Plasma and wave measurements from the NASA Magnetospheric Multiscale mission are presented for magnetotail reconnection events on 3 July and 11 July 2017. Linear dispersion analyses were performed ...using distribution functions comprising up to six drifting bi‐Maxwellian distributions. In both events electron crescent‐shaped distributions are shown to be responsible for upper hybrid waves near the X‐line. In an adjacent location within the 3 July event a monodirectional field‐aligned electron beam drove parallel‐propagating beam‐mode waves. In the 11 July event an electron distribution consisting of a drifting core and two crescents was shown to generate upper‐hybrid and beam‐mode waves at three different frequencies, explaining the observed broadband waves. Multiple harmonics of the upper hybrid waves were observed but cannot be explained by the linear dispersion analysis since they result from nonlinear beam interactions.
Plain Language Summary
Magnetic reconnection is a process that occurs throughout the universe in ionized gases (plasmas) containing embedded magnetic fields. This process converts magnetic energy to electron and ion energy, causing phenomena such as solar flares and auroras. The NASA Magnetospheric Multiscale mission has shown that in magnetic reconnection regions there are intense electric field oscillations or waves and that electrons form crescent and beam‐like populations propagating both along and perpendicular to the magnetic field. This study shows that the observed electron populations are responsible for high‐frequency waves including their propagation directions and frequency ranges.
Key Points
Electron crescent‐shaped distributions produce upper hybrid waves in magnetotail reconnection events
Field‐aligned electron beams generate parallel electrostatic waves through the beam‐mode
Multiple crescent and convecting core distributions act together to produce broad frequency spectra as observed by MMS
Purpose>This article investigates some ongoing issues faced by higher education institutions (HEIs) having to rapidly move their teaching online during the early stages of the coronavirus (COVID-19) ...pandemic.Design/methodology/approach>The article incorporates a review of academic and policy literature concerning digitalisation and online learning in universities and qualitative interviews with staff involved in online teaching and learning at a university in Scotland.Findings>For most HEIs and organisations across the globe, the COVID-19 pandemic has accelerated the speed at which digitalisation and digital ways of working have been embedded in organisational life and service delivery including new ways of learning and working. This has led to a recognition of the need for practically focused, effective inclusive digital interventions. A range of initiatives that have been developed or accelerated in response to the pandemic are discussed. These should be explicitly designed and implemented to also reach individuals from disadvantaged backgrounds, including those with low-skill levels or qualifications and older age groups. Effort is also needed by policymakers and HEIs to better understand the challenges and unintended consequences that digital learning and working poses.Research limitations/implications>More research is needed into the methods and implications of increased online teaching. The range of interviewees is limited to one main organisation. A wider range of staff, students, HEIs and other types of organisation would add additional insights.Practical implications>Insights from interviews highlight a number of institutional responses to digitalisation, which were accelerated by the COVID-19 pandemic. These identify learning and reflection points for HEIs moving to enhanced online teaching provision.Originality/value>This article provides an analysis of the processes, issues and impacts associated with the rapid shift to digitisation in HEIs at a point in time shortly following the onset of the COVID-19 pandemic in 2020. It raises issues around inclusivity of online learning, pedagogy, unintended consequences of digitalisation and privacy, when moving to online teaching that are relevant both during the pandemic and in the longer term.
Background
The coagulation status of dogs with liver disease is difficult to predict using conventional coagulation testing.
Hypothesis/Objectives
To evaluate thromboelastography (TEG) results and ...associations with conventional coagulation results and indicators of disease severity and prognosis in dogs with chronic hepatopathies (CH).
Animals
Twenty‐one client‐owned dogs.
Methods
Dogs with CH were prospectively (10 dogs) and retrospectively (11 dogs) enrolled from 2008 to 2014. Kaolin‐activated TEG was performed and compared with reference intervals by t‐tests or Mann‐Whitney tests. Correlation coefficients for TEG results and conventional coagulation and clinicopathologic results were determined. Significance was set at P < .05.
Results
Dogs with CH had significant increases in R (5.30 min vs 4.33 min), K (3.77 min vs 2.11 min), and LY30 (4.77% vs 0.68%) and decreased angles (55.3° vs 62.4°). G value defined 9 of 21, 7 of 21, and 5 of 21 dogs as normocoagulable, hypercoagulable, and hypocoagulable, respectively. G and MA were correlated with fibrinogen (r = 0.68, 0.83), prothrombin time (PT; r = −0.51, −0.53), and activated partial thromboplastin time (aPTT; r = −0.50, −0.50). K was correlated with PT (r = 0.75) and protein C activity (r = −0.92). Angle was correlated with aPTT (r = −0.63). Clinical score was correlated with PT (r = 0.60), MA (r = −0.53), and R (r = −0.47). Dogs with hyperfibrinolysis (LY30 > 3.04%; 5 of 21) had significantly higher serum transaminase activities. Dogs with portal hypertension had significantly lower G, MA, and angle and prolonged, K, R, and PT.
