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As we celebrate the 50th year of the American Association of Physicists in Medicine (AAPM), what better time to look back at our development as well as to look forward to the opportunities that lie ahead. Here the authors will review some of the achievements of the Education Council and show how the activities are helping to shape the future educational goals and opportunities of the AAPM and the medical physics profession. Much of the work of the Education Council is carried out by the various committees and subcommittees that make up the Council or have a liaison relationship with the Council. [ABSTRACT FROM AUTHOR]

Josep Rizo is a Professor of Biophysics, Biochemistry and Pharmacology at the University of Texas Southwestern Medical Center, where he is Virginia Lazenby O'Hara Chair in Biochemistry. He is particularly interested in the study of the mechanisms of neurotransmitter release and intracellular membrane fusion using structural biology, a variety of biophysical techniques and reconstitution approaches. Jose has been a part of the FEBS Open Bio Editorial Board since 2021. In this interview, he shares his insights into developments in the field of neurotransmitter release, describes his move from Spain to the United States, and discusses how sometimes you need to use both logic and scientific hunches. [ABSTRACT FROM AUTHOR]

This memorial issue is a collection of papers that showcase the diverse research interests of the late Professor King‐Chuen Lin (1953 – 2022) in the fields of physical chemistry, analytical chemistry, biophysics, and material chemistry. These papers have been contributed by Prof. Lin's friends, colleagues, and former group members. The global chemistry community deeply mourns the loss of Prof. Lin, and through this special issue, the invited contributors aim to honor his memory. [ABSTRACT FROM AUTHOR]

The article presents the editorial policy of the journal "Medical Physics."

The article discusses issues associated with the emergence of neuroscience-related information and issues associated with diminishing dominance of electrophysiology. Topics discussed include requirement for a modern interpretation of classic electrophysiology literature, application of the Nernst equation to describe the potential that results distribution of ions across semi-permeable cell membranes and issues associated with the invention of the voltage clamp.

Online submission and review of manuscripts is now required. Please follow the instructions for authors given below. When your manuscript has been prepared in accordance with these instructions, please access the following web site: . You must select Functional Ecology when you log on to the online submission site. [ABSTRACT FROM AUTHOR]

EMBO Press provides a platform for The EMBO Journal to publish papers that are more discoverable, accessible and optimized for sharing and promoting important research findings. [ABSTRACT FROM AUTHOR]

In Chinese philosophy, yin and yang ("dark‐bright," "negative‐positive") describe how seemingly opposite or contrary forces may actually be complementary, interconnected and interdependent. This paper provides this perspective on photodynamic and photothermal therapies, with a focus on the treatment of solid tumors. The relative strengths and weaknesses of each modality, both current and emerging, are considered with respect to the underlying biophysics, the required technologies, the biological effects, their translation into clinical practice and the realized or potential clinical outcomes. For each specific clinical application, one or the other modality may be clearly preferred, or both are effectively equivalent in terms of the various scientific/technological/practical/clinical trade‐offs involved. Alternatively, a combination may the best approach. Such combined approaches may be facilitated by the use of multifunctional nanoparticles. It is important to understand the many factors that go into the selection of the optimal approach and the objective of this paper is to provide guidance on this. [ABSTRACT FROM AUTHOR]

The 57th meeting and conference of the International Society for the Systems Sciences focused on the meta-theme of Curating the Conditions for a Thrivable Planet. The event was conceived as a living learning lab for collective intelligence that aimed to provide its participants with a set of total immersion environments in which to explore our role as systems scientists, and beyond that, as members of a globalizing species at this time in history. As such, the conference provided individual and collective opportunities to foster that basic feeling of being connected, to explore what it means to be appreciative systems (as Sir Geoffrey Vickers would have it) to manifest new levels of community and fundamentally, to evolve the narrative of our role as authors of the conscious evolution of our species. This paper presents the stage-setting remarks presented at the opening of the 57th annual meeting and conference of the ISSS, inviting members and conference participants to address the principal theme of this conference that took place in Vietnam: the search for systemic leverage points for emerging a global eco-civilization. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: Live observation of biological phenomena in the context of living organisms can provide important insights in the mechanisms of these phenomena. However, the spatially complex and dynamic physiology of multicellular organisms can be a challenging environment to make observations with fluorescence microscopy. Due to the illumination of out‐of‐focus planes, confocal and particularly widefield fluorescence microscopy suffer from low signal‐to‐background ratio (SBR), photo toxicity and bleaching of fluorescent probes. In light‐sheet microscopy (LSM), solely the focal plane of the detection objective is illuminated, minimising out‐of‐focus fluorescence and photobleaching, thereby enhancing SBR, allowing for low laser intensities and longer acquisition periods. Here we present a straightforward light‐sheet microscope with a 1.0‐NA detection objective and a fast sample‐positioning stage that allows for four degrees of freedom. By imaging the sensory cilia and nervous system of living young adult C. elegans, we demonstrate that the instrument is well suited for relatively fast, volumetric imaging of larger (hundreds of micrometres cubed) living samples. These experiments demonstrate that such an instrument provides a valuable addition to commonly used widefield and confocal fluorescence microscopes. Lay description: In fluorescence microscopy, sharp images can only be obtained when the light obtained from the section of the image that is in focus is not overwhelmed by light emerging from elsewhere. In this paper, we present a light‐sheet fluorescence microscope, based on the OpenSPIM initiative, with a magnification of 90× and a sensitive sample positioning stage that allows for fast controlled linear movement and rotation. In a light‐sheet microscope (LSM), the sample is illuminated from the side, compared to the direction of detection, limiting illumination only to the part of the sample that is imaged in the focal plane (general resources: Wikipedia or MicroscopyU). This does not only limit background noise, but also reduces damage to the sample due to phototoxicity. This makes a LSM particularly suitable for imaging living samples at high resolution, in three dimensions, over long periods of time. Our instrument was specifically designed for imaging adult C. elegans nematodes. We show here how the instrument compares to a standard epifluorescence microscope, imaging neuronal structures in the animals. The instrument proved well suited for fast volumetric imaging of larger cellular structures such as C. elegans neuronal cell bodies. Our experiments show that the instrument provides a valuable addition to widefield and confocal fluorescence microscopes commonly used to image adult C. elegans. [ABSTRACT FROM AUTHOR]

