Comparing Exposure to Psychosocial Risks: Face-to-Face Work vs. Telework.

BACKGROUND: In recent years, substantial changes have occurred in the work organization and arrangements. One of the main ones has been the popularization of teleworking among non-manual workers. This paper aims to assess the exposure of psychosocial risks among non-manual Spanish wage-earners, depending on the working modality (mainly telework, combining teleworking with onsite work, or onsite work). METHODS: Based on an online survey conducted between April and May 2021, a cross-sectional study was carried out among n=11,519 members of a trade union where Psychosocial Risks (PSR) were measured through COPSOQ Questionnaire Scales. All analyses were performed stratifying by sex. RESULTS: Women who combine telework and face-to-face work (aPR: 1.21; 95%CI 1.07-1.37) and men who mainly telework (aPR: 1.26; 95%CI 1.11-1.43) and that combine (aPR: 1.27; 95%CI 1.11-1.45) are more exposed to quantitative demands than men and women who do not telework. On the other hand, women who telework, either entirely (aPR: 0.89; 95%CI 0.82-0.97) or combining (aPR: 0.89; 95%CI 0.81-0.98), are less exposed to emotional demands than women who do not telework, and the same occurs among men who mainly telework (aPR: 0.84; 95%CI 0.76-0.92). Telework and horizontal or vertical social support are not associated, except for supervisor support among males, nor with work-life conflict. CONCLUSIONS: Except for quantitative demands, employees who combine telework and face-to-face work are less exposed to psychosocial risks than those who mainly telework or work face-to-face only. More studies with a gender and class perspective are needed in this area.

Minerals and trace elements in pregnancy in women with previous bariatric surgery consequences on maternal and foetal health.

BACKGROUND: Bariatric surgery (BS) may decrease the risk of these obesity-related complications; however, due to its effect on nutrient intake and absorption, it can also have adverse consequences on maternal and foetal health. The aim of this study is to describe the evolution of electrolytes and trace elements serum levels throughout pregnancy after BS, according to the surgical technique and to evaluate the effect of nutritional deficiencies on the risk of maternal-foetal complications. METHODS: This is a retrospective observational study of the clinical evolution and maternal-foetal complications in a group of women with pregnancies that occurred after BS. Clinical evolution during pregnancy, body weight, and plasma electrolytes, vitamins, and trace elements, as well as their influence on maternal-foetal outcomes were evaluated. Composite neonatal variable (CNV) was defined to evaluate unfavourable foetal outcome. Published reference values for micronutrients during pregnancy have been used. RESULTS: The study includes data on 164 singleton pregnancies in 91 women. A hundred and twenty-seven pregnancies got to full term. The average birth weight was 2966 (546) g., 26.8% < P10 and 13.8% < P3 of a reference population. New-born of gestations after malabsorptive bariatric surgery had a higher risk of having a percentile of birth weight < P3. Plasma electrolytes, trace elements and vitamins throughout pregnancy showed differences depending on the surgical technique, with lower haemoglobin, ferritin, calcium, zinc, copper, vitamin A and vitamin E in the malabsorptive techniques. A high percentage of deficiency was observed, especially in the third trimester (Hb < 11 g/dl: 31.8%; ferritin < 30 mg/ml: 85.7%; zinc < 50 µg/dl: 32.4%, vitamin D < 30 ng/ml: 75.5% and < 20 ng/ml: 53.3%). A decreased plasma copper in the first trimester or zinc in the third trimester were associated with a lower percentile of new-born birth weight. A higher risk of CNV was observed in predominant malabsorptive BS and in pregnancies that had presented at least one vitamin D level lower than 20 ng/ml throughout pregnancy (30.4% vs. 7.1%, p=0.018). CONCLUSIONS: Trace elements and vitamin deficiencies are common in pregnant women after bariatric surgery, especially of iron, zinc, and vitamin D. These deficiencies might negatively affect foetal development. Further studies are needed to better define the role of micronutrients in maternal-foetal health after bariatric surgery.

Job Insecurity, Mental Health, and General Health Over Time: A Longitudinal Update of a Cross-sectional Study.

