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Summary: The plant hormone ethylene is of vital importance in the regulation of plant development and stress responses. Recent studies revealed that 1‐aminocyclopropane‐1‐carboxylic acid (ACC) plays a role beyond its function as an ethylene precursor. However, the absence of reliable methods to quantify ACC and its conjugates malonyl‐ACC (MACC), glutamyl‐ACC (GACC), and jasmonyl‐ACC (JA‐ACC) hinders related research.Combining synthetic and analytical chemistry, we present the first, validated methodology to rapidly extract and quantify ACC and its conjugates using ultra‐high‐performance liquid chromatography coupled to tandem mass spectrometry (UPLC‐MS/MS). Its relevance was confirmed by application to Arabidopsis mutants with altered ACC metabolism and wild‐type plants under stress.Pharmacological and genetic suppression of ACC synthesis resulted in decreased ACC and MACC content, whereas induction led to elevated levels. Salt, wounding, and submergence stress enhanced ACC and MACC production. GACC and JA‐ACC were undetectable in vivo; however, GACC was identified in vitro, underscoring the broad applicability of the method.This method provides an efficient tool to study individual functions of ACC and its conjugates, paving the road toward exploration of novel avenues in ACC and ethylene metabolism, and revisiting ethylene literature in view of the recent discovery of an ethylene‐independent role of ACC. [ABSTRACT FROM AUTHOR]

Growth hormone (GH) is fundamental for growth and glucose homeostasis, and prolactin for optimal pregnancy and lactation outcome, but additionally, both hormones have multiple functions that include a strong impact on energetic metabolism. In this respect, prolactin and GH receptors have been found in brown, and white adipocytes, as well as in hypothalamic centers regulating thermogenesis. This review describes the neuroendocrine control of the function and plasticity of brown and beige adipocytes, with a special focus on prolactin and GH actions. Most evidence points to a negative association between high prolactin levels and the thermogenic capacity of BAT, except in early development. During lactation and pregnancy, prolactin may be a contributing factor that limits unneeded thermogenesis, downregulating BAT UCP1. Furthermore, animal models of high serum prolactin have low BAT UCP1 levels and whitening of the tissue, while lack of Prlr induces beiging in WAT depots. These actions may involve hypothalamic nuclei, particularly the DMN, POA and ARN, brain centers that participate in thermogenesis. Studies on GH regulation of BAT function present some controversies. Most mouse models with GH excess or deficiency point to an inhibitory role of GH on BAT function. Even so, a stimulatory role of GH on WAT beiging has also been described, in accordance with whole‐genome microarrays that demonstrate divergent response signatures of BAT and WAT genes to the loss of GH signaling. Understanding the physiology of BAT and WAT beiging may contribute to the ongoing efforts to curtail obesity. [ABSTRACT FROM AUTHOR]

Vinylogous urethane (VUO) based polymer networks are widely used as catalyst‐free vitrimers that show rapid covalent bond exchange at elevated temperatures. In solution, vinylogous ureas (VUN) undergo much faster bond exchange than VUO and are highly dynamic at room temperature. However, this difference in reactivity is not observed in their respective dynamic polymer networks, as VUO and VUN vitrimers prepared herein with very similar macromolecular architectures show comparable stress relaxation and creep behavior. However, by using mixtures of VUO and VUN linkages within the same network, the dynamic reactions can be accelerated by an order of magnitude. The results can be rationalized by the effect of intermolecular hydrogen bonding, which is absent in VUO vitrimers, but is very pronounced for vinylogous urea moieties. At low concentrations of VUN, these hydrogen bonds act as catalysts for covalent bond exchange, while at high concentration, they provide a pervasive vinylogous urea ‐ urethane (VU) network of strong non‐covalent interactions, giving rise to phase separation and inhibiting polymer chain dynamics. This offers a straightforward design principle for dynamic polymer materials, showing at the same time the possible additive and synergistic effects of supramolecular and dynamic covalent polymer networks. [ABSTRACT FROM AUTHOR]

Homologous recombination (HR) is a key DNA damage repair pathway that is tightly adjusted to the state of a cell. A central regulator of homologous recombination is the conserved helicase‐containing Bloom syndrome complex, renowned for its crucial role in maintaining genome integrity. Here, we show that in Arabidopsis thaliana, Bloom complex activity is controlled by selective autophagy. We find that the recently identified DNA damage regulator KNO1 facilitates K63‐linked ubiquitination of RMI1, a structural component of the complex, thereby triggering RMI1 autophagic degradation and resulting in increased homologous recombination. Conversely, reduced autophagic activity makes plants hypersensitive to DNA damage. KNO1 itself is also controlled at the level of proteolysis, in this case mediated by the ubiquitin–proteasome system, becoming stabilized upon DNA damage via two redundantly acting deubiquitinases, UBP12 and UBP13. These findings uncover a regulatory cascade of selective and interconnected protein degradation steps resulting in a fine‐tuned HR response upon DNA damage. Synopsis: KNOTEN1 (KNO1) is a recently identified RBR1 transcriptional target involved in the DNA damage response in Arabidopsis thaliana. Functional characterization of KNO1 reveals it as a regulator of homologous recombination repair via damage‐dependent degradation of the core Bloom syndrome complex component RMI1.KNO1 mediates K63‐linked ubiquitination of RMI1 to trigger its degradation via autophagyAutophagic degradation of RMI1 facilitates homologous recombination after DNA damage.In the absence of DNA damage, KNO1 is constitutively degraded via the ubiquitin–proteasome pathway.KNO1 becomes stabilized after DNA damage via de‐ubiquitination by UBP12 and UBP13.Reduced autophagy sensitizes plants to DNA damage. [ABSTRACT FROM AUTHOR]

Dynamic covalent polymer networks provide an interesting solution to the challenging recyclability of thermosets and elastomers. One of the remaining design constraints, however, is balancing thermal reprocessability in the form of material flow with dimensional stability during use. As a result, many chemistries are being investigated in order to improve bond reactivity control and material robustness. This Minireview highlights a number of promising concepts, with a particular emphasis on disconnecting chemical reactivity in low and high temperature regimes to obtain creep resistant, yet highly dynamic polymer networks. In addition, we will highlight the impact of sharp reactivity changes when applying extrapolation‐based approaches during rheological analysis. As a result, we are confident that abandoning the myth of "permanent" reactivity will aid in the development of sustainable polymeric materials that can truly combine the benefits of thermoplastic and thermoset behaviour. [ABSTRACT FROM AUTHOR]

