Maximum Elevation Research Articles

Potential elevation of exopeptidase activity of Glu-specific endopeptidase I/GluV8 mediated by hydrophobic P1′-position amino acid residue

We recently reported that the activities of dipeptidyl-peptidase (DPP)7 and DPP11, S46-family exopeptidases were significantly elevated by the presence of prime-side amino acid residues of substrates caused by an increase in kcat [Ohara-Nemoto Y. et al., J Biol Chem 298(3):101585. doi: 10.1016/j.jbc.2022]. In the present study, the effects of prime-side residues on Glu-specific endopeptidase I/GluV8 from Staphylococcus aureus were investigated using a two-step cleavage method with tetrapeptidyl-methycoumaryl-7-amide (MCA) carrying P2- to P2′-position residues coupled with DPP11 as the second enzyme. GluV8 showed maximal activity toward benzyloxycarbonyl (Z)-LLE-MCA, while the effects of hydrolysis of substrates one residue shorter, such as acetyl (Ac)-Val-Glu- and Leu-Glu-MCA, were negligible. Nevertheless, activity towards Ac-VE-|-ID-MCA, a substrate carrying P1′ and P2′ residues, emerged and reached a level 44 % of that for Z-LLE-MCA. Among 11 Ac-HAXD-MCA (X is a varied amino acid), the highest level of activity enhancement was achieved with P1′-Leu and Ile, followed by Phe, Val, Ser, Tyr, and Ala, while Gly and Lys showed scant effects. This activation order was in parallel with the hydrophobicity indexes of these amino acids. The prime-side residues increased kcat/KM primarily through a maximum 500-fold elevation of kcat as well as S46-family exopeptidases. The MEROPS substrate database also indicates a close relationship between activity and hydrophobicity of the P1′ residues in 93 N-terminal-truncated substrates, though no correlation was observed among all 4328 GluV8 entities examined. Taken together, these results are the first to demonstrate N-terminal exopeptidase activity of GluV8, considered to be prompted by hydrophobic P1′ amino acid residues.

Ambient PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) associated with pro-thrombotic biomarkers among young healthy adults: A 16 times repeated measurements panel study

Studies have shown that the cardio/cerebrovascular toxicity of ambient PM2.5 is related to its bound polycyclic aromatic hydrocarbons (PAHs). Currently, only a few studies have reported the relationship between PM2.5-bound PAHs and promoted blood coagulation and thrombosis, but there isn't a consistent conclusion. Therefore, we conducted a prospective panel study to investigate the association. Thirty-three young healthy adults participated in sixteen repeated visits from 2014 to 2018 in Tianjin, China. During each visit, three pro-thrombotic biomarkers: ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin motif 13), D-dimer and Myeloperoxidase (MPO) were measured. Before each visit, ambient PM2.5 samples were daily collected for one week. Sixteen PAHs were determined using Gas Chromatography-Mass Spectrometer, and the positive matrix factorization (PMF) model was applied to identify the sources. Linear mixed-effects models were fitted to investigate the associations between PM2.5-bound PAHs exposure and the biomarkers. Thirteen time-metrics were defined to identify significant time points of PM2.5-bound PAHs' effects. We observed that the increase of PM2.5-bound PAHs exposure was significantly associated with reduced ADAMTS13, elevated D-dimer and MPO. At lag0, each 5.7 ng/m3 increase in Benzo[j]fluoranthene and per 3.4 ng/m3 increase Dibenz[a,h]anthracene could make a maximum change of −19.08 % in ADAMTS13 and 132.60 % in D-dimer. Additionally, per 16.43 ng/m3 increase in Chrysene could lead to a maximum elevation of 32.14 % in MPO at lag4. The PM2.5-bound PAHs often triggered more significant changes at lag 3,4 and 6. The ambient PM2.5-bound PAHs originated from six sources: coal combustion (43.10 %), biomass combustion (20.77 %), diesel emission (14.78 %), gasoline emission (10.95 %), industrial emission (7.58 %), and cooking emission (2.83 %). The greatest contributors to alterations in ADAMTS13, D-dimer and MPO are industrial emission (−48.43 %), biomass combustion (470.32 %) and diesel emission (13.14 %) at lag4. Our findings indicated that short-term exposure to ambient PM2.5-bound PAHs can induce alterations of pro-thrombotic biomarkers among healthy adults.

