bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Micronutrient Fortification on Nutritional and Other Properties of Nixtamal Tortillas
Authors: Burton K. E. , Steele F. M. , Jefferies L. , Pike O. A. , Dunn M. L. 
Published: March 2008

ABSTRACTNixtamalization is the process of steeping dried corn in hot water with calcium hydroxide (lime) with subsequent removal of all or most of the pericarp through washing. The resulting product is called nixtamal. Approximately 60% of corn tortillas in Mexico are produced from nixtamal, with the remainder prepared from nixtamalized corn flour. Nixtamal was fortified with micronutrient premix containing iron, zinc, folic acid, niacin, riboflavin, and thiamin. Premix composition followed a proposed Mexican regulation for corn flour fortification, adjusted for moisture. Effects of premix on masa adhesiveness, hardness, and pH, as well as tortilla sensory properties, stretchability, rollability, and color were measured. Micronutrient levels were tested in the dry corn, nixtamal, masa, and tortillas. There were no significant differences in masa texture or pH, tortilla rollability, or consumer acceptance of tortillas when comparing unfortified control and fortified treatments. Added thiamin was almost entirely degraded during processing. Folic acid and riboflavin decreased 26 and 45%, respectively, through the masa‐tortilla manufacturing process. Niacin showed no significant loss. Despite processing losses, fortification resulted in significant nutrient increases compared with control tortillas. Folic acid increased 974%, riboflavin increased 300%, niacin increased 141%, iron increased 156%, and zinc increased 153% in fortified tortillas.
Extraction and Physicochemical Characterization of Rye β‐Glucan and Effects of Barium on Polysaccharide Molecular Weight
Authors: Brummer Yolanda , Jones Sandra , Tosh Susan M. , Wood Peter J. 
Published: March 2008

ABSTRACTUse of saturated Ba(OH)2 to extract rye β‐glucan led to a depolymerized product. Similar depolymerization of β‐glucan was observed when oat bran was extracted with this reagent. Isolated oat β‐glucan, detarium xyloglucan, guar galactomannan, and wheat and rye arabinoxylan were also depolymerized by treatment with the barium reagent. The degree of depolymerization was related to time of contact with, and concentration of, the barium. Rye β‐glucan of two different molecular weights (MW) were isolated and characterized. The structure of rye β‐glucan, as evaluated from the ratio of (1→3)‐linked cellotriosyl to (1→3)‐linked cellotetraosyl primary structural units, most closely resembles barley β‐glucan. Analytical variability of this ratio is discussed. A freshly prepared solution (2%) of the higher MW sample showed shear thinning behavior typical of cereal β‐glucans. The lower MW sample at 2% was not shear thinning, but on further purification, after storage for seven days, a 6% solution had gelled as shown by the mechanical spectrum.
Improved Isolation of Zein from Corn Gluten Meal Using Acetic Acid and Isolate Characterization as Solvent
Authors: Selling Gordon W. , Woods Kristen Kruger 
Published: March 2008

ABSTRACTAn improved means of isolating zein is needed to develop new uses for corn zein. We have measured the yield of zein and evaluated the ability of acetic acid to remove zein from corn gluten meal, distillers dried grains, and ground corn using acetic acid as solvent. Acetic acid removed zein more quickly, at lower temperatures, and in higher yields when compared with alcoholic solvents. After 60 min at 25°C, ≈50% of the zein in corn gluten meal was removed. A step change in yield from 43 to 50% occurs as the extraction temperature is increased from 40 to 55°C after mixing for 30 min at 25% solids. The protein composition of the zein removed from corn gluten meal using acetic acid is very similar to that of commercial zein by SDS‐PAGE. The zein obtained from corn gluten meal using acetic acid had higher amounts of fatty acids and esters according to IR analysis, leading to slightly lower protein content. Films made from zein extracted from corn gluten meal using acetic acid had lower tensile strength (≈60% lower) than films produced from commercial zein. Fibers with very small diameter (0.4–1.6 μm) can be produced by electrospinning using the AcOH solution obtained after corn gluten meal extraction.
Laboratory Wet Milling of Corn: Milling Fraction Correlations and Variations Among Crop Years
Authors: Arora Amit , Niu Yuxian , Tumbleson M. E. , Rausch Kent D. 
Published: March 2008

