Distance models in ecological network management: A case study of patch connectivity in a grassland network

Landscape connectivity is a key issue of nature conservation and distance parameters are essential for the calculation of patch level metrics. For such calculations the so-called Euclidean and the least cost distance are the most widespread models. In the present work we tested both distance models for landscape connectivity, using connectivity metrics in the case of a grassland mosaic, and the ground beetle Pterostichus melas as a focal species. Our goal was to explore the dissimilarity between the two distance models and the consequent divergence from the calculated values of patch relevance in connectivity. We found that the two distance models calculated the distances similarly, but their estimations were more reliable over short distances (circa 500 m), than long distances (circa 3000 m). The variability in the importance of habitat patches (i.e. patch connectivity indices) was estimated by the difference between the two distance models (Euclidean vs. least cost) according to the patch size. The location of the habitat patches in the matrix seemed to be a more important factor than the habitat size in the estimation of connectivity. The uncertainty of three patch connectivity indices (Integral Index of Connectivity, Probability of Connectance and Flux) became high above a habitat size of 5 ha. Relevance of patches in maintaining connectivity varied even within small ranges depending on the estimator of distance, revealing the careful consideration of these methods in conservation planning.     

Effect of landscape composition and arrangement on biological control agents in a simplified agricultural system: A cost–distance approach

Landscape simplification has been clearly demonstrated to have negative impacts on the in-crop density and biological-control activity of natural enemies in agricultural landscapes. The role of spatial arrangement of the landscape, however, has not been investigated in agroecosystems. We applied cost–distance modeling to investigate the relationship between the in-crop density of natural enemies and the structural connectivity of non-crop land uses surrounding crops within Australian cotton landscapes. We further compared the explanatory power of this approach with the more commonly used spatially specific proportional-area approach, which considers landscape composition in terms of the proportional area of a given land use within a given radius. Cost–distance metrics offered a more significant explanation of in-crop density for the predatory beetle Dicranolaius bellulus (Coleoptera: Melyridae) than did the proportional-area approach. The in-crop density for this species was positively and significantly correlated with the connectivity of wooded land uses within a 3000 m radius. However, for natural enemy taxa that responded to landscape characteristics at smaller spatial scales (within a 750 m radius), namely Oxyopes spp. (Araneae: Oxyopidae) and Trichogramma spp., (Hymenoptera: Trichogrammatidae), the proportional-area approach gave a more significant explanation of in-crop density. Herbivore taxa responded weakly to proportional area at all scales and showed no correlation to cost–distance metrics. Findings indicate potential for simplified agricultural landscapes to be ‘selectively’ manipulated to enhance colonization of the crop by natural enemies, but not herbivores, by improving connectivity between crops and non-crop resources, through the presence of woody vegetation.     

Uncertainties in the identification of potential dispersal corridors: The importance of behaviour,sex, and algorithm

Modelling landscape connectivity represents one of the central challenges for conservation of natural resources, especially in human dominated landscapes. Many different methods have been developed to this effect, but their assumptions and limitations have been largely ignored. Using high resolution GPS tracking data from brown bears (Ursus arctos) in central Italy, we investigated the influence of behavioural state (movement vs other behaviours), sex, and algorithms, namely least cost path and circuit theory, on the identification of structural corridors. In particular, considering that most studies does not account for behavioural states and/or individual characteristics, and that basically all studies consider only a single corridor algorithm, we performed (1) a within-algorithm comparison, under the hypothesis that both behavioural states and sex would influence prediction of structural corridors, and (2) a between-algorithm comparison, under the hypothesis that different algorithms would predict different corridors. We found that the impact of sex and/or behavioural state was substantial. On average, least cost path corridors for moving females were 4.7 km apart (st.dev = 7.6 km) from corridors for moving males, and 5.0 km apart (st.dev = 7.2 km) from corridors not considering sex and behaviour. The same was true for circuit theory corridors. The between-algorithm comparison showed that the two corridor models yielded almost identical results, with >80% of the least cost path corridors falling into the two top deciles for the corresponding circuit theory corridors.Our results suggest that the failure to consider an animal’s behavioural state and/or intraspecific differences may result in misidentification of corridors, with potential misallocation of the limited conservation resources available.     

