scholarly journals Microbial plankton community structure and function responses to vitamin B12 and B1 amendments in an upwelling system

2021 ◽  
Author(s):  
Vanessa Joglar ◽  
Benjamin Pontiller ◽  
Sandra Martínez ◽  
Antonio Fuentes-Lema ◽  
María Pérez-Lorenzo ◽  
...  
Keyword(s):  
Community Composition ◽  
B Vitamins ◽  
Nw Spain ◽  
Marine Systems ◽  
Vitamin Uptake ◽  
Living Organisms ◽  
B Vitamin ◽  
The Impact ◽  
Selection Of Microorganisms ◽  
Selection Of

B vitamins are essential cofactors for practically all living organisms on Earth that are produced by a selection of microorganisms. An imbalance between high demand and limited production, in concert with abiotic processes, may explain the low availability of these vitamins in marine systems. Natural microbial communities from surface shelf water in the productive area off NW Spain were enclosed in mesocosms in winter, spring and summer 2016. In order to explore the impact of B-vitamin availability on microbial community composition (16S and 18S rRNA gene sequence analysis) and bacterial function (metatranscriptomics analysis) in different seasons, enrichment experiments were conducted with seawater from the mesocosms. Our findings revealed that significant increases in phytoplankton or prokaryote biomass associated with B12 and/or B1 amendments were not accompanied by significant changes in community composition, suggesting that most of the microbial taxa benefited from the external B-vitamin supply. Metatranscriptome analysis suggested that many bacteria were potential consumers of B12 and B1 vitamins, although the relative abundance of reads related to synthesis was ca. 3.6-fold higher than that related to uptake. Alteromonadales and Oceanospirillales accounted for important portions of B1 and B12 vitamin synthesis gene transcription, despite accounting for only minor portions of the bacterial community. Flavobacteriales appeared to be mostly involved in B12 and B1 vitamin uptake and Pelagibacterales expressed genes involved in B1 vitamin uptake. Interestingly, the relative expression of B12 and B1 vitamin synthesis genes among bacteria strongly increased upon inorganic nutrient amendments. Collectively, these findings suggest that upwelling events intermittently occurring during spring and summer in productive ecosystems may ensure an adequate production of these cofactors to sustain high levels of phytoplankton growth and biomass. Importance Section B-vitamins are essential growth factors for practically all living organisms on Earth that are produced by a selection of microorganisms. An imbalance between high-demand and limited-production may explain the low concentration of these compounds in marine systems. In order to explore the impact of B-vitamin availability on bacteria and algae in the coastal waters off NW Spain, six experiments were conducted with natural surface water enclosed in winter, spring and summer. Our findings revealed that increases in phytoplankton or bacteria growth associated with B12 and/or B1 amendments were not accompanied by significant changes in community composition, suggesting that most microorganisms benefited from the B-vitamin supply. Our analyses confirmed the role of many bacteria as consumers of B12 and B1 vitamins, although the relative abundance of genes related to synthesis was ca. 3.6-fold higher than that related to uptake.Interestingly, prokaryote expression of B12 and B1-synthesis genes strongly increased when inorganic nutrient were added. Collectively, these findings suggest that upwelling of cold and nutrient-rich waters occurring during spring and summer in this cooastal area may ensure an adequate production of B vitamins to sustain high levels of algae growth and biomass.

scholarly journals B Vitamins and Cognitive Performance in Older Adults: Review

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
J. L. Reay ◽  
M. A. Smith ◽  
L. M. Riby
Keyword(s):  
Cognitive Function ◽  
Carbon Metabolism ◽  
Optimal Dose ◽  
Epidemiological Studies ◽  
B Vitamins ◽  
Therapeutic Window ◽  
Vitamin Therapy ◽  
One Carbon Metabolism ◽  
B Vitamin ◽  
The Impact

A copious amount of scientific scrutiny has been dedicated to documenting typical and atypical human ageing, with a substantial body of work focusing upon the impact of lifestyle choices. One such lifestyle choice is that of diet and, in particular, micronutrient ingestion. Epidemiological studies have reported positive associations between B vitamin status and cognitive function, including negative associations between biological markers (i.e., homocysteine) of dysregulated one-carbon metabolism and cognitive function. This has led to a surge of randomised control trials (RCTs) investigations into B vitamin therapy. However, results have continuingly failed to show beneficial behavioural effects. Despite this, results reliably show treatment-related increases in B vitamin level and decreases in homocysteine level—both of which have been identified as risk factors for atypical ageing. In this paper we argue that it would be premature to conclude that B vitamin therapy has no potential and that more research is needed to systematically investigate the optimal dose, the therapeutic “window,” and individual differences in therapy responders and nonresponders. We start with a brief look at one-carbon metabolism and then consider the evidence from epidemiological studies and RCTs in relation to three specific B vitamins: folic acid (B9), pyridoxine (B6), and cobamides (B12).

