bluuebunny/crossref_metadata_2025_split huggingface dataset:
INHERITANCE OF NUCLEAR 2C DNA CONTENT VARIATION IN INTRASPECIFIC AND INTERSPECIFIC HYBRIDS OF MICROSERIS (ASTERACEAE)
Authors: Price H. James , Chambers Kenton L. , Bachmann Konrad , Riggs Jennifer 
Published: January 2018

Nuclear DNA content varies over 20% within the diploid (2n = 18) species M. douglasii and M. bigelovii. Two different intraspecific crosses were made between M. douglasii biotypes which differed by about 10% in 2C nuclear DNA content. The F2 progeny of one intraspecific cross showed no striking evidence of segregation for DNA content. The mean DNA contents of F2 progeny from two sister hybrids from the second intraspecific cross were significantly different at the 1% level.An interspecific cross was made between biotypes of M. douglasii and M. bigelovii that differed by approximately 10% in DNA amount. The 12 F1 progeny did not cluster around the parental midpoint, but instead encompassed nearly the entire range between the parental means. The five families of F2 progeny studied each had a mean DNA content corresponding to that of the particular F1 from which they were derived, indicating that the F1 plants were not of identical DNA content.The results of this study suggest that DNA sequences which account for the DNA content differences among the plants are unstable and can undergo deletion or amplification in a hybrid. The altered DNA content may be heritably stable and show little or no segregation in the F2 progeny.
STERILITY BARRIERS OF SOME ARTIFICIAL F1 ORCHID HYBRIDS: MALE STERILITY. I. MICROSPOROGENESIS AND POLLEN GERMINATION
Authors: Stort Maria Neysa Silva 
Published: January 2018

Microsporogenesis, pollen germination and fertility of males gametes were studied in 24 artificial intergeneric and interspecific F1 hybrids of orchids. Although parental species had the same chromosome number (2n = 40), microsporogenesis of the hybrids was irregular due to the lack of homology of the chromosomes of the parental species. This led to formation of tetrads of microspores without micronuclei, tetrads with 1–8 micronuclei, triads, dyads with and without micronuclei, and monads. Chromosomes numbers found in haploid microsporocytes ranged from 7 to 40; in micronuclei the chromosome number varied between 1 and 5.In terms of pollen germination, three situations were observed: 1) hybrids whose pollen grains did not germinate in the stigma; 2) hybrids in which the pollen tubes grew down in the style, but did not penetrate into the ovary; 3) hybrids in which the pollen tubes grew down normally through the ovary, reaching the ovules. When the pollen tubes did not penetrate the ovary no fruit was formed. Therefore germination tests carried out in vitro may not indicate pollen fertility, because pollen tube growth in the style of the flower may be insufficient to induce fruit formation or to accomplish fertilization.
THE MEAN INNER RADIUS OF SUN AND SHADE ILEX OPACA LEAVES
Authors: Supnick Martin 
Published: January 2018

The mean inner radius of thickness M, a shape measure defined as the mean of the shortest distances d to the border from all internal points Pi of an object, was applied in its dimensionless form D0M to Ilex opaca sun and shade leaves. This measure has the following attributes: 1) ubiquitous input; 2) the point function f(P) = d is always single valued; 3) it is an intrinsic measure; 4) it is nondirectional; 5) the same definition may be used for any dimension number and be extended to other functions of d.Since Ilex opaca is found in hot, sunny environments, one might predict its sun leaves to be smaller in area and “narrower” in shape (lower D0M) than shade leaves, making them better convective coolers. Although sun leaves of Ilex opaca have been shown to be smaller in area, their D0M was unexpectedly greater than shade leaves.
PHENOTYPIC VARIATION WITHIN “INDIVIDUAL” LICHEN THALLI
Authors: Larson D. W. , Carey C. K. 
Published: January 2018

“Individual” large diam lichen thalli of Umbilicaria vellea (L.) Ach. and U. mammulata (Ach.) Tuck. are not uniform in physiological activity or enzymatic phenotype. Horizontal variation in net photosynthetic rates and dark respiration rates was found, but this was independent of the mass of the photosynthesizing or respiring tissues. In addition, sublethal temperature pretreatments reduced the net photosynthetic and respiratory rates of some areas of the thallus, but increased others.Assays of isoenzyme phenotypes showed that all large diam thalli are extensively polymorphic while young, small diam thalli are mainly monomorphic. Taken together, the results say that the concept of the “individual” may be inappropriate for these organisms.
VARIATION OF STOMATAL DISTRIBUTION IN CAREX AQUATILIS (CYPERACEAE)
Authors: Standley Lisa A. 
Published: January 2018