High-use movement pathways and habitat selection by ungulates

The cumulative movements of large mammals are expressed in many areas as semi-permanent wildlife trails. The mapping of semi-permanent trail networks offers a direct approach to assess habitat selection of high-use movement routes at relatively fine spatial scales across a landscape. Here we examine an ungulate trail network in north-central Utah created and maintained by the repeated movements of mule deer (Odocoileus hemionus) and elk (Cervus elaphus). In a resource selection analysis using multivariable spatial regression analysis, we show that at a spatial scale of 70 m open and low cover and distance to water are important predictors of movement pathway density. We also demonstrate at a scale of 10 m that elk and deer movement pathways are less steep than adjacent terrain. The mapping of trail networks should be a particularly useful technique for examining functional connectivity among resource patches across a landscape and identifying important high-use movement routes.     

Evaluating the performance of multiple remote sensing indices to predict the spatial variability of ecosystem structure and functioning in Patagonian steppes

Assessing the spatial variability of ecosystem structure and functioning is an important step towards developing monitoring systems to detect changes in ecosystem attributes that could be linked to desertification processes in drylands. Methods based on ground-collected soil and plant indicators are being increasingly used for this aim, but they have limitations regarding the extent of the area that can be measured using them. Approaches based on remote sensing data can successfully assess large areas, but it is largely unknown how the different indices that can be derived from such data relate to ground-based indicators of ecosystem health. We tested whether we can predict ecosystem structure and functioning, as measured with a field methodology based on indicators of ecosystem functioning (the landscape function analysis, LFA), over a large area using spectral vegetation indices (VIs), and evaluated which VIs are the best predictors of these ecosystem attributes. For doing this, we assessed the relationship between vegetation attributes (cover and species richness), LFA indices (stability, infiltration and nutrient cycling) and nine VIs obtained from satellite images of the MODIS sensor in 194 sites located across the Patagonian steppe. We found that NDVI was the VI best predictor of ecosystem attributes. This VI showed a significant positive linear relationship with both vegetation basal cover (R² = 0.39) and plant species richness (R² = 0.31). NDVI was also significantly and linearly related to the infiltration and nutrient cycling indices (R² = 0.36 and 0.49, respectively), but the relationship with the stability index was weak (R² = 0.13). Our results indicate that VIs obtained from MODIS, and NDVI in particular, are a suitable tool for estimate the spatial variability of functional and structural ecosystem attributes in the Patagonian steppe at the regional scale.     

Spectral K-edge subtraction imaging of experimental non-radioactive barium uptake in bone

PurposeTo evaluate the feasibility of using non-radioactive barium as a bone tracer for detection with synchrotron spectral K-edge subtraction (SKES) technique.MethodsMale rats of 1-month old (i.e., developing skeleton) and 8-month old (i.e., skeletally mature) were orally dosed with low dose of barium chloride (33 mg/kg/day Ba²⁺) for 4 weeks. The fore and hind limbs were dissected for imaging in projection and computed tomography modes at 100 μm and 52 μm pixel sizes. The SKES method utilizes a single bent Laue monochromator to prepare a 550 eV energy spectrum to encompass the K-edge of barium (37.441 keV), for collecting both ‘above’ and ‘below’ the K-edge data sets in a single scan.ResultsThe SKES has a very good focal size, thus limits the ‘crossover’ and motion artifacts. In juvenile rats, barium was mostly incorporated in the areas of high bone turnover such as at the growth plate and the trabecular surfaces, but also in the cortical bone as the animals were growing at the time of tracer administration. However, the adults incorporated approximately half the concentration and mainly in the areas where bone remodeling was predominant and occasionally in the periosteal and endosteal layers of the diaphyseal cortical bone.ConclusionsThe presented methodology is simple to implement and provides both structural and functional information, after labeling with barium, on bone micro-architecture and thus has great potential for in vivo imaging of pre-clinical animal models of musculoskeletal diseases to better understand their mechanisms and to evaluate the efficacy of pharmaceuticals.     

