Macgyvers, Medeas, and Bionic Women: Patterns of Instructor Response to Negative Feedback

Few studies have examined instructor responses to negative feedback and their interplay with gender, but faculty developers must be cognizant of and sensitive to the needs of the instructors with whom they work. This chapter identifies six general patterns of response among male and female instructors to negative feedback from students and consultants, based on survey results, interviews, and observations. A combination of empathy, resources, and time is the key to understanding and responding to those patterns and meeting the needs of individual instructors. Further, comparisons across gender reveal interesting differences related to language use, internalization versus externalization of feedback, and holistic versus specific approaches to reflective teaching

Anti-nociceptive and antioxidant activities of an aqueous leaf extract of Corchorus olitorius L. (Tiliaceae)

A preliminary study had shown that C. olitorius has analgesic activity possibly mediated through opioidergic pathway. The study was a follow up work to evaluate the anti-nociceptive effects and other possible mechanisms of action of an aqueous leaf extract of C. olitorius (COE) using formalin-induced nociception test. COE was screened for its analgesic, and antioxidant activities. The anti-nociceptive effect of COE (3x10-2, 1x10-1 and 3x10-1 g kg-1, p.o), and morphine (1x10-3, 3x10-3 and 1x10-2 gkg-1, i.p.) were evaluated using the formalin-induced nociception test. The study showed that C. olitorius has analgesic activity possibly mediated through opioidergic pathway. COE produced significant (P ˂ 0.05) dose-dependent antinociceptive effects similar to morphine in both phases of formalin-induced nociception. The extract showed free radical scavenging properties and different phyto-constituents such as alkaloids, flavonoids, saponins, cardiac glycosides, tannins, anthraquinones and terpenoids were identified. COE has both central and peripheral anti-nociceptive effects mediated through opioidergic receptor activation and also partly through ATP-sensitive K+ channel activation systems. The findings confirms earlier reports, and further shows that C. olitorius produces anti-nociception by interrupting many pain processing pathways. Results further suggest that the extract (COE) might possess some chemical constituents that are responsible for the analgesic and the antioxidant activities.Keywords: Naloxone, glibenclamide, morphine, nociception, DPPH, formalin test

Multiple Linear Regression Model for Estimating the Price of a Housing Unit

This paper uses the respective unit costs, over fifteen (15) years, of selected Housing Unit Major Components (HUMC): cement, iron rods, aluzinc roofing sheets, coral paint, wood and sand, to develop Multiple Linear Regression Model (MLRM) for determining Housing Unit Price (HUP) for one-bedroom and two-bedroom housing units. In the modeling, the Ordinary Least Squares (OLS) normality assumption which could introduce errors in the statistical analyses was dealt with by log transformation of the data, ensuring the data is normally distributed and there is no correlation between them. Minimisation of Sum of Squares Error method was used to derive the model coefficients. The resultant MLRM is:  Ŷi MLRM = (X'X)-1 X'Y(xi') where X is the sample data matrix. The specific model for one-bedroom housing unit is loge (HUPMLRM)1-Bed = 1.017 – 2.225 x 10-5 x CC + 2.512 x 10-6 x CS + 6.016 x 10-4 x CIR  +  1.985 x  10-4 x CR + 5.694 x 10-4 x CP -7.437 x 10-4 x CW and that for two-bedroom housing unit is loge (HUPMLRM)2-Bed = 5.760 – 7.501 x 10-7 x CC + 2.935 x 10-6 x CS + 1.898 x 10-3 x CIR  +  6.695 x 10-4 x CR - 9.157 x 10-3 x CP +6.136 x 10-3 x CW, where CC, CS, CIR, CR, CP and CW are costs of the total quantity of cement, sand, iron rods, roofing, paint and wood respectively. The MLRM was validated by using it to estimate the known HUP in the 15.5th year. From the results, the percentage absolute deviations of the estimated HUP from the known HUP are 1.27% and 2.02% for one-bedroom and two-bedroom housing units respectively, which are satisfactory. The novel approach presented in this paper is a valuable contribution to the body of knowledge in modeling. Keywords: Multiple Regression Analysis, Housing Unit Major Components, Housing Unit Pric

Identical temperature dependence of the time scales of several linear-response functions of two glass-forming liquids

