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Studies of the effects of volcanic activity on the Hawaiian Islands are extremely relevant due to the past and current co-eruptions at both Mauna Loa and Kilauea. The Big Island of Hawai'i is one of the most seismically monitored volcanic systems in the world, and recent investigations of the Big Island suggest a widespread subsurface connectivity between volcanoes. Volcanic activity has the potential to add mineral contaminants into groundwater ecosystems, thus affecting water quality, and making inhabitants of volcanic islands particularly vulnerable due to dependence on groundwater aquifers. As part of an interdisciplinary study on groundwater aquifers in Kona, Hawai'i, over 40 groundwater wells were sampled quarterly from August 2017 through March 2019, before and after the destructive eruption of the Kilauea East Rift Zone in May 2018. Sample sites occurred at great distance (~80 km) from Kilauea, allowing us to pose questions of how volcanic groundwater aquifers might be influenced by volcanic subsurface activity. Approximately 400 water samples were analyzed and temporally split by pre-eruption and post-eruption for biogeochemical analysis. While most geochemical constituents did not differ across quarterly sampling, microbial communities varied temporally (pre- and post-eruption). When a salinity threshold amongst samples was set, the greatest microbial community differences were observed in the freshest groundwater samples. Differential analysis indicated bacterial families with sulfur (S) metabolisms (sulfate reducers, sulfide oxidation, and disproportionation of S-intermediates) were enriched post-eruption. The diversity in S-cyclers without a corresponding change in sulfate geochemistry suggests cryptic cycling may occur in groundwater aquifers as a result of distant volcanic subsurface activity. Microbial communities, including taxa that cycle S, may be superior tracers to changes in groundwater quality, especially from direct inputs of subsurface volcanic activity.

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Resource-constrained island populations have thrived in Hawai'i for over a millennium, but now face aggressive new challenges to fundamental resources, including the security and sustainability of water resources. Characterizing the microbial community in groundwater ecosystems is a powerful approach to infer changes from human impacts due to land management in hydrogeological complex aquifers. In this study, we investigate how geology and land management influence geochemistry, microbial diversity and metabolic functions. We sampled a total of 19 wells over 2-years across the Hualalai watershed of Kona, Hawai'i analyzing geochemistry, and microbial communities by 16S rRNA amplicon sequencing. Geochemical analysis revealed significantly higher sulfate along the northwest volcanic rift zone, and high nitrogen (N) correlated with high on-site sewage disposal systems (OSDS) density. A total of 12,973 Amplicon Sequence Variants (ASV) were identified in 220 samples, including 865 ASVs classified as putative N and sulfur (S) cyclers. The N and S cyclers were dominated by a putative S-oxidizer coupled to complete denitrification (Acinetobacter), significantly enriched up to 4-times comparatively amongst samples grouped by geochemistry. The significant presence of Acinetobacter infers the bioremediation potential of volcanic groundwater for microbial-driven coupled S-oxidation and denitrification providing an ecosystem service for island populations dependent upon groundwater aquifers.

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The evolution of novel functional traits can contribute substantially to the diversification of lineages. Older functional traits might show greater variation than more recently evolved novelties, due to the accrual of evolutionary changes through time. However, functional complexity and many-to-one mapping of structure to function could complicate such expectations. In this context, we compared kinematics and performance across juveniles from multiple species for two styles of waterfall-climbing that are novel to gobiid fishes: ancestral "powerburst" climbing, and more recently evolved "inching", which has been confirmed only among species of a single genus that is nested within the clade of powerburst climbers. Similar net climbing speeds across inching species seem, at first, to indicate that this more recently evolved mode of climbing exhibits less functional diversity. However, these similar net speeds arise through different pathways: Sicyopterus stimpsoni from Hawai'i move more slowly than S. lagocephalus from La Réunion, but may also spend more time moving. The production of similar performance between multiple functional pathways reflects a situation that resembles the phenomenon of many-to-one mapping of structure to function. Such similarity has the potential to mask appropriate interpretations of relative functional diversity between lineages, unless the mechanisms underlying performance are explored. More specifically, similarity in net performance between "powerburst" and "inching" styles indicates that selection on climbing performance was likely a limited factor in promoting the evolution of inching as a new mode of climbing. In this context, other processes (e.g., exaptation) might be implicated in the origin of this functional novelty.