ABSTRACTSeveral coproducts result from fractionating corn in the wet‐milling process. Because small changes in product composition and milling characteristics can have a major impact on coproduct yields and values, testing is done to anticipate final product yields. Using small sample size and controlled conditions, a laboratory wet‐milling method proved to be a useful tool for wet milling and genetics industries. A wet‐milling process (100‐g batches) was used for data collection. Data collected during 11 years (1994–2004) were observed for samples used as benchmarks to verify process precision and accuracy and determine correlations among wet‐milling yields. More than 400 milling tests were performed on benchmark samples. Data from benchmark samples also were pooled. Coefficients of variation were low (<6%) for mean yields; year‐to‐year standard deviations of benchmark sample yield means were homogenous and implied precision of the procedure. Some differences were detected in mean yields among years (P ≤ 0.05) for benchmark data due to combined effects of hybrid and environment. A negative correlation (r = –0.58) was observed between starch and gluten yield for pooled benchmark data. Four years (2002–2005) of milling data from commercially available hybrids were analyzed using the milling procedure. For pooled commercial data, the correlation between starch and fiber yield was (r = –0.80); correlation between starch and gluten was (r = –0.76).
Empirical Modeling of Mean Residence Time in a Co‐Rotating Twin‐Screw Extruder with Rice Flour
Authors: Lei Hanwu , Fulcher R. Gary , Ruan Roger , van Lengerich Bernhard 
Published: March 2008

ABSTRACTMean residence time of rice flour in a twin‐screw extruder was determined using a blue tracer. Variables studied included moisture content, screw speed, barrel temperature, and screw configuration. Mean residence time increased with the increase of the barrel temperature and with the addition of reverse and kneading elements. Mean residence time was significantly related to screw speed, moisture content, die pressure, and screw configuration (P < 0.05). An empirical model was developed to predict mean residence time with the ability to reflect the changes of the barrel temperature and screw configuration. The effects of different extrusion operating conditions including screw speed, moisture content, barrel temperature, and screw geometry on the mean residence time were considered in the model. The validity of the developed model was extensively evaluated and verified using different screw geometries and other processing variables. The mean residence times predicted by the developed model are in good agreement with the experimental data.
Tocopherols, Tocotrienols, and γ‐Oryzanol Contents in Japonica and Indica Subspecies of Rice (Oryza sativa L.) Cultivated in Brazil
Authors: Heinemann Riana J. B. , Xu Zhimin , Godber J. Samuel , Lanfer‐Marquez Ursula M. 
Published: March 2008

ABSTRACTWhole rice contains several fat‐soluble phytochemicals such as tocopherols, tocotrienols, and γ‐oryzanol which have been reported to possess beneficial health properties. This study was conducted to determine whether brown rice belonging to indica and japonica subspecies were distinguishable from each other regarding the concentration of these compounds by analyzing 32 genotypes. The fat‐soluble compounds were analyzed by normal‐phase HPLC in a single run. The variability of the compounds analyzed was high, but the mean content of γ‐oryzanol across all samples was significantly higher (P < 0.01) in japonica (246.3 mg/kg) than in indica rice (190.1 mg/kg). Similar differences were found for total vitamin E contents which were 24.2 mg/kg in japonica and 17.1 mg/kg in indica rice, respectively. In japonica rice, α‐tocopherol, α‐tocotrienol, and γ‐tocotrienol were the most abundant homologs, while in indica rice the most abundant were γ‐tocotrienol, α‐tocopherol, and α‐tocotrienol. A significant Pearson coefficient (0.80, P < 0.001) between α‐tocopherol and α‐tocotrienol levels was found, independent of the subspecies. Both compounds were positively correlated to total tocols and γ‐oryzanol contents. Although more studies are needed to evaluate the interference of growing rice in different environments and multiple years, the present study provided information on natural variations of the vitamin E isomers and the γ‐oryzanol contents in different rice genotypes.
Molecular characterization of the bovine chromodomain Y‐like genes
Authors: Wang A. , Yasue H. , Li L. , Takashima M. , Ponce de León F. A. , Liu W.‐S. 
Published: March 2008

