Alternative nano-lithographic tools for shell-isolated nanoparticle enhanced Raman spectroscopy substrates.

Chemically synthesized metal nanoparticles (MNPs) have been widely used as surface-enhanced Raman spectroscopy (SERS) substrates for monitoring catalytic reactions. In some applications, however, the SERS MNPs, besides being plasmonically active, can also be catalytically active and result in Raman signals from undesired side products. The MNPs are typically insulated with a thin (∼3 nm), in principle pin-hole-free shell to prevent this. This approach, which is known as shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS), offers many advantages, such as better thermal and chemical stability of the plasmonic nanoparticle. However, having both a high enhancement factor and ensuring that the shell is pin-hole-free is challenging because there is a trade-off between the two when considering the shell thickness. So far in the literature, shell insulation has been successfully applied only to chemically synthesized MNPs. In this work, we alternatively study different combinations of chemical synthesis (bottom-up) and lithographic (top-down) routes to obtain shell-isolated plasmonic nanostructures that offer chemical sensing capabilities. The three approaches we study in this work include (1) chemically synthesized MNPs + chemical shell, (2) lithographic substrate + chemical shell, and (3) lithographic substrate + atomic layer deposition (ALD) shell. We find that ALD allows us to fabricate controllable and reproducible pin-hole-free shells. We showcase the ability to fabricate lithographic SHINER substrates which report an enhancement factor of 7.5 × 103 ± 17% for our gold nanodot substrates coated with a 2.8 nm aluminium oxide shell. Lastly, by introducing a gold etchant solution to our fabricated SHINER substrate, we verified that the shells fabricated with ALD are truly pin-hole-free.

Alanine Formation in a Zero-Gap Flow Cell and the Role of TiO2/Ti Electrocatalysts.

The electrochemical synthesis of α ${\alpha }$ -amino acids at room temperature and pressure is a sustainable alternative to conventional methods like microbial fermentation and Strecker synthesis. A custom-built zero-gap flow electrolyzer was used to study the electrosynthesis of alanine via the electrocatalytic reductive amination (ERA) of the corresponding biomass-derivable α ${\alpha }$ -keto acid precursor - pyruvic acid (PA), and hydroxylamine (NH2OH) at very low pH. Non-toxic, abundant, and easy to prepare TiO2/Ti electrocatalysts were utilized as the cathode. Three TiO2/Ti felt electrodes with different oxide thicknesses were prepared and their characterization results were correlated with their respective electrochemical performance in terms of Faradaic efficiency η ${\eta }$ , and partial current density j ‾ ${\left|\overline{j}\right|}$ . Cyclic voltammetry indicated a different electrocatalytic reduction process on hydrothermally treated electrodes, compared to thermally oxidized ones. Hydrothermally treated electrodes were also found to have the thickest porous anatase layer and achieved 50-75 % alanine conversion efficiencies. Optimization showed that the cell potential, reactant flow rate and the PA: NH2OH ratio were crucial parameters in determining the conversion efficiency. η ${\eta }$ and j ‾ ${\left|\overline{j}\right|}$ were found to significantly decrease when an excess of is used and, an optimal alanine η ${\eta }$ of 75 % was achieved at 2.0 V applied cell potential and 10 mL/h reactant flow rate.

Workplace interventions focusing on how to plan, organize and design the work environment in hospital settings: A systematic review.

