Bat attacks and moth defensive behaviour around street lights

1999 ◽  
Vol 77 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Lalita Acharya ◽  
M Brock Fenton
Keyword(s):  
Experimental Techniques ◽  
Defensive Behaviour ◽  
Naturally Occurring ◽  
Negative Effect ◽  
A Site ◽  
Observational Techniques ◽  
Ultrasound Detecting

The defensive behaviour of moths around street lights was examined at a site where bats feed heavily on moths. The lights had a negative effect on moth defensive behaviour, but a combination of observational techniques (recording the outcome of naturally occurring bat-moth interactions) and experimental techniques (deafening moths by puncturing the tympanal organs) indicated that ultrasound-detecting ears still afforded the moths some protection from bat predation. On average, bats captured 69% of the moths they attacked. Moths that exhibited evasive behaviour were caught significantly less often than those that did not (52 vs. 2%). Moths whose tympanic organs had been punctured were significantly easier to catch (requiring fewer attempts) than moths with intact ears, reflecting the fact that significantly more of the eared than the deafened moths showed evasive behaviour (48 vs. 0%). Overall, the number of captures of deafened moths was higher, though not significantly, than the number of captures of eared moths.

scholarly journals Queuine is a nutritional regulator of Entamoeba histolytica response to oxidative stress and a virulence attenuator

2020 ◽  
Author(s):  
Shruti Nagaraja ◽  
Maggi W. Cai ◽  
Jingjing Sun ◽  
Hugo Varet ◽  
Lotem Sarid ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Entamoeba Histolytica ◽  
Cysteine Proteases ◽  
Small Gtpases ◽  
Cytoskeletal Proteins ◽  
Transfer Rnas ◽  
Amebic Dysentery ◽  
Naturally Occurring ◽  
Expression Of Genes ◽  
Negative Effect

Queuosine is a naturally occurring modified ribonucleoside found in the first position of the anticodon of the transfer RNAs for Asp, Asn, His and Tyr. Eukaryotes lack pathways to synthesize queuine, the nucleobase precursor to queuosine, and must obtain it from diet or gut microbiota. Here we describe the effects of queuine on the physiology of the eukaryotic parasite, Entamoeba histolytica, the causative agent of amebic dysentery. Queuine is efficiently incorporated into E. histolytica tRNAs by a tRNA-guanine transglycosylase (EhTGT) and this incorporation stimulates the methylation of C38 in tRNAAspGUC. Queuine protects the parasite against oxidative stress (OS) and antagonizes the negative effect that oxidation has on translation by inducing the expression of genes involved in OS response, such as heat shock protein 70 (Hsp 70), antioxidant enzymes, and enzymes involved in DNA repair. On the other hand, queuine impairs E. histolytica virulence by downregulating the expression of genes previously associated with virulence, including cysteine proteases, cytoskeletal proteins, and small GTPases. Silencing of EhTGT prevents incorporation of queuine into tRNAs and strongly impairs methylation of C38 in tRNAAspGUC, parasite growth, resistance to OS, and cytopathic activity. Overall, our data reveal that queuine plays a dual role in promoting OS resistance and reducing parasite virulence.

scholarly journals Misunderstanding as a resource in interaction

Pragmatics ◽  
2017 ◽  
Vol 27 (1) ◽  
pp. 57-86 ◽  
Author(s):  
Jessica S. Robles
Keyword(s):  
Discourse Analysis ◽  
Everyday Life ◽  
Multimodal Discourse Analysis ◽  
Multimodal Discourse ◽  
Video Recordings ◽  
Activity Assessment ◽  
Naturally Occurring ◽  
A Site ◽  
A Current

