Confidence as a barrier to the use of problem-based learning in veterinary undergraduate students

Problem-based or case-based learning is a popular method of instruction in clinical degrees such as veterinary science, nursing, and medicine. It is difficult, however, for students to adapt to this learning method, and this difficulty has been well described. The present study surveyed first-year undergraduate veterinary students at the University of Nottingham about the challenges they faced upon beginning problem-based learning sessions. A surprisingly large percentage of students (36% of females and 38% of males) reported a lack of confidence in speaking in front of the other students as a concern they experienced during their first term. Conversely, only 10% of the female students (and none of the male students) reported overconfidence as a problem. This is in contrast to the perceptions of the staff members who facilitated the sessions who reported that 14% of the students exhibited underconfidence and 14% exhibited overconfidence. The difference between the female and male students' responses as well as the difference between the perceptions of students and those of facilitators is statistically significant (G-test p<.05).     

Clinical effect of buprenorphine or butorphanol,in combination with detomidine and diazepam,on sedation and postoperative pain after cheek tooth extraction in horses

The objective of this study was to compare effects of butorphanol (BUT) or buprenorphine (BUP), in combination with detomidine and diazepam, on the sedation quality, surgical conditions, and postoperative pain control after cheek tooth extraction in horses, randomly allocated to 2 treatment groups (BUT: n = 20; BUP: n = 20). A bolus of detomidine (15 μg/kg, IV) was followed by either BUP (7.5 μg/kg, IV) or BUT (0.05 mg/kg, IV). After 20 min, diazepam (0.01 mg/kg, IV) was administered and sedation was maintained with a detomidine IV infusion (20 μg/kg/h), with rate adjusted based on scores to 5 variables. All horses received a nerve block (maxillary or mandibular), and gingival infiltration with mepivacaine. Sedation quality was assessed by the surgeon from 1 (excellent) to 10 (surgery not feasible). A pain scoring system (EQUUS-FAP) was used to assess postoperative pain. Serum cortisol concentrations and locomotor activity (pedometers) were measured.Horses in BUP and BUT required a median detomidine infusion rate of 30.2 μg/kg/h (20 to 74.4 μg/kg/h) and 32.2 μg/kg/h (20 to 48.1 μg/kg/h), respectively (P = 0.22). Horses in the BUP group had better sedation quality (P < 0.05) during surgery and higher step counts (P < 0.001) postoperatively. Buprenorphine combined with detomidine provided a more reliable sedation than butorphanol. However, the EQUUS-FAP pain scale became unreliable because of BUP-induced excitement behavior.     

Placebo-controlled blinded study of postoperative pain therapy with carprofen and levomethadone in dogs with fractures

It was the aim of this placebo-controlled study to evaluate the analgesic efficacy of the NASAID carprofen and the pure m-agonist levomthadone over a five-day postoperative evaluation period in dogs with fractures of the humerus or the femur (n = 30). Pain and sedation evaluation was carried out with a visual analogues system (VAS) and with the aid of a numerical estimation scale(NRS). The degree of lameness, the pain treshhold, the glucose and cortisol concentration curves as well as the respiration and heart rate and the systolic blood pressure were used as further pain indicators and to identify drug side effects. The levomethadon group displayed the lowest degree of pain on postoperative examination on the first day. On days 2 to 5, the carprofen group showed the lowest degree of pain in comparison to the placebo group. The levomethadon- and the carprofen group showed no statistically proven differences from day 2 on. Due to great variations in the pain scores and comparatively high median pain score especially on the first day of this study, the efficacy of all analgesics evaluated here must be regarded as insufficient in many cases. Only the parameter nociceptive pain treshhold showed a little, the degree of lameness, the glucose and cortisol levels showed no close correlation to the VAS and NRS pain scores and were therefore of little usefulness as postoperative pain indicators. No relevant clinical side effects caused by the used analgesics were detected in the kidney, the liver, the gastrointestinal tract and the circulatory system in this study. Rather, traumatically induced elevation of enzyme levels improves or normalised until the 5th day of the study. In addition, no negative effect on wound healing was noted, especially for carprofen. Therefore, the evaluated analgesics seems to be adequate for postoperative pain therapy also in fracture patients (trauma patients). However, the efficacy of all analgesics evaluated here must be regarded as insufficient in many cases.     