OBJECTIVE: The aim of the study is to test the relationship between different conceptualizations of job insecurity and health over time by applying a longitudinal design. METHODS: 543 workers were reinterviewed after 1 year to check if being exposed to job insecurity affected their general and mental health. Robust Poisson regressions were fitted to calculate the incidence rate ratio between job insecurities and two health outcomes. RESULTS: Cognitive job loss insecurity increases the risk of poor mental and general health. Other expressions of job insecurity such as labor market insecurity and working conditions insecurity, as well as affective job insecurity, are not significantly related to health across time. CONCLUSIONS: Caution is needed when interpreting cross-sectional results. Protection against the threat of losing a job would prevent mental health issues and poor general health.

Protective action in the workplace in the time of COVID-19: The role of worker representation.

BACKGROUND: This study addresses the contribution of worker representation to health and safety in the pandemic context. To do so, we examine whether the self-reported presence of representatives in workplaces is associated with the implementation of anti-COVID-19 protective action and with which type of measures their existence is most strongly associated (individual, collective or organizational). The article also explores how the presence of worker representatives and anti-COVID-19 protective measures are distributed according to workers' socio-professional characteristics and company features. METHODS: This is a cross-sectional study based on an online survey conducted in Spain (n = 19,452 workers). Multiple Correspondence Analysis was used for the multivariate description while the association between worker representation and protective measures was assessed by robust Poisson regressions. RESULTS: The maps resulting from the Multiple Correspondence Analysis allow for the identification of patterns of inequalities in protection, with a clear occupational social class divide. The regression models show that protective measures are applied more frequently where worker representatives exist, this association being particularly strong in relation to organizational measures. CONCLUSIONS: The presence of worker representation is systematically associated with a greater presence of protective measures, which could have implications for the reduction of social inequalities resulting from labor-management practices.

Mental health inequalities in times of crisis: evolution between 2005 and 2021 among the Spanish salaried population.

BACKGROUND: Studying the working population's mental health in times of crisis (such as the 2008 recession or the COVID-19 pandemic) is very relevant. This study aims to assess the prevalence of poor mental health among the Spanish salaried population, according to the labour market inequality axes (2005-2021). METHODS: Repeated cross-sectional study by comparing different surveys from 2005, 2010, 2016 and 2021 on workers residing in Spain who had been working in a salaried job during the week preceding the survey. n=7197 (2005), n=4985 (2010), n=1807 (2016) and n=18 870 (2021). OUTCOME VARIABLE: poor mental health (Mental Health Inventory of the 36-item Short Form Health Survey scale). Explanatory variables: gender, age, occupational class and type of contract. Prevalence of poor mental health was estimated for each year by means of logistic regression models with robust clustered SEs, stratifying by the explanatory variables. Additionally, prevalence ratios (PR) were estimated by means of robust Poisson regression models to assess differences between the explanatory variables' categories. All analyses were weighted to address unrepresentativeness. RESULTS: Poor mental health significantly increased in 2021 (55.92%), compared with the previous years of study (15%-17.72%). Additionally, pattern changes were identified on inequality axes in 2021, with better mental health status among older workers (oldest group PR: 0.76; 95% CI 0.71 to 0.8) and permanent workers (PR: 0.9; 95% CI 0.85 to 0.94). CONCLUSION: This study shows a steep worsening of mental health among the salaried population in 2021 compared with previous periods. In 2021, health inequalities have apparently narrowed, although not by improving the disadvantaged groups' mental health but by worsening the typically advantaged groups' mental health.

Delegation and consultation on operational and tactical issues: Any difference in their potentialities for a healthier psychosocial work environment?

