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In this work we demonstrate, to the best of our knowledge, a novel wide field-of-view upconversion system, supporting upconversion of monochromatic mid-infrared (mid-IR) images, e.g., for hyperspectral imaging (HSI). An optical parametric oscillator delivering 20 ps pulses tunable in the 2.3–4 μm range acts as a monochromatic mid-IR illumination source. A standard CCD camera, in synchronism with the crystal rotation of the upconversion system, acquires in only 2.5 ms the upconverted mid-IR images containing 64 kpixels, thereby eliminating the need for postprocessing. This approach is generic in nature and constitutes a major simplification in realizing video-frame-rate mid-IR monochromatic imaging. A second part of this paper includes a proof-of-principle study on esophageal tissues samples, from a tissue microarray, in the 3–4 μm wavelength range. The use of mid-IR HSI for investigation of esophageal cancers is particularly promising as it allows for a much faster and possibly more observer-independent workflow than state-of-the-art histology. Comparing histologically stained sections evaluated by a pathologist to images obtained by either Fourier transform IR or upconversion HSI based on machine learning shows great promise for further work pointing towards clinical translation using the presented mid-IR HSI upconversion system.

Atrial ectopic beats are recognised triggers for atrial fibrillation (AF). Ectopic foci are potential therapeutic targets for catheter ablation. This study examined the frequency and timecourse of atrial ectopy in [...]

Osteoporosis is clinically assessed from bone mineral density measurements using dual energy X-ray absorption (DXA). However, these measurements do not always provide an accurate fracture prediction, arguably because DXA does not grapple with ‘bone quality’, which is a combined result of microarchitecture, texture, bone tissue properties, past loading history, material chemistry and bone physiology in reaction to disease. Studies addressing bone quality are comparatively few if one considers the potential importance of this factor. They suffer due to low number of human osteoporotic specimens, use of animal proxies and/or the lack of differentiation between confounding parameters such as gender and state of diseased bone. The present study considers bone samples donated from patients (n=37) who suffered a femoral neck fracture and in this very well defined cohort we have produced in previous work fracture toughness measurements (FT) which quantify its ability to resist crack growth which reflects directly the structural integrity of the cancellous bone tissue. We investigated correlations between BV/TV and other microarchitectural parameters; we examined effects that may suggest differences in bone remodelling between males and females and compared the relationships with the FT properties. The data crucially has shown that TbTh, TbSp, SMI and TbN may provide a proxy or surrogate for BV/TV. Correlations between FT critical stress intensity values and microarchitecture parameters (BV/TV, BS/TV, TbN, BS/BV and SMI) for osteoporotic cancellous tissue were observed and are for the first time reported in this study. Overall, this study has not only highlighted that the fracture model based upon BMD could potentially be improved with inclusion of other microarchitecture parameters, but has also given us clear clues as to which of them are more influential in this role.

AbstractWe conducted an outdoor feeding trial with Golden Shiners Notemigonus crysoleucasusing diets with 22% or 28% protein from different sources. The 28% protein diet with soybean (SOY) meal was the control, and the three other diets contained 22% protein mainly from SOY, corn gluten feed (CGF), or corn distillers dried grains with solubles (DDGS). The 22% protein SOY diet was also offered as a meal or pellet in separate treatments. Each of the five diets was fed to fish at two densities: 250,000 fish/ha (low density) or 750,000 fish/ha (high density). Fish with an initial weight of 0.25 ± 0.003 g (mean ± SE) were stocked into four 4.1-m3pools per treatment and fed daily to apparent satiation for 9 weeks. Diet effects were assessed by measuring growth, survival, feed conversion, condition index, and body composition. An enterprise budget analysis was conducted to determine the economic effects of different treatments. Fish weight gain was higher at the low density regardless of diet. Weight gain was also higher in fish fed the diet with 28% protein than in those fed other diets at either density. Relative weight (Wr) was higher at the high density and in fish fed the SOY diets compared with those fed the CGF or DDGS diets. Survival was higher at the high density, and no diet effects were apparent. Gross yield was higher at the high density and in the 28% protein SOY control. Feed conversion ratio was better at the low density. Whole-body lipid was higher in fish at the low density. The most economically beneficial diet was the 28% protein SOY diet, but producers must consider feed choice in the context of their overall business model. The 22% protein diets were inadequate for rapid growth, but did not compromise survival, indicating a possible use for maintenance feeding when fish reach market size.Received August 30, 2013; accepted November 5, 2013

