Full-commanding a network: The dictator

A network of chaotic dynamical systems may synchronize. For some networks there is the possibility that, coupling a new node to the network, the synchronization will be commanded by that new node. That possibility depends on the network and on the way the new node is coupled to the network.We consider a coupling that can provide what we call a full-commanding and we define the corresponding full-commandwindow. The limit situations corresponding to a completely connected network and to a completely disconnected one provide us some understanding about what makes a network more receptive or more resistant to commanding

Discerning the role of polymicrobial biofilms in the ascent, prevalence, and extent of heteroresistance in clinical practice

Antimicrobial therapy is facing a worrisome and underappreciated challenge, the phenomenon of heteroresistance (HR). HR has been gradually documented in clinically relevant pathogens (e.g. Pseudomonas aeruginosa, Staphylococcus aureus, Burkholderia spp., Acinetobacter baumannii, Klebsiella pneumoniae, Candida spp.) towards several drugs and is believed to complicate the clinical picture of chronic infections. This type of infections are typically mediated by polymicrobial biofilms, wherein microorganisms inherently display a wide range of physiological states, distinct metabolic pathways, diverging refractory levels of stress responses, and a complex network of chemical signals exchange. This review aims to provide an overview on the relevance, prevalence, and implications of HR in clinical settings. Firstly, related terminologies (e.g. resistance, tolerance, persistence), sometimes misunderstood and overlapped, were clarified. Factors generating misleading HR definitions were also uncovered. Secondly, the recent HR incidences reported in clinically relevant pathogens towards different antimicrobials were annotated. The potential mechanisms underlying such occurrences were further elucidated. Finally, the link between HR and biofilms was discussed. The focus was to recognize the presence of heterogeneous levels of resistance within most biofilms, as well as the relevance of polymicrobial biofilms in chronic infectious diseases and their role in resistance spreading. These topics were subject of a critical appraisal, gaining insights into the ascending clinical implications of HR in antimicrobial resistance spreading, which could ultimately help designing effective therapeutic options.This work was supported by the Portuguese Foundation for Science Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2020 unit BioTecNorte operation [NORTE-01-0145-FEDER-000004] funded by the European Regional Development Fund under the scope of Norte2020–Programa Operacional Regional do Norte. The authors also acknowledge COMPETE2020 FCT for the project POCI-01-0145-FEDER-029,841 and for the Scientific Employment Stimulus 2017 grant [CEECIND/01507/2017] (A. M. Sousa).info:eu-repo/semantics/publishedVersio

A New Class of Four-Dimensional N=1 Supergravity with Non-minimal Derivative Couplings

In the N=1 four-dimensional new-minimal supergravity framework, we supersymmetrise the coupling of the scalar kinetic term to the Einstein tensor. This coupling, although introduces a non-minimal derivative interaction of curvature to matter, it does not introduce harmful higher-derivatives. For this construction, we employ off-shell chiral and real linear multiplets. Physical scalars are accommodated in the chiral multiplet whereas curvature resides in a linear one.Comment: 18 pages, version published at JHE

Projected WIMP sensitivity of the LUX-ZEPLIN dark matter experiment

LUX-ZEPLIN (LZ) is a next-generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. Using a two-phase xenon detector with an active mass of 7 tonnes, LZ will search primarily for low-energy interactions with weakly interacting massive particles (WIMPs), which are hypothesized to make up the dark matter in our galactic halo. In this paper, the projected WIMP sensitivity of LZ is presented based on the latest background estimates and simulations of the detector. For a 1000 live day run using a 5.6-tonne fiducial mass, LZ is projected to exclude at 90% confidence level spin-independent WIMP-nucleon cross sections above 1.4×10-48 cm2 for a 40 GeV/c2 mass WIMP. Additionally, a 5σ discovery potential is projected, reaching cross sections below the exclusion limits of recent experiments. For spin-dependent WIMP-neutron(-proton) scattering, a sensitivity of 2.3×10-43 cm2 (7.1×10-42 cm2) for a 40 GeV/c2 mass WIMP is expected. With underground installation well underway, LZ is on track for commissioning at SURF in 2020

