Disentangling causal webs in the brain using functional Magnetic Resonance Imaging: A review of current approaches

In the past two decades, functional Magnetic Resonance Imaging has been used to relate neuronal network activity to cognitive processing and behaviour. Recently this approach has been augmented by algorithms that allow us to infer causal links between component populations of neuronal networks. Multiple inference procedures have been proposed to approach this research question but so far, each method has limitations when it comes to establishing whole-brain connectivity patterns. In this work, we discuss eight ways to infer causality in fMRI research: Bayesian Nets, Dynamical Causal Modelling, Granger Causality, Likelihood Ratios, LiNGAM, Patel's Tau, Structural Equation Modelling, and Transfer Entropy. We finish with formulating some recommendations for the future directions in this area

Turn-Taking and the Local Management of Conversation in a Highly Simultaneous Computer-Mediated Communication System

Ongoing inquiry in communication technology research includes the questions of whether and how users adapt communication to the relatively restricted codes provided by text-based computer-mediated communication (CMC). This study proposes that adaptations may be affected by the level of simultaneity in messaging that CMC systems afford users. This suggestion is examined through an analysis of the particular conversational management strategies afforded by a fully synchronous computer-mediated communication system in which message transmission is keystroke-by-keystroke. Conversation analyses performed on the transcript of a three-person online conversation suggest several conclusions: Despite the novelty of the system, the CMC users appropriated and adapted many techniques from face-to-face conversations for the local management of conversations, including turn taking, turn allocation, and explicit interruption management. At the time, turn exchange was accomplished by the use of overlapping intermittent talk followed by lengthy strategic pauses, rather than according to the “no gap, no overlap” ideal of spoken conversation. Overall, the computer-mediated exchanges appeared resilient to modality change, and users spontaneously and creatively employed both traditional and technical features of conversation management

Sea level rise vulnerability assessment for State wildlife areas surrounding Humboldt Bay, northern California

Humboldt Bay has the highest rate of sea level rise (SLR) in California (47.2 cm/century). Due to compaction and tectonic subsidence, former tidelands and pastures behind dikes surrounding Humboldt Bay are lower in elevation than bay waters at high tide. Adaptation to future climate change and SLR requires that resource managers understand vulnerability and risk to each wildlife area at a local level, because adaptation to SLR is a risk-based management strategy against an uncertain future requiring site-specific solutions. We conducted a vulnerability assessment of the shoreline of three State wildlife areas surrounding Humboldt Bay: Elk River (ERWA), Fay Slough (FSWA), and Mad River Slough (MRSWA). Breaching of shorelines that border each refuge has the potential to flood a diversity of wetland communities, wildlife habitats, and critical infrastructure within the historic tidal inundation footprint. The total length of diked 1-m shoreline segments potentially impacted by SLR was 6.2 km. The relationship between vulnerability and elevation of diked shoreline segments was significantly correlated for all wildlife areas. Vulnerability of diked shoreline was significantly affected by the type of surface covering. MRSWA had the highest percentage of shoreline fortified with concrete and rock (62.2% [2,876 m]), followed by ERWA (0.3% [2,815 m]). ERWA and FSWA had the greatest percentage of shoreline anchored by vegetation (99.3% [2,834 m] and 91.5% [3,385 m], respectively); FSWA had the highest percentage of unvegetated (i.e., exposed) shoreline (7.4% [252 m]); and ERWA had the highest percentage (86.6% [436 m]) of diked shoreline followed by FSWA (69.2% [633 m]) and MRSWA (33.0% [276 m]). The highest overall ratings of shoreline vulnerability were at ERWA (91.7%), followed by FSSWA (72,4%), and MRSWA (34.4%). Issues related to retention of unique characteristics of each wildlife area, natural resources and species at risk, and adaptive planning for future SLR are discussed

Mrgprd Enhances Excitability in Specific Populations of Cutaneous Murine Polymodal Nociceptors

The Mas-related G protein-coupled receptor D (Mrgprd) is selectively expressed in nonpeptidergic nociceptors that innervate the outer layers of mammalian skin. The function of Mrgprd in nociceptive neurons and the physiologically relevant somatosensory stimuli that activate Mrgprd^-expressing (Mrgprd^+) neurons are currently unknown. To address these issues, we studied three Mrgprd knock-in mouse lines using an ex vivo somatosensory preparation to examine the role of the Mrgprd receptor and Mrgprd+ afferents in cutaneous somatosensation. In mouse hairy skin, Mrgprd, as marked by expression of green fluorescent protein reporters, was expressed predominantly in the population of nonpeptidergic, TRPV1-negative, C-polymodal nociceptors. In mice lacking Mrgprd, this population of nociceptors exhibited decreased sensitivity to cold, heat, and mechanical stimuli. Additionally, in vitro patch-clamp studies were performed on cultured dorsal root ganglion neurons from Mrgprd^(–/–) and Mrgprd^(+/–) mice. These studies revealed a higher rheobase in neurons from Mrgprd^(–/–) mice than from Mrgprd^(+/–) mice. Furthermore, the application of the Mrgprd ligand β-alanine significantly reduced the rheobase and increased the firing rate in neurons from Mrgprd^(+/–) mice but was without effect in neurons from Mrgprd^(–/–) mice. Our results demonstrate that Mrgprd influences the excitability of polymodal nonpeptidergic nociceptors to mechanical and thermal stimuli

Outcomes in patients sustaining complex periarticular fracture-dislocations of the elbow [abstract]

Periarticular fracture-dislocations (dislocations associated with one or more fractures) of the elbow are difficult injuries to treat. They have historically been associated with poor treatment strategies which resulted in abysmal outcomes for patients. We aimed to review our management strategies for these complex injuries and patient outcomes

Neuropsychiatric Profiles in Dementia

This is the author's accepted manuscript. The original is available at http://pt.wkhealth.com/pt/re/lwwgateway/landingpage.htm;jsessionid=Wy1M9PqrBY1LGf0bN3QqF0h42YJqr4mTnW1ZdGT87Wllb4qvTbQb!-396536289!181195628!8091!-1?sid=WKPTLP:landingpage&an=00002093-201110000-00006We compared patterns of neuropsychiatric symptom across four dementia types (AD, VAD, DLB, PDD), and two mixed groups (AD/VAD, AD/DLB) in sample of 2,963 individuals from the National Alzheimer’s Coordinating Center Uniform Data Set between September 2005 and June 2008. We used confirmatory factor analysis to compare neuropsychiatric symptom severity ratings made by collateral sources on the Neuropsychiatric Inventory (NPI-Q) for people with Clinical Dementia Rating scores of 1 or higher. A three factor model of psychiatric symptoms (mood, psychotic, and frontal) was shared across all dementia types. Between-group comparisons revealed unique neuropsychiatric profiles by dementia type. The AD group had moderate levels of mood, psychotic, and frontal symptoms while VAD exhibited the highest levels and PDD had the lowest levels. DLB and the mixed dementias had more complex symptom profiles. Depressed mood was the dominant symptom in people with mild diagnoses. Differing psychiatric symptom profiles provide useful information regarding the non-cognitive symptoms of dementia