qPCR Assays for the Detection of Cylindrocladium buxicola in Plant, Water, and Air Samples

Cylindrocladium buxicola (syn. C. pseudonaviculatum; teleomorph Calonectria pseudonaviculata) is an important fungal pathogen of Buxus spp. Although widespread in Western Europe, this pathogen has only recently been introduced into North America, where it represents a significant threat to the U.S. and Canadian boxwood industries. Trade of latently infected nursery stock is an important mode of long-distance dissemination and introduction of this pathogen but no methods for detection of latently infected material are available. Also, the pathways for short-distance dispersal of C. buxicola have not been adequately studied. Improved detection methods of this pathogen in air and water samples would benefit future research in this area. We have developed real-time polymerase chain reaction assays for the detection of C. buxicola based on the ribosomal DNA internal transcribed spacer 1 (ITS) and the β-tubulin 2 gene (TUB). Using a TaqMan probe conjugated with a 3′ minor groove binding group (TaqMan MGB probe), the ITS-based assay could reliably detect as little as 10 fg of genomic DNA or 20 copies of cloned target DNA and was approximately 70 times more sensitive than the SYBR Green TUB-based assay. The ITS-based assay provided good but not complete specificity, and is well suited for epidemiological studies. The TUB-based assay, however, proved to be fully specific and can be used for diagnostics. We developed and optimized sample processing and DNA extraction methods for detection of latently present C. buxicola in boxwood plants and quantification of conidia in water and air samples. C. buxicola could be detected in 20 g of plant material, of which only 1 ppm of the tissue was infected, in 10-ml water samples containing as low as 1 conidium/ml, and on Melinex tape pieces representing 12 h of air sampling containing 10 or more conidia. The applicability of the techniques to plant, water, and air samples of practical size was demonstrated.

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Citrus Essential Oils (CEOs) and Their Applications in Food: An Overview

Plants ◽

10.3390/plants9030357 ◽

2020 ◽

Vol 9 (3) ◽

pp. 357 ◽

Cited By ~ 7

Author(s):

Himashree Bora ◽

Madhu Kamle ◽

Dipendra Kumar Mahato ◽

Pragya Tiwari ◽

Pradeep Kumar

Keyword(s):

Essential Oils ◽

Antimicrobial Properties ◽

Cost Effective ◽

Extraction Methods ◽

Biologically Active ◽

Detection Methods ◽

Future Research ◽

Optimum Dose ◽

Food Applications ◽

Citrus Essential Oils

Citrus is a genus belonging to the Rutaceae family and includes important crops like orange, lemons, pummelos, grapefruits, limes, etc. Citrus essential oils (CEOs) consist of some major biologically active compounds like α-/β-pinene, sabinene, β-myrcene, d-limonene, linalool, α-humulene, and α-terpineol belonging to the monoterpenes, monoterpene aldehyde/alcohol, and sesquiterpenes group, respectively. These compounds possess several health beneficial properties like antioxidant, anti-inflammatory, anticancer, etc., in addition to antimicrobial properties, which have immense potential for food applications. Therefore, this review focused on the extraction, purification, and detection methods of CEOs along with their applications for food safety, packaging, and preservation. Further, the concerns of optimum dose and safe limits, their interaction effects with various food matrices and packaging materials, and possible allergic reactions associated with the use of CEOs in food applications were briefly discussed, which needs to be addressed in future research along with efficient, affordable, and “green” extraction methods to ensure CEOs as an ecofriendly, cost-effective, and natural alternative to synthetic chemical preservatives.

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Validation and application of a cryogenic vacuum extraction system for soil and plant water extraction for isotope analysis

Journal of Sensors and Sensor Systems ◽

10.5194/jsss-2-179-2013 ◽

2013 ◽

Vol 2 (2) ◽

pp. 179-193 ◽

Cited By ~ 78

Author(s):

N. Orlowski ◽

H.-G. Frede ◽

N. Brüggemann ◽

L. Breuer

Keyword(s):

