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In this study, we investigated the effects of soil organic carbon (SOC) distribution and water uptake by plant roots on PFAS movement in the vadose zone with a deep groundwater table under temperate, humid climate conditions. Two series of numerical simulations were performed with the HYDRUS computer code, representing the leaching of historical PFOS contamination and the infiltration of water contaminated with PFOA, respectively. We considered soil profiles with three distributions of SOC (no SOC, realistic SOC distribution decreasing with depth, and uniform SOC equal to the content measured in topsoil), three root distributions (bare soil, grassland, and forest), and three soil textures (sand, sandy loam, and loam). The SOC distribution had a profound impact on the velocity of PFOS movement. The apparent retardation factor for realistic SOC distribution was twice as large as for the scenario with no SOC and more than three times smaller than for the scenario with uniformly high SOC content. We also showed that the root distribution in soil profoundly impacts the simulations of PFAS migration through soil. Including the root zone significantly slows down the movement of PFAS, primarily due to increased evapotranspiration and reduced downward water flux. Another effect of water uptake by plant roots is an increase of PFAS concentrations in soil water (evapo-concentration). The evapo-concentration and the slowdown of PFAS movement due to root water uptake are more significant in fine-textured soils than in sand., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The 2000-2001 and the 2022-2023 Taliban opium bans were and could be two of the largest ever disruptions to a major illegal drug market. To help understand potential implications of the current ban for Europe, this paper analyzes how opioid markets in seven Baltic and Nordic countries responded to the earlier ban, using literature review, key informant interviews, and secondary data analysis. The seven nations' markets responded in diverse ways, including rebounding with the same drug (heroin in Norway), substitution to a more potent opioid (fentanyl replacing heroin in Estonia), and substitution to one with lower risk of overdose (buprenorphine replacing heroin in Finland). The responses were not instantaneous, but rather evolved, sometimes over several years. This variety suggests that it can be hard to predict how drug markets will respond to disruptions, but two extreme views can be challenged. It would be naive to imagine that drug markets will not adapt to shocks, but also unduly nihilistic to presume that they will always just bounce back with no lasting effects. Substitution to another way of meeting demand is possible, but that does not always negate fully the benefits of disrupting the original market. Nonetheless, there is historical precedent for a European country's opioid market switching to synthetic opioids when heroin supplies were disrupted. Given how much that switch has increased overdose rates in Canada and the United States, that is a serious concern for Europe at present. A period of reduced opioid supply may be a particularly propitious time to expand treatment services (as Norway did in the early 2000s)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

This article addresses data privacy issues as they relate to multisystem collaborations for prearrest deflection into treatment and services for those suffering from a substance use disorder. The authors explore how the US data privacy regulations pose barriers to collaboration and care coordination and how data privacy regulations affect researchers' ability to evaluate the impact of interventions intentioned to facilitate access to care. Fortunately, this regulatory landscape is evolving to strike a balance between protecting health information and sharing it for research, evaluation, and operations, including comments on the newly proposed federal administrative rule that will shape the future of deflection and health access in the United States., (Copyright © 2023 International Society for Pharmacoeconomics and Outcomes Research, Inc. Published by Elsevier Inc. All rights reserved.)

