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Observatory‐scale data collection efforts allow unprecedented opportunities for integrative, multidisciplinary investigations in large, complex watersheds, which can affect management decisions and policy. Through the National Science Foundation‐funded REACH (REsilience under Accelerated CHange) project, in collaboration with the Intensively Managed Landscapes‐Critical Zone Observatory, we have collected a series of multidisciplinary data sets throughout the Minnesota River Basin in south‐central Minnesota, USA, a 43,400‐km2tributary to the Upper Mississippi River. Postglacial incision within the Minnesota River valley created an erosional landscape highly responsive to hydrologic change, allowing for transdisciplinary research into the complex cascade of environmental changes that occur due to hydrology and land use alterations from intensive agricultural management and climate change. Data sets collected include water chemistry and biogeochemical data, geochemical fingerprinting of major sediment sources, high‐resolution monitoring of river bluff erosion, and repeat channel cross‐sectional and bathymetry data following major floods. The data collection efforts led to development of a series of integrative reduced complexity models that provide deeper insight into how water, sediment, and nutrients route and transform through a large channel network and respond to change. These models represent the culmination of efforts to integrate interdisciplinary data sets and science to gain new insights into watershed‐scale processes in order to advance management and decision making. The purpose of this paper is to present a synthesis of the data sets and models, disseminate them to the community for further research, and identify mechanisms used to expand the temporal and spatial extent of short‐term observatory‐scale data collection efforts. Observatory‐scale study of MN River Basin created integrative data sets and reduced complexity models to understand environmental changeData sets include water biogeochemistry, sediment sources and sinks, sediment fingerprinting, geomorphic change detection, and bathymetryModeling efforts focus on basin‐scale environmental transport to inform land management, reduce pollutant export, and improve river biota

Delta shoreline structure has long been hypothesized to encode information on the relative influence of fluvial, wave, and tidal processes on delta formation and evolution. We introduce here a novel multiscale characterization of shorelines by defining three process‐informed morphological metrics. We show that this characterization yields self‐emerging classes of morphologically similar deltas, that is, delta morphotypes, and also predicts the dominant forcing of each morphotype. Then we show that the dominant forcings inferred from shoreline structure generally align with those estimated via relative sediment fluxes, while positing that misalignments arise from spatiotemporal heterogeneity in deltaic sediment fluxes not captured in their estimates. The proposed framework for shoreline characterization advances our quantitative understanding of how shoreline features reflect delta forcings, and may aid in deciphering paleoclimate from images of ancient deposits and projecting delta morphologic response to changes in sediment fluxes. It has long been hypothesized that delta morphology and its evolution are primarily dictated by the interplay of three primary forcings: riverine, wave, and tidal. The rich diversity of delta morphologies observed across the globe is attributed to the relative dominance of those forcings. This study aims to retrieve the forcing information archived in delta morphology, specifically in the delta's shoreline, to establish a morphologic classification of deltas. To accomplish that, we propose a set of morphologic metrics targeting the specific locations and scales of the shoreline reworked by riverine, wave, and tidal processes. We show that the projection of the complex shoreline geometries into the low‐dimensional space defined by the proposed morphologic metrics leads to clusters of deltas with similar features, denoted here as morphotypes. Guided by the values of the metrics, we can infer the dominant forcings underlying each morphotype, which generally align with those obtained by estimating the sediment fluxes transported by each forcing. Misalignments are also observed and are mostly due to space‐time heterogeneities and uncertainties in the quantified sediment fluxes. Our methodology relies on readily‐available remote sensing images and is shown to have low sensitivity to its defining parameters, offering insight into predicting deltaic geomorphic response to changing forcings. Three process‐informed, geometric, and spectral metrics are introduced to characterize multiscale shoreline featuresUnsupervised clustering of the shoreline metrics reveals five distinct delta morphotypes which correspond to distinct forcingsMorphotypes can be robustly estimated from readily available satellite imagery Three process‐informed, geometric, and spectral metrics are introduced to characterize multiscale shoreline features Unsupervised clustering of the shoreline metrics reveals five distinct delta morphotypes which correspond to distinct forcings Morphotypes can be robustly estimated from readily available satellite imagery