Influence of meteorological conditions in autumn/winter 2021–2022 on the development of storm surges and the dune erosion on the Polish Baltic coast as a result of climate . . . . 93

This paper presents details of 37 storm surges that occurred on the Polish southern Baltic Sea coast in the autumn/winter 2021–2022 season. They emerged during the passage of a larger number of low-pressure systems than usual from the SW-W direction over the Baltic Sea. Based on an assessment of meteorological and hydrological conditions during the storms, the relationship between the wind parameters, the sea level increase, and its maximum elevation was ascertained. The relationship between the sea level and the run-up elevation was ascertained. The elevation of the sea level and run-up on the onshore were compared with the beach height. Sections with a lower beach were affected by dune erosion already at a lower sea level. The dependence of dune erosion on the sea level elevation was presented. The value of the dune base retreat depended on the beach elevation and the sea level expressed by the onshore flow called run-up. The most significant erosion occurred during the storm Nadine with a sea level of 1.0–1.28 m AMSL. The average erosion varied between 1.0 and 4.5 m. The maximum erosion values reached 8–13 m.

Determination of left ventricular ejection fraction and C-reactive protein by the state of ischemic myocardium – capabilities of ECG digitalization

Aim. To determine the dependence of left ventricular ejection fraction (LVEF) and C-reactive protein (CRP) on the condition of ischemic myocardium considering additional diagnostic data, obtained from differentiated ECG. Material and methods. To achieve the goal, 135 patients with coronary artery disease (CAD) were examined and divided into comparison groups: 48 patients with LVEF <55 % and 87 patients with LVEF ≥55 %. ST-elevation myocardial infarction (STEMI) was diagnosed in 45 of 135 patients, who were grouped according to LVEF: 17 patients with LVEF <50 % and 28 patients with LVEF ≥50 %. Stable angina (SA) was documented in 90 of 135 patients, who were assigned to groups depending on LVEF: 51 patients with LVEF <60 % and 39 patients with LVEF ≥60 %. Depending on the CRP level, 2 SA groups numbering 46 people were formed: 18 patients with a level of CRP ≥0.5 mg/dL and 28 patients with a level of CRP <0.5 mg/dL. The study included clinical examinations, questionnaire, analysis of biomarkers and data of functional methods of examination (echocardiography, coronary ventriculography, ECG digitalization with the assessment of its parameters based on the “Smart-ECG” medical software platform). Results. Patients with CAD and LVEF<55 % had higher values of endothelin-1 (ET-1) (10.21 (7.69; 11.65) pg/ml, Δ +41.81 %, p = 0.040), slightly higher levels of CRP (0.53 (0.35; 0.70) mg/dL, Δ +51.43 %, p = 0.124), lower the maximum speed ratio (MSR) (0.71 ± 0.03, Δ -15.48 %, p = 0.004), but a greater height of the ST-slope (STH) in the ischemic zone on the differentiated ECG (0.65 ± 0.04 mm, Δ +25.00 %, p = 0.022), than those in patients with LVEF ≥55 %. In the STEMI group with LVEF <50 %, slightly higher STH values were noted during the period of maximum elevation of the ST segment on the differentiated ECG (2.51 (1.90; 3.16) mm, Δ +30.05 %, p = 0.060) as compared to the group with LVEF ≥50 %. SA patients with LVEF <60 % had a tendency to higher levels of CRP (0.50 (0.29; 0.67) mg/dL, Δ +51.52 %, p = 0.076) and ET-1 (9.15 (7.00; 11.18) pg/ml, Δ +28.69 %, p = 0.075) in comparison with LVEF ≥60 % group. Patients with SA and a CRP level ≥0.5 mg/dL had higher ET-1 values (10.83 (9.94; 12.64) pg/ml, Δ +58.10 %, p < 0.001), lower values of MSR on the differentiated ECG in the ischemic zone (0.63 (0.52, 0.74) , Δ -41.12 %, p = 0.001) as compared to those in the CRP <0.5 mg/dL group. The negative direction of the T wave and various types of rhythm disturbances in SA patients led to more significant decrease in MSR indicator of the differentiated ECG. Conclusions. Values of LVEF <55 % in CAD, LVEF <50 % in STEMI, LVEF <60 % in SA, CRP ≥0.5 mg/dL in SA are associated with worse indicators of clinical, laboratory and instrumental methods of examination that allow to describe the condition of ischemic myocardium, and the ECG digitalization based on the medical software “Smart-ECG” allows to expand the diagnostic capabilities.