We investigated the influence of climate change in the period 1951-2020 on shallow aquifers in the Brda and Wda outwash plains (Pomeranian Region, Northern Poland). There was a significant temperature rise (0.3 °C/10 years), which accelerated after 1980 (0.66 °C/10 years). Precipitation became increasingly irregular - extremely rainy years occurred right after or before extremely dry years, and intensive rainfall events became more frequent after 2000. The groundwater level decreased over the last 20 years, even though the average annual precipitation was higher than in the previous 50 years. We carried out numerical simulations of water flow in representative soil profiles for the years 1970-2020 using the HYDRUS-1D model, developed and calibrated during our earlier work at an experimental site in the Brda outwash plain (Gumuła-Kawęcka et al., 2022). We used a relationship between the water head and flux at the bottom of the soil profiles (the third-type boundary condition) to reproduce groundwater table fluctuations caused by recharge variability in time. The calculated daily recharge showed a decreasing linear trend for the last 20 years (0.05-0.06 mm d -1 /10 years), and dropping trends in water table level and soil water content in the entire profile of vadose zone. Field tracer experiments were performed to estimate impact of extremely rain events on water flux in vadose zone. The results suggest that tracer travel times are strongly determined by water content in the unsaturated zone which is determined by precipitation amount in span of weeks, rather than extremely high precipitation events., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

For nearly a century heroin has dominated the illegal opioid trade. The global supply of heroin is estimated to generate tens of billions of dollars in revenues a year and its illegal use has long been the source of many societal harms. The arrival of inexpensive and mass-produced synthetic opioids, such as fentanyl, to parts of North America and Europe may signal the beginning of the end of heroin's dominance. Data from several places suggest that fentanyl and other synthetic opioids can quickly supplant heroin. Taking the extreme case, we calculate the estimated wholesale revenues of heroin currently and contrast that with fentanyl prospectively in the United States and in the rest of the world if fentanyl were to supplant heroin entirely. Heroin traffickers in the United States generate about $2.5 billion in revenues; the total import value of fentanyl, after replacing heroin, could be less than $100 million. For the rest of the world we project a reduction from $6.7 billion to less than $300 million. Retailer revenues on the other hand would probably rise because individuals may consume more frequently and with greater intensity due to fentanyl's shorter duration of action and so far there has been no indication of a notable reduction in retail prices. It is unlikely that heroin will entirely disappear, but very likely that globally heroin will account for a declining share of illegal opioids. Violence and corruption may decline but opioid related mortality and morbidity, as well as property crime, are likely to rise. Policy makers will face difficult challenges. Economics provides limited help in forecasting which opioid markets are likely to convert to synthetic opioids., Competing Interests: Declarations of Interest None., (Copyright © 2020. Published by Elsevier B.V.)

The concentration of nonionic surfactants like Triton X-100 (TX100) can influence the transport and fate of emerging contaminants (e.g., carbon nanotubes) in porous media, but limited research has previously addressed this issue. This study investigates the co-transport of functionalized multi-walled carbon nanotubes (MWCNTs) and various concentrations of TX100 in saturated quartz sand (QS). Batch experiments and molecular dynamics simulations were conducted to investigate the interactions between TX100 and MWCNTs. Results indicated that the concentration ratio of MWCNTs and TX100 strongly influences the dispersion of MWCNTs and interaction forces between MWCNTs and QS during the transport. Breakthrough curves of MWCNTs and TX100 and retention profiles of MWCNTs were determined and simulated in column studies. MWCNTs strongly enhanced the retention of TX100 in QS due to the high affinity of TX100 for MWCNTs. Conversely, the concentration of TX100 had a non-monotonic impact on MWCNT retention. The maximum transport of MWCNTs in the QS occurred at an input concentration of TX100 that was lower than the critical micelle concentration. This suggests that the relative importance of factors influencing MWCNTs changed with TX100 sorption. Results from interaction energy calculations and modeling of competitive blocking indicate that the predictive ability of interaction energy calculations and colloid filtration theory may be lost because TX100 mainly altered intermolecular forces between the MWCNT and porous media. This study provides new insights into the co-transport of surfactants and MWCNTs in porous media, which can be useful for environmental applications and risk management., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Illegally manufactured potent synthetic opioids (IMPSO) like fentanyl have contributed to rises in overdose deaths in parts of North America and Europe. While many of these substances are produced in Asia, there is little evidence they have entered markets there. We consider the susceptibility to IMPSO's encroachment in markets in the Asia-Pacific region., Methods: Our analysis focuses on Australia, China, India, and Myanmar. Using a mixed-methods approach comprising interviews, literature review, and secondary data analyses, we examine factors facilitating or impeding incursion