Background: Guidance during inquiry learning plays an important role in developing conceptual understanding and inquiry skills. This study analysed learner‐tutor interactions in a simulation‐assisted learning environment to investigate how tutor guidance enabled knowledge construction and fostered epistemic practice. Objectives: This research aimed to illuminate challenges learners encounter in the inquiry process and forms of guidance that support learning in both conceptual and epistemic aspects. Methods: This study uses a mixed methods approach. We analysed video recordings in which nine participants asked 72 questions and the microsequences of interactions immediately surrounding and including each question. We coded properties of each question and whether the tutors' utterances were intended to increase (upregulate) or decrease (downregulate) the complexity of the inquiry processes, and used a two‐step cluster analysis to explore groupings emerged from tutors' regulation guidance and learners' questions. Results and Conclusions: The regulatory intent of tutors' utterances depended on various characteristics of student questions. The microsequences clustered in five categories: 1) upregulated investigation and inference, 2) upregulated evidence‐based justification, 3) downregulated cognitive load, 4) downregulated procedural uncertainties, and 5) downregulated perceptual dissonance. Our findings suggest tutors offering guiding prompts should consider dual processes in the inquiry and, by strategically prompting them, strike a balance between the goals of guiding learners to discover scientific knowledge and grounding their conceptual understanding in concepts, data, and procedures. Implications: We emphasize conceptual and epistemic learning should be concurrently guided in scientific inquiry. We propose a bidirectional guidance model as a pedagogical approach to guide instructional practice. Lay Description: What is currently known about the subject matter: Rapid technological change urges schools to equip students with research and inquiry skills.Computer simulations provide an information‐rich environment for inquiry‐based learning.Guidance in inquiry learning is important for knowledge acquisition and the development of inquiry skills. What this paper adds: We illuminated challenges learners encounter in the inquiry learning process.We analysed forms of guidance that support learning in both conceptual and epistemic aspects.We identified dual processes involved in the inquiry process that have important implications.We proposed a bidirectional model for adaptive guidance in scientific inquiry. Implications of study findings for practitioners: Adaptive guidance facilitates conceptual and epistemic understanding by stimulating curiosity and reducing uncertainty in the inquiry process.Conceptual and epistemic learning need to be concurrently guided in scientific inquiry. [ABSTRACT FROM AUTHOR]

Background: The clinical benefit of cusatuzumab, a CD70‐directed monoclonal antibody with enhanced effector functions, was investigated in patients with relapsed/refractory (R/R) cutaneous T‐cell lymphoma (CTCL). Methods: In this cohort expansion of the ARGX‐110‐1201 study, 27 patients with R/R CTCL received cusatuzumab at 1 (n = 11) or 5 mg/kg (n = 16) once every 3 weeks to investigate its safety, dose, and exploratory efficacy. The pharmacokinetics, immunogenicity, CD70 expression, and CD70/CD27 biology were also assessed. Results: The most common adverse events included infusion‐related reactions, pyrexia, and asthenia. Eighteen serious adverse events (grade 1‐3) were reported in 11 patients; 1 of these (vasculitis) was considered drug‐related. For 8 of the 11 patients receiving 1 mg/kg, anti‐drug antibodies (ADAs) affected the minimal concentration, and this resulted in undetectable cusatuzumab concentrations at the end of treatment and, in some cases, a loss of response. This effect was greatly reduced in the patients receiving 5 mg/kg. The overall response rate was 23%; this included 1 complete response and 5 partial responses (PRs) in 26 of the 27 evaluable patients. In addition, 9 patients achieved stable disease. The mean duration on cusatuzumab was 5.2 months, and the median duration was 2.5 months. Patients with Sézary syndrome (SS) achieved a 60% PR rate with a dosage of 5 mg/kg and a 33% PR rate with a dosage of 1 mg/kg; this resulted in an overall response rate of 50% for patients with SS at both doses. Conclusions: Cusatuzumab was well tolerated, and antitumor activity was observed at both 1 and 5 mg/kg in highly pretreated patients with R/R CTCL. The observed dose‐dependent effect on exposure supports the use of 5 mg/kg for future development. Cusatuzumab, a monoclonal antibody targeting CD70, is well tolerated and shows dose‐dependent evidence of antitumor activity in a heavily pretreated patient population with cutaneous T‐cell lymphoma. The overall response rate was 23% with increased efficacy in patients with Sézary syndrome, warranting further clinical development. [ABSTRACT FROM AUTHOR]

We report a straightforward chemical strategy to tackle current challenges of irreversible deformation in low Tg vitrimers at operating temperature. In particular, vinylogous urethane (VU) vitrimers were prepared where reactive free amines, necessary for material flow, were temporarily shielded inside the network backbone, by adding a small amount of dibasic ester to the curing mixture. The amines could be released as reactive chain ends from the resulting dicarboxamide bonds via thermally reversible cyclisation to an imide moiety. Indeed, (re)generation of the required nucleophilic amines as network defects ensured reprocessing and rapid material flow at higher temperature, where exchange dynamics are (re)activated. As a result, VU vitrimers were obtained with limited creep at service temperature, yet with good reprocessability at elevated temperatures. Thus, by exerting strong control on the molecular level over the availability of exchangeable functional groups, a remarkable improvement of VU properties was obtained. [ABSTRACT FROM AUTHOR]

Summary: Barrel‐ageing of conventionally fermented beers is becoming increasingly popular in recent years, but only very little is known about the underlying process. In this study, we show that wood species significantly affects the bacterial community composition, beer chemistry and sensory characteristics throughout 38 weeks of barrel‐ageing. Whereas the microbial communities of oak‐ and acacia‐aged beer became dominated by Pediococcus damnosus and Brettanomyces bruxellensis, beer aged in oak barrels also contained a large fraction of Acetobacter sp. (29.34%) and to a lesser extent Paenibacillus sp. (2.74%) that were almost undetected in acacia‐aged beer. Oak barrels also imparted substantial concentrations of eugenol, lactones and vanillin, while acacia‐aged beer contained high concentrations of total polyphenols and β‐glucan, which also translated into different sensory perceptions. Altogether, our results provide novel insights into the barrel‐ageing process of beer, and may pave the way for a new generation of beers with a noteworthy flavour complexity. [ABSTRACT FROM AUTHOR]

Developing knowledge‐transforming skills in writing may help students increase learning by actively building knowledge, regardless of the domain. However, many undergraduate students struggle to transform knowledge when drafting essays based on multiple sources. Writing analytics can be used to scaffold knowledge transforming as writers bring evidence to bear in supporting claims. We investigated how to automatically identify sentences representing knowledge transformation in argumentative essays. A synthesis of cognitive theories of writing and Bloom's typology identified 22 linguistic features to model processes of knowledge transforming in a corpus of 38 undergraduates' essays. Findings indicate undergraduates mostly paraphrase or copy information from multiple sources rather than engage deeply with sources' content. Eight linguistic features were important for discriminating evidential sentences as telling versus transforming source knowledge. We trained a machine learning algorithm that accurately classified nearly three of four evidential sentences as knowledge‐telling or knowledge‐transforming, offering potential for use in future research. Lay Description: What is already known about this topic: Engagement in knowledge transforming in multi‐source writing benefits learning.Post‐secondary writers rarely succeed in knowledge transforming.Computer‐generated formative feedback may promote knowledge‐transforming processes.Computational tools so far developed focused on a composition's rhetorical features only. What this paper adds: We proposed a novel methodology to identify knowledge transforming in argumentative essays.Computational approach involved both rhetorical and content characteristics of evidential sentences.Machine learning algorithm was developed to classify text as knowledge‐transforming versus telling.Eight linguistic features predicted evidential sentences as telling or transforming source knowledge. Implications for practice: There is a clear need to teach post‐secondary students tactics for knowledge transforming.The results can inform the development of writing analytics tool to scaffold knowledge‐transforming revisions. [ABSTRACT FROM AUTHOR]

