Showing papers by "University of New Hampshire published in 1977"

III. Coalescence as a Rate-Controlling Process

Abstract: Oxide and carbon particles in flames are observed to grow by inter-particle Brownian collision and fusion, Previous investigators have tacitly assumed that coalescence is instantaneous and that growth is controlled solely by the collision frequency. Growing particles, however, are often found to be flocculated, suggesting that fusion rather than collision is the rate controlling process. In this study, a growth rate expression is derived which considers both collision and coalescence phenomena. A new parameter is introduced, Np, the number of primary particles within a Hoc. Predicted values of Np were compared with those estimated from electron micrographs of silica aggregates. Comparison of predicted with measured values of Np is inconclusive. Better data, in situ, for aggregates in flames are needed.

The effects of sand movement on intertidal seaweeds and selected invertebrates at Bound Rock, New Hampshire, USA

Abstract: A seasonal study of sand movement and the benthic intertidal organisms at Bound Rock, New Hampshire, USA was conducted between November, 1973 and February, 1975. The site is subjected to irregular sand fluctuations, as well as diurnal, neapspring and major summer sand intrusions. The abundance and distribution of intertidal species was interrelated with the historical sand fluctuations at the area. For example, the lower limits of Mytilus edulis, Balanus balanoides and Porphyra umbilicalis approximated the highest summer sand elevations. Highly abraded rock surfaces in the lower intertidal zone were dominated by opportunistic annuals (e.g. Enteromorpha spp.) and perennial psammophytic or sand-loving seaweeds (e.g. Ahnfeltia plicata and Sphacelaria radicans). Overall, the intertidal seaweed populations at Bound Rock showed a lower number of perennials and fewer species than adjacent rocky shores. The low species diversity of seaweeds at the study site is attributable to unstable environmental conditions and a limited number of habitats. Even so, several psammophytic microhabitats are evident at Bound Rock depending upon the extent of sand burial and abrasion. The morphological and reproductive adaptations of several psammophytic species are discussed.

Cosmic ray investigation for the Voyager missions: Energetic particle studies in the outer heliosphere - and beyond

Abstract: A cosmic-ray detector system (CRS) has been developed for the Voyager mission which will measure the energy spectrum of electrons from ≈3–110 MeV and the energy spectra and elemental composition of all cosmic-ray nuclei from hydrogen through iron over an energy range from ≈ 1–500 MeV/nuc. Isotopes of hydrogen through sulfur will be resolved from ≈ 2–75 MeV/nuc. Studies with CRS data will provide information on the energy content, origin and acceleration process, life history, and dynamics of cosmic rays in the galaxy, and contribute to an understanding of the nucleosynthesis of elements in the cosmic-ray sources. Particular emphasis will be placed on low-energy phenomena that are expected to exist in interstellar space and are known to be present in the outer Solar System. This investigation will also add to our understanding of the transport of cosmic rays, Jovian electrons, and low-energy interplanetary particles over an extended region of interplanetary space. A major contribution to these areas of study will be the measurement of three-dimensional streaming patterns of nuclei from H through Fe and electrons over an extended energy range, with a precision that will allow determination of anisotropies down to 1%. The required combination of charge resolution, reliability and redundance has been achieved with systems consisting entirely of solid-state charged-particle detectors.

TheB locus (MHC) in the chicken: Association with the fate of RSV-induced tumors

Abstract: The fate of tumors induced by Rous sarcoma virus (RSV) was determined in anF 2 population segregating at three alloantigen loci. TheF 1 resulted from crossing tumor-resistant RPRL line 61 (B 2 B 2 D 3 D 3 I 2 I 2) with tumor-susceptible RPRL line 151 (B 5 B 5 D 4 D 4 I 8 I 8). Among theF 2 segregantsB 2 B 2,B 2 B 5, andB 5 B 5, the percentage of chicks dying of terminal tumors (by 70 days post-inoculation) was 5, 26, and 93, respectively (P≦0.01). NeitherD orI genotypes nor sex significantly affected tumor growth. In chickens with terminal tumors, the incidence of metastatic lesions was also significantly associated withB genotypes. Thus, the MHC chromosomal region in the chicken appears to exert a crucial role in determining the outcome of RSV-induced tumors.

