Area Threshold Research Articles

Non‐linear thresholds in the effect of area on three dimensions of diversity of herpetofauna in the West Indies

AbstractAimThe small‐island effect (SIE) describes an anomalous feature of the species–area relationship (SAR) on smaller compared to larger islands. However, previous studies on SIEs mainly focused on taxonomic diversity and overlooked phylogenetic and functional diversity. In this study, we explored SIEs in three dimensions of diversity. We expect to see the non‐linear thresholds in the effect of area on three dimensions of diversity as well as on community structures, because the dominant assembly processes vary across spatial scales.LocationThe West Indies.TaxonHerpetofauna.MethodsWe derived data on the presence/absence of 199 amphibian species on 163 islands and 614 reptile species on 748 islands in the West Indies. We built a species‐level phylogenetic tree and a species‐level functional tree to estimate six taxonomic, phylogenetic and functional diversity indices. Four community metrics on behalf of the phylogenetic and functional community structure of each island were calculated using a null modelling framework and was quantified using the standardized effect size (SES). We explored the non‐linear thresholds in the effect of area for each of the diversity indices and SES values of community metrics by comparing six piecewise regression models with a linear regression model and a null model.ResultsWe found evidence of SIEs in four diversity indices representing all three dimensions of diversity. Besides, area thresholds were also found in the phylogenetic and functional community structure for both amphibians and reptiles. Random extinction, competitive exclusion and adaptive radiation are the dominant processes structuring reptile communities on small, intermediate and large islands respectively.Main ConclusionsTo conduct a comprehensive biodiversity conservation plan concerning taxonomic, phylogenetic and functional diversity, we suggest it is necessary to explore the SIEs in various diversity indices representing all three dimensions of diversity and apply the lowest threshold value to make management strategies.

Design Principles for Balancing Lipophilicity and Permeability in beyond Rule of 5 Space.

An ab initio conformational analysis of oral beyond Rule of 5 (bRo5) drugs was complemented with measured permeability and logP(octanol) to derive design principles conferring oral bioavailability. 3D polar surface area (PSA) thresholds for oral bRo5 drugs coincided with those reported for Ro5 space. The majority of oral bRo5 drugs exceeded the Ro5 logP threshold of 5, reflecting a bias for permeability. Above 500 Da molecular weight (MW), oral drugs and highly permeable Novartis compounds occupy a narrow polarity range (topological or TPSA/MW) of 0.1-0.3 Å2 /Da, whose upper half coincides with the lower 90 percentiles of the Novartis logP set. This TPSA/MW range and 3D PSA below 100 Å2 define the "Rule of ~1 /₅" for balancing lipophilicity and permeability. Neutral TPSA, defined as TPSA minus 3D PSA occurs independent of conformation, intramolecular hydrogen bonds (IMHB) and MW, suggesting it is an intrinsic molecular property. Neutral TPSA increased in the lead optimization (LO) campaigns of three first in class de novo designed bRo5 drugs and may be a useful design parameter in bRo5 space.

Geometric overlapping coefficients for calculating the required emitters per plant in drip irrigation

The designer of irrigation systems must consider a complex combination of emitter type, emitter uniformity, hydraulics, topography, desired water distribution, crop salt tolerance, water requirements, water quality, fertilizer injection, soil salinity, cultural practices, and other site-specific conditions. In contrast to the approaches applied for the hydraulic design of irrigation installations, there is not a clear, general and consolidated design criterion for calculating the number required emitters per plant. In most cases, given the wide spectrum of possible scenarios, only guideline recommendations can be found, and the final decision is often based on the subjective experience of the designer or grower. This paper aims at revising, clarifying and refining the existing published guidelines and methodologies for estimating the required emitters per plant in drip irrigation, focussing on the Montalvo approach. The agronomic design should satisfy, among others, two specific conditions: (i) the emitters should wet at least a minimum threshold of the soil area (or volume) corresponding to the plant for ensuring a proper development of the roots; (ii) overlapping between emitter bulbs is required for merging wetted volumes and avoiding salt concentration near the root zone. Relying on this basis, a thorough theoretical geometric analysis of the overlapping between wet bulbs of contiguous emitters is carried out. As a result, Montalvo's overlapping coefficients are deduced here. This author assumes an identical net wetted area for all emitters in the laterals, but it can be stated that the overlapping areas between emitters differ in extreme emitters and interior emitters, as well as in configurations with one lateral per plant row and two laterals per plant row. Therefore, this study proposes new formulations for the computation of the overlapping coefficient, which need to incorporate the number of emitters as an additional variable, as well as to distinguish between the presence of one or two laterals per plant row, and between grouped and non-grouped emitters. In one lateral per plant row, the original overlapping coefficient underestimates the net wetted area by one emitter and thus overestimates the theoretical number of required emitters. In the case of two laterals per plant row, the original overlapping coefficient overestimates the net wetted area in the interior emitters, and thus underestimates the theoretical number of required emitters per plant. The presented formulations are applied in different practical examples covering a wide range of scenarios. The results allow a general overview of the influence of the soil type, the emitter flow rate, and the selected overlapping ratio in the number of required emitters per plant. The revision of guidelines and methods presented here, complemented with other experimental results and models of soil water dynamics under drip irrigation, might contribute to a better decision making of designers and field engineers.

