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Objective. To test, in this pilot study, whether DHEA-S (Dehydroepiandrosterone, sulfated form) plasma levels are lower among persons with chronic neck pain, compared to control persons, and to investigate the DHEA-S response after a physical exercise. Subjects. Included were 12 persons with chronic neck pain and eight controls without present pain, all 18 and 65 years of age. Exclusion criteria for both groups were articular diseases or tendinosis, fibromyalgia, systemic inflammatory and neuromuscular diseases, pain conditions due to trauma, or severe psychiatric diseases. Design and methods. The participants arm-cycled on an ergometer for 30 minutes. Blood samples were taken before, 60 minutes, and 150minutes after this standardized physical exercise. Results. The estimated plasma DHEA-S levels at baseline were 2.0 µmol/L (95% confidence interval [CI] 1.00; 4.01) in the pain group and 4.1 mmol/L (95% CI2.0; 8.6) in the control group, adjusted for sex, age, body mass index (BMI), and Shirom-Melamed Burnout Questionnaire (SMBQ), with a ratio of 0.48 (P = 0.094). The total DHEA-S (AUCG) in the pain group were 183min*µmol/L lower than in the control group (P = 0.068). For the response to the exercise (AUCl), the difference between the pain group and the control group was 148min*µmol/L (P = 0.011). Conclusions. In this pilot study, the plasma DHEA-S levels appeared to be lower among the persons with chronic neck pain, compared with the control group. It was indicated that DHEA-S decreased during the physical exercise in the control group, and either increased or was unaffected in the chronic pain group. [ABSTRACT FROM AUTHOR]

Background and Aims: Mixed forest plantations are increasingly recognised for their role in mitigating the impacts of climate change and enhancing ecosystem resilience. Yet, there remains a significant gap in understanding the early-stage dynamics of species trait diversity and interspecies interactions, particularly in pure deciduous mixtures. This study aims to explore the timing and mechanisms by which trait diversity of deciduous species and competitive interactions influence yield, carbon allocation, and space occupation in mixed forests, both above- and belowground., Methods: A forest inventory was conducted in planted monocultures, 2-species, and 4-species mixtures of European Acer, Tilia, Carpinus, and Quercus, representing a spectrum from acquisitive to conservative tree species. Competition effects were assessed with linear mixed-effects models at the level of biomass and space acquisition, including leaf, canopy, stem, and fine root traits., Key Results: Early aboveground growth effects were observed six years post-planting, with significant biomass accumulation after eight years, strongly influenced by species composition. Mixtures, especially with acquisitive species, exhibited aboveground overyielding, 1.5- to 1.9-times higher than monocultures. Fine roots showed substantial overyielding in high diversity stands. Biomass allocation was species-specific and varied markedly by tree size, the level of diversity, and between acquisitive Acer and the more conservative species. No root segregation was found., Conclusions: Our findings underscore the critical role of species trait diversity in enhancing productivity in mixed deciduous forest plantations. Allometric changes highlight the need to differentiate between (active) acclimations and (passive) tree size-related changes, but illustrate major consequences of competitive interactions for the functional relation between leaves, stem, and roots. This study points towards the significant contributions of both above- and belowground components to overall productivity of planted mixed-species forests., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Annals of Botany Company.)

Increasing tree diversity is considered a key management option to adapt forests to climate change. However, the effect of species diversity on a forest's ability to cope with extreme drought remains elusive. In this study, we assessed drought tolerance (xylem vulnerability to cavitation) and water stress (water potential), and combined them into a metric of drought-mortality risk (hydraulic safety margin) during extreme 2021 or 2022 summer droughts in five European tree diversity experiments encompassing different biomes. Overall, we found that drought-mortality risk was primarily driven by species identity (56.7% of the total variability), while tree diversity had a much lower effect (8% of the total variability). This result remained valid at the local scale (i.e within experiment) and across the studied European biomes. Tree diversity effect on drought-mortality risk was mediated by changes in water stress intensity, not by changes in xylem vulnerability to cavitation. Significant diversity effects were observed in all experiments, but those effects often varied from positive to negative across mixtures for a given species. Indeed, we found that the composition of the mixtures (i.e., the identities of the species mixed), but not the species richness of the mixture per se, is a driver of tree drought-mortality risk. This calls for a better understanding of the underlying mechanisms before tree diversity can be considered an operational adaption tool to extreme drought. Forest diversification should be considered jointly with management strategies focussed on favouring drought-tolerant species., (© 2024 John Wiley & Sons Ltd.)

