bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microplot Size and Retainer Effects on Rice Growth and Nitrogen‐15 Accumulation
Authors: Bufogle Arthur , Bollich Patrick K. , Kovar John L. , Lindau Charles W. , Macchiavelli R. E. 
Published: July 2010

AbstractNitrogen studies on flooded rice (Oryza sativa L.) often use 15N as a tracer, which is usually contained within microplots and retainers to restrict root growth and to prevent 15N movement in floodwater and the soil solution. Little research has addressed the effects of the microplot and retainer on plant growth, N accumulation, and plot microclimate. The objectives of this field study were to (i) determine the effects of microplot size and retainer on plant growth, N accumulation, floodwater and soil temperature, and floodwater and soil pH and (ii) determine the size of microplots with and without retainers that most closely simulate a field plot. ‘Cypress’ rice was drill‐seeded in a Crowley silt loam soil (fine, smectitic, thermic Typic Albaqualf) in circular microplots (15, 35, and 60 cm in diameter) with retainers, and square microplots (75 cm long) with and without retainers. Nitrogen‐15‐labeled urea was applied preflood at 151 kg N ha−1. The control was a 2.1‐ by 7.6‐m field plot fertilized with unlabeled urea at 151 kg N ha−1. All plots were harvested at 90% heading. Plants in 15‐, 35‐, and 60‐cm microplots were 8.5 to 25.4 cm shorter than plants in the field plot in at least one year. Plant dry matter and total N accumulation in microplots did not differ from the field plot, except for total N accumulation in the 15‐cm microplot and dry matter in the 35‐cm microplot. Water and soil temperature in microplots with retainers were 1.0 to 3.5°C lower than in the field plot. Water and soil pH did not differ between microplots and the field plot. The 75‐cm square microplot with a retainer was found to be the best substitute for the field plot.
Supplemental Ultraviolet‐B Radiation Does Not Reduce Growth or Grain Yield in Rice
Authors: Dai Qiujie , Peng Shaobing , Chavez Arlene Q. , Miranda Ma. Lourdes L. , Vergara Benito S. , Olszyk David M. 
Published: July 2010

AbstractNegative effects of enhanced UV‐B radiation have been demonstrated in plants, but impacts under realistic field conditions remain uncertain. Adverse impacts to major crops, such as rice (Oryza sativa L.), that are grown in areas with currently high ambient levels of UV‐B, could have consequences for food security. To address the response of rice to UV‐B, we conducted an intensive and extensive series of field experiments from 1992 to 1995 documenting the effects of supplemental UV‐B (simulating approximately 20% ozone depletion for the Philippines), using irrigated rice cultivars under tropical conditions. This multiseason study indicated that supplemental UV‐B had no significant effects on rice grain yield (including the yield components spikelet filling percentage, and 1000‐grain weight) or growth parameters (plant height or panicles per square meter). The absence of UV‐B effects was consistent across seasonal environment (four dry and three wet seasons), cultivar, and type of exposure system. Thus, rice yields are not likely to be affected by increases in UV‐B under realistic field conditions.
Comparison of Empirical Equations for Temperature Correction of Gypsum Sensors
Authors: Aggelides Sotiris M. , Londra Paraskevi A. 
Published: July 2010

AbstractElectrical resistance gypsum sensors (two types from Soilmoisture Equipment Corp. and one type from Anti‐Sel Co.) were calibrated for temperature in a specially constructed box with thermal and moisture isolation. Results indicated that the relationship between log values of electrical resistance and temperature for different moisture contents of the porous sensors was linear. To convert electrical resistance values from the field temperature to a reference temperature of 25°C, an equation is proposed for the three different types of resistance sensors. Comparison tests indicated that our suggested equation gives better results, for these three types of gypsum sensors used under the current experimental conditions, than other empirical equations found in the literature.
Determination of Differential Carbon Dioxide Concentration by Conductimetric Analysis
Authors: Baker John M. 
Published: July 2010