Meteorological drought migration characteristics based on an improved spatiotemporal structure approach in the Loess Plateau of China

The development of drought has spatial and temporal synchronization. Previous studies usually explore the spatial and temporal evolution of drought separately. Moreover, existing approaches are based on a fixed overlapping area and do not consider the variable drought cluster area during development. This study proposes an improved and simple approach to derive dynamic overlapping area threshold for 3-dimensional droughts extraction. Based on the one monthly Nonparametric Standardized Precipitation Index (NSPI), this improved approach was applied for investigating the migration characteristics of meteorological drought events in the Loess Plateau of China. Then, Random Forest and Extreme Gradient Boosting model with Shapley additive explanation values were used to quantify the importance of driving factors on the dynamics of drought characteristics. The results showed that: (1) the improved approach has a better performance on identifying prolonged droughts than the method using a fixed overlap area threshold; (2) spatially, meteorological drought events with high severity (DS), long duration (DD), large effected area (DA) and fast migration velocity (DV) mainly occur in the central region; (3) temporally, droughts are expected to aggravate with significantly increased DS and DA which are mainly caused by increased temperature and vegetation; and (4) meteorological droughts have a preferred westward migration direction and three dominant migration paths, which are crucial for local drought prevention and control. The findings of this study provide new perspectives on drought migration characteristics, which are important for the exploration of drought-driven mechanisms, risk assessment and future prediction.

Infrared Ship Target Detection Based on Dual Channel Segmentation Combined with Multiple Features

In infrared images of the sea surface, apart from the complex background of the sea surface, there are often sky and island backgrounds. The disturbances caused by sea wind and the reflection of intense sunlight on the sea surface increase the complexity of the background, which seriously hinders the detection of targets. To achieve the detection of dark-polarity ship targets in such environments, a dual-channel threshold segmentation method based on local low-gray region detection and geometric features judgment is proposed in this paper. In one channel, adaptive threshold segmentation is performed on the low-gray regions of the acquired image and combined with geometric features to obtain a finer segmentation result. In the other channel, adaptive segmentation is performed on the preprocessed image, and potential backgrounds that may be finely segmented as targets are filtered out based on an area threshold. Finally, the results of the two channels are multiplied and fused to obtain an accurate segmentation result. Experimental results demonstrate that the proposed algorithm outperforms the comparison algorithm in subjective and objective evaluations. The proposed algorithm in this paper not only achieves a low false alarm rate but also exhibits a higher detection rate, and the average detection rate in the test sequence surpasses 95%.

Optimizing slope unit-based landslide susceptibility mapping using the priority-flood flow direction algorithm

Regional-scale landslide susceptibility assessments are challenging and have recently captured the attention of scientists and technicians. A slope unit is a typical map unit that enhances the readability of landslide susceptibility maps (LSMs) by reducing ridge effects. Slope units are commonly obtained via the subbasin division (SBD) method from a digital elevation model (DEM) containing sink features, such as depressions, pits and flats. The SBD method addresses the depression problem by filling features but subsequently faces unresolved problems with parallel slope-unit boundaries. The main objective of this study was to introduce the priority-flood flow direction (PFD) algorithm to exploit flow information for depressions and compare PFD-improved slope units to SBD-based slope units in corresponding LSMs. An LSM case study was generated using an artificial neural network in Yan’an city, China, where loess ridge and hill landforms are developed. Data for a total of 447 landslides were obtained from historical records and field surveys to construct a landslide inventory map, where 313 landslides (70%) and 134 landslides (30%) were used for training and validation, respectively. Then, 9 conditioning factors related to landslides were prepared as inputs to generate six LSMs by combining two map units and three catchment area thresholds. These factors included elevation, slope, river distance, road distance, rainfall, normalized difference vegetation index (NDVI), aspect, land use and lithology. Finally, the resulting LSMs were validated and compared between the PFD and SBD methods using the precision, recall, accuracy, F1 score, success rate and prediction rate based on receiver operating characteristic (ROC) and cumulative landslide occurrence (CLO) curves. The results showed that the improved slope units produced no parallel boundaries, and the environment-factor layers generated based on these slope units prevented the generation of parallel factor-subclass boundaries, thus reducing striped distributions of factors and optimizing patterns in the LSMs. The PFD-improved LSM yielded ROC-based success rates ranging from 0.8849 to 0.8901, which were better than those obtained for the SBD-based LSM, at 0.8779–0.8823. The prediction rate revealed that the PFD-improved slope units were more suitable for large regions, as they provide more stable performance than the SBD-based slope units at large scales. The PFD algorithm resolved the problem of parallel boundaries and optimized LSM patterns, resulting in enhanced performance over the SBD method in large-scale research. The study results could be useful for local government management and land use planning in large regions.

