Single-molecule observation of nucleotide induced conformational changes in basal SecA-ATP hydrolysis

11 pages ; illustrationsSecA is the critical adenosine triphosphatase that drives preprotein transport through the translocon, SecYEG, in Escherichia coli. This process is thought to be regulated by conformational changes of specific domains of SecA, but real-time, real-space measurement of these changes is lacking. We use single-molecule atomic force microscopy (AFM) to visualize nucleotide-dependent conformations and conformational dynamics of SecA. Distinct topographical populations were observed in the presence of specific nucleotides. AFM investigations during basal adenosine triphosphate (ATP) hydrolysis revealed rapid, reversible transitions between a compact and an extended state at the ~100-ms time scale. A SecA mutant lacking the precursor-binding domain (PBD) aided interpretation. Further, the biochemical activity of SecA prepared for AFM was confirmed by tracking inorganic phosphate release. We conclude that ATP-driven dynamics are largely due to PBD motion but that other segments of SecA contribute to this motion during the transition state of the ATP hydrolysis cycle.Funding: This work was supported by the National Science Foundation (CAREER award number 1054832 to G.M.K.) and a Burroughs Wellcome Fund Career Award at the Scientific Interface (to G.M.K.)Nagaraju Chada1*, Kanokporn Chattrakun1, Brendan P. Marsh1†, Chunfeng Mao2, Priya Bariya2, Gavin M. King1,2‡: 1Department of Physics and Astronomy, University of Missouri–Columbia, Columbia, MO 65211, USA. 2Department of Biochemistry, University of Missouri–Columbia, Columbia, MO 65211, USA. *Present address: Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA. †Present address: Department of Applied Physics, Stanford University, Stanford, CA 94305 USA. ‡Corresponding author.Nagaraju Chada (1*), Kanokporn Chattrakun (1), Brendan P. Marsh (1†), Chunfeng Mao (2), Priya Bariya (2), Gavin M. King (1,2‡) -- References: 1) Department of Physics and Astronomy, University of Missouri–Columbia, Columbia,MO 65211, USA ; 2) Department of Biochemistry, University of Missouri–Columbia, Columbia, MO 65211, USA ; *) Present address: Department of Biology, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA ; †) Present address: Department of Applied Physics, Stanford University, Stanford, CA 94305 USA ; ‡) Corresponding author

Development of Communication and Speech Skills of Students in the Process of Education

The article aims to study and diagnose school students with disabilities' levels of communication and speech skills development. Communication technologies in the process of forming communicative competence will contribute to the successful implementation of correctional work, if necessary, an individual or adapted educational program for students with disabilities. During the conduction of the study, the authors used the following types of methods: analysis, synthesis, modelling, observation, survey - statistical method analysis of the data allowed to differentiate levels of communication and speech skills development. The authors revealed the most effective forms and methods of work at the literature levels. The scientific-methodical and practical aspects of the application of communication technologies for the development of school students with disabilities' speech activities were generalized. In modern education, it has been substantiated that communication technologies are used as a means of communication skills formation and as a means of activation of the students' cognitive work. Based on the theoretical analysis of the investigated problem and the experimental work results, the authors have formulated the generalizing positions. It was concluded that the solution to the investigation of the school students with disabilities' speech activities development problem is possible at smart scientific and methodological use of communication technologies

Internet of Things for Sustainable Human Health

The sustainable health IoT has the strong potential to bring tremendous improvements in human health and well-being through sensing, and monitoring of health impacts across the whole spectrum of climate change. The sustainable health IoT enables development of a systems approach in the area of human health and ecosystem. It allows integration of broader health sub-areas in a bigger archetype for improving sustainability in health in the realm of social, economic, and environmental sectors. This integration provides a powerful health IoT framework for sustainable health and community goals in the wake of changing climate. In this chapter, a detailed description of climate-related health impacts on human health is provided. The sensing, communications, and monitoring technologies are discussed. The impact of key environmental and human health factors on the development of new IoT technologies also analyzed

A Scale Independent Selection Process for 3D Object Recognition in Cluttered Scenes

During the last years a wide range of algorithms and devices have been made available to easily acquire range images. The increasing abundance of depth data boosts the need for reliable and unsupervised analysis techniques, spanning from part registration to automated segmentation. In this context, we focus on the recognition of known objects in cluttered and incomplete 3D scans. Locating and fitting a model to a scene are very important tasks in many scenarios such as industrial inspection, scene understanding, medical imaging and even gaming. For this reason, these problems have been addressed extensively in the literature. Several of the proposed methods adopt local descriptor-based approaches, while a number of hurdles still hinder the use of global techniques. In this paper we offer a different perspective on the topic: We adopt an evolutionary selection algorithm that seeks global agreement among surface points, while operating at a local level. The approach effectively extends the scope of local descriptors by actively selecting correspondences that satisfy global consistency constraints, allowing us to attack a more challenging scenario where model and scene have different, unknown scales. This leads to a novel and very effective pipeline for 3D object recognition, which is validated with an extensive set of experiment

