L-header Testing, Evaluation and Design Methodology

Cold-formed steel L-shaped headers have gained popularity over the past few years due to their simplicity and cost effectiveness. While cold-formed steel conventional headers are widely used and can be designed for most applications, often it is necessary to reduce cost by using less material and labor hours. The L-shaped header provides both, a fast and economical solution to safely transfer applied loads to other structural elements in a building. As the name suggests, the main components of an L-shaped header is a piece of cold-formed steel formed into a shape resembling the letter L. An L-header assembly consists of a cold-formed steel angle with one short leg lapping over the top track and one long leg extending down the side of the wall above openings. The current design equations in the AlSI Specification do not provide a reasonable design values for L-header assemblies. Testing of the assemblies was necessary to develop an easy to use design equations that can be used by designers. A total of 71 gravity tests and 38 uplift tests of L-header assemblies having variable sizes and thicknesses and spans were conducted at the NAHB Research Center. Results of the tests as well as a proposed design procedure is presented here

Distance learning: opportunities and challenges in quarantine.

The urgent introduction of distance education into the learning process due to the COVID-19 pandemic has become a spontaneous experiment, requiring urgent decisions, effective mechanisms to implement into the educational process and analysis of ongoing educational process. The possibilities of modern digital technologies made it possible to quickly set up the information component of education and to controle student’s knowledge. A detailed analysis of the communication between the faculty members of the department among themselves and analysis of the features of teaching and self-education of students in the field of medical radiology and oncology based on answers and comments with using Google classroom, Socrative, Messenger Telegram, etc. was made. Issues of communicative interaction between faculty members and students, psychological aspects of distance communication, language of instruction, logistics of distance education and methodological problems are described in details. It has been suggested that distance education may be equally effective for theoretical subjects in full-time study form, but when studying clinical disciplines, the priority should be given to traditional methods of teaching, involving student's bedside training. Taking into account technical possibilities and high risk of development of extreme and emergency situations, it is suggested to introduce permanent readiness for distance education, to create all – Ukrainian distance imitation service of patients’ follow-up. The importance of using the state language in training as the basis for mastering the professional Ukrainian and English language as the basis for mastering international medical experience is indicated

Cysteine redox proteomics of the hemoglobin-depleted cytosolic fraction of stored red blood cells.

PURPOSE: Erythrocyte concentrates (ECs) represent the most transfused labile blood products. They are stored at 4°C in additive solutions for up to 56 days. Protein oxidation is a marker of oxidative stress and cysteine residues, whose oxidations are required for physiological cell functions, are highly prone to such modification. EXPERIMENTAL DESIGN: Five ECs from independent donations were followed. Soluble protein extracts were prepared at days 6, 27, and 41, and cysteines were alkylated, reduced, and labeled with infrared dyes. Samples were mixed two by two (day 6 as reference) and analyzed by 2D-DIGE. Detection of labeled cysteines allows quantitative comparison of oxidative status. Spots of interest were analyzed by proteomics. RESULTS: Thirty-two spots containing 43 proteins were classified as increasing, decreasing, or exhibiting a peak of expression during storage. Proteins having catalytic and antioxidant activities were particularly affected during storage, for example, peroxiredoxin-1 and DJ-1 were reversibly oxidized and catalase was irreversibly oxidized. These proteins could be used to evaluate different storage strategies to maintain proper protein function during the overall storage period. CONCLUSIONS AND CLINICAL RELEVANCE: This redox-DIGE approach brings new quantitative data on oxidized proteins in stored red blood cells. As previously reported on carbonylation, the oxidative damages differently affect protein functions

Internet-based remote sensing and manipulation in micro environment

Recent developments in the Internet have significantly increased the human capability to reach and obtain information from remote locations. In parallel, the advent of micro sensors and actuators makes it possible for humans to sense and act in a microenvironment. Combined, the Internet and ME will produce a new technology for humans to sense and act in remote microenvironments, allowing the potential development of micro teleoperation and micro automation technologies. These new technologies have potential impact on several fields, including remote micro-automation and biomedical engineering. In this paper, we will present our ongoing development of polyvinylidence fluoride (PVDF) sensors that can be used force-reflective control of micromechanical devices over the Internet. Internet based teleoperation between Hong Kong and Michigan State was demonstrated using an event-based control scheme, which ensured stability and synchronization. Control was enhanced by multimedia feedback, which included, in add ition to the traditional video, force feedback. The force fed back augmented the limited information supplied by visual feedback. We believe this project will eventually make a great impact to the globalization of MEMS foundries because it will allow global users to micro-assemble and micro-manipulate surface micromachined devices from their laboratories, and hence, reduce the time from design to production significantly.Link_to_subscribed_fulltex

