3,030 research outputs found
Screening of Irish Fruit and Vegetable Germplasm for Novel Anti-tumour and Pesticidal Compounds
Conference paperPhytochemicals are a rich source of novel therapeutic and insecticidal agents (McLaughlin and Chang, 1999). Considerable research effort has been directed at
screening exotic and medicinal plants in the search for novel products. However, plants which have traditional food uses have been little explored. In addition the
range, type and level of individual bioactive compounds can vary significantly between different species, different cultivars of the same species and different
tissue types of the plant (Reilly, in press) Therefore, the
objective of this study was to screen a range of fruits and vegetables which can be grown in Ireland for novel bioactive compounds for use in food production and as bio-pesticides.The author wishes to acknowledge the financial support from the Dublin Institute of Technology through an ABBEST fellowshi
Bioactive Natural Products
Bioactive natural products have never ceased to play an important role in the search of novel therapeutic agents. Natural products from the nature such as the plant and marine sources form an integral part of the living system, and they have existed ever since the beginning of life. Therefore, it is undeniable that works related to natural products continue to develop in many aspects involving researchers from various scientific backgrounds. This special issue is dedicated to compile twelve articles on chemical and biological aspects of research developments in natural products
In vitro activity of bedaquiline against rapidly growing nontuberculous mycobacteria
Bedaquiline (BDQ) has been proven to be effective in the treatment of multidrug-resistant tuberculosis. We hypothesized that BDQ could be a potential agent to treat nontuberculous mycobacterial (NTM) infection. The objective of this study was to evaluate the in vitro activity of BDQ against rapidly growing mycobacteria by assessing the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) against 18 NTM strains. For MIC determination we performed the resazurin microtitre assay broth dilution, and for the MBC the c.f.u. was determined. BDQ exhibited a strong inhibitory effect against most NTM tested; however, for some NTM strains the MBC was significantly higher than the MIC. A new finding is that Mycobacterium flavescens has a mutation in the gene atpE associated with natural resistance to BDQ. These preliminary promising results demonstrate that BDQ could be potentially useful for the treatment of NTM
The transcriptome of Mycobacterium tuberculosis in a lipid-rich dormancy model through RNAseq analysis
Tuberculosis (TB) is currently the number one killer among infectious diseases worldwide. Lipids are abundant molecules during the infectious cycle of Mycobacterium tuberculosis (Mtb) and studies better mimicking its actual metabolic state during pathogenesis are needed. Though most studies have focused on the mycobacterial lipid metabolism under standard culture conditions, little is known about the transcriptome of Mtb in a lipid environment. Here we determined the transcriptome of Mtb H37Rv in a lipid-rich environment (cholesterol and fatty acid) under aerobic and hypoxic conditions, using RNAseq. Lipids significantly induced the expression of 368 genes. A main core lipid response was observed involving efflux systems, iron caption and sulfur reduction. In co-expression with ncRNAs and other genes discussed below, may act coordinately to prepare the machinery conferring drug tolerance and increasing a persistent population. Our findings could be useful to tag relevant pathways for the development of new drugs, vaccines and new strategies to control TB
Using First Passage Time Analysis to Identify Foraging Patterns of the Northern Bobwhite
Patterns in movement data can reveal important information relating environmental variables to behavioral mechanisms. First passage time analysis (hereafter; FPT) can be used to quantify the spatial and temporal variation in movements by identifying areas of restricted search behavior based on measuring residence time in an area. It is applicable in studies of foraging ecology and habitat selection because it can empirically quantify behavioral decisions without any a priori assumptions of habitat availability. Furthermore, FPT analysis is simple to implement and interpret; however, the technique has yet to be applied to the northern bobwhite (Colinus virginianus, hereafter bobwhite) because telemetry locations in short (e.g., 30 min) successive time intervals are needed. Our primary objective was to better understand patterns in foraging behavior of bobwhites as it relates to habitat use and improve management. Our secondary objective was to test the efficiency of using FPT analysis on telemetry data collected at different time intervals. Bobwhites were captured during the fall of 2013 and 2014 on a private plantation in South Carolina and fitted with very high frequency (VHF) transmitters (n = 143 and n = 148, respectively). We located coveys at 1 hour (2013) and 30 (2014) minute time intervals during daylight. Bobwhites concentrated their searching efforts to a few hours pre-dusk. Search efforts were proximal to supplemental food sources, with some intra-seasonal variation. Advances in global positioning system (GPS) technology will likely increase opportunities for collecting fine-scale movement data for bobwhites. Understanding techniques such as FPT analysis will enhance our knowledge of northern bobwhite ecology and management
Refining the Hunting Zone of Hunter-Covey Interface Models
Regulating harvest is important to sustain northern bobwhite (Colinus virginianus) populations. Direct measures to control harvest such as setting fixed proportions (i.e., percent of fall population) are not typically feasible, thus, indirect measures (e.g., managing access, season length) are more commonly used. However, these measures are predicated on relationships between hunter effort and kill rate (K) which is a function of several parameters including: the probability of encountering a covey (p), where p is a function of the effective area hunted (a) divided by that available (A). Thus, a, is a product of the velocity of hunter movement (v), hours spent hunting (h), and the effective width of the hunting zone (w). Velocity and hours spent hunting are easy to quantify, however, estimating w is more difficult and to-date not undertaken. We focused on w, specifically wded, the distance a dog detects a covey assuming the covey is stationary. We assume stationarity such that evasive behaviors can be estimated separately from the olfaction process. The objective of our experiments was to estimate the influence of weather on wded. We used pen-raised bobwhites placed about 150 meters apart to simulate hunts (n = 13) on two study sites. A handler guided a single birddog through the course, downwind from birds, and recorded the distance from the pointed dog to caged birds. Dogs pointed birds (n = 236) at an average distance of 6.2 m (SD = 4.2). Wind speed was positively associated with detection distance (r = 0.19, P \u3c 0.01), while temperature was negatively associated (r = -0.18, P \u3c 0.05). The hunter-covey interface is a dynamic process driven by a myriad of factors. Our results suggest simple weather parameters influence the effective area hunted, therefore, affecting the kill rate that managers want to control