The frequency-dependent dielectric constant, shear and adiabatic bulk moduli, longitudinal thermal expansion coefficient, and longitudinal specific heat have been measured for two van der Waals glass-forming liquids, tetramethyl-tetraphenyl-trisiloxane (DC704) and 5-polyphenyl-4-ether. Within the experimental uncertainties the loss-peak frequencies of the measured response functions have identical temperature dependence over a range of temperatures, for which the Maxwell relaxation time varies more than nine orders of magnitude. The time scales are ordered from fastest to slowest as follows: Shear modulus, adiabatic bulk modulus, dielectric constant, longitudinal thermal expansion coefficient, longitudinal specific heat. The ordering is discussed in light of the recent conjecture that van der Waals liquids are strongly correlating, i.e., approximate single-parameter liquids.Comment: 8 pages, 6 figures, Substantially revised versio

Schistosoma haematobium co-infection with soil-transmitted helminthes: prevalence and risk factors from two communities in the central region of Ghana

Background: Schistosoma haematobium co-infection with S. mansoni and  soil-transmitted helminthes afflict most-at-risk populations in endemic communities in the developing world. Aim: This study investigated S. haematobium co-infection with soil-transmitted helminthes, and host risk factors in two communities in the central region of Ghana. Methods: Schools and children were selected by stratified cluster and random sampling methods respectively. A total of 250 school children (aged 5 - > 20 years) were recruited. Teachers issued questionnaires to obtain information on host risk factors, water-contact activities and knowledge of S.  haematobium infection. Urine and stool samples were examined for S. haematobium infection and S. mansoni and soil-transmitted helminthes using sedimentation quantitative and direct smear/formol-ether sedimentation concentration techniques respectively.Results: S. haematobium infection (1 - 50 eggs/10 ml urine)  prevalence at Apewosika and Putubiw were 27.5 % and 17 % respectively. Males were more at risk of S. haematobium infection than females. S. haematobium co-infection with soil-transmitted helminthes (A. lumbricoides, E. histolytica, and T. trichuria) was recorded in Putubiw, with females more at risk than males. Children aged 16-19 and 10-15 were more at risk of S. haematobium infection and  helminthic co-infection respectively. Haematuria and proteinuria were predictive of S. haematobium infection. School children had poor knowledge of S. haematobium infection. Water-contact activity was common.Conclusion: S. haematobium prevalence and its co-infection with soil-transmitted helminthes were common in Putubiw. Watercontact activity and poor knowledge about S. haematobium infection were major risk factors. Increased education on preventive and control measures especially in schools is recommended.Key words: Haematuria, proteinuria, Schistosoma haematobium, S. mansoni, helminthes, Bulinus globosu

Evidence for the evolutionary steps leading to mecA-mediated ß-lactam resistance in staphylococci

The epidemiologically most important mechanism of antibiotic resistance in Staphylococcus aureus is associated with mecA–an acquired gene encoding an extra penicillin-binding protein (PBP2a) with low affinity to virtually all β-lactams. The introduction of mecA into the S. aureus chromosome has led to the emergence of methicillin-resistant S. aureus (MRSA) pandemics, responsible for high rates of mortality worldwide. Nonetheless, little is known regarding the origin and evolution of mecA. Different mecA homologues have been identified in species belonging to the Staphylococcus sciuri group representing the most primitive staphylococci. In this study we aimed to identify evolutionary steps linking these mecA precursors to the β-lactam resistance gene mecA and the resistance phenotype. We sequenced genomes of 106 S. sciuri, S. vitulinus and S. fleurettii strains and determined their oxacillin susceptibility profiles. Single-nucleotide polymorphism (SNP) analysis of the core genome was performed to assess the genetic relatedness of the isolates. Phylogenetic analysis of the mecA gene homologues and promoters was achieved through nucleotide/amino acid sequence alignments and mutation rates were estimated using a Bayesian analysis. Furthermore, the predicted structure of mecA homologue-encoded PBPs of oxacillin-susceptible and -resistant strains were compared. We showed for the first time that oxacillin resistance in the S. sciuri group has emerged multiple times and by a variety of different mechanisms. Development of resistance occurred through several steps including structural diversification of the non-binding domain of native PBPs; changes in the promoters of mecA homologues; acquisition of SCCmec and adaptation of the bacterial genetic background. Moreover, our results suggest that it was exposure to β-lactams in human-created environments that has driven evolution of native PBPs towards a resistance determinant. The evolution of β-lactam resistance in staphylococci highlights the numerous resources available to bacteria to adapt to the selective pressure of antibiotics

