Pyridaben is a mitochondrial electron transport complex I inhibitor. The H110R mutation in the PSST subunit has been reported as a major factor in pyridaben resistance in the two-spotted spider mite, ...Tetranychus urticae. However, backcross experiments revealed that the mutant PSST alone conferred only moderate resistance. In contrast, inhibition of cytochrome P450 (CYP) markedly reduces resistance levels in a number of highly resistant strains. It was reported previously that maternal factors contributed to the inheritance of pyridaben resistance in the egg stage, but the underlying mechanisms have yet to be elucidated. Here, we studied the combined effects of the PSST H110R mutation and candidate CYPs, as metabolic resistance factors, on pyridaben resistance in T. urticae. We found that the maternal effects of inheritance of resistance in the egg stage were associated with CYP activity. Analysis of differential gene expression by RNA-seq identified CYP392A3 as a candidate causal factor for the high resistance level. Congenic strains, where the alleles of both PSST and CYP392A3 were derived from a resistant strain (RR_i; i = 1 or 2) and a susceptible strain (SS_i) in a common susceptible genetic background, were constructed by marker-assisted backcrossing. RR_i showed upregulation of CYP392A3 and high resistance levels (LC50 > 10,000 mg L−1), while SS_i had LC50 < 10 mg L−1. To disentangle the individual effects of PSST and CYP392A3 alleles, we also attempted to uncouple these genes in RR_i. We conclude that given the variation in LC50 values and expression levels of CYP392A3 in the congenic and uncoupled strains, it is likely that the high pyridaben resistance levels are due to a synergistic or cumulative effect of the combination of mutant PSST and associated CYPs, including CYP392A3, but other yet to be discovered factors cannot be excluded.
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•PSST mutation confers moderate pyridaben resistance in Tetranychus urticae.•We found mutant PSST and associated CYPs conferred the high resistance levels.•CYP392A3 was identified as a candidate, but other factors cannot be excluded.•High resistance is probably due to a synergistic or cumulative effect of factors.
Tetranychus urticae is an extremely generalist herbivore that can cause serious yield losses in various plants, including beans. Although alternative control options are present to control T. urticae ...populations in greenhouses, such as biological control, the control of spider mites in open fields has largely relied on chemical pesticides. Determination of resistance status and resistance mechanisms underlying the decreasing susceptibility is of vital importance to design a robust integrated resistance management program. Up to 9- and 15-fold resistance ratios to abamectin and pyridaben, respectively, were determined based on LC
50
values. Abamectin showed excellent efficacy, whereas pyridaben application would cause control failure in more than half of the tested populations under suitable spraying conditions. Therefore, the use of pyridaben should be in rotation with other acaricides belonging to different mode of action groups. None of the populations harboured the point mutations at the target sites of abamectin and pyridaben. For the first time, resistance monitoring in T. urticae populations against pyridaben was determined in Turkey, despite its long usage history.
The citrus red mite, Panonychus citri, is a major pest on citrus all around the world. Mitochondrial Electron Transport Inhibitors of complex I (METI-I) acaricides such as fenpyroximate have been ...used extensively to control P. citri populations, which resulted in multiple reports of METI-I resistant populations in the field. In this study, biochemical and molecular mechanisms of fenpyroximate resistance were investigated in P. citri. Seven populations were collected from Northern provinces of Iran. Resistance ratios were determined and reached up to 75-fold in comparison to a fenpyroximate susceptible population. Cross-resistance to two additional METI-I acaricides, pyridaben and tebufenpyrad, was detected. PBO synergism experiments, in vivo enzyme assays and gene expression analysis suggest a minor involvement of cytochrome P450 monooxygenases in fenpyroximate resistance, which is in contrast with many reported cases for the closely related Tetranychus urticae. Next, we determined the frequency of a well-known mutation in the target-site of METI-Is, the PSST subunit, associated with METI-I resistance. Indeed, the H92R substitution was detected in a highly fenpyroximate resistant P. citri population. Additionally, a new amino acid substitution at a conserved site in the PSST subunit was detected, A94V, with higher allele frequencies in a moderately resistant population. Marker-assisted back-crossing in a susceptible background confirmed the potential involvement of the newly discovered A94V mutation in fenpyroximate resistance. However, introduction of the A94V mutation in the PSST homologue of D. melanogaster using CRISPR-Cas9 did not result in fenpyroximate resistant flies. In addition, differences in binding curves between METI-Is and complex I measured directly, in isolated transgenic and wildtype mitochondria preparations, could not be found.