The vibrational spectroscopy techniques of Raman spectroscopy and Fourier-transform infrared spectroscopy offer a number of potential advantages as tools for clinical diagnosis. The ability of these methods to detect subtle biochemical changes relating to pathology opens the possibility of their use in tissue diagnosis. Potential applications include use as an ‘optical biopsy’ technique for in vivotissue diagnosis or to guide therapy, as a ‘digital staining’ method to assist a histopathologist in analysing a sample, or as an entirely automated process for histopathology classification. To date, much work has been undertaken in applying these spectroscopic methods to discriminate between disease states across a wide range of pathologies and organ systems, but as yet none have entered routine clinical practice. There is a pressing clinical need for real-time, accurate tissue diagnosis, especially in malignant conditions for which rapid diagnosis and comprehensive identification and treatment of diseased tissue are of paramount importance. Cancer diagnostics remains reliant on analysis of tissue samples by histopathologists to confirm malignancy, based on morphological tissue changes and immunohistochemical staining techniques. There is increasing evidence that vibrational spectroscopy, in combination with chemometric data analysis, is a powerful and accurate technique for detecting cancerous and pre-cancerous biochemical changes both in vitroand in vivo, for a range of malignant conditions. This review examines the progress of vibrational spectroscopy towards selected clinical applications, with a particular focus on cancer diagnostics.

Multivariate classifiers (such as Linear Discriminant Analysis, Support Vector Machines etc) are known to be useful tools for making diagnostic decisions based on spectroscopic data. However, robust techniques for assessing their performance (e.g. by sensitivity and specificity) are vital if the application of these methods is to be successful in the clinic. In this work the application of repeated cross-validation for estimating confidence intervals for sensitivity and specificity of multivariate classifiers is presented. Furthermore, permutation testing is presented as a suitable technique for estimating the probability of obtaining the observed sensitivity and specificity by chance. Both approaches are demonstrated through their application to a Raman spectroscopic model of gastrointestinal cancer.

Raman spectroscopy is an inelastic scattering technique capable of probing the biochemical changes associated with neoplastic progression in oesophageal tissue. Custom-built fibre-optic Raman probes could potentially provide opportunities for in vivo endoscopic diagnosis of pre-cancerous oesophageal lesions and targeted early therapy. However, prior to commencing a clinical trial convincing ex vivo work must demonstrate multi-operator, multi-centre and multi-system reliability. We report spectral consistency between two operators who independently evaluated two optically identical probes ex vivo. In addition, we demonstrate compatibility with high-definition white light endoscopes and narrow band imaging systems highlighting the potential for future endoscopic multi-modality imaging in the oesophagus.

Groundwater models are used to manage water resources in carbonate aquifers throughout the UK. These models often utilize non-linear modifications of equivalent porous media (EPM) assumptions to simulate the observed head-flow relationships. This paper describes the application of similar principles to time-variant water balance modelling of a karstified aquifer: the Carboniferous Limestone in SW England. The non-linear model successfully simulates the large changes in bulk hydraulic conductivity required to adequately model flows from two karstic spring catchments. Model results illustrate that the rate of drainage from the vadose zone is affected by the extent and thickness of soil cover. In a catchment with mixed soil cover, vadose zone drainage is shown not to be significant in sustaining summer low flows at the spring. The performance of the model is limited in some cases: summer storm flows in particular are poorly simulated. The limitations suggest that the true response of the system is dependent on recharge intensity (rate) as well as antecedent water levels and that the EPM assumption of good connection between conduits and the diffuse flow zone is not always valid in this aquifer. This may have implications for groundwater model design in other carbonate aquifers.

