625 research outputs found
The economics of potato crop rotations in southern Manitoba
Non-Peer ReviewedRapid expansion of the potato industry in Manitoba has led to increased potato
production in Manitoba. While the introduction of potatoes into current cropping systems
may provide an opportunity for producers to increase the profitability of their farming
operation, development of economically and environmentally sustainable production
systems is key to the long-term success of the industry. Currently, little information is
available about the economic and environmental impacts of such crop rotations with
respect to potato production in Canada. Recognizing the importance of sustainable
production systems, in 1998, a potato crop rotation study was established at Manitoba
Crop Diversification Center (MCDC) at Carberry to develop recommendations for
irrigated potato management in southern Manitoba. Six crop rotations ranging from two
to four years in duration, and containing potatoes in combination with oilseed, cereal
and/or legume crops, were included in this study. Each phase of each rotation was present
in each year making a total of 18 treatments. This paper discusses the economic return of
these six different crop rotations. The data with respect to all the production practices,
including storage, transport and marketing for the period of 1998 to 2001 were collected
and analyzed using a computer model developed for this purpose. Econometrics View
software was used to develop this model, and the model takes into account the whole
system for each rotation when analyzing the data. The preliminary results suggest that,
for the period of 1999 through 2000, both potato-canola and potato-oat-wheat rotations
appeared to be promising rotations. However, the poor potato yield of the potato-oatwheat
rotation in 2001 resulted in low average net income for that rotation. The higher
net benefit of the potato-canola rotation during the time period analyzed was primarily
the result of a higher proportion of the tuber yield being of marketable size, not for higher
gross tuber or canola yields. It is, however, difficult to make firm conclusions at this
point of time as to which rotation will be most profitable in the long term. This is mainly
because of the rotation treatments have only been in place since 1998 and, as such,
observed differences among rotations may be a function not only of the rotation but also
of environmental conditions and management within a given year
Stacked crop rotations and cultural practices for canola and flax yield and quality
Canola (Brassica napus L.) and flax (Linum usitatissimum L.) are important oilseed crops, but improved management practices to enhance their yields and quality are needed. We studied the effect of stacked versus alternateāyear crop rotations and traditional versus improved cultural practices on canola and flax growth, seed yield, oil concentration, and Nāuse efficiency from 2006 to 2011 in the northern Great Plains, USA. Stacked rotations were durum (Triticum turgidum L.)ādurumācanolaāpea (Pisum sativum L.) (DDCP) and durumādurumāflaxāpea (DDFP). Alternateāyear rotations were durumācanolaādurumāpea (DCDP) and durumāflaxādurumāpea (DFDP). The traditional cultural practice included a combination of conventional tillage, recommended seed rate, broadcast N fertilization, and reduced stubble height. The improved cultural practice included a combination of noātillage, increased seed rate, banded N fertilization, and increased stubble height. Canola stand count was 36ā123% greater with the improved than the traditional cultural practice in 2006, 2009, 2010, and 2011. Canola pod number and oil concentration were 3ā36% greater in the improved than the traditional practice in 2007 and 2010, but trends reversed by 5ā19% in 2008. Flax stand count was 28% greater with DFDP than DDFP in 2007 and 56% greater in the improved than the traditional practice in 2010. Flax pod number, seed weight, seed yield, N content, Nāuse efficiency, and Nāremoval index varied with crop rotations, cultural practices, and years. Canola growth and oil concentration increased with the improved cultural practice as well as flax growth, yield, and quality enhanced with alternateāyear crop rotation and the improved cultural practice in wet years
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A behavioral comparison of male and female adults with high functioning autism spectrum conditions
Autism spectrum conditions (ASC) affect more males than females in the general population. However, within ASC it is unclear if there are phenotypic sex differences. Testing for similarities and differences between the sexes is important not only for clinical assessment but also has implications for theories of typical sex differences and of autism. Using cognitive and behavioral measures, we investigated similarities and differences between the sexes in age- and IQ-matched adults with ASC (high-functioning autism or Asperger syndrome). Of the 83 (45 males and 38 females) participants, 62 (33 males and 29 females) met Autism Diagnostic Interview-Revised (ADI-R) cut-off criteria for autism in childhood and were included in all subsequent analyses. The severity of childhood core autism symptoms did not differ between the sexes. Males and females also did not differ in self-reported empathy, systemizing, anxiety, depression, and obsessive-compulsive traits/symptoms or mentalizing performance. However, adult females with ASC showed more lifetime sensory symptoms (pā=ā0.036), fewer current socio-communication difficulties (pā=ā0.001), and more self-reported autistic traits (pā=ā0.012) than males. In addition, females with ASC who also had developmental language delay had lower current performance IQ than those without developmental language delay (p<0.001), a pattern not seen in males. The absence of typical sex differences in empathizing-systemizing profiles within the autism spectrum confirms a prediction from the extreme male brain theory. Behavioral sex differences within ASC may also reflect different developmental mechanisms between males and females with ASC. We discuss the importance of the superficially better socio-communication ability in adult females with ASC in terms of why females with ASC may more often go under-recognized, and receive their diagnosis later, than males
Do adults with high functioning autism or Asperger Syndrome differ in empathy and emotion recognition?