scholarly journals Intake of B vitamins in childhood and adult life in relation to psychological distress among women in a British birth cohort

2009 ◽  
Vol 12 (2) ◽  
pp. 166-174 ◽  
Author(s):  
Gita D Mishra ◽  
Sarah A McNaughton ◽  
Maria A O’Connell ◽  
Celia J Prynne ◽  
Diana Kuh
Keyword(s):  
Psychological Distress ◽  
General Health Questionnaire ◽  
Adult Life ◽  
B Vitamins ◽  
Dietary Vitamin ◽  
Vitamin B ◽  
Dietary Intakes ◽  
Food Record ◽  
B Vitamin ◽  
The Impact

AbstractBackgroundLower levels of B vitamins (particularly folate, vitamin B12and vitamin B6) may be associated with psychological distress. Little is known about the impact of childhood nutrition on psychological distress in adult life.ObjectiveWe investigated whether prospectively measured childhood and adult dietary intakes of thiamin, riboflavin, niacin, folate, vitamin B6and vitamin B12were related to the psychological distress of women in mid-age, taking into account socio-economic, behavioural and lifestyle factors.DesignProspective data were collected from a cohort of 636 British women followed up since their birth in 1946. Participants completed a 28-item, scaled version of the General Health Questionnaire (GHQ-28) to measure psychological distress at age 53 years. Dietary intakes in childhood (at age four) were determined by 24h recall and in adulthood (at age 36, 43 and 53 years) by a 5d food record.ResultsLow dietary vitamin B12intake at age 53 was associated with higher psychological distress at that age. Women in the lowest third of vitamin B12intake in adulthood had a higher GHQ-28 score compared with those in the highest third (percentage change, adjusted regression coefficient, 21 (95% CI 3, 39)). There were no other significant associations between dietary B vitamin intake in childhood or adulthood and psychological distress in the cohort.ConclusionsOverall, there is evidence that intake of vitamin B12at age 53 is related to adult psychological distress but there is no evidence for the effects of other adult B vitamin intakes or childhood intakes on psychological distress.

Methods for Restricting Maximum Exposure Rate in Computerized Adaptative Testing

Methodology ◽  
2007 ◽  
Vol 3 (1) ◽  
pp. 14-23 ◽  
Author(s):  
Juan Ramon Barrada ◽  
Julio Olea ◽  
Vicente Ponsoda
Keyword(s):  
Measurement Accuracy ◽  
Computerized Adaptive Testing ◽  
Computation Time ◽  
Adaptive Testing ◽  
Exposure Rate ◽  
Control Parameters ◽  
The Impact ◽  
Two Alternatives ◽  
Selection Of ◽  
Maximum Exposure

Abstract. The Sympson-Hetter (1985) method provides a means of controlling maximum exposure rate of items in Computerized Adaptive Testing. Through a series of simulations, control parameters are set that mark the probability of administration of an item on being selected. This method presents two main problems: it requires a long computation time for calculating the parameters and the maximum exposure rate is slightly above the fixed limit. Van der Linden (2003) presented two alternatives which appear to solve both of the problems. The impact of these methods in the measurement accuracy has not been tested yet. We show how these methods over-restrict the exposure of some highly discriminating items and, thus, the accuracy is decreased. It also shown that, when the desired maximum exposure rate is near the minimum possible value, these methods offer an empirical maximum exposure rate clearly above the goal. A new method, based on the initial estimation of the probability of administration and the probability of selection of the items with the restricted method ( Revuelta & Ponsoda, 1998 ), is presented in this paper. It can be used with the Sympson-Hetter method and with the two van der Linden's methods. This option, when used with Sympson-Hetter, speeds the convergence of the control parameters without decreasing the accuracy.

