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The first meeting of the CIFAR Fungal Kingdom: Threats & Opportunities research program saw the congregation of experts on fungal biology to address the most pressing threats fungi pose to global health, agriculture, and biodiversity. This report covers the research discussed during the meeting and the advancements made toward mitigating the devastating impact of fungi on plants, animals, and humans.

Display Omitted We introduce a semantic delta methodology for analyzing change in SNOMED CT.Two change analysis techniques are combined into one comprehensive methodology.Changes to sets of concepts are summarized and visualized.Changes in SNOMED CT's Bacterial infectious disease subhierarchy are analyzed. Thousands of changes are applied to SNOMED CTs concepts during each release cycle. These changes are the result of efforts to improve or expand the coverage of health domains in the terminology. Understanding which concepts changed, how they changed, and the overall impact of a set of changes is important for editors and end users. Each SNOMED CT release comes with delta files, which identify all of the individual additions and removals of concepts and relationships. These files typically contain tens of thousands of individual entries, overwhelming users. They also do not identify the editorial processes that were applied to individual concepts and they do not capture the overall impact of a set of changes on a subhierarchy of concepts.In this paper we introduce a methodology and accompanying software tool called a SNOMED CT Visual Semantic Delta (semantic delta for short) to enable a comprehensive review of changes in SNOMED CT. The semantic delta displays a graphical list of editing operations that provides semantics and context to the additions and removals in the delta files. However, there may still be thousands of editing operations applied to a set of concepts. To address this issue, a semantic delta includes a visual summary of changes that affected sets of structurally and semantically similar concepts. The software tool for creating semantic deltas offers views of various granularities, allowing a user to control how much change information they view. In this tool a user can select a set of structurally and semantically similar concepts and review the editing operations that affected their modeling. The semantic delta methodology is demonstrated on SNOMED CTs Bacterial infectious disease subhierarchy, which has undergone a significant remodeling effort over the last two years.

Objective: Quality assurance of large ontological systems such as SNOMED CT is an indispensable part of the terminology management lifecycle. We introduce a hybrid structural-lexical method for scalable and systematic discovery of missing hierarchical relations and concepts in SNOMED CT. Material and Methods: All non-lattice subgraphs (the structural part) in SNOMED CT are exhaustively extracted using a scalable MapReduce algorithm. Four lexical patterns (the lexical part) are identified among the extracted non-lattice subgraphs. Non-lattice subgraphs exhibiting such lexical patterns are often indicative of missing hierarchical relations or concepts. Each lexical pattern is associated with a potential specific type of error. Results: Applying the structural-lexical method to SNOMED CT (September 2015 US edition), we found 6801 non-lattice subgraphs that matched these lexical patterns, of which 2046 were amenable to visual inspection. We evaluated a random sample of 100 small subgraphs, of which 59 were reviewed in detail by domain experts. All the subgraphs reviewed contained errors confirmed by the experts. The most frequent type of error was missing is-a relations due to incomplete or inconsistent modeling of the concepts. Conclusions: Our hybrid structural-lexical method is innovative and proved effective not only in detecting errors in SNOMED CT, but also in suggesting remediation for these errors.

A miniaturized antipodal Vivaldi antenna to operate from 1 to 30 GHz is designed for nondestructive testing and evaluation of construction materials, such as concrete, polymers, and dielectric composites. A step-by-step procedure has been employed to design and optimize performance of the proposed antenna. First, a conventional antipodal Vivaldi antenna (CAVA) is designed as a reference. Second, the CAVA is shortened to have a small size of the CAVA. Third, to extend the low end of frequency band, the inner edges of the top and bottom radiators of the shortened CAVA have been bent. To enhance gain at lower frequencies, regular slit edge technique is employed. Finally, a half elliptical-shaped dielectric lens as an extension of the antenna substrate is added to the antenna to feature high gain and front-to-back ratio. A prototype of the antenna is employed as a part of the microwave imaging system to detect voids inside concrete specimen. High-range resolution images of voids are achieved by applying synthetic aperture radar algorithm.

A small antipodal Vivaldi antenna with rectangular slits at sun-shaped configuration and a half elliptical-shaped dielectric lens is designed for microwave and millimeter-wave imaging applications. The slits are developed to extend low end of frequency band and increase antenna gain at lower frequencies, while the lens is applied to this antenna to feature high gain at higher frequencies, high front-to-back ratio, low sidelobe and cross-polarization levels, narrow half-power beamwidth, and modification on E-plane tilt of beam. A prototype of the antenna with small size of 30 × 55 × 0.508 mm3 is fabricated and employed as a part of microwave and millimeter-wave imaging system. Applicability of the proposed antenna for 3-D and 2-D images of targets such as rubber discs and metal rods at different depths inside construction materials including foam and plasterboard sheet-layered structures is demonstrated. High-range resolution images are achieved by applying synthetic aperture radar algorithm.

High-quality microwave and millimetre wave imaging of construction materials and structures requires ultra-wideband (UWB) techniques to provide high-range resolution as well as a reasonable penetration depth. A modified compact microwave and millimetre wave UWB antipodal Vivaldi antenna is designed and presented in this study. First, the conventional antipodal Vivaldi antenna is designed as a reference antenna. Then, to provide the desired frequency range (3.4-40 GHz) with increased gain at its lower frequencies, the slit edge technique is applied, thus creating a periodic slit edge antipodal Vivaldi antenna (PSEAVA). Finally, a trapezoid-shaped dielectric lens (TDL) as an extension of the substrate is added and optimised to increase gain and directivity at higher frequencies of the frequency range, creating PSEAVA with a TDL (PSEAVA-TDL). The results show that the PSEAVA-TDL has the highest gain (up to 16 dB) and front-to-back ratio (up to 37.5 dB), and the narrowest half power beamwidth (down to 11.7°). A prototype of the proposed PSEAVA-TDL with compact size of 40 × 90 × 0.508 mm 3 is fabricated and applied for the imaging of samples made of construction materials. High-range resolution images of the samples are obtained with this antenna by using synthetic aperture radar algorithm.

