scholarly journals Weed leucaena and its significance, implications and control

2019 ◽  
Vol 7 (4) ◽  
pp. 280-289 ◽  
Author(s):  
Shane Campbell ◽  
Wayne Vogler ◽  
Dannielle Brazier ◽  
Joseph Vitelli ◽  
Simon Brooks
Keyword(s):  
Control Strategies ◽  
Seed Banks ◽  
Effective Control ◽  
Tropical Regions ◽  
Code Of Practice ◽  
Keynote Paper ◽  
Disturbed Areas ◽  
Riparian Systems ◽  
Environmental Weed ◽  
And Control

Keynote paper presented at the International Leucaena Conference, 1‒3 November 2018, Brisbane, Queensland, Australia.Leucaena (Leucaena leucocephala) is widely recognized in many countries as a commercially valuable plant, particularly when used as a nutritious fodder in subtropical and tropical regions. However, it is also considered an environmental weed in some countries due to its ability to form dense infestations in disturbed areas, where it is not proactively managed or grazed. These different perspectives have made leucaena a contentious species. Ideally, landholders and relevant jurisdictions in charge of invasive species need to work together to minimize its spread as a weed and manage existing infestations. To date, the response has been varied, ranging from no action through to some jurisdictions formally recognizing leucaena as an environmental weed within relevant legislation and applying requirements to minimize its impact. Between these extremes, there are initiatives such as an industry Code of Practice (i.e. The Leucaena Network in Australia), recommending that those growing leucaena adhere to certain principles and practices to minimize the risk of spread from their operations. The biology of weed leucaena (e.g. large seed production, relatively long-lived seed banks) and the situations in which it spreads (e.g. roadsides and riparian systems) pose management challenges to landholders and relevant jurisdictions. Adaptive management and experimental research are necessary to identify effective control strategies for a range of situations.

Trajectory control of a mobile manipulator in the presence of base disturbance

SIMULATION ◽  
2018 ◽  
Vol 95 (6) ◽  
pp. 529-543 ◽  
Author(s):  
RV Ram ◽  
PM Pathak ◽  
SJ Junco
Keyword(s):  
Mobile Robot ◽  
Dynamic Models ◽  
Control Strategies ◽  
Effective Control ◽  
Mobile Manipulator ◽  
Dynamic Interactions ◽  
Additional Task ◽  
Manipulator Arm ◽  
And Control ◽  
Base Disturbance

A mobile manipulator is typically an assembly of a mobile robot base and an on-board manipulator arm. As the manipulator arm is mounted over the mobile robot base, the controller has the additional task of taking care of the disturbances of the mobile robot due to the dynamic interactions between the mobile robot base and manipulator arm. In the present work, dynamic models for the manipulator arm and an omni-wheeled mobile robot base were developed separately and then both were combined. Two control strategies, namely only manipulator arm control (OMAC) and simultaneous manipulator and base control (SMBC) were developed for the effective control of tip trajectory. In both strategies, an amnesia recovery coupled with classical proportional integral and derivative (PID) control was used. The bond graph methodology was used for the development of the dynamic model and control for the mobile manipulator. Simulation results are presented to illustrate the efficacy of the two control strategies.

Biology and control of Reseda lutea L. 1. Seed biology and seedling growth

1997 ◽  
Vol 48 (4) ◽  
pp. 511 ◽  
Author(s):  
J. W. Heap
Keyword(s):  
Seedling Growth ◽  
Control Strategies ◽  
Germination Rate ◽  
South Australia ◽  
Effective Control ◽  
Temperate Climate ◽  
Perennial Weed ◽  
Seed Biology ◽  
Early Seedling ◽  
And Control

Reseda lutea L. is a major perennial weed of alkaline cropping soils in South Australia. Seed biology and early seedling growth of R. lutea were studied in field and laboratory experiments to gain information needed for effective control strategies. Recovery of intact seeds buried for 4 years in the field at 50 and 150 mm was 77–96%. Germination of this seed was 33–63% (50 mm) and 0% (150 mm). Germination patterns differed markedly between seed collected from 2 populations. Seed germinated at all constant and fluctuating temperatures between 10 and 35° C with the maximum (88%) at 25°C constant. Mean temperature, rather than constancy or fluctuation, determined the germination rate. Light strongly inhibited germination. Seedling shoot growth was slow but tap root growth was rapid, reaching 350 mm within 28 days of emergence. Secondary roots arose 3–7 days after emergence and shoot buds formed on the roots within 28 days. R. lutea was found to be well adapted for persistence in cultivated fields with a temperate climate.

scholarly journals Effects of medical resource capacities and intensities of public mitigation measures on outcomes of COVID-19 outbreaks