Stopping land degradation is one of the biggest challenges worldwide and particularly in Burundi, with its unprecedented rates of soil loss and growing food insecurity. This article proposes a different discourse on how to engage people in stopping land degradation, and presents results and lessons learned from a bottom‐up inclusive approach implemented since 2014 in Burundi: the integrated farm planning (PIP) approach. The PIP approach aims to build a solid foundation for sustainable change toward enhanced food production and good land stewardship, based on three foundation principles (motivation, stewardship, and resilience) and three guiding principles (empowerment, integration, and collaboration). This article is based on two studies undertaken in 2018: an impact study among 202 households and a qualitative study using the most significant change methodology with 30 households. Findings from both studies provide initial support that the PIP approach generates considerable changes at household, farm, and village level. Based on a vision and a plan for their farm, motivated PIP households are currently investing in the resilience of their farms and applying a diversity of conservation practices, while in all PIP villages concrete collective action is undertaken for sustainable land stewardship. Given its rapid upscaling in Burundi and the potential of the PIP approach to mobilize farmers for motivated action, the article concludes with a reflection on the core elements of a different discourse to stop land degradation. [ABSTRACT FROM AUTHOR]

Granulomatous skin disease is known to be associated with various primary immunodeficiencies, including ataxia telangiectasia (AT). Recent reports of persistence of live vaccine strain rubella within such cutaneous granulomas have raised concern regarding the safety of vaccination. Here we report a case of cutaneous granuloma in association with AT, demonstrating wild type, rather than vaccine strain rubella. This supports the persistence of rubella as a causative mechanism, but suggests it is not vaccine strain‐specific, and thus may impact the decision of those considering not vaccinating this subset of children. [ABSTRACT FROM AUTHOR]

A stereoselective gold(I)‐catalyzed vinylcyclopropanation of alkenes has been developed. A gold‐coordinated cationic vinyl carbene species, readily generated via a rearrangement of the ethylenedithioacetal of propargyl aldehyde, reacts with a wide range of alkenes to afford thio‐substituted vinylcyclopropanes. The gold‐catalyzed vinyl cyclopropanation proceeds under mild conditions at room temperature and is generally selective for the formation of cis‐substituted cyclopropanes. The reaction allows the formal introduction of a "naked" vinyl carbene, by subsequent chemoselective hydrodesulfurisation of the ethylenedithio‐bridge. The synthetic utility of the new method is demonstrated by a short, racemic formal synthesis of the alkaloid cephalotaxin, hinging on a key vinyl cyclopropane‐cyclopentene rearrangement. [ABSTRACT FROM AUTHOR]

Prolactin is named after its vital role of promoting milk production during lactation, although it has been implicated in multiple functions within the body, including metabolism and energy homeostasis. Prolactin has been hypothesised to play a key role in driving many of the adaptations of the maternal body to allow the mother to meet the physiological demands of both pregnancy and lactation, including the high energetic demands of the growing foetus followed by milk production to support the offspring after birth. Prolactin receptors are found in many tissues involved in metabolism and food intake, such as the pancreas, liver, hypothalamus, small intestine and adipose tissue. We review the literature examining the effects of prolactin in these various tissues and how they relate to changes in function in physiological states of high prolactin, such as pregnancy and lactation, and in pathological states of hyperprolactinaemia in the adult. In many cases, whether prolactin promotes healthy metabolism or leads to dysregulation of metabolic functions is highly dependent on the situation. Overall, although prolactin may not play a major role in regulating metabolism and body weight outside of pregnancy and lactation, it definitely has the ability to contribute to metabolic function. [ABSTRACT FROM AUTHOR]

The design of covalent adaptable networks (CANs) relies on the ability to trigger the rearrangement of bonds within a polymer network. Simple activated alkynes are now used as versatile reversible cross‐linkers for thiols. The click‐like thiol–yne cross‐linking reaction readily enables network synthesis from polythiols through a double Michael addition with a reversible and tunable second addition step. The resulting thioacetal cross‐linking moieties are robust but dynamic linkages. A series of different activated alkynes have been synthesized and systematically probed for their ability to produce dynamic thioacetal linkages, both in kinetic studies of small molecule models, as well as in stress relaxation and creep measurements on thiol–yne‐based CANs. The results are further rationalized by DFT calculations, showing that the bond exchange rates can be significantly influenced by the choice of the activated alkyne cross‐linker. [ABSTRACT FROM AUTHOR]

Prolonged increases in excitation can trigger cell‐wide homeostatic responses in neurons, altering membrane channels, promoting morphological changes, and ultimately reducing synaptic weights. However, how synaptic downscaling interacts with classical forms of Hebbian plasticity is still unclear. In this study, we investigated whether chronic optogenetic stimulation of hippocampus CA1 pyramidal neurons in freely moving mice could (a) cause morphological changes reminiscent of homeostatic scaling, (b) modulate synaptic currents that might compensate for chronic excitation, and (c) lead to alterations in Hebbian plasticity. After 24 hr of stimulation with 15‐ms blue light pulses every 90 s, dendritic spine density and area were reduced in the CA1 region of mice expressing channelrhodopsin‐2 (ChR2) when compared to controls. This protocol also reduced the amplitude of mEPSCs for both the AMPA and NMDA components in ex vivo slices obtained from ChR2‐expressing mice immediately after the end of stimulation. Finally, chronic stimulation impaired the induction of LTP and facilitated that of LTD in these slices. Our results indicate that neuronal responses to prolonged network excitation can modulate subsequent Hebbian plasticity in the hippocampus. [ABSTRACT FROM AUTHOR]

Answering the call for more insights in the relationship between human resource management (HRM), employee well‐being and performance, this study examines the link between developmental human resource (HR) practices and employee task performance, and includes both happiness (i.e., affective organizational commitment) and health related (i.e., exhaustion) well‐being as mediators. Based on social exchange theory and cognitive dissonance theory, we also explore the line manager's developing leadership behaviour as a moderator in the relationship between developmental HRM and well‐being. The multi‐source data from 403 employees and 53 line managers show that distinct developmental HR practices influence well‐being and employee performance differently, and suggest that the developing leadership behaviour of line managers influences the way in which developmental HR practices affect employees. Overall, the results underline the need for a configurational perspective on HRM, well‐being and employee performance, taking line managers' behaviour into account as an essential element of the HRM system, next to formal HR practices. [ABSTRACT FROM AUTHOR]