An ultra-wideband elliptically tapered antipodal Vivaldi antenna designed for civil engineering applications is presented. It is based on design of a conventional antipodal Vivaldi antenna (CAVA) which impedance bandwidth is limited at low end of frequency band. To extend impedance bandwidth, inner edges of top and bottom radiators of the CAVA have been properly bent; however, its gain and front-to-back (F-to-B) ratio is low at the low frequencies. To enhance gain and F-to-B ratio, the comb-shaped slits on edges of the radiators of CAVA are applied. The obtained results exhibit the impedance bandwidth of 1.65-18 GHz, gain of 6.7 dB at 1.65 GHz, and F-to-B ratio of 42 dB at 13.5 GHz that are higher than those parameters of the CAVA. Applicability of the proposed antenna for detection of void inside concrete beam is demonstrated. First, models of the proposed antenna and concrete beam possessing void are created in computer simulation technology and numerical study is performed. Then, a prototype of the antenna is fabricated and employed as part of microwave imaging system to verify simulation results and to detect voids inside concrete beam.

Nondestructive evaluation of stratified (layered) composite structures at microwave and millimeter-wave frequencies is of great interest in many applications where simultaneous determination of the complex dielectric properties and thicknesses of multiple layers is desired. Open-ended rectangular waveguide probes, radiating into such structures, are effective tools for this purpose. The technique utilizes a full-wave electromagnetic model that accurately models the complex reflection coefficient as a function of frequency and material properties. While the electromagnetic model assumes an infinite waveguide flange (or ground plane), the measurements are conducted using a finite-sized flange. Consequently, the results of the electromagnetic model and those from measurements may not be sufficiently alike for accurate dielectric property and thickness evaluation. This paper investigates the effect of using an open-ended waveguide with a standard finite-sized flange on the error in evaluating the complex dielectric properties of a composite structure. Additionally, we present the design of a novel flange that markedly reduces this undesired effect by producing very similar electric field properties, at the flange aperture, to those created by an infinite flange. Finally, the efficacy of the design for evaluating the dielectric properties of a layered composite structure is demonstrated as well.

Recent technological advancements have made it possible to produce synthetic aperture radar (SAR) based microwave images in real time by using a variety of microwave imaging (array) systems. However, depending on the imaging array construction and the data collection scheme, the pertinent data of interest may be corrupted by undesired signals resulting from array element mutual coupling and overall poor isolation. Poor isolation associated with array elements may result from imperfect RF switching, internal coupling mechanisms inherent in a measurement system, or imperfect signal tagging schemes (i.e., multiple elements modulating when using the modulated scatterer technique). Images produced from such corrupted data are blurred or have artifacts that tend to mask the desired indications. This paper demonstrates the extension of a well-known correlation canceling technique for the purpose of preprocessing the data to remove such undesired coupling effects. To demonstrate its effectiveness, it is applied to a recently developed 2-D high-resolution and real-time microwave imaging system (camera). This camera is composed of 576 array elements, which are susceptible to the type of signal degradation mentioned above. Three correction estimates of the preprocessor are performed and compared. Two of the correction estimates directly address coupling, and the third, which does not consider coupling, is used for comparison purposes. Simulation results show the efficacy of this method, which is then corroborated by experiments.

A new compressed sensing (CS) image reconstruction method is proposed for high-resolution wideband threedimensional synthetic aperture radar (SAR) imaging systems. In contrast to existing CS SAR methods that employ only a forward SAR transform in pre- or post-processing, the proposed method employs both forward SAR and reverse SAR (R-SAR) transforms in each CS iteration to improve the quality of reconstructed images. This study proposes a simple and elegant truncation repair method to combat the truncation error and utilises non-uniform fast Fourier transform to reduce the SAR and R-SAR transform errors, thereby ensuring the convergence of the CS algorithm and improving the quality of the reconstructed images. The proposed CS SAR method is applied to microwave and millimeter wave imaging systems for non-destructive evaluation of materials embedded in stratified media. Three different specimens under test are measured by conventional uniform sampling and by random under-sampling with 20% or 30% spatial points of the uniform sampling. The reconstructed images show that, albeit having much less measurement points, the proposed CS method achieves better image quality and lower background artefacts than the images reconstructed from the fullysampled uniform measurements.

Wideband synthetic aperture radar (SAR) technique is a robust imaging tool for microwave and millimeter-wave imaging such as nondestructive evaluation applications. In this paper, we present an alternative method to conventional raster scanning involving manually selected and nonuniformly distributed measurement positions, enabling the production of complete SAR images—potentially using only a fraction of the conventionally required measured data. The user is kept informed throughout the scanning process by a stream of real-time SAR images. Finally, data reconstruction algorithms are used offline to produce high-quality images with considerably lower background noise and image artifacts as compared to the real-time images. We also introduce a novel reconstruction method that uses the components of the SAR algorithm to advantageously exploit the inherent spatial information contained in the data, resulting in a superior data reconstruction and final SAR image. This paper presents the measurement methodology along with the images obtained from three different specimens of increasing geometrical complexity.

Microwave and millimeter-wave synthetic aperture radar (SAR)-based imaging techniques, which are used for nondestructive evaluation (NDE), have shown tremendous usefulness for the inspection of a wide variety of complex composite materials and structures. An important practical issue associated with these imaging techniques is the required criteria associated with the physical gathering of the imaging data. In previous work on uniform sampling optimization, it was shown that the (uniform) spatial sampling density should be higher than the Nyquist density if preservation of spatial resolution, as defined by the half-power width of an ideal point target, is of interest. Conversely, nonuniform sampling has shown to provide effective signal reconstruction even for average spatial sampling densities below the Nyquist density-a distinct advantage over uniform sampling. This paper presents a comprehensive study into the optimization of nonuniform sampling for microwave SAR-based NDE imaging using three typical reconstruction techniques for nonuniformly sampled data, including natural interpolation, area-weighted Fourier integration, and conjugate gradient residual error minimization methods. To study the efficacy of these reconstruction methods, simulations of a point target were performed for a range of target distances and a range of average spatial sample separations. Resulting SAR images from the reconstruction techniques are then analyzed and compared according to two metrics: error between an image and an ideal image and resolution as determined by the half-power width of a point target. This is followed by experimental results corroborating the simulation results. Finally, nonuniform sampling requirements, given a minimum metric performance, are generalized for a given imager aperture size.

