ABSTRACT During a period of three days beginning 2013 January 17, twelve recurrent reconnection events occur within a small region of opposing flux embedded within one footpoint of an active region, ...accompanied by flares and jets observed in EUV and fast and faint structureless "puffs" observed by coronagraphs. During the same period a slow structured CME gradually erupts, with one end anchored close to, or within, the jetting region. Four of the jet events occur in pairs-a narrow, primary jet followed within a few tens of minutes by a wider, more massive, jet. All the jets are slow, with an apparent speed of ∼100 km s−1. The speed of the wide puffs in the coronagraph data is ∼300 km s−1, and the timing of their appearance rules out a direct association with the EUV jetting material. The jet material propagates along large-scale closed-field loops and does not escape to the extended corona. The rapid reconfiguration of the closed loops following reconnection causes an outwardly propagating disturbance, or wave front, which manifests as puffs in coronagraph data. Furthermore, the newly expanded closed flux tube forms a pressure imbalance, which can result in a secondary jet. The reconnection events, through recurrent field reconfiguration, also leads to the gradual eruption of the structured flux tube appearing as the slow CME. Faint propagating coronal disturbances resulting from flares/jets may be common, but are usually obscured by associated ejections. Occasionally, the associated material ejections are absent, and coronal puffs may be clearly observed.
Purpose The purpose of this study was to evaluate the effect of graft size on patient-reported outcomes and revision risk after anterior cruciate ligament (ACL) reconstruction. Methods A ...retrospective chart review of prospectively collected cohort data was performed, and 263 of 320 consecutive patients (82.2%) undergoing primary ACL reconstruction with hamstring autograft were evaluated. We recorded graft size; femoral tunnel drilling technique; patient age, sex, and body mass index at the time of ACL reconstruction; Knee Injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee score preoperatively and at 2 years postoperatively; and whether each patient underwent revision ACL reconstruction during the 2-year follow-up period. Revision was used as a marker for graft failure. The relation between graft size and patient-reported outcomes was determined by multiple linear regression. The relation between graft size and risk of revision was determined by dichotomizing graft size at 8 mm and stratifying by age. Results After we controlled for age, sex, operative side, surgeon, body mass index, graft choice, and femoral tunnel drilling technique, a 1-mm increase in graft size was noted to correlate with a 3.3-point increase in the KOOS pain subscale ( P = .003), a 2.0-point increase in the KOOS activities of daily living subscale ( P = .034), a 5.2-point increase in the KOOS sport/recreation function subscale ( P = .004), and a 3.4-point increase in the subjective International Knee Documentation Committee score ( P = .026). Revision was required in 0 of 64 patients (0.0%) with grafts greater than 8 mm in diameter and 14 of 199 patients (7.0%) with grafts 8 mm in diameter or smaller ( P = .037). Among patients aged 18 years or younger, revision was required in 0 of 14 patients (0.0%) with grafts greater than 8 mm in diameter and 13 of 71 patients (18.3%) with grafts 8 mm in diameter or smaller. Conclusions Smaller hamstring autograft size is a predictor of poorer KOOS sport/recreation function 2 years after primary ACL reconstruction. A larger sample size is required to confirm the relation between graft size and risk of revision ACL reconstruction. Level of Evidence Level III, retrospective comparative study.
At present, there are few technologies which enable the detection, identification and viability analysis of protozoan pathogens including Cryptosporidium and/or Giardia at the single (oo)cyst level. ...We report the use of Microfluidic Impedance Cytometry (MIC) to characterise the AC electrical (impedance) properties of single parasites and demonstrate rapid discrimination based on viability and species. Specifically, MIC was used to identify live and inactive C. parvum oocysts with over 90% certainty, whilst also detecting damaged and/or excysted oocysts. Furthermore, discrimination of Cryptosporidium parvum, Cryptosporidium muris and Giardia lamblia, with over 92% certainty was achieved. Enumeration and identification of (oo)cysts can be achieved in a few minutes, which offers a reduction in identification time and labour demands when compared to existing detection methods.
