necessary and sufficient
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2022 ◽  
Vol 12 (2) ◽  
pp. 883
Author(s):  
Yuxin Cui ◽  
Shu Li ◽  
Yunxiao Shan ◽  
Fengqiu Liu

This study focuses on the finite-time set reachability of probabilistic Boolean multiplex control networks (PBMCNs). Firstly, based on the state transfer graph (STG) reconstruction technique, the PBMCNs are extended to random logic dynamical systems. Then, a necessary and sufficient condition for the finite-time set reachability of PBMCNs is obtained. Finally, the obtained results are effectively illustrated by an example.


Symmetry ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 163
Author(s):  
Karl Hess

This review is related to the Einstein-Bohr debate and to Einstein–Podolsky–Rosen’s (EPR) and Bohm’s (EPRB) Gedanken-experiments as well as their realization in actual experiments. I examine a significant number of papers, from my minority point of view and conclude that the well-known theorems of Bell and Clauser, Horne, Shimony and Holt (CHSH) deal with mathematical abstractions that have only a tenuous relation to quantum theory and the actual EPRB experiments. It is also shown that, therefore, Bell-CHSH cannot be used to assess the nature of quantum entanglement, nor can physical features of entanglement be used to prove Bell-CHSH. Their proofs are, among other factors, based on a statistical sampling argument that is invalid for general physical entities and processes and only applicable for finite “populations”; not for elements of physical reality that are linked, for example, to a time-like continuum. Bell-CHSH have, furthermore, neglected the subtleties of the theorem of Vorob’ev that includes their theorems as special cases. Vorob’ev found that certain combinatorial-topological cyclicities of classical random variables form a necessary and sufficient condition for the constraints that are now known as Bell-CHSH inequalities. These constraints, however, must not be linked to the observables of quantum theory nor to the actual EPRB experiments for a variety of reasons, including the existence of continuum-related variables and appropriate considerations of symmetry.


Mathematics ◽  
2022 ◽  
Vol 10 (2) ◽  
pp. 247
Author(s):  
Kai An Sim ◽  
Kok Bin Wong

By recalling van der Waerden theorem, there exists a least a positive integer w=w(k;r) such that for any n≥w, every r-colouring of [1,n] admits a monochromatic k-term arithmetic progression. Let k≥2 and rk(n) denote the minimum number of colour required so that there exists a rk(n)-colouring of [1,n] that avoids any monochromatic k-term arithmetic progression. In this paper, we give necessary and sufficient conditions for rk(n+1)=rk(n). We also show that rk(n)=2 for all k≤n≤2(k−1)2 and give an upper bound for rp(pm) for any prime p≥3 and integer m≥2.


2022 ◽  
Author(s):  
Satoru Iwasaki

Abstract This paper deals with initial state estimation problems of the heat equation in equilateral metric graphs being admitted to have cycles. Particularly, we are concerned with suitable placements of observation points in order to uniquely determine the initial state from observation data. We give a necessary and sufficient condition for suitable placements of observation points, and such suitable placements are determined from transition matrices of metric graphs. From numerical simulations, we confirm effectiveness of a necessary and sufficient condition.


2022 ◽  
Author(s):  
Anthony E Postliglione ◽  
Gloria K Muday

Stomatal closure regulates transpiration and gas exchange in response to environmental cues. Drought upregulates ABA signaling, which elevates levels of reactive oxygen species (ROS). However, the subcellular location and identity of these ROS has received limited study. We found that in guard cells, ABA increased fluorescence of the general redox sensor, dichlorofluorescein (DCF), in distinct subcellular locations including chloroplasts, cytosol, nuclei, and cytosolic puncta. These changes were lost in ABA-insensitive quintuple receptor mutant and accentuated in an ABA-hypersensitive mutant. ABA induced ROS accumulation in these subcellular compartments was lost in mutants with defects in genes encoding hydrogen peroxide synthesizing respiratory burst oxidase homolog (RBOH) enzymes and guard cells treated with the RBOH inhibitor VAS2870, while exogenous hydrogen peroxide treatment is sufficient to close guard cells. The hydrogen peroxide-selective probe, peroxy orange1, also showed ABA-dependent increases in chloroplasts and cytosolic puncta. Using the more sensitive genetically-encoded hydrogen peroxide reporter roGFP-Orp1, we also detected significant hydrogen peroxide increases in the cytosol and nucleus. These cytosolic puncta accumulate ROS after ABA treatment show colocalization with Mitotracker and with a mitochondrial targeted mt-roGFP2-Orp1, which also revealed ABA-increased ROS in mitochondria. These results indicate that elevated hydrogen peroxide after ABA treatment in these subcellular compartments is necessary and sufficient to drive stomatal closure.


