A population model for Noogoora Burr (Xanthium occidentale).

1983 ◽  
Vol 5 (2) ◽  
pp. 54 ◽  
Author(s):  
RJ Martin ◽  
JA Carnahan
Keyword(s):  
Biological Control ◽  
Large Scale ◽  
Control Measures ◽  
Weed Biological Control ◽  
Two Phase ◽  
Eastern Australia ◽  
Seed Reserves ◽  
Control Procedures ◽  
Grazing Lands ◽  
And Control

Noogoora burr (Xanthium occidentale), an annual species, is an important weed of sheep grazing lands in eastern Australia. This paper describes a model of Noogoora bun population dynamics which enables alternative management and control procedures to be simulated. The model is based on a two-phase life cycle with a long-lived overlapping population of seeds and short-lived non- overlapping populations of plants. The model takes into account changes in soil seed reserves due to germination, decay and dispersal. Density dependent processes affecting seed production were incorporated by using Shinozaki's reciprocal yield equation and measure- ments were made of seed losses due to granivory by birds and mice. Simple rainfall records were used to derive the model which was used to predict changes in seed populations in various environments. Theoretical seed populations were close to those actually observed. The model was also used to predict how particular control measures might affect population densities and the types of organisms which might be appropriate for biological control of the weed. Biological control appears to be the only possible means of controlling the large scale infestations of Noogoora burr in semi- arid areas where landholders have abandoned conventional control techniques.

scholarly journals Heterogeneity and effectiveness analysis of COVID-19 prevention and control in major cities in China through time-varying reproduction number estimation

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Qing Cheng ◽  
Zeyi Liu ◽  
Guangquan Cheng ◽  
Jincai Huang
Keyword(s):  
Prevention And Control ◽  
Large Scale ◽  
Reproduction Number ◽  
Correlation Method ◽  
Control Measures ◽  
Time Varying ◽  
Short Period ◽  
Significant Difference ◽  
Prevention And Control Measures ◽  
And Control

AbstractBeginning on December 31, 2019, the large-scale novel coronavirus disease 2019 (COVID-19) emerged in China. Tracking and analysing the heterogeneity and effectiveness of cities’ prevention and control of the COVID-19 epidemic is essential to design and adjust epidemic prevention and control measures. The number of newly confirmed cases in 25 of China’s most-affected cities for the COVID-19 epidemic from January 11 to February 10 was collected. The heterogeneity and effectiveness of these 25 cities’ prevention and control measures for COVID-19 were analysed by using an estimated time-varying reproduction number method and a serial correlation method. The results showed that the effective reproduction number (R) in 25 cities showed a downward trend overall, but there was a significant difference in the R change trends among cities, indicating that there was heterogeneity in the spread and control of COVID-19 in cities. Moreover, the COVID-19 control in 21 of 25 cities was effective, and the risk of infection decreased because their R had dropped below 1 by February 10, 2020. In contrast, the cities of Wuhan, Tianmen, Ezhou and Enshi still had difficulty effectively controlling the COVID-19 epidemic in a short period of time because their R was greater than 1.

Influences of Obstacles Installed in the Container on the Superheated Liquid Boiling

2012 ◽  
Vol 429 ◽  
pp. 62-66 ◽  
Author(s):  
Si Ning Chen
Keyword(s):  
Storage Tank ◽  
High Speed ◽  
Process Development ◽  
Control Measures ◽  
Movement Speed ◽  
Superheated Liquid ◽  
Two Phase ◽  
Microscopic Mechanism ◽  
Boiling Process ◽  
And Control

During the accident mechanism investigation of Boiling Liquid Expanding Vapor Explosion (BLEVE), numerous dada shows that overheated liquid explosive boiling is the main reason and driving force to cause accidents. Research on the micro-process of overheated liquid instant boiling in BLEVE as well as the microscopic mechanism to influence this process development under different device conditions is favorable to seek the preventive and control measures for this accident. In this paper, regarding the mesh obstacle provided inside the storage tank, high-speed camera technology has been utilized to shoot the boiling process during continuous leakage of the storage tank, and the influence of the obstacle on the overheated liquid boiling has been tested and analyzed. It is found out that the boiling process of overheated liquid has been delayed. When the bubbles are rising, the growth process has been suppressed, after passing the obstacle, the movement speed and volume has been decreased, and the upward expansion speed of two-phase flow has also been decreased.