The phenomenon of misunderstanding is a recurrent feature of everyday life – sometimes a source of frustration, sometimes a site of blame. But misunderstandings can also be seen as getting interactants out of (as well as into) trouble. For example, misunderstandings may be produced to deal with disaffiliative implications of ‘not being on the same page,’ and as such they may be deployed as a resource for avoiding trouble. This paper examines misunderstanding as a pragmatic accomplishment, focusing on the uses to which it is put in interactions as a practice for dealing with threats to intersubjectivity: the extent to which persons are aligned in terms of a current referent, activity, assessment, etc. A multimodal discourse analysis of audio and video recordings of naturally-occurring talk inspects moments in which misunderstandings are purported or displayed (rather than overtly invoked) as well as how such misunderstandings are oriented to as simply-repairable references, versus inferential matters more misaligned and potentially fraught. Rather than being a straightforward reflection of an experience of trouble with understanding, misunderstanding may also be collaboratively produced to manage practical challenges to intersubjectivity.

Organizational Culture in Tracked Changes

2021 ◽  
pp. 329-347
Author(s):  
Andrew Whelan
Keyword(s):  
Organizational Culture ◽  
Qualitative Data ◽  
Institutional Ethnography ◽  
Workplace Culture ◽  
Organization Of Work ◽  
Naturally Occurring ◽  
Close Analysis ◽  
Academic Workload ◽  
A Site

Tracked changes, usually thought of as preliminaries to the work documents do in organizations, are themselves an important digital residue of work, a site at which workplace culture and politics can be articulated and identified. In this chapter, I address tracked marginalia on a consequential workplace document, a draft academic workload model, as naturally occurring qualitative data. Institutional ethnography and ethnomethodology are brought to bear, respectively: to conceptualize and describe the workplace and the central role documents play in its administration; and to build up a close analysis of the strategies and positions taken by collaborators on the document, as evidenced in tracked comments. I argue that combining these analytical perspectives permits critical insights, into the local organization of work through documents and documentary processes, and the affordances of tracked changes as a communicative backchannel.

Effects of pitch canker pathogen on gallery excavation and oviposition by Ips paraconfusus (Coleoptera: Scolytidae)

2002 ◽  
Vol 134 (4) ◽  
pp. 519-528 ◽  
Author(s):  
Andrew J. Storer ◽  
David L. Wood ◽  
Thomas R. Gordon
Keyword(s):  
Pinus Radiata ◽  
Ips Paraconfusus ◽  
Multiple Infections ◽  
Pitch Canker ◽  
Fusarium Circinatum ◽  
Monterey Pine ◽  
Naturally Occurring ◽  
Canker Pathogen ◽  
Negative Effect ◽  
The Mean

AbstractIps paraconfusus Lanier is a vector of the pitch canker fungus, Fusarium circinatum Nirenberg and O’Donnell, in California. Multiple infections of Monterey pine, Pinus radiata D. Don. (Pinaceae), branches and main stems appear to predispose trees to infestation by I. paraconfusus. The effect of cankers produced in response to F. circinatum on oviposition and gallery construction was investigated. Introduction of beetles into artificially induced or naturally occurring cankers was less likely to result in oviposition and resulted in shorter galleries than introductions into logs without cankers. Of all adults that produced eggs, the mean number of eggs per adult was no different in logs with cankers than in canker-free logs; however, the distance across the grain from the introduction point to the first egg was greater for adults introduced into cankers than for adults introduced away from cankers. These results indicate that the pitch canker pathogen has a negative effect on I. paraconfusus, as cankers produced in response to the pathogen are unsuitable for exploitation by the insect.

scholarly journals Structural Basis of APH(3′)-IIIa-Mediated Resistance to N1-Substituted Aminoglycoside Antibiotics

2009 ◽  
Vol 53 (7) ◽  
pp. 3049-3055 ◽  
Author(s):  
Desiree H. Fong ◽  
Albert M. Berghuis
Keyword(s):  
Crystal Structure ◽  
Bacterial Resistance ◽  
Aminoglycoside Antibiotics ◽  
Structural Basis ◽  
Amino Group ◽  
Naturally Occurring ◽  
Type Iiia ◽  
Bactericidal Properties ◽  
A Site ◽  
Binding Loop

