scholarly journals Bacteriophage Migration via Nematode Vectors: Host-Parasite-Consumer Interactions in Laboratory Microcosms

2006 ◽  
Vol 72 (3) ◽  
pp. 1974-1979 ◽  
Author(s):  
John J. Dennehy ◽  
Nicholas A. Friedenberg ◽  
Yul W. Yang ◽  
Paul E. Turner
Keyword(s):  
Experimental Studies ◽  
Virus Transmission ◽  
Growth Dynamics ◽  
Model System ◽  
Pathogen Transmission ◽  
Trophic Levels ◽  
Future Research ◽  
Evolution Of Virulence ◽  
Consumer Interactions ◽  
Host Parasite

ABSTRACT Pathogens vectored by nematodes pose serious agricultural, economic, and health threats; however, little is known of the ecological and evolutionary aspects of pathogen transmission by nematodes. Here we describe a novel model system with two trophic levels, bacteriophages and nematodes, each of which competes for bacteria. We demonstrate for the first time that nematodes are capable of transmitting phages between spatially distinct patches of bacteria. This model system has considerable advantages, including the ease of maintenance and manipulation at the laboratory bench, the ability to observe many generations in short periods, and the capacity to freeze evolved strains for later comparison to their ancestors. More generally, experimental studies of complex multispecies interactions, host-pathogen coevolution, disease dynamics, and the evolution of virulence may benefit from this model system because current models (e.g., chickens, mosquitoes, and malaria parasites) are costly to maintain, are difficult to manipulate, and require considerable space. Our initial explorations centered on independently assessing the impacts of nematode, bacterium, and phage population densities on virus migration between host patches. Our results indicated that virus transmission increases with worm density and host bacterial abundance; however, transmission decreases with initial phage abundance, perhaps because viruses eliminate available hosts before migration can occur. We discuss the microbial growth dynamics that underlie these results, suggest mechanistic explanations for nematode transmission of phages, and propose intriguing possibilities for future research.

Territorial consumer behaviors on social media: a dark side of psychological ownership

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Petru Dorin Micu ◽  
Christy Ashley
Keyword(s):  
Social Media ◽  
Experimental Studies ◽  
Psychological Ownership ◽  
Dark Side ◽  
Future Research ◽  
Consumer Behaviors ◽  
Content Type ◽  
Consumer Responses ◽  
Media Firms ◽  
Consumer Interactions

Purpose The purpose of this paper is to investigate whether consumers experience territory infringements during interactions with other consumers on firm-managed social media pages and, if so, how consumers respond. In offline contexts, feelings of territoriality affect consumers’ responses to other people in ways that are detrimental to the firm. Less is known about the effects of territoriality in response to consumer-to-consumer interactions on social media. Firms need to understand the implications of these interactions as they encourage consumer engagement on firm-owned social media pages. Design/methodology/approach The current research examines whether territorial consumer behaviors occur in response to co-consumers on social media pages for a brand (Study 1) and a product (Study 2) using experimental studies. Findings The studies provide evidence that a perceived territory infringement by a co-consumer can provoke retaliation toward the co-consumer and reduce engagement on the firm-owned social media page. Psychological ownership toward the product or brand amplifies these effects. Research limitations/implications The findings were robust in the experimental scenarios that featured a brand and a product. However, future research should validate the results in a field study and include other brands and products. Practical implications The findings highlight conditions under which consumer-to-consumer interactions can decrease social media engagement on firm-owned social media pages. Originality/value The manuscript is the first to examine how territoriality and psychological ownership relate to negative consumer responses following consumer-to-consumer interactions on social media.

RECLAMATION AND CULVERT CROSSINGS MADE OF CORRUGATED PIPES ON SPAWNING STREAMS

2020 ◽  
pp. 68-77
Author(s):  
O.N. CHERNYKH ◽  
◽  
A.V. RBURLACHENKO
Keyword(s):  
Single Point ◽  
Experimental Studies ◽  
Fish Passage ◽  
Future Research ◽  
Fish Stocks ◽  
Metal Structures ◽  
Natural Reproduction ◽  
Spiral Shape ◽  
Corrugated Metal ◽  
Spawning Streams

Recommendations are presented for solving issues that arise in the design and operation of tubular transport crossings of corrugated metal structures through spawning streams while ensuring the safety and natural reproduction of fish stocks. There are discussed the results of experimental studies of culverts made of metal corrugated pipes with a normal and spiral shape of corrugation the bottom of which is buried and filled with suitable granular material to the level of the natural channel of a small watercourse. It is established that when 10% of the area of the corrugated pipe is occupied by stone filling, its throughput is reduced by about 10-12%. Based on the review of the existing literature and the results of laboratory experiments, data is provided to estimate the values of the roughness coefficients of the composite cross-section of a single-point junction and directions for future research on culvert reclamation are outlined. Studying of the structure of the velocity distribution in culverts can lead to the improved conditions for fish passage without installing special structural elements in the transit path of the fish passage structure.

