Search

Objective: To explore the relationship between physical activity level, muscle strength, working memory and cognitive function in older adults. Methods: A cross-sectional research design was employed to recruit 120 older adults individuals aged 70 and above. Participants were asked to complete the International Physical Activity Questionnaire-Short Form and the Montreal Cognitive Assessment Scale. Data on variables such as grip strength and performance on the N-back task were collected. Data analysis involved the use of independent samples t-tests, χ² tests, linear regression analysis, Pearson correlation analysis, and one-way analysis of variance (ANOVA). Results: The detection rate of cognitive dysfunction in older adults was 53.211%; 1-back correct rate had an explanatory power of 11.6% for the cognitive function scores of older adults (R²   =  0.116, p  <  0.001); grip strength showed a significant positive correlation with 1-back correct rate (r  =  0.417, p  <  0.001), and was significantly correlated with the 0-back response time (r  = −0.478), 1 -back response time (r  = −0.441) were significantly negatively correlated (p  <  0.001); physical activity level was significantly positively correlated with grip strength (r  =  0.559, p  <  0.001), and the difference in grip strength among older adults with different physical activity levels was statistically significant (F  =  19.685, p  <  0.001). Conclusion: Physical activity level, muscle strength, working memory, and cognitive function are closely related in older adults, and the relational pathway of physical activity → muscle strength → working memory → cognitive function may serve as a useful addition to promote the field of cognitive research in older adults. To identify and prevent cognitive decline in older adults, physical activity questionnaires, grip strength tests, and 1-back task tests can be extended to nursing homes and communities. [ABSTRACT FROM AUTHOR]

Despite belonging to the most abundant and widespread genus of freshwater fishes in the region, the carp gudgeons of eastern Australia (genus Hypseleotris) have proved taxonomically and ecologically problematic to science since the 19th century. Several molecular studies and a recent taxonomic revision have now shed light on the complex biology and evolutionary history that underlies this group. These studies have demonstrated that carp gudgeons include a sexual/unisexual complex (five sexual species plus an assortment of hemiclonal lineages), many members of which also co‐occur with an independent sexual relative, the western carp gudgeon (H. klunzingeri). Here, we fill yet another knowledge gap for this important group by presenting a detailed molecular phylogeographic assessment of the western carp gudgeon across its entire and extensive geographic range. We use a suite of nuclear genetic markers (SNPs and allozymes) plus a matrilineal genealogy (cytb) to demonstrate that H. klunzingeri s.l. also displays considerable taxonomic and phylogeographic complexity. All molecular datasets concur in recognizing the presence of multiple candidate species, two instances of historic between‐species admixture, and the existence of a natural hybrid zone between two of the three candidate species found in the Murray–Darling Basin. We also discuss the major phylogeographic patterns evident within each taxon. Together, these analyses provide a robust molecular, taxonomic, and distributional framework to underpin future morphological and ecological investigations on this prominent member of regional freshwater ecosystems in eastern Australia. [ABSTRACT FROM AUTHOR]

Background: Exercise can improve cognition in aging, however it is unclear how exercise influences cognition, and sleep may partially explain this association. The current study aimed to investigate whether objectively measured sleep mediates the effect of an acute exercise intervention on cognition in older adults. Methods: Participants were 30 cognitively unimpaired, physically active older adults (69.2 ± 4.3 years) with poor sleep (determined via self-report). After a triple baseline cognitive assessment to account for any natural fluctuation in cognitive performance, participants completed either a single bout of 20-minutes of high intensity exercise on a cycle ergometer, or a control condition, in a cross-over trial design. Cognition was measured immediately post-intervention and the following day, and sleep (total sleep time, sleep onset latency, sleep efficiency, % of rapid eye movement sleep, light sleep and deep sleep) was characterized using WatchPAT™ at baseline (5 nights) and measured for one night after both exercise and control conditions. Results: Results showed no effect of the exercise intervention on cognition immediately post-intervention, nor an effect of acute exercise on any sleep variable. There was no mediating effect of sleep on associations between exercise and cognition. However, a change from baseline to post-intervention in light sleep and deep sleep did predict change in episodic memory at the ~24 h postintervention cognitive assessment, regardless of intervention condition. Discussion: There was no effect of acute high intensity exercise on sleep or cognition in the current study. However, results suggest that associations between sleep and cognition may exist independently of exercise in our sample. Further research is required, and such studies may aid in informing the most effective lifestyle interventions for cognitive health. [ABSTRACT FROM AUTHOR]

