scholarly journals New Approach to the Assessment of Insecticide Losses from Paddy Fields Based on Frequent Sampling Post Application

Agronomy ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1615
Author(s):  
Cheng Chen ◽  
Wan Luo ◽  
Jiarong Zou ◽  
Zhonghua Jia
Keyword(s):  
Paddy Fields ◽  
Time Interval ◽  
Dynamic Feature ◽  
High Concentration ◽  
Factors Affecting ◽  
Long Time ◽  
Pulse Type ◽  
Field Edge ◽  
Receiving Waters ◽  
Frequent Sampling

High concentration of insecticides may appear in waters surrounding paddy fields shortly after application. Capturing the dynamic feature of this insecticide pulse may help control insecticide load to receiving waters. Based on continuous monitoring of the drainage process and two monitoring campaigns of three insecticides—chlorpyrifos, abamectin and thiamethoxam—in a paddy, this study examined the pattern of insecticide concentrations at different locations of paddy waters during the period of insecticide application accompanied with pest-control irrigation, and analyzed the factors affecting the environmental behavior of these insecticides. The results showed that the pulse-type drainage exhibited the following features: short duration (normally less than 1 d), large flow rate (as large as 4 L s−1), frequent occurrence (20 times during a 40-d period) and long time interval (as long as 5 d). Concentrations of the insecticides with higher Henry’s constant and vapor pressure peaked quickly (within several hours) post application in the field ditch; more than half of chlorpyrifos and abamectin loads were detected within merely 1 h after application. The high insecticide concentrations in the ditch were partly attributed to the primary and secondary drift. Moreover, a new kinetic model was proposed to describe the behavior of chlorpyrifos at the field edge. It is recommended that controlled drainage be implemented for at least 1 d post application to prevent the loss of insecticides. Findings from this study may provide new insights into insecticide behavior in the paddy environment for preventing adverse environmental impacts.

scholarly journals Factors Affecting Water Drainage Long-Time Series in the Salinized Low-Lying Coastal Area of Ravenna (Italy)

Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 256
Author(s):  
Beatrice Maria Sole Giambastiani ◽  
Vito Raffaele Macciocca ◽  
Mario Molducci ◽  
Marco Antonellini
Keyword(s):  
Time Series ◽  
Coastal Area ◽  
Soil Depth ◽  
Precipitation Amount ◽  
Time Interval ◽  
Water Drainage ◽  
Factors Affecting ◽  
Long Time Series ◽  
Aquifer Salinization ◽  
Long Time

The low-lying coastal area of Ravenna (North-eastern Italy), like the majority of delta and coastal zones around the world, is affected by groundwater salinization due to natural processes (such as low topography, natural land subsidence, seawater encroachment along estuaries, etc.) and anthropogenic activities (i.e., increased anthropogenic subsidence rate, sea level rise, geofluids extraction, and drainage). Among all factors causing aquifer salinization, water drainage plays an important role in lowering the hydraulic head and favouring saltwater seepage in the Ravenna coastal aquifer. A network of drainage canals and water pumping stations first allowed for the reclamation of the low-lying territory and today are fundamental to keep land and infrastructures dry and maintain effective soil depth for agriculture practices. The aim of this work is to identify and assess factors affecting water drainage long-time series (1971–2017) of the most important mechanical drainage basin in this low-lying coastal area. Statistical analyses of drainage, climate, and land use change datasets help constrain the relative weight of each single factor potentially causing an increase of water drainage through time. The results show that, among these factors, subsidence rates and seepage processes are the most significant. The data trends also indicate that the climate, especially in terms of precipitation amount and extreme events, played no important role during the studied time interval. The process of infiltration soil capacity loss due to urbanization and consequent soil sealing probably has a small secondary effect. Moreover, an increase in pumping through time will exacerbate aquifer salinization and compromise freshwater availability in the coastal area.

An Adaptive and Learning System for Feedback-Controlled Evoked Response Studies

1981 ◽  
Vol 20 (03) ◽  
pp. 169-173
Author(s):  
J. Wagner ◽  
G. Pfurtscheixer
Keyword(s):  
Brain Activity ◽  
Evoked Response ◽  
Learning System ◽  
Time Interval ◽  
Electrical Brain Activity ◽  
Long Time ◽  
The Subject ◽  
Eeg Power ◽  
Stimulation System ◽  
Background Eeg

The shape, latency and amplitude of changes in electrical brain activity related to a stimulus (Evoked Potential) depend both on the stimulus parameters and on the background EEG at the time of stimulation. An adaptive, learnable stimulation system is introduced, whereby the subject is stimulated (e.g. with light), whenever the EEG power is subthreshold and minimal. Additionally, the system is conceived in such a way that a certain number of stimuli could be given within a particular time interval. Related to this time criterion, the threshold specific for each subject is calculated at the beginning of the experiment (preprocessing) and adapted to the EEG power during the processing mode because of long-time fluctuations and trends in the EEG. The process of adaptation is directed by a table which contains the necessary correction numbers for the threshold. Experiences of the stimulation system are reflected in an automatic correction of this table. Because the corrected and improved table is stored after each experiment and is used as the starting table for the next experiment, the system >learns<. The system introduced here can be used both for evoked response studies and for alpha-feedback experiments.

