Off-Flavours in Aquatic Ecosystems – An Introduction

1983 ◽  
Vol 15 (6-7) ◽  
pp. 1-11 ◽  
Author(s):  
Per-Edvin Persson
Keyword(s):  
Natural Waters ◽  
Biological Research ◽  
Sensory Response ◽  
Future Research ◽  
Screening Methods ◽  
Complete Understanding ◽  
Sensory Assessment ◽  
Odour Threshold ◽  
Micro Organisms

The significance of off-flavours in water and fisheries management is briefly discussed, as are guidelines for future research. In order to elucidate the sources and causes of off-flavours in natural waters, an integration of sensory, chemical and biological research is needed. Sensory characterization of off-flavours often involves taste and odour threshold measurements. Current techniques at water works are critically discussed. The need for a more comprehensive approach, where sensory response is related to stimulus intensity over a large range of magnitudes, is stressed. The use of consumer panels in sensory assessment of water quality is advocated. Sensory methods are useful screening methods. Chemical analyses should be related to the sensory characteristics of the compounds analyzed. Recent research on biogenic off-flavours in natural waters have indicated that they are more, complex than originally conceived. Criteria for establishing the odour production by organisms are presented. Compilations of scientifically proved taste and odour producing algae and micro-organisms may be useful, but more research is needed on the reasons for variability of their odour production. The development of relevant abatement techniques depends on a more complete understanding of the etiology of off-flavours in natural waters.

scholarly journals About the dangers, costs and benefits of living an aerobic lifestyle

2014 ◽  
Vol 42 (4) ◽  
pp. 917-921 ◽  
Author(s):  
Daniela Knoefler ◽  
Lars I.O. Leichert ◽  
Maike Thamsen ◽  
Claudia M. Cremers ◽  
Dana Reichmann ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
Research Programme ◽  
Future Research ◽  
Mammalian Host ◽  
Costs And Benefits ◽  
Cellular Processes ◽  
Effective Antioxidant ◽  
Development And Differentiation ◽  
Micro Organisms

The era in which ROS (reactive oxygen species) were simply the ‘bad boys of biology’ is clearly over. High levels of ROS are still rightfully considered to be toxic to many cellular processes and, as such, contribute to disease conditions and cell death. However, the high toxicity of ROS is also extremely beneficial, particularly as it is used to kill invading micro-organisms during mammalian host defence. Moreover, a transient, often more localized, increase in ROS levels appears to play a major role in signal transduction processes and positively affects cell growth, development and differentiation. At the heart of all these processes are redox-regulated proteins, which use oxidation-sensitive cysteine residues to control their function and by extension the function of the pathways that they are part of. Our work has contributed to changing the view about ROS through: (i) our characterization of Hsp33 (heat-shock protein 33), one of the first redox-regulated proteins identified, whose function is specifically activated by ROS, (ii) the development of quantitative tools that reveal extensive redox-sensitive processes in bacteria and eukaryotes, and (iii) the discovery of a link between early exposure to oxidants and aging. Our future research programme aims to generate an integrated and system-wide view of the beneficial and deleterious effects of ROS with the central goal to develop more effective antioxidant strategies and more powerful antimicrobial agents.

Parasite defense mechanisms in bees: behavior, immunity, antimicrobials, and symbionts

2019 ◽  
Vol 4 (1) ◽  
pp. 59-76 ◽  
Author(s):  
Alison E. Fowler ◽  
Rebecca E. Irwin ◽  
Lynn S. Adler
Keyword(s):  
Defense Mechanisms ◽  
Poor Quality ◽  
Future Research ◽  
Immune Priming ◽  
Social Bees ◽  
Bee Health ◽  
Landscape Scales ◽  
And Function ◽  
Solitary Species

Parasites are linked to the decline of some bee populations; thus, understanding defense mechanisms has important implications for bee health. Recent advances have improved our understanding of factors mediating bee health ranging from molecular to landscape scales, but often as disparate literatures. Here, we bring together these fields and summarize our current understanding of bee defense mechanisms including immunity, immunization, and transgenerational immune priming in social and solitary species. Additionally, the characterization of microbial diversity and function in some bee taxa has shed light on the importance of microbes for bee health, but we lack information that links microbial communities to parasite infection in most bee species. Studies are beginning to identify how bee defense mechanisms are affected by stressors such as poor-quality diets and pesticides, but further research on this topic is needed. We discuss how integrating research on host traits, microbial partners, and nutrition, as well as improving our knowledge base on wild and semi-social bees, will help inform future research, conservation efforts, and management.

scholarly journals Crowdsourcing and open innovation: a systematic literature review, an integrated framework and a research agenda

