How the availability and adequacy of social support affect the general mental health of Swedish police officers.

Police work is stressful. A protective function against work stress and harm to mental health is social support, either within or outside work. This cross-sectional study analyzes the associations of quantitative (availability) and qualitative (adequacy) aspects of social support with general mental health among Swedish police officers. A total of 728 officers responded to a national survey. Bivariate analyses (t-test and chi square) identified continuous and categorical variables (respectively) statistically significantly associated with sex and social support. Pearson correlation coefficient was provided to indicate the associations between general mental health and different types of social support. Sex-stratified logistic regression modeling calculated crude and adjusted odds ratios (OR) with 95% confidence intervals (CI) and assessed the relationships between different types of social support, sociodemographic variables and general mental health. The findings show that low adequacy of attachment is associated with poorer mental health among female officers, although female officers also reported higher availability of both social interaction and attachment compared to male officers. We found an association between low work-related social support and poorer mental health among single male police officers. Moreover, police officers who worked shifts, were younger, had less work experience, and/or had no children reported higher availability of attachment, whereas older police officers reported higher adequacy of social interaction compared to younger police officers. Variation in the quantity and quality of close social relationships seems to be important to mental health. Police organizations need to be aware of this in their efforts to make the work environment more supportive. Social support might create an environment where officers feel more comfortable discussing their mental health concerns and seeking assistance.

A comparative study of stress experienced by Swedish and Norwegian police officers.

Introduction: Police officers work in a variable environment under different circumstances and often involves stressful situations. This include working irregular hours, ongoing exposure to critical incidents, confrontations and violence. community police officers are mainly out in the society and have daily contact with the general public. critical incidents can also consist of being criticized and stigmatized as a police officer, both from the public but also lack of support from their own organization. There is evidence on negative impacts of stress on police officers. However, knowledge about the nature of police stress and its various types is insufficient. It is assumed that there are common stress factors which are universal among all police officers in different contexts but there is a lack of comparative studies to provide empirical evidence. The aim of this study is to compare different types of stress among police officers in Norway and Sweden and how the pattern of experiencing stress has changed over time in these countries. Methods: The study population consisted of patrolling police officers from 20 local police districts or units in all seven regions in Sweden (n = 953) and patrolling police officers from four police districts in Norway (n = 678). A 42-item Police Stress Identification Questionnaire was used to measure the stress level. Results: The findings show differences in types of stressful events as well as its severity among police officers in Sweden and Norway. The level of stress decreased over time among Swedish police officers whereas it showed no change or even an increase among the Norwegian participants. Discussion: The results of this study are relevant for policy-makers, police authorities and lay police officers in each country to tailor their efforts to prevent stress among police officers.

Job satisfaction among Swedish police officers: The role of work-related stress, gender-based and sexual harassment.

The aim of this cross-sectional study is to increase our understanding of job satisfaction in Swedish police officers by taking into account work-related stress, and sexual and gender-based harassment. Data were collected from 152 police officers working in vulnerable areas in Stockholm using sociodemographic questions, the Police Stress Identification Questionnaire (PSIQ), Sexual and gender-based harassment questions, and Job Descriptive Index (JDI). The obtained results indicated that male and female police officers reported the highest satisfaction in "people on your present job." The lowest score of job satisfaction in both male and female police officers was related to "opportunity for promotion" and then "pay." There were no significant differences in the subscales of job satisfaction between male and female police officers. The older and more experienced officers, the less satisfaction was reported in "job in general" and more satisfaction reported in "pay." Comparing job satisfaction between patrol officers and those officers who worked in internal services showed police patrol officers had higher job satisfaction in "job in general," "work in the present job," "opportunity for promotion" and "supervision" compared to their counterparts in internal services. There were not any significant differences between the subscales of job satisfaction between male and female police officers. There was not any significant association between job satisfaction subscales and having experience of sexual or gender-based harassment. Among various subscales of police stressors, organizational stress was in negative relation with three domains of job satisfaction; "job in general," "pay" and "supervision." Also, hierarchical multiple regression analyses showed organizational stress was most often of predictive impact related to various job satisfaction domains in police officers.

