Static Balancing of Wheeled-legged Hexapod Robots

Locomotion over different terrain types, whether flat or uneven, is very important for a wide range of service operations in robotics. Potential applications range from surveillance, rescue, or hospital assistance. Wheeled-legged hexapod robots have been designed to solve these locomotion tasks. Given the wide range of feasible operations, one of the key operation planning issues is related to the robot balancing during motion tasks. Usually this problem is related with the pose of the robot’s center of mass, which can be addressed using different mathematical techniques. This paper proposes a new practical technique for balancing wheeled-legged hexapod robots, where a Biodex Balance System model SD (for static & dynamic) is used to obtain the effective position of the center of mass, thus it can be recalculated to its optimal position. Experimental tests are carried out to evaluate the effectiveness of this technique and modify and improve the position of hexapod robots’ center of mass.

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The Effect of Water-Based Therapy Compared to Land-Based Therapy on Balance and Gait Parameters of Patients with Stroke: A Systematic Review

European Neurology ◽

10.1159/000517377 ◽

2021 ◽

pp. 1-9

Author(s):

Nour Zughbor ◽

Aisha Alwahshi ◽

Rahaf Abdelrahman ◽

Zeina Elnekiti ◽

Hoda Elkareish ◽

...

Keyword(s):

Meta Analysis ◽

Berg Balance Scale ◽

Primary Outcome Measure ◽

Balance System ◽

Effect Of Water ◽

Gait Parameters ◽

Water Based ◽

Biodex Balance System ◽

Therapy Studies ◽

The Brain

Introduction: Stroke is defined as the lack of blood supply to the brain, leading to rapid loss of brain function presenting with impairments such as muscle weakness, spasticity, lack of coordination, and proprioception loss. Both hydrotherapy and land-based therapy aim to target these aspects in the process of rehabilitation. The study aims to determine the effectiveness of water-based therapy on balance and gait of patients with stroke compared to land-based therapy. Methods: Data for this review were extracted from databases such as CINAHL, OTseeker, Ovid, PEDro, and PubMed (MEDLINE) and other sources such as Google Scholar. PRISMA guidelines were followed to exclude irrelevant studies. Only randomized controlled trials (RCTs) were included, and methodological quality was assessed using the PEDro scale. A meta-analysis of extracted data was conducted. Results: A total of 16 relevant RCTs were included for the review (n = 412 participants). All RCTs investigated the effect of water-based therapy compared to land-based therapy on balance and gait of patients with stroke. Meta-analysis of studies that used the Berg Balance Scale (BBS) as a primary outcome measure favored land-based therapy. Studies that used the Good Balance System (GBS) and the Biodex Balance System (BioBS) to measure the changes in anteroposterior sway and mediolateral sway favored water-based therapy. The overall pooled effect favored land-based therapy in improving gait parameters. Conclusion: Findings from meta-analysis support the effectiveness of land-based therapy in the improvement of balance and gait parameters of patients with stroke. However, the evidence for water-based therapy continues to be limited, and higher quality studies are required to determine the effectiveness of water-based therapy on patients with stroke, particularly on balance and gait.

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A Slot-Die Technique for the Preparation of Continuous, High-Area, Chitosan-Based Thin Films

Polymers ◽

10.3390/polym13101566 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1566

Author(s):

Oliver J. Pemble ◽

Maria Bardosova ◽

Ian M. Povey ◽

Martyn E. Pemble

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

High Volume ◽

Mechanical Anisotropy ◽

Diverse Range ◽

Direction Parallel ◽

High Area ◽

Wide Range ◽

Slot Die ◽

Potential Applications

Chitosan-based films have a diverse range of potential applications but are currently limited in terms of commercial use due to a lack of methods specifically designed to produce thin films in high volumes. To address this limitation directly, hydrogels prepared from chitosan, chitosan-tetraethoxy silane, also known as tetraethyl orthosilicate (TEOS) and chitosan-glutaraldehyde have been used to prepare continuous thin films using a slot-die technique which is described in detail. By way of preliminary analysis of the resulting films for comparison purposes with films made by other methods, the mechanical strength of the films produced was assessed. It was found that as expected, the hybrid films made with TEOS and glutaraldehyde both show a higher yield strength than the films made with chitosan alone. In all cases, the mechanical properties of the films were found to compare very favorably with similar measurements reported in the literature. In order to assess the possible influence of the direction in which the hydrogel passes through the slot-die on the mechanical properties of the films, testing was performed on plain chitosan samples cut in a direction parallel to the direction of travel and perpendicular to this direction. It was found that there was no evidence of any mechanical anisotropy induced by the slot die process. The examples presented here serve to illustrate how the slot-die approach may be used to create high-volume, high-area chitosan-based films cheaply and rapidly. It is suggested that an approach of the type described here may facilitate the use of chitosan-based films for a wide range of important applications.

