Groundlayer Vegetation Ordination and Site-Factor Analysis of the Wright State University Woods (Greene County, Ohio)

Author Institution: Department of Biological Sciences, Wright State UniversityDetrended correspondence analysis (DECORANA) was used to examine groundlayer vegetation variation among seven locations of differing topography and successional age in the Wright State University woods (Greene County, OH). Two young sites (60 and 40 years since agricultural abandonment) and five older sites (one floodplain, one slope, and three uplands) were selected a priori and sampled four times in 1987. Taxon presences were recorded in 100 plots per location, and 12 environmental variables were measured from a subset of these plots. DECORANA ordination revealed that site age was the most important large scale factor affecting groundlayer vegetation. Topography was shown to be an important factor in the old growth sites. Stepwise linear regression with DECORANA plot scores as dependent variables and environmental factors as independent variables indicated that soil moisture content was the most important measured site factor associated with vegetation variation. This relationship was significant for vegetation along the overall successional gradient (r2 = 0.49) with soil moisture content positively correlated with site age. It was also significant along the old growth topographic gradient (r2 = 0.46) with soil moisture content negatively correlated with topographic elevation

Olfactory Recognition in Couples

The present study is an attempt to examine if couples can recognize the body odor of their significant other in a t-shirt worn for two days. Nine couples were in the experimental group (couples who had been dating at least six months), while the control group consisted of eight women and seven men (strangers to each other at the beginning of the study). The hypothesis that previous experience improves correct olfactory identification was not supported. When compared to women in the control group, men in the control group were better at recognizing their own shirt. When compared to men in the control group, women in the control group were better at identifying the shirt of a specific male participant

The flow of plasma in the solar terrestrial environment

The overall goal of our NASA Theory Program was to study the coupling, time delays, and feedback mechanisms between the various regions of the solar-terrestrial system in a self-consistent, quantitative manner. To accomplish this goal, it will eventually be necessary to have time-dependent macroscopic models of the different regions of the solar-terrestrial system and we are continually working toward this goal. However, with the funding from this NASA program, we concentrated on the near-earth plasma environment, including the ionosphere, the plasmasphere, and the polar wind. In this area, we developed unique global models that allowed us to study the coupling between the different regions. These results are highlighted in the next section. Another important aspect of our NASA Theory Program concerned the effect that localized 'structure' had on the macroscopic flow in the ionosphere, plasmasphere, thermosphere, and polar wind. The localized structure can be created by structured magnetospheric inputs (i.e., structured plasma convection, particle precipitation or Birkland current patterns) or time variations in these input due to storms and substorms. Also, some of the plasma flows that we predicted with our macroscopic models could be unstable, and another one of our goals was to examine the stability of our predicted flows. Because time-dependent, three-dimensional numerical models of the solar-terrestrial environment generally require extensive computer resources, they are usually based on relatively simple mathematical formulations (i.e., simple MHD or hydrodynamic formulations). Therefore, another goal of our NASA Theory Program was to study the conditions under which various mathematical formulations can be applied to specific solar-terrestrial regions. This could involve a detailed comparison of kinetic, semi-kinetic, and hydrodynamic predictions for a given polar wind scenario or it could involve the comparison of a small-scale particle-in-cell (PIC) simulation of a plasma expansion event with a similar macroscopic expansion event. The different mathematical formulations have different strengths and weaknesses and a careful comparison of model predictions for similar geophysical situations provides insight into when the various models can be used with confidence

The Flow of Plasma in the Solar-Terrestrial Environment

The overall goal of our NASA theory research is to trace the flow of mass, momentum, and energy through the magnetosphere-ionosphere-atmosphere system taking into account the coupling, time delays, and feedback mechanisms that are characteristic of the system. Our approach is to model the magnetosphere-ionosphere-atmosphere (M-I-A) system in a self-consistent quantitative manner using unique global models that allow us to study the coupling between the different regions on a range of spatial and temporal scales. The uniqueness of our global models stems from their high spatial and temporal resolutions, the physical processes included, and the numerical techniques employed. Currently, we have time-dependent global models of the ionosphere, thermosphere, polar wind, plasmasphere, and electrodynamics. It is now becoming clear that a significant fraction of the flow of mass, momentum, and energy in the M-I-A system occurs on relatively small spatial scales. Therefore, an important aspect of our NASA Theory program concerns the effect that mesoscale (100-l000 km) density structures have on the macroscopic flows in the ionosphere, thermosphere, and polar wind. The structures can be created either by structured magnetospheric inputs (i.e., structured electric field, precipitation, or Birkeland current patterns) or by time variations of these inputs due to geomagnetic storms and substorms. Some of the mesoscale structures of interest include sun-aligned polar cap arcs, propagating plasma patches, traveling convection vortices, subauroral ion drift (SAID) channels, gravity waves, and the polar hole