The density and distribution of stomates in Carex aquatilis Wahl. in the Pacific Northwest were examined using epidermal peels of samples of leaves from natural populations, from greenhouse‐grown transplants and from seedling families grown under controlled conditions. These were compared to stomatal distributions of populations in eastern North America.Populations of Carex aquatilis Wahl. form 2 groups based on the distribution and density of stomates. Carex aquatilis var. dives (Holm) Kükenthal is epistomatic, with adaxial stomatal densities of 28.7–48.5/0.1 mm2. The C. aquatilis var. aquatilis is amphistomatic, with adaxial stomatal densities of 8.1–22.2/0.1 mm2 and abaxial densities of 11.3–24.5/0.1 mm2 in the Pacific Northwest. Total stomatal frequencies are similar in both groups. Stomatal distribution and densities are here shown to not vary significantly within populations and appear to be genetically determined, as shown by progeny tests and growth of seedlings under uniform and experimental conditions. Stomatal distribution in Carex aquatilis appears to be adaptive, and intraspecific variation provides a system for determining the adaptive significance of differences in stomatal patterns.
ARTIFICIAL HYBRIDIZATION OF RUBBER‐BEARING GUAYULE WITH COLD‐TOLERANT PARTHENIUM LIGULATUM
Authors: Hashemi Ahmad , Estilai Ali , West Jan E. , Waines J. Giles 
Published: January 2018

ABSTRACTCaespitose and cold‐tolerant plants of Parthenium ligulatum (Jones) Barneby (Asteraceae) from a native population in the Uinta Basin, Utah, were uprooted, potted, and transferred to a greenhouse in California. Approximately two years after transfer, the plants flowered and subsequently were crossed to diploid guayule (Parthenium argentatum Gray), the rubber‐bearing species, native to the state of Durango, Mexico. Only female guayule × male P. ligulatum crosses produced F1 hybrids. Only crosses involving guayule as female parent and F1 plants as male parents produced backcross (BC,) plants. Hybrid plants were variable with respect to their growth habit, inflorescence, and leaf shape. Both parents and F1 hybrids had 2n = 36 chromosomes. Unlike the parents, however, meiosis was irregular in the hybrids which showed a range of 0–5 and an average of 2.1 univalents at metaphase I. Hybrids averaged 0.87 laggards at anaphase I and 0.83 micronuclei at the tetrad stage. The crossability of guayule and P. ligulatum, the high degree of chromosome pairing of the F1 hybrids, and the production of BC1 plants indicate that the two species are related in spite of their distinct morphological and ecological differences. This study suggests that the cold‐tolerance trait of P. ligulatum may be transferred to guayule through interspecific hybridization followed by backcrossing. The development of cold‐tolerant guayule cultivars is expected to expand the areas of guayule production beyond that of the Chihuahuan desert and similar climates.
PHENOTYPES MEDIATED BY THE IOJAP GENOTYPE IN MAIZE
Authors: Coe Edward H. , Thompson Deborah , Walbot Virginia 
Published: January 2018

