Nitrate Pathways, Processes, and Timing in an Agricultural Karst System: Development and Application of a Numerical Model

An edited version of this paper was published by AGU. Copyright 2019 American Geophysical Union.Nitrogen (N) contamination within agricultural‐karst landscapes and aquifers is widely reported; however, the complex hydrological pathways of karst make N fate difficult to ascertain. We developed a hydrologic and N numerical model for agricultural‐karst, including simulation of soil, epikarst, phreatic, and quick flow pathways as well as biochemical processes such as nitrification, mineralization, and denitrification. We tested the model on four years of nitrate (NO3−) data collected from a phreatic conduit and an overlying surface channel in the Cane Run watershed, Kentucky, USA. Model results indicate that slow to moderate flow pathways (phreatic and epikarst) dominate the N load and account for nearly 90% of downstream NO3− delivery. Further, quick flow pathways dilute NO3− concentrations relative to background aquifer levels. Net denitrification distributed across soil, epikarst, and phreatic water removes approximately 36% of the N inputs to the system at rates comparable to nonkarst systems. Evidence is provided by numerical modeling that NO3− accumulation via evapotranspiration in the soil followed by leaching through the epikarst acts as a control on spring NO3− concentration and loading. Compared to a fluvial‐dominated immature karst system, mature‐karst systems behave as natural detention basins for NO3−, temporarily delaying NO3− delivery to downstream waters and maintaining elevated NO3− concentrations for days to weeks after hydrologic activity ends. This study shows the efficacy of numerical modeling to elucidate complex pathways, processes, and timing of N in karst systems

CD8+ T Cells as a Source of IFN-γ Production in Human Cutaneous Leishmaniasis

Cutaneous leishmaniasis (CL) is usually a self-healing skin lesion caused by different species of Leishmania parasite. Resistance and susceptibility of mice to Leishmania major infection is associated with two types of CD4+ T lymphocytes development: Th1 type response with production of cytokine IFN-γ is associated with resistance, whereas Th2 type response with production of cytokines IL-4 and IL-5 is associated with susceptibility. A clear Th1/Th2 dichotomy similar to murine model is not defined in human leishmaniasis and we need as much information as possible to define marker(s) of protection. We purified CD4+/CD8+ T cells, stimulated them with Leishmania antigens and analysed gene and protein expression of Th1/Th2 cytokines in volunteers with a history of self-healing CL who are presumed to be protected against further Leishmania infection. We have seen significant upregulation of IFN-γ gene expression and high IFN-γ production in the Leishmania stimulated CD4+ T cells and CD8+ T cells. We concluded that both antigen-specific IFN-γ producing CD4+ Th1 cells and IFN-γ producing CD8+ T cells contribute to the long term protection in individuals with a history of CL. This proves the importance of CD8+ T cells as a source of IFN-γ in Th1-like immune responses

The biomechanics of rapid maxillary sutural expansion

Micro-displacements (fringe patterns) in the bones of the craniofacial complex as seen through laser holography during midpalatal sutural expansion with the Hyrax appliance are used to define the centers of rotation of the maxillary halves in both the frontal and occlusal views. Biomechanical analyses of the maxillary expansion force system are concomitant with the holographic findings and strongly suggest that the stainless steel wires joining the teeth to any expansion device be of the largest diameter possible. In addition, in the case of the Hyrax expansion device, it is recommended that the manufacturer increase the diameter of the activating screw as well as those of the 2 adjacent wire guides. And, importantly, the use of acrylic as a structural member to join the teeth to a sutural expansion device should be avoided if tipping of the maxillary halves is to be minimized, as the acrylic lacks sufficient rigidity.118325726

