Visiting and Office Home Care Workers’ Occupational Health: An Analysis of Workplace Flexibility and Worker Insecurity Measures Associated with Emotional and Physical Health

The home health care sector in Canada experienced major restructuring in the mid-1990s creating a variety of flexibilities for organizations and insecurities for workers. This paper examines the emotional and physical health consequences of employer flexibilities and worker insecurities on home health care workers. For emotional health the focus is on stress and for physical health the focus is on selfreported musculoskeletal disorders. Data come from our survey of home health care workers in a mid-sized city in Ontario, Canada. Data are analyzed separately for 990 visiting and 300 office workers. For visiting workers, results showed that none of the ‘objective’ flexibility/insecurity measures are associated with stress or musculoskeletal disorders controlling for other factors. However, ‘subjective’ flexibility/insecurity factors, i.e. feelings of job insecurity and labour market insecurity, are significantly and positively associated with stress. When stress is included in the analysis, for visiting workers stress mediates the effects of ‘subjective’ flexibility/insecurity with musculoskeletal disorders. For office workers, none of the objective flexibility/insecurity factors are associated with stress but subjective flexibility/insecurity factor of feelings of job insecurity is positively and significantly associated with stress. For office home care workers, work on call is negatively and significantly associated with musculoskeletal disorders. Feeling job insecurity is mediated through stress in affecting musculoskeletal disorders. Feeling labour market insecurity is significantly and positively associated with musculoskeletal disorders for office home care workers. Decision-makers in home care field are recommended to pay attention to insecurities felt by workers to reduce occupational health problems of stress and musculoskeletal disorders.home health care workers, stress, worker insecurity

Microwave-controlled generation of shaped single photons in circuit quantum electrodynamics

Large-scale quantum information processors or quantum communication networks will require reliable exchange of information between spatially separated nodes. The links connecting these nodes can be established using traveling photons that need to be absorbed at the receiving node with high efficiency. This is achievable by shaping the temporal profile of the photons and absorbing them at the receiver by time reversing the emission process. Here, we demonstrate a scheme for creating shaped microwave photons using a superconducting transmon-type three-level system coupled to a transmission line resonator. In a second-order process induced by a modulated microwave drive, we controllably transfer a single excitation from the third level of the transmon to the resonator and shape the emitted photon. We reconstruct the density matrices of the created single-photon states and show that the photons are antibunched. We also create multipeaked photons with a controlled amplitude and phase. In contrast to similar existing schemes, the one we present here is based solely on microwave drives, enabling operation with fixed frequency transmons

Cuantificación del calcio mineral en la ateromatosis carotídea mediante angiografía por tomografía computarizada: perfil evolutivo y relación con la progresión del grado de estenosis volumétrica

