Measures of Anxiety in Zebrafish (Danio rerio): Dissociation of Black/White Preference and Novel Tank Test

The effects of wall color stimuli on diving, and the effects of depth stimuli on scototaxis, were assessed in zebrafish. Three groups of fish were confined to a black, a white, or a transparent tank, and tested for depth preference. Two groups of fish were confined to a deep or a shallow tank, and tested for black-white preference. As predicted, fish preferred the deep half of a split-tank over the shallow half, and preferred the black half of a black/white tank over the white half. Results indicated that the tank wall color significantly affected depth preference, with the transparent tank producing the strongest depth preference and the black tank producing the weakest preference. Tank depth, however, did not significantly affect color preference. Additionally, wall color significantly affected shuttling and immobility, while depth significantly affected shuttling and thigmotaxis. These results are consistent with previous indications that the diving response and scototaxis may reflect dissociable mechanisms of behavior. We conclude that the two tests are complementary rather than interchangeable, and that further research on the motivational systems underlying behavior in each of the two tests is needed

Improved timber harvest techniques maintain biodiversity in tropical forests

Tropical forests are selectively logged at 20 times the rate at which they are cleared, and at least a fifth have already been disturbed in this way. In a recent pan-tropical assessment, Burivalova et al. demonstrate the importance of logging intensity as a driver of biodiversity decline in timber estates. Their analyses reveal that species richness of some taxa could decline by 50% at harvest intensities of 38 m3 ha-1. However, they did not consider the extraction techniques that lead to these intensities. Here, we conduct a complementary meta-analysis of assemblage responses to differing logging practices: conventional logging and reduced-impact logging. We show that biodiversity impacts are markedly less severe in forests that utilise reduced-impact logging, compared to those using conventional methods. While supporting the initial findings of Burivalova et al., we go on to demonstrate that best practice forestry techniques curtail the effects of timber extraction regardless of intensity. Therefore, harvest intensities are not always indicative of actual disturbance levels resulting from logging. Accordingly, forest managers and conservationists should advocate practices that offer reduced collateral damage through best practice extraction methods, such as those used in reduced-impact logging. Large-scale implementation of this approach would lead to improved conservation values in the 4 million km2 of tropical forests that are earmarked for timber extraction

Impact of electronic reminders on venous thromboprophylaxis after admissions and transfers

Objective Clinical decision support has the potential to improve prevention of venous thromboembolism (VTE). The purpose of this prospective study was to analyze the effect of electronic reminders on thromboprophylaxis rates in wards to which patients were admitted and transferred. The latter was of particular interest since patient handoffs are considered to be critical safety issues. Methods The trial involved two study periods in the six departments of a university hospital, three of which were randomly assigned to the intervention group displaying reminders during the second period. At 6 h after admission or transfer, the algorithm checked for prophylaxis orders within 0-30 h of the patient's arrival, increasing the specificity of the displayed reminders. Results The significant impact of the reminders could be seen by prophylaxis orders placed 6-24 h after admission (increasing from 8.6% (223/2579) to 12% (307/2555); p<0.0001) and transfer (increasing from 2.4% (39/1616) to 3.7% (63/1682); p=0.034). In admission wards, the rate of thromboprophylaxis increased from 62.4% to 67.7% (p<0.0001), and in transfer wards it increased from 80.2% to 84.3% (p=0.0022). Overall, the rate of prophylaxis significantly increased in the intervention group from 69.2% to 74.3% (p<0.0001). No significant changes were observed in the control group. Postponing prophylaxis checks to 6 h after admissions and transfers reduced the number of reminders by 62% and thereby minimized the risk of alert fatigue. Conclusions The reminders improved awareness of VTE prevention in both admission and transfer wards. This approach may contribute to better quality of care and safer patient handoff

Phenomenology of the Equivalence Principle with Light Scalars

Light scalar particles with couplings of sub-gravitational strength, which can generically be called 'dilatons', can produce violations of the equivalence principle. However, in order to understand experimental sensitivities one must know the coupling of these scalars to atomic systems. We report here on a study of the required couplings. We give a general Lagrangian with five independent dilaton parameters and calculate the "dilaton charge" of atomic systems for each of these. Two combinations are particularly important. One is due to the variations in the nuclear binding energy, with a sensitivity scaling with the atomic number as $A^{-1/3}$. The other is due to electromagnetism. We compare limits on the dilaton parameters from existing experiments.Comment: 5 page

Verb generation in children with spina bifida.