Baseline predictors of final infarct size in patients with ST elevation myocardial infarction undergoing primary PCI

Abstract Background In patients with coronary artery disease, the presence and extent of myocardial scar determined from cardiac magnetic resonance (CMR) imaging have recognized associations with major adverse cardiac events. Therefore, in patients presenting with ST elevation myocardial infarction (STEMI), early prediction of final infarct size (IS) has important prognostic and therapeutic implications. Purpose We sought to determine the predictors of final IS from baseline clinical, laboratory, and CMR imaging variables in patients presenting with STEMI and undergoing successful primary PCI (pPCI). Methods After successful pPCI, 76 STEMI patients underwent baseline (within 48-hours) and 3-months follow-up CMR imaging. The baseline CMR study was used to measure left ventricular (LV) volumes, ejection fraction (EF), and global longitudinal strain (GLS), the latter calculated using feature tracking from cine images. Final IS was measured in the 3-months follow up study using signal intensity quantification by the full width at half maximum method from late gadolinium enhancement images and expressed as a percentage of the total LV mass. Serum ST2 was drawn within 48 hours of STEMI presentation. Maximum values of ECG ST elevation prior to pPCI and serum Troponin I during index hospitalization were measured. Non-collinear baseline variables deemed significantly associated with the final IS on univariable linear regression and captured in all patients were entered into a multivariable model, adjusting for age and sex. Results Mean age was 54.1±10.9 years, 64 patients (78%) being males. Mean LV EF was 43.5±9.8%. Univariable predictors of final IS included hypertension, baseline maximum troponin, ST2, maximum ST elevation, LV volumes and EF, GLS, total angiographic procedure time, the presence of multi-vessel CAD, use of thrombectomy, TIMI flow and myocardial blush grades at baseline and after wiring, and prescription of loop diuretics and potassium-sparing diuretics on discharge (Table 1). A final multivariable linear model was constructed including age, sex, maximum troponin, maximum ST elevation, ST2, LV EF and GLS. In this model, baseline LV EF, maximum troponin, and maximum ST elevation remained independently associated with the final IS. Respective beta coefficients [95% CI] were -0.63 [-1- (-0.26)], 0.22 [0.11-0.33], and 0.90 [0.22-1.58]; p=0.001, <0.001, and 0.01) (Table 2; adjusted R2=0.6, p<0.001). ST2 and GLS were no longer associated with the IS. Conclusion After successful pPCI, baseline LV EF, maximum troponin I, and maximum ST elevation were independent predictors of final IS. These simple markers can identify patients at high risk of final IS who might benefit from advanced therapeutics. Future studies are warranted to confirm the prognostic value of risk scores incorporating these markers. Advanced laboratory (ST2) and imaging (strain) markers were not independently associated with IS.

Experimental and numerical simulation studies of the flow characteristics and temperature field of Fe-based powders in extreme high-speed laser cladding

Extreme high-speed laser cladding technology (EHLA) is widely employed in critical parts manufacturing and repairing due to its high efficiency. The appearance and quality of the cladding layer are directly influenced by the powder flow characteristics and the interaction between powder trajectory and laser beam. In order to elaborate Fe-based powder flow characteristics of the EHLA process, this study established a powder flow model with a ring-shaped nozzle using a transient process bidirectional coupling. The accuracy of the powder flow model was verified using a high-speed camera. The results demonstrated that the error between the simulation results and the real-time images was within 10 %, confirming the validity of the powder flow model. The temperature profiles of laser-powder coupled model indicated that the optimal melting effect of Fe-based powder was achieved at a laser power of 1500 W. Moreover, the maximum elevation angle of the powder flow was mainly influenced by the carrier gas and protective gas flow rate. The experimental and simulation results showed that the optimal process was a protective gas flow rate of 40 L/min and a carrier gas flow rate of 7 L/min.