Using Self-report to Study How Application affect Motivation of Behavior Change (Preprint)

2020 ◽  
Author(s):  
Yuan Yin ◽  
Yurong Yu
Keyword(s):  
Behavior Change ◽  
Self Report ◽  
Group Method ◽  
Behavior Changes ◽  
Technology Design ◽  
Factors Affecting ◽  
Negative Results ◽  
Long Time ◽  
Ecological Momentary ◽  
Positive Effect

BACKGROUND Currently, changing behaviors with the assistance of mobile applications has been popularized. However, most of the participants are unable to persist in participating in behavior-changing activities for a long time. Some researchers have studied what factors motivate people to maintain behaviors-changing actions. There has been controversy about whether the commonly used triggers, negative results or competitions, could motivate behavior changes. In the meantime, the main methodology these researchers have been using is to conduct experiments, from which data was collected from subjects’ recalling previous behavior changing. The experiments are time-consuming, and the results can be unreliable. To resolve this problem, the Ecological Momentary Assessment (EMA) was developed to record real-time feedback. However, the EMA unavoidably increases the workload of the subjects. OBJECTIVE This study investigated the factors affecting behavior change, especially from the motivation aspect. Additionally, this paper attempted to identify a way to record human behavior changes without increasing the subjects’ workload. METHODS The methodology of “self-report” was adopted to report how people’s views regarding the behavior-changing intervention. To achieve a balance between workload and being timely, the self-reporting data was recorded once a day. After the 28-day “self-report” experiment, the “focus group” method was used to gather people’s feedback on behavior changing process. RESULTS This paper identified 9 factors: cooperation, competition, award, understandable graphic, reminder and alarm, trust and willing, gender, relation with disease and environmental factors). These factors could affect motivation of behavior changing. Besides, we found that negative results could be a motivation for behavior changing. In the experiment, we also found that a small number of subjects tended to cheat for a more “beautiful” result. The last part of the paper has presented possible implications for technology design to facilitate behavior-changing. CONCLUSIONS In particular, (i) the research promoted the possibility of cheating when recording data which is ignored by existing research and will make the digital applications less useful; (ii) the results show that not all cooperation is needed to lead to a positive effect; (iii) the research identified the negative results caused by over-competition in behavior change. Finally, the paper proposes technology design directions should focus on giving motivation through keeping dairy, negative results feedback and avoid cheating.

scholarly journals Population estimates of Antillean manatees in Puerto Rico: an analytical framework for aerial surveys using multi-pass removal sampling

2019 ◽  
Vol 100 (4) ◽  
pp. 1340-1349
Author(s):  
Jaime A Collazo ◽  
Matthew J Krachey ◽  
Kenneth H Pollock ◽  
Francisco J Pérez-Aguilo ◽  
Jan P Zegarra ◽  
...  
Keyword(s):  
Puerto Rico ◽  
Detection Probability ◽  
Analytical Framework ◽  
Population Estimates ◽  
High Concentration ◽  
Imperfect Detection ◽  
Factors Affecting ◽  
Management Actions ◽  
Aerial Surveys ◽  
Population Size Estimates

