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1.
Sci Data ; 11(1): 661, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38909030

ABSTRACT

In 2022, Houston, TX became a nexus for field campaigns aiming to further our understanding of the feedbacks between convective clouds, aerosols and atmospheric boundary layer (ABL) properties. Houston's proximity to the Gulf of Mexico and Galveston Bay motivated the collection of spatially distributed observations to disentangle coastal and urban processes. This paper presents a value-added ABL dataset derived from observations collected by eight research teams over 46 days between 2 June - 18 September 2022. The dataset spans 14 sites distributed within a ~80-km radius around Houston. Measurements from three types of instruments are analyzed to objectively provide estimates of nine ABL parameters, both thermodynamic (potential temperature, and relative humidity profiles and thermodynamic ABL depth) and dynamic (horizontal wind speed and direction, mean vertical velocity, updraft and downdraft speed profiles, and dynamical ABL depth). Contextual information about cloud occurrence is also provided. The dataset is prepared on a uniform time-height grid of 1 h and 30 m resolution to facilitate its use as a benchmark for forthcoming numerical simulations and the fundamental study of atmospheric processes.

2.
Sci Total Environ ; 512-513: 82-93, 2015 Apr 15.
Article in English | MEDLINE | ID: mdl-25613772

ABSTRACT

Green roofs alter the surface energy balance and can help in mitigating urban heat islands. However, the cooling of green roofs due to evapotranspiration strongly depends on the climatic conditions, and vegetation type and density. In the Southern Central Plains of the United States, extreme weather events, such as high winds, heat waves and drought conditions pose challenges for successful implementation of green roofs, and likely alter their standard performance. The National Weather Center Experimental Green Roof, an interdisciplinary research site established in 2010 in Norman, OK, aimed to investigate the ecological performance and surface energy balance of green roof systems. Starting in May 2010, 26 months of vegetation studies were conducted and the radiation balance, air temperature, relative humidity, and buoyancy fluxes were monitored at two meteorological stations during April-October 2011. The establishment of a vegetative community trended towards prairie plant dominance. High mortality of succulents and low germination of grasses and herbaceous plants contributed to low vegetative coverage. In this condition succulent diversity declined. Bouteloua gracilis and Delosperma cooperi showed typological dominance in harsh climatic conditions, while Sedum species experienced high mortality. The plant community diversified through volunteers such as Euphorbia maculate and Portulaca maculate. Net radiation measured at a green-roof meteorological station was higher than at a control station over the original, light-colored roofing material. These findings indicate that the albedo of the green roof was lower than the albedo of the original roofing material. The low vegetative coverage during the heat and drought conditions in 2011, which resulted in the dark substrate used in the green roof containers being exposed, likely contributed to the low albedo values. Nevertheless, air temperatures and buoyancy fluxes were often lower over the green roof indicating that higher evapotranspiration rates compensated for the higher net radiation at the green roof.


Subject(s)
Conservation of Natural Resources , Facility Design and Construction , Temperature , Poaceae
3.
Eur J Nutr ; 50(5): 379-86, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21103883

ABSTRACT

PURPOSE: Enterocytes are feasibly confronted with enormous zinc concentrations especially as a result of oral zinc supplementation. In the present study, we investigated the mechanisms underlying the exceptional ability to withstand this usually toxic load using the enterocytic cell line Caco-2. METHODS: By MTT test analysis, we compared zinc tolerance in undifferentiated Caco-2 cells (udCaco-2) and differentiated Caco-2 cells (dCaco-2). By RT-PCR, we compared the respective baseline expression levels of certain zinc transporters and metallothioneins (MTs) as well as the regulation of these components in response to high zinc concentrations. Moreover, using dCaco-2 cells cultured on porous membranes, we explored zinc tolerance in dependence of the side of zinc administration: apical versus basolateral. RESULTS: dCaco-2 cells tolerate significantly higher levels of zinc compared to udCaco-2 cells. This adaptation was accompanied by upregulated ZnT-1 and downregulated ZIP1 levels. The expression of metallothioneins MT1A and MT1X was also significantly downregulated during differentiation. Moreover, apparent from profound differences in zinc tolerance between apical and basolateral zinc application, polarization was concluded to have substantial impact on cellular zinc tolerance. CONCLUSIONS: The profound increase in zinc tolerance we found in differentiated enterocyte-type Caco-2 cells and in particular, the impact of polarization are likely to reflect the physiologically indispensable capability of enterocytes to cope with remarkable concentrations of intestinal zinc.


