Equal Yields Research Articles

Tillage System Effects on Soil and Plant Nutrient Distributions on Vertisols

Heavy clay soils, such as vertisols of the Texas Blackland Prairie (Houston Black clay [fine, montmorillonitic, thermic Udic Pellusterts]), are difficult to manage for crop production. Such soils typically require high draft for tillage; have limited opportunities for mobility, tillage, and planting; and produce variable crop performance when associated with highly variable weather patterns. This study compared the soil and plant nutrient distributions and yield performance of an experimental no-till farming system with a farming system using modified conventional chisel-till soil management. Raised wide beds and controlled traffic were used for both systems [...]

Yield Component Differences between Naked and Conventional Oat

AbstractGrain yield of naked oat (Avena sativa var. nuda L.) is lower than that of conventional hulled cultivars. This field study was conducted to determine yield component differences between naked and conventional oat and to assess the potential of naked oat as a grain crop for northern environments. Studies were conducted at the Viikki Experimental Farm, University of Helsinki, Finland, in 1991 and 1992. Grain yield and 24 morphophysiological traits of 10 naked and 6 hulled lines were compared. Grain yield was 30% lower in the naked lines than in the hulled ones. Due to the high hull content ( ≈ 25%) of conventional lines, they produced only 10% higher groat yields than the naked oat lines. Naked lines had fewer panicles per square meter, due to their lower emergence, suggesting that a 10% increase in planting density of naked lines may result in equal groat yields of naked and conventional lines. Compared with hulled lines, naked lines had higher vegetative phytomass associated with lower harvest index. When grains were dehulled, the harvest index of naked lines did not differ significantly from that of conventional lines. The naked oat lines were characterized by fewer spikelets per panicle and more grains per spikelet compared with hulled lines. To achieve high grain yield and increase the competitive ability of naked oat, improvement in partitioning photosynthetic assimilates into grain is needed.

On the elastic-plastic behaviour of woven fabric kevlar/epoxy composites

The flexural behaviour of woven fabric Kevlar/epoxy composites is different from their unidirectional counterparts. Unidirectional Kevlar/epoxy composites follow the elastic perfectly-plastic behaviour as analysed by many investigators [1-3]. However, in the woven fabric form they exhibit considerable 'work hardening' which is evident from the load deflection plots [4]. This 'work hardening effect' subsequent to yielding is due to the enlargement of the yielded region that increases the moment capacity of the beam. The ratio between the maximum moment Mm, to the yield moment My, is about 1.5 for an elastic perfectly plastic beam with equal yield stresses in tension and compression.

Cyclohexadiene and benzene derivatives of [Ru5C(CO)15

The reaction of [Ru5C(CO)15]1 with cyclohexa-1,3-diene and three equivalents of Me3NO yielded the new compound [Ru5C(CO)11(η4-C6H8)2]2 and also [Ru5C(CO)12(µ3-η2:η2:η2-C6H6)]3 and [Ru5C(CO)12(η6-C6H6)]4 in approximately equal yields. The molecular structure of 2 has been established by single-crystal X-ray diffraction. The two cyclohexadiene ligands are terminally bound on opposite basal ruthenium atoms of the square-pyramidal metal framework. Compound 2 may be converted to 3 by reaction with carbon monoxide. The isomeric pair [Ru5C(CO)10(µ3-η2:η2:η2-C6H6)(µ-η2:η2-C6H8)]5 and [Ru5C(CO)10(η6-C6H6)(µ-η2:η2-C6H8)]6 may be prepared from 3 and 4, respectively, upon reaction with cyclohexa-1,3-diene and two equivalents of Me3NO. Clusters 5 and 6 have also been studied by single-crystal X-ray diffraction. In both molecules the cyclohexadiene ligand bridges a basal edge of the square pyramid, while the benzene fragment is in face-capping and terminal bonding mode, respectively.

Assessment of Spatially Variable Nitrogen Fertilizer Management in Winter Wheat

Spatially variable N application may improve N use efficiency, grain yield, and net returns of winter wheat (Triticum aestivum L.) in fields exhibiting wide ranges of soil characteristics. The objectives of this study were to (i) determine the variability in optimal economic grain yield and in the amount of N required to produce a unit of grain at optimum yield, the unit N requirement (UNR), among landscape positions; (ii) evaluate landscape position as a criterion for dividing fields into units of equal productivity; and (iii) assess the economic benefits of spatially variable N fertilizer application [...]

