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Background
The “gig” economy connects consumers with contractors (or workers) through online platform businesses to perform tasks (or “gigs”). This innovation in technology provides businesses and consumers access to low-cost, on-demand labour, but gig workers’ experiences are more complex. They have access to very flexible, potentially autonomous work, but also deal with challenges caused by the nature of the work, its precariousness, and their relationships with the platform businesses. Workers in the Global North and South may also experience these challenges very differently. Based on our report “Towards an Understanding of Canadian Workers in the Global Gig Economy”, we present a commentary on the implications of a globalized online platform labour market on the health of gig workers in Canada and globally.Main body
Based on our scoping review of peer and grey literature, we categorized gig worker vulnerabilities in three ways: 1) occupational vulnerabilities, 2) precarity, and 3) platform-based vulnerabilities. Occupational vulnerabilities are connected to the work being performed (e.g. driving a car or computer work) and are not specific to platform labour. Precarity refers to the short-term, contingent nature of the work, characteristics that may be shared with other forms of work. Some examples of precariousness are lack of health insurance, collective bargaining, or career training and promotion. Finally, platform-based vulnerabilities are particular to the way platform labour is structured. These vulnerabilities include worker misclassification, information asymmetries, and the culture of surveillance. We suggest that, together, these vulnerabilities challenge gig workers’ right to health.Conclusions
We propose that the experience of gig workers around the world must be understood in the context of neoliberalism, which has increased both the globalization and precaritization of work. While gig workers share some vulnerabilities, which have important negative consequences on their health, with other workers, the platform-specific vulnerabilities of workers require further inquiry. In particular, the specific health and overall experience of gig workers in different regions of the world – with different labour policies and sociopolitical contexts for work – must be disentangled as workers in the Global North and South experience this work very differently.3.
Hannah D. Peach Jane F. Gaultney Aria R. Ruggiero 《The journal of primary prevention》2018,39(6):555-570
Although a few studies have examined sleep knowledge and attitudes as predictors of sleep behavior, the question of which better predicts actual sleep behavior is still open. Furthermore, the construct of sleep attitudes has been inconsistently defined and measured. We examined both sleep knowledge and attitudes to determine their unique associations with sleep hygiene behaviors, and direct and indirect associations with objective and subjective sleep outcomes. College students (N?=?218) completed a series of questionnaires before and after wearing a FitBit Flex accelerometer for 7 days. We collected objective sleep duration and quality using this apparatus, while participants reported subjective sleep outcomes, hygiene behaviors, knowledge, and attitudes. Analyses controlled for self-reported depression, diagnosed sleep disorder, and sleep-related medications. For both objective and subjective measures, more positive sleep attitudes but not greater sleep knowledge was directly associated with longer sleep duration, and indirectly (through sleep hygiene) with better sleep quality. The role of sleep attitudes in sleep-related behaviors and outcomes deserves further investigation as a potentially modifiable factor in sleep intervention efforts. 相似文献
4.
This study analyzed the depth of cure of a composite assessed by microhardness and the degree of conversion as a function of the light cure unit (LCU) used. Two light cure units, one LED (Ultraled-Dabi Atlante) and one quartz-tungsten-halogen (QTH, Optilux 401-Demetron) unit were used to cure 4.0 x 4.0 mm and 5.0 mm deep composite specimens (Filtek Z250, 3M ESPE). After 24 hours storage at 37 degrees C, Knoop microhardness and degree of conversion were measured on the irradiated surface and at each millimeter of the sample's depth. The degree of conversion was determined by using micro-Raman spectroscopy. The specimens cured with the QTH unit presented uniform decay in microhardness up to 4 mm in depth. Beyond 4 mm, the drop was abrupt. With LED photoactivation, uniform decay was observed only up to 2 mm. At higher depths, the decay in microhardness increased rapidly, especially beyond 3 mm. Depth of cure assessed by micro-Raman revealed that the degree of conversion behaved similarly to microhardness for both LCUs. A strong linear regression between microhardness and the degree of conversion, including both LCUs, was established with R2 = 0.980. 相似文献
5.
