Some critical remarks on a new numerical method for simulation of dynamical systems

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68690/2/10.1177_003754976600600210.pd

Integration of robotic systems in a packaging machine: A tool for design and simulation of efficient motion trajectories

In this paper, the advantages of CACSD (Computer Aided Control System Design) tools for integrating a robotic system in a packaging machine are illustrated. Beside the mechanical integration of the robot into the machine architecture, it is necessary a functional integration, that requires a precise synchronization with the other parts of the system. In the proposed application, a robot with a parallel kinematics is used for pick-and-place tasks between two conveyor belts. It is therefore necessary a proper motion planning which allows to synchronize the grasp and release phases with the conveyor belts, avoiding obstacles and guaranteeing the compliance with bounds on velocity, acceleration and limits in the workspace. A trajectory composed by quintic polynomials has been considered and a specific tool has been designed in the Matlab environment, which allows to modify the parameters of the trajectory and to analyze the obtained motion profiles from both the kinematic and dynamic point of view

Gold nanoparticles supported on functionalized silica as catalysts for alkyne hydroamination: A chemico-physical insight

Highly stable gold nanoparticles anchored on propynylcarbamate-functionalized silica (Au/SiO2@Yne) have been efficiently utilized for the heterogeneous hydroamination of phenylacetylene with aniline under different reaction conditions. In order to ascertain the eventual influence of surface silanol groups on the system activity and selectivity tailored modifications of Au/SiO2@Yne catalysts were pursued according to two different strategies, involving respectively functionalization with trimethylethoxysilane (Au/SiO2@Yne-TMS) or post-treatment with triethylamine (Au/SiO2@Yne-NEt3). The prepared materials were analysed by several complementary techniques such as Solid State NMR (SS NMR), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD). A comparison of the resulting catalytic activities with that of the pristine Au/SiO2@Yne revealed a significant improvement for Au/SiO2@Yne-NEt3 in terms of both conversion and selectivity. Recycling and stability studies showed a catalytic activity decrease after the first run, due to the formation of polyphenylacetylene (PPhA) oligomers shielding the active sites. PPhA removal by sonication in acetone fully restored the catalytic activity and empowered the system with a good operational stability, a very crucial issue in view of eventual practical applications

Cytochalasin B Influences Cytoskeletal Organization and Osteogenic Potential of Human Wharton’s Jelly Mesenchymal Stem Cells

Among perinatal stem cells of the umbilical cord, human Wharton’s jelly mesenchymal stem cells (hWJ-MSCs) are of great interest for cell-based therapy approaches in regenerative medicine, showing some advantages over other MSCs. In fact, hWJ-MSCs, placed between embryonic and adult MSCs, are not tumorigenic and are harvested with few ethical concerns. Furthermore, these cells can be easily cultured in vitro, maintaining both stem properties and a high proliferative rate for several passages, as well as trilineage capacity of differentiation. Recently, it has been demonstrated that cytoskeletal organization influences stem cell biology. Among molecules able to modulate its dynamics, Cytochalasin B (CB), a cyto-permeable mycotoxin, influences actin microfilament polymerization, thus affecting several cell properties, such as the ability of MSCs to differentiate towards a specific commitment. Here, we investigated for the first time the effects of a 24 h-treatment with CB at different concentrations (0.1–3 μM) on hWJ-MSCs. CB influenced the cytoskeletal organization in a dose-dependent manner, inducing changes in cell number, proliferation, shape, and nanomechanical properties, thus promoting the osteogenic commitment of hWJ-MSCs, as confirmed by the expression analysis of osteogenic/autophagy markers