Decades of studies have demonstrated links between biodiversity and ecosystem functioning, yet the generality of the relationships and the underlying mechanisms remain unclear, especially for forest ecosystems. Using 11 tree-diversity experiments, we tested tree species richness-community productivity relationships and the role of arbuscular (AM) or ectomycorrhizal (ECM) fungal-associated tree species in these relationships. Tree species richness had a positive effect on community productivity across experiments, modified by the diversity of tree mycorrhizal associations. In communities with both AM and ECM trees, species richness showed positive effects on community productivity, which could have resulted from complementarity between AM and ECM trees. Moreover, both AM and ECM trees were more productive in mixed communities with both AM and ECM trees than in communities assembled by their own mycorrhizal type of trees. In communities containing only ECM trees, species richness had a significant positive effect on productivity, whereas species richness did not show any significant effects on productivity in communities containing only AM trees. Our study provides novel explanations for variations in diversity-productivity relationships by suggesting that tree-mycorrhiza interactions can shape productivity in mixed-species forest ecosystems., (© 2024 The Authors. New Phytologist © 2024 New Phytologist Foundation.)

Drawing on collective experience from ten collaborative research projects focused on the Global South, we identify three major challenges that impede the translation of research on sustainability and resilience into better-informed choices by individuals and policy-makers that in turn can support transformation to a sustainable future. The three challenges comprise: (i) converting knowledge produced during research projects into successful knowledge application; (ii) scaling up knowledge in time when research projects are short-term and potential impacts are long-term; and (iii) scaling up knowledge across space, from local research sites to larger-scale or even global impact. Some potential pathways for funding agencies to overcome these challenges include providing targeted prolonged funding for dissemination and outreach, and facilitating collaboration and coordination across different sites, research teams, and partner organizations. By systematically documenting these challenges, we hope to pave the way for further innovations in the research cycle., (© 2024. The Author(s).)

Plant diversity effects on community productivity often increase over time. Whether the strengthening of diversity effects is caused by temporal shifts in species-level overyielding (i.e., higher species-level productivity in diverse communities compared with monocultures) remains unclear. Here, using data from 65 grassland and forest biodiversity experiments, we show that the temporal strength of diversity effects at the community scale is underpinned by temporal changes in the species that yield. These temporal trends of species-level overyielding are shaped by plant ecological strategies, which can be quantitatively delimited by functional traits. In grasslands, the temporal strengthening of biodiversity effects on community productivity was associated with increasing biomass overyielding of resource-conservative species increasing over time, and with overyielding of species characterized by fast resource acquisition either decreasing or increasing. In forests, temporal trends in species overyielding differ when considering above- versus belowground resource acquisition strategies. Overyielding in stem growth decreased for species with high light capture capacity but increased for those with high soil resource acquisition capacity. Our results imply that a diversity of species with different, and potentially complementary, ecological strategies is beneficial for maintaining community productivity over time in both grassland and forest ecosystems., (© 2024. The Author(s).)