The Biology and Control of the Sugar-cane Chafer Beetles in Tanganyika

1956 ◽  
Vol 47 (2) ◽  
pp. 377-397 ◽  
Author(s):  
W. F. Jepson
Keyword(s):  
Biological Control ◽  
Sugar Cane ◽  
Chemical Control ◽  
Parasite Species ◽  
Cultural Control ◽  
Control Measures ◽  
Mortality Factors ◽  
Resistant Varieties ◽  
And Control ◽  
Clemora Smithi

The principal pest of sugar-cane in northern Tanganyika is the Red Cane Beetle, Cochliotis melolonthoides (Gerst.) (Melolonthidae). Descriptions of adults and larvae of Cochliotis and of allied beetles found in the same area are given.The bionomics of Cochliotis have been studied in the field over two seasons. The life-cycle is annual with adult swarming in early October and a season of maximum larval damage in July–August.The intensity of infestation and the nature of the losses are discussed, and the mortality factors which act upon Cochliotis in nature are reviewed.Cultural control measures suggested include the deferment of planting until July to October, when larval activity has waned; introduction of quick-maturing varieties, mechanically cultivated so that long ratooning can be gradually eliminated; regulation of the water table by control of irrigation, and the trial of resistant varieties. The Mauritius varieties M. 134/32 and M. 165/38 are suggested in this connection.Biological control is discussed and a review of the parasite species that might possibly be introduced is made largely from the writer's Mauritius work on Clemora smithi (Arr.).Experiments in the chemical control of Cochliotis are described and the final recommendation is the application at planting of ½ lb. per 50 ft. of furrow of a BHC powder containing 2·5 per cent, of γ BHC. This practice has been adopted by the infested estate with successful results in virgins and first ratoons.Further work is suggested on the chemical protection of second and later ratoons by surface application of BHC or aldrin.

scholarly journals Reported Lead Levels in Different Environmental Matrices in Colombia

2021 ◽  
Vol 25 ◽  
Author(s):  
Carol Brigitte Hernández Rodríguez ◽  
Alvaro Martin Gutierrez-Malaxechebarria ◽  
Carlos Alfonso Zafra Mejía
Keyword(s):  
Policy Making ◽  
Large Scale ◽  
Control Measures ◽  
Scale Problem ◽  
Environmental Matrices ◽  
Exclusion Criteria ◽  
Target Values ◽  
Lead Levels ◽  
And Control ◽  
Qualitative Literature

Objective: The aim of this paper is to present a review of specific cases that reported lead concentrations in blood, objects, food, soil, bioindicators, air, and water in specific places in Colombia and evaluate the reported concentrations against target values. Materials and Methods: A systematic qualitative literature review of publications between 1995 and 2019 was done; using Boolean operators 1571 papers were identified, to which 3 inclusion and 4 exclusion criteria were applied. A total of 57 studies met the defined criteria. The reports in these studies were geo-localized and compared with acceptable values. Results and Discussion: Results suggest that lead is present in all environmental matrices, widely distributed in the Colombian territory, and that 72 % of the cases exceeded regulation limits. The percentage of noncompliance per environmental matrix was 89 % for blood samples, 71 % in food, 63 %, in soil, 89 % for bioindicators, 60 % for air, and 55 % for water. Conclusion: These results show that lead pollution is a large-scale problem in the country, more systematic studies are needed, and control measures, policy-making and regulatory updating should be pursued.

scholarly journals Heterogeneity and effectiveness analysis of COVID-19 prevention and control in major cities in China through time-varying reproduction numbers estimation

2020 ◽  
Author(s):  
Qing Cheng ◽  
Zeyi Liu ◽  
Guangquan Cheng ◽  
Jincai Huang
Keyword(s):  
Prevention And Control ◽  
Large Scale ◽  
Correlation Method ◽  
Control Measures ◽  
Time Varying ◽  
Reproduction Numbers ◽  
Short Period ◽  
Significant Difference ◽  
Novel Coronavirus ◽  
And Control

