Phyllachora maydis Ascospore Release and Germination from Overwintered Corn Residue

Tar spot of corn, caused by Phyllachora maydis, has been reported in several upper Midwest states in the United States. This has led to expanded efforts to more thoroughly understand the biology of P. maydis and the epidemiology of tar spot. This study determined the potential for P. maydis ascospore release and germination from overwintered P. maydis-infected corn residues from various locations in the upper Midwest. Corn residue samples collected in the spring of 2019 from 12 fields in four states were examined. Ascospore release and germination were observed in all residue samples collected. The mean total number of ascospores released per milliliter of water ranged from 3.6 × 103 to 4.8 × 106 after 4-h incubation and 3.7 × 103 to 4.4 × 106 after 24-h incubation. The mean percent spore germination ranged from 0.7 to 24.1% after 4-h incubation and 2.4 to 24.9% after 24-h incubation. There was a significant inverse relationship between total numbers of ascospores released and the percent germination of the ascospores. Samples from Illinois consistently yielded the greatest total ascospore release but were also consistently among the samples with the lowest percent ascospore germination. Samples from Wisconsin and Indiana were among the lowest for total ascospore numbers but were among the highest for total ascospore germination. These findings provide evidence that P. maydis can overwinter in multiple areas of the upper Midwest. Future research should focus on reducing infested corn residue to reduce initial infection by P. maydis.

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Heavy metals content in soils and cocoa tissues in Magdalena department Colombia: emphasis in cadmium

ENTRAMADO ◽

10.18041/1900-3803/entramado.2.6753 ◽

2020 ◽

Vol 16 (2) ◽

pp. 298-310

Author(s):

Sonia Esperanza Aguirre-Forero ◽

Nelson Virgilio Piraneque-Gambasica ◽

José Rafael Vásquez-Polo

Keyword(s):

Environmental Protection Agency ◽

Potential Problem ◽

The United States ◽

Future Research ◽

The European Union ◽

Tropical Asia ◽

Cr Content ◽

Foliage Leaf ◽

The Mean ◽

Theobroma Cacao L

Cocoa (Theobroma cacao L.) is a species originating from the humid tropics. Over 70,000 km2 worldwide is dedicated to growing cocoa, and approximately 30% of its global production is concentrated in the equatorial regions of Central and South America, the Antilles and tropical Asia. The demand for cocoa is growing significantly, but the presence of cadmium (Cd) in the species is a potential problem limiting its commercialization. The present study determined the Cd, Ni, Pb and Cr content in two cocoa-producing regions in northern Colombia. Foliage (leaf, bean and shell) and soil were analyzed. The mean Ni, Pb and Cr content in the plant tissue did not exceed the maximum permissible limits set by the United States Environmental Protection Agency (EPA). The mean Cd content in the beans was 0.51 mg kg-1 in region 1 and 0.66 mg kg-1 in region 2, which are considered risky per reports from the European Union and restrict the product’s export. These results serve as a reference for future research on cocoa.

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Tar Spot: An Understudied Disease Threatening Corn Production in the Americas

Plant Disease ◽

10.1094/pdis-02-20-0449-fe ◽

2020 ◽

Vol 104 (10) ◽

pp. 2541-2550

Author(s):

J. Valle-Torres ◽

T. J. Ross ◽

D. Plewa ◽

M. C. Avellaneda ◽

J. Check ◽

...

Keyword(s):

Latin American ◽

Management Strategies ◽

The United States ◽

Epidemiological Studies ◽

Future Research ◽

Corn Production ◽

Tar Spot ◽

Significant Yield ◽

Obligate Pathogen ◽

Latin American Countries

Tar spot of corn has been a major foliar disease in several Latin American countries since 1904. In 2015, tar spot was first documented in the United States and has led to significant yield losses of approximately 4.5 million t. Tar spot is caused by an obligate pathogen, Phyllachora maydis, and thus requires a living host to grow and reproduce. Due to its obligate nature, biological and epidemiological studies are limited and impact of disease in corn production has been understudied. Here we present the current literature and gaps in knowledge of tar spot of corn in the Americas, its etiology, distribution, impact and known management strategies as a resource for understanding the pathosystem. This will in turn guide current and future research and aid in the development of effective management strategies for this disease.

