated with the sp–d exchange interaction between the localized d-electrons and band electrons of the Bi ions. Bi-doping tended to increase the PL intensity in the visible region. The magnetic properties measured by SQUID at 4 and 300 K showed ferromagnetic behaviour for both the pristine and Bi-doped samples. However, the saturation magnetization for the Bi-doped samples was higher compared to that of the pristine ZnO samples until the threshold doping value. The obtained results demonstrated that Bi-doping can be used to tune both the optical and magnetic properties of ZnO NWs, hence paving the way for future spintronics and spin-polarized optoelectronics applications.Room-temperature ferromagnetism in the large and direct bandgap diluted magnetic semiconductor zinc oxide (ZnO) is attributed to the intrinsic defects and p-orbital–p-orbital (p–p) coupling interaction. 相似文献
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Objective
Blunt abdominal trauma is a diagnostic challenge for emergency physicians and ultrasonography is one of the diagnostic tools used in this type of injuries. The aim of this study was to evaluate the diagnostic value of ultrasonographies performed by emergency physicians and radiologists.Methods
This prospective diagnostic study was performed in the emergency departments of two trauma centers in Iran during a period of 12 months. The subjects were all patients with blunt abdominal trauma that were candidated for abdominopelvic computed tomography (CT) scanning in our emergency departments. The results of focused assessment with sonography for trauma (FAST) performed by emergency physicians and radiologists were compared blindly with the results of CT scans performed by radiologists. The sensitivity, specificity, and predictive values of diagnosis for different abdominal anatomic areas were calculated.Results
In total, 450 patients undergoing FAST and CT scanning were studied. The sensitivity of radiologists’ diagnoses for Morison’s, splenorenal, perivesical, and pleural effusion areas were, respectively, 88.0, 70.0, 38.0, and 30.0 %. The corresponding values for emergency physicians’ diagnoses were, respectively, 82.0, 60.0, 28.0, and 30.0 %. The specificity of radiologists’ diagnoses in the mentioned areas were, respectively, 98.9, 100, 93.1, and 100 %, and for emergency physicians, they were, respectively, 98.9, 100, 96.0, and 100 %.Conclusion
Emergency physicians showed a promising performance in applying FAST in blunt abdominal trauma. The specificity of ultrasonographic diagnosis in the emergency physicians group and the radiologists group were comparable, while radiologists showed a higher performance regarding the sensitivity of the ultrasonographic diagnosis. 相似文献94.
95.
Correction for ‘Electrochemical behaviour and analysis of Zn and Zn–Ni alloy anti-corrosive coatings deposited from citrate baths’ by Shams Anwar et al., RSC Adv., 2018, 8, 28861–28873, DOI: 10.1039/C8RA04650F.The authors regret a mistake in the author names of ref. 44. The correct reference is shown below as ref. 1.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
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Efficacy of Crocus sativus L. on reduction of cadmium‐induced toxicity on spermatogenesis in adult rats
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A. Yari A. Sarveazad E. Asadi J. Raouf Sarshoori A. Babahajian N. Amini F. Amidi H. Bahadoran MT. Joghataei MH. Asadi A. Shams 《Andrologia》2016,48(10):1244-1252
Cadmium is a toxic heavy metal element, which probably cause infertility by impairment in spermatogenesis. The present work aimed (i) to study the toxic effect of cadmium on spermatogenesis in rat, as well as (ii) the protective effect of Crocus sativus L. on cadmium‐intoxicated rats. Cadmium chloride was administered intraperitoneally during 16 days at intervals of 48 h between subsequent treatments. Crocus sativus L. was pre‐treated in both of control and cadmium‐injected rats. Animals were sacrificed on day 17 after the first treatment. The left cauda epididymis was removed and immediately immersed into Hank's balanced salt solution for the evaluation of sperm count and viability, and left testis was fixed in 10% formalin for histological evaluation. Following contamination with cadmium, a decrease was observed in the number and viability of cauda epididymis sperm, which were increased by Crocus sativus L. pre‐treatment (P < 0.05). In addition, cadmium decreased both cell proliferation and Johnsen Scores in the seminiferous tubules, which were reversed by Crocus sativus pre‐treatment (P < 0.05). Furthermore, cadmium‐induced decrease in the amount of free serum testosterone as well as an increase in lipid peroxidation activity in the testicular tissue was reversed by Crocus sativus L. (P < 0.05). These findings may support the concept that Crocus sativus L. can improve the cadmium toxicity on spermatogenesis. 相似文献
99.
Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph. 相似文献
100.
Ahmed Shams Mohamed El-Sayed Osama Gamal Waled Ewes 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2016,26(8):837-842