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The use of low energy, ion induced nuclear reactions for proton radiotherapy applications
Medical radiotherapy has traditionally relied upon the use of external photon beams and internally implanted radioisotopes as the chief means of irradiating tumors. However, advances in accelerator technology and the exploitation of novel means of producing radiation may provide useful alternatives to some current modes of medical radiation delivery with reduced total dose to surrounding healthy tissue, reduced expense, or increased treatment accessibility. This paper will briefly overview currently established modes of radiation therapy, techniques still considered experimental but in clinical use, innovative concepts under study that may enable new forms of treatment or enhance existing ones. The potential role of low energy, ion-induced nuclear reactions in radiotherapy applications is examined specifically for the 650 keV d({sup 3}He,p){sup 4}He nuclear reaction. This examination will describe the basic physics associated with this reaction`s production of 17.4 MeV protons and the processes used to fabricate the necessary materials used in the technique. Calculations of the delivered radiation dose, heat generation, and required exposure times are presented. Experimental data are also presented validating the dose calculations. The design of small, lower cost ion accelerators, as embodied in `nested`-tandem and radio frequency quadrupole accelerators is examined, as is the potential use of high-output {sup 3}He and deuterium ion sources. Finally, potential clinical applications are discussed in terms of the advantages and disadvantages of this technique with respect to current radiotherapy methods and equipment
Fall prevention intervention technologies: A conceptual framework and survey of the state of the art
In recent years, an ever increasing range of technology-based applications have been developed with the goal of assisting in the delivery of more effective and efficient fall prevention interventions. Whilst there have been a number of studies that have surveyed technologies for a particular sub-domain of fall prevention, there is no existing research which surveys the full spectrum of falls prevention interventions and characterises the range of technologies that have augmented this landscape. This study presents a conceptual framework and survey of the state of the art of technology-based fall prevention systems which is derived from a systematic template analysis of studies presented in contemporary research literature. The framework proposes four broad categories of fall prevention intervention system: Pre-fall prevention; Post-fall prevention; Fall injury prevention; Cross-fall prevention. Other categories include, Application type, Technology deployment platform, Information sources, Deployment environment, User interface type, and Collaborative function. After presenting the conceptual framework, a detailed survey of the state of the art is presented as a function of the proposed framework. A number of research challenges emerge as a result of surveying the research literature, which include a need for: new systems that focus on overcoming extrinsic falls risk factors; systems that support the environmental risk assessment process; systems that enable patients and practitioners to develop more collaborative relationships and engage in shared decision making during falls risk assessment and prevention activities. In response to these challenges, recommendations and future research directions are proposed to overcome each respective challenge.The Royal Society, grant Ref: RG13082
The use of low energy, ion induced nuclear reactions for proton radiotherapy applications
Lung surfactant in subacute pulmonary disease
Pulmonary surfactant is a surface active material composed of both lipids and proteins that is produced by alveolar type II pneumocytes. Abnormalities of surfactant in the immature lung or in the acutely inflamed mature lung are well described. However, in a variety of subacute diseases of the mature lung, abnormalities of lung surfactant may also be of importance. These diseases include chronic obstructive pulmonary disease, asthma, cystic fibrosis, interstitial lung disease, pneumonia, and alveolar proteinosis. Understanding of the mechanisms that disturb the lung surfactant system may lead to novel rational therapies for these diseases
Optimization of Model Parameters for Describing the Amide I Spectrum of a Large Set of Proteins
Environmental influences on reproductive health: the importance of chemical exposures
