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Temporal lobe epilepsy (TLE) is one of the most common subtypes of focal epilepsy, with mesial temporal sclerosis (MTS) being a common radiological and histopathological finding. Accurate identification of MTS during presurgical evaluation confers an increased chance of good surgical outcome. Here we propose the use of glutamate-weighted chemical exchange saturation transfer (GluCEST) magnetic resonance imaging (MRI) at 7 Tesla for mapping hippocampal glutamate distribution in epilepsy, allowing to differentiate lesional from non-lesional mesial TLE. We demonstrate that a directional asymmetry index, which quantifies the relative difference between GluCEST contrast in hippocampi ipsilateral and contralateral to the seizure onset zone, can differentiate between sclerotic and non-sclerotic hippocampi, even in instances where traditional presurgical MRI assessments did not provide evidence of sclerosis. Overall, our results suggest that hippocampal glutamate mapping through GluCEST imaging is a valuable addition to the presurgical epilepsy evaluation toolbox.

Dropped frames can occur in line-scan cameras, which result in non-uniform spatial sampling of the scene. A dropped frame occurs when data from an image sensor is not successfully recorded. When mosaicking multiple line-scan images, such as in high-resolution imaging, this can cause misalignment. Much previous work to identify dropped frames in video prioritises fast computation over high accuracy, whereas in heritage imaging, high accuracy is often preferred over short computation time. Two approaches to identify the position of dropped frames are presented, both using the A* search algorithm to correct dropped frames. One method aligns overlapping sections of push-broom images and the other aligns the push-broom image to a lower resolution reference image. The two methods are compared across a range of test images, and the method aligning overlapping sections is shown to perform better than the method using a reference image under most circumstances. The overlap method was applied to hyperspectral images acquired of La Ghirlandata, an 1873 oil on canvas painting by D. G. Rossetti, enabling a high-resolution hyperspectral image mosaic to be produced. The resulting composite image is 10,875 \( \times \) 14,697 pixels each with 500 spectral bands from 400–2,500 nm. This corresponds to a spatial resolution of \( 80 \,\mathrm{\upmu }\mathrm{m} \) and a spectral resolution of 3–6 nm.

Echinoderms are characterized by a distinctive high-magnesium calcite endoskeleton as adults, but elements of this have been drastically reduced in some groups. Herein, we describe a new pentaradial echinoderm,Yorkicystis haefnerin. gen. n. sp., which provides, to our knowledge, the oldest evidence of secondary non-mineralization of the echinoderm skeleton. This material was collected from the Cambrian Kinzers Formation in York (Pennsylvania, USA) and is dated asca510 Ma. Detailed morphological observations demonstrate that the ambulacra (i.e. axial region) are composed of flooring and cover plates, but the rest of the body (i.e. extraxial region) is preserved as a dark film and lacks any evidence of skeletal plating. Moreover, X-ray fluorescence analysis reveals that the axial region is elevated in iron. Based on our morphological and chemical data and on taphonomic comparisons with other fossils from the Kinzers Formation, we infer that the axial region was originally calcified, while the extraxial region was non-mineralized. Phylogenetic analyses recoverYorkicystisas an edrioasteroid, indicating that this partial absence of skeleton resulted from a secondary reduction. We hypothesize that skeletal reduction resulted from lack of expression of the skeletogenic gene regulatory network in the extraxial body wall during development. Secondary reduction of the skeleton inYorkicystismight have allowed for greater flexibility of the body wall.

Mental health and general health care research has shown that practitioners can facilitate patient involvement in shared decision making (SDM) and that the approach can benefit patients who wish to take part in decisions around their care. Yet patient experiences of SDM within a psychotherapy context have been little researched. This study examined how clients experienced SDM in a collaborative-integrative psychotherapy. A grounded theory approach used interpersonal process recall interviewing and supplementary semi-structured interviews to investigate 14 clients' experiences of SDM in pluralistic psychotherapy for depression. Verbatim transcripts were coded into 819 meaning units across six categories containing 13 subcomponents that comprised a single, core category. The six categories were (a) experiencing decisions as shared, (b) psychotherapists supporting clients to become more active in the decision-making process, (c) both parties presenting and recognizing expert knowledge, (d) clients felt recognized as an individual and accommodated for by their psychotherapist, (e) clients felt comfortable engaging with the decision-making process, and (f) daunting for clients to be asked to take part in decision discussions. A core category emerged of "Psychotherapists encourage client participation and progressively support clients to provide information and contributions towards shared treatment decisions that could be led equally, or marginally more by one party." Such support was particularly useful when clients had difficulty contributing as part of decision discussions. Client preferences for SDM change across clients and across decisions, highlighting the importance of practitioners remaining flexible to individual clients when using the approach.