Effect of soil spatial aggregation caused by the calculation unit division on runoff and sediment load simulation in the SWAT model

Distributed hydrological model divides watersheds into distinct calculation units to simulate hydrological processes. Within the model, different calculation unit division schemes induce input elements, such as soil and land use, to certain degrees of generalization, thus affecting the simulation result. Analyzing the effect of the calculation unit division on the simulation result is an important methodology to reduce uncertainty and improve the simulation accuracy of the model. Previous researchers have focused on the comprehensive effect of underlying surface generalization (such as soil, land use, and terrain generalization) caused by the calculation unit division on the simulation results, while it did not separate the effect of the generalization of the individual input factor on the simulation result. In this paper, the Dongjiang headwater region in southern China was selected as the study area. The single type of land use and slope were input into the Soil and Water Assessment Tool (SWAT) model to fix the effects of land use and terrain caused by calculation unit division on the simulation results. Eleven calculation unit division schemes were used to analyze the impact of soil spatial aggregation on runoff and sediment load simulations. The calculation unit division schemes included 11 sub-watershed division schemes and their hydrological response unit (HRU) thresholds were set at 8 %. The drainage area thresholds of the 11 sub-watershed division schemes were 30 ha, 60 ha, 120 ha, 240 ha, 480 ha, 1000 ha, 1600 ha, 2200 ha, 2800 ha, 3400 ha and 4000 ha. The results demonstrated that the soil spatial distribution showed an obvious aggregation with an increase in the drainage area threshold in the SWAT model. Of these, the Krasnozem soil type which covers the largest area in the watershed, increased significantly with an increase in the drainage area threshold. However, the areas of all the other soil types decreased significantly. The Lioth soil type covers the smallest area in the watershed decreased and even disappeared when the threshold in the SWAT model was greater than 1000 ha. Furthermore, soil spatial aggregation caused a significant increase in the annual runoff and sediment load (P < 0.05), with the sediment load (Re = 29.78 %) increasing at a greater rate compared to runoff (Re = 1.74 %). Increased soil aggregation significantly increased the sediment loads in the maximum 1-day, the continuous maximum 5-day, the continuous maximum 7-day, and the sediment load in flood processes (P < 0.001). Refining the calculation unit division scheme will cause a significant increase in the number of calculation units. Due to the computer processing power limitations, we cannot further refine the calculation unit division scheme. Based on our current operational calculation unit division scheme, we did not identify the optimal division scheme in the study region. These results can provide reference information for future research into hydrological model uncertainty and can improve the SWAT model simulation accuracy.

Gas chromatography-flame ionization detector for sweat based COVID-19 screening

Simple approach for rapid screening of corona virus disease 2019 (COVID-19) has been developed. This applied gas chromatography-flame ionization detector (GC-FID) analyzing the potential compound marker in sweat samples obtained from COVID-19 positive and negative volunteers in Bangkok, Thailand. The samples were collected by using cotton rods for 15 min, heated at 90 °C for 5 min, and the volatile compounds in the headspace (HS) were injected (5.00 mL) at 150 °C and separated within 13.7 min. The marker peak was tentatively identified as p-cymene by the authentic standard injection and comparison with the GC-mass spectrometry (GC-MS) and comprehensive two-dimensional GC (GC × GC)-MS analysis. Possible mechanisms for the presence of p-cymene were proposed. The marker peak area thresholds were then varied and optimized via construction of the receiver operating characteristic (ROC) curve. With the optimum threshold, the established method offered the accuracy, sensitivity and specificity of 96 %. This method was insignificantly affected (p-value >0.05) by genders, body mass indices, ages, and use of deodorants as well as the p-cymene containing food. However, the performance could be affected by the population with personal hygiene or experiencing the microbiomes producing p-cymene.