Lingering breathing difficulties are common after COVID-19. However, the underlying causes remains unclear, with spirometry often being normal. We hypothesized that small airway dysfunction (SAD) can partly explain these symptoms. We examined 48 individuals (32 women, 4 hospitalized in the acute phase) who experienced dyspnea and/or cough in the acute phase and/or aftermath of COVID-19, and 22 non-COVID-19 controls. Time since acute infection was, median (range), 65 (10-131) weeks. We assessed SAD using multiple breath washout (MBW) and impulse oscillometry (IOS) and included spirometry and diffusing-capacity test (DLCO). One-minute-sit-to-stand test estimated physical function, and breathing difficulties were defined as answering "yes" to the question "do you experience lingering breathing difficulties?" Spirometry, DLCO, and IOS were normal in almost all cases (spirometry: 90%, DLCO: 98%, IOS: 88%), while MBW identified ventilation inhomogeneity in 50%. Breathing difficulties (n = 21) was associated with increased MBW-derived S acin . However, physical function did not correlate with SAD. Among individuals with breathing difficulties, 25% had reduced physical function, 25% had SAD, 35% had both, and 15% had normal lung function and physical function. Despite spirometry and DLCO being normal in almost all post-COVID-19 individuals, SAD was present in a high proportion and was associated with lingering breathing difficulties., (© 2024 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Background: Radiation-induced fecal urgency syndrome is highly prevalent in gynecological cancer survivors. It is associated with decreased quality of life (QoL) and with disability pension. The literature remains unclear about the mediating role of physical and psychological aspects of QoL in the association between urgency syndrome and disability pension. Identifying the pathways between urgency syndrome and disability pension may help to create effective and timely interventions for increasing QoL and reducing disability pension among gynecological cancer survivors., Methods: We used patient-reported outcome measures from working-age gynecological cancer survivors (n = 247) and data on their disability pension from the official register. The mediating role of physical and psychological aspects of QoL was studied by utilizing mediation analysis based on the counterfactual framework, appropriate for binary outcome, binary mediator with an exposure-mediator interaction. The total effect (TE) was divided into direct and indirect effects using single mediation analysis. Adjusted relative risks and percentage mediated (95% confidence intervals) were calculated. All statistical tests were two-sided., Results: Urgency syndrome increased the risk of disability pension both directly and indirectly (via QoL). Satisfaction with sleep mediated half of the TE (RR = 2.2 (1.1-4.1)) of urgency syndrome on disability pension. Physical health also mediated a similar proportion of the TE (RR = 2.1 (1.2-3.9)). The proportions mediated were higher for physical aspects of QoL (35%-71%) than for psychological aspects (2%-47%)., Conclusions: The investigated aspects of the self-assessed QoL of gynecological cancer survivors may play a role in these women's continuing work-life. It appears that physical health, satisfaction with sleep, psychological well-being, and other investigated aspects of QoL mediate the urgency syndrome-disability pension association., (© 2023 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Ectomycorrhizal (ECM) fungi can both accelerate and decelerate decomposition of organic matter in forest soils, but a mechanistic understanding of this differential influence is limited. Here, we tested how ECM fungi affect decomposition along a natural fertility gradient in a temperate forest of European beech. Trees were girdled to reduce belowground carbon supply to the soil. Girdling shifted soil fungal community composition and decreased hyphal biomass production and soil CO 2 efflux, indicating a reduced ECM fungal activity. Girdling also affected decomposition processes, but the effects depended on fertility. Our results indicate that ECM fungi decelerate decomposition under conditions of low fertility while under conditions of high fertility ECM fungi and their host roots have an accelerating effect. We conclude that both acceleration and deceleration of decomposition of organic matter by ECM fungi can occur within a forest, with soil fertility determining the direction and magnitude of these effects. We suggest a positive feedback between fertility, stand productivity and soil carbon and nitrogen dynamics that is mediated to a large extent by ECM fungi., (© 2023 The Authors. New Phytologist © 2023 New Phytologist Foundation.)

Background: Long COVID is defined by the persistence of physical and/or psychological and cognitive symptoms debuting after SARS-CoV-2 infection. Individuals affected describe impairing and debilitating symptoms sometimes making it difficult to take part in work and social life. Long COVID is likely to have an impact on the work force., Objective: The aim of the study was to explore workplace factors that promote and hinder work ability and return to work among individuals with long-term effects of COVID-19., Methods: A qualitative design was used. Data were collected by semi-structured focus group interviews and analysed using inductive thematic analysis. To increase trustworthiness, several researchers were involved in the data collection and analysis. Five focus group interviews were conducted with individuals suffering from long-term effects from COVID-19 affecting their work ability. In total, 19 individuals participated in the study, and all were working at least 50 per cent at the time of recruitment., Results: Five main themes emerged from the analysis: Communication and support, Possibilities to adjust work, Acceptance of new limitations, Increased need for recovery from work and Lack of knowledge and understanding of the effects of Covid., Conclusion: The results suggested that it is useful to facilitate communication, support and work adjustments for individuals suffering from Long COVID. It is also important to accept limitations and fluctuations in work ability and encourage recovery during and after work.

