A coherent perfect absorber exploits the interferometric nature of light to deposit all of a light field's incident energy into an otherwise weakly absorbing sample. The downside of this concept is that the necessary destructive interference in coherent perfect absorbers gets easily destroyed both by spectrally or spatially detuning the incoming light field. Each of these two limitations has recently been overcome by insights from exceptional-point physics and by using a degenerate cavity, respectively.
View Article and Find Full Text PDFPollution by nanoplastic is a growing environmental and health concern. Currently the extent of nanoplastic in the environment can only be cumbersomely and indirectly estimated but not measured. To be able to quantify the extent of the problem, detection methods that can identify nanoplastic particles that are smaller than 1 [Formula: see text]m are critically needed.
View Article and Find Full Text PDFOne of the key insights of non-Hermitian photonics is that well-established concepts such as the laser can be operated in reverse to realize a coherent perfect absorber (CPA). Although conceptually appealing, such CPAs are limited so far to a single, judiciously shaped wavefront or mode. Here, we demonstrate how this limitation can be overcome by time-reversing a degenerate cavity laser based on a unique cavity that self-images any incident light field onto itself.
View Article and Find Full Text PDFNectar is a primary reward mediating plant-animal mutualisms to improve plant fitness and reproductive success. Four distinct trichomatic nectaries develop in cotton (Gossypium hirsutum), one floral and three extrafloral, and the nectars they secrete serve different purposes. Floral nectar attracts bees for promoting pollination, while extrafloral nectar attracts predatory insects as a means of indirect protection from herbivores.
View Article and Find Full Text PDFCarbon-calcium inclusions (CCaI) either as calcium oxalate crystals (CaOx) or amorphous calcium carbonate cystoliths are spread among most photosynthetic organisms. They represent dynamic structures with a significant construction cost and their appearance during evolution indicates an ancient origin. Both types of inclusions share some similar functional characteristics providing adaptive advantages such as the regulation of Ca levels, and the release of CO and water molecules upon decomposition.
View Article and Find Full Text PDFThe unfolded protein response (UPR) is activated by various stresses during vegetative development in Arabidopsis, but is constitutively active in anthers of unstressed plants. To understand the role of the UPR during reproductive development, we analyzed a double mutant, ire1a ire1b. The double mutant knocks out the RNA-splicing arm of the UPR signaling pathway.
View Article and Find Full Text PDFClavibacter michiganensis subsp. nebraskensis causes Goss's bacterial wilt and blight on maize and is managed primarily with C. michiganensis subsp.
View Article and Find Full Text PDFJ Agric Food Chem
November 2015
A study of yolks stored up to 168 d at -20 °C was conducted to determine the gelation behavior and mechanism of freeze-thawed yolk. Methods used were rheology, native and sodium dodecyl sulfate polyacrylamide gel electrophoresis (native- and SDS-PAGE), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), particle size analysis, and proton nuclear magnetic resonance ((1)H NMR) spectroscopy for matrix mobility. Results indicate that both constituents of plasma and granules contributed to gelation of yolk under freezing.
View Article and Find Full Text PDFCalcium oxalate crystals in higher plants occur in five major forms namely raphides, styloids, prisms, druses and crystal sand. The form, shape and occurrence of calcium oxalate crystals in plants are species- and tissue-specific, hence the presence or absence of a particular type of crystal can be used as a taxonomic character. So far, four different types of needle-like raphide crystals have been reported in plants.
View Article and Find Full Text PDFIn soybean, genic male sterility can be utilized as a tool to develop hybrid seed. Several male-sterile, female-fertile mutants have been identified in soybean. The male-sterile, female-fertile ms5 mutant was selected after fast neutron irradiation.
View Article and Find Full Text PDFPremise Of The Study: This is the first large-scale study comparing leaf crystal macropatterns of the species-rich sister genera Piper and Peperomia. It focuses on identifying types of calcium oxalate crystals and their macropatterns in leaves of both genera. The Piper results are placed in a phylogenetic context to show evolutionary patterns.
View Article and Find Full Text PDFBackground And Aims: Leaves of succulent Peperomia obtusifolia (Piperaceae), and its related species, contain a large multilayered hypodermis (epidermis) subtended by a very small single-layered photosynthetic palisade parenchyma, the latter containing spherical aggregates of crystals called druses. Each druse is in a central vacuole surrounded by chloroplasts. All hypodermal cell walls are thin, except for thick lowermost periclinal walls associated with the upper periclinal walls of the subtending palisade cells.