Abstract From December 31, 2019, a large-scale 2019 novel coronavirus disease (COVID-19) broke out in China. Tracking and analyzing the heterogeneity and effectiveness of cities’ prevention and control for COVID-19 epidemic is essential to design and adjust epidemic prevention and control. The number of newly infected cases in 25 China’s worst cities for COVID-19 epidemic from January 11 to February 10 was collected. The heterogeneity and effectiveness of these 25 cities’ prevention and control measures for COVID-19 were analyzed by using a estimate time-varying reproduction numbers method and a serial correlation method. The results shown that the effective reproduction number (R) in 25 cities showed a downward trend as a whole, but there was a significant difference in the R change trends among cities indicating that there was heterogeneity in the spread and control of COVID-19 in cities. Moreover, the COVID-19 control in 21 of 25 cities were effective and the risk of infection was decreasing due to their R had dropped below 1 on February 10, 2020 and the average decline of R in the past 5 days was greater than 0, while cities of Wuhan, Tianmen, Ezhou and Enshi were still difficult to effectively control the COVID-19 epidemic in a short period of time because their R was also greater than 1.

scholarly journals Preliminary Analysis of African Swine Fever Virus Carriage and Transmission by Mosquitoes

2021 ◽  
Author(s):  
Weiyun Qin ◽  
Zhongcheng Gao ◽  
Shenglong Wu ◽  
Wenbin Bao
Keyword(s):  
Large Scale ◽  
Mosquito Control ◽  
African Swine Fever Virus ◽  
African Swine Fever ◽  
Fever Virus ◽  
Qpcr Analysis ◽  
Pig Farms ◽  
Negative Cycle ◽  
Control Procedures ◽  
And Control

Abstract BackgroundMosquitoes are important insect vectors, but whether they can carry and transmit African swine fever virus (ASFV) in large-scale pig farms in China is unknown. ResultsIn this study, probe qPCR analysis was performed on mosquitoes from five pig farms with ASF virus (ASFV). Analysis of ASFV in 463 mosquitoes yielded negative cycle threshold (CT) value), and detection remained negative after mixing samples from all five pig farms. ConclusionsTherefore, mosquitoes appear unlikely to transmit ASFV, and pose little threat to large-scale pig farms. Thus, farms should continue to follow normal mosquito control procedures when formulating strategies for the prevention and control of ASF.

scholarly journals The extent of commitment of Jordanian banks to apply internal control procedures to detect and prevent money laundering operations: مدى التزام المصارف الأردنية بتطبيق إجراءات الرقابة الداخلية لاكتشاف ومنع عمليات غسيل الأموال

2019 ◽  
Vol 3 (12) ◽  
Author(s):  
Reem Okab Al-kasswna
Keyword(s):  
Money Laundering ◽  
Internal Control ◽  
Theoretical Framework ◽  
Control Measures ◽  
External Auditors ◽  
Study Population ◽  
Control Procedures ◽  
And Control ◽  
High Degree

    This study aims at demonstrating the role and importance of internal control measures in combating money laundering operations in Jordanian banks through the statement of internal control procedures that contribute to the discovery of money laundering operations. The study shows the role of internal control procedures in detecting money laundering through electronic programs, and the existence of a system for keeping files and records Money laundering The researcher used the descriptive analytical approach, which is based on the collection of information on the main elements of the study, analysis and interpretation in order to build the theoretical framework for them based on the audit literature and instructions of the Central Bank and commercial banks on internal control of money laundering operations, which dealt with the subject of internal control systems, and anti-laundering law Funds and control measures related to combating money laundering. Through the theoretical framework, a questionnaire was designed on the application of internal control procedures and its relation to combating money laundering operations and distribution to the study population which includes 14 Jordanian banks, with 3 questionnaires for each bank for both internal and external auditors and head of anti-money laundering unit in a bank. The study concluded that it is important to apply the internal control procedures to a high degree among respondents to the questionnaire in preventing and detecting money laundering operations in Jordanian banks    

scholarly journals Overcoming Current and Preventing Future Nosocomial Outbreaks during the COVID-19 Pandemic: Lessons Learned at Three Hospitals in Japan

