An inquiry-based learning approach to teaching information retrieval

The study of information retrieval (IR) has increased in interest and importance with the explosive growth of online information in recent years. Learning about IR within formal courses of study enables users of search engines to use them more knowledgeably and effectively, while providing the starting point for the explorations of new researchers into novel search technologies. Although IR can be taught in a traditional manner of formal classroom instruction with students being led through the details of the subject and expected to reproduce this in assessment, the nature of IR as a topic makes it an ideal subject for inquiry-based learning approaches to teaching. In an inquiry-based learning approach students are introduced to the principles of a subject and then encouraged to develop their understanding by solving structured or open problems. Working through solutions in subsequent class discussions enables students to appreciate the availability of alternative solutions as proposed by their classmates. Following this approach students not only learn the details of IR techniques, but significantly, naturally learn to apply them in solution of problems. In doing this they not only gain an appreciation of alternative solutions to a problem, but also how to assess their relative strengths and weaknesses. Developing confidence and skills in problem solving enables student assessment to be structured around solution of problems. Thus students can be assessed on the basis of their understanding and ability to apply techniques, rather simply their skill at reciting facts. This has the additional benefit of encouraging general problem solving skills which can be of benefit in other subjects. This approach to teaching IR was successfully implemented in an undergraduate module where students were assessed in a written examination exploring their knowledge and understanding of the principles of IR and their ability to apply them to solving problems, and a written assignment based on developing an individual research proposal

Can agricultural cultivation methods influence the healthfulness of crops for foods

The aim of the current study was to investigate if there are any health effects of long-term consumption of organically grown crops using a rat model. Crops were retrieved over two years from along-term field trial at three different locations in Denmark, using three different cultivation systems(OA, organic based on livestock manure; OB, organic based on green manure; and C, conventional with mineral fertilizers and pesticides)with two field replicates. The cultivation system had an impact on the nutritional quality, affecting γ-tocopherol, some amino acids, and fatty acid composition. Additionally, the nutritional quality was affected by harvest year and location. However, harvest year and location rather than cultivation system affected the measured health biomarkers. In conclusion, the differences in dietary treatments composed of ingredients from different cultivation systems did not lead to significant differences in the measured health biomarkers, except for a significant difference in plasma IgGl evels

A critical reflection of current trends in discourse analytical research on leadership across disciplines. A call for a more engaging dialogue

This paper takes the frequently lamented state of current leadership research in business and organisational sciences as a starting point and argues for a more open and engaging dialogue with leadership researchers in applied linguistics and pragmatics. Focusing on current debates around terminological issues and methodological questions that are particularly prominent in critical leadership studies, we show that research in applied linguistics and pragmatics has the potential to make important contributions by providing the analytical tools and processes to support critical leadership researchers in their quest to challenge hegemonic notions of leadership by moving beyond simplistic and often problematic leader-follower dichotomies and by providing empirical evidence to capture leadership in situ thereby feeding into current theorisations of leadership

Surfactant status and respiratory outcome in premature infants receiving late surfactant treatment.

BACKGROUND:Many premature infants with respiratory failure are deficient in surfactant, but the relationship to occurrence of bronchopulmonary dysplasia (BPD) is uncertain. METHODS:Tracheal aspirates were collected from 209 treated and control infants enrolled at 7-14 days in the Trial of Late Surfactant. The content of phospholipid, surfactant protein B, and total protein were determined in large aggregate (active) surfactant. RESULTS:At 24 h, surfactant treatment transiently increased surfactant protein B content (70%, p < 0.01), but did not affect recovered airway surfactant or total protein/phospholipid. The level of recovered surfactant during dosing was directly associated with content of surfactant protein B (r = 0.50, p < 0.00001) and inversely related to total protein (r = 0.39, p < 0.0001). For all infants, occurrence of BPD was associated with lower levels of recovered large aggregate surfactant, higher protein content, and lower SP-B levels. Tracheal aspirates with lower amounts of recovered surfactant had an increased proportion of small vesicle (inactive) surfactant. CONCLUSIONS:We conclude that many intubated premature infants are deficient in active surfactant, in part due to increased intra-alveolar metabolism, low SP-B content, and protein inhibition, and that the severity of this deficit is predictive of BPD. Late surfactant treatment at the frequency used did not provide a sustained increase in airway surfactant

Perspectives on the ‘silent period’ for emergent bilinguals in England

This paper draws together the research findings from two ethnographic studies (Drury, 2007; Bligh, 2011) as a means to problematize the ‘silent period’ as experienced by young bilingual learners in two English speaking early years settings in England. Most teachers and senior early years practitioners in England are monolingual English speakers. The children (regardless of their mother tongue) are taught through the medium of spoken and written English in and through all subject areas. Bilingual learning through the mother tongue is not only disregarded in most schools in England but is actively discouraged in some. Three emergent bilingual learners were re-examined as case studies. Suki and Adyta (Bligh, 2011) of Japanese and Punjabi decent and Nazma (Drury, 2007) of Kashmiri descent were observed whilst they each negotiated new ways of knowing within and through an English pre-school setting. Sociocultural insights into how these young children employ their silenced mother tongue to negotiate their learning creates a fuller and richer portrait of the emergent bilingual learner both in and outside of preschool. These collaborative research findings present the silent period as agentive (Drury, 2007) and as a crucial time for self-mediated learning (Bligh, 2011) within the early years community of practice