The phenotype of maize plants that are homozygous recessive for the nuclear gene iojap is commonly an “anemic,” grainy green appearance accompanied by white leaf stripes, white leaf margins, and reduced growth. In plants in which the iojap effect is occurring (homozygous ij/ij), we find affected tissue varies in extent, from wide, discrete striping to layered striping to short striations; and in distribution, from white leaves to boldly white‐patterned to white‐margined. In homozygous iojap plants the patterns are predictable and are consistent within a particular genetic background.Leaf striping patterns in iojap seedlings and plants are expressed primarily in the leaf margins, in positional patterns that are inconsistent with cellular proliferation. Reversion sectors on iojap plants (green stripes resulting from nuclear reversion of the ij gene), however, follow clonal cell lineages and indicate either that the iojap defects do not arise until after a leaf differentiates, or that they remain correctable in leaf tissue.On transmission through the egg, iojap‐affected plastids become altered to a stable, nongreening state and can be transmitted maternally to subsequent generations. Defects in eggs borne on iojap ears, as revealed by ear maps of seedling progeny, have positional rather than clonal distributions on the ear. The expression of striping nonetheless is clonal in the occasional sectored plants that occur among such maternal progeny. The contrast of maternal sectorials with iojap plants is profound, and shows the period of meiosis and gametogenesis to be a critical passage for plastids in the egg as well as in the pollen.In some genetic backgrounds aborted embryos occur at variable stages in embryo development in ij ij zygotes and in the maternal progeny from ij ij plants. These effects presumably reflect a participation of the organelles in embryogenesis that is subject to the influence of nuclear genes.We conclude that the functional basis of the effects of the iojap gene must be 1) position‐dependent (i.e., dependent on the location of a cell in the meristem or organ at a particular time in development of an organ) and 2) differentiation‐dependent (i.e., dependent on the attainment of a certain state, specific to the genetic background). The iojap phenotype is thus a reflection of developmental progression of the organ rather than cell‐specific, clonal changes. The rate of cell proliferation and growth of one portion of an organ vs. another is related to position‐specific and background‐specific expressions, and the range of iojap expression is similarly related. Maternally inherited sectoring, on the other hand, shows phenotypes that are derived from clonal changes specific to each cell lineage, presumably attributable to sorting of mixed organelles in the apical meristem cells.
Malnutrition Identified by Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition Is Associated With More 30‐Day Readmissions, Greater Hospital Mortality, and Longer Hospital Stays: A Retrospective Analysis of Nutrition Assessment Data in a Major Medical Center
Authors: Hudson Lauren , Chittams Jesse , Griffith Cody , Compher Charlene 
Published: January 2018

AbstractBackgroundFew studies have compared malnutrition identified by the Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition (AND/ASPEN) consensus criteria with clinical outcomes. Our goal was to compare 30‐day readmissions (primary outcome), hospital mortality, length of stay (LOS) in survivors, and time to discharge alive (TDA) in all patients assessed as malnourished or not malnourished using these criteria in fiscal year 2015. We hypothesized more frequent admissions, greater mortality, longer LOS, and less likely shorter TDA in the malnourished patients.MethodsDemographic variables, clinical outcomes, and malnutrition diagnosis for all initial patient admissions were obtained retrospectively from the electronic medical record. Logistic regression was used to compare categorical and Cox proportional hazards for TDA in unadjusted and adjusted (age, sex, race, medical/surgical admission, Charlson Comorbidity Index) models.ResultsOf the 3907 patients referred for nutrition assessment, 66.88% met criteria for moderate or severe malnutrition. Malnourished patients were older (61 vs 58 years, P < .0001), and survivors had longer LOS (15 vs 12 days, P = .0067) and were more likely to be readmitted within 30 days (40% vs 23%, P < .0001). In adjusted models, 30‐day readmissions (odds ratio [OR] 2.13, 95% confidence interval [CI] 1.82–2.48) and hospital mortality (OR 1.47, 95% CI 1.0–1.99) were increased, and the likelihood of earlier TDA was reduced (hazard ratio [HR] 0.55, 95% CI 0.44–0.77) in those who had >2‐day stay.ConclusionThe AND/ASPEN criteria identified malnourished patients in a high‐risk population who had more adverse clinical outcomes. Further studies are needed to determine whether optimal provision of nutrition support can improve these outcomes.
Faecalibacterium prausnitzii and a Prebiotic Protect Intestinal Health in a Mouse Model of Antibiotic and Clostridium difficile Exposure
Authors: Roychowdhury Sanjoy , Cadnum Jennifer , Glueck Bryan , Obrenovich Mark , Donskey Curtis , Cresci Gail A.M. 
Published: January 2018