BACKGROUND: Despite the growing number of studies on direct participation labor-management practices, little is known about the role of their different discretionary degrees (delegation or consultation) and topics in their relationship with the psychosocial work environment by occupational groups. METHODS: Cross-sectional study on the relationship between direct participation and work-related psychosocial risks (using COPSOQ-ISTAS21 v3) on a representative sample of the salaried and wage-earning employees in Spain (n = 1807). Prevalence ratios were calculated using adjusted Poisson regression models, controlling for 10 other labor-management practices, sex, and age, and stratified by occupational group. RESULTS: The use of direct participation was either associated consistently with a healthier psychosocial work environment (mostly in manual occupations, which presented twice as many positive associations as nonmanual occupations, and of greater strength, mostly in the control and social support dimensions) or there were no significant associations (mostly among nonmanual occupations and in relation to work pace). More frequent and stronger associations were observed when consultation and delegation were used in combination. If used separately, consultation achieved better results among manual occupations and delegation among nonmanual occupations. Direct participation topics were not important for results in manual occupations whereas results were better on tactical (vs. operational) issues in nonmanual occupations. CONCLUSIONS: Direct participation does not change power structure, but it may be a useful intervention at the company level to reduce work-related psychosocial exposures and associated diseases among workers in manual occupations, and consequently for decreasing occupational exposures and health inequalities.

Health outcomes and psychosocial risk exposures among healthcare workers during the first wave of the COVID-19 outbreak.

The aim is to describe the health and psychosocial risk factors of Spanish healthcare workers during the COVID-19 pandemic. METHODS: A cross-sectional study by means of an online questionnaire (April-May 2020). The data comes from the database resulting from the COTS project "Working conditions, insecurity, and health in the context of the COVID-19 pandemic". The sample consisted of 1989 health care workers. RESULTS: Women, young people (doctors and nurses) and the middle-aged (assistants) had poorer health and greater exposure to psychosocial risks. Geriatric assistants were the most-affected occupational group. CONCLUSIONS: gender, occupation, and age are focuses of inequality in the exposure of health care workers to psychosocial risks.

[The third version of COPSOQ-Istas21. An updated international instrument for the workplace.] / La tercera versión de COPSOQ-Istas21. Un instrumento internacional actualizado para la prevención de riesgos psicosociales en el trabajo.

OBJECTIVE: The Copenhagen Psychosocial Questio-nnaire (COPSOQ) is one of the most widely used in research and psychosocial risk assessment in the workplace. The adaptation of the third international COPSOQ version to Spain is described and the evidence of its validity and reliability presented. METHODS: Most of the items were already part of the previous versions I and II. The translation of the new items was done by means of translation/reverse translation. The questionnaire was included in the Psychosocial Risk Survey 2016, a cross-sectional study of a representative sample of the wage-earning population in Spain (N=1,807). Descriptive statistics, internal consistency, floor and ceiling effects and factor structure were analysed. Prevalence Ratios adjusted by age, sex and occupational class (aPR) to mental health, general health and job satisfaction were calculated. Finally, population reference values were calculated for all dimensions of the instrument. RESULTS: The questionnaire showed an excellent factorial structure. All scales, except one, showed α of Cronbach >0.70. Comparing the COPSOQ-Istas21 III scales with their international references, Cronbach's α were higher and the ceiling and floor effects were lower; i.e. Organisational Justice: α=0.85 vs 0.74, ceiling and floor 1.6 and 9.4 vs 3.3 and 12.8. The aPR between all the psychosocial dimensions and the Mental Health, General Health and Job Satisfaction were in the expected direction and showed an association gradient. CONCLUSIONS: COPSOQ-Istas21 version III presents psychometric properties analogous or better than the original in English language, and good indicators of validity and reliability, to be used in research and psychosocial risk assessment at the workplace in Spain.