AbstractThere are many applications in such disciplines as agronomy, plant physiology, and ecology where it is necessary to measure the difference in atmospheric CO2 concentration [CO2] between two points. This is commonly done with an infrared gas analyzer, but such instruments are expensive, representing a substantial and sometimes prohibitive share of the cost of CO2— related research. The goal of this project was to explore a simple inexpensive alternative, in which the difference in [CO2] between two air streams is determined by bubbling the air through cells containing deionized water while measuring the ratio of their conductivities with a half‐bridge measurement of electrode pairs suspended in each cell. The underlying principles are presented, and it is shown that (i) differential [CO2] is directly proportional to the conductivity ratio minus its inverse and (ii) the coefficient of proportionality is equal to the mean [CO2] of the two air streams. A system was designed and constructed to test these principles, and the results confirmed them. Dynamic response was characterized, and shown to be proportional to Q/V, where Q is the air flow rate and V is the water‐filled volume of the cell. Differential resolution was found to be in the range of 0.4 to 0.8 μmol mol−1, but better resolution is theoretically possible. Differential measurement of [CO2] by conductimetry shows considerable promise, particularly considering the straightforward nature of the relationship and the relatively low cost of the required components.
Rhizomatous Birdsfoot Trefoil Exhibits a Unique Response to Nitrogen‐Free Conditions
Authors: Kallenbach Robert L. , McGraw Robert L. , Beuselinck Paul R. , Balatti Pedro A. 
Published: July 2010

AbstractNew genotypes of birdsfoot trefoil (Lotus corniculatus L.) from Morocco exhibit rhizomes, but little is known about their N2‐fixation characteristics. Our objective was to evaluate the N2‐fixation capacity of rhizomatous birdsfoot trefoil infected by native rhizobia or by strains used in commercial inoculants. An additional objective was to assess the N2‐fixing potential of two Moroccan isolates, R.L. 5797 and R.L. 5758, on commercial cultivars of birdsfoot trefoil. Seedlings of ‘Norcen’, ‘AU Dewey’, and a Moroccan rhizomatous entry, designated ‘RBRC’, were individually inoculated with commercial strains BFT027, BFT028, BFT030, 1710‐2, CB756, or strains R.L. 5797 or R.L. 5758. Control treatments were noninoculated seedlings with or without supplemental N. Surprisingly, the seedling mass of RBRC was equal (P > 0.05) for all treatments. Norcen exhibited its greatest seedling mass when inoculated with strain BFT027; AU Dewey, with strain R.L. 5797. The rhizomatous RBRC did not show specificity for native Moroccan isolates of rhizobia, but these isolates effectively nodulated the commercial cultivars of birdsfoot trefoil.
Defoliation Timing and Severity in Sugar Beet
Authors: Muro Julio , Irigoyen Ignacio , Lamsfus Carmen 
Published: July 2010

AbstractDefoliation produced by different biotic and abiotic factors can reduce sugar beet (Beta vulgaris L.) sugar content and final yield production. Four trials were conducted to study the effect on sugar content and yield production of systematic defoliations carried out during the sugar beet growing cycle, in the Central Ebro Valley in Spain. In two trials, defoliation was achieved using shears, a largely untraumatic defoliation method, and in the other two by blasting with a pressurized water jet, producing a traumatic defoliation. Defoliations were performed at seven different growth stages (defined by heat sums and days from sowing). For each growth stage, four defoliation levels (control, slight, moderate, and heavy) were imposed. The results revealed a relationship between yield loss, level of defoliation, and growth stage when defoliation took place. The most critical growth stage for the effect of defoliation on yield was between 1700 and 1800 degree‐days, when 100% defoliation produced a 42% yield loss. The higher the level of defoliation, the higher the yield loss. This study produced a set of regression equations that can be used to assess final yield loss caused by defoliation of sugar beet by such different agents as hail storms, wind, insects, and other mechanical damage.
The Uprooting of Trees: A Forest Process
Authors: Stephens Earl P. 
Published: July 2010

AbstractFor many years the uprooting of trees has been recognized as a natural phenomenon. As such, it has usually been regarded as one of freakish occurrence noted for its direct and catastrophic results upon the trees immediately affected. Uprooting, it seems, has seldom been considered with enough perspective to reveal its basic relationship to the forest.A form of very detailed descriptive research was instigated in 1948 to document the developmental trends of the forest stands which had occurred on a 1‐acre area. Uprooting was established conclusively as an important factor in the development of the area during the last 500 years.When uprooting is observed and interpreted on a limited area with the perspective afforded by 500 years, its role becomes that of a natural forest process, rather than a single event in the life history of a forest stand. As a process, it must be considered along with reproduction, growth, podsolization, and other generally recognized processes. Similarly, the series of actions and subsequent reactions associated with uprooting can be described quantitatively, qualitatively, and chronologically.More extensive research has indicated that uprooting is a general forest process in eastern North America. Its influences have many ramifications, and like most other natural processes, are highly variable. The soil is one of the components of the forest greatly affected by the process of uprooting.
Effects of Bulk Density, Aggregate Size, and Soil Water Suction on Oxygen Diffusion, Redox Potentials, and Elongation of Corn Roots
Authors: Grable A. R. , Siemer E. G. 
Published: July 2010