SummaryThe human chromodomain protein, Y‐like (CDYL) gene family consists of three members, one on the Y chromosome (CDY) and two on autosomes (CDYL and CDYL2). Studies in the human and mouse showed that genes in the CDYL family are abundantly expressed in testis and play an important role in spermatogenesis. In this study, we have characterized the bovine CDYL (bCDYL) and CDYL2 (bCDYL2) genes. We found that bCDYL and bCDYL2 are very similar to the human orthologues at both mRNA (79% and 85%) and protein (89% and 93%) levels. However, the similarity between the bCDYL and bCDYL2 proteins is low (41%). The bCDYL gene is composed of nine exons, and the bCDYL2 has seven exons. The bCDYL and bCDYL2 genes were mapped by radiation hybrid mapping to bovine chromosomes (BTA) 24 and 18 respectively. The bCDYL gene has four transcript variants that produce four protein isoforms. RT‐PCR expression analysis in 12 bovine tissues showed that bCDYL variant 2 was expressed in the testis only, bCDYL variants 1, 3 and 4 were expressed predominantly in the testis and at very low or undetectable levels in the remaining tissues and bCDYL2 was expressed ubiquitously. Examination of bovine testis with in situ hybridization revealed that the bCDYL and bCDYL2 transcripts were found mainly in spermatids, though the amounts of transcripts varied among genes/variants. In addition, antisense transcripts were detected in bCDYL variants 2/3 and 4, as well as in the bCDYL2 gene.
Transcriptional analysis of host responses to Marek’s disease virus infection in genetically resistant and susceptible chickens
Authors: Sarson A. J. , Parvizi P. , Lepp D. , Quinton M. , Sharif S. 
Published: March 2008

SummaryMarek’s disease virus (MDV) is a cell‐associated oncogenic herpesvirus that targets B cells and T cells, inducing lymphoid tumours in chickens. Genetic resistance to Marek’s disease (MD) is regulated in a polygenic fashion. In this study, we sought to compare the gene expression profiles following infection of birds that are genetically resistant or susceptible to MD (with the B21 and B19 haplotypes respectively at the MHC locus), including comparisons to uninfected controls. On days 4, 7, 14 and 21 post‐infection, gene expression profiles in spleen tissue were obtained using a chicken immune‐specific microarray. A number of genes showed significant (P ≤ 0.05) differential expression across time and treatments. These included the chemokine AH221, B‐cell marker Bu‐1, IgG, IgA, IgM, MHC class II β chain, granzyme A (GZMA) and signal transducers and activators of transcription 2 (STAT2) genes. In several comparisons, genes such as GZMA and STAT2 were induced in infected birds regardless of their genetic background. However, only immunoglobulin genes were differentially expressed by ≥2‐fold in resistant compared with susceptible infected chickens. IgM and IgG were significantly induced on day 7 post‐infection in susceptible chickens compared to resistant birds, whereas both of these genes were repressed in susceptible birds on day 14 post‐infection. Overall, gene expression profiles in the chicken spleen observed after MDV infection were dependent on time and host genetic background. These gene expression profiles provide a platform for defining novel candidate genes for resistance or susceptibility to MD.
Associations of plasma pro‐inflammatory cytokines, fibrinogen, viscosity and C‐reactive protein with cardiovascular risk factors and social deprivation: the fourth Glasgow MONICA study
Authors: Welsh Paul , Woodward Mark , Rumley Ann , Lowe Gordon 
Published: March 2008

SummaryCirculating inflammatory markers [plasma fibrinogen, viscosity and C‐reactive protein (CRP)] have been associated with cardiovascular risk factors. In part, these associations may reflect ‘upstream’ changes in pro‐inflammatory cytokines – interleukin (IL)‐6, IL‐18 and tumour necrosis factor (TNF)α. These variables were measured in 1666 men and women aged 25–64 years and their associations with risk factors were studied. All six markers increased significantly with age. IL‐18 and TNFα levels were higher, and fibrinogen levels lower, in males. Oral contraceptive use increased levels of CRP, whilst postmenopausal women had elevated IL‐18 levels. Inflammatory markers were also associated with components of the metabolic syndrome. Most inflammatory markers showed an increasing trend with alcohol consumption in men and a decreasing trend in women, and increasing trends with level of smoking. Inflammatory markers generally showed strong positive associations with social deprivation. After adjustment for classical risk factors, IL‐6, IL‐18 and TNFα retained significant associations with social deprivation only in men (P < 0·008). We conclude that pro‐inflammatory cytokines are associated with several cardiovascular risk factors including social deprivation, and may mediate some of their associations with ‘downstream’ inflammatory markers (fibrinogen, viscosity and CRP).
Vitamin D deficiency, cardiac iron and cardiac function in thalassaemia major
Authors: Wood John C. , Claster Susan , Carson Susan , Menteer J. D. , Hofstra Thomas , Khanna Rachna , Coates Thomas 
Published: March 2008