Relating Spatial Patterns of Stream Metabolism to Distributions of Juveniles Salmonids at the River Network Scale

Understanding the factors that drive spatial patterns in stream ecosystem processes and the distribution of aquatic biota is important to effective management of these systems and the conservation of biota at the network scale. In this study, we conducted field surveys throughout an extensive river network in NE Oregon that supports diminishing populations of wild salmonids. We collected data on physical habitat, nutrient concentrations, biofilm standing stocks, stream metabolism (gross primary production [GPP] and ecosystem respiration [ER]), and ESA‐listed juvenile salmonid density from approximately 50 sites across two sub‐basins. Our goals were to (1) to evaluate network patterns in these metrics, and (2) determine network‐scale linkages among these metrics, thus providing inference of processes driving observed patterns. Ambient nitrate‐N and phosphate‐P concentrations were low across both sub‐basins (\u3c40 μg/L). Nitrate‐N decreased with watershed area in both sub‐basins, but phosphate‐P only decreased in one sub‐basin. These spatial patterns suggest co‐limitation in one sub‐basin but N limitation in the other; experimental results using nutrient diffusing substrates across both sub‐basins supported these predictions. Solar exposure, temperature, GPP, ER, and GPP:ER increased with watershed area, but biofilm Chl a and ash‐free dry mass (AFDM) did not. Spatial statistical network (SSN) models explained between 70% and 75% of the total variation in biofilm Chl a, AFDM, and GPP, but only 21% of the variation in ER. Temperature and nutrient concentrations were the most supported predictors of Chl aand AFDM standing stocks, but these variables explained little of the total variation compared to spatial autocorrelation. In contrast, solar exposure and temperature were the most supported variables explaining GPP, and these variables explained far more variation than autocorrelation. Solar exposure, temperature, and nutrient concentrations explained almost none of the variation in ER. Juvenile salmonids—a key management focus in these sub‐basins—were most abundant in cool stream sections where rates of GPP were low, suggesting temperature constraints on these species restrict their distribution to oligotrophic areas where energy production at the base of the food web may be limited

Metabolic compensation constrains the temperature dependence of gross primary production

Gross primary production (GPP) is the largest flux in the carbon cycle, yet its response to global warming is highly uncertain. The temperature dependence of GPP is directly linked to photosynthetic physiology, but the response of GPP to warming over longer timescales could also be shaped by ecological and evolutionary processes that drive variation in community structure and functional trait distributions. Here, we show that selection on photosynthetic traits within and across taxa dampens the effects of temperature on GPP across a catchment of geothermally heated streams. Autotrophs from cold streams had higher photosynthetic rates and after accounting for differences in biomass among sites, biomass-specific GPP was independent of temperature in spite of a 20 °C thermal gradient. Our results suggest that temperature compensation of photosynthetic rates constrains the long-term temperature dependence of GPP, and highlights the importance of considering physiological, ecological and evolutionary mechanisms when predicting how ecosystem-level processes respond to warming

Stream hydraulics and temperature determine the metabolism of geothermal Icelandic streams

