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51.
Jafar Chalabii Majid Movahedi Rad Ebrahim Hadizadeh Raisi Reza Esfandiari Mehni 《Materials》2022,15(21)
Although a sleeper makes a great contribution to the lateral resistance of ballasted tracks, in this regard, limited studies have been carried out on the effect of its contact surface with ballast aggregates. The current paper is dedicated to evaluating the effect of sleeper shape on the lateral resistance of ballasted track through discrete element modelling (DEM). For this purpose, firstly, a DEM model was validated based on the experimental results. Then, a sensitivity analysis was undertaken on the effect of the different contact areas that a standard concrete sleeper faces with the crib, shoulder and underlying ballast aggregates on lateral resistance of a single sleeper. As the main result of the current study, a high accurate regression equation for constant weight 319.2 kg and constant density 2500 kg/m3 of the sleepers was fitted between different sleeper contact areas and the maximum lateral resistance of a concrete sleeper for 3.5 mm lateral displacement in ballasted railway tracks. The obtained results showed that the effect of the sleeper’s head area compared to the underlying area of the sleeper and the head area of the sleeper compared to the sleeper’s side area in terms of lateral resistance are 8.2 times and 14.5 times more, respectively. 相似文献
52.
Fretting corrosion at the head–neck interface of modular hip implants, scientifically termed trunnionosis/taperosis, may cause regional inflammation, metallosis, and adverse local tissue reactions. The severity of such a deleterious process depends on various design parameters. In this review, the influence of surface topography (in some cases, called microgrooves/ridges) on the overall performance of the microgrooved head–neck junctions is investigated. The methodologies together with the assumptions and simplifications, as well as the findings from both the experimental observations (retrieval and in vitro) and the numerical approaches used in previous studies, are presented and discussed. The performance of the microgrooved junctions is compared to those with a smooth surface finish in two main categories: stability and integrity; wear, corrosion, and material loss. Existing contradictions and disagreements among the reported results are reported and discussed in order to present a comprehensive picture of the microgrooved junctions. The current research needs and possible future research directions on the microgrooved junctions are also identified and presented. 相似文献
53.
Jean-Baptiste Bouillon-Minois Justin Outrey Bruno Pereira Oluwaseun John Adeyemi Vincent Sapin Damien Bouvier David Thivel Sarah de Saint-Vincent Ukadike Chris Ugbolue Julien S. Baker Reza Bagheri Jeannot Schmidt Marion Trousselard Frdric Dutheil 《Nutrients》2022,14(23)
Despite the available literature on the consequences of night shiftwork on stress and food intake, its impact on leptin and ghrelin has never been studied. We previously demonstrated that leptin and ghrelin were biomarkers related to stress, and acute stress-induced a decrease in leptin levels and an increase in ghrelin levels. We performed a prospective observational study to assess the influence of night work, nutrition, and stress on the levels of ghrelin and leptin among emergency healthcare workers (HCWs). We took salivary samples at the beginning of a day shift and/or at the end of a night shift. We also monitored stress using the job demand-control-support model of Karasek. We recorded 24-h food intake during the day shift and the consecutive night shift and during night work and the day before. We included 161 emergency HCWs. Emergency HCWs had a tendency for decreased levels of leptin following the night shift compared to before the dayshift (p = 0.067). Furthermore, the main factors explaining the decrease in leptin levels were an increase in job-demand (coefficient −54.1, 95 CI −99.0 to −0.92) and a decrease in job control (−24.9, −49.5 to −0.29). Despite no significant changes in ghrelin levels between shifts, social support was the main factor explaining the increase in ghrelin (6.12, 0.74 to 11.5). Food intake (kcal) also had a negative impact on leptin levels, in addition to age. Ghrelin levels also decreased with body mass index, while age had the opposite effect. In conclusion, we confirmed that ghrelin and leptin as biomarkers of stress were directly linked to the job demand-control-support model of Karasek, when the main cofounders were considered. 相似文献
54.
55.