A CLINICAL STUDY OF INHALANT ANAESTHESIA IN DOGS

A clinical trial was undertaken using three different inhalant anaesthetic agents and one intravenous anaesthetic agent in dogs undergoing routine desexing surgery. Healthy adult dogs undergoing either ovariohysterectomy or castration were assessed as to their demeanour, with the more excitable dogs being placed in groups receiving premedication with acepromazine and morphine. All dogs were then randomly assigned an anaesthetic agent for induction of general anaesthesia. The agents were the inhalants halothane, isoflurane and sevoflurane, and the intravenous agent propofol. Inhalant inductions were undertaken using a tight fitting mask attached to a standard anaesthetic machine with a rebreathing circuit, with the maximum dose of inhalant available from a standard vaporiser. Propofol inductions were undertaken via intravenous catheter. Dogs induced with propofol were randomly assigned one of the three inhalant agents for maintenance. Those induced by inhalant agent were maintained using the same agent. The surgical procedure was undertaken in standard fashion, as was recovery from anaesthesia. All dogs received the non-steroidal anti-inflammatory agent meloxicam. Data collection was divided into three stages: induction, maintenance, and recovery from anaesthesia. Variables measured at induction of anaesthesia were time to intubation, number of intubation attempts, tolerance of mask, quality of induction and quality of transfer to the maintenance stage. Standard variables for monitoring of anaesthesia were recorded throughout the maintenance of anaesthesia. Variables measured at recovery were time to righting, time to standing and quality of recovery. The mean time to intubation when using the newer inhalant sevoflurane (196.2 ± 14.8sec, mean ± SE) was not significantly different to that for halothane (221.4 ± 14.0sec) or isoflurane (172.4 ± 15.0sec). Time to intubation with isoflurane was significantly faster than with halothane. Mean time to intubation with propofol (85.4 ± 7.7sec) was significantly faster than that for any of the three inhalants. Choice of inhalant had no effect on quality of induction. The use of premedication significantly improved the quality of induction. The use of propofol for induction likewise significantly improved the quality of induction. Standard cardiorespiratory variables measured during the maintenance phase of anaesthesia remained within normal clinical ranges for all three inhalants, and were therefore not further analysed. Choice of inhalant agent had no significant effect on the time to righting or standing in recovery. The use of propofol for induction had no effect on these variables. Animals placed in groups receiving premedication had significantly longer times to righting and standing. The oesophageal temperature at the end of the procedure had a significant effect on times to righting and standing, with lower temperatures contributing to slower recoveries. Independent of procedure time, male dogs had shorter times to righting than female dogs

Projected sensitivity of the LUX-ZEPLIN experiment to the 0νββ decay of Xe 136

The LUX-ZEPLIN (LZ) experiment will enable a neutrinoless double β decay search in parallel to the main science goal of discovering dark matter particle interactions. We report the expected LZ sensitivity to Xe136 neutrinoless double β decay, taking advantage of the significant (>600 kg) Xe136 mass contained within the active volume of LZ without isotopic enrichment. After 1000 live-days, the median exclusion sensitivity to the half-life of Xe136 is projected to be 1.06×1026 years (90% confidence level), similar to existing constraints. We also report the expected sensitivity of a possible subsequent dedicated exposure using 90% enrichment with Xe136 at 1.06×1027 years

Deconstructing the DGAT1 enzyme: membrane interactions at substrate binding sites

Diacylglycerol acyltransferase 1 (DGAT1) is a key enzyme in the triacylglyceride synthesis pathway. Bovine DGAT1 is an endoplasmic reticulum membrane-bound protein associated with the regulation of fat content in milk and meat. The aim of this study was to evaluate the interaction of DGAT1 peptides corresponding to putative substrate binding sites with different types of model membranes. Whilst these peptides are predicted to be located in an extramembranous loop of the membrane-bound protein, their hydrophobic substrates are membrane-bound molecules. In this study, peptides corresponding to the binding sites of the two substrates involved in the reaction were examined in the presence of model membranes in order to probe potential interactions between them that might influence the subsequent binding of the substrates. Whilst the conformation of one of the peptides changed upon binding several types of micelles regardless of their surface charge, suggesting binding to hydrophobic domains, the other peptide bound strongly to negatively-charged model membranes. This binding was accompanied by a change in conformation, and produced leakage of the liposome-entrapped dye calcein. The different hydrophobic and electrostatic interactions observed suggest the peptides may be involved in the interactions of the enzyme with membrane surfaces, facilitating access of the catalytic histidine to the triacylglycerol substrates

Recruitment of pre-dementia participants: main enrollment barriers in a longitudinal amyloid-PET study