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Xia Wang ◽  
Qian Li ◽  
Xiaodan Sun ◽  
Sha He ◽  
Fan Xia ◽  
...  
Keyword(s):  
Prevention And Control ◽  
Control Strategies ◽  
Control Measures ◽  
Mitigation Measures ◽  
Effective Control ◽  
Medical Resource ◽  
Key Factors ◽  
Medical Resources ◽  
Detection Rates ◽  
And Control

Abstract Background The COVID-19 pandemic is complex and is developing in different ways according to the country involved. Methods To identify the key parameters or processes that have the greatest effects on the pandemic and reveal the different progressions of epidemics in different countries, we quantified enhanced control measures and the dynamics of the production and provision of medical resources. We then nested these within a COVID-19 epidemic transmission model, which is parameterized by multi-source data. We obtained rate functions related to the intensity of mitigation measures, the effective reproduction numbers and the timings and durations of runs on medical resources, given differing control measures implemented in various countries. Results Increased detection rates may induce runs on medical resources and prolong their durations, depending on resource availability. Nevertheless, improving the detection rate can effectively and rapidly reduce the mortality rate, even after runs on medical resources. Combinations of multiple prevention and control strategies and timely improvement of abilities to supplement medical resources are key to effective control of the COVID-19 epidemic. A 50% reduction in comprehensive control measures would have led to the cumulative numbers of confirmed cases and deaths exceeding 590,000 and 60,000, respectively, by 27 March 2020 in mainland China. Conclusions Multiple data sources and cross validation of a COVID-19 epidemic model, coupled with a medical resource logistic model, revealed the key factors that affect epidemic progressions and their outbreak patterns in different countries. These key factors are the type of emergency medical response to avoid runs on medical resources, especially improved detection rates, the ability to promote public health measures, and the synergistic effects of combinations of multiple prevention and control strategies. The proposed model can assist health authorities to predict when they will be most in need of hospital beds and equipment such as ventilators, personal protection equipment, drugs, and staff.

scholarly journals DAIRY INDUSTRIAL HYGIENE: A REVIEW ON BIOFILM CHALLENGES AND CONTROL

2018 ◽  
Vol 6 (2) ◽  
pp. 268-273
Author(s):  
Ismail T. Kabwanga ◽  
Atila Yetişemiyen ◽  
Shakira Nankya
Keyword(s):  
Control Strategies ◽  
Dairy Industry ◽  
Raw Milk ◽  
Critical Issue ◽  
Modern Medicine ◽  
Production Equipment ◽  
Effective Control ◽  
Chemical Methods ◽  
Biofilm Growth ◽  
And Control

The development of biofilms and the microbial biofilm adherence into the production equipment and facilities used in the dairy industry is a critical issue that needs to be addressed. Biofilms lead to the contamination of food by pathogenic and spoilage m/os. The microbes cause both company loses due to unsafe spoilt products, equipment depreciation and death of consumers under severe pathogenic out breaks. Biofilms may also lead to a failure of anti- microbial therapy hence major threats to modern medicine. Biofilm formation however is a dynamic process with different mechanisms involved in the biofilm growth. Raw milk provides an ideal medium for the formation of a biofilm as it contains bacteria and is nutrient-rich. This paper gives highlights regarding microbial sources, challenges, biofilm control strategies that include but not limited to physical, mechanical, enzymatic and chemical methods for the effective control of formation and or eradicate biofilm in the dairy industry.

scholarly journals Study on spatial-temporal distribution and environmental ties of Japanese B Encephalitis’s mosquito vector as well as landing rate in The Olympic forest park

2020 ◽  
Author(s):  
Mei-De Liu ◽  
Yong Zhang ◽  
Ying Tong ◽  
Hong-Jiang Zhang ◽  
Qiu-Hong Li ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Control Strategies ◽  
Temporal Distribution ◽  
Effective Control ◽  
Mosquito Vector ◽  
Forest Park ◽  
The Public ◽  
Environmental Features ◽  
The People ◽  
And Control