The Biomechanics Of Rapid Maxillary Suturai Expansion

Micro-displacements (fringe patterns) in the bones of the craniofacial complex as seen through laser holography during midpalatal sutural expansion with the Hyrax appliance are used to define the centers of rotation of the maxillary halves in both the frontal and occlusal views. Biomechanical analyses of the maxillary expansion force system are concomitant with the holographic findings and strongly suggest that the stainless steel wires joining the teeth to any expansion device be of the largest diameter possible. In addition, in the case of the Hyrax expansion device, it is recommended that the manufacturer increase the diameter of the activating screw as well as those of the 2 adjacent wire guides. And, importantly, the use of acrylic as a structural member to join the teeth to a suturai expansion device should be avoided if tipping of the maxillary halves is to be minimized, as the acrylic lacks sufficient rigidity.1183257261Barnes, R.E., The early expansion of deciduous arches and its effect on the developing permanent dentition (1956) Am J Orthod, 42, pp. 83-97Cheney, E.A., Indications and methods for the interception of functional crossbites and interlockings (1959) Dent Clin N Am, JULY, pp. 385-392Clifford, F.O., Crossbite correction in the deciduous dentition: Principles and procedures (1971) Am J Orthod, 59, pp. 343-349Davis, J.M., Why early treatment of crossbites? (1969) Dent Digest, 75, pp. 449-452Harvold, E., Some biological aspects of orthodontic treatment in the transitional dentition (1963) Am J Orthod, 49, pp. 1-14Moyers, R.E., (1974) Handbook of Orthodontics, 3rd Ed., , Chicago: Year Book Medical PublicationsRicketts, R.M., Early treatment (1979) J Clin Orthod, 13, pp. 181-199Kutin, G., Hawes, R.R., Posterior crossbites in the deciduous and mixed dentition (1969) Am J Orthod, 56, pp. 491-504Ficarelli, J.P., A brief review of maxillary expansion (1978) J Fed, 93, pp. 29-32Myers, D.R., Condylar position in children with functional posterior crossbites: Before and after crossbite correction (1980) Ped Dent, 2, pp. 190-194Haas, A.J., Rapid expansion of the maxillary dental arch and nasal cavity by opening of the mid-palatal suture (1961) Angle Orthod, 31, pp. 73-90Bishara, S.E., Staley, R.N., Maxillary expansion: Clinical implications (1987) Am J Orthod Dentofacial Orthop, 91, pp. 13-14Graber, T.M., (1972) Orthodontics: Principles and Practice, 3rd Ed., , Philadelphia: WB SaundersSims, J.M., (1972) Minor Tooth Movement in Children, , St Louis: MosbySchuler, R.J., (1975) Cephalometric Diagnosis of the Increase in Mandibular Arch Length by Utilizing Buccal Expansion for the Individual Patient, , Loma Linda UniversityCleall, J.F., Bayne, D.I., Posen, J.M., Subtelny, J.D., Expansion of the mid-palatal suture in the monkey (1965) Angle Orthod, 35, pp. 23-35Cotton, L.A., Slow maxillary expansion: Skeletal vs dental response to low magnitude force in Macaca Mulatta (1978) Am J Orthod, 73, pp. 1-23Hicks, E.P., Slow maxillary expansion: A clinical study of the skeletal vs dental response in low magnitude force (1978) Am J Orthod, 73, pp. 121-141Murray, J.M., Cleall, J.F., Early tissue response to rapid maxillary expansion in the mid-palatal suture of the rhesus monkey (1971) J Dent Res, 50, pp. 1654-1665Starnbach, H.K., Cleall, J.F., Effects of splitting the mid-palatal suture on the surrounding structures (1963) Am J Orthod, 50, pp. 923-932Starnbach, H.K., Bayne, D., Cleall, J., Subtelny, J.D., Facioskeletal and dental changes resulting from rapid maxillary expansion (1966) Angle Orthod, 36, pp. 152-164Bell, R.A., A review of maxillary expansion in relation to rate of expansion and patient's age (1982) Am J Orthod, 81, pp. 32-36Storey, E., Bone changes associated with tooth movement: A histologic study of the effect of force in the rabbit, guinea pig, and rat (1955) Aust Dent J, 59, pp. 147-158Storey, E., Bone changes associated with tooth movement: A histologic study of the effect of force for varying durations in the rabbit, guinea pig, and rat (1955) Aust Dent J, 59, pp. 209-220Brossman, R.E., Bennett, C.G., Merow, W.W., Facioskeletal remodeling resulting from rapid palatal expansion in the monkey (1973) Arch Oral Biol, 18, pp. 987-993Rune, B., Sarnas, K.V., Selvik, G., Jacobsson, S., Movement of maxillary segments after expansion and/or secondary bone grafting in cleft lip and palate: A roentgen stereogrammetric study with the aid of metallic implants (1980) Am J Orthod, 77, pp. 643-653Timms, D.J., A study of basal movement with rapid maxillary expansion (1980) Am J Orthod, 77, pp. 500-507Ekstrom, C., Henrikson, C.O., Jensen, R., Mineralization in the mid-palatal suture after orthodontic expansion (1977) Am J Orthod, 71, pp. 449-459Wertz, R.A., Skeletal and dental changes accompanying rapid mid-palatal suture opening (1970) Am J Orthod, 58, pp. 41-66Debbane, E.F., A cephalometric and histologic study of the effects of orthodontic expansion of the mid-palatal suture of the cat (1958) Am J Orthod, 44, pp. 187-219Bell, R.A., LeCompte, E.J., The effects of maxillary expansion using a quad-helix appliance during the deciduous and mixed dentitions (1981) Am J Orthod, 79, pp. 152-161Lee, K.G., Ryu, Y.K., Park, Y.C., Rudolph, D.J., A study of holographic interferometry on the initial reaction of maxillofacial complex during protraction (1997) Am J Orthod Dentofacial Orthop, 111, pp. 623-632Krag, G., Duterloo, H.S., TenBosch, J.J., The initial effect of the orthopedic forces: A study of alterations in the craniofacial complex of a macerated human skull (1982) Am J Orthod, 81, pp. 57-64Ichikawa, K., Nakagaw, M., Kamogashira, K., Hata, S., Itoh, T., Matsumoto, M., The effects of orthopedic forces on the craniofacial complex utilizing maxillary protraction (1984) J Jpn Orthod Soc, 43, pp. 325-336Dermaut, L.R., Beerden, L., The effect of class elastic force on a dry skull measured by holographic interferometry (1981) Am J Orthod, 79, pp. 294-304Pavlin, D., Vukicevic, D., Mechanical reactions of facial skeleton to maxillary expansion determined by laser holography (1984) Am J Orthod, 86, pp. 498-507Nanda, R., Golden, B., Biomechanical approaches to the study of the alterations of facial morphology (1980) Am J Orthod, 78, pp. 213-226Christiansen, R., Burstone, C.J., Centers of rotation within the periodontal space (1969) Am J Orthod, 55, pp. 353-369Marcotte, M.R., (1990) Biomechanics in Orthodontics, , Philadelphia: BC Decker, IncNanda, R., Protracting of the maxilla in rhesus monkeys by controlled extraoral forces (1978) Am J Orthod, 74, pp. 121-141Braun, S., Winzler, J., Johnson, B.E., An analysis of orthodontic force systems applied to the dentition with diminished alveolar support (1993) Eur J Orthod, 15, pp. 73-7