Identifying ice‐jam flooding events through the application of dendrogeomorphological methods

AbstractIn this research, we explore whether a dendrogeomorphological assessment of tree scarring can accurately summarize past ice‐jam flooding events occurring at a given reach of a river. A sample site was chosen with a history of ice‐jam flooding located in close proximity to a river gauge station. Samples were collected along a 200‐m stretch of riverbank to capture the variation in elevations and possible different ice‐jam flooding events. Disk samples were collected from trees with visual scarring evidence that indicated they had endured a past ice‐jam event. Tree cores from an adjacent stand were collected to create a master chronology for each of the sampled species. Tree disks and cores were analyzed under a microscope using a Velmex stage system, then visually and statistically crossdated using the program COFECHA. Based on the last year of tree growth, years of individual injury events were established. The years of injury event dates were compared against the years of highest instantaneous maximum water elevations from gauged river data. The two data sets correlated, as the years with the highest recorded injury event dates were also the years of highest instantaneous water level elevations. The most common years of injury event dates were directly reflected in the top 5 years of the highest river instantaneous water level elevations. In addition, the year of 2020 had the highest water elevations in the past 27 years, which was again reflected in the dendrogeomorphological data as the injury event year of 2020 was recorded on over 90% of the sampled tree disks. The correlation found between the gauged river data and the dendrogeomorphological data strongly suggests that past ice‐jam flooding event dates can accurately be determined through the analysis of trees in riverbank stretches that have been impacted by ice jams. The relationship of the gauged river data to the dendrogeomorphological data will therefore allow researchers to determine ice‐jam site histories in remote areas where no gauged data exist. The site histories can provide information such as the years or heights that past ice‐jam flooding occurred, which could then be used in ice‐jam flooding hazard assessments.

Assessing the control factors upon glacial valley development in southernmost Patagonia (Fuegian Andes of Argentina)

Research on landscape glacial modelling provides particularly relevant information about the complex connection between climate change and relief evolution. Glacial valleys – the most distinctive landforms in alpine-type settings – were systematically mapped across the Fuegian Andes of Argentina, southernmost Patagonia, and quantitatively investigated in terms of the geoenvironmental agents that controlled their formation. A total of 646 troughs were identified and studied in four sub-areas with contrasting past glacial cover. Our observations demonstrate that longer valleys are also the deeper, less steep (in long profile), more sinuous and lower, and that maximum elevation was the main control of altitudinal range, mean and maximum slope, and minimum depth. Overall, it is considered that valley development was subject to conditioning by pre-glacial topography, geological structure and climatic forcings. Specifically, valley's spatial arrangement indicates that glaciers responsible for their erosion (possibly during the early Pleistocene) adjusted to a fluvial drainage network organized according to a marked structural control, mainly associated with Magallanes-Fagnano and Canal Beagle regional strike-slip systems. The predominance and higher degree of development of southern slope valleys reveal that north-south differential insolation effect was determinant in the Fuegian glaciers' balance during extensive time-lapses in glacial cycles, likely reflecting a scenario of relative aridity and comparatively clear skies. Morning-afternoon contrasts in solar radiation receipt and, specially, humid winds from the west (regional westerlies) would have also produced a moderate eastward bias in valley direction. In the western and central sectors, formerly covered by the Cordillera Darwin Icefield, the surface of Fagnano and Beagle outlet palaeolobes and other major collectors constituted a comparatively high base level for mountain glaciers' incision during full glacial conditions, leading to the creation of profuse, short hanging valleys. In the eastern domain, on the contrary, glaciers appear to have been essentially regulated by the topoclimatic factors, attaining greater dimensions and flowing down to lower altitudes in south- and southeast-facing slopes. Finally, in marginal, lower mountains (away from the main chain axis) ice is thought to have formed only under the most severe glacial episodes in the zone.

Does calibration pose improve scapular kinematic repeatability in functional tasks?