This document outlines aspects of innovation considered relevant for HS and proposes general actions for an Exploitation plan. Innovation is an essential component of the strategic objectives of E-RIHS. It encompasses novel research actions, offer of unique access services and provision of smart tools. Exploiting innovation, for the benefit of the E-RIHS ecosystem and the society, requires a number of actions along the innovation chain, including the presence of an efficient monitoring and evaluation system, appropriate knowledge and technology transfer channels, proper IPR protection and efficient communication with key stakeholders both in the public and the private sectors. An overall systematic approach to the above will ensure success and sustainability of ERIHS as an innovator and as a leader in the global HS landscape. This document is Deliverable 6.2, elaborated in the context of project IPERION HS, WP-06: Innovation and Exploitation, Task 6.4: Exploitation Plan. The analysis for the work presented herein was based on extensive interactions between the co-authors and builds upon a number of documents produced in the context of IPERION HS and E-RIHS PP (in particular Deliverable 9.4: Innovation Agenda).

Purpose: The purpose of this study is to characterise the magnitude and depth of dose build-up in pencil beam scanning proton therapy. Methods: We simulate the integrated depth-dose curve of realistic proton pencil beams in a water phantom using the the Geant4 Monte Carlo toolkit. We independently characterise the electronic and protonic components of dose build-up as a function of proton beam energy from 40 to 400 MeV, both with and without an air gap. Results: At clinical energies, electronic build-up over a distance of about 1mm leads to a dose reduction at depth of the basal layer (0.07 mm) by up to 6% compared to if no build-up effect were present. Protonic build-up reduces the dose to the basal layer by up to 16% and has effects at depths of up to 150 mm. Secondary particles with a mass number A > 1 do not contribute to dose build-up. An air gap of one metre has no significant effect on protonic build-up but reduces electronic build-up below 1%. Conclusions: Protonic and electronic dose build-up are relevant for accurate dosimetry in proton therapy although a realistic air gap reduces the electronic build-up to levels where it can be safely neglected. We recommend including electrons and secondary protons in Monte Carlo-based treatment planning systems down to a predicted range of 10-20 µm in order to accurately model the dose at depths of the basal layer, no matter the size of the air gap between nozzle and patient.

This workshop takes place online as part of theSustainable Heritage Bidecennial Conferenceand will introduce participants to the field of imaging applications in the study and management of heritage. The focus will be placed on developing skills for the use of photogrammetry in heritage - specifically through studying the process of creating a 3D model of a museum object from start to finish using basic photogrammetry equipment. Workshop participants will gain insight into the photogrammetric process, understand what is achievable with basic equipment, and become more aware of the requirements of 3D digitisation of museum objects and how these might differ from everyday objects.

The development and deployment of machine learning (ML) systems can be executed easily with modern tools, but the process is typically rushed and means-to-an-end. The lack of diligence can lead to technical debt, scope creep and misaligned objectives, model misuse and failures, and expensive consequences. Engineering systems, on the other hand, follow well-defined processes and testing standards to streamline development for high-quality, reliable results. The extreme is spacecraft systems, where mission critical measures and robustness are ingrained in the development process. Drawing on experience in both spacecraft engineering and ML (from research through product across domain areas), we have developed a proven systems engineering approach for machine learning development and deployment. Our Machine Learning Technology Readiness Levels (MLTRL) framework defines a principled process to ensure robust, reliable, and responsible systems while being streamlined for ML workflows, including key distinctions from traditional software engineering. Even more, MLTRL defines a lingua franca for people across teams and organizations to work collaboratively on artificial intelligence and machine learning technologies. Here we describe the framework and elucidate it with several real world use-cases of developing ML methods from basic research through productization and deployment, in areas such as medical diagnostics, consumer computer vision, satellite imagery, and particle physics.

