Showing papers by "University of New Mexico published in 1988"

Indices of landscape pattern

Abstract: Landscape ecology deals with the patterning of ecosystems in space. Methods are needed to quantify aspects of spatial pattern that can be correlated with ecological processes. The present paper develops three indices of pattern derived from information theory and fractal geometry. Using digitized maps, the indices are calculated for 94 quadrangles covering most of the eastern United States. The indices are shown to be reasonably independent of each other and to capture major features of landscape pattern. One of the indices, the fractal dimension, is shown to be correlated with the degree of human manipulation of the landscape.

Empowerment Education: Freire's Ideas Adapted to Health Education:

Abstract: Empowerment Education is proposed as an effective health education and prevention model that promotes health in all personal and social arenas. The model suggests that participation of people in group action and dialogue efforts directed at community targets enhances control and beliefs in ability to change people's own lives. The article is divided into three parts: a literature review demonstrating that powerlessness is linked to disease, and conversely, empowerment linked to health: an exposition of Brazilian educator Paulo Freire's empowering education theory with a comparison to traditional health education; and a case study of an empowering education substance abuse prevention project. The Alcohol and Substance Abuse Prevention (ASAP) Program is a University of New Mexico School of Medicine, Emergency Center, and community and school-based prevention project for adolescents. The case study will present ASAP's theoretical underpinnings and social practice, evaluation results, preliminary understandings of the stages for an empowering process, and future questions for practitioners interested in this approach. Empowerment education with its emphasis on organizing is recommended to be integrated into other prevention strategies of health promotion, disease prevention, and health policy.

Electrochemistry of Conductive Polymers III . Some Physical and Electrochemical Properties Observed from Electrochemically Grown Polyaniline

Abstract: Some of the physical and chemical properties of electrochemically grown polyaniline (PA) films have been studied and results are reported. Physical properties determined include the density of PA sulfate (1.5 g/cm3), empirical equations relating the film thickness with electrical charges measured during the film growth, cyclic voltammetric peak potentials, or the amount of benzoquinone recovered after the degradation reaction, and spectral absorptivity of reduced PA at its absorption band maximum ( depending on the medium). Elemental analysis results as well as stability factors determined during the potential cycling in various electrolyte solutions are presented as part of some chemical properties.

Motivational Interviewing with Problem Drinkers: II. The Drinker's Check-up as a Preventive Intervention

Abstract: Miller's (1983) system of ‘motivational interviewing’ is elaborated by providing a theoretical context for understanding its impact, with a summary of research on motivational interventions. An extension of this approach, the Drinker's Check-up (DCU), is described as a potential intervention for health screening, treatment selection and matching, cleint self-assessment, and research. Initial data from a sample of 42 problem drinkers receiving the DCU suggest that this intervention may increase help-seeking and modestly suppress alcohol consumption. This approach is interpreted within the broader context of research on minimal interventions for problem drinkers.

Economic and Political Explanations of Human Rights Violations

Abstract: G OVERNMENTS organize police forces and armies to protect their citizens, build schools and hospitals to educate and care for them, and provide financial assistance for the old and unemployed. But governments also kill, torture, and imprison their citizens. This dark side of government knows no geographic, economic, ideological, or political boundary. In the Middle East, for example, Iraq has morbidly placed a "welcome" doormat at the entrance to its torture chamber-a place where prisoners are burned with cigarettes and electric hot plates, where electric shocks are administered to them, and where they are hanged from the ceiling. In Central America, the government of Guatemala tolerates the torture and killing of three church workers who were assisting refugees. In Africa, the Cameroons allows eight prisoners to die of malnutrition; South Africa, through its policy of apartheid, systematically violates the rights of its nonwhite citizens. In Asia, Burmese army units operating in Karen state use local civilians as minesweepers. In Eastern Europe, the Soviet Union confines dissenters to psychiatric hospitals. In Western Europe, the residents of Northern Ireland are subjected to trials that fail to conform to international standards, and civilians are shot by the security forces.' The list goes on. Unfortunately, this type of governmental behavior is-even in the late 20th century-a dismal characteristic of contemporary politics. Most of the world's countries hold some "prisoners of conscience" or detain po-

Cooperative Hunting Harris' Hawks (Parabuteo unicinctus)

Abstract: Coordinated hunting by several individuals directed toward the capture and sharing of one Large prey animal has been documented convincingly only for a few mammalian carnivores. In New Mexico, Harris' hawks formed hunting parties of two to six individuals in the nonbreeding season. This behavior improved capture success and the average energy available per individual enabled hawks to dispatch prey larger than themselves. These patterns suggest that cooperation is important to understanding the evolution of complex social behavior in higher vertebrates and, specifically, that benefits derived from team hunting a key factor in the social living of Harris' hawks.

