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Purpose/objective(s) The developing radio-immunotherapy has cast the use of radiation therapy (RT) into a pivotal role in the management of pancreatic cancer. There is a need to study pancreatic cancer in pre-clinical setting to advance our understanding of the role of RT. The challenge to study abdominal malignancy in vivo is lack of proper imaging guidance. Bioluminescence with its strong imaging contrast has been widely used to monitor tumor growth. We innovated 3D bioluminescence tomography (BLT) to guide irradiation for an orthotopic pancreatic ductal adenocarcinoma (PDAC), and monitor its growth and treatment response. Materials/methods To establish the orthotopic PDAC model, we implanted a fraction of BxPc3-Red-FLuc tumor into the pancreas of a nude mouse. For BLT, mice were subject to multi-spectral and multi-projection bioluminescence imaging (BLI), followed by small animal radiation research platform (SARRP) CBCT imaging. CBCT image was acquired to generate anatomical mesh for BLT reconstruction. We inserted a titanium wire to the center of tumor as the marker to validate the BLT localization accuracy. We will also quantify the accuracy of BLT reconstructed volume with MRI and ex vivo method. Volume-averaged bioluminescent power (BP), related to tumor viability, will also be assessed in comparing with surface BLI and ex vivo method, to determine if it is a proper metric for tumor monitoring and assessment. We will further irradiate the in vivo PDAC volume guided by BLT and demonstrate the application of BLT to longitudinally assess the change of PDAC volume/power in response to treatment. Results Our initial result shows 3D BLT can retrieve the orthotopic PDAC location within 1.5 mm accuracy at depth from 3-5 mm, common depth observed in pancreatic study. The BP is observed linearly by 12-fold along the tumor growth 4 weeks after tumor implantation. With BLT, we are able to reconstruct the 3D bioluminescent tumor volume using multiple-projection imaging. Conclusion The quantitative BLT system offers unique opportunities for researchers to study important pancreatic tumor in orthotopic setting to quantify its location, growth and response to therapeutic intervention.

PURPOSE/OBJECTIVE(S) To advance image-guided irradiation for soft tissue targeting and treatment assessment, we collaborated with our industrial partner and developed a bioluminescence tomography system (BLT, MuriGlo) for pre-clinical radiation research. We characterize the system performance and demonstrate its capability in target localization for radiation guidance. MATERIALS/METHODS MuriGlo consists of four-mirror system, filters, lens and CCD camera, enabling a compact imaging platform and multi-projection and multi-spectral BLT. The imaging mouse bed includes a base, and a detachable and transportable bed, allowing animal imaged in MuriGlo and transferred to small animal radiation research platform (SARRP) for CBCT imaging and BLT-guided irradiation. A transparent polycarbonate plate covering the middle of the mouse bed is used to support and image animal at 1800 projection under the bed. We investigated its effects on optical signal acquisition, 3D BLT reconstruction accuracy and dosimetric impact. Imaging phantoms are designed to evaluate 2D imaging resolution, focal plane, depth of field, signal acquisition linearity, imaging uniformity and distortion. An optimization routine with pinhole camera model was developed to map 2D bioluminescence images (BLIs) to the surface of the numerical mesh of imaged object generated from the CBCT image. The mapped BLIs are used as input data for BLT reconstruction. Spectral derivative method with compressed sensing conjugate gradient algorithm was implemented for BLT volumetric reconstruction. To minimize the ambient temperature in affecting in vivo bioluminescence signal intensity and spectrum, a temperature control module was also developed to maintain consistent temperature in the MuriGlo imaging chamber. Phantom and glioblastoma (GBM) mouse model will be used to validate the localization accuracy of the BLT system for guidance. RESULTS The depth of field of MuriGlo was measured at 24mm, and the focal plane is set at 16mm above the mouse bed to have clear surface BLIs of mouse at all projections. The linearity between signal and exposure time from 0.1 to 180s is within 0.6% deviation. Our initial test shows within a given region of interest, the image uniformity is within 5% variation and image shift due to distortion is within 0.25mm. The data mapping from the 2D BLIs to 3D CBCT image is within 0.6mm. With temperature control turned on, the imaging chamber could be warmed up to 37°C from room temperature in 13 mins. Our phantom test shows MuriGlo can localize 3D bioluminescent target at 1mm accuracy and only 0.2mm deviation was observed for the case with and without transparent plate. CONCLUSION This work is the first systematic study in characterizing the commercial BLT-guided system for pre-clinical radiation research. We expect the information and methods developed in this study will support MuriGlo users, cross different institutes, in performing accurate image-guided radiation research and facilitating study reproducibility.