OBJETIVO: El Copenhagen Psychosocial Questionnaire (COPSOQ) es uno de los más utilizados en investigación y evaluación de riesgos psicosociales en el trabajo. En este artículo se describió la adaptación de la tercera versión internacional a España y se presentaron las pruebas de su validez y fiabilidad. METODOS: La mayoría de los ítems ya formaban parte de las versiones anteriores I y II. La traducción de los nuevos ítems fue realizada mediante traducción/traducción inversa. El cuestionario se incluyó en la Encuesta de Riesgos Psicosociales de 2016, estudio transversal de una muestra representativa de la población asalariada en España (N=1.807). Se analizaron los estadísticos descriptivos, consistencia interna, efectos suelo y techo y estructura factorial. Se calcularon las Razones de Prevalencia ajustadas por edad, sexo y clase ocupacional (aRP) con salud mental, salud general y satisfacción laboral. Finalmente, se calcularon los valores de referencia poblacionales para todas las dimensiones del instrumento. RESULTADOS: El cuestionario mostró una excelente estructura factorial. Todas las escalas, excepto una, mostraron α de Cronbach >0,70. Comparando las escalas de COPSOQ-Istas21 III con sus referentes internacionales, las α de Cronbach fueron más altas y los efectos techo y suelo menores (por ejemplo, Justicia organizacional: α=0,85 vs 0,74, techo y suelo 1,6 y 9,4 vs 3,3 y 12,8). Las aRP entre todas las dimensiones psicosociales y las dimensiones de Salud mental, Salud general y Satisfacción, fueron en la dirección esperada y mostraron un gradiente de asociación. CONCLUSIONES: COPSOQ-Istas21 versión III presenta propiedades psicométricas análogas o mejores al original en lengua inglesa y buenos indicadores de validez y fiabilidad para ser usado en investigación y evaluación de riesgos psicosociales laborales en España.

New Uses for the Personal Glucose Meter: Detection of Nucleic Acid Biomarkers for Prostate Cancer Screening.

A personal glucose meter (PGM)-based method for quantitative detection of a urinary nucleic acid biomarker in prostate cancer screening, the so-called PCA3, is reported herein. A sandwich-type genoassay is conducted on magnetic beads to collect the target from the sample by specific hybridization, making the assay appropriate for PCA3 detection in biological fluids. The success of the method hinges on the use of alkaline phosphatase (ALP) to link the amount of nucleic acid biomarker to the generation of glucose. In particular, specifically attached ALP molecules hydrolyze D-glucose-1-phosphate into D-glucose, thus enabling the amplification of the recorded signal on the personal glucose meter. The developed genoassay exhibits good sensitivity (3.3 ± 0.2 mg glucose dL-1 pM-1) for PCA3, with a dynamic range of 5 to 100 pM and a quantification limit of 5 pM. Likewise, it facilitates point-of-care testing of nucleic acid biomarkers by using off-the-shelf PGM instead of complex instrumentation involved in traditional laboratory-based tests.

Acute renal failure in COVID-19 patients on mechanical ventilation / Insuficiencia renal aguda en pacientes COVID-19 en ventilación mecánica

COVID-19 Community acquired pneumonía is a recent and frequent cause of admission in European intensive care units. Currently, there are many open questions regarding the management and prognostic factors of these patients. Among them, its association with acute renal failure in patients on mechanical ventilation. Analysis of acute renal failure in COVID-19 patients on mechanical ventilation. Prognosis and factors related to its development. Retrospective observational study carried out in the intensive care unit of a University Hospital during the COVID-19 pandemic. We analysed patients admitted to the ICU with the diagnosis of Respiratory Failure due to Pneumonia COVID-19 between 6/3/2020 and 21/4/2020. Demographic data (age, sex), APACHE II, comorbidities, analytical data (ferritin, total bilirubin), length of stay, treatments administered (mechanical ventilation, muscle relaxant, vasoactive drugs, prone) and its association to acute renal failure were analysed. 67 patients received complete treatment in our hospital. Length of stay (days) 14.1 ± 10, average age 60 years, APACHE II 14.3 ± 5.2, 67.2% males. Maximum creatinine mean value (mg/dl) 1.48 ± 1.26, Maximum ferritin mean value (ng/ml) 2,310 ± 3,322, Maximum total bilirubin mean value (mg/dl) 2 ± 2.2. 100% of the patients required mechanical ventilation. 65.7% prone positioning, 74.6% neuromuscular blockers and 98.5% required vasoactive drugs. Establishing renal failure as creatinine values greater than 1.2 mg/dl. Patients with maximum creatinine above 1.2 mg/dl presented average values of bilirubin and ferritin higher than those with values under 1.2 mg/dl (P < 0.05). The presence of renal failure was also statistically significantly associated with sex (male), presence of dyslipidaemia, and mortality. In our sample, we have associated acute renal failure with higher ferritin valúes. Likewise, we have observed higher creatinine valúes in the group of non-survivors, those with dyslipidaemia and men, with statistical signification.