Salicylate intoxication is a cause of tinnitus in humans and it is often used to produce tinnitus‐like perception in animal models. Here, we assess whether salicylate induces anxiety‐like electrophysiological and behavioral signs. Using microwire electrode arrays, we recorded local field potential in the ventral and, in some experiments dorsal hippocampus, in an open field arena 1 hr after salicylate (300 mg/kg) injection. We found that animals treated with salicylate moved dramatically less than saline treated animals. Salicylate‐treated animals showed a strong 4–6 Hz (type 2) oscillation in the ventral hippocampus (with smaller peaks in dorsal hippocampus electrodes). Coherence in the 4–6 Hz‐theta band was low in the ventral and dorsal hippocampus when compared to movement‐related theta coherence (7–10 Hz). Moreover, movement related theta oscillation frequency decreased and its dependency on running speed was abolished. Our results suggest that salicylate‐induced theta is mostly restricted to the ventral hippocampus. Slow theta has been classically associated to anxiety‐like behaviors. Here, we show that salicylate application can consistently generate low frequency theta in the ventral hippocampus. Tinnitus and anxiety show strong comorbidity and the increase in ventral hippocampus low frequency theta could be part of this association. [ABSTRACT FROM AUTHOR]

Abstract: A stereoselective synthetic method is reported for the molecular framework found in common daucane and isodaucane sesquiterpenoid natural products. The synthetic method constitutes a scalable, modular, and also asymmetric access to a complex natural product scaffold, wherein the substitution pattern and the stereochemistry can be adjusted simply by choosing different starting materials. The method allows the rapid introduction of diverse heterocyclic substructures such as (benzo)furans, (benzo)thiophenes, dithiins, thiazoles, and indoles, which actually also facilitate and direct the key intramolecular annulation step. [ABSTRACT FROM AUTHOR]

Background: Deep versus surface knowledge is widely discussed by educational practitioners. A corresponding construct, levels of processing, has received extensive theoretical and empirical attention in learning science and psychology. In both arenas, lower levels of information and shallower levels of processing are predicted and generally empirically demonstrated to limit knowledge learners gain, curtail what they can do with newly acquired knowledge, and shorten the life span of recently acquired knowledge. Purpose: I recapitulate major accounts of levels or depth of information and information processing to set a stage for conceptualizing, first, self‐regulated learning (SRL) from this perspective and, second, how a “levels‐sensitive” approach might be implemented in research about SRL. Method: I merge the levels construct into a model of SRL (Winne, 2011, Handbook of self‐regulation of learning and performance (pp. 15–32), New York: Routledge; Winne, 2017b, Handbook of self‐regulation of learning and performance (2nd ed.), New York: Routledge; Winne & Hadwin, 1998, Metacognition in educational theory and practice (pp. 277–304). Mahwah, NJ: Lawrence Erlbaum) conceptually and with respect to operationally defining the levels construct in the context of SRL in relation to each of the model's four phases – surveying task conditions, setting goals and planning, engaging the task, and composing major adaptations for future tasks. Select illustrations are provided for each phase of SRL. Regarding phase 3, a software system called nStudy is introduced as state‐of‐the‐art instrumentation for gathering fine‐grained, time‐stamped trace data about information learners select for processing and operations they use to process that information. Conclusions: Self‐regulated learning can be viewed through a lens of the levels construct, and operational definitions can be designed to research SRL with respect to levels. While information can be organized arbitrarily deeply, the levels construct may not be particularly useful for distinguishing among processes except in a sense that, because processes in SRL operate on information with depth, they epiphenomenally acquire characteristics of levels. Thus, SRL per se is not a deeper kind of processing. Instead, it is processing more complex – deeper – information about a different topic, namely processes for learning. [ABSTRACT FROM AUTHOR]

Nonreactive additives are widely applied to enhance polymer properties but can leach out of the material over time. In this work, two essentially different fluorinated additives bearing a triazolinedione moiety are synthesized and grafted on several polydiene backbones (acrylonitrile-butadiene-styrene, styrene-butadiene, and styrene-isoprene-styrene (SIS) copolymers), either by dip-coating or by reaction in solution. The resulting polymers are analyzed by contact angle goniometry, size exclusion chromatography, and NMR, infrared, and X-ray photoelectron spectroscopy. Independent of the modification procedure, the fluorophilic perfluoroalkyl additive is found at the material surface, thereby yielding a more hydrophobic surface. For SIS thermoplastic elastomers, for example, contact angles up to 125° can be obtained. [ABSTRACT FROM AUTHOR]

The title heterocyclic alcohol readily generates a sulfur-substituted allylic cation upon simple treatment with a protic acid, thus facilitating a synthetically useful stepwise (3+2) cycloaddition reaction pathway with a range of conjugated-olefin-type substrates. The introduction of an allyl fragment in this way provided rapid access to a variety of cyclopentanoid scaffolds. The cyclic nature of the cation precursor alcohol was shown to be instrumental for efficient cycloaddition reactions to take place, thus indicating an attractive strategy for controlling the reactivity of heteroatom-substituted allyl cations. The formal cycloaddition reaction is highly regio- and stereoselective and was also used for a short total synthesis of the natural product cuparene in racemic form through a cycloaddition-hydrodesulfurization sequence. [ABSTRACT FROM AUTHOR]

Although the need to prioritize limited conservation resources has prompted increased interest in understanding the functional importance of species within ecosystems, species that are infrequently observed are often written off as being unimportant. In this study, we use aquatic snakes as a case study for examining the importance of secretive predators. Most snakes are extremely cryptic and secretive, traits that not only lead to the perception that they are rare, and of minor importance, but also impede attempts to quantify densities. We used high sampling effort and robust-design capture-recapture analyses to estimate density of aquatic snakes inhabiting an isolated 5.4-ha wetland in South Carolina, USA. We assessed snake diets and coupled field measurements of growth rates with laboratory-derived data on mass conversion efficiency to estimate prey consumption by snakes over a 1-year period. We found a peak density 171 snakes ha-1 of wetland habitat, corresponding to a standing biomass of 7.77 kg ha-1 We calculated that snakes within the wetland consumed a total of over 200 kg (>55 000 individuals) of amphibian prey annually, translating into >150 000 kJ ha-1 of energy flow from secondary to tertiary consumers within the wetland food web. Further, because many amphibians are primarily terrestrial as adults and are consumed by aquatic snakes only when they return to wetlands to breed, snakes can be responsible for substantial transfer of energy and biomass between terrestrial and aquatic habitats. Our study is one of the first comprehensive evaluations of the importance of snakes as predators and underscores the need to consider snakes in initiatives aimed at preserving overall ecosystem integrity. [ABSTRACT FROM AUTHOR]