Objective—To determine major causes of death and the anatomic location of musculoskeletal injuries in Quarter Horse racehorses in California. Design—Retrospective case series. Animals—314 Quarter Horse racehorses with musculoskeletal injuries that were necropsied through the California Horse Racing Board Postmortem Program from 1990 to 2007. Procedures—Postmortem pathology reports were retrospectively reviewed. Musculoskeletal injuries were categorized by anatomic region and described. The number of Quarter Horse starts and starters for the same period of time were obtained from a commercial database for determination of fatal injury incidence. Results—Musculoskeletal injuries accounted for 314 of the 443 (71 %) Quarter Horse racehorses that died during the 18-year study period. Fatal musculoskeletal injuries occurred at a rate of 2.0 deaths/1,000 race starts and 18.6 deaths/1,000 horses that started a race. Musculoskeletal injuries occurred predominantly during racing (84%) and in the forelimbs (81%). The most common fatal musculoskeletal injuries were metacarpophalangeal and metatarsophalangeal joint (fetlock) support injuries (40%) and carpal (24%), vertebral (10%), and scapular (8%) fractures. Proximal interphalangeal (pastern) joint luxations resulted in death of 3% of horses. Fracture configurations of some bones were consistent with those of Thoroughbred racehorses. Evidence of preexisting stress remodeling of bone was reported for some fractures. Conclusions and Clinical Relevance—Knowledge of common locations and types of fatal musculoskeletal injuries in racing Quarter Horses may enhance practitioners' ability to detect mild injuries early, rest horses, and help prevent catastrophic injuries.

A NASA effort is underway to develop a nondestructive inspection method to evaluate the bonding condition for heat shield blocks that are bonded to a composite substrate. The initial effort is reported in this paper. The goal is to demonstrate a proof of concept for a reliable detection method using a single-sided scan capability applied from the outside of the heat shield blocks. Two representative samples with known defects are made available for the initial proof of concept; the results of one sample are reported here. The two specimens had been scanned using various nondestructive testing methods including immersion ultrasound, handheld ultrasound, air-coupled ultrasound, microwave, Terahertz, computed radiography, and shearography. These efforts were performed by industry experts and academia. All were limited in their detectability of the known flawed regions in the specimens and suffered high levels of uncertainty in the good regions. Most nondestructive evaluation methods are sensitive to detecting changes in the material property. This means that an air pocket is easy to detect in an unbounded interface but when the air pocket is absent and the two surfaces are in intimate contact (kissing bond) most methods fails to detect the difference. Electromagnetic methods (radiography, thermography, microwave, Terahertz) will not detect a change in material property. Shearography is not successful in attempting to detect changes in stiffness through the highly damping thick heat shield layer. As a mechanical wave, ultrasound is the primary method that may be able to detect a kissing bond. However, it was quickly recognized that ultrasound has to overcome a number of difficult challenges related to the nonhomogeneous and highly damping nature of the thermal shield material. Inhomogeneity causes pronounced changes in signal strength that make the distinction between good and bad areas very difficult. At the same time, scatter and attenuation become detrimental to high frequency ultrasonic signals, which are necessary to resolve echoes returning from the bond line. Conversely, low frequency sound waves provide poor spatial and temporal resolution due to the broader wavelengths associated with the signal.

Microwave imaging systems for nondestructive evaluation, based on 3-D synthetic aperture radar (SAR) techniques, utilize either a real aperture, composed of many antennas mounted next to one another, or a synthetic aperture, generated by raster scanning a single antenna. To obtain a quality SAR image, the spatial sampling must be dense enough to accurately sample the electric field reflected from a target. Conversely, the quantity of spatial samples may be optimally reduced, resulting in reduced system complexity and required resources for systems employing real apertures and reduced imaging time for synthetic aperture systems. In the literature, it has been reported that the optimum sampling step size is equal to the theoretical resolution, as per the Nyquist rate. It has also been reported that an image generated using a sampling step size equal to the theoretical resolution may not possess the same spatial resolution as predicted. Also, as expected and reported, resolution is dependent upon the distance between the target and the aperture, aperture dimensions, and antenna beamwidth. However, existing formulations of SAR resolution do not account for all of the physical characteristics of a measurement (e.g., 2-D limited-size aperture, electric field decreasing with distance from the measuring antenna, etc.). This paper presents a theoretical formulation of resolution and a study into optimum uniform spatial sampling by analyzing simulated 3-D SAR images according to metrics representing image quality, namely, half-power resolution and RMS error between practically sampled images and an ideally sampled image. The results of this simulation demonstrate optimum sampling given design requirements that fully explain resolution dependence on sampling step size. Also, it is found that there is additional widening of the 2-D spectral estimation of the data due to the aperture-limited nature of the measurements, which further influences the choice of sampling step size. Subsequently, the simulated results are compared to experimental results corroborating the efficacy of the formulation. Finally, design curves and procedures are proposed for selecting sampling step size as per resolution requirements.

Summary Reasons for performing study: To determine if scapular fractures occur in racehorses with distinctive characteristics. Objectives: To test the hypothesis that Thoroughbred (TB) and Quarter Horse (QH) racehorses with a scapular fracture have similar characteristics that are different from those of their respective racetrack populations. Methods: Necropsy findings, case details, last race information and career earnings for TB and QH racehorses that had a scapular fracture in California between 1990 and 2008 were retrospectively compared between breeds. Horse signalment, career earnings, career starts and race characteristics were obtained for all California racehorses. Comparisons were made between affected horses, other racehorses that died, and all horses that raced, in California during the 19 year period. Results: Seventy-three TB and 28 QH racehorses had a similar, complete comminuted scapular fracture with an articular component, and right forelimb predilection. The QHs had a higher incidence of scapular fracture incurred during racing than TBs (0.98 vs. 0.39/1000 starters). The TB and QH incident rates for musculoskeletal deaths incurred racing were 20.5 and 17.5/1000 starters, respectively; however, a greater proportion of TB musculoskeletal deaths occurred training (40% vs. 8%). Horses with a scapular fracture were more likely to be male and aged 2 or ≥5 years than the racetrack population. Most affected QHs (64%) were 2-year-olds; most TBs (74%) were aged ≥3 years. Scapular fractures occurred more commonly during racing in QHs (70%) than TBs (44%). Race-related scapular fracture was more likely to occur in a Maiden race than in a non-Maiden race. Horses with a scapular fracture had fewer career starts than the racetrack population. Conclusions and potential relevance: Despite breed differences for signalment and exercise distances, both breeds incur a complete scapular fracture that is more likely to occur in the right scapula of young and older, male racehorses, early in their race career or after few races. Quarter Horses sustain a catastrophic scapular fracture more frequently than TBs.