La neumonía adquirida en la comunidad COVID-19 es una causa reciente y frecuente de ingreso en las unidades de cuidados intensivos europeos. Actualmente, hay muchas preguntas abiertas con respecto al manejo y los factores pronósticos de estos pacientes. Entre ellos, su asociación con insuficiencia renal aguda en pacientes en ventilación mecánica. Análisis de insuficiencia renal aguda en pacientes con COVID-19 en ventilación mecánica. Pronóstico y factores relacionados con su desarrollo. Estudio observacional retrospectivo realizado en la unidad de cuidados intensivos de un Hospital Universitario durante la pandemia de COVID-19. Analizamos los pacientes ingresados en UCI con el diagnóstico de insuficiencia respiratoria por neumonía COVID-19 entre el 3/6/2020 y el 21/4/2020. Se analizaron datos demográficos (edad, sexo), APACHE II, comorbilidades, datos analíticos (ferritina, bilirrubina total), tiempo de estancia, tratamientos administrados (ventilación mecánica, relajante muscular, fármacos vasoactivos, prono) y su asociación con insuficiencia renal aguda. 67 pacientes recibieron tratamiento completo en nuestro hospital. Duración de la estancia (días) 14,1 ± 10, edad media 60 años, APACHE II 14,3 ± 5,2, 67,2% varones. Valor medio máximo de creatinina (mg/dl) 1,48 ± 1,26, valor medio máximo de ferritina (ng/ml) 2.310 ± 3.322, valor medio máximo de bilirrubina total (mg/dl) 2 ± 2,2. El 100% de los pacientes requirió ventilación mecánica. El 65,7% en decúbito prono, el 74,6% bloqueantes neuromusculares y el 98,5% requirieron fármacos vasoactivos. Estableciendo la insuficiencia renal como valores de creatinina superiores a 1,2 mg/dl, los pacientes con creatinina máxima superior a 1,2 mg/dl presentaron valores medios de bilirrubina y ferritina superiores a aquellos con valores menores a 1,2 mg/dl, de forma estadísticamente significativa. La presencia de fallo renal, también se asoció de forma estadísticamente significativa al sexo hombre, la presencia de dislipidemia como antecedente personal de interés y a la mortalidad. En nuestra muestra hemos asociado la insuficiencia renal aguda con valores más elevados de ferritina. Asimismo, hemos observado mayores valores de creatinina en el grupo de no supervivientes, los que presentan dislipidemia y los hombres, con significación estadística.

Lysophosphatidic acid receptor type 2 activation contributes to secondary damage after spinal cord injury in mice.

Lysophosphatidic acid (LPA) is an extracellular lipid mediator involved in many physiological functions by signaling through six known G-protein-coupled receptors (LPA1-LPA6). In the central nervous system (CNS), LPA mediates a wide range of effects, including neural progenitor cell physiology, astrocyte and microglia activation, neuronal cell death, axonal retraction, and contributions to pain, schizophrenia and hydrocephalus. We recently reported that LPA-LPA1 signaling mediates functional deficits and myelin loss after spinal cord injury (SCI). Here, we provide clear evidence on the deleterious contribution of another LPA receptor, LPA2, to myelin loss after SCI. We found that LPA2 is constitutively expressed in the spinal cord parenchyma and its transcripts were up-regulated after contusion injury, in part, by microglial cells. We also found that the demyelinating lesion triggered by intraspinal injection of LPA into the undamaged spinal cord was markedly reduced in the lack of LPA2. Similarly, LPA2 deficient mice showed enhanced motor skills and myelin sparing after SCI. To gain insights into the detrimental actions of LPA2 in spinal cord we performed cell culture studies. These experiments revealed that, similar to LPA1, activation of microglia LPA2 led to oligodendrocyte cell death. Moreover, we also found that the cytotoxic effects underlaying microglial LPA-LPA2 axis were mediated by the release of purines by microglia and the activation of P2X7 receptor on oligodendrocytes. Overall, this study provides new mechanistic insights into how LPA contributes to SCI physiopathology, and suggest that targeting LPA2 could be a novel therapeutic approach for the treatment of acute SCI.

