Effect of nitrogen fertilization on caffeine production in coffee (Coffea arabica)

Nitrogen (N) based secondary metabolite production is thought to be costly to plants because N is required for growth, as well as, the synthesis of these compounds. Therefore, variation in N availability may result in variation in N-based secondary metabolite production. Here, we determine the effect of N fertilization on caffeine (N-based alkaloid) production in coffee (Coffea arabica) seedlings. A growth chamber experiment was performed with three N treatments applied to seedlings. N fertilization increased plant growth, leaf biomass, and plant N. Caffeine concentration in phloem exudates was greater in high-N fertilized plants relative to intermediate- and low-N plants. However, leaf, stem, root, and total overall caffeine concentration and content did not differ across N treatments. These results suggest caffeine in coffee is strongly regulated by genetic factors, and environment is likely less important to caffeine phenotype. This is among the first studies to investigate the effect of N fertilization on caffeine within the phloem, which has important implications for herbivores that are sensitive to caffeine and plant N and feed from the phloem of coffee.     

Surface chemistry of dihydromyrcenol (2,6-dimethyl-7-octen-2-ol) with ozone on silanized glass,glass, and vinyl flooring tiles

The surface-phase reaction products of dihydromyrcenol (2,6-dimethyl-7-octen-2-ol) with ozone (O₃), air, or nitrogen (N₂) on silanized glass, glass and vinyl flooring tile were investigated using the recently published FACS (FLEC (Field and Laboratory Emission Cell) Automation and Control System). The FACS was used to deliver ozone (100 ppb), air, or N₂ to the surface at a specified flow rate (300 mL min^?1) and relative humidity (50%) after application of a 2.0% dihydromyrcenol solution in methanol. Oxidation products were detected using the derivatization agents: O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) and N,O-bis(trimethysilyl)trifluoroacetamide (BSTFA). The positively identified reaction products were glycolaldehyde, 2,6-dimethyl-5-heptenal, and glyoxal. The proposed oxidation products based on previously published VOC/O₃ reaction mechanisms were: 2,6-dimethyl-4-heptenal, 6-methyl-7-octen-2-one and the surface-specific reaction products: 6-methyl-6-hepten-2-one, 6-methyl-5-hepten-2-one, and 6-hydroxy-6-methylheptan-2-one. Though similar products were observed in gas-phase dihydromyrcenol/O₃ reactions, the ratio, based on peak area, of the reaction products was different suggesting stabilization of larger molecular weight species by the surface. Emission profiles of these oxidation products over 72 h are also reported.     

The impact of non-invasive prenatal testing on anxiety in women considered at high or low risk for aneuploidy after combined first trimester screening

Objective: The aim of this study was to (1) examine the psychological impact of non-invasive prenatal testing (NIPT) in women with a high-risk (≥1 : 300) and low-risk (≤1 : 301) result on combined first trimester screening (cFTS) and (2) to examine factors influencing anxiety and decision-making in both risk populations. Method: Questionnaires and structured interviews were administered to low (n = 50) and high (n = 63) risk women at the time of NIPT blood draw (point A) and again at least 1 week after receiving their NIPT result (point B). Anxiety levels were measured at these two time points using the State–Trait Anxiety Inventory. Results: Both high-risk and low-risk cFTS groups demonstrated similar intrinsic (trait) anxiety levels (36 ± 10 vs 35 ± 10; p = 0.70). High-risk women had significantly higher levels of state anxiety at point A than low-risk women (42 ± 11 vs 36 ± 11; p < 0.01). Both groups had a statistically significant reduction (p < 0.01), to similar final levels of state anxiety at point B (30 ± 11 vs 29 ± 8; p = 0.61). Conclusion: Women receiving a high-risk result on cFTS have higher levels of state anxiety than their low-risk counterparts. Following a low-risk NIPT result, the anxiety levels in both populations are reduced to similar levels. © 2017 John Wiley & Sons, Ltd.     

Cell-free DNA screening in twin pregnancies: A more accurate and reliable screening tool

Objective

Outcome data from cell-free DNA (cfDNA) screening in twin gestations are limited. This study adds an appreciable number of confirmed outcomes to the literature, and assesses performance of cfDNA screening in twins over a 4.5-year period at one large clinical laboratory.

Method

Prenatal cytogenetic and SNP microarray results were cross-referenced with cfDNA results for twin pregnancies, yielding 422 matched cases. Using diagnostic results as truth, performance of cfDNA screening in this population was assessed.

Results

Of the 422 twin pregnancies with both cfDNA and diagnostic results, 3 specimens failed amniocyte analysis, and 48 samples (11.5%) were nonreportable from the initial cfDNA draw. Analysis of the 371 reportable samples demonstrated a collective sensitivity of 98.7% and specificity of 93.2% for trisomies 21/18/13. Positive predictive values (PPVs) in this study population, which is enriched for aneuploidy, were 78.7%, 84.6%, and 66.7% for trisomy 21, 18, and 13, respectively.