Vegetable grafting is increasingly recognized as an effective and sustainable plant production alternative. Grafted plants usually show increased uptake of water and minerals compared with self-rooted plants, mostly thought a consequence of the vigorous rootstocks selected. However, while studies frequently addressed the effects of rootstocks on the performance of scions, knowledge on the influences of scions on biomass allocation, morphology, and metabolic activity of roots is rare. In particular, the plasticity of root traits affecting resource acquisition and its efficiency remains poorly understood. Two different rootstock species, Cucurbita maxima × Cucurbita moschata and Lagenaria siceraria , were grafted in combination with melon ( Cucumis melo ) and watermelon ( Citrullus lanatus ). Self-grafted rootstocks were used as control. Plant biomass and root traits were determined after destructive harvesting 30 and/or 60 days after grafting. Traits included biomass allocation, leaf and root morphology, potential activities of four extracellular enzymes on root tips and basal root segments, and root respiration. Successfully grafted scions increase the ratio of root to whole plant dry matter (RMF), and increased ratios of root length to whole plant dry matter (RLR) and to plant leaf area (RL : LA). In contrast, morphological root traits such as diameter, tissue density, and specific root length remain surprisingly stable, and thus scion-induced changes of those traits may only play a minor role for the beneficial effects of grafting in Cucurbitaceae. Incompatibility in melon/ L. siceraria grafts, however, was likely responsible for the reduced root growth in combination with clear changes in root morphological traits. Reduced root respiration rates seem to be the effects of a non-compatible rootstock-scion combination rather than an active, C-efficiency increasing acclimation. In contrast, heterografts with melon and watermelon frequently resulted in root-stock-specific, often enhanced potential enzymatic activities of acid phosphatase, β -glucosidase, leucine-amino-peptidase, and N-acetyl-glucosaminidase both at root tips and basal parts of lateral roots-presenting a potential and complementary mechanism of grafted plants to enhance nutrient foraging. The studied melon and watermelon scions may thus increase the nutrient foraging capacity of grafted plants by fostering the relative allocation of C to the root system, and enhancing the extracellular enzymatic activities governed by roots or their rhizobiome., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sallaku, Rewald, Sandén and Balliu.)

Purpose: Gynaecological cancer patients treated with external radiation therapy to the pelvis may face long-lasting and long-term gastrointestinal syndromes. The aim of this study was to assess the association between such radiation-induced survivorship syndromes and disability pension among gynaecological cancer survivors treated with pelvic radiation therapy., Methods: This prospective register study included gynaecological cancer survivors (n=247) treated during 1991-2003, alive at the time of the study, and <65 years of age. In 2006, they completed a postal questionnaire measuring patient-reported outcomes. The self-reported data were linked to the national register on disability pensions. Relative risks and risk differences with 95% confidence intervals (CIs) of being granted a disability pension were estimated using log-binomial regression., Results: Gynaecological cancer survivors with gastrointestinal syndromes had a higher risk of disability pension than survivors without such syndromes. Survivors with blood discharge syndrome had a 2.0 (95% CI 1.3-3.2) times higher risk of disability pension than survivors without blood discharge syndrome. The relative risk among survivors with urgency syndrome was 1.9 (1.3-2.9) and for leakage syndrome, 2.1 (1.4-3.1). Adjusting for age did not affect our interpretation of the results., Conclusions: Gynaecological cancer survivors with a specific radiation-induced survivorship syndrome have a higher risk of disability pension than survivors without that specific syndrome., Implications for Cancer Survivors: The findings highlight the need for more awareness and knowledge regarding the potential role of radiation-induced survivorship syndromes for continuing work among gynaecological cancer survivors. Work-life-related parameters should be considered during radiotherapy and rehabilitation after treatment., (© 2021. The Author(s).)