Immunoassays on thiol-ene synthetic paper generate a superior fluorescence signal.

The fluorescence-based detection of biological complexes on solid substrates is widely used in microarrays and lateral flow tests. Here, we investigate thiol-ene micropillar scaffold sheets ("synthetic paper") as the solid substrate in such assays. Compared to state-of-the-art glass and nitrocellulose substrates, assays on synthetic paper provide a stronger fluorescence signal, similar or better reproducibility, lower limit of detection (LOD), and the possibility of working with lower immunoreagent concentrations. Using synthetic paper, we detected the antibiotic enrofloxacin in whole milk with a LOD of 1.64 nM, which is on par or better than the values obtained with other common tests, and much lower than the maximum level allowed by European Union regulations. The significance of these results lays in that they indicate that synthetically-derived microstructured substrate materials have the potential to improve the performance of diagnostic assays.

Synthetic Paper Separates Plasma from Whole Blood with Low Protein Loss.

The separation of plasma from whole blood is the first step in many diagnostic tests. Point-of-care tests often rely on integrated plasma filters, but protein retention in such filters limits their performance. Here, we investigate plasma separation on interlocked micropillar scaffolds ("synthetic paper") by the local agglutination of blood cells coupled with the capillary separation of the plasma. We separated clinically relevant volumes of plasma with high efficiency in a separation time on par with that of state of the art techniques. We investigated different covalent and noncovalent surface treatments (PEGMA, HEMA, BSA, O2 plasma) on our blood filter and their effect on protein recovery and identified O2 plasma treatment and 7.9 µg/cm2 agglutination antibody as most suitable treatments. Using these treatments, we recovered at least 82% of the blood plasma proteins, more than with state-of-the-art filters. The simplicity of our device and the performance of our approach could enable better point-of-care tests.

Droplet leaping governs microstructured surface wetting.

Microstructured surfaces that control the direction of liquid transport are not only ubiquitous in nature, but they are also central to technological processes such as fog/water harvesting, oil-water separation, and surface lubrication. However, a fundamental understanding of the initial wetting dynamics of liquids spreading on such surfaces is lacking. Here, we show that three regimes govern microstructured surface wetting on short time scales: spread, stick, and contact line leaping. The latter involves establishing a new contact line downstream of the wetting front as the liquid leaps over specific sections of the solid surface. Experimental and numerical investigations reveal how different regimes emerge in different flow directions during wetting of periodic asymmetrically microstructured surfaces. These insights improve our understanding of rapid wetting in droplet impact, splashing, and wetting of vibrating surfaces and may contribute to advances in designing structured surfaces for the mentioned applications.

High-Yield Passive Plasma Filtration from Human Finger Prick Blood.

Whole-blood microsampling provides many benefits such as remote, patient-centric, and minimally invasive sampling. However, blood plasma, and not whole blood, is the prevailing matrix in clinical laboratory investigations. The challenge with plasma microsampling is to extract plasma volumes large enough to reliably detect low-concentration analytes from a small finger prick sample. Here we introduce a passive plasma filtration device that provides a high extraction yield of 65%, filtering 18 µL of plasma from 50 µL of undiluted human whole blood (hematocrit 45%) within less than 10 min. The enabling design element is a wedge-shaped connection between the blood filter and the hydrophilic bottom surface of a capillary channel. Using finger prick and venous blood samples from more than 10 healthy volunteers, we examined the filtration kinetics of the device over a hematocrit range of 35-55% and showed that 73 ± 8% of the total protein content was successfully recovered after filtration. The presented plasma filtration device tackles a major challenge toward patient-centric blood microsampling by providing high-yield plasma filtration, potentially allowing reliable detection of low-concentration analytes from a blood microsample.

Capillary pumping independent of the liquid surface energy and viscosity.