Microbiological substantiation of application of phytopreparations in treatment of inflammatory periodontal diseases

2019 ◽  
Vol 24 (3) ◽  
pp. 196-202 ◽  
Author(s):  
S. A. Abdurakhmanova ◽  
G. S. Runova ◽  
M. S. Podporin ◽  
E. V. Tsareva ◽  
E. V. Ippolitov ◽  
...  
Keyword(s):  
Tooth Loss ◽  
Periodontal Diseases ◽  
Adult Population ◽  
Experimental Studies ◽  
Herbal Medicines ◽  
Growth Dynamics ◽  
Integrated Approach ◽  
Bacterial Populations ◽  
Streptococcus Constellatus ◽  
Urgent Task

Relevance: Inflammatory-destructive periodontal diseases are the most complicated and became the main cause of tooth loss in adult population. Herbal medicines have a variety of pharmacological properties, so the development and introduction of new forms for the treatment of inflammatory periodontal diseases is an urgent task today.Purpose – experimental evaluation of effectiveness of the use of herbal medicines “Tonzinal” and “CM-1” in relation to the priority periodontal pathogenes.Materials and methods: in experimental studies, the basis for the experiment was the system for the cultivation of microorganisms in real time – the Revers-Spinner RTS-1 bioreactor. With the priority strains of periodontitis pathogens, the study of the growth dynamics of the culture was carried out in several parallels.Results: herbal medicines “CM-1” and “Tonsinal” has a multilateral therapeutic effect, exerting a diverse influence on the key stages of development of such bacterial populations as Aggregatibacter actinomycetemcomitans, Streptococcus constellatus, Candida albicans.Conclusion: tan integrated approach in the treatment of patients with inflammatory periodontal diseases is promising and will contribute to a more prolonged remission and increase the effectiveness of treatment. 

Amruthapala (Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter): A Comprehensive Review on Diversity, Therapeutic Uses, and Valorization of Bioactive Constituents

2019 ◽  
Vol 20 (5) ◽  
pp. 376-389 ◽  
Author(s):  
Sonali Mishra ◽  
Nupur Srivastava ◽  
Velusamy Sundaresan ◽  
Karuna Shanker
Keyword(s):  
Secondary Metabolite ◽  
Current Knowledge ◽  
Experimental Studies ◽  
Critical Discussion ◽  
Future Research ◽  
Bioactive Constituents ◽  
Medicinal Uses ◽  
Comprehensive Review ◽  
Therapeutic Uses ◽  
Decalepis Arayalpathra