The essential aim of Task 7.1 is to provide targeted training to develop suitably skilled individuals and to raise awareness amongst potential users of the benefits of using IPERION HS facilities. To this purpose, it has been decided to organize two Doctoral Summer Schools (HS-DSS) and two Training Camps (HS-TC) aimed at developing highly skilled professionals in the wider heritage research community, fostering cooperation between the academic community and heritage and research institutions. Several online meetings have been organized in order to discuss and decide about the curricula and dates of the training activities. Given the uncertainty linked with the ongoing pandemic, it was decided that the first HS-DSS will be delivered virtually in July 2021, whereas the first HS-TC will be implemented in person in 2022 when it is expected the current travel restrictions will not be active anymore. The first HS-DSS will mainly report on successful TNA and JRA achieved during the IPERION-CH project and will be addressed to a postgraduate, PhD and post-doc audience. As the HS-TC are intended to be more interactive and more appropriate for learners with a mixed educational and professional background, it was decided to organise them in person in 2022 and 2023 respectively. Both the HS-DSS and HS-TC will attract learners from a wide range of disciplines, so it is important to choose the subject materials and lecturers carefully.

The COVID-19 pandemic has disrupted the timing and substance of conservation research, management, and public engagement in protected areas around the world. This disruption is evident in US national parks, which play a key role in protecting natural and cultural resources and providing outdoor experiences for the public. Collectively, US national parks protect 34 million ha, host more than 300 million visits annually, and serve as one of the world's largest informal education organizations. The pandemic has altered park conditions and operations in a variety of ways. Shifts in operational conditions related to safety issues, reduced staffing, and decreased park revenues have forced managers to make difficult trade-offs among competing priorities. Long-term research and monitoring of the health of ecosystems and wildlife populations have been interrupted. Time-sensitive management practices, such as control of invasive plants and restoration of degraded habitat, have been delayed. And public engagement has largely shifted from in-person experiences to virtual engagement through social media and other online interactions. These changes pose challenges for accomplishing important science, management, and public engagement goals, but they also create opportunities for developing more flexible monitoring programs and inclusive methods of public engagement. The COVID-19 pandemic reinforces the need for strategic science, management planning, flexible operations, and online public engagement to help managers address rapid and unpredictable challenges.

Cutaneous T-cell Lymphoma (CTCL) is a rare form of non-Hodgkin lymphoma characterized by skin lesions, which can negatively impact the quality of life of both patients and their caregivers. The Decision Support Unit (DSU) at the National Institute for Health and Care Excellence (NICE) in the UK recently outlined a rationale for the inclusion of caregiver burden in economic evaluations. This study aimed to estimate utilities for health states associated with being a caregiver for an individual with CTCL at different stages of treatment.A targeted literature review and interviews with CTCL specialists informed the development of health state vignettes describing the experience caring for an individual with CTCL. The vignettes were evaluated in interviews with the UK general population using a visual analogue scale (VAS), the time trade-off (TTO) method and the EQ-5D-5L.Four vignettes were developed describing the caregiver experience for an individual with CTCL on i) second line treatment, ii) third line treatment, iii) end of life care, iv) a post-patient death. One hundred interviews were conducted to evaluate the health state vignettes. The pattern of results was similar across the evaluation methods: second line treatment (VAS: 39.2, TTO = 0.52, EQ-5D-5L: 0.56), third line treatment (VAS: 31.1, TTO = 0.39, EQ-5D-5L: 0.37), end of life care (VAS: 28.2, TTO = 0.37, EQ-5D-5L: 0.31) and post-patient death (VAS: 41.2, TTO = 0.63, EQ-5D-5L: 0.59).

Although multispectral imaging (MSI) of cultural heritage, such as manuscripts, documents and artwork, is becoming more popular, a variety of approaches are taken and methods are often inconsistently documented. Furthermore, no overview of the process of MSI capture and analysis with current technology has previously been published. This research was undertaken to determine current best practice in the deployment of MSI, highlighting areas that need further research, whilst providing recommendations regarding approach and documentation. An Action Research methodology was used to characterise the current pipeline, including: literature review; unstructured interviews and discussion of results with practitioners; and reflective practice whilst undertaking MSI analysis. The pipeline and recommendations from this research will improve project management by increasing clarity of published outcomes, the reusability of data, and encouraging a more open discussion of process and application within the MSI community. The importance of thorough documentation is emphasised, which will encourage sharing of best practice and results, improving community deployment of the technique. The findings encourage efficient use and reporting of MSI, aiding access to historical analysis. We hope this research will be useful to digitisation professionals, curators and conservators, allowing them to compare and contrast current practices.