Breeding silage maize with brown-midrib genes. Feeding value and biochemical characteristics

Summary - The effects of the maize brown-midrib genes bm3 and bm1 on feeding value and agronomic traits were investigated by animal studies and biochemical approaches. When sheep were fed bm3 silage, an increase in digestibility was observed, equal to 2.4 points for digestibility of organic matter (DOM), and 8.1 points for digestibility of crude fiber (DCF). Phenotypic variation was reduced for all observed traits of bm3 hybrids. This allowed the assumption that the bm3 gene acted by levelling to a similar value of almost 74% DOM, quite independently of the original value of the normal counterpart. The bm1 hybrids were intermediate between normal and bm3 ones for DOM, DCF and intake, but the dry matter yield was not reduced for bm1 hybrids. From experiments with young bulls, feed efficiency of INRA260 bm1 was not significantly improved, compared with normal INRA260, but INRA260 bm3 was a lot more efficient. Despite its lower adverse effect on agronomic characteristics of hybrids, the bm1 allele did not appear to be of any interest in improving the silage maize feed efficiency. Variations for lignin content due to the bm3 gene was similar for the 3 hybrids studied, despite their variation for susceptibility to root and stalk lodging. Ratios and content of alkali-labile hydroxycinnamic acids behaved similarly for the 3 hybrids, with a low yield of para-coumaric acid. Structural studies of lignin, after thioacidolysis, strengthened the results previously obtained, with a clear decrease of syringyl units, and the occurrence of the 5-hydroxyguaiacyl residue. The lignin of bm3 genotypes also appeared as a more condensed polymer than that of the normal types. The decrease of lignin content was observed in only 1 bm1 hybrid and appeared the same between normal and bm1 hybrids as between normal and bm3 hybrids. The lower yield of para-coumaric acid, and the equal yield of ferulic acid after alkaline hydrolysis of bm1 material were in good agreement with previous work. After thioacidolysis, the release of monomeric syringyl units was similar between bm1 and bm3, about 30% of the normal counterpart. However, it was very different for guaiacyl units, with a large decrease of the release of these units from the bm1 hybrid. The ratio between syringyl and guaiacyl units was about 0.3 for bm3 hybrids and about 1.3 for the bm1 hybrid. The lignin of this bm1 hybrid appeared as a very condensed polymer compared with the normal type. A large variation for digestibility was also found among normal hybrids. However, inbred lines inducing high digestibility often included unfavorable agronomic traits, such as poor yield, susceptibility to lodging or stalk rot. Second or third cycle lines following pedigree breeding might combine all traits, even if stalk standability and stalk digestibility are partly antagonistic. This method may be considered as easier than the bm3 method, but at present, the 2 ways are probably complementary, and worth investigating for improving silage digestibility, and simultaneously increasing knowledge on silage maize digestibility.

Lactational Response of Dairy Cows to Change of Degradability of Dietary Protein and Organic Matter

The effect of variable degradability of both OM and CP, incorporated at a constant ratio in diets of high yielding dairy cows (35 kg/d), was studied under commercial dairy herd conditions. Two diets containing 17% CP were formulated, including high (70%) and low (65%) protein degradability. The ratio of rumen-degradable OM to degradable protein was adjusted to 5:1 in both diets. Cows were assigned to treatments based on equal milk yield prior to trial, parity, and DIM. The trial lasted 7 wk: a reference week (wk 0), in which both groups were fed the high degradability diet, was followed by 6 experimental wk, in which group 1 was fed the high degradability diet and group 2 the low degradability diet. Cows on the low degradability diet consumed 1.2kg more DM and yielded 1.5 kg/d more milk, .055 kg/d more milk protein, and .196 kg/d more milk fat. Percentages of milk protein (3.06 and 3.03) were similar, but fat (3.67 and 3.28) was higher for cows fed the low degradability diet. The results suggest that, when diets were formulated to balance rumen degradability of both OM and CP, 65% rather than 70% degradability of CP was advantageous for yields of milk and milk components.

