Congruent and Incongruent Corticospinal Activations at the Level of Multiple Effectors

Motor resonance is defined as the subliminal activation of the motor system while observing actions performed by others. However, resonating with another person's actions is not always an appropriate response: In real life, people do not just imitate but rather respond in a suitable fashion. A growing body of neurophysiologic studies has demonstrated that motor resonance can be overridden by complementary motor responses (such as preparing a precision grip on a small object when seeing an open hand in sign of request). In this study, we investigated the relationship between congruent and incongruent corticospinal activations at the level of multiple effectors. The modulation of MEPs evoked by single-pulse TMS over the motor cortex was assessed in upper and lower limb muscles of participants observing a soccer player performing a penalty kick straight in their direction. Study results revealed a double dissociation: Seeing the soccer player kicking the ball triggered a motor resonance in the observer's lower limb, whereas the upper limb response afforded by the object was overridden. On the other hand, seeing the ball approaching the observers elicited a complementary motor activation in upper limbs while motor resonance in lower limbs disappeared. Control conditions showing lateral kicks, mimicked kicks, and a ball in penalty area were also included to test the motor coding of object affordances. Results point to a modulation of motor responses in different limbs over the course of action and in function of their relevance in different contexts. We contend that ecologically valid paradigms are nowadays needed to shed light on the motor system functioning in complex forms of interaction

Development of an improved Pseudoalteromonas haloplanktis TAC125 strain for recombinant protein secretion at low temperature

Background: In a previous paper, we reported the accomplishment of a cold gene-expression system for the recombinant secretion of heterologous proteins in Pseudoalteromonas haloplanktis TAC125. This system makes use of the psychrophilic α-amylase from P. haloplanktis TAB23 as secretion carrier, and allows an effective extra-cellular addressing of recombinant proteins. However, Pseudoalteromonales are reported to secrete a wide range of extra-cellular proteases. This feature works against the efficiency of the cold-adapted secretion system, because of the proteolytic degradation of recombinant products. The aim of this study is the construction of a P. haloplanktis TAC125 mutant strain with reduced extra-cellular proteolytic activity. Results: P. haloplanktis TAC125 culture medium resulted to contain multiple and heterogeneous proteases. Since the annotation of the Antarctic bacterium genome highlighted the presence of only one canonical secretion machinery, namely the Type II secretion pathway (T2SS), we have inactivated this secretion system by a gene insertion strategy. A mutant strain of P. haloplanktis TAC125 in which the gspE gene was knocked-out, actually displayed a remarkable reduction of the extra-cellular protease secretion. Quite interestingly this strain still retained the ability to secrete the psychrophilic amylase as efficiently as the wild type. Moreover, the decrease in extra-cellular proteolytic activity resulted in a substantial improvement in the stability of the secreted amylase-β-lactamase chimera. Conclusion: Here we report a cell engineering approach to the construction of a P. haloplanktis TAC125 strain with reduced extra-cellular protease activity. The improved strain is able to secrete the psychrophilic α-amylase (the carrier of our recombinant secretion system), while it displays a significant reduction of protease content in the culture medium. These features make the gspE mutant an improved host with a remarkable biotechnological potential in recombinant protein secretion at low temperature. Moreover this work demonstrates that P. haloplanktis TAC125 is a versatile psychrophilic host for recombinant protein production since it can be easily improved by a directed engineering approach. To the best of our knowledge, this is the first described example of a strain improvement strategy applied to an Antarctic bacterium

Microsegmentación de la demanda urbana: técnicas innovadoras en la provisión de servicios públicos urbanos

Peer Reviewe

Soil fungi, but not bacteria, track vegetation reassembly across a 30-year restoration chronosequence in the northern jarrah forest, Western Australia

Plant communities have been the primary focus of ecological restoration initiatives; however, the integration of the soil microbiome has become of interest to restoration practice and theory. The inter-dependent nature of the above- and belowground biological environments has led to assumptions that reciprocal shifts in community compositions will occur in response to disturbance and restoration. Ecological restoration of post-mining landscapes within the northern jarrah forest re-instates vegetation communities that are representative of those in adjacent reference forest. The limited studies of soil microbial communities have not addressed whether these communities recover along similar trajectories to plant communities aboveground. Here, a 30-year restoration chronosequence of vegetation development was compared with that of the belowground assemblages of bacteria and fungi, identified using environmental DNA methods. Novel findings of this study highlight similarities between restoration trajectories of fungal and vegetation assemblages, though both remained distinct from reference jarrah forest compositions after 27-years. In contrast, soil bacterial assemblages in restored jarrah forest re-assembled rapidly, with substrate depth being a greater driver of composition than vegetation. Explanatory environmental variables, such as litter cover and initial fertiliser application, were significantly associated with vegetation composition. High covariance among physico-chemical factors made it difficult to establish influences of individual variables on bacterial and fungal communities. Litter depth was significantly associated with fungal composition across the restoration chronosequence, whilst available potassium was associated with both bacterial and fungal community composition. My findings add to a growing body of literature which acknowledges the rich diversity of the belowground microbial community, and the potential for their use as predictors of restoration trajectories. Future research could focus on direct associations between fungi and plant communities, such as potential for fungal inoculation to assist in the rapid reinstatement of missing plants which rely on symbiotic associations with the belowground microbiome

Single prazosin infusion in prelimbic cortex Fosters extinction of amphetamine-induced conditioned place preference