Forensic scientists must be able to recover traces of any original explosive materials not consumed in the detonation, in a careful controlled manner to aid a crime reconstruction. In current sampling techniques, the collection efficiency of post-blast residue is highly variable and often dependent on the swabbing materials and solvent systems used. To address these method limitations, this study presents a gelatine-based sampling medium and assesses its capabilities for the collection of ammonium nitrate. Common surfaces were spotted with a known concentration of ammonium nitrate, the unset gel applied, allowed to set, and then peeled from the surface. The gel was dissolved, and solid phase extraction employed to isolate the target explosive compound and remove the constituents of the gel. The eluate was concentrated and subsequently analysed and quantified. Overall, the gel formulation was able to collect ammonium nitrate from all of the test surfaces, with recoveries ranging from 0.1% to 61.7%. This study presents a gelatine-based formulation that has the potential to become a valuable asset in the forensic tool kit for the collection of explosive traces. A key attribute of the gel is that it offers an alternative recovery tool to conventional swabbing and solvent extraction methods.

An abrupt societal shift toward increasingly impersonal, electronically mediated interaction contexts raises the question: how might such a change impact the process and outcomes of symbolic interaction? In this chapter we combine symbolic interactionist insights on role-taking with classical and contemporary scholarship on solidarity, interaction ritual chains, and bodily co-presence to advance a novel argument about how distance communication media may be undermining the microsocial foundations of human connectedness. We present results from a laboratory experiment in which we manipulated the communication medium between interaction partners and assessed vocal convergence—a non-consciously controlled, real-time indicator of group solidarity (i.e., interpersonal closeness). Results indicate that groups who interacted face-to-face experienced significantly greater solidarity than those who interacted in electronically mediated contexts. We discuss the implications of our findings and outline a research agenda that focuses on the promise of a neuro-interactionist approach, in particular, to provide a clearer understanding of the impact of distance media communication on symbolic interaction and social organization.

Biomedical Optics Express Editor-in-Chief Christoph K. Hitzenberger and Deputy Editor Adam Gibson share some final remarks as they prepare to end their editorial terms on 31 December 2021.

Terahertz (THz) imaging and optical coherence tomography (OCT) provide complementary information with similar length scales. In addition to OCT’s extensive use in ophthalmology, both methods have shown some promise for other medical applications and non-destructive testing. In this paper, we present an iterative algorithm that combines the information from OCT and THz imaging at two different measurement locations within an object to determine both the depth of the reflecting layers at the two locations and the unknown refractive index of the medium for both the OCT wavelengths and THz frequencies. We validate this algorithm using a silicone test object with embedded layers and show that the depths and refractive index values obtained from the algorithm agreed with the measured values to within 3.3%. We further demonstrate for the first time that OCT and THz images can be co-registered and aligned using unsupervised image registration. Hence we show that a combined OCT/THz system can provide unique information beyond the capability of the separate modalities alone, with possible applications in the medical, industrial and pharmaceutical sectors.

Multispectral (MSI) imaging of historical documents can recover lost features, such as text or drawings. This technique involves capturing multiple images of a document illuminated using different wavelengths of light. The images created must be registered in order to ensure optimal results are produced from any subsequent image processing techniques. However, the images may be misaligned due to the presence of optical elements such as filters, or because they were acquired at different times or because the images were captured from different copies of the documents . There is little prior work or information available about which image registration techniques are most appropriate. Image registration of multispectral images is challenging as the illumination changes for each image and the features visible in images captured at different wavelengths may not appear consistently throughout the image sequence. Here, we compare three image registration techniques: two based on similarity measures and a method based on phase correlation. These methods are characterized by applying them to realistic surrogate images and then assessed on three different sets of real multispectral images. Mutual information is recommended as a measure for affine image registration when working with multispectral images of documentary material as it was proven to be more robust than the other techniques tested.

Israel in Egypt is an oil on canvas painting by Sir Edward Poynter. In 1868 the painting was depicted in the Illustrated London News in which there are reports of changes made to the composition of the painting after its first exhibition. Visible and infrared imaging techniques have been used to determine whether additions to the initial composition can be identified from underdrawings. The painting measures 137 cm × 317.5 cm and was not able to be relocated for the study, therefore portable imaging equipment was used throughout. A Canon 700D DSLR camera was modified to allow nearinfrared imaging when combined with a set of longpass filters at 720 nm, 850 nm and 950 nm. An Osiris infrared reflectography camera was also used to look further into the infrared with a sensitivity range of 900 nm – 1700 nm. To obtain high-resolution images with the modified DSLR, a 100 mm lens was used from a distance of 6 metres. In both visible and near-infrared, eight images were taken across the surface of the painting and these images were combined into high-resolution visible and near-infrared panoramas. Images from the Osiris infrared camera were processed in Matlab to create a mosaic from the overview image with high-resolution regions of interest. All processed images were registered in Matlab along with the woodcut engraving of the painting shown in the Illustrated London News. An interactive web-browser viewer was created to enable display and comparison of the registered high-resolution images, allowing users to explore and zoom in to specific areas of interest across the four high-resolution images simultaneously. Conservators and art historians can utilise the resulting images combined with the image viewer to analyse the painting and potentially develop a new interpretation of the composition.