Post-fire dynamics of woody vegetation in seasonally flooded forests (impucas) in the Cerrado-Amazonian Forest transition zone

Fire disturbance alters the structural complexity of forests, above-ground biomass stocks and patterns of growth, recruitment and mortality that determine temporal dynamics of communities. These changes may also alter forest species composition, richness, and diversity. We compared changes in plant recruitment, mortality, and turnover time over three years between burned and unburned sites of two seasonally flooded natural forest patches in a predominantly savanna landscape (regionally called ‘impucas’) in order to determine how fire alters forest dynamics and species composition. Within each impuca, 50 permanent plots (20 m × 10 m) were established and all individuals ≥5 cm diameter at breast height (DBH) identified and measured in two censuses, the first in 2007 and the second in 2010. Unplanned fires burned 30 plots in impuca 1 and 35 in impuca 2 after the first census, which enabled thereafter the comparison between burned and unburned sites. The highest mortality (8.0 and 24.3% year⁻¹ for impuca 1 and 2) and turnover time (69 and 121.5 years) were observed in the burned sites, compared to 3.7 and 5.2% year⁻¹ (mortality), and 28.4 and 40.9 years (turnover), respectively, for the unburned sites. Although these seasonally flooded impuca forests are embedded in a fire-adapted savanna landscape, the impucas vegetation appears to be sensitive to fire, with burned areas having higher mortality and turnover than unburned areas. This indicates that these forest islands are potentially at risk if regional fire frequency increases.     

Tree loss impacts on ecological connectivity: Developing models for assessment

Trees along linear features are important landscape features, and their loss threatens ecological connectivity. Until recently, trees outside of woodlands (TOWs) were largely unmapped however; the development of innovation mapping techniques provides opportunities to understand the distribution of such trees and to apply spatially explicit models to explore the importance of trees for connectivity. In this study, we demonstrate the utility of models when investigating tree loss and impacts on connectivity. Specifically, we investigated the consequences of tree loss due to the removal of roadside trees, a common management response for diseased or damaged trees, on wider landscape functional connectivity. We simulated the loss of roadside trees within six focal areas of the south east of the UK. We used a spatially explicit individual-based modelling platform, RangeShifter, to model the movement of 81 hypothetical actively dispersing woodland breeding species across these agriculturally fragmented landscapes. We investigated the extent to which removal of trees, from roadsides within the wider landscape, affected the total number of successful dispersers in any given year and the number of breeding woodlands that became isolated through time. On average roadside trees accounted for < 2% of land cover, but removing 60% of them (~ 1.2% of land cover) nevertheless decreased the number of successful dispersers by up to 17%. The impact was greatest when roadside trees represented a greater proportion of canopy cover. The study therefore demonstrates that models such as RangeShifter can provide valuable tools for assessing the consequences of losing trees outside of woodlands.     

Spatial metrics for detecting ecosystem degradation in the ridge-slough patterned landscape

Indicators of landscape condition should be selected based on their sensitivity to environmental changes and their capacity to provide early warning detection of those changes. We assessed the performance of a suite of spatial-pattern metrics selected to quantify the condition of the ridge-slough landscape in the Everglades (South Florida, USA). Spatial pattern metrics (n = 14) that describe landscape composition, geometry and hydrologic connectivity were enumerated from vegetation maps of twenty-five 2 × 2 km primary sampling units (PSUs) that span a gradient of hydrologic and ecological condition across the greater Everglades ecosystem. Metrics were assessed in comparison with field measurements from each PSU of landscape condition obtained from regional surveys of soil elevation, which have previously been shown to capture dramatic differences between conserved and degraded locations. Elevation-based measures of landscape condition included soil elevation bi-modality (BI_SE), a binary measure of landscape condition, and also the standard deviation of soil elevation (SD_SE), a continuous measure of condition. Metric performance was assessed based on the strength (sensitivity) and shape (leading vs. lagging) of the relationship between spatial pattern metrics and these elevation-based measures. We observed significant logistic regression slopes with BI_SE for only 4 metrics (slough width, ridge density, directional connectivity index – DCI, and least flow cost – LFC). More significant relationships (n = 8 metrics) were observed with SD_SE, with the strongest associations for slough density, mean ridge width, and the average length of straight flow, as well as for a suite of hydrologic connectivity metrics (DCI, LFC and landscape discharge competence – LDC). Leading vs. lagging performance, inferred from the curvature of the association obtained from the exponent of fitted power functions, suggest that only DCI was a leading metric of the loss of soil elevation variation; most metrics were indeterminate, though some were clearly lagging. Our findings support the contention that soil elevation changes from altered peat accretion dynamics precede changes in landscape pattern, and offer insights that will enable efficient monitoring of the ridge-slough landscape as part of the ongoing Everglades restoration effort.     