Tracking scapular motion can be challenging. More research is needed to determine the best practices for scapular measurement in multi-planar tasks. The purpose of this study was to compare the repeatability of scapular kinematics during a functional task protocol calculated from different calibration procedures. It was hypothesized that select poses would improve repeatability in specific tasks. The torso, humerus, and scapula were tracked with optical motion capture in two sessions for ten pain-free participants. Scapular calibrations were completed in five poses: neutral, maximum elevation, 90° abduction, hand to contralateral shoulder, and hand to back. Each participant completed eight functional tasks (Comb Hair, Wash Axilla, Tie Apron, Overhead Reach, Side Reach, Forward Transfer, Floor Lift, Overhead Lift). Scapular angles were calculated with five different calibration procedures and extracted at 30° increments of humeral elevation in each task. Mean difference, limits of agreement, intraclass correlations, and minimal detectable change (MDC) were calculated for each task and elevation level. The inclusion of different calibration poses did not markedly improve outcomes over the maximum elevation double calibration for most tasks. Using this calibration procedure, median MDCs were 10.0° for upward rotation, 13.7° for internal rotation, and 9.8° for tilt.

Ancient human colonization explains dung beetle species richness in the Mediterranean and Macaronesian islands

AbstractAimDifferent hypothesis have been proposed to explain differences in species richness among islands. However, few studies have attempted to compare the explanatory power of multiple hypotheses using a large data set. Here, we analyse how different types of predictors (energetic/climatic, environmental heterogeneity, island biogeography and anthropogenic) affect variation in dung beetle species richness on Mediterranean and Macaronesian islands.LocationMediterranean and Macaronesian islands.TaxonDung beetles.MethodsUsing a large data set of islands (n = 147), we extracted the species richness of dung beetles on each island using 362 bibliographic reference sources. We performed GLMs to analyse the relationship between the species richness of dung beetles and 11 explanatory variables (temperature, evapotranspiration, aridity, area, maximum elevation, connection to continent during LGM, geological origin, distance from continent, nearest continent, years since first human colonization and human density) representing four types of causal hypotheses. We also included as a covariate the number of published papers studying dung beetles as a surrogate of the survey/study effort carried out in each island.ResultsGLMs suggest that the years since first human colonization, the number of published papers and island area were the predictors with a higher explanatory capacity. The volcanic character of the islands and the distance from the mainland had some relevance in the case of Scarabaeinae and Geotrupinae, and maximum elevation appeared relevant in the species richness of Scarabaeinae and Aphodiidae. The anthropogenic and island biogeography hypotheses on the variation in species richness were the ones that have the strongest explanatory capacity, regardless of the inclusion of the surrogate of survey effort as a covariate in the models.Main conclusionsThe long history of human movements and agricultural activities has facilitated the colonization of dung beetles and provided trophic resources for their persistence, leading to increased species richness. Thus, the importance of anthropogenic factors in shaping the biodiversity patterns of island biogeography cannot be ignored. These human‐induced influences may play a fundamental role in altering the biogeographic patterns of islands, even overriding the importance of other variables. Consequently, our findings underline the profound impact of historical human actions on islands biodiversity.

Effects of Patch Density and Incoming Sediment on Flow Characteristics and Bed Morphology

This study focuses on the effects of vegetation patch density, bed condition, and incoming sediment on flow structure and bed morphology within and around a patch. The variation in upstream adjustment velocity is not well defined for low-density vegetation patches but decreases with increasing patch density in high-density patches. The length of the upstream adjustment region is greater for high-density vegetation. Incoming sediment causes a reduction in both the steady wake velocity and the length of the steady wake at a low density. The length of the recovery region increases with density when vegetation is sparse, but remains constant in a dense patch. Additionally, the length of the recovery region decreases due to incoming sediment. Turbulent kinetic energy is not affected by the bedform and incoming sediment when reaching its first peak. However, the second maximum of the turbulent kinetic energy increases when the bed is movable. The evolution of bed morphology is closely related to the flow structure and the growth of the von Karman vortex street. Both the rising length and the adjusted length decrease with increasing patch density, while the incoming sediment causes an increase in the adjusted length. Behind the patch wake, the first minimum elevation, maximum elevation, and second minimum elevation decrease as the patch density increases. These values, in turn, increase with the sediment supply upstream of the flume.