Objectives Functionalised silica sub-micron particles are being investigated as a method of delivering antimicrobials and remineralisation agents into dentinal tubules. However, their methods of application are not optimised, resulting in shallow penetration and aggregation. The aim of this study is to investigate the impact of cavitation occurring around ultrasonic scalers for enhancing particle penetration into dentinal tubules. Methods Dentine slices were prepared from premolar teeth. Silica sub-micron particles were prepared in water or acetone. Cavitation from an ultrasonic scaler (Satelec P5 Newtron, Acteon, France) was applied to dentine slices immersed inside the sub-micron particle solutions. Samples were imaged with scanning electron microscopy (SEM) to assess tubule occlusion and particle penetration. Results Qualitative observations of SEM images showed some tubule occlusion. The particles could penetrate inside the tubules up to 60 μm when there was no cavitation and up to ∼180 μm when there was cavitation. Conclusions The cavitation bubbles produced from an ultrasonic scaler may be used to deliver sub-micron particles into dentine. This method has the potential to deliver such particles deeper into the dentinal tubules. Clinical significance Cavitation from a clinical ultrasonic scaler may enhance penetration of sub-micron particles into dentinal tubules. This can aid in the development of novel methods for delivering therapeutic clinical materials for hypersensitivity relief and treatment of dentinal caries.

Wave breaking occurs when waves reach a critical level of amplitude, which results in releasing a significant amount of energy. Predicting the wave heights, locations and other characteristics of breaking waves in shallow water is an important area of research. The breaking wave height, which is the most important characteristic, depends on various parameters such as deepwater wavelength, breaking water depth and seabed slope. In this study, new formulae are proposed for predicting the breaking wave height focusing on two types of breaking waves, namely spilling and plunging. The breaking wave types can be classified by using the Iribarren number. A comprehensive set of laboratory and field observations is utilized to develop new formulae based on the Gene Expression Programming (GEP) numerical method. The datapoints representing individual waves whose breaking types have been determined to be different according to different wave breaking classification criteria have been ignored. In comparison with previous formulae, the new formulae proposed based on different breaking types have almost higher accuracy, especially in the plunging case. Therefore, it might be concluded that developing different formulae based on different breaking types, rather than a general one for all types, would lead to more accurate results.

Some regions of the world suffers of drought which affects plant behavior regarding biochemical and yield responses. This study aimed to estimate the general and specific combining abilities of coriander ( Coriandrum sativum L.) by analyzing its fruit yield, essential oil content (EOC) and fatty oil content (FOC). To reach this aim, 15 half-diallel hybrids and their six parents, selected for their different response to water stress in fruit yield, essential oil and fatty oil content were evaluated under well-watered, moderate water-stressed and severe water-stressed conditions in the field and in glasshouse cultivation systems. Fruit yield in the field (FYF) and glasshouse (FYG), percent of de-hulled fruit, percent of hulls, EOC, essential oil yield (EOY), de-hulled fruit fatty oil content (DFFOC), hull fatty oil content (HFOC), fatty oil content (FOC) and fatty oil yield (FOY) were examined. Water treatment (WT), genotype and genotype × WT effects were significant (P ≤ 0.01) for all measured traits. For FYF, gene action was mostly additive while dominance was more important for FYG. Genotypes gained different EOC and FOC in different WTs. Genetic control of the EOC was affected by water stress and the portion of dominance in gene action increased as water stress progressed leading to completely dominant genetic control of EOC under severe water stress. For FOC and FOY genetic control was governed by dominant and over dominant gene nature in all WTs. Parents including P 1 , P 4 and P 6 were indicated as promising hybrid contributors for high EOC, DFFOC and FOY. Similar genetic control mechanisms of the EOC, EOY, FOC and FOY suggests that improvement of essential oil content and fatty oil content could be simultaneously achieved in coriander.

