Evaluating the Constructionist Approach in Entrepreneurship Education

In trying to apply a ‘new’ approach in education, we used Löbler’s (2006) ten principles for entrepreneurship education. After two years of fine-tuning and improving the programme, we were interested in evaluating it and comparing it to other learning approaches mentioned in the literature and used in practice. The goal is twofold: Firstly, we wanted to find out whether the ‘constructionist’ learning environment does support autonomy in thinking and doing. Secondly, we were interested in figuring out if the students learned more and kept working harder while being more motivated on their projects compared to the other learning environments. The results show that this kind of ‘constructionist’ coursework is superior with regard to many criteria and preferred by the students compared to the other learning approaches. The students also reported that they worked with much more enthusiasm and delight. Our analysis shows that the ten principles are working in practice and could be an advantage for students and teachers

Evaluating the Constructionist Approach in Entrepreneurship Education

In trying to apply a ‘new’ approach in education, we used Löbler’s (2006) ten principles for entrepreneurship education. After two years of fine-tuning and improving the programme, we were interested in evaluating it and comparing it to other learning approaches mentioned in the literature and used in practice. The goal is twofold: Firstly, we wanted to find out whether the ‘constructionist’ learning environment does support autonomy in thinking and doing. Secondly, we were interested in figuring out if the students learned more and kept working harder while being more motivated on their projects compared to the other learning environments. The results show that this kind of ‘constructionist’ coursework is superior with regard to many criteria and preferred by the students compared to the other learning approaches. The students also reported that they worked with much more enthusiasm and delight. Our analysis shows that the ten principles are working in practice and could be an advantage for students and teachers

Thermodynamically Consistent Force Field for Molecular Dynamics Simulations of Alkaline-Earth Carbonates and Their Aqueous Speciation

In recent years atomistic simulations have become increasingly important in providing molecular insight to complement experiments. Even for the seemingly simple case of ion-pair formation a detailed atomistic picture of the structure and relative stability of the contact, solvent-shared and solvent-separated ion pairs can only be readily achieved by computer simulation. Here a new force field parametrization for the alkaline-earth carbonate interactions in water has been developed by fitting against experimental thermodynamic and structural data. We demonstrate that the present force field can accurately reproduce the dynamics and thermodynamics of the ions in solution, which is the key to producing quantitatively accurate data that can be compared against experiment

Meal-derived glucagon responses are related to lower hepatic phosphate concentrations in obesity and type 2 diabetes

Aim. - Type 2 diabetes (T2D) alters glucagon, glucagon-like peptide (GLP)-1, glucose-dependent insulinotropic polypeptide (GIP) and hepatic energy metabolism, yet the possible relationships remain unclear.Methods. - In this observational study, lean insulin-sensitive control subjects (BMI: 23.2 +/- 1.5 kg/m(2)), age-matched insulin-resistant obese subjects (BMI: 34.3 +/- 1.7 kg/m(2)) and similarly obese elderly T2D patients (BMI: 32.0 +/- 2.4 kg/m(2)) underwent mixed-meal tolerance tests (MMTTs), and assessment of hepatic gamma ATP, inorganic phosphate (P-i) and lipids using P-31/H-1 magnetic resonance spectroscopy. Meal-induced secretion of glucagon and incretins was calculated from incremental areas under the concentration-time curves (iAUCs). Peripheral and adipose tissue insulin sensitivity were assessed from time courses of circulating glucose, insulin and free fatty acids.Results. - MMTT-derived peripheral insulin sensitivity was lowest in T2D patients (P &lt;0.001), while glucagon concentrations were comparable across all three groups. At 260 min, GLP-1 was lower in T2D patients than in controls, whereas GIP was lowest in obese individuals. Fasting glucagon concentrations correlated positively with fasting (r = 0.60) and postprandial hepatocellular lipid levels (160 min: r= 0.51, 240 min: r = 0.59), and negatively with adipose tissue insulin sensitivity (r = -0.73). Higher meal-induced glucagon release (iAUC(0)(-260) (min)) correlated with lower fasting (r = -0.62) and postprandial P(i )levels (160 min: r = -0.43, 240 min: r = -0.42; all P &lt;0.05). Higher meal-induced release of GIP (iAUC(0-260) (min)) correlated positively with fasting (r = 0.54) and postprandial serum triglyceride concentrations (iAUC(0-260 min, )r = 0.54; all P &lt;0.01).Conclusion. - Correlations between fasting glucagon and hepatic lipids and between meal-induced glucagon and hepatic P-i suggest a role for glucagon in hepatic energy metabolism. (C) 2018 Elsevier Masson SAS. All rights reserved.</p