AbstractCorn seeds (Zea mays L. ‘WF9 × 38‐11’) were planted in plastic cylinders of soil at different bulk densities (0.93, 1.03, 1.13, and 1.23 g cm‐3) or aggregates of different sizes (< 0.5, 0.5–1, 1–2, 2–3, and 3–6 mm). Soil water suction during germination was maintained at constant levels (0, 3, 18, 48, and 68 cm of water).Germination began and root elongation rates sharply increased from zero to a maximum in each soil sample as soil water suction increased above the air‐entry value or bubbling pressure. Over these ranges of suction, diffusion of O2 controlled rate of root elongation. Diffusion of O2 in soil was determined primarily by air porosity. Bulk density and aggregate size per se had little effect on diffusion or concentration of O2 at seed depth. Bulk density and aggregate size greatly influenced soil water desorption, the depth of soil to which O2 could diffuse, and the thickness of water films at equal air porosities. Between approximately 0 and 20 cm of suction, thickness of water films limited root elongation. Measured O2 concentrations in soil agreed with concentrations predicted by diffusion theory. Redox potentials were correlated with O2 levels. Root elongation rates decreased in some samples at the highest suctions used, probably because of increased soil strength.
Exchange of Diquat2+ in Soil Clays, Vermiculite, and Sniectite
Authors: Dixon J. B. , Moore D. E. , Agnihotri N. P. , Lewis D. E. 
Published: July 2010

AbstractClay samples were saturated with diquat2+ by a centrifuge washing procedure. Exchangeable diquat2+ was replaced by washing samples with 1N KCl solutions. Exchange of diquat2+ by K+ was 23 to 26% complete for three Wyoming montmorillonites and was 35 to 44% for three montmorillonite samples from Alabama and Mississippi. Diquat cations were 59% exchangeable in a nontronite. Diquat cations satisfied 57 and 82% of the cation exchange charge of Texas and Montana vermiculites and K+ replaced 98 and 88% of the diquat2+, respectively. There was a direct relationship between K+‐diquat2+ exchange and layer charge density (CEC) of the montmorillonites and vermiculites. Hydroxy‐Al interlayers had little influence on the exchange of diquat2+ in vermiculite and in montmorillonite except where double interlayers were deposited. Eleven soil clays had from 27 to 98% of their cation exchange charge countered by diquat2+. The exchangeability of diquat2+ in the diverse group of soil clays was directly related to vermiculite content. Montmorillonitic soil clays fixed more diquat2+ than vermiculitic soil clays. Diquat2+ was about 70% exchangeable in montmorillonitic soil clays which also contained vermiculite and kaolinite. The exchangeability of diquat2+ in montmorillonitic Houston and Iredell soil clays and their K+ fixing ability on oven drying indicate that vermiculite may have an important influence on their K+ exchange reactions.
Influence of Soybean and Corn Cropping on Soil Aggregate Size and Stability
Authors: Alberts E. E. , Wendt R. C. 
Published: July 2010

AbstractHigher rates of soil loss have been observed for soybean [Glycine max (L.) Merr.] cropping than for corn (Zea mays L.) cropping. The objective of this study was to determine whether 4 yr of continuous soybean and continuous corn cropping had altered the size and stability of soil aggregates within the tillage zone, which could affect soil seal formation and erodibility. Samples for analyses were obtained in June and October of 1980 from the Monona (fine‐silty, mixed, mesic, Typic Hapludolls) and Clarion (fine‐loamy, mixed, mesic, Typic Hapludolls) soils in Iowa. The mean‐weight diameter of dry‐sieved aggregates was significantly (p <0.05) lower for soybeans than corn in October, but the values were similar in June. The mean‐weight diameter of wet‐sieved aggregates was lower for soybeans than corn in both June and October, but the differences were not statistically significant. The mass of clay released from the bulk soil and two macroaggregate size fractions with laboratory shaking was slightly, but significantly (p <0.10), higher for corn than soybeans.
Metal (Hydr)oxide Surface‐Catalyzed Hydrolysis of Chlorpyrifos‐Methyl, Chlorpyrifos‐Methyl Oxon, and Paraoxon
Authors: Smolen Jean M. , Stone Alan T. 
Published: July 2010