Method for high-plex analysis of immune cells in human skin using the GeoMx system.

Specific T cell populations in the skin have been demonstrated as important disease drivers in several dermatoses. Due to the unique skin architecture, these cells are not grouped together in structures but dispersedly spread out throughout the epidermis. Following tissue disruption and isolation, only about 10% of skin T cells are recovered and any in vitro expansion may alter their bona fide phenotype. The Nanostring GeoMx system was developed to address cellular phenotype and protein expression in a tissue spatial context. To do so, regions of interest (ROI) must exceed a certain area threshold (usually 100 μm in diameter) to generate a sufficient signal-to-noise ratio. Here, we present an approach that allows for the pooling of numerous smaller ROIs within the skin, enabling T cell and melanocyte phenotyping. Skin samples from healthy individuals and vitiligo patients were analysed using the GeoMx system and several immune profiling panels. A sufficient signal-to-noise ratio was achieved by pooling smaller ROIs and analysing them as a single group. While this prevents spatial analysis, this method allows for detailed analysis of cells as a population in the context of their physiological environment, making it possible to investigate in situ phenotype of rare cells in different tissue compartments.

The dose response of erythemal area and intensity on the unprotected skin fits well to a logistic 3P model in SPF tests of a Chinese population, which has the potential to improve the precision and consistency of minimal erythema dose determination.

The current ISO guidelines for minimal erythema dose (MED) determination require assessment of erythema area of UV-irradiated skin sites. However, this parameter has not been adequately quantified in daily practice. The aims of this study were to investigate the dose response on the unprotected skin sites by quantifying the erythema area and intensity and to show the potential for improving the precision and consistency of MEDu determination by developing predictive models. Standard radiation tests were conducted on the back of 31 healthy Chinese volunteers and the MEDu site of each subject was clinically determined by dermatologists. Images of test sites were captured 24 h after radiation, and the erythema area (%EA) and intensity (∆a*) were measured by image analysis. The data were fitted to a logistic 3P function to obtain dose-response curves, and a set of logit (inverse-logistic) models were then derived. An erythema area threshold of %EA = 52% was established to predict MEDu based on the clinical endpoints defined by ISO 24444:2019. Analysis of the clinically determined MEDu sites revealed wide ranges of %EA (62.3 ± 15% SD) and ∆a* (2.96 ± 0.92 SD). The dose response fitted well to a logistic 3P model (mean R2 = 0.965 and 0.975 for %EA and ∆a*, respectively). Applying the area threshold, values of MEDu were determined by the logit model for the test population, which significantly improved the consistency of MEDu determination (52 ± 0% SD and 2.73 ± 0.61 SD for %EA and ∆a*, respectively). This study demonstrated that the dose response of UV-induced erythema can be quantified and modeled once the erythema area and intensity are measured. The results of this study show the potential to improve the precision and consistency of MEDu determination in an SPF test. The similar potential in photodermatological, therapeutic, and diagnostic applications was also implied.

A Robust Channel Head Extraction Method Based on High‐Resolution Topographic Convergence, Suitable for Both Slowly and Fastly Eroding Landscapes

AbstractChannel networks exert a key control on drainage basins shape and dynamics, including the transfer of water and sediments throughout basins, and thus hydrosedimentary hazards. Landscape dissection by channels results from the competition between hillslope processes and channelized erosion processes such as overland flow or debris flows. In contrast to fluvial channelization, the transition from hillslopes to colluvial channels remains understudied, and high‐resolution LiDAR DEMs open new perspectives for the extensive extraction of channel heads. Several channel extraction methods exist but none is yet robust on fast eroding landscapes. Here we develop the CO2CHAIN method which identifies the hillslope to channel transition in drainage basins based on relative changes of local and upstream measures of flow convergence. We calibrate CO2CHAIN by fitting its results to channel head mapping made by geomorphologists in four contrasted basins in the United States and France with moderate to high erosion rates. Compared to two state‐of‐the‐art channel extraction methods, it fits best the experts' mapping in terms of average characteristics and variability without needing to be recalibrated and does not have to implement a drainage area threshold although it imposes a length scale threshold. This allows to revisit studies on channelization that have not yet included high erosion rate basins.