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Abstract 248: National Trends in Utilization and Economic Outcomes of Catheter Ablation for Atrial Fibrillation in the United States 2003-2008

Circulation Cardiovascular Quality and Outcomes ◽

10.1161/circoutcomes.7.suppl_1.248 ◽

2014 ◽

Vol 7 (suppl_1) ◽

Author(s):

Anant Mandawat ◽

Aditya Mandawat ◽

Rama Mandawat ◽

Mahendra Mandawat

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Clinical Outcomes ◽

The United States ◽

Economic Outcomes ◽

Future Research ◽

The Us ◽

Comorbidity Index ◽

The Mean ◽

National Trends

Introduction: Data on the utilization and economic outcomes of catheter ablation in atrial fibrillation (AF) is scarce, limiting the ability to make informed policy decisions. Hypothesis: We hypothesized that the number of catheter ablations for AF increased while length of stay and charges decreased. Methods: Patients > 18 years undergoing catheter ablation for AF were selected in the 2003-2008 HCUP-Nationwide Inpatient Sample, the largest all-payor inpatient database in the US. Patient demographic and clinical variables, including a Charlson comorbidity index, as well as hospital characteristics were analyzed. We calculated trends in rates of utilization, economic (mean LOS and total inflation-adjusted charges) and clinical (in-hospital mortality and in-hospital complications, defined using ICD-9 codes) outcomes using χ 2 , Mantel-Haenszel tests, and analysis of variance (ANOVA). Results: There were 40,145 admissions for catheter ablation for AF (mean age 60.01 years (SD 11.74; Range 18-98). The number of ablations increased by nearly 300% between 2003 and 2008 (Table). A comparison of use rates between 2003-2005 (early) vs 2006-2008 (late) showed a higher utilization among patients aged 65-79 (27.3% vs 34.0%), those with moderate comorbidities (30.3% vs 46.3%), and medium-sized hospitals (9.8% vs 19.7%), all p<0.001. During the study period, the mean LOS decreased by 30% while inflation-adjusted charges increased by 25% (Table). There was no significant change in clinical outcomes (Table). Conclusions: The number of catheter ablations for AF has increased rapidly. Although the procedure is being applied to a broader patient population and being performed in smaller-sized hospitals, LOS has decreased and clinical outcomes are stable. Factors contributing to and strategies to limit rising charges for this expanding procedure are important areas of future research.

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Virulence Frequencies in Oat Crown Rust in the United States from 2001 Through 2005

Plant Disease ◽

10.1094/pdis-92-3-0379 ◽

2008 ◽

Vol 92 (3) ◽

pp. 379-384 ◽

Cited By ~ 27

Author(s):

M. L. Carson

Keyword(s):