Resource utilization scales and landscape pattern

Abstract: The spatial patterning of resources constrains the movement of consumers on the landscape. Percolation theory predicts that an organism can move freely if its critical resource or habitat occupies 59.28% of the landscape. Sparse resources require an organism to operate on larger resource utilization scales. Multiple critical resources necessitate larger scales, while substitutable resources ease the scale requirements. Contagious spatial patterns require larger scales to permit movement between resource clusters. The study indicates a strong link between spatial pattern and ecological processes on a landscape.

Alpha-decay damage in minerals of the pyrochlore group

Abstract: X-ray diffraction analysis and transmission electron microscopy have been used to study the effects of alpha-decay damage in pyrochlore group minerals, characterized by the general formula A1−mB2O6(O,OH,F)1−n·pH2O. As defined by the XRD intensity ratio I/I0, both the saturation dose (for which I/I0=0.1−0.0) and the dose which signifies the initial loss of crystallinity (for which I/I0=1.0−0.8) increase as a function of geologic age. The increase is attributed to annealing of isolated alpha-recoil tracks back to the original crystalline structure. The tracks have calculated mean lives, τa, on the order of 108 years. In contrast, minerals which remain crystalline (e.g., uraninite, UO2) despite doses of up to 1018 alpha-events/mg have mean alpha-recoil track lives ≈104 years (Eyal and Fleischer 1985).

A NMR technique for the analysis of pore structure: Determination of continuous pore size distributions

Abstract: NMR measurements of the spin—lattice relaxation decay time for a fluid in a porous solid have been previously demonstrated as a significant tool for pore size/structure analysis. The analysis requires the solution of a Fredholm integral equation of the first kind to extract the desired T1, and therefore, pore size distribution from the relaxation measurements. Earlier work successfully used a nonnegative least-squares (NNLS) technique to solve this problem. However, for stability to be achieved with that approach, the problem must be significantly overconstrained (i.e., more relaxation measurements than pore size distribution points) which limits resolution. In addition, broad distributions are represented as several narrow peaks. In this work, the method of regularization is applied to extracting continuous pore volume distributions from relaxation measurements. The validity of the approach used to calculate the optimum value of the regularization smoothing parameter given an expected noise level and the data is demonstrated using “data sets” generated from known T1 distributions. Varying levels of random noise are added to these data sets and the T1 distribution is calculated for comparison to the starting distribution. For error levels in the range of 0.001 to 0.01, agreement between the starting and the calculated distributions is good. The method has also been applied to relaxation data obtained for water in several controlled pore glasses and “random packing of sphere” solids. Agreement to NMR/regularization and mercury porosimetry-derived pore size distributions was excellent with the only deviations being the result of porosimetry measuring pore neck size and NMR measuring the true pore volume to surface area ratio.

Autoantigenic germ cells exist outside the blood testis barrier.

Abstract: Preleptotene spermatocytes and spermatogonia are germ cells located outside the blood-testis barrier provided by the Sertoli cells. These cells have been found to express autoantigens accessible to circulating antibodies. Mice immunized with syngeneic testis with or without bacterial adjuvant had detectable IgG on cells at the periphery of seminiferous tubules. Sera from orchiectomized but not from testes-intact mice immunized with testis and adjuvants readily transferred similar IgG deposits to testes of normal recipients. When testis-specific antisera from orchiectomized mice and testis-intact mice were compared for their reactivity on prepuberal testicular cells, serum from orchiectomized donors had significantly higher reactivity. Ig was eluted from IgG-positive testes with acid buffer and was shown to be highly enriched in antibody to prepuberal testicular cells, confirming the Ag-specific nature of the IgG deposits. The testis IgG deposits reacted with antisera to IgG1 and IgG3 but not IgG2a or IgG2b. This finding can explain lack of association of C3 in the deposits. Only 30 to 40% of seminiferous tubules had IgG deposits and they coincided with stages 7 to 12 of the spermatogenic cycle. Thus, the expression of the autoantigens is stage specific. The in situ formation of immune complexes by circulating autoantibodies demonstrates conclusively that testis autoantigens are not completely sequestered, and the blood-testis barrier as an immunologic barrier is incomplete.