Volatile organic compounds (VOCs) emitted by plants consist of a broad range of gasses which serve purposes such as protecting against herbivores, communicating with insects and neighboring plants, or increasing the tolerance to environmental stresses. Evidence is accumulating that the composition of VOC blends plays an important role in fulfilling these purposes. Constitutional emissions give insight into species-specific stress tolerance potentials and are an important first step in linking metabolism and function of co-occurring VOCs. Here, we investigate the blend composition and interrelations among co-emitted VOCs in unstressed seedlings of four broad-leaved tree species, Quercus robur, Fagus sylvatica, Betula pendula , and Carpinus betulus . VOCs of Q. robur and F. sylvatica mainly emitted isoprene and monoterpenes, respectively. B. pendula had relatively high sesquiterpene emission; however, it made up only 1.7% of its total emissions while the VOC spectrum was dominated by methanol (∼72%). C. betulus was emitting methanol and monoterpenes in similar amounts compared to other species, casting doubt on its frequent classification as a close-to-zero VOC emitter. Beside these major VOCs, a total of 22 VOCs could be identified, with emission rates and blend compositions varying drastically between species. A principal component analysis among species revealed co-release of multiple compounds. In particular, new links between pathways and catabolites were indicated, e.g., correlated emission rates of methanol, sesquiterpenes (mevalonate pathway), and green leaf volatiles (hexanal, hexenyl acetate, and hexenal; lipoxygenase pathway). Furthermore, acetone emissions correlated with eugenol from the Shikimate pathway, a relationship that has not been described before. Our results thus indicate that certain VOC emissions are highly interrelated, pointing toward the importance to improve our understanding of VOC blends rather than targeting dominant VOCs only., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Fitzky, Peron, Kaser, Karl, Graus, Tholen, Pesendorfer, Mahmoud, Sandén and Rewald.)

Fungi are known to exert a significant influence over soil organic matter (SOM) turnover, however understanding of the effects of fungal community structure on SOM dynamics and its consequences for ecosystem fertility is fragmentary. Here we studied soil fungal guilds and SOM decomposition processes along a fertility gradient in a temperate mountain beech forest. High-throughput sequencing was used to investigate fungal communities. Carbon and nitrogen stocks, enzymatic activity and microbial respiration were measured. While ectomycorrhizal fungal abundance was not related to fertility, saprotrophic ascomycetes showed higher relative abundances under more fertile conditions. The activity of oxidising enzymes and respiration rates in mineral soil were related positively to fertility and saprotrophic fungi. In addition, organic layer carbon and nitrogen stocks were lower on the more fertile plots, although tree biomass and litter input were higher. Together, the results indicated a faster SOM turnover at the fertile end of the gradient. We suggest that there is a positive feedback mechanism between SOM turnover and fertility that is mediated by soil fungi to a significant extent. By underlining the importance of fungi for soil fertility and plant growth, these findings furthermore emphasise the dependency of carbon cycling on fungal communities below ground., (© 2021 The Authors New Phytologist © 2021 New Phytologist Foundation.)

Forests on steep slopes constitute a significant proportion of European mountain areas and are important as production and protection forests. This study describes the soil fungal community structure in a European beech-dominated mountain forest stands in the Northern Calcareous Alps and investigates how it is determined by season and soil properties. Samples were collected at high spatial resolution in an area of ca. 100 m × 700 m in May (spring) and August (summer). Illumina MiSeq high-throughput sequencing of the ITS2-region revealed distinct patterns for the soil fungal communities. In contrast to other studies from temperate European beech forest stands, Ascomycota dominated the highly diverse fungal community, while ectomycorrhizal fungi were of lower abundance. Russulaceae, which are often among the dominant ectomycorrhizal fungi associated with European beech, were absent from all samples. Potentially plant pathogenic fungi were more prevalent than previously reported. Only subtle seasonal differences were found between fungal communities in spring and summer. Especially, dominant saprotrophic taxa were largely unaffected by season, while slightly stronger effects were observed for ectomycorrhizal fungi. Soil characteristics like pH and organic carbon content, on the other hand, strongly shaped abundant taxa among the saprotrophic fungal community., (© 2021. The Author(s).)