USING MECHANICAL PRUNING TO MITIGATE ALTERNATE BEARING OF PISTACHIOS

A single severe mechanical pruning done January, 1985, with the following treatments, hand pruned control, hedging, topping and topping and hedging, successfully reduced the alternate bearing of pistachios. The respective alternate bearing indexes are as follows; control, 0.88; hedged, 0.79, topped. 0.55, hedged and topped, 0.36. All treatments produced approximately equal cumulative yield over the 7 year experimental period. However, the most severely pruned trees demonstrated yield loss in the first 2 years after pruning.The severe mechanical pruning, done prior to the low crop year, produced its effects by forcing trees to produce less fruiting wood during the off-crop year. The effects of a single severe mechanical pruning persisted 7 years.

Co-purification of human serum lipoamidase and biotinidase: evidence that the two enzyme activities are due to the same enzyme protein

A more than 20000-fold purification of human serum lipoamidase is described. This was accomplished by (NH4)2SO4 precipitation and chromatography on DEAE-Sepharose, Blue Sepharose CL-6B and phenyl-Sepharose CL-4B, followed by preparative isoelectric focusing (IEF) and finally by gel-permeation chromatography. Co-precipitation and co-chromatography of lipoamidase and biotinidase activities with equal yields and purification were obtained in all the purification steps, indicating that lipoamidase and biotinidase activities in human serum are due to the same enzyme protein. After preparative IEF, two fractions with both lipoamidase activity and biotinidase activity were found at pI 4.0 and pI 4.4 respectively. The molecular mass of the enzyme was found to be 76 kDa. When 2-mercaptoethanol was used instead of cysteine as stabilizer during the purification procedure, only one major form (pI 4.0) of the enzyme was obtained after preparative IEF. By addition of cysteine, this form was transformed to an enzyme with pI 4.4, indicating that this latter form is a cysteine adduct, produced during the IEF procedure.

Cultivar maturity and potential yield of soybean

Soybean (Glycine max (L.) Merrill) cultivars from maturity groups 00, I, III, and V were grown in the field to evaluate the relationship between the length of total growth cycle and potential yield. Cultivars from maturity group 00 and I were grown in narrow rows (0.38 m) to obtain maximum insolation interception. The length of the vegetative growth period increased by 35 days from maturity group 00 to V. Plant size (total nodes per plant and maximum vegetative mass in g m−2) also increased with increasing maturity group. All cultivars reached maximum insolation interception soon after initial flowering. The crop growth rate of control plots (measured between growth stages R1 and R5) was not related to plant size. Shade (30 and 63%) from growth stage R1 to R7 was used to create variation in crop growth rate within a cultivar. For each cultivar, the number of seeds m−2 increased linearly with increasing crop growth rate. After adjusting for cultivar differences in individual seed growth rate, there were no cultivar differences in seeds m−2 at a constant crop growth rate. Thus, seeds m−2 was related to crop growth rate, not to the size of the plant. The maturity growth 00 cultivar tended to have a shorter seed-filling period but there were no consistent differences among the others. These data suggest that the longer vegetative growth period of later-maturing cultivars does not provide a higher yield potential and that shorter-season cultivars may have equal yield potential if exposed to a similar environment.

Inorganic grignard analogues. Reaction of nickel powder with dihalogenotriorganophosphorus compounds to form nickel-(II) and -(III) phosphine complexes; isolation of planar [Ni(PPh3)I3]? and the crystal structure of [Ni(PPhMe2)2Br2

Reactions of dihalogenotriorganophosphorus compounds R3PX2(X = Br or I) with unactivated coarsegrain nickel metal powder have been investigated. The nature of the nickel phosphine complexes formed is remarkably dependent on both R and X. Where R ≠ Me and X = I the nickel(II) complexes [R3PI][Ni(PR3)I3] are formed, analogous to, but not isostructural with, similar cobalt complexes of the same stoichiometry formed from cobalt powder and R3PI2. Quantitative electronic spectroscopic studies indicated that, surprisingly, the [R3PI][Ni(PR3)I3] complexes all have predominantly square-planar geometry around nickel. Where R = Me and X = I, the nickel(III) complex [Ni(PMe3)2I3] is obtained in quantitative yield, the other product being diiodine. Reaction of nickel powder with Me2PhPl2 yields both the nickel(II) complex, [Me2PhPI][Ni(PPhMe2)I3], and the nickel(III) complex, [Ni(PPhMe2)2I3]. These observations again mirror analogous cobalt reactions. Reaction of the analogous dibromo compounds, R3PBr2, with nickel powder is extremely sensitive to the nature of R. Where R = Me, Et or Pnn no reaction occurs; where R3= PhMe2 the square-planar complex [Ni(PPhMe2)2Br2] and an octahedral complex of stoichiometry Ni(PPhMe2)2Br4 are obtained in equal yield. Where R3= Ph2Prn the octahedral complex [Ni(PPh2Prn)2Br4] is formed with a trace of the planar complex [Ni(PPh2Prn)2Br2], and where R = Ph the octahedral complex [Ni(PPh3)2Br4] is formed in quantitative yield. The complex [Ni(PPhMe2)2Br2] has been crystallographically characterised: monoclinic, space group P21/a, a= 10.018(2), b= 10.249(1), c= 10.138(1)Å and Z= 2 (molecule centrosymmetric).