We present a novel quantitative test of a 50‐year‐old hypothesis which asserts that river delta morphology is determined by the balance between river and marine influence. We define three metrics to capture the first‐order morphology of deltas (shoreline roughness, number of distributary channel mouths, and presence/absence of spits), and use a recently developed sediment flux framework to quantify the river‐marine influence. Through analysis of simulated and field deltas we quantitatively demonstrate the relationship between sediment flux balance and delta morphology and show that the flux balance accounts for at least 35% of the variance in the number of distributary channel mouths and 42% of the variance in the shoreline roughness for real‐world and simulated deltas. We identify a tipping point in the flux balance where wave influence halts distributary channel formation and show how this explains morphological transitions in real world deltas. River deltas are ecologically and economically important, and each delta is unique in terms of its environmental conditions and overall form. We test a 50‐year‐old hypothesis that qualitatively relates the overall form of a delta (in terms of its shoreline and channel network) to the balance between river and marine influence. We develop a suite of simulated river deltas using a physics‐based numerical model. We quantitatively describe the overall form for each of the simulated deltas and for a globally‐distributed set of real‐world deltas. The simulations and global deltas indeed exhibit relationships between their overall form and the balance of river and marine influence. Deltas with little to no marine influence have abundant channel mouths and rough shorelines. Tides act to roughen the shoreline but do not affect the number of distributary channel mouths. Waves tend to smooth the shoreline and reduce the number of distributary channel mouths. Waves may also lead to the formation of barrier islands and sand spits, though these features do not necessarily indicate wave “dominance.” These results confirm the hypothesis from the 1970's while adding important information about the morphological transitions between different end‐member “type” deltas. Physics‐based simulations reveal relationships between delta morphology and the balance of river, wave, and tidal sediment fluxesRivers create channels and tides roughen the shoreline, whereas waves smooth the shoreline, decrease channel number, and can create spitsThe simulations are consistent with the morphology of field deltas and confirm the 50‐year‐old hypothesis of Galloway (1975, https://archives.datapages.com/data/hgssp/data/022/022001/87_hgs0220087.htm) Physics‐based simulations reveal relationships between delta morphology and the balance of river, wave, and tidal sediment fluxes Rivers create channels and tides roughen the shoreline, whereas waves smooth the shoreline, decrease channel number, and can create spits The simulations are consistent with the morphology of field deltas and confirm the 50‐year‐old hypothesis of Galloway (1975, https://archives.datapages.com/data/hgssp/data/022/022001/87_hgs0220087.htm)

Progesterone (P4) maintains uterine quiescence during pregnancy and its functional withdrawal is associated with increased prostaglandin synthesis and the onset of labor. In primary human myometrial cells, the glucocorticoid receptor (GR) rather than the P4 receptor mediates P4 antagonism of IL-1β-induced cyclooxygenase-2 (COX-2) expression, the rate-limiting enzyme in prostaglandin synthesis. We now report that P4 also acts via GR to induce MAPK phosphatase (MKP)-1 and knockdown of MKP-1 impairs the ability of P4 to repress IL-1β-dependent COX-2induction. Microarray analysis revealed that P4 repressed preferentially activator protein-1-responsive genes in response to IL-1β. Consistent with these observations, we found that the ability of P4 to reduce c-Jun activation was lost upon GR as well as MKP-1 knockdown. Interestingly, c-Jun levels in human myometrial cells declined upon GR and MKP-1 knockdown, which suggests the presence of an activator protein-1 feedback loop. This is supported by our observation that c-Jun levels declined after an initial rise in primary myometrial cells treated with phorbol 12-myrisatate 13-acetate, a potent activator of c-Jun N-terminal kinase. Finally, we show that MKP-1 is an intermediate in P4-mediated repression of some but not all IL-1β-responsive genes. For example, P4 repression of IL11and IRAK3was maintained upon MKP-1 knockdown. Taken together, the data show that P4 acts via GR to drive MKP-1 expression, which in turn inhibits IL-1β-dependent c-Jun activation and COX-2expression.

