Real time digital control and controlled structures experiments

Viewgraphs covering the following topics are given: controlled structures technology at Grumman Corporate Research Center, active and passive control technology, experiment plans, and vacuum chamber test experiment objectives and setup

Application of piezoelectric actuators to active control of composite spherical caps

Abstract. Dynamics of reinforced shallow spherical caps is considered in this paper. The cap is subjected to a uniform dynamic pressure that results in a globally axisymmetric motion. The reduction of amplitudes and stresses is achieved by using pairs of piezoelectric actuators bonded to the meridional stiffeners (one of the actuators can be bonded to the inner surface of the skin). These pairs of actuators produce dynamic couples that can reduce the amplitude of motion. The analysis is based on the theory of shallow shells (Donnell-Mushtari-Vlasov theory) using a smeared stiffeners technique. The analytical solution is generated for a cap clamped along the boundary using the approximation of the meridional curve suggested by Huang. Numerical results illustrate the feasibility of a significant reduction of deflections and stresses using piezoelectric actuators with weight and energy consumption acceptable in practical design

Is Foundational Movement Skill Competency Important for Keeping Children Physically Active and at a Healthy Weight?

This longitudinal study examines the associations between foundational movement skills (FMS) competency, moderate-to-vigorous physical activity (MVPA) and weight status among children (n = 75) attending preschools in deprived areas from early to late childhood. Twelve FMS were assessed using the Children’s Activity and Movement in Preschool Motor Skills Protocol and video analysis. Physical activity was measured via hip-mounted accelerometry. Data was collected over a five-year period, with Baseline Follow Up data collected between 2010 and 2015. There was an overall pattern of increase for total, object-control and locomotor scores between Baseline and Follow-Up. Conversely, there was an overall pattern of decline for MVPA among participants. There was a positive significant (p < 0.05) association between total and locomotor scores and MVPA at Baseline. However, these associations weakened over time and no significant associations were found at Follow-Up. Baseline competency failed to predict Follow-Up MVPA or weight status. Likewise, Baseline MVPA was not found to be a predictor of Follow-Up FMS competency. Further longitudinal research is required to explore these associations among children from highly deprived areas. Future interventions may require a more holistic approach to improving FMS competency and increasing PA in order to account for the number of variables that can affect these outcomes

Direct quantum dynamics using variational Gaussian wavepackets and Gaussian process regression

The method of direct variational quantum nuclear dynamics in a basis of Gaussian wavepackets, combined with the potential energy surfaces fitted on-the-fly using Gaussian process regression, is described together with its implementation. Enabling exact and efficient analytic evaluation of Hamiltonian matrix elements, this approach allows for black-box quantum dynamics of multidimensional anharmonic molecular systems. Example calculations of intra-molecular proton transfer on the electronic ground state of salicylaldimine are provided, and future algorithmic improvements as well as the potential for multiple-state non-adiabatic dynamics are discussed

Expression of p16 Within Myenteric Neurons of the Aged Colon: A Potential Marker of Declining Function.

Human colonic neuromuscular functions decline among the elderly. The aim was to explore the involvement of senescence. A preliminary PCR study looked for age-dependent differences in expression of CDKN1A (encoding the senescence-related p21 protein) and CDKN2A (encoding p16 and p14) in human ascending and descending colon (without mucosa) from 39 (approximately 50: 50 male: female) adult (aged 27-60 years) and elderly donors (70-89 years). Other genes from different aging pathways (e.g., inflammation, oxidative stress, autophagy) and cell-types (e.g., neurons, neuron axonal transport) were also examined. Unlike CDKN1A, CDKN2A (using primers for p16 and p14 but not when using p14-specific primers) was upregulated in both regions of colon. Compared with the number of genes appearing to upregulate in association with temporal age, more genes positively associated with increased CDKN2A expression (respectively, 16 and five of 44 genes studied for ascending and descending colon). Confirmation of increased expression of CDKN2A was sought by immunostaining for p16 in the myenteric plexus of colon from 52 patients, using a semi-automated software protocol. The results showed increased staining not within the glial cells (S100 stained), but in the cytoplasm of myenteric nerve cell bodies (MAP2 stained, with identified nucleus) of ascending, but not descending colon of the elderly, and not in the cell nucleus of either region or age group (5,710 neurons analyzed: n = 12-14 for each group). It was concluded that increased p16 staining within the cytoplasm of myenteric nerve cell bodies of elderly ascending (but not descending) colon, suggests a region-dependent, post-mitotic cellular senescence-like activity, perhaps involved with aging of enteric neurons within the colon