With the number of new proton centers increasing rapidly, there is a need for an assessment of the available proton treatment planning systems (TPSs). This study compares the dose distributions of complex meningioma plans produced by three proton TPSs: Eclipse, Pinnacle3, and XiO. All three systems were commissioned with the same beam data and, as best as possible, matched configuration settings. Proton treatment plans for ten patients were produced on each system with a pencil beam scanning, single‐field uniform dose approach, using a fixed horizontal beamline. All 30 plans were subjected to identical dose constraints, both for the target coverage and organ at risk (OAR) sparing, with a consistent order of priority. Beam geometry, lateral field margins, and lateral spot resolutions were made consistent across all systems. Few statistically significant differences were found between the target coverage and OAR sparing of each system, with all optimizers managing to produce plans within clinical tolerances (D295%, D99>90%, and OAR maximum doses) despite strict constraints and overlapping structures. PACS number: 87.55.D‐

Ethnopharmacological relevance/Introduction In Canada, all natural health products (NHPs) are regulated by Health Canada (HC) under the Food and Drugs Act and the Natural Health Product Regulations. All authorized products undergo pre-market assessment for safety, efficacy and quality and the degree of pre-market oversight varies depending on the risk of the product. Overview In Canada, over 70,000 products have been authorized for sale and over 2000 sites have been licensed to produce NHPs. In the management of NHPs on the Canadian market, HC employs a number of active and collaborative methods to address the most common issues such as contamination, adulteration and deceptive or misleading advertising practices. HC is currently evolving its approaches to NHPs to recognize them as part of the larger group of health products available without a prescription. As such, the regulatory responsibility for all over-the-counter (OTC) drugs, including non-prescription drugs and NHPs, has been transferred to a single federal division. Conclusion As a result of this transition a number of benefits are being realized with respect to government efficiency, clarity for industry, support for new innovations and consolidated government interactions with the Canadian market.

Opportunities to experience natural sounds are among the most important reasons for visiting parks, and mandates require that the National Park Service protect natural soundscapes. Due to its proximity to military installations, military aircraft are prevalent above Sequoia National Park, and exposure to sounds produced by aircraft have been found to detract from visitor experiences. Military overflights and associated acoustic impacts are likely to continue given Sequoia’s relationship with these agencies, and proximity to military installations, and in turn visitor experiences may be depreciated. This study examined whether educational messaging could significantly affect Sequoia visitor acceptability of military aircraft sounds, and evaluated the strengths and limitations of visitor communication strategies as they pertain to soundscape management. Results determined that informing visitors about the presence of military aircraft through a theoretically-derived message could improve acceptability of military aircraft sounds by as much as 15%. These results indicate that educational messaging may offer immediate benefits to Sequoia visitor experiences.

Visual-based research methods are commonly used to provide an empirical basis for formulating evaluative standards related to recreation use levels. Visual research methods applied in this context are subject to several potential measurement biases. This article examines two such potential biases in visual-based recreation research methods: order effect bias and range effect bias. In a lab setting, respondents evaluated recreation photographs from Rocky Mountain National Park regarding the acceptability of people at one time (PAOT). Results indicated photo presentation order and the PAOT range depicted both had an effect on photograph acceptability ratings. Potential methodological revisions to the visual-based method are discussed.