Gap dynamics in a near-natural spruce forest at Mt. Brocken,Germany

We analyzed indices of gap dynamics, i.e. gap formation and gap closure rates as well as turnover rates, in a montane conifer forest in the temperate zone and asked: (1) Are the characteristics of gap dynamics comparable with those of other temperate forests? (2) Do gap dynamics exhibit temporal trends, and (3) if so, are they related to recent climate change? We also addressed methodological issues concerning the differences observed at differing temporal and spatial scales of the used datasets. Thus, we asked further how the indices of gap dynamics are influenced (4) by differences in the length of observation periods and (5) by differences in gap size categories included in the study?     

Rapid measurements of fat content in live and slaughtered common carp (<Emphasis Type="Italic">Cyprinus carpio</Emphasis> L.)

The objective of this study on common carp (Cyprinus carpio) was to obtain and predict the first cross-validated data of the fat content on market size carps using a non-invasive or non-destructive method in situ. The carps (1680 ± 388 g; n = 136) used were from a semi-intensive system and were on a different diet (cereal, pelleted and extruded diet). For the evaluation of the fat content, a Fish Fatmeter FM 692 from Distell.com. (FFM) and a manual measurement of back fat height using a digital calliper were used. For the prediction model, the following basic body measurements (variables) were used: total body length, body length, body height, the width of the body, and the circuit of the body. The body weight, weight of intestines, weight of gonads, weight of hepatopancreas, and fillet yield (%) were measured, and the Fulton coefficient was calculated. The study was focussed on evaluating the applicability of these methods and the accuracy of the obtained result, respectively. Results showed that all the rapid methods had a strong correlation. Multiple regression models with forward selection of variables were used throughout. The final prediction model between predicted and observed values for the fat content for FFM and calliper being adjusted index of determination is shown here (R _adj ²  = 0.88; 5 variables and R _adj ²  = 0.91; 7 variables), respectively.     

From wine to pepper: rotundone, an obscure sesquiterpene, is a potent spicy aroma compound

An obscure sesquiterpene, rotundone, has been identified as a hitherto unrecognized important aroma impact compound with a strong spicy, peppercorn aroma. Excellent correlations were observed between the concentration of rotundone and the mean 'black pepper' aroma intensity rated by sensory panels for both grape and wine samples, indicating that rotundone is a major contributor to peppery characters in Shiraz grapes and wine (and to a lesser extent in wine of other varieties). Approximately 80% of a sensory panel were very sensitive to the aroma of rotundone (aroma detection threshold levels of 16 ng/L in red wine and 8 ng/L in water). Above these concentrations, these panelists described the spiked samples as more 'peppery' and 'spicy'. However, approximately 20% of panelists could not detect this compound at the highest concentration tested (4000 ng/L), even in water. Thus, the sensory experiences of two consumers enjoying the same glass of Shiraz wine might be very different. Rotundone was found in much higher amounts in other common herbs and spices, especially black and white peppercorns, where it was present at approximately 10000 times the level found in very 'peppery' wine. Rotundone is the first compound found in black or white peppercorns that has a distinctive peppery aroma. Rotundone has an odor activity value in pepper on the order of 50000-250000 and is, on this criterion, by far the most powerful aroma compound yet found in that most important spice.     

The impact of extraction methodologies on the toxicity of sediments in the zebrafish (Danio rerio) embryo test

Purpose

Traditionally, methods for sediment extractions are characterised using chemical analyses. However, in order to evaluate sediment extracts with regard to biological effects and, thus, bioaccessibility, extraction methods have to be compared to effect data obtained from experiments with in situ exposure scenarios, i.e., sediment contact tests. This study compares four extraction methods and sediment contact test data from a previous project with respect to predictive power in the fish embryo test with zebrafish (Danio rerio).