Electrochemistry of Conductive Polymers: IV Electrochemical Studies on Polyaniline Degradation — Product Identification and Coulometric Studies

Abstract: Electrochemical studies on the degradation reactions of oxidized polyaniline (PA) have been carried out to identify major soluble degradation products. As a result of spot tests as well as spectrophotometric experiments, p‐benzoquinone (BQ) was identified as a major degradation product. The overall number of electrons consumed per anilinium unit for the oxidation followed by degradation of PA was determined to be approximately two employing coulometric experiments. The yield for the BQ generation was close to 100% based on this number of electrons transferred. During the later stages of the degradation, the net hydrolysis rate follows first‐order kinetics and is a function of the film thickness. In addition, the hydrolysis reaction is shown to cease upon open circuit of the cell. Finally, a reaction mechanism which accounts for the observed behaviors is proposed.

Intrapopulation variation in predator-avoidance performance of Galápagos lava lizards: The interaction of sexual and natural selection

Abstract: The interaction of sexual and natural selection in shaping variation in defensive behavior was explored via three steps. (1) Three predictions from the hypothesis that varying responses to predation account for intrapopulation variation in locomotory performance and wariness were tested. One measure of locomotory performance and two measures of wariness were compared between lava lizards (Tropidurus albemarlensis) inhabiting sparsely (1% cover) and heavily (33% cover) vegetated areas of Isla Plaza Sur in the Galapagos Archipelago. (2) Variation in morphology was examined to identify proximate mechanisms for differences seen in (1). (3) Levels of predation were compared between males and females to test a prediction from a model explaining the observed variation in defensive behavior. Male, but not female, lizards from sparsely vegetated areas were faster than those from heavily vegetated areas. Both male and female lizards from sparsely vegetated areas were significantly warier than those from heavily vegetated areas. Multiple regression, covariance, and residual analyses identify relatively longer hindlimbs of males as the proximate cause of their greater speed over that of females, rather than differences in body size, but neither body nor hindlimb size account for the microgeographic differences in speed of males. Significantly higher predation on males provided a positive test of the major prediction from our model of selective forces in which sexual selection for territory defense by males favors short approach distances (by minimizing time away from the territory caused by erroneous flight) and leads to natural selection for their increased hindlimb size and speed.

Long-term acyclovir suppression of frequently recurring genital herpes simplex virus infection. A multicenter double-blind trial

Abstract: Normal adults with six or more episodes of genital herpes in the previous year were enrolled in a one-year, multicenter, double-blind trial comparing placebo with 400 mg of acyclovir administered orally twice daily. Patients with episodes during the study were offered 200 mg of acyclovir administered orally five times daily for five days; this allowed comparison of suppressive and episodic treatment. After one year, 227 (44%) of 519 patients receiving suppressive treatment and seven (2%) of 431 receiving placebo (episodic) treatment remained free of recurrences, and the mean numbers of recurrences per year were 1.8 and 11.4, respectively. Among 67 patients who had received suppressive therapy for one year, the mean duration of lesions in the first episode following the discontinuation of treatment was 9.3 days compared with 7.3 days among 45 patients who had received episodic therapy for one year. Treatment was well tolerated, and no changes were noted in the in vitro susceptibility to acyclovir of herpes simplex virus cultured during or after the one-year trial. Continuous or episodic oral acyclovir therapy for one year remained safe and effective. ( JAMA 1988;260:201-206)

Interferon effects upon the adenocarcinoma 38 and HL-60 cell lines: antiproliferative responses and synergistic interactions with halogenated pyrimidine antimetabolites.