Distributions of dissolved trace metals (Cd, Cu, Mn, Pb, Ag) in the southeastern Atlantic and the Southern Ocean

International audienceComprehensive synoptic datasets (surface water down to 4000 m) of dissolved cadmium (Cd), copper (Cu), manganese (Mn), lead (Pb) and silver (Ag) are presented along a section between 34° S and 57° S in the southeastern Atlantic Ocean and the Southern Ocean to the south off South Africa. The vertical distributions of Cu and Ag display nutrient-like profiles similar to silicic acid, and of Cd similar to phosphate. The distribution of Mn shows a subsurface maximum in the oxygen minimum zone, whereas Pb concentrations are rather invariable with depth. Dry deposition of aerosols is thought to be an important source of Pb to surface waters close to South Africa, and dry deposition and snowfall may have been significant sources of Cu and Mn at the higher latitudes. Furthermore, the advection of water masses enriched in trace metals following contact with continental margins appeared to be an important source of trace elements to the surface, intermediate and deep waters in the southeastern Atlantic Ocean and the Antarctic Circumpolar Current. Hydrothermal inputs may have formed a source of trace metals to the deep waters over the Bouvet Triple Junction ridge crest, as suggested by relatively enhanced dissolved Mn concentrations. The biological utilization of Cu and Ag was proportional to that of silicic acid across the section, suggesting that diatoms formed an important control over the removal of Cu and Ag from surface waters. However, uptake by dino- and nano-flagellates may have influenced the distribution of Cu and Ag in the surface waters of the subtropical Atlantic domain. Cadmium correlated strongly with phosphate (P), yielding lower Cd / P ratios in the subtropical surface waters where phosphate concentrations were below 0.95 μM. The greater depletion of Cd relative to P observed in the Weddell Gyre compared to the Antarctic Circumpolar Current could be due to increase Cd uptake induced by iron-limiting conditions in these high-nutrient-low-chlorophyll waters. Similarly, an increase of Mn uptake under Fe-depleted conditions may have caused the highest depletion of Mn relative to P in the surface waters of the Weddell Gyre. In addition, a cellular Mn-transport channel of Cd was possibly activated in the Weddell Gyre, which in turn may have yielded depletion of both Mn and Cd in these surface waters

Targeted gene delivery to the enteric nervous system using AAV: a comparison across serotypes and capsid mutants

Recombinant adeno-associated virus (AAV) vectors are one of the most widely used gene transfer systems in research and clinical trials. AAV can transduce a wide range of biological tissues, however to date, there has been no investigation on targeted AAV transduction of the enteric nervous system (ENS). Here, we examined the efficiency, tropism, spread, and immunogenicity of AAV transduction in the ENS. Rats received direct injections of various AAV serotypes expressing green fluorescent protein (GFP) into the descending colon. AAV serotypes tested included; AAV 1, 2, 5, 6, 8, or 9 and the AAV2 and AAV8 capsid mutants, AAV2-Y444F, AAV2-tripleY-F, AAV2-tripleY-F+T-V, AAV8-Y733F, and AAV8-doubeY-F+T-V. Transduction, as determined by GFP-positive cells, occurred in neurons and enteric glia within the myenteric and submucosal plexuses of the ENS. AAV6 and AAV9 showed the highest levels of transduction within the ENS. Transduction efficiency scaled with titer and time, was translated to the murine ENS, and produced no vector-related immune response. A single injection of AAV into the colon covered an area of ~47 mm(2). AAV9 primarily transduced neurons, while AAV6 transduced enteric glia and neurons. This is the first report on targeted AAV transduction of neurons and glia in the ENS

Minimal model for beta relaxation in viscous liquids

Contrasts between beta relaxation in equilibrium viscous liquids and glasses are rationalized in terms of a double-well potential model with structure-dependent asymmetry, assuming structure is described by a single order parameter. The model is tested for tripropylene glycol where it accounts for the hysteresis of the dielectric beta loss peak frequency and magnitude during cooling and reheating through the glass transition.Comment: Phys. Rev. Lett. (in press