Antecedentes: La cuantificación y caracterización del calcio (Ca) mineral (hidroxiapatita) en la bifurcación carotídea con AngioTC, y su relación con la sintomatología neurológica, en un estudio preliminar de casos y controles (Miralles y cols. Eur J Vasc Endovasc Surg 2006), constituye la base conceptual del presente estudio. Sus resultados, al igual que los de otras publicaciones, sugerían un posible papel protector del calcio en el desarrollo de eventos neurológicos. Sin embargo, su relación con la progresión de la ateromatosis carotídea ha sido escasamente analizado. Objetivos: Principales: 1. Diseñar un método de medición volumétrica de la ateromatosis (AE) carotídea y contenido de Ca mediante AngioTC. 2. Analizar el grado de calcificación arterial y su relación con la progresión de la ateromatosis carotídea. Secundarios: 3. Evaluar la relación entre calcificación arterial carotídea y descalcificación ósea, así como su posible conexión a través de los factores humorales implicados en la regulación del metabolismo Ca-P. 4. Estudiar un posible mecanismo genético común: relación entre los polimorfismos del gen de la OPG y la progresión de la calcificación en la placa de ateroma. Pacientes y método: Diseño: Cohortes, medidas repetidas. Pacientes: 54 pacientes, neurológicamente asintomáticos con estenosis de la arteria carótida interna (ECI) >50% (eco-Doppler). Determinaciones: Medición del grado de ECI mediante eco-Doppler y proyecciones MIP 2D de AngioTC. Medición del Volumen del molde de contraste y contenido de Ca (AngioTC cuantitativa: Agatston score modificado: volumen de Ca (mm3) x densidad radiológica (unidades Hounsfield, UH) en reconstrucción volumétrica (volume rendering) de la bifurcación carotídea (volumen de contraste entre 2 cm por debajo y 1 cm por encima de la bifurcación [VBif] y su cociente con un segmento de 1 cm en carótida primitiva [VCP]) (n=45). En todos los pacientes se repitió la exploración a los 122 meses para valorar la variación en el contenido de Ca y en el grado de estenosis volumétrica de la bifurcación, como medición indirecta de la progresión/regresión de la AE carotídea. Densitometría ósea de columna y fémur (n=32), (basal y a los 122 meses). Bioquímica y metabolismo Ca-P (Ca, P, vit D, PTH). Determinación de osteopontina (OPN) y osteoprotegerina (OPG) sérica y distribución de 7 SNPs del gen de la OPG seleccionados sobre bases bibiliométricas (n=48). Análisis estadístico: descriptivo (media [DE]); concordancia intra e interobservador (gráficos de Bland-Altman) y coeficiente de correlación intraclase (CCI), precisión eco-Doppler/AngioTC y Volumetría 3D/MIP 2D: sensibilidad (Sens), especificidad (Esp), índice kappa, curvas operador receptor (COR), comparación de medias (prueba T), análisis de regresión uni y multivariable. Resultados: 1. La medición volumétrica de la bifurcación carotídea mostró una concordancia intra e interobservador con un CCI de 0,96 (IC 95%: 0,904-0,985) y 0,94 (IC 95%: 0,822-0,977), respectivamente. El VBif/VCP del grupo de ECI50% (p=0,001). El punto de corte óptimo de la relación VBif/VCP se identificó a partir de la curva COR en 4,1 (Sens=0,75; Esp=0,75, kappa=0,46). 2. La medición mediante AngioTC demostró, a los 12 meses, un aumento del volumen promedio de pared arterial (disminución del volumen de la columna de contraste), respecto al valor basal (475,45 [155,6] mm3xUH vs 501,3 [171,9] mm3xUH, p=0,04), así como un aumento del Ca intraplaca (56,8 [52,3] vs 64,58 [57,8] mm3xUH, p=0,002). El análisis univariable demostró una correlación inversa entre el contenido basal de Ca y progresión de estenosis volumétrica de la bifurcación (r=-0,481; p<0,001). El análisis de regresión múltiple permitió ajustar un modelo de regresión lineal entre la reducción del volumen de la bifurcación (progresión de AE carotídea) y el contenido basal de Ca intraplaca, ajustado por el índice de masa corporal (IMC). 3. Se observó una disminución estadísticamente significativa de la densidad ósea respecto a la determinación basal (2,08 [0,22] vs 2,06 [0,23] g/cm2; p=0,013), así como un aumento del Ca intraplaca respecto a los valores basales (79,2 [55] vs 64,58 [49,2] mm3xUH, p=0,12). Sin embargo, se identificó una correlación positiva entre la variación relativa del contenido de Ca y la variación relativa de la densidad ósea (r=0,574, p=0,003). En otras palabras, una mayor tendencia a la osteoporosis se asoció con una menor tendencia a la progresión del calcio intraplaca. Así mismo, se observó una relación entre los niveles plasmáticos de Vit D y la densitometría basal (r=-0,459, p=0,036) y entre los niveles plasmáticos de HDL-colesterol y la variación relativa, respecto a los valores basales, de la densidad ósea (r=-0,579, p=0,009). El análisis univariable demostró una correlación inversa entre el incremento del contenido de calcio intraplaca y los niveles plasmáticos de vit D (r=0,4; p=0,025) y score Z en fémur (r=0,378; p=0,047). Sólo la concentración de P en orina presentó una correlación positiva moderada con el aumento de Ca intraplaca (r=0,488, p=0,015). Ninguna otra variable, entre los parámetros del metabolismo Ca-P, mostró relación con la calcificación arterial. 