BACKGROUND: Occupational Health Service (OHS) is a service that should support employers and employees with their work environment. Previous research indicates the need for deeper knowledge about the effect of workplace interventions with a focus on planning, organizing and designing the workplace to improve work conditions in hospital settings. OBJECTIVE: The aim was to evaluate the outcomes, workplace interventions and intervention strategies in hospital settings. METHODS: A systematic literature review was conducted. CINAHL, MEDLINE, PsycInfo, Scopus, and Web of Science Core Collection were searched in September 2021. The Mixed Methods Appraisal Tool was used to evaluate the quality of the included studies. Study results are presented through a narrative synthesis. A protocol for this study was registered on the Open Science Framework. RESULTS: Twenty-six studies, published between 2010 and 2021, were included. These included randomized controlled trials (RCTs), non-RCTs, and mixed methods reports with moderate to good quality. The results support the use of workplace interventions to improve work conditions, health, and well-being in hospital settings. Combinations of different interventions, tailored to the specific organization, were used. Important intervention strategies commonly used in the start-up, evaluation, and intervention of successful workplace interventions, were identified. Using a pragmatist complexity approach in workplace interventions can improve outcomes by providing clear intervention strategies and combinations of tailored interventions, related to context specific problems. CONCLUSION: OHS support in workplace interventions with clear intervention strategies will contribute to improve work conditions, health and well-being in hospital settings.

Low-Variance Surface-Enhanced Raman Spectroscopy Using Confined Gold Nanoparticles over Silicon Nanocones.

Surface-enhanced Raman spectroscopy (SERS) substrates are of utmost interest in the analyte detection of biological and chemical diagnostics. This is primarily due to the ability of SERS to sensitively measure analytes present in localized hot spots of the SERS nanostructures. In this work, we present the formation of 67 ± 6 nm diameter gold nanoparticles supported by vertically aligned shell-insulated silicon nanocones for ultralow variance SERS. The nanoparticles are obtained through discrete rotation glancing angle deposition of gold in an e-beam evaporating system. The morphology is assessed through focused ion beam tomography, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. The optical properties are discussed and evaluated through reflectance measurements and finite-difference time-domain simulations. Lastly, the SERS activity is measured by benzenethiol functionalization and subsequent Raman spectroscopy in the surface scanning mode. We report a homogeneous analytical enhancement factor of 2.2 ± 0.1 × 107 (99% confidence interval for N = 400 grid spots) and made a comparison to other lithographically derived assemblies used in SERS. The strikingly low variance (4%) of our substrates facilitates its use for many potential SERS applications.

Large Dense Periodic Arrays of Vertically Aligned Sharp Silicon Nanocones.

Convex cylindrical silicon nanostructures, also referred to as silicon nanocones, find their value in many applications ranging from photovoltaics to nanofluidics, nanophotonics, and nanoelectronic applications. To fabricate silicon nanocones, both bottom-up and top-down methods can be used. The top-down method presented in this work relies on pre-shaping of silicon nanowires by ion beam etching followed by self-limited thermal oxidation. The combination of pre-shaping and oxidation obtains high-density, high aspect ratio, periodic, and vertically aligned sharp single-crystalline silicon nanocones at the wafer-scale. The homogeneity of the presented nanocones is unprecedented and may give rise to applications where numerical modeling and experiments are combined without assumptions about morphology of the nanocone. The silicon nanocones are organized in a square periodic lattice, with 250 nm pitch giving arrays containing 1.6 billion structures per square centimeter. The nanocone arrays were several mm2 in size and located centimeters apart across a 100-mm-diameter single-crystalline silicon (100) substrate. For single nanocones, tip radii of curvature < 3 nm were measured. The silicon nanocones were vertically aligned, baring a height variation of < 5 nm (< 1%) for seven adjacent nanocones, whereas the height inhomogeneity is < 80 nm (< 16%) across the full wafer scale. The height inhomogeneity can be explained by inhomogeneity present in the radii of the initial columnar polymer mask. The presented method might also be applicable to silicon micro- and nanowires derived through other top-down or bottom-up methods because of the combination of ion beam etching pre-shaping and thermal oxidation sharpening. A novel method is presented where argon ion beam etching and thermal oxidation sharpening are combined to tailor a high-density single-crystalline silicon nanowire array into a vertically aligned single-crystalline silicon nanocones array with < 3 nm apex radius of curvature tips, at the wafer scale.

Further psychometric evaluation of the Structured Multidisciplinary Work Evaluation Tool (SMET) questionnaire: Practical implications in healthcare settings.