Conclusion

CfDNA screening in a cohort of twin pregnancies with matched diagnostic results showed superior performance compared to traditional serum biochemical screening in twins. This study adds to a growing body of evidence suggesting that cfDNA is an accurate and reliable screening tool for the major trisomies in twin pregnancies.

     

Hands-on assistance improves already successful pollution prevention services of the toxics use reduction institute’s laboratory

In an attempt to improve the adoption rate of the work conducted at the Toxics Use Reduction Institute Lab, a more comprehensive on-site follow-up assistance program was implemented in 2006. The effort was piloted for trichloroethylene replacement in Rhode Island in conjunction with Environmental Protection Agency (EPA) Region 1.Through hands-on workshops and on-site assistance efforts, the TURI Lab project was able to achieve an 82% reduction in TCE in a two year period. This new methodology for on-site assistance follow-up to the preexisting TURI Lab testing program has been incorporated into the work the Lab conducts for companies in Massachusetts. The Lab had an implementation rate of around 30% without on-site assistance. During the first year of the new process, the adoption rate has jumped to 80% of all companies working with the lab.     

Reproductive success in a low skew, communal breeding mammal: the banded mongoose, Mungos mungo

In most cooperatively breeding species, reproduction is monopolised by a subset of group members. However, in some species most or all individuals breed. The factors that affect reproductive success in such species are vital to understanding why multiple females breed. A key issue is whether or not the presence of other breeders is costly to an individual’s reproductive success. This study examines the factors that affect the post-parturition component of reproductive success in groups of communal-breeding banded mongoose (Mungos mungo), where up to ten females breed together. Per-litter reproductive success was low (only 18% of pups survived from birth to independence). Whilst singular breeding was wholly unsuccessful, there were costs associated with breeding in the presence of increasing numbers of other females and in large groups. Synchronisation of parturition increased litter success, probably because it minimises the opportunity for infanticide or decreases competitive asymmetry between pups born to different females. There was no evidence of inbreeding depression, and reproductive success was generally higher in litters where females only had access to related males within their group. I conclude that communal breeding in female banded mongooses represents a compromise between the benefits of group-living and communal pup care on the one hand, and competition between females to maximise their personal reproductive success on the other. Such conflicts are likely to occur in most communal breeding species. Whilst communal breeding systems are generally considered egalitarian, negative effects of co-breeders on individual reproductive success is still an issue.     

Field-focusing nuclear magnetic resonance (FONAR)

A technique, field-focusing NMR (FONAR), is described for doing NMR scans in large samples. The method utilizes a shaped D.C. magnetic field that confines the NMR-signal-producing region of the sample to a small volume called the resonance aperture. The aperture contains the required values of the Ho field to fully bracket the band of the r.f. pulse. The magnet system and r.f. pick-up coil that achieved the first human NMR can is discussed.     

A predictive study of emotional labor and turnover

The current study examined how the emotional labor strategies of deep acting and surface acting directly influence emotional exhaustion and turnover intentions, and indirectly impact actual turnover among a sample of bank tellers. Turnover data were collected from organizational records 6 months after participants responded to a survey that measured emotional labor strategies, emotional exhaustion, and turnover intentions. Results showed that turnover intentions mediated the relationship between deep acting and actual turnover. Additionally, surface acting had indirect effects on turnover through emotional exhaustion and turnover intentions. Copyright © 2009 John Wiley & Sons, Ltd.     

Solid phase microextraction of aminodinitrotoluenes in tissue

Tubifex tubifex metabolizes 2,4,6-trinitrotoluene (TNT) to 2-amino-4,6-dinitrotoluene (2ADNT) and 4-amino-2,6-dinitrotoluene (4ADNT). Elimination rates of metabolically-generated ADNTs are low compared to ADNTs absorbed directly from water, suggesting that metabolically-generated ADNTs may be bound or sequestered within tissue and therefore less available for elimination. A solid phase microextraction (SPME) technique was used to extract ADNTs from T. tubifex tissue to investigate the recalcitrance of metabolically-generated ADNTs. As SPME is a gentle, non-depletive, equilibrium sampling technique useful for measuring "available" organic compounds, we hypothesized that metabolically-generated ADNTs would be less extractable than absorbed ADNTs. T. tubifex were exposed to two scenarios to generate tissues containing absorbed ADNTs and metabolically-generated ADNTs. Tissue was then homogenized in a neutral buffer solution. Polyacrylate-coated (PA) SPME fibers were deployed and agitated in tissue homogenates to measure available ADNTs. Extractability of ADNTs from tissue containing metabolically-generated ADNTs was significantly less than expected: 50-60% based on the theoretical fiber-water partition ratio. Extractability of absorbed ADNTs was significantly higher (81-90%), and not significantly different than expected. The lower SPME extractability of metabolically-generated ADNTs may stem from the unavailability of metabolically-generated ADNTs sequestered in tissue or bound to tissue macromolecules during metabolism of TNT to ADNT. Tissue extractions using SPMEs may be able to estimate bound organic residues in tissue and serve to indicate the toxicological bioavailability of tissue-associated organic compounds.