Quantitative Evaluation of the Influence of Posterior Malleolus Fracture and Fixation on the Rotational Stability of the Ankle

BackgroundThis study aimed to analyze quantitative correlation between the posterior malleolus fracture and fixation and the rotational stability of the ankle and to explore supplementary surgical indications for posterior malleolus fracture.MethodsTwenty fresh frozen cadaver specimens were selected and dissected. Based on the tibial insertion of the ligament complex, the model for the supination external rotation stage 3 ankle fracture with a posterior malleolar fragment and syndesmosis diastasis was created. The area threshold of the posterior tibial insertion of posterior malleolus fracture was biomechanically assessed and the difference of the antirotating ability stiffness of the ankle between simple posterior malleolus fixation and simple syndesmotic fixation was analyzed statistically.ResultsThe tibial insertion of posterior inferior tibiofibular ligament and inferior transverse tibiofibular ligament complex was relatively broad, and its width decreased as the distance from the joint line increased. Biomechanical analysis showed that: the threshold of posterior area of posterior malleolus fracture was 1/4S; posterior malleolus fixation provided better rotational stability than syndesmotic fixation (P < 0.01).ConclusionThe surgical indications for posterior malleolus fracture should consider simultaneously the restoration of the axial and rotational stability of the ankle. Simple posterior malleolus fracture fixation is recommended when the syndesmosis is unstable and the area ratio of posterior tibial insertion of posterior malleolus fracture is greater than or equal to 1/4. Syndesmotic fixation is proposed to restore and maintain the rotational stability of the ankle when the syndesmosis is unstable and the area ratio is less than 1/4. Regardless of the area ratio, the surgical indication only depends on the impact of the posterior malleolus fracture on the axial stability of tibiotalar joint, the involved articular surface area, and the displacement degree of posterior malleolus fragment, when the syndesmosis is stable.

P77 Deucravacitinib, an oral selective allosteric tyrosine kinase 2 inhibitor, vs. placebo and apremilast in moderate-to-severe plaque psoriasis: achievement of absolute Psoriasis Area and Severity Index thresholds in two phase III trials

Abstract Deucravacitinib, an oral selective allosteric tyrosine kinase 2 inhibitor, is approved in the USA and several other countries and is under review by the European Medicines Agency and other health authorities, for the treatment of moderate-to-severe plaque psoriasis. The efficacy and safety results for deucravacitinib in the phase III, 52-week, double-blind POETYK PSO-1 (NCT03624127) and PSO-2 (NCT03611751) trials in patients with moderate-to-severe plaque psoriasis have been published (Armstrong AW, Gooderham M, Warren RB et al. Deucravacitinib vs. placebo and apremilast in moderate to severe plaque psoriasis: efficacy and safety results from the 52-week, randomized, double-blinded, placebo-controlled phase 3 POETYK PSO-1 trial. J Am Acad Dermatol 2023; 88:29–39; Strober B, Thaçi D, Sofen H et al. Deucravacitinib vs. placebo and apremilast in moderate to severe plaque psoriasis: efficacy and safety results from the 52-week, randomized, double-blinded, phase 3 Program fOr Evaluation of TYK2 inhibitor psoriasis second trial. J Am Acad Dermatol 2023; 88:40–51). Additional efficacy outcomes using Psoriasis Area and Severity Index (PASI) measures were assessed. Patients were randomized 2 : 1 : 1 to oral deucravacitinib 6 mg once daily, placebo or apremilast 30 mg twice daily, with treatment switches at weeks 16 and 24 per study designs. Mean change from baseline PASI through to week 52, achievement of absolute PASI thresholds ≤ 3 and ≤ 4 at weeks 16 and 24 and proportions of patients treated continuously with deucravacitinib from day 1 who achieved absolute PASI thresholds ≤ 1, ≤ 2, ≤ 3, ≤ 4 and ≤ 5 at week 52 were determined. Mean baseline PASI was similar across groups in PSO-1 and PSO-2 (deucravacitinib, n = 332 and n = 511, respectively; placebo, n = 166 and n = 255; apremilast, n = 168 and n = 254). Mean change from baseline PASI (baseline mean 21.8) at peak efficacy at week 24 was −16.9 for PSO-1 patients treated continuously with deucravacitinib from day 1; decreases were maintained at week 52 (−17.1). At week 16, significantly higher proportions of deucravacitinib-treated patients vs. placebo and apremilast achieved absolute PASI thresholds ≤ 3 [PSO-1: 42.2%, 7.2% and 24.4%, respectively (P &amp;lt; 0.001 vs. placebo and apremilast); PSO-2: 40.9%, 6.7% and 29.5%, respectively (P &amp;lt; 0.001 vs. placebo and P = 0.002 vs. apremilast)] and ≤ 4 [PSO-1: 55.4%, 11.4% and 31.0%, respectively (P &amp;lt; 0.001 vs. placebo and apremilast); PSO-2: 49.5%, 9.4% and 37.4%, respectively (P &amp;lt; 0.001 vs. placebo and P = 0.001 vs. apremilast)]. Results were maintained for deucravacitinib vs. apremilast at week 24 (P &amp;lt; 0.001). Deucravacitinib patients treated continuously from day 1 achieved high rates of absolute PASI thresholds at week 52 in PSO-1 and PSO-2 (≤ 1, 31.3% and 23.4%, respectively; ≤ 2, 45.5% and 34.7%, respectively; ≤ 3, 54.5% and 44.0%, respectively; ≤ 4, 61.4% and 52.9%, respectively; ≤ 5, 66.0% and 59.5%, respectively). Patients with moderate-to-severe plaque psoriasis who received deucravacitinib achieved clinically meaningful absolute PASI outcomes superior to placebo and apremilast and showed good maintenance of these measures through to week 52. AcknowledgmentsWriting and editorial assistance was provided by Nick Cianciola PhD, CMPP, of Peloton Advantage, LLC, an OPEN Health company, funded by Bristol Myers Squibb. Funding sourcesThis study was sponsored by Bristol Myers Squibb.