of IMPSO. Finally, we illustrate the potential for IMPSO fatalities in Australia., Results: Australia reports some signs of three facilitating factors to IMPSO's emergence: 1) existing illicit opioid markets, 2) disruption of opioid supply, and 3) user preferences. The other three countries report only existing illicit opioid markets. While diverted pharmaceutical opioids are a noted problem in Australia and India, heroin is the dominant opioid in all four countries. There are divergent trends in heroin use, with use declining in China, increasing in India, and stable in Australia and Myanmar. If IMPSO diffused in Australia as in North America from 2014 to 2018, and our assumptions generally hold, deaths from IMPSO could range from 1500-5700 over a five-year period., Conclusions: This analysis and illustrative calculations serve as an early indication for policymakers. With the exception of Australia, many countries in the region fail to properly record overdose deaths or monitor changes in local drug markets. Early assessment and monitoring can give officials a better understanding of these changing threats., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Some countries allow physicians to prescribe pharmaceutical-grade diamorphine to dependent users who have previously undergone treatment but are still using street-sourced heroin; this is not allowed in the US. This study provides the first nationally representative US data concerning public support for prescribing diamorphine to dependent users. We also test the hypothesis that calling it "diamorphine" instead of "heroin" increases support for this approach., Methods: The RAND American Life Panel is a nationally representative, probability-based survey of US adults. Of the 3345 panel members invited to take the survey, 2530 (75.6%) provided a valid response to our question module. Respondents were randomly assigned to have the question refer to the prescribed drug as either "heroin" or "diamorphine." The groups did not significantly differ on sex, age, race/ethnicity, or education. We compare the distribution of responses for the two groups and conduct Pearson's chi-squared test with the Rao-Scott correction., Results: For those asked whether the US should try prescribing pharmaceutical-grade "heroin," the share answering "Yes" (20.8%) was 15 percentage points lower than those responding "No" (35.8%). When the question asked about "diamorphine," the results were nearly reversed: the share answering "Yes" (30.6%) was almost 12 percentage points higher than those responding "No" (18.9%). The distributions of responses were significantly different (p < 0.001)., Conclusions: Support for prescribing diamorphine to dependent users is low in the US. While the results are consistent with the hypothesis that referring to heroin as diamorphine may reduce stigma associated with the substance and increase support for prescribing it, opinions may change as individuals learn they are different names for the same substance., (Copyright © 2019. Published by Elsevier B.V.)

Objectives: We report on five patients with gadolinium-negative (non-enhancing magnetic resonance imaging-MRI) but 18 F-fluoroethyl tyrosine positron-emission tomography (FET-PET) positive glioma (NEG) undergoing surgery under fluorescence-guidance with fluorescein sodium 10% (FL, Alkon, Germany) in combination with a dedicated light filter (YELLOW 560 nm, Carl Zeiss Meditec, Germany)., Patients and Method: Since 2017, five patients (3 female, 2 male; mean age 45.4 years) underwent fluorescence-guided surgery for supratentorial, intracerebral lesions which showed no contrast-enhancement in the preoperative MRI but were, however, strongly suspicious for gliomas. Accordingly, all patients received a preoperative FET-PET scan and detailed histopathological workup was performed. After giving written informed consent, all patients received 5 mg/kg of FL at the induction of anesthesia. Surgery was conducted under white light and under the YELLOW 560 nm filter. We reviewed the surgical protocols, navigational storage and the image databases of our surgical microscopes for evidence of intraoperative fluorescence that corresponded to the FET-PET positive area., Results: In all patients we found distinct accordances between the FET-PET positive areas and the fluorescing regions within the targeted lesions. Histopathological workup of the fluorescent tissue revealed anaplastic oligodendroglioma, IDH-mutant and 1p/19-codeleted (WHO grade III) (n = 2), anaplastic astrocytoma, IDH-mutant (WHO grade III) (n = 1), oligodendroglioma, IDH-mutant and 1p/19q-codeleted (WHO grade II) (n = 1) and pilocytic astrocytoma (WHO grade I) (n = 1). No adverse events were noted., Discussion and Conclusion: Despite the lack of gadolinium-enhancement in the preoperative MRI, all patients intravenously received FL to guide resection. Irrespective of the final grading, FL was extremely helpful in detecting the lesions and in identifying their border zones. In selected patients with NEG, but strong metabolic activity according to the FET-PET, FL may significantly increase the accuracy of surgery., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The aggregation of mostly antibody light chain variable (VL) domains into amyloid fibrils in various tissues is the main cause of death in systemic amyloid light chain amyloidosis. Point mutations within the domain are important to shift the VL into the fibrillar pathway, but why and how only some site-specific mutations achieve this still remains elusive. We show here that both destabilizing and surprisingly stable mutants readily predispose an amyloid-resistant VL domain to amyloid formation. The decreased thermodynamic stability of the destabilizing mutant results in the accumulation of non-native