2022 ◽  
Vol 119 (3) ◽  
pp. e2116623119
Author(s):  
Chen Hao ◽  
Yanzhi Yang ◽  
Jianmei Du ◽  
Xing Wang Deng ◽  
Lei Li

Leaf senescence is a critical process in plants and has a direct impact on many important agronomic traits. Despite decades of research on senescence-altered mutants via forward genetics and functional assessment of senescence-associated genes (SAGs) via reverse genetics, the senescence signal and the molecular mechanism that perceives and transduces the signal remain elusive. Here, using dark-induced senescence (DIS) of Arabidopsis leaf as the experimental system, we show that exogenous copper induces the senescence syndrome and transcriptomic changes in light-grown plants parallel to those in DIS. By profiling the transcriptomes and tracking the subcellular copper distribution, we found that reciprocal regulation of plastocyanin, the thylakoid lumen mobile electron carrier in the Z scheme of photosynthetic electron transport, and SAG14 and plantacyanin (PCY), a pair of interacting small blue copper proteins located on the endomembrane, is a common thread in different leaf senescence scenarios, including DIS. Genetic and molecular experiments confirmed that the PCY-SAG14 module is necessary and sufficient for promoting DIS. We also found that the PCY-SAG14 module is repressed by a conserved microRNA, miR408, which in turn is repressed by phytochrome interacting factor 3/4/5 (PIF3/4/5), the key trio of transcription factors promoting DIS. Together, these findings indicate that intracellular copper redistribution mediated by PCY-SAG14 has a regulatory role in DIS. Further deciphering the copper homeostasis mechanism and its interaction with other senescence-regulating pathways should provide insights into our understanding of the fundamental question of how plants age.


2022 ◽  
Author(s):  
Polymnia Georgiou ◽  
Panos Zanos ◽  
Ta-Chung M Mou ◽  
Xiaoxian An ◽  
Danielle M Gerhard ◽  
...  

Differential rodent responses to the sex of human experimenters could have far reaching consequences in preclinical studies. Here, we show that the sex of human experimenters affects mouse behaviours and responses to the rapid-acting antidepressant ketamine and its bioactive metabolite (2R,6R)-hydroxynorketamine. We found that mice manifest aversion to human male odours, preference to female odours, and increased susceptibility to stress when handled by male experimenters. This male induced aversion and stress susceptibility is mediated by the activation of brain corticotropin-releasing factor (CRF) neurons projecting from the entorhinal cortrex to hippocampal area CA1. We further establish that exposure to male scent prior to ketamine administration activates CRF neurons projecting from the entorhinal cortex to hippocampus, and that CRF is necessary and sufficient for the in vivo and in vitro actions of ketamine. Further understanding of the specific and quantitative contributions of the sex of human experimenters to different experimental outcomes in rodents may lead not only to reduced heterogeneity between studies, but also increased capability to uncover novel biological mechanisms.


2022 ◽  
Vol 14 (2) ◽  
pp. 780
Author(s):  
Yovana Clarivel Surco-Guillen ◽  
Javier Romero ◽  
Rocío Rodríguez-Rivero ◽  
Isabel Ortiz-Marcos

From the reports of the Inter-American Development Bank (IDB) Office of Evaluation and Oversight (OVE), a limited analysis of the factors affecting the execution of development cooperation projects was identified. Thanks to the review of scientific articles by renowned authors, effectiveness, relevance, competencies and motivation, sustainability, risk management, and additionality were evaluated using the analysis of relationships between variables and causality using IBM SPSS and fsQCA 3.0 software, respectively. As a result, a model was obtained that relates the components, factors, and roles that make up the stakeholder matrix. It was concluded that the effectiveness factor has a significant relationship with the success of a project; however, this could not be possible without a good development of sustainability and risk management, the latter being a necessary and sufficient condition for success in this type of projects. Currently, risk management has not only become a necessity nowadays, but the improvement of risk management will increase sustainability in project management, the main factors for the success of a project.


2022 ◽  
Author(s):  
Leonardo M Cardozo ◽  
Blythe C Dillingham ◽  
Andre F Sousa ◽  
Westley Dang ◽  
Nicholas Job ◽  
...  

The nature and distribution of the synaptic changes that underlie memory are not well understood. We examined the synaptic plasticity behind context fear learning and found that conditioning produced potentiation of excitatory synapses specifically onto the basolateral amygdala neurons activated during learning. This synaptic potentiation lasted at least 7 days, and its disruption impaired memory recall. High frequency optogenetic stimulation of the CS and US-activated ensembles or biochemical induction of synaptic potentiation in US-responsive neurons alone was sufficient to produce a context fear association without prior associative training. These results suggest that plasticity of CS inputs onto US-responsive amygdala neurons is a necessary and sufficient step in forming context fear associations, and that context discrimination is determined by the CS-specific amygdala inputs activated during retrieval.


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