Exposure to drug-associated cues to induce extinction is a useful strategy to contrast cue-induced drug seeking. Norepinephrine (NE) transmission in medial prefrontal cortex has a role in the acquisition and extinction of conditioned place preference induced by amphetamine. We have reported recently that NE in prelimbic cortex delays extinction of amphetamine-induced conditioned place preference (CPP). A potential involvement of α1-adrenergic receptors in the extinction of appetitive conditioned response has been also suggested, although their role in prelimbic cortex has not been yet fully investigated. Here, we investigated the effects of the α1-adrenergic receptor antagonist prazosin infusion in the prelimbic cortex of C57BL/6J mice on expression and extinction of amphetamine-induced CPP. Acute prelimbic prazosin did not affect expression of amphetamine-induced CPP on the day of infusion, while in subsequent days it produced a clear-cut advance of extinction of preference for the compartment previously paired with amphetamine (Conditioned stimulus, CS). Moreover, prazosin-treated mice that had extinguished CS preference showed increased mRNA expression of brain-derived neurotrophic factor (BDNF) and post-synaptic density 95 (PSD-95) in the nucleus accumbens shell or core, respectively, thus suggesting that prelimbic α1-adrenergic receptor blockade triggers neural adaptations in subcortical areas that could contribute to the extinction of cue-induced drug-seeking behavior. These results show that the pharmacological blockade of α1-adrenergic receptors in prelimbic cortex by a single infusion is able to induce extinction of amphetamine-induced CPP long before control (vehicle) animals, an effect depending on contingent exposure to retrieval, since if infused far from or after reactivation it did not affect preference. Moreover, they suggest strongly that the behavioral effects depend on post-treatment neuroplasticity changes in corticolimbic network, triggered by a possible “priming” effect of prazosin, and point to a potential therapeutic power of the antagonist for maladaptive memories

The Perceived Roles of Student Affairs Administrators in Public Higher Education

The field of student affairs administration could benefit from research on how student affairs administrators perceive their duties, responsibilities, and obligations, as well as how such an understanding could contribute to organizational theory, practice, and policy. The purpose of this study was to examine how administrators in student affairs perceive their role in public higher education institutions in the United States. This study examined SAAs’ duties, obligations, and responsibilities (role) using Q methodology. Although there are perception studies using Q methodology in higher education, there are fewer empirical studies on how SAAs’ perceive their roles. Consequently, this study recruited forty professionals in student affairs from 12 public institutions of higher education. On a continuum from “least important” (-4) to “most important” (+4), they sorted 37 statements that represented their views on SAAs’ duties and responsibilities. The 40 sorts were then factor analyzed with PQMethod 2.33 a, freeware program. Four factors emerged that represent distinct viewpoints on the role of student affairs administrators in public tertiary institutions—Connective Leadership, Instructive Leadership, Supportive Leadership, and Constructive Leadership. These four factors—details of which are presented in the study—indicate that student affairs administrators view their roles through four different leadership lenses, but that each lens is modulated or modified by four major theories—self-perception theory, organizational role theory, and, more importantly, student development theory

Existence and multiplicity of heteroclinic solutions for non-autonomous boundary eigenvalue problem

In this paper we investigate the boundary eigenvalue problem x''-b(c,t,x)x'+g(t,x)=0, x(-∞)=0, x(+∞)=1 depending on the real parameter c. We take the function b continuous and positive and assume that g is bounded and becomes active and positive only when it exceeds a threshold value theta in (0,1). At the point theta we allow g to have a jump. Additional monotonicity properties are required, when needed. Our main discussion deals with the non-autonomous case. In this context we prove the existence of a continuum of values for which this problem is solvable and we estimate the interval of such admissible values. In the autonomous case, we show its solvability for at most one c*. In the special case when b=c+h(x) with h continuous, we also give a non-existence result, for any real c. Our methods combine comparison-type arguments, both for first and second order dynamics, with a shooting technique. Some applications of the obtained results are included

Heteroclinic Orbits in Plane Dynamical Systems

We consider general second order boundary value problems on the whole line of the type u''=h(t, u, u'), u(-∞)=0, u(+∞)=1, for which we provide existence, non-existence, multiplicity results. The solutions we find can be reviewed as heteroclinic orbits in the (u, u') plane dynamical system

Early changes in brain structure correlate with language outcomes in children with neonatal encephalopathy.

Global patterns of brain injury correlate with motor, cognitive, and language outcomes in survivors of neonatal encephalopathy (NE). However, it is still unclear whether local changes in brain structure predict specific deficits. We therefore examined whether differences in brain structure at 6 months of age are associated with neurodevelopmental outcomes in this population. We enrolled 32 children with NE, performed structural brain MR imaging at 6 months, and assessed neurodevelopmental outcomes at 30 months. All subjects underwent T1-weighted imaging at 3 T using a 3D IR-SPGR sequence. Images were normalized in intensity and nonlinearly registered to a template constructed specifically for this population, creating a deformation field map. We then used deformation based morphometry (DBM) to correlate variation in the local volume of gray and white matter with composite scores on the Bayley Scales of Infant and Toddler Development (Bayley-III) at 30 months. Our general linear model included gestational age, sex, birth weight, and treatment with hypothermia as covariates. Regional brain volume was significantly associated with language scores, particularly in perisylvian cortical regions including the left supramarginal gyrus, posterior superior and middle temporal gyri, and right insula, as well as inferior frontoparietal subcortical white matter. We did not find significant correlations between regional brain volume and motor or cognitive scale scores. We conclude that, in children with a history of NE, local changes in the volume of perisylvian gray and white matter at 6 months are correlated with language outcome at 30 months. Quantitative measures of brain volume on early MRI may help identify infants at risk for poor language outcomes

Choreographing the Archive: Image Gallery

No abstract available