Subject(s)
Cell Differentiation , Enterocytes/drug effects , Zinc/metabolism , Caco-2 Cells , Carrier Proteins/metabolism , Cation Transport Proteins/genetics , Cation Transport Proteins/metabolism , Down-Regulation , Enterocytes/cytology , Humans , Intestinal Mucosa/metabolism , Metallothionein/genetics , Metallothionein/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Up-Regulation , Zinc/analysis
4.
Proc Nutr Soc ; 69(3): 416-20, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20550748

ABSTRACT

The health-promoting effects of lactic acid bacteria (LAB) are well recognised, making them a popular functional food ingredient. Commercially available probiotic products are often promoted as capable of improving immune defences also in healthy subjects. However, while strain-specific differences exist in the effects of LAB, conventional yoghurt bacteria have proved beneficial as well. For comparing the immunological effects of conventional and probiotic LAB, young healthy women received either a commercially available probiotic fermented milk product or a conventional yoghurt for four weeks. Both treatments showed comparable effects resulting in a stronger immunological reaction to stimuli (natural cytotoxicity against cancer cells, mitogen-induced T-lymphocyte activation and stimulated cytokine production). To study the mechanisms behind these effects, conventional (Lactobacillus delbrueckii) and probiotic (Lactobacillus rhamnosus GG), LAB were compared in vitro at the cellular level. Interestingly, L. rhamnosus GG was more potent in inducing maturation of dendritic cells (DC) that play a substantial role in directing the immune response to stimuli. In turn, L. delbrueckii provoked a higher secretion of proinflammatory cytokines as well as IL-10. These effects were, however, observed only after direct incubation of DC and LAB, not when both were separated by a layer of enterocyte-like Caco-2 cells. LAB also induced cytokine secretion in peripheral blood mononuclear cells in a similar manner and this effect was reduced in a Caco-2 cell model, suggesting a modulating influence of gut epithelial cells. While both conventional and probiotic strains modulate the immune response, specific properties may offer therapeutic options in the treatment of certain diseases.


Subject(s)
Cultured Milk Products/immunology , Immunologic Factors/pharmacology , Inflammation Mediators/metabolism , Lactobacillus/immunology , Probiotics , Adult , Caco-2 Cells , Cell Differentiation , Cytokines/metabolism , Dendritic Cells/cytology , Dendritic Cells/microbiology , Female , Humans , Interleukin-10/metabolism , Intestinal Mucosa/immunology , Intestinal Mucosa/metabolism , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Young Adult
5.
Biochimie ; 92(7): 880-4, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20347004

ABSTRACT

Lactoferrin (Lf) is a multifunctional glycoprotein. Due to its anti-inflammatory and anti-cancer properties and the resulting therapeutical potential, lactoferrin is at present focus of a variety of research areas. The regulation of cell growth represents one of the prominent performances of lactoferrin. In this study we found lactoferrin to inhibit proliferation of the human epithelial cancer cell line HeLa. The extent of this growth inhibition was comparable to the one induced by the transforming-growth-factor-beta-1 (TGFbeta1). In contrast to other cell lines where lactoferrin stimulates growth, lactoferrin failed to activate the MAP kinases ERK1/2 or p38 in HeLa cells. However, by immunocytochemistry and cell fractionation experiments, we found that lactoferrin is capable of activating the TGFbeta/Smad-2 pathway. The nuclear accumulation of Smad-2 induced by Lf was comparable in magnitude to the one induced by TGFbeta1. We therefore conclude that the canonical TGFbeta1 pathway is a feasible route for lactoferrin to transduce its antiproliferative effect in HeLa cells, when MAPkinase activation is absent.


Subject(s)
Cell Nucleus/drug effects , Cell Nucleus/metabolism , Lactoferrin/pharmacology , Smad2 Protein/metabolism , Animals , Cattle , Cell Proliferation/drug effects , Enzyme Activation/drug effects , HeLa Cells , Humans , Kinetics , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Protein Transport/drug effects , Transforming Growth Factor beta1/pharmacology , p38 Mitogen-Activated Protein Kinases/metabolism
8.
Epilepsy Behav ; 10(1): 44-8, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17126082