Site-directed cross-linking studies on the E. coli tRNA-ribosome complex: determination of sites labelled with an aromatic azide attached to the variable loop or aminoacyl group of tRNA.

tRNA(Phe) from E. coli, modified with the photoreactive label N-(p-azidobenzoyl)-glycine (ABG) either at the naturally occurring nucleotide 3-(3-amino-3-carboxy-propyl) uridine (acp3U47) or the alpha-amino group of Phe-tRNA(Phe), was bound nonenzymatically to 70S ribosomes in the presence of poly (U) or short synthetic mRNA molecules prepared by T7 transcription. The noncovalent complexes were subjected to a mild ultraviolet irradiation treatment and the sites of photo-incorporation were analysed. When the photo-affinity label was attached to the aminoacyl group cross-linking was observed from both A- and P-site bound tRNA and involved exclusively the 50S subunit. In both cases the major target of cross-linking was a single site in 23S RNA, localized to position A-2439. A lower yield of cross-linking to L27 from both P- and A-sites was also observed. In contrast, cross-linking from the acp3U47 derivative was specific for P-site bound tRNA and involved mainly (but not exclusively) the 50S subunit. In this case rRNA and ribosomal protein were labelled in approximately equal yields, the sites of cross-linking involving A-2309 in 23S RNA and L33. These results are discussed in the light of our present knowledge concerning the structural arrangement of the tRNA-ribosome complex.

Control of carbon dioxide in exhaust air as a method for equal biomass yields at different bed heights in a column fermentor

The rate of aeration of the medium in a solid state fermentation system for biomass production by Schwanniomyces castellii in a large column fermentor was found to influence the gradient of biomass yield at different bed heights. The variations were lower with a higher rate of aeration. These trends were used to formulate a successful strategy to ensure equal biomass yield at all the bed heights by controlling the level of CO2 at about 2% in exhaust air from the fermentor.

Metabolism of 11-deoxycorticosterone by hamster adrenal mitochondria

Metabolism of 11-deoxycorticosterone (DOC) by hamster adrenal mitochondria gives 19-hydroxy-DOC and corticosterone (via 11-hydroxylation) in approximately equal yields. The ratio of 19- to 11-hydroxylation was invariant with changes in concentration of substrate or a competitive inhibitor. It is most likely, therefore, that a single 11,19-hydroxylase catalyzes both oxidations. Both primary products are further oxidized to the corresponding carbonyl analogs, 19-oxo-DOC and 11-dehydrocorticosterone, at rates that are approx. 20% of their rates of formation. The oxidation of 11-dehydrocorticosterone is catalyzed by a dehydrogenase utilizing either NAD or NADP while the oxidation of 19-hydroxy-DOC is catalyzed by an oxidase requiring NADPH. The 11-dehydrocotiicosterone is stable in this enzyme preparation while 19-oxo-DOC is metabolized to two additional products, which are tentatively identified as 19-oic-DOC and 19-norcorticosterone. 19-nor-DOC was found to be hydroxylated at a rate that is 20% faster than the rate for DOC under the same conditions. It is therefore possible that 19-norcorticosterone can arise from 19-oic-DOC via decarboxylation to 19-nor-DOC and subsequent 11-hydroxylation, but the kinetics of its formation suggest that it may actually be formed directly from 19-oxo-DOC without free intermediates. 4-Androstene-3,17-dione and 17-hydroxy-DOC were also substrates for this 11,19-hydroxylase, but 18-hydroxy-DOC was not. Maintenance of hamsters on a low sodium diet had no effect on the metabolism of DOC by the isolated adrenal mitochondria.