Abstract Background: Mosquito surveillance is crucial for understanding the epidemic potential, planning early-warning, and effective control strategies. As a key public place in Beijing, the Beijing Olympic Forest Park (BOFP) makes serious epidemiological means for the Beijing, and the survey on the Japanese B Encephalitis (JBE) vector of Culex tritaeniorhynchus and mosquito landing in BOFP is crucial for the people living as well as JBE surveillance and control. It was hypothesized that the Cx. tritaeniorhynchus could be trapped in a well-urbanization area of Beijing, and the distribution of Cx. tritaeniorhynchus and mosquito landing rate are determined by the environmental factors. Methods: Thus, this investigation was performed to understand the spatial-temporal distribution of Cx. Tritaeniorhynchus and landing rate in BOFP, and the relationship between environmental features and densities of Cx. tritaeniorhynchus as well as mosquito landing rate, considering the vector competent of Cx. tritaeniorhynchus and important epidemiological means of BOFP in Beijing. From July to September, the Cx. tritaeniorhynchus was trapped with CDC-lights together with CO2 and the landing rate on the same sites as light traps were also investigated. What’s more, the ties of environmental factors to the density of Cx. tritaeniorhynchus and landing rate was performed with SPSS, after the environmental factors datasets had been extracted with the 3S procedures. Results: As result showed, the highest density of Cx. tritaeniorhynchus could be detected in September in the wetland environment, and the density was related to the grass-water in 400meters buffer (GW_400) and lower-trees in 100meter buffer distance (LT_100). For the landing rate investigation, the highest landing rates was observed in the wetland environment during September. In addition, there were two environmental features could be identified to correlate to landing rates; that is, grass-water in 400meters buffer (GW_400) and high-trees in 100meter buffer distance (HT_100). It was concluded that the Cx. tritaeniorhynchus, the vector of JBE, could be detected in BOFP (well-urbanization area), and the environmental factor could affect not only the spatial distribution of JBE vector but also the mosquito landing rates in BOFP. Conclusions: The information achieved from this study could offer advice to people escaping from mosquito biting and provide useful information to prevent mosquito-borne diseases in Beijing, which means a lot to the public health of Beijing.

scholarly journals Zoonotic Tuberculosis in Humans: Control, Surveillance, and the One Health Approach

2019 ◽  
Vol 41 (1) ◽  
pp. 130-144
Author(s):  
Rodrigo Macedo Couto ◽  
Otavio T Ranzani ◽  
Eliseu Alves Waldman
Keyword(s):  
Low Income ◽  
One Health ◽  
Control Strategies ◽  
Diagnostic Methods ◽  
Surveillance Data ◽  
Control Measures ◽  
Low Income Countries ◽  
Effective Control ◽  
Surveillance Systems ◽  
And Control

Abstract Zoonotic tuberculosis is a reemerging infectious disease in high-income countries and a neglected one in low- and middle-income countries. Despite major advances in its control as a result of milk pasteurization, its global burden is unknown, especially due the lack of surveillance data. Additionally, very little is known about control strategies. The purpose of this review was to contextualize the current knowledge about the epidemiology of zoonotic tuberculosis and to describe the available evidence regarding surveillance and control strategies in high-, middle-, and low-income countries. We conducted this review enriched by a One Health perspective, encompassing its inherent multifaceted characteristics. We found that the burden of zoonotic tuberculosis is likely to be underreported worldwide, with higher incidence in low-income countries, where the surveillance systems are even more fragile. Together with the lack of specific political commitment, surveillance data is affected by lack of a case definition and limitations of diagnostic methods. Control measures were dependent on risk factors and varied greatly between countries. This review supports the claim that a One Health approach is the most valuable concept to build capable surveillance systems, resulting in effective control measures. The disease characteristics and suggestions to implement surveillance and control programs are discussed.

scholarly journals Integrated Approach to Malaria Control

2002 ◽  
Vol 15 (2) ◽  
pp. 278-293 ◽  
Author(s):  
Clive Shiff
Keyword(s):  
Malaria Control ◽  
Control Strategies ◽  
Integrated Approach ◽  
Global Strategy ◽  
Effective Control ◽  
Wide Range ◽  
Single Strategy ◽  
The 1960S ◽  
Effective Product ◽  
And Control

SUMMARY Malaria draws global attention in a cyclic manner, with interest and associated financing waxing and waning according to political and humanitarian concerns. Currently we are on an upswing, which should be carefully developed. Malaria parasites have been eliminated from Europe and North America through the use of residual insecticides and manipulation of environmental and ecological characteristics; however, in many tropical and some temperate areas the incidence of disease is increasing dramatically. Much of this increase results from a breakdown of effective control methods developed and implemented in the 1960s, but it has also occurred because of a lack of trained scientists and control specialists who live and work in the areas of endemic infection. Add to this the widespread resistance to the most effective antimalarial drug, chloroquine, developing resistance to other first-line drugs such as sulfadoxine-pyrimethamine, and resistance of certain vector species of mosquito to some of the previously effective insecticides and we have a crisis situation. Vaccine research has proceeded for over 30 years, but as yet there is no effective product, although research continues in many promising areas. A global strategy for malaria control has been accepted, but there are critics who suggest that the single strategy cannot confront the wide range of conditions in which malaria exists and that reliance on chemotherapy without proper control of drug usage and diagnosis will select for drug resistant parasites, thus exacerbating the problem. An integrated approach to control using vector control strategies based on the biology of the mosquito, the epidemiology of the parasite, and human behavior patterns is needed to prevent continued upsurge in malaria in the endemic areas.

