Design of a Monolithic Compliant Swimming Robot

Compliant mechanisms use the flexibility of their members to transfer an input displacement, force or torque to another point on the mechanism through the large deformation of its flexible links or joints. Fewer number of links, no friction, no backlash and simple design are the most important features that make them an ideal candidate when light weight, low cost and high performance are desired. The only challenge while designing a compliant mechanism is deriving the equations of motion as flexible links or flexure hinges go under large deformation. We designed a monolithic compliant swimming robot consists of a dc motor, flexible links, rigid crank, ball bearing and a base. The crank is connected to the motor using the ball bearing. The tail is designed as a lumped compliant mechanism in which the elastic deformation concentrates more on the flexure hinges to mimic the fish tail. As the motor is actuated and crank starts rotating, the flexible link attached to the crank actuates the rigid link. Rigid link is also coupled with flexure hinges to restrict its motion to tail back and forth in the water. Mechanism cad model is created, and motion analysis are performed both in Solidworks and Adams View. The entire mechanism is 3D printed using PETG filament and preliminary results are obtained from experimental testing. It’s been observed that mechanism successfully swims in the forward direction through the deformation of the flexible links and tail. The next steps will be the investigation of other actuation methods such as magnets or shape memory alloy wires and control of motion using Arduino nano so that the swimming robot will follow a desired trajectory

Effective-periodicity effects in Fibonacci slot arrays

In this Letter, the transmission properties of a nonperiodic array of slots arranged in the form of a Fibonacci sequence are investigated. By arranging the slots in this manner, an additional periodicity can be utilized, resulting in corresponding resonance features in the transmitted signal. By investigating the transmission response of a perforated metallic sheet over a broad frequency range (6–40 GHz), it is shown that this simple one-dimensional chain supports two periodicities, one due to the regular periodic separation and one due to average spacing—which is related to the golden ratio. This response replicates the resonant behavior of a two-dimensional periodic array with a single nonperiodic array also creating new families of diffraction lobes in the far-field region.MCIN/AEI/10.13039/501100011033 PID2020-116739GB-I00EPSRC EP/R004781/1EPSRC EP/L015331/

Malignant Acute Disseminated Encephalomyelitis (ADEM) Presenting as a Stroke Alert: A Case Report.

Acute disseminated encephalomyelitis (ADEM) is a rare illness. Generally characterized by encephalopathy and non-specific, heterogeneous neurological deficits depending on the location of the demyelinated lesions, ADEM is considered a clinical diagnosis with radiological findings that may or may not have supportive features based on the temporal relationship of an inciting factor and symptom onset. Even rarer, hyperacute or malignant ADEM can be defined by rapid symptom onset followed by catastrophic brain edema and its sequelae. We present a case of a patient who presented with an acute stroke with activation of a rapid sequence care pathway (stroke alert protocol) to mobilize resources that could expedite his care to determine eligibility for thrombolysis. ADEM was the definitive diagnosis with a subsequent rapid and treatment-refractory decline

TeV String State Excitation via High Energy Cosmic Neutrinos

We construct the open-string scattering amplitudes for neutrino-gluon collisions and evaluate the high energy neutrino-nucleon scattering cross section via string state excitations in the TeV string-scale scenario. We find that the neutrino-gluon scattering is the dominant contribution, 5-10 times larger than neutrino-quark processes, though black hole production may be larger than the string contribution at higher energies. We illustrate the observability of the string signal at the Auger Observatory and the IceCube neutrino telescope for a string scale about 1 TeV.Comment: version to appear in PL

Netrin-3 Signals Through Serine Phosphorylation in Tetrahymena thermophila

The netrin family of proteins are structurally related to laminin and, while first discovered in the nematode Caenorhabditis elegans, are now known to be present in species throughout the animal kingdom, including humans. These proteins also have a wide variety of roles that include inhibition of apoptosis, chemorepulsion, and axonal guidance. Due to the results of previous studies involving netrin-1 in vertebrate systems, the current prevailing assumption is that netrins, when acting as chemorepellents, signal using tyrosine kinases. However, data that we gathered through phosphoserine-targeting ELISA assays and immunofluorescence microscopy demonstrates that the netrin-3 peptides signal Tetrahymena thermophila through serine phosphorylation instead, causing the ciliate protists to avoid netrin-3 peptides in response. Treatment with netrin-3 peptides also seems to cause mitotic inhibition in Tetrahymena, which can be reversed by addition of a serine kinase inhibitor. This new information suggests that netrin-3 may have physiological roles that have previously been unexplored

Gram-Negative Bacterial Infections: Research Priorities, Accomplishments, and Future Directions of the Antibacterial Resistance Leadership Group