SummaryVitamin D25‐OH and D1‐25OH levels were compared with cardiac R2* (1/T2*), left ventricular ejection fraction (LVEF), age, ferritin and liver iron in 24 thalassaemia major patients. Vitamin D25‐OH levels were reduced in 13/24 patients while vitamin D1‐25OH levels were often elevated. Vitamin D25‐OH levels decreased with age (r2 = 0·48) and with liver iron (r2 = 0·20). Cardiac R2* was inversely related with the ratio of D25‐OH to D1‐25OH levels (r2 = 0·42). LVEF was also proportional to the D25‐OH/D1‐25OH ratio (r2 = 0·49). Vitamin D deficiency may be associated with cardiac iron uptake and ventricular dysfunction in thalassaemia major patients.
Process‐based model for direct and indirect effects of hydrographic conditions on Central Baltic cod (Gadus morhua) egg mortality
Authors: ANDERSEN K. H. , MÖLLMANN C. , KÖSTER F.W. 
Published: March 2008

AbstractA process‐oriented model for the mortality of eggs of cod Gadus morhua in the Central Baltic Sea is developed, based on a synthesis of existing knowledge of the effects of salinity, oxygen and predation by sprat Sprattus sprattus. The models show the importance of the vertical and temporal overlap between eggs and predations. Effects related to the changing buoyancy of the eggs due to age and size of the mother fish, batch number and stock structure are not of major importance for the egg survival of this stock. It is demonstrated that under the present high sprat predation pressure, the observed delay in spawning time has increased egg survival.
Vertical distributions of Japanese sardine (Sardinops melanostictus) eggs: comparison of observations and a wind‐forced Lagrangian mixing model
Authors: TANAKA YUJI , FRANKS PETER J. S. 
Published: March 2008

AbstractTo understand how Japanese sardine eggs vertically disperse in water, we acquired a series of depth‐resolved samples of eggs while tracking a drogued buoy to follow the water mass in which the eggs were spawned. This survey was conducted in early March of 1991, when the sardine population was abundant and actively spawning in the Pacific off Kyushu. Buoyancy of the eggs was estimated by measuring the specific gravity, and was 1–4 × 10−3 less than that of the water in which they were spawned, giving a rising speed of 1–2 mm s−1. In an attempt to diagnose the dynamics underlying the observed vertical profiles of the eggs, a one‐dimensional egg distribution model incorporating the egg rising speed and wind‐ and depth‐dependent vertical diffusivity was formulated. Observed eggs were mainly in the surface mixed layer, and their vertical distribution changed with wind‐induced surface mixing: during strong winds, the eggs were distributed relatively evenly over the upper 60–75 m, whereas during weak winds and shallow pycnocline, the eggs formed a subsurface peak around 25 m depth. The model accurately reproduced these variations in the vertical distributions of eggs, suggesting that the gradients of egg concentration are sensitive to the strength of wind and the structure of underlying hydrography. Further tests with the model showed the importance of positive buoyancy: neutrally buoyant eggs formed subsurface maxima below the food‐rich euphotic zone. The balance of vertical mixing and floating, which allows the eggs to remain in the euphotic zone but away from the near‐surface waters, may be an adaptation to minimize surface‐enhanced predation, while allowing the eggs to hatch in the food‐rich euphotic zone.
Relationships between oceanic conditions and growth of Chinook salmon (Oncorhynchus tshawytscha) from California, Washington, and Alaska, USA
Authors: WELLS BRIAN K. , GRIMES CHURCHILL B. , SNEVA JOHN G. , McPHERSON SCOTT , WALDVOGEL JAMES B. 
Published: March 2008

AbstractWe model age‐specific growth rates of Chinook salmon (Oncorhynchus tshawytscha) with two life‐history behaviors from Alaska (i. Situk and ii.Taku Rivers), Puget Sound, Washington (iii., iv. Skagit River), and California (v. Smith River) relative to oceanic conditions in those regions. By analyzing over 20 yr of biological and physical data from the NE Pacific downwelling, upwelling, and transition zones, we are able to determine the factors affecting growth across much of the species’ range and between life‐history behaviors. With scale increment data from returning fish, we use path analysis and partial least squares regression to quantify the relationships between growth and regional‐ and large‐scale oceanic conditions (e.g., sea level height, sea surface temperature, upwelling). Alaskan fish with both ocean‐ and stream‐type behaviors were fit best by the environmental data from the winter in Alaska waters. Specifically, coastal and gyre factors such as sea surface temperature, river flow, and Ekman pumping positively correlated to growth, indicating a productive and strong Alaska Current promoted growth. Growth of fish from California was fit by local factors such as increased upwelling, lower coastal sea surface temperature, and wind stresses during summer and spring, indicating a productive and strong California Current promoted growth. For Puget Sound, Washington, growth of fish that migrate to sea in their first year was generally negatively correlated to a strong California Current. Puget Sound fish that spend a year in freshwater before migrating to sea were modeled well with environmental data from their source region for the first 2 yr at sea and by data from Alaska waters in their third year at sea. Results suggest that conditions in which the transition zone is dominated by neither the Alaska nor California Currents are best for increased growth of Puget Sound fish.
Effects of three stressors on vegetation in an oligohaline marsh
Authors: SLOCUM MATTHEW G. , MENDELSSOHN IRVING A. 
Published: March 2008

