THE EFFECTS OF FUTURE GLOBAL CHANGE ON ARBUSCULAR MYCORRHIZAL FUNGI AND SOIL CARBON: USING URBANIZATION AS A SURROGATE FOR FUTURE CONDITIONS IN FIELD STUDIES

Carbon, fixed photosynthetically by plants, cycles through plant, microbial biomass, soil, and atmospheric carbon pools. The effects of global change on this cycling will impact future levels of atmospheric carbon dioxide, but are poorly understood. In urban areas, temperature and carbon dioxide concentrations are often elevated to levels that simulate near-future climate changes. These elevations are not sudden, uniform step increases but are gradual and variable; as such urbanization may provide a means to simulate the effects of near-future climate changes. The dissertation research encompasses two studies utilizing urban macroclimate to study the effects of future climate change. In the first study, plots containing a common imported soil and seed bank were established at three locations along a 50 km urban-to-rural transect. In these plots, plant community development, temperature, carbon dioxide concentrations, and other factors had been monitored for five years. Subsequently, arbuscular mycorrhizal fungal structures in bulk soil were quantified. These fungi receive carbon directly from plant roots, grow into bulk soil, and can transfer immobile soil minerals to their plant hosts. In contrast to expectations, fewer fungal structures were found closer to the urban side of the transect. The second study was an observational study of soil carbon in minimally managed, long-undisturbed soils located at varying distances from urban areas. In sampling sites at 62 golf courses, similar communities of cool-season grasses had been undisturbed for at least 25 years. At each site, total and active soil carbon and many potential explanatory factors were measured and examined with multiple regression analysis. Contrary to expectations, soil carbon was positively correlated with warmer February-only mean daily minimum soil temperatures, suggesting that winter temperatures are more important than mean annual temperature for soil C storage in temperate grassland. Other correlations, including positive correlations with soil cation exchange capacity, soil lead levels, and tropospheric ozone exposure during the peak ozone season, were also detected. Potential mechanisms for the detected relationships are explored. The results of both experiments demonstrate that commonly-held expectations based on single-factor global change experiments or models are not always borne out in complex natural systems

Deriving polarity from granularity

In this paper, we present a way to unify Positive Polarity Items formed with some NP and minimizers, such as lift a finger. The connection is made via granularity properties of the two classes of polarity sensitive expressions. We begin with an observation in Strawson 1974 that the use of some NP involves an inference about the availability of a more precise identification of NP. Then, we show that the meaning of minimizers can be captured as the mirror image of the same granularity inference. To model our account, we use the granularity system in van Rooij 2011. We propose pragmatic requirements on the use of some NP and minimizers that explain both their granularity inferences and their polarity properties. Finally, we discuss how our proposal can be viewed as reconciliation of referential and alternative-based approaches to polarity

Cytochrome P450 CYP1B1 interacts with 8-<i>methoxypsoralen</i> (8-MOP) and influences psoralen-Ultraviolet A (PUVA) sensitivity

Background: There are unpredictable inter-individual differences in sensitivity to psoralen-UVA (PUVA) photochemotherapy, used to treat skin diseases including psoriasis. Psoralens are metabolised by cytochrome P450 enzymes (P450), and we hypothesised that variability in cutaneous P450 expression may influence PUVA sensitivity. We previously showed that P450 CYP1B1 was abundantly expressed in human skin and regulated by PUVA, and described marked inter-individual differences in cutaneous CYP1B1 expression.Objectives: We investigated whether CYP1B1 made a significant contribution to 8-methoxypsoralen (8-MOP) metabolism, and whether individuality in CYP1B1 activity influenced PUVA sensitivity.Methods: We used E. coli membranes co-expressing various P450s and cytochrome P450 reductase (CPR) to study 8-MOP metabolism and cytotoxicity assays in CYP1B1-expressing mammalian cells to assess PUVA sensitivity.Results: We showed that P450s CYP1A1, CYP1A2, CYP1B1, CYP2A6 and CYP2E1 influence 8-MOP metabolism. As CYP1B1 is the most abundant P450 in human skin, we further demonstrated that: (i) CYP1B1 interacts with 8-MOP (ii) metabolism of the CYP1B1 substrates 7-ethoxyresorufin and 17-b-estradiol showed concentration-dependent inhibition by 8-MOP and (iii) inhibition of 7-ethoxyresorufin metabolism by 8-MOP was influenced by CYP1B1 genotype. The influence of CYP1B1 on PUVA cytotoxicity was further investigated in a Chinese hamster ovary cell line, stably expressing CYP1B1 and CPR, which was more sensitive to PUVA than control cells, suggesting that CYP1B1 metabolises 8-MOP to a more phototoxicmetabolite(s).Conclusion: Our data therefore suggest that CYP1B1 significantly contributes to cutaneous 8-MOP metabolism, and that individuality in CYP1B1 expression may influence PUVA sensitivity