Impact of removing ESBL designation from culture reports on the selection of antibiotics for the treatment of infections associated with ESBL-producing organisms

2020 ◽  
Vol 41 (5) ◽  
pp. 604-607 ◽  
Author(s):  
Mark D. Lesher ◽  
Cory M. Hale ◽  
Dona S. S. Wijetunge ◽  
Matt R. England ◽  
Debra S. Myers ◽  
...  
Keyword(s):  
Antimicrobial Stewardship ◽  
Antibiotic Prescribing ◽  
The Impact ◽  
Inhibitor Combination ◽  
Lactamase Inhibitor ◽  
Selection Of

AbstractWe characterized the impact of removal of the ESBL designation from microbiology reports on inpatient antibiotic prescribing. Definitive prescribing of carbapenems decreased from 48.4% to 16.1% (P = .01) and β-lactam–β-lactamase inhibitor combination increased from 19.4% to 61.3% (P = .002). Our findings confirm the importance of collaboration between microbiology and antimicrobial stewardship programs.

scholarly journals The Impact of Alkaloid-Producing Epichloë Endophyte on Forage Ryegrass Breeding: A New Zealand Perspective

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 158
Author(s):  
Colin Eady
Keyword(s):  
Seed Production ◽  
Health Issues ◽  
Abiotic Stressors ◽  
Livestock Health ◽  
The Right ◽  
The Impact ◽  
The Relationship ◽  
And Storage ◽  
Selection Of ◽  
Epichloë Endophyte

For 30 years, forage ryegrass breeding has known that the germplasm may contain a maternally inherited symbiotic Epichloë endophyte. These endophytes produce a suite of secondary alkaloid compounds, dependent upon strain. Many produce ergot and other alkaloids, which are associated with both insect deterrence and livestock health issues. The levels of alkaloids and other endophyte characteristics are influenced by strain, host germplasm, and environmental conditions. Some strains in the right host germplasm can confer an advantage over biotic and abiotic stressors, thus acting as a maternally inherited desirable ‘trait’. Through seed production, these mutualistic endophytes do not transmit into 100% of the crop seed and are less vigorous than the grass seed itself. This causes stability and longevity issues for seed production and storage should the ‘trait’ be desired in the germplasm. This makes understanding the precise nature of the relationship vitally important to the plant breeder. These Epichloë endophytes cannot be ‘bred’ in the conventional sense, as they are asexual. Instead, the breeder may modulate endophyte characteristics through selection of host germplasm, a sort of breeding by proxy. This article explores, from a forage seed company perspective, the issues that endophyte characteristics and breeding them by proxy have on ryegrass breeding, and outlines the methods used to assess the ‘trait’, and the application of these through the breeding, production, and deployment processes. Finally, this article investigates opportunities for enhancing the utilisation of alkaloid-producing endophytes within pastures, with a focus on balancing alkaloid levels to further enhance pest deterrence and improving livestock outcomes.

scholarly journals An IoT-Based Participatory Antitheft System for Public Safety Enhancement in Smart Cities

Smart Cities ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 919-937
Author(s):  
Nikos Papadakis ◽  
Nikos Koukoulas ◽  
Ioannis Christakis ◽  
Ilias Stavrakas ◽  
Dionisis Kandris
Keyword(s):  
Smart Cities ◽  
Low Cost ◽  
Negative Influence ◽  
Asset Tracking ◽  
Tracking Tasks ◽  
Tracking Process ◽  
The Impact ◽  
Operation Center ◽  
Safety Enhancement ◽  
Selection Of

The risk of theft of goods is certainly an important source of negative influence in human psychology. This article focuses on the development of a scheme that, despite its low cost, acts as a smart antitheft system that achieves small property detection. Specifically, an Internet of Things (IoT)-based participatory platform was developed in order to allow asset-tracking tasks to be crowd-sourced to a community. Stolen objects are traced by using a prototype Bluetooth Low Energy (BLE)-based system, which sends signals, thus becoming a beacon. Once such an item (e.g., a bicycle) is stolen, the owner informs the authorities, which, in turn, broadcast an alert signal to activate the BLE sensor. To trace the asset with the antitheft tag, participants use their GPS-enabled smart phones to scan BLE tags through a specific smartphone client application and report the location of the asset to an operation center so that owners can locate their assets. A stolen item tracking simulator was created to support and optimize the aforementioned tracking process and to produce the best possible outcome, evaluating the impact of different parameters and strategies regarding the selection of how many and which users to activate when searching for a stolen item within a given area.

scholarly journals Simulation Verification of the Contact Parameter Influence on the Forces’ Course of Cereal Grain Impact against a Stiff Surface