The present study examined whether adults with high functioning autism (HFA) showed greater difficulties in (i) their self-reported ability to empathise with others and/or (ii) their ability to read mental states in othersā eyes than adults with Asperger syndrome (AS). The Empathy Quotient (EQ) and āReading the Mind in the Eyesā Test (Eyes Test) were compared in 43 adults with AS and 43 adults with HFA. No significant difference was observed on EQ score between groups, while adults with AS performed significantly better on the Eyes Test than those with HFA. This suggests that adults with HFA may need more support, particularly in mentalizing and complex emotion recognition, and raises questions about the existence of subgroups within autism spectrum conditions
Comparison of different in situ hybridization techniques for the detection of various RNA and DNA viruses
In situ hybridization (ISH) is a technique to determine potential correlations between viruses and lesions. The aim of the study was to compare ISH techniques for the detection of various viruses in different tissues. Tested RNA viruses include atypical porcine pestivirus (APPV) in the cerebellum of pigs, equine and bovine hepacivirus (EqHV, BovHepV) in the liver of horses and cattle, respectively, and Schmallenberg virus (SBV) in the cerebrum of goats. Examined DNA viruses comprise canine bocavirus 2 (CBoV-2) in the intestine of dogs, porcine bocavirus (PBoV) in the spinal cord of pigs and porcine circovirus 2 (PCV-2) in cerebrum, lymph node, and lung of pigs. ISH with self-designed digoxigenin-labelled RNA probe
A genome-wide scan for common alleles affecting risk for autism
Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 Ć 10ā8. When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner's curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 Ć 10ā8 threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C
Social interaction style of children and adolescents with high-functioning autism spectrum disorder
Qualitative differences in social interaction style exist within the autism spectrum. In this study we examined whether these differences are associated with (1) the severity of autistic symptoms and comorbid disruptive behavior problems, (2) the child's psycho-social health, and (3) executive functioning and perspective taking skills. The social interaction style of 156 children and adolescents (6-19 years) with high-functioning autism spectrum disorder (HFASD) was determined with the Wing Subgroups Questionnaire. An active-but-odd social interaction style was positively associated with symptoms of autism, attention deficit and hyperactivity. Furthermore, an active-but-odd social interaction style was negatively associated with children's psycho-social health and positively with executive functioning problems. Social interaction style explains part of the heterogeneity among children with HFASD
Recent translational research: circulating tumor cells in breast cancer patients
In breast cancer patients, hematogenous tumor cell dissemination can be detected, even at the single cell level, by applying immunocytochemical and molecular assays. Various methods for the detection of circulating tumor cells in the peripheral blood have been described. Results from recently reported studies suggest that circulating tumor cell levels may serve as a prognostic marker and for the early assessment of therapeutic response in patients with metastatic breast cancer. However, in early-stage breast cancer, the impact of circulating tumor cells is less well established than the presence of disseminated tumor cells in bone marrow; several clinical studies have demonstrated that cells of the latter type are an independent prognostic factor at primary diagnosis. In this article we briefly summarize recent studies examining the presence of circulating tumor cells in the blood and discuss further clinical applications
Inter-rater reliability and stability of diagnoses of autism spectrum disorder in children identified through screening at a very young age
To examine the inter-rater reliability and stability of autism spectrum disorder (ASD) diagnoses made at a very early age in children identified through a screening procedure around 14Ā months of age. In a prospective design, preschoolers were recruited from a screening study for ASD. The inter-rater reliability of the diagnosis of ASD was measured through an independent assessment of a randomly selected subsample of 38 patients by two other psychiatrists. The diagnoses at 23Ā months and 42Ā months of 131 patients, based on the clinical assessment and the diagnostic classifications of standardised instruments, were compared to evaluate stability of the diagnosis of ASD. Inter-rater reliability on a diagnosis of ASD versus non-ASD at 23Ā months was 87% with a weighted Īŗ of 0.74 (SE 0.11). The stability of the different diagnoses in the autism spectrum was 63% for autistic disorder, 54% for pervasive developmental disorder, not otherwise specified (PDD-NOS), and 91% for the whole category of ASD. Most diagnostic changes at 42Ā months were within the autism spectrum from autistic disorder to PDD-NOS and were mainly due to diminished symptom severity. Children who moved outside the ASD category at 42Ā months made significantly larger gains in cognitive and language skills than children with a stable ASD diagnosis. In conclusion, the inter-rater reliability and stability of the diagnoses of ASD established at 23Ā months in this population-based sample of very young children are good
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