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Waterhemp [Amaranthus tuberculatus (Moq.) J. D. Sauer] and Palmer amaranth (Amaranthus palmeri S. Watson) are troublesome weeds of row-crop production in the United States. Their dioecious reproductive systems ensure outcrossing, facilitating rapid evolution and distribution of resistances to multiple herbicides. Little is known, however, about the genetic basis of dioecy in Amaranthus species. In this work, we use restriction site–associated DNA sequencing (RAD-Seq) to investigate the genetic basis of sex determination in A. tuberculatus and A. palmeri. For each species, approximately 200 plants of each sex were sampled and used to create RAD-Seq libraries. The resulting libraries were separately bar-coded and then pooled for sequencing with the Illumina platform, yielding millions of 64-bp reads. These reads were analyzed to identify sex-specific and sex-biased sequences. We identified 345 male-specific sequences from the A. palmeri data set and 2,754 male-specific sequences in A. tuberculatus. An unexpected 723 female-specific sequences were identified in a subset of the A. tuberculatus females; subsequent research, however, indicated female specificity of these markers was limited to the population from which they were identified. Primer sets designed to specifically amplify male-specific sequences were tested for accuracy on multiple, geographically distinct populations of A. tuberculatus and A. palmeri, as well as other Amaranthus species. Two primer sets for A. palmeri and four primer sets for A. tuberculatus were each able to distinguish between male and female plants with at least 95% accuracy. In the near term, sex-specific markers will be useful to the A. tuberculatus and A. palmeri research communities (e.g., to predict sex for crossing experiments). In the long-term, this research will provide the foundational tools for detailed investigations into the molecular biology and evolution of dioecy in weedy Amaranthus species.
Background: People of aboriginal ancestry are more likely to suffer traumatic spinal cord injury (TSCI) compared to other Canadians; however, outcome studies are limited. This study aims to compare aboriginal and non-aboriginal populations with acute TSCI with respect to: pre-injury baseline, injury severity, treatment, outcomes, and length-of-stay characteristics. Methods: This was a retrospective analysis of 159 patients with TSCI prospectively enrolled in the prospective Rick Hansen Spinal Cord Injury Registry (RHSCIR), Saskatoon site between February 13, 2010 and December 17, 2016. Results: Sixty-two patients consented to the full dataset, which includes ethnic background: 21 ‘aboriginal’ (33.9%); 41 ‘non-aboriginal’ (66.1%). Aboriginal patients were younger, had fewer medical comorbidities and had similar severity of neurological injury and similar outcomes compared to non-aboriginal patients. However, the time to discharge to the community was significantly longer (median 104.0 days versus 38.5 days, p=0.021). While 35% of non-aboriginal patients were discharged home from the acute care site, no aboriginal patients were transferred home directly. Conclusions: This study suggests a need for better allocation of resources for transition to the community for First Nations patients with TSCI in Saskatchewan. We plan a further study to assess outcomes from TSCI for First Nations patients across Canada.
Background: While recent clinical trials have demonstrated immense efficacy of mechanical thrombectomy (MT) in the setting of acute stroke, there remains debate over the safety in performing this procedure under general anesthesia (GA). In the Saskatchewan Acute Stroke Pathway, all patients presenting with LVO have endovascular thrombectomy performed under GA. Methods: Data was retrospectively reviewed on 108 consecutive LVO in 2016-2017. All MT were done under GA. Anatomical location of LVO, pre-MT ASPECTS score, post-MT TICI scores and 90-day NIHSS and mRS were recorded. Results: Of 108 LVO, 103 went on to have MT. 44 were right anterior circulation, 50 were left anterior circulation and 9 were posterior circulation. Of 94 anterior circulation strokes, 47 (50.0%), 43 (45.7%) and 4 (4.3%) had good, moderate and poor collateral circulation respectively, and the average pre-MT ASPECTS was 8.6. The average pre-MT NIHSS was 14.7. 81/90 (90.0%) achieved thrombolysis in cerebral infarction (TICI) perfusion scale grade of 2b/3 after recanalization. Average documented 90-day NIHSS was 2.4 and mRS was 2.5. Overall mortality was 21/103 (20.4%). Conclusions: In the Saskatchewan acute stroke pathway, general anesthesia is a safe modality for MT. This adds to the body of evidence supporting GA as a viable option for sedation in MT.