Background: Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter is used primarily for nutrition besides its therapeutic values. Traditional preparations/formulations from its tuber are used as a vitalizer and blood purifier drink. The folklore medicinal uses cover inflammation, cough, wound healing, antipyretic, and digestive system management. A comprehensive review of the current understanding of the plant is required due to emerging concerns over its safety and efficacy. Objective: The systematic collection of the authentic information from different sources with the critical discussion is summarised in order to address various issues related to botanical identity, therapeutic medicine, nutritional usage, phytochemical, and pharmacological potentials of the D. arayalpathra. Current use of traditional systems of medicine can be used to expand future research opportunities. Materials and Methods: Available scripted information was collected manually, from peered review research papers and international databases viz. Science Direct, Google Scholar, SciFinder, Scopus, etc. The unpublished resources which were not available in database were collected through the classical books of ‘Ayurveda’ and ‘Siddha’ published in regional languages. The information from books, Ph.D. and MSc dissertations, conference papers and government reports were also collected. We thoroughly screened the scripted information of classical books, titles, abstracts, reports, and full-texts of the journals to establish the reliability of the content. Results: Tuber bearing vanilla like signature flavor is due to the presence of 2-hydroxy-4-methoxybenzaldehyde (HMB). Among five other species, Decalepis arayalpathra (DA) has come under the ‘critically endangered’ category, due to over-exploitation for traditional, therapeutic and cool drink use. The experimental studies proved that it possesses gastro-protective, anti-tumor, and antiinflammatory activities. Some efforts were also made to develop better therapeutics by logical modifications in 2-Hydroxy-4-methoxy-benzaldehyde, which is a major secondary metabolite of D. arayalpathra. ‘Amruthapala’ offers the enormous opportunity to develop herbal drink with health benefits like gastro-protective, anti-oxidant and anti-inflammatory actions. Results: The plant has the potential to generate the investigational new lead (IND) based on its major secondary metabolite i.e. 2-Hydroxy-4-methoxy-benzaldehyde. The present mini-review summarizes the current knowledge on Decalepis arayalpathra, covering its phytochemical diversity, biological potentials, strategies for its conservation, and intellectual property rights (IPR) status. Chemical Compounds: 2-hydroxy-4-methoxybenzaldehyde (Pubchem CID: 69600), α-amyrin acetate (Pubchem CID: 293754), Magnificol (Pubchem CID: 44575983), β-sitosterol (Pubchem CID: 222284), 3-hydroxy-p-anisaldehyde (Pubchem CID: 12127), Naringenin (Pubchem CID: 932), Kaempferol (Pubchem CID: 5280863), Aromadendrin (Pubchem CID: 122850), 3-methoxy-1,2-cyclopentanedione (Pubchem CID: 61209), p-anisaldehyde (Pubchem CID: 31244), Menthyl acetate (Pubchem CID: 27867), Benzaldehyde (Pubchem CID: 240), p-cymene (Pubchem CID: 7463), Salicylaldehyde (Pubchem CID: 6998), 10-epi-γ-eudesmol (Pubchem CID: 6430754), α -amyrin (Pubchem CID: 225688), 3-hydroxy-4-methoxy benzaldehyde (Pubchem CID: 12127).

scholarly journals 491. Aerosol-Generating Medical Procedures: Transmission of SARS-CoV-2 and Emerging Viruses

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S312-S312
Author(s):  
Seth D Judson ◽  
Vincent J Munster
Keyword(s):  
High Risk ◽  
Severe Disease ◽  
Experimental Studies ◽  
Virus Transmission ◽  
Nosocomial Transmission ◽  
Medical Procedures ◽  
Emerging Viruses ◽  
Zoonotic Viruses ◽  
Increased Risk ◽  
Hospital Acquired

Abstract Background During the pandemic of coronavirus disease 2019 (COVID-19), many questions arose regarding risks for hospital-acquired or nosocomial transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Aerosol generating medical procedures (AGMPs), techniques that can generate infectious, virus-laden aerosols, could potentially amplify transmission among healthcare workers (HCWs). Thus, it was widely recommended that HCWs use airborne precautions when performing AGMPs. However, in clinical settings it is often unclear what procedures constitute AGMPs and how the risk varies by procedure or pathogen. We set out to further define AGMPs and assess the risk for nosocomial transmission of SARS-CoV-2 and other high-risk viruses via AGMPs. Methods We identified potential AGMPs and emerging viruses that were high-risk for nosocomial transmission through reviewing experimental and clinical data. Potential AGMPs were those associated with previous virus transmission or mechanically capable of transmission. High-risk viruses were defined as those that cause severe disease in humans for which limited therapies or interventions exist, are infectious via aerosols in humans or non-human primates (NHPs), found in the respiratory tract of infected humans or NHPs, and had previous evidence of nosocomial transmission. Results We identified multiple potential AGMPs, which could be divided into those that generate aerosols or induce a patient to form aerosols, as well as eight families of high-risk viruses. All of the viruses were emerging zoonotic RNA viruses. In the family Coronaviridae, we identified potential evidence for SARS-CoV-1, MERS-CoV, and SARS-CoV-2 transmission via AGMPs. SARS-CoV-1 and SARS-CoV-2 were also found to be similarly stable when aerosolized. Conclusion Multiple emerging zoonotic viruses pose a high risk for nosocomial transmission through a variety of AGMPs. Given the similar stability of SARS-CoV-2 with SARS-CoV-1 when aerosolized and prior nosocomial transmission of SARS-CoV-1 via AGMPs, we suspect that certain AGMPs pose an increased risk for SARS-CoV-2 transmission. Additional experimental studies and on-site clinical sampling during AGMPs are necessary to further risk stratify AGMPs. Disclosures All Authors: No reported disclosures

scholarly journals Local Anesthetics and Recurrence after Cancer Surgery-What’s New? A Narrative Review