SUMMARY Aim: Information regarding the characteristics and breast cancer risk factors of British women in the standard population attending breast cancer screening is limited. Such information could be useful in personalizing screening and care, and informing and educating women about their risk. Materials & methods: Information about various breast cancer risk factors was obtained from 355 women aged between 46 and 74 years at a UK inner-city breast cancer screening clinic using questionnaires. The risk of breast cancer was calculated using the modified Gail model and analyzed using descriptive and regression statistics. Results: There were 26 women recalled for further assessment and two cases confirmed as invasive breast cancer. Forty-seven women reported first-degree relatives with breast cancer. A total of 58% of our sample was overweight or obese, although 84% reported meeting the recommended target of ≥150 min of exercise per week. A total of 44% were smokers and 23% reported consuming alcohol on a regular basis. The mean lifetime risk score was 9.0% and the mean 5-year risk score was 1.5%. Various non-Gail model risk factors were found to be correlated with risk scores, but the only factor that was significantly different between women recalled for further assessment and those who were not was age of menarche. Conclusion: The results suggest that determining risk factor data in a standard screening population could be useful both to the women, who may have modifiable lifestyle factors that can be changed to improve their risk, and to the clinics, which can identify women at a higher risk who may be unaware and not present themselves as candidates for risk assessment.

Gold nanoparticles (GNPs) may be used as a contrast agent to identify tumour location and can be modified to target and image specific tumour biological parameters. There are currently no imaging systems in the literature that have sufficient sensitivity to GNP concentration and distribution measurement at sufficient tissue depth for use in in vivo and in vitro studies. We have demonstrated that high detecting sensitivity of GNPs can be achieved using x-ray fluorescence; furthermore this technique enables greater depth imaging in comparison to optical modalities. Two x-ray fluorescence systems were developed and used to image a range of GNP imaging phantoms. The first system consisted of a 10 mm(2) silicon drift detector coupled to a slightly focusing polycapillary optic which allowed 2D energy resolved imaging in step and scan mode. The system has sensitivity to GNP concentrations as low as 1 ppm. GNP concentrations different by a factor of 5 could be resolved, offering potential to distinguish tumour from non-tumour. The second system was designed to avoid slow step and scan image acquisition; the feasibility of excitation of the whole specimen with a wide beam and detection of the fluorescent x-rays with a pixellated controlled drift energy resolving detector without scanning was investigated. A parallel polycapillary optic coupled to the detector was successfully used to ascertain the position where fluorescence was emitted. The tissue penetration of the technique was demonstrated to be sufficient for near-surface small-animal studies, and for imaging 3D in vitro cellular constructs. Previous work demonstrates strong potential for both imaging systems to form quantitative images of GNP concentration.

Regulating visitor access, in the form of user limits, on public lands is a contentious issue. Although visitor use limits have been instituted to manage a variety of recreation activities in national parks there is little research that has successfully demonstrated relationships between visitor use levels and evaluative conditions (e.g. visitor perceptions of crowding). The lack of empirical understanding of relationships between use levels and evaluative conditions brings into question the efficacy of use limits to achieve management objectives. This paper describes a research and monitoring program that identifies clear management objectives and definitive visitor use pattern relationships to manage visitor use on Half Dome in Yosemite National Park to inform the development of the Half Dome Trail Stewardship Plan that established a permit system to limit visitor use on and around Half Dome. Automated visitor counters were used to collect trail use level data and photographic documentation was used to collect people-at-one-time (PAOT) data on the cable route. Regression analyses yielded strong relationships between these data and show that 400 people per day significantly reduces crowded conditions and preserves unimpeded travel on the Half Dome cables. The approach and results developed in this project provide a basis for future monitoring to promote adaptive management of visitor use on Half Dome in order to ensure that management objectives related to quality visitor experiences and safety are met.

This chapter describes a highly collaborative project in digital humanities, which used tools and expertise from a diverse range of disciplines: medical physics, image science, and conservation. We describe this collaboration through three examples: the use of phantoms taken from medical physics, a historically accurate model of parchment degradation, and a detailed description of the steps taken to run experiments and collect data within a manageable budget. Each example highlights how procedures from a discipline were adapted for the project through collaboration. Whilst conservation focuses on developing methods to best preserve cultural heritage documents, we describe an unusual collaboration between conservation and image science to document through multispectral imaging the deliberate damage of a manuscript. Multispectral imaging has been utilised to examine cultural heritage documents by providing information about their physical properties. However, current digitisation efforts concentrate on recording documents in their current state. In this project, we aimed at recording the process of macroscopic document degradation using multispectral imaging, and the digital recovery of the writing using standard image processing methodologies. This project’s success lay in the intersection of knowledge of the processes of parchment deterioration and the specific processes that occur when a document is imaged: this has permitted us to construct a more successful and informed experiment. The knowledge acquired during the project allows us to address the issues related to the recovery of information from damaged parchment documents, and to determine which research questions can be addressed, and through which imaging methodology.

