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Research in economic geography has focused on the shift away from the standard employment relationship in the West; yet within these debates, non‐standard work is an amorphous stand‐in for many kinds of labour. Our aim is to account for absences and ambiguities within one form of non‐standard work – freelancing – to make the contours of this work more visible and to understand why a growing sector of the labour market is not well measured, protected or understood. Working from a Canadian case study, we first examine the conflicting ways freelancing is statistically measured, using an umbrella of intersecting terms that refer to labour or workers. Second, we critically review how freelancing is (not) legislated, organised and protected, areas of mediation which often still presume a standard employment relationship. Finally, we consider how the identity of 'freelancer' is lived, through freelancers' complex yet partial definitions that embrace flexibility and constraint. [ABSTRACT FROM AUTHOR]

Introduction: Cardiac arrest with cardioplegia is the most common and reliable method of myocardial protection in cardiac surgery, but there is no definite consensus on the use of different types of cardioplegia. Two of the commonly used types of cardioplegia are Bretschneider histidine-tryptophan-ketoglutarate solution (Custodiol) and conventional blood cardioplegia. In this study, Custodiol solution and conventional blood cardioplegia used in patients with type A aortic dissection who underwent supracoronary ascending aortic replacement were aimed to be compared in terms of postoperative results., Methods: 70 patients with type A aortic dissection who underwent supracoronary ascending aortic replacement in our clinic between January 2011 - October 2020 were included. Patients were divided into two groups, blood cardioplegia group ( n = 48) and Custodiol group ( n = 22) and they were compared regarding preoperative, perioperative and postoperative variables., Results: There was no significant difference between cardiopulmonary bypass time and cross-clamp time ( p = 0.17 and p = 0.16, respectively). Mechanical ventilator weaning time, intensive care unit stay and hospital stay were shorter in Custodiol group ( p = 0.04, p = 0.03 and p = 0.05, respectively). While inotropic support need was higher in the blood cardioplegia group ( p = 0.001), there was no significant difference in terms of mortality, arrhythmia, neurological complications and renal complications., Conclusions: Our results show that Custodiol cardioplegia solution may be superior to blood cardioplegia in reducing mechanical ventilation weaning period, intensive care and hospital stay, and reducing the use of inotropic agents in patients with type A aortic dissection undergoing supracoronary ascending aorta replacement., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objectives: In addition to the hemostatic properties of hemostatic agents, the investigation of their immunogenic properties, their local effects on application area has been the subject of many experimental studies. There are limited data on the inflammatory effects of Bovine serum albumin-glutaraldehyde and Polyethylene glycol polymer. Therefore, we investigated the effects of these agents on tissue reactions and inflammation in rabbit carotid artery anastomosis in our experimental study., Methods: Twenty-one New Zealand male rabbits were randomly divided into three groups. The right carotid artery anastomosis was performed on the control group after transection. Hemostatic agents were applied locally to other two groups separately after transection and anastomosis. At the end of 28 days, the type of inflammation, inflammatory cell infiltration, degree of inflammation, and amount of residual adhesives were examined and compared statistically., Results: Cell infiltrations associated with inflammation on the anastomosis site (eosinophils, epithelioid/giant cells, lymphocytes, and plasma cells) and inflammation grade in the groups of hemostatic agents were significantly lower compared to the control group ( p < .05). There was no difference between the hemostatic agents. While mild inflammation (61.9%) was dominant in the groups of hemostatic agents, moderate inflammation (85.7%) was more common in the control group. No severe inflammation was observed in any of the three groups. Residual sealant grade between hemostatic agents did not differ significantly., Conclusions: When inflammation and tissue reactions of the 4th week were evaluated, it was determined that both hemostatic agents did not cause severe inflammation. However, comparative results at multiple time intervals are needed due to the dynamic process of inflammation.

It is well-known that wireless communication technologies facilitate human life. However, the harmful effects of electromagnetic field (EMF) radiation on the human body should not be ignored. In the present study, we evaluated the effects of long-term, prenatal exposure to EMF radiation on the myocardium of rats at varying durations. Overall, 18 pregnant Sprague-Dawley rats were assigned into six groups ( n = 3 in each group). In all groups other than the control group, three pregnant rats were exposed to EMF radiation (900, 1800 and 2100 MHz) for 6, 12 and 24 h over 20 days. After delivery, the newborn male pups were identified and six newborn male pups from each group were randomly selected . Then, histopathological and biochemical analysis of myocardial samples were performed. When 24-h/day prenatal exposures to 900, 1800, 2100 MHz EMF radiation were evaluated, myocardial damage was greater in the 2100 MHz EMF-24h group than the other groups. In addition, when malondialdehyde (MDA) and glutathione (GSH) levels associated with reactive oxidative species (ROS) were evaluated, the MDA level was higher in the 2100 MHz EMF-24h group compared with the other groups. The GSH level was also lower in the 2100 MHz EMF-24h group. When the 6, 12 and 24 h/day prenatal exposures to 1800 MHz EMF radiation were evaluated, myocardial damage was greater in 1800 MHz EMF-24h group than the remaining groups ( p < 0.0001). Also, MDA level was greater in the 1800 MHz EMF-24h group compared with the other groups while the GSH level was lower in this group. It was shown that myocardial tissue was affected more by long-term exposure to EMF radiation at high frequencies. The data raise concerns that the harmful effects of non-ionizing radiation exposure on cardiac tissue will increase with 5G technology.