Earthquake‐driven subsidence can cause cascading hazards at the coast by exacerbating relative sea level rise, storm surges, tsunami, and tidal flooding. At Ahuriri Lagoon near Napier, Aotearoa New Zealand, paleoseismic uplift and subsidence are typically attributed to upper plate faults and subduction interface earthquakes, respectively. We test this assumption with elastic dislocation models of upper plate and subduction interface earthquakes informed by historical events, seismic surveys, and modern interface coupling data. We compared our surface deformation results to paleoseismic records preserved at Ahuriri Lagoon, which includes eight rapid subsidence (c. 0.5–1.2 m) and two rapid uplift events over the last c. 7 kyr. Our models demonstrate that offshore upper plate faults could cause subsidence of c. 0.5–1 m at Ahuriri Lagoon at recurrence intervals of c. 2 kyr. A range of subduction interface earthquakes can also produce subsidence at Ahuriri Lagoon, and may explain larger (>1 m) subsidence, but must rupture the currently creeping (i.e., aseismic) portions of the interface. We demonstrate that both upper plate fault and subduction interface earthquakes may have contributed to the Ahuriri Lagoon records, and that interface coupling may be more spatially or temporally heterogeneous than modern geodetic data suggest. Models of sea‐level rise and earthquake multi‐hazards that do not include the effects of upper plate faulting may mischaracterize risk at the coast. Plain Language Summary: Earthquakes can cause land to uplift or subside. If land subsides along the coastline, it becomes more susceptible to flooding, storm waves, tsunami, and ongoing sea level rise. The geologic record at Ahuriri Lagoon near Napier, New Zealand, shows that earthquakes have caused subsidence of at least 0.5 m many times over the last 7,000 years. We modeled how earthquakes on different faults, such as the subduction zone or smaller crustal faults above it, would vertically move the coastline. We found that both types of earthquakes have likely caused subsidence at Ahuriri Lagoon, which differs from past interpretations that focus mainly on subduction zone earthquakes. Additionally, the subduction earthquakes that cause subsidence at Ahuriri Lagoon are not in the expected location based on modern instrumental data. Therefore, future hazard models may need to take into account a broader range of earthquake source faults and more complex earthquake scenarios. Key Points: Elastic dislocation modeling shows that listric upper plate faults can cause coastal coseismic subsidence above the down‐dip rupture limitCoseismic subsidence at a key site (Ahuriri Lagoon, central Hikurangi margin) can be caused by both upper‐plate and subduction earthquakesSubduction seismic cycle interpretations using coseismic uplift and subsidence records should consider the influence of upper plate faults [ABSTRACT FROM AUTHOR]

SPG7 is the most common form of autosomal recessive hereditary spastic paraplegia (HSP). There is a lack of HSP-SPG7 human neuronal models to understand the disease mechanism and identify new drug treatments. We generated a human neuronal model of HSP-SPG7 using induced pluripotent stem (iPS) cell technology. We first generated iPS cells from three HSP-SPG7 patients carrying different disease-causing variants and three healthy controls. The iPS cells were differentiated to form neural progenitor cells (NPCs) and then from NPCs to mature cortical neurons. Mitochondrial and neuronal defects were measured using a high throughout imaging and analysis-based assay in live cells. Our results show that compared to control NPCs, patient NPCs had aberrant mitochondrial morphology with increased mitochondrial size and reduced membrane potential. Patient NPCs develop to form mature cortical neurons with amplified mitochondrial morphology and functional defects along with defects in neuron morphology - reduced neurite complexity and length, reduced synaptic gene, protein expression and activity, reduced viability and increased axonal degeneration. Treatment of patient neurons with Bz-423, a mitochondria permeability pore regulator, restored the mitochondrial and neurite morphological defects and mitochondrial membrane potential back to control neuron levels and rescued the low viability and increased degeneration in patient neurons. This study establishes a direct link between mitochondrial and neuronal defects in HSP-SPG7 patient neurons. We present a strategy for testing mitochondrial targeting drugs to rescue neuronal defects in HSP-SPG7 patient neurons. [ABSTRACT FROM AUTHOR]