Millimeter-wave imaging techniques, based on synthetic aperture focusing (SAF), have been successfully used for nondestructive testing (NDT) of various composite and aerospace structures. Most current imaging mechanisms utilize raster scanning platforms, whereby the imaging system is scanned in a rectangular grid over the structure-under-test (SUT). Most raster scanning platforms, although relatively simple in design and construction, are inherently slow. Furthermore, SAF techniques necessitates the use of vector-measuring instruments such as a vector network analyzer (VNA), which are typically: 1) bulky; 2) cannot be mounted on scanning platforms; 3) are not suitable for in-field use; and 4) expensive. These factors limit the effectiveness of these millimeter-wave imaging techniques in applications where frequent and rapid inspection of large structures is required. Hence, there is a great demand for rapid mechanical scanning systems combined with portable wideband transceivers in order to increase the utility of these imaging techniques, and provide a real solution to many practical NDT applications. To this end, a unique rotary scanner system, capable of scanning a relatively large area in a relatively short span of time, was designed and constructed. In addition, a custom-designed portable transceiver system operating in the frequency range of 35-45 GHz (Q-band) was developed and incorporated into the rotary scanner system for producing coherent (amplitude and phase) and accurate data suitable for synthetic aperture imaging and the 10-GHz bandwidth allows the generation of relatively high-resolution millimeter-wave holographical images. This paper presents the design of the rotary scanning system, the associated Q-band transceiver and the integration of the two systems via a custom-designed software. To illustrate the efficacy of the complete imaging system, SAF of several complex structures produced using the proposed system, are presented and discussed.

Recently, a real-time and portable 2-D microwave imaging system operating at 24 GHz, incorporating modulation schemes similar to modulated scatterer technique and synthetic aperture radar (SAR) imaging technique, was designed using a heterodyne receiver with superior performance compared with a homodyne receiver. Multifrequency SAR images have the added advantage of providing for: 1) coherent averaging of image data over frequency and hence increasing system signal-to-noise ratio (SNR) and 2) enable volumetric (3-D) image production. This letter describes modifications to this receiver for enabling multifrequency operation through phase uncertainty (PU) analysis. These modifications show significant reduction in PU, thereby allowing the coherent addition of data necessary for SAR image formation with higher overall SNR.

Summary Reasons for performing study: To improve the understanding of exercise related sudden death in Thoroughbred racehorses. Objectives: To describe the post mortem findings in cases of sudden death associated with exercise in 268 Thoroughbred racehorses. Methods: Gross and histological post mortem findings of 268 cases of sudden death were collated and reviewed. Cases originated from 6 racing jurisdictions around the world. Sudden death was defined as acute collapse and death in a closely observed and previously apparently healthy Thoroughbred racehorse, during, or within one hour after, exercise. Cause of death as determined by the attending pathologist was categorised as definitive, presumptive or unexplained and compared between the different populations. Cardiopulmonary lesions recorded at post mortem examination were compared between different populations. Results: Pathologists recorded a definitive cause of death in 53% (143/268) of cases. Major definitive causes of sudden death included cardiac failure, apparent pulmonary failure, pulmonary haemorrhage, haemorrhage associated with pelvic fractures or with idiopathic blood vessel rupture, and spinal cord injury. A presumptive cause of death was made in 25% (67/268) of cases and death remained unexplained in 22% (58/268) of cases. There were several statistically significant inter-population differences in the cause of death and in reporting of cardiopulmonary lesions. Conclusions: Sudden death can be attributed to a variety of causes. Causes of sudden death and the lesions found in cases of exercise-related sudden death are similar in different racing jurisdictions. However, the lesions are often not specific for the cause of death and determination of the cause of death is therefore affected by interpretation by the individual pathologist.

Summary Myelogenous leukemia was diagnosed in a 4-year old female cat. The onset of clinical illness was sudden, and clinical signs present were weakness, splenomegaly, lymphadenopathy, and pale mucous membranes. Hematologic examination revealed anemia, leukocytosis and many immature granulocytes in the peripheral blood. Splenomegaly, hepatomegaly, lymphadenopathy and increased amount of red bone marrow were the principal lesions seen post mortem. Microscopic examination of tissue sections revealed masses of tumor cells in the liver, spleen, lymph nodes, bone marrow, kidney and adrenal. The true myelogenous origin of the tumor cells was determined by peroxidase staining of blood, bone marrow and tissue impression smears. Zusammenfassung Ein Fall von myelonischer Leukose bei der Katze Bei einer 4jahrigen Katze wurde eine myeloische Leukose diagnostiziert. Die Krankheit setzte plotzlich ein. Klinisch wurden folgende Symptome festgestellt: Allgemeine Schwache, Splenomegalie, Lymphadenopathie, blasse Schleimhaute. Hamatologie: Anamie, Leukozytose, viele unreife Granulozyten im peripheren Blut. Sektionsbefund: Splenomegalie, Hepatomegalie, Lymphadenopathie, Vermehrung des roten Knochenmarkes. Histologie: Tumorzellen in Leber, Milz, Lymphknoten, Knochenmark, Niere und Nebenniere. Der myeloische Ursprung der Tumorzellen wurde durch die Peroxydase-Reaktion der Zellen aus dem Blut, dem Knochenmark und andern Geweben erhartet. Resume Un cas de leucemie myelogene chez le chat On diagnostique une leucemie myelogene chez un chat femelle âge de 4 ans. Les signes cliniques de la maladie se sont declares brusquement, avec des symptomes de faiblesse, splenomegalie, lymphadenopathie et muqueuses pâles. L'examen hematologique revele une anemie, une leucocytose et de nombreux granulocytes immatures dans le sang peripherique. Les principales lesion observees post mortem sont une splenomegalie, hepatomegalie, lymphadenopathie et une quantite accrue de moelle osseuse rouge. Un examen microscopique des coupes de tissus revele une multitude de cellules tumorales dans le foie, le rate, les ganglions lymphatiques, la moelle osseuse, les reins et les surrenales. On determine l'origine myelogene reelle des ces cellules tumorales par une coloration peroxydasique du sang et de la moelle osseuse et par des decalques de tissus. Resumen Un caso de leucemia mielogena en el gato En una gata, de 4 anos de edad, se diagnostico leucemia mielogena. La aparicion de la enfermedad clinica fue repentina, y los sintomas clinicos presentes eran adelgazamiento, esplenomegalia, linfadenopatia y membranas mucosas palidas. El examen hematologico revelo anemia, leucocitosis y muchos granulocitos inmaduros en la sangre periferica. Las lesiones principales observadas en la autopsia fueron: esplenomegalia, hepatomegalia, linfadenopatia y aumento de la cantidad de medula osea roja. El examen microscopico de cortes histologicos evidencio masas de celulas tumorales en el higado, bazo, ganglios linfaticos, medula osea, rinon y glandula anterrenal. El origen mielogeno verdadero de las celulas tumorales se confirmo mediante la coloracion peroxidasica de la sangre, medula osea y extensiones de impresion histica.