Background: Cerebellar atrophy is characterized by loss of cerebellar tissue, with evidence on brain imaging of enlarged interfolial spaces compared to the foliae. Genetic ataxias associated with cerebellar atrophy are a heterogeneous group of disorders. We investigated the prevalence in Canada and the diagnostic yield of whole exome sequencing (WES) for this group of conditions. Methods: Between 2011 and 2017, WES was performed in 91 participants with cerebellar atrophy as part of one of two national research programs, Finding of Rare Genetic Disease Genes (FORGE) or Enhanced Care for Rare Genetic Diseases in Canada (Care4Rare). Results: A genetic diagnosis was established in 58% of cases (53/91). Pathogenic variants were found in 24 known genes, providing a diagnosis for 46/53 participants (87%), and in four novel genes, accounting for 7/53 cases (13%). 38/91 cases (42%) remained unsolved. The most common diagnoses were channelopathies in 12/53 patients (23%) and mitochondrial disorders in 9/53 (17%). Inheritance was autosomal recessive in the majority of cases. Additional clinical findings provided useful clues to some of the diagnoses. Conclusions: This is the first report on the prevalence of genetic ataxias associated with cerebellar atrophy in Canada, and the utility of WES for this group of conditions.
Introduction: In addition to its clinical utility, the Canadian Triage and Acuity Scale (CTAS) has become an administrative metric used by governments to estimate patient care requirements, emergency department (ED) funding and workload models. The electronic Canadian Triage and Acuity Scale (eCTAS) initiative aims to improve patient safety and quality of care by establishing an electronic triage decision support tool that standardizes that application of national triage guidelines across Ontario. The objective of this study was to evaluate triage times and score agreement in ED settings where eCTAS has been implemented. Methods: This was a prospective, observational study conducted in 7 hospital EDs, selected to represent a mix of triage processes (electronic vs. manual), documentation practices (electronic vs. paper), hospital types (rural, community and teaching) and patient volumes (annual ED census ranged from 38,000 to 136,000). An expert CTAS auditor observed on-duty triage nurses in the ED and assigned independent CTAS in real time. Research assistants not involved in the triage process independently recorded triage time. Interrater agreement was estimated using unweighted and quadratic-weighted kappa statistics with 95% confidence intervals (CIs). Results: 1491 (752 pre-eCTAS, 739 post-implementation) individual patient CTAS assessments were audited over 42 (21 pre-eCTAS, 21 post-implementation) seven-hour triage shifts. Exact modal agreement was achieved for 567 (75.4%) patients pre-eCTAS, compared to 685 (92.7%) patients triaged with eCTAS. Using the auditor's CTAS score as the reference standard, eCTAS significantly reduced the number of patients over-triaged (12.0% vs. 5.1%; Δ 6.9, 95% CI: 4.0, 9.7) and under-triaged (12.6% vs. 2.2%; Δ 10.4, 95% CI: 7.9, 13.2). Interrater agreement was higher with eCTAS (unweighted kappa 0.89 vs 0.63; quadratic-weighted kappa 0.91 vs. 0.71). Research assistants captured triage time for 3808 patients pre-eCTAS and 3489 post implementation of eCTAS. Median triage time was 312 seconds pre-eCTAS and 347 seconds with eCTAS (Δ 35 seconds, 95% CI: 29, 40 seconds). Conclusion: A standardized, electronic approach to performing CTAS assessments improves both clinical decision making and administrative data accuracy without substantially increasing triage time.
Free convective flow and heat transfer of nanofluid close to the inclined plate immersed in the porous medium under the effects of uniform magnetic field and solar radiation has been studied. Boundary-layer approach, Boussinesq approximation and two-phase nanofluid model have been used for a formulation of the governing equations taking into account convective-radiative heat exchange with an environment. The local similarity method has been adopted for the analysis of the considered phenomenon. The obtained equations have been solved numerically using MATLAB software. The effects of control characteristics on profiles of velocity, temperature and nanoparticles volume fraction as well as Nusselt number have been studied in detail.
Maize (Zea mays L.) grain yield is severely constrained by drought and this study was conducted to assess gains in grain yield and other traits of released maize cultivars. Twenty-three maize cultivars plus a check were evaluated under drought and well-watered conditions at Zaria and Kadawa during 2015/2016 and 2016/2017 dry seasons. The 24 cultivars were evaluated using 6 x 4 lattice design with three replications. Genotypes differed significantly for all measured traits except anthesis-silking interval (ASI), husk cover, and number of ears per plant under drought, and ASI, husk cover, and ear aspect under well-watered conditions. Under drought, grain yield ranged from 2251 kg ha−1 for SAMMAZ 31 to 4938 kg ha−1 for SAMMAZ 19, with a genetic gain of 1.93% yr−1. Under well-watered conditions, grain yield varied from 3082 kg ha−1 for SAMMAZ 37 to 5689 kg ha−1 for SAMMAZ 51, with the same genetic gain found under drought conditions. Grain yield reduction as a result of drought was 28.4% and performance under drought predicted performance under well-watered conditions better than vice versa with regression coefficient value of 0.8. Grain yield had significant correlations with all measured traits under both water conditions, except for husk cover, plant and ear heights under drought. Our data revealed that substantial genetic gains have been made in breeding for high grain yield cultivars under drought and well-watered conditions over a period of 16 years in Nigeria.