An ozone response relationship for four Phleum pratense genotypes based on modelling of the phytotoxic ozone dose (POD)

In the last decade extensive research has focused on the development of dose–response relationships based on stomatal plant ozone uptake (phytotoxic ozone dose, POD). So far most work has concentrated on crops and forest trees. This study provides a flux-based dose–response function for timothy (Phleum pratense), a widespread grassland species, which can be used in risk assessment for ground-level ozone. In 1996 and 2001 timothy was exposed in open-top chambers to ozone concentrations ranging from around 10 nmol mol⁻¹ in the charcoal filtered treatments up to 60 nmol mol⁻¹ in the fumigated treatments (08:00–20:00) in. In 1996 there was a negative effect of ozone on biomass production in the non-filtered treatment while in 2001 no such ozone effect in the non-filtered treatment could be seen. Measurements of stomatal conductance on four timothy genotypes in 2001 were used to calibrate a Jarvis-type multiplicative stomatal conductance model. The maximum conductance varied between the genotypes, from 477 to 589 mmol O₃ m⁻² s⁻¹ (projected leaf area). The model includes functions describing the reduction of stomatal conductance of senescing leaves and the direct effects on stomatal conductance by light, temperature and water vapour pressure deficit. A function describing ozone induced senescence of the leaves was included since exposure to ozone is known to cause premature senescence. The function for ozone was applied when it suggested ozone to be more limiting to stomatal conductance than phenology. To avoid overestimation of stomatal conductance in days with high VPD, a function reflecting the effect on leaf water potential on stomatal conductance was included. Comparison between modelled and measured conductance for the four timothy genotypes resulted in an r² value at 0.57 and a very small average deviation of observed from modelled values. The calibrated stomatal conductance model was used to estimate the accumulated POD, i.e. the accumulated stomatal flux of ozone, of the plants in the 1996 and 2001 experiments. The strongest relationship between ozone relative effects on biomass was obtained when POD was accumulated from 105 degree days after emergence to 1000 degree days after emergence, and integrated using an uptake rate threshold of 7 nmol m⁻² s⁻¹ (POD₇). The response relationship between biomass and POD₇ resulted in an r² value of 0.71 over all four genotypes. This r² value was somewhat higher than for the corresponding relationship based on the accumulated ozone exposure over 40 nmol mol⁻¹ (AOT40; r² = 0.66). With an uptake rate threshold at 7 nmol m⁻² s⁻¹, ozone concentrations above ∼20 nmol mol⁻¹, contribute to reduce the biomass production of timothy if meteorological conditions promote maximum stomatal conductance.     

Vase life of cut rose cultivars ‘Avalanche’ and ‘Fiesta’ as affected by Nano-Silver and S-carvone treatments

Rosa hybrida L. is an important commercial cut flower. The vase life of this flower is usually short due to vascular occlusion. We assessed the effect of Nano-Silver (NS) and S-carvone in prolonging the vase life of R. hybrida L. cv. ‘Avalanche’ and ‘Fiesta’. Hence, an experiment involving the treatment with NS at 0, 50, 100, and 200 mgL^− 1 and S-carvone at 0, 0.25, 0.5, and 0.75 mgL^− 1 with 10 replicates was conducted. Applying NS pulse treatments increased vase life, water uptake rate, and fresh weight and reduced the number of bacteria, water loss, stomatal conductance and transpiration rate. However, S-carvone treatments did not have a positive effect on the vase-life parameters of cut rose flowers. NS pulse treatments increased relative fresh weight (RFW), and water uptake rate (WUR) and decreased water loss (WL) (%) by 10, 89 and 31% for cultivar ‘Avalanche’, compared to the controls, respectively. Application of 200 mgL^− 1 NS led to the highest vase life (18 days) for roses. The results show that NS increased vase life by suppressing stomatal opening, decreasing transpiration from leaves and inhibiting bacterial proliferation.     