2021 ◽  
Vol 11 (2) ◽  
pp. 466
Author(s):  
Włodzimierz Kęska ◽  
Jacek Marcinkiewicz ◽  
Łukasz Gierz ◽  
Żaneta Staszak ◽  
Jarosław Selech ◽  
...  
Keyword(s):  
Dynamic Properties ◽  
Decisive Role ◽  
Force Sensor ◽  
Contact Forces ◽  
Correct Selection ◽  
Contact Parameter ◽  
Cereal Grain ◽  
Wide Range ◽  
The Impact ◽  
Selection Of

The continuous development of computer technology has made it applicable in many scientific fields, including research into a wide range of processes in agricultural machines. It allows the simulation of very complex physical phenomena, including grain motion. A recently discovered discrete element method (DEM) is used for this purpose. It involves direct integration of equations of grain system motion under the action of various forces, the most important of which are contact forces. The method’s accuracy depends mainly on precisely developed mathematical models of contacts. The creation of such models requires empirical validation, an experiment that investigates the course of contact forces at the moment of the impact of the grains. To achieve this, specialised test stations equipped with force and speed sensors were developed. The correct selection of testing equipment and interpretation of results play a decisive role in this type of research. This paper focuses on the evaluation of the force sensor dynamic properties’ influence on the measurement accuracy of the course of the plant grain impact forces against a stiff surface. The issue was examined using the computer simulation method. A proprietary computer software with the main calculation module and data input procedures, which presents results in a graphic form, was used for calculations. From the simulation, graphs of the contact force and force signal from the sensor were obtained. This helped to clearly indicate the essence of the correct selection of parameters used in the tests of sensors, which should be characterised by high resonance frequency.

Does Wrongdoer Reputation Matter? Impact of Auditor-Wrongdoer Performance and Likeability Reputations on Fellow Auditors' Intention to Take Action and Choice of Reporting Outlet

2011 ◽  
Vol 23 (2) ◽  
pp. 207-234 ◽  
Author(s):  
Jesse C. Robertson ◽  
Chad M. Stefaniak ◽  
Mary B. Curtis
Keyword(s):  
Two Dimensions ◽  
Data Availability ◽  
Good Performer ◽  
Reporting Decisions ◽  
Prior Literature ◽  
Reporting Channel ◽  
Channel Preferences ◽  
Main Effects ◽  
The Impact ◽  
Selection Of

ABSTRACT We investigate the effects of auditor-wrongdoer reputations for performance and likeability on fellow auditors' intentions to take action in response to a questionable audit act. We also use this context to explore auditor selection of reporting outlets, when they do choose to take action. In an experiment with 181 auditors, main effects suggest that likeability reputation is a significant determinant of intention to take action, while performance reputation is marginally significant. As expected, interaction results indicate that auditors have the greatest intention to take action against less likeable, poor performers. Contrary to expectations, intention to take action against a more likeable, good performer is no lower than the mixed conditions. Thus, the influence of the two dimensions of reputation is complex. Additionally, we find auditors are more likely to whistle-blow internally than externally, and through non-anonymous outlets than anonymous outlets. Our contributions include exploring the impact of reputation on the actions of third parties, and advancing prior literature by considering the influence of wrongdoer attributes on reporting decisions and auditors' reporting channel preferences. Data Availability: Data are available from the first author upon request.

scholarly journals A Qualitative Study of COVID-19 Distress in University Students

2021 ◽  
pp. 216769682110251
Author(s):  
Samantha G. Farris ◽  
Mindy M. Kibbey ◽  
Erick J. Fedorenko ◽  
Angelo M. DiBello
Keyword(s):  
University Students ◽  
Undergraduate Students ◽  
Mental Health Problems ◽  
Financial Strain ◽  
Public Response ◽  
Viral Spread ◽  
Future Work ◽  
The Impact ◽  
Viral Outbreak ◽  
Selection Of

The psychological effect of the pandemic and measures taken in response to control viral spread are not yet well understood in university students; in-depth qualitative analysis can provide nuanced information about the young adult distress experience. Undergraduate students ( N = 624) in an early US outbreak “hotspot” completed an online narrative writing about the impact and distress experienced due to the COVID-19 pandemic. Data were collected April-May 2020. A random selection of 50 cases were sampled for thematic analysis. Nine themes were identified: viral outbreak distress, fear of virus contraction/transmission, proximity to virus, dissatisfaction with public response, physical distancing distress, social distancing distress, academic and school-related distress, disruptive changes in health behavior and routines, financial strain and unemployment, worsening of pre-existing mental health problems, and social referencing that minimizes distress. Future work is needed to understand the persistence of the distress, in addition to developing methods for assessment, monitoring, and mitigation of the distress.

Sign in / Sign up

Export Citation Format

Share Document