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PubMed1990

Soybean root distribution, top growth and yield responses to ambient ozone and soil moisture stress when grown in soil columns in greenhouses.

Soybeans (Glycine max. cv. Williams) were grown to maturity in soil columns within polyvinyl pipe and placed in greenhouses with charcoal filtered (CF) and nonfiltered (NF) air. In each greenhouse plants were grown with and without soil moisture stress (SMS). Targeted soil water potentials at 0.25 m for no SMS and between 0.45 and 0.60 m for the SMS regime were -0.05 and -0.45 M Pa, respectively. The 7 h (1000-1700 h EDT) mean O(3) concentrations (June-October) were 0.039 and 0.009 ppm in NF and CF air, respectively. Ozone and SMS in combination were less than additive in their effects on growth of the plant top and bean yields. Plants in CF air had 70% greater top weight, 58% more bean yield and 43% more root dry weight than in NF air. Both the plant and the seed weight from plants without SMS weighed 35% more than with SMS. Total root length in CF air for plants with and without SMS averaged 1.84 and 1.98 km, respectively, as compared to 1.59 and 1.66 km for plants with and without SMS in NF air. The resultsare different, so far as the combined effects of O(3) and SMS on yield and root growth are concerned, than in a similar field study by Heggestad and co-workers primarily because of the presence of a water table in the field but absence of it in the columns, as planned, in this experiment. It is unique to use large soil columns to study root distribution and length as related to the effects of ambient O(3) alone, and its combination with SMS.

Journal Article↗
PubMed1996

Effects of elevated CO2 nitrogen supply and tropospheric ozone on spring wheat. I. Growth and yield.

Spring wheat (Triticum aestivum L. cv. Minaret) was exposed to three CO(2) levels, in combination with two nitrogen fertilizer levels and two levels of tropospheric ozone, from sowing to ripening in open-top chambers. Three additional nitrogen fertilizer treatments were carried out at the lowest and the highest CO(2) level, respectively. Plants were harvested at growth stages 31, 65 and 93 and separated into up to eight fractions to gain information about biomass partitioning. CO(2) enrichment (263 microl litre(-1) above ambient levels) drastically increased biomass of organs serving as long-term carbohydrate pools. Peduncle weight increased by 92%, stem weight by 73% and flag leaf sheath weight by 59% at growth stage 65. Average increase in shoot biomass due to CO(2) enrichment amounted to 51% at growth stage 65 and 36% at final harvest. Average yield increase was 34%. Elevated nitrogen application was most effective on biomass of green tissues. Yield was increased by 30% when nitrogen application was increased from 150 to 270 kg N ha(-1). Significant interactions were observed between CO(2) enrichment and nitrogen application. Yield increase due to CO(2) ranged from 23% at 120 kg N to 47% at 330 kg N. Triticum aestivum cv. Minaret was not very responsive to ozone at 1.5 times ambient levels. 1000 grain weight was slightly decreased, which was compensated by an increased number of grains.

Journal Article↗
PubMed1996

The effect of fly ash on plant growth and yield of tomato.

A gradual increase in fly ash concentrations in the normal field soil (0, 10, 20...100% volume/volume) increased the porosity, water holding capacity, pH, conductivity, C.E.C., sulphate, carbonate, bicarbonate, chloride, P, K, Ca, Mg, Mn, Cu, Zn and B. Fly ash additions to soil caused significant reductions in nitrogen content, it being almost nil in 90 and 100%. Tomato plants grown in the ash-soil mixture showed luxuriant growth with bigger and greener leaves. Plant growth, yield, (flowering, fruiting, fruit weight/plant, mean fruit weight), carotenoids and chlorophylls were mostly enhanced in the treatments with 40-80% fly ash, being optimal at 50 or 60%. From 60 or 70% onwards, the measured parameters tended to reduce. At 100% fly ash, yield (weight of fruits/plant) was considerably reduced. The boron content of tomato leaves displayed a gradual increase with fly ash addition from 20% onwards, while response of foliar nitrogen was just the opposite. The most economic level of fly ash incorporation was 40%, which improved the yield and market value of tomato fruits (mean weight) by 81 and 30%, respectively.

Journal Article↗
PubMed1996

Neutron yields from interactions of GCR-like beams in stopping targets.