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Health Benefits of Uses and Applications of Moringa oleifera in Bakery Products

Plants ◽

10.3390/plants10020318 ◽

2021 ◽

Vol 10 (2) ◽

pp. 318

Author(s):

Paula García Milla ◽

Rocío Peñalver ◽

Gema Nieto

Keyword(s):

Moringa Oleifera ◽

Essential Amino Acids ◽

Bakery Products ◽

Unani Medicine ◽

Functional Value ◽

Organoleptic Characteristics ◽

Wide Range ◽

Potential Applications ◽

Medicinal Properties ◽

Excellent Source

Moringa oleifera belongs to the Moringaceae family and is the best known of the native Moringa oleifera genus. For centuries, it has been used as a system of Ayurvedic and Unani medicine and has a wide range of nutritional and bioactive compounds, including proteins, essential amino acids, carbohydrates, lipids, fibre, vitamins, minerals, phenolic compounds, phytosterols and others. These characteristics allow it to have pharmacological properties, including anti-diabetic, anti-inflammatory, anticarcinogenic, antioxidant, cardioprotective, antimicrobial and hepatoprotective properties. The entire Moringa oleifera plant is edible, including its flowers, however, it is not entirely safe, because of compounds that have been found mainly in the root and bark, so the leaf was identified as the safest. Moringa oleifera is recognised as an excellent source of phytochemicals, with potential applications in functional and medicinal food preparations due to its nutritional and medicinal properties; many authors have experimented with incorporating it mainly in biscuits, cakes, brownies, meats, juices and sandwiches. The results are fascinating, as the products increase their nutritional value; however, the concentrations cannot be high, as this affects the organoleptic characteristics of the supplemented products. The aim of this study is to review the application of Moringa oleifera in bakery products, which will allow the creation of new products that improve their nutritional and functional value.

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Sporulation in solventogenic and acetogenic clostridia

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11289-9 ◽

2021 ◽

Author(s):

Mamou Diallo ◽

Servé W. M. Kengen ◽

Ana M. López-Contreras

Keyword(s):

Current Knowledge ◽

Carbon Sources ◽

Cost Effective ◽

Biotechnological Production ◽

Key Points ◽

Wide Range ◽

Potential Applications ◽

A Cell ◽

Sporulation Initiation ◽

Solventogenic Clostridia

AbstractThe Clostridium genus harbors compelling organisms for biotechnological production processes; while acetogenic clostridia can fix C1-compounds to produce acetate and ethanol, solventogenic clostridia can utilize a wide range of carbon sources to produce commercially valuable carboxylic acids, alcohols, and ketones by fermentation. Despite their potential, the conversion by these bacteria of carbohydrates or C1 compounds to alcohols is not cost-effective enough to result in economically viable processes. Engineering solventogenic clostridia by impairing sporulation is one of the investigated approaches to improve solvent productivity. Sporulation is a cell differentiation process triggered in bacteria in response to exposure to environmental stressors. The generated spores are metabolically inactive but resistant to harsh conditions (UV, chemicals, heat, oxygen). In Firmicutes, sporulation has been mainly studied in bacilli and pathogenic clostridia, and our knowledge of sporulation in solvent-producing or acetogenic clostridia is limited. Still, sporulation is an integral part of the cellular physiology of clostridia; thus, understanding the regulation of sporulation and its connection to solvent production may give clues to improve the performance of solventogenic clostridia. This review aims to provide an overview of the triggers, characteristics, and regulatory mechanism of sporulation in solventogenic clostridia. Those are further compared to the current knowledge on sporulation in the industrially relevant acetogenic clostridia. Finally, the potential applications of spores for process improvement are discussed.Key Points• The regulatory network governing sporulation initiation varies in solventogenic clostridia.• Media composition and cell density are the main triggers of sporulation.• Spores can be used to improve the fermentation process.

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Click Chemistry Enabling Covalent and Non-Covalent Modifications of Graphene with (Poly)saccharides

Polymers ◽

10.3390/polym13010142 ◽

2020 ◽

Vol 13 (1) ◽

pp. 142

Author(s):

Hu Li ◽

Raffaello Papadakis

Keyword(s):

Click Chemistry ◽

Life Science ◽

Environmental Applications ◽

Energy Materials ◽

Sensors And Actuators ◽

Polar Solvents ◽

Wide Range ◽

Potential Applications ◽

Covalent Modifications

Graphene is a material with outstanding properties and numerous potential applications in a wide range of research and technology areas, spanning from electronics, energy materials, sensors, and actuators to life-science and many more. However, the insolubility and poor dispersibility of graphene are two major problems hampering its use in certain applications. Tethering mono-, di-, or even poly-saccharides on graphene through click-chemistry is gaining more and more attention as a key modification approach leading to new graphene-based materials (GBM) with improved hydrophilicity and substantial dispersibility in polar solvents, e.g., water. The attachment of (poly)saccharides on graphene further renders the final GBMs biocompatible and could open new routes to novel biomedical and environmental applications. In this review, recent modifications of graphene and other carbon rich materials (CRMs) through click chemistry are reviewed.