Capillary pumping is an attractive means of liquid actuation because it is a passive mechanism, i.e., it does not rely on an external energy supply during operation. The capillary flow rate generally depends on the liquid sample viscosity and surface energy. This poses a problem for capillary-driven systems that rely on a predictable flow rate and for which the sample viscosity or surface energy are not precisely known. Here, we introduce the capillary pumping of sample liquids with a flow rate that is constant in time and independent of the sample viscosity and sample surface energy. These features are enabled by a design in which a well-characterized pump liquid is capillarily imbibed into the downstream section of the pump and thereby pulls the unknown sample liquid into the upstream pump section. The downstream pump geometry is designed to exert a Laplace pressure and fluidic resistance that are substantially larger than those exerted by the upstream pump geometry on the sample liquid. Hence, the influence of the unknown sample liquid on the flow rate is negligible. We experimentally tested pumps of the new design with a variety of sample liquids, including water, different samples of whole blood, different samples of urine, isopropanol, mineral oil, and glycerol. The capillary filling speeds of these liquids vary by more than a factor 1000 when imbibed to a standard constant cross-section glass capillary. In our new pump design, 20 filling tests involving these liquid samples with vastly different properties resulted in a constant volumetric flow rate in the range of 20.96-24.76 µL/min. We expect this novel capillary design to have immediate applications in lab-on-a-chip systems and diagnostic devices.

Capillary Pumping Independent of Liquid Sample Viscosity.

Capillary flow is a dominating liquid transport phenomenon on the micro- and nanoscale. As described at the beginning of the 20th century, the flow rate during imbibition of a horizontal capillary tube follows the Washburn equation, i.e., decreases over time and depends on the viscosity of the sample. This poses a problem for capillary driven systems that rely on a predictable flow rate and where the liquid viscosity is not precisely known. Here we introduce and successfully experimentally verify the first compact capillary pump design with a flow rate constant in time and independent of the liquid viscosity that can operate over an extended period of time. We also present a detailed theoretical model for gravitation-independent capillary filling, which predicts the novel pump performance to within measurement error margins, and in which we, for the first time, explicitly identify gas inertia dominated flow as a fourth distinct flow regime in capillary pumping. These results are of potential interest for a multitude of applications and we expect our results to find most immediate applications within lab-on-a-chip systems and diagnostic devices.

Leak-tight vertical membrane microvalves.

Pneumatic microvalves are fundamental control components in a large range of microfluidic applications. Their key performance parameters are small size, i.e. occupying a minimum of microfluidic real estate, low flow resistance in the open state, and leak-tight closing at limited control pressures. In this work we present the successful design, realization and evaluation of the first leak-tight, vertical membrane, pneumatic microvalves. The realization of the vertical membrane microvalves is enabled by a novel dual-sided molding method for microstructuring monolithic 3D microfluidic networks in PDMS in a single step, eliminating the need for layer-to-layer alignment during bonding. We demonstrate minimum lateral device features down to 20-30 µm in size, and vertical via density of ∼30 000 per cm(2), which provides significant gains in chip real estate compared to previously reported PDMS manufacturing methods. In contrast to horizontal membrane microvalves, there are no manufacturing restrictions on the cross-sectional geometry of the flow channel of the vertical membrane microvalves. This allows tuning the design towards lower closing pressure or lower open state flow resistance compared to those of horizontal membrane microvalves.

Synthetic microfluidic paper: high surface area and high porosity polymer micropillar arrays.