Solar particle propagation from 1 to 5 AU

Abstract: A statistical analysis of solar particle events, observed by the GSFC-UNH charged particle detector on board Pioneer 10 and Pioneer 11 from March 1972 to December 1974 (from 1 to 5 AU for each spacecraft), is carried out with the goal of experimentally determining the statistical average interplanetary propagation conditions from 3 to 30 MeV. A numerical propagation model is developed that includes diffusion with a diffusion coefficient of the form k r =k o r β , convection, adiabatic deceleration, and a variable coronal injection profile. The statistical analysis is carried out by individually analyzing each of five parameters (t max, ξ(tmax), Δt 5, τ) that are uniquely defined in a solar particle event. Each of the five parameter data sets were analyzed in terms of both a spacecraft-solar flare connection longitude ≤50°, and a numerical model that employed a variable exponential decaying coronal injection profile. The five individual parameter analyses are combined with the results that the statistical average radial interplanetary diffusion coefficient from 1 to 5 AU is given by 〈k r〉 = (1.2 ± 0.4) × 1021 cm2 s-1 with 〈β〉 = 0.0± 0.3 for 3.4 to 5.2 MeV protons and 〈k r〉 = (2.6 ± 0.6) × 1021 cm2 s-1 with (β) = 0.0± 0.3 for 24 to 30 MeV protons. Using the classical relationship for the radial scattering mean free path λr, i.e. k r = υλr/3, we obtain 〈λr〉 = 0.09 ± 0.03 AU and 0.075 ± 0.020 AU for the low and high energy data, respectively. These results show, from 1 to 5 AU and from 3 to 30 MeV, that 〈λr〉 is both independent of radial distance and approximately independent of rigidity (for 〈λr〉~P α, where P = rigidity, α = -0.15 ± 0.20). The above diffusion coefficients are inconsistent With both the predictions of the diffusion coefficient from present theoretical transport models and with the diffusion coefficient used in modulation studies at low energies.

Feeding of the copepod Acartia tonsa on the diatom Nitzschia closterium and brown algae (Fucus vesiculosus) detritus

Abstract: Clearance, ingestion and incorporation rates of the copepod Acartia tonsa were measured using the diatom Nitzschia closterium and Fucus vesiculosus detritus. Mean clearance rates ranged from 1.5 to 3.7 ml copepod-1 day-1 on N. closterium and from 1.6 to 5.3 ml copepod-1 day-1 on 28 day-aged F. vesiculosus detritus. The copepods ingested from 0.05 to 0.29 μgC μg copepod C-1 day-1 feeding on N. closterium and from 0.06 to 0.81 μgC μg copepod C-1 day-1 on 28 day-aged F. vesiculosus detritus. N. closterium (4 to 6 μm diameter) is at the lower size limit of retention efficiency of A. tonsa as compared to the F. vesiculosus detritus used (10 to 24 μm diameter). Therefore, the greater feeding rate of A. tonsa on detritus was probably due to greater particle size. Relative levels of incorporation efficiency measured over several food concentrations ranged from 18 to 55% for P32-labelled N. closterium and 10 to 45% for 28 day-aged Zn65-labelled F. vesiculosus detritus. Incorporation rates of A. tonsa fed differently aged F. vesiculosus (0, 14, 28 and 56 days) ranged from 2.92 μg F. vesiculosus μg copepod-1 day-1 for unaged detritus to 0.06 μg F. vesiculosus μg copepod-1 day-1 for 56 day-aged F. vesiculosus detritus. Although the percent nitrogen of the detritus increased with age, A. tonsa had a greater incorporation rate on fresh detritus, which had a larger mean particle diameter than older detritus. As both P32 and Zn65 are not as metabolically labile as carbon, incorporation rates are probably underestimates of the true values. While A. tonsa was able to grow and reproduce on N. closterium, they did not survive on variously aged F. vesiculosus detritus. Cannibalism occurred in the A. tonsa cultures, so growth results are relative.