APACHE III outcome prediction in patients admitted to the intensive care unit after liver transplantation: a retrospective cohort study

<p>Abstract</p> <p>Background</p> <p>The Acute Physiology and Chronic Health Evaluation (APACHE) III prognostic system has not been previously validated in patients admitted to the intensive care unit (ICU) after orthotopic liver transplantation (OLT). We hypothesized that APACHE III would perform satisfactorily in patients after OLT</p> <p>Methods</p> <p>A retrospective cohort study was performed. Patients admitted to the ICU after OLT between July 1996 and May 2008 were identified. Data were abstracted from the institutional APACHE III and liver transplantation databases and individual patient medical records. Standardized mortality ratios (with 95% confidence intervals) were calculated by dividing the observed mortality rates by the rates predicted by APACHE III. The area under the receiver operating characteristic curve (AUC) and the Hosmer-Lemeshow C statistic were used to assess, respectively, discrimination and calibration of APACHE III.</p> <p>Results</p> <p>APACHE III data were available for 918 admissions after OLT. Mean (standard deviation [SD]) APACHE III (APIII) and Acute Physiology (APS) scores on the day of transplant were 60.5 (25.8) and 50.8 (23.6), respectively. Mean (SD) predicted ICU and hospital mortality rates were 7.3% (15.4) and 10.6% (18.9), respectively. The observed ICU and hospital mortality rates were 1.1% and 3.4%, respectively. The standardized ICU and hospital mortality ratios with their 95% C.I. were 0.15 (0.07 to 0.27) and 0.32 (0.22 to 0.45), respectively.</p> <p>There were statistically significant differences in APS, APIII, predicted ICU and predicted hospital mortality between survivors and non-survivors. In predicting mortality, the AUC of APACHE III prediction of hospital death was 0.65 (95% CI, 0.62 to 0.68). The Hosmer-Lemeshow C statistic was 5.288 with a p value of 0.871 (10 degrees of freedom).</p> <p>Conclusion</p> <p>APACHE III discriminates poorly between survivors and non-survivors of patients admitted to the ICU after OLT. Though APACHE III has been shown to be valid in heterogenous populations and in certain groups of patients with specific diagnoses, it should be used with caution – if used at all – in recipients of liver transplantation.</p

Glacial-Interglacial changes in moisture balance and the impact on vegetation in the southern hemisphere tropical Andes (Bolivia/Peru)

A palynological investigation of the last glacial-interglacial cycle in the southern hemisphere tropical Andes reveals changes in the moisture balance as the main driver in vegetation change. Thirty accelerated mass spectrometry radiocarbon dates, biostratigraphy and tephra correlation reveal that a 119 metre sediment core recovered from the Huiñaimarca sub-basin of Lake Titicaca (16.0° to 17.5° S, 68.5° to 70° W; 3810 masl) contains sediments covering >151,000 years. Correlation of aridity indicators with precessional variations in insolation is used to fine tune the structure of the age-depth curve within this period. Variations in Isoëtes concentration (above/below 10,000 grains/cm3) identify the extent of shallow water environments. Examination of other palaeolimnological indicators (Pediastrum) and consideration of the bathymetry of the Huiñaimarca sub-basin allow the reconstruction of lake level fluctuations. These data indicate five wet/dry cycles between c. 151,000 and 14,200 cal yr BP. High stands are suggested during the transition into (c. 134,000 cal yr BP), and out of (c. 114,000, 92,000 cal yr BP), the last interglacial,and during full glacial conditions (c. 70,000 and 45,000 cal yr BP). These cycles are superimposed on a general trend of deepening lake levels through the glacial period. This interpretation is supported by correlation with sediments from Salar de Uyuni (20oS, 68oW; 3653 masl). The youngest wet episode is concurrent with palaeolake Minchin (c. 45,000 cal yr BP), with further evidence for an additional wet period commencing c. 28,000 cal yr BP, concomitant with palaeolake Tauca. The timing of lake level fluctuations is also supported by palaeoshoreline reconstructions from the Uyuni-Poopó region. However, our data do not suggest a major peak in lake level in Huiñaimarca during the Ouki lake cycle (c. 120,000-98,000 cal yr BP) as inferred from U-Th ages obtained from palaeoshorelines around Lago Poopó. The most extreme dry event occurs during the last interglacial period and resulted in a sedimentary hiatus tentatively dated to c. 121,000-129,000 cal yr BP. The observed wet/dry cycles are shown to have a marked and rapid impact on the vegetation. The aridity of the last interglacial promoted a community dominated by Chenopodiaceae/Amaranthacae, with no modern Andean analogue. Polylepis/Acaena pollen is also shown to fluctuate markedly (0-20%), particularly during the transitions into, and out of, the last interglacial. It is probable that this pollen taxon is primarily representative of the high altitude arboreal genus Polylepis, which is a key component of highly biodiverse Andean woodlands today. Rapid fluctuations indicate the sensitivity of this ecosystem to natural environmental pressure and potential vulnerability to future human impact and climate change. The 100,000 year (eccentricity) solar cycle is shown to be the major controlling factor in moisture balance and vegetation over the last glacial-interglacial cycle. However, significant fluctuations in moisture balance are also evident on timescales considerably shorter than the full glacial-interglacial cycle. We have linked these to precessional (21,000 year) forcing. Nevertheless, precise independent dating during the full glacial cycle is required to confirm the importance of this forcing mechanism