DNA base damage in chromatin of gamma-irradiated cultured human cells.

We report on the chemical characterization of DNA base damage in chromatin of gamma-irradiated cultured human cells. Chromatin was isolated from unirradiated and irradiated cells and analyzed by gas chromatography/mass spectrometry with selected-ion monitoring after acidic hydrolysis of chromatin and trimethylsilylation of hydrolysates. Prior to analysis of chromatin samples, experimental conditions for acidic hydrolysis were optimized by determining the relative molar response factors of modified bases under non-acidic and acidic conditions, and their release from DNA under various acidic conditions. A number of modified bases in chromatin isolated from irradiated cells were identified and quantitated. These were 5-hydroxy-5-methylhydantoin, 5-hydroxyhydantoin, 5-(hydroxymethyl)uracil, cytosine glycol, thymine glycol, 5,6-dihydroxycytosine, 4,6-diamino-5-formamidopyrimidine, 8-hydroxyadenine, 2-hydroxyadenine, 2,6-diamino-4-hydroxy-5-formamidopyrimidine, and 8-hydroxyguanine. Radiation doses ranging from 42 to 420 Gy (J.kg-1) were used. Background levels of all modified bases were observed in chromatin isolated from unirradiated cells. The radiation yields of a number of modified bases were increased significantly over their background levels at a dose as low as 42 Gy. In most cases, linear dose-yield relationships were obtained up to approximately 200 Gy. At radiation doses higher than 420 Gy, no additional increase in the yields of modified bases was observed. The yields of guanine-derived bases amounted to approximately 45% of the total net yield of modified bases measured, followed by almost equal yields of adenine-, cytosine- and thymine-derived bases. Modified bases identified were typical products of hydroxyl radical attack on DNA bases, indicating the involvement of hydroxyl radical, although their induction in part by the direct effect of ionizing radiation through ionization of DNA bases cannot be excluded. The yields of modified bases were lower than those previously measured after gamma-irradiation of fully expanded chromatin in aqueous buffer solutions.

STUDIES ON THE UTILITY OF LEUCAENA AS GREEN LEAF MANURE ON N ECONOMY IN RICE (IR 20)

Studies on Leucaena as green leaf manure with sub optimal levels of N on N economy in rice revealed that combined application of Leucaena @ 101.ha' along with 50 kg N recorded equal grain yield to that of recommended level of 100kg ha''N. The combined application of Leucaena with 75kg N ha' was found to be significantly superior in recording higher grain yield over the recommended level of 100kg N ha-1.

A comparison of the effects of single or multiple spring applications of prilled urea or ‘Nitro-chalk’ to winter oilseed rape (Brassica napus)

SUMMARYAn earlier report of leaf scorch and diminished yield when using large amounts of urea on winter oilseed rape (Brassica napus) was investigated by applying 200 kg N/ha as calcium ammonium nitrate (‘Nitro-chalk’) or urea as a single dressing or divided in six ways. The ‘single-low’ variety Mikado (low in erucic acid) was grown in 1986 and was compared with the ‘double-low’ variety Ariana (low in erucic acid and glucosinolates) in 1987 and 1988. No scorch was seen in these experiments. Yield from rape fertilized with prilled urea was, on average, 98% of that from rape fertilized with ammonium nitrate. The timing and distribution of the fertilizer also had little effect on yield, though yield slightly decreased when part of the dressing was withheld during March. The earlier-maturing variety Mikado always outyielded Ariana except when harvest was delayed by bad weather.When plots were fertilized with urea, the oil content of the seed was a little larger than when fertilized with Nitro-chalk, which compensated for the smaller seed yield, resulting in almost equal oil yield from both forms of N fertilizer. Crude protein content was lower after a large single dose of urea fertilizer but parity with ammonium nitrate was restored by smaller amounts applied on a number of occasions. Neither form nor timing of N fertilizer had any consistent effect on the total glucosinolate content.The incidence of disease was significantly greater in rape given either form of N fertilizer than where none was given, but when downy mildew (Peronospora parasitica) was prevalent on pods there was significantly less infection in plots fertilized with urea than with ammonium nitrate.