ABSTRACTA 65-year-old diabetic female presented with a 3-week history of a left swollen foot after a minor inversion injury and was found to have a minimally displaced fibular fracture. Despite casting and strict instructions to remain non-weight bearing, the patient continued to bear weight and later developed a significantly more displaced fracture with a draining ulcer. This injury eventually required a tibiotalocalcaneal arthrodesis using a retrograde hindfoot nail. Neuropathy and neuropathic fractures can be devastating complications of diabetes and thus require early diagnosis and intervention because they may result in significant morbidity for the patient. Thorough assessment involving imaging, a complete history and physical examination, and tools such as a 129 Hz tuning fork and the 10 g Semmes- Weinstein monofilament are paramount to establishing an accurate initial diagnosis. These tactics aid in future followup of the patient's injury and can be employed in both the clinic and the emergency department. Although management remains controversial for neuropathic ankle fractures because both conservative and surgical treatment regimens have high complication rates, open reduction and internal fixation continues to be the treatment of choice once closed reduction has been attempted and fails. Education is essential because diabetic patients have compromised pain and pressure sensation, which can lead to injuries and subsequent complications of which they are simply unaware. Physicians must be diligent when evaluating the diabetic foot and be explicit when providing instructions to these patients because preventing these injuries and their complications is the best patient care available.

Histopathology provides the gold standard assessment of colonoscopic biopsies. Infrared spectroscopy can potentially map biochemical changes across a tissue section identifying disease. The purpose of this study was to determine if infrared spectroscopy could classify different colorectal pathologies and to investigate biochemical composition. Colonoscopic tissue biopsies were snap frozen at colonoscopy. 10 micron thick sections were mounted on CaF2slides. 3- D spectral datasets (2 spatial dimensions and one spectral) were measured from thawed specimens using a Perkin Elmer infrared imaging system in transmission mode. Contiguous tissue sections stained with H&E were reviewed by a specialist gastrointestinal pathologist for comparison. Tissue spectra from epithelial tissues were classified using principal components fed linear discriminant analysis with leave one out cross validation. Reference spectra from purchased biochemicals (Sigma-Aldrich) were measured. Ordinary least squares analysis estimated the relative biochemical signal contribution from epithelial regions. Spectra from tissue epithelia measured from normal tissue, hyperplastic polyps, adenomatous polyps, cancer and ulcerative colitis samples were classified with accuracies in excess of 90%. Ordinary least squares analysis demonstrated a higher DNA to cytoplasm ratio in cancer compared to normal tissue. FTIR spectra from epithelia can be used to classify colorectal pathologies with high accuracy. Ordinary least squares analysis shows promise for extraction of useful biochemical information. These techniques could aid the histopathologist and ultimately lead to automated histopathological processing.

The Arkansas baitfish industry leads the nation in production of golden shiners Notemigonus crysoleucas. To determine nutritional requirements for golden shiner broodstock diets, we examined the volume and lipid, fatty acid, and amino acid composition of the eggs produced by a group of captive broodstock over a spawning season. Egg volume was 0.67 ± 0.117 mm3(mean ± SD); egg volume declined during the spawning season. Total lipid was 15.67 ± 2.99 µg/egg, and triacylglyceride (TAG) concentration was 6.82 ± 1.81 µg/egg. Based on the stability of egg total lipid, the percent neutral lipid, the consistent contribution of TAG to neutral lipid, the consistent TAG concentration, and the stable fatty acid and amino acid profiles, we conclude that the lipid and amino acids in eggs from the experimental group were stable. The eggs should be equally sufficient for embryological development throughout the spawning season, but specific indices of egg and fry quality must be measured to confirm the links among egg size, biochemical composition, and egg and fry quality.

The cations Ca2+and Mg2+are two important factors in the growth and maintenance of living cells. The addition of Ca2+to living cells can cause a change in the three-dimensional (3D) structure of calcium binding proteins. Therefore, we decided to study whether the addition of CaCl2and MgCl2to three in vitrogrowing lung cancer cell lines could cause changes that could be measured by Fourier Transform Infrared Spectroscopy. The addition of CaCl2or MgCl2to lung cancer cells caused an increase in absorbance of the trough at 1410 cm−1. This translated into an inversion of the 1410/1395 cm−1ratio following the addition of CaCl2or MgCl2for all three lung cancer cell lines. Also, the amide I peak shifted from around 1631 cm−1to lower wavenumbers when CaCl2or MgCl2was added to cancer cells. Furthermore, the addition of these two substances caused a shift of the peak between 3290 and 3395 cm−1. Finally, while the addition of CaCl2to lung cancer cells was associated with an increased cell death, this was not the case following the addition of MgCl2. This would confirm that the changes seen in the spectra of all three cell lines are due to metabolic and ionic shifts rather than cell death.