2021 ◽  
Vol 18 (19) ◽  
pp. 10226
Author(s):  
Makiko Komasawa ◽  
Myo Nyein Aung ◽  
Kiyoko Saito ◽  
Mitsuo Isono ◽  
Go Tanaka ◽  
...  
Keyword(s):  
Infection Control ◽  
Large Scale ◽  
Practical Knowledge ◽  
Care Delivery ◽  
Lessons Learned ◽  
Control Measures ◽  
Infection Prevention And Control ◽  
Infection Control Measures ◽  
Health Care Delivery Systems ◽  
And Control

Hospitals are increasingly challenged by nosocomial infection (NI) outbreaks during the ongoing coronavirus disease 2019 (COVID-19) pandemic. Although standardized guidelines and manuals regarding infection prevention and control (IPC) measures are available worldwide, case-studies conducted at specified hospitals that are required to cope with real settings are limited. In this study, we analyzed three hospitals in Japan where large-scale NI outbreaks occurred for hints on how to prevent NI outbreaks. We reviewed openly available information from each hospital and analyzed it applying a three domain framework: operation management; identification of infection status; and infection control measures. We learned that despite having authorized infection control teams and using existing standardized IPC measures, SARS-CoV-2 may still enter hospitals. Early detection of suspected cases and confirmation by PCR test, carefully dealing with staff-to-staff transmission were the most essential factors to prevent NI outbreaks. It was also suggested that ordinary training on IPC for staff does not always provide enough practical knowledge and skills; in such cases external technical and operational supports are crucial. It is expected that our results will provide insights into preventing NI outbreaks of COVID-19, and contribute to mitigate the damage to health care delivery systems in various countries.

scholarly journals Preliminary analysis of whether mosquitoes can carry and transmit African swine fever

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Weiyun Qin ◽  
Zhongcheng Gao ◽  
Shenglong Wu ◽  
Wenbin Bao
Keyword(s):  
Preliminary Analysis ◽  
Large Scale ◽  
Mosquito Control ◽  
African Swine Fever Virus ◽  
African Swine Fever ◽  
Qpcr Analysis ◽  
Pig Farms ◽  
Negative Cycle ◽  
Control Procedures ◽  
And Control

Abstract Background Mosquitoes are important insect vectors, but whether they can carry and transmit African swine fever virus (ASFV) in large-scale pig farms in China is unknown. Results In this study, probe-based qPCR analysis was performed on mosquitoes from five pig farms with ASF virus (ASFV). Analysis of ASFV in 463 mosquitoes yielded negative cycle threshold (CT) value), and detection remained negative after mixing samples from all five pig farms. Conclusions Therefore, mosquitoes appear unlikely to transmit ASFV, and pose little threat to large-scale pig farms. Thus, farms should continue to follow normal mosquito control procedures when formulating strategies for the prevention and control of ASF.

scholarly journals Wet climate and transportation routes accelerate spread of human plague

2014 ◽  
Vol 281 (1780) ◽  
pp. 20133159 ◽  
Author(s):  
Lei Xu ◽  
Leif Chr. Stige ◽  
Kyrre Linné Kausrud ◽  
Tamara Ben Ari ◽  
Shuchun Wang ◽  
...  
Keyword(s):  
Large Scale ◽  
Control Measures ◽  
Long Distance ◽  
Quantitative Analyses ◽  
Novel Method ◽  
Wet Climate ◽  
Prevention And Control Measures ◽  
And Control ◽  
Transportation Routes ◽  
Transmission Speed

Currently, large-scale transmissions of infectious diseases are becoming more closely associated with accelerated globalization and climate change, but quantitative analyses are still rare. By using an extensive dataset consisting of date and location of cases for the third plague pandemic from 1772 to 1964 in China and a novel method (nearest neighbour approach) which deals with both short- and long-distance transmissions, we found the presence of major roads, rivers and coastline accelerated the spread of plague and shaped the transmission patterns. We found that plague spread velocity was positively associated with wet conditions (measured by an index of drought and flood events) in China, probably due to flood-driven transmission by people or rodents. Our study provides new insights on transmission patterns and possible mechanisms behind variability in transmission speed, with implications for prevention and control measures. The methodology may also be applicable to studies of disease dynamics or species movement in other systems.

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