In order to accurately determine the radiation risk to astronauts from GCR, the nature of the secondary radiation field created by the fragmentation of GCR in shielding and tissue must be understood. Due to the their high penetrabilities, neutrons are an important component of the secondary radiation field, especially for astronauts protected by thick shielding on lunar or Martian bases. Neutron yields from 435A MeV and 272A MeV Nb stopping in Nb and Al targets are presented, along with some preliminary analysis of neutron yields from 155A MeV C stopping in Al. Energy spectra and angular distributions are shown for neutron energies above 20 MeV. The data provides some information about the dependence of the neutron yield on projectile energy and target mass. Comparisons of the data with BUU calculations are also shown.

Aluminum↗
PubMed1988

On the yield of new information from the selective requesting of post mortem examinations in oncology patients.

Traditionally, a high rate of post mortem (PM) examinations has been advocated, primarily for the quality control of clinical diagnosis. In days of increasing scrutiny of medical costs, the role of the 'routine' requesting of any investigation must be questioned, and we report here the results of a policy to request post mortem examinations selectively when there was a reasonable expectation that it would yield new information. Between 21/3/82 and 12/2/86 there were 1356 deaths in patients registered with the Department of Radiation Oncology, Westmead Hospital. During this period, 100 PM examinations were performed. The overall post mortem rate is thus 6.7%, but for patients dying whilst under our direct care it is 23%. The cause of death was changed in 9% of cases following PM examination. The ante mortem assessment of the remission status of irradiated volumes was confirmed in 69% but was not recorded in the post mortem report in 22%, in spite of the medical record being available to the pathologist. Minor modifications were made by PM examination to the establishment of primary tumor site, sites of metastatic disease, histological diagnosis and other significant pathological states. The autopsy is an expensive investigation: we conclude that the low yield of relevant new information in this selective series is a powerful argument against the traditional routine request. Indeed the yield of new information in cases when the histological tumour type was known was even lower. The necessity for a problem-orientated approach is apparent from the data on the remission status of treated sites.

Adult↗
PubMed1991

Yields of tar and other smoke components from UK cigarettes.

Since 1972, regular six-monthly surveys of cigarettes on sale in the UK have determined the yields of tar, nicotine and carbon monoxide in mainstream smoke. During 1983-1990, a series of special studies investigated the yields of a range of additional analytes and their inter-relationships with the routinely monitored components. The results for total cyanide (as hydrogen cyanide), total aldehydes (including acetaldehyde), acrolein, formaldehyde and nitrogen monoxide are summarized, and the full data for six low-molecular weight phenols and three polycyclic aromatic hydrocarbons (PAHs) are reported. It is concluded that with the exception of nitrogen monoxide, which is strongly dependent upon the type of tobacco, and the delivery of some phenols and PAHs, which may be affected to a minor extent by the design of cigarette, the three routinely monitored smoke components provide an adequate guide to the yields of the other analytes examined, across the range of manufactured cigarettes available in the UK in the 1980s.

Plants, Toxic↗
PubMed1977

Fluorescence decay and quantum yield characteristics of acridine orange and proflavine bound to DNA.

Fluorescence properties (quantum yield, decay curve, lifetime and polarization) of acridine orange and proflavine bound to DNA were examined as a function of nucleotide to dye (P/D) ratio. First, mean fluorescence lifetimes were determined by the phase-shift measurements. The lifetime and quantum yield of acridine orange increased in a parallel fashion with increasing P/D ratio. There was no parallel relation between the lifetime and quantum yield for proflavine; the lifetime showed a minimum around P/D equals 10...

Acridines↗
PubMed1979

Relationship between dose, time, and tumor yield in mouse dimethylhydrazine-induced colon tumorigenesis.

Colorectal tumor yield and volume data were obtained using 355 CF1 mice serially sacrificed up to 84 weeks following various dose levels of the carcinogen 1,2-dimethylhydrazine dichloride (DMH). Several conclusions were reached: (a) With increasing doses of DMH, there was an increased tumor yield and decreased latency period. (b) With repeated doses, there was a rapidly cumulative tumor yield. (c) New tumors continued to accumulate in the colon and rectum even at long intervals after the DMH treatments. This was substantiated by a positive correlation between the number of tumors per colon and the delay after DMH. In addition, when several tumors were present in the same mouse, their sizes were graded rather than uniform. These observations are consistent with a 2- or multi-step carcinogenesis mechanism. The latter implies that DMH induces a permanent transmissible alteration within some cells which thereafter will be at risk for further alterations capable of initiating cancer growth.

Animals↗
PubMed1986

Acetylcholinesterase hydrolyses chromogranin A to yield low molecular weight peptides.