AbstractBackgroundClostridium difficile (CD) infection (CDI) increases patient morbidity, mortality and healthcare costs. Antibiotic treatment induces gut dysbiosis and is both a major risk factor for CD colonization and treatment of CDI. Probiotics have been trialed to support commensal gut microbiota and reduce CDI. This study investigated commensal microbe Faecalibacterium prausnitzii (FP) and a prebiotic, both known to yield butyrate and be anti‐inflammatory and immunomodulatory, on CD colonization and gut integrity in mice.MethodsMice were randomly grouped and supplemented daily with FP, prebiotic, FP + prebiotic, FP/prebiotic supernatant, or saline throughout the entire study. Following treatment with clindamycin for 3 days, mice were exposed to CD. Feces were collected at baseline, the day after antibiotic, and 1, 3, and 5 days after CD exposure and cultured for bacterial overgrowth and CD colonization. On days 1 and 5 after CD exposure, mice were randomly euthanized, and proximal colon was dissected for histological analysis and preparation of RNA for analysis of proinflammatory and anti‐inflammatory cytokines.ResultsAlthough all mice exhibited bacterial overgrowth and CD colonization, bacterial burden resolved quicker in the FP + prebiotic group. This was associated with induction and resolution of innate immune responses, anion exchanger, and tight junction protein preservation in proximal colon. CD toxin virulence potential was questionable as expression of CD toxin B receptor was depleted in the FP + prebiotic group.ConclusionSupplementation with anti‐inflammatory butyrate‐supporting commensal bacteria and prebiotic may support innate immune responses and minimize bacterial burden and negative effects during antibiotic and CD exposure.
Evaluation of Amazon fruits: chemical and nutritional studies onBorojoa sorbilis
Authors: Rabelo Rodrigues Francimilton , de Souza Ramos Aline , Fernandes Amaral Ana Claudia , Pinto Ferreira José Luiz , da Silva Carneiro Carla , Rocha de Andrade Silva Jefferson 
Published: January 2018

AbstractBACKGROUNDBorojoa sorbilis(Ducke) is an Amazonian species with edible fruits that are widely consumed by the local population, but little studied and not yet economically explored. Thus the aim of this study was to describe the chemical composition, volatile compounds, nutritional aspects and antioxidant activity of the fruit pulp and peel ofB. sorbilis.RESULTSHeadspace solid‐phase microextraction, using polydimethylsiloxane–divinylbenzene (PDMS‐DVB) fiber, resulted in the identification of 59 substances in the pulp and peel ofB. sorbilisfruits after analysis of the chromatograms obtained by gas chromatography–mass spectrometry using polar and nonpolar columns. Esters were the most abundant. Moisture, lipids, protein, dietary fiber, ash, carbohydrate, total energy value, titratable acid, soluble solids and pH were measured. Protein amount, fat content and antioxidant activity were low in both pulp and peel. Carbohydrate content was 179.2 and 134.9 g kg−1in pulp and peel, respectively.CONCLUSIONThis is the first report on the chemical characteristics, flavor and nutritional aspects ofB. sorbilisfruit, which is essential to its economic exploitation. The high energy value associated with the carbohydrate content, plus the low fat content, contribute to a possible use ofB. sorbilisfruits as a food supplement. © 2018 Society of Chemical Industry
The physical limnology of a permanently ice‐covered and chemically stratified Antarctic lake using high resolution spatial data from an autonomous underwater vehicle
Authors: Spigel Robert H. , Priscu John C. , Obryk Maciej K. , Stone William , Doran Peter T. 
Published: January 2018

AbstractWe used an Environmentally Non‐Disturbing Under‐ice Robotic ANtarctic Explorer to make measurements of conductivity and temperature in Lake Bonney, a chemically stratified, permanently ice‐covered Antarctic lake that abuts Taylor Glacier, an outlet glacier from the Polar Plateau. The lake is divided into two lobes – East Lobe Bonney (ELB) and West Lobe Bonney (WLB), each with unique temperature and salinity profiles. Most of our data were collected in November 2009 from WLB to examine the influence of the Taylor Glacier on the structure of the water column. Temperatures adjacent to the glacier face between 20 m and 22 m were 3°C colder than in the rest of WLB, due to latent heat transfer associated with melting of the submerged glacier face and inflow of cold brines that originate beneath the glacier. Melting of the glacier face into the salinity gradient below the chemocline generates a series of nearly horizontal intrusions into WLB that were previously documented in profiles measured with 3 cm vertical resolution in 1990–1991. WLB and ELB are connected by a narrow channel through which water can be exchanged over a shallow sill that controls the position of the chemocline in WLB. A complex exchange flow appears to exist through the narrows, driven by horizontal density gradients and melting at the glacier face. Superimposed on the exchange is a net west‐to‐east flow generated by the higher volume of meltwater inflows to WLB. Both of these processes can be expected to be enhanced in the future as more meltwater is produced.
Avoiding timescale bias in assessments of coastal wetland vertical change
Authors: Breithaupt Joshua L. , Smoak Joseph M. , Byrne Robert H. , Waters Matthew N. , Moyer Ryan P. , Sanders Christian J. 
Published: January 2018