ABSTRACT Butirosin is unique among the naturally occurring aminoglycosides, having a substituted amino group at position 1 (N1) of the 2-deoxystreptamine ring with an (S)-4-amino-2-hydroxybutyrate (AHB) group. While bacterial resistance to aminoglycosides can be ascribed chiefly to drug inactivation by plasmid-encoded aminoglycoside-modifying enzymes, the presence of an AHB group protects the aminoglycoside from binding to many resistance enzymes, and hence, the antibiotic retains its bactericidal properties. Consequently, several semisynthetic N1-substituted aminoglycosides, such as amikacin, isepamicin, and netilmicin, were developed. Unfortunately, butirosin, amikacin, and isepamicin are not resistant to inactivation by 3′-aminoglycoside O-phosphotransferase type IIIa [APH(3′)-IIIa]. We report here the crystal structure of APH(3′)-IIIa in complex with an ATP analog, AMPPNP [adenosine 5′-(β,γ-imido)triphosphate], and butirosin A to 2.4-Å resolution. The structure shows that butirosin A binds to the enzyme in a manner analogous to other 4,5-disubstituted aminoglycosides, and the flexible antibiotic-binding loop is key to the accommodation of structurally diverse substrates. Based on the crystal structure, we have also constructed a model of APH(3′)-IIIa in complex with amikacin, a commonly used semisynthetic N1-substituted 4,6-disubstituted aminoglycoside. Together, these results suggest a strategy to further derivatize the AHB group in order to generate new aminoglycoside derivatives that can elude inactivation by resistance enzymes while maintaining their ability to bind to the ribosomal A site.

scholarly journals Towards a Safe and Respectful Campus: Perspectives of Multicultural Education

2018 ◽  
Vol 5 (2) ◽  
Author(s):  
Hsuan-Jen Chen
Keyword(s):  
Multicultural Education ◽  
Power Relations ◽  
Campus Culture ◽  
Multiple Perspectives ◽  
Safe Environment ◽  
Multicultural Issues ◽  
Negative Effect ◽  
A Site

This paper argues that multicultural education is an essential way of creating a safe and respectful campus. Examined from the perspective of power relations, schools are viewed as a site that helps maintain existing power relations by reinforcing the assimilation ideology. A drawback of this is that only one set of perspectives is valued. As a result, students who are not part of the norm are more likely to be treated unfairly in school. This may impose a negative effect on their learning as school is not a safe environment for them. To create a safe and respectful campus, multicultural education has to be incorporated as it helps students foster multiple perspectives and learn to embrace diversity. This paper first defines multicultural education. Secondly, it illustrates why multicultural issues should be examined in the framework of power relations. Then, it focuses on exploring the assimilation ideology and the role schools play in the process of assimilation. In this section, it analyzes how students are endangered by assimilation, and the case of the Yeh Yong-Zi event in Taiwan is also examined. Finally, it discusses in what ways multicultural education could help establish a safe and respectful campus culture.

scholarly journals Erythrocytes Prevent Degradation of Carnosine by Human Serum Carnosinase

2021 ◽  
Vol 22 (23) ◽  
pp. 12802
Author(s):  
Henry Oppermann ◽  
Stefanie Elsel ◽  
Claudia Birkemeyer ◽  
Jürgen Meixensberger ◽  
Frank Gaunitz
Keyword(s):  
Oxidative Stress ◽  
Human Serum ◽  
Food Supplement ◽  
Aging Effects ◽  
Atp Production ◽  
Beneficial Effects ◽  
Naturally Occurring ◽  
Negative Effect ◽  
Improve Exercise Performance ◽  
First Time