Although physics is a pre-requisite for dental students prior to matriculation it is not tested on the Dental Admissions Test (DAT). The concepts of physics are found throughout the dental profession, and by testing it on the DAT dental students will be better equipped to relate physics to their field and help advance it. The purpose of this paper is to make the argument for why it should be tested, as well as eliminating some of the superfluous topics on the DAT (ecology, environmental sciences, and plant physiology). This paperwill focus on a few of concepts already taught in dentistry, and explore how physics principles apply to several of them. We want to emphasize the importance of physics and how testing even the most basic concepts will help prepare students to "think outside the box". Classical physics, specifically Newtonian Mechanics, has several applications in nearly all areas of dentistry: restorative, orthodontics, prosthodontics, and surgery. The testing of basic formulas studied in the pre-requisite physics classeswill help ease the transition from college to dental school. Modern physics, namely Quantum Mechanics, also plays a significant role in current dental diagnostics and therapeutics. Additionally, with the development of the Integrated National Board Dental Examination (INBDE) as a replacement for the old NBDE part 1 and 2, there are topics tested that specifically focus on physics: Foundational Knowledge Areas 2 and 3. Thus, it is critical that the student dentist be familiar with these concepts. It is important to note that scientific changes occurring in the health sciences almost mandates students be familiar with concepts rooted in physics. It is then proposed that physics be incorporated into the exam, either with the natural sciences or within the quantitative reasoning section, in addition to eliminating topics not relevant to the dental field. [ABSTRACT FROM AUTHOR]

This paper aims to discuss the literature pertaining to early pressure‐shear induced tissue damage detection, with emphasis on sub‐epidermal moisture measurement (SEM). The current method for pressure detection is visual skin assessment (VSA); however, this method is fraught with challenges. Advances in early detection of pressure ulcers are reported in the literature and mainly involve measuring inflammation markers on weight‐bearing anatomical areas in order to capture the first signs of tissue damage. One novel technique currently in use is SEM measurement. This biophysical marker is the product of plasma that leaks as a response to local inflammation arising due to pressure‐shear induced damage over bony prominences. The early detection of tissue damage is beneficial in two different ways. First, it enables early intervention when the damage is still microscopic and reversible and, therefore, has the potential to prevent further aggravation of healthy surrounding tissue. This arises by avoiding the causation of the problem and stopping the knock‐on effect of inflammation, especially when the rapid pressure ulceration pathway of deformation is in place. Second, when the slow ischaemic‐reperfusion related mechanism is undergoing, cell death can be avoided when the problem is identified before the cell reaches the "death threshold," completely averting a pressure ulcer. [ABSTRACT FROM AUTHOR]

Clinicians rely on occlusal contact detection products to identify high contacts and to equilibrate occlusions. Concerns about these products have stimulated numerous investigations into marking reproducibility, accuracy and interpretation, but none have looked at their effects on the occlusion itself. The aim of this study was to assess whether these products alter the occlusion that they purport to measure by determining whether there are differences in the forces and moments experienced by occluding teeth with and without their presence. A matched pair of IPN Portrait 33° molar denture teeth was placed into occlusion with the mandibular tooth supported by a load sensor and the maxillary tooth mounted onto a vertically sliding assembly with a total weight of 15·1N. The three-dimensional force and moment components on the mandibular tooth were measured when the teeth were in direct crown-crown contact (control) and with the products in place. All six products, (Accufilm I, Accufilm II, Hanel Articulating Silk, Rudischhauser Thick and Thin, and T-scan) showed significant ( P < 0·05) differences in forces and moments from control. [ABSTRACT FROM AUTHOR]

The Lapindo mudflow is one of the most controversial disasters in Indonesian history. Despite its unique biophysical features, most consider the mudflow a social disaster as scientific conflicts about its main trigger have evolved into legal disputes over accountability and rights. This paper examines this 'trigger debate', the stakes of scientific contention and the broader social and natural dynamics that shape the terms of this debate. A Latourian impulse drives this analysis, which aims to improve both understandings of-and responses to-complex disasters. This paper also notes that the stakes of representation extend to constructions of its stakeholders, especially to victims. As socionatural disasters become an increasingly common feature of the contemporary world, from mud volcanoes to extreme weather events caused by global warming, it is more important than ever to understand the dynamics of representing disasters and stakeholders. [ABSTRACT FROM AUTHOR]