Through application of spatio-temporal regularisation techniques, we demonstrate the real-time three-dimensional dynamic reconstruction of the optical properties of a hemispherical infant head phantom, with moving absorption and scattering targets.

Noise, or unwanted sound, exposure has been shown to have a wide range of negative physical and psychological effects. Although situational context, sound characteristics, and individual expectation affect the experience of noise and its related outcomes, the personality trait of noise sensitivity also plays a critical role in assessing noise impacts. As the most widely used 21-item Noise Sensitivity Scale measure of sensitivity is often too long to administer in time-sensitive field settings, the authors conducted five studies to create and validate a shortened, field friendly version of the original, longer measure of noise sensitivity. The resulting five-item measure of noise sensitivity was shown to be internally consistent, temporally stable, highly correlated with the original measure, and predictive of noise-related outcomes such as attitudes toward specific noise, acceptability ratings of noise events, and motivations for visiting quiet locations. The applied value of the scale and implications for facilitating future research are discussed.

We present 3D optical topography images reconstructed from data obtained previously while infants observed videos of adults making natural movements of their eyes and hands. The optical topography probe was placed over the temporal cortex, which in adults is responsible for cognitive processing of similar stimuli. Increases in oxyhaemoglobin were measured and reconstructed using a multispectral imaging algorithm with spatially variant regularization to optimize depth discrimination. The 3D optical topography images suggest that similar brain regions are activated in infants and adults. Images were presented showing the distribution of activation in a plane parallel to the surface, as well as changes in activation with depth. The time-course of activation was followed in the pixel which demonstrated the largest change, showing that changes could be measured with high temporal resolution. These results suggest that infants a few months old have regions which are specialized for reacting to human activity, and that these subtle changes can be effectively analysed using 3D optical topography.

Diffuse optical imaging and spectroscopy have been extensively used to detect, diagnose and monitor cancer. This paper is a review not of cancer in general, but of the biological changes that occur that can provide contrast for near infrared (NIR) techniques. Cancer is defined by characteristics such as the development of new blood vessels, changes in metabolism and the ability to invade surrounding tissue. The sensitivity of NIR techniques to haemoglobin, water and lipid concentrations, tissue oxygen saturation and cell density means that the pathological changes that occur in malignant tissues can provide contrast between healthy and pathological tissue. Each of these contrast mechanisms are discussed in turn, with a short introduction to the physiological changes that occur, and then a review of the NIR techniques that can be used to investigate these changes and findings from published papers. The role of exogenous contrast agents with NIR techniques in cancer diagnosis and assessment are also discussed. By understanding the characteristics of cancer and the changes that occur, we can interpret our results from NIR with greater confidence and accuracy and develop new techniques that target these characteristics. Information on angiogenesis or hypoxia can be clinically useful, especially when planning treatment (hypoxia) or predicting outcome to chemotherapy (haemoglobin concentration can be used as a measure of vessel density). By understanding the characteristics of cancer and the changes that occur, we can interpret our results from NIR with greater confidence and accuracy and develop new techniques that target these characteristics.

We describe a series of novel simultaneous EEG and diffuse optical imaging studies of newborn infants. These experiments provide evidence of large, transient haemodynamic events which occur repeatedly and consistently within and across several infants with neurological damage, all of whom were diagnosed with seizures. A simple but independent process of rejecting artifacts and identifying events within diffuse optical imaging data is described, and this process is applied to data from 4 neurologically damaged neonates and from 19 healthy, age-matched controls. This method results in the consistent identification of events in three out of four of the neurologically damaged infant group which are dominated by a slow (> 30 s) and significant increase in oxyhaemoglobin concentration, followed by a rapid and significant decrease before a slow return to baseline. No comparable events are found in any of our control data sets. The importance and physiological implications of our findings are discussed, as is the suitability of a combined EEG and diffuse optical imaging approach to the study and monitoring of neonatal brain injury.

This paper presents a new numerical method for optical tomography: the combined boundary element/finite element method (BEM-FEM), designed to tackle reconstructions in layered turbid media. The BEM-FEM focuses on the region of interest by creating a volume mesh and reconstructing in this region only. All other regions are treated as piecewise constant in a surface-integral approach. We validate the model in concentric spheres, with different positions of the volume-integral treated area and found it compared well with an analytical result. We then performed functional imaging of the neonate's motor cortex in vivo, in a reconstruction restricted to the brain, both with FEM and BEM-FEM. These results show the effectiveness of the BEM-FEM in situations where the organ of interest is surrounded by superficial layers.