In many situations, species distribution models need to make use of multiple data sources to address their objectives. We developed a spatio-temporal modelling framework that integrates research survey data and data collected by observers onboard fishing vessels while accounting for physical barriers (islands, convoluted coastlines). We demonstrated our framework for two bycatch species in New Zealand deepwater fisheries: spiny dogfish (Squalus acanthias) and javelinfish (Lepidorhynchus denticulatus). Results indicated that employing observer-only data or integrated data is necessary to map fish biomass at the scale of the New Zealand exclusive economic zone, and to interpolate local biomass indices (e.g. for the east coast of the South Island) in years with no survey but available observer data. Results also showed that, if enough survey data are available, fisheries analysts should: (1) develop both an integrated model and a model relying on survey-only data; and (2) for a given geographic area, ultimately choose the index produced with integrated data or the index produced with survey-only data based on the reliability of the interannual variability of the index. We also conducted a simulation experiment, which indicated that the predictions of our spatio-temporal models are virtually insensitive to the consideration of physical barriers. [ABSTRACT FROM AUTHOR]

We construct a model of forces at the New Zealand plate boundary from dynamical thin‐sheet modeling. Stress magnitudes estimated are 10–50 MPa and effective viscosities are 0.5–5 × 1021 Pa s within actively deforming regions. Models that include only far‐field forces and forces from variations in topography and bathymetry can fit observations in most of the plate boundary, but basal tractions are required to fit extension in Havre Trough. For models that include nontopographic forces, we specify a rheology to acquire a unique solution for each of three rheologies: power‐law rheology with n = 3, power law with n = 5, and a pseudo‐plastic equal‐stress rheology. The inclusion of nontopographic forces allows these models to fit observations very well. We predict forces in Havre Trough equivalent to basal tractions of 7–10 MPa at 20‐km depth. Models with n = 3 and n = 5 require antiparallel forces on opposite sides of the plate boundary to drive deformation in South Island which would imply a plate boundary zone that is more localized at depth. The equal‐stress pseudo‐plastic model drives deformation with plate motion boundary conditions and localizes it with variations in effective viscosity. The effective rheology of South Island is most realistically modeled by an equal‐stress pseudo‐plastic rheology. The n = 3 or n = 5 power‐law rheology models require a highly localized boundary zone in the lower lithosphere, but a broader zone in the upper lithosphere. Plain Language Summary: New Zealand is prone to earthquakes because it lies on the boundary between two tectonic plates. Plates are the strong outer shell of the Earth that is broken into moving pieces. We construct a set of models of forces at the New Zealand plate boundary, to better understand why plates move. Tectonic forces originate in three ways: (a) transmitted through the plate from far away; (b) from topography that gravity is trying to make collapse; and (c) from local tractions between the shallow plate and differential movements deeper within the Earth. We find that local forces are needed to fit all observations, but not all our models seem realistic. The model that is most plausible has tectonic stresses that are approximately even across the plate boundary region, rather than being much higher within the deforming zone. Our estimates of tectonic stress are similar or slightly larger than previous estimates and we can fit all observations of how the faults in New Zealand are moving. Key Points: Stress magnitudes are 10–50 MPa and effective viscosities are 0.5–5 × 1021 Pa s in actively deforming regions of New ZealandExtension in Havre Trough is driven by local, nontopographic forces that are equivalent in magnitude to basal tractions of 7–10 MPaRheology of lithosphere in South Island plausibly fits a pseudo‐plastic model, while power‐law models require unlikely force patterns [ABSTRACT FROM AUTHOR]

Significant variations in pore pressure across the Taranaki Basin, New Zealand, are attributed to changes in lithofacies and structure, usefully illustrated in terms of ten areas that we term geopressure provinces, each displaying individual pore pressure trends. Cretaceous to Early Miocene formations in different parts of the basin can be either normally pressured (near or at hydrostatic) or significantly overpressured (up to 28 MPa) at the same depth. Variations in Eocene–Oligocene facies types and thicknesses both within and between geopressure provinces provide first‐order control on the magnitude, distribution and maintenance of overpressure across the basin. Examples of hydraulic compartmentalisation due to sealing faults and stratigraphic architecture are identified within the basin. Deep pore pressure transitions are sealed by diagenetic, structural or stratigraphic mechanisms in different places and are associated with an increase in mudrock volume (reduced permeability) or gas generation. Thus, pore pressure distribution in the Taranaki Basin is controlled by a combination of sediment loading, lithofacies variations, fault zone permeability and structural architecture. This work represents an appraisal of the pore pressure distribution across the whole of a multiphase structurally complex basin, and the approach taken provides a framework for better understanding the distribution of pore fluid pressures and pore fluid migration in other sedimentary basins. [ABSTRACT FROM AUTHOR]

