A Combination of Spatial Domain Filters to Detect Surface Ocean Current from Multi-Sensor Remote Sensing Data

This research investigates the applicability of combining spatial filter’s algorithm to extract surface ocean current. Accordingly, the raster filters were tested on 80–13,505 daily images to detect Kuroshio Current (KC) on weekly, seasonal, and climatological scales. The selected raster filters are convolution, Laplacian, north gradient, sharpening, min/max, histogram equalization, standard deviation, and natural break. In addition, conventional data set of sea surface currents, sea surface temperature (SST), sea surface height (SSH), and non-conventional data such as total heat flux, surface density (SSD), and salinity (SSS) were employed. Moreover, controversial data on ocean color are included because very few studies revealed that chlorophyll-α is a proxy to SST in the summer to extract KC. Interestingly, the performance of filters is uniform and thriving for seasonal and on a climatological scale only by combining the algorithms. In contrast, the typical scenario of identifying Kuroshio signatures using an individual filter and by designating a value spectrum is inapplicable for specific seasons and data set. Furthermore, the KC’s centerlines computed from SST, SSH, total heat flux, SSS, SSD, and chlorophyll-α correlate with sea surface currents. Deviations are observed in the various segments of Kuroshio’s centerline extracted from heat flux, chlorophyll-α, and SSS flowing across Tokara Strait from northeast Taiwan to the south of Japan.

Assessing Spatial Vulnerability of Bangladesh to Climate Change and Extremes: A Geographic Information System Approach

Regarding climate change, the world’s most discussed issue for the last few decades, countries like Bangladesh are always noteworthy due to its susceptibility resulting from its geography, hazard proneness, and socioeconomic condition. Thus, this aimed to justify the hypothesis that Bangladesh has spatial diversity in sectors of Climate Change Vulnerability (CCV) by identifying the sectors of vulnerability and visualizing the spatial distribution of vulnerability through multivariate geospatial analysis in the GIS environment. For an integrated assessment of CCV, 38 indicators (socio-economic and biophysical) have been incorporated in the IPCC framework in raster form. Test statistics have shown Kiser-Meyer-Olkin (KMO) value is 0.73 and the p-value of Bartlett’s sphericity is 0. The principal component analysis resulted in 6 principal components with 73.52% total explained variance. Sectors of CCV are the Climatic extreme event vulnerability (PC1), Meteorological shift vulnerability (PC2), Infrastructure and demographic vulnerability (PC3), Ecological vulnerability (PC4), Flood vulnerability (PC5), and Economic vulnerability (PC6) with Cronbach’s alpha 0.90, 0.81, 0.88, 0.72, 0.72, and 0.66 respectively. Among 3 clusters (Jenk’s Natural break) of weighted averaged indices, the highly vulnerable cluster has shown that the PC1 has the highest magnitude with a score of 0.53–0.87, while the PC5 has the highest spatial coverage with 24 districts. The present study however is a new edition in climate vulnerability assessment in Bangladesh since it encompasses multivariate spatial analysis to demonstrate countrywide CCV. This study should be an important tool for setting adaptation and mitigation strategies from the root level to policymaking platforms of Bangladesh.

Statistical Analysis for Tidal Flat Classification and Topography Using Multitemporal SAR Backscattering Coefficients

Coastal zones are very dynamic natural systems that experience short-term and long-term morphological changes. Their highly dynamic behavior requires frequent monitoring. Tidal flat topography for a large spatial coverage has been generated mainly by the waterline extraction method from multitemporal remote sensing observations. Despite the efficiency and robustness of the waterline extraction method, the waterline-based digital elevation model (DEM) is limited to representing small scale topographic features, such as localized tidal tributaries. Tidal flats show a rapid increase in SAR backscattering coefficients when the tide height is lower than the tidal flat topography compared to when the tidal flat is covered by water. This leads to a tidal flat with a distinct statistical behavior on the temporal variability of our multitemporal SAR backscattering coefficients. Therefore, this study aims to suggest a new method that can overcome the constraints of the waterline-based method by using a pixel-based DEM generation algorithm. Jenks Natural Break (JNB) optimization was applied to distinguish the tidal flat from land and ocean using multitemporal Senitnel-1 SAR data for the years 2014–2020. We also implemented a logistic model to characterize the temporal evolution of the SAR backscattering coefficients along with the tide heights and estimated intertidal topography. The Sentinel-1 DEM from the JNB classification and logistic function was evaluated by an airborne Lidar DEM. Our pixel-based DEM outperformed the waterline-based Landsat DEM. This study demonstrates that our statistical approach to intertidal classification and topography serves to monitor the near real-time spatiotemporal distribution changes of tidal flats through continuous and stable SAR data collection on local and regional scales.