Exploring a unitarist and pluralist Human Resource Management (HRM) perspective, we propose a more nuanced view on Bowen and Ostroff's (2004) concept of strong HRM processes. More specifically, we investigate whether strong HRM processes contribute positively or negatively to line managers' effective HRM implementation. The results of a multi-level model with data from 125 line managers and 899 employees of five organisations show a complex picture. In line with unitarist thinking, we find a positive indirect effect of strong HRM processes on HRM implementation effectiveness via line managers' ability. In accordance with pluralist thinking, we find a negative direct relationship between strong HRM processes and HRM implementation effectiveness. We discuss the tensions in HRM that might explain these ambiguous findings. [ABSTRACT FROM AUTHOR]

Background The emergence of avian influenza A(H7N9) virus in poultry causing zoonotic human infections was reported on March 31, 2013. Development of A(H7N9) candidate vaccine viruses ( CVV) for pandemic preparedness purposes was initiated without delay. Candidate vaccine viruses were derived by reverse genetics using the internal genes of A/Puerto/Rico/8/34 ( PR8). The resulting A(H7N9) CVVs needed improvement because they had titers and antigen yields that were suboptimal for vaccine manufacturing in eggs, especially in a pandemic situation. Methods Two CVVs derived by reverse genetics were serially passaged in embryonated eggs to improve the hemagglutinin ( HA) antigen yield. The total viral protein and HA antigen yields of six egg-passaged CVVs were determined by the BCA assay and isotope dilution mass spectrometry ( IDMS) analysis, respectively. CVVs were antigenically characterized by hemagglutination inhibition ( HI) assays with ferret antisera. Results Improvement of total viral protein yield was observed for the six egg-passaged CVVs; HA quantification by IDMS indicated approximately a twofold increase in yield of several egg-passaged viruses as compared to that of the parental CVV. Several different amino acid substitutions were identified in the HA of all viruses after serial passage. However, HI tests indicated that the antigenic properties of two CVVs remained unchanged. Conclusions If influenza A(H7N9) viruses were to acquire sustained human-to-human transmissibility, the improved HA yield of the egg-passaged CVVs generated in this study could expedite vaccine manufacturing for pandemic mitigation. [ABSTRACT FROM AUTHOR]

Vitrimers are a new class of polymeric materials with very attractive properties, since they can be reworked to any shape while being at the same time permanently cross-linked. As an alternative to the use of transesterification chemistry, we explore catalyst-free transamination of vinylogous urethanes as an exchange reaction for vitrimers. First, a kinetic study on model compounds reveals the occurrence of transamination of vinylogous urethanes in a good temperature window without side reactions. Next, poly(vinylogous urethane) networks with a storage modulus of ≈2.4 GPa and a glass transition temperature above 80 °C are prepared by bulk polymerization of cyclohexane dimethanol bisacetoacetate, m-xylylene diamine, and tris(2-aminoethyl)amine. The vitrimer nature of these networks is examined by solubility, stress-relaxation, and creep experiments. Relaxation times as short as 85 s at 170 °C are observed without making use of any catalyst. In addition, the networks are recyclable up to four times by consecutive grinding/compression molding cycles without significant mechanical or chemical degradation. [ABSTRACT FROM AUTHOR]

This study evaluated the effectiveness of packaging using a microencapsulated β-cyclodextrin and trans-cinnamaldehyde complex incorporated into a base chitosan matrix on the shelf life of fresh-cut melon ( Cucumis melo L. var. Reticulatus Naud) group Inodorus that were coated with a multilayered coating system using a polypropylene tray ( Ziploc®) with (i) Ziploc® lid, (ii) Saran® wrap and (iii) plain cheesecloth and stored at 4 °C for 15 days. The multilayered antimicrobial coating improved the shelf life of fresh-cut melon (up to 15 days), compared with the controls (7 days). Coated samples were firmer, maintained colour and total carotenoids content and showed less weight loss than the controls ( P < 0.05). Among the packaging treatments, the Ziploc® lid was the most effective in maintaining shelf life. This study demonstrates the application of a new generation of edible coating using natural antimicrobial agents by means of the layer-by-layer assembly. [ABSTRACT FROM AUTHOR]

By using a gallium(III) triflate catalyzed intramolecular (4+3) cycloaddition, a few functionalized furan-derived tricycles that share the common guaianolide sesquiterpene ring system were prepared in a stereoselective manner in only three steps from commercially available starting materials. A discussion of the formation of alternative products is included, with possible substrate requirements to achieve the key cycloaddition step in an efficient way. [ABSTRACT FROM AUTHOR]

A recently developed (4+3) cycloaddition between dienes and furfuryl alcohols, as precursors of oxyallyl-type cations, has been used as a key step in the racemic syntheses of two natural products: frondosin B and liphagal. This work demonstrates the synthetic potential of this cycloaddition reaction, and offers a short synthetic route to an interesting family of natural products. A full account of these synthetic studies is presented, further illustrating the mechanism, scope, and limitations of this straightforward synthetic method for seven-membered rings. [ABSTRACT FROM AUTHOR]

We argue that differentiating HR practices across employees leads employees to compare their situation with colleagues to assess the favourability of HR practice outcomes (e.g. money). These perceptions can be negative (i.e. feeling set back), neutral (i.e. feeling treated the same) or positive (i.e. feeling advantaged). Data from 13,639 Belgian employees showed that perceived favourability of HR practice outcomes is positively associated with affective organisational commitment, but the relationship is attenuated at positive levels. Thus, differentiation may be a double-edged sword as the losses among employees feeling set back may temper, neutralise or even outweigh the benefits among those feeling advantaged. The relationships found were especially salient for work practices (e.g. autonomy) compared with economic practices (e.g. bonuses). Developmental practices were found to be least suited for differentiation across employees. No evidence of a moderating role of employees' preference for equality (vs. differentiation) ivas found. [ABSTRACT FROM AUTHOR]

Competition for prey is thought to be important in structuring snake assemblages. However, due in part to the secretive behavior and low detectability of many snake species, this generalization is based on a limited number of studies, most of which focus on a single study site. We examined differences in diet composition, trophic niche overlap, site occupancy and detectability of five sympatric aquatic snake species between two different habitat types in the Southeastern US, replicated at the landscape scale: permanent wetlands with fishes ( n = 13) and isolated, often ephemeral wetlands without fishes ( n = 10). We collected >3700 prey items from snakes and compared diet composition among snake species to examine niche breadth and overlap, correcting for relative availability of prey captured independently in the same wetlands. We evaluated evidence for competitive exclusion by estimating the probability of co-occupancy for pairs of snake species in each habitat type using occupancy modeling. In wetlands with fishes, niche overlap was low, suggesting resource partitioning. Conversely, in wetlands without fishes, niche overlap was high, with most species feeding on larval or paedomorphic ambystomatid salamanders, but competitive exclusion did not occur. We suggest that high co-occupancy of aquatic snakes in wetlands without fishes despite the apparent lack of resource partitioning is due to a combination of seasonally high abundance of high quality amphibian prey, unique aspects of predator physiology and stochastic abiotic processes that prevent these systems from reaching equilibrium. Our results demonstrate that snake diets can be highly context (e.g. habitat)-specific. Studies should consider other factors in addition to competition for prey when attempting to understand snake population and community dynamics. [ABSTRACT FROM AUTHOR]