The Air and space Operations Center (AOC), also deployed as Joint (JAOC) or Combined (CAOC), is the United States Air Force's (USAF's) weapon system for planning and executing theater-wide air and space forces. Like any USAF weapon system, trainers and warfighters need to assess AOC performance on a continual basis. Currently, no automated methods or tools exist to assess this performance. To address this need, a prototype assessment capability, the CAOC Performance Assessment System (CPAS) was developed. Working with and observing subject matter experts allowed engineers to identify the information required to support dynamic targeting training and assessment. Using rapid-prototyping spiral development, a “non-intrusive” data capture (collection and archiving) capability and an informative user display were developed and demonstrated. Specifically, CPAS collects AOC process data, correlates AOC data sources, and displays events and decisions that occur within the dynamic targeting cell of the AOC to support post-mission assessment of AOC process performance. It has been in use by the Air Force for over two years.

Micro Computed Tomography (micro-CT) of cores is an emerging technology that yields vital information about key rock and fluid properties at pore-scale resolution. Micro-CT imaging results presented to date are encouraging and indicate that this technology has the potential to revolutionize petrophysical analysis and reservoir engineering. The application of micro-CT in petroleum engineering requires reconstructed scan data to be of high and uniform image quality to enable reliable analysis during subsequent segmentation and numerical modeling. This is achievable in existing micro-CT systems using standard circular scan trajectories with non-exact filtered backprojection (FBP) reconstruction, but requires small cone angles to keep cone beam artifacts below detectable limits. We describe the implementation and results of adapting an exact helical FBP reconstruction algorithm (the so-called “Katsevich Algorithm” or KFBP) and data acquisition scheme on a high-performance micro-CT system normally running in circular scan trajectory mode. Side-by-side comparisons of stitched circular scan trajectories with continuous helical scan trajectories on simulated and real rock core data show the throughput advantage of this modality for applications relevant for the petroleum industry keeping equivalent image quality to low cone angle circular scans. The analytical exact helical reconstruction can be performed in quasi-real time leading to instantaneous results. Simulated and experimental results indicate that an imaging throughput improvement of 2-5 times can be achieved employing KFBP-based exact helical reconstruction compared to the standard circle scan trajectory when imaging whole rock cores/plugs that are significantly longer than their diameter.

Objective Standards terminologies may be large and complex, making their quality assurance challenging. Some terminology quality assurance (TQA) methodologies are based on abstraction networks (AbNs), compact terminology summaries. We have tested AbNs and the performance of related TQA methodologies on small terminology hierarchies. However, some standards terminologies, for example, SNOMED, are composed of very large hierarchies. Scaling AbN TQA techniques to such hierarchies poses a significant challenge. We present a scalable subject-based approach for AbN TQA. Methods An innovative technique is presented for scaling TQA by creating a new kind of subject-based AbN called a subtaxonomy for large hierarchies. New hypotheses about concentrations of erroneous concepts within the AbN are introduced to guide scalable TQA. Results We test the TQA methodology for a subject-based subtaxonomy for the Bleeding subhierarchy in SNOMED's large Clinical finding hierarchy. To test the error concentration hypotheses, three domain experts reviewed a sample of 300 concepts. A consensus-based evaluation identified 87 erroneous concepts. The subtaxonomy-based TQA methodology was shown to uncover statistically significantly more erroneous concepts when compared to a control sample. Discussion The scalability of TQA methodologies is a challenge for large standards systems like SNOMED. We demonstrated innovative subject-based TQA techniques by identifying groups of concepts with a higher likelihood of having errors within the subtaxonomy. Scalability is achieved by reviewing a large hierarchy by subject. Conclusions An innovative methodology for scaling the derivation of AbNs and a TQA methodology was shown to perform successfully for the largest hierarchy of SNOMED.

Socioeconomic status (SES) impacts educational opportunities and outcomes which explains, in part, why the majority of medical students come from the upper two quintiles of family income. A two-factor SES indicator based on parental education (E) and occupation (O) has recently been established by the Association of American Medical Colleges (AAMC). This study validates this two-factor indicator as applicable to the national pool of medical school applicants.The AAMC SES EO indicator classifies applicants into five ordered groups (EO-1 through EO-5) based on four aggregated categories of parental education and two aggregated categories of occupation. The EO indicator was applied to the 2012 American Medical College Application Service applicant pool. The authors examined the associations that the EO category had with six additional and independent indicators of socioeconomic (dis)advantage, as well as with demographic and educational characteristics and life experiences.The EO indicator could be applied to 89% of the 2012 applicants. The lower the EO category, the stronger the association with each of the six indicators of socioeconomic disadvantage. Other notable, but weaker, associations with the EO indicator were differences by age, race/ethnicity, performance on the Medical College Admission Test, community college attendance, and certain self-reported life experiences.The EO indicator provides a simple, intuitive, widely applicable, and valid means for identifying applicants from socioeconomically disadvantaged backgrounds. This affords admissions committees an additional factor to consider during the holistic review of applicants in order to further diversify the medical school class.

The os acromiale is an accessory bone resulting from failure of the acromial apophysis to fuse to the scapula. It is a relatively frequent defect affecting 4-18% of most large skeletal series. The etiology of os acromiale is poorly understood, and two competing hypotheses have been proposed: (1) that the accessory bone represents a genetic defect, and (2) that it results from mechanical stress on the developing acromion. In order to assess the evidence for these two hypotheses, os acromiale frequencies from a South African cadaver sample (n = 494) were compared to frequencies from a medieval Danish archaeological sample (n = 532). The South African frequency (18.2%) was significantly higher than the medieval Danish frequency (7.7%, p < 0.0001). These results mirror those of another study comparing African- and Euro-Americans, and tend to support the genetic hypothesis. However, a left side bias (72%) was also found among the South Africans (p = 0.013), lending some support to the mechanical stress hypothesis. Sex and age biases were also examined but were not found. In order to further test the mechanical hypothesis, the medieval Danes were divided into groups of higher and lower socioeconomic status based upon cemetery type. Lower status individuals were presumed to have engaged in strenuous labor activities more often and at a younger age than higher status individuals. However, comparison of these two groups failed to demonstrate a significant frequency difference (p = 0.105). Based on the results of this study, it is suggested that a third etiology combining a genetic predisposition for os acromiale with mechanical stress as the proximate cause should also be considered.