intermediates that readily populate the amyloid state. Interestingly, the stable mutants establish site-specific non-native interactions with especially nearby serine/threonine residues that unexpectedly do not affect the folding behavior of the VL domain but rather readily induce and stabilize the fibril structure, a previously unrecognized mechanism. These findings provide a new concept for the molecular mechanism of amyloid fibril formation., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Communication systems are exposed to two different pressures: a pressure for transmission efficiency, such that messages are simple to produce and perceive, and a pressure for referential efficiency, such that messages are easy to understand with their intended meaning. A solution to the first pressure is combinatoriality--the recombination of a few basic meaningless forms to express an infinite number of meanings. A solution to the second is iconicity--the use of forms that resemble what they refer to. These two solutions appear to be incompatible with each other, as iconic forms are ill-suited for use as meaningless combinatorial units. Furthermore, in the early stages of a communication system, when basic referential forms are in the process of being established, the pressure for referential efficiency is likely to be particularly strong, which may lead it to trump the pressure for transmission efficiency. This means that, where iconicity is available as a strategy, it is likely to impede the emergence of combinatoriality. Although this hypothesis seems consistent with some observations of natural language, it was unclear until recently how it could be soundly tested. This has changed thanks to the development of a line of research, known as Experimental Semiotics, in which participants construct novel communication systems in the laboratory using an unfamiliar medium. We conducted an Experimental Semiotic study in which we manipulated the opportunity for iconicity by varying the kind of referents to be communicated, while keeping the communication medium constant. We then measured the combinatoriality and transmission efficiency of the communication systems. We found that, where iconicity was available, it provided scaffolding for the construction of communication systems and was overwhelmingly adopted. Where it was not available, however, the resulting communication systems were more combinatorial and their forms more efficient to produce. This study enriches our understanding of the fundamental design principles of human communication and contributes tools to enrich it further., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Based on small-scale laboratory and field-scale lysimeter experiments, the sorption and biodegradation of sulfonamide sulfadiazine (SDZ) were investigated in unsaturated sandy and silty-clay soils. Sorption and biodegradation were low in the laboratory, while the highest leaching rates were observed when SDZ was mixed with manure. The leaching rate decreased when SDZ was mixed with pure water, and was smallest with the highest SDZ concentrations. In the laboratory, three transformation products (TPs) developed after an initial lag phase. However, the amount of TPs was different for different mixing-scenarios. The TP 2-aminopyrimidine was not observed in the laboratory, but was the most prevalent TP at the field scale. Sorption was within the same range at the laboratory and field scales. However, distinctive differences occurred with respect to biodegradation, which was higher in the field lysimeters than at the laboratory scale. While the silty-clay soil favored sorption of SDZ, the sandy, and thus highly permeable, soil was characterized by short half-lives and thus a quick biodegradation of SDZ. For 2-aminopyrimidine, half-lives of only a few days were observed. Increased field-scale biodegradation in the sandy soil resulted from a higher water and air permeability that enhanced oxygen transport and limited oxygen depletion. Furthermore, low pH was more important than the organic matter and clay content for increasing the biodegradation of SDZ. A numerical analysis of breakthrough curves of bromide, SDZ, and its TPs showed that preferential flow pathways strongly affected the solute transport within shallow parts of the soil profile at the field scale. However, this effect was reduced in deeper parts of the soil profile. Due to high field-scale biodegradation in several layers of both soils, neither SDZ nor 2-aminopyrimidine was detected in the discharge of the lysimeter at a depth of 1m. Synthetic 50 year long simulations, which considered the application of manure with SDZ for general agricultural practices in Germany and humid climate conditions, showed that the concentration of SDZ decreased below 0.1 μg/L in both soils below the depth of 50 cm., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The tumor suppressor protein p53 is often referred to as the guardian of the genome. In the past, controversial findings have been presented for the role of the C-terminal regulatory domain (RD) of p53 as both a negative regulator and a positive regulator of p53 activity. However, the underlying mechanism remained enigmatic. To understand the function of the RD and of a dominant phosphorylation site within the RD, we analyzed p53 variants in vivo and in vitro. Our experiments revealed, surprisingly, that the p53 RD of one subunit interacts with the DNA binding domain of an adjacent subunit in the tetramer. This leads to the formation of intersubunit contacts that stabilize the tetrameric state of p53 and enhance its transcriptional activity in a cooperative manner. These effects are further modulated by phosphorylation of a conserved serine within the RD., (Copyright © 2012. Published by Elsevier Ltd.)

