While the intersection of blockchains and the Internet of Things (IoT) have received considerable research interest lately, Nakamoto-style blockchains possess a number of qualities that make them ...poorly suited for many IoT scenarios. Specifically, they require high network connectivity and are power-intensive. This is a drawback in IoT environments where battery-constrained nodes form an unreliable ad hoc network such as in digital agriculture. In this paper we present Vegvisir, a partition-tolerant blockchain for use in power-constrained IoT environments with limited network connectivity. It is a permissioned, directed acyclic graph (DAG)-structured blockchain that can be used to create a shared, tamperproof data repository that keeps track of data provenance. We discuss the use cases, architecture, and challenges of such a blockchain.
Treating potential polluted water sources is urgent and challenging, especially for natural water sources. Numerous research groups focus on either smart water monitoring or new adsorbent. However, ...either aspect alone is insufficient for complex nature water source treatment. Here, integrating the state‐of‐art machine learning technique, a sustainable silk‐based bioadsorbent, and wireless Internet of Things, an integrated automated drone‐delivery solar driven onsite water monitoring & treatment system (WMTS) for the contaminated nature water sources is developed. In short, the embedded sensors and microprogrammed control unit capture and upload the real‐time monitoring data to the cloud server for data analysis and optimized treatment strategy. Meanwhile, a grid map system based on the satellite remote sensing images directs the minimum number of WMTS units to cover the entire polluted region. Finally, unmanned aerial vehicles provide autonomous dispatch, operation, and maintenance, especially in hard‐to‐reach sites. Overall, this work offers a general, sustainable, energy‐efficient, and closed‐loop solution toward efficiently alerting and on‐site treating nature water source contamination.
An integrated automated air‐delivery solar driven onsite water monitoring & treatment system for efficient and sustainable treatment of natural water sources is developed. The system consists of the Internet of Things‐based real‐time and continuous water monitoring unit and the bioadsorbent silk fibroin film‐based sustainable water purification unit. The dispatch and maintenance of the system is carried out by unmanned aerial vehicles.
Papyrus (Cyperus papyrus) wetlands support millions through food provisioning, which leads to loss of regulating ecosystem services. This study aimed at understanding the impact of changes in water ...regime and vegetation harvesting on nutrient retention in rooted papyrus wetlands. A simulation model (Papyrus Simulator), developed and calibrated with data from African wetlands, produced reasonable estimates of productivity and nutrient retention. Phosphorus retention was lower than nitrogen retention, leading to a nitrogen-limited environment by reducing the N:P ratio in the water. Absence of surface water during part of the year caused a reduction of biomass. Harvesting increased nitrogen retention from 7% to over 40%, and phosphorus retention from 4% to 40%. Sensitivity analysis revealed assimilation, mortality, decay, re-translocation, nutrient inflow and soil porosity as the most influential factors. Papyrus Simulator is suitable for studying nutrient retention and harvesting in wetlands, and contributes to quantification of ecosystem services and sustainable wetland management.
•Papyrus Simulator is a dynamic simulation model to estimate nutrient retention in rooted Cyperus papyrus dominated wetlands.•The model was calibrated with data from selected field studies on Cyperus papyrus dominated wetlands.•Simulated biomass and water quality results were within the range of published data from over 40 papyrus wetlands in Africa.•The main mechanism for nitrogen and phosphorus retention was peat formation.
The west African Ebola epidemic that began in 2013 exposed deep inadequacies in the national and international institutions responsible for protecting the public from the far-reaching human, social, ...economic, and political consequences of infectious disease outbreaks. The Ebola epidemic raised a crucial question: what reforms are needed to mend the fragile global system for outbreak prevention and response, rebuild confidence, and prevent future disasters?
Papyrus (
Cyperus papyrus
) wetlands around East African lakes provide important ecosystem services, including retention of nutrients, to millions of people. To understand the processes contributing ...to nitrogen retention in the wetland and to evaluate the effects of papyrus harvesting, a dynamic model for carbon and nitrogen cycling in rooted papyrus wetlands was constructed. The model consisted of sub-models for the permanently (P) and seasonally (S) flooded zones and was based on data from a papyrus wetland in Naivasha, Kenya. In each zone, water, nitrogen and carbon flows were calculated based on descriptions of hydrological (river flow, lake level, precipitation, evaporation) and ecological (e.g. photosynthesis, nitrogen uptake, mineralisation, nitrification) processes. Literature data were used for parameterization and calibration. The model simulated realistic concentrations of dissolved nitrogen and papyrus biomass density of papyrus. Daily harvesting up to about 84 (S-zone) and 60 (P-zone) g/m
2
days dry weight reduced the aboveground biomass and increased nitrogen retention (expressed as
N
inflow
-
N
outflow
/
N
inflow
∗
100
%
) to 38 % (S-zone) and 50 % (P-zone). A further increase in daily harvesting resulted in collapse of the aboveground biomass. Papyrus biomass, however, recovered fully from annual harvesting of up to 100 % of the biomass. The model showed that papyrus re-growth after harvesting is nitrogen-limited in the P-zone.
Women make up only 28% of the workforce in STEM fields. It's important to engage more girls in learning STEM; however, girls' interests in STEM careers keep declining. It is well studied that the ...lack of sense of belonging underlies gender differences in STEM differentiation and achievement. Researchers have found that secondary girls' sense of belonging declines as they age. To enhance secondary female students' interests and self- concept in computing and engineering fields, the UNLV ITEST project sets the focus on engaging Girls in Ubiquitous Intelligence and Computing (GUIC) through a constructivist learning environment. In the GUIC Summer Camp, 40 secondary female students will take three-week training courses in Arduino & Internet of Things and Robotics Design and conduct two-week engineering project development in tiered teams co-mentored by STEM teachers and college student mentors. Based on the active learning method, the training courses are designed with interactive lectures and hands-on labs/activities. The engineering projects in ubiquitous intelligent systems are designed to connect computing & engineering concepts with real-world problems. Project demo results and students' feedbacks have confirmed the effectiveness of the project activities in enhancing female students' interests and self-efficacy in learning engineering and STEM. The unique constructivist learning environment is helpful in improving female students' sense of belonging in STEM.
•There is renewed interest in using capitation for primary care reimbursement.•Capitation can allow for greater flexibility in primary care teams and workflow.•Higher levels of capitation may improve ...some but not all aspects of preventive care.
There is increasing interest in using capitation rather than fee for service to promote primary care and population health. The goal of this study was to examine the association between practice reimbursement mix (majority fee for service versus majority capitation versus other) and receipt of common preventive screening examinations and health counseling from 2012 to 2018.
Using the National Ambulatory Medical Care Survey, a retrospective cross-sectional study of 24,864 visits with primary care clinicians among patients aged 18–75 years without a cancer diagnosis was conducted. The main dependent measures were age- and sex-appropriate receipt of breast cancer screening, osteoporosis screening, cervical cancer screening, chlamydia testing, colon cancer screening, diabetes screening, and hyperlipidemia screening as well as 3 health counseling items. Multivariable logistic regression was performed to assess the association between reimbursement mix and receipt of preventive care, adjusted for patient, visit, and practice characteristics.
Majority capitation reimbursement was associated with a greater likelihood of receiving breast cancer screening (AOR=2.11, 95% CI=1.16, 3.84, p=0.014) and osteoporosis screening (AOR=4.34, 95% CI=1.74, 10.8, p=0.0017) than majority fee-for-service or other reimbursement mixes. Reimbursement mix was not associated with the likelihood of receiving 9 other preventive care or health counseling services.
Larger amounts of capitation reimbursement may improve some but not all aspects of preventive care compared with fee for service.
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