AbstractThere is concern that accelerating sea‐level rise will exceed the vertical growth capacity of coastal‐wetland substrates in many regions by the end of this century. Vertical vulnerability estimates rely on measurements of accretion and/or surface‐elevation‐change derived from soil cores and/or surface elevation tables (SETs). To date there has not been a broad examination of whether the multiple timescales represented by the processes of accretion and elevation change are equally well‐suited for quantifying the trajectories of wetland vertical change in coming decades and centuries. To examine the potential for timescale bias in assessments of vertical change, we compared rates of accretion and surface elevation change using data derived from a review of the literature. In the first approach, average rates of elevation change were compared with timescale‐averaged accretion rates from six regions around the world where sub‐decadal, decadal, centennial, and millennial timescales were represented. Second, to isolate spatial variability, temporal comparisons were made for regionally unique environmental categories within each region. Last, comparisons were made of records from sites where SET‐MH stations and radiometric measurements were co‐located in close proximity. We find that rates vary significantly as a function of measurement timescale and that the pattern and magnitude of variation between timescales are location‐specific. Failure to identify and account for temporal variability in rates will produce biased assessments of the vertical change capacity of coastal wetlands. Robust vulnerability assessments should combine accretion rates from multiple timescales with the longest available SET record to provide long‐term context for ongoing monitoring observations and projections.
Characterization and Finite Element Analysis of the Tensile Behavior of Electrospun Polymer Single Fibers
Authors: Ma Shuaijiang , Wang Shiwei , Leng Yuting , Li Qian , Hu Guo‐Hua 
Published: January 2018

AbstractIn this paper, polymer single fibers are prepared by electro‐spinning technology with different solvent rations, and the micromechanics properties are investigated together with the finite element analysis. It is found that the tensile stress–strain curves of single fibers can be attributed to two kinds of trends, which are independent of the solvent ratios. A possible arrangement model of polymer chains within the electrospun fibers is proposed according to the tensile stress–strain curves and the mechanics theories. The effect of polymer chains arrangement on the mechanical properties of the fibers is explored by the finite element analysis. This research shows a practical reference to predict the relationship between orientation degree of polymer chains and mechanical properties within the fibers.
Initial evaluation of Advanced Collapsed cone Engine dose calculations in water medium for I‐125 seeds and COMS eye plaques
Authors: Morrison Hali , Menon Geetha , Larocque Matthew P. , van Veelen Bob , Niatsetski Yury , Weis Ezekiel , Sloboda Ron S. 
Published: January 2018

PurposeTo investigate the dose calculation accuracy in water medium of the Advanced Collapsed cone Engine (ACE) for three sizes of COMS eye plaques loaded with low‐energy I‐125 seeds.MethodsA model of the Oncura 6711 I‐125 seed was created for use with ACE in Oncentra® Brachy (OcB) using primary‐scatter separated (PSS) point dose kernel and Task Group (TG) 43 datasets. COMS eye plaque models of diameters 12, 16, and 20 mm were introduced into the OcB applicator library based on 3D CAD drawings of the plaques and Silastic inserts. To perform TG‐186 level 1 commissioning, treatment plans were created in OcB for a single source in water and for each COMS plaque in water for two scenarios: with only one centrally loaded seed, or with all seed positions loaded. ACE dose calculations were performed in high accuracy mode with a 0.5 × 0.5 × 0.5 mm3 calculation grid. The resulting dose data were evaluated against Monte Carlo (MC) calculated doses obtained with MCNP6, using both local and global percent differences.ResultsACE doses around the source for the single seed in water agreed with MC doses on average within < 5% inside a 6 × 6 × 6 cm3 region, and within < 1.5% inside a 2 × 2 × 2 cm3 region. The PSS data were generated at a higher resolution within 2 cm from the source, resulting in this improved agreement closer to the source due to fewer approximations in the ACE dose calculation. Average differences in both investigated plaque loading patterns in front of the plaques and on the plaque central axes were ≤ 2.5%, though larger differences (up to 12%) were found near the plaque lip.ConclusionsOverall, good agreement was found between ACE and MC dose calculations for a single I‐125 seed and in front of the COMS plaques in water. More complex scenarios need to be investigated to determine how well ACE handles heterogeneous patient materials.