Spatial Inequity of Transit and Automobile Access Gap across America for Underserved Population

This study examines the correlates of the Modal Access Gap (MAG) between transit and automobile to employment opportunities in the 45 most populated American metropolitan areas by testing spatial lag regression models and employing the bivariate local indicator of spatial autocorrelation (BiLISA) at the census block group geographical level. Four findings are discerned. First, MAG is positive regardless of the metropolitan area and travel-time threshold and ranges from 0.22 to 0.98. This indicates transit trails automobile in offering access to employment opportunities. Second, millennials and carless households tend to reside in areas with a narrower MAG, while people with disabilities reside in areas with a wider MAG. Third, areas with a high share of carless households and relatively low transit access to employment opportunities are primarily clustered in the suburbs and exurbs of American metropolitan areas. Fourth, the MAG disproportionately affects socially vulnerable populations, including the elderly, people with disabilities, low-income households, Hispanics, and African Americans. Compared with the national average, modal access inequity is prevalent for the elderly in 27, for people with disabilities in 22, for low-income households in 17, for Hispanics in 14, and for African Americans in 12 metropolitan areas. This research is a necessary step forward for instilling social equity into transport planning strategies in parallel with governmental efforts.

Runoff Simulation under the Effects of the Modified Soil Water Assessment Tool (SWAT) Model in the Jiyun River Basin

Few studies have been conducted to simulate watersheds with insufficient meteorological and hydrological information. The Jiyun River watershed was selected as the study area. A suitable catchment area threshold was determined by combining the river network density method with the Soil and Water Assessment Tool (SWAT) models, which was driven using the CMADS dataset (China Meteorological Assimilation Driving Datasets for the SWAT model). Monthly runoff simulations were conducted for the basin from 2010 to 2014, and the calibration and validation of model parameters were completed with observed data. The results showed that the final expression for the density of the river network in the Jiyun River basin as a function of density (y) and the catchment area threshold (x) was obtained as y = 926.782x−0.47717. The “inflection point” of the exponential function was the optimal catchment area threshold. The catchment area threshold had an upper and lower limit of the applicable range and was related to the percentage of the total basin area. The simulation results would be affected if the threshold values were outside the suitable scope. When the catchment area was 1.42% of the entire watershed area, increasing the threshold value had less effect on the runoff simulation results; decreasing the threshold value would cause the simulation results to be unstable. When the catchment area reached 1.42% to 2.33% of the total watershed area, the simulation results were in good agreement with the observed values; the coefficient of determination (R2) and Nash–Sutcliffe efficiency coefficient (NSE) were more significant than 0.79 and 0.78 for the calibration periods evaluation index. Both were greater than 0.77 and 0.76 for the validation period, which met the evaluation requirements of the model. The results showed that the CMADS-driven SWAT model applied to the runoff simulation and the river network density method adoption to determine the catchment area threshold provided a theoretical basis for a reasonable sub-basin division in the Jiyun River basin.