Use of antibiotics as feed additives has been reduced to avoid the hazard of drug residues, and consequently, the search for alternative natural additives has developed. Thus, the aim was to evaluate the influence of royal jelly (RJ) supplementation on milk composition, blood biochemical and antioxidant parameters of lactating ewes. Thirty-six Ossimi ewes were divided randomly into two groups (18 animals each). For a period of 4 weeks, the control group (CON) was fed a basal diet only, while the other group was fed the basal diet and supplemented with a single bolus of RJ (1000 mg/head). The RJ-supplemented ewes produced significantly higher milk protein, fat and total solids than the CON group. The RJ group had a significantly higher red blood cell count, haemoglobin content, haematocrit value and total leucocyte counts, but lower neutrophil to lymphocyte ratio when compared with the control treatment. The RJ group showed significantly higher concentrations of total antioxidant capacity, superoxide dismutase activity and glutathione in the serum compared with the control treatment. In conclusion, RJ supplements can improve the nutritive value of milk fat and the serum antioxidant activities in lactating ewes.
Laser-induced breakdown spectroscopy has been exploited to investigate the laser-produced lead plasma with and without external magnetic field. Plasma on the lead surface was generated by focusing a beam of a Nd:YAG laser (532 nm). An external magnetic field was applied across the laser-produced plasma; its value was varied from 0.3 to 0.7 T and the time-integrated spectra were captured at different time delays. Maximum enhancement in the neutral and ionic line intensities have been observed at 130 mJ laser energy. The neutral line of Pb at 368.34 nm reveals an enhancement factor of nearly 1.3, 1.6, and 2.3 at 0.3, 0.5, and 0.7 T, whereas the Pb ionic line at 424.49 nm shows enhancement factor of approximately 2.8 and 4.2 at 0.3 and 0.7 T. The magnetic field effects on various plasma parameters such as plasma temperature, electron number density, and emission line intensities have also been investigated. The plasma parameter “β” is found to be <1 in all the experimental conditions which signifies that the enhancement in the signal intensity is due to the plasma confinement. The increase in the emission signal intensity, number density as well as plasma temperature is observed with increasing laser energy and magnetic field. The spatial and temporal behavior reveals that the plasma temperature and electron number density decrease slowly in the applied magnetic field due to the deceleration of the plasma plume. The optimized conditions for the maximum plasma confinement and the emission intensity enhancement are observed at 130 mJ laser energy at 0.7 T magnetic field.
Adenoid hypertrophy is a common cause of upper airway obstruction, and adenoidectomy is one of the most frequently performed operations in children. Topical nasal steroids can act directly on nasopharyngeal lymphoid tissue to decrease its reactive inflammatory changes and potentially reduce its size.
To study the light microscopic changes in adenoidal lymphoid tissue after one month of topical steroid use.
Twenty-six children with adenoid hypertrophy grade 3 scheduled for adenoidectomy were randomly divided into two equal groups: one group received mometasone furoate aqueous nasal spray (Nasonex) 100 mcg/day for four weeks, and a control group received nasal normal saline 0.9 per cent for four weeks. The removed adenoids were examined histopathologically.
Adenoidal tissue from the mometasone group had less reactive germinal centres and less spongiosis compared to the control group. The latter showed proliferating, reactive, variable sized and shaped lymphoid follicles, with congested blood vessels in the interfollicular areas.
The use of intranasal mometasone furoate aqueous nasal spray (Nasonex) for one month reduced adenoidal tissue reactive cellular changes and its vascularity. This is, however, a pilot study; a longer treatment period is needed to assess the effect of treatment on adenoidal size.
The relative velocity and extra pressure drop of a single vesicle flowing through a square microchannel are quantified via boundary element simulations, lubrication theory and microfluidic experiments. The vesicle is modelled as a fluid sac enclosed by an inextensible, fluidic membrane with a negligible bending stiffness. All results are parametrized in terms of the vesicle sphericity (i.e. the reduced volume) and flow confinement (i.e. the ratio of the vesicle radius to the channel hydraulic radius). Direct comparison is made to previous studies of vesicle flow through circular tubes, revealing several distinct features of the square-channel geometry. Firstly, fluid in the suspending medium bypasses the vesicle through the corners of the channel, which in turn reduces the dissipation created by the vesicle. Secondly, the absence of rotational symmetry about the channel axis permits surface circulation in the membrane (tank treading), which in turn reduces the vesicle’s speed. At very high confinement, both theory and experiment indicate that the vesicle’s speed can be reduced below the mean speed of the suspending fluid through this mechanism. Finally, the contact area for lubrication is greatly reduced in the square-duct geometry, which in turn weakens the stress singularity predicted by lubrication theory. This fact directly leads to a breakdown of the lubrication approximation at low flow confinement, as verified by comparison to boundary element simulations. Since the only distinct property assumed of the membrane is its ability to preserve surface area locally, it is expected that the results of this study are applicable to other types of soft particles with immobilized surfaces (e.g. Pickering droplets, gel beads and biological cells).