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State of the Science in Dried Blood Spots

Clinical Chemistry ◽

10.1373/clinchem.2017.275966 ◽

2018 ◽

Vol 64 (4) ◽

pp. 656-679 ◽

Cited By ~ 51

Author(s):

Jeffrey D Freeman ◽

Lori M Rosman ◽

Jeremy D Ratcliff ◽

Paul T Strickland ◽

David R Graham ◽

...

Keyword(s):

Systematic Approach ◽

Full Range ◽

Dried Blood Spots ◽

Blood Spots ◽

Highly Sensitive ◽

Wide Range ◽

Potential Applications ◽

Review Of Reviews ◽

Near Term ◽

State Of The Science

Abstract BACKGROUND Advancements in the quality and availability of highly sensitive analytical instrumentation and methodologies have led to increased interest in the use of microsamples. Among microsamples, dried blood spots (DBS) are the most well-known. Although there have been a variety of review papers published on DBS, there has been no attempt at describing the full range of analytes measurable in DBS, or any systematic approach published for characterizing the strengths and weaknesses associated with adoption of DBS analyses. CONTENT A scoping review of reviews methodology was used for characterizing the state of the science in DBS. We identified 2018 analytes measured in DBS and found every common analytic method applied to traditional liquid samples had been applied to DBS samples. Analytes covered a broad range of biomarkers that included genes, transcripts, proteins, and metabolites. Strengths of DBS enable its application in most clinical and laboratory settings, and the removal of phlebotomy and the need for refrigeration have expanded biosampling to hard-to-reach and vulnerable populations. Weaknesses may limit adoption in the near term because DBS is a nontraditional sample often requiring conversion of measurements to plasma or serum values. Opportunities presented by novel methodologies may obviate many of the current limitations, but threats around the ethical use of residual samples must be considered by potential adopters. SUMMARY DBS provide a wide range of potential applications that extend beyond the reach of traditional samples. Current limitations are serious but not intractable. Technological advancements will likely continue to minimize constraints around DBS adoption.

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Biodiversity of Secondary Metabolites Compounds Isolated from Phylum Actinobacteria and Its Therapeutic Applications

Molecules ◽

10.3390/molecules26154504 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4504

Author(s):

Muhanna Al-shaibani ◽

Radin Maya Saphira Radin Mohamed ◽

Nik Sidik ◽

Hesham Enshasy ◽

Adel Al-Gheethi ◽

...

Keyword(s):

Secondary Metabolites ◽

Bioactive Compounds ◽

Extreme Environments ◽

Software Tool ◽

Gene Clusters ◽

Well Being ◽

Bioactive Substances ◽

Diverse Range ◽

Wide Range ◽

Potential Applications

The current review aims to summarise the biodiversity and biosynthesis of novel secondary metabolites compounds, of the phylum Actinobacteria and the diverse range of secondary metabolites produced that vary depending on its ecological environments they inhabit. Actinobacteria creates a wide range of bioactive substances that can be of great value to public health and the pharmaceutical industry. The literature analysis process for this review was conducted using the VOSviewer software tool to visualise the bibliometric networks of the most relevant databases from the Scopus database in the period between 2010 and 22 March 2021. Screening and exploring the available literature relating to the extreme environments and ecosystems that Actinobacteria inhabit aims to identify new strains of this major microorganism class, producing unique novel bioactive compounds. The knowledge gained from these studies is intended to encourage scientists in the natural product discovery field to identify and characterise novel strains containing various bioactive gene clusters with potential clinical applications. It is evident that Actinobacteria adapted to survive in extreme environments represent an important source of a wide range of bioactive compounds. Actinobacteria have a large number of secondary metabolite biosynthetic gene clusters. They can synthesise thousands of subordinate metabolites with different biological actions such as anti-bacterial, anti-parasitic, anti-fungal, anti-virus, anti-cancer and growth-promoting compounds. These are highly significant economically due to their potential applications in the food, nutrition and health industries and thus support our communities’ well-being.