Epigenetic modifications, which are heritable changes in gene expression not involving DNA sequence alterations, are important early events in the multi -step process of tumorigenesis. Among them, DNA methylation and histone acetylation are the most extensively studied. Although they are, by definition, somatically heritable, epigenetic modifications of DNA and histones are also reversible. This characteristic difference from genetic alterations makes them interesting targets for therapeutic intervention. The huge amount of knowledge gathered in the field of epigenetics the last decade, was followed by the development of novel therapies: old drugs finding new identity and new targets and an increasing list of novel compounds for the treatment of malignant diseases. Hematological malignancies offer a broad spectrum of diseases where epigenetic therapies are shown to be active, providing encouraging results. Some of the more recent reports on this field of therapeutic interventions are reviewed below.

Abstract: A composite multilayered coating which consisted of an electrodeposited Zn–Fe alloy layer, a zinc phosphate conversion layer, and one, two, or three organic layers was deposited on a mild steel substrate. The adhesion between these multilayered coating and the mild steel substrate was studied with the aid of a scratch testing technique. Observation of the worn surface of different multilayered coatings was performed with the aid of metallurgical microscopy. The same multilayered coatings were examined with FTIR spectroscopy and X-ray diffraction techniques. Finally, the corrosion behavior of bare and multilayered coated mild steel in 0.1 M NaCl solution (pH = 5.5, T = 25°C) was studied.

The wear behaviour of 5083 wrought aluminium alloy under the action of corrosive 3˙5% v/v NaCl solution, against stainless steel counterface was studied. Under a constant value of sliding speed, it was observed that the increase in the applied load resulted in a decrease in the friction coefficient of the pair stainless steel/Al 5083. Correlations have been also made between the various worn surfaces by electron optical microscopy. The dominant wear mechanisms of 5083 wrought aluminium alloy against stainless steel are believed to be intense plastic deformation and abrasive wear. During the corrosive wear experiments, pitting corrosion phenomena appeared on the surface of the worn specimen.

Seeking to assess the radiation risk associated with radiological examinations in neonatal intensive care units, thermo-luminescence dosimetry was used for the measurement of entrance surface dose (ESD) in 44 AP chest and 28 AP combined chest-abdominal exposures of a sample of 60 neonates. The mean values of ESD were found to be equal to 44 ± 16 µGy and 43 ± 19 µGy, respectively. The MCNP-4C2 code with a mathematical phantom simulating a neonate and appropriate x-ray energy spectra were employed for the simulation of the AP chest and AP combined chest-abdominal exposures. Equivalent organ dose per unit ESD and energy imparted per unit ESD calculations are presented in tabular form. Combined with ESD measurements, these calculations yield an effective dose of 10.2 ± 3.7 µSv, regardless of sex, and an imparted energy of 18.5 ± 6.7 µJ for the chest radiograph. The corresponding results for the combined chest-abdominal examination are 14.7 ± 7.6 µSv (males)/17.2 ± 7.6 µSv (females) and 29.7 ± 13.2 µJ. The calculated total risk per radiograph was low, ranging between 1.7 and 2.9 per million neonates, per film, and being slightly higher for females. Results of this study are in good agreement with previous studies, especially in view of the diversity met in the calculation methods.

