Mineralogy and Geochemistry of Pleistocene Volcanics at Embagai Caldera and Natron Basin, Tanzania: Potential Constraints on the Stratigraphy of Olduvai Gorge

Olduvai Gorge is a paleoanthropologically significant site on the shoulder of the East African Rift Valley of north-central Tanzania, hosting Pleistocene-aged hominid fossils and stone tools. Several volcanoes in the adjacent Ngorongoro Volcanic Highlands (NVH) have erupted volcanic material into Olduvai and other nearby sedimentary basins. Embagai (Elanairobi) is a Pleistocene caldera within the NVH. It is a potential source volcano for Olduvai tuffs, particularly for Bed II and younger deposits, as it is consistent in overall composition (nephelinite and trachybasalt) and general age. Nephelinitic and phonolitic lava and tuff samples were collected from the caldera floor and the western, eastern, and northeastern sides of the caldera. Common primary minerals included nepheline, clinopyroxenes, titanomagnetite, and andradite garnets exclusive to alkaline volcanic settings. Secondary alteration significantly affected the quality of the geochemical and mineralogical results, with analcime, phillipsite, and calcite as the dominant secondary minerals. Unaffected samples plot as nephelinites. The compositions of phenocrysts of augite, feldspar, and titanomagnetite sampled from both Embagai and the Olduvai beds were compared. High-Mg augite compositions from the northern rim and western flank of Embagai are most similar to those of Olduvai Bed II. Feldspars are rare and distinctively K-rich in Embagai samples, which are dominated by nepheline compared to Olduvai tuffs. Overall, the mineral compositions and assemblage of Embagai appear to be a better match for a younger Olduvai Bed III tuff. The Pleistocene Peninj Group, exposed to the north of the NVH along the western margin of Lake Natron, is also paleoanthropologically important. It is comprised of the Humbu and Moinik Formations, which contain clastic sediments along with tephras and lavas likely associated with local eruptions from nearby volcanoes. The Main Tuff within the Humbu Formation is interlaid with the Wa Mbugu Basalt to the south of Peninj. This study compares the geochemistry and paleomagnetism of both well-constrained and unknown samples of the Wa Mbugu and other basaltic lavas in the vicinity to constrain the various units in this highly faulted and fragmented region. Samples were variably altered, with zeolites dominating the alteration assemblage. Geochemical results indicate that bulk major and minor elements alone are not enough to distinguish between some lavas of different stratigraphic positions but similar compositions, and would require further study using trace elements, phenocryst compositions, or other means. An oriented sample of the Wa Mbugu appears to indicate transitional polarity as opposed to the normal polarity commonly found with this unit. A second oriented lava sample had reversed polarity, however is not compositionally similar to the nearby Hajaro lava (reversed). This second lava may represent a previously undocumented flow. With further study of both Embagai and the Natron basin lavas focusing on phenocryst mineralogy in unaltered samples, additional correlations could lead to a higher resolution inter-basin stratigraphic framework for the NVH and for the surrounding paleontologically and archaeologically important sedimentary basins

Wireless Sensing of Lower Lip and Thumb-Index Finger ‘Ramp-and-Hold’ Isometric Force Dynamics in a Small Cohort of Unilateral MCA Stroke: Discussion of Preliminary Findings

Automated wireless sensing of force dynamics during a visuomotor control task was used to rapidly assess residual motor function during finger pinch (right and left hand) and lower lip compression in a cohort of seven adult males with chronic, unilateral middle cerebral artery (MCA) stroke with infarct confirmed by anatomic magnetic resonance imaging (MRI). A matched cohort of 25 neurotypical adult males served as controls. Dependent variables were extracted from digitized records of ‘ramp-and-hold’ isometric contractions to target levels (0.25, 0.5, 1, and 2 Newtons) presented in a randomized block design; and included force reaction time, peak force, and dF/dtmax associated with force recruitment, and end-point accuracy and variability metrics during the contraction hold-phase (mean, SD, criterion percentage ‘on-target’). Maximum voluntary contraction force (MVCF) was also assessed to establish the force operating range. Results based on linear mixed modeling (LMM, adjusted for age and handedness) revealed significant patterns of dissolution in fine force regulation among MCA stroke participants, especially for the contralesional thumb-index finger followed by the ipsilesional digits, and the lower lip. For example, the contralesional thumb-index finger manifest increased reaction time, and greater overshoot in peak force during recruitment compared to controls. Impaired force regulation among MCA stroke participants during the contraction hold-phase was associated with significant increases in force SD, and dramatic reduction in the ability to regulate force output within prescribed target force window (±5% of target). Impaired force regulation during contraction hold-phase was greatest in the contralesional hand muscle group, followed by significant dissolution in ipsilateral digits, with smaller effects found for lower lip. These changes in fine force dynamics were accompanied by large reductions in the MVCF with the LMM marginal means for contralesional and ipsilesional pinch forces at just 34.77% (15.93 N vs. 45.82 N) and 66.45% (27.23 N vs. 40.98 N) of control performance, respectively. Biomechanical measures of fine force and MVCF performance in adult stroke survivors provide valuable information on the profile of residual motor function which can help inform clinical treatment strategies and quantitatively monitor the efficacy of rehabilitation or neuroprotection strategies

