Writing critically about science: a curriculum structure for animal scientists

Critical scientific writing skills are important generic or transferable skills that are effectively developed in well designed university undergraduate science programs. Preparation and oral defense of a research thesis form a capstone element of degrees that offer an integrated honours program, such as the Bachelor of Animal and Veterinary Biosciences (BAnVetBioSc) offered at The University of Sydney. Recent research shows that the best way to achieve these high quality learning outcomes is through a research-led curriculum. This does more than simply engage students as an audience for research; rather they are active participants, synthesising knowledge as part of a research community (Brew 2006). The point of departure for planning such a research-led curriculum is to start with the end in mind. This means starting with a clear statement of the learning outcomes, the disciplinary knowledge, personal attributes and generic skills in scientific communication which graduates must reliably demonstrate in a range of different contexts (Biggs and Tang 2007). Students actively construct the necessary knowledge, skills and attitudes (graduate attributes) through active engagement in learning about the discipline. Learning is optimised when students are immersed in authentic, meaningful learning activities that are closely aligned to the tasks they will face after graduation (Ramsden 2003) and where they are guided by timely, constructive feedback and reflection on their progress. Designing learning and assessment tasks that create this environment is a challenge for curriculum co-ordinators and teachers. Implementation is tricky in the large classes of Australian universities (Ramsden 2003) as many authentic research-based learning activities are too staff and resource costly to run. The framework used to guide students into productive learning activity is the key to overcoming these constraints. Students need clarity on where they are heading with their learning, to feel some personal commitment to the goals and sustain steady work on challenging tasks, with staff and peer support (Biggs and Tang 2007). These are the conditions that support conceptual change and deep, lasting learning (Prosser and Trigwell 1999). Undergraduate students vary in their written communication quality and many require considerable guided practice over several years to develop clear, accurate, scientific writing skills. Consequently, designing a curriculum to develop critical scientific writing means engaging students in writing and reflecting on scientific writing early and often and being clear on the standard of achievement required. Students benefit from a well planned scaffold of learning activities, aligned to learning outcomes and graduate attributes, with teaching support that can be gradually removed as they gain independence (Biggs and Tang 2007). Planning development of critical writing skills can be challenging in a four year degree program that offers subject choice. A semesterised, packed program makes it unlikely that every unit of study will be have the time and resources needed to develop scientific writing along with the range of other disciplinary and generic skills that are required. Therefore, whole-of-degree strategies and careful oversight are needed to be certain that no student fails to meet the required standards for critical scientific writing. This study evaluates the impact of an aligned series of peer assessed tasks in Year 1 to Year 3 on BAnVetBioSc students’ experience of learning and readiness for fourth year research projects

An application of student learner profiling: comparison of students in different degree programs

The ability to profile students by assessing their approaches to study and conceptions of discipline is valuable for educators at all levels. Detailed analysis of these factors has been undertaken in science disciplines at the University of Sydney to (i) determine the academic profiles of students in the cohorts we teach; and (ii) determine whether our teaching practices and the learning environment we provide stimulate the development of the student profiles we regard as desirable in a science graduate and, ultimately, in the professional scientist. At tertiary level, this analysis is complicated by the various degree programs that intersect in compulsory or service units of study, particularly at the first year level, and it is therefore essential that we understand the extent to which we are serving students in all degree programs. Our first year biology classes are large (up to 1500) and the unit Concepts in Biology (semester 1) is both a pre-requisite for further study in Biology and a compulsory service course for a range of degree programs (e.g. Medical Biotechnology, Pharmacy, Nutrition). We performed a cluster analysis on survey data combining measures of student approaches to study, conceptions of biology and performance in assessment after completing one semester of biology and examined the proportions of students in each of four clusters: two ‘positive’ (deep achievers and enthusiastic achievers) and two with less desirable profiles (surface strategists and neutral). Chi-squared analysis indicated no significant difference in distribution of students enrolled in Arts, Science and Pharmacy between the four clusters (p = 0.104). A significant difference was, however, detected at the level of science degree program (p < 0.002), with the Bachelor of Science (Marine) and Bachelor of Science contributing most to the difference. Implications of our analysis and further applications of learner profiling for informing improvements in science curricula, teaching and assessment will be discussed