FRENCH: Diversité fonctionnelle des innovations évolutives: l'exemple de la cinématique et des performances de grimpe des chutes d'eau des juvéniles de gobies Résumé L'évolution de nouveaux traits fonctionnels peut contribuer significativement à la diversification des lignées. Les traits fonctionnels les plus anciens peuvent montrer plus de variabilité que les plus récents du fait de l'accumulation de changements évolutif au cours du temps. Cependant, ces prédictions peuvent être complexifiées par la diversité des fonctions et par l'implication de plusieurs structures dans une même fonction. Dans ce contexte, nous avons étudié la cinématique et les performances de grimpe des chutes d'eau de plusieurs espèces de gobies utilisant deux styles de grimpe originaux au sein de cette famille: le mode « powerburst ¼ plus ancestral et le mode « inching ¼ qui a évolué plus récemment. Le mode inching n'a été confirmé que pour deux espèces du même genre incluses au sein du clade des powerburst. Des vitesses de grimpe similaires entre les espèces utilisant le mode inching paraissent indiquer que ce mode de grimpe, qui a évolué plus récemment, présente une diversité fonctionnelle moins élevée. Toutefois, la similarité des vitesses de grimpe entre les deux espèces s'explique par des processus différents: le Sicyopterus stimpsoni d'Haiwaï se déplace plus lentement que le S. lagocephalus de La Réunion mais passe plus de temps en mouvement. La production de performances similaires, résultant de processus différents, reflète un phénomène semblable à celui de l'implication de plusieurs structures dans une même fonction. Si les mécanismes sous-jacents ne sont pas explorés, ces similarités peuvent perturber l'interprétation des différences relatives de diversité fonctionnelle entre les lignées. Par ailleurs, les performances de grimpe similaires entre certaines espèces utilisant le mode inching et d'autres le mode powerburst paraissent indiquer que la force de sélection sur les performances de grimpe est sans doute un facteur réduisant l'avantage évolutif du mode de grimpe inching. Dans ce contexte, d'autres mécanismes (e.g., exaptation) pourraient être à l'origine de cette innovation fonctionnelle. Translated to French by Raphael Lagarde (raph.lagarde@gmail.com).

PORTUGESE: Diversidade funcional de novidades evolucionárias: percepções da cinemática da escalada em cascatas e desempenho de peixes juvenis gobiídeos ResumoA evolução de novos traços funcionais pode contribuir substancialmente para a diversificação de linhagens. Os traços funcionais mais antigos podem mostrar maior variação do que as novidades desenvolvidas mais recentemente, devido ao acúmulo de mudanças evolutivas ao longo do tempo. No entanto, a complexidade funcional e os inúmeros mapeamentos de uma estrutura para uma única função podem complicar essas expectativas. Nesse contexto, comparamos a cinemática e a performance em juvenis de várias espécies para dois estilos de escalada em cascata que são novidades em peixes gobiídeos: a ancestral escalada por "explosão" e o evolutivamente mais recente chamado de "avançamento", que foi confirmado apenas entre espécies de um único gênero que dentro do clado de escaladores por explosão. Velocidades finais de escalada semelhantes entre espécies usando "avançamento" parecem, inicialmente, indicar que esse modo de escalada evolutivamente mais recente exibe menor diversidade funcional. No entanto, essas velocidades finais similares ocorrem por diferentes formas: Sicyopterus stimpsoni do Havaí se move mais devagar que S. lagocephalus das Ilhas Reunião, mas pode gastar mais tempo se movendo. Desempenhos semelhantes entre várias vias funcionais refletem uma situação que se assemelha ao fenômeno de mapeamento de uma estrutura para um única função. Essa semelhança tem o potencial de ocultar interpretações apropriadas sobre relativa diversidade funcional entre linhagens, a menos que os mecanismos que afetam o desempenho sejam explorados. Mais especificamente, a semelhança no desempenho final entre os estilos "explosão" e "avançamento"indica que a seleção na performance em escalada provavelmente foi um fator limitante na promoção da evolução por "avançamento" como um novo modo de escalada. Nesse contexto, outros processos (e.g., exaptação) podem estar relacionados com a origem dessa novidade funcional. Translated to Portuguese by Diego Vaz (dbistonvaz@vims.edu).