AbstractThis work is concerned with the susceptibility of pesticides and their transformation products to mineral‐surface‐catalyzed hydrolysis in soils. Experiments were performed in an aqueous medium containing pH buffer [2.0–5.0 mM acetate or 3‐(N‐morpholino) propane sulphonic acid (MOPS)], 10 mM NaCl, and 0 to 25% methanol. Addition of 10 g L−1 TiO2, α‐FeOOH, and Al2O3 catalyzes the hydrolysis of the thionate (P=S) and oxonate (P=O) forms of chlorpyrifosmethyl [O,O‐dimethyl O‐(3,5,6‐trichloro‐2‐pyridinyl) phosphorothioate and O,O‐dimethyl‐O,3,5,6‐trichloro‐2‐pyridyl phosphate]. Paraoxon (O,O‐diethyl O‐p‐nitrophenyl phosphate) is also subject to surface‐catalyzed hydrolysis, while zinophos (O,O‐diethyl O‐2‐pyrazinyl phosphorothioate) is not. The effects of pH and the identity of the metal (hydr)oxide surface are discussed in light of three possible mechanisms of catalysis: (i) metal ion coordination of the parent ester through the thionate‐S or oxonate‐O to enhance the electrophilicity of the P site; (ii) metal ion coordination and induced deprotonation of water to create a reactive nucleophile; and (iii) metal ion coordination of the leaving group to facilitate its exit. Because different methanol concentrations were employed to ensure solubility, ester‐to‐ester comparisons must be made with caution. It is apparent, however, that surface‐catalyzed hydrolysis reactions provide a unique opportunity to explore the reactivity properties of soil mineral surfaces.
A ‘truly amiable gentleman’: new light on the life and work of Marmaduke Tunstall (1743–1790) of Wycliffe, North Yorkshire
Authors: BOYD M.J. , JESSOP L. 
Published: July 2010

Marmaduke Tunstall (1743–1790) was a naturalist, antiquary and collector. Active in London during the 1760s and early 1770s, he built up an extensive Library and a Museum that was particularly notable for its systematic collection of British birds. Tunstall corresponded with several of the leading British naturalists, and with Linnaeus, and made his collections available for study to several authors. At the age of 33, Tunstall retired to a country estate at Wycliffe on the south bank of the Tees, where he spent the rest of his life. Newly-discovered information is incorporated with previously-published data, to provide a new account of Marmaduke Tunstall's life and activities, as a background to other studies on his family and his collections.
Survival Patterns Among Patients With Breast Cancer in Sub-Saharan Africa
Authors: Limenih Miteku Andualem , Mekonnen Eskedar Getie , Birhanu Frehiwot , Jima Beshada Rago , Sisay Binyam Girma , Kassahun Eskeziaw Abebe , Hassen Hamid Yimam 
Published: May 2024