Abstract: In order to gain insight into the mechanisms affecting combination treatment of tumor cells with interferon and halogenated pyrimidine antimetabolites, in vitro studies of murine colon adenocarcinoma 38 and HL-60 cell lines were undertaken. Interferons exhibited modest antiproliferative effects against these lines with DNA synthesis inhibited greater than RNA greater than protein synthesis, as studied by 3H-precursor incorporation. The adenocarcinoma cell line was considerably more sensitive to recombinant gamma-than to purified alpha/beta-interferon, while HL-60 was slightly more sensitive, in short term studies, to antiproliferative effects of recombinant alpha- than to gamma-interferon. Interferon treatment was further associated with suppression of a hyperdiploid component of the adenocarcinoma cell line, as detected by flow cytometry. Combination treatment of the adenocarcinoma cell line with interferon and halogenated pyrimidines, under 4-day continuous exposure conditions, revealed significant synergy for growth inhibition with gamma- much greater than alpha/beta-interferon and with 5-fluorodeoxyuridine greater than 5-fluorouracil much greater than 5-fluorouridine. Thus, synergy was much greater with the more antiproliferative interferon and with the antimetabolite derivative most likely to lead to thymidylate synthetase inhibition rather than RNA incorporation. Sequential 2-day + 2-day treatment revealed greater synergy when interferon preceded 5-fluorouracil or 5-fluorodeoxyuridine rather than the reverse protocol. The synergy of gamma-interferon and 5-fluorodeoxyuridine could be blocked by thymidine, which bypasses inhibition of thymidylate synthetase. HL-60 also exhibited thymidine antagonized synergistic growth-inhibitory effects of interferon and 5-fluorouracil. Analysis of this interaction by [3H]thymidine incorporation, which can reflect thymidylate synthase inhibition, revealed exaggerated responses of interferon-treated cells to either 5-fluorouracil or 5-fluorodeoxyuridine. These results indicate that interferon-halogenated pyrimidine antimetabolite synergistic interactions may be common to several cell types. Evidence is further presented for a mechanism of synergy entailing enhanced thymidylate synthetase inhibition by the antimetabolite of interferon-treated cells.

Social cognitions about adult male victims of female sexual assault

Abstract: Although men are far less likely than women to be victims of heterosexual assault, such cases have been reported with increasing frequency in recent years. We compared social judgments about male and female victims of heterosexual and homosexual rape and tested hypotheses concerning social cognitions that are assumed to underlie a male rape mythology. In a 2 × 2 × 2 design, 77 male and 89 female subjects made a series of judgments about a sexual assault case in which sex of victim and sex of assailants were manipulated. Consistent with the hypotheses, the male victim of sexual assault by females was judged more likely to have initiated or encouraged the sex acts, and more enjoyment and less stress were attributed to him. This pattern of results was more pronounced among male subjects. The results are discussed in relation to stereotypic beliefs concerning male sex roles, sexual motivation, and sexual functioning that are likely to affect the social cognitions of both observers and male victims of heterosexual assault.

Body composition response to exogenous GH during training in highly conditioned adults

Abstract: The effects of biosynthetic methionyl-human growth hormone (met-hGH) on body composition and endogenous secretion of growth hormone (GH) and insulin-like growth factor I (IGF-I) were studied in eight well-trained exercising adults between 22 and 33 yr of age. By the use of double-blind procedures, met-hGH (2.67 mg/0.5 ml diluent, 3 days/wk) and bacteriostatic water (placebo, 0.5 ml, 3 days/wk) were administered in a repeated-measures design that counterbalanced treatment order. Duration of each treatment was 6 wk. Subjects trained with progressive resistance exercise throughout and were maintained on a high-protein diet monitored by extensive compositional analyses of daily dietary intake records. Hydrodensitometry revealed that met-hGH significantly decreased percent body fat (%fat) and increased fat-free weight (FFW) and FFW/fat weight (FW), whereas the placebo treatment did not change any of these measures. Changes in FFW/FW correlated with the relative dose of met-hGH but did not correlate with either the peak GH response to L-dopa/arginine stimulation or IGF-I levels obtained after treatment with placebo. There were no differences between treatments in the dietary intakes of total kilocalories, protein, carbohydrates, and fat. Mean IGF-I levels were elevated after treatment with met-hGH compared with postplacebo levels. After treatment with met-hGH, five of seven subjects had a suppressed GH response to stimulation from either L-dopa/arginine or submaximal exercise. We conclude that supraphysiological doses of met-hGH will alter body composition in exercising adults in a relative dose-dependent manner and that such treatment may suppress endogenous release of GH in some individuals.