United States ◽

The United States ◽

Crown Rust ◽

Upper Midwest ◽

Oat Crown Rust ◽

Oat Cultivars ◽

The Mean ◽

Production Areas ◽

The U.S ◽

Virulence Diversity

In all, 680 single-pustule isolates of the oat crown rust pathogen, Puccinia coronata f. sp. avenae, were collected from cultivated and wild oat (Avena sativa and A. fatua, respectively) in the major oat-production areas of the United States from 2001 through 2005. They were tested for virulence on seedlings of differential oat lines in the greenhouse. In all, 171 races were found among the 357 isolates from the winter oat region of the United States, whereas 212 races were found among 323 isolates from the spring oat region. The crown rust population derived from winter oat in the southern United States was distinct from the spring oat population in the upper Midwest, although there was no virulence unique to either population. Virulence to Pc48 and Pc52 increased significantly in both regions during 2001 to 2005. Virulence to Pc59 increased and virulence to Pc53 decreased in the winter oat region during the same period. Many of the virulence associations previously reported in the U.S. oat crown rust population in the early 1990s also were found in both regions in this survey. Associations between virulence to the Pc genes were predominately positive in both regions; however, both positive and negative associations occurred more frequently in the winter oat region. Much of the virulence diversity in the oat crown rust population in the United States can be related to the deployment of resistance genes in commercial oat cultivars and virulence associations existing in the oat crown rust population. The mean virulence of the U.S. populations of crown rust continued to increase from 2001 to 2005. Genes for crown rust resistance derived from A. sterilis appear to be rapidly defeated, as has happened to Pc genes from A. sativa.

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An Observation of Corn Tar Spot Dispersal from Agricultural Fields to an Isolated Urban Plot

Plant Health Progress ◽

10.1094/php-10-20-0082-br ◽

2020 ◽

Author(s):

Nathan M. Kleczewski ◽

Norman D. Bowman

Keyword(s):

United States ◽

Latin America ◽

The United States ◽

Urban Setting ◽

Urban Site ◽

Agricultural Fields ◽

Rapid Progression ◽

Tar Spot ◽

Corn Residue ◽

Published Research

Tar spot of corn is a fairly new disease to the United States, and since its introduction in 2015 it has spread to over 310 counties across nine states. Little is understood of the biology and epidemiology of the causative agent of tar spot of corn, Phyllachora maydis. Published research from Latin America indicates that spores can only travel a distance of 75 m; however, rapid progression and spread in the United States, in addition to widespread observations of top-down infection, indicate distal dispersal is likely more important. We observed an isolated plot of decorative corn in an urban setting, isolated from agricultural fields. We assessed nearby fields for crop, tar spot, cropping history, and distance from the urban site. Based on our observations, the propagules infecting the urban plot arrived from at least 560 m if from corn residue, and from at least 1,249 m if from active infections from nearby corn. Although this observation is not replicated, it does indicate that dispersal values from Latin America may not reflect the potential dispersion in Midwest topographies.

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The association of urine osmolality with decreased kidney function and/or albuminuria in the United States

BMC Nephrology ◽

10.1186/s12882-021-02478-9 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Boonsong K. Kitiwan ◽

Sarinnapha M. Vasunilashorn ◽

Heather J. Baer ◽

Kenneth Mukamal ◽

Stephen P. Juraschek

Keyword(s):