Conclusions and Clinical Relevance
Dogs with CH have variable TEG results. Negative prognostic indicators in CH correlate with hypocoagulable parameters on TEG. Hyperfibrinolysis in dogs with CH is associated with high disease activity.
The purpose of this review was to identify, summarize, and critically appraise studies on dietary salt and health outcomes that were published from August 2016 to March 2017. The search strategy was ...adapted from a previous systematic review on dietary salt and health. Studies that meet standards for methodological quality criteria and eligible health outcomes are reported in detailed critical appraisals. Overall, 47 studies were identified and are summarized in this review. Two studies assessed all‐cause or disease‐specific mortality outcomes, eight studies assessed morbidity reduction‐related outcomes, three studies assessed outcomes related to symptoms/quality of life/functional status, 25 studies assessed blood pressure (BP) outcomes and other clinically relevant surrogate outcomes, and nine studies assessed physiologic surrogate outcomes. Eight of these studies met the criteria for outcomes and methodological quality and underwent detailed critical appraisals and commentary. Five of these studies found adverse effects of salt intake on health outcomes (BP; death due to kidney disease and initiation of dialysis; total kidney volume and composite of kidney function; composite of cardiovascular disease (CVD) events including, and risk of mortality); one study reported the benefits of salt restriction in chronic BP and two studies reported neutral results (BP and risk of CKD). Overall, these articles confirm the negative effects of excessive sodium intake on health outcomes.
The deuterium-to-hydrogen (D/H) ratio in strongly bound water or hydroxyl groups in ancient martian clays retains the imprint of the water of formation of these minerals. Curiosity's Sample Analysis ...at Mars (SAM) experiment measured thermally evolved water and hydrogen gas released between 550° and 950°C from samples of Hesperian-era Gale crater smectite to determine this isotope ratio. The D/H value is 3.0 (±0.2) times the ratio in standard mean ocean water. The D/H ratio in this ∼3-billion-year-old mudstone, which is half that of the present martian atmosphere but substantially higher than that expected in very early Mars, indicates an extended history of hydrogen escape and desiccation of the planet.
Portal Vein Thrombosis in 33 Dogs: 1998–2011 Respess, M.; O'Toole, T.E.; Taeymans, O. ...
Journal of veterinary internal medicine,
March-April 2012, Letnik:
26, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Background
Portal vein thrombosis (PVT) has been reported infrequently in dogs.
Objectives
To characterize the presentation, associated disease conditions, and outcome in dogs with PVT.
Animals
...Client‐owned dogs with a diagnosis of PVT and a complete medical record.
Methods
Records were retrospectively analyzed for presentation, history, physical examination, clinicopathologic data, diagnostic imaging, treatment, and outcome.
Results
Thirty‐three dogs were included. Common clinical signs were vomiting, diarrhea, abdominal pain, ascites, and signs of hypovolemic shock. Associated disease conditions included hepatic (14/33), neoplastic (7/33), immune (5/33), and infectious (4/33) diseases, protein‐losing nephropathy (3/33), hyperadrenocorticism (2/33), protein‐losing enteropathy (1/33), and pancreatitis (1/33). Fourteen dogs were receiving glucocorticoids at the time of diagnosis. Twenty‐nine dogs had at least 1 predisposing condition for venous thrombosis, and 11 had 2 or more. Thrombocytopenia (24/33), increased liver enzyme activity (23/33), and hypoalbuminemia (20/33) were common laboratory abnormalities. Clinical syndromes at the time of PVT diagnosis included shock (16/33), systemic inflammatory response syndrome (SIRS), (13/33) and disseminated intravascular coagulation (3/33). Twenty‐four dogs had acute and 9 had chronic PVT. Multiple thrombi were found in 17/33 dogs. Nineteen dogs survived to discharge. Dogs treated with anticoagulant therapy were more likely, whereas those with acute PVT, multiple thromboses or SIRS were less likely to survive.
Conclusions and Clinical Importance
Hepatic disease is a common pre‐existing condition in dogs with PVT. PVT should be considered in dogs with risk factors for venous thrombosis presenting with abdominal pain, ascites, and thrombocytopenia. Studies evaluating anticoagulant therapy in the management of PVT are warranted.