Fiore Manganelli Raffaele Dubbioso Rosa Iodice Antonietta Topa Andrea Dardis Cinzia Valeria Russo Lucia Ruggiero Stefano Tozza Alessandro Filla Lucio Santoro 《Journal of neurology》2014,261(4):804-808
Adult patients with Niemann-Pick disease type C (NPC) usually develop cognitive impairment progressing to dementia, whose pathophysiology remains still unclear. Noteworthy parallels exist in cognitive impairment and cellular pathology of NPC and Alzheimer’s disease (AD). In particular, alterations of cholinergic system, which represent one of the pathological hallmarks and contribute to cognitive deterioration in AD, have recently been demonstrated in a human brain autopsy and in an experimental model of NPC. This finding raised the issue that central cholinergic circuits dysfunction may contribute to pathophysiology of cognitive impairment in NPC as well, and prompted us to evaluate the cholinergic functional involvement in NPC patients by applying a neurophysiologic technique, named short-latency afferent inhibition (SAI). We describe clinical, biochemical, molecular and neuropsychological features, and SAI findings in three patients affected by NPC. Diagnosis of NPC was assessed by molecular analysis of the NPC1 gene in all patients. In two of them, biochemical analysis of intracellular accumulation of unesterified cholesterol was also performed. The main clinical features were cerebellar ataxia, vertical supranuclear gaze palsy and a variable degree of cognitive impairment ranging from only memory impairment to severe dementia. Electrophysiological evaluation revealed a reduced SAI in all three patients. Our SAI findings provide evidence of cholinergic dysfunction in patients with the adult form of NPC, supporting that cholinergic alterations may play a role in cognitive impairment in NPC, and strengthening the similarities between NPC and AD. 相似文献
6.
Piero Ruggenenti Barbara Ruggiero Paolo Cravedi Marina Vivarelli Laura Massella Maddalena Marasà Antonietta Chianca Nadia Rubis Bogdan Ene-Iordache Michael Rudnicki Rosa Maria Pollastro Giovambattista Capasso Antonio Pisani Marco Pennesi Francesco Emma Giuseppe Remuzzi 《Journal of the American Society of Nephrology : JASN》2014,25(4):850-863
The outcome of steroid-dependent or frequently relapsing nephrotic syndrome of minimal change disease (MCD), mesangial proliferative GN (MesGN), or FSGS may be poor and with major treatment toxicity. This academic, multicenter, off-on trial (ClinicalTrials.gov #) primarily evaluated the effects of rituximab therapy followed by immunosuppression withdrawal on disease recurrence in 10 children and 20 adults with MCD/MesGN (n=22) or FSGS who had suffered ≥2 recurrences over the previous year and were in steroid-induced remission for ≥1 month. Participants received one dose (n=28) or two doses of rituximab (375 mg/m2 intravenously). At 1 year, all patients were in remission: 18 were treatment-free and 15 never relapsed. Compared with the year before rituximab treatment, total relapses decreased from 88 to 22 and the per-patient median number of relapses decreased from 2.5 (interquartile range [IQR], 2–4) to 0.5 (IQR, 0–1; P<0.001) during 1 year of follow-up. Reduction was significant across subgroups (children, adults, MCD/MesGN, and FSGS; P<0.01). After rituximab, the per-patient steroid maintenance median dose decreased from 0.27 mg/kg (IQR, 0.19–0.60) to 0 mg/kg (IQR, 0–0.23) (P<0.001), and the median cumulative dose to achieve relapse remission decreased from 19.5 mg/kg (IQR, 13.0–29.2) to 0.5 mg/kg (IQR, 0–9.4) (P<0.001). Furthermore, the mean estimated GFR increased from 111.3±25.7 to 121.8±29.2 ml/min per 1.73 m2 (P=0.01), with the largest increases in children and in FSGS subgroups. The mean height z score slope stabilized in children (P<0.01). Treatment was well tolerated. Rituximab effectively and safely prevented recurrences and reduced the need for immunosuppression in steroid-dependent or frequently relapsing nephrotic syndrome, and halted disease-associated growth deficit in children.Idiopathic nephrotic syndrome (NS) in children and young adults is almost invariably the clinical counterpart of a continuum of glomerular diseases ranging from the relatively frequent minimal change disease (MCD) and the less frequent mesangial proliferative GN (MesGN), which are predominantly observed in children, to the relatively uncommon FSGS that is observed more frequently in adult patients. NCT009818381 In a small minority of patients that are generally resistant to immunosuppressive therapies, the disease is due to molecular defects of one of the podocyte genes.2 In all of the other cases, it appears to be immune-mediated, but