Kidney Function ◽

Positive Association ◽

Urine Osmolality ◽

The United States ◽

Sensitivity Analyses ◽

Future Research ◽

Cross Sectional ◽

Lower Egfr ◽

The Mean ◽

The Relationship

Abstract Background Decreased kidney function is commonly caused by hypovolemia. When hypovolemic, the kidney reabsorbs water resulting in concentrated urine. Osmolality is a measure of urine concentration which is more objective than self-reported fluid intake. It has a positive association with hypovolemia. However, it remains controversial whether osmolality is associated with decreased kidney function and/or albuminuria. Methods We conducted a cross-sectional analysis of the 2009–2012 National Health and Nutrition Examination Survey, a standardized survey in the U.S. population. Participants aged 18–70 years old with random urine osmolality were included. Osmolality was categorized as quartiles. Decreased kidney function was defined by estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73m2 and albuminuria was defined by albumin-to-creatinine ratio ≥ 30 mg/gm. We performed multivariable regression via four sequential models. Results Our study sample included 7,373 participants. The mean age was 42.9 ± 0.4 years. Overall, 51.4% were male and 67.3% were white. The mean osmolality was 603.8 mOsm/kg and 629.1 mOsm/kg in those with and without decreased eGFR and/or albuminuria, respectively. The number of cases was 610 (6.7%). The prevalence from the lowest to highest quartiles of osmolality was 116 (6.2%), 213 (8.6%), 179 (7.5%), and 102 (4.3%), respectively (p-value for trend = 0.02). The relationship between osmolality and eGFR appeared nonlinear. After adjustment for demographic, social, cardiovascular, and dietary risk factors, there was no significant association of osmolality quartiles with decreased eGFR and/or albuminuria (odds ratio [OR] 0.77, 95% confidence interval [CI] 0.56, 1.07). In sensitivity analyses, osmolality ≥ 500 mOsm/kg was associated with lower eGFR (adjusted ß -1.13, 95% CI -1.98, -0.28). In pre-specified subgroup analyses, osmolality had a statistically significant negative correlation with eGFR among individuals with eGFR ≥ 60 mL/min/1.73m2, but a positive correlation among those with eGFR < 60 mL/min/1.73m2 (adjusted ß -0.19, 95% CI -0.36, -0.01 versus adjusted ß 0.50, 95% CI 0.05, 0.96; p-value for interaction = 0.016). Conclusions Higher osmolality was significantly associated with lower eGFR among adults with eGFR ≥ 60 mL/min/1.73m2 Future research should examine the relationship between osmolality and change in kidney function over time among adults with normal eGFR.

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Refining Evidence-Based Treatments for Late-Life Depression

GeroPsych ◽

10.1024/1662-9647/a000127 ◽

2015 ◽

Vol 28 (2) ◽

pp. 67-76

Author(s):

Grace C. Niu ◽

Patricia A. Arean

Keyword(s):

Older Adults ◽

Mental Illness ◽

Brain Plasticity ◽

Late Life ◽

Aging Population ◽

The United States ◽

Future Research ◽

Evidence Based ◽

Late Life Depression ◽

Evidence Based Treatments

The recent increase in the aging population, specifically in the United States, has raised concerns regarding treatment for mental illness among older adults. Late-life depression (LLD) is a complex condition that has become widespread among the aging population. Despite the availability of behavioral interventions and psychotherapies, few depressed older adults actually receive treatment. In this paper we review the research on refining treatments for LLD. We first identify evidence-based treatments (EBTs) for LLD and the problems associated with efficacy and dissemination, then review approaches to conceptualizing mental illness, specifically concepts related to brain plasticity and the Research Domain Criteria (RDoc). Finally, we introduce ENGAGE as a streamlined treatment for LLD and discuss implications for future research.

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Relation of Statistically Significant, Abnormal, and Typical WAIS-R VIQ-PIQ Discrepancies to Full Scale IQs

European Journal of Psychological Assessment ◽

10.1027//1015-5759.16.2.107 ◽

2000 ◽

Vol 16 (2) ◽

pp. 107-114 ◽

Cited By ~ 3

Author(s):

Louis M. Hsu ◽

Judy Hayman ◽

Judith Koch ◽

Debbie Mandell

Keyword(s):

Graphical Method ◽

The United States ◽

Full Scale ◽

True Score ◽

Absolute Value ◽

Normative Population ◽

The Us ◽

The Mean ◽

And Performance ◽

Quadratic Models

Summary: In the United States' normative population for the WAIS-R, differences (Ds) between persons' verbal and performance IQs (VIQs and PIQs) tend to increase with an increase in full scale IQs (FSIQs). This suggests that norm-referenced interpretations of Ds should take FSIQs into account. Two new graphs are presented to facilitate this type of interpretation. One of these graphs estimates the mean of absolute values of D (called typical D) at each FSIQ level of the US normative population. The other graph estimates the absolute value of D that is exceeded only 5% of the time (called abnormal D) at each FSIQ level of this population. A graph for the identification of conventional “statistically significant Ds” (also called “reliable Ds”) is also presented. A reliable D is defined in the context of classical true score theory as an absolute D that is unlikely (p < .05) to be exceeded by a person whose true VIQ and PIQ are equal. As conventionally defined reliable Ds do not depend on the FSIQ. The graphs of typical and abnormal Ds are based on quadratic models of the relation of sizes of Ds to FSIQs. These models are generalizations of models described in Hsu (1996) . The new graphical method of identifying Abnormal Ds is compared to the conventional Payne-Jones method of identifying these Ds. Implications of the three juxtaposed graphs for the interpretation of VIQ-PIQ differences are discussed.