Organic amendments often represent a source of trace metals (TMs) in soils, which may partly leach into the groundwater. The objectives of this study were (1) to validate Hydrus-2D for modeling the transport of Zn and Cu in an Alfisol amended with pig slurry (PS) by comparing numerical simulations and experimental field data, and (2) to model the next 50 years of TM movements under scenarios of suspended or continued PS amendments. First, between 2000 and 2008, we collected detailed Zn and Cu data from a soil profile in Santa Maria, Brazil. Two hypotheses about Zn and Cu reactivity with the solid phase were tested, considering physical, hydraulic, and chemical characteristics of six soil layers. Using a two-site sorption model with a sorption kinetic rate adjusted based on laboratory EDTA extractions, Hydrus simulations of the vertical TM transport were found to satisfactorily describe the soil Zn and Cu concentration profiles. Second, the long-term fate of Zn and Cu in the soil was assessed using the validated parameterized model. Numerical simulations showed that Zn and Cu did not present risks for groundwater pollution. However, future Cu accumulation in the surface soil layer would exceed the Brazilian threshold for agricultural soils., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The past decade has seen considerable progress in the development of models simulating pesticide transport in structured soils subject to preferential flow (PF). Most PF pesticide transport models are based on the two-region concept and usually assume one (vertical) dimensional flow and transport. Stochastic parameter sets are sometimes used to account for the effects of spatial variability at the field scale. In the past decade, PF pesticide models were also coupled with Geographical Information Systems (GIS) and groundwater flow models for application at the catchment and larger regional scales. A review of PF pesticide model applications reveals that the principal difficulty of their application is still the appropriate parameterization of PF and pesticide processes. Experimental solution strategies involve improving measurement techniques and experimental designs. Model strategies aim at enhancing process descriptions, studying parameter sensitivity, uncertainty, inverse parameter identification, model calibration, and effects of spatial variability, as well as generating model emulators and databases. Model comparison studies demonstrated that, after calibration, PF pesticide models clearly outperform chromatographic models for structured soils. Considering nonlinear and kinetic sorption reactions further enhanced the pesticide transport description. However, inverse techniques combined with typically available experimental data are often limited in their ability to simultaneously identify parameters for describing PF, sorption, degradation and other processes. On the other hand, the predictive capacity of uncalibrated PF pesticide models currently allows at best an approximate (order-of-magnitude) estimation of concentrations. Moreover, models should target the entire soil-plant-atmosphere system, including often neglected above-ground processes such as pesticide volatilization, interception, sorption to plant residues, root uptake, and losses by runoff. The conclusions compile progress, problems, and future research choices for modelling pesticide displacement in structured soils.