Background: The aim of this study is to investigate the effect of preoperative carotid body tumor embolization (CBTE) on the amount of bleeding, and vascular and neurological complications in carotid body tumors., Methods: Fifty patients treated for 51 carotid body tumors in 2 clinics, between 2005 and 2020, were evaluated. Polyvinyl alcohol embolization of the carotid body tumor was performed in 23 patients before the surgical excision. The results were compared with the remaining 28 patients, in whom CBTE was not performed, in terms of neurological complications, requirement of additional vascular interventions, bleeding amount, and length of hospital stay., Results: Mean bleeding amount was significantly lower in the CBTE group (406-217 mL, P < 0.05). Median erythrocyte suspension transfusion was significantly lower in the CBTE group (0.3 units vs. 1.1 units, P < 0.05). Neurological deficits developed in a total of 13 patients: 6 in the CBTE group and 7 in the non-CBTE group, in the early postoperative period (P = 0.90). No significant difference was observed between the groups in terms of additional vascular interventions and length of hospital stay (P = 0.79 and P = 0.61)., Conclusions: Carotid body tumors are rarely encountered tumors. However, their surgical excision is challenging for surgeons regarding intraoperative and postoperative bleeding. This study demonstrates that preoperative CBTE significantly reduces the amount of bleeding, especially in Shamblin type II/III tumors., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The most widely used commodity polymers in the rigid packaging industry are polypropylene (PP) and high-density polyethylene (HDPE). For example, blow molding grade of HDPE as a bottle and injection molding grade of PP as a cap are often used to produce detergent bottles. Therefore, the recycled HDPE bottles from post-consumer waste include PP as a contaminant originated from PP bottle caps. To simulate mechanical recycling of bottle waste, the mechanical properties of HDPE-rich-HDPE/PP virgin model blend were studied. For compatibilization, ethylene-based olefin block copolymer, propylene-based olefin block copolymer, ethylene propylene random copolymer, and styrene-butadiene-styrene triblock copolymer were chosen as potential compatibilizer candidates. Contact angle measurements, morphological analysis, adhesion tests of compatibilizer candidates to polymer blend components and the tensile as well as tensile impact properties of the ternary blends were studied. It was found that the ethylene-based olefin block copolymer was the most effective compatibilizer resulting in a return of mechanical properties to those of neat vHDPE due to its ability to encapsulate dispersed vPP particles in a vHDPE matrix (core-shell morphology) and the best adhesion to polymer blend components.

Plastic recycling strikes a balance between functional, mass producible products and environmental sustainability and is pegged by governments for rapid expansion. However, ambitious targets on recycled material adoption across new markets are at odds with the often heterogenous properties of contaminated regranulates. This study investigated polypropylene (PP) contamination in post-consumer low-density polyethylene (PE-LD) and mixed polyolefin (PO) regranulates. Calibration curves were constructed and PP content, its effect on mechanical properties and property recovery in compatibilised material assessed. FT-IR band ratios provided more reliable estimations of PP content than DSC melt enthalpy, which suffered considerable error for PP copolymers. PE-LD regranulates contained up to 7 wt.% PP contamination and were considerably more brittle than virgin PE-LD. Most mixed PO regranulates contained 45-95 wt.% PP and grew more brittle with increasing PP content. Compatibilisation with 5 wt.% ethylene-based olefin block copolymer resulted in PE-LD blends resembling virgin PE-LD and considerable improvements in the properties of mixed PO blends. These results illustrate the prevalence of PP in recycled PE, challenges associated with its quantification, effect on mechanical properties, and compatibilisation viability, thereby representing an important step towards higher quality regranulates to meet the recycling demands of tomorrow.

Objective: Since the systemic drugs have been used to reduce the hyperplasic response in the tunica intima, the periadventitial local drug applications to the vascular wall have gained more popularity. In this study, we investigated the effect of bovine serum albumin-glutaraldehyde and polyethylene glycol polymer on neointimal hyperplasia in rabbit carotid artery anastomosis to explore the effects of these two different agents., Methods: 21 New Zealand male rabbits were randomly divided into three groups. The carotid artery transection and anastomosis was performed onthe control group. The bovine serum albumin-glutaraldehyde and the polyethylene glycol polymer were applied locally on the other two groups seperatley after transection and anastomosis of the carotid arteries. At the end of 28-day follow-up, the histological and the immunohistochemical results related to neointimal hyperplasia were compared., Results: The glue residues were detected in the BSA-glutaraldehyde group, but in the PEG polymer group there was no glue residue. The intima thickness and the intima/media thickness ratio in the control group was significantly higher (p<0.05) than the other groups. These values did not differ significantly between the BSA-glutaraldehyde group and the PEG polymer group (p>0.05). The lumen diameter and the area in the control group were significantly higher (p < 0.05) than the BSA-glutaraldehyde group. These values between the control group and the PEG polymer group did not differ significantly (p>0.05). aSMA-positive staining score in the Control group was found to be significantly lower (p < 0.05) than the BSA-glutaraldehyde and PEG polymer group and the VEGF-positive staining score in the control group was found to be significantly higher (p < 0.05) than the BSA-glutaraldehyde and the PEG polymer group., Conclusions: Although the both agents have positive results on neointimal hyperplasia, it would be favorable to use polyethylene glycol polymer, since it does not seem to affect the lumen area and the lumen diameter of the vessel.