EXTREME WAVES IN SHALLOW WATER AND DREDGED CHANNELS FOR DIRECTIONAL SEAS

Extreme wave conditions at coastal structures located offshore of natural coastlines and the zone of wave breaking are influenced by the deepwater wave conditions, the coastal bathymetry between deepwater and the structure, and the ongoing growth, generation and decay of waves across the coastal shelf. At locations where the coastal shelf is relatively flat, the gradually reducing water depths can limit the significant and maximum wave heights and crest elevations that may be encountered. If a coastal structure is located in deeper water than the bathymetry of approaching waves, for example port or navigation structures located in dredged channels or basins, coastal engineers need to consider wave conditions in the shallower approach waters and the transformation and propagation of waves across the dredged area. The directional characteristics of wave spectra in this situation can have a significant impact on extreme wave conditions that occur within the dredged basin. This paper presents insights into extreme wave conditions for gently sloping natural seabed profiles and also within a dredged basin, for directional seas which occur within the direct path of severe storms; for example, tropical cyclones.

Experimental investigation on mitigation of thermal runaway propagation of lithium-ion battery module with flame retardant phase change materials

In the application of lithium-ion battery (LIB) modules, the pivotal factor in ensuring battery safety performance lies in enhancing thermal management effectiveness and adeptly curbing the thermal runaway propagation (TRP). This paper synthesizes the innovative type of high thermal conductivity composite phase change material (CPCM) and flame retardant phase change material (RPCM) with the inclusion of intumescent flame retardant (IFR). The structural and thermal attributes of these phase change materials (PCMs) are meticulously examined. The findings reveal that the RPCM, fortified with 10% SiC and 10% IFR, attains a peak thermal conductivity of 4.022 W/(m·K) and latent heat of 112.9 J/g. Diverse PCMs are then employed to scrutinize the thermal management of single cell and the mitigation of TRP in battery modules. The outcomes of charging and discharging cycles demonstrate that PCM cooling effectively curbs maximum temperature elevation. The most efficient PCMs reduce the maximum temperature by around 7.8 ℃ and 7.4 ℃. The impact of RPCMs and aerogel on curtailing TRP unveils that their amalgamation notably diminishes the risk of TRP and prolongs the propagation time. This research contributes a novel approach by exploring advanced PCMs potential to tackle heat dissipation optimization and TRP suppression for LIB modules simultaneously, and these findings proffer valuable information into enhancing battery operational safety.

Development of a Regional F‐Region Critical Frequency Model for Southern Africa

AbstractA new localized linear regression model, called the SANSA model, is presented. The model provides a forecast of the F‐region critical frequency (foF2) over Grahamstown, South Africa (33.31°S, 26.52°E). The input parameters of this model are the maximum daily solar elevation angle, the F10.7 cm radio flux index and the planetary K index. The output parameter is the forecasted foF2. The historical data‐set consists of ionosonde foF2 observations made in Grahamstown for the period 2010–2019. The historical and predicted data sets used to develop the model are obtained from databases maintained by the South African National Space Agency, the National Aeronautics and Space Administration and the National Oceanic and Atmospheric Administration. The model improves on the results of the Ionospheric Communications Enhanced Profile Analysis and Circuit Prediction Program in terms of the root mean square error skill score metric. The work presented shows that a linear regression model based on the solar elevation angle as well as the F10.7 and planetary K indices can closely approximate observed foF2 magnitudes during quiet and storm times.

Electromyographic activities of glenohumeral joint muscles during shoulder forward flexion with isometric horizontal abduction loading.

Isometric horizontal abduction loading has been applied to improve imbalanced scapular muscle activities during shoulder exercises; however, the effect on glenohumeral joint muscle activity remains unclear. The purpose of this study was to investigate the changes in electromyographic activity of shoulder muscles during forward flexion with isometric horizontal abduction loading in healthy participants. Thirteen healthy men were recruited for this study. Participants performed shoulder forward flexion with isometric horizontal abduction loading using an elastic band (Flex-band condition) and forward flexion without shoulder loading (Normal-flex condition). Muscle activities were evaluated while maintaining shoulder flexion at 60°, 90°, 120°, and 150° (static task) and during active shoulder flexion from 0° to maximum elevation (dynamic task). Surface electrodes were placed on the deltoid, pectoralis major, infraspinatus, and teres minor muscles to measure the activities of the shoulder muscles during each task. The muscle activities during the static task were compared using a 2-way analysis of variance with repeated measures of the 2 factors, loading condition and flexion position, and a paired t test was used for comparisons between the 2 conditions during the dynamic task (significance level set at P<.05). For the static task, the Flex-band condition significantly increased the deltoid middle and posterior activities by 2-15 times and the infraspinatus and teres minor activities by 2-3 times compared with the Normal-flex condition at all positions. In contrast, the Flex-band condition significantly decreased (by about half) the activities of the deltoid anterior (at 120° and 150°) and pectoralis major (at all positions) compared with the Normal-flex condition. For the dynamic task, the Flex-band condition significantly increased the deltoid middle, deltoid posterior, infraspinatus, and teres minor activities by 2-7 times and decreased the deltoid anterior activity by approximately two-thirds. Applying isometric horizontal abduction loading during shoulder forward flexion may be useful in improving the imbalanced muscle activities of the glenohumeral joint, such as excessive activity of the deltoid anterior and pectoralis major and dysfunction of the deltoid middle, deltoid posterior, and shoulder external rotator muscles. Shoulder forward flexion with horizontal abduction loading could be available for exercise in patients who have massive rotator cuff tears or who have undergone rotator cuff repair and shoulder arthroplasty.