When soil structure varies in different soil types and the horizons of these soil types, it has a significant impact on water flow and contaminant transport in soils. This paper focuses on the effect of soil structure variations on the transport of pesticides in the soil above the water table. Transport of a pesticide (chlorotoluron) initially applied on soil columns taken from various horizons of three different soil types (Haplic Luvisol, Greyic Phaeozem and Haplic Cambisol) was studied using two scenarios of ponding infiltration. The highest infiltration rate and pesticide mobility were observed for the Bt(1) horizon of Haplic Luvisol that exhibited a well-developed prismatic structure. The lowest infiltration rate was measured for the Bw horizon of Haplic Cambisol, which had a poorly developed soil structure and a low fraction of large capillary pores and gravitational pores. Water infiltration rates were reduced during the experiments by a soil structure breakdown, swelling of clay and/or air entrapped in soil samples. The largest soil structure breakdown and infiltration decrease was observed for the Ap horizon of Haplic Luvisol due to the low aggregate stability of the initially well-aggregated soil. Single-porosity and dual-permeability (with matrix and macropore domains) flow models in HYDRUS-1D were used to estimate soil hydraulic parameters via numerical inversion using data from the first infiltration experiment. A fraction of the macropore domain in the dual-permeability model was estimated using the micro-morphological images. Final soil hydraulic parameters determined using the single-porosity and dual-permeability models were subsequently used to optimize solute transport parameters. To improve numerical inversion results, the two-site sorption model was also applied. Although structural changes observed during the experiment affected water flow and solute transport, the dual-permeability model together with the two-site sorption model proved to be able to approximate experimental data.

Although it has many positive effects, soil structure may adversely affect the filtering function of the vadose zone that protects natural water resources from various sources of pollution. Physically based models have been developed to analyze the impacts of preferential water flow (PF) and physical non-equilibrium (PNE) solute transport on soil and water resources. This review compiles results published over the past decade on the application of such models for simulating PF and PNE non-reactive tracer transport for scales ranging from the soil column to the catchment area. Recent progress has been made in characterizing the hydraulically relevant soil structures, dynamic flow conditions, inverse parameter and uncertainty estimations, independent model parameterizations, stochastic descriptions of soil heterogeneity, and 2D or 3D extensions of PNE models. Two-region models are most widely used across all scales; as a stand-alone approach to be used up to the field scale, or as a component of distributed, larger scale models. Studies at all scales suggest that inverse identification of parameters related to PF is generally not possible based on a hydrograph alone. Information on flux-averaged and spatially distributed local resident concentrations is jointly required for quantifying PNE transport. At the column and soil profile scale, model predictions of PF are becoming increasingly realistic through the implementation of the 3D soil structure as derived from hydrogeophysical and tracer techniques. At the field scale, integrating effects of the soil structure and its spatial variability has been attempted by combining 1D PNE approaches with stochastic parameter sampling. At the catchment area scale, the scarcity of data makes validation of PF related model components a task yet to be accomplished. The quest for easily measurable proxy variables, as 'the missing link' between soil structure and model parameters, continues in order to improve the practical predictive capability of PF-PNE models. A follow-up paper complementing this manuscript reviews model applications involving non-equilibrium transport of pesticides, as representatives of reactive solutes.

Introduction: Induction of apoptosis is a widely used strategy for cancer therapy, but evaluating the degree and success of this therapy still poses a problem. Radiolabeled annexin V has been proposed to be a promising candidate for detecting apoptotic cells in tumors following chemotherapy in vivo. In order to see whether radiolabeled annexin V could be a suitable substance for the noninvasive in vivo detection of apoptosis in thyroid tissue and to establish an optimized study protocol, we investigated two poorly differentiated thyroid carcinoma cell lines: ML-1 and FTC-133., Methods: Apoptosis was evaluated before as well as 2 and 4 days after in vitro irradiation with 30 Gy X-rays. In this study, binding of FITC- and of (125)I-labeled annexin V was measured in comparison to other apoptosis markers such as Bax, caspase-3 and Fas, which were determined by flow cytometry and Western blot analysis with densitometric evaluation., Results: ML-1 and FTC-133 cells showed a significant increase in annexin V binding 48 h after irradiation. Ninety-six hours after irradiation, the annexin V absorption capability of ML-1 cells was still maximal, while the living fraction of FTC-133 increased significantly. The amount of caspase-3 and Bax was clearly increased 48 h after irradiation and had normalized after 96 h in both cell lines. Fas protein concentrations remained unchanged in ML-1 cells but were significantly enhanced in FTC-133 cells., Conclusion: The binding of FITC- and (125)I-labeled annexin V showed a significant accordance. A reliable evaluation of apoptosis induced by radiotherapy in thyroid tumors was possible 48 h after irradiation, when binding of radiolabeled annexin V is most significantly enhanced. Using two poorly differentiated cell lines of thyroid carcinoma, one may expect to find a nearly similar response to external irradiation. In contrast, the cell lines showed a completely contrary response. However, an individualized study protocol for each type of tumor and probably within each type is necessary.