Landscape dynamics and their effect on the functional connectivity of a Mediterranean landscape in Chile

Land use and cover changes have been identified as a major factor contributing to shape landscape structure and biodiversity patterns, particulary in areas with a long history of human occupation and habitat fragmentation, such as the Mediterranean landscapes. However, the existing studies on landscape change indicators for Mediterranean areas have mostly focused in Europe, while for other Mediterranean zones, and especially for South America, there is a serious lack of knowledge concerning the impact of landscape dynamics on ecological processes. Further research on this topic is urgently needed, given the high biodiversity levels and the rapidly increasing rates of human modification in the Mediterranean landscapes of South America. For this purpose, we investigated the dynamics of a landscape in the semiarid region of the Mediterranean zone of Chile, and measured the effect of those dynamics on functional connectivity, during a period of about four decades (1975–2011). Landscape connectivity indicators were extracted from a series of Landsat images. The Equivalent Connnected Area index (ECA) was used as indicator of connectivity trends, and was evaluated for three representative distances of seed dispersal in the study area (150 m, 500 m and 1000 m). In addition, the patches that most contribute to maintain the present connectivity, and their roles as connectivity providers, were identified through a set of commensurable indicators: betweenness centrality and the fractions (intra, flux connector) of the Integral Index of Connectivity. We found that these indicators were useful to detect and summarize a number of previously unreported trends in these Mediterranean landscapes. First, population growth and economic development were compatible with an increase in functional connectivity for forest habitats, mainly because the abandonment of marginal agricultural lands and their subsequent conversion to espinals (Acacia caven) triggered vegetation succession towards secondary forests. Second, increased forest connectivity was not associated to a decrease in the characteristic heterogeneity of Mediterranean landscapes. Third, many patches of espinal, despite being commonly regarded as of poor conservation value, were crucial to promote connectivity by acting as stepping stones among other patches with higher habitat quality. The approach here presented provides a combined assessment of landscape structure, function and change that should be valuable and applicable to deliver operational indicators in dynamic landscapes in South America and other Mediterranean regions.     

Trends and inequities in colorectal cancer screening participation in Ontario,Canada, 2005–2011

Background: Participation in screening tests for colorectal cancer (CRC) is generally low in Ontario, Canada. In addition, inequities in participation exist including lower participation among low-income individuals, males and individuals living in rural areas. In April 2008, Colon Cancer Check (CCC) program, the province-wide CRC screening program, was launched in Ontario. This study describes the trends and inequities in CRC screening participation three years before and three years after the CCC, and assesses the effect of the program on CRC screening participation, overall and among certain population groups. Methods: We used administrative data to identify cohorts of individuals eligible for CRC screening in fiscal years 2005–2011. We calculated the age-standardized percent of Fecal Occult Blood Test (FOBT) participation, large bowel endoscopy participation, and being ‘up-to-date’ with CRC screening tests. Results: From 2005 to 2011, FOBT participation increased from 7.6% to 14.8%, large bowel endoscopy participation from 3.4% to 5.7%, and ‘up-to-date’ with CRC screening from 27.2% to 41.3%. Before the launch of the CCC program, the quarterly increase in FOBT participation was 0.07% (p = 0.19), increased immediately after the launch (1.8%, p < 0.01), followed by a decline (?0.08%, p = 0.08), returning to its pre-program increase rate. We noted a significant decrease in FOBT participation every summer (?0.44%, p < 0.01). The CCC program had minimal effect on large bowel endoscopy participation. Before the launch of the CCC program, the quarterly increase in ‘up-to-date’ with CRC screening was 0.9% (p < 0.01), increased immediately after the launch (2.5%, p = 0.05), followed by a modest decline thereafter (?0.59%, p < 0.02). From 2005 to 2011, recent residents living in low-income neighborhoods were consistently and significantly less likely to have a FOBT and be ‘up-to-date’ with CRC screening than long-term residents living in high-income neighborhoods (2.9–4.5%; 14.7–17.3% respectively). Pre-CCC inequities in CRC participation persisted after the launch of the program. Conclusion: CRC testing was increasing in Ontario from 2005. An immediate increase in CRC testing, FOBT in particular, occurred after the launch of the CCC program, followed by a return to its pre-CCC increase rate thereafter. Future efforts are needed to improve screening participation and address inequities.     