Evolution of enhanced innate immune evasion by SARS-CoV-2

Emergence of SARS-CoV-2 variants of concern (VOCs) suggests viral adaptation to enhance human-to-human transmission1,2. Although much effort has focused on characterisation of spike changes in VOCs, mutations outside spike likely contribute to adaptation. Here we used unbiased abundance proteomics, phosphoproteomics, RNAseq and viral replication assays to show that isolates of the Alpha (B.1.1.7) variant3 more effectively suppress innate immune responses in airway epithelial cells, compared to first wave isolates. We found that Alpha has dramatically increased subgenomic RNA and protein levels of N, Orf9b and Orf6, all known innate immune antagonists. Expression of Orf9b alone suppressed the innate immune response through interaction with TOM70, a mitochondrial protein required for RNA sensing adaptor MAVS activation. Moreover, the activity of Orf9b and its association with TOM70 was regulated by phosphorylation. We propose that more effective innate immune suppression, through enhanced expression of specific viral antagonist proteins, increases the likelihood of successful Alpha transmission, and may increase in vivo replication and duration of infection4. The importance of mutations outside Spike in adaptation of SARS-CoV-2 to humans is underscored by the observation that similar mutations exist in the Delta and Omicron N/Orf9b regulatory regions

The potential of AFM in studying the role of the nanoscale amphipathic nature of (lipo)-peptides interacting with lipid bilayers

Antimicrobial peptides (AMPs) and lipopeptides (LPs) represent very promising molecules to fight resistant bacterial infections due to their broad-spectrum of activity, their first target, i.e. the bacterial membrane, and the rapid bactericidal action. For both types of molecules, the action mechanism starts from the membrane of the pathogen agents, producing a disorganization of their phase structure or the formation of pores of different size altering their permeability. This mechanism of action is based on physical interactions more than on a lock-and-key recognition event and it is difficult for the pathogens to rapidly develop an effective resistance. Very small differences in the sequence of both AMPs and LPs might lead to very different effects on the target membrane. Therefore, a correct understanding of their mechanism of action is required with the aim of developing new synthetic peptides, analogues of the natural ones, with specific and more powerful bactericidal activity. Atomic force microscopy (AFM), with its high resolution and the associated force spectroscopy resource, provides a valuable technique to investigate the reorganization of lipid bilayers exposed to antimicrobial or lipopeptides. Here, we present AFM results obtained by ours and other groups on the action of AMPs and LPs on supported lipid bilayers (SLBs) of different composition. We also consider data obtained by fluorescence microscopy to compare the AFM data with another technique which can be used on different lipid bilayer model systems such as SLBs and giant unilamellar vesicles. The outcomes here presented highlight the powerful of AFM-based techniques in detecting nanoscale peptide-membrane interactions and strengthen their use as an exceptional complementary tool to in vivo investigations. Indeed, the combination of these approaches can help decipher the mechanisms of action of different antimicrobials and lipopeptides at both the micro and nanoscale levels, and to design new and more efficient antimicrobial compounds

Life at Home in the Twenty-First Century: 32 Families Open Their Doors

Life at Home in the Twenty-First Century cross-cuts the ranks of important books on social history, consumerism, contemporary culture, the meaning of material culture, domestic architecture, and household ethnoarchaeology. Far richer in information and more incisive than America at Home (Smolan and Erwitt), this innovative book also moves well beyond Rick Smolan's Day in the Life series. It is a distant cousin of Material World and Hungry Planet in content and style, but represents a blend of rigorous science and photography that none of these titles can claim. The authors are widely published scholars--archaeologists and anthropologists from UCLA--and a world-renowned photographer. Using archaeological approaches to human material culture, this volume offers unprecedented access to the middle-class American home through the kaleidoscopic lens of no-limits photography and many kinds of never-before acquired data about how people actually live their lives at home. Its foundation is a meticulous, 10-year study of 32 ordinary Californian middle-class families. Extensive media coverage shows it has strong appeal not only to scientists but also to the book-buying public, people who share intense curiosity about what goes on at home in their neighborhoods. Many who read the book will see their own lives mirrored in these pages and can reflect on how other people cope with their mountains of possessions and other daily challenges. Readers abroad will be equally fascinated by the contrasts between their own kinds of materialism and the typical American experience, as a sample of Italians' and Swedes' responses to the photographs and findings have demonstrated. The book will interest a range of designers, builders, and architects as well as scholars and students who research various facets of U.S. and global consumerism, cultural history, and economic history