This paper is the first reported description of Raman Spectroscopy in the assessment of axillary lymph nodes in breast cancer patients. Raman Spectroscopy is an inelastic scattering spectroscopic technique appropriate for the assessment of unprocessed complex biological tissues. Spectra represent biochemical signatures of the tissue under scrutiny. The described method of Raman spectral mapping produces false-color spectral images of lymph node sections. These can be compared with standard histopathology slides and white light images of nodal tissue. This method has the potential to allow the detailed biochemical assessment of heterogeneous lymph node features, and to contribute towards the development of an optical diagnostic tool for use in a clinical setting.

A large reinforced concrete structure supported on piles extending to bedrock is evaluated using a seismic soil-structure interaction analysis. The physical structure, the supporting pile system, analysis model and analytical methodology used are described. Important considerations in the design of the foundation pile system using the seismic analysis loadings and deformations are discussed.

Abstract: We report a programme of novel experiments involving direct proton emission and β-delayed proton and neutron emission for exotic nuclei oriented at low temperatures. Full modelling of the quantum tunneling and angular distribution has been made for the first time for these processes. Their study has application in many fields of natural science. The study of barrier effects involving angular momentum and non-spherical deformation can be approached more directly via single-particle emission than via alpha decay, which suffers from complications relating to preformation of the alpha particle. Using the new formalism, predictions are presented for angular distributions of β-delayed neutrons from oriented 137I and of direct proton emission from oriented 147Tm.

The nuclear spin–lattice relaxation of 127In implanted into pure gadolinium metal has been measured using the method of integral attenuation of on-line nuclear orientation. The Korringa constant is determined to be CK(127InGd, Bpol= 0.5 T) = 0.133(18) sK. The result is compared with relaxation of In nuclei inFe.

New results on the applied field dependence of the NMR of 75Se implanted in pure iron and oriented at millikelvin temperatures are reported. They yield the magnetic hyperfine field acting on Se nuclei present as dilute impurities in the iron matrix and the magnetic dipole moment of the 5/2+ground state of 75Se with significantly improved precision. The results are Bhf(SeFe) =+67.9(10)T and |μ|(75Se) =0.683(10)μN. The improved value of the hyperfine field, with data from[2], gives the magnetic dipole moment of the 9/2+ground state of 73Se as |μ|=0.892(13)μN.

NFB42 (neural F Box 42 kDa) is a novel gene product that is highly enriched in the nervous system. Its predicted protein contains an F box, a motif recently shown to couple cell cycle regulation to the proteasome pathway (Bai, C., Sen, P., Hofmann, K., Ma, L., Goebl, M., Harper, J. W., and Elledge, S. (1996) Cell 86, 263-274). NFB42 mRNA and protein are expressed in all major areas of the adult rat brain but are not detected in non-neural tissues. NFB42 protein is localized primarily to the cytoplasm of neurons and does not appear to be present in glia. The presence of an F box in NFB42 suggests that it may be involved in cell cycle regulation; however, its expression in postmitotic neurons indicates that it is not involved in regulating typical cell cycle events. In an initial attempt to characterize the function of this protein, NFB42 was transfected into N1E-115 neuroblastoma and Chinese hamster ovary cells. The expression of full-length NFB42, but not an F box deletion mutant, inhibits proliferation in both cell lines. Additional experiments demonstrate that NFB42 interacts with Skp1p, a component of the proteasome pathway, and deletion of the F box also inhibits this interaction. Overall, the expression pattern of NFB42, along with the presence of an F box domain and the ability to inhibit growth, suggests that it may play a role in maintaining neurons in a postmitotic state.

Abstract: Properties of the decay of136Cs to136Ba are deduced from low temperature nuclear orientation studies. Of particular interest is the observation of attenuated anisotropy in transitions from the 7- 0.3s isomer at 2031 keV. This is ascribed to the presence of mixed electric/magnetic interaction in this state which is not collinear with the parent136Cs quantisation axis.

Abstract: The magnetic dipole moments of212Bi and213Bi have been measured and the results are interpreted within the framework of the shell model.

Abstract: The performance of two external plastic scintillator detectors has been tested in an off-line mode using a source of106RuFe at UNISOR/NOF. The measurement of beta asymmetries at various temperatures has resulted in the reproduction of the previously-determined magnetic dipole moment for the 1+ ground state of106Rh and in addition the conclusion that the sign of this moment is positive.