Objective Large and complex terminologies, such as Systematized Nomenclature of Medicine–Clinical Terms (SNOMED CT), are prone to errors and inconsistencies. Abstraction networks are compact summarizations of the content and structure of a terminology. Abstraction networks have been shown to support terminology quality assurance. In this paper, we introduce an abstraction network derivation methodology which can be applied to SNOMED CT target hierarchies whose classes are defined using only hierarchical relationships (ie, without attribute relationships) and similar description-logic-based terminologies. Methods We introduce the tribal abstraction network (TAN), based on the notion of a tribe—a subhierarchy rooted at a child of a hierarchy root, assuming only the existence of concepts with multiple parents. The TAN summarizes a hierarchy that does not have attribute relationships using sets of concepts, called tribal units that belong to exactly the same multiple tribes. Tribal units are further divided into refined tribal units which contain closely related concepts. A quality assurance methodology that utilizes TAN summarizations is introduced. Results A TAN is derived for the Observable entity hierarchy of SNOMED CT, summarizing its content. A TAN-based quality assurance review of the concepts of the hierarchy is performed, and erroneous concepts are shown to appear more frequently in large refined tribal units than in small refined tribal units. Furthermore, more erroneous concepts appear in large refined tribal units of more tribes than of fewer tribes. Conclusions In this paper we introduce the TAN for summarizing SNOMED CT target hierarchies. A TAN was derived for the Observable entity hierarchy of SNOMED CT. A quality assurance methodology utilizing the TAN was introduced and demonstrated.

The relatively large number of naviculo-cuneiform I cases reported from Japan, and their rarity in American and European clinical literature, suggests that populations may vary in tarsal coalition frequency [Kumai T, Tanaka Y, Takakura Y, Tamai S. Isolated first naviculocuneiform joint coalition. Foot Ankle Int 1996;17:635–40]. Our objective is to test for significant differences in naviculo-cuneiform I coalition frequency between geographically distinct populations. Skeletal remains from one African sample and two samples of European ancestry were analyzed. Fisher's Exact tests [Uitenbroek DG. Fisher Exact [online]. 2000 [cited 2004 March 10]. Available from: URL: http://home.clara.net/sisa/fisher.htm] were employed to identify sample differences ( α =0.05). Six cases of naviculo-cuneiform I coalition were identified in the African sample; no cases were found in the Danish or American samples. Naviculo-cuneiform I coalition was significantly more prevalent in South African Bantu than in medieval Danes ( p =0.014; 1− β =0.70) or the combined sample of European ancestry ( p =0.003; 1− β =0.83). Given the sample sizes studied, a statistical difference was not found between the American and South African samples ( p =0.087; 1− β =0.52). Population differences in naviculo-cuneiform I coalition are clinically relevant since tarsal coalition may be symptomatic and associated with other abnormalities. Carpal coalition and transposition of the maxillary canine and first premolar were each found to be significantly associated with naviculo-cuneiform I coalition.

Corrosion of steel rebar in a concrete structure compromises its structural integrity and hence its performance. Chloride intrusion into concrete can lead to depassivation of the steel and initiation of corrosion. Methods exist to detect chlorides in concrete, but the practical use of many of these may be problematic because they are destructive and time consuming, and cannot be used to analyze large structures. Microwave nondestructive evaluation techniques applied to mortar have proven successful for detecting mixture constituents, chloride ingress, and cure-state monitoring. In this paper several concrete samples are cyclically soaked in distilled water and saltwater while also experiencing compression force. Compression force, simulating in-service loading, results in increased microcracking and permeability, which promotes chloride ingress. The daily microwave reflection properties of these samples were measured at 3 GHz. The results show the capability of these microwave measurements for detecting the increased level of chloride permeation as a function of increasing number of soaking cycles. In addition, comparisons between the reflection properties of mortar and concrete cubes soaked in distilled water exhibit similarity in trends, indicating that the various phenomena that occur within them are systematically similar.

The Logical Observation Identifier Names and Codes (LOINC®) database provides a universal code system for reporting laboratory and other clinical observations. Its purpose is to identify observations in electronic messages such as Health Level Seven (HL7) observation messages, so that when hospitals, health maintenance organizations, pharmaceutical manufacturers, researchers, and public health departments receive such messages from multiple sources, they can automatically file the results in the right slots of their medical records, research, and/or public health systems. For each observation, the database includes a code (of which 25 000 are laboratory test observations), a long formal name, a “short” 30-character name, and synonyms. The database comes with a mapping program called Regenstrief LOINC Mapping Assistant (RELMATM) to assist the mapping of local test codes to LOINC codes and to facilitate browsing of the LOINC results. Both LOINC and RELMA are available at no cost from http://www.regenstrief.org/loinc/. The LOINC medical database carries records for >30 000 different observations. LOINC codes are being used by large reference laboratories and federal agencies, e.g., the CDC and the Department of Veterans Affairs, and are part of the Health Insurance Portability and Accountability Act (HIPAA) attachment proposal. Internationally, they have been adopted in Switzerland, Hong Kong, Australia, and Canada, and by the German national standards organization, the Deutsches Instituts für Normung. Laboratories should include LOINC codes in their outbound HL7 messages so that clinical and research clients can easily integrate these results into their clinical and research repositories. Laboratories should also encourage instrument vendors to deliver LOINC codes in their instrument outputs and demand LOINC codes in HL7 messages they get from reference laboratories to avoid the need to lump so many referral tests under the “send out lab” code.

Infection with Brucella spp. continues to pose a human health risk in California despite great strides in eradicating the disease from domestic animals. Clustering of human cases in time and space has important public health implications for understanding risk factors and sources of infection. Temporal-spatial clustering of human brucellosis in California for the 20-year period 1973-1992 was evaluated by the Ederer-Myers-Mantel, Moran's I, and population-adjusted Moran's I procedures. Cases were clustered in concentrated agricultural regions in the first 5-year interval (1973-1977). Time-space clustering of human brucellosis cases in California late in the 20-year study period may reflect the distribution of Hispanic populations. Public health programs in California should focus on educating Hispanic populations about the risk of consuming dairy products, such as soft cheeses, made from unpasteurized milk.