The major soluble protein of bovine chromaffin granules chromogranin A was purified by reverse-phase high performance liquid chromatography. Brief incubations with either acetylcholinesterase or trypsin cleaved chromogranin A to yield two chromogranin-immunoreactive polypeptides which were similar in molecular weight to two of the major endogenous chromogranin polypeptides. A number of peptidase inhibitors which strongly inhibited tryptic digestion of chromogranin A also inhibited the acetylcholinesterase digestion, although they were less potent. More prolonged digestion of chromogranin A with acetylcholinesterase produced a large number of peptides which were similar to some of the endogenous chromogranin peptides in their elution profile by high performance liquid chromatography. In contrast, complete tryptic digestion of chromogranin A yielded peptides with a totally different elution profile. The experiments indicate that acetylcholinesterase possesses a peptidase activity which is similar, but not identical to trypsin, and suggest that a second non-tryptic activity is also present. They also suggest that acetylcholinesterase, an enzyme found in chromaffin cells, may process chromogranin A to yield lower molecular weight chromogranins in bovine chromaffin cells.

Acetylcholinesterase↗
PubMed1995

The development of Azospirillum as a commercial inoculant for improving crop yields.

Bacteria of the genus Azospirillum are nitrogen-fixing organisms that live in close association with plants in the rhizosphere. The Azospirillum-plant association leads to the enhanced development and yield of different host plants under appropriate growth conditions. This increase in yield is attributed mainly to an improvement in root development, an increase in the rate of water and mineral uptake by roots, and to a lesser extent, biological N(2) fixation. Worldwide data accumulated in the field over the past 20 years indicates that Azospirillum is capable of promoting the yield of agriculturally important crops in different soils and climatic regions. A.brasilense shows both chemotaxis and chemokinesis in response to temporal gradients of different chemoeffectors, thereby increasing the chance of root-bacterial interactions. Phytohormones synthesized by Azospirillum influence the host root respiration rate, metabolism and root proliferation and hence better the mineral and water uptake in inoculated plants. Positive effects of combined inoculation with Rhizobium have been reported for different legumes and were related to the favorable influence of Azospirillum on the nodule number, plant development, dry weight, and N(2) fixation. Additionally, A. brasilense produces the reserve material polyhydroxybutyrate comprising up to 70% of the cell dry weight This substance has received much attention recently as it can be extracted and formed into a biodegradable thermoplastic.

Journal Article↗
PubMed1994

No-carrier-added [123I]1-(beta-D-arabinofuranosyl)-5(E)-(2- iodovinyl)uracil (IVaraU): high yield radiolabeling via organotin and exchange reactions.

Organotin intermediates for IVaraU synthesis were obtained following the reaction of 1-(2',3',5'-tri-O-toluyl-beta-D-arabinofuranosyl-5-iodouracil with (E)-1,2-bis(tri-(n-butyl) stannyl)ethene in the presence of catalytic (Ph3P)2PdCl2. A direct precursor for IVaraU, (E)-5-[2-tri-n-butylstannylvinyl]-arabinosyluridine, reacted with [123I]NaI (10 mCi) or alternatively [125I]NaI in the presence of methanol and chloramine T providing no-carrier-added (NCA) [123I]IVaraU in a radiolabeling yield up to 97%; the product was recovered following reversed phase HPLC. Unlabeled IVaraU was prepared in five steps from arabinosyluridine via an organotin intermediate with an overall yield of 22%. An exchange radioiodination was also identified, based on accessible BrVara U in the presence of water and a cuprous ion catalyst. [123I]NaI (up to 40 mCi) or alternatively [125I]NaI reacted under exchange conditions to give no-carrier-added [123,125I]IVaraU in a radiolabeling yield of 93%; the product was recovered following reversed phase HPLC.

Antiviral Agents↗
PubMed2006

Yield and purity of 82Sr produced via the natRb(p,xn) 82Sr process.

The recently reported cross-section data for the production of 82Sr via the natRb(p,xn) 82Sr process were evaluated. For the natRb(p,xn) 85Sr process, cross-sections were measured experimentally over the proton energy range of 25-45 MeV, a region where very few data existed. An evaluation of the recently published data on the formation of 85Sr was then also performed. From the recommended data curves, the integral yields of the desired radionuclide 82Sr and the impurity 85Sr were calculated. Yields were also determined experimentally over several energy ranges using thick natRbCl targets. The experimental and calculated yields were found to be in agreement within 15%. These integral tests add confidence to the evaluated cross-section data. For the production of 82Sr, an incident proton energy of 60 MeV or above is recommended; the 85Sr impurity then corresponds to <20%.

Journal Article↗
PubMed2006

On the advantages of using green light to study fluorescence yield changes in leaves.