Wearable sweat sensors

Sweat potentially contains a wealth of physiologically relevant information, but has traditionally been an underutilized resource for non-invasive health monitoring. Recent advances in wearable sweat sensors have overcome many of the historic drawbacks of sweat sensing and such sensors now offer methods of gleaning molecular-level insight into the dynamics of our bodies. Here we review key developments in sweat sensing technology. We highlight the potential value of sweat-based wearable sensors, examine state-of-The-Art devices and the requirements of the underlying components, and consider ways to tackle data integrity issues within these systems. We also discuss challenges and opportunities for wearable sweat sensors in the development of personalized healthcare

Wearable sweat sensors

Sweat potentially contains a wealth of physiologically relevant information, but has traditionally been an underutilized resource for non-invasive health monitoring. Recent advances in wearable sweat sensors have overcome many of the historic drawbacks of sweat sensing and such sensors now offer methods of gleaning molecular-level insight into the dynamics of our bodies. Here we review key developments in sweat sensing technology. We highlight the potential value of sweat-based wearable sensors, examine state-of-The-Art devices and the requirements of the underlying components, and consider ways to tackle data integrity issues within these systems. We also discuss challenges and opportunities for wearable sweat sensors in the development of personalized healthcare

Demarcation of Potential Groundwater Recharge Zones Through REMOTE Sensing, GIS, and MCDA: A Case Study of the Aji River Basin in Saurashtra, Gujarat, India

Groundwater is an important and valuable natural resource. Due to extensive agricultural practices and industrial developments, groundwater resources have recently been overexploited and depleted. Therefore, there is a need to adopt sustainable water resource management practices to augment groundwater recharge. This study uses advanced geospatial technologies to identify potential groundwater recharge zones in the Aji River Basin in the Saurashtra region of Gujarat, India. The primary objective was to enhance potential groundwater recharge zones in the Aji River basin region. Therefore, various parameters affecting groundwater availability, including lineament, geology, soil, density, slope, rainfall, land use/land cover, geomorphology, and drainage density, were considered for delineating potential groundwater recharge zones. The integrated approach, using remote sensing (RS), geographical information system (GIS), and multi-criteria decision analysis (MCDA), was employed to achieve this. The influence factor was determined through Satty`s analytic hierarchy process (AHP) method. The sub-parameters were ranked according to the AHP scale, and a weighted overlay analysis tool in ArcGIS software was utilized to map the potential groundwater recharge zones in the basin. The concluding map was categorized into five distinct zones based on potential groundwater recharge zones: ‘Excellent’ (50.50 km2, 2.36 %), ‘Good’ (1376.78 km2, 64.56 %), ‘Moderate’ (599.14 km2, 28.09 %), ‘Poor’ (90.67 km2, 4.25 %), and ‘Very Poor’ (15.32 km2,0.718 %). The SCS-Curve number method was employed to assess the potential for rainfall-induced runoff. The Aji River basin exhibited a weighted mean rainfall and runoff of 622.68 mm and 241.07 mm, respectively. The estimated weighted runoff for the Aji River basin was 514.07 million cubic meters (MCM), with a 75 % exceedance probability, resulting in a runoff of 152.97 MCM. This study concludes that integrating remote sensing, GIS, and MCDA techniques effectively identifies and delineates potential groundwater recharge zones, which is crucial for sustainable water resource management

Trace-Level, Multi-Gas Detection for Food Quality Assessment Based on Decorated Silicon Transistor Arrays.

Multiplexed gas detection at room temperature is critical for practical applications, such as for tracking the complex chemical environments associated with food decomposition and spoilage. An integrated array of multiple silicon-based, chemical-sensitive field effect transistors (CSFETs) is presented to realize selective, sensitive, and simultaneous measurement of gases typically associated with food spoilage. CSFETs decorated with sensing materials based on ruthenium, silver, and silicon oxide are used to obtain stable room-temperature responses to ammonia (NH3 ), hydrogen sulfide (H2 S), and humidity, respectively. For example, one multi-CSFET sensor signal changes from its baseline by 13.34 in response to 1 ppm of NH3 , 724.45 under 1 ppm H2 S, and 23.46 under 80% relative humidity, with sensitive detection down to 10 ppb of NH3 and H2 S. To demonstrate this sensor for practical applications, the CSFET sensor array is combined with a custom-printed circuit board into a compact, fully integrated, and portable system to conduct real-time monitoring of gases generated by decomposing food. By using existing silicon-based manufacturing methodologies, this room-temperature gas sensing array can be fabricated reproducibly and at low cost, making it an attractive platform for ambient gas measurement needed in food safety applications