Hunter-Covey Interactions Using Pointing Bird Dogs
Hunting northern bobwhites (Colinus virginianus) with pointing dogs is a long-standing tradition in the Southeastern United States. Despite this rich hunting legacy, a paucity of empirical, behavioral information exists on the interaction between bobwhite coveys, pointing dogs and humans. As such, the efficiency of using pointing dogs to locate bobwhite coveys or an individual covey’s behavioral response to hunting is poorly understood. During 2013 – 2015, we conducted hunts (n = 192) by mode of foot on Tall Timbers Research Station (TTRS, ~1,570 ha) in Leon County, Florida and horseback on a private property (2,023 ha) in Georgetown County, South Carolina. We captured bobwhites (n = 741) and fitted them with activity-switch enabled radio-transmitters, and we tracked coveys prior to, during and after hunts. We used 2 types of global positioning system (GPS) units to collect route data from dogs and hunters (via horseback or foot). We recorded encounter information (e.g., behavior, encounter type such as covey point or wild flush) in the field using a pre-configured application on an iPad and linked spatial data using a geographic information system (i.e., ArcGIS). On average, 52% of all radio-tagged coveys were available (within a dog’s scent radius) during a hunt of which 73% were detected by pointing bird dogs. The overall probability of observing a covey on a hunt was 38% suggesting that most coveys within a hunting course go undetected. Vegetation density did not appear to be an impediment to bobwhite mobility or an important factor in detection of coveys by bird dogs. The potential reduction or manipulation of existing habitats may help to constrain where bobwhite coveys can escape to and covertly improve hunting efficiency. Furthermore, our results imply that a relatively high bobwhite density is required for sportsman to frequently encounter bobwhite coveys during a hunt
How Humans Judge Machines
How people judge humans and machines differently, in scenarios involving natural disasters, labor displacement, policing, privacy, algorithmic bias, and more. How would you feel about losing your job to a machine? How about a tsunami alert system that fails? Would you react differently to acts of discrimination depending on whether they were carried out by a machine or by a human? What about public surveillance? How Humans Judge Machines compares people's reactions to actions performed by humans and machines. Using data collected in dozens of experiments, this book reveals the biases that permeate human-machine interactions. Are there conditions in which we judge machines unfairly? Is our judgment of machines affected by the moral dimensions of a scenario? Is our judgment of machine correlated with demographic factors such as education or gender? CĂ©sar Hidalgo and colleagues use hard science to take on these pressing technological questions. Using randomized experiments, they create revealing counterfactuals and build statistical models to explain how people judge artificial intelligence and whether they do it fairly. Through original research, How Humans Judge Machines bring us one step closer to understanding the ethical consequences of AI. Written by CĂ©sar A. Hidalgo, the author of Why Information Grows and coauthor of The Atlas of Economic Complexity (MIT Press), together with a team of social psychologists (Diana Orghian and Filipa de Almeida) and roboticists (Jordi Albo-Canals), How Humans Judge Machines presents a unique perspective on the nexus between artificial intelligence and society. Anyone interested in the future of AI ethics should explore the experiments and theories in How Humans Judge Machines
Engineering Students as Co-creators in an Ethics of Technology Course
Research on the effectiveness of case studies in teaching engineering ethics in higher education is underdeveloped. To add to our knowledge, we have systematically compared the outcomes of two case approaches to an undergraduate course on the ethics of technology: a detached approach using real-life cases and a challenge-based learning (CBL) approach with students and stakeholders acting as co-creators (CC). We first developed a practical typology of case-study approaches and subsequently tested an evaluation method to assess the students’ learning experiences (basic needs and motivation) and outcomes (competence development) and staff interpretations and operationalizations, seeking to answer three questions: (1) Do students in the CBL approach report higher basic needs, motivation and competence development compared to their peers in the detached approach? (2) What is the relationship between student-perceived co-creation and their basic needs, motivation and competence development? And (3) what are the implications of CBL/CC for engineering-ethics teaching and learning? Our mixed methods analysis favored CBL as it best supported teaching and research goals while satisfying the students’ basic needs and promoting intrinsic motivation and communication competences. Competence progress in other areas did not differ between approaches, and motivation in terms of identified regulation was lower for CBL, with staff perceiving a higher workload. We propose that our case typology model is useful and that as a method to engage students as co-creators, CBL certainly merits further development and evaluation, as does our effectiveness analysis for engineering ethics instruction in general and for case-study approaches in particular
Children of prisoners: exploring the impact of families' reappraisal of the role and status of the imprisoned parent on children's coping strategies
Qualitative data from a larger study on the impact of parental imprisonment in four countries found that children of prisoners face fundamentally similar psychological and social challenges. The ways that children cope, however, are influenced by the interpretative frame adopted by the adults around them, and by how issues of parental imprisonment are talked about in their families. This article argues that families have to reappraise their view of the imprisoned parent and then decide on their policy for how to deal with this publicly. Their approach may be based on openness and honesty or may emphasise privacy and secrecy, or a combination of these. Children are likely to be influenced by their parents'/carers' views, although these may cause conflict for them. Where parents/carers retain a positive view of the imprisoned parent, children are likely to benefit; where parents/carers feel issues of shame and stigma acutely, this is likely to be transmitted to their children. This is important for social workers and practitioners involved in supporting prisoners' families and for parenting programmes
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