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•fenpyroximate resistance was investigated in seven Panonychus citri populations from Iran•fenpyroximate resistance ratios reached up to 75-fold and cross-resistance with other METI-I acaricides was observed•synergism experiments, in vivo assays and expression analysis suggest a minor role for P450s in fenpyroximate resistance•a previously reported resistance mutation, H92R in PSST of Complex I, was detected in a highly resistant population•a new mutation, A94V in PSST, was detected in a resistant population but no clear claim regarding its role could be made
We discuss the recent “realpolitik” analysis of Wisian and Traphagan (2020) of the potential geopolitical fallout of the success of the Search for Extraterrestrial Intelligence (SETI). They conclude ...that “passive” SETI involves an underexplored yet significant risk. This is the risk that, in the event of a successful, passive detection of extraterrestrial technology, state-level actors could seek to gain an information monopoly on communications with an extraterrestrial intelligence. These attempts could lead to international conflict and potentially disastrous consequences. In response to this possibility, they argue that scientists and facilities engaged in SETI should preemptively engage in significant security protocols to forestall this risk. We find several flaws in their analysis. While we do not dispute that a realpolitik response is possible, we uncover concerns with Wisian and Traphagan's presentation of the realpolitik paradigm, and we argue that sufficient reason is not given to justify treating this potential scenario as action-guiding over other candidate geopolitical responses. Furthermore, even if one assumes that a realpolitik response is the most relevant geopolitical response, we show that it is highly unlikely that a nation could successfully monopolize communication with ETI. Instead, the real threat that the authors identify is based on the perception by state actors that an information monopoly is likely. However, as we show, this perception is based on an overly narrow contact scenario. Overall, we critique Wisian and Traphagan's argument and resulting recommendations on technical, political, and ethical grounds. Ultimately, we find that not only are Wisian and Traphagan's recommendations unlikely to work, they may also precipitate the very ills that they foresee. As an alternative to the Wisian and Traphagan recommendations, we recommend transparency and data sharing (which are consistent with currently accepted best practices), further development of postdetection protocols, and better education of policymakers in this space.
Baccalaureate student nurses entering their psychiatric or mental health clinical rotation are often fearful of their upcoming experience.
To give students the opportunity to deal with some of these ...issues in a safe, nonthreatening environment, nursing faculty developed a Mental Health Simulation experience using two individual scenarios that included difficult-to-address behaviors and topics encountered in psychiatric as well as general hospital settings.
A total of 54 students participated in this quality improvement educational project. Results showed overall decreases in anxiety levels and positive responses on all items in the Medical Education Technologies, Inc., Simulation Effectiveness Tool.
Simulation experiences in the psychiatric or mental health arena, both as participants and as observers, appeared to decrease students' anxiety about their upcoming clinical rotation and enhanced their clinical understanding.
The predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) is a key natural enemy applied in phytophagous mite control in agricultural production areas. This study is aimed at ...investigating the development of pyridaben resistance as a result of the selection pressure under laboratory conditions on N. californicus mites, the inheritance of pyridaben resistance in this predatory mite, and the relationship of resistance with target region mutations. Pyridaben resistance levels were evaluated using a leaf disc spraying tower method. As a result of seven selections, 270-fold pyridaben resistance was identified in N. californicus. As a result of inheritance studies, pyridaben resistance in F1 females resulted from incomplete dominance and sex. Neoseiulus californicus was resistant to pyridaben and there was no significant difference in the monooxygenase enzyme levels in respect to the initial population. No amino acid changes were detected in the PCR evaluations of target site mutations in the pyridaben-resistant and initial populations of N. californicus. Increased pyridaben resistance in the selected population was thought to be caused by more mechanisms other than target site mutations.
My focus is on the contemporary astrobiological activity of Messaging ExtraTerrestrial Intelligence (METI). This intentional astrobiological signaling typically involves embedding digital ...communications in powerful radio signals and transmitting those signals out into the cosmos in an explicit effort to make contact with extraterrestrial others. Some who criticize METI express concern that contact with technologically advanced extraterrestrial life could be seriously harmful to Earth or humanity. One popular response to this critique of messaging is an appeal to causal impotence sometimes referred to as the ‘Barn Door’ Argument—we are already engaged in many other detectable activities not intended for cosmic communication. If the Barn Door Argument is correct, then those who engage in messaging arguably have a moral excuse. They are permitted to continue messaging because there is no point in abstaining. I develop three ways in which the claim of causal impotence in the Barn Door Argument could be understood. I evaluate each of these in turn and demonstrate that only one is appropriate to contemporary messaging. However, this interpretation does not generate the moral excuse on which the proponents of the Barn Door Argument rely; thus, the argument fails. Finally, I entertain and respond to candidate objections.