Detection of corrosion, under paint and primer, in various metallic structural components, particularly when used in moist and salty environments is an important practical concern. Moreover, nondestructive testing techniques that do not require paint removal are desired. Near-field microwave nondestructive inspection techniques, employing open-ended rectangular waveguide probes, have shown tremendous potential for detecting and evaluating the presence of corrosion under paint in steel substrates. The objective of this investigation has been to investigate the potential of these techniques for detecting corrosion under paint and primer in aluminum substrates. To accomplish this goal, an electromagnetic formulation, simulating detection of corrosion in layered structure using open-ended rectangular waveguide probes, was used to gain an insight into the functionality of measurement parameters such as the frequency of operation and standoff distance. In conjunction with this simulation, the dielectric properties of paint, primer, real and chemically produced aluminum oxide were measured in a wide range of microwave frequencies (2.6–18 GHz). The results showed that the dielectric properties of paint, primer and aluminum oxide are very similar to each other. Subsequently, the theoretical simulation was conducted in a wide frequency band (8.2–40 GHz). The overall result of the simulation effort was that higher frequencies and standoff distances of a few mm are more optimal for detecting thin corrosion layers under paint. Two specially prepared aluminum panels with induced areas of corrosion and surface pitting were produced as well. Using these panels and several phase sensitive measurement systems, experiments were conducted producing 2-D images of various areas of these panels. Images were produced at different standoff distances and at frequencies of 9, 11.725, 24.1, and 33.5 GHz. The overall results of the experimental investigation were extremely promising when detecting the thin regions of corrosion in these panels. This paper presents the approach and results of this investigation.

Standards are one of the most efficient ways to prevent data silos, achieve system interoperability, and promote the value of data. Public health’s growing use of electronic data interchange lends increasing urgency to the need to adopt and promote standards, and to participate in standards development as a fully-engaged partner.

Recently, new technologies have made it possible to produce synthetic aperture radar (SAR) based microwave images in real-time by using different microwave imaging arrays. However, depending on the imaging array construction the data of interest may be corrupted by mutual coupling and poor isolation. SAR images created from this data have an increased level of artifacts. This paper presents a method for correcting or pre-processing the data by using correlation canceling technique and provides an analysis of three different estimates of the correction. Simulation results show the efficacy of this method, which is corroborated by experiment.

Thoroughbred racehorses which suffered a fatal musculoskeletal injury (FMI) while racing or race training at a California racetrack during 9 months of 1991 were studied to determine the importance of intensive, high-speed exercise schedules prior to injury. Seventy-seven horses which sustained an FMI while racing and 45 horses which sustained an FMI while race training were successfully matched by race or timed workout session with one control horse and included in the analyses. Race and timed workout (racing-speed exercise) histories were obtained for the case and control horses. Two-month cumulative, racing-speed cutoff distances were calculated from the control horse sample by two methods. Median racing-speed exercise frequencies and distances of the control horses were used to estimate age-specific (2, 3, 4 and ≥ 5 years), 2-month cumulative, racing-speed distances (Method 1). For the second method, the last race or timed workout for each control horse occurring just prior to, or on the date of injury for the matched case horse was identified. Cumulative racing-speed distances 2 months prior to these exercise events were determined for each control horse and used to estimate median age-specific (2, 3, 4 and ≥ 5 years), 2-month cumulative racing-speed distances (Method 2). The cumulative cutoff distances estimated from both methods were used to classify each matched pair according to the presence or absence of a 2-month cumulative, racing-speed distance which exceeded the age-appropriate cutoff distance (exercise distance cluster) within 6 months prior to injury. Manlel-Haenszel matched-pair odds ratios and 95% confidence limits were calculated separately for the racing and race-training fatal injuries. The relative risk for racing FMI was significantly greater for those horses which ran 2-month, cumulative racing and timed workout distances in excess of the cutoff values determined with Method 1 (relative risk (RR) = 3.0, 95% confidence interval (CI) = 1.2, 7.6) and Method 2 (RR = 7.2, 95% CI = 2.6, 20.6). The relative risk for race-training FMI was significantly greater for those horses which ran 2-month, cumulative racing and timed workout distances in excess of the cutoff values determined with Method 2 (RR = 3.4, 95% CI =1.0, 13.2).

This article discusses the role played by HQ USAF operations research analysts assigned to the Director of Operations planning staff at HQ CENTAF Forward (Riyadh, Saudi Arabia) during operations DESERT SHIELD and DESERT STORM. We describe the development of a prototype system to demonstrate the benefits of in-theater operations analysis, and the tasks associated with developing and maintaining a model of the Iraqi integrated air defense system. The model required the operations analysts to interact closely with theater-level and wing-level mission planners to accurately represent the unfolding operations plan. We describe the techniques and tools used to play out the initial stages of the allied air campaign. We also address (i) the estimation of attrition of Iraqi air defense units and Allied Air, (ii) the analysis of airspace congestion during air refueling operations, and (iii) how a simulation model (EADSIM) was used to help pinpoint the cause of Allied air losses. We conclude with a discussion of the impact of analysis on military decision makers at multiple levels of command, based on personal experience. © 1995 John Wiley & Sons, Inc.1

Wide-band synthetic aperture radar (SAR) technique, capable of producing three-dimensional (3D) volumetric images, is a robust imaging tool for microwave and millimeter wave imaging involving nondestructive evaluation (NDE) applications. Conventionally, a relatively large number of measurement samples are required to image even a small area. Thus, it may take a relatively long time to perform the required scan and obtain an image. There is a significant push in the nondestructive testing community towards real-time imaging, particularly when dealing with large and critical structures (i.e., aircraft, bridges, space vehicles, etc.). Here, a method involving non-uniformly sampled wide-band reflection measurements data is described that enables the production of complete SAR images using only a fraction of the required measured data. The imaging method is based on a fast 3D wide-band SAR algorithm that produces 3D SAR images in real-time. Finally, a reconstruction algorithm is used to post-process the data resulting in high quality images with considerably lower background noise/clutter. This paper presents the measurement methodology along with a few experimentally obtained images.