Characterization of uncertainty in maximum tidal elevation near Bangladesh coastline due to uncertain sea level rise

AbstractThe Ganges‐Brahmaputra‐Meghna delta is vulnerable to sea level rise from global warming. Based on sea level rise predictions for the year 2100 given in the 6th Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), we examine the effect of uncertainty in sea level rise on maximum tidal elevation statistics at several locations along the Bangladesh coastline using a discretized derived distribution approach. For five IPCC scenarios, the standard deviation in maximum tidal elevation including sea level rise is predicted to increase by between 3% and 61% at three different locations for a 41% increase in the standard deviation of mean sea level rise. By excluding the linear effect of sea level rise, the increase in the standard deviation of maximum tidal elevation is found to vary spatially from 2% to 68% with a 41% increase in the standard deviation of sea level rise.

Fully coupled aero-hydrodynamic modelling of floating offshore wind turbines in nonlinear waves using a direct time-domain approach

In standard operating conditions, a floating offshore wind turbine (FOWT) suffers from the combined action of nonlinear waves and wind. It is important to explore the effect of higher-order hydrodynamic loads induced by the nonlinear waves on its motion response. In this work, a fully coupled aero-hydrodynamic analysis method for FOWT is developed. The hydrodynamic part is based on the nonlinear potential flow theory and the perturbation approach, using a higher-order boundary element method in the time domain. Blade element momentum theory is applied to evaluate the aerodynamic load on the turbine rotor. The mooring system is modelled by the catenary theory. The developed method is verified against the published data of the NREL's 5-MW baseline wind turbine supported by the DeepCwind semi-submersible platform. The verifications are conducted stepwise in the following ways, including hydrodynamic wave excitation load, free-decay response, the load-displacement relationship of the mooring line, the steady-state response of the wind turbine, and fully coupled aero-hydrodynamic interaction. It is found that the nonlinear effect mainly influences the surge motion. The coupled configuration has little effect on the linear wave force and platform displacement but notably impacts the nonlinear wave force and displacement. The FOWT motion is found to be critical in changing the wave field, the maximum wave elevation position around the platform, and the nonlinear wave force acting on the floating platform. The results illustrate that the traditional indirect time-domain method using the Quadratic Transfer Function (QTF) based on assumed response cannot appropriately evaluate the nonlinear wave force of a FOWT in coupled motions. The results also reveal that nonlinear wave hydrodynamics is necessary to understand the motion response of a fully coupled FOWT.

Impact of Varying Transcutaneous Electrical Stimulation Pulse Frequency on Swallow Timing Measures in Healthy Adults.