2021 ◽  
Vol 10 (4) ◽  
pp. 719
Author(s):  
Sarah D. Müller ◽  
Jonathan S. H. Ziegler ◽  
Tobias Piegeler
Keyword(s):  
Tumor Cells ◽  
Circulating Tumor Cells ◽  
Local Anesthetics ◽  
Experimental Studies ◽  
Perioperative Period ◽  
Cancer Surgery ◽  
Narrative Review ◽  
Future Research ◽  
Inflammatory Stress ◽  
Research Activities

The perioperative use of regional anesthesia and local anesthetics is part of almost every anesthesiologist’s daily clinical practice. Retrospective analyses and results from experimental studies pointed towards a potential beneficial effect of the local anesthetics regarding outcome—i.e., overall and/or recurrence-free survival—in patients undergoing cancer surgery. The perioperative period, where the anesthesiologist is responsible for the patients, might be crucial for the further course of the disease, as circulating tumor cells (shed from the primary tumor into the patient’s bloodstream) might form new micro-metastases independent of complete tumor removal. Due to their strong anti-inflammatory properties, local anesthetics might have a certain impact on these circulating tumor cells, either via direct or indirect measures, for example via blunting the inflammatory stress response as induced by the surgical stimulus. This narrative review highlights the foundation of these principles, features recent experimental and clinical data and provides an outlook regarding current and potential future research activities.

Contracture Severity at Hospital Discharge in Children: A Burn Model System Database Study

2020 ◽  
Author(s):  
Miranda Yelvington ◽  
Matthew Godleski ◽  
Austin F Lee ◽  
Jeremy Goverman ◽  
Ingrid Parry ◽  
...  
Keyword(s):  
Length Of Stay ◽  
Range Of Motion ◽  
Hospital Discharge ◽  
Injury Severity ◽  
Model System ◽  
Future Research ◽  
P Value ◽  
Local Practices ◽  
Improvement Measures ◽  
Joint Motions

Abstract Contractures can complicate burn recovery. There are limited studies examining the prevalence of contractures following burns in pediatrics. This study investigates contracture outcomes by location, injury, severity, length of stay, and developmental stage. Data were obtained from the Burn Model System between 1994 and 2003. All patients younger than the age of 18 with at least one joint contracture at hospital discharge were included. Sixteen areas of impaired movement from the shoulder, elbow, wrist, hand, hip, knee, and ankle joints were examined. Analysis of variance was used to assess the association between contracture severity, burn size, and length of stay. Age groupings were evaluated for developmental patterns. A P value of less than .05 was considered statistically significant. Data from 225 patients yielded 1597 contractures (758 in the hand) with a mean of 7.1 contractures (median 4) per patient. Mean contracture severity ranged from 17% (elbow extension) to 41% (ankle plantarflexion) loss of movement. Statistically significant associations were found between active range of motion loss and burn size, length of stay, and age groupings. The data illustrate quantitative assessment of burn contractures in pediatric patients at discharge in a multicenter database. Size of injury correlates with range of motion loss for many joint motions, reflecting the anticipated morbidity of contracture for pediatric burn survivors. These results serve as a potential reference for range of motion outcomes in the pediatric burn population, which could serve as a comparison for local practices, quality improvement measures, and future research.

scholarly journals A roadmap: Social distancing physical activity data collection to protect those with intellectual disabilities

2021 ◽  
pp. 174462952110096
Author(s):  
Whitley J Stone ◽  
Kayla M Baker
Keyword(s):  
Physical Activity ◽  
Data Collection ◽  
Intellectual Disabilities ◽  
Research Methods ◽  
Virus Transmission ◽  
Future Research ◽  
Activity Data ◽  
Physical Activity Data ◽  
Social Distancing ◽  
Novel Coronavirus