ImportanceBreast cancer is the most prevalent cancer globally with tremendous disparities both within specific regions and across different contexts. The survival pattern of patients with breast cancer remains poorly understood in sub-Saharan African (SSA) countries.ObjectiveTo investigate the survival patterns of patients with breast cancer in SSA countries and compare the variation across countries and over time.Data SourcesEmbase, PubMed, Web of Science, Scopus, and ProQuest were searched from inception to December 31, 2022, with a manual search of the references.Study SelectionCohort studies of human participants that reported 1-, 2-, 3-, 4-, 5-, and 10-year survival from diagnosis among men, women, or both with breast cancer in SSA were included.Data Extraction and SynthesisIndependent extraction of study characteristics by multiple observers was performed using open-source software, then exported to a standard spreadsheet. A random-effects model using the generalized linear mixed-effects model was used to pool data. The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guideline for reporting was followed.Main Outcome and MeasuresSurvival time from diagnosis.ResultsForty-nine studies were included in the review with a sample size ranging from 21 to 2311 (total, 14 459; 196 [1.35%] men, 13 556 [93.75%] women, and 707 [4.90%] unspecified; mean age range, 38 to 71 years), of which 40 were summarized using meta-analysis. The pooled 1-year survival rate of patients with breast cancer in SSA was 0.79 (95% CI, 0.67-0.88); 2-year survival rate, 0.70 (95% CI, 0.57-0.80); 3-year survival rate, 0.56 (95% CI, 0.45-0.67); 4-year survival rate, 0.54 (95% CI, 0.43-0.65); and 5-year survival rate, 0.40 (95% CI, 0.32-0.49). The subgroup analysis showed that the 5-year survival rate ranged from 0.26 (95% CI, 0.06-0.65) for studies conducted earlier than 2010 to 0.47 (95% CI, 0.32-0.64) for studies conducted later than 2020. Additionally, the 5-year survival rate was lower in countries with a low human development index (HDI) (0.36 [95% CI, 0.25-0.49) compared with a middle HDI (0.46 [95% CI, 0.33-0.60]) and a high HDI (0.54 [95% CI, 0.04-0.97]).Conclusions and RelevanceIn this systematic review and meta-analysis, the survival rates for patients with breast cancer in SSA were higher in countries with a high HDI compared with a low HDI. Enhancing patient survival necessitates a comprehensive approach that involves collaboration from all relevant stakeholders.
Clinician-Level Knowledge and Barriers to Hepatocellular Carcinoma Surveillance
Authors: Wong Robert J. , Jones Patricia D. , Niu Bolin , Therapondos George , Thamer Mae , Kshirsagar Onkar , Zhang Yi , Pinheiro Paulo , Kyalwazi Beverly , Fass Ronnie , Khalili Mandana , Singal Amit G. 
Published: May 2024

ImportanceSurveillance for hepatocellular carcinoma (HCC) in patients with cirrhosis is underused. Identifying potentially modifiable factors to address barriers in HCC surveillance is critical to improve patient outcomes.ObjectiveTo evaluate clinician-level factors contributing to underuse of HCC surveillance in patients with cirrhosis.Design, Setting, and ParticipantsThis survey study included primary care clinicians (PCCs) and gastroenterology and hepatology clinicians at 5 safety-net health systems in the US. Clinicians were surveyed from March 15 to September 15, 2023, to assess knowledge, attitudes, beliefs, perceived barriers, and COVID-19–related disruptions in HCC surveillance in patients with cirrhosis. Data were analyzed from October to November 2023.Main Outcome and MeasuresHCC surveillance knowledge was assessed with 6 questions querying the respondent’s ability to correctly identify appropriate use of HCC surveillance. Attitudes, perceived barriers, and beliefs regarding HCC surveillance and perceived impact of the COVID-19 pandemic–related disruptions with HCC surveillance were assessed with a series of statements using a 4-point Likert scale and compared PCCs and gastroenterology and hepatology clinicians.ResultsOverall, 347 of 1362 clinicians responded to the survey (25.5% response rate), among whom 142 of 237 (59.9%) were PCCs, 48 of 237 (20.3%) gastroenterology and hepatology, 190 of 236 (80.5%) were doctors of medicine and doctors of osteopathic medicine, and 46 of 236 (19.5%) were advanced practice clinicians. On HCC knowledge assessment, 144 of 270 (53.3%) scored 5 or more of 6 questions correctly, 37 of 48 (77.1%) among gastroenterology and hepatology vs 65 of 142 (45.8%) among PCCs (P &amp;lt; .001). Those with higher HCC knowledge scores were less likely to report barriers to HCC surveillance. PCCs were more likely to report inadequate time to discuss HCC surveillance (37 of 139 [26.6%] vs 2 of 48 [4.2%]; P = .001), difficulty identifying patients with cirrhosis (82 of 141 [58.2%] vs 5 of 48 [10.4%]; P &amp;lt; .001), and were not up-to-date with HCC surveillance guidelines (87 of 139 [62.6%] vs 5 of 48 [10.4%]; P &amp;lt; .001) compared with gastroenterology and hepatology clinicians. While most acknowledged delays during the COVID-19 pandemic, 62 of 136 PCCs (45.6%) and 27 of 45 gastroenterology and hepatology clinicians (60.0%) reported that patients with cirrhosis could currently complete HCC surveillance without delays.Conclusions and RelevanceIn this survey study, important gaps in knowledge and perceived barriers to HCC surveillance were identified. Effective delivery of HCC education to PCCs and health system–level interventions must be pursued in parallel to address the complex barriers affecting suboptimal HCC surveillance in patients with cirrhosis.