Aim. The aim of this in vivo study was to evaluate the accuracy and reliability of electronic apex locater and radiographic determination of root canal length in primary teeth. Methodology. A total of 32 human primary molar teeth (96 roots) were selected. After endodontic access preparation, root canals were irrigated with physiological saline solution. The access cavities were dried with cotton pellets and, the roots were dried with paper points before performing the electronic measurement. The root canal length measurements were first taken with an apex locater (EndoMaster), and then, a size # 15 K-file was inserted into the root canal, and radiography was taken to determine the working length measurements. The measurement data were recorded and compared by one-way ANOVA and Kruskal-Wallis tests. P < 0.05 was accepted for the significance. Results. The mean values for radiography were 13.23 ± 1.92 mm and for EndoMaster were 13.08 ± 1.77 mm. The accuracy of EndoMaster was 80.2% in correct measurements ±1m m (P < 0.001). Conclusion. The electronic apex locators could be useful in determining working length and thereby decreasing the need for radiographs and exposure to ionizing radiation in pediatric dental patients. [ABSTRACT FROM AUTHOR]

Functional protein delivery has created new opportunities for studying intracellular processes and discovering new therapeutics. To that end, researchers have pursued intracellular protein delivery by using an increasing number of methods. This focus review will highlight polymeric carriers that non‐covalently bind and deliver protein cargo in vitro. The correlation between polymer–protein binding and delivery as well as the correlation between complex–membrane binding and delivery is reviewed. Finally, binding and its relation to the intracellular function of the protein post‐delivery is considered. The purpose of this review is to evaluate the role that binding interactions play in the non‐covalent protein‐delivery landscape. Presently, the literature does not adequately resolve how binding throughout the process ultimately affects delivery. The field does contain preliminary insights that are expected to impact future delivery applications when developed further. Signed, sealed, delivered: Non‐covalent intracellular protein delivery relies on associative and dissociative processes, but they are not always quantified and correlated with delivery outcomes. This paper covers what is known about how binding processes impact intracellular protein delivery. Three main topics are discussed: polymer–protein complex formation and binding affinity, complex–membrane binding, and intracellular complex dissociation. [ABSTRACT FROM AUTHOR]

Small arteries and their component cellular and non-cellular elements are continually subjected to, and interact with, mechanical forces. Such interactions are key in both short- and long-term adaptation of the structure and function of the microcirculation to its local environment and metabolic requirements. Following this brief introduction is a series of papers presented as a symposium (Small Artery Mechanobiology: Roles of Cellular and Non-Cellular Elements) at the World Congress for Microcirculation, Kyoto 2015., (© 2016 John Wiley & Sons Ltd.)

Due to the presence of the complex life cycles involving a benthic adult and a pelagic larval phase, the study of benthic community dynamics cannot ignore investigations of the processes occurring in the water column. Current investigations focus mainly on larval dispersal from an evolutionary and a biogeographic perspective, taking into account also population connectivity, conservation planning and coastal management. In the present paper we underline the need to improve knowledge of the main traits of marine invertebrate life cycles, highlighting the limits and challenges of current approaches. Firstly, we summarized the changing approaches within community studies, following the paradigm shifts found in recent marine ecological research, from supply-side ecology to connectivity, and involving the concepts of open and closed populations. Secondly, we analysed the main larval traits influencing dispersal, paying particular attention to pelagic larval duration in light of the few available data for connectivity studies. The difficulty in estimating many of the main traits of larval ecology make numerical simulation fundamental for a better understanding of the relationship between propagule dispersal and seawater dynamics, both being highly variable. We conclude that some essential biological information is still lacking for the proper integration of the modeling approaches. Thus it is necessary to further investigate the life-cycle traits and physiological and ecological characteristics of each species, an approach known as autecology or natural history. All too frequently modern ecologists ignore such reductionist approaches, although they are essential for a full understanding of processes, such as connectivity and metapopulation dynamics. [ABSTRACT FROM AUTHOR]

The creation of accurate three-dimensional reconstructions of biological surfaces is often challenging due to several inherent limitations of current imaging technologies. These include the inability to image living material, requirements for extensive specimen preparation and/or long image acquisition times, and the inability to image at length scales that are relevant for the study of interfacial phenomena that occur between the organism and its environment., In this paper, we demonstrate the use of a new imaging approach that combines the benefits of optical and contact profilometry to image organismal surfaces quickly and without the need for any kind of specimen preparation, thus permitting three-dimensional visualization in situ., As a proof of concept, we demonstrate the utility of this approach by imaging the surfaces of a wide range of live and preserved fish and other species, imaging wet, mucus-covered surfaces, and presenting quantitative metrics of surface roughness in a variety of natural and engineered materials., Given the numerous wet, sticky, and slimy surfaces that abound in nature and the importance of the interface between species and their environments for the study of numerous biophysical phenomena, we believe this approach holds considerable promise for providing new insights into surface structural complexity in biological systems. [ABSTRACT FROM AUTHOR]

High‐resolution spatio‐temporal monitoring of the cell membrane lipid order provides visual insights into the complex and sophisticated systems that control cellular physiological functions. Solvatochromic fluorescent probes are highly promising noninvasive visualization tools for identifying the ordering of the microenvironment of plasma membrane microdomains. However, conventional probes, although capable of structural analysis, lack the necessary long‐term photostability required for live imaging at the cellular level. Here, an ultra‐high‐light‐resistant solvatochromic fluorescence probe, 2‐N,N‐diethylamino‐7‐(4‐methoxycarbonylphenyl)‐9,9‐dimethylfluorene (FπCM) is reported, which enables live lipid order imaging of cell division. This probe and its derivatives exhibit sufficient fluorescence wavelengths, brightness, polarity responsiveness, low phototoxicity, and remarkable photostability under physiological conditions compared to conventional solvatochromic probes. Therefore, these probes have the potential to overcome the limitations of fluorescence microscopy, particularly those associated with photobleaching. FπCM probes can serve as valuable tools for elucidating mechanisms of cellular processes at the bio‐membrane level. [ABSTRACT FROM AUTHOR]