In this work, a polymer gel–magnetic resonance (MR) imaging method is employed for the dosimetric characterization of a new 125I low dose rate seed (IsoSeed model I25.S17). Two vials filled with PABIG gel were prepared in-house and one new seed as well as one commercially available 125I seed of similar dose rate and well-known dosimetric parameters (IsoSeed model I25.S06) were positioned in each vial. Both seeds in each vial were MR scanned simultaneously on days 11 and 26 after implantation. The data obtained from the known seed in each vial are used to calibrate the gel dose response which, for the prolonged irradiation duration necessitated by the investigated dose rates, depends on the overall irradiation time. Data for this study are presented according to the AAPM TG-43 dosimetric formalism. Polymer gel results concerning the new seed are compared to corresponding, published dosimetric results obtained, for the purpose of the new seed clinical implementation, by our group using the established methods of Monte Carlo (MC) simulation and thermo-luminescence dosimetry (TLD). Polymer gel dosimetry yields an average dose rate constant value of Λ = (0.921 0.031) cGy h−1 U−1 relative to MC? = (0.929 0.014) cGy h−1 U−1, TLD? = (0.951 0.044) cGy h−1 U−1 and the average value of Λ = (0.940 0.051) cGy h−1 U−1 proposed for the clinical implementation of the new seed. Results for radial dose function, gL(r), and anisotropy function, F(r, θ), also agree with corresponding MC calculations within experimental uncertainties which are smaller for the polymer gel method compared to TLD. It is concluded that the proposed polymer gel–magnetic resonance imaging methodology could be used at least as a supplement to the established techniques for the dosimetric characterization of new low energy and low dose rate interstitial brachytherapy seeds.

Irreversible thermal conformational changes induced to collagen have been studied by optical methods. More specifically, second harmonic generation (SHG) from incident nanosecond Ng:YAG 1064 nm radiation and laser-induced fluorescence by 337 nm, pulsed nanosecond nitrogen laser excitation, at 405, 410 and 415 nm emission wavelengths were registered at eight temperatures (40°, 50°, 55°, 60°, 65°, 70°, 75° and 80°C) and normalised with respect to the corresponding values at the ambient temperature of 30°C. The heating protocol used in this work, was selected to monitor only permanent changes reflecting in the optical properties of the samples under investigation. In this context, the SHG, directly related to the collagen fibril population in triple helix conformation, indicated on irreversible phase transition around 64°C. On the other hand fluorescence related to the destruction of cross-linked chromophores in collagen, some of which are related to the triple helix tertiary structure, also indicated a permanent phase transition around 63°C. These results are in agreement with previous results from studies with differential scanning calorimetry. However SHG and fluorescence, being non-invasive optical methods are expected to have a significant impact in the fields of laser ablative surgery and laser tissue welding.

Abstract: . In the course of work aimed to examine second harmonic generation in biological macromolecules, it was discovered that 1064 nm pulsed nanosecond infrared laser radiation, after scattering on the optically rough sample surface, was perceived as double the fundamental frequency green speckle pattern by the unaided eye. The threshold of this arresting phenomenon was found to be around 60 mJ/cm2 on hyaluronic acid potassium salt in dark ambient conditions. This effect is of a second order non-linear nature. After experiments with nearsighted, farsighted and normal vision observers in combination with second harmonic generation experiments on various lamb eye tissues, the effect was mainly attributed to second harmonic generation in the cornea arising from phase interference of the incident infrared radiation. The current work could possibly have implications in the fields of speckle interferometry and biomedicine.

Abstract: A method for simulating field scale transport of kinetically adsorbing solutes is described. The non-equilibrium adsorption is modeled as a birth and death process and is coupled with the particle tracking approach using the first two moments of the distribution of the particle residence time, i.e., the time that a solute particle stays in the liquid phase. A single residence time distribution, regardless of the initial and final phase, is demonstrated to yield an accurate description of chemical kinetics in the vast majority of field scale problems. The first two moments of the residence time distribution are derived as a function of chemical reaction rates and the transport time interval Deltat. It is shown that the first moment of the residence time represents a measure of the speed of the chemical reaction relative to the transport time scale Deltat which is chosen depending on the velocity field. The second moment of the residence time reflects the relative importance of the chemical kinetics versus local equilibrium conditions for the given transport time step Deltat. The simulated spatial moments of the contaminant plume are compared in the one-dimensional case with available analytical solutions to demonstrate the accuracy of the proposed technique. A two-dimensional case for stratified formations is presented to study the transport behavior for heterogeneous velocity fields and variable distribution coefficient, hypothesized as being negatively correlated with hydraulic conductivity. The results show that the enhanced plume spreading and the statistics of the arrival time distribution appear to be more sensitive to the spatially variable distribution coefficient than to the kinetics alone. In fact, the second spatial moment was almost doubled in the case of spatially variable distribution coefficient.