Challenge of forecasting demand of medical resources and supplies during a pandemic: A comparative evaluation of three surge calculators for COVID-19

Ever since the World Health Organization (WHO) declared the new coronavirus disease 2019 (COVID-19) as a pandemic, there has been a public health debate concerning medical resources and supplies including hospital beds, intensive care units (ICU), ventilators and protective personal equipment (PPE). Forecasting COVID-19 dissemination has played a key role in informing healthcare professionals and governments on how to manage overburdened healthcare systems. However, forecasting during the pandemic remained challenging and sometimes highly controversial. Here, we highlight this challenge by performing a comparative evaluation for the estimations obtained from three COVID-19 surge calculators under different social distancing approaches, taking Lebanon as a case study. Despite discrepancies in estimations, the three surge calculators used herein agree that there will be a relative shortage in the capacity of medical resources and a significant surge in PPE demand if the social distancing policy is removed. Our results underscore the importance of implementing containment interventions including social distancing in alleviating the demand for medical care during the COVID-19 pandemic in the absence of any medication or vaccine. The paper also highlights the value of employing several models in surge planning

A bone reaming system using micro sensors for Internet force-feedback control

The development of a medical surgical tool packaged with micro sensors for transmission of Supermedia information over the Internet is described in this paper. We define Supermedia as a set of communication media, which encompasses acoustic, force, visual, audio, temperature, tactile, and chemical (e.g., taste an smell) information, and which can be physically experienced by a communicator. In this project, we specifically develop Supermedia capability for a bone-reaming system that is used for intramedullary fixation procedure of fractured bone treatments. Thus far, transmission of temperature, force, and pressure information from MEMS sensors over the Internet has been demonstrated. Force-reflective control over the Internet using force information from a micro tip has also been shown. We have also packaged a MEMS pressure sensor inside a bone reaming guide-rod and proved that pressure variations inside a long cavity that simulated the environment inside a bone can be monitored, even with the guide-rod rotating up to 600rpm. This paper describes our experimental methods and gives the experimental results for these accomplishments.Link_to_subscribed_fulltex

Modeling and control of Internet based cooperative teleoperation

Robotic operations carried out via the Internet face several challenges and difficulties. These range from human-computer interfacing and human-robot interaction to overcoming random time delay and task synchronization. These limitations are intensified when multi-operators at multi-sites are collaboratively teleoperating multi-robots to achieve a certain task. In this paper, a new modeling and control method for Internet-based cooperative teleoperation is developed. Combining Petri Net model and event-based planning and control theory, the new method provides an efficient way to model the concurrence and complexity of the Internet-based cooperative teleoperation. It also provides an efficient analysis tool to study the stability, transparency and synchronization of the system. Furthermore, the new modeling and control method enables us to design an Internet-based cooperative telerobotic system that is reliable, safe and intelligent. This new method has been experimentally implemented in a three site tes t bed consisting of robotic laboratories in the USA, Hong Kong and Japan. The experimental results have verified the theoretical development and further demonstrated the advantages of the new modeling and control method.Link_to_subscribed_fulltex

Electrochemical fabrication of TiO2 -Au nanocomposites

Nanocomposites comprised of electrosynthesized/annealed TiO2 on indium tin oxide substrates, using the electrogeneration of base method, followed by electrodeposited gold clusters are presented, and their photoelectrochemical response is examined. The TiO2 films are nodular with a rough morphology. Gold nanoparticles were electrodeposited onto the electrogenerated TiO2 with galvanostatic pulses. A step photoresponse analysis was employed to characterize the photoelectrochemical behavior of three different forms of the TiO2-Au composite: (i) TiO2 decorated with Au nanoparticles, TiO2/Au, (ii) TiO2 with embedded Au nanoparticles in a sandwichlike fashion, TiO2/Au/TiO 2, and (iii) TiO2 with embedded and decorated Au nanoparticles, TiO2/Au/TiO2/Au. The TiO2/Au composite resulted in the highest photocurrent response under UV irradiation and in a broadening of the photocurrent response to the visible region, although with successive testing a decrease in the photocurrent response was observed. The photoresponse of the buried Au nanoparticles, TiO2/Au/TiO 2, was slightly lower compared to Au decorating the TiO2 electrosynthesized surface, TiO2/Au, but significantly higher than pristine electrosynthesized TiO2. © 2009 The Electrochemical Society