We introduce Synthetic Microfluidic Paper, a novel porous material for microfluidic applications that consists of an OSTE polymer that is photostructured in a well-controlled geometry of slanted and interlocked micropillars. We demonstrate the distinct benefits of Synthetic Microfluidic Paper over other porous microfluidic materials, such as nitrocellulose, traditional paper and straight micropillar arrays: in contrast to straight micropillar arrays, the geometry of Synthetic Microfluidic Paper was miniaturized without suffering capillary collapse during manufacturing and fluidic operation, resulting in a six-fold increased internal surface area and a three-fold increased porous fraction. Compared to commercial nitrocellulose materials for capillary assays, Synthetic Microfluidic Paper shows a wider range of capillary pumping speed and four times lower device-to-device variation. Compared to the surfaces of the other porous microfluidic materials that are modified by adsorption, Synthetic Microfluidic Paper contains free thiol groups and has been shown to be suitable for covalent surface chemistry, demonstrated here for increasing the material hydrophilicity. These results illustrate the potential of Synthetic Microfluidic Paper as a porous microfluidic material with improved performance characteristics, especially for bioassay applications such as diagnostic tests.

The effect of drying on the homogeneity of DBS.

BACKGROUND: Inhomogeneous sample distribution in DBS is a problem for accurate quantitative analysis of DBS, and has often been explained by chromatographic effects. RESULTS: We present a model describing formation of inhomogeneous DBS during drying of the spot caused by higher evaporation rates of water at the edge as compared with the center. Color intensity analysis shows that the relative humidity and DBS card position affect the homogeneity of DBS. CONCLUSION: The so-called 'coffee-stain effect' explains the typical distribution pattern of analytes with higher concentrations measured along the edge of DBS as compared with the center. The driving mechanism and potential influencing factors should be considered when addressing the inhomogeneity of DBS in the future.

Unaccompanied Asylum-Seeking Refugee Children's Forced Repatriation: Social Workers' and Police Officers' Health and Job Characteristics.

During the past ten years the number of unaccompanied asylum-seeking refugee children has dramatically increased in Sweden. Some of them are permitted to stay in the receiving country, but some are forced back to their country of origin. Social workers and police officers are involved in these forced repatriations, and such complex situations may cause stressful working conditions. This study aimed to bridge the gap in knowledge of the relationship between general mental health and working with unaccompanied asylum-seeking refugee children who are due for forced repatriation. In addition, the role of psychosocial job characteristics in such relationships was investigated. A questionnaire including sociodemographic characteristics, the Swedish Demand-Control-Support Questionnaire, and the 12-item General Mental Health Questionnaire were distributed nationally. Univariate and multivariable regression models were used. Poorer mental health was associated with working with unaccompanied asylum-seeking refugee children among social workers but not among police officers. Psychological job demand was a significant predictor for general mental health among social workers, while psychological job demand, decision latitude, and marital status were predictors among police officers. Findings are discussed with special regard to the context of social work and police professions in Sweden.

Microfluidic-based isolation of bacteria from whole blood for sepsis diagnostics.

Blood-stream infections (BSI) remain a major health challenge, with an increasing incidence worldwide and a high mortality rate. Early treatment with appropriate antibiotics can reduce BSI-related morbidity and mortality, but success requires rapid identification of the infecting organisms. The rapid, culture-independent diagnosis of BSI could be significantly facilitated by straightforward isolation of highly purified bacteria from whole blood. We present a microfluidic-based, sample-preparation system that rapidly and selectively lyses all blood cells while it extracts intact bacteria for downstream analysis. Whole blood is exposed to a mild detergent, which lyses most blood cells, and then to osmotic shock using deionized water, which eliminates the remaining white blood cells. The recovered bacteria are 100% viable, which opens up possibilities for performing drug susceptibility tests and for nucleic-acid-based molecular identification.

Inertial microfluidics in parallel channels for high-throughput applications.

Passive particle focusing based on inertial microfluidics was recently introduced as a high-throughput alternative to active focusing methods that require an external force-field to manipulate particles. In this study, we introduce inertial microfluidics in flows through straight, multiple parallel channels. The scalable, single inlet and two outlet, parallel channel system is enabled by a novel, high-density 3D PDMS microchannel manufacturing technology, mediated via a targeted inhibition of PDMS polymerization. Using single channels, we first demonstrate how randomly distributed particles can be focused into the centre position of the channel in flows through low aspect ratio channels and can be effectively fractionated. As a proof of principle, continuous focusing and filtration of 10 µm particles from a suspension mixture using 4- and 16-parallel-channel devices with a single inlet and two outlets are demonstrated. A filtration efficiency of 95-97% was achieved at throughputs several orders of magnitude higher than previously shown for flows through straight channels. The scalable and low-footprint focusing device requiring neither external force fields nor mechanical parts to operate is readily applicable for high-throughput focusing and filtration applications as a stand-alone device or integrated with lab-on-a-chip systems.