Sol-gel synthesis of quaternary (P2O5)(55)-(CaO)(25)-(Na2O)((20-x))-(TiO2)(x) bioresorbable glasses for bone tissue engineering applications (x=0, 5, 10, or 15)

In the present study, we report a new and facile sol–gel synthesis of phosphate-based glasses with the general formula of (P2O5)55–(CaO)25–(Na2O)(20−x)–(TiO2) x , where x = 0, 5, 10 or 15, for bone tissue engineering applications. The sol–gel synthesis method allows greater control over glass morphology at relatively low processing temperature (200 °C) in comparison with phosphate-based melt-derived glasses (~1000 °C). The glasses were analyzed using several characterization techniques, including x-ray diffraction (XRD), 31P magic angle spinning nuclear magnetic resonance (31P MAS-NMR), Fourier transform infrared (FTIR) spectroscopy and energy-dispersive x-ray (EDX) spectroscopy, which confirmed the amorphous and glassy nature of the prepared samples. Degradation was assessed by measuring the ion release and pH change of the storage medium. Cytocompatibility was also confirmed by culturing osteoblast-like osteosarcoma cell line MG-63 on the glass microparticles over a seven-day period. Cell attachment to the particles was imaged using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The results revealed the potential of phosphate-based sol–gel derived glasses containing 5 or 10 mol% TiO2, with high surface area, ideal dissolution rate for cell attachment and easily metabolized dissolution products, for bone tissue engineering applications

Functional and anatomical deficits in visceral nociception with age: a mechanism of silent appendicitis in the elderly?

The ability to sense visceral pain during appendicitis is diminished with age leading to delay in seeking health care and poorer clinical outcomes. To understand the mechanistic basis of this phenomenon, we examined visceral nociception in aged mouse and human tissue. Inflamed and noninflamed appendixes were collected from consenting patients undergoing surgery for the treatment of appendicitis or bowel cancer. Supernatants were generated by incubating samples in buffer and used to stimulate multiunit activity in intestinal preparations, or single-unit activity from teased fibres in colonic preparations, of young and old mice. Changes in afferent innervation with age were determined by measuring the density of calcitonin gene-related peptide-positive afferent fibres and by counting dorsal root ganglia back-labelled by injection of tracer dye into the wall of the colon. Finally, the effect of age on nociceptor function was studied in mouse and human colon. Afferent responses to appendicitis supernatants were greatly impaired in old mice. Further investigation revealed this was due to a marked reduction in the afferent innervation of the bowel and a substantial impairment in the ability of the remaining afferent fibres to transduce noxious stimuli. Translational studies in human tissue demonstrated a significant reduction in the multiunit but not the single-unit colonic mesenteric nerve response to capsaicin with age, indicative of a loss of nociceptor innervation. Our data demonstrate that anatomical and functional deficits in nociception occur with age, underpinning the atypical or silent presentation of appendicitis in the elderly

An octameric PqiC toroid stabilises the outer-membrane interaction of the PqiABC transport system

The E. coli Paraquat Inducible (Pqi) Pathway is a putative Gram-negative phospholipid transport system. The pathway comprises three components: an integral inner membrane protein (PqiA), a periplasmic spanning MCE family protein (PqiB) and an outer membrane lipoprotein (PqiC). Interactions between all complex components, including stoichiometry, remain uncharacterised; nevertheless, once assembled into their quaternary complex, the trio of Pqi proteins are anticipated to provide a continuous channel between the inner and outer membranes of diderms. Here, we present X-ray structures of both the native and a truncated, soluble construct of the PqiC lipoprotein, providing insight into its biological assembly, and utilise neutron reflectometry to characterise the nature of the PqiB-PqiC-membrane interaction. Finally, we employ phenotypic complementation assays to probe specific PqiC residues, which imply the interaction between PqiB and PqiC is less intimate than previously anticipated.</p

ToTem: A phase Ib trial of temisirolimus with gemcitabine and cisplatin.