AbstractEffective management of the threatened Antillean manatee (Trichechus manatus manatus) in Puerto Rico requires reliable estimates of population size. Estimates are needed to assess population responses to management actions, and whether recovery objectives have been met. Aerial surveys have been conducted since 1976, but none adjusted for imperfect detection. We summarize surveys since 1976, report on current distribution, and provide population estimates after accounting for apparent detection probability for surveys between June 2010 and March 2014. Estimates in areas of high concentration (hotspots) averaged 317 ± 101, three times higher than unadjusted counts (104 ± 0.56). Adjusted estimates in three areas outside hotspots also differed markedly from counts (75 ± 9.89 versus 19.5 ± 3.5). Average minimum island-wide estimate was 386 ± 89, similar to the maximum estimate of 360 suggested in 2005, but fewer than the 700 recently suggested by the Puerto Rico Manatee Conservation Center. Manatees were more widespread than previously understood. Improving estimates, locally or island-wide, will require stratifying the island differently and greater knowledge about factors affecting detection probability. Sharing our protocol with partners in nearby islands (e.g., Cuba, Jamaica, Hispaniola), whose populations share genetic make-up, would contribute to enhanced regional conservation through better population estimates and tracking range expansion.El manejo efectivo del manatí antillano amenazado en Puerto Rico requiere estimados de tamaños de poblaciónes confiables. Dichas estimaciones poblacionales son necesarias para evaluar las respuestas a las acciones de manejo, y para determinar si los objetivos de recuperación han sido alcanzados. Se han realizado censos aéreos desde 1976, pero ninguno de ellos han sido ajustados para detecciones imperfectas. Aquí resumimos los censos desde 1976, actualizamos la distribución, y reportamos los primeros estimados poblacionales ajustados para la probabilidad de detección aparente en los censos de Junio 2010 a Marzo 2014. Las estimaciones poblacionales en áreas de mayor concentración del manatí promedió 317 ± 103, tres veces más abundante que los conteos sin ajuste (104 ± 0.56). Las estimaciones poblacionales en tres áreas fuera de las áreas de mayor concentración del manatí también fueron marcadamente diferentes (75 ± 9.89 vs 19.5 ± 3.5). El estimado mínimo poblacional en la isla entera fue de 386 ± 89, similar al estimado máximo de 360 sugerido en el año 2005, pero menor a los 700 sugeridos recientemente por el Centro de Conservación de Manatíes de Puerto Rico. Documentamos que el manatí tiene una distribución más amplia de lo que se sabía con anterioridad. El mejoramiento de los estimados poblacionales locales o a nivel de isla requerirá que se estratifique a la isla en forma diferente y que se investiguen los factores que influencian a la probabilidad de detección. Compartir protocolos como este con colaboradores de islas vecinas (por. ej., Cuba, Jamaica, Española), cuyas poblaciones de manatíes comparten material genético, contribuiría a la conservación regional mediante mejores estimaciones poblacionales y monitoreo de la expansión de su ámbito doméstico.

scholarly journals Core Elements Affecting Sharing: Evidence from the United States

2021 ◽  
Vol 13 (7) ◽  
pp. 3943
Author(s):  
Aurelija Burinskienė ◽  
Edita Leonavičienė ◽  
Virginija Grybaitė ◽  
Olga Lingaitienė ◽  
Juozas Merkevičius
Keyword(s):  
United States ◽  
The United States ◽  
Collaborative Consumption ◽  
Factors Affecting ◽  
Use Of Resources ◽  
Personal Consumption ◽  
Depth Analysis ◽  
Core Elements ◽  
Long Time ◽  
Number Of Visits

The new phenomenon called sharing or collaborative consumption emerged a decade ago and is continuously growing. It creates new possibilities for society, and especially for business, is beneficial for the environment, makes more efficient use of resources, and presents a new competitive business model. The scientific literature lacks a more in-depth analysis of the factors influencing sharing activity growth; therefore, the paper’s authors attempt to fill this gap. The authors aim to identify the factors affecting the use of sharing platforms. To reach the goal, the authors developed a regression model and constructed a list of 71 variables. The study used monthly United States data from January 2017 to June 2020 from the publicly available Federal Reserve Economic Data (FRED)and Google trends databases. The comparison to other indexes proves that the proposed index, representing the number of visits to sharing platforms (SEP), is a unique one. The first index allowed us to revise the sharing activity monthly. The authors identified that variables such as wage level, social network users, import level, and personal consumption are critical in affecting the number of visits to sharing platforms. The presented framework could be helpful for practitioners and policymakers analysing the stimulation of sharing or collaborative consumption. It includes indicators representing different areas, such as society, technology, and country, and allows for monthly investigations. Such activity was evident for a long time when online platforms contributed to its wider accessibility. The results help to forecast the number of visits monthly. Sharing is still an emerging area for research; thus, the authors tried to explore the phenomenon of sharing to expand the conceptual level of knowledge.

scholarly journals Financing Growth through Remittances and Foreign Direct Investment: Evidences from Balkan Countries

2021 ◽  
Vol 14 (3) ◽  
pp. 117
Author(s):  
Esmeralda Jushi ◽  
Eglantina Hysa ◽  
Arjona Cela ◽  
Mirela Panait ◽  
Marian Catalin Voica
Keyword(s):  
Developing Economies ◽  
Central Banks ◽  
Sustainable Growth ◽  
Time Interval ◽  
Foreign Direct Investments ◽  
Factors Affecting ◽  
Balkan Countries ◽  
To Come ◽  
Sustainable Economic Growth ◽  
The Impact