HSP-SPAST is the most common form of hereditary spastic paraplegia (HSP), a neurodegenerative disease causing lower limb spasticity. Previous studies using HSP-SPAST patient-derived induced pluripotent stem cell cortical neurons have shown that patient neurons have reduced levels of acetylated a-tubulin, a form of stabilized microtubules, leading to a chain of downstream effects eventuating in increased vulnerability to axonal degeneration. Noscapine treatment rescued these downstream effects by restoring the levels of acetylated a-tubulin in patient neurons. Here we show that HSP-SPAST patient non-neuronal cells, peripheral blood mononuclear cells (PBMCs), also have the disease-associated effect of reduced levels of acetylated a-tubulin. Evaluation of multiple PBMC subtypes showed that patient T cell lymphocytes had reduced levels of acetylated a-tubulin. T cells make up to 80% of all PBMCs and likely contributed to the effect of reduced acetylated a-tubulin levels seen in overall PBMCs. We further showed that mouse administered orally with increasing concentrations of noscapine exhibited a dose-dependent increase of noscapine levels and acetylated a-tubulin in the brain. A similar effect of noscapine treatment is anticipated in HSP-SPAST patients. To measure acetylated a-tubulin levels, we used a homogeneous time resolved fluorescence technologybased assay. This assay was sensitive to noscapine-induced changes in acetylated a-tubulin levels in multiple sample types. The assay is high throughput and uses nano-molar protein concentrations, making it an ideal assay for evaluation of noscapine-induced changes in acetylated a-tubulin levels. This study shows that HSP-SPAST patient PBMCs exhibit disease-associated effects. This finding can help expedite the drug discovery and testing process. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine hospital costs and revenue of universal opt-out HIV ED screening. An electronic medical record (EMR)-directed, automated ED screening program was instituted at an academic medical center in San Diego, California. A base model calculated net income in US dollars for the hospital by comparing annual testing costs with reimbursements using payor mixes and cost variables. To account for differences in payor mixes, testing costs, and reimbursement rates across hospitals in the US, we performed a probabilistic sensitivity analysis. The base model included a total of 12,513 annual 4th generation HIV tests with the following payor mix: 18% Medicare, 9% MediCal, 28% commercial and 8% self-payers, with the remainder being capitated contracts. The base model resulted in a net profit for the hospital. In the probabilistic sensitivity analysis, universal 4th generation HIV screening resulted in a net profit for the hospital in 81.9% of simulations. Universal 4th generation opt-out HIV screening in EDs resulted in a net profit to an academic hospital. Sensitivity analysis indicated that ED HIV screening results in a net-profit for the majority of simulations, with higher proportions of self-payers being the major predictor of a net loss. [ABSTRACT FROM AUTHOR]

Well-known analytical approaches are commonly adopted for the preliminary design of scramjet engines. In this context, the combustion process in the combustion chamber can be modeled by considering heat addition to the airflow at supersonic speed. The one-dimensional Rayleigh flow theory can be applied to estimate the behavior of thermodynamic properties and velocities when the combustion chamber has a constant cross-sectional area and no mass is added within the duct. However, the temperature and pressure predicted by using constant area combustion chambers are too high, implying the necessity of modifications in the cross-sectional area of the chamber to avoid thermal choking and excessive pressure gradients. In this case, the unidimensional Rayleigh theory does not fit anymore. This work proposes an analytical methodology to estimate the airflow thermodynamic properties and velocities for scramjet combustion chambers with cross sections of variable areas by using an iterative algorithm that employs the Rayleigh flow area ratio theory. The analytical results were compared with the two-dimensional computational fluid dynamics analysis using the Reynolds-averaged Navier–Stokes method for both inviscid and viscous flow and considering turbulence effects. The proposed analytical model to estimate the flow behavior in the scramjet combustion chamber predicted results in agreement with the physics of the problem and with the results obtained via numerical simulation. The analytical model cannot predict oscillations in the flow properties caused by the expansion waves and their reflections. Still, the behavior and intensity of the properties are well captured along the entire length of three combustion chambers with variable area. The proposed algorithm is also applied to determine the angle of the combustion chamber that allows guaranteeing a constant, or a quasi-constant, static pressure along the length of the combustion chamber, approaching better the ideal thermodynamic Brayton cycle. The proposed model is suitable for preliminary scramjet designs and can be used to solve other problems involving variable area ducts. [ABSTRACT FROM AUTHOR]

