Domain Specific Lateralization of the Frontal Processes Informing Inhibition: A TMS Study

<p>Response inhibition is the suppression of actions that are inappropriate given some wider context or goal, a capacity that is vital for everyday functioning. In this thesis the theoretical backdrop of executive functioning is discussed, before exploring current research into response inhibition and its neural underpinnings. A theory by Mostofsky and Simmonds (2008) holds that when the decision to inhibit a behavior is a complex one, task dependent parts of an inhibitory network in the prefrontal cortex are utilized. The current thesis argues on the basis of observed biases in the literature, for the possibility that this task dependent engagement features domain specific lateralization. In order to investigate this, a transcranial magnetic stimulation [TMS] experiment is then presented where four go/no-go tasks, spread across language and spatial domains in complex and simple forms, are performed following TMS. Stimulation sites include the right posterior inferior frontal gyrus, the left posterior inferior frontal gyrus, and sham stimulation. Results are then discussed, however implications are limited, likely due to low statistical power.</p>

Domain Specific Lateralization of the Frontal Processes Informing Inhibition: A TMS Study

<p>Response inhibition is the suppression of actions that are inappropriate given some wider context or goal, a capacity that is vital for everyday functioning. In this thesis the theoretical backdrop of executive functioning is discussed, before exploring current research into response inhibition and its neural underpinnings. A theory by Mostofsky and Simmonds (2008) holds that when the decision to inhibit a behavior is a complex one, task dependent parts of an inhibitory network in the prefrontal cortex are utilized. The current thesis argues on the basis of observed biases in the literature, for the possibility that this task dependent engagement features domain specific lateralization. In order to investigate this, a transcranial magnetic stimulation [TMS] experiment is then presented where four go/no-go tasks, spread across language and spatial domains in complex and simple forms, are performed following TMS. Stimulation sites include the right posterior inferior frontal gyrus, the left posterior inferior frontal gyrus, and sham stimulation. Results are then discussed, however implications are limited, likely due to low statistical power.</p>

The obedient mind and the volitional brain: A neural basis for preserved sense of agency and sense of responsibility under coercion

Milgram’s classical studies famously suggested a widespread willingness to obey authority, even to the point of inflicting harm. Important situational factors supporting obedience, such as proximity with the victim, have been established. Relatively little work has focused on how coercion affects individual cognition, or on identifying the cognitive factors that underlie inter-individual differences in the tendency to yield to coercion. Here, we used fMRI to investigate the neural systems associated with changes in volitional processes associated with sense of agency and sense of responsibility under coercion. Participants either freely chose, or were instructed by the experimenter, to give mildly painful electric shocks to another participant, or to refrain from doing so. We have previously shown that coercion reduces temporal binding, which has been proposed as an implicit proxy measure of sense of agency. We tested how reduced agency under coercion related to differences in neural activity between free choice and coercion. In contrast to previous studies and to participants performing the task outside the MRI scanner, on average there was no effect of coercion on agency for participants in the scanner. However, greater activity in the medial frontal gyrus was reliably associated with greater agency under coercion. A similar association was found using explicit responsibility ratings. Our findings suggest that medial frontal processes, perhaps related to volition during action planning and execution, may help to preserve a sense of accountability under coercion. Further, participants who administered more shocks under free choice showed reduced activity during free choice trials in brain areas associated with social cognition. Possibly, this might reflect participants cognitively distancing themselves from the recipient of the shocks under free choice, whereas this was not observed under coercion.

Instrumented Wave Gliders for Air-Sea Interaction and Upper Ocean Research

Over the last several years, the Air-Sea Interaction Laboratory at Scripps Institution of Oceanography has developed a fleet of wave-powered, uncrewed Wave Gliders (Liquid Robotics) specifically designed and instrumented for state-of-the-art air-sea interaction and upper ocean observations. In this study, measurement capabilities from these platforms are carefully described, compared, and validated against coincident measurements from well-established, independent data sources. Data collected from four major field programs from 2013 to 2020 are considered in the analysis. Case studies focusing on air-sea interaction, Langmuir circulations, and frontal processes are presented. We demonstrate here that these novel, instrumented platforms are capable of collecting observations with minimal flow-structure interaction in the air-sea boundary layer, a region of crucial current and future importance for models of weather and climate.

Skills and limitations of the adiabatic omega equation: how effective is it to retrieve oceanic vertical circulation at meso and submesoscale ?

The quasi-geostrophic and the generalized omega equations are the most widely used methods to reconstruct vertical velocity (w) from in-situ data. As observational networks with much higher spatial and temporal resolutions are being designed, the question rises of identifying the approximations and scales at which an accurate estimation of w through the omega equation can be achieved and what are the critical scales and observables needed. In this paper we test different adiabatic omega reconstructions of w over several regions representative of main oceanic regimes of the global ocean in a fully eddy-resolving numerical simulation with a 1=60o horizontal resolution. We find that the best reconstructions are observed in conditions characterized by energetic turbulence and/or weak stratification where near-surface frontal processes are felt deep into the ocean interior. The quasi-geostrophic omega equation gives satisfactory results for scales larger than ~ 10 km horizontally while the improvements using a generalized formulation are substantial only in conditions where frontal turbulent processes are important (providing improvements with satisfactory reconstruction skill down to ~ 5 km in scale). The main sources of uncertainties that could be identified are related to processes responsible for ocean thermal wind imbalance (TWI), which is particularly difficult to account for (especially in observation-based studies) and to the deep flow which is generally improperly accounted for in omega reconstructions through the bottom boundary condition. Nevertheless, the reconstruction of mesoscale vertical velocities may be sufficient to estimate vertical fluxes of oceanic properties in many cases of practical interest.