In photosynthetic chains, the kinetics of fluorescence yield depends on the photochemical rates at the level of both Photosystem I and II and thus on the absorption cross section of the photosynthetic units as well as on the coupling between light harvesting complexes and photosynthetic traps. A new set-up is described which, at variance with the commonly used set-ups, uses of a weakly absorbed light source (light-emitting diodes with maximum output at 520 nm) to excite the photosynthetic electron chain and probe the resulting fluorescence yield changes and their time course. This approach optimizes the homogeneity of the exciting light throughout the leaf and we show that this homogeneity narrows the distribution of the photochemical rates. Although the exciting light is weakly absorbed, the possibility to tune the intensity of the light emitting diodes allows one to reach photochemical rates ranging from 10(4) s(-1) to 0.25 s(-1) rendering experimentally accessible different functional regimes. The variations of the fluorescence yield induced by the photosynthetic activity are qualitatively and quantitatively discussed. When illuminating dark-adapted leaves by a weak light, the kinetics of fluorescence changes displays a pronounced plateau which precedes the fluorescence increase reflecting the full reduction of the plastoquinone pool. We ascribe this plateau to the time delay needed to reduce the photosystem I electron acceptors.

Color↗
PubMed2004

Influences of vermicomposts on field strawberries: 1. effects on growth and yields.

Vermicomposts processed commercially from food wastes and paper wastes were applied, to 4.5 m(2) field plots, under high plastic hoop tunnels, at rates of 5 or 10 tha(-1) to evaluate their effects on the growth and yields of strawberries (Fragaria ananasa) var. 'Chandler'. The vermicomposts were incorporated into the top 10 cm of soil and supplemented, based on chemical analyses, with amounts of inorganic NPK fertilizers calculated to equalize the initial fertilizer rates of 85-155-125 kgha(-1) NPK applied to the inorganic fertilizer plots. All treatments were replicated four times, in a completely randomized design, at two field sites on Doles silt loam or Hoytville silty clay loam at Piketon and Fremont, Ohio, respectively. Vermicompost applications increased strawberry growth and yields significantly; including increases of up to 37% in leaf areas, 37% in plant shoot biomass, 40% in numbers of flowers, 36% in numbers of plant runners and 35% in marketable fruit weights. These responses seemed not to be dose-dependent, since strawberries at one site grew fastest and yielded most in response to the 10 tha(-1) vermicompost application rate, whereas they responded positively and similarly to both the 5 and 10 tha(-1) rates of applications at the other site. These responses could not have been mediated by availability of macronutrients, since all plots were supplemented with inorganic fertilizers, to equalize macronutrient inputs for all treatments, but based on other research in our laboratory could have been due to production of plant growth regulators by microorganisms during vermicomposting.

Agriculture↗
PubMed2005

Effects of farmyard manure and fertilizers on yield, fibre quality and nutrient balance of rainfed cotton (Gossypium hirsutum).

Two-year field experiments were conducted to evaluate the effect of fertilizer with or without farmyard manure (FYM) application on cotton productivity and fibre quality. A partial nutrient balance was calculated by the difference method (nutrient applied--crop removal). Seed cotton yield was improved with addition of FYM (5 Mg ha(-1)). Application of both N and P resulted in significant improvements in seed cotton yield than the control and without N plots (PK). Uniformity ratio and ginning outturn (GOT) was greater in the FYM amended plots than the plots without FYM. Nitrogen and P balance was positive in the fertilizer-N and P applied plots whereas K balance was negative in spite of the addition of fertilizer-K. Potassium balance was positive only when FYM was applied. These studies suggest that it is advantageous to apply FYM as it improves fibre yield by way of improved GOT and maintains a positive nutrient balance.

Agriculture↗
PubMed2004

Effects of hypophysectomy and recombinant human growth hormone on material and geometric properties and the pre- and post-yield behavior of femurs in young rats.