Stream ecosystem metabolism plays a critical role in planetary biogeochemical cycling. Stream benthic habitat complexity and the available surface area for microbes relative to the free-flowing water volume are thought to be important determinants of ecosystem metabolism. Unfortunately, the engineered deepening and straightening of streams for drainage purposes could compromise stream natural services. Stream channel complexity may be quantitatively expressed with hydraulic parameters such as water transient storage, storage residence time, and water spiralling length. The temperature dependence of whole stream ecosystem respiration (ER), gross primary productivity (GPP) and net ecosystem production (NEP = GPP−ER) has recently been evaluated with a “natural experiment” in Icelandic geothermal streams along a 5−25 ◦C temperature gradient. There remained, however, a substantial amount of unexplained variability in the statistical models, which may be explained by hydraulic parameters found to be unrelated to temperature. We also specifically tested the additional and predicted synergistic effects of water transient storage and temperature on ER, using novel, more accurate, methods. Both ER and GPP were highly related to water transient storage (or water spiralling length) but not to the storage residence time. While there was an additional effect of water transient storage and temperature on ER (r2 = 0.57; P = 0.015), GPP was more related to water transient storage than temperature. The predicted synergistic effect could not be confirmed, most likely due to data limitation. Our interpretation, based on causal statistical modelling, is that the metabolic balance of streams (NEP) was primarily determined by the temperature dependence of respiration. Further field and experimental work is required to test the predicted synergistic effect on ER. Meanwhile, since higher metabolic activities allow for higher pollutant degradation or uptake, river restoration and management should promote habitat diversity and complexity (hyporheic zone, macrophyte patches, substrate heterogeneity), especially for microbial activity.Le métabolisme des écosystèmes aquatiques fluviaux joue un rôle critique dans les cycles biogéochimiques planétaires. La complexité des habitats benthiques et l’aire disponible pour les microbes par rapport au volume d’eau qui s’écoule sont considérées comme des facteurs importants pour le métabolisme de l’écosystème. Malheureusement, le creusement et l’alignement des cours d’eau pour le drainage des terres pourraient compromettre les services naturels fournis par les cours d’eau. Cette complexité peut être exprimée quantitativement avec des paramètres hydrauliques tels que le stokage transitoire de l’eau dans le lit de la rivière, la durée de résidence du stockage transitoire, et la longueur du flux en hélice (ou spirale) de l’eau (distance moyenne parcourue par une molécule d’eau dans la zone d’eau courante libre avant d’entrer dans la zone calme). L’effet de la température sur la respiration globale des ruisseaux (ER), productivité primaire brute (GPP) et production nette de l’écosystème (NEP) a récemment été évalué au travers d’une « expérience naturelle » dans des ruisseaux géothermiques islandais le long d’un gradient de température de 5−25 ◦C. Il resta, cependant, une quantité substantielle de variabilité non expliquée par les modèles statistiques, qui pourrait être expliquée par les paramètres hydrauliques non reliés à la température. Nous avons aussi tout particulièrement testé les effets additionnels et en synergie du stokage transitoire de l’eau et de la température sur la respiration, en utilisant de nouvelles méthodes. ER and GPP furent hautement corrélées au stockage transitoire de l’eau (ou flux en hélice de l’eau), mais pas à la durée de résidence du stockage. Le stokage transitoire de l’eau et de la température eurent un effect additionnel sur ER (r2 = 0,57 ; P = 0,015), en revanche GPP était plus liée au stockage transitoire de l’eau qu’à la température. L’effet en synergie ne put être confirmé, probablement dû aux limitations des données. Notre interpretation, basée sur un modèle statistique causal, est que l’équilibre métabolique des cours d’eau (NEP) était principalement contrainte par la réponse de la respiration à la température. D’autres travaux de terrain et expérimentaux sont nécessaires pour tester notre nouvelle hypothèse d’un effet en synergie sur ER. Dans l’attente, puisqu’une plus haute activité métabolique permet une rétention ou dégradation plus importante des polluants, la restoration et la gestion des cours d’eau devraient promouvoir la diversité et la complexité des habitats (hyporhéos, touffes de macrophytes, hété- rogénéité du substrat) particulièrement pour l’activité microbienne.This study was funded by the Scottish Government Rural and Environment Research and Analysis Directorate (RERAD), now Rural and Environment Science and Analytical Services (RESAS). J.R.M. acknowledges the support of the Richard Stockton College of New Jersey. We would like to thank Tryggvi Thordarson, director of the Research Station at Hveragerdi for lodging and his warm hospitality, Marc Stutter and two anonymous referees for their insightful comments on the manuscript.Peer ReviewedRitrýnt tímari

Chimeric NKG2D receptor-bearing T cells as immunotherapy for ovarian cancer. Cancer Res

Abstract Despite advancements in the treatment of ovarian cancer, this disease continues to be a leading cause of cancer death in women. Adoptive transfer of tumor-reactive T cells is a promising antitumor therapy for many cancers. We designed a chimeric receptor linking NKG2D, a natural killer (NK) cellactivating receptor, to the CD3Z chain of the T-cell receptor to target ovarian tumor cells. Engagement of chimeric NKG2D receptors (chNKG2D) with ligands for NKG2D, which are commonly expressed on tumor cells, leads to T-cell secretion of proinflammatory cytokines and tumor cytotoxicity. In this study, we show that >80% of primary human ovarian cancer samples expressed ligands for NKG2D on the cell surface. The tumor samples expressed MHC class I-related protein A, MICB, and UL-16 binding proteins 1 and 3. ChNKG2D-expressing T cells lysed ovarian cancer cell lines. We show that T cells from ovarian cancer patients that express chNKG2D secreted proinflammatory cytokines when cultured with autologous tumor cells. In addition, we show that chNKG2D T cells can be used therapeutically in a murine model of ovarian cancer. These data indicate that treatment with chNKG2D-expressing T cells is a potential immunotherapy for ovarian cancer. [Cancer Res 2007;67(10):5003-8