Despite a reduction of Salmonella contamination on final poultry products, the level of human salmonellosis cases attributed to poultry has remained unchanged over the last few years. There needs to ...be improved effort to target serovars which may survive antimicrobial interventions and cause illness, as well as to focus on lessening the amount of contamination entering the processing plant. Advances in molecular enumeration approaches allow for the rapid detection and quantification of Salmonella in pre- and postharvest samples, which can be combined with deep serotyping to properly assess the risk affiliated with a poultry flock. In this study, we collected a total of 160 boot sock samples from 20 broiler farms across four different integrators with different antibiotic management programs. Overall, Salmonella was found in 85% (68/80) of the houses, with each farm having at least one Salmonella-positive house. The average Salmonella quantity across all four complexes was 3.6 log
CFU/sample. Eleven different serovars were identified through deep serotyping, including all three key performance indicators (KPIs; serovars Enteritidis, Infantis, and Typhimurium) defined by the U.S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS). There were eight multidrug resistant isolates identified in this study, and seven which were serovar Infantis. We generated risk scores for each flock based on the presence or absence of KPIs, the relative abundance of each serovar as calculated with CRISPR-SeroSeq (
typing by
uencing the
lustered
egularly
nterspaced
alindromic
epeats), and the quantity of Salmonella organisms detected. The work presented here provides a framework to develop directed processing approaches and highlights the limitations of conventional Salmonella sampling and culturing methods.
Nearly one in five foodborne Salmonella illnesses are derived from chicken, making it the largest single food category to cause salmonellosis and indicating a need for effective pathogen mitigation. Although industry has successfully reduced Salmonella incidence in poultry products, there has not been a concurrent reduction in human salmonellosis linked to chicken consumption. New efforts are focused on improved control at preharvest, which requires improved Salmonella surveillance. Here, we present a high-resolution surveillance approach that combines quantity and identity of Salmonella in broiler flocks prior to processing which will further support improved Salmonella controls in poultry. We developed a framework for this approach, indicating that it is possible and important to harness deep serotyping and molecular enumeration to inform on-farm management practices and to minimize risk of cross-contamination between flocks at processing. Additionally, this framework could be adapted to Salmonella surveillance in other food animal production systems.
Orexin (hypocretin) and addiction Mehr, Jacqueline B.; Bilotti, Michelle M.; James, Morgan H.
Trends in neurosciences,
11/2021, Letnik:
44, Številka:
11
Journal Article
Recenzirano
Odprti dostop
Although originally implicated in appetite and sleep/wakefulness, the hypothalamic orexin (hypocretin) system has now been demonstrably linked with motivated behavior. This highly plastic system ...responds to reward-associated environmental stimuli and becomes pathologically overactive in addicted states. Here, we provide a brief overview of the roles of the orexin system in reward-seeking and addiction, as well as potential therapeutic opportunities for substance use disorders based on normalizing orexin function.
Display omitted
•Orexin-1 receptor antagonists hold great promise for treatment of drug addiction.•These compounds are thought to reduce motivation for drug seeking.•Less is known about effects of ...orexin-1 receptor blockade on cognitive functioning.•We tested the orexin-1 receptor antagonist SB-334867 in a rat stop signal task.•SB-334867 reduced task motivation but had little effect on executive control (response inhibition).
There is considerable clinical interest in the neuropeptide orexin/hypocretin for its ability to regulate motivation and reward as well as arousal and wakefulness. For instance, antagonists for the orexin-1 receptor (OxR1) are thought to hold great promise for treating drug addiction and disorders associated with overeating, as these compounds repeatedly have been found to suppress seeking of various drugs of abuse as well as highly palatable foods in preclinical models. Given the hypothesized role of OxR1 signaling in cue-driven motivation, an outstanding question is whether pharmacologically blocking this receptor affects cognitive functioning. Response inhibition – the ability to cancel ongoing behavior – is one aspect of cognitive control that may be particularly relevant. Response inhibition deficits are commonly associated with a range of psychiatric disorders and neurological diseases, including substance use disorders and obesity. Moreover, OxR1 signaling recently has been implicated in waiting impulsivity, another aspect of inhibitory control. Here, we investigated the effects of the OxR1 antagonist SB-334867 on response inhibition in a rat version of the stop-signal reaction time task. Results show that acutely blocking OxR1 had minimal effects on response inhibition or attentional functioning. In contrast, this manipulation reduced motivation to perform the task and earn food rewards, consistent with other recent findings. These results add to the growing body of literature implicating OxR1 in the regulation of motivation and suggest that effects of pharmacological compounds such as SB-334867 on drug-seeking behavior are not related to effects on response inhibition.