We evaluated whether changes in fine root non-structural carbohydrate reserves of Fagus sylvatica and Pinus sylvestris trees influence potential enzymatic activities of their ectomycorrhizal symbionts from winter towards spring reactivation, and whether these changes influence potential soil enzymatic activities. We analyzed sugar and starch concentrations in the fine roots of Fagus sylvatica and Pinus sylvestris and potential activities of ß-glucosidase, ß-xylosidase, and cellobiohydrolase (as proxies for carbon-degrading enzymes) as well as leucine aminopeptidase and chitinase (as proxies for nitrogen-degrading enzymes) of their dominant ectomycorrhizal symbionts as well as in the soil. Sugar concentrations in the fine roots were significantly positively correlated with enzymatic activities of the ectomycorrhizal symbionts. In Pinus sylvestris, both carbon- and nitrogen-degrading enzyme activities showed significant positive correlations with fine root sugar concentrations. In Fagus sylvatica, fine root sugar concentrations were explicitly positively correlated with the activity of nitrogen-degrading enzymes. The chitinase activity in the soil was found to be strongly positively correlated with the enzymatic activity of the ectomycorrhizal symbionts as well as with fine root sugar concentrations. Fine root carbohydrate concentrations of Fagus sylvatica and Pinus sylvestris trees and enzymatic activities of their associated ectomycorrhizal fungi are connected. The specific nutrient demand of the tree species during spring reactivation may affect ectomycorrhizal enzymatic activity via carbon mobilization in the fine roots of Fagus sylvatica and Pinus sylvestris. Moreover, our results suggest that trees indirectly contribute to the degradation of fungal necromass by stimulating ectomycorrhizal chitinase activity in the soil.

Background: The aim of this study was to investigate what exposure to work demands, physical and psychosocial, is associated with lower levels of sickness absence among workers with neck or upper back pain in different groups, by age, gender, duration of sickness absence and work ability score., Methods: This study was a prospective study of 4567 workers with neck or upper back pain. Data on neck or upper back pain, work demand and work ability were obtained from the Swedish Work Environment survey over a 3-year period (2009-2013). Register data on sickness absence, 1 year after each survey was conducted, were obtained from the Swedish health insurance database. Analyses were performed to estimate the association between self-reported work demands and registered sick days > 14 days. The analyses were stratified for gender, age group and work ability score., Results: Lower numbers of sick days were found for workers reporting low exposure to lifting ≥15 kg and twisted or forward-leaning work postures. Lower numbers of sick days were found for workers reporting high work control and seated work. The associations were generally stronger in the older age groups for the physical work demands., Conclusions: The findings in this study suggest that certain physical work demands and having high control over one's work can result in lower sickness absence, especially among middle-aged and older workers with neck or upper back pain.

Objective: The objective of this study was to investigate whether workplace interventions are effective in reducing sickness absence in persons with work-related neck and upper extremity disorders and whether disorder improvement after intervention reduces sickness absence., Methods: This study was a prospective cohort study of workers with work-related neck pain or upper extremity disorders. Data were obtained from the Swedish "Work-related disorders" and "Work environment" surveys. Register data on sickness-absence 1 year after the surveys were made and obtained from the Swedish health insurance database., Results: A significant lower number of sickness-absence days were found for workers reporting improvement after intervention., Conclusion: The findings in this study suggest that workplace intervention can reduce sickness absence for workers with neck or upper extremity disorders only if the intervention improves the disorder. The interventions were most effective in reducing medium long sickness absence periods.