Polypropylene (PP) and Polyethylene (PE) are widely used commodity plastics in packaging industry such as detergent bottles. To produce plastic detergent bottles, very often extrusion blown molded PE-HD as a body and injection molded PP as a screw cap are used. Separation of individual polymer type is difficult due to the similar density. Unfortunately, the melt blending of recycled post-consumer detergent bottle waste leads to deterioration of mechanical properties. Additionally, the percentage of rPP contamination in recycled PE-HD (rPE-HD) from post-consumer bottle waste can be varied depending on local waste composition and different sorting quality. This work investigates the effect of various contamination scenarios with different percentage of rPP from bottle caps in rPE-HD from bottle waste as well as their compatibilization with olefin block copolymer (OBC) on mechanical, thermal, and rheological properties. Moreover, the low temperature tensile properties of blends with OBC are also investigated in this study. The results showed that the increasing rPP contamination leads to deteriorating elongation at break and tensile impact strength. Furthermore, the addition of OBC as a compatibilizer into worse-case contamination scenario (15 wt% rPP in rPE-HD) significantly improved elongation at break and tensile impact strength. Scanning electron microscopy (SEM) confirms the improvement in adhesion between rPP and rPE-HD from recycled bottle waste with the addition of OBC as a compatibilizer. Rheological measurements reveal the interfacial interaction among rPP, rPE-HD and OBC. The low temperature tensile test demonstrated that the addition of OBC as a compatibilizer improved low temperature tensile elongation at break., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Left sinus of Valsalva aneurysm (SVA) is a very infrequent clinical entity. Valsalva aneurysms are often asymptomatic in right and non-coronary sinuses and the diagnosis is often incidental. A left SVA which presents with exertional chest pain due to compression of left coronary system arteries is extremely rare. In this case, we present a successful surgical repair of left SVA without aortic regurgitation or myocardial infarction in a 59-year-old male patient.

Objective: Treatment of acute diseases of the aorta is still associated with high mortality and morbidity. It is believed that interventions for these diseases on overtime hours (night shifts or weekend shifts) may increase mortality. In this study, we investigated the effect of performing acute type A aortic dissection surgery on overtime hours in terms of postoperative outcomes., Methods: 206 patients who underwent emergency surgery for acute type A aortic dissection were retrospectively evaluated. Two groups were constituted: patients operated on daytime working hours (n=61), and patients operated on overtime hours (n=145), respectively., Results: Chronic obstructive pulmonary disease and repeat surgery were higher in group 1. There was no statistically significant difference between the two groups in terms of operative and postoperative results. Mortality rates and postoperative neurological complications in group 1 were 9.8% and 13.1%, respectively. In group 2, these rates were 13.8% and 12.4%, respectively (P=0.485 - P=0.890). Multivariate analysis identified that cross-clamp time, amount of postoperative drainage, preoperative loss of consciousness and postoperative neurological complications are the independent predictors of mortality., Conclusions: As the surgical experience of the clinics improves, treatment of acute type A aortic dissections can be successfully performed both overtime and daytime working hours.

Background: Apoptosis is thought to be induced by chemotherapy in cancer patients. Therefore, the measurement of its amplitude may be a useful tool to predict the effectiveness of cancer treatment sooner than conventional methods do., Patients and Methods: In the study presented, apoptosis was assessed with an ELISA-based assay in which caspase-cleaved cytokeratin 18 (M30-antigen), a novel specific biomarker of apoptosis, is measured. Thirty seven patients with malignant (nonmetastatic and metastatic) breast cancer, 35 patients with benign breast disease, and 34 healthy subjects were studied. Cancer patients received neoadjuvant chemotherapy consisting of either fluorouracil, epirubicin, and cyclophosphamide (FEC) or epirubicin plus docetaxel (ED). Apoptosis was detected before chemotherapy, 24 and 48 h after chemotherapy in the malignant group., Results: It was found that the baseline apoptosis level in either malignant but nonmetastatic group or benign group was not statistically different from that in the control group (p>0.05). However, it was statistically significantly higher in the metastatic group than that in the control group (p<0.05). Following the drug application, M30-antigen levels significantly increased at 24 h (p<0.05). The baseline M30-antigen levels increased about 3-times in patients showing tumor regression., Conclusions: M30-antigen level is increased after chemotherapy and its measurement may help clinicians to predict the effectiveness of chemotherapy sooner in breast cancer cases although confirmative larger trials are needed.