scholarly journals Standard Area Diagrams for Aiding Severity Estimation: Scientometrics, Pathosystems, and Methodological Trends in the Last 25 Years

2017 ◽  
Vol 107 (10) ◽  
pp. 1161-1174 ◽  
Author(s):  
Emerson M. Del Ponte ◽  
Sarah J. Pethybridge ◽  
Clive H. Bock ◽  
Sami J. Michereff ◽  
Franklin J. Machado ◽  
...  

Standard area diagrams (SAD) have long been used as a tool to aid the estimation of plant disease severity, an essential variable in phytopathometry. Formal validation of SAD was not considered prior to the early 1990s, when considerable effort began to be invested developing SAD and assessing their value for improving accuracy of estimates of disease severity in many pathosystems. Peer-reviewed literature post-1990 was identified, selected, and cataloged in bibliographic software for further scrutiny and extraction of scientometric, pathosystem-related, and methodological-related data. In total, 105 studies (127 SAD) were found and authored by 327 researchers from 10 countries, mainly from Brazil. The six most prolific authors published at least seven studies. The scientific impact of a SAD article, based on annual citations after publication year, was affected by disease significance, the journal’s impact factor, and methodological innovation. The reviewed SAD encompassed 48 crops and 103 unique diseases across a range of plant organs. Severity was quantified largely by image analysis software such as QUANT, APS-Assess, or a LI-COR leaf area meter. The most typical SAD comprised five to eight black-and-white drawings of leaf diagrams, with severity increasing nonlinearly. However, there was a trend toward using true-color photographs or stylized representations in a range of color combinations and more linear (equally spaced) increments of severity. A two-step SAD validation approach was used in 78 of 105 studies for which linear regression was the preferred method but a trend toward using Lin’s correlation concordance analysis and hypothesis tests to detect the effect of SAD on accuracy was apparent. Reliability measures, when obtained, mainly considered variation among rather than within raters. The implications of the findings and knowledge gaps are discussed. A list of best practices for designing and implementing SAD and a website called SADBank for hosting SAD research data are proposed.

Author(s):  
Reva Nagi ◽  
Sanjaya Shankar Tripathy

The timely detection of the infection in plants and its severity is a major concern for the farmers. Although various techniques have been employed to identify and estimate the severity of infection, they generally use a fixed threshold to segment the infected areas from the leaf image. Such methods define the participation of a pixel, as part of the infected area, in the form of a classical or crisp set. Use of fuzzy logic in feature extraction, grading the disease post identification, and estimating the disease severity are seen as rapidly growing techniques. Using fuzzy logic, the infected area is calculated by considering the degree of contribution provided by neighboring pixels to the current pixel. The severity estimation is performed on the basis of the infected area and the number of lesions in the leaf image. Depending on the amount of infection, severity has been classified into early, middle, later, and advanced stage. The proposed technique will help the farmers to identify the disease class at an early stage.


2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Clive H. Bock ◽  
Jayme G. A. Barbedo ◽  
Emerson M. Del Ponte ◽  
David Bohnenkamp ◽  
Anne-Katrin Mahlein

1996 ◽  
Vol 4 (5) ◽  
pp. 16-17
Author(s):  
Richard S. Brown

Having shopped for an inexpensive but powerful digital imaging system for the last four years, I have finally found a device that will satisfy even the most frugal budget. The Snappy Video Snapshot by Play, Incl, is a 24-bit true color frame grabber that plugs into your PC printer port. After plugging the Snappy device into your printer port (Figure 1) and spending approximately six minutes loading the Snappy software provided, you can connect a color or black and white camera, VCR, or television set and capture your first digital image. Because the device plugs into a printer port, it is completely portable. A switch box is needed if you will be changing between digital image acquisition and printing tasks frequently.


2014 ◽  
Vol 14 (1) ◽  
pp. 1-12
Author(s):  
Didik Ardiyanto ◽  
Bambang Hari Purwoto

Kompresi citra merupakan suatu teknik yang digunakan untuk mengurangi biaya penyimpanan dan transmisi. Pemampatan atau kompresi citra merupakan suatu metode yang sangat bermanfaat bagi perkembangan citra digital. Dengan kompresi, data citra digital yang ukurannya besar, dapat dikompres sehingga mempunyai ukuran yang lebih kecil. Program kompresi citra dengan metode delta modulation ini, dibuat dengan GUI dan source coding. Dengan menerapkan fungsi dari Dmsig untuk pengolahan sinyal, maka didapatkan rumus untuk mengkompres gambar yang dipengaruhi oleh step size dan ukuran gambar tersebut. Kelebihan dari teknik Delta Modulation adalah dapat mengkompres gambar grayscale, black and white dan true color. Hasil gambar yang sudah dikompres menunjukkan bahwa metode ini baik untuk menghasilkan gambar dengan output berformat jpg,png dan tiff. Kualitas gambar yang paling baik dari hasil kompresi delta modulation yaitu gambar berformat jpg. Untuk tingkat kompresi yang paling bagus juga ada pada gambar berformat jpg, ini diambil berdasarkan nilai MSE dan PSNR yang di hitung pada gambar hasil kompresi. Tingkat kompresi dengan delta modulation termasuk tinggi karena masuk ke lossy compression.


2020 ◽  
Vol 8 (7_suppl6) ◽  
pp. 2325967120S0045
Author(s):  
Christa Wentt ◽  
Morgan Jones ◽  
Greg Strnad ◽  
Isaac Briskin ◽  
Kurt Spindler ◽  
...  