In this study, a novel, high content technique using a cylindrical acoustic transducer, stroboscopic fast imaging, and homodyne detection to recover the mechanical properties (dynamic shear modulus) of living adherent cells at low ultrasonic frequencies is presented. By analyzing the micro‐oscillations of cells, whole populations are simultaneously mechanotyped with sub‐cellular resolution. The technique can be combined with standard fluorescence imaging allowing to further cross‐correlate biological and mechanical information. The potential of the technique is demonstrated by mechanotyping co‐cultures of different cell types with significantly different mechanical properties. [ABSTRACT FROM AUTHOR]

Molecular biology techniques play a very important role in understanding the biological activity. Students who major in biology should know not only how to perform experiments, but also the reasons for performing them. Having the concept of conducting research by integrating various techniques is especially important. This paper introduces a research project-based and self-determined teaching system of molecular biology techniques for undergraduates. Its aim is to create an environment mimicking real research programs and to help students build up confidence in their research skills. The students are allowed to explore a set of commonly used molecular biology techniques to solve some fundamental problems about genes on their own. They find a gene of interest, write a mini-proposal, and give an oral presentation. This course provides students a foundation before entering the research laboratory and allows them to adapt easily to real research programs. [ABSTRACT FROM AUTHOR]

Managers of Ramsar-listed wetlands throughout the world are committed to management that will promote the conservation and wise use of their wetland habitats. Part of the management process is a description of ‘ecological character’ as a benchmark against which a ‘change in ecological character’ can be assessed. Detecting unacceptable change is a difficult judgement, which depends upon an understanding of wetland ecosystem components, processes and services. This paper explores the development of conceptual models as a framework for describing the biophysical elements of ecological character of a wetland in a way that can be readily used for assessing changes. Ecosystem services are partially addressed but need further work to be more fully incorporated. We suggest development of models to identify components and key processes as well as drivers in the ecosystem. These models provide a description of a unique set of identifiers and a baseline against which unacceptable changes in biophysical character can be assessed. For an ecological character description to be useful for adaptive management, we suggest following the process, developed in a case study at Thomsons Lake, Western Australia, which: (i) provides a landscape context and identifies relevant spatial scales using a hierarchy of maps and aerial photographs; (ii) develops a conceptual ecological model with an accompanying synthesis of relevant biophysical data; and (iii) uses these as the basis for recognizing a unique set of wetland identifiers. The latter, together with critical processes, are the core biophysical elements of an ecological character description. Construction of a driver/stressor model facilitates the recognition of external drivers which create ecological stressors and lead to adverse ecological effects and loss of ecosystem services and benefits. It then follows that unacceptable changes in ecological character are those that result in a loss of identifiers, disrupt critical processes and reduce services or benefits. [ABSTRACT FROM AUTHOR]

Highlights several conferences related to biomechanics. 40th annual general meeting of the British Society for Strain Measurement; 12th International Conference on Experimental Mechanics in Bari, Italy; 13th International Conference on Experimental Mechanics in Greece.

Microclimatic variables are necessary for a wide range of pure and applied problems in environmental science. In ecology, microclimatic conditions are prerequisites for modelling the heat and water budgets of organisms, from which climatic constraints on behaviour, life histories, distribution and abundance can be inferred. Despite the critical importance of microclimates, there is no general-purpose, accessible microclimate model available for use in ecological studies. Here we introduce and document the microclimate model of the biophysical modelling package NicheMapR, an R package that includes a suite of programs for mechanistic modelling of heat and mass exchange between organisms and their environments. The NicheMapR microclimate model is based on a Fortran program originally developed by Porter, Mitchell, Beckman and McCullough for predicting hourly above- and below-ground conditions from meteorological, terrain, vegetation and soil data. The model includes routines for computing solar radiation, including effects of shading, slope, aspect and horizon angles (hillshade), and can include variable substrate properties with depth. Here we configure the program to be called from R as part of the NicheMapR package, and describe the model in detail including new functionality for modelling soil water balance and snow, optional input of hourly or daily weather input data, and an R implementation of the Global Aerosol Data Set for obtaining local estimates of aerosol profiles as input to the model. We include scripts for core operation of the model, for building a global, monthly long-term average dataset with all necessary environmental inputs, for computing physical properties of air, and for running the model with the global climate database. Example applications are provided in the paper and in the associated vignettes, including customisation the model to run with user-supplied weather inputs. [ABSTRACT FROM AUTHOR]

Predictive light transport models based on first-principles simulation approaches have been proposed for complex organic materials. The driving force behind these efforts has been the high-fidelity reproduction of material appearance attributes without one having to rely on the manipulation of ad hoc parameters. These models, however, are usually considered excessively time consuming for rendering and visualization applications requiring interactive rates. In this paper, we propose a strategy to address this open problem with respect to one of the most challenging of these organic materials, namely the human iris. More specifically, starting with the configuration of a predictive iridal light transport model on a parallel-computing platform, we analyze the sensitivity of iridal appearance attributes to key model running parameters in order to achieve an optimal balance between fidelity and performance. We believe that the proposed strategy represents a step toward the real-time and predictive synthesis of high-fidelity iridal images for rendering and visualization applications, and it can be extended to other organic materials. [ABSTRACT FROM AUTHOR]