Gd(III) complexes intercalated into hydroxy double salts as potential MRI contrast agents

The ion exchange intercalation of two Gd-based magnetic resonance imaging contrast agents into hydroxy double salts (HDSs) is reported. The presence of Gd3+ diethylenetriaminepentaacetate and Gd3+ diethylenetriaminepenta(methylenephosphonate) complexes in the HDS lattice after intercalation was confirmed by microwave plasma-atomic emission spectroscopy. The structural aspects of the HDS-Gd composites were studied by X-ray diffraction, with the intercalates having an interlayer spacing of 14.5–18.6 Å. Infrared spectroscopy confirmed the presence of characteristic vibration peaks associated with the Gd3+ complexes in the intercalation compounds. The proton relaxivities of the Gd3+ complex-loaded composites were 2 to 5-fold higher in longitudinal relaxivity, and up to 10-fold higher in transverse relaxivity, compared to solutions of the pure complexes. These data demonstrate that the new composites reported here are potentially potent MRI contrast agents

DISTRIBUTION AND PROPERTIES OF CDP-DIGLYCERIDE:INOSITOL TRANSFERASE FROM BRAIN 1

CDP-diglyceride is converted to phosphatidyl inositol by several particulate subcellular fractions of guinea pig brain, with highest specific activity in the microsomal fraction. Optimal conditions with respect to pH, metal ion concentration, and substrate concentrations have been determined. The reaction was stimulated by the addition of bovine serum albumin and by Tween 80. Of several dl-CDP-diglycerides synthesized and used as substrates in a spectrophoto-metric assay for the enzyme, dl-CDP-didecanoin was the most active. The enzyme showed a high selectivity for myo-inositol. Of a number of compounds tested, only scyllo -inosose and epi -inosose served as substrates. Three inositol isomers and three myo -inositol monophosphates inhibited the reaction slightly. The most potent inhibitor found was galactinol, a myo -inositol galactoside.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66197/1/j.1471-4159.1969.tb06850.x.pd

Isotopic evidences for microbiologically mediated and direct C input to soil compounds from three different leaf litters during their decomposition

We show the potentiality of coupling together different compound-specific isotopic analyses in a laboratory experiment, where 13C-depleted leaf litter was incubated on a 13C-enriched soil. The aim of our study was to identify the soil compounds where the C derived from three different litter species is retained. Three 13C-depleted leaf litter (Liquidambar styraciflua L., Cercis canadensis L. and Pinus taeda L., δ13CvsPDB ≈ −43‰), differing in their degradability, were incubated on a C4 soil (δ13CvsPDB ≈ −18‰) under laboratory-controlled conditions for 8 months. At harvest, compound-specific isotope analyses were performed on different classes of soil compounds [i.e. phospholipids fatty acids (PLFAs), n-alkanes and soil pyrolysis products]. Linoleic acid (PLFA 18:2ω6,9) was found to be very depleted in 13C (δ13CvsPDB ≈ from −38 to −42‰) compared to all other PLFAs (δ13CvsPDB ≈ from −14 to −35‰). Because of this, fungi were identified as the first among microbes to use the litter as source of C. Among n-alkanes, long-chain (C27–C31) n-alkanes were the only to have a depleted δ13C. This is an indication that not all of the C derived from litter in the soil was transformed by microbes. The depletion in 13C was also found in different classes of pyrolysis products, suggesting that the litter-derived C is incorporated in less or more chemically stable compounds, even only after 8 months decomposition

Low pH enhances the action of maximin H5 against Staphylococcus aureus and helps mediate lysylated phosphatidylglycerol induced resistance

Maximin H5 (MH5) is an amphibian antimicrobial peptide specifically targeting Staphylococcus aureus. At pH 6, the peptide showed an increased ability to penetrate (∆П = 6.2 mN m-1) and lyse (lysis = 48 %) S. aureus membrane mimics, which incorporated physiological levels of lysylated phosphatidylglycerol (Lys-PG, 60 %) as compared to pH 7 (∆П = 5.6 mN m-1 and lysis = 40 % at pH 7) where levels of Lys-PG are lower (40 %). The peptide therefore appears to have optimal function at pH levels known to be optimal for the organism’s growth. MH5 killed S. aureus (minimum inhibitory concentration = 90 µM) via membranolytic mechanisms that involved the stabilization of α-helical structure (circa 45-50 %) and which showed similarities to the ‘Carpet’ mechanism based on its ability to increase the rigidity (Cs-1 = 109.94 mN m-1) and thermodynamic stability (∆Gmix = -3.0) of physiologically relevant S. aureus membrane mimics at pH 6. Based on theoretical analysis this mechanism may involve the use of a tilted peptide structure and efficacy was noted to vary inversely with the Lys-PG content of S. aureus membrane mimics for each pH studied (R2 circa 0.97), which led to the suggestion that under biologically relevant conditions, low pH helps mediate Lys-PG induced resistance in S. aureus to MH5 antibacterial action. The peptide showed a lack of haemolytic activity (< 2 % haemolysis) and merits further investigation as a potential template for development as an anti-staphylococcal agent in medically and biotechnically relevant areas