The development of musculoskeletal disorders has been linked to various risk factors in the work environment including lifting heavy loads, machine and materials handling, work postures, repetitive work, work with handheld vibrating tools, and work stress. The Quick Exposure Check (QEC) was designed to assess exposure to work-related musculoskeletal risk factors affecting the back, shoulder/arm, wrist/hand, and neck. We investigated the inter-rater reliability of the summary scores and individual items of the QEC by comparing two simultaneous assessments of 51 work tasks, performed by 14 different workers. The work tasks were mainly "light" to "moderately heavy". For total scores, the level of disagreement for shoulder/arm had a Relative Position of 0.13 (95% CI: 0.02; 0.23) and no statistically significant random disagreement. Percentage agreement was 63-100% for individual items and 71-88% for total score. Weighted Kappa of agreement for the individual items rated by the assessors were -0.94-0.77; highest for back motion, and lowest for wrist/hand position. The Swedish translation of the Quick Exposure Check has moderate to very good inter-rater reliability with fair to slight levels of systematic disagreement. There was no statistically significant random disagreement., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Land use changes and related land management practices significantly alter soil physicochemical properties; however, their effects on the soil microbial community structure are still unclear. In this study, we used automated ribosomal intergenic spacer analysis to determine the fungal and bacterial community composition in soils from different land use areas in the Ethiopian highlands. Soil samples were collected from five areas with different land uses, natural forest, eucalyptus plantation, exclosure, grassland and cropland, which had all historically been natural forest., Results: Our results showed a significant shift in the soil bacterial and fungal community composition in response to land use change. We also identified soil physicochemical factors corresponding to the changes in bacterial and fungal communities. Although most soil attributes, including soil organic carbon, total soil nitrogen, labile P, soil pH and soil aggregate stability, were related to the change in bacterial community composition, the total soil nitrogen and soil organic carbon had the strongest relationships. The change in fungal community composition was correlated with soil nutrients, organic carbon, soil nitrogen and particularly the labile P concentration., Conclusions: The fungal community composition was likely affected by the alteration of vegetation cover in response to land use change, whereas the bacterial communities were mainly sensitive to changes in soil attributes. The study highlights the higher sensitivity of fungal communities than bacterial communities to land use changes.

Objectives: The aim of the present study was to investigate the possible increase in hand tremor in relation to hand-arm vibration (HAV) exposure in a cohort of exposed and unexposed workers., Methods: Participants were 178 male workers with or without exposure to HAV. The study is cross-sectional regarding the outcome of tremor and has a longitudinal design with respect to exposure. The dose of HAV exposure was collected via questionnaires and measurements at several follow-ups. The CATSYS Tremor Pen(®) was used for measuring postural tremor. Multiple linear regression methods were used to analyze associations between different tremor variables and HAV exposure, along with predictor variables with biological relevance., Results: There were no statistically significant associations between the different tremor variables and cumulative HAV or current exposure. Age was a statistically significant predictor of variation in tremor outcomes for three of the four tremor variables, whereas nicotine use was a statistically significant predictor of either left or right hand or both hands for all four tremor variables., Conclusions: In the present study, there was no evidence of an exposure-response association between HAV exposure and measured postural tremor. Increase in age and nicotine use appeared to be the strongest predictors of tremor.

Prolonged exposure to hand-held vibrating tools may cause a hand-arm vibration syndrome (HAVS), sometimes with individual susceptibility. The neurological symptoms seen in HAVS are similar to symptoms seen in patients with carpal tunnel syndrome (CTS) and there is a strong relationship between CTS and the use of vibrating tools. Vibration exposure to the hand is known to induce demyelination of nerve fibres and to reduce the density of myelinated nerve fibres in the nerve trunks. In view of current knowledge regarding the clinical effects of low nerve-fibre density in patients with neuropathies of varying aetiologies, such as diabetes, and that such a low density may lead to nerve entrapment symptoms, a reduction in myelinated nerve fibres may be a key factor behind the symptoms also seen in patients with HAVS and CTS. Furthermore, a reduced nerve-fibre density may result in a changed afferent signal pattern, resulting in turn in alterations in the brain, further prompting the symptoms seen in patients with HAVS and CTS. We conclude that a low nerve-fibre density lead to symptoms associated with nerve entrapment, such as CTS, in some patients with HAVS.