Discrete seasonal hydroclimate reconstructions over northern Vietnam for the past three and a half centuries

We present a 350-year hydroclimatic year (HY) index for northern Vietnam derived from three discrete seasonal reconstructions from tree rings: an index of autumn rainfall from the earlywood widths of Chinese Douglas fir (Pseudotsuga sinensis), the first such record from this species, and two nearby published Palmer Drought Severity Index (PDSI) reconstructions from cypress (Fokienia hodginsii) tree rings for spring and summer, respectively. Autumn rainfall over the study region constitutes only around 9% of the annual total, but its variability is strongly linked to the strength of the atmospheric gradient over Asia during the transition from the boreal summer to winter monsoons. Deficit or surplus of autumn rainfall enhances or mitigates, respectively, the impact of the annual winter dry season on trees growing on porous karst hillsides. The most protracted HY drought (dry across all seasons) occurred at the turn of the twentieth century at a time of relative quiet, but a mid-to-late eighteenth century multi-year HY drought coincided with a period of great societal turmoil across mainland Southeast Asia and the Tay Son Rebellion in northern Vietnam. A mid-nineteenth century uprising accompanied by a smallpox epidemic, crop failure and famine, occurred during the worst autumn drought of the past two and a half centuries but only moderate drought in spring and summer. The “Great Vietnamese Famine” of the mid-twentieth century was dry only in autumn, with a wet spring and an average summer

Interferon-γ Regulates the Proliferation and Differentiation of Mesenchymal Stem Cells via Activation of Indoleamine 2,3 Dioxygenase (IDO)

The kynurenine pathway (KP) of tryptophan metabolism is linked to antimicrobial activity and modulation of immune responses but its role in stem cell biology is unknown. We show that human and mouse mesenchymal and neural stem cells (MSCs and NSCs) express the complete KP, including indoleamine 2,3 dioxygenase 1 (IDO) and IDO2, that it is highly regulated by type I (IFN-β) and II interferons (IFN-γ), and that its transcriptional modulation depends on the type of interferon, cell type and species. IFN-γ inhibited proliferation and altered human and mouse MSC neural, adipocytic and osteocytic differentiation via the activation of IDO. A functional KP present in MSCs, NSCs and perhaps other stem cell types offers novel therapeutic opportunities for optimisation of stem cell proliferation and differentiation

Genotype-dependent associations between serotonin transporter gene (SLC6A4) DNA methylation and late-life depression

International audienceBACKGROUND: Disrupted serotonergic signaling is often a feature of depression and the role of the serotonin transporter gene (SLC6A4), responsible for serotonin re-uptake, has received much attention in this regard. Most studies have focused on the polymorphic 5-HTTLPR upstream repeat, or DNA methylation at the promoter CpG island. Few studies have explored the influence of genetic variation across the gene on DNA methylation, and their combined association with depression risk. The aim of this study was to determine whether genetic variation in the SLC6A4 gene influences promoter DNA methylation, and whether these are associated with depression status.METHOD: The ESPRIT study involves a community-based population of older individuals (> 65 years of age). Major depressive disorder (MDD) was diagnosed according to DSM-IV (American Psychiatric Association, 1994) criteria, and severe depressive symptoms assessed by the Centre for Epidemiological Studies Depression (CES-D) Scale. Sequenom MassARRAY was used to measure SLC6A4 methylation status (n = 302).RESULTS: Nominally significant associations were observed between SLC6A4 genetic variants (5-HTTLPR, rs140700, rs4251417, rs6354, rs25528, rs25531) and DNA methylation at several CpG sites. In multivariate regression, DNA methylation was associated with depression status, but only in the presence of specific genotypes. In individuals homozygous for the short 5-HTTLPR and 5-HTTLPR/r25531 alleles, lower methylation at two CpGs was associated with depression (β = - 0.44 to β = - 0.31; p = 0.001 to p = 0.038).CONCLUSION: We present evidence for genotype-dependent associations between SLC6A4 methylation and depression. Genetic variants may also play a role in influencing promoter methylation levels and its association with depression