Partitioning of latent heat flux at a northern peatland

The partitioning of latent heat flux (Q_E) to vascular plant and moss surface components was assessed for a Sphagnum-dominated bog with a hummock–hollow surface having a sparse canopy of low shrubs. Results from porometry and eddy covariance measurements of Q_E showed evaporation from the moss surface ranged from greater than 50% of total Q_E early in the growing season to less than 20% after a dry period toward the end of the growing season. Both soil moisture and vapour pressure deficit (D_a) affected this partitioning with drier moss and peat, lower water table, and smaller D_a all reducing moss Q_E. Daily maximum moss Q_E ranged from greater than 200 W m⁻² early in the growing season to less than 100 W m⁻² during a dry period. In contrast, vascular contribution to total Q_E increased over the season from a daily maximum of about 150 W m⁻² to 250 W m⁻² due to increase in leaf area by leaf replacement and emergence and to drying of the moss surface. Porometry results showed average daily maximum conductance from bog shrubs was near 8 mm s⁻¹. These conductance values were smaller than those reported for vascular plants from more nutrient-rich wetlands. The effect of increases in D_a on vascular Q_E were moderated by decreases in stomatal conductance. At constant available energy, vascular leaf conductance was reduced by as much as 2 mm s⁻¹ and moss surface conductance was enhanced by up to 3 mm s⁻¹ by large D_a. Considering vascular and non-vascular water transport characteristics and frequency of water table position and given the observed variations of Q_E partitioning with water table location and moss and peat water content, it is suggested that modelling efforts focus on how dry hummocks and wet hollows each contribute to Q_E, especially as related to D_a and soil moisture dynamics.     

Effects of flooding on photosynthesis and root respiration in saltcedar (Tamarix ramosissima), an invasive riparian shrub

The introduced shrub Tamarix ramosissima invades riparian zones, but loses competitiveness under flooding. Metabolic effects of flooding could be important for T. ramosissima, but have not been previously investigated. Photosynthesis rates, stomatal conductance, internal (intercellular) CO₂, transpiration, and root alcohol dehydrogenase (ADH) activity were compared in T. ramosissima across soil types and under drained and flooded conditions in a greenhouse. Photosynthesis at 1500 μmol quanta m⁻² s⁻¹ (A₁₅₀₀) in flooded plants ranged from 2.3 to 6.2 μmol CO₂ m⁻² s⁻¹ during the first week, but A₁₅₀₀ increased to 6.4–12.7 μmol CO₂ m⁻² s⁻¹ by the third week of flooding. Stomatal conductance (g_s) at 1500 μmol quanta m⁻² s⁻¹ also decreased initially during flooding, where g_s was 0.018 to 0.099 mol H₂O m⁻² s⁻¹ during the first week, but g_s increased to 0.113–0.248 mol H₂O m⁻² s⁻¹ by the third week of flooding. However, photosynthesis in flooded plants was reduced by non-stomatal limitations, and subsequent increases indicate metabolic acclimation to flooding. Root ADH activities were higher in flooded plants compared to drained plants, indicating oxygen stress. Lower photosynthesis and greater oxygen stress could account for the susceptibility of T. ramosissima at the onset of flooding. Soil type had no effect on photosynthesis or on root ADH activity. In the field, stomatal conductance, leaf water potential, transpiration, and leaf δ¹³C were compared between T. ramosissima and other flooded species. T. ramosissima had lower stomatal conductance and water potential compared to Populus deltoides and Phragmites australis. Differences in physiological responses for T. ramosissima could become important for ecological concerns.     