Summary1. When multiple stressors have interactive effects they can lead to important changes in ecosystem function. We examined how three stressors affected the plant community in an oligohaline marsh in southeastern Louisiana, U.S.A. These stressors included herbivory (mostly by the introduced rodent Myocastor coypus), disturbance (herbicide application) and nutrient enrichment (three levels of N–P–K fertilizer). Sampling was conducted six times over 4 years.2. Recovery after disturbance was slow, such that after 26 months biomass in disturbed plots was 36% that of controls. Slow recovery appeared to be due to herbivory, as exclusion of herbivores for 14 months led to much more biomass compared to non‐excluded plots. Exclusion did not, however, aid recovery of species richness; this recovery required 51 months in total.3. Nutrient enrichment increased biomass by 41% and decreased species richness by c. 20% in later sampling periods. Decreased species richness was due primarily to a reduced ability of dominant species to co‐exist (as determined with Hill’s diversity number N1). Nutrient enrichment did not interact with the other treatments.4. Disturbance favoured two grasses (Echinochloa crus‐galli and Leptochloa fascicularis), while lack of disturbance favoured two herbs (Sagittaria lancifolia and Polygonum punctatum) and two vines (Ipomoea sagittata and Cuscuta pentagona). Nutrient enrichment positively affected abundance of two species (C. pentagona and L. fascicularis). Herbivory did not affect species composition.5. The effect of one stressor (experimental disturbance) on plant biomass depended on the strength of another stressor (herbivory). Nutrient enrichment was also important in affecting the plant community, but only as a single stressor. All effects changed over time, and it was clear that to understand properly the effects of multiple stressors, long‐term, manipulative field experiments are necessary.
Carbon allocation in boreal black spruce forests across regions varying in soil temperature and precipitation
Authors: VOGEL JASON G. , BOND‐LAMBERTY BEN P. , SCHUUR EDWARD A. G. , GOWER STITH T. , MACK MICHELLE C. , O'CONNELL KARI E. B. , VALENTINE DAVID W. , RUESS ROGER W. 
Published: March 2008

AbstractA common hypothesis for northern ecosystems is that low soil temperatures inhibit plant productivity. To address this hypothesis, we reviewed how separate components of ecosystem carbon (C) cycling varied along a soil temperature gradient for nine well‐drained, relatively productive boreal black spruce (Picea mariana Mill. [B.S.P.]) forests in Alaska, USA, and Saskatchewan and Manitoba, Canada. Annual soil temperature [expressed as soil summed degree days (SDD)] was positively correlated with aboveground net primary productivity (ANPP), while negatively correlated with total belowground carbon flux (TBCF). The partitioning of C to ANPP at the expense of root processes represented a nearly 1 : 1 tradeoff across the soil temperature gradient, which implied that the amount of C cycling through these black spruce ecosystems was relatively insensitive to variation in SDD. Moreover, the rate at which C accumulated in the ecosystem since the last stand replacing fire was unrelated to SDD, but SDD was positively correlated to the ratio of spruce‐biomass : forest‐floor‐mass. Thus, plant partitioning of C and the distribution of ecosystem C were apparently affected by soil temperature, although across regions, precipitation co‐varied with soil temperature. These two factors likely correlated with one another because of precipitation's influence on soil heat balance, suggesting that a soil temperature–precipitation interaction could be responsible for the shifts in C allocation. Nonetheless, our results highlight that for this boreal ecosystem, ANPP and TBCF can be negatively correlated. In tropical and temperate forests, TBCF and ANPP have been reported as positively correlated, and our results may reflect the unique interactions between soil temperature, forest floor accumulation, rooting depth, and nutrient availability that characterize the black spruce forest type.