Chemical exposures during pregnancy can have a profound and life-long impact on human health. Due to the omnipresence of chemicals in our daily life, there is continuous contact with chemicals in food, water, air and consumer products. Consequently, human biomonitoring studies show that pregnant women around the globe are exposed to a variety of chemicals. In this review, we provide a summary of current data on maternal and fetal exposure as well as health consequences from these exposures. We review several chemical classes including polychlorinated biphenyls (PCBs), perfluoroalkyl substances (PFAS), polybrominated diphenyl ethers (PBDEs), phenols, phthalates, pesticides, and metals. Additionally, we discuss environmental disparities and vulnerable populations, and future research directions. We conclude by providing some recommendations for prevention of chemical exposure and its adverse reproductive health consequences
SBML Level 3: an extensible format for the exchange and reuse of biological models
Systems biology has experienced dramatic growth in the number, size, and complexity of computational models. To reproduce simulation results and reuse models, researchers must exchange unambiguous model descriptions. We review the latest edition of the Systems Biology Markup Language (SBML), a format designed for this purpose. A community of modelers and software authors developed SBML Level 3 over the past decade. Its modular form consists of a core suited to representing reaction-based models and packages that extend the core with features suited to other model types including constraint-based models, reaction-diffusion models, logical network models, and rule-based models. The format leverages two decades of SBML and a rich software ecosystem that transformed how systems biologists build and interact with models. More recently, the rise of multiscale models of whole cells and organs, and new data sources such as single-cell measurements and live imaging, has precipitated new ways of integrating data with models. We provide our perspectives on the challenges presented by these developments and how SBML Level 3 provides the foundation needed to support this evolution
Gothic Revival Architecture Before Horace Walpole's Strawberry Hill
The Gothic Revival is generally considered to have begun in eighteenth-century Britain with the construction of Horace Walpoleâs villa, Strawberry Hill, Twickenham, in the late 1740s. As this chapter demonstrates, however, Strawberry Hill is in no way the first building, domestic or otherwise, to have recreated, even superficially, some aspect of the form and ornamental style of medieval architecture. Earlier architects who, albeit often combining it with Classicism, worked in the Gothic style include Sir Christopher Wren, Nicholas Hawksmoor, William Kent and Batty Langley, aspects of whose works are explored here. While not an exhaustive survey of pre-1750 Gothic Revival design, the examples considered in this chapter reveal how seventeenth- and eighteenth-century Gothic emerged and evolved over the course of different architectsâ careers, and how, by the time that Walpole came to create his own Gothic âcastleâ, there was already in existence in Britain a sustained Gothic Revivalist tradition
Tachyarrhythmias, bradyarrhythmias and acute coronary syndromes
The incidence of bradyarrhythmias in patients with acute coronary syndrome (ACS) is 0.3% to 18%. It is caused by sinus node dysfunction (SND), high-degree atrioventricular (AV) block, or bundle branch blocks. SND presents as sinus bradycardia or sinus arrest. First-degree AV block occurs in 4% to 13% of patients with ACS and is caused by rhythm disturbances in the atrium, AV node, bundle of His, or the Tawara system. First- or second-degree AV block is seen very frequently within 24 h of the beginning of ACS; these arrhythmias are frequently transient and usually disappear after 72 h. Third-degree AV blocks are also frequently transient in patients with infero-posterior myocardial infarction (MI) and permanent in anterior MI patients. Left anterior fascicular block occurs in 5% of ACS; left posterior fascicular block is observed less frequently (incidence <0.5%). Complete bundle branch block is present in 10% to 15% of ACS patients; right bundle branch block is more common (2/3) than left bundle branch block (1/3). In patients with bradyarrhythmia, intravenous (IV) atropine (1-3 mg) is helpful in 70% to 80% of ACS patients and will lead to an increased heart rate. The need for pacemaker stimulation (PS) is different in patients with inferior MI (IMI) and anterior MI (AMI). Whereas bradyarrhythmias are frequently transient in patients with IMI and therefore do not need permanent PS, there is usually a need for permanent PS in patients with AMI. In these patients bradyarrhythmias are mainly caused by septal necrosis. In patients with ACS and ventricular arrhythmias (VTA) amiodarone is the drug of choice; this drug is highly effective even in patients with defibrillation-resistant out-of-hospital cardiac arrest. There is general agreement that defibrillation and advanced life support is essential and is the treatment of choice for patients with ventricular flutter/fibrillation. If defibrillation is not available in patients with cardiac arrest due to VTA, cardiopulmonary resuscitation is mandatory
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