To study the musculoskeletal effects of hypophysectomy (Hx) and a partial replacement treatment with recombinant human growth hormone (rhGH) in rats, we determined the stiffness (elastic modulus, E) and volumetric BMD (vBMD) of cortical bone; the periosteal and endosteal perimeters, area and bending moment of inertia (xCSMI) of the cross sections, and the structural stiffness and pre- and post-yield strength of the femur diaphyses by pQCT and mechanical tests, and the gastrocnemius weight of rats that were either intact (n = 9) or Hx at 15 days of age (20). The latter were otherwise untreated (Hx controls, 4) or given 0.4 (8) or 2.0 (8) IU kg(-1) day(-1), s.c., of rhGH for 45 days starting 15 days after surgery. Hx delayed musculoskeletal development (gastrocnemius weight, bone geometric properties), thus affecting the diaphyseal stiffness and strength. It also reduced the cortical vBMD through an undefined mechanism, and increased the elastic modulus of cortical bone. The Hx also affected the correlation between bone geometric and material properties (xCSMI vs. E), suggesting an antianabolic interaction with the biomechanical control of bone modeling in response to strains caused by mechanical usage. As a result, Hx reduced the stiffness, post-yield, and ultimate strength of the diaphyses. These effects should reflect changes in bone tissue microstructure, perhaps associated with crack generation and progress, but unrelated to bone mineral mass. They are compatible with the induction of a delay in collagen turnover with associated increases in fibers' diameter and crystals' size that may have resulted from the suppression of some other hormones, such as thyroid, prolactin, or other hormones regulated by ACTH. The above doses of rhGH significantly but incompletely prevented the negative Hx effects on bone and muscle development (bone geometric properties, muscle mass). However, rhGH treatment failed to prevent the demineralizing and stiffening effect of Hx on bone tissue and the unusual effects on the post-yield strength (less clearly related to muscle development than the former). Consequently, rhGH treatment tended to preserve the natural relationship between muscle function and bone geometry but not bone strength. The effects of larger rhGH doses and the interaction of other hormones with the described effects remain to be investigated. Nevertheless, these findings would deserve special attention because they challenge the prevailing view that in endocrine-metabolic bone-weakening diseases the bone matrix always has a normal composition.

Aging↗
PubMed2004

Essential oil yield and quality of methyl eugenol rich Ocimum tenuiflorum L.f. (syn. O. sanctum L.) grown in south India as influenced by method of harvest.

A field experiment carried out during 2001--2002 under semi-arid conditions of Hyderabad, India investigated the effect of three different methods of harvesting at full bloom stage, on essential oil yield and quality of methyl eugenol rich sacred/holy basil (Ocimum tenuiflorum L.f.; Lamiaceae). The harvest methods were: harvesting of primary branches, secondary branches and shoot biomass cut at 30 cm above ground level. Four harvests at 102, 192, 287 and 360 days after transplanting of the crop were taken in 1 year in each method of harvest. Harvesting of secondary branches led to maximum plant height and number of secondary branches per plant compared to harvesting of primary branches or shoot biomass cut at 30 cm above ground during second, third and fourth harvests. On the contrary, secondary branch harvest gave least biomass yield in all the four harvests. But due to higher essential oil content, secondary branch harvest gave 25.2 and 15.4% higher total (sum total of all four harvests) essential oil yield (kg/ha per year) over primary branches and shoot biomass cut at 30 cm above ground methods of harvesting, respectively. A similar treatment difference was observed in respect of oil composition studied in the first harvest. Harvesting shoot biomass at 30 cm above ground produced oil containing highest amount of methyl eugenol. The content of methyl eugenol decreased in the order of shoot biomass cut at 30 cm above ground > primary branch > secondary branch treatments. A reverse trend was observed, however, in respect of (E)-cinnamyl acetate, eugenol and beta-elemene constituents of the oil. Little variability was, however, observed among the treatments in respect of 24 other constituents of the oils.

Biomass↗
PubMed2005

Correlation of blood and milk components with the milk yield response to bovine somatotropin in dairy cows.

Our aim was to correlate the individual variation in the milk yield response (MYR) of Holstein dairy cows to bovine somatotropin (bST), with changes in milk plasmin and plasminogen activities as well as with plasma hormone and metabolite levels. Thirty-two housed multiparous Holstein cows (90 +/- 3.8 days post partum) received daily subcutaneous injections of saline for 1 week followed by subcutaneous injections of 20 mg/day of bST for 2 weeks. Blood samples were taken at approximately 4h intervals over 24 h at the end of the saline and bST treatment periods. Milk samples were also taken at the end of the saline and bST treatment periods. The difference in milk yield between the saline and the second week of bST treatment (MYR) varied considerably between animals (from -0.2 to +8.6 kg/day, relative to the saline treatment week). Low milk yield before bST treatment was associated with a high MYR. The plasma growth hormone response to treatment was negatively correlated with MYR. Plasma insulin-like growth factor-1 response to treatment was positively correlated with MYR. Furthermore, a high MYR to bST was associated with a lower milk plasminogen level before treatment and a greater reduction in the level of plasminogen in milk following treatment.

3-Hydroxybutyric Acid↗