Cast brace treatment of proximal tibia fractures. A ten-year follow-up study.

Abstract: The long-term outcome of tibial plateau fractures treated by cast bracing was observed in 29 patients sustaining 30 tibial plateau fractures more than ten years after injury. Clinical and roentgenographic evaluation was performed and showed 61% good results overall. Range of motion averaged 117 degrees. Iowa knee score averaged 71 of 100 possible points. Thirty-two percent of the patients developed moderate or severe roentgenographic posttraumatic degenerative arthritis. Minimally displaced fractures were observed to do very well clinically without roentgenographic evidence of degenerative joint disease after a ten-year follow-up period. Seventy percent of displaced bicondylar fractures developed degenerative joint disease in clinical and roentgenographic evaluation. Cast bracing of minimally displaced fractures gave satisfactory results, whereas cast bracing of more complex fractures produced variable functional results.

Differentiation of human tumors from nonmalignant tissue by natural‐abundance 13C NMR spectroscopy

Abstract: High-quality, high-resolution, proton-decoupled natural-abundance 13C NMR spectra have been obtained in vitro at 1006 MHz from unprocessed human pathology specimens of tumors and adjacent nonneoplastic control tissues from lung, colon, and prostate In these preliminary studies, specific molecular parameters were identified from the spectra that distinguished neoplastic from nonneoplastic tissue of a given organ in all sites studied The NMR results were congruent with data derived from histochemical and biochemical examinations of the tissues and with previous studies using non-NMR methods In particular, a comparison of the spectra of prostatic adenocarcinoma with that of adjacent hyperplastic tissue revealed the following differences: The tumors contained (1) larger amounts of triacylglycerols, (2) smaller amounts of citrate, and (3) acidic mucins These transformation-associated deviations from the normally high amounts of citrate and low amounts of lipids in the prostate are consistent with an alteration in either the concentration or the activity of ATP-citrate lyase in the tumors The 13C NMR spectra of colonic adenocarcinoma tissue showed that this tumor type contained (1) smaller signals from triacylglycerols, (2) larger signals from phospholipids and lactate, and (3) decreased lipid fatty acyl chain saturation, when compared to spectra from adjacent normal colon Colloid carcinoma, another variant of colonic carcinoma, showed prominent 13C resonances from glycoproteins, which were absent from the spectra of normal colon, and from spectra from the more common pattern of colonic adenocarcinoma Smaller 13C NMR signals from mucins and other proteins, and the presence of triacylglycerol signals distinguished poorly differentiated lung carcinoma and from nonmalignant lung tissue These results indicate that natural-abundance 13C NMR spectroscopy may constitute a unique, nondestructive method, for the simultaneous measurement of a large number of tissue metabolites and structural components of significance to the study and diagnosis of a wide range of human tumors

Direct cardiac effects of vasopressin: role of V1- and V2-vasopressinergic receptors.

Abstract: Experiments were performed to determine the possible direct effects of arginine vasopressin (AVP) on cardiac function in the nonworking Langendorff preparation. Hearts were isolated from male Wistar rats, and the coronary arteries were retrograde perfused at a constant rate through the aorta with a Krebs-Henseleit solution, which was continuously bubbled with 95% O2-5% CO2. The hearts were paced at 280 beats/min and measurements made of peak ventricular pressure (PVP), first derivative of left ventricular pressure (dP/dtmax), and coronary perfusion pressure (CPP). By maintaining constant coronary flow, the direct cardiac effects of AVP could be determined independent of changes in myocardial O2 delivery elicited by potential coronary vasoconstriction. Myocardial function was assessed at AVP concentrations of 0, 10