On 23 and September 24, 2021, the international conference entitled "The latest achievements in biochemistry, biophysics and biotechnology - 50 years of history of the Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Kraków, Poland" was held in Kraków, Poland (https://jubileuszwbbib.confer.uj.edu.pl/en%5fGB/). The conference was organised to mark the 50th anniversary of the foundation of the Institute of Molecular Biology, which was then transformed into the Faculty of Biochemistry, Biophysics and Biotechnology (https://wbbib.uj.edu.pl/en GB/start-en). The latest achievements in biochemistry, biophysics and biotechnology - 50 years of history of the Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University in Kraków, Poland. [Extracted from the article]

The author discusses the importance of biophysical processes of plant growth and development, citing an article by M. R. Nelson and colleagues. It discusses the format of the study group that consists experimental biologists. The authors of the study predict the possibility the anther's two-dimensional geometry as dehydration function. The paper suggests that epidermal dehydration is enough to make the conversion from a closed to an open anther.

An ultrasonication approach was adopted for Azadirachta indica driven bioconversion of silver salt into silver nanoparticle (AgNPs). These nanoparticles were coated over plasma functionalized cotton by using a pad dry cure technique. For pre‐coat surface functionalization, the cotton fabric was exposed to an open air single dielectric barrier discharge (DBD). The emission spectrum revealed that DBD consisted of NO, O3, O, O2+ , O+, OH−, N2 and N2+ species. The plasma treatment produced negative radicals on the surface and improved the adhesion of fabric for nanoparticles. The crystallographic analysis revealed cubical structure of nanoparticles with average size of 25 nm. The fabric got fully covered with AgNPs after five pad‐dry cycles. Nanoparticles together with neem extract promoted the antimicrobial activity of the coated fabric. The inhibition zone of the silver coated fabric against E.Coli strains increased from 6 mm to 14 mm. The conductivity of fabric after 3, 5 and 7 cycles remained 2.56× 10−2, 2.63× 10−2 and 2.67× 10−2 Siemens/cm, respectively. The coated fabric showed UV protection factor in the range of 210–269. The transmittance of UV−A radiations and UV−B radiations from the uncoated fabric was 19.27 % and 7.84 %, respectively, which reduced to 0.76 % and 0.24 % after 7 pad dry cycles. [ABSTRACT FROM AUTHOR]

Bulges are essential structural elements in nucleic acids. The detection and targeting of bulged DNA sequences are highly important. Small molecules capable of targeting DNA bulges have attracted considerable attention because they cannot only be used as reagents for bulge recognition, but also as potential therapeutic drugs. Herein, the interactions of DNA duplexes, containing bulges of various sizes and base compositions, with a series of FeII triplex‐forming metallohelices are reported. The results obtained, with the aid of molecular biophysics methods, show that the investigated metallohelices prefer to bind to bulged DNA, rather than double‐stranded DNA, and that their binding affinities towards bulges differ among individual metallohelices. Moreover, their binding affinities towards bulges strongly depend on the bulge size and the base composition of the bulge loop. The investigated metallohelices can enter eukaryotic cells and accumulate in the cell nucleus, allowing them to interact with nucleic acids. Hence, it is reasonable to suggest that the interaction of metallohelices with nucleic acid bulges might contribute to the mechanism of their biological activity. [ABSTRACT FROM AUTHOR]

Background: Plantar foot skin exhibits unique biophysical properties that are distinct from skin on other areas of the body. This paper characterises, using non-invasive methods, the biophysical properties of foot skin in healthy and pathological states including xerosis, heel fissures, calluses and corns. Methods: Ninety three people participated. Skin hydration, elasticity, collagen and elastin fibre organisation and surface texture was measured from plantar calluses, corns, fissured heel skin and xerotic heel skin. Previously published criteria were applied to classify the severity of each skin lesion and differences in the biophysical properties compared between each classification. Results: Calluses, corns, xerotic heel skin and heel fissures had significantly lower levels of hydration; less elasticity and greater surface texture than unaffected skin sites (p < 0.01). Some evidence was found for a positive correlation between hydration and elasticity data (r = 0.65) at hyperkeratotic sites. Significant differences in skin properties (with the exception of texture) were noted between different classifications of skin lesion. Conclusions: This study provides benchmark data for healthy and different severities of pathological foot skin. These data have applications ranging from monitoring the quality of foot skin, to measuring the efficacy of therapeutic interventions. [ABSTRACT FROM AUTHOR]

This paper presents a time-varying, multi-layered biophysically-based model of the optical properties of human skin, suitable for simulating appearance changes due to aging. We have identified the key aspects that cause such changes, both in terms of the structure of skin and its chromophore concentrations, and rely on the extensive medical and optical tissue literature for accurate data. Our model can be expressed in terms of biophysical parameters, optical parameters commonly used in graphics and rendering (such as spectral absorption and scattering coefficients), or more intuitively with higher-level parameters such as age, gender, skin care or skin type. It can be used with any rendering algorithm that uses diffusion profiles, and it allows to automatically simulate different types of skin at different stages of aging, avoiding the need for artistic input or costly capture processes. While the presented skin model is inspired on tissue optics studies, we also provided a simplified version valid for non-diagnostic applications. [ABSTRACT FROM AUTHOR]