Objective: The aim of this study was to investigate the exposure-response relationship of hand-arm vibration exposure to neurological symptoms (numbness) of the hand in a cohort of vibration-exposed workers., Methods: The baseline cohort comprised 241 office and manual workers with and without exposure to hand-arm vibration. Numbness (the symptom or event) in the hand was assessed for all subjects at baseline and follow-ups after 5, 10, and 16 years. The workers were stratified into quartiles with no exposure in the first quartile and increasing intensity of exposure in quartiles 2-4 (groups 1-3). Data analysis was performed using survival analysis (time to event). Information on cumulative exposure and years of exposure to event was collected via questionnaires. Measurements were performed in accordance with the International Organization for Standardization (ISO) 5349-1., Results: The hazard ratio (HR) of risk of event (numbness) differed statistically significantly between the non-exposed group (group 0) and the two higher exposure groups (groups 2 and 3). There was also a significant ratio difference between the lowest exposure group (group 1) and the two higher groups. The ratio for group 1 was 1.77 [95% confidence interval (95% CI) 0.96-3.26] compared with 3.78 (95% CI 2.15-6.62) and 5.31 (95% CI 3.06-9.20) for groups 2 and 3, respectively., Conclusion: The results suggest a dose-response relationship between vibration exposure and numbness of the hands. This underlines the importance of keeping vibration levels low to prevent neurological injury to the hands.

In chronic diffuse upper limb pain physical abnormalities are usually absent. The aims of our study were to investigate: (1) the function of somatosensory pathways and (2) the influence of mood on vibration perception. Measurements were made of: (i) vibrotactile perception thresholds (VPTs) and nerve conduction in working women with (n = 35) and without (n = 65) chronic diffuse upper limb pain, and (ii) perceived stress and energy using a two-dimensional mood adjective checklist. The groups did not differ in any nerve conduction measurements. Women with chronic pain had raised VPTs in the radial and ulnar nerve areas, but not in the median nerve area. Neither perceived stress nor energy appeared to influence the VPT. Increases of VPTs in chronic diffuse upper limb pain may be due to peripheral nerve affliction, but our findings support the idea that they may also be secondary to pain and may be related to a central nervous mechanism.

Objectives: A literature report described significantly raised vibration threshold within the territory of the median nerve in a group of office workers and concluded that the results indicated a change in the function of large sensory fibres. The aim of the present cross-sectional study was to compare vibrotactile perception thresholds and nerve conduction measurements in the upper extremity between female computer users (secretaries) and female non-users (nurses)., Methods: Eighty-two secretaries, aged 25-65 (median 44) years and 35 nurses, aged 24-57 (median 46) years went through nerve conduction measurements on the dominant hand and also a vibration threshold test with readings over the hand at five sites which tested cutaneous innervation of the median, ulnar, and radial nerves., Results: There was no significant difference in any parameter of the nerve conduction testing and there was no significant difference in any parameter of the vibration threshold test between secretaries and nurses. The numerical differences between groups were small and in both directions and thus do not indicate a power problem., Conclusions: We saw no signs of early neural deficits of large sensory fibres in subjects who intensively use computer keyboard equipment.

Objective: To achieve optimal diagnostic accuracy, measurements of nerve conduction velocity require standardised tissue temperatures. To warm an extremity to a desired temperature that remains constant during the measurement may be difficult, especially in subjects with low finger temperatures. The aim of this study was to investigate if a submaximal bicycle ergometer test before the examination would be a useful method of obtaining high and stable finger temperatures during nerve conduction studies in the hand., Methods: 114 women aged 25-65 (median 44) performed a bicycle ergometer test on an electrically braked bicycle ergometer (Siemens-Elema) before they underwent a nerve conduction test., Results: Before cycling, the mean finger temperature was 28.1 degrees C (range 20.5-35.4 degrees C) and 15 min after the test 35.1 degrees C (range 30.3-36.9 degrees C). The levels remained almost constant throughout the nerve conduction examination, which had a duration of approximately 25 min., Conclusions: A bicycle ergometer test proved to be a simple and effective method of raising hand temperature.