509 research outputs found
Adolescent methylphenidate treatment differentially alters adult impulsivity and hyperactivity in the Spontaneously Hypertensive Rat model of ADHD
Impulsivity and hyperactivity are two facets of attention deficit/hyperactivity disorder (ADHD). Impulsivity is expressed as reduced response inhibition capacity, an executive control mechanism that prevents premature execution of an intermittently reinforced behavior. During methylphenidate treatment, impulsivity and hyperactivity are decreased in adolescents with ADHD, but there is little information concerning levels of impulsivity and hyperactivity in adulthood after adolescent methylphenidate treatment is discontinued. The current study evaluated impulsivity, hyperactivity as well as cocaine sensitization during adulthood after adolescent methylphenidate treatment was discontinued in the Spontaneously Hypertensive Rat (SHR) model of ADHD. Treatments consisted of oral methylphenidate (1.5mg/kg) or water vehicle provided Monday-Friday from postnatal days 28-55. During adulthood, impulsivity was measured in SHR and control strains (Wistar Kyoto and Wistar rats) using differential reinforcement of low rate (DRL) schedules. Locomotor activity and cocaine sensitization were measured using the open-field assay. Adult SHR exhibited decreased efficiency of reinforcement under the DRL30 schedule and greater levels of locomotor activity and cocaine sensitization compared to control strains. Compared to vehicle, methylphenidate treatment during adolescence reduced hyperactivity in adult SHR, maintained the lower efficiency of reinforcement, and increased burst responding under DRL30. Cocaine sensitization was not altered following adolescent methylphenidate in adult SHR. In conclusion, adolescent treatment with methylphenidate followed by discontinuation in adulthood had a positive benefit by reducing hyperactivity in adult SHR rats; however, increased burst responding under DRL compared to SHR given vehicle, i.e., elevated impulsivity, constituted an adverse consequence associated with increased risk for cocaine abuse liability.P50 DA005312 - NIDA NIH HHS; R01 DA011716 - NIDA NIH HHS; P50 DA05312 - NIDA NIH HH
Online corporate social responsibility communication by Australian SMEs : a framework for website analysis
There has been almost no IS related corporate social responsibility (CSR) research on small and medium enterprises (SMEs), and most non-IS research does not examine how SMEs use websites to communicate their CSR initiatives. This paper develops and applies a framework to report on the results of an exploratory content analysis of 33 Australian SME websites in the Information Media/Telecommunications and Accommodation/ Food Services sectors which communicate CSR initiatives online.<br /
How do Australian small and medium enterprises communicate their environmental improvement activities online?
There have been calls in the IS/eBusiness literature for research on "green" IS/IT in a Small and Medium Enterprises (SMEs) context. The Corporate Social Responsibility (CSR) literature has neglected the issue of how SMEs can use websites to communicate their environmental improvement activities. This paper links these two previously separate disciplines by reporting on a content analysis of 443 Australian SME websites from four industry sectors to identify if and how they use websites to communicate their environmental improvement activities. The study found that 47 websites were communicating such activities in some form. A detailed analysis was undertaken of these 47 websites to identify emergent themes relating to how these SMEs were communicating their environmental improvement activities. These themes resulted in a reconceptualisation of the traditional "4 Ps" of marketing for online communication of environmental improvement activities by SMEs: profile; product; process; and prominence.<br /
Australian public sector adoption of EDRMS : a preliminary survey
Governments around the world are placing increasing emphasis on effective corporate recordkeeping within both private and public sector organisations, with some governments mandating such approaches: for example, The State Government of South Australia has required all its agencies to have \u27an adequate records management program\u27 in place by the end of 2009 (State Records of South Australia 2007). These demands are often met through the implementation of centralised electronic records management solutions – frequently, Electronic Document and Records Management Systems (EDRMS) – but not all implementing organisations adopt an EDRMS solution in the most optimal way; and many such systems fail to meet organisational needs, or gain acceptance form all (or even most) users. This paper reports on a Web-based survey of Australian public sector EDRMS implementation at three levels (federal, state and local government) and forms the first component of a multi-part investigation of Australian public sector records management. This preliminary survey was designed to identify the EDRMS solutions adopted by government agencies, as well as any guidelines or frameworks used in designing and implementing those solutions.<br /
A method for examining corporate social responsibility descriptions on SME websites
There is growing IS research concerning SME use of websites and limited but growing research on corporate social responsibility (CSR) by SMEs. However, to-date these two bodies of literature have remained largely separate. This paper links these fields by presenting an SME website content analysis method. Melville in his seminal MIS Quarterly article called for such methods which provide a nexus of IS, organisations and environment (which we extend to CSR). The method involves four steps: 1) identifying sources of SME websites; 2) determining if websites are describing CSR (based on the literature CSR by SMEs); 3) archiving website content for analysis; and 4) coding the website content using a structured framework (combining the literature on IS and CSR in an SME context). The paper also provides suggestions on how IS researchers can apply the method for quantitative and qualitative/exploratory objectives for future research.<br /