Biomarkers of extracellular matrix metabolism (MMP-9 and TIMP-1) and risk of stroke, myocardial infarction, and cause-specific mortality: cohort study.

OBJECTIVE: Turnover of the extracellular matrix in all solid organs is governed mainly by a balance between the degrading matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). An altered extracellular matrix metabolism has been implicated in a variety of diseases. We investigated relations of serum levels of MMP-9 and TIMP-1 to mortality risk from an etiological perspective. DESIGN: The prospective Uppsala Longitudinal Study of Adult Men (ULSAM) cohort, followed from 1991-1995 for up to 18.1 years. A random population-based sample of 1,082 71-year-old men, no loss to follow-up. Endpoints were all-cause (n = 628), cardiovascular (n = 230), non-cardiovascular (n = 398) and cancer mortality (n = 178), and fatal or non-fatal myocardial infarction (n = 138) or stroke (n = 163). RESULTS: Serum MMP-9 and TIMP-1 levels were associated with risk of all-cause mortality (Cox proportional hazard ratio [HR] per standard deviation 1.10, 95% confidence interval [CI] 1.03-1.19; and 1.11, 1.02-1.20; respectively). TIMP-1 levels were mainly related to risks of cardiovascular mortality and stroke (HR per standard deviation 1.22, 95% CI 1.09-1.37; and 1.18, 1.04-1.35; respectively). All relations except those of TIMP-1 to stroke risk were attenuated by adjustment for cardiovascular disease risk factors. Relations in a subsample without cardiovascular disease or cancer were similar to those in the total sample. CONCLUSION: In this community-based cohort of elderly men, serum MMP-9 and TIMP-1 levels were related to mortality risk. An altered extracellular matrix metabolism may be involved in several detrimental pathways, and circulating MMP-9 or TIMP-1 levels may be relevant markers thereof.

Relations of serum MMP-9 and TIMP-1 levels to left ventricular measures and cardiovascular risk factors: a population-based study.

BACKGROUND: Extracellular matrix remodeling is a hallmark of pathological left ventricular (LV) hypertrophy and heart failure. This process is tightly controlled by the degrading matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). We hypothesized that circulating MMP-9 and TIMP-1 levels are altered already in persons with the signs of LV remodeling that forego clinical heart failure. DESIGN: Cross-sectional study in the Prospective Investigation of the Vasculature in Uppsala Seniors, a community-based cohort of 891 70-year-old men and women free from valvular disease, heart failure, and myocardial infarction. METHODS: We examined relations of serum MMP-9 and TIMP-1 to echocardiographic LV geometry and function. All models were adjusted for sex, height, intra-arterial systolic and diastolic blood pressures, antihypertensive medication use, and serum freezer time. RESULTS: Serum TIMP-1 was positively related to LV mass and wall thickness (r=0.15, P<0.0001 and r=0.16, P<0.0001, respectively), with a 32 g higher LV mass and 2.2 mm thicker walls in the fourth compared with the first quartile of serum TIMP-1. Serum TIMP-1 was also inversely related to LV ejection fraction (r=-0.10, P=0.009), but not to LV dimension or diastolic function indices. Serum MMP-9 was only weakly related to LV wall thickness and isovolumic relaxation time (r=0.08, P=0.04 and r=-0.08, P=0.04). CONCLUSION: In this large population-based sample, serum TIMP-1 levels were related to LV mass, wall thickness, and inversely to systolic function. This may imply that extracellular matrix remodeling is involved already in the earliest stages of the process leading to heart failure.