Post-transcriptional gene silencing of a primary target gene in plants can coincide with the production of secondary small interfering RNAs (si RNAs) of coding sequences adjacent to the target region and with de novo RNA-directed DNA methylation ( Rd DM) thereof. Here, we analyzed the susceptibility of transgenic and endogenous targets to Rd DM induced by primary and secondary silencing signals. In three different configurations, primary silencing signals were able to direct in trans methylation of chimeric transgenes and the CATALASE2 ( CAT2) endogene; however, extensive spreading of methylation occurred only in the transgene, resulting in the methylation of the flanking CAT2 sequence, whereas methylation of the CAT2 endogene was restricted to the target region and the enclosed introns. The secondary silencing signals arising from this transgenic primary target simultaneously silenced a secondary transgene target and the CAT2 endogene, but were only capable of directing Rd DM to the transgene. Our data indicate that Rd DM is correlated with the in situ generation of secondary si RNAs, occurring in P35S-driven transgenes but not in most endogenes. We conclude that although both endogenes and transgenes are equally sensitive to transitive silencing, differences exist in their susceptibility to undergo secondary Rd DM. [ABSTRACT FROM AUTHOR]

The synthesis of two new A-ring precursors, useful for the convergent assembly of 2α-ethyl and 2β-ethyl derivatives of 19- nor-1α,25-dihydroxyvitamin D3, is described. These building blocks were prepared in 14 steps from quinic acid, which led to a new and practical synthesis of 2α-ethyl-14- epi-19- nor-20- epi-23-yne-1,25(OH)2D3, an analog that shows a remarkably low calcemic effect in mice, while retaining the ability to promote cell differentiation and to inhibit cell proliferation in a number of human cancer cell lines. [ABSTRACT FROM AUTHOR]

Although mark-recapture methods are among the most powerful tools for monitoring wildlife populations, the secretive nature of some species requires a comprehensive understanding of the factors that affect capture probability to maximize accuracy and precision of population parameter estimates (e.g., population size and survivorship). Here, we used aquatic snakes as a case study in applying rigorous markrecapture methods to estimate population parameters for secretive species. Specifically, we used intensive field sampling and robust design markrecapture analyses in Program MARK to test specific hypotheses about ecological and methodological factors influencing detectability of two species of secretive aquatic snakes, the banded watersnake (Nerodia fasciata), and the black swamp snake (Seminatrix pygaea). We constructed a candidate set of a priori mark-recapture models incorporating various combinations of time- and sex-varying capture and recapture probabilities, behavioral responses to traps (i.e., trap-happiness or trap-shyness), and temporary emigration, and we ranked models for each species using Akaike's Information Criterion. For both banded watersnakes and black swamp snakes we found strong support for time-varying capture and recapture probabilities and strong trap-happy responses, factors that can bias population estimation if not accommodated in the models. We also found evidence of sex-dependent temporary emigration in black swamp snakes. Our study is among the first comprehensive assessments of factors affecting detectability in snakes and provides a framework for studies aimed at monitoring populations of other secretive species. [ABSTRACT FROM AUTHOR]

Endogenes rarely support transitive silencing, whereas most transgenes generally allow the spread of silencing to occur along the primary target. To determine whether the presence of introns might explain the difference, we investigated the influence of introns in the primary target on 3′-5′ silencing transitivity. When present in a transgene, an intron-containing endogene fragment does not prohibit the spread of silencing across this fragment, indicating that introns do not preclude silencing transitivity along endogenes. Also, a multiple intron-containing genomic gene fragment that had previously been shown not to support transitivity in an endogenous context could support transitivity when present in a transgene. Nevertheless, genomic intron-containing fragments delayed the onset and diminished the efficiency of transitive silencing of a secondary target compared with the corresponding cDNA fragments. Remarkably, transitivity was impaired proportionally with the length of the pre-mRNA, and not of the mRNA. The latter result suggests that the RNA-dependent RNA polymerase-based spreading of silencing progresses along the non-spliced rather than the fully processed mature mRNA. [ABSTRACT FROM AUTHOR]

Quantifying diet is essential for understanding the functional role of species with regard to energy processing, transfer, and storage within ecosystems. Recently, variance structure in the stable isotope composition of consumer tissues has been touted as a robust tool for quantifying trophic niche width, a task that has previously proven difficult due to bias in direct dietary analyses and difficulties in integrating diet composition over time. We used carbon and nitrogen stable isotope analyses to examine trophic niche width of two sympatric aquatic snakes, banded watersnakes Nerodia fasciata and black swamp snakes Seminatrix pygaea inhabiting an isolated wetland where seasonal migrations of amphibian prey cause dramatic shifts in resource availability. Specifically, we characterized snake and prey isotope compositions through time, space, and ontogeny and examined isotope values in relation to prey availability and snake diets assessed by gut content analysis. We determined that prey cluster into functional groups based on similarity of isotopic composition and seasonal availability. Isotope variance structure indicated that the trophic niche width of the banded watersnake was broader (more generalist) than that of the black swamp snake. Banded watersnakes also exhibited seasonal variation in isotope composition, suggesting seasonal diet shifts that track amphibian prey availability. Conversely, black swamp snakes exhibited little seasonal variation but displayed strong ontogenetic shifts in carbon and nitrogen isotope composition that closely paralleled ontogenetic shifts in their primary prey, paedomorphic mole salamanders Ambystoma talpoideum. Although niche dimensions are often treated as static, our results demonstrate that seasonal shifts in niche dimensions can lead to changes in niche overlap between sympatric species. Such short-term fluctuations in niche overlap can influence competitive interactions and consequently the composition and dynamics of communities and ecosystems. [ABSTRACT FROM AUTHOR]

Background. A program of research is needed that assesses the psychometric properties of instruments designed to quantify students' achievement goal orientations to clarify inconsistencies across previous studies and to provide a stronger basis for future research. Aim. We conducted traditional psychometric and modern Rasch-model analyses of the Achievement Goals Questionnaire (AGQ, Elliot & McGregor, 2001) and the Patterns of Adaptive Learning Scale (PALS, Midgley et al., 2000) to provide an in-depth analysis of the two most popular instruments in educational psychology. Samples and methods. For Study I, 217 undergraduate students enrolled in educational psychology courses participated. Thirty-four were male and 181 were female (two did not respond). Participants completed the AGQ in the context of their educational psychology class. For Study 2, 126 undergraduate students enrolled in educational psychology courses participated. Thirty were male and 95 were female (one did not respond). Participants completed the PALS in the context of their educational psychology class. Results. Traditional psychometric assessments of the AGQ and PALS replicated previous studies. For both, reliability estimates ranged from good to very good for raw subscale scores and fit for the models of goal orientations were good. Based on traditional psychometrics, the AGO and PALS are valid and reliable indicators of achievement goals. Rasch analyses revealed that estimates of reliability for items were very good but respondent ability estimates varied from poor to good for both the AGQ and PALS. These findings indicate that items validly and reliably reflect a group's aggregate goal orientation, but using either instrument to characterize an individual's goal orientation is hazardous. [ABSTRACT FROM AUTHOR]

