Rowcover modification of carbon and mineral nutrient partitioning in strawberry (Fragaria ananassa, Duch)

In cool temperature climates where plant growth may be limited by short growing seasons and low temperature stress rowcovers are being used to increase production of fruit and vegetable crops. Two field experiments were conducted to investigate how floating rowcovers applied during autumn, winter and spring affect plant growth and development. The first experiment, 1985-86, examined mineral nutrient and biomass partitioning in a short-day cultivar, \u27Sparkle\u27, and a day-neutral cultivar, \u27Fern\u27, in rowcovered and nonrowcovered plants in autumn. The second experiment, 1986-87 examined carbon, nitrogen and biomass partitioning over time in autumn and in spring and development of yield components for the short-day cultivar \u27Earliglow\u27 in response to an autumn rowcover plus a short-term winter mulch and to no rowcover in autumn plus a long-term winter mulch. In 1985-86 a rowcover in autumn extended the fall growing season by approximately three weeks increasing degree days (base 5\sp\circC) by 63.5. For \u27Sparkle\u27, percents nonstructural carbohydrate and nitrogen in plants were lower and biomass in the canopy was higher under rowcovers than for controls. Differences in mineral nutrients were minor. For \u27Fern\u27 the only difference between treatments was a slightly higher photosynthetic rate for rowcovered plants. Time course studies in 1986-87 indicated that rowcovers in autumn sustained the plant canopy, increased soluble sugar content in leaves and delayed development of leaf morphology typical of plants in rest, but had no effect on partitioning of carbon, nitrogen and biomass in other plant organs. In spring plants in the rowcover plus short-term mulch treatment began growth earlier, had higher levels of metabolizable carbon and a lower percent nitrogen than leaves on control plants. The major effect of the rowcovers plus short-term mulch treatment compared to the no rowcover plus long-term mulch treatment was to increase branch crown mass and earliness of flower emergence. It is concluded that use of rowcovers in autumn and winter plus early removal of winter mulch can significantly enhance development of yield components by sustaining plant growth during autumn and spring

Sensing the framework state and guest molecules in MIL-53(Al) via the electron paramagnetic resonance spectrum of V-IV dopant ions

X-ray diffraction (XRD) and electron paramagnetic resonance spectroscopy (EPR) were combined to study the structural transformations induced by temperature, pressure and air humidity of the "breathing'' metalorganic framework (MOF) MIL-53(Al), doped with paramagnetic V-IV ions, after activation. The correlation between in situ XRD and thermogravimetric analysis measurements showed that upon heating this MOF in air, starting from ambient temperature and pressure, the narrow pore framework first dehydrates and after that makes the transition to a large pore state (lp). The EPR spectra of V-IV=O molecular ions, replacing Al-OH in the structure, also allow to distinguish the as synthesized, hydrated (np-h) and dehydrated narrow pore (np-d), and lp states of MIL-53(Al). A careful analysis of EPR spectra recorded at microwave frequencies between 9.5 and 275 GHz demonstrates that all V-IV=O in the np-d and lp states are equivalent, whereas in the np-h state (at least two) slightly different V-IV=O sites exist. Moreover, the lp MIL-53(Al) framework is accessible to oxygen, leading to a notable broadening of the V-IV=O EPR spectrum at pressures of a few mbar, while such effect is absent for the np-h and np-d states for pressures up to 1 bar

Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.

Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field

The Rivergreenway : utilizing natural resources

There is no abstract available for this creative project.Thesis (M.A.

Subpopulation Characteristics of Egg-Contaminating Salmonella enterica serovar Enteritidis as Defined by the Lipopolysaccharide O Chain

Characterization of Salmonella enterica serovar Enteritidis was refined by incorporating new data from isolates obtained from avian sources, from the spleens of naturally infected mice, and from the United Kingdom into an existing lipopolysaccharide (LPS) O-chain compositional database. From least to greatest, the probability of avian isolates producing high-molecular-mass LPS O chain ranked as follows: pooled kidney, liver, and spleen; intestine; cecum; ovary and oviduct; albumen; yolk; and whole egg. Mouse isolates were most like avian intestinal samples, whereas United Kingdom isolates were most like those from the avian reproductive tract and egg. Non-reproductive tract organ isolates had significant loss of O chain. Isogenic isolates that varied in ability to make biofilm and to be orally invasive produced different O-chain structures at 25°C but not at 37°C. Hens infected at a 91:9 biofilm-positive/-negative colony phenotype ratio yielded only the negative phenotype from eggs. These results indicate that the environment within the hen applies stringent selection pressure on subpopulations of S. enterica serovar Enteritidis at certain points in the infection pathway that ends in egg contamination. The avian cecum, rather than the intestines, is the early interface between the environment and the host that supports emergence of subpopulation diversity. These results suggest that diet and other factors that alter cecal physiology should be investigated as a means to reduce egg contamination