N-nitrosodimethylamine (NDMA) is a potential carcinogen frequently found in treated wastewater as a byproduct of chlorination. The potential for NDMA to contaminate the groundwater is a significant concern. A solute fate and transport model, Hydrus-1D, was used to evaluate the leaching potential of NDMA under different irrigation practices and soil properties. The results indicate that the risk of NDMA to reach the ground water is slim, when the reclaimed wastewater is applied under the customary conditions for landscape irrigation. The NDMA disappears in the reclaimed wastewater receiving soils rapidly through the microbial degradation and the volatilization processes. The factors that enhance the leaching risk are the soil hydraulic conductivity, the NDMA adsorption constants, and the irrigation intensity. When the hydraulic conductivity of soil is high, the NDMA adsorption constant of soil is low and/or the irrigation intensity is high, the NDMA leaching risk may dramatically increase. To reduce the NDMA leaching risk, it is imperative that the fields be irrigated at the proper volume and frequency and attention be paid to fields with soils having high-hydraulic conductivities and/or low-NDMA adsorption constants.

Vascular endothelial growth factor (VEGF) is a mitogenic, angiogenic, and potent mediator of vascular permeability. It plays a role in injuries, contributes to edema during the acute stage of tissue damage, and promotes repair during recovery. We recently showed that VEGF serum levels of burn patients with a considerable number of damaged vessels were significantly increased. Here, we study the effects of VEGF on healthy vessels treated with a comparable VEGF concentration achieved in patients suffering heavy burns. VEGF 165 (0.2 mL of 10 ng/mL) or vehicle (saline 0.9%) was intraluminally applied to umbilical arteries for 90 min at 37 degrees C. Then, the cord was perfused for 4 hr. During perfusion, functional and biochemical parameters were kept within normal physiological ranges. Afterward, the vessels were analyzed applying morphometry, sirius red staining, polarization microscopy, Western blot analysis, and immunohistochemistry. Moreover, cultured human umbilical vein endothelial cells (HUVECs) were treated with VEGF or vehicle for 90 min and 5.5 hr to examine extracellular matrix (ECM) proteins and receptor tyrosine kinases. VEGF-treated umbilical arteries showed significant tissue edema and simultaneously an enhancement of laminin and collagen types I, III, and IV compared with control arteries. We detected an increase in Flt-1, Flk-1, osteopontin, and ss(1)-integrin. VEGF induced laminin early in HUVECs as measured by flow cytometry. In parallel, VEGF induced a higher amount of osteopontin, ss(1)-integrin, and both receptor tyrosine kinases in endothelial cells within 90 min. Intraluminal application of VEGF enhances ECM protein, osteopontin, and ss(1)-integrin production of the endothelium, while it still generates tissue edema. VEGF initiates vascular remodeling as early as it generates edema, even if the target vessel is not damaged. Osteopontin and ss(1)-integrin, both induced by VEGF, may play an important role in the vascular remodeling process.