ABSTRACT

BACKGROUND: It is known that most adult patients with epilepsy often have poor knowledge of their disorder, treatment options, and social and vocational consequences, despite the huge amount of information available. Being pressed for time, health care professionals often are not able to provide the repetitive counseling and instruction necessary to address epilepsy care adequately. Therefore educational programs are considered extremely important in filling the gap. METHOD: For German-speaking countries, two educational programs called famoses, modulares Schulungsprogramm Epilepsie fur Familien [modular service package epilepsy for families], were developed by a multidisciplinary group of neuropediatricians, psychologists, social workers, and educators. The aims of the famoses programs are to improve children's and parents' knowledge about epilepsy and to help patients of childhood age and their parents achieve a better understanding of their disease, gain more self-confidence, and reduce specific fears regarding epilepsy. famoses comprises two different educational programs: famoses for kids with epilepsy within the developmental period of ages 7 to 13, and famoses for parents or caretakers. The programs are designed for interactive small-group education. RESULTS: The child-centered educational program is based on a fictional story: The children are sailors on a virtual cruise, sailing from island to island, accompanied by educated trainers. On each island there is something new to discover about epilepsy. The parent (and caretaker)-centered educational program covers different topics-overview and content of the program, basic knowledge, diagnostics, therapy, prognosis and development, and living with epilepsy-within six modules. The program was implemented in Germany and Switzerland in the spring of 2005 and is now operating in different epilepsy centers. CONCLUSION: Within comprehensive therapeutic management of epilepsy, educational programs for patients, and for parents (caretakers) of children with epilepsy, are considered to be extremely important. Such educational programs have two main goals: to increase knowledge about the disorder, and to strengthen the patients' responsibility for themselves, with the consequence of living with as few limitations as possible. famoses is an effective component of this comprehensive care. The program has been operating successfully in different epilepsy centers in Germany and Switzerland since the spring of 2005.


Subject(s)
Child of Impaired Parents/education , Epilepsy/psychology , Epilepsy/rehabilitation , Parents , Patient Education as Topic , Adolescent , Adult , Attitude to Health , Child , Female , Germany , Health Knowledge, Attitudes, Practice , Humans , Male , Surveys and Questionnaires , Switzerland
9.
J Biomech ; 38(4): 843-51, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15713306

ABSTRACT

Despite the introduction of new surgical techniques, the treatment of cartilage defects remains challenging. Delay or complete failure of cartilage healing is associated with problems in biological regeneration. The influence of mechanical conditions on this process, however, remains unevaluated. Osteochondral defects were generated on the left femoral condyle in 18 Yucatan minipigs. After 4, 6 and 12 weeks the defect filling, trabecular orientation and bone density were compared to the intact contralateral side. The mechanical straining during this period was then analyzed using an adaptive finite element technique. Histologically, the osteochondral defects showed bone resorption at the base and bone formation from the circumference. At 12 weeks, the macroscopically healed specimens showed fibrous cartilage formation, a minimally organized trabecular structure and increased trabecular volume fraction compared to the controls (p < 0.002). The amount of cancellous, cartilagineous, and fibrous tissue and the defect size as measured in histomorphometric analysis for the three time points (4, 6 and 12 weeks) was comparable in magnitude to that predicted by finite element analysis. The simulated osteochondral healing process was not fully capable of re-establishing a hyaline-like cartilage layer. The correlation between simulation and histology allows identification of mechanical factors that appear to have a larger impact on the healing of osteochondral defects than previously considered.


Subject(s)
Biomechanical Phenomena , Cartilage/injuries , Cartilage/physiology , Wound Healing , Animals , Bone Density , Bone Resorption , Cartilage/pathology , Female , Femur , Finite Element Analysis , Osteogenesis , Stress, Mechanical , Swine , Time Factors
10.
J Orthop Res ; 21(4): 662-9, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12798066

ABSTRACT

Interfragmentary movements affect the quality and quantity of callus formation. The mounting plane of monolateral external fixators may give direction to those movements. Therefore, the aim of this study was to determine the influence of the fixator mounting plane on the process of fracture healing. Identically configured fixators were mounted either medially or anteromedially on the tibiae of sheep. Interfragmentary movements and ground reaction forces were evaluated in vivo during a nine week period. Histomorphological and biomechanical parameters described the bone healing processes. Changing only the mounting plane led to a modification of interfragmentary movements in the initial healing phase. The difference in interfragmentary movements between the groups was only significant during the first post-operative period. However, these initial differences in mechanical conditions influenced callus tissue formation significantly. The group with the anteromedially mounted fixator, initially showing significantly more interfragmentary movements, ended up with a significantly smaller callus diameter and a significantly higher callus stiffness as a result of advanced fracture healing. This demonstrates that the initial phase of healing is sensitive to mechanical conditions and influences the course of healing. Therefore, initial mechanical stability of an osteosynthesis should be considered an important factor in clinical fracture treatment.


Subject(s)
Bony Callus/physiology , External Fixators , Fracture Healing/physiology , Tibial Fractures/physiopathology , Tibial Fractures/surgery , Animals , Female , Sheep , Stress, Mechanical , Torque , Torsion Abnormality , Weight-Bearing
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