An analysis of the errors due to the length of arc idealization in convective extended surfaces is presented. Longitudinal fins, spines, and annular fins of triangular profile are considered. It is shown that in fins that are designed according to the criteria established by Razelos and Georgiou [7], the resulting errors are negligibly small. These criteria suggest that fins should be designed with order of magnitude of aspect and Biot numbers of u = O(1) and Bi = O(0.01). It is also shown that for spines and annular fins only the Biot number restriction suffices to warrant negligible errors.

An analysis of the thermal performance of convective extended surfaces is presented that takes into account the primary function of the fins, which is to augment the heat transfer. The measure of the heat transfer augmentation is expressed by the removal number Nr, which we proposed should be O(10). It is shown that in order to satisfy this criterion the transverse Biot number hw/k must be of the order of 0.01. Further, it is argued that the fin is fully utilized if the aspect number is O(1). These criteria, Bi; = O(0.01) and u = 0(1), offer guidelines for designing fins and are applicable to longitudinal, annular, and pin fins, of uniform thickness or tapered profile. They must substitute the criterion that is frequently used, Bi < I, which was derived from the analysis of longitudinal fins. A very important consequence of this investigation is that fins designed to meet the above criteria can be analyzed using the classical one-dimensional method without introducing any appreciable error.

The stochastic storm transposition (SST) technique has been developed and evaluated in previous studies for the estimation of exceedance probabilities of extreme precipitation depths. In this study it is extended to the estimation of exceedance probabilities of extreme design floods. The link between storms and flood peaks is provided by a rainfall--runoff transformation and stochastic descriptions of antecedent moisture conditions and storm depth temporal distributions. Cumulative average catchment depths produced by the SST approach have been converted to a range of possible flood peak values using a rainfall--runoff model (the ARNO model) and a probabilistic disaggregation scheme of cumulative storm depths to hourly data. The analysis has been repeated for a range of fixed antecedent moisture conditions. The probabilities of exceedance of the produced flood peaks have been estimated and compared to highlight the effect of antecendent moisture conditions on the magnitude and frequency of produced floods as compared with the magnitude and frequency of the corresponding average catchment depths.

Abstract.: The aim of this study was to investigate the correlation of vertebral dimensions with somatometric parameters in patients without clinical symptoms and radiological signs of central lumbar spinal stenosis. One hundred patients presenting with low back pain or sciatica were studied with CT. In each of the L3, L4 and L5 vertebra three slices were taken with the following measurements: 1. Slice through the intervertebral disc: (a) spinal canal area; (b) interarticular diameter; (c) interligamentous diameter. 2. Slice below the vertebral arcus: (a) dural sac area; (b) vertebral body area. 3. Pediculolaminar level: (a) anteroposterior diameter and interpedicular diameter of the spinal canal; (b) spinal canal area; (c) width of the lateral recesses. The Jones-Thomson index was also estimated. The results of the present study showed that there is a statistically significant correlation of height, weight and age with various vertebral indices. The conventional, widely accepted, anteroposterior diameter of 11.5 mm of the lumbar spinal canal is independent of somatometric parameters, and it is the only constant measurement for the estimation of lumbar spinal stenosis with a single value. The present study suggests that there are variations of the dimensions of the lumbar spinal canal and correlations with height, weight and age of the patient.