Objectives: Several clinical studies have outlined differences in clinical outcomes and access to care when controlling for race. No published clinical study has ever investigated healthcare disparities between Black and White patients presenting for sports medicine knee surgery. The purpose of this study is to determine if the racial disparities described in the literature for total joint arthroplasty and spine surgery are also preset in patients presenting for sports medicine knee surgery. Our first hypothesis is that Black patients presenting for sports medicine knee surgery have worse baseline patient-reported quality of life scores, pain, and function compared to White patients. Our second hypothesis is that Black patients have more disease severity at the time of surgery compared to their White counterparts. Methods: We prospectively collected patient-reported outcomes (PROs), disease severity, and treatment utilizing the [BLINDED DATABASE]. Patient race, body mass index (BMI) and insurance were retrospectively collected from the electronic medical record (EMR). We included consecutive patients undergoing both knee arthroscopy (partial meniscectomy) and anterior cruciate ligament (ACL) reconstruction surgery. We excluded patients undergoing other chondral replacement or complex ligamentous procedures (e.g. MPFL reconstruction, multiligamentous knee surgery, etc). Univariate ("unadjusted") analysis was utilized to compare differences between groups with ANOVA, Kruskal Wallis Testing and Pearson’s Chi-square testing. Subsequently, a multivariate analysis model was constructed to control for confounding variables within Black patients vs White patients in order to evaluate for racial disparities in baseline PROs and disease severity. All testing was considered significant at the 5% level. Results: We enrolled a total of 4,557 patients for this study. In the arthroscopy group (APM) we enrolled 3086 total patients. In this group there were 2593 White patients and 408 Black patients. Eighty-five patients identified as “Other”. In the ACL reconstruction (ACLR) group there were 1471 patients. In this group 1197 patients identified as White, 202 patients identified as Black and 72 patients identified as “Other”. Univariate analysis in the APM group demonstrated racial disparities in certain key metrics. BMI was worse in Black patients (32.4) compared to White patients (30.3) (p < 0.001). Both KOOS pain (41.7 versus 47.2; p < 0.001) and KOOS function (51.5 versus 58.0; p < 0.001) were worse in Black patients compared to White patients. A larger portion of Black patients were current smokers compared to White patients (16.% versus 10%; p < 0.001). Baseline VR12 scores were also lower in Black versus White patients (48.4 versus 55.9, p 0.001). Multivariate analysis revealed no racial disparities for any baseline patient-reported outcome measure (pain, function, or quality of life). This is a result of Black patients being more likely to present with higher BMI, current smoker status, fewer years of formal education, and Medicaid insurance. No significant differences between Black and White patients were noted with respect to disease severity (intraoperative pathology; i.e. worse chondral grade, compartments involved, meniscus tear severity). Our ACLR group demonstrated similar findings on univariate analysis with Black patients more likely to have Medicare/Medicaid than commercial insurance, a higher BMI, smoking history and a lower VR12 score compared to White patients. Linear regression analysis demonstrates that age, gender (female worse), BMI, years of education, smoking status and insurance are all significant drivers of outcome for KOOS pain. With respect to additional intra-articular pathology at the time of ACL tear, female sex and increasing years of education were at an increased odds of having a complete meniscal tear. Neither race or insurance status were significant drivers of concomitant intra-articular findings in ACL tear patients. Conclusions: There is no statistically significant racial disparity in baseline patient reported outcomes with respect to patients presenting for sports medicine knee surgery when controlling for important covariates. Black patients did present with worse subjective KOOS knee pain and functional scores, however, when possible confounding variables were controlled for in a multivariable analysis, there was no difference between the White and Black cohorts. The results of this study show that there may be modifiable risk factors that affect outcomes of patients irrespective of racial background. Addressing factors such as BMI, smoking status and healthcare literacy may help to improve outcomes for patients. Further research into interventions to correct these risk factors is needed.


2015 ◽  
Vol 65 (4) ◽  
pp. 523-535 ◽  
Author(s):  
K. S. Chiang ◽  
C. H. Bock ◽  
M. El Jarroudi ◽  
P. Delfosse ◽  
I. H. Lee ◽  
...  

Author(s):  
Peter J. Schüffler ◽  
Dwarikanath Mahapatra ◽  
Robiel Naziroglu ◽  
Zhang Li ◽  
Carl A. J. Puylaert ◽  
...  

2019 ◽  
Vol 1 (2) ◽  
pp. 205-219 ◽  
Author(s):  
Malusi Sibiya ◽  
Mbuyu Sumbwanyambe

This paper explains a proposed algorithm for severity estimation of plant leaf diseases by using maize leaf diseased samples. In the literature, a number of researchers have addressed the problem of plant leaf disease severity estimation, but a few, such as Sannakki et al., have used fuzzy logic to determine the severity estimations of the plant leaf diseases. The present paper aims to update the current algorithm used in the “Leaf Doctor” application that is used to estimate the severities of the plant leaf diseases by introducing the benefits of fuzzy logic decision making rules. This method will contribute to precision agriculture technology as it introduces an algorithm that may be embedded in smartphone devices and used in applications, such as a “Leaf Doctor” application. The applications designed based on the algorithm proposed in this study will help users who are inexperienced and not plant pathologists understand the level of the estimated disease severity. The use of fuzzy logic inference rules along with image segmentation determines the novelty of this approach in comparison with the available methods in the literature.


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