Isotopic Composition ◽

Water Samples ◽

Isotope Analysis ◽

Isotopic Analysis ◽

Extraction Methods ◽

Extraction System ◽

Vacuum System ◽

Vacuum Extraction ◽

Plant Water ◽

Cryogenic Vacuum

Abstract. Stable isotopic analysis of water in plant, soil, and hydrological studies often requires the extraction of water from plant or soil samples. Cryogenic vacuum extraction is one of the most widely used and accurate extraction methods to obtain such water samples. Here, we present a new design of a cryogenic vacuum extraction system with 18 extraction slots and an innovative mechanism to aerate the vacuum system after extraction. This mobile and extendable multi-port extraction system overcomes the bottleneck of time required for capturing unfractionated extracted water samples by providing the possibility to extract a larger number of samples per day simultaneously. The aeration system prevents the loss or mixture of water vapor during defrosting by purging every sample with high-purity nitrogen gas. A set of system functionality tests revealed that the extraction device guarantees stable extraction conditions with no changes in the isotopic composition of the extracted water samples. Surprisingly, extractions of dried and rehydrated soils showed significant differences of the isotopic composition of the added water and the extracts. This observation challenges the assumption that cryogenic extraction systems to fully extract soil water. Furthermore, in a plant water uptake study different results for hydrogen and oxygen isotope data were obtained, raising problems in the definition from which depths plants really take up water. Results query whether the well-established and widely used cryogenic vacuum distillation method can be used in a standard unified method of fixed extraction times as it is often done.

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Going the Distance

10.23943/princeton/9780691150772.001.0001 ◽

2020 ◽

Author(s):

Ron Harris

Keyword(s):

Large Scale ◽

Western Europe ◽

Family Firms ◽

Global Trade ◽

Long Distance ◽

Business Corporation ◽

Modern Economy ◽

Key Factor ◽

Silk Route ◽

Passive Investors

Before the seventeenth century, trade across Eurasia was mostly conducted in short segments along the Silk Route and Indian Ocean. Business was organized in family firms, merchant networks, and state-owned enterprises, and dominated by Chinese, Indian, and Arabic traders. However, around 1600 the first two joint-stock corporations, the English and Dutch East India Companies, were established. This book tells the story of overland and maritime trade without Europeans, of European Cape Route trade without corporations, and of how new, large-scale, and impersonal organizations arose in Europe to control long-distance trade for more than three centuries. It shows that by 1700, the scene and methods for global trade had dramatically changed: Dutch and English merchants shepherded goods directly from China and India to northwestern Europe. To understand this transformation, the book compares the organizational forms used in four major regions: China, India, the Middle East, and Western Europe. The English and Dutch were the last to leap into Eurasian trade, and they innovated in order to compete. They raised capital from passive investors through impersonal stock markets and their joint-stock corporations deployed more capital, ships, and agents to deliver goods from their origins to consumers. The book explores the history behind a cornerstone of the modern economy, and how this organizational revolution contributed to the formation of global trade and the creation of the business corporation as a key factor in Europe's economic rise.

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A Survey on Deep Learning Based Methods and Datasets for Monocular 3D Object Detection

Electronics ◽

10.3390/electronics10040517 ◽

2021 ◽

Vol 10 (4) ◽

pp. 517

Author(s):

Seong-heum Kim ◽

Youngbae Hwang

Keyword(s):

Deep Learning ◽

Object Detection ◽

Low Cost ◽

Detection Methods ◽

Future Research ◽

3D Object ◽

Practical Applications ◽

Depth Sensors ◽

Significant Research ◽

3D Object Detection

Owing to recent advancements in deep learning methods and relevant databases, it is becoming increasingly easier to recognize 3D objects using only RGB images from single viewpoints. This study investigates the major breakthroughs and current progress in deep learning-based monocular 3D object detection. For relatively low-cost data acquisition systems without depth sensors or cameras at multiple viewpoints, we first consider existing databases with 2D RGB photos and their relevant attributes. Based on this simple sensor modality for practical applications, deep learning-based monocular 3D object detection methods that overcome significant research challenges are categorized and summarized. We present the key concepts and detailed descriptions of representative single-stage and multiple-stage detection solutions. In addition, we discuss the effectiveness of the detection models on their baseline benchmarks. Finally, we explore several directions for future research on monocular 3D object detection.

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Preliminary Examination of the Toxicity of Spalting Fungal Pigments: A Comparison between Extraction Methods

Journal of Fungi ◽

10.3390/jof7020155 ◽

2021 ◽

Vol 7 (2) ◽

pp. 155

Author(s):

Badria H. Almurshidi ◽

R.C. Van Court ◽

Sarath M. Vega Gutierrez ◽

Stacey Harper ◽

Bryan Harper ◽

...