Recent progress in the stabilization of laser-active color centers, the discovery of new color center lasers, and the development of new femtosecond sources in the infrared is discussed. The use of impurities such as oxygen to stabilize the F2+ center is described, followed by a description of the recently discovered N-center laser. Finally, the use of color center lasers to produce femtosecond pulses in the 1.5 µm region is reviewed.

An analysis of the thermal performance for convective annular fins, having a general trapezoidal profile and internal heat generation, is presented. The solution of the optimal problem is also given when either the heat dissipation rate or the volume of the fin is specified. The results are expressed in suitable nondimensional variables that are specified by the problem, and presented graphically. The effect of the fin's profile and thermal conductivity upon the optimum dimensions is discussed. It is shown that the presence of heat generation reduces the ability of the fin to convect heat. Furthermore, certain limiting values of the heat generation that may be imposed on the fin for a feasible optimization are also derived.

The aim of the present work was to obtain bone mass estimates of healthy Greek children aged 6–18 years. This work was considered worthwhile since similar data are very few in the world litterature (Bonnard 1968, Gryfe et al. 1971), while those for Greece (Livadas et al. 1975) refer to 902 children only (462 boys and 440 girls) aged 5–13 years.The material of the present study consists of 2.406 schoolboys and 2.451 schoolgirls aged 6–18 years, of whom 864 boys and 1.189 girls were living in Attica, while the remaining 1.542 boys and 1.262 girls were living in communities outside Attica (i.e. Atalanti, Arnea, Elatia and Karpenisi). Standing body height and body weight was measured in all subjects. Furthermore, a plain x–ray of the left hand was taken in all children, using a focal distance of 80 cm.By means of a micrometer apparatus (Taschenmessloupe TM4, C. Zeiss) the

Caroli's disease (congenital dilatation of the intrahepatic bile ducts) is a rare condition which is usually diagnosed postoperatively. Scintigraphic evaluation of this entity is very limited. We report here a patient with Caroli's disease in whom a dichotomy in hepatic uptake of 99mTc-HIDA (hot spots) and 99mTc-colloid (cold spots) was observed, leading to a correct preoperative evaluation of the disease.

The spleen was visualized in a 32-year-old patient with Hodgkin's disease (IIIB) and autoimmune haemolytic anaemia during a 99mTc-MDP bone scan. This visualization disappeared within 3 months with the regression of the haemolysis.

Hillslopes are typically shaped by varied processes which have a wide range of event‐based downslope transport distances, some of the order of the hillslope length itself. We hypothesize that this can lead to a heavy‐tailed distribution of displacement lengths for sediment particles. Here, we propose that such a behavior calls for a nonlocal computation of the sediment flux, where the sediment flux at a point is not strictly a function (linear or nonlinear) of the gradient at that point only but is an integral flux taking into account the upslope topography (convolution Fickian flux). We encapsulate this nonlocal behavior in a simple fractional diffusive model which involves fractional derivatives, with the order of differentiation (1 < α≤ 2) dictating the degree of nonlocality (α= 2 corresponds to linear diffusion and strictly local dependence on slope). The model predicts an equilibrium hillslope profile which is parabolic close to the ridgetop and transits, at a short downslope distance, to a power law with an exponent equal to the parameter αof the fractional transport model. Hillslope profiles reported in previously studied sites support this prediction. Furthermore, we show that the nonlocal transport model gives rise to a nonlinear dependency on local slope and that variable upslope topography leads to widely varying rates of sediment flux for a given local hillslope gradient. Both of these results are consistent with available field data and suggest that nonlinearity in hillslope flux relationships may arise in part from nonlocal transport effects in which displacement lengths increase with hillslope gradient. The proposed hypothesis of nonlocal transport implies that field studies and models of sediment fluxes should consider the size and displacement lengths of disturbance events that mobilize hillslope colluvium.

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The case reported by McHugh et al (1988) refers to their interesting observation that in a patient with chronic lymphocytic leukaemia, complicated by a Coombs-positive haemolytic anaemia, 99Tcm-MDP(methylene disphosphonate), a bone scanning agent, was selectively concentrated in the spleen.