Abstract: The magnetic hyperfine splitting frequencies of123INi,124INi and131INi in a zero external magnetic field have been determined by the NMR-ON method as 258.9(1), 165.9(1) and 179.5(2) MHz, respectively. With the known values of the magnetic moments, the magnetic hyperfine fields have been deduced:B HF(123INi)=30.17(5) T,B HF(124INi)=30.14(9) T,B HF(131INi)=30.06(4) T; the weighted average isB HF(INi)=30.11(4) T. The small difference of theB HF(131INi) with those of123INi and124INi is discussed comparing with results of the hyperfine splitting frequency of iodine in iron host.

Abstract: This paper introduces the principles of a new method of making on-line nuclear orientation (OLNO) experiments. The source is pulsed and nuclear spin lattice relaxation is observed directly through the growth of anisotropy of angular distribution of emitted radiation with time after implantation. It is shown that Time Resolved studies (TR-OLNO) are necessary if useful analysis of orientation experiments is to be possible when relaxation times and half-lives become comparable. In the application of OLNO to decays following the initial implant, use of TR-OLNO can overcome difficulties which arise when polarisation is inherited from precursors in the decay chain. Such inheritance introduces ambiguity into analysis of continuous implantation, Time Integral (TI-OLNO), data. Two important features of the new method are discussed. TR-OLNO relaxation rates are sensitive measures of the nuclear g-factor, and combined with TI-OLNO can yield both nuclear spin and magnetic moment. A second feature is the ability to simplify complex spectra, to establish assignments of transitions to members of a decay chain with clarity and to establish the presence of long lived isomers. Experiments performed with TR-OLNO are briefly reviewed.

Abstract: The magnetic dipole moment of114Sb has been measured using on-line nuclear orientation (OLNO) at the UNISOR Nuclear Orientation Facility (UNISOR/NOF). The value was determined to be 1.72 (8) nuclear magnetons. The observed anisotropy of the 1299 keV transition was fitted as a function of temperature making allowance for incomplete thermalization of the114Sb nuclei prior to decay. The relaxation constant, Ck, is discussed, as is the ground state structure of114Sb.

Abstract: Low-temperature nuclear orientation measurements made on-line at the SERC Daresbury Laboratory on142m Eu,141m Sm, and141Pm, with known magnetic dipole moments, have yielded the magnitude of the hyperfine fields of these isotopes in an iron host lattice. Thus measurements for the isotopes139, 138Eu,139m Sm, and138Pm yielded values for the respective magnetic moments. Limits on the thermal relaxation times of Eu and Sm isotopes in Fe were also deduced. The results for138Eu appear to contradict the earlier πh11/2⊗νh11/2 ground-state configuration assignment.

Abstract: Assignments for the principal Nilsson configuration in light β+-decaying bromine isotopes were proposed in a contribution to the OLNO-1 conference. These assignments were made on the basis of magnetic moments derived from the temperature dependence of anisotropies in daughter Se isotopes observed in the DOLIS-COLD facility at Daresbury. Anisotropy measurements have since been extended to a lower base temperature in74m Br and72g Br decay, leading to more stringent limits on the ground state moment of72Br. The proposed π[312]3/2 configuration for75Br has also now been confirmed by a measurement of the sign of its magnetic moment. This was done by observing the β-asymmetry in75Br decay using high purity Si detectors mounted within the dilution refrigerator.

Abstract: A low temperature nuclear orientation experiment has been performed on the 14.8d225Ra activity. Gamma anistotropy [221Fr (4.8m) and213Bi (45.6m)] and alpha anisotropy [225Ac (10.0d),221Fr,217At (32.3ms) and209Po (4.2μs)] measurements has been carried out and values for the hyperfine field of225Ac and221Fr in iron and the magnetic moment of213Bi are reported.

Low temperature nuclear orientation and nuclear magnetic resonance (NMRON) have been used to measure the magnetic hyperfine interaction in96TcFe and the decay scheme properties of96Tc. The spin of the96Tc ground state is confirmed as 7. Its magnetic moment µ(96Tc)=5.37±0.17 n.m. The magnetic hyperfine field for96TcFe is -298±10 kOe. The anisotropies of the 778, 813, 850 and 1126 keV transitions in96Mo agree with pure E2 multipolarity assignments. The spin-parity of the 2876 keV level is 7+.