Studies on the availability of Azolla N and urea N for rice growth using 15N

Field experiments (20 m2 plots) were conducted to compare Azolla and urea as N sources for rice (Oryza sativa L.) in both the wet and dry seasons. Parallel microplot (1 m2) experiments were conducted using 15N. A total of approximately 60 kg N ha-1 was applied as urea, Azolla, or urea plus Azolla. Urea or Azolla applied with equal applications of 30 kg N ha-1 at transplanting (T) and at maximum tillering (MT) were equally effective for increasing rice grain yields in both seasons. Urea at 30 kg N ha-1 at T and Azolla 30 kg N ha-1 at MT was also equally effective. Urea applied by the locally recommended best split (40 kg at T and 20 kg at MT) gave a higher yield in the wet season, but an equal yield in the dry season. The average yield increase was 23% in the wet season, and 95% in the dry season. The proportion of the N taken up by the rice plants which was derived from urea (%NdfU) or Azolla (%NdfAz) was essentially identical for the treatments receiving the same N split. Recovery of 15N in the grain plus straw was also very similar. Positive yield responses to residual N were observed in the succeeding rice crop following both the wet and dry seasons, but the increases were not always statistically significant. Recovery of residual 15N ranged from 5.5 to 8.9% for both crops in succeeding seasons. Residual recovery from the urea applications was significantly higher than from Azolla in the crop succeeding the dry season crop. Azolla was equally effective as urea as an N source for rice production on a per kg N basis.

Effect of tillage and straw on yield and N uptake of barley grown under different N fertility regimes

Cereal grains often yield less under zero tillage compared with conventional tillage. The objective of this study was to find whether yields could be made similar for the two tillage methods through increasing rates of fertilizer nitrogen (N). Field experiments with barley ( Hordeum vulgare L. cultivar ‘Galt’) were conducted from 1984 to 1987 at two locations (Innisfail in central Alberta and Rimbey in north-central Alberta). There were two tillage treatments (zero and conventional), two levels of straw (straw-off and straw-on) and four levels of urea fertilizer N (0, 33, 67 and 100 kg N ha −1). The N fertilizer was banded (4 cm beside and 4 cm below the seed row) at time of sowing. Grain yields or whole plant yields (grain plus straw) were less under zero tillage than conventional tillage at low N rates (0 or 33 kg N ha −1), but at the high N rates (67 or 100 kg N ha −1) zero tillage produced equal or greater yields at both locations. The straw-on treatment tended to have less yield than the straw-off, treatment, but the tendency was reversed when the N rates were high. Yield increases from applied N, indicated fertilizer N was more effective under zero tillage than conventional tillage, and it was more effective when straw was retained than removed. The N uptake followed approximately a similar pattern. This study, which employed banding of N, indicated that with zero tillage the yields of barley can equal those with conventional tillage, provided that rates of N are relatively moderately high.

Slow-particle-induced kinetic electron emission from a clean metal surface: A comparison for neutral and ionized projectiles.

Electron emission from a clean gold surface bombarded by slow (v1 a.u.) neutral or singly charged atoms has been investigated both experimentally and theoretically. The determination of electron-emission statistics for 1--16-keV ${\mathrm{H}}^{+}$, ${\mathrm{H}}^{0}$, ${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$, ${\mathrm{He}}^{+}$, ${\mathrm{He}}^{0}$, ${\mathrm{Ne}}^{+}$, ${\mathrm{Ne}}^{0}$, ${\mathrm{Ar}}^{+}$, and ${\mathrm{Ar}}^{0}$, respectively, delivered accurate total electron-emission yields, which are consistently higher for positively charged ions than for the corresponding isoenergetic neutral atoms. It was assured that potential emission could not be responsible for the observed differences. ${\mathrm{H}}^{\mathrm{\ensuremath{-}}}$ bombardment at low impact energy causes equal yields as for ${\mathrm{H}}^{0}$, but for higher kinetic energy even the yields for ${\mathrm{H}}^{+}$ are surpassed. The results are explained with a semiempirical theory for heavy-particle-induced electron emission, assuming different screening of projectile cores by the accompanying electron(s) during the continuous change of projectile charge upon penetration of the solid. For ${\mathrm{H}}^{+}$,${\mathrm{H}}^{0}$ bombardment a quantitative description of the experimentally observed effects could be achieved by calculation of the stopping power for slow projectiles in different charge states, together with the electron-capture and -loss cross sections for these projectiles colliding with the target atoms.