Background: gemcitabine (G) and cisplatin (C) is a standard-of-care, combination chemotherapy regimen for neoadjuvant treatment of muscle-invasive and palliative treatment of advanced bladder cancer (BC). More effective regimens are urgently needed, with no significant improvements on GC in more than a decade. Mammalian target of rapamycin (mTOR) is a rational target for BC therapy, as abnormalities are commonly seen in mTOR’s upstream activators/downstream effectors in the PI3K/AKT/mTOR signaling pathway. We therefore performed a Phase Ib trial, combining escalating doses of the mTOR inhibitor, temsirolimus (T) with GC. Methods: following regulatory and ethical approvals, eligible patients with advanced malignancy were treated with one or more doses of intravenous (IV) T plus fixed doses of IV GC in a 21-day (d) cycle. Previous unpublished data suggest a possible interaction between G and T. We therefore pursued a cautious escalation strategy (see table), as a precaution against excessive toxicity. Results: 14 patients (3 BC, 2 lung, 2 ovarian, 7 other cancers; 7 previous platinum exposure) were treated, at 4 dose schedules in 2 UK centers. There were no treatment-related deaths or SUSARs. Of 14 SAEs, 4 were SARs, in 10 individuals, 7 of whom had received IMP. Addition of 10mg T on d15, then d8&15 was tolerated, but DLTs were encountered when administering three 10mg doses of T, both on d1,8&15 (neutropenia; hypokalaemia) and d2,9&15 (febrile neutropenia; rash). T was omitted because of myelosuppression on d15, cycle 1 in 6/8 patients scheduled to receive 3 doses of T. Conclusions: it has not been feasible to add three, weekly doses of T to GC, even at low T doses, in the patient group tested, because of predominantly hematological toxicity. We plan to amend the schedule to include two doses of T, on d2&9, informed by data from pre-planned PK analyses of patients already treated. ToTem was developed by the UK NCRI Bladder Cancer Clinical Studies Group, sponsored by Cardiff University, funded by Cancer Research UK, and supported by supply of free drug and distribution costs from Pfizer. Clinical trial information: 31546330

Ex vivo study of human visceral nociceptors.

OBJECTIVE: The development of effective visceral analgesics free of deleterious gut-specific side effects is a priority. We aimed to develop a reproducible methodology to study visceral nociception in human tissue that could aid future target identification and drug evaluation. DESIGN: Electrophysiological (single unit) responses of visceral afferents to mechanical (von Frey hair (VFH) and stretch) and chemical (bradykinin and ATP) stimuli were examined. Thus, serosal afferents (putative nociceptors) were used to investigate the effect of tegaserod, and transient receptor potential channel, vanilloid 4 (TRPV4) modulation on mechanical responses. RESULTS: Two distinct afferent fibre populations, serosal (n=23) and muscular (n=21), were distinguished based on their differences in sensitivity to VFH probing and tissue stretch. Serosal units displayed sensitivity to key algesic mediators, bradykinin (6/14 units tested) and ATP (4/10), consistent with a role as polymodal nociceptors, while muscular afferents are largely insensitive to bradykinin (0/11) and ATP (1/10). Serosal nociceptor mechanosensitivity was attenuated by tegaserod (-20.8±6.9%, n=6, p<0.05), a treatment for IBS, or application of HC067047 (-34.9±10.0%, n=7, p<0.05), a TRPV4 antagonist, highlighting the utility of the preparation to examine the mechanistic action of existing drugs or novel analgesics. Repeated application of bradykinin or ATP produced consistent afferent responses following desensitisation to the first application, demonstrating their utility as test stimuli to evaluate analgesic activity. CONCLUSIONS: Functionally distinct subpopulations of human visceral afferents can be demonstrated and could provide a platform technology to further study nociception in human tissue