Climate change and the predicted warmer temperatures and more extreme hydrological regimes could affect freshwater ecosystems and their energy pathways. To appreciate the complex spatial and temporal interactions of carbon cycling in flowing waters, ecosystem metabolism (gross primary production [GPP] and ecosystem respiration [ER]) must be resolved at the scale of an entire river network. Here, we propose a meta‐ecosystem framework that couples light and temperature regimes with a reach‐scale ecosystem model and integrates network structure, catchment land cover, and the hydrologic regime. The model simulates the distributed functioning of dissolved and particulate organic carbon, autotrophic biomass, and thus ecosystem metabolism, and reproduces fairly well the metabolic regimes observed in 12 reaches of the Ybbs River network, Austria. Results show that the annual network–scale metabolism was heterotrophic, yet with a clear peak of autotrophy in spring. Autochthonous energy sources contributed 43% of the total ER. We further investigated the effect of altered thermal and hydrologic regimes on metabolism and ecosystem efficiency. We predicted that an increase of 2.5°C in average stream water temperature could boost ER and GPP by 31% (24%–57%) and 28% (5%–57%), respectively. The effect of flashier hydrologic regimes is more complex and depends on autotrophic biomass density. The analysis shows the complex interactions between environmental conditions and biota in shaping stream metabolism and highlights the existing knowledge gaps for reliable predictions of the effects of climate change in these ecosystems. Plain Language Summary: Organic carbon is one of the main source of energy sustaining riverine ecosystems. It can be internally produced by autotrophic organisms, or subsidized from the adjacent terrestrial ecosystem. Understanding the fraction of organic carbon which is metabolized within a stream network rather than exported to downstream ecosystems, and how such fraction is controlled by the thermal and hydrologic regime, is crucial to predict the whole ecosystem function, the ecosystem services it can provide, and the regional (and global) carbon cycling. Through the development of a mathematical model applied to a well‐monitored river network, the paper addresses this fundamental question and attempts to predict how these energetic fluxes might be affected by climate change. Key Points: The framework simulates temporal dynamics of ecosystem metabolism at the stream network scaleThe effect of climate change on network‐scale metabolism and carbon spiraling is investigatedA temperature increase of 2.5 C will boost ecosystem respiration and gross primary production by 31% (24%–57%) and 28% (5%–57%), respectively [ABSTRACT FROM AUTHOR]

Copyright of Fenerbahce University Journal of Health Sciences (FBU-JOSH) / Fenerbahçe Üniversitesi Sağlık Bilimleri Dergisi is the property of Fenerbahce University Journal of Health Sciences (FBU-JOSH) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Deep‐water corals are protected in the seas around New Zealand by legislation that prohibits intentional damage and removal, and by marine protected areas where bottom trawling is prohibited. However, these measures do not protect them from the impacts of a changing climate and ocean acidification. To enable adequate future protection from these threats we require knowledge of the present distribution of corals and the environmental conditions that determine their preferred habitat, as well as the likely future changes in these conditions, so that we can identify areas for potential refugia. In this study, we built habitat suitability models for 12 taxa of deep‐water corals using a comprehensive set of sample data and predicted present and future seafloor environmental conditions from an earth system model specifically tailored for the South Pacific. These models predicted that for most taxa there will be substantial shifts in the location of the most suitable habitat and decreases in the area of such habitat by the end of the 21st century, driven primarily by decreases in seafloor oxygen concentrations, shoaling of aragonite and calcite saturation horizons, and increases in nitrogen concentrations. The current network of protected areas in the region appear to provide little protection for most coral taxa, as there is little overlap with areas of highest habitat suitability, either in the present or the future. We recommend an urgent re‐examination of the spatial distribution of protected areas for deep‐water corals in the region, utilising spatial planning software that can balance protection requirements against value from fishing and mineral resources, take into account the current status of the coral habitats after decades of bottom trawling, and consider connectivity pathways for colonisation of corals into potential refugia. [ABSTRACT FROM AUTHOR]