View Article and Find Full Text PDFPremise Of The Study: This basic study may help plant biologists better understand the variety and occurrence of crystal forms and their function in plants. Literature records hold four examples of two different crystal types in one cell. One, unillustrated report mentions druses and crystal sand from one species of tribe Naucleeae (Rubiaceae) and "occasional occurrences" in additional unnamed taxa.
View Article and Find Full Text PDFBispecific scFv antibody-derivatives (bsscFvs) recruiting natural killer (NK) cells for the lysis of malignant cells have therapeutic potential. However, a bsscFv specific for the B-lymphoid tumor antigen CD19 and the trigger molecule CD16 on NK cells had similar affinities for both antigens (42 and 58nM, respectively) and was not optimal for cytotoxicity. Therefore, a bispecific tribody (bsTb) was constructed with two binding sites for CD19 and one for CD16.
View Article and Find Full Text PDFBispecific Abs offer new perspectives for cancer immunotherapy. In this study, we describe a recombinant bispecific single-chain fragment variable (bsscFv) directed against Fc alpha RI (CD89) on polymorphonuclear neutrophils (PMNs) or monocytes/macrophages and HLA class II on lymphoma target cells. Fc alpha RI and HLA class II-directed single-chain fragment variable (scFv) fragments were isolated from phage display libraries, established from the hybridomas A77 and F3.
View Article and Find Full Text PDFAb-dependent polymorphonuclear granulocyte (PMN)-mediated cytotoxicity may play an important role in the control of malignant diseases. However, little is known as to which particular pathways are used for the killing of malignant cells by PMN. The production of reactive oxygen intermediates (ROI) has been observed to occur during Ab-dependent, cell-mediated cytotoxicity (ADCC).
View Article and Find Full Text PDFTobacco floral nectaries undergo changes in form and function. As nectaries change from green to orange, a new pigment is expressed. Analysis demonstrated that it is β-carotene.
View Article and Find Full Text PDFNeutral (storage) oil bodies occur in leaf mesophyll cells of many angiosperms, but their literature has been largely forgotten. We review this literature and provide a survey of 302 species and hybrids from mostly north-central US species representing 113 families. Freehand cross sections of fresh leaves stained with Sudan IV verified the presence of oil.
View Article and Find Full Text PDFHydrogen peroxide produced from the nectar redox cycle was shown to be a major factor contributing to inhibition of most microbial growth in floral nectar; however, this obstacle can be overcome by the floral pathogen Erwinia amylovora. To identify the source of superoxide that leads to hydrogen peroxide accumulation in nectary tissues, nectaries were stained with nitroblue tetrazolium. Superoxide production was localized near nectary pores and inhibited by diphenylene iodonium but not by cyanide or azide, suggesting that NAD(P)H oxidase is the source of superoxide.
View Article and Find Full Text PDFBackground And Aims: Prunus, subgenus Padus, exhibits two completely different calcium oxalate crystal macropatterns in mature leaves. Foliar macropattern development has been described previously in P. virginiana, representing one version.
View Article and Find Full Text PDFOxalate crystals are very common in angiosperms, but few descriptions of their macropattern (crystal types, their tissue distribution, and development) exist. Because unusually large prismatic crystals and druses, are known from pomegranate, we traced the development of crystal macropattern in various-aged leaf samples from a living plant and from herbarium specimens using unstained whole mounts (some bleached and cleared), stained leaf samples, and leaf and stem cross sections. Preparations were viewed with bright-field light microscopy and with crossed polarizers.
View Article and Find Full Text PDFThis study analyzed soybean seeds from 116 cultivars for total, insoluble, and soluble oxalate (Ox), phytate (InsP6), calcium (Ca), and magnesium (Mg) because of their potential beneficial or harmful effects on human nutrition. These cultivars were divided into four groups (A-D) on the basis of the year and geographic location where they were grown. Oxalate concentration ranged from about 82 to 285 mg/100 g of dry seed.
View Article and Find Full Text PDFThe consumption of foods made from soybeans is increasing because of their desirable nutritional value. However, some soy foods contain high concentrations of oxalate and/or phytate. Oxalate is a component of calcium oxalate kidney stones, whereas phytate is an inhibitor of calcium kidney stone formation.
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