Two-Photon Imaging of Cortical Surface Microvessels Reveals a Robust Redistribution in Blood Flow after Vascular Occlusion

A highly interconnected network of arterioles overlies mammalian cortex to route blood to the cortical mantle. Here we test if this angioarchitecture can ensure that the supply of blood is redistributed after vascular occlusion. We use rodent parietal cortex as a model system and image the flow of red blood cells in individual microvessels. Changes in flow are quantified in response to photothrombotic occlusions to individual pial arterioles as well as to physical occlusions of the middle cerebral artery (MCA), the primary source of blood to this network. We observe that perfusion is rapidly reestablished at the first branch downstream from a photothrombotic occlusion through a reversal in flow in one vessel. More distal downstream arterioles also show reversals in flow. Further, occlusion of the MCA leads to reversals in flow through approximately half of the downstream but distant arterioles. Thus the cortical arteriolar network supports collateral flow that may mitigate the effects of vessel obstruction, as may occur secondary to neurovascular pathology

Mitochondrial Cox1 Sequence Data Reliably Uncover Patterns of Insect Diversity But Suffer from High Lineage-Idiosyncratic Error Rates

The demand for scientific biodiversity data is increasing, but taxonomic expertise is often limited or not available. DNA sequencing is a potential remedy to overcome this taxonomic impediment. Mitochondrial DNA is most commonly used, e.g., for species identification ("DNA barcoding"). Here, we present the first study in arthropods based on a near-complete species sampling of a family-level taxon from the entire Australian region. We aimed to assess how reliably mtDNA data can capture species diversity when many sister species pairs are included. Then, we contrasted phylogenetic subsampling with the hitherto more commonly applied geographical subsampling, where sister species are not necessarily captured. We sequenced 800 bp cox1 for 1,439 individuals including 260 Australian species (78% species coverage). We used clustering with thresholds of 1 to 10% and general mixed Yule Coalescent (GMYC) analysis for the estimation of species richness. The performance metrics used were taxonomic accuracy and agreement between the morphological and molecular species richness estimation. Clustering (at the 3% level) and GMYC reliably estimated species diversity for single or multiple geographic regions, with an error for larger clades of lower than 10%, thus outperforming parataxonomy. However, the rates of error were higher for some individual genera, with values of up to 45% when very recent species formed nonmonophyletic clusters. Taxonomic accuracy was always lower, with error rates above 20% and a larger variation at the genus level (0 to 70%). Sørensen similarity indices calculated for morphospecies, 3% clusters and GMYC entities for different pairs of localities was consistent among methods and showed expected decrease over distance. Cox1 sequence data are a powerful tool for large-scale species richness estimation, with a great potential for use in ecology and β-diversity studies and for setting conservation priorities. However, error rates can be high in individual lineages