Although habitat selection has been studied in a variety of snake taxa, little is known about habitat selection in aquatic snake species. Additionally, due to their small size and secretive nature, juvenile snakes are seldom included in habitat selection studies. The Eastern cottonmouth Agkistrodon piscivorus is a semi-aquatic pit viper known to use ambush, sit-and-wait foraging strategies. Ambush hunters are likely to select habitats that increase opportunity for successful prey capture while minimizing predation risk and maintaining appropriate thermal and hydric conditions. We characterized the foraging strategy and microhabitat use of cottonmouths at Ellenton Bay, an isolated Carolina bay freshwater wetland on the Savannah River Site in SC, USA. We measured habitat characteristics of 55 ambush sites used by 51 individual cottonmouths located during nighttime visual surveys, as well as 225 randomly selected sites within our search area. Cottonmouths exhibited an ontogenetic shift in foraging strategy with juveniles using predominately ambush foraging around the edge of the wetland while adults were most often encountered actively moving within the wetland. Principal components analysis revealed that juveniles selected foraging microhabitats that were different from random and consisted of mud substrate with sparse vegetation, whereas adults occupied a greater variety of microhabitats that did not differ from random. Concomitantly, free-ranging cottonmouths exhibited ontogenetic shifts in diet: juveniles consumed mostly salamanders, while adults ate a greater variety of prey including other snakes and birds. Our results highlight the importance of understanding how ontogenetic changes in coloration, diet and predation risk influence foraging strategy and microhabitat selection in snakes. [ABSTRACT FROM AUTHOR]

Background. A programme of construct validity research is necessary to clarify previous research on self-regulation and to provide a stronger basis for future research. Aim. A multitrait-multimethod (MTMM) analysis was conducted to assess convergent and discriminant validity of three self-regulation measures: the Learning and Study Strategies Inventory (LASSI; Weinstein, 1987), the Motivated Strategies for Learning Questionnaire (MSLQ; Pintrich, Smith, Garcia, & McKeachie, 1993) and the Meta-cognitive Awareness Inventory (MAI; Schraw & Dennison, 1994). Method bias across all three inventories was also examined. Sample and method. Three hundred and eighteen undergraduate university students (255 female, 61 male, 2 did not specify) were recruited from various courses to participate in research on perceptions about studying and study methods. Participants spent 30–60 minutes completing all three inventories. Results. Evidence for convergent validity was found at the matrix level, but was attenuated when examined at the individual parameter level. Evidence for discriminant validity among traits was modest, and common method bias was evident across all three measures. Conclusions. Results revealed the three inventories yielded different results, which suggests that researchers should be selective in the inventory they use to assess self-regulated learning (SRL). [ABSTRACT FROM AUTHOR]

1. Most life-history models assume a trade-off between reproductive investment and parental survival. Several studies have documented reproductive costs in terms of reduced locomotor performance in terrestrial habitats. However, few studies have determined the reproductive costs of pregnancy in aquatic environments, or compared pregnancy-induced locomotor costs among habitats. This knowledge gap is important because many organisms rely on multiple habitat types during pregnancy. 2. We compared sexual differences in maximum locomotor velocity and the relative impacts of pregnancy on locomotor performance in aquatic and terrestrial environments for a semi-aquatic snake ( Seminatrix pygaea). In addition, because most life-history models predict a direct trade-off between reproductive investment and reproductive costs, we quantified the relationship between reproductive investment and postpartum increase in velocity for both habitat types. 3. Both males and non-pregnant females always swam faster than they crawled, but males were significantly faster for their size than were non-pregnant females. These results mirror sexual differences known to exist in other snakes, but differ in that the degree of sexual divergence in velocity does not vary with habitat for S. pygaea. 4. Pregnancy significantly reduced both crawling and swimming velocity. Moreover, pregnancy impaired crawling velocity significantly more than swimming velocity. The mean ( ± 1 SE) percentage increases in crawling and swimming velocity after parturition were 72·8 ± 21·6 and 59·4 ± 12·8%, respectively. There was a direct trade-off between reproductive investment and aquatic locomotor impairment: snakes that invested more in offspring experienced larger decreases in swimming velocity. However, evidence for such a trade-off in the terrestrial habitat was weaker. 5. Our results demonstrate that the cost of reproduction for semi-aquatic organisms may differ between aquatic and terrestrial habitats in complex ways. Swimming may be more effective than crawling for escaping predators during pregnancy, because swimming results in faster velocities and is less impaired by pregnancy. However, the assumption of a direct trade-off between reproductive investment and locomotor impairment may be stronger for swimming performance compared with crawling performance. [ABSTRACT FROM AUTHOR]

1. Capital breeding is an ideal reproductive strategy for many ectotherms because it provides a disassociation between feeding and reproduction, a necessary requirement for animals that become anorexic during pregnancy. Among ectotherms, some viviparous snakes (e.g. Viperidae) exemplify the capital breeding strategy because many species (i) do not feed during pregnancy due to behavioural conflicts between reproduction and foraging, and (ii) take more than one season to accumulate sufficient energetic stores for reproduction. 2. Isolated wetlands often exhibit extreme annual fluctuations in environmental conditions with prolonged droughts periodically leaving wetlands completely dry and devoid of prey. Following droughts, however, wetlands can be extremely productive, rendering prey resources virtually unlimited for some species. 3. This study examines drought survival strategy and reproductive ecology of a small aquatic snake Seminatrix pygaea (Cope) in an isolated wetland. Seminatrix pygaea are atypical from most sympatric snake species in that (i) their small body size, reliance on aquatic prey, and high rates of evaporative water loss make them ill-suited to overland movement, and (ii) they may not be subject to costs typically associated with feeding during pregnancy. 4. We hypothesized that S. pygaea would survive periodic multiyear droughts by aestivating within the dried wetland, a survival strategy heretofore undocumented in snakes. Further, we hypothesized that if S. pygaea rely on ‘typical’ snake reproductive strategies of ‘adaptive anorexia’ and capital breeding, reproductive output would be reduced in the first wet year following drought. 5. By encircling a 10-ha wetland with a continuous drift fence before it refilled we were able to demonstrate that S. pygaea were present within the dried wetland prior to the onset of spring rains that refilled the wetland in 2003. Our results suggest that S. pygaea are capable of surviving multiyear droughts by aestivating within the dried wetland. 6. Despite having presumably depleted energy reserves during the drought, S. pygaea reproduced with the same frequency and fecundity during the first season following refilling of the wetland as in pre-drought years. 7. The ability of S. pygaea to rebound rapidly from the stresses of prolonged drought is due in part to their reproductive ecology. Seminatrix pygaea readily feed throughout pregnancy and consequently can rapidly translate high prey abundances into reproductive output through income breeding. [ABSTRACT FROM AUTHOR]