Materials and methods

A natural and an artificial sediment spiked with a mixture of six organic pollutants (2,4-dinitrophenol, diuron, fluoranthene, nonylphenol, parathion and pentachlorophenol) were extracted using (a) membrane dialysis extraction (MDE), (b) a Soxhlet procedure, (c) hydroxypropyl-??-cyclodextrin (HPCD) or (d) Tenax^®-TA. Whereas the former two are regarded being exhaustive with respect to non-covalently bound contaminants, the latter two are considered to predict bioaccessibility. Resulting extracts were tested in the fish embryo assay with D. rerio for embryotoxic and teratogenic potential.

Results and discussion

Mortalities caused by organic extracts from Soxhlet extraction and MDE were high. However, HPCD extracts turned out to be at least as effective as extracts obtained with these two methods. One possible reason might be short ageing time of the spiked sediments. Only Tenax^®-TA extracts gave results comparable to the sediment contact assay for natural sediment, but revealed low reproducibility. Significant differences between natural and artificial sediment were found for extracts obtained with techniques using native (i.e., non-freeze-dried) sediments, i.e., HPCD and Tenax^®-TA. In contrast, MDE and Soxhlet extracts used freeze-dried sediment and did not differentiate between natural and artificial sediment. Therefore, freeze-drying has likely altered and equalised sediment properties that influence accessibility, such as composition of bacterial communities and organic matter quality.

Conclusions

Four extraction methods were successfully characterised with respect to their stringency and predictiveness for bioaccessibility. MDE was confirmed as an alternative to Soxhlet extraction. High mortalities induced by HPCD extracts underline the need to include ageing into consideration when assessing sediments. Although Tenax^®-TA may basically be used to predict bioaccessibility in the fish embryo test, the high variability observed warrants further investigation of the relation between effect and extractability. Apparently, freeze-drying can severely affect sediment properties, potentially eliminating individual properties of natural sediments.     

Digital image analysis of radial shrinkage of fresh spruce (Picea abies L.) wood

Contact-free digital image analysis was performed of the radial shrinkage of fresh, fully saturated small spruce wood beams. An experimental test set-up was developed to ensure constant distance from the charge-coupled device camera to the sample surface as well as constant climate and light conditions during the whole experiment. Dimensional changes were observed immediately after the drying process began. An unexpected distinct effect could be observed which could not be explained by drying surface layers only. After a fast initial radial shrinkage a slowing down of the dimensional changes occurred at high mean moisture contents. A complete interruption of any dimensional changes followed. Finally, a recovery from shrinkage was even observed. It is assumed that strong negative pressure occurred in the fully saturated capillaries owing to dehydration which led to additional dimensional changes. As a consequence, the break of the water column and aeration in these capillaries finally resulted in a recovery period in the shrinkage rate due to the pressure release. After this effect, the dehydration was characterized by a phase of fast and almost linear shrinkage due to drying surface layers. Finally, the shrinkage slowed down to zero when reaching equilibrium moisture content.     

Tree establishment and management on farms in the drylands: evaluation of different systems adopted by small-scale farmers in Mutomo District,Kenya

Agroforestry systems in Sub-Saharan African drylands are complex and heterogeneous in nature even under similar biophysical conditions. This can be attributed to household needs and socioeconomic status which influence the species and utility of the adopted trees. This has an impact on the trees establishment and management system through planting or Farmer Managed Natural Regeneration (FMNR). This study evaluates how trees for different utilities are managed and which socioeconomic factors influence these decisions. The study used primary data collected in Mutomo District, Kenya through a household survey based on a structured questionnaire. A paired sample t-test was done to assess the preferred mode of adopting trees for different utilities while factor analysis was used to characterize the households as either planting trees or practicing FMNR. Multiple linear regression using household regression factor scores as independent variables and socioeconomic indicators as dependent variables was done to ascertain which socioeconomic factors affect tree adoption. The results show that trees planted were mostly exotic species valued for their nutrition and commercial value, while FMNR was used for subsistence products and environmental services. Household size, livestock levels and mobility had a positive correlation with tree planting, while income, access to markets and roads had an inverse correlation. Access to natural woodland, distance to the nearest motorable road and land size had a positive correlation with tree protection. It is hoped that this knowledge will act as a reference point when designing agroforestry projects in similar areas to ensure they are more aligned to specific site and household conditions.