How HB 1222 Would Save Arkansas Money

Private school choice programs have a positive fiscal impact on states because the amount of state money spent on a child in the program, or the amount of state revenue foregone in the case of tax-credit funding, is less than the state would pay if the student attended a public school

How & Why The Arkansas Parental Empowerment For Education Choice Act of 2017 (HB 1222) Saves the State Money

The Education Savings Account (ESA) Program created by HB 1222 would save the state money because officials at the Department of Finance & Administration have to follow state law

Bringing Context Inside Process Research with Digital Trace Data

Context is usually conceptualized as “external” to a theory or model and treated as something to be controlled or eliminated in empirical research. We depart from this tradition and conceptualize context as permeating processual phenomena. This move is possible because digital trace data are now increasingly available, providing rich and fine-grained data about processes mediated or enabled by digital technologies. This paper introduces a novel method for including fine-grained contextual information from digital trace data within the description of process (e.g., who, what, when, where, why). Adding contextual information can result in a very large number of fine-grained categories of events, which are usually considered undesirable. However, we argue that a large number of categories can make process data more informative for theorizing and that including contextual detail enriches the understanding of processes as they unfold. We demonstrate this by analyzing audit trail data of electronic medical records using ThreadNet, an open source software application developed for the qualitative visualization and analysis of process data. The distinctive contribution of our approach is the novel way in which we contextualize events and action in process data. Providing new, usable ways to incorporate context can help researchers ask new questions about the dynamics of processual phenomena

Sleep apnea and the impact on cardiovascular risk in patients with Marfan syndrome

Background: Marfan syndrome (MFS) is an inherited connective tissue disorder characterized by ectopia lentis, aortic root dilation and dissection and specific skeletal features. Obstructive sleep apnea (OSA) in MFS has been described earlier but the prevalence and its relation with the cardiovascular risk is still controversial. This study aimed to further investigate these aspects. Methods: In this prospective longitudinal study, we performed an attended polysomnography in 40 MFS patients (60% women, 37 +/- 12.8 years) and evaluated several cardiovascular parameters through echocardiography, resting electrocardiogram, 24 hr-Holter monitoring and serum NT-ProBNP measurements. Results: We found that OSA was present in 42.5% of the patients and that higher body mass index was the most important factor associated with the presence of OSA. We observed that overweight was present in 27.5% of the patients in the whole cohort and in 55.6% if >40 years. Furthermore, when evaluating the impact of OSA on the cardiovascular system, we observed that patients with OSA tended to have higher systolic blood pressure, larger distal aortic diameters and a higher prevalence of ventricular arrhythmia. These differences were, however, not significant after adjusting for confounders. Conclusions: Our study shows a high prevalence of OSA and a high prevalence of overweight in MFS patients. We found some trends between OSA and cardiovascular features but we could not establish a solid association. Our study, however might be underpowered, and a multicenter collaborative study could be very useful to answer some important open questions

Proteomic Analysis of Media from Lung Cancer Cells Reveals Role of 14-3-3 Proteins in Cachexia

Aims: At the time of diagnosis, 60% of lung cancer patients present with cachexia, a severe wasting syndrome that increases morbidity and mortality. Tumors secrete multiple factors that contribute to cachectic muscle wasting, and not all of these factors have been identified. We used Orbitrap electrospray ionization mass spectrometry to identify novel cachexia-inducing candidates in media conditioned with Lewis lung carcinoma cells (LCM). Results: One-hundred and 58 proteins were confirmed in three biological replicates. Thirty-three were identified as secreted proteins, including 14-3-3 proteins, which are highly conserved adaptor proteins known to have over 200 binding partners. We confirmed the presence of extracellular 14-3-3 proteins in LCM via western blot and discovered that LCM contained less 14-3-3 content than media conditioned with C2C12 myotubes. Using a neutralizing antibody, we depleted extracellular 14-3-3 proteins in myotube culture medium, which resulted in diminished myosin content. We identified the proposed receptor for 14-3-3 proteins, CD13, in differentiated C2C12 myotubes and found that inhibiting CD13 via Bestatin also resulted in diminished myosin content. Conclusions: Our novel findings show that extracellular 14-3-3 proteins may act as previously unidentified myokines and may signal via CD13 to help maintain muscle mass