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A Silenced Population

Crisis ◽

10.1027/0227-5910/a000470 ◽

2017 ◽

Vol 38 (6) ◽

pp. 433-442 ◽

Cited By ~ 1

Author(s):

Kim Gryglewicz ◽

Melanie Bozzay ◽

Brittany Arthur-Jordon ◽

Gabriela D. Romero ◽

Melissa Witmeier ◽

...

Keyword(s):

At Risk ◽

Depressive Symptomatology ◽

The United States ◽

Future Research ◽

At Risk Youth ◽

Peer Relationship ◽

Student Records ◽

Cross Sectional ◽

Increased Risk ◽

Method Student

Abstract. Background: Given challenges that exceed the normal developmental requirements of adolescence, deaf and hard-of-hearing (DHH) youth are believed to be at elevated risk for engaging in suicide-related behavior (SRB). Unfortunately, little is known about the mechanisms that put these youth potentially at risk. Aims: To determine whether peer relationship difficulties are related to increased risk of SRB in DHH youth. Method: Student records (n = 74) were retrieved from an accredited educational center for deaf and blind students in the United States. Results: Peer relationship difficulties were found to be significantly associated with engagement in SRB but not when accounting for depressive symptomatology. Limitations: The restricted sample limits generalizability. Conclusions regarding risk causation cannot be made due to the cross-sectional nature of the study. Conclusion: These results suggest the need for future research that examines the mechanisms of the relationship between peer relationship difficulties, depression, and suicide risk in DHH youth and potential preventive interventions to ameliorate the risks for these at-risk youth.

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Dormancy-breaking Studies on Echinacea angustifolia

HortScience ◽

10.21273/hortsci.33.3.456f ◽

1998 ◽

Vol 33 (3) ◽

pp. 456f-457 ◽

Cited By ~ 1

Author(s):

Ali O. Sari ◽

Mario R. Morales ◽

James E. Simon

Keyword(s):

Native Americans ◽

Seed Germination ◽

Tap Water ◽

The United States ◽

Market Demand ◽

Dormancy Breaking ◽

Echinacea Angustifolia ◽

Native Populations ◽

Percent Germination ◽

Dry Heating

Echinacea is a medicinal plant native to North America. It was used extensively by native Americans in the treatment of their ailments. It is presently one of the most popular medicinal plants in the United States. Its popularity has created a large market demand for the roots and foliage of the plant. The gathering of echinacea from the wild is leading to the reduction of native populations and the destruction of its genetic diversity. Cultivation of medicinal echinaceas is hindered by a low seed germination. Dormancy breaking studies were done on freshly harvested seeds of Echinacea angustifolia. Seed lots were placed under light at a constant temperature of 25 °C and at alternate temperatures of 25/15 °C for 14/10 h, respectively. Germination was more rapid and uniform and percent germination higher at 25 °C than at 25/15 °C. Seed tap-water soaking, dry heating, and sharp heating alteration did not increase germination. The application of 1.0 mM ethephon (2-chloroethylphosphoric acid) increased seed germination to 94% at 25 °C and 86% at 25/15 °C. Untreated seeds gave 65% germination at 25 °C and 11% at 25/15 °C. The application of 2500 mg·L–1 and 3500 mg·L–1 of GA to dry seeds and 2500 mg·L–1 to seeds that have been soaked under tap water and then dried increased germination to 82%, 83%, and 83% at 25 °C and 64%, 78%, and 64% at 25/15 °C, respectively.

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