Antibiotics, such as sulfadiazine, reach agricultural soils directly through manure of grazing livestock or indirectly through the spreading of manure or sewage sludge on the field. Knowledge about the fate of antibiotics in soils is crucial for assessing the environmental risk of these compounds, including possible transport to the groundwater. Transport of (14)C-labelled sulfadiazine was investigated in disturbed soil columns at a constant flow rate of 0.26 cm h(-1) near saturation. Sulfadiazine was applied in different concentrations for either a short or a long pulse duration. Breakthrough curves of sulfadiazine and the non-reactive tracer chloride were measured. At the end of the leaching period the soil concentration profiles were determined. The peak maxima of the breakthrough curves were delayed by a factor of 2 to 5 compared to chloride and the decreasing limbs are characterized by an extended tailing. However, the maximum relative concentrations differed as well as the eluted mass fractions, ranging from 18 to 83% after 500 h of leaching. To identify relevant sorption processes, breakthrough curves of sulfadiazine were fitted with a convective-dispersive transport model, considering different sorption concepts with one, two and three sorption sites. Breakthrough curves can be fitted best with a three-site sorption model, which includes two reversible kinetic and one irreversible sorption site. However, the simulated soil concentration profiles did not match the observations for all of the used models. Despite this incomplete process description, the obtained results have implications for the transport behavior of sulfadiazine in the field. Its leaching may be enhanced if it is frequently applied at higher concentrations.

Model predictions of pesticide transport in structured soils are complicated by multiple processes acting concurrently. In this study, the hydraulic, physical, and chemical nonequilibrium (HNE, PNE, and CNE, respectively) processes governing herbicide transport under variably saturated flow conditions were studied. Bromide (Br-), isoproturon (IPU, 3-(4-isoprpylphenyl)-1,1-dimethylurea) and terbuthylazine (TER, N2-tert-butyl-6-chloro-N4-ethyl-1,3,5-triazine-2,4-diamine) were applied to two soil columns. An aggregated Ap soil column and a macroporous, aggregated Ah soil column were irrigated at a rate of 1 cm h(-1) for 3 h. Two more irrigations at the same rate and duration followed in weekly intervals. Nonlinear (Freundlich) equilibrium and two-site kinetic sorption parameters were determined for IPU and TER using batch experiments. The observed water flow and Br- transport were inversely simulated using mobile-immobile (MIM), dual-permeability (DPM), and combined triple-porosity (DP-MIM) numerical models implemented in HYDRUS-1D, with improving correspondence between empirical data and model results. Using the estimated HNE and PNE parameters together with batch-test derived equilibrium sorption parameters, the preferential breakthrough of the weakly adsorbed IPU in the Ah soil could be reasonably well predicted with the DPM approach, whereas leaching of the strongly adsorbed TER was predicted less well. The transport of IPU and TER through the aggregated Ap soil could be described consistently only when HNE, PNE, and CNE were simultaneously accounted for using the DPM. Inverse parameter estimation suggested that two-site kinetic sorption in inter-aggregate flow paths was reduced as compared to within aggregates, and that large values for the first-order degradation rate were an artifact caused by irreversible sorption. Overall, our results should be helpful to enhance the understanding and modeling of multi-process pesticide transport through structured soils during variably saturated water flow.

Objective: To determine differences between infertile wives' and husbands' levels of loneliness and perception of social support and to determine if there is a relationship between loneliness and social support., Design: Comparative descriptive., Setting: University infertility clinic and RESOLVE, an infertility support group., Participants: Convenience sample of 62 couples diagnosed as experiencing either primary or secondary infertility., Outcome Measures: Loneliness was measured using the Revised UCLA Loneliness Scale; social support was measured using the Interpersonal Relationship Inventory with subscales of Social Support, Reciprocity, and Conflict., Results: Wives were significantly more lonely than husbands (t = 2.053, p = 0.04). There was no significant group difference on the social support total score or three subscale scores. Loneliness was inversely related to social support and reciprocity both for wives (r = -0.62, p = 0.001, and r = -0.50, p = 0.002, respectively) and husbands (r = -0.74, p = 0.001, and r = -0.56, p = 0.001, respectively); loneliness correlated with conflict for wives only (r = 0.48, p = 0.007)., Conclusions: Although wives and husbands differed in loneliness, they were similar in perceived social support. Greater social support and reciprocity lessened feelings of loneliness for both groups. Wives who perceived increased conflict in their social relationships were more lonely.