One-Step Synthesis of Hybrid Liquid-Crystal ZnO Nanoparticles: Existence of a Critical Temperature Associated with the Anisotropy of the Nanoparticles.

Zinc oxide nanoparticles were obtained from the hydrolysis of an organometallic precursor in pure hexadecylamine. Interestingly, we demonstrate that the final (anisotropic or isotropic) shape of the nanoparticles is strongly correlated to the existence of a critical temperature. This suggests that the organization of the fatty amines is a paramount parameter in this synthesis. Moreover, the final hybrid ZnO materials systematically exhibit a liquid-crystal smectic phase, whereas no liquid-crystal phase was observed in the pristine reaction media. This simple process is, therefore, a direct and straightforward method to synthesize liquid-crystal hybrid materials.

Effects of the Post-Spinal Cord Injury Microenvironment on the Differentiation Capacity of Human Neural Stem Cells Derived from Induced Pluripotent Stem Cells.

Spinal cord injury (SCI) causes loss of neural functions below the level of the lesion due to interruption of spinal pathways and secondary neurodegenerative processes. The transplant of neural stem cells (NSCs) is a promising approach for the repair of SCI. Reprogramming of adult somatic cells into induced pluripotent stem cells (iPSCs) is expected to provide an autologous source of iPSC-derived NSCs, avoiding the immune response as well as ethical issues. However, there is still limited information on the behavior and differentiation pattern of transplanted iPSC-derived NSCs within the damaged spinal cord. We transplanted iPSC-derived NSCs, obtained from adult human somatic cells, into rats at 0 or 7 days after SCI, and evaluated motor-evoked potentials and locomotion of the animals. We histologically analyzed engraftment, proliferation, and differentiation of the iPSC-derived NSCs and the spared tissue in the spinal cords at 7, 21, and 63 days posttransplant. Both transplanted groups showed a late decline in functional recovery compared to vehicle-injected groups. Histological analysis showed proliferation of transplanted cells within the tissue and that cells formed a mass. At the final time point, most grafted cells differentiated to neural and astroglial lineages, but not into oligodendrocytes, while some grafted cells remained undifferentiated and proliferative. The proinflammatory tissue microenviroment of the injured spinal cord induced proliferation of the grafted cells and, therefore, there are possible risks associated with iPSC-derived NSC transplantation. New approaches are needed to promote and guide cell differentiation, as well as reduce their tumorigenicity once the cells are transplanted at the lesion site.

Ordering of protein and water molecules at their interfaces with chitin nano-crystals.

Synchrotron X-ray diffraction was applied to study the structure of biogenic α-chitin crystals composing the tendon of the spider Cupiennius salei. Measurements were carried out on pristine chitin crystals stabilized by proteins and water, as well as after their deproteinization and dehydration. We found substantial shifts (up to Δq/q=9% in the wave vector in q-space) in the (020) diffraction peak position between intact and purified chitin samples. However, chitin lattice parameters extracted from the set of reflections (hkl), which did not contain the (020)-reflection, showed no systematic variation between the pristine and the processed samples. The observed shifts in the (020) peak position are discussed in terms of the ordering-induced modulation of the protein and water electron density near the surface of the ultra-thin chitin fibrils due to strong protein/chitin and water/chitin interactions. The extracted modulation periods can be used as a quantitative parameter characterizing the interaction length.

Activation of Lysophosphatidic Acid Receptor Type 1 Contributes to Pathophysiology of Spinal Cord Injury.

Lysophosphatidic acid (LPA) is an extracellular lipid mediator involved in many physiological functions that signals through six known G-protein-coupled receptors (LPA1-LPA6). A wide range of LPA effects have been identified in the CNS, including neural progenitor cell physiology, astrocyte and microglia activation, neuronal cell death, axonal retraction, and development of neuropathic pain. However, little is known about the involvement of LPA in CNS pathologies. Herein, we demonstrate for the first time that LPA signaling via LPA1 contributes to secondary damage after spinal cord injury. LPA levels increase in the contused spinal cord parenchyma during the first 14 d. To model this potential contribution of LPA in the spinal cord, we injected LPA into the normal spinal cord, revealing that LPA induces microglia/macrophage activation and demyelination. Use of a selective LPA1 antagonist or mice lacking LPA1 linked receptor-mediated signaling to demyelination, which was in part mediated by microglia. Finally, we demonstrate that selective blockade of LPA1 after spinal cord injury results in reduced demyelination and improvement in locomotor recovery. Overall, these results support LPA-LPA1 signaling as a novel pathway that contributes to secondary damage after spinal cord contusion in mice and suggest that LPA1 antagonism might be useful for the treatment of acute spinal cord injury. SIGNIFICANCE STATEMENT: This study reveals that LPA signaling via LPA receptor type 1 activation causes demyelination and functional deficits after spinal cord injury.