Analysis and Optimal Design of Batch and Two-Column Continuous Chromatographic Frontal Processes for Monoclonal Antibody Purification

Frontal chromatography has seen increased interest for protein purification, in particular as a polishing step in downstream processes for therapeutic proteins production, as for example the purification of monoclonal antibodies (mAbs) from high molecular weight impurities, e.g., aggregates, using cation exchange resins. In this work we introduce a new two-column continuous process implementing frontal chromatography. The design procedure and its performance, compared to classical batch technology, are discussed. This represents an additional option in the realisation of optimised continuous downstream processing of therapeutic proteins.

Symmetric Instability and Ageostrophic Secondary Circulation in the East Korea Warm Current

&lt;p&gt;Submesoscale dynamics and ocean-atmosphere exchange process in frontal regions play an important role in regulating ocean overturning circulation and cycles of materials (including carbon) and energy, yet our understanding on the dynamics is limited primarily due to lack of relevant observation. To investigate frontal processes such as symmetric instability (SI) and ageostrophic secondary circulation (ASC), multiple comprehensive hydrographic and current observations were made with marine meteorological measurements across a sharp front of the East Korea Warm Current (EKWC) over spring 2017, summer 2017 and fall 2018. Submesoscale features were identified from the observations, estimating diagnostic variables that are the Ertel&amp;#8217;s potential vorticity (f&lt;sub&gt;q&lt;/sub&gt;), balanced Richardson number angle ( ), and Ekman buoyancy flux (EBF). The results with f&lt;sub&gt;q&lt;/sub&gt; &lt; 0 along the front, &amp;#160;corresponding to SI regime, and enhanced EBF along the surface of front support that submesoscale overturning circulation induced by down-front wind is due to the SI and ASC. The ASCs with ageostrophic current estimated using the Omega equations further provide vertical motions in the vicinity of the front. Our results suggest that the western boundary currents like EKWC within the North Pacific marginal sea strongly interact with local wind to impact submesoscale overturning circulation and (re-)distribution of materials via SI and ASC.&lt;/p&gt;

Orbital reconstruction for tumor-associated proptosis: quantitative analysis of postoperative orbital volume and final eye position

OBJECTIVESurgical resection of sphenoid wing tumors and intraorbital pathology carries the dual goal of appropriately treating the target pathology as well as correcting proptosis. Residual proptosis following surgery can lead to cosmetic and functional disability. The authors sought to quantitatively assess the effect of orbital volume before and after reconstruction to determine the optimal strategy to achieve proptosis correction.METHODSAll surgeries involving orbital wall reconstruction for orbital or intracranial pathology that preoperatively resulted in proptosis between 2007 and 2017 were reviewed. Proptosis was measured by the exophthalmos index (EI): the ratio of the distance of the anterior limit of each globe to a line drawn between the anterior limit of the frontal processes of the zygomas, comparing the pathological eye to the normal eye. Postoperative radiographic measurements were taken at least 60 days after surgery to allow surgical swelling to abate. The orbit contralateral to the pathology was used as an internal control for normal anatomical orbital volume. Cases with preoperative EI < 1.10, orbital exenteration, or enucleation were excluded.RESULTSTwenty-three patients (16 females and 7 males, with a mean age of 43.6 ± 22.8 years) were treated surgically for tumor-associated proptosis. Nineteen patients harbored meningiomas (11 en-plaque; 8 sphenoid wing), and one patient each harbored an orbital schwannoma, glomangioma, arteriovenous malformation, or cavernous hemangioma. Preoperative EI averaged 1.28 ± 0.10 (range 1.12–1.53). Median time to postoperative imaging was 19 months. Postoperatively, the EI decreased to a mean of 1.07 ± 0.09. Greater increases in size of the reconstructed orbit were positively correlated with greater quantitative reductions in proptosis (p < 0.01). Larger volume of soft tissue pathology was also associated with achieving greater proptosis correction (p < 0.01). Residual exophthalmos (defined as EI > 1.10) was present in 8 patients, while reconstruction in 2 patients resulted in clinically asymptomatic enophthalmos (defined as EI < 0.95). Tumor invasion into the superior orbital fissure sinus was associated with residual proptosis (p = 0.04).CONCLUSIONSProptosis associated with intracranial and orbital pathology represents a surgical challenge. The EI is a reliable and quantitative assessment of proptosis. For orbital reconstruction in cases of superior orbital fissure involvement, surgeons should consider rebuilding the orbit at slightly larger than anatomical volume.