Drought is a worldwide problem seriously influencing production of agricultural plants such as coriander, but development of tolerant genotypes is inhibited by a lack of effective selection criteria. The objective of this study was to interpret the relationship between fruit yield and related traits in coriander to evaluate genotype by trait interaction by considering genotype × irrigation interaction. According to this aim, 16 Iranian endemic coriander genotypes were grown in a glasshouse under well watered (WW) and water stressed (WS) conditions. Structural equation modeling (SEM) was used, based on genotypic correlation coefficients and genotypic variance estimates obtained from combined analysis of WW and WS conditions and genotype-trait (GT) biplot analysis. Applying both types of analyze to the multiple trait data revealed that SEM and DC + YPr data based GT biplot results are similar. The GT biplot graphically displayed the interrelationships among traits and facilitated visual comparison of genotypes for selection. Predictors in the causal diagram could explain 70.8%, 80.9%, 100% and 41.7% of the total variation in fruit weight per plant (FWPP), fruit number per plant (FNPP), day to end of flowering (DTEOF) and umbel number per plant (UNPP), respectively. Also, the GT biplots explained 81.2% for WW data, 74% for WS data and 79.7% for DC + YPr data. It was found that selection for high SPAD chlorophyll content in the grain filling stage (SCCIGFS), UNPP, FNPP and branch number per plant (BNPP), and low shoot dry weight per plant (SDWPP) and DTEOF should be considered as priorities in breeding programs for coriander aiming for more productive and drought tolerant genotypes. Furthermore, G13 (TN-59-353) can be used as a drought tolerance donor in breeding programs.

Stereotactic neurosurgical robots allow quick, accurate location of small targets within the brain, relying on accurate registration of pre-operative MRI/CT images with patient and robot coordinate systems during surgery. Fiducial markers or a stereotactic frame are used as registration landmarks; the patient's head is fixed in position throughout surgery. An image-based system could be quicker and less invasive, allowing the head to be moved during surgery to give greater ease of access, but would be required to retain a surgical precision of ∼1 mm at the target point. We compare two registration algorithms, iterative closest point (ICP) and coherent point drift (CPD), by registering ideal point clouds taken from MRI data with re-meshed, noisy and smoothed versions. We find that ICP generally gives better and more consistent registration accuracy for the region of interest than CPD, with a best RMS distance of 0.884±0.050 mm between aligned point clouds, as compared to 0.995±0.170 mm or worse for CPD.

We developed and validated a new optical mapping system for quantification of electrical activation and repolarisation in murine atria. The system makes use of a novel 2nd generation complementary metal-oxide-semiconductor (CMOS) camera with deliberate oversampling to allow both assessment of electrical activation with high spatial and temporal resolution (128 × 2048 pixels) and reliable assessment of atrial murine repolarisation using post-processing of signals. Optical recordings were taken from isolated, superfused and electrically stimulated murine left atria. The system reliably describes activation sequences, identifies areas of functional block, and allows quantification of conduction velocities and vectors. Furthermore, the system records murine atrial action potentials with comparable duration to both monophasic and transmembrane action potentials in murine atria.

Functional neuroimaging commands a dominant role in current neuroscience research. However its use in bedside clinical and certain neuro-scientific studies has been limited because the current tools lack the combination of being non-invasive, non-ionizing and portable while maintaining moderate resolution and localization accuracy. Optical neuroimaging satisfies many of these requirements, but, until recent advances in high-density diffuse optical tomography (HD-DOT), has been hampered by limited resolution. While early results of HD-DOT have been promising, a quantitative voxel-wise comparison and validation of HD-DOT against the gold standard of functional magnetic resonance imaging (fMRI) has been lacking. Herein, we provide such an analysis within the visual cortex using matched visual stimulation protocols in a single group of subjects (n = 5) during separate HD-DOT and fMRI scanning sessions. To attain the needed voxel-to-voxel co-registration between HD-DOT and fMRI image spaces, we implemented subject-specific head modeling that incorporated MRI anatomy, detailed segmentation, and alignment of source and detector positions. Comparisons of the visual responses found an average localization error between HD-DOT and fMRI of 4.4 +/− 1 mm, significantly less than the average distance between cortical gyri. This specificity demonstrates that HD-DOT has sufficient image quality to be useful as a surrogate for fMRI.