The use of THz radiation as a potential tool for medical imaging is of increasing interest. In this paper three methods of analysis of THz spectroscopic information for diagnosis of tissue pathologies at THz frequencies are presented. The frequency-dependent absorption coefficients, refractive indices and Debye relaxation times of pure water and pure lipids were measured and used as prior knowledge in the different theoretical methods for the determination of concentration. Three concentration analysis methods were investigated: (a) linear spectral decomposition, (b) spectrally averaged dielectric coefficient method and (c) the Debye relaxation coefficient method. These methods were validated on water and lipid emulsions by determining the concentrations of phantom chromophores and comparing to the known composition. The accuracy and resolution of each method were determined to assess the potential of each method as a tool for medical diagnosis at THz frequencies.

We have developed a novel phantom material: a solution of polyvinyl alcohol (PVAL) in ethanol and water, freeze-thawed to produce a solid yet elastically compressible gel. The x-ray attenuation and mechanical properties of these gels are compared with published measurements of breast tissue. Gels with PVAL concentrations from 5 to 20% w/v were produced. The linear x-ray attenuation coefficients of these gels range from 0.76 to 0.86 cm(-1) at 17.5 keV, increasing with PVAL concentration. These values are very similar to the published values of breast tissue at this energy, 0.8-0.9 cm(-1). Under compression cancerous breast tissue is approximately ten times stiffer than healthy breast tissue. The Young's moduli of the gels increase with PVAL concentration. Varying the PVAL concentration from 7.5 to 20% w/v produces gels with Young's moduli from 20 to 220 kPa at 15% strain. These values are characteristic of normal and cancerous breast tissue, respectively.

Diffuse optical imaging is a medical imaging technique that is beginning to move from the laboratory to the hospital. It is a natural extension of near-infrared spectroscopy (NIRS), which is now used in certain niche applications clinically and particularly for physiological and psychological research. Optical imaging uses sophisticated image reconstruction techniques to generate images from multiple NIRS measurements. The two main clinical applications—functional brain imaging and imaging for breast cancer—are reviewed in some detail, followed by a discussion of other issues such as imaging small animals and multimodality imaging. We aim to review the state of the art of optical imaging.

The development of diffuse optical tomography as a functional imaging modality has relied largely on the use of model-based image reconstruction. The recovery of optical parameters from boundary measurements of light propagation within tissue is inherently a difficult one, because the problem is nonlinear, ill-posed and ill-conditioned. Additionally, although the measured near-infrared signals of light transmission through tissue provide high imaging contrast, the reconstructed images suffer from poor spatial resolution due to the diffuse propagation of light in biological tissue. The application of model-based image reconstruction is reviewed in this paper, together with a numerical modelling approach to light propagation in tissue as well as generalized image reconstruction using boundary data. A comprehensive review and details of the basis for using spatial and structural prior information are also discussed, whereby the use of spectral and dual-modality systems can improve contrast and spatial resolution.

A solid dynamic phantom with tissue-like optical properties is presented, which contains seven discrete targets impregnated with thermochromic pigment located at different depths from the surface. Changes in absorption are obtained in response to localized heating of the targets, simulating haemodynamic changes occurring in the brain and other tissues. The depth sensitivity of a continuous wave optical topography system was assessed successfully using the phantom. Images of the targets have been reconstructed using a spatially variant regularization, and the determined spatial localization in the depth direction is shown to be accurate within an uncertainty of about 3 mm down to a depth of about 30 mm.

An electrically-activated phantom for evaluating diffuse optical imaging systems has been designed based on an array of semiconductor diodes which are used to heat a thermochromic dye embedded in a solidified polyester resin with tissue-like optical properties. The array allows individual diodes to be addressed sequentially, thus simulating the movement of a small volume of contrasting optical absorption. Two designs of diode-array phantom are described and results of imaging experiments are presented.

A novel design of solid dynamic phantom with tissue-like optical properties is presented, which contains variable regions of contrast which are activated electrically. Reversible changes in absorption are produced by localized heating of targets impregnated with thermochromic pigment. A portable, battery-operated prototype has been constructed, and its optical and temporal characteristics have been investigated. The phantom has been developed as a means of assessing the performance of diffuse optical imaging systems, such as those used to monitor haemodynamic changes in the brain and other tissues. Images of the phantom have been reconstructed using data acquired with a continuous wave optical topography system.