4. No se observaron diferencias entre la distribución de los SNPs en los pacientes de la muestra del estudio y el grupo control. Tampoco se observó relación entre el genotipo (SNPs) y la concentración de OPG sérica. Conclusiones: 1. La medición volumétrica de la bifurcación carotídea supone un nuevo concepto basado en la valoración de la carga de placa más que en su efecto hemodinámico o estenosis máxima. Dada su precisión en la detección de variaciones pequeñas de la luz arterial, este método puede ser de especial utilidad en estudios de progresión de placa. 2. Los resultados de este estudio sugieren que un mayor contenido de Ca confiere mayor estabilidad frente a la progresión de la AE carotídea y, eventualmente, a su capacidad para generar sintomatología tromboembólica. 3. Encontramos una tendencia independiente a la progresiva calcificación arterial y descalcificación ósea. Sin embargo, los resultados sugieren una relación temporal directa en la evolución del depósito de calcio en ambas localizaciones, por lo que no es posible descartar que su modulación se rija por mecanismos similares. 4. No se observó una relación estadísticamente significativa entre la distribución de los SNPs analizados y los niveles de la OPG o la calcificación intraplaca en los pacientes estudiados.Background: Quantification and characterization of mineral calcium (Ca) (hydroxyapatite) in the carotid bifurcation with AngioCT, and its relation with neurological symptomatology, in a preliminary case-control study (Miralles et al., Eur J Vasc Endovasc Surg 2006) Constitutes the conceptual basis of the present study. Their results, like those of other publications, suggested a possible protective role for calcium in the development of neurological events. However, its relationship with the progression of carotid atheromatosis has been scarcely analyzed. Objectives: Primary: 1. To design a method of volumetric measurement of carotid atheromatosis (AE) and Ca content by AngioCT. 2. To analyze the degree of arterial calcification and its relation with the progression of carotid atheromatosis. Secondary: 3. To evaluate the relationship between carotid artery calcification and bone decalcification, as well as its possible connection through humoral factors involved in the regulation of Ca-P metabolism. 4 To study a possible common genetic mechanism: relationship between polymorphisms of osteoprotegerin (OPG) gene and the progression of calcification in the atherosclerotic plaque. Patients and method: Design: Cohorts, repeated measures. Patients: 54 asymptomatic patients with internal carotid artery stenosis CAS>50% (duplex scanning). Determinations: Measurement of CAS grade with duplex scanning and MIP 2D projections of AngioCT. Volume measurement of contrast medium and Ca content (quantitative AngioCT: Agatston score: Ca volume (mm3) x radiological density (Hounsfield units, HU) in volume reconstruction of the carotid bifurcation [contrast volume between 2 cm below and 1 cm above the bifurcation (BifV) and its ratio with that from 1 cm segment in common carotid artery (CCV)] (n=45). In all patients, the scans was repeated at 12±2 months to assess the variation in Ca content and the degree of bifurcation volumetric stenosis as an indirect measure of carotid AE progression / regression. Bone and spine densitometry (n=32), where obtained at baseline and after 12±2 months, as well as Biochemistry and Ca-P metabolism parameters (Ca, P, vit D, PTH). Determination of plasma levels of osteopontin (OPN) and osteoprotegerin (OPG) where compared with the distribution of 7 SNPs of the OPG gene selected on bibiliometrics bases (n=48). Statistical analysis: descriptive [mean (SD)]; Intra and interobserver agreement (Bland-Altman plots and intraclass correlation coefficient (ICC), duplex scanning / AngioCT precision and 3D Volumetry / MIP 2D: Sensitivity (S), specificity (E), kappa index, ROC curves, means comparison (T test), univariate and multivariate regression analysis. Results: 1.The volumetric measurement of the carotid bifurcation showed intra and interobserver agreement with a ICC of 0.96 (95% CI: 0.904-0.985) and 0.94 (95% CI: 0.822-0.977), respectively. The BifV/CCV of the CAS > 50% group was 5.2±1.8 vs 3.8 ±1.3 in the CAS >50% group (p=0.001). The optimum cutoff point for the BifV/CCV relation was identified from the ROC curve at 4,1 (S=0.75, E=0.75, kappa=0.46). 