This case report illustrates an unusual case of a dural arteriovenous fistula and an associated encephalocele presenting as otitis media with effusion.
A 53-year-old man presented with right-sided hearing loss and aural fullness of 2 years’ duration. Examination revealed ipsilateral post-auricular pulsatile tenderness. Computed tomography showed transcalvarial channels suggestive of dural arteriovenous fistula. Further magnetic resonance imaging demonstrated the presence of a temporal encephalocele herniating through the tegmen tympani defect, as well as the abnormal vascularity. Angiography confirmed a Cognard type I dural arteriovenous fistula, which is being managed conservatively. Surgical repair of the encephalocele was recommended but declined by the patient.
Dural arteriovenous fistula is an uncommon intracranial vascular malformation rarely seen by otolaryngologists, with pulsatile tinnitus being the usual presentation. To our knowledge, this is the first reported case of dural arteriovenous fistula presenting with conductive hearing loss and otalgia.
Several Apriori algorithm implementations for mining association rules have been proposed in the literature using the Hadoop-MapReduce framework and, more recently, Spark. However, none of the works have made a detailed assessment of its performance, for example, comparing it with other implementations in various characteristics of data sets. In this work, we present a review of the main algorithms proposed for Hadoop-MapReduce and compared their implementations in a single environment under several different situations. Moreover, these algorithms had their implementations adapted to Spark, and also compared under the same circumstances. Based on the results of the experiments, we present a framework for recommending the Apriori implementation most appropriate for solving a given problem, according to the data set characteristics and minimum required support. The results show that Spark implementations overcome Hadoop-MapReduce implementations at runtime in most experiments. However, there is no single implementation that is the best in all the evaluated situations.
Pulmonary hypertension with transposition of the great arteries is associated with significant morbidity and mortality. At the worst end of the spectrum are patients who undergo extracorporeal support perioperatively. We describe our experience with three patients who received preoperative extracorporeal support and separated from cardiopulmonary bypass successfully on conventional postoperative care, with no significant deficits on follow-up.
Co-circulation of Chikungunya and Dengue viral infections (CHIKV and DENV) have been reported mainly due to transmission by common Aedes vector. The purpose of the study was to identify and characterise the circulating strains of CHIKV and DENV in DENV endemic region of New Delhi during 2016. CHIKV and DENV were identified in the blood samples (n = 130) collected from suspected patients by RT-PCR. CHIKV was identified in 26 of 65 samples (40%). Similarly, DENV was detected in 48 of 120 samples (40%). Co-infection with both the viruses was identified in five (9%) of the samples. Interestingly, concurrent infection with DENV, CHIKV and Plasmodium vivax was detected in two samples. CHIKV strains (n = 11) belonged to the ECSA genotype whereas DENV-3 sequences (n = eight) clustered in Genotype III by phylogenetic analysis. Selection pressure of E1 protein of CHIKV and CprM protein of DENV-3 revealed purifying selection with four and two positive sites, respectively. Four amino acids of the CHIKV were positively selected and had high entropy suggesting probable variations. Co-circulation of both viruses in DENV endemic regions warrants effective monitoring of these emerging pathogens via comprehensive surveillance for implementation of effective control measures.
Microscopic myringoplasty is the most frequently performed procedure for repairing tympanic membrane perforations. The endoscopic transcanal approach bypasses the narrow ear canal segment and provides a wider view.
An open-label randomised clinical trial was conducted on 56 patients with small anterior tympanic membrane perforations. Perforations were repaired with an endoscopic push-through technique (n = 28) or a microscopic underlay technique (n = 28). Follow up was conducted using endoscopic examination and pure tone audiometry three months’ post-operatively.
Graft success rate was 92.9 per cent in the endoscopic group versus 85.7 per cent in the microscopic group. The corresponding pre-operative mean air–bone gaps were 17.4 dB and 18.5 dB, improving to 6.1 dB and 9.3 dB post-operatively (p > 0.05). Mean air–bone gap closure was 11.4 dB in the endoscopic group and 9.2 dB in the microscopic group (p > 0.05). Mean operative time and estimated blood loss were 37.0 minutes and 29 ml in the endoscopic group, versus 107 minutes and 153 ml in the microscopic group (both p < 0.05).
The endoscopic push-through technique for anterior tympanic membrane perforations is as effective as microscopic underlay myringoplasty; furthermore, it is less invasive and takes less operative time.