scholarly journals Modeling Peste des Petits Ruminants (PPR) Disease Propagation and Control Strategies Using Memoryless State Transitions

2017 ◽  
Vol 1 (2) ◽  
pp. 90 ◽  
Author(s):  
Michael D. Mitchell ◽  
Walter E. Beyeler ◽  
Patrick Finley ◽  
Melissa Finley DVM, PhD
Keyword(s):  
Empirical Data ◽  
Large Scale ◽  
Control Strategies ◽  
Mitigation Strategies ◽  
Sensitivity Analyses ◽  
Effective Control ◽  
State Transitions ◽  
Morbidity Rate ◽  
Peste Des Petits Ruminants ◽  
And Control

<p><em>Peste des Petits Ruminants (PPR) is an infectious disease affecting goats and sheep. PPR has a mortality rate of 80% and a morbidity rate of 100% in naïve herds. This disease is currently of concern to Afghani goat and sheep herders as conditions in Afghanistan are conducive to the disease becoming an epidemic. PPR is similar to Rinderpest, but is not as well studied. There is a lack of empirical data on how the disease spreads or effective large-scale mitigation strategies. We developed a herd-level, event-driven model of PPR, using memoryless state transitions, to study how the virus propagates through a herd, and to identify effective control strategies for disparate herd configurations and environments. This model allows us to perform Sensitivity Analyses (SA) on environmental and disease parameters for which we do not have empirical data and to simulate the effectiveness of various control strategies. We find that reducing the amount of time from the identification of PPR in a herd to the vaccination of the herd will radically reduce the number of deaths that result from PPR. The goal of this model is to give policy makers a tool to develop effective containment strategies for managing outbreaks of PPR.</em></p>

scholarly journals Comparison between two types of control strategies for the coronavirus disease 2019 pandemic

2020 ◽  
Vol 14 (07) ◽  
pp. 696-698
Author(s):  
Xiaoyan Zhang ◽  
Yuxuan Wang
Keyword(s):  
Comparative Analysis ◽  
Severe Acute Respiratory Syndrome ◽  
Control Strategy ◽  
Prevention And Control ◽  
Control Strategies ◽  
Influenza Pandemic ◽  
Control Measures ◽  
Effective Control ◽  
Epidemic Control ◽  
And Control

Different countries have employed various strategies for controlling the coronavirus disease (COVID-19) pandemic because there is no consensus regarding effective control measures in the literature. Epidemic control strategies can be classified into two types based on their characteristics. The first type is the “severe acute respiratory syndrome (SARS)-like epidemic control strategy,” i.e., containment. The second type is the “influenza pandemic-like epidemic control strategy” (flu pandemic-like strategy), i.e., mitigation. This paper presents a comparative analysis on the prevention and control strategies for COVID-19 in different countries to provide a reference to control the further spread of the pandemic.

scholarly journals Cost-Effective Analysis of Control Strategies to Reduce the Prevalence of Cutaneous Leishmaniasis, Based on a Mathematical Model

2018 ◽  
Vol 23 (3) ◽  
pp. 38
Author(s):  
Dibyendu Biswas ◽  
Suman Dolai ◽  
Jahangir Chowdhury ◽  
Priti Roy ◽  
Ellina Grigorieva
Keyword(s):  
Mathematical Model ◽  
Cutaneous Leishmaniasis ◽  
Control Strategies ◽  
Cost Effective ◽  
Sand Fly ◽  
Effective Control ◽  
Theoretic Approach ◽  
Epidemic Disease ◽  
And Control

Leishmaniasis is a neglected tropical vector-borne epidemic disease, and its transmission is a complex process. Zoonotic transmission to humans or animals occurs through the bites of female Phlebotominae sand flies. Here, reservoir is considered as a major source of endemic pathogen pool for disease outbreak, and the role of more than one reservoir animal becomes indispensable. To study the role of the reservoir animals on disease dynamics, a mathematical model was constructed consisting of susceptible and infected populations of humans and two types of reservoir (animal) and vector populations, respectively. Our aim is to prevent the disease by applying a control theoretic approach, when more than one type of reservoir animal exists in the region. We use drugs like sodium stibogluconate and meglumine antimoniate to control the disease for humans and spray insecticide to control the sand fly population. Similarly, drugs are applied for infected reservoir animals of Types A and B. We calculated the cost-effectiveness of all possible combinations of the intervention and control policies. One of our findings is that the most cost-effective case for Leishmania control is the spray of insecticides for infected sand fly vector. Alternate strategic cases were compared to address the critical shortcomings of single strategic cases, and a range of control strategies were estimated for effective control and economical benefit of the overall control strategy. Our findings provide the most innovative techniques available for application to the successful eradication of cutaneous leishmaniasis in the future.

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