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The rapidly growing use of volumetric modulated arc therapy (VMAT) treatments in radiation therapy calls for a quantitative, automated, and reliable quality assurance (QA) procedure that can be used routinely in the clinical setting. In this work, we present a series VMAT QA procedures used to assess dynamic multi-leaf collimator (MLC) positional accuracy, variable dose-rate accuracy, and MLC leaf speed accuracy. The QA procedures were performed using amorphous silicon electronic portal imaging devices (EPID) to determine the long term stability of the measured parameters on two Varian linear accelerators. The measurements were repeated weekly on both linear accelerators for a period of three months and the EPID images were analyzed using custom Matlab software. The results of the picket fence tests indicate that MLC leaf positions can be identified to within 0.11 mm and 0.15 mm for static gantry delivery and VMAT delivery respectively. In addition, the dose-rate, gantry speed and MLC leaf speed tests both show very good stability over the measurement period. The measurements thus far, suggest that a number of the dosimetry tests may be suitable for quarterly QA for Varian iX and Trilogy linacs. However, additional measurements are required to confirm the frequency with which each test is required for safe and reliable VMAT delivery at our centre.

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Our image-guided radiation therapy (IGRT) protocol for post-prostatectomy patients involves acquiring a kV cone beam computed tomography (CBCT) dataset at each fraction and shifting the treatment couch to align the surgical clips. This IGRT strategy requires significant resources, and delivers non-negligible dose to normal tissues. The objective of this work is to evaluate this IGRT protocol against two alternative strategies in terms of the dose-volume statistics for target and organ at risk regions. Our method involves deforming the planning CT to the CBCT dataset acquired at each fraction, computing dose on the deformed dataset, and inversely transforming the dose back onto the original planning CT dataset. The treatments of six patients were evaluated assuming three IGRT scenarios: no IGRT, daily IGRT using the clinically employed couch shifts, and alternating day IGRT. The doses delivered to the clinical target volumes are within approximately 3.2, 1.3, and 2.1% of the plan for the non-IGRT, daily, and alternating day IGRT protocols, respectively. Doses to relevant portions of the organs at risk deviate from the plan by up to 10.5, 13.1 and 10.7% for non-IGRT, daily IGRT, and alternating day IGRT protocols, respectively. Some cases do not differ significantly between IGRT and non-IGRT protocols in terms of cumulative DVHs, highlighting the difficult task of correcting prostate bed deformations via the treatment couch translations. In general, the alternating day IGRT protocol was found to result in a clinically insignificant deviation in delivered dose while providing a significant reduction in resource use and patient imaging dose.

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HIV-related benign esophageal strictures have been reported secondary to idiopathic esophageal ulceration, cytomegalovirus (CMV) esophagitis, herpetic esophagitis, and increased sensitivity to radiation therapy. Despite extensive and deep nature of CMV ulceration, stricture formation is uncommon. There have been anecdotal reports of esophageal strictures secondary to CMV infection in HIV patients. Esophageal stricture has been reported during active CMV ulceration as well as subsequent to successful treatment. Esophageal strictures secondary to CMV have also been reported without prior ulceration. We report a patient with CMV esophagitis presenting with ulceration and stricture who developed total obliteration of esophageal lumen following treatment with gancyclovir.