the pathophysiologic process underlying glomerular injury remains poorly understood.3Independent of the underlying renal pathology, prednisone continues to be the cornerstone treatment at disease onset, achieving remission within 4 weeks in approximately 90% of children with MCD and in 20%–60% of those with FSGS.4,5 However, 60%–70% of patients relapse after steroid tapering or withdrawal, and most require repeat courses of prednisone to achieve remission of recurrent episodes and/or the addition of other immunosuppressive medications, such as calcineurin inhibitors, mycophenolate mofetil, or alkylating agents, to reduce the number of relapses and prevent major side effects of steroid treatment.6 According to their relapse rate, these patients are classically labeled as “steroid-dependent” or “frequently relapsing”. In these patients, serious adverse effects of treatment associate with complications of relapsing episodes of heavy proteinuria. These are the patients in most urgent need of more effective and safer treatment.The possibility of a specific and, hopefully, safer approach to patients with steroid-dependent or frequently relapsing NS emerged in 2004 when the B cell–depleting mAb rituximab was reported to induce remission of proteinuria in a child with frequently relapsing NS secondary to MCD who had received this medication to cure a supervened idiopathic thrombocytopenic purpura.7 Subsequent uncontrolled observations found some effect of rituximab in patients with steroid-dependent or frequently relapsing MCD,8–11 suggesting that B-cell immunity could play a key role in the pathophysiology of the disease. Controlled studies in support of this hypothesis, however, have been both scanty and almost confined to children12,13 or to patients with MCD who were evaluated in the context of a retrospective, observational design.14 Indeed, less attention was given to adults and patients with FSGS given difficulties in designing adequately powered trials.Here, we designed a longitudinal, off-on study (ClinicalTrials.gov #) to evaluate the efficacy of rituximab in reducing the incidence of relapses and need for steroid and other immunosuppressive medications in children and adults with steroid-dependent or frequently relapsing NS due to MCD, MesGN, or FSGS. To minimize the side effects and costs of rituximab, we abandoned the standard four-dose protocol originally implemented for the treatment of B-cell lymphomas, NCT0098183815 and adopted a new B cell–driven regimen we found to achieve remission of NS in patients with idiopathic membranous nephropathy (IMN) as effectively as the standard protocol, but with fewer side effects and less costs.16 相似文献
7.
Tara M. Connelly Arthur S. Berg Leonard R. Harris III John P. Hegarty Francesca M. Ruggiero Susan M. Deiling David L. Brinton Walter A. Koltun 《The Journal of surgical research》2014
Background
The T-cell activation Rho GTPase–activating protein (TAGAP) gene has a regulatory role in T cell activation. We have previously suggested a correlation between the TAGAP-associated single nucleotide polymorphism rs212388 and protection from anal sepsis in Crohn's disease (CD) patients. The present study sought to evaluate TAGAP's expression in colonic tissue of CD patients with varying disease severity and location.Materials and methods
Five transverse, 17 left, and five sigmoid colectomy specimens from 27 CD patients with varying disease severity (16 male, mean age at diagnosis 26.4 ± 2.2 y) were evaluated for TAGAP messenger RNA expression. Fisher exact, Mann–Whitney, and Welch two-sample t-tests were used for statistical evaluation. Immunohistochemistry confirmed results.Results
Patients with tissue demonstrating lower TAGAP messenger RNA expression (less than the overall mean) were younger at diagnosis (mean age 21.1 ± 6.3 versus 32.5 ± 13 y, P = 0.009). Increased TAGAP expression was seen in moderate or severely diseased tissue versus tissue with no or mild disease (RQ = 1.3 ± 0.34 versus 0.53 ± 0.09, P = 0.050). This was the most dramatic in the sigmoid colon (P = 0.041). TAGAP expression was increased in more distal tissue with a significant difference seen when comparing transverse versus sigmoid colon with moderate or severe disease (0.51 ± 0.14 versus 1.9 ± 0.37, P = 0.049).Conclusions
Colonic expression of TAGAP in CD patients varied according to disease severity and location, being the most elevated in patients with severe disease in the sigmoid colon. Whether changes in TAGAP expression are a result of disease response or inherent to the disease pathophysiology itself remains to be determined. This gene warrants further investigation for its role in CD. 相似文献8.