Visible absorbance spectroscopy is a widely used tool in chemical, biochemical, and medical laboratories. The theory and methods of absorbance spectroscopy are typically introduced in upper division ...undergraduate chemistry courses, but could be introduced earlier with the right curriculum and instrumentation. A major challenge in teaching spectroscopy is gaining access to laboratory equipment, which can be expensive. Even common educational spectrophotometers still carry a substantial cost and have the disadvantage of being inherently closed designs. We report on a 3D-printable smartphone spectrophotometer that is very inexpensive to build, yet retains the functionality and analytical accuracy necessary to teach concepts like the Beer–Lambert Law. The optical components are arranged in an intuitive, accessible way so that students can see each relevant part and experiment with the parameters. Here, we describe the device and provide exercises to teach different concepts in analytical spectrophotometry.
It has been proposed that binge eating reflects a pathological compulsion driven by the "addictive" properties of foods. Proponents of this argument highlight the large degree of phenomenological and ...diagnostic overlap between binge eating disorder (BED) and substance use disorders (SUDs), including loss of control over how much is consumed and repeated unsuccessful attempts to abstain from consumption, as well as commonalities in brain structures involved in food and drug craving. To date, very little attention has been given to an additional behavioral symptom that BED shares with SUDs-sleep dysregulation-and the extent to which this may contribute to the pathophysiology of BED. Here, we review studies examining sleep outcomes in patients with BED, which collectively point to a heightened incidence of sleep abnormalities in BED. We identify the orexin (hypocretin) system as a potential neurobiological link between compulsive eating and sleep dysregulation in BED, and provide a comprehensive update on the evidence linking this system to these processes. Finally, drawing on evidence from the SUD literature indicating that the orexin system exhibits significant plasticity in response to drugs of abuse, we hypothesize that chronic palatable food consumption likewise increases orexin system activity, resulting in dysregulated sleep/wake patterns. Poor sleep, in turn, is predicted to exacerbate binge eating, contributing to a cycle of uncontrolled food consumption. By extension, we suggest that pharmacotherapies normalizing orexin signaling, which are currently being trialed for the treatment of SUDs, might also have utility in the clinical management of BED.
•We studied persistent effects of the orexin-1 receptor antagonist SB-334867 on opioid motivation.•Systemic injections of SB reduced motivation for remifentanil 24 h after ...administration.•Intra-pallidal SB reduced motivation for remifentanil up to 72 h after administration.•Effects of SB on opioid seeking behavior persist beyond the bioavailability of the compound.
The orexin (hypocretin) system is multifaceted, and regulates sleep-wake cycles, nociception, endocrine function and reward-seeking behavior. We have established an important role for this system in motivation for drugs of abuse. The orexin-1 receptor (Ox1R) antagonist SB334867 (SB) reduces seeking of drug reward under conditions of high motivation. There is some evidence that the effects of systemic SB on reward seeking persist beyond the pharmacological availability of the drug, however the time course of these effects is not well characterized, nor is it known whether similar persistent effects are observed following intraparenchymal injections. Here, we used a behavioral economics paradigm, which allows for repeated testing of drug motivation across consecutive days, to examine the persistent effects of acute systemic and local treatment with SB on motivation for the short-acting μ‐opioid receptor agonistremifentanil. Systemic injections of SB immediately prior to behavioral testing reduced motivation for remifentanil; this effect was sustained on a subsequent test at 24 h, but not on a third test at 48 h. When injected into ventral pallidum (VP) the effects of SB were more persistent, with reduced motivation observed for up to 48 h. We next made SB injections into VP 24 h prior to behavioral testing; this produced effects that persisted for at least 72 h post-treatment. Cued reinstatement of extinguished remifentanil seeking was also attenuated by pretreatment with SB 24 h earlier. These data indicate that the effects of SB on opioid seeking behavior persist beyond the bioavailability of the compound. These observations have important ramifications for the future clinical use of orexin receptor antagonists for the treatment of addiction.
Bonding interactions and spin-orbit coupling in the topological insulator SrAg
Sb
are investigated using DFT with orbital projection analysis. Ag-Ag delta bonding is a key ingredient in the ...topological insulating state because the
delta antibonding band forms a band inversion with the 5 s sigma bonding band. Spin-orbit coupling is required to lift d orbital degeneracies and lower the antibonding band enough to create the band inversion. These bonding effects are enabled by a longer-than-covalent Ag-Ag distance in the crystal lattice, which might be a structural characteristic of other transition metal based topological insulators. A simplified model of the topological bands is constructed to capture the essence of the topological insulating state in a way that may be engineered in other materials.
PDF