The naturally occurring dipeptide carnosine (β-alanyl-l-histidine) has beneficial effects in different diseases. It is also frequently used as a food supplement to improve exercise performance and because of its anti-aging effects. Nevertheless, after oral ingestion, the dipeptide is not detectable in human serum because of rapid degradation by serum carnosinase. At the same time, intact carnosine is excreted in urine up to five hours after intake. Therefore, an unknown compartment protecting the dipeptide from degradation has long been hypothesized. Considering that erythrocytes may constitute this compartment, we investigated the uptake and intracellular amounts of carnosine in human erythrocytes cultivated in the presence of the dipeptide and human serum using liquid chromatography–mass spectrometry. In addition, we studied carnosine’s effect on ATP production in red blood cells and on their response to oxidative stress. Our experiments revealed uptake of carnosine into erythrocytes and protection from carnosinase degradation. In addition, no negative effect on ATP production or defense against oxidative stress was observed. In conclusion, our results for the first time demonstrate that erythrocytes can take up carnosine, and, most importantly, thereby prevent its degradation by human serum carnosinase.

170 NATURALLY OCCURRING CHRONIC MASTITIS COMPROMISES FOLLICULOGENESIS, AFFECTS VASCULARIZATION, AND INTERACTS WITH DIFFERENTIATION FACTOR GDF-9 IN BOVINE OVARIAN STROMA

2011 ◽  
Vol 23 (1) ◽  
pp. 187
Author(s):  
M. M. Rahman ◽  
M. Mazilli ◽  
G. Pennarossa ◽  
T. A. L. Brevini ◽  
A. Vanelli ◽  
...  
Keyword(s):  
Ovarian Function ◽  
Statistical Significance ◽  
Exact Test ◽  
Milk Samples ◽  
Naturally Occurring ◽  
Negative Effect ◽  
Strong Staining ◽  
Follicle Differentiation ◽  
National Mastitis Council ◽  
Major Pathogens

Recent studies have suggested an association between reproductive failure and mastitis in lactating dairy cows, but our understanding of how mastitis affects reproduction is still limited. In the present study we investigated the effects of naturally occurring chronic mastitis on the population dynamics of ovarian follicles. Ovaries and milk samples were collected from 74 cows at slaughter. Milk samples from each quarter, were analyzed following National Mastitis Council procedures. Based on the presence of major pathogens and somatic cell count results, animals were sorted in 9 groups, but only the 2 extremes were considered for further analysis: uninfected (n = 8) and affected by chronic mastitis (n = 9). Primordial, primary, and secondary follicles were counted and scored on similar surface area of ovary sections for each animal (mean ± SD = 5.65 ± 0.25 cm2). They were analyzed with Fisher’s exact test, and the association between health status and follicle number was estimated by odds ratios ± confidence limits. Vasculature area in the ovarian cortex of healthy and mastitic animals was identified using Bandeiraea simplicifolia-I lectin (BSL-I). Results were quantified with the dedicated software MacBiophotonics image J, NIH, USA, and subsequently analyzed with t-test for statistical significance. Follicles were further characterized by immunostaining with a GDF-9-specific antibody. The intensity of the staining was semi-quantified using a relative scale: 0, 1, and 2 for no, weak, and strong staining, respectively. Our results indicate no (P > 0.05) difference between the numbers of primordial and primary follicles in healthy and affected animals. In contrast, the number of secondary follicles was significantly lower in sick animals (odds ratio 10.50*; P < 0.05), indicating 10 times higher risk for a mastitic animal to have less than 2 secondary follicles per square centimeter. Ovarian stromal vasculature represented the 6.38 ± 0.66% of cortical area in healthy animals v. 4.24 ± 0.37% (P < 0.001) in affected cows. The GDF-9 immunostaining revealed decreased fluorescence intensity in mastitic animals. Our results show that chronic mastitis is associated with considerable alterations in follicle growth and differentiation with a decreased ability of primary follicles to develop into the secondary state in affected animals. This is accompanied by a significant decrease of ovarian vasculature and the down-regulation of the follicle differentiation-associated factor GDF. The present findings substantiate the hypothesis that mastitis can reduce fertility by exerting a negative effect on ovarian function.

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