The novel coronavirus may impact exercise habits of those with intellectual disabilities. Due to the mandated discontinuation of face-to-face research, investigators must adapt projects to protect all involved while collecting objective physical activity metrics. This brief report outlines a modification process of research methods to adhere to social distancing mandates present during COVID-19. Actions taken included electronic consent and assent forms, an electronic survey, and mailing an accelerometer with included instructions. The amended research methods were implemented without risk for virus transmission or undue burden on the research team, participant, or caregiver. Recruitment was likely impacted by the coronavirus-mediated quarantine, plausibly resulting in bias. Objective physical activity data collection can be sufficiently modified to protect those with intellectual disabilities and investigators. Future research designs may require greater participant incentives and the creation of in-home participation.

scholarly journals Opportunistic Large Array Propagation Models: A Comprehensive Survey

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4206
Author(s):  
Farhan Nawaz ◽  
Hemant Kumar ◽  
Syed Ali Hassan ◽  
Haejoon Jung
Keyword(s):  
Energy Efficient ◽  
Large Scale ◽  
Performance Metrics ◽  
Experimental Studies ◽  
Cooperative Transmission ◽  
Analytical Models ◽  
Future Research ◽  
Large Array ◽  
Propagation Models ◽  
Comprehensive Survey

Enabled by the fifth-generation (5G) and beyond 5G communications, large-scale deployments of Internet-of-Things (IoT) networks are expected in various application fields to handle massive machine-type communication (mMTC) services. Device-to-device (D2D) communications can be an effective solution in massive IoT networks to overcome the inherent hardware limitations of small devices. In such D2D scenarios, given that a receiver can benefit from the signal-to-noise-ratio (SNR) advantage through diversity and array gains, cooperative transmission (CT) can be employed, so that multiple IoT nodes can create a virtual antenna array. In particular, Opportunistic Large Array (OLA), which is one type of CT technique, is known to provide fast, energy-efficient, and reliable broadcasting and unicasting without prior coordination, which can be exploited in future mMTC applications. However, OLA-based protocol design and operation are subject to network models to characterize the propagation behavior and evaluate the performance. Further, it has been shown through some experimental studies that the most widely-used model in prior studies on OLA is not accurate for networks with networks with low node density. Therefore, stochastic models using quasi-stationary Markov chain are introduced, which are more complex but more exact to estimate the key performance metrics of the OLA transmissions in practice. Considering the fact that such propagation models should be selected carefully depending on system parameters such as network topology and channel environments, we provide a comprehensive survey on the analytical models and framework of the OLA propagation in the literature, which is not available in the existing survey papers on OLA protocols. In addition, we introduce energy-efficient OLA techniques, which are of paramount importance in energy-limited IoT networks. Furthermore, we discuss future research directions to combine OLA with emerging technologies.

scholarly journals Does the model of additive effect in placebo research still hold true? A narrative review

JRSM Open ◽  
2017 ◽  
Vol 8 (3) ◽  
pp. 205427041668143 ◽  
Author(s):  
Katja Boehm ◽  
Bettina Berger ◽  
Ulrich Weger ◽  
Peter Heusser
Keyword(s):  
Context Effects ◽  
Experimental Studies ◽  
Additive Model ◽  
Drug Effects ◽  
Future Research ◽  
Inclusion Criteria ◽  
Integrative Study ◽  
Additive Relation ◽  
Specific Factors ◽  
Study Designs

Personalised and contextualised care has been turned into a major demand by people involved in healthcare suggesting to move toward person-centred medicine. The assessment of person-centred medicine can be most effectively achieved if treatments are investigated using ‘with versus without’ person-centredness or integrative study designs. However, this assumes that the components of an integrative or person-centred intervention have an additive relationship to produce the total effect. Beecher’s model of additivity assumes an additive relation between placebo and drug effects and is thus presenting an arithmetic summation. So far, no review has been carried out assessing the validity of the additive model, which is to be questioned and more closely investigated in this review. Initial searches for primary studies were undertaken in July 2016 using Pubmed and Google Scholar. In order to find matching publications of similar magnitude for the comparison part of this review, corresponding matches for all included reviews were sought. A total of 22 reviews and 3 clinical and experimental studies fulfilled the inclusion criteria. The results pointed to the following factors actively questioning the additive model: interactions of various effects, trial design, conditioning, context effects and factors, neurobiological factors, mechanism of action, statistical factors, intervention-specific factors (alcohol, caffeine), side-effects and type of intervention. All but one of the closely assessed publications was questioning the additive model. A closer examination of study design is necessary. An attempt in a more systematic approach geared towards solutions could be a suggestion for future research in this field.

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