Solar Particle Propagation from 1 to 5 AU

Abstract: A statistical analysis of solar particle events, observed by the GSFC-UNH charged particle detector on board Pioneer 10 and Pioneer 11 from March 1972 to December 1974 (from 1 to 5 AU for each spacecraft), is carried out with the goal of experimentally determining the statistical average interplanetary propagation conditions from 3 to 30 MeV. A numerical propagation model is developed that includes diffusion with a diffusion coefficient of the form k r =k o r β , convection, adiabatic deceleration, and a variable coronal injection profile. The statistical analysis is carried out by individually analyzing each of five parameters (t max, ξ(tmax), Δt 5, τ) that are uniquely defined in a solar particle event. Each of the five parameter data sets were analyzed in terms of both a spacecraft-solar flare connection longitude ≤50°, and a numerical model that employed a variable exponential decaying coronal injection profile. The five individual parameter analyses are combined with the results that the statistical average radial interplanetary diffusion coefficient from 1 to 5 AU is given by 〈k r〉 = (1.2 ± 0.4) × 1021 cm2 s-1 with 〈β〉 = 0.0± 0.3 for 3.4 to 5.2 MeV protons and 〈k r〉 = (2.6 ± 0.6) × 1021 cm2 s-1 with (β) = 0.0± 0.3 for 24 to 30 MeV protons. Using the classical relationship for the radial scattering mean free path λr, i.e. k r = υλr/3, we obtain 〈λr〉 = 0.09 ± 0.03 AU and 0.075 ± 0.020 AU for the low and high energy data, respectively. These results show, from 1 to 5 AU and from 3 to 30 MeV, that 〈λr〉 is both independent of radial distance and approximately independent of rigidity (for 〈λr〉~P α, where P = rigidity, α = -0.15 ± 0.20). The above diffusion coefficients are inconsistent With both the predictions of the diffusion coefficient from present theoretical transport models and with the diffusion coefficient used in modulation studies at low energies.

Language in Child and Chimp

Abstract: Today one can scarcely read a daily newspaper or news magazine without encountering a feature extolling the latest linguistic accomplishments of one or another ape. Contemporary introductory psychology textbooks may devote as much space to the achievements of the likes of Sarah and Washoe as they do to the language development of children. With increasing frequency, widely ready journals such as Science publish reports of the transmutation of base primates into noble ones. It is no wonder there is a growing belief among students and scientists alike that modern behavioral science has in fact succeeded in teaching human language to apes.

Electron Spin Resonance Analysis of Semiquinone Free Radicals of Aquatic and Soil Fulvic and Humic Acids

Abstract: We analyzed the solid state and aqueous solution electron spin resonance (esr) spectra of Oyster River and Podzol soil fulvic and humic acids. Because the aqueous solution esr spectra mimic the behavior of the model compound para-benzosemiquinone, we conclude that semiquinone free radicals predominate in fulvic acid. In addition a decrease in spin concentration at a potential of 0.20 volts (vs. SCE) demonstrates that the semiquinone radicals are at least partially responsible for the reducing capability of humic materials. From the above results we devised a quantitative semiquinone analysis for humic materials.

Direct measurements of excited-state lifetimes in Mg, Ca, and Sr†

Abstract: The lifetimes of the lowest 3S1 states in Mg, Ca, and Sr have been measured. In addition, the lifetimes of a number of excited 1S0 and 1D2 states in Ca have been determined, as well as the lifetime of the 4s4p1P1 state of Ca. The measurements were made by observing the exponential decay of the intensity of the fluorescence emitted from excited states selectively populated by one- and two-step dye-laser excitation. The values obtained for the 3S1 lifetimes were τ(Mg) = (9.7 ± 0.5) ns, τ(Ca) = (11.7 ± 0.6) ns, and τ(Sr) = (12.9 ± 0.7) ns.

Mating behavior of Centropages typicus (Copepoda: Calanoida)

Abstract: Observations were made on approximately 300 mating couples of Centropages typicus Kroyer. Mating behavior consists of 4 distinct stages: pre-copulation, spermatophore extrusion, copulation, and post-copulation. Successful copulation requires proper positioning of the spermatophore complex on the female urosome and is dependent upon precise movements and orientation of the male during the mating encounter. Sub-optimal mating encounters, resulting in the improper placement of the spermatophore complex, were observed and adaptations tending to reduce spermatophore wastage are discussed.