BACKGROUND: Scientific research has identified a lack of psychometrically well-tested methods for evaluation of the work environment in healthcare settings. The Structured Multidisciplinary Work Evaluation Tool (SMET) questionnaire has been evaluated and has shown good content validity, as well as intra-rater and test-retest reliability. There are, however, still unknowns regarding the psychometric properties. If the SMET questionnaire is to be used in practical occupational health service (OHS) work and scientific research in healthcare settings, further psychometric evaluation is needed. OBJECTIVE: The aim of this study was to gain further understanding of the psychometric properties of the SMET questionnaire when used in research and clinical OHS practice in healthcare settings. METHODS: The psychometric evaluation was conducted using classical test theory (Cronbach's alpha, explorative factor analysis) and Rasch analysis (measurement targeting, category threshold order, person separation index) on data previously collected in development projects within the healthcare sector. RESULTS: The results support the use of the SMET questionnaire as a psychometrically well-tested method for evaluation of the work environment in healthcare settings. They support the use of the initial 1-10 scale since all 10 steps are used. The results also support the trichotomization procedure since the trichotomized scale captures the construct of the work environment with good measurement targeting and good category threshold order. CONCLUSION: The results of this study support the use of the SMET questionnaire as a psychometrically well-tested method for a broad multifactorial evaluation of the work environment in healthcare settings.

Evaluating the Effect of Supported Systematic Work Environment Management During the COVID-19 Pandemic: Protocol for a Mixed Methods Study.

BACKGROUND: The work environment is a complex phenomenon in which many factors interact. Scientific research indicates a relation between the work environment and employee health, staff turnover, patient satisfaction, and patient safety. There is a great need for knowledge on how to conduct work environment interventions and practical work environment management to maximize benefits to the employees. OBJECTIVE: The aim of this study is to explore how Occupational Health Service (OHS) support will affect the work environment, sick leave, staff turnover, patient satisfaction, and patient safety during and following the COVID-19 pandemic in a medical ward setting. METHODS: A mixed methods evaluation of a concurrent work environment quality improvement project at the Department of Internal Medicine and Geriatrics in a local hospital in the south of Sweden will be performed. RESULTS: The mixed methods evaluation of the quality improvement project received funding from Futurum-Academy for Health and Care, Jönköping County Council and Region Jönköping County, and the study protocol was approved by the Swedish Ethical Review Authority. The work environment quality improvement project will continue between May 2020 and December 2021. CONCLUSIONS: The study might contribute to increased knowledge of how work environment interventions and practical work environment management can impact the work environment, and employee health, staff turnover, patient satisfaction, and patient safety. There is a need for knowledge in this area for OHS management to provide increased benefits to employees, employers, and society as a whole. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/34152.

Health surveillance under adverse ergonomics conditions--validity of a screening method adapted for the occupational health service.

A new health surveillance protocol for work-related upper-extremity musculoskeletal disorders has been validated by comparing the results with a reference protocol. The studied protocol, Health Surveillance in Adverse Ergonomics Conditions (HECO), is a new version of the reference protocol modified for application in the Occupational Health Service (OHS). The HECO protocol contains both a screening part and a diagnosing part. Sixty-three employees were examined. The screening in HECO did not miss any diagnosis found when using the reference protocol, but in comparison to the reference protocol considerable time savings could be achieved. Fair to good agreement between the protocols was obtained for one or more diagnoses in neck/shoulders (86%, k = 0.62) and elbow/hands (84%, k = 0.49). Therefore, the results obtained using the HECO protocol can be compared with a reference material collected with the reference protocol, and thus provide information of the magnitude of disorders in an examined work group. Practitioner Summary: The HECO protocol is a relatively simple physical examination protocol for identification of musculoskeletal disorders in the neck and upper extremities. The protocol is a reliable and cost-effective tool for the OHS to use for occupational health surveillance in order to detect workplaces at high risk for developing musculoskeletal disorders.

Relation between perceived and measured workload obtained by long-term inclinometry among dentists.