Antimicrobial resistance in pathogenic gram-negative bacteria is one of the most pressing challenges in the field of infectious diseases and is one of 4 key areas of unmet medical need identified by the Antibacterial Resistance Leadership Group (ARLG). The mission of the Gram-Negative Committee is to advance our knowledge of these challenging infections and implement studies to improve patient outcomes. Studies have fallen primarily into 2 broad categories: prospective cohort studies and interventional trials. Among the observational studies, CRACKLE (Consortium on Resistance Against Carbapenems in Klebsiella pneumoniae and Other Enterobacteriaceae) has contributed seminal multicenter data describing risk factors and clinical outcomes of carbapenem-resistant Enterobacteriaceae (CRE) in sentinel US hospitals. Building on this success, CRACKLE II will expand the network to hospitals across the United States and Colombia. Similar protocols have been proposed to include Acinetobacter baumannii and Pseudomonas aeruginosa (SNAP and POP studies). In addition, the CREST study (Carbapenem-Resistant Enterobacteriaceae in Solid Organ Transplant Patients) has provided pivotal data on extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae and CRE carriage among solid organ transplant recipients to inform management of this vulnerable patient population. Two clinical trials to define novel ways of using an existing antibiotic, fosfomycin, to treat ESBL-producing Enterobacteriaceae (one that has completed enrollment and the other in late protocol development) will determine the clinical efficacy of fosfomycin as step-down oral therapy to treat complicated urinary tract infections. Additional clinical studies and trials using immunotherapeutic or newly approved agents are also in the planning stage, with the main goals of generating actionable data that will inform clinical decision making and facilitate development of new treatment options for highly resistant gram-negative bacterial infections

Association of blood pressure variability and neurocognition in children with chronic kidney disease

Children with chronic kidney disease (CKD) and hypertension have increased blood pressure variability (BPV). Increased BPV has been associated with lower neurocognitive test scores in adults. Children with CKD are at risk for decreased neurocognitive function. Our objective was to determine if children with CKD and increased BPV had worse performance on neurocognitive testing compared with children with CKD and lower BPV

α-Synuclein Aggregation Inhibitory Prunolides and a Dibrominated β-Carboline Sulfamate from the Ascidian Synoicum prunum

Seven new polyaromatic bis-spiroketal-containing butenolides, the prunolides D–I (4–9) and cis-prunolide C (10), a new dibrominated β-carboline sulfamate named pityriacitrin C (11), alongside the known prunolides A–C (1–3) were isolated from the Australian colonial ascidian Synoicum prunum. The prunolides D–G (4–7) represent the first asymmetrically brominated prunolides, while cis-prunolide C (10) is the first reported with a cis-configuration about the prunolide’s bis-spiroketal core. The prunolides displayed binding activities with the Parkinson’s disease-implicated amyloid protein α-synuclein in a mass spectrometry binding assay, while the prunolides (1–5 and 10) were found to significantly inhibit the aggregation (>89.0%) of α-synuclein in a ThT amyloid dye assay. The prunolides A–C (1–3) were also tested for inhibition of pSyn aggregate formation in a primary embryonic mouse midbrain dopamine neuron model with prunolide B (2) displaying statistically significant inhibitory activity at 0.5 μM. The antiplasmodial and antibacterial activities of the isolates were also examined with prunolide C (3) displaying only weak activity against the 3D7 parasite strain of Plasmodium falciparum. Our findings reported herein suggest that the prunolides could provide a novel scaffold for the exploration of future therapeutics aimed at inhibiting amyloid protein aggregation and the treatment of numerous neurodegenerative diseases.Peer reviewe

Neurocognitive Function in Children with Primary Hypertension

To compare neurocognitive test performance of children with primary hypertension to that of normotensive controls

Multiple marker abundance profiling:combining selected reaction monitoring and data-dependent acquisition for rapid estimation of organelle abundance in subcellular samples

Measuring changes in protein or organelle abundance in the cell is an essential, but challenging aspect of cell biology. Frequently-used methods for determining organelle abundance typically rely on detection of a very few marker proteins, so are unsatisfactory. In silico estimates of protein abundances from publicly available protein spectra can provide useful standard abundance values but contain only data from tissue proteomes, and are not coupled to organelle localization data. A new protein abundance score, the normalized protein abundance scale (NPAS), expands on the number of scored proteins and the scoring accuracy of lower-abundance proteins in Arabidopsis. NPAS was combined with subcellular protein localization data, facilitating quantitative estimations of organelle abundance during routine experimental procedures. A suite of targeted proteomics markers for subcellular compartment markers was developed, enabling independent verification of in silico estimates for relative organelle abundance. Estimation of relative organelle abundance was found to be reproducible and consistent over a range of tissues and growth conditions. In silico abundance estimations and localization data have been combined into an online tool, multiple marker abundance profiling, available in the SUBA4 toolbox (http://suba.live)