Keyword(s):

Extraction Methods ◽

Green Energy ◽

Future Research ◽

Green Technologies ◽

Preliminary Examination ◽

Significant Toxicity ◽

Natural Colorants ◽

Industrial Adoption ◽

Synthetic Colorants ◽

Fungal Pigments

Spalting fungal pigments have shown potential in technologies ranging from green energy generation to natural colorants. However, their unknown toxicity has been a barrier to industrial adoption. In order to gain an understanding of the safety of the pigments, zebrafish embryos were exposed to multiple forms of liquid media and solvent-extracted pigments with concentrations of purified pigment ranging from 0 to 50 mM from Chlorociboria aeruginosa, Chlorociboria aeruginascens, and Scytalidium cuboideum. Purified xylindein from Chlorociboria sp. did not show toxicity at any tested concentration, while the red pigment dramada from S. cuboideum was only associated with significant toxicity above 23.2 uM. However, liquid cultures and pigment extracted into dichloromethane (DCM) showed toxicity, suggesting the co-production of bioactive secondary metabolites. Future research on purification and the bioavailability of the red dramada pigment will be important to identify appropriate use; however, purified forms of the blue-green pigment xylindein are likely safe for use across industries. This opens the door to the adoption of green technologies based on these pigments, with potential to replace synthetic colorants and less stable natural pigments.

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Review of Electrochemical DNA Biosensors for Detecting Food Borne Pathogens

Sensors ◽

10.3390/s19224916 ◽

2019 ◽

Vol 19 (22) ◽

pp. 4916 ◽

Cited By ~ 4

Author(s):

Qiaoyun Wu ◽

Yunzhe Zhang ◽

Qian Yang ◽

Ning Yuan ◽

Wei Zhang

Keyword(s):

Pathogen Detection ◽

Low Cost ◽

Electrochemical Techniques ◽

Ease Of Use ◽

Detection Methods ◽

Future Research ◽

Dna Biosensors ◽

Food Borne Pathogens ◽

Chip Technology ◽

Food Borne

The vital importance of rapid and accurate detection of food borne pathogens has driven the development of biosensor to prevent food borne illness outbreaks. Electrochemical DNA biosensors offer such merits as rapid response, high sensitivity, low cost, and ease of use. This review covers the following three aspects: food borne pathogens and conventional detection methods, the design and fabrication of electrochemical DNA biosensors and several techniques for improving sensitivity of biosensors. We highlight the main bioreceptors and immobilizing methods on sensing interface, electrochemical techniques, electrochemical indicators, nanotechnology, and nucleic acid-based amplification. Finally, in view of the existing shortcomings of electrochemical DNA biosensors in the field of food borne pathogen detection, we also predict and prospect future research focuses from the following five aspects: specific bioreceptors (improving specificity), nanomaterials (enhancing sensitivity), microfluidic chip technology (realizing automate operation), paper-based biosensors (reducing detection cost), and smartphones or other mobile devices (simplifying signal reading devices).

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Weak Transient Electromagnetic Radiation Signal Detection Method Considering the New Watershed Image Segmentation Algorithm

International Journal of Pattern Recognition and Artificial Intelligence ◽

10.1142/s0218001420540099 ◽

2019 ◽

Vol 34 (03) ◽

pp. 2054009

Author(s):

Wenjun Huo ◽

Peng Chu ◽

Kai Wang ◽

Liangting Fu ◽

Zhigang Niu ◽

...

Keyword(s):

Electromagnetic Radiation ◽

Cross Correlation ◽

Detection Efficiency ◽

Signal To Noise Ratio ◽

Estimation Method ◽

Detection Methods ◽

Signal To Noise ◽

Long Distance ◽

Transient Electromagnetic ◽

Noise Ratio

In order to study the detection methods of weak transient electromagnetic radiation signals, a detection algorithm integrating generalized cross-correlation and chaotic sequence prediction is proposed in this paper. Based on the dual-antenna test and cross-correlation information estimation method, the detection of aperiodic weak discharge signals under low signal-to-noise ratio is transformed into the estimation of periodic delay parameters, and the noise is reduced at the same time. The feasibility of this method is verified by simulation and experimental analysis. The results show that under the condition of low signal-to-noise ratio, the integrated method can effectively suppress the influence of 10 noise disturbances. It has a high detection probability for weak transient electromagnetic radiation signals, and needs fewer pulse accumulation times, which improves the detection efficiency and is more suitable for long-distance detection of weak electromagnetic radiation sources.