Despite the continuing loss of wetland habitats and associated declines in amphibian populations, attempts to translate wetland losses into measurable losses to ecosystems have been lacking. We estimated the potential productivity from the amphibian community that would be compromised by the loss of a single isolated wetland that has been protected from most industrial, agricultural, and urban impacts for the past 54 years. We used a continuous drift fence at Ellenton Bay, a 10-ha freshwater wetland on the Savannah River Site, near Aiken, South Carolina (U.S.A.), to sample all amphibians for 1 year following a prolonged drought. Despite intensive agricultural use of the land surrounding Ellenton Bay prior to 1951, we documented 24 species and remarkably high numbers and biomass of juvenile amphibians (>360,000 individuals; >1,400 kg) produced during one breeding season. Anurans (17 species) were more abundant than salamanders (7 species), comprising 96.4% of individual captures. Most (95.9%) of the amphibian biomass came from 232095 individuals of a single species of anuran (southern leopard frog[Rana sphenocephala ]). Our results revealed the resilience of an amphibian community to natural stressors and historical habitat alteration and the potential magnitude of biomass and energy transfer from isolated wetlands to surrounding terrestrial habitat. We attributed the postdrought success of amphibians to a combination of adult longevity (often >5 years), a reduction in predator abundance, and an abundance of larval food resources. Likewise, the increase of forest cover around Ellenton Bay from <20% in 1951 to >60% in 2001 probably contributed to the long-term persistence of amphibians at this site. Our findings provide an optimistic counterpoint to the issue of the global decline of biological diversity by demonstrating that conservation efforts can mitigate historical habitat degradation. [ABSTRACT FROM AUTHOR]

Few studies of venomous snakes have addressed how anti-predator behavior may be affected by experience with a potential predator. Because defensive strikes may be costly to snakes, individuals with the ability to learn to discriminate among potentially harmful and non-harmful predatory stimuli should be favored by natural selection. In large venomous snakes, adults are capable of successfully defending themselves against most potential predators, whereas neonates suffer higher predator-induced mortality and are faced with a large diversity of predators. Consequently, we hypothesized that the relative costs of habituation to potential predatory stimuli should vary ontogenetically. This hypothesis predicts that adults should habituate rapidly to non-harmful predatory stimuli, whereas neonates should consistently employ active defensive displays (e.g. striking) because they are at higher risk. To test this prediction, we examined daily changes in the defensive behavior of adult and neonate cottonmouths ( Agkistrodon piscivorus) towards a standardized non-harmful predatory stimulus. As predicted, adults and neonates differed in their tendencies to habituate: adults decreased defensiveness over days while neonates did not. Adults showed habituation of striking components but not of warning displays. Our results support the hypothesis that there may be ontogenetic differences in predator perception. [ABSTRACT FROM AUTHOR]

Locomotor performance is an important fitness-related trait in reptiles because of its potential influence on prey capture and predator avoidance. Because cholinesterase-inhibiting pesticides disrupt neuromuscular signaling, reduction in performance seems to be a logical translation of this biochemical disruption to the organism level. In the present study, we compared the swimming performance of four species of natricine snakes acutely exposed to a formulation of carbaryl to determine whether neonatal body size or skin permeability influences responsiveness. Exposure to high concentrations of carbaryl (2.5-5.0 mg/L) resulted in reduced swimming performance in all four species of snakes, and species responded similarly to the pesticide once body size was accounted for allometrically. Using traditional methods in physiological ecology to estimate skin permeability (a parameter that influences the dose of contaminant absorbed), we found that water flux across the integument also scaled allometrically with body surface area and, therefore, was similar among species after controlling for this relationship. We suggest that future studies examining the effects of repeated low-dose exposure to cholinesterase inhibitors on performance parameters will be useful in assessing the ecological significance of our findings. [ABSTRACT FROM AUTHOR]

The majority of empirical studies on the HRM-performance link report a positive story. The costs associated with the productivity rise due to high performance work practices (HPWP) have been largely neglected. The purpose of this study is to develop a conceptual framework that maps both the value-enhancing and cost-raising impact of HPWP. In addition, we want to pronounce upon their overall effect on financial performance. To test our model, we rely on a sample of small businesses. Understanding both performance and cost-related effects of the implementation of HPWP is particularly valuable for small businesses since they often lack financial resources to implement HPWP and benefit less from economies of scale compared to their larger counterparts. Study results indicate that although greater use of HPWP is associated with increased productivity, this effect is offset by increased labour costs. However, we find an overall positive effect of HPWP on firm profitability. [ABSTRACT FROM AUTHOR]

Theoretical and empirical studies of self-regulation (SR), self-regulated learning (SRL), and closely related constructs such as volition have become lively areas of research in applied psycholgy (e.g. see;).) very thoughtful and representative summary of this work in education packs into their allotted space important contributions to modeling SRL, a discussion of critical methodological matters, a survey of modern empirical research, and manages as well to give useful direction to future research. I, too, have limited space for comment on their article, so I focus on just a few issues that I judge are key. [ABSTRACT FROM AUTHOR]

While reviews abound on theoretical topics in educational psychology, it is rare that we examine our field's instrumentation development, and what effects this has on educational psychology's evolution. To repair this gap, this paper investigates and reveals the implications of software technologies for researching and theorizing about core issues in educational psychology. From a set of approximately 1,500 articles published between 1999 and 2004, we sampled illustrative studies and organized them into four broad themes: (a) innovative ways to operationalize variables, (b) the changing nature of instructional interventions, (c) new fields of research in educational psychology, and (d) new constructs to be examined. In each area, we identify novel uses of these technologies and suggest how they may advance, and, in some instances, reshape theory and methodology. Overall, we demonstrate that software technologies hold significant potential to elaborate research in the field. [ABSTRACT FROM AUTHOR]

1. The hypothesis that high soil temperatures are required to induce both initiation and cessation of daily activity in Whiptail Lizards (Aspidoscelis; formerly Cnemdophorus), as well as the hypotheses that hunger thresholds and high rates of evaporative water loss influence daily activity patterns, were experimentally tested in A. inornata and A. gularis. 2. Although a critical soil temperature was required to elicit the initiation of morning activity, high temperature was not a necessary stimulus for the cessation of activity. 3. Access to prey did not influence the pattern of daily activity; moreover, evaporative water loss did not appear to explain the cessation of afternoon activity. 4. Reversing the photoperiod during our experiments led only to a change in the time of initiation of daily activity (i. e. activity began 12 h later), not a significant change in the duration of daily activity. 5. These results provide strong evidence that circadian cycles can play a critical role in not only the initiation hut also the cessation of activity. 6. While the ultimate cause (i. e. selective advantage, if any) of this unusual circadian rhythm may he related to extreme temperature, limited water supplies or some other exogenous factor, clearly, the rhythm persists in the absence of limiting environmental conditions. [ABSTRACT FROM AUTHOR]