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A Structurally Variable Hinged Tetrahedron Framework from DNA Origami

Journal of Nucleic Acids ◽

10.4061/2011/360954 ◽

2011 ◽

Vol 2011 ◽

pp. 1-9 ◽

Cited By ~ 18

Author(s):

David M. Smith ◽

Verena Schüller ◽

Carsten Forthmann ◽

Robert Schreiber ◽

Philip Tinnefeld ◽

...

Keyword(s):

Self Assembly ◽

Gel Electrophoresis ◽

Imaging Techniques ◽

Building Blocks ◽

Dna Origami ◽

Microscopy Technique ◽

Wire Frame ◽

Wide Range ◽

Potential Applications ◽

Linker Molecules

Nanometer-sized polyhedral wire-frame objects hold a wide range of potential applications both as structural scaffolds as well as a basis for synthetic nanocontainers. The utilization of DNA as basic building blocks for such structures allows the exploitation of bottom-up self-assembly in order to achieve molecular programmability through the pairing of complementary bases. In this work, we report on a hollow but rigid tetrahedron framework of 75 nm strut length constructed with the DNA origami method. Flexible hinges at each of their four joints provide a means for structural variability of the object. Through the opening of gaps along the struts, four variants can be created as confirmed by both gel electrophoresis and direct imaging techniques. The intrinsic site addressability provided by this technique allows the unique targeted attachment of dye and/or linker molecules at any point on the structure's surface, which we prove through the superresolution fluorescence microscopy technique DNA PAINT.

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Mathematics in the spirit of Joe Keller

European Journal of Applied Mathematics ◽

10.1017/s0956792517000171 ◽

2017 ◽

Vol 28 (5) ◽

pp. 708-715

Author(s):

J. R. OCKENDON ◽

B. D. SLEEMAN

Keyword(s):

20Th Century ◽

Natural Phenomena ◽

Wide Range ◽

The World ◽

Mathematical Techniques

Over the two days 2–3 March 2017, about 80 mathematicians and friends gathered in Cambridge to celebrate the life and work of Joseph Bishop Keller (1923–2016), one of the pre-eminent applied mathematicians of the 20th century. Joe, as he was known throughout the world, made pioneering contributions to a wide range of natural phenomena and developed fundamental mathematical techniques with which to understand them. Twenty-four talks were presented at the meeting, given by mathematicians who have either worked with Joe or have been influenced by his work. Rather than summarise each presentation, we have collated all the contributions under the headings of waves, fluids, solids, chemistry and biology, and finally some history.

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Effects of H2 Addition to CNG Blends on Cycle-to-Cycle and Cylinder-to-Cylinder Combustion Variation in an SI Engine

ASME 2012 Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/ices2012-81187 ◽

2012 ◽

Cited By ~ 1

Author(s):

Mirko Baratta ◽

Stefano d’Ambrosio ◽

Daniela Misul ◽

Ezio Spessa

Keyword(s):

Diagnostic Tool ◽

Combustion Process ◽

Experimental Tests ◽

Test Point ◽

Pollutant Emissions ◽

Engine Operation ◽

Pressure Transducers ◽

Rate Analysis ◽

Spark Plug ◽

Wide Range

An experimental investigation and a burning-rate analysis have been performed on a production 1.4 liter CNG (compressed natural gas) engine fueled with methane-hydrogen blends. The engine features a pent-roof combustion chamber, four valves per cylinder and a centrally located spark plug. The experimental tests have been carried out in order to quantify the cycle-to-cycle and the cylinder-to-cylinder combustion variation. Therefore, the engine has been equipped with four dedicated piezoelectric pressure transducers placed on each cylinder and located by the spark plug. At each test point, in-cylinder pressure, fuel consumption, induced air mass flow rate, pressure and temperature at different locations on the engine intake and exhaust systems as well as ‘engine-out’ pollutant emissions have been measured. The signals correlated to the engine operation have been acquired by means of a National Instruments PXI-DAQ system and a home developed software. The acquired data have then been processed through a combustion diagnostic tool resulting from the integration of an original multizone thermodynamic model with a CAD procedure for the evaluation of the burned-gas front geometry. The diagnostic tool allows the burning velocities to be computed. The tests have been performed over a wide range of engine speeds, loads and relative air-fuel ratios (up to the lean operation). For stoichiometric operation, the addition of hydrogen to CNG has produced a bsfc reduction ranging between 2 to 7% and a bsTHC decrease up to the 40%. These benefits have appeared to be even higher for lean mixtures. Moreover, hydrogen has shown to significantly enhance the combustion process, thus leading to a sensibly lower cycle-to-cycle variability. As a matter of fact, hydrogen addition has generally resulted into extended operation up to RAFR = 1.8. Still, a discrepancy in the abovementioned conclusions was observed depending on the engine cylinder considered.

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