A Modified Bypass Circuit for Improved Reliability of PV Module Validated With Real-Time Data

Solar Power is a promising way of electricity generation but it comes with a drawback of low conversion efficiency which is caused by several factors, the most prominent being partial shading. Partial shading leads to mismatch of PV cells, resulting in formation of hot spot. This leads to power dissipation and physical damage to PV cells. Consequently, panel’s credibility is called into question. A bypass diode reduces the amount of power dissipated by a shaded cell, but it doesn’t entirely prevent hot spot formation. Moreover, bypass diode doesn’t bypass every small shade as it has a shaded area threshold at and above which it begins to bypass the shaded module. Whereas, the rise in temperature may also be triggered even by a small shaded area, like the area of falling leaves, which further creates reliability issues. A few hot spot mitigation strategies have been devised; however, it still has room for improvement. This paper presents a modified bypass circuit arrangement for reliability enhancement of PV systems and it is evaluated for a 3×1 PV string. A comparative analysis with bypass diode is carried out in an experimental study. The efficacy of the proposed methodology is verified based on four performance metrics, namely reverse voltage, power loss under partial shading, the sensitivity of the bypass circuit, and the temperature of the hot spotted module. The proposed technique ensures sensitivity enhancement of the bypass circuit towards shade effect; thus, enhancing the reliability of PV system.

Visualization of the relationship between electrogustometry and whole mouth test using multidimensional scaling

Interpreting the relationship between different taste function tests of different stimuli, such as chemical and electrical stimulation, is still poorly understood. This study aims to analyze visually as well as quantitatively how to interpret the relationship of results between taste function tests using different stimuli. Patients who underwent the whole mouth test and Electrogustometry (EGM) at a tertiary medical center between August 2018 and December 2018 were reviewed retrospectively with electronic medical records. Of the 110 patients, a total of 86 adults who self-reported that their taste function was normal through a questionnaire were enrolled. EGM measured the thresholds of the chorda tympani (CT) and glossopharyngeal nerve (GL) area of the tongue. The whole mouth test measured detection and recognition thresholds for sweet, salty, bitter, sour, and umami taste. Statistical analyses of Pearson’s, Spearman’s rank and polyserial correlation and multidimensional scaling (MDS) was performed. The EGM threshold for the average value of both CT regions and the recognition threshold of the whole mouth test were significantly correlated in sweet, salty, bitter, and sour taste (r = 0.244–0.398, P < 0.05), and the detection threshold was correlated only significant in sweet (r = 0.360, P = 0.007). In the MDS analysis results, the three-dimensional (D) solution was chosen over the 2-D solution because of the lower stress. Detection-, recognition threshold of whole mouth test and EGM thresholds of CT and GL area, those were standardized by Z-score, formed well-distinguished sections in the MDS analyses. The EGM threshold of the CT area was closer to the detection and recognition thresholds than the EGM threshold of the GL area. In general, the EGM threshold was closer to the recognition threshold than the detection threshold for each taste. Overall, visualization of the relationship of whole mouth test and EGM by MDS was in good agreement with quantitative analysis. EGM and whole mouth test seem to reflect different aspects of taste. However, when interpreting the EGM results, the EGM threshold of the CT area will show more similarity to the recognition threshold than the detection threshold for the whole mouth test.

Detection and Monitoring of Woody Vegetation Landscape Features Using Periodic Aerial Photography

Woody vegetation landscape features, such as hedges, tree patches, and riparian vegetation, are important elements of landscape and biotic diversity. For the reason that biodiversity loss is one of the major ecological problems in the EU, it is necessary to establish efficient workflows for the registration and monitoring of woody vegetation landscape features. In the paper, we propose and evaluate a methodology for automated detection of changes in woody vegetation landscape features from a digital orthophoto (DOP). We demonstrate its ability to capture most of the actual changes in the field and thereby provide valuable support for more efficient maintenance of landscape feature layers, which is important for the shaping of future environmental policies. While the most reliable source for vegetation cover mapping is a combination of LiDAR and high-resolution imagery, it can be prohibitively expensive for continuous updates. The DOP from cyclic aerial photography presents an alternative source of up-to-date information for tracking woody vegetation landscape features in-between LiDAR recordings. The proposed methodology uses a segmentation neural network, which is trained with the latest DOP against the last known ground truth as the target. The output is a layer of detected changes, which are validated by the user before being used to update the woody vegetation landscape feature layer. The methodology was tested using the data of a typical traditional Central European cultural landscape, Goričko, in north-eastern Slovenia. The achieved F1 of per-pixel segmentation was 83.5% and 77.1% for two- and five-year differences between the LiDAR-based reference and the DOP, respectively. The validation of the proposed changes at a minimum area threshold of 100 m2 and a minimum area percentage threshold of 20% showed that the model achieved recall close to 90%.