Delirium prevalence in a Colombian hospital,association with geriatric syndromes and complications during hospitalization

BackgroundThe aim of this paper is to describe the prevalence of Delirium and the factors associated with its presentation and complications identified in a geriatric unit in Colombia.Material and methodsThis is a retrospective observational study that included all patients admitted consecutively for two years in a geriatric unit of a hospital in Bogotá, Colombia. We assessed delirium prevalence with the Confusion Assessment Method (CAM). The independent variables were age, sex, functional impairment (Barthel < 90), malnutrition (MNA < 12), pressure ulcers at admission, state of the social support network, number of comorbidities, polypharmacy (5 or more drugs), complications such as ICU requirement, hospital stay, in-hospital functional impairment and mortality were also evaluated. As an exclusion criterion: not having CAM registered in the medical record, all the patients had this information.ResultsWe studied 1599 subjects with a mean age of 86 years (IQR 9). Delirium prevalence was 51.03%. Delirium was associated with a higher rate of: pressure ulcers on admission [OR 3.76 (CI 2.60–5.43 p < 0.001)], functional impairment [OR 2.38 (CI 1.79–3.16 p < 0.001)], malnutrition [OR 2.06 (CI 1.56–2.73 p < 0.001)], and infection [OR 1.46 (CI 1.17–1.82 p < 0.001)]. Moreover delirium has a higher association with mortality [OR 2.80 (1.03–7.54 p = 0.042)], in-hospital functional decline [OR 1.82 (1.41–2.36 p < 0.001)], and longer hospital stay [OR 1.04 (1.04–1.09 p = 0.006)]; independently of age, sex, pressure ulcers on admission, functional impairment, malnutrition, dementia, infection and limited social network.ConclusionOur study suggests that infectious diseases and geriatric syndromes such as, functional dependence, pressure ulcers, malnutrition or major cognitive impairment are independently associated with the presence of delirium on admission. Additionally, the presence of delirium is independently associated during hospitalization with complications, longer hospital stay, functional impairment and mortality.     

Dragon's blood dropping pills have protective effects on focal cerebral ischemia rats model

Dragon's blood is a bright red resin obtained from Dracaena cochinchinensis (Lour.) S.C.Chen (Yunnan, China). As a traditional Chinese medicinal herb, it has great traditional medicinal value and is used for wound healing and to stop bleeding. Its main biological activity comes from phenolic compounds. In this study, phenolic compounds were made into dropping pills and their protective effects were examined by establishing focal cerebral ischemia rats model used method of Middle Cerebral Artery Occlusion (MCAO), and by investigating indexes of neurological scores, infarct volume, cerebral index, cerebral water content and oxidation stress. Compared to model group, high, middle and low groups of Dragon's blood dropping pills could improve the neurological function significantly (p < 0.01) and reduce cerebral infarct volume of focal cerebral ischemia rats remarkably (p < 0.05–0.01). Meanwhile, each group could alleviate cerebral water content and cerebral index (p < 0.05–0.01) and regulate oxidative stress of focal cerebral ischemia rats obviously (p < 0.05–0.01). Activities of middle group corresponded with that treated with positive control drug. The results obtained here showed that Dragon's blood dropping pills had protective effects on focal cerebral ischemia rats.     

Parkinson’s disease and sex-related differences in electromyography during daily life

Scope: Daily bilateral electromyography (EMG) recordings reveal muscle activation patterns implicated in asymmetric Parkinson’s disease (PD)-related functional decline. Also, daily EMG recordings reveal sex-differences in muscle activity that give rise to unique PD presentation in males and females. Purpose: Quantify handgrip strength and daily muscle quiescence through analysis of gaps in the EMG signal in males and females with PD. Bilateral daily EMG was recorded and normalized to maximal voluntary exertions (MVE). EMG gap was defined as <1% amplitude of MVE for >0.1 s and characterized as number, duration and time occupied by gaps. A dynamometer evaluated maximal grip-strength. Three-way repeated measures ANOVA examined differences in gap characteristics and strength. Gap duration was shorter (p = 0.04) and occupied less time (p = 0.02) in PD than controls. Females had fewer gaps with shorter duration (p = 0.004), occupying less time (p = 0.004) compared with males. Gaps were fewer (p = 0.04) and occupied less time (p = 0.01) on more-affected than less-affected side. PD was weaker than controls (p = 0.04), females were weaker than males (p = 0.00), and the more-affected PD side was weaker than less-affected (p = 0.04). Conclusions: Quantification of muscle quiescence through gaps in the EMG signal recorded during daily life provides insight into mechanisms underlying differential change in functional performance in males and females with PD.