Dynamic sexual dichromatism is a temporary colour change between the sexes and has evolved independently in a wide range of anurans, many of which are explosive breeders wherein males physically ...compete for access to females. Behavioural studies in a few species indicate that dynamic dichromatism functions as a visual signal in large breeding aggregations; however, the prevalence of this trait and the social and environmental factors underlying its expression are poorly understood. We compiled a database of 178 anurans with dynamic dichromatism that include representatives from 15 families and subfamilies. Dynamic dichromatism is common in two of the three subfamilies of hylid treefrogs. Phylogenetic comparative analyses of 355 hylid species (of which 95 display dynamic dichromatism) reveal high transition rates between dynamic dichromatism, ontogenetic (permanent) dichromatism and monochromatism reflecting the high evolutionary lability of this trait. Correlated evolution in hylids between dynamic dichromatism and forming large breeding aggregations indicates that the evolution of large breeding aggregations precedes the evolution of dynamic dichromatism. Multivariate phylogenetic logistic regression recovers the interaction between biogeographic distribution and forming breeding aggregations as a significant predictor of dynamic dichromatism in hylids. Accounting for macroecological differences between temperate and tropical regions, such as seasonality and the availability of breeding sites, may improve our understanding of ecological contexts in which dynamic dichromatism is likely to arise in tropical lineages and why it is retained in some temperate species and lost in others.
Portal hypertension (PH) is the result of increased vascular resistance in the portal circulation, increased portal venous blood flow, or both. In veterinary medicine, where portal pressure is seldom ...measured directly, the diagnosis of PH often is inferred from identification of associated complications including multiple acquired portosystemic shunts, ascites, and hepatic encephalopathy. Likewise, treatment of PH primarily is aimed at controlling these complications. The goal of this review is to provide an update on the pathophysiology, diagnosis, and treatment of PH. The review draws from information in the veterinary hepatology literature, reviews, and consensus statements in human hepatology and the literature on experimental models of PH.
The Global Burden of Disease (GBD) 2010 study estimated national salt intake for 187 countries based on data available up to 2010. The purpose of this review was to identify studies that have ...measured salt intake in a nationally representative population using the 24‐hour urine collection method since 2010, with a view to updating evidence on population salt intake globally. Studies published from January 2011 to September 2018 were searched for from MEDLINE, Scopus, and Embase databases using relevant terms. Studies that provided nationally representative estimates of salt intake among the healthy adult population based on the 24‐hour urine collection were included. Measured salt intake was extracted and compared with the GBD estimates. Of the 115 identified studies assessed for eligibility, 13 studies were included: Four studies were from Europe, and one each from the United States, Canada, Benin, India, Samoa, Fiji, Barbados, Australia, and New Zealand. Mean daily salt intake ranged from 6.75 g/d in Barbados to 10.66 g/d in Portugal. Measured mean population salt intake in Italy, England, Canada, and Barbados was lower, and in Fiji, Samoa, and Benin was higher, in recent surveys compared to the GBD 2010 estimates. Despite global targets to reduce population salt intake, only 13 countries have published nationally representative salt intake data since the GBD 2010 study. In all countries, salt intake levels remain higher than the World Health Organization's recommendation, highlighting the need for additional global efforts to lower salt intake and monitor salt reduction strategies.
AIMS: Decontamination and remediation of a site contaminated by the accidental or intentional release of fully virulent Bacillus anthracis spores are difficult, costly and potentially damaging to the ...environment. Development of novel decontamination strategies that have minimal environmental impacts remains a high priority. Although ungerminated spores are amongst the most resilient organisms known, once exposed to germinants, the germinating spores, in some cases, become susceptible to antimicrobial environments. We evaluated the concept that once germinated, B. anthracis spores would be less hazardous and significantly easier to remediate than ungerminated dormant spores. METHODS AND RESULTS: Through in vitro germination and sensitivity assays, we demonstrated that upon germination, B. anthracis Ames spores and Bacillus thuringiensis Al Hakam spores (serving as a surrogate for B. anthracis) become susceptible to environmental stressors. The majority of these germinated B. anthracis and B. thuringiensis spores were nonviable after exposure to a defined minimal germination‐inducing solution for prolonged periods of time. Additionally, we examined the impact of potential secondary disinfectant strategies including bleach, hydrogen peroxide, formaldehyde and artificial UV‐A, UV‐B and UV‐C radiation, employed after a 60‐min germination‐induction step. Each secondary disinfectant employs a unique mechanism of killing; as a result, germination‐induction strategies are better suited for some secondary disinfectants than others. CONCLUSIONS: These results provide evidence that the deployment of an optimal combination strategy of germination‐induction/secondary disinfection may be a promising aspect of wide‐area decontamination following a B. anthracis contamination event. SIGNIFICANCE AND IMPACT OF THE STUDY: By inducing spores to germinate, our data confirm that the resulting cells exhibit sensitivities that can be leveraged when paired with certain decontamination measures. This increased susceptibility could be exploited to devise more efficient and safe decontamination measures and may obviate the need for more stringent methods that are currently in place.