Response to Comments on “Diagnosis and Management of Osteoporosis of the Jaw: A Systematic Review and International Consensus” 下载免费PDF全文
9.
This review focuses upon the development of a small animal model that incorporates exposure to chronic-intermittent hypoxia to produce systemic hypertension similar to that experienced by humans with the obstructive sleep apnea syndrome. It has been suggested that experimentally-induced hypertension, like human hypertension, is due to activation of the sympathetic nervous system. That hypothesis is supported by physiological studies carried out in humans with obstructive sleep apnea as well as in animals exposed to chronic-intermittent hypoxia. Furthermore, recent anatomical studies of exposed animals strongly suggested that activation was widespread and included cortical and brainstem components of the sympathetic system. Such findings, while illustrating the complexity of modeling human disease in animals, also demonstrate the heuristic value of chronic-intermittent hypoxia as an experimental approach. 相似文献
10.
Fabiana Fattori Lorenzo Maggi Claudio Bruno Denise Cassandrini Valentina Codemo Michela Catteruccia Giorgio Tasca Angela Berardinelli Francesca Magri Marika Pane Anna Rubegni Lucio Santoro Lucia Ruggiero Patrizio Fiorini Antonella Pini Tiziana Mongini Sonia Messina Giacomo Brisca Irene Colombo Guja Astrea Chiara Fiorillo Cinzia Bragato Isabella Moroni Elena Pegoraro Maria Rosaria D’Apice Enrico Alfei Marina Mora Lucia Morandi Alice Donati Anni Evilä Anna Vihola Bjarne Udd Pia Bernansconi Eugenio Mercuri Filippo Maria Santorelli Enrico Bertini Adele D’Amico 《Journal of neurology》2015,262(7):1728-1740
Centronuclear myopathies (CNMs) are a group of clinically and genetically heterogeneous muscle disorders. To date, mutation in 7 different genes has been reported to cause CNMs but 30 % of cases still remain genetically undefined. Genetic investigations are often expensive and time consuming. Clinical and morphological clues are needed to facilitate genetic tests and to choose the best approach for genetic screening. We aimed to describe genotype–phenotype correlation in an Italian cohort of patients affected by CNMs, to define the relative frequencies of its defined genetic forms and to draw a diagnostic algorithm to address genetic investigations. We recruited patients with CNMs from all the Italian tertiary neuromuscular centers following clinical and histological criteria. All selected patients were screened for the four ‘canonical’ genes related to CNMs: MTM1, DNM2, RYR1 and BIN1. Pathogenetic mutations were found in 38 of the 54 screened patients (70 %), mostly in patients with congenital onset (25 of 30 patients, 83 %): 15 in MTM1, 6 in DNM2, 3 in RYR1 and one in TTN. Among the 13 patients with a childhood–adolescence onset, mutations were found in 6 patients (46 %), all in DNM2. In the group of the 11 patients with adult onset, mutations were identified in 7 patients (63 %), again in DNM2, confirming that variants in this gene are relatively more common in late-onset phenotypes. The present study provides the relative molecular frequency of centronuclear myopathy and of its genetically defined forms in Italy and also proposes a diagnostic algorithm to be used in clinical practice to address genetic investigations. 相似文献