We investigated verb generation in children with spina bifida meningomyelocele (SBM; n = 55) and in typically developing controls (n = 32). Participants completed 6 blocks (40 trials each) of a task requiring them to produce a semantically related verb in response to a target noun and an additional 40 trials on which they were simply required to read target nouns aloud. After controlling for reading response time, groups did not differ significantly in verb generation response time or learning. Children with SBM produced more non-verb errors than controls and tended to repeat their mistakes over blocks. Verb generation performance was associated with brain volume measures in participants with SBM. Congenital cerebellar dysmorphology is associated with impaired performance in verb generation accuracy, although not with increased response times to produce verb

Efficient oxidative dearomatisations of substituted phenols using hypervalent iodine (iii) reagents and antiprotozoal evaluation of the resulting cyclohexadienones against T. b. rhodesiense and P. falciparum Strain NF54

Quinones and quinols are secondary metabolites of higher plants that are associated with many biological activities. The oxidative dearomatization of phenols induced by hypervalent iodine(III) reagents has proven to be a very useful synthetic approach for the preparation of these compounds, which are also widely used in organic synthesis and medicinal chemistry. Starting from several substituted phenols and naphthols, a series of cyclohexadienone and naphthoquinone derivatives were synthesized using different hypervalent iodine(III) reagents and evaluated for their in vitro antiprotozoal activity. Antiprotozoal activity was assessed against Plasmodium falciparum NF54 and Trypanosoma brucei rhodesiense STIB900. Cytotoxicity of all compounds towards L6 cells was evaluated and the respective selectivity indices (SI) were calculated. We found that benzyl naphthoquinone 5c was the most active and selective molecule against T. brucei rhodesiense (IC50 = 0.08 muM, SI = 275). Furthermore, the antiprotozoal assays revealed no specific effects. In addition, some key physicochemical parameters of the synthesised compounds were calculated

Dynamik der Stickstoffspezies im Boden und ihre Bedeutung für die Wurzelmorphologie - was haben wir von Drew gelernt?

Harnstoff ist nach Kalkammonsalpeter der bedeutendste Stickstoffdünger in Deutschland. Insbesondere in Kombination mit Nitrifikationsinhibitoren (NI) stellt Harnstoff eine Düngeform dar, die im Unterschied zu Ammoniumsulfat weniger zu einer Versauerung führt und gleichzeitig aufgrund der potentiellen Bindung des Zwischenproduktes Ammonium eine geringere Auswaschungsgefahr birgt als Nitratdünger. Die N-Düngeform beeinflusst neben pH-Wert und Mobilität auch die Morphologie/Physiologie des Wurzelsystems. Untersuchungen auf Gelplatten und in Nährlösung mit konstantem Angebot jeweils einer N-Spezies zeigen meist eine Förderung der Anzahl Seitenwurzeln bei reiner Ammoniumernährung und eine geringere Anzahl Seitenwurzeln bei Nitraternährung; die Länge der vorhandenen Seitenwurzeln ist tendenziell erhöht. Unklar ist, inwiefern solche Ergebnisse auf das System Pflanze Boden übertragbar sind. Im Boden stellt die organische Substanz stets eine zusätzliche N-Quelle dar. Aufgrund der mikrobiellen Aktivität liegen meist beide Stickstoffspezies zeitgleich vor. Am Austauscher bzw. in den Zwischenschichten von Tonmineralen wird NH4+ gebunden, welches sich im Gleichgewicht mit der Bodenlösung befindet. Es wurden Säulenversuche (h = 25 cm, Ø = 7 cm) mit Ackerbohne und Gerste mit homogenisiertem Unterboden einer Parabraunerde und plazierter Düngung von Harnstoff ohne und mit NI durchgeführt. Eine ungedüngte Kontrolle diente als Vergleich. Die Änderung der N-Spezies und des pH über die Zeit in zwei Bodentiefen wurde über Mikrosaugkerzen in situ erfasst. Die Änderung der Wurzelmorphologie über die Zeit mit Röntgentomographie (bei Ackerbohne) bzw. über destruktive Zwischenernten und WinRHIZO (bei Gerste) erfasst. Die Verwendung von Harnstoff mit NI führte zu einer Ausgangssituation in der NH4+ in der mineralischen Stickstofffraktion dominiert, allerdings nur im Nmin-Extrakt mit 1M KCl (gelöst + austauschbar gebunden) und nicht in der Bodenlösung. Diese Variante weist dann auch eine erhöhte Anzahl von Seitenwurzeln im Bereich der Plazierung auf – tendenziell bei Ackerbohne, signifikant bei Gerste. Weitaus prägnanter zeigt sich ein hemmender Effekt hoher Nitratkonzentrationen auf die Seitenwurzelbildung bei Gerste. Die in artifiziellen Systemen (Gelplatten, Nährlösungsversuche) gemachten Beobachtungen lassen sich prinzipiell auf das System Boden übertragen. Allerdings liegen die speziellen Randbedingungen im Boden selten und meist nur während kurzer Zeiträume vor