2021 ◽  
Author(s):  
Livio Cricelli ◽  
Michele Grimaldi ◽  
Silvia Vermicelli
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Open Innovation ◽  
Innovation Management ◽  
Academic Research ◽  
Future Research ◽  
Four Dimensions ◽  
Word Analysis ◽  
The Relationship

AbstractIn recent years, Open Innovation (OI) and crowdsourcing have been very popular topics in the innovation management literature, attracting significant interest and attention, and inspiring a rich production of publications. Although these two topics share common themes and address similar managerial challenges, to the best of our knowledge, there is no systematic literature review that digs deep into the intersection of both fields. To fill in this gap a joint review of crowdsourcing and OI topics is both timely and of interest. Therefore, the main objective of this study is to carry out a comprehensive, systematic, and objective review of academic research to help shed light on the relationship between OI and crowdsourcing. For this purpose, we reviewed the literature published on these two topics between 2008 and 2019, applying two bibliometric techniques, co-citation and co-word analysis. We obtained the following results: (i) we provide a qualitative analysis of the emerging and trending themes, (ii) we discuss a characterization of the intersection between OI and crowdsourcing, identifying four dimensions (strategic, managerial, behavioral, and technological), (iii) we present a schematic reconceptualization of the thematic clusters, proposing an integrated view. We conclude by suggesting promising opportunities for future research.

Ferrous materials degradation: characterisation of rust by colour – an overview

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Desmond E. P. Klenam ◽  
Michael O. Bodunrin ◽  
Stefania Akromah ◽  
Emmanuel Gikunoo ◽  
Anthony Andrews ◽  
...  
Keyword(s):  
Yellow Rust ◽  
Brown Rust ◽  
Future Research ◽  
Stable Form ◽  
Low Oxygen ◽  
High Moisture ◽  
Oxygen Environment ◽  
Causative Factors ◽  
Analytical Tools

Abstract An overview of the characterisation of rust by colour is presented. Each distinct rust colour is caused by atmospheric impurities, high or low moisture content and high or low oxygen environment over time. Yellow rust is mainly due to the high moisture environment over a period of time, which drips. Brown rust is dry, crusty and due to water and oxygen contact with localised patches on component surfaces. Black rust, the most stable form, occurs in low moisture and low oxygen environment. The rust residue shows where the reaction started, especially in contact with chlorides. The causative factors of red rust are atmospheric and similar to black rust in a chloride-containing environment. The effect of packaging, manufacturing and environmental factors on rust colour is briefly discussed. Visual characterization of rust could pre-empt root causes and analytical tools for validation. The limitations of these concepts are mentioned and directions for future research highlighted.

scholarly journals Scope of Artificial Intelligence in Screening and Diagnosis of Colorectal Cancer

2020 ◽  
Vol 9 (10) ◽  
pp. 3313 ◽  
Author(s):  
Hemant Goyal ◽  
Rupinder Mann ◽  
Zainab Gandhi ◽  
Abhilash Perisetti ◽  
Aman Ali ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Colorectal Cancer ◽  
Cancer Screening ◽  
Colorectal Cancer Screening ◽  
Narrow Band Imaging ◽  
Screening Methods ◽  
Polyp Detection ◽  
Mortality And Morbidity ◽  
Magnifying Chromoendoscopy

Globally, colorectal cancer is the third most diagnosed malignancy. It causes significant mortality and morbidity, which can be reduced by early diagnosis with an effective screening test. Integrating artificial intelligence (AI) and computer-aided detection (CAD) with screening methods has shown promising colorectal cancer screening results. AI could provide a “second look” for endoscopists to decrease the rate of missed polyps during a colonoscopy. It can also improve detection and characterization of polyps by integration with colonoscopy and various advanced endoscopic modalities such as magnifying narrow-band imaging, endocytoscopy, confocal endomicroscopy, laser-induced fluorescence spectroscopy, and magnifying chromoendoscopy. This descriptive review discusses various AI and CAD applications in colorectal cancer screening, polyp detection, and characterization.

scholarly journals Biotic and Abiotic Factors Influencing Arsenic Biogeochemistry and Toxicity in Fluvial Ecosystems: A Review

2020 ◽  
Vol 17 (7) ◽  
pp. 2331
Author(s):  
Laura Barral-Fraga ◽  
María Teresa Barral ◽  
Keeley L. MacNeill ◽  
Diego Martiñá-Prieto ◽  
Soizic Morin ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Arsenic Exposure ◽  
Inorganic Arsenic ◽  
Future Research ◽  
Strong Impact ◽  
Trophic Relations ◽  
Fluvial Systems ◽  
Pampean Streams ◽  
Micro Organisms ◽  
Different Origins