Dentists reported high perceived physical work conditions. Working postures and movements of the head and upper extremities during dental work were registered with inclinometry measurements during four hours. The aim was to clarify the relationship between measured working postures/movements and perceived physical work conditions. Dentists worked with elevated arms and a rather steep forward inclination of the head. Correlations (r=-0.52 to -0.66) between inclination velocity and perceived workload on VAS scales were found, but there were only weak correlations between observed working postures. The different tasks involved in dental work provide limited variation in work movements and postures, measured by inclinometry. By alternating between sitting and standing, it might be possible to achieve variation in physical workload during dental work.

Relationships between psychosocial work environmental factors, personality, physical work demands and workload in a group of Swedish dentists.

The aim of the study was to investigate, in a group of 77 Swedish dentists (36 males, 41 females) working in dental clinics, possible effects of psychosocial work environmental factors, personality traits, and social desirability tendencies on their reporting of their workload and of the physical demands placed on them. Participants were given questionnaires for assessing their workload, the physical and psychosocial demands of their job, their social support at work, and their control over their work situation, using a 10-cm visual analogue scale (V.A.S.). The Eysenck Personality Questionnaire (EPQ) was also given to assess neuroticism and extraversion and the Marlowe-Crown SD-scale to measure tendencies to answer questions in a socially desirable manner. As in two earlier studies of ours, very high assessments were made of workload, physical work demands and social support. Higher assessments of workload and of physical work demands were found in those assessing the psychosocial work demands placed on them to be higher. Those assessing the work load of their job as higher also considered themselves to have less control over their work situation and were less extraverted. Despite these dentists perceiving themselves as being faced with a stressful work situation involving a high workload, strong physical and psychosocial demands being placed on them and their having a low degree of control over their work situation, the high degree of social support they experienced may have made their work situation less stressful.

Perceived contra observed physical work load in Swedish dentists.

In an earlier questionnaire study, dentists reported high experienced physical work load in their profession, but low to moderate complaints from their musculoskeletal system. The correlation between reported physical work load and pain from the musculoskeletal system was weak. This discrepancy could not be satisfactorily explained. Therefore, a second study was undertaken, in which the same 27 dentists who reported musculoskeletal problems were video recorded during one hour of clinical work, and the records were later analyzed using PEO (Portable Ergonomic Observation). PEO is a frequency analysis method which allows observation of work in real time using a portable computer or video recordings. PEO can be adjusted for registration of single or multiple work operations. Output data are presented as frequency, duration, and sequence of the various work operations. The aim of the present study was to investigate if there was a relation between observed work load recorded with PEO, and subjectively estimated work load and musculoskeletal complaints recorded with a questionnaire based on Visual Analogue Scales. Sitting and standing postures, and head, trunk and arm movements were analyzed. The PEO observations showed that dentists generally perform their clinical work in a sitting position, with the head bent forward almost half of the time. Only weak to moderate correlations (r =0.0-0.6) were found between observed physical work load and subjective estimations of experienced physical work load and musculoskeletal complaints. These findings support the results in our previous study, but they do not explain the large difference between the observed low work load and the subjectively experienced high work load. The study will be followed up by EMG measurements and free interviews, where both muscular load and psychosocial factors will be evaluated.

Evaluation of muscular activity, local muscular fatigue, and muscular rest patterns among dentists.

In a previous study, dentists reported very high scores for perceived physical workload, but only low to moderate scores for the musculoskeletal system. This is difficult to explain when other occupational groups in the dental services are compared, and is the main reason why the present study was performed. To measure muscular activity, a surface electromyography (sEMG) study was done, and included the subjects who reported neck and shoulder complaints in the previous study. A portable sEMG system (MyoGuard) was used to collect a myoelectric signal on-line and analysis of the myoelectric signal in a computer. sEMG was recorded from both trapezius muscles for approximately 4 h during an ordinary working day. Twenty-seven dentists participated in the study. The results show accumulated rest% fairly close to that of female cashiers and supermarket employees and increased average rectified value percent (ARV%) during work that could contribute to the very high workload perceived by dentists.