2. AngioCT measurement showed, at 12 months, an increase in mean arterial wall volume (decrease in contrast column volume), compared to baseline (475.45 [155.6] mm3xHU vs 501.3 [171.9] mm3xHU, p=0.04), as well as an increase in intraplaque Ca (56.8 [52.3] vs 64.58 [57.8] mm3xHU, p=0.002). Univariate analysis showed an inverse correlation between basal Ca content and progression of bifurcation volumetric stenosis (r=-0.481; p<0.001). The multiple regression analysis allowed to fit a linear regression model between the reduction of bifurcation volume (carotid AE progression) and the baseline intraplaque content of Ca, adjusted for body mass index (BMI). 3. A statistically significant decrease in bone density was observed with respect to the baseline determination (2.08 [0.22] vs 2.06 [0.23] g/cm2, p=0.013), as well as increased intraplaque Ca as compared with baseline values (79.2 [55] vs 64.58 [49.2] mm3xHU, p=0.12). However, a positive correlation was identified between the relative variation of Ca content and the relative variation of bone density (r=0.574, p=0.003). In other words, a greater tendency to osteoporosis was associated with a lower tendency to progression of intraplaque calcium. Likewise, a relationship between Vit D plasma levels and baseline densitometry (r=-0.459, p=0.036) and between plasma HDL-cholesterol levels and the relative variation, relative to baseline values, were observed. Bone density (r=-0.579, p=0.009). The univariate analysis showed an inverse correlation between the basal Ca content and the progression of bifurcation volumetric stenosis (r=-0.481; p<0.001), as well as between the increase in the intra-plaque calcium content and plasma levels of vit D (R=0.4, p=0.025) and femur Z score (r=0.378, p=0.047). Only the urine P concentration presented a moderate positive correlation with the increase of intra-plaque Ca (r=0.488, p=0.015). No other variable, among Ca-P metabolism parameters, was related to arterial calcification. 4. There were no differences between the distribution of SNPs in patients and control group. There was also no relationship between genotype and serum OPG concentration. Conclusions: 1. The volumetric measurement of the carotid bifurcation is a new concept based on the assessment of the plaque load rather than on its hemodynamic effect or maximal stenosis. Given its accuracy in detecting small variations in arterial lumen, this method may be especially useful in plaque progression studies. 2. The results of this study suggest that a higher content of Ca confers greater stability against the progression of carotid AE and, eventually, its capacity to generate symptomatology. 3. We found an independent tendency to progressive arterial calcification and bone decalcification. However, the results suggest a direct temporal relationship in the evolution of the calcium deposit in both locations, so it is not possible to rule out that its modulation is controlled by similar mechanisms. 4. The results are inconclusive with regard to the role of OPG in AE plaque calcification. No significant relationship between the distribution of SNPs analyzed and OPG levels in the studied patients was observed

Negotiating networks of self-employed work: strategies of minority ethnic contractors

Within the increased flexible, contracted work in cities, employment is negotiated through network arrangements characterised by multiplicity, mobility and fluidity. For black and minority ethnic group members, this network labour becomes fraught as they negotiate both their own communities, which can be complex systems of conflicting networks, as well as non-BME networks which can be exclusionary. This discussion explores the networking experiences of BME individuals who are self-employed in portfolio work arrangements in Canada. The analysis draws from a theoretical frame of ‘racialisation’ (Mirchandani and Chan, 2007) to examine the social processes of continually constructing and positioning the Other as well as the self through representations in these networks. These positions and concomitant identities enroll BME workers in particular modes of social production, which order their roles and movement in the changing dynamics of material production in networked employment