This review is focused on the biogeochemistry of arsenic in freshwaters and, especially, on the key role that benthic microalgae and prokaryotic communities from biofilms play together in through speciation, distribution, and cycling. These microorganisms incorporate the dominant iAs (inorganic arsenic) form and may transform it to other arsenic forms through metabolic or detoxifying processes. These transformations have a big impact on the environmental behavior of arsenic because different chemical forms exhibit differences in mobility and toxicity. Moreover, exposure to toxicants may alter the physiology and structure of biofilms, leading to changes in ecosystem function and trophic relations. In this review we also explain how microorganisms (i.e., biofilms) can influence the effects of arsenic exposure on other key constituents of aquatic ecosystems such as fish. At the end, we present two real cases of fluvial systems with different origins of arsenic exposure (natural vs. anthropogenic) that have improved our comprehension of arsenic biogeochemistry and toxicity in freshwaters, the Pampean streams (Argentina) and the Anllóns River (Galicia, Spain). We finish with a briefly discussion of what we consider as future research needs on this topic. This work especially contributes to the general understanding of biofilms influencing arsenic biogeochemistry and highlights the strong impact of nutrient availability on arsenic toxicity for freshwater (micro) organisms.

Production of Bio Gas from Vegetable and Flowers Wastes Using Anaerobic Digestion

2015 ◽  
Vol 787 ◽  
pp. 803-808 ◽  
Author(s):  
A. Deepanraj ◽  
S. Vijayalakshmi ◽  
J. Ranjitha
Keyword(s):  
Anaerobic Digestion ◽  
Biogas Production ◽  
Research Work ◽  
Pressure Gauge ◽  
Pig Manure ◽  
Future Research ◽  
Digital Pressure ◽  
Vegetable Wastes ◽  
Main Component

The present research paper describes about the anaerobic digestion of vegetable (Banana, Cauliflower, potato, and sweet potato) and flower wastes (Rose, sambangi, gulmohar, marigold, golden shower tree, silk tree mimosa) in a 1L capacity of anaerobic digestor using pig manure as an inoculums. The digester was operated in the ratio of 1:1 of substrate to inoculums at RT. The substrate concentrations are varied such as 5%, 7%, and 10% was used and amount of gas produced was analysed using digital pressure gauge. The results obtained showed that, marigold flower had given higher yield of biogas than vegetable wastes and the digestion period was less. The average biogas production potential of withered flowers was observed as 14.36 g/kg in 5 days, where in case of vegetable wastes it was 10.0234 g/kg in 6 days. The study showed that flowers which are available in abundant in India is thrown away within a day, in the environment. These feedstocks are good feed stock for the production of biogas. The generation of biogas from flowers and vegetable waste upholds the concept of waste to wealth in enhancing sustainability of development. The future research work is mainly focused on the characterization of the main component present in the bio-gas using sophisticated instruments.

The Ismaili Tradition in Iran: 13th Century to the Present

2021 ◽  
Author(s):  
Daniel Beben
Keyword(s):  
20Th Century ◽  
Future Research ◽  
Early 20Th Century ◽  
13Th Century ◽  
Complete Understanding ◽  
Northern Iran ◽  
Minority Community ◽  
History Of ◽  
The 19Th Century ◽  
To Receive

The Ismailis are a minority community of Shiʿi Muslims that first emerged in the 8th century. Iran has hosted one of the largest Ismaili communities since the earliest years of the movement and from 1095 to 1841 it served as the home of the Nizārī Ismaili imams. In 1256 the Ismaili headquarters at the fortress of Alamūt in northern Iran was captured by the Mongols and the Imam Rukn al-Dīn Khūrshāh was arrested and executed, opening a perilous new chapter in the history of the Ismailis in Iran. Generations of observers believed that the Ismailis had perished entirely in the course of the Mongol conquests. Beginning in the 19th century, research on the Ismailis began to slowly reveal the myriad ways in which they survived and even flourished in Iran and elsewhere into the post-Mongol era. However, scholarship on the Iranian Ismailis down to the early 20th century remained almost entirely dependent on non-Ismaili sources that were generally quite hostile toward their subject. The discovery of many previously unknown Ismaili texts beginning in the early 20th century offered prospects for a richer and more complete understanding of the tradition’s historical development. Yet despite this, the Ismaili tradition in the post-Mongol era continues to receive only a fraction of the scholarly attention given to earlier periods, and a number of sources produced by Ismaili communities in this period remain unexplored, offering valuable opportunities for future research.

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