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The effect of a magnetic field on the steady-state and time-resolved optical emission of a custom fullerene-linked photosensitizer (PS) in liposome cell phantoms was studied at various oxygen concentrations (0.19-190 microM). Zeeman splitting of the triplet state and hyperfine coupling, which control intersystem crossing between singlet and triplet states, are altered in the presence of low magnetic fields (B < 320 mT), perturbing the luminescence intensity and lifetime as compared to the triplet state at B = 0. Measurements of the luminescence intensity and lifetime were performed using a time-domain apparatus integrated with a magnet. We propose that by probing magnet-affected optical emissions, one can monitor the state of oxygenation throughout the course of photodynamic therapy. Since the magnetic field effect (MFE) operates primarily by affecting the radical ion pairs related to type I photodynamic action, the enhancement or suppression of the MFE can be used as a measure of the dynamic equilibrium between the type I and II photodynamic pathways. The unique photo-initiated charge-transfer properties of the PS used in this study allow it to serve as both cytotoxic agent and oxygen probe that can provide in situ dosimetric information at close to real time.

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Cells within the periodontal ligament have the potential to regenerate a periodontal connective tissue attachment on pathologically exposed root surfaces as well as on several material surfaces including titanium. However, rather than a periodontal connective tissue attachment, a fibrous encapsulation or chronic inflammatory response has been reported at the material connective tissue interface for most dental materials. Cementum is the first tissue of the periodontal connective tissue attachment to develop and the secretion of enamel matrix related proteins on the newly mineralized dentin surface precedes and is thought to induce cementum formation. Enamel matrix-related proteins may also function in the adult because the application of an acid extract of porcine enamel protein matrix (Emdogain(R), EMD) on pathologically exposed root surfaces has been shown to result in cementum regeneration. Therefore, the objective of the present study was to determine whether the application of EMD to materials that do not normally support cementogenesis in vivo would alter the in vitro phenotype of periodontal ligament (PDL) cells including the synthesis of cementum-associated extracellular matrix proteins. Primary PDL cells were established from 21-day-old Sprague-Dawley rats, and were cultured on four materials commonly encountered in dental practice (gutta percha, calcium hydroxide, amalgam, and super EBA cement) with and without the application of EMD. After 7 or 14 days of culture, total-DNA content, collagen synthesis, alkaline phosphatase activity, and the synthesis of a 42-kDa cementum-associated extracellular matrix protein were determined. PDL cells cultured on all materials had decreased total DNA content. The application of EMD further decreased total DNA content. PDL cells cultured on gutta percha and calcium hydroxide with the application of EMD had similar levels of collagen synthesis and alkaline phosphatase activity but also expressed a 42-kDa cementum extracellular matrix-associated protein when compared to the other groups. These results suggest that EMD can alter the phenotype of PDL cells when cultured on these dental materials.

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OBJECTIVE: This article focuses on the path to adoption for children involved in the public child welfare system. METHOD: Descriptive and event history analyses were conducted of 1,550 children who had been removed from their homes and placed in out of home care in the child welfare system in Kansas and have adoption as a goal. RESULTS: African American children consistently took longer to reach significant milestones, including adoption placement and finalization. CONCLUSION: African American children are over-represented throughout the progression from substantiated abuse to adoption. Future research in other states should focus on whether this trend is unique to Kansas or applicable in other states. Additionally, efforts should be devoted to investigating the social, psychological, cultural, and systemic factors contributing to this differential treatment. Finally, there is a dire need to develop and evaluate interventions targeted at meeting the specialized needs of African American children in this system.

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Measurement of the concentration of fluorescent compounds in turbid media is difficult because the absorption and multiple scattering of excitation and emission of light has a large effect on the detected fluorescence. For surface measurements with optical fibers we demonstrate by experiments and numerical simulation that this effect can be minimized by measurement of the fluorescence at one source-detector distance, the diffusely reflected excitation light at a second distance, and with the ratio of these two signals as an indicator of fluorophore concentration. For optical properties typical of soft tissue in the red and the near infrared the optimum performance is obtained by measurement of fluorescence at 0.65 mm and reflectance at 1.35 mm. This choice reduces the rms error in fluorophore concentration to 14.6% over a wide range of absorption and scattering coefficients.