Spark Computing Framework for Pet Medical Information Management System in Pet Healthcare

In recent years, the role of big data technology in various industries has become increasingly prominent. With the rise of the pet trend, the pet medical industry has been developing rapidly. However, the current application of big data in the pet medical industry is single and elementary. This study aims to improve the current situation of big data technology in the pet medical industry and build a pet medical information management system supported by Spark computing framework, HDFS, and HBase. This study uses descriptive research method and comparative analysis method to prove that big data analysis based on Spark framework can greatly improve the efficiency of treatment and reduce the time cost. The information management system based on Spark framework can realize the rapid storage and calculation of massive data, reduce the technical threshold of data application area in pet medical industry, and help to promote the accelerated development of big data industry and pet medical industry.

Refinement of voltage-based atrial scar assessment using pacing thresholds and local impedance

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Boston Scientific Background Common cut-offs for dense scar and ‘low-voltage areas’ on atrial 3D electroanatomical mapping are 0.05mV and 0.50mV respectively. These are not physiologically validated and may not fully represent underlying scar compared with unipolar readings or the novel parameter local impedance (LI). Objectives Investigate the relationship of bipolar voltage, unipolar voltage and LI with pacing threshold (PT). Establish cut-offs for electrically inert (EI), partially active (PA) and electrically active (EA) atrial tissue based upon pacing capture. Methods Patients undergoing AF ablation were recruited. 3D electroanatomical maps were created. PTs were assessed using the MiFi and Stablepoint (SP) ablation catheters between the tip and first ring electrodes. PTs were assessed with a 2ms pulse duration commencing at 5mA and moved up or down accordingly. LI was referenced against a blood pool reading (LIr). EI sites were defined as no pacing capture, PA capture between 5-20mA and EA less than 5mA. Results 292 PTs and LI readings were recorded in 40 patients (Male: 21/40; Age: 66.7 ± 8.8; Paroxysmal AF: 10, Persistent AF: 30, De novo 21, Redo 19). A weak correlation exists between SR voltages and PT (Spearman's Rho - Bipolar: -0.35, Unipolar: -0.26, both p &amp;lt;0.0005). Weak correlations exist between LI and PT, (Spearman's Rho - MiFi = -0.35, SP = - 0.33, both p &amp;lt; 0.0005), but moderate-strong correlations exists between LIr and PT (Rho - MiFi = -0.52, SP = -0.57, both p &amp;lt;0.0005, [Figure 1]). For the EI-PA cut-off, the ability to distinguish capture / no capture for bipolar voltages was fair (AUROC = 0.74), but poor for unipolar, (AUROC = 0.68). The lowest tissue voltage values with capture were 0.03mV and 0.31mV respectively. In contrast, LIr had excellent discriminatory ability (AUROC – MiFi = 0.87, SP = 0.90, lowest value with tissue capture = 1Ω for both MiFi and SP). For the PA-EA cut-off, the ability to distinguish PT above/below 5mA for bipolar voltages was fair (AUROC = 0.69, optimal cut-off 1.29mV), and poor for unipolar voltages, (AUROC = 0.63). In contrast, LIr had good discrimination, (AUROC - MiFi = 0.82, optimal cut-off 12.5Ω, SP = 0.89, optimal cut-off 10.5Ω). Using these cut-offs, there was a significant difference between PTs between EI, PA and EA, for bipolar voltage, (EI: 20mV, PA 6.0 ± 6.3mV, EA: 2.6 ± 2.6mV, p &amp;lt; 0.0005) and LIr, (MiFi: EI: 20mV, PA 7.8 ± 7.5mV, EA: 2.8 ± 2.8mV. SP: EI 20mV, PA: 4.0 ± 2.5mV, EA: 2.2 ± 0.9mV, both p &amp;lt; 0.0005, [Figure 2]). Conclusions PTs suggest conventional voltage cut-offs could be improved. LIr shows potential as a novel parameter in assessing tissue health complimentary to bipolar voltages. Based on pacing capture data, what has previously been labelled dense scar is not electrically inert and should be ablated if clinically indicated. Values of 0.03mV and 1.31mV, and for potential future LIr mapping, 0.5Ω and 10.5Ω are suggested as dense scar and low voltage area thresholds.