This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length (CGL) and cooked grain shape (CGSH). General combining ability (GCA) and specific combining ability (SCA) effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA × environment interaction effects were significant for CGL, CGSH and grain elongation index (GEI). In the controlling of the inheritance of milled grain shape (GSH), milled grain width (MGW), GEI, milled grain length (MGL), CGSH and cooked grain width (CGW), the additive gene effects were more important than non-additive one. The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 (GSH) to 0.36 (CGL). GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.

Materials and Methods. A new spectral reconstruction method that is considered to provide the most accurate estimates of hemoglobin level, oxygen saturation, water fraction, scattering power, and amplitude was used to assess healthy breast tissue imaged in vivo by means of NIR tomography. The approach directly recovers functional parameters with inherent inclusion of spectral behavior enforced through the incorporation of a priori model assumptions. Sixty subjects were imaged by using a frequency-domain instrument followed by spectral image reconstruction and statistical analysis for significant correlations. Results. The new analysis shows statistically significant inverse correlations between body mass index and breast total hemoglobin and water fractions. Water fraction also correlated inversely with age and separated certain categories of breast density. Average scatter power was indicative of breast radiographic density composition, whereas scatter amplitude varied inversely with breast diameter. Total hemoglobin correlated with water fraction, whereas water correlated with scatter power. Conclusion. The changes observed here are attributable to volume fraction alterations and provide some of the most comprehensive data on breast composition variations with demographic factors.

Background A reliable portable non-invasive monitor for use in brain injury is needed, so near infrared spectroscopy (NIRS) has potential. Historical inconsistencies in NIRS have prevented its use, often attributed to the contamination of signal from extracranial tissue. We aimed to validate the brain signal from frequency domain NIRS (advanced NIRS technique), comparing its abilities with functional MRI (fMRI) to isolate physiological activity in the brain from those of extracranial tissue. Methods In a prospective healthy volunteer study, nine individuals (six male, three female, age range 21–40 years) performed supine Valsalva manoeuvres (adequacy monitored via finger photoplethysmography and capnography). The Valsalva manoeuvre provided a suitable model for cerebral ischaemia and rises in intracranial pressure. During the manoeuvre, a portable frequency domain NIRS device was targeted separately at the brain and at extracranial tissue, and fMRI (blood oxygen load dependent sequence) was taken from regions corresponding to both fields of NIRS acquisition. Area under the curve analysis of the change in variables during the Valsalva manoeuvre was analysed by the Wilcoxon rank sum method with multiple pairwise comparisons between the brain and extracranial tissue signals for both NIRS and fMRI. Findings We observed similar responses in both brain and extracranial tissue: in all volunteers, oxygenation in brain tissue during the Valsalva manoeuvre decreased (mean −7·2% NIRS [SD 4·7], −3·4% fMRI [SD 1·46]) and oxygenation from the extracranial acquired data increased (mean +6·1% NIRS [SD 2·72], +4·4% fMRI [SD 3·45]), matching physiological predictions. These brain and extracranial signals were significantly different in both fMRI and NIRS (p=0·00025 and 0·00115, respectively). Interpretation Our findings confirm that frequency domain NIRS can detect specific changes within the brain tissue during the Valsalva manoeuvre independent of physiological features of extracranial tissue and reflects changes observed by fMRI. Therefore, the frank changes in the brain observed by frequency domain NIRS are brain specific, demonstrating the potential for this method to be used within the context of brain injury. Funding National Institute for Health Research Surgical Reconstruction and Microbiology Research Centre.