Background: The mismatch between the limited availability versus the high demand of participants who are in the pre-dementia phase of Alzheimer’s disease (AD) is a bottleneck for clinical studies in AD. Nevertheless, potential enrollment barriers in the pre-dementia population are relatively under-reported. In a large European longitudinal biomarker study (the AMYPAD-PNHS), we investigated main enrollment barriers in individuals with no or mild symptoms recruited from research and clinical parent cohorts (PCs) of ongoing observational studies. Methods: Logistic regression was used to predict study refusal based on sex, age, education, global cognition (MMSE), family history of dementia, and number of prior study visits. Study refusal rates and categorized enrollment barriers were compared between PCs using chi-squared tests. Results: 535/1856 (28.8%) of the participants recruited from ongoing studies declined participation in the AMYPAD-PNHS. Only for participants recruited from clinical PCs (n = 243), a higher MMSE-score (β = − 0.22, OR = 0.80, p <.05), more prior study visits (β = − 0.93, OR = 0.40, p <.001), and positive family history of dementia (β = 2.08, OR = 8.02, p <.01) resulted in lower odds on study refusal. General study burden was the main enrollment barrier (36.1%), followed by amyloid-PET related burden (PCresearch = 27.4%, PCclinical = 9.0%, X 2 = 10.56, p =.001), and loss of research interest (PCclinical = 46.3%, PCresearch = 16.5%, X 2 = 32.34, p <.001). Conclusions: The enrollment rate for the AMYPAD-PNHS was relatively high, suggesting an advantage of recruitment via ongoing studies. In this observational cohort, study burden reduction and tailored strategies may potentially improve participant enrollment into trial readiness cohorts such as for phase-3 early anti-amyloid intervention trials. The AMYPAD-PNHS (EudraCT: 2018–002277-22) was approved by the ethical review board of the VU Medical Center (VUmc) as the Sponsor site and in every affiliated site

Effects of bromopride on the healing of left colon anastomoses of rats

Objetivo: Avaliar os efeitos da bromoprida sobre a formação de aderências e a cicatrização de anastomoses de cólon esquerdo de ratos. Métodos: Foram incluídos 40 ratos, divididos em dois grupos contendo 20 animais, para administração de bromoprida (grupo de estudo- E) ou solução fisiológica (grupo controle- C). Cada grupo foi dividido em subgrupos contendo 10 animais cada, para eutanásia no terceiro (E3 e C3) ou no sétimo dia (E7 e C7) de pós-operatório. Os ratos foram submetidos à secção do cólon esquerdo e anastomose término-terminal. No dia da relaparotomia, foi avaliada a quantidade total de aderências e removido um segmento colônico contendo a anastomose para análise histopatológica, da força de ruptura e da concentração de hidroxiprolina. Resultados: Não houve diferença entre os grupos em relação à evolução clínica. Dois animais do grupo de estudo apresentaram deiscência de anastomose bloqueada. Os animais que receberam bromoprida apresentaram número de aderências intracavitárias e aderências à anastomose semelhantes ao grupo controle. As anastomoses dos animais do grupo E3 apresentaram menor resistência de ruptura do que as do grupo C3 (p=0,04). Este efeito não ocorreu no sétimo dia de pós-operatório (p=0,37). Não houve diferença significativa entre os grupos em relação à histopatologia ou concentração de hidroxiprolina das anastomoses. Conclusão: O uso da bromoprida está associado à diminuição da resistência tênsil de anastomoses do cólon esquerdo de ratos no terceiro dia de pós-operatório.Objective: To evaluate the effects of bromopride on the formation of adhesions and anastomotic healing in the left colon of rats. Methods: We divided 40 rats into two groups of 20 animals, administration of bromopride (study group-E) or saline (control group- C). Each group was divided into subgroups containing 10 animals each for euthanasia in the third (C3 and E3) or the seventh (E7 and C7) postoperative days. The rats were submitted to section of the left colon and end-to-end anastomosis. On the day of reoperation, we evaluated the total amount of adhesions and removed a colonic segment containing the anastomosis for histopathological analysis, assessment of rupture strength and hydroxyproline concentration. Results: There was no difference between groups in relation to clinical outcome. Two animals in the study group had blocked anastomotic leakage. The animals that received bromopride had the number of intracavitary adhesions and adhesions to the anastomosis similar to the control group. The anastomoses from the group E3 animals showed lower resistance to rupture the one from the C3 group (p = 0.04). This effect did not occur on the seventh postoperative day (p = 0.37). There was no significant difference between groups in relation to histopathology and hydroxyproline concentration in the anastomoses. Conclusion: The use of bromopride was associated with decreased tensile strength of left colon anastomosis in rats in the third postoperative day