SUMMARY Mass transport processes are known to play an important role in many fields of biomechanics such as respiratory, cardiovascular, and biofilm mechanics. In this paper, we present a novel computational model considering the effect of local solid deformation and fluid flow on mass transport. As the transport processes are assumed to influence neither structure deformation nor fluid flow, a sequential one-way coupling of a fluid-structure interaction (FSI) and a multi-field scalar transport model is realized. In each time step, first the non-linear monolithic FSI problem is solved to determine current local deformations and velocities. Using this information, the mass transport equations can then be formulated on the deformed fluid and solid domains. At the interface, concentrations are related depending on the interfacial permeability. First numerical examples demonstrate that the proposed approach is suitable for simulating convective and diffusive scalar transport on coupled, deformable fluid and solid domains. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper outlines the contributions of social science to the study of interactions between urbanization patterns and processes and the carbon cycle, and identifies gaps in knowledge and priority areas for future social scientific research contributions. While previously studied as a unidimensional process, we conceptualize urbanization as a multidimensional, social and biophysical process driven by continuous changes across space and time in various subsystems including biophysical, built environment, and socio-institutional (e.g., economic, political, demographic, behavioral, and sociological). We review research trends and findings focused on the socio-institutional subsystem of the urbanization process, and particularly the dynamics, relationships, and predictions relevant to energy use and greenhouse gas emissions. Our findings suggest that a multidimensional perspective of urbanization facilitates a wider spectrum of research relevant to carbon cycle dynamics, even within the socio-institutional subsystem. However, there is little consensus around the details and mechanisms underlying the relationship between urban socio-institutional subsystems and the carbon cycle. We argue that progress in understanding the relationship between urbanization and the carbon cycle may be achieved if social scientists work collaboratively with each other as well as with scientists from other disciplines. From this review, we identify research priorities where collaborative social scientific efforts are necessary in conjunction with other disciplinary approaches to generate a more complete understanding of urbanization as a process and its relationship to the carbon cycle. [ABSTRACT FROM AUTHOR]

The death of Edward Carmeliet has robbed us of one of the founders of modern cardiac electrophysiology. Carmeliet made important contributions to our understanding of pacemaker mechanisms and the properties of the acetylcholine-sensitive K SP + sp channel (Callewaert I et al i . 1984; Carmeliet & Mubagwa, 1986). K SP + sp currents are a prime target to modulate action potential duration, and the delayed rectifier current a strong candidate (Carmeliet, 1992b). Calcium signalling and the action potential Edward Carmeliet made major contributions to our understanding of calcium signalling in the heart. [Extracted from the article]

Thermal adaptation of enzymes is essential for both living organism development in extreme conditions and efficient biocatalytic applications. However, the molecular mechanisms leading to a shift in catalytic activity optimum temperatures remain unclear, and there is increasing experimental evidence that thermal adaptation involves complex changes in both structural and reactive properties. Here, a combination of enhanced protein conformational sampling with an explicit chemical reaction description was applied to mesophilic and thermophilic homologues of the dihydrofolate reductase enzyme, and a quantitative description of the stability and catalytic activity shifts between homologues was obtained. The key role played by temperature‐induced shifts in protein conformational distributions is revealed. In contrast with pictures focusing on protein flexibility and dynamics, it is shown that while the homologues' reaction free energies are similar, the striking discrepancy between their activation energies is caused by their different conformational changes with temperature. An analytic model is proposed that combines catalytic activity and structural stability, and which quantitatively predicts the shift in homologue optimum temperatures. It is shown that this general model provides a molecular explanation of changes in optimum temperatures for several other enzymes. [ABSTRACT FROM AUTHOR]

SUMMARY A proper and efficient representation of possibly complex and large molecular surfaces is an important task in bioinformatics and biophysics. Molecular surfaces indeed are used for different aims, in particular, for computation, as visual support tools for biologists, in electrostatics problems involving implicit solvents (e.g. while solving the Poisson-Boltzmann equation) or for molecular dynamics simulations. This is the reason why, in literature, a multitude of algorithms that differ on the basis of the adopted representation and the approach/technology used were proposed. In this paper we present a CUDA-based software component able to produce high-resolution molecular surfaces based on the Van der Waals, solvent accessible, Richards-Connolly and blobby definitions. The component was designed to be used in heterogeneous visualization pipelines; therefore, the representation of the molecular surfaces suits both the direct visualization and the efficient storing for following processing steps. Experimental results show speedup figures between 39.3 and 88.4 considering molecules of different sizes and surface resolutions, resulting in meshes of up to 258.6 million triangles. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