Measured complex reflection coefficient of a spatially-extended stratified composite structure, using an open-ended waveguide, can be effectively used to extract key material and geometrical characteristics of any given layer. This is accomplished using a combination of an electromagnetic model and corresponding measurement data. Previously, it was shown that one parameter can be extracted if all others are known. However, practically it is desirable to extract as many pieces of information as possible. To this end the model must be "inverted". However, there is no closed-form solution for the inverse problem, given the mathematical complexity of the forward model. Consequently, we introduce a forward-iterative optimization method to simultaneously extract several pieces of information about the structure. This method defines key unknowns and uses an analytical approach to estimate the reflection coefficient by minimizing a cost-function using conjugate gradient descent (CGD) as optimizer. This paper presents this method along with an experimental result. Information such as thickness and dielectric properties of a layer in a stratified structure is shown to be extracted concurrently.

This paper presents and discusses the attributes and results of using wideband microwave 3D SAR-based imaging technique for evaluation of reinforced cement-based structures. The technique was used to detect corrosion and thinning of reinforcing steel bars and its potential was demonstrated through experiments for different bar sizes, depth of rebar locations, and spacing between rebars. The results of a limited and preliminary investigation in which thinning of rebars with and without rust in two mortar samples were obtained at three frequency bands covering the frequency range from 8.2 GHz-26.5 GHz.

Nonuniform random sampling is applied to a wideband 3D synthetic aperture radar (SAR) imaging system to reduce the number of measurement points in both frequency and space domains. Experimental tests were performed on a construction foam specimen using uniformly sampled Q-band frequencies in 35.04 GHz to 44.96 GHz and at a grid of two millimeter step sizes. Using discrete Fourier transform (DFT) or discrete cosine transform (DCT) sparse representations, the 3D images can be reconstructed from 7% random samples of the experimental data achieving comparable quality as the one from original full-set data. This can translate to significant time reduction of measurement from more than one hour to less than 20 minutes.

In this commentary, the authors aim to contextualize the history and rationale for what has become the Association of American Medical Colleges-facilitated criminal background check process for entering medical students. As the process was being considered, many issues with a standardized process were identified. There were concerns that demographic or socioeconomic factors might unfairly burden certain applicants or discourage them from applying to medical school. On the other hand, a unified, national program would minimize cost and enhance quality assurance. The authors discuss these issues. Lessons learned in the first three years of the program are also addressed, including some unexpected and favorable consequences such as the identification of accepted applicants with at-risk behaviors (e.g., substance abuse), who would have otherwise gone undetected. Several challenges remain, including the fact that the criminal background check process creates an enhanced role for prehealth advisors and encourages undergraduate institutions to establish standards and processes relating to professionalism. While this is, no doubt, an evolving program which needs continued oversight and ongoing reevaluation, the authors support the continued advancement of the criminal background check process for entering medical students.

In this paper the performance of two wideband synthetic aperture radar (SAR) imaging methods from incomplete data sets are compared quantitatively and qualitatively. The first approach uses nonuniform fast Fourier transform (NUFFT) SAR to form images from nonuniform spatial and frequency data points. The second approach benefits from the emerging compressed sensing (CS) methodology to recover raw data from undersampled measurements. The results of our experimental tests show that CS has a better performance in terms of error and image contrast while NUFFT SAR has lower computational complexity.

Multi‐layered composite structures manufactured with honeycomb, foam, or balsa wood cores are finding increasing utility in a variety of aerospace, transportation, and infrastructure applications. Due to the low conductivity and inhomogeneity associated with these composites, standard nondestructive testing (NDT) methods are not always capable of inspecting their interior for various defects caused during the manufacturing process or as a result of in‐service loading. On the contrary, microwave and millimeter wave NDT methods are well‐suited for inspecting these structures since signals at these frequencies readily penetrate through these structures and reflect from different interior boundaries revealing the presence of a wide range of defects such as isband, delamination, moisture and oil intrusion, impact damage, etc. Millimeter wave frequency spectrum spans 30 GHz–300 GHz with corresponding wavelengths of 10−1 mm. Due to the inherent short wavelengths at these frequencies, one can produce high spatial...

Multi-layered composite structures manufactured with honeycomb, foam, or balsa wood cores are finding increasing utility in a variety of aerospace, transportation, and infrastructure applications. Due to the low conductivity and inhomogeneity associated with these composites, standard nondestructive testing (NDT) methods are not always capable of inspecting their interior for various defects caused during the manufacturing process or as a result of in-service loading. On the contrary, microwave and millimeter wave NDT methods are well-suited for inspecting these structures since signals at these frequencies readily penetrate through these structures and reflect from different interior boundaries revealing the presence of a wide range of defects such as disbond, delamination, moisture and oil intrusion, impact damage, etc. Millimeter wave frequency spectrum spans 30 GHz - 300 GHz with corresponding wavelengths of 10 - 1 mm. Due to the inherent short wavelengths at these frequencies, one can produce high spatial resolution images of these composites either using real-antenna focused or synthetic-aperture focused methods. In addition, incorporation of swept-frequency in the latter method (i.e., holography) results in high-resolution three-dimensional images. This paper presents the basic steps behind producing such images at millimeter wave frequencies and the results of two honeycomb composite panels are demonstrated at Q-band (33-50 GHz). In addition, these results are compared to previous results using X-ray computed tomography.

The physical cause of Space Shuttle Columbia's catastrophic failure was a breach in its thermal protection system, caused by a piece of external tank insulating foam (SOFI) separating from the external tank and striking the leading edge of the left wing of the orbiter. Consequently, there is an urgent need for a rapid, robust and life-circle oriented nondestructive testing (NDT) technique capable of inspecting the SOFI as well as the orbiter's protective heat tiles and its fuselage prior and subsequent to a launch. Microwave and millimeter wave NDT methods have shown great potential to achieve these goals using real focused reflectometer techniques and synthetic aperture focused techniques. This paper presents recent results of an investigation for the purpose of detecting anomalies such as debonds and corrosion in the structurally complex multi-sectioned protective heat tiles using a real focused 150 GHz (D-band) reflectometer and wide-band millimeter wave holography at 18-26.5 GHz (K-band) and 33-50 GHz (Q-band). The results of these investigations clearly show the utility of millimeter wave NDT methods for detecting such anomalies. Both methods provide a significant amount of information about the nature of an anomaly including size and location.

We describe a compact, narrow-linewidth, etalon-tuned titanium:sapphire laser cavity that is designed for field environmental sensing and is pumped by the second harmonic of a kilohertz Nd:YAG laser. The fundamental tunable range is from 690 to 1100 nm, depending on mirror reflectivities and the optics kit used. The conversion efficiency is at least 25% for the fundamental and 2-3% for intracavity frequency doubling from 3.5 to 4 W 532 nm pump power. The linewidth is