Using Writing About Mathematics as a Teaching Technique.

Abstract: IT HAS been stated that the modern mathematics curricula emphasize the rela tionships between concepts (structure) as opposed to rote learning (Begle 1971; Cam bridge Conference 1963). This article is concerned with a "revelation" that came about from an experiment (Geeslin 1973) and subsequent clinical work concerning students' learning of mathematical struc ture. During the experiment, this is the re sponse obtained from one sixth grader who was asked to write about the relationship between two probability concepts: "Event is Outcome's cousin." From an empirical point of view, this response was not very useful. However, from a pedagogical point of view, it is intriguing and suggestive. Ques tions raised by such responses and sugges tions for teachers based on these responses are the focus of this article. In investigating the learning of mathe matical structure and its connection to achievement (Geeslin 1973; Geeslin and Shavelson 1975[a] and 1975[b]), students were asked to write sentences and para graphs concerning the relationships be tween pairs of probability concepts. Stu dents from grades 4 through 12 were taught elementary probability through a pro grammed text. Instruction lasted approx imately two weeks. Results clearly indicated that most students at all levels learned ele mentary probability and the mathematical structure involved. Students were asked to complete achievement, attitude, word asso ciation, and writing tasks before and imme diately after instruction, and two weeks later to check retention. Of main interest here are the writing tasks, which required students to write sentences or paragraphs about concepts or the relationships be tween concepts.

Method and apparatus for the production of secondary metabolites by the maintenance-state cultivation of microorganisms

Abstract: A fermentation vessel is used to grow a cell mass and maintain it in a maintenance energy state. In this state the mass of the cell material is maintained substantially constant, and fresh medium containing an energy source is introduced to the vessel at a rate sufficient to sustain cell viability but insufficient to support growth of the cell mass. Fluid with suspended cells is pumped from the vessel to a separator which separates a fraction of the fluid from the cells and discharges the fraction, the unfiltered portion of the fluid and substantially all of the cells being returned to the vessel, the discharged fraction containing useful secondary metabolites.

A computer system for visual recognition using active knowledge

Abstract: T h i s r e p o r t d e s c r i b e s r e s e a r c h done a t t h e A r t i f i c i a l I n t e l l i g e n c e L a b o r a t o r y o f t h e Massac h u s e t t s I n s t i t u t e o f T e c h n o l o g y . S u p p o r t f o r t h e l a b o r a t o r y ' s a r t i f i c i a l i n t e l l i g e n c e r e s e a r c h i s p r o v i d e d i n p a r t b y t h e Advanced Research P r o j e c t s Agency o f t h e Depar tment o f De fense under O f f i c e o f Nava l Research c o n t r a c t N00014-75 -C0643 . The r e p o r t i s based upon t h e a u t h o r ' s P h . D . d i s s e r t a t i o n f o r t h e Depar tment o f E l e c t r i c a l E n g i n e e r i n g and Computer S c i e n c e , M . I . T . , 1975. ' C u r r e n t a d d r e s s : Depar tment o f Ma thema t i c s and Computer S c i e n c e , U n i v e r s i t y o f New Hampsh i re , Durham, N .H . 03824 .

Societal morphogenesis and intrafamily violence in cross‐cultural perspective*

Abstract: There is an obvious similarity between what these two inhabitants of such vastly dissimilar islands are saying: namely, that the marital relationship is tinged by physical aggression, t o say nothing of other forms of aggression.? The fact that the marital relationship is also often characterized by warmth, affection, or solidarity is not inconsistent with the simultaneous existence of aggression because aggressive acts can be counternormative, o r because norms permitting or encouraging aggression between spouses can and d o exist simultaneously with norms stressing warmth and ~ o l i d a r i t y . ~ ~ I began this paper with these two quotations because they dramatically illustrate the high frequency or perhaps even the near universality with which aggression and violence of all types occur within the family. Obviously, I

Vectoring gypsy moth nuclear polyhedrosis virus by Apanteles melanoscelus (Hym.:Braconidae)

Abstract: Gypsy mothLymantria dispar L. larvae were exposed toApanteles melanoscelus (Ratzeburg) females contaminated with nuclear polyhedrosis virus. Three methods of contamination (ovipositor, total body surface, and exposure to infected hosts) and two exposure periods (2 and 24 hours) were tested. A significantly greater incidence of larval mortality caused by virus occurred among larvae exposed to contaminated than among larvae exposed to uncontaminated parasites for 2 and 24 hours. No significant differences occurred in larval mortality caused by virus for the 3 methods of contamination for the 2- and 24-hour tests or in parasite emergence from larvae parasitized by contaminated or uncontaminated parasites.