One of the key advantages of a low-flying unmanned aircraft system (UAS) is its ability to acquire digital images at an ultrahigh spatial resolution of a few centimeters. Remote sensing of quantitative biochemical and biophysical characteristics of small-sized spatially fragmented vegetation canopies requires, however, not only high spatial, but also high spectral (i.e., hyperspectral) resolution. In this paper, we describe the design, development, airborne operations, calibration, processing, and interpretation of image data collected with a new hyperspectral unmanned aircraft system (HyperUAS). HyperUAS is a remotely controlled multirotor prototype carrying onboard a lightweight pushbroom spectroradiometer coupled with a dual frequency GPS and an inertial movement unit. The prototype was built to remotely acquire imaging spectroscopy data of 324 spectral bands (162 bands in a spectrally binned mode) with bandwidths between 4 and 5 nm at an ultrahigh spatial resolution of 2-5 cm. Three field airborne experiments, conducted over agricultural crops and over natural ecosystems of Antarctic mosses, proved operability of the system in standard field conditions, but also in a remote and harsh, low-temperature environment of East Antarctica. Experimental results demonstrate that HyperUAS is capable of delivering georeferenced maps of quantitative biochemical and biophysical variables of vegetation and of actual vegetation health state at an unprecedented spatial resolution of 5 cm. [ABSTRACT FROM AUTHOR]

Gravity has shaped the evolution of life since its origin. However, experiments in the absence of this overriding force, necessary to precisely analyse its role, e.g. for growth, development, and orientation of plants and single cells, only became possible with the advent of spaceflight. Consequently, this research has been supported especially by space agencies around the world for decades, mainly for two reasons: first, to enable fundamental research on gravity perception and transduction during growth and development of plants; and second, to successfully grow plants under microgravity conditions with the goal of establishing a bioregenerative life support system providing oxygen and food for astronauts in long-term exploratory missions. For the second time, the International Space Life Sciences Working Group ( ISLSWG), comprised of space agencies with substantial life sciences programmes in the world, organised a workshop on plant biology research in space. The present contribution summarises the outcome of this workshop. In the first part, an analysis is undertaken, if and how the recommendations of the first workshop held in Bad Honnef, Germany, in 1996 have been implemented. A chapter summarising major scientific breakthroughs obtained in the last 15 years from plant research in space concludes this first part. In the second part, recommendations for future research in plant biology in space are put together that have been elaborated in the various discussion sessions during the workshop, as well as provided in written statements from the session chairs. The present paper clearly shows that plant biology in space has contributed significantly to progress in plant gravity perception, transduction and responses - processes also relevant for general plant biology, including agricultural aspects. In addition, the interplay between light and gravity effects has increasingly received attention. It also became evident that plants will play a major role as components of bioregenerative life support and energy systems that are necessary to complement physico-chemical systems in upcoming long-term exploratory missions. In order to achieve major progress in the future, however, standardised experimental conditions and more advanced analytical tools, such as state-of-the-art onboard analysis, are required. [ABSTRACT FROM AUTHOR]

People who are food and nutrition insecure largely reside in Asia and Sub-Saharan Africa and for many, fish represents a rich source of protein, micronutrients and essential fatty acids. The contribution of fish to household food and nutrition security depends upon availability, access and cultural and personal preferences. Access is largely determined by location, seasonality and price but at the individual level it also depends upon a person's physiological and health status and how fish is prepared, cooked and shared among household members. The sustained and rapid expansion of aquaculture over the past 30 years has resulted in >40% of all fish now consumed being derived from farming. While aquaculture produce increasingly features in the diets of many Asians, it is much less apparent among those living in Sub-Saharan Africa. Here, per capita fish consumption has grown little and despite the apparently strong markets and adequate biophysical conditions, aquaculture has yet to develop. The contribution of aquaculture to food and nutrition security is not only just an issue of where aquaculture occurs but also of what is being produced and how and whether the produce is as accessible as that from capture fisheries. The range of fish species produced by an increasingly globalized aquaculture industry differs from that derived from capture fisheries. Farmed fishes are also different in terms of their nutrient content, a result of the species being grown and of rearing methods. Farmed fish price affects access by poor consumers while the size at which fish is harvested influences both access and use. This paper explores these issues with particular reference to Asia and Africa and the technical and policy innovations needed to ensure that fish farming is able to fulfil its potential to meet the global population's food and nutrition needs. [ABSTRACT FROM AUTHOR]

In attempts to determine the crystal structure of small molecule-protein complexes, a common frustration is the absence of ligand binding once the protein structure has been solved. While the first structure, even with no ligand bound (apo), can be a cause for celebration, the solution of dozens of apo structures can give an unwanted sense of déjà vu. Much time and material is wasted on unsuccessful experiments, which can have a serious impact on productivity and morale. There are many reasons for the lack of observed binding in crystals and this paper highlights some of these. Biophysical methods may be used to confirm and optimize solution conditions to increase the success rate of crystallizing protein-ligand complexes. As there are an overwhelming number of biophysical methods available, some of the factors that need to be considered when choosing the most appropriate technique for a given system are discussed. Finally, a few illustrative examples where biophysical methods have proven helpful in real systems are given.