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This study compares the photosensitizer concentration measured noninvasively in vivo by diffuse reflectance spectroscopy with the results of postmortem tissue solubilization and fluorometric assay. The reflectance spectrometer consists of a fiber optic surface probe, spectrometer and charge-coupled device (CCD) array detector. The surface probe has eight detection fibers separated from the light source fiber by distances ranging from 0.85 to 10 mm. The imaging spectrometer disperses the light from each detector fiber onto the two-dimensional CCD array, while maintaining spatial separation of each individual spectrum. A single exposure of the CCD therefore captures the reflectance spectrum ar eight distances and over a range of 300 nm. From the spectra, the tissue's optical scattering and absorption coefficients are determined using a diffusion model of light propagation. Changes in the tissue absorption are used to estimate the photosensitizer concentration. Normal New Zealand White rabbits were injected with aluminum phthalocyanine tetrasulfonate (AlPcS4) and probe measurements made 24 h after injection on the dorsal skin, on muscle after surgically turning the skin back and on liver. For skin, the noninvasive estimate to proportional to the true concentration but low by a factor of 3. Based on Monte Carlo modeling of multilayered systems, this underestimate is attributed to the layered structure of the skin and nonuniform AlPcS4 distribution. A comparison of the noninvasive concentration estimates to the postmortem assay results finds good agreement for liver tissue even though application of the diffusion model is not strictly justified.

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Changes in choices of preferred playmates by 3- and 4-year-old children were observed over the course of a school year. All of the children in this study participated in planned, fully mainstreamed, same-age preschool classes. Sociometric assessments were obtained from all children without disabilities in October, February, and May of the school year; peer nominations of three "best friends" were obtained at the beginning and end of the school year. The 3-year-old children showed a general decline in the ratings given to all of their peers over the course of the school year. Four-year-old children showed significant preferences for same-sex peers without disabilities as playmates. The implications of these findings for integrated programs are discussed.

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Relations between mothers' expectations and the performance of their infants with a disability on specific developmental tasks were explored. These mothers predicted their child's performance on developmental measures with accuracy levels comparable to those of parents of preschool children without disabilities. Children whose mothers were initially the most accurate in their estimations tended to show fewer gains in their statistically adjusted Bayley Mental Development Index scores over the course of the study. Mother's initial accuracy scores were found to account for substantial additional portions of the variance in the children's Bayley performances 14 and 28 weeks later.

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Hyperoxaluria occurs with many gastrointestinal disorders complicated by malabsorption. This hyperoxaluria is known to be the result of increased colonic absorption of dietary oxalate. Proposed mechanisms for this effect include alterations in fecal fatty acids, alterations in fecal bile acids, and acidification of colonic pH. Using an animal model of lactulose-induced chronic colonic acidification, we examined the effect of pH on oxalate absorption in vivo. Rats were fed a diet containing 6.77 mg oxalate per day with and without lactulose. Cecal pH of the animals receiving lactulose was significantly lower than controls (4.90 +/- 0.42 vs 7.17 +/- 0.38; p less than 0.001). Urinary excretion of oxalate was significantly greater in animals receiving the lactulose diet than in controls (0.975 +/- 0.144 vs 0.844 +/- 0.172 mg oxalate per day; p less than 0.001). These results demonstrate that acidification of the colon results in a significant increase in urinary oxalate excretion. Thus, acidification of the colon may be an important factor in the pathogenesis of enteric hyperoxaluria.

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This paper examines, from a SHPDA's perspective, major obstacles that must be overcome if the National Guidelines for Health Planning are to be viewed as more than a mechanism for "backdoor" regulation: (1) The acceptance of the guidelines by state government; (2) The location of the SHPDA/SHCC in the state's health policy structure; and (3) The lack of an informed general public. If the guidelines have only minimal impact on state priorities, the national policy will be both ineffective and coercive. HSAs, SHPDAs, and SHCCs, through public education, political action, and coordinated public pressure can assist in overcoming these obstacles and, if warranted, change the nature and focus of the content of the guidelines. A fourth obstacle, concerning the types of assistance and guidance provided to health planning agencies, suggests that DHEW has concentrated on using P.L. 93-641 as cost-containment mechanism to the neglect of issues that, in the long run, could have a positive effect on both the health system and health status.

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