Reza Yadollahvandmiandoab Mehrsa Jalalizadeh Keini Buosi Herney Andrs Garcia-Perdomo Leonardo Oliveira Reis 《Current oncology (Toronto, Ont.)》2022,29(9):6700
Purpose: Bladder cancer is the 13th most common cause of cancer death with the highest lifetime cost for treatment of all cancers. This scoping review clarifies the available evidence on the role of a novel therapeutic approach called immunogenic cell death (ICD) in urothelial cancer of the bladder. Methods: In accordance with the recommendations of the Joanna Briggs Institute, we searched MEDLINE (Ovid), EMBASE, CENTRAL databases, and supplemented with manual searches through the conferences, Google scholar, and clinicaltrials.gov for published studies up to April 2022. We included literature that studied molecular mechanisms of ICD and the role of certain danger-associated molecular patterns (DAMPs) in generating ICD, safety and efficacy of different ICD inducers, and their contributions in combination with other urothelial cancer treatments. Results: Oncolytic viruses, radiotherapy, certain chemo/chemo radiation therapy combinations, photodynamic therapy, and novel agents were studied as ICD-inducing treatment modalities in the included studies. ICD was observed in vitro (murine or human urothelial carcinoma) in ten studies, eight studies were performed on mouse models (orthotopic or subcutaneous), and five clinical trials assessed patient response to ICD inducing agents. The most common studied DAMPs were Calreticulin, HMGB1, ATP, and Heat Shock Proteins (HSP) 70 and 90, which were either expressed on the cancer cells or released. Conclusion: ICD inducers were able to generate lasting antitumor immune responses with memory formation in animal studies (vaccination effect). In clinical trials these agents generally had low side effects, except for one trial, and could be used alone or in combination with other cancer treatment strategies in urothelial cancer patients. 相似文献
56.
Mohammad Ali Zolfigol Saeed Baghery Ahmad Reza Moosavi-Zare Seyed Mohammad Vahdat Heshmatollah Alinezhad Mohammad Norouzi 《RSC advances》2022,12(42):27212
Retraction of ‘Design of 1-methylimidazolium tricyanomethanide as the first nanostructured molten salt and its catalytic application in the condensation reaction of various aromatic aldehydes, amides and β-naphthol compared with tin dioxide nanoparticles’ by Mohammad Ali Zolfigol et al., RSC Adv., 2015, 5, 45027–45037, https://doi.org/10.1039/C5RA02718G.The Royal Society of Chemistry hereby wholly retracts this RSC Advances article as the synthesis of 1-methylimidazolium tricyanomethanide reported in the article, whereby tricyanomethane is used as a starting material, is not reproducible. The authors stated that they did not report the synthesis of tricyanomethane in the published paper as they purchased this compound from a commercial center and used it in the synthesis of ionic liquids, molten salts and various kinds of catalysts. The authors thought the reaction between tricyanomethane and organic bases is a simple acid–base reaction, therefore they did not cite the previously reported literature and its related history for the preparation of tricyanomethane. However, according to papers by Banert et al.,1,2 and based on their obtained analysis of the chemical sold to them as tricyanomethane, it became clear to the authors that this purchased compound was not tricyanomethane as there were differences in the 1H NMR and 13C NMR chemical shift between the purchased compound and the reports of Banert et al.1 According to these documents, the authors believe that the compound sold to them as tricyanomethane was fake. While the authors have now re-prepared 1-methylimadazolium tricyanomethanide, by synthesising potassium tricyanomethanide as a starting material for the synthesis,3–5 the synthesis reported in this article is not accurate. Therefore, this article is being retracted to avoid misleading readers and to protect the accuracy and integrity of the scientific record.Mohammad Ali Zolfigol, Saeed Baghery and Ahmad Reza Moosavi-Zare oppose the retraction. Seyed Mohammad Vahdat, Heshmatollah Alinezhad and Mohammad Norouzi were contacted but did not respond.Signed: Laura Fisher, Executive Editor, RSC AdvancesDate: 17th August 2022 相似文献
57.