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Risk assessment of waterborne protozoa: current status and future trends

Parasitology ◽

10.1017/s0031182099004746 ◽

1999 ◽

Vol 117 (7) ◽

pp. 205-212 ◽

Cited By ~ 21

Author(s):

C. J. GIBSON ◽

C. N. HAAS ◽

J. B. ROSE

Keyword(s):

Risk Assessment ◽

Management Practices ◽

Assessment Methods ◽

Detection Methods ◽

Current Status ◽

Future Research ◽

Microbial Risk Assessment ◽

Microbial Risk ◽

Chemical Risk Assessment ◽

Low Levels

Throughout the past decade much research has been directed towards identifying the occurrence, epidemiology, and risks associated with waterborne protozoa. While outbreaks are continually documented, sporadic cases of disease associated with exposure to low levels of waterborne protozoa are of increasing concern. Current methodologies may not be sensitive enough to define these low levels of disease. However, risk assessment methods may be utilised to address these low level contamination events. The purpose of this article is to provide an introduction to microbial risk assessment for waterborne protozoa. Risk assessment is a useful tool for evaluating relative risks and can be used for development of policies to decrease risks. Numerous studies have been published on risk assessment methods for pathogenic protozoa including Cryptosporidium and Giardia. One common notion prevails: microbial risk assessment presents interesting complications to the traditional chemical risk assessment paradigm. Single microbial exposures (non-threshold) are capable of causing symptomatic illness unlike traditional chemical exposures, which require a threshold to be reached. Due to the lack of efficient recovery and detection methods for protozoa, we may be underestimating the occurrence, concentration and distribution of these pathogenic micro-organisms. To better utilize the tool of microbial risk assessment for risk management practices, future research should focus in the area of exposure assessment.

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Archaic Origins of the Lowland Maya

Latin American Antiquity ◽

10.7183/1045-6635.21.3.312 ◽

2010 ◽

Vol 21 (3) ◽

pp. 312-352 ◽

Cited By ~ 38

Author(s):

Jon C. Lohse

Keyword(s):

Cultural Change ◽

New Technologies ◽

Cultural Practices ◽

Future Research ◽

Late Archaic ◽

Long Distance ◽

Radiocarbon Data ◽

Cultural Origins ◽

Lines Of Evidence ◽

Lowland Maya

The earliest Lowland Maya are commonly recognized by permanent architecture and the appearance of pottery. However, when other lines of evidence are considered, strong continuities with late Archaic populations can be seen. Reconciling these views relies on more than simply gathering more data. It is also necessary to consider the effect of decades of scholarship that defines the precolumbian Maya as “civilization” rather than considering the historical contexts of important transitions, such as the one that culminated with sedentism, the adoption of new technologies, and participation in long-distance exchange. The Archaic-to-Preclassic transition was relatively brief and largely obscured by the practices of establishing permanent dwellings. Nevertheless, this period must have been extremely dynamic and marked by significant cultural change, making it important to researchers interested in early Mesoamerica. Using three lines of evidence—subsistence, economy and technology, and stratigraphically controlled radiocarbon data—this article argues that the Lowland Maya had their cultural origins at least in the late Archaic and that the case for pottery before ca. 1000 B.C. remains uncertain. Future research is needed to determine precisely how far back in time certain cultural practices that characterize Preclassic and Classic Maya society can be documented.

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The movement ecology of seagrasses

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.0878 ◽

2014 ◽

Vol 281 (1795) ◽

pp. 20140878 ◽

Cited By ~ 81

Author(s):

Kathryn McMahon ◽

Kor-jent van Dijk ◽

Leonardo Ruiz-Montoya ◽

Gary A. Kendrick ◽

Siegfried L. Krauss ◽

...

Keyword(s):

Life History ◽

Clonal Growth ◽

Movement Ecology ◽

Future Research ◽

The Novel ◽

Long Distance ◽

Spatial And Temporal Scales ◽

Life History Stages ◽

Research Areas ◽

Time Movement

A movement ecology framework is applied to enhance our understanding of the causes, mechanisms and consequences of movement in seagrasses: marine, clonal, flowering plants. Four life-history stages of seagrasses can move: pollen, sexual propagules, vegetative fragments and the spread of individuals through clonal growth. Movement occurs on the water surface, in the water column, on or in the sediment, via animal vectors and through spreading clones. A capacity for long-distance dispersal and demographic connectivity over multiple timeframes is the novel feature of the movement ecology of seagrasses with significant evolutionary and ecological consequences. The space–time movement footprint of different life-history stages varies. For example, the distance moved by reproductive propagules and vegetative expansion via clonal growth is similar, but the timescales range exponentially, from hours to months or centuries to millennia, respectively. Consequently, environmental factors and key traits that interact to influence movement also operate on vastly different spatial and temporal scales. Six key future research areas have been identified.

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