Recent developments in nuclear orientation (NO) and radiative detection of NMR (NMR/ON) are reviewed. Details of the hyperfine interaction hamiltonian in cubic ferromagnets and the principles of measurement by these techniques of both magnetic dipole and electric quadrupole terms are outlined. In the experimental survey a full account is given of measurements of the electric quadrupole interaction by frequency modulated and fast passage NMR/ON, with briefer coverage of applications of both techniques to implanted systems, of linewidths, concentration dependent line structure, and Knight shifts in NMR/ON and of NO measurements of electric quadrupole interactions in non-cubic non-magnetic metals. The review incorporates a tabulation of NMR/ON measurements to date.

The nuclear magnetic moment of103Ru has been determined using the technique of low-temperature nuclear orientation on103Ru as a dilute impurity in Fe. The Fe lattice was cooled to 1.7 mK using a PrNi5 enhanced nuclear demagnetisation stage precooled with a3He-4He dilution refrigerator. The103RuFe system was observed to have a long nuclear spin-lattice relaxation time, but analysis of the relaxation indicates that the103Ru nuclei are close to thermal equilibrium with the Fe lattice at times>200 min after demagnetising. From the near thermal equilibrium anisotropy of the 497 keV ?-ray in103Rh we have deduced the nuclear magnetic moment as |µ(103Ru)|=0.18(2)µN. This value is almost independent of the choice of spinI=3/2 or 5/2 for the nucleus, but is only consistent with systematics ifI(103Ru)=3/2 and µ<0. UsingI=3/2 we obtain the E2/M1 mixing ratio of the 497 keV ?-ray as d=-0.42(4). The sign of the anisotropy of the 610 keV ?-ray from the 650 keV level in103Rh is only consistent with an allowed ß-decay to the state ifI(650 keV,103Rh)=5/2. The E2/M1 mixing ratio of the 610 keV ?-ray is then d=+0.15(3) or +60(-40+8), <-80. From the initial rise in ?-ray anisotropy following demagnetisation we determine the Korringa constant for103RuFe to beC=5.7(5) K·s.

The half-lives of184Ir,185Ir and186Ir have been determined to be 3.14(2) h, 14.4(1) h and 16.64(3) h, respectively. The quadrupole frequenciesvQ = e2qQs/h of184Ir and185Ir in rhenium single crystal have been determined to be Qs(184Ir) = + 2.0(3) b MHz and Qs(185Ir) = +2.0(3) b MHz. Adopting the value of -3.6(2)×1017 V·cm-2 for the electric field gradient eq at T=0 K, the values of the ground-state spectroscopic quadrupole moments of these isotopes are determined to be Qs(184Ir)=+2.0(3) b and Qs(185Ir)=-2.5(3) b. The185Ir moment is only consistent with the ground state Nilsson configuration $$I^\pi K = \tfrac{5}{2} - \tfrac{1}{2}$$ , the184Ir moment is consistent with K=4 with a predominant K=4 component, in disagreement with K=0,1 found for186Ir. Our analysis differs in detail from the recent nuclear orientation study by Hagn et al.[1].

The quadrupole frequenciese2qQ/h, for186, 188–190Ir in a Re single crystal have been determined by nuclear orientation at temperatures down to 2 mK. Using a modeldependent value of +1.0 b for the quadrupole moment of the ground state of189Ir, the electric field gradient of IrRe at 0 K is found to be-3.6×1017 V·cm-2. The value is consistent with systematics proposed by Raghavan et al. Using this EFG, quadrupole moments are deduced for186, 188, 190Ir.

Nuclear orientation and NMR/ON of114mIn implanted into Fe at an energy of 80 keV and dose of 3–5×1014 cm-2 is reported. The zero applied field resonance frequencyv0=203.65(6) MHz is combined with the recently determinedBhf(InFe) of 286.8(3) kG to yield µ(114mIn)=+4.658(14) nm. The nuclear spin-lattice relaxation time for114mIn in iron is measured to be 88(18) s at 18 mK and the applied field dependence of the NMR/ON resonance frequency gives the Knight shift for the system as -2.4(6)%. The absence of measurable nuclear orientation in similarly prepared114mInCo sources is discussed.