The ultimate goal of central banks, worldwide, is to promote the foundations for sustainable economic growth. In the case of developing economies, in particular, such objective requires time, huge efforts, attention, and plenty of resources in order to be accomplished to the fullest degree. This paper thoroughly investigates key factors affecting Balkan countries’ economic development (as measured by gross domestic product (GDP) growth), focusing especially on the impact of remittances. The analysis was done over an 18-year time interval (2000–2017) and builds on 144 observations. The data figures were retrieved from the World Bank database while two dummies were created to test the impact of the last financial crisis (2008–2012). Econometric tools were employed to carry out a broad analysis on the interdependencies that exist and, in particular, to determine the role of remittance income on growth. The vector auto regressive model was estimated using EViews software, and was used to come up with relevant insights. Empirical findings suggest the following: population growth, remittances, and labor force participation are insignificant factors for sustainable growth. On the other hand, previous levels of GDP, trade, and foreign direct investments (FDIs) appear to be relevant for the predictor. This research provides up-to-date conclusions, which can be considered during the decision-making process of central banks, as well as by government policymakers.

scholarly journals Optimal Perturbations of an Oceanic Vortex Lens

Fluids ◽  
2018 ◽  
Vol 3 (3) ◽  
pp. 63 ◽  
Author(s):  
Thomas Meunier ◽  
Claire Ménesguen ◽  
Xavier Carton ◽  
Sylvie Le Gentil ◽  
Richard Schopp
Keyword(s):  
Normal Mode ◽  
Growth Rates ◽  
Time Interval ◽  
Time Intervals ◽  
Horizontal Structure ◽  
Azimuthal Wave ◽  
Wave Numbers ◽  
Non Linear ◽  
Long Time ◽  
Short Time

The stability properties of a vortex lens are studied in the quasi geostrophic (QG) framework using the generalized stability theory. Optimal perturbations are obtained using a tangent linear QG model and its adjoint. Their fine-scale spatial structures are studied in details. Growth rates of optimal perturbations are shown to be extremely sensitive to the time interval of optimization: The most unstable perturbations are found for time intervals of about 3 days, while the growth rates continuously decrease towards the most unstable normal mode, which is reached after about 170 days. The horizontal structure of the optimal perturbations consists of an intense counter-shear spiralling. It is also extremely sensitive to time interval: for short time intervals, the optimal perturbations are made of a broad spectrum of high azimuthal wave numbers. As the time interval increases, only low azimuthal wave numbers are found. The vertical structures of optimal perturbations exhibit strong layering associated with high vertical wave numbers whatever the time interval. However, the latter parameter plays an important role in the width of the vertical spectrum of the perturbation: short time interval perturbations have a narrow vertical spectrum while long time interval perturbations show a broad range of vertical scales. Optimal perturbations were set as initial perturbations of the vortex lens in a fully non linear QG model. It appears that for short time intervals, the perturbations decay after an initial transient growth, while for longer time intervals, the optimal perturbation keeps on growing, quickly leading to a non-linear regime or exciting lower azimuthal modes, consistent with normal mode instability. Very long time intervals simply behave like the most unstable normal mode. The possible impact of optimal perturbations on layering is also discussed.

scholarly journals Computer-Assisted System in Stress Radiography for Anterior Cruciate Ligament Injury with Correspondent Evaluation of Relevant Diagnostic Factors

Diagnostics ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 419
Author(s):  
Chien-Kuo Wang ◽  
Liang-Ching Lin ◽  
Yung-Nien Sun ◽  
Cheng-Shih Lai ◽  
Chia-Hui Chen ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Cruciate Ligament ◽  
Anterior Tibial Translation ◽  
Computer Assisted ◽  
Time Interval ◽  
Stress Radiography ◽  
Factors Affecting ◽  
Anterior Tibial ◽  
Anterior Cruciate ◽  
Tibial Translation

We sought to design a computer-assisted system measuring the anterior tibial translation in stress radiography, evaluate its diagnostic performance for an anterior cruciate ligament (ACL) tear, and assess factors affecting the diagnostic accuracy. Retrospective research for patients with both knee stress radiography and magnetic resonance imaging (MRI) at our institution was performed. A complete ACL rupture was confirmed on an MRI. The anterior tibial translations with four different methods were measured in 249 patients by the designed algorithm. The diagnostic accuracy of each method in patients with all successful measurements was evaluated. Univariate logistic regression analysis for factors affecting diagnostic accuracy of method four was performed. In the inclusive 249 patients, 177 patients (129 with completely torn ACLs) were available for analysis. Mean anterior tibial translations were significantly increased in the patients with a completely torn ACL by all four methods, with diagnostic accuracies ranging from 66.7% to 75.1%. The diagnostic accuracy of method four was negatively associated with the time interval between stress radiography and MRI as well as force-joint distance on stress view, and not significantly associated with age, gender, flexion angle, intercondylar distance, and force-joint angle. A computer-assisted system measuring the anterior tibial translation in stress radiography showed acceptable diagnostic performance of complete ACL injury. A shorter time interval between stress radiography and MRI as well as shorter force-joint distance were associated with higher diagnostic accuracy.

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