The alkaline proteases of Argiope and their possible role in web digestion

Abstract: The digestive fluid of Argiope was assayed for its proteolytic activity with selected natural and synthetic substrates. 1 Peak proteolytic activity was observed at pH 7.8. This was coincident with the pH of the digestive fluid. 2 Elastolytic and weak chymotryptic activities were detected. Limited activity toward collagen was also observed. Activity toward substrates for trypsin, leucine aminopeptidase and carpboxypeptidase A and B was absent. 3 Evidence demonstrating the in vitro digestion of web fibroin was obtained. The viscid spiral was susceptible to a variety of proteases; the radial fibers to the spider enzyme alone. 4 Of a series of inhibitors studied, EDTA had the greatest effect upon the spider proteases. This effect was temperature dependent.

Measurement of the lowest S-state lifetime of Al, Ga, In, and Tl†

Abstract: The lifetimes of the lowest 2S1/2 state in Al, Ga, In, and Tl have been measured by observing the exponential decay of the fluorescence arising from the 2S1/2–2P3/2 transition in each atom, following selective excitation of the 2S1/2 state by an N2 laser-pumped dye laser The values obtained for the 2S1/2 state lifetimes were τ(A1) = (68 ± 03) ns, τ(Ga) = (70 ± 04) ns, τ(In) = (74 ± 03) ns, τ(Tl) = (78 ± 03) ns

Ornithine decarboxylase and polyamines in liver and kidneys of rats on cyclical regimen of protein-free and protein-containing diets. Relationship to deoxyribonucleic acid synthesis in liver

Abstract: 1. The activity of ornithine decarboxylase in the liver and kidneys of rats maintained on a cyclical regimen of protein-free and protein-containing diets was investigated. There was a daily activation of the enzyme in response to the feeding of protein after 3 days feeding of protein-free diet. 2. The activation of ornithine decarboxylase in the liver and kidneys of rats re-fed on protein was demonstrable throughout 16 cycles of alternating 3-day periods of protein-free and protein-containing diets. The magnitude of the activation in the kidneys diminished from 20-fold stimulation in the first cycle to 5-fold stimulation (compared with animals fed with protein-free diet) in the later cycles of protein re-feeding. The activation of the enzyme in liver was decreased from 20-fold stimulation in the first cycle to approx. 10-fold stimulation in later cycles. 3. The concentration of spermidine was increased by approx. 50% in the liver of animals during cycling from protein-free to protein-containing diets. Spermine was unchanged, and putrescine was maintained at a low concentration approx. one-fifth to one-tenth that of spermidine after protein re-feeding. 4. The incorporation of [(3)H]thymidine into liver DNA was increased 10-fold in animals re-fed with protein compared with animals receiving protein-free diets. 5. The activation of ornithine decarboxylase by re-feeding of protein was inhibited 90% by the injection of propane-1,3-diamine during re-feeding. The stimulation of DNA synthesis was inhibited 60% by multiple injections of propane-1,3-diamine during the re-feeding of protein.

Hydrogen vs. deuterium transfer in asymmetric reductions: reduction of phenyl trifluoromethyl ketone by the chiral Grignard reagent from (S)-2-phenyl-1-bromoethane-1,1,2-d3

Abstract: An asymmetric reduction by a Grignard reagent is reported that is chiral by virtue of a hydrogen and deuterium disparity at the asymmetric ..beta..-carbon. (S)-PhCHDCD/sub 2/MgBr(5) not only reduces a prochiral ketone asymmetrically, but shows a higher asymmetric induction for deuterium transfer than for hydrogen transfer.