Mesomorphic ionic hyperbranched polymers: effect of structural parameters on liquid-crystalline properties and on the formation of gold nanohybrids.

Branched thermotropic liquid crystals were successfully obtained from ionic interactions between hyperbranched polyamidoamine and sodium dodecylsulfate. These complexes present columnar rectangular and lamellar thermotropic mesophases as demonstrated by polarized optical microscopy, differential scanning calorimetry, and small-angle X-ray scattering. The relationships between the structural characteristics of the polymers (size of the hyperbranched core, hyperbranched or dendritic nature of the core, and substitution ratio) and the mesomorphic properties were studied. In situ formation of gold nanoparticles was then performed. The templating effect of the liquid crystal mesophase resulted in the formation of isotropic nanoparticles, the size of which was dictated by the local organization of the mesophase and by the molar mass of the hyperbranched complex.

Structural and mechanical properties of the arthropod cuticle: comparison between the fang of the spider Cupiennius salei and the carapace of American lobster Homarus americanus.

Most biological materials are nanocomposites characterized by a multi-level structural hierarchy. Particularly, the arthropod cuticle is a chitin-based composite material where the mechanical properties strongly depend on both molecular chitin/protein properties, and the structural arrangement of chitin-fibrils within the protein matrix. Here materials properties and structural organization of two types of cuticle from distantly related arthropods, the wandering spider Cupiennius salei and American lobster Homarus americanus were studied using nanoindentation and X-ray diffraction. The structural analysis of the two types of cuticle including the packing and alignment of chitin-fibrils is supported by Monte Carlo simulations of the experimental X-ray data, thereby regions of parallel and rotated fibril arrangement can be clearly distinguished. The tip of the spider fang which is used to inject venom into the prey was found to be considerably harder than the lobster carapace, while its stiffness is slightly lower.

[Psychosocial risk exposure among wage earning population in Spain (2004-05): reference values of the 21 dimensions of COPSOQ ISTAS21 questionnaire]. / Exposición a riesgos psicosociales entre la población asalariada en España (2004-05): valores de referencia de las 21 dimensiones del cuestionario COPSOQ ISTAS21.

BACKGROUND: Reference values of all the 21 psychosocial scales or dimensions (73 items) of the psychosocial risk assessment questionnaire COPSOQ ISTAS21 are computed from a representative sample of the wage earning population in Spain. METHODS: Representative sample of the Spanish wage-earning population, n=7,612. The sampling was multi-stage by conglomerates. The information was obtained by the administration of a standardized questionnaire in the household during 2004-2005. All 21 scales were standardized and three punctuation levels were established and labelled as 'more favourable to health (or green)', 'intermediate (or yellow)' and 'more unfavourable to health (or red)' according two criteria: 1) to obtain groups that follow a tertiles theoretical distribution and 2) to get the 'red' and 'green' groups as equilibrated as possible. RESULTS: Response rate was 60. Predictability dimension showed the wider difference between 'green' and 'red' proportions (7.14). Role clarity concentred the 35.06 % of population between 100 and 93.75 points, and Sense of community the 29.6% between 100 and 91.67. Double presence and hiding emotions grouped the 34.02% and the 27.74% % of population between 0 and 12.5 points, respectively. CONCLUSIONS: 2005 upgraded representative reference values of the 21 COPSOQ ISTAS21 psychosocial dimensions for the wage earning population in Spain are available, necessary premise to diagnose risk situations and prioritize the needed preventive actions at company level.