ABSTRACT
This article reflects on mourning and interspecies responsibility. Considering what Ndyuka Maroons in the Caribbean country of Suriname—historic fugitives from plantation capitalism—call ...kunu (avenging ghosts) I explore how Ndyukas attempt to secure personal and collective autonomy in an expansively relational reality where mourning is the quintessence of relatedness. Because grief impinges on Ndyuka autonomy, daily life is understood as a flawed struggle to maintain freedom from mourning. This can only be done by paying appropriate respect to others so that they do not return as vengeful spirits dedicated to the destruction of those who have harmed them and their entire families in perpetuity. This essay examines the ethics of such deeply relational notions of autonomy and ponders its implications for understanding accountability for anthropogenic extinction.
ON SA A SIKIIFI YA WANI TAKI
A sikiifi ya taki fu a fasi di Ndyuka sama e tyai fuka anga sowtu faantiwowtu de fu den meti di e kon toon libisama kunu. A e taki tu fu sani di sa pasa te libisama kii wan libi libi sani di o toon kunu, anga fa libi sama mu dini kunu fu den sa libi makandii a wan fii fasi. Te wan sama dede, da ala sama fu a famii e tyai a fuka de makandii. Te wan kunu kon a wan famii, da a sa meke a famii fu a sama di be kii en tyai a fuka de soseefi tu. Libisama ná e wani fu tyai a fuka, ma a kunu sa meke den tyai en namo namo, bika a so wan fasi a o meke den fii a seefi tyali di en famii be fii, di den kii en. Fu di kunu a wani sani di de tuu tuu, da libisama mu libi a wan lesipeki fasi fu den no mu meke kunu gi den famii di o tan fika gi den baka pikin fu pikin, paansu fu paansu. A sikiifi ya e taki tu fu a fasi di Ndyuka sama denki fu libi anga den busi sani, anga fa den mu meke mofu a makandii fu libi anga den sani di sa toon kunu, fu a no mu poti den a fuka. A sikiifi ya taki en so, bika somen sama ná e lesipeki den sowtu a sowtu meti ya, ofuso den bon, anga soseefi den peesi pe den e tan fu libi moo. A toli ya e soi taki Ndyuka sama abi fuu koni di sa leli den bakaasama fu soi den fa den mu libi a wan lesipeki fasi di o meke den ná o poli a goontapu, ma den o tan libi bun bun anga taawan.
One of the main principles of the Hippocratic oath, which has guided medical practice for 2500 years, is Primum non nocere (first, do no harm). This means, among other things, that when the stakes ...are high (a patient's life) and one has no idea what one should do, it is better to do nothing at all than risk a treatment that might make things worse. We argue for a similar approach to a face-to-face first contact scenario. In such a situation, the stakes are literally the highest imaginable (the survival of humanity, perhaps even the entire terrestrial ecosystem), and we have almost nothing to go on – we will know next to nothing about our alien interlocutors and can not rely on our evolved instincts or simplistic analogies from Earth's history to guide us appropriately. The smart approach, therefore, is one of extreme passivity and caution. In particular, we argue that an inviolate “prime directive” needs to be imposed on any crew of a mission beyond near Earth such that they will do nothing, even in self-defense, that might potentially be considered threatening. While such a passive approach will forego many opportunities, first contact should be viewed primarily as setting the stage for second contact, with the goal of establishing the alien presence and communicating our harmlessness – no more. In the grand scheme of things, even the loss of the human crew is a small price to pay for the safety of the Earth and all its inhabitants.
In the vigorous academic debate over the risks of the Search for ExtraTerrestrial Intelligence (SETI) and active Messaging ExtraTerrestrial Intelligence (ETI) (METI), a significant factor has been ...largely overlooked. Specifically, the risk of merely detecting an alien signal from passive SETI activity is usually considered to be negligible. The history of international relations viewed through the lens of the realpolitik tradition of realist political thought suggests, however, that there is a measurable risk of conflict over the perceived benefit of monopoly access to ETI communication channels. This possibility needs to be considered when analyzing the potential risks and benefits of contact with ETI.
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