Individual differences in behavioral responses to novelty and amphetamine self-administration in male and female rats
Previous work has shown that individual differences in locomotor activity in an inescapable novel environment can predict acquisition of amphetamine self-administration. The current study examined whether individual differences in approach to novelty in a free choice test could also predict amphetamine self-administration. Further, the current study examined whether individual differences in either free choice or inescapable novelty tests could predict responding for a nondrug reinforcer (sucrose) in the presence and absence of amphetamine. Male and female rats were first tested for their response to free choice novelty (playground maze and novelty-induced place preference tests) and inescapable novelty. They were then tested for acquisition of sucrose-reinforced responding, amphetamine-induced changes in maintenance of sucrose-reinforced responding, and amphetamine self-administration. Based on the inescapable novelty test, acquisition of sucrose-reinforced responding was more rapid in male high responders (HR) compared to low responders (LR). This effect in males did not generalize to females. None of the novelty tests predicted the ability of amphetamine to decrease sucrose-maintained responding. However, using the inescapable novelty test, both male and female HRs self-administered more amphetamine than LRs within the dose range tested (0.03-0.16mg/ kg/infusion). Neither the playground maze nor the novelty-induced place preference test predicted amphetamine self-administration. These results indicate that responses to free choice novelty and inescapable novelty predict different components of amphetamine-induced behavior
Conceptualising how SMEs incorporate green content in their websites
This paper presents a framework on how Small and Medium Enterprises (SMEs) can proactively incorporate content relating to their ecological responsibility (or green) activities in their websites. SME studies offer limited guidance on, and conceptualisation of, how organisations can incorporate different types of content into their website designs. This paper addresses this problem by presenting the results of an exploratory, qualitative content analysis of Australian SME websites where emergent themes are interpreted using framing and legitimacy theories. It describes three dimensions (location, presentation, and specificity) which comprise the framework, under which the themes are grouped. The paper outlines how scholars can use the framework to develop models and carry out evaluations regarding how SMEs embed green content, and potentially other specific content types, in their websites. It also summarises how the framework can assist SMEs (or website developers serving them) make informed decisions regarding framing their websites as green, or de-emphasising this content, by paying attention to its location (e.g. homepage, navigation bars) and presentation (e.g. how paragraphs, images, etc are used) within webpages. The legitimacy or credibility of the green content can be enhanced using different types of specificity (e.g. statistics, detail of processes and actions, and third-party substantiation)
Morphine taste conditioning and analgesia: Assessing conditioned and novelty-induced analgesia.
Evidence for habitual climbing in a Pleistocene hominin in South Africa
Bipedalism is a defining trait of the hominin lineage, associated with a transition from a more arboreal to a more terrestrial environment. While there is debate about when modern human-like bipedalism first appeared in hominins, all known South African hominins show morphological adaptations to bipedalism, suggesting that this was their predominant mode of locomotion. Here we present evidence that hominins preserved in the Sterkfontein Caves practiced two different locomotor repertoires. The trabecular structure of a proximal femur (StW 522) attributed to Australopithecus africanus exhibits a modern human-like bipedal locomotor pattern, while that of a geologically younger specimen (StW 311) attributed to either Homo sp. or Paranthropus robustus exhibits a pattern more similar to nonhuman apes, potentially suggesting regular bouts of both climbing and terrestrial bipedalism. Our results demonstrate distinct morphological differences, linked to behavioral differences between Australopithecus and later hominins in South Africa and contribute to the increasing evidence of locomotor diversity within the hominin clade
Optimization of the Kinematic Chain of the Thumb for a Hand Prosthesis Based on the Kapandji Opposition Test
Ponènica presentada a International Symposium on Computer Methods in Biomechanics and Biomedical Engineering - CMBBE 2019The thumb plays a key role in the performance of the hand for grasp-ing and manipulating objects. In artificial hands the complex thumb’s kinematic chain (TKC) is simplified and its five degrees of freedom are reduced to only one or two with the consequent loss of dexterity of the hand. The Kapandji op-position test (KOT) has been clinically used in pathological human hands for evaluating the thumb opposition and it has also been employed in some previ-ous studies as reference for the design of the TKC in artificial hands, but with-out a clearly stated methodology. Based on this approaches, in this study we present a computational method to optimize the whole TKC (base placement, link lengths and joint orientation angles) of an artificial hand based on its per-formance in the KOT. The cost function defined for the optimization (MPE) is a weighted mean position error when trying to reproduce the KOT postures and can be used also as a metric to quantify thumb opposition in the hand. As a case study, the method was applied to the improvement of the TKC of an artificial hand developed by the authors and the MPE was reduced to near one third of that of the original design, increasing significantly the number of reachable po-sitions in the KOT. The metric proposed based on the KOT can be used directly or in combination with other to improve the kinematic chain of artificial hands
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