Maral Salek-Maghsoodi Zahra Golsanamlu Sanam Sadeghi-Mohammadi Masoud Gazizadeh Jafar Soleymani Reza Safaralizadeh 《RSC advances》2022,12(49):31535
This article describes the design, synthesis and characterization of a sensor suitable for practical measurement of ionized calcium in water samples and cancer cells. Calcium is an important ion in living organs and works as a messenger in several cellular functions. A lack of Ca ions interrupts the immune system and can lead to several diseases. A novel magnetic-polydopamine nanoparticle (PDNP)/rhodamine B (RhB)/folic acid (FA) nanoparticle was developed for the determination of calcium ions in MCF 7 cell lysates and water samples. Furthermore, the produced nanoparticle was employed for bioimaging of folate receptor (FR)-overexpressed cancer cells. This nanoprobe displayed a bright photoluminescence emission at 576 nm under an excitation wavelength of 420 nm. In the presence of calcium ions, the fluorescence emission of the MNPs-PDNPs/RhB/FA probe was proportionally decreased from 20 ng mL−1 to 100 ng mL−1 and 0.5 μg mL−1 to 20 μg mL−1 with a lower limit of quantification (LLOQ) of about 20 ng mL−1. The developed sensor showed a low-interference manner in the presence of possible coexistence interfering ions. In addition, this nanomaterial showed excellent biocompatibility with favorable differentiation ability to attach to the FR-positive cancer cells. The MNPs-PDNPs/RhB/FA nanoparticle has been utilized for bioimaging of the MCF 7 cell with favorable differentiation ability.Synthesis of the MNPs-PDNPs/RhB/FA probe and application for bioimaging and Ca detection. 相似文献
58.
Mohsen Chiani Kayhan Azadmanesh Mohammad Ali Shokrgozar Mohammad Reza Mehrabi Azim Akbarzadeh Dariush Norouzian 《Chemical biology & drug design》2017,90(5):953-961
Folate receptor (FR)‐mediated drug delivery is a promising approach for active targeting of drugs to the FR‐positive tumor cells. Bleomycin (BLM) is an antitumor antibiotic with poor therapeutic activity as a result of its limited diffusion into tumor cells. The aim of this study was to investigate whether FR‐targeted PEGylated nanoliposomes (FPNL) can effectively deliver BLM to tumor cells and enhance its in vitro and in vivo efficacy. FPNL and PNL (non‐targeted) were prepared by thin film hydration method, and their physiochemical properties, cellular uptake, tissue distribution and tumor inhibitory effects were investigated. In Lewis lung cancer (LLC1) cells, FPNL containing BLM showed 2.38‐fold and 3.26‐fold higher cytotoxicity compared to PNL‐BLM and free BLM, respectively. Moreover, the uptake of FPNL by these cells was increased as compared to the PNL. Furthermore, FPNL showed significantly higher tumor distribution of BLM in the LLC1 cells and more tumor inhibition efficacy compared to free BLM and PNL. Both formulations of nanoliposomes had longer plasma half‐life than that of free BLM. Therefore, FPNL may be suitable carriers for targeted drug delivery to FR‐positive tumor cells. 相似文献
59.
Alireza Rezvani Reza Shahriarirad Amirhossein Erfani Keivan Ranjbar 《Clinical Case Reports》2022,10(8)
Epithelioid hemangioendothelioma is considered an uncommon tumor originating from vascular tissues. Although this disease is an extremely rare malignant cancer, its pleural subtype is even less common. We discuss a 68‐year‐old man with isolated pleural epithelioid hemangioendothelioma, along with a literature review of all similar cases. 相似文献
60.
自体结膜角巩膜缘移植治疗原发性翼状胬肉 总被引:1,自引:1,他引:0
Mahmoud Jabbbarvand Mohammad Reza Khalili Mohammad Taher najabi 《国际眼科杂志》2008,8(3):456-459
目的:评价自体结膜角巩膜缘移植术治疗原发性翼状胬肉的有效性。方法:原发性翼状胬肉患者15例(15眼),接受自体结膜角巩膜缘移植术。切除翼状胬肉后,植片的角膜缘部分与翼状胬肉切除处的角膜缘对位缝合,植片的上皮面向上。纤维血管组织在原翼状胬肉区遮盖角膜1mm以上定为复发。结果:随访平均8mo,所有的患者既无一例复发也无并发症发生。结论:单纯翼状胬肉切除联合自体结膜角巩膜缘移植是一种治疗原发性翼状胬肉安全有效的手术方法。 相似文献