Classification of Tactile and Motor Velocity-Evoked Hemodynamic Response in Primary Somatosensory and Motor Cortices as Measured by Functional Near-Infrared Spectroscopy

Functional near-infrared spectroscopy (fNIRS) is an emerging technique in studying cerebral hemodynamics; however, consensus on the analysis methods and the clinical applications has yet to be established. In this study, we demonstrate the results of a pilot fNIRS study of cerebral hemodynamic response (HR) evoked by pneumotactile and sensorimotor stimuli on the dominant hand. Our goal is to find the optimal stimulus parameters to maximally evoke HR in the primary somatosensory and motor cortices. We use a pulsatile pneumatic array of 14 tactile cells that were attached to the glabrous surface of the dominant hand, with a patterned stimulus that resembles saltation at three distinct traverse velocities [10, 25, and 45 cm/s]. NIRS optodes (16 sources; 20 detectors) are bilaterally and symmetrically placed over the pre-and post-central gyri (M1 and S1). Our objective is to identify the extent to which cerebral HR can encode the velocity of the somatosensory and/or motor stimuli. We use common spatial pattern for feature extraction and regularized-discriminant analysis for classifying the fNIRS time series into velocity classes. The classification results demonstrate discriminatory features of the fNIRS signal from each distinct stimulus velocity. The results are inconclusive regarding the velocity which evokes the highest intensity of hemodynamic response

Audience synchronies in live concerts illustrate the embodiment of music experience

A study of 132 audience members of three classical public concerts (all three staged the same chamber music pieces by Ludwig van Beethoven, Brett Dean, and Johannes Brahms) had the goal of analyzing the physiological and motor responses of audiences. It was assumed that the music would induce synchronous physiology and movement in listeners (induction synchrony). In addition to hypothesizing that such synchronies would be present, we expected that they were linked to participants' aesthetic experiences, their affect and personality traits, which were assessed by questionnaires before and after the concerts. Clear evidence was found of physiological synchrony (heart rate, respiration rate, skin conductance response) as well as movement synchrony of the audiences, whereas breathing behavior was not synchronized. Thus the audiences of the three concerts resonated with the music, their music perception was embodied. There were links between the bodily synchrony and aesthetic experiences: synchrony, especially heart-rate synchrony, was higher when listeners felt moved emotionally and inspired by a piece, and were immersed in the music. Personality traits were also associated with the individual contributions to induction synchrony

Neuropeptidergic Signaling Partitions Arousal Behaviors in Zebrafish

Animals modulate their arousal state to ensure that their sensory responsiveness and locomotor activity match environmental demands. Neuropeptides can regulate arousal, but studies of their roles in vertebrates have been constrained by the vast array of neuropeptides and their pleiotropic effects. To overcome these limitations, we systematically dissected the neuropeptidergic modulation of arousal in larval zebrafish. We quantified spontaneous locomotor activity and responsiveness to sensory stimuli after genetically induced expression of seven evolutionarily conserved neuropeptides, including adenylate cyclase activating polypeptide 1b (adcyap1b), cocaine-related and amphetamine-related transcript (cart), cholecystokinin (cck), calcitonin gene-related peptide (cgrp), galanin, hypocretin, and nociceptin. Our study reveals that arousal behaviors are dissociable: neuropeptide expression uncoupled spontaneous activity from sensory responsiveness, and uncovered modality-specific effects upon sensory responsiveness. Principal components analysis and phenotypic clustering revealed both shared and divergent features of neuropeptidergic functions: hypocretin and cgrp stimulated spontaneous locomotor activity, whereas galanin and nociceptin attenuated these behaviors. In contrast, cart and adcyap1b enhanced sensory responsiveness yet had minimal impacts on spontaneous activity, and cck expression induced the opposite effects. Furthermore, hypocretin and nociceptin induced modality-specific differences in responsiveness to changes in illumination. Our study provides the first systematic and high-throughput analysis of neuropeptidergic modulation of arousal, demonstrates that arousal can be partitioned into independent behavioral components, and reveals novel and conserved functions of neuropeptides in regulating arousal