Investigation of cerebrocortical and cerebellar pathology in canine fucosidosis and comparison to aged brain

Fucosidosis is a fatal inherited neurodegenerative disease. The pathologic changes in brain which occur with progression from preclinical to late clinical disease were investigated in fucosidosis affected dogs. As aging also causes neurodegeneration and lysosomal dysfunction, pathologic markers of fucosidosis were compared to changes in the aging canine brain. Preclinical fucosidosis cerebral cortex and cerebellum revealed early increases in all neurodegenerative markers studied including apoptosis (2.1 fold), pyramidal neuronal loss (0.9 fold decrease) and Purkinje cell loss (1.2 fold decrease) compared to age matched controls. Increased axonal spheroid formation (> 100 fold in cortex, 80 fold in cerebellum), microgliosis (9.2 fold) and astrocytosis (2.1 fold in cortex and 0.5 fold in cerebellum) were distinctive features of preclinical fucosidosis brain in all regions examined. This neuropathology progressed as the dogs developed severe clinical signs, with advanced fucosidosis brain exhibiting the greatest parenchymal destruction. These measures of the neurodegenerative and inflammatory changes in fucosidosis brain will assist monitoring disease progression and response to therapy.9 page(s

Cerebellar Abiotrophy in Australian Working Kelpies Is Associated with Two Major Risk Loci

An autosomal recessive form of inherited cerebellar abiotrophy (CA) that is characterized by a degeneration of Purkinje and granule cells in the cerebellar cortex occurs in the Australian working kelpie dog breed. The clinical signs of CA include ataxia, head tremor, motor in-coordination, wide-based stance, and high-stepping gait. Investigation of clinical and pathological features indicated two closely related diseases with differences in age of onset. A genome-wide association study on 45 CA affected and 290 normal healthy Kelpies identified two significantly associated loci, one on CFA9 and a second on CFA20. Dogs homozygous for the risk haplotype on CFA20 (23 dogs) show clinical signs before ten weeks of age. Missense variants in the sixth exon of disruptor of telomeric silencing 1-like (DOT1Lp.R200Q) and in the only exon of Leucine Rich Repeat And Ig Domain Containing 3 (LINGO3p.R359C), both on CFA20, segregate with the associated risk marker which has incomplete penetrance (42%). Affected dogs homozygous for the risk haplotype on CFA9 have later onset ataxia. A missense variant in exon 5 of Vacuole Membrane Protein 1 (VMP1 p.P160Q) on CFA9 segregates as a fully penetrant Mendelian recessive with later-onset CA. Across mammals, the variety of causative loci so far identified as influencing cerebellar disorders reinforces the complexity of the pathways that contribute to cerebellar development and function, and to the pathophysiological mechanisms that may lead to cerebellar ataxia

Cluster Analysis of Tumor Suppressor Genes in Canine Leukocytes Identifies Activation State

Cells of the immune system undergo activation and subsequent proliferation in the normal course of an immune response. Infrequently, the molecular and cellular events that underlie the mechanisms of proliferation are dysregulated and may lead to oncogenesis, leading to tumor formation. The most common forms of immunological cancers are lymphomas, which in dogs account for 8%-20% of all cancers, affecting up to 1.2% of the dog population. Key genes involved in negatively regulating proliferation of lymphocytes include a group classified as tumor suppressor genes (TSGs). These genes are also known to be associated with progression of lymphoma in humans, mice, and dogs and are potential candidates for pathological grading and diagnosis. The aim of the present study was to analyze TSG profiles in stimulated leukocytes from dogs to identify genes that discriminate an activated phenotype. A total of 554 TSGs and three gene set collections were analyzed from microarray data. Cluster analysis of three subsets of genes discriminated between stimulated and unstimulated cells. These included 20 most upregulated and downregulated TSGs, TSG in hallmark gene sets significantly enriched in active cells, and a selection of candidate TSGs, p15 (CDKN2B), p18 (CDKN2C), p19 (CDKN1A), p21 (CDKN2A), p27 (CDKN1B), and p53 (TP53) in the third set. Analysis of two subsets suggested that these genes or a subset of these genes may be used as a specialized PCR set for additional analysis