The impaired swallow timing subsequent to dysphagia or aging can potentially endanger swallowing safety and efficiency. Preliminary evidence has suggested that transcutaneous electrical stimulation (TES) may have the potential to affect swallow timing. However, limited knowledge exists regarding which TES parameters can optimize swallow timing. Pulse frequency is one of the primary TES parameters that can affect the quality of muscle contraction. Yet, no clear information exists regarding how changing pulse frequency impacts the timing of swallowing events. This study aimed to investigate the varying effects of submental TES pulse frequency on swallowing events during and post-15-min TES administration. Twenty-six healthy individuals between the ages of 20 and 54 participated in this study and were assigned to high pulse frequency (HPF) (80 Hz) or low pulse frequency (LPF) (30 Hz) groups. Videofluoroscopic swallowing study (VFSS) was used to record swallowing. Three trials of 10mL pureed mixed with barium sulfate were presented under three different conditions, including pre-TES, during TES, and post-TES, in which measures were taken following 15min of TES delivery. The swallow timing events that were measured in each condition were time to maximum hyoid elevation, time to maximum laryngeal elevation, laryngeal vestibule closure reaction time (LVCrt), laryngeal vestibule closure duration (LVCd), time to maximum pharyngeal constriction, and pharyngoesophageal segment (PES) opening duration. No significant pulse frequency effect was found on any swallow timing measures during or after 15min of TES. Both protocols decreased the duration of some swallowing events during TES including time to maximum hyoid elevation [p < 0.017, ηp2 = 0.185], LVCrt [p < 0.032, ηp2 = 0.158], and time to maximum pharyngeal constriction [p < 0.034, ηp2 = 0.155]. None of the significant TES effects were continued when TES ceased after 15min. Overall, both protocols have comparable immediate effects on shortening the duration of some swallowing events during TES. Future clinical trials should examine whether these physiologic timing changes can lead to safer and more efficient swallows in patients with dysphagia.

Design of an Open Channel for Flood and Gully Erosion Control: A Case Study of Amakohia-Uratta in Imo State, Nigeria

Flooding and gully erosion constitute a major problem associated with urbanization in the underlying watershed of an area. In this study, a trapezoidal channel hydraulic system was designed for flood and erosion control in Amakohia-Uratta, Owerri North, Imo state, Nigeria. A topographical survey of the study area was done. The result shows that the maximum elevation is 81.03 m, the minimum elevation is 78.21 m, the bed slope of the area is 0.02%, the area of the watershed is 1.061ha, and the maximum length of flow is 140m. Also, the results from the hydrological analysis using the rational method indicated that the rainfall intensity of 10 years duration was 105.3 mm/h with a peak discharge Qp of 0.17 m3/s, causing the flood and erosion, while the channel design capacity (discharge) Qd is 0.17 m3/s, calculated using trial and error methods. Finally, design parameters for the trapezoidal open channel were calculated. The result indicated that the channel width is 0.3 m, the design depth is 0.5 m, the freeboard is 0.1m, the total channel depth is 0.6m, the top width of the channel is 2.1 m and the side slope is 1.5:1. In all the design is appropriate to capture, carry and discharge the peak runoff to Nworie River a natural outlet.

Debris Flow Classification and Risk Assessment Based on Combination Weighting Method and Cluster Analysis: A Case Study of Debris Flow Clusters in Longmenshan Town, Pengzhou, China

Debris flows can damage infrastructure and threaten human life and property safety, especially in tourist attractions. Therefore, it is crucial to classify and evaluate the risk of debris flows. This article takes 14 debris flows in Longmenshan Town, Pengzhou, Sichuan, China, as the research object. Based on on-site geological surveys, combined with drone images and multiple remote sensing images, the essential characteristics of each debris flow are comprehensively determined. A total of nine factors are used as the primary indicators affecting the risk of debris flow: drainage density, roundness, the average gradient of the main channel, maximum elevation difference, bending coefficient of the main channel, the loose-material supply length ratio, vegetation area ratio, population density, and loose-material volume of unit area. The subjective weights of each indicator are obtained using the Analytic Hierarchy Process, while the objective weights are obtained using the CRITIC method. Based on this, the distance function is introduced to couple the subjective and objective weights, determine each indicator’s combined weights, and obtain the integrated evaluation score values of different debris flow hazards. Considering the integrated evaluation score of debris flow, cluster analysis was used to classify 14 debris flows and cluster effectiveness indicators were introduced to determine the effectiveness of debris flow classification. A quantitative standard for the risk of debris flow within the study area was proposed, and finally, a risk assessment of debris flow in the study area was made. Comparing the results of this paper with the gray correlation method, the coupled synergistic method, and the geological field survey results, proves that the proposed method is feasible and provides a reasonable scientific basis for the study of the hazard assessment of regional debris flow clusters and other related issues within the scope of the Jianjiang River basin and other areas.