Chemical underpinning of the tea bag index: An examination of the decomposition of tea leaves

Decomposition is a key flux of terrestrial carbon to the atmosphere. Therefore, gaining a better understanding of how plant litter decomposes in soil, and what governs this process, is vital for global climate models. The Tea Bag Index (TBI) was introduced by Keuskamp et al. (2013) as a novel method for measuring litter decomposition rate and stabilisation. The TBI uses two types of tea bags representing fast (green tea) and slow (rooibos tea) decomposition substrates as standardised litter bags. To date, the TBI method has been used in over 2000 locations across the globe. However, before now, there has been no information on how the composition of the tea leaves change during incubation. These data are crucial in determining the validity of the use of the TBI method globally, to ensure the tea leaves decompose in a way that is representative of so-called “native” litters. To provide chemical underpinning of the TBI method, a laboratory incubation of the tea bags was conducted with destructive sampling at 0, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, and 91 d. The incubated tea was analysed for total C and N. In addition, C was characterised as alkyl, O-alkyl, aromatic, or carbonyl C using solid-state 13C nuclear magnetic resonance spectroscopy with cross-polarization and magic angle spinning (CPMAS NMR). The results suggest that changes in carbon in both tea types are comparable to other litter studies, with a net decrease in total C and relative proportion of O-alkyl C fraction, which contains carbohydrates and cellulose. We conclude that the decomposition of tea leaves in the bags used in the TBI is representative of other litters

Regulation of cAMP responses by the G12/13 pathway converges on adenylyl cyclase VII

Regulation of intracellular cyclic adenosine 3’, 5’-monophosphate (cAMP) by multiple pathways enables differential function of this ubiquitous second messenger in a context dependent manner. Modulation of Gs-stimulated intracellular cAMP has long been known to be modulated by the Gi and Gq/Ca2+ pathways. Recently, the G13 pathway was also shown to facilitate cAMP responses in murine macrophage cells. We report here that this synergistic regulation of cAMP synthesis by the Gs and G13 pathways is mediated by a specific isoform of adenylyl cyclase, AC7. Furthermore, this signaling paradigm exists in several hematopoietic lineages and can be recapitulated by exogenous expression of AC7 in HEK 293 cells. Mechanistic characterization of this synergistic interaction indicates that it occurs downstream of receptor activation and it can be mediated by the alpha subunit of either G12 or G13. Our results demonstrate that AC7 is a specific downstream effector of the G12/13 pathway

Scaled Physical Prototyping of Construction Processes Using 3D Printing

3D printing and Building Information Modelling (BIM) are two technologies that have become increasingly popular and changed a wide variety of applications in a significant manner. 3D printing enables the design, prototyping and manufacture of items that were previously impossible or infeasible to do. Similarly, BIM is changing the way building and civil infrastructure projects are conceived, designed, delivered and maintained with a push towards a digital, wholly collaborative construction environment.This paper examines how 3D printing and BIM can be used in a complimentary manner to help visualise and communicate important aspects of a project to the relevant stakeholders and personnel involved. By using the BIM model that has been developed for a specific project and segmenting key components of this model we can then use 3D printers to create a scaled model of the job and educate the concerned parties in the construction methodology, main risk areas, and ongoing concerns for maintenance and end-of-life deconstruction.

The Properties of Brightest Cluster Galaxies in X-Ray Selected Clusters

We present the K-band Hubble diagram for 162 brightest cluster galaxies (BCGs) in X-ray selected clusters, 0.01<z<0.83. The sample incorporates that of Burke, Collins, & Mann (2000) and includes additional infrared data from the 2MASS extended source catalogue. We show that below z=0.1 the BCGs show no correlation with their environment, however, above z=0.1 BCGs in more X-ray luminous clusters are more uniform in their photometric properties. This suggests that there may be two populations of BCGs which have different evolutionary histories.Comment: 2 pages, to appear in the proceedings of the Sesto 2001 conference on tracing cosmic evolution with galaxy cluster

3.3 Gigahertz Clocked Quantum Key Distribution System

A fibre-based quantum key distribution system operating up to a clock frequency of 3.3GHz is presented. The system demonstrates significantly increased key exchange rate potential and operates at a wavelength of 850nm.Comment: Presented at ECOC 05, Glasgow, UK, (September 2005

Frio pilot in CO2 sequestration in brine-bearing sandstones: The University of Texas at Austin, Bureau of Economic Geology, report to the Texas Commission on Environmental Quality to accompany a class V application for an experimental technology pilot injection well.

GEOSEQ project (LBNL, LLNL, ORNL), NETL, Schlumberger–Doll Research Center, Transpetco, Sandia TechnologiesJackson School of Geoscience

A comparison of physical soil organic matter fractionation methods for amended soils

Selecting a suitable physical fractionation method, to investigate soil organic matter dynamics, from the plethora that are available is a difficult task. Using five different physical fractionation methods, on soils either nontreated or with a history of amendment with a range of exogenous organic matter inputs (Irish moss peat; composted horse manure; garden compost) and a resulting range of carbon contents (6.8 to 22.2%), we show that method selection had a significant impact on both the total C recovered and the distribution of the recovered C between unprotected, physically protected, or chemically protected conceptual pools. These between-method differences most likely resulted from the following: (i) variation in the methodological fractions obtained (i.e., distinguishing between aggregate size classes); (ii) their subsequent designation to conceptual pools (e.g., protected versus unprotected); and (iii) the procedures used in sample pretreatment and subsequent aggregate dispersion and fractionation steps. The performance of each method also varied depending on the amendment in question. The findings emphasise the need for an understanding of the nature of the soil samples under investigation, and the stabilisation mechanism of interest, both prior to method selection and when comparing and interpreting findings from literature studies using different fractionation methods

Control of Black Root Rot in Dark Tobacco

Reports of the increasing prevalence of black root rot in the areas where dark tobacco types are grown has triggered an accelerated effort from the tobacco research staff to develop and release additional varieties with high resistance to this disease. The high level of resistance to black root rot found in Nicotiana debneyi (an Australian species) is being used as the source of resistance in the breeding program

Impact of the Algebra I End of Course Examination on African American Students Obtaining a Standard High School Diploma

The state of Florida requires all students complete Algebra I and pass the End of Course Examination (EOCE) to graduate with a standard high school diploma. Algebra I EOCE results indicate that many African American students do not pass the examination. This research sought to determine if there is a relationship between African American students’ failure to pass the Algebra I EOCE and graduate with a standard diploma. Four hypotheses, null and alternative were tested. Two ninth-grade cohorts, 2013-2014 and 2014-2015 comprised the sample. Data were analyzed using t test and one-way analyses of variance (ANOVA). Results indicate a significant relationship between African American students’ failure to pass the Algebra I EOCE and graduation with a standard high school diploma