Inequalities in the distribution of COVID-19-related financial difficulties for Australian families with young children

BACKGROUND: We examine (1) the frequency of financial difficulties in Australian families with young children (0-8 years) in the early and later phases of the pandemic; (2) the extent to which parents' pre-pandemic socio-economic disadvantage (SED) predicted financial difficulties; and (3) whether grandparent intergenerational SED further amplified this risk. METHOD: Data: Australian Temperament Project (ATP; established 1983, N = 2443) and ATP Generation 3 study (ATPG3; established 2012; N = 702), of which 74% (N = 553) completed a COVID-specific module in the early (May-September 2020) and/or later (October-December 2021) phases of the pandemic. OUTCOMES: Parent-reported loss of employment/reduced income, difficulty paying for essentials, and financial strain. EXPOSURES: Pre-pandemic parent and grandparent education and occupation. ANALYSIS: Logistic regressions, estimated via generalized estimating equations, were used to examine associations between the pre-pandemic SED of parents and grandparents and their interaction with financial difficulties, adjusting for potential confounders. RESULTS: At both pandemic time points, a third of parents reported adverse financial impacts (early: 34%, 95% confidence interval [CI] = 30-38; later: 32%, 95% CI = 28-36). Each standard deviation increase in the parents' pre-pandemic SED was associated with a 36% increase in the odds of reporting multiple financial difficulties (odds ratio [OR] = 1.36, 95% CI = 1.04-1.78). There was little evidence of an interaction between the SED of parents and grandparents. CONCLUSIONS: Financial impacts related to the COVID-19 pandemic were common and, irrespective of grandparent SED, disproportionately borne by parents with higher pre-pandemic SED. Given the well-established relationship between disadvantage and child health and development, sustained and well-targeted government supports will be critical to minimizing adverse impacts in years to come

Effects of Calcium β-HMB Supplementation During Training on Markers of Catabolism, Body Composition, Strength and Sprint Performance

Calcium β-hydroxy β-methylbutyrate (HMB) supplementation has been reported to reduce catabolism and promote gains in strength and fat free mass in untrained individuals initiating training. However, the effects of HMB supplementation on strength and body composition alterations during training in athletes is less clear. This study examined the effects of 28-d of calcium HMB supplementation during intense training on markers of catabolism, body composition, strength, and sprint performance. In a double-blind and randomized manner, 28 NCAA division I-A football players were matched-paired and assigned to supplement their diet for 28-d during winter resistance/agility training (~8 hr/wk) with a carbohydrate placebo supplement (P) or the P supplement with 3 g/day of HMB as a calcium salt (HMB). Prior to and following supplementation: dietary records and fasting blood samples were obtained; body composition was determined via DEXA; subjects performed maximal effort bench press, barbell back squat, and power clean isotonic repetition tests; and, subjects performed a repeated cycle ergometer sprint test (12 x 6-s sprints with 30-s rest recovery) to simulate a 12-play drive in football. Results revealed no significant differences between the placebo and HMB supplemented groups in markers of catabolism, muscle/liver enzyme efflux, hematological parameters, body composition, combined lifting volume, or repetitive sprint performance. Results indicate that HMB supplementation (3 g/day) during off-season college football resistance/agility training does not reduce catabolism or provide ergogenic benefit

Self-assembly under confinement: nanocorrals for understanding fundamentals of 2D crystallization

Nanocorrals with different size, shape, and orientation are created on covalently modified highly oriented pyrolytic graphite surfaces using scanning probe nanolithography, i.e., nanoshaving. Alkylated diacetylene molecules undergo laterally confined supramolecular self-assembly within these corrals. When nanoshaving is performed in situ, at the liquid–solid interface, the orientation of the supramolecular lamellae structure is directionally influenced by the gradual graphite surface exposure. Careful choice of the nanoshaving direction with respect to the substrate symmetry axes promotes alignment of the supramolecular lamellae within the corral. Self-assembly occurring inside corrals of different size and shape reveals the importance of geometric and kinetic constraints controlled by the nanoshaving process. Finally, seed-mediated crystallization studies demonstrate confinement control over nucleation and growth principles