Soil systems are characterized by the spatial and temporal distribution of organic and mineral particles, water and air within a soil profile. Investigations into the complex interactions between soil constituents have greatly benefited from the advent of non-invasive techniques for structural analysis. In this paper we present a review of the application of one such technique, X-ray computed tomography ( CT), for studies of undisturbed soil systems, focusing on research during the last 10 years in particular. The ability to undertake three-dimensional imaging has provided valuable insights regarding the quantitative assessment of soil features, in a way previously unachievable because of the opaque nature of soil. A dynamic approach to the evaluation of soil pore networks, hydro-physical characteristics and soil faunal behaviour has seen numerous scanning methodologies employed and a diverse range of image analysis protocols used. This has shed light on functional processes across multiple scales whilst also bringing its own challenges. In particular, much work has been carried out to link a soil's porous architecture with hydraulic function, although new technical improvements allowing the characterization of organic matter and the influence of soil biota on structural development are showing great promise. Here we summarize the development of X-ray CT in soil science, highlight the major issues relating to its use, outline some of the applications for overcoming these challenges and describe the potential of future technological advances for non-invasive soil characterization through integration with other complementary techniques. [ABSTRACT FROM AUTHOR]

Purpose: Breast density is considered a significant risk factor and an important biomarker influencing the later risk of breast cancer. Prior breast segmentation is required when quantifying breast density with MRI in order to calculate the total breast volume and exclude nonbreast surrounding tissues. This paper describes an automatic 3D breast volume segmentation approach. Methods: The method is based on 3D local edge detection using phase congruency and Poisson surface reconstruction to extract the total breast volume. The boundary localization framework is integrated to a subsequent shape atlas-based segmentation using a Laplacian framework. Results: The 3D segmentation achieves breast-air and breast-chest wall boundary localization errors with a median of 1.36 mm and 2.68 mm, respectively, and an average volume error of 153.8 cm3 when tested on 409 MRI datasets. Furthermore, the breast volume assessment technique will produce a 5.3% variability in the estimation of breast density in the tested population. Conclusions: The fully automated segmentation approach of the breast in MRI allows the computation of total breast volume, a step required for breast density assessment. The use of features invariant to image intensity and a shape atlas to reinforce shape consistency are attractive characteristics of the method. Error analysis demonstrates that 5.3% variability in the estimation of breast density incurred by the method is an acceptable trade-off. [ABSTRACT FROM AUTHOR]

Astronomers and physicists of diverse interest are teaming up to study enigmatic cosmic phenomena, such as the life cycle of black holes. A 'disruptive innovation' is about to emerge during the next decade: Advanced gravitational-wave observatories. The emergence of gravitational-wave physics as a viable observational channel is expected to improve our understanding of the Universe in unprecedented and plausibly unexpected ways, and to enhance the capabilities of the astrophysics community. Detecting cosmic counterparts to gravitational-wave events would revolutionize our understanding of violent astrophysical processes, such as the birth and death of black holes and neutron stars. Although the vanguard of joint observational work with electromagnetic observatories has already rewarded us with a glimpse of the power of gravitational-wave astronomy, the most interesting science is yet to come. Many sources of gravitational-waves are expected to be observable through a broad set of messengers, including γ-rays, X-rays, optical, radio, and neutrino emission. Multimessenger investigations may be crucial for the first detection of gravitational-waves, and could provide the broadest scientific impact afterwards. This paper outlines some exciting aspects of transient multimessenger astronomy with gravitational-waves and highlights open questions that might be resolvable by Advanced or third generation gravitational-wave detector networks. In addition, we will use examples from current research to illustrate that the toolkit of fundamental research can enrich other fields, and that synergistic science can expand horizons here on Earth. [ABSTRACT FROM AUTHOR]

Cutaneous burn wounds represent a significant public health problem with 500,000 patients per year in the USA seeking medical attention. Immediately after skin burn injury, the volume of the wound burn expands due to a cascade of chemical reactions, including lipid peroxidation chain reactions. Such expansion threatens life and is therefore highly clinically significant. Based on these chemical reactions, the present paper develops for the first time a three-dimensional mathematical model to quantify the propagation of tissue damage within 12 hours post initial burn. We use the model to investigate the effect of supplemental antioxidant vitamin E for intercepting propagation. We show, for example, that if tissue levels of vitamin E tocotrienol are increased, postburn, by five times then this would slow down the lipid peroxide propagation by at least 50%. We chose the alpha-tocotrienol form of vitamin E as it is a potent inhibitor of 12-lipoxygenase, which is known to propagate oxidative lipid damage. Our model is formulated in terms of differential equations, and sensitivity analysis is performed on the parameters to ensure the robustness of the results. [ABSTRACT FROM AUTHOR]

Koga K, Tsujimoto A, Ishii R, Iino M, Kotaku M, Takamizawa T, Tsubota K, Miyazaki M. Influence of oxygen inhibition on the surface free-energy and dentin bond strength of self-etch adhesives. Eur J Oral Sci 2011; 119: 395-400. © 2011 Eur J Oral Sci We compared the surface free-energies and dentin bond strengths of single-step self-etch adhesives with and without an oxygen-inhibited layer. The labial dentin surfaces of bovine mandibular incisors were wet ground with #600-grit silicon carbide paper. The adhesives were applied to the ground dentin, light-irradiated, and the oxygen-inhibited layer was either retained or removed with ethanol. The surface free-energies were determined by measuring the contact angles of three test liquids placed on the cured adhesives. The dentin bond strengths of specimens with and without the oxygen-inhibited layer were measured. For all surfaces, the value of the estimated surface tension component was relatively constant at 35.5-39.8 mJ m−2. The value of the , Lewis acid component increased slightly when the oxygen-inhibited layer was removed, whereas that of the , Lewis base component decreased significantly. The bond strengths of the self-etch adhesives were significantly lower in specimens without an oxygen-inhibited layer (13.2-13.6 MPa) than in those with an oxygen-inhibited layer (17.5-18.4 MPa). These results indicate that the presence of an oxygen-inhibited layer in single-step self-etch adhesives with advanced photoinitiators promotes higher dentin bond strength. [ABSTRACT FROM AUTHOR]