Strategizing COVID-19 lockdowns using mobility patterns

During the COVID-19 pandemic, governments have attempted to control infections within their territories by implementing border controls and lockdowns. While large-scale quarantine has been the most successful short-term policy, the enormous costs exerted by lockdowns over long periods are unsustainable. As such, developing more flexible policies that limit transmission without requiring large-scale quarantine is an urgent priority. Here, the dynamics of dismantled community mobility structures within US society during the COVID-19 outbreak are analysed by applying the Louvain method with modularity optimization to weekly datasets of mobile device locations. Our networks are built based on individuals' movements from February to May 2020. In a multi-scale community detection process using the locations of confirmed cases, natural break points from mobility patterns as well as high risk areas for contagion are identified at three scales. Deviations from administrative boundaries were observed in detected communities, indicating that policies informed by assumptions of disease containment within administrative boundaries do not account for high risk patterns of movement across and through these boundaries. We have designed a multi-level quarantine process that takes these deviations into account based on the heterogeneity in mobility patterns. For communities with high numbers of confirmed cases, contact tracing and associated quarantine policies informed by underlying dismantled community mobility structures is of increasing importance.

Spatial Heterogeneity and Socio-economic Correlates of Unmet Need for Spacing in India: Evidences From National Family Health Survey, 2015-16

Background:The high unmet need for contraception among women who wants to delay their subsequent births for two or more years is a challenging issue in India. Therefore, the present study aims to display spatial heterogeneity and determine the associated factors underlying the unmet need for contraception among the currently married women aged 15-49 years with a demand for spacing births in India.Methods:The present study used data from the National Family and Health Survey, 2015-16. Unmet need for spacing (UNS) used as outcomes and socio-cultural and demographic factors as explanatory variables. Among the comprehensive family planning, 16.7% (56742 women) of currently married women had demand for spacing births were used for analysis. Univariate, bivariate with chi-square significance test, spatial natural break technique, and multivariate logistic regression were used to accomplish the study objectives. Results:Almost 17% of women had demand spacing out of total demand for family planning in India. High unmet need for contraception found among them except the women with higher-level education and wealth status. District level spatial heterogeneity of UNS shows 119 districts had very high unmet for spacing (69% and above). Results from multivariate logistic regression show that UNS's likelihood was noticeably high among the women with parity three or more (AOR: 1.42 [1.3-1.55]) compared to their counterparts. Similarly, 44% (AOR: 1.44[1.38-1.51]) more likely found among the OBC than General caste. Rural (AOR: 1.24[1.19-1.30]) women compared to urban, women living in South (AOR: 6.19 [5.76-6.65]), Central (AOR: 1.52 [1.43-1.61]), and West (AOR: 1.80 [1.68-1.92]) region compared to those from North had higher odds of UNS. Conclusion:Deal with the UNS in India requires scaling up women education, client choice-based services, campaign on benefits of spacing births and available contraception, and socio-economically backward group centric policies.

Spatial Heterogeneity and Socio-economic Correlates of Unmet Need for Spacing Contraception in India: Evidences from National Family Health Survey, 2015-16

Background:The high unmet need for contraception among women who wants to delay their subsequent births for two or more years (UNS) is a challenging issue in India. Therefore, the present study aims to display spatial heterogeneity and determine the associated factors underlying the UNS among the currently married women aged 15-49 years with a demand for spacing births in India.Methods:The present study used data from the National Family and Health Survey, 2015-16. Unmet need for spacing (UNS) used as outcomes and socio-cultural and demographic factors as explanatory variables. Among the comprehensive family planning, 16.7% (56742 women) of currently married women had demand for spacing births were used for analysis. Univariate, bivariate with chi-square significance test, spatial natural break technique, and multivariate logistic regression were used to accomplish the study objectives. Results:Almost 17% of women had demand spacing out of total demand for family planning in India. High unmet need for contraception found among them except the women with higher-level education and wealth status. District level spatial heterogeneity of UNS shows 248 districts had remarkably high unmet for spacing (68% and above). Results from multivariate logistic regression show that UNS's likelihood was noticeably high among the women with parity three or more (AOR: 1.42 [1.3-1.55]) compared to their counterparts. Similarly, 44% (AOR: 1.44[1.38-1.51]) more likely found among the OBC than General caste. Rural (AOR: 1.24[1.19-1.30]) women compared to urban, women living in South (AOR: 6.19 [5.76-6.65]), Central (AOR: 1.52 [1.43-1.61]), and West (AOR: 1.80 [1.68-1.92]) region compared to those from North had higher odds of UNS. Conclusion:Deal with the UNS in India requires scaling up women education, client choice-based services, campaign on benefits of spacing births and available contraception, and socio-economically backward group centric policies.

881 Delivering Consultant-Led Teaching During A Global Pandemic

Aim Providing high quality teaching has become increasingly difficult as social distancing and disrupted schedules caused by the COVID-19 pandemic make large in-person gatherings impractical. Yet the need and demand for this has only increased. We sought to use an innovative virtual + in-person format to facilitate delivery. Method We designed a 6-session ENT teaching programme for GP trainees over 3 evenings. Each session was consultant-led, delivered in-person in a large lecture theatre, and simultaneously broadcast on Microsoft Teams. The in-person element was intended to permit practical demonstrations, e.g., of the Dix-Hallpike test, to supplement presenter’s videos. Attendees could attend in-person or virtually. Sessions were timed to allow staff from the nearby hospital to join immediately after work. Results All attendees attended virtually. And all felt that the video demonstrations were sufficient, and that in-person replication was unnecessary. Course delivery was rated ‘very good’ or ‘excellent’ by 88% (n = 17), and the course overall was rated similarly by 94%. Several comments suggested that in future we focus on virtual delivery by shifting the starting time later to “allow a natural break after work”. Conclusions The COVID-19 pandemic has altered many aspects of our lives, and teaching delivery is not immune to this. The overwhelming preference for virtual attendance amongst our cohort suggests that many doctors are comfortable with, and even enthusiastic for, this change, and that teaching can still be effective. Future iterations of this course will likely emphasise the virtual element and record the sessions to allow for time-shifted viewing.

GIS-based Land Suitability Analysis for Surface Irrigation Using Analytical Hierarchy Process Method in East and West Bellessa, Northwestern Ethiopia

Bellessa is found in central Gondar, which is affected frequently by drought thanks to spatial and temporal failure of rainfall. Therefore, the agriculture in this area has to be supported by surface irrigation. For this, land suitability analysis for surface irrigation is extremely important to scale back food security problem. GIS-based land suitability analysis was conducted using analytical hierarchy process methods. Eight factors like slope, elevation, distance to water source, land use, soil texture, type, depth, and drainage are considered and therefore the weight of every parameter was estimated using 8x8 pairwise comparison matrix. After all, final land suitability map was generated using weighted overlay method under GIS tool. the ultimate map was classified into four land suitable classes using natural break classification method as highly suitable (S1), moderately suitable (S2), marginally suitable (S3), and not suitable class (S4). The result showed that highly suitable, moderately suitable, marginally suitable and not suitable class are covered 13.9%, 46.9%, 26.9%, and 12.2% of the whole area, respectively. This study finding will features a vital role in conducting surface irrigation considering the input parameters and therefore the final demarcated suitable land classes.

Measuring threshold and latency of motion perception on a swinging bed

Introduction Our objective was to develop and to evaluate a system to measure latency and threshold of pendular motion perception based on a swinging bed. Materials and methods This prospective study included 30 healthy adults (age: 32 ± 12 years). All subjects were tested twice with a 10 min. interval. A second trial was conducted 2 to 15 days after. A rehabilitation swinging bed was connected to an electronic device emitting a beep at the beginning of each oscillation phase with an adjustable time lag. Subjects were blindfolded and auditory cues other than the beep were minimized. The acceleration threshold was measured by letting the bed oscillate freely until a natural break and asking the patient when he did not perceive any motion. The perception latency was determined by asking the patient to indicate whether the beep and the peak of each oscillation were synchronous. The time lag between sound and peak of the head position was swept from -750 to +750 ms by 50 ms increments. Results The mean acceleration threshold was 9.2±4.60 cm/s2. The range width of the synchronous perception interval was estimated as 535±190 ms. The point of subjective synchronicity defined as the center of this interval was -195±106 ms (n = 30). The test-retest evaluation in the same trial showed an acceptable reproducibility for the acceleration threshold and good to excellent for all parameters related to sound-movement latency. Conclusion Swinging bed combined to sound stimulation can provide reproducible information on movement perception in a simple and non-invasive manner with highly reproducible results.

Stability of gold standard and its selected consequences: a comment

Kvasnicˇka (2007) attempts to demonstrate that the gold standard may be an unlikely alternative for small economies to revert to. The crux of his argument deals with supply considerations that could prove fatal to a fledgling currency. An influx of gold from the world’s existing gold stock, or its new production could prove to be a destabilising supply-side factor undermining the usability, and hence, adoption, of such a monetary system. We find fault with this for two main theoretical reasons. First, a distinction must be made between gold stock, and monetary gold. Second, the mechanism that creates monetary gold works as a natural break on unrestrained supply growth. Several additional clarifications are necessary as well, among them the role money supply plays in the trade cycle, and the casual relationship that exists between supply and price. Finally, an insightful comparison used linking monetary gold in a small economy to the use of cigarettes in a Second World War P.O.W. camp must be slightly altered to make a true comparison. Kvasnicˇka does a great service to free-marketers by providing a theoretical attack on the choice of gold as a medium of exchange, however, in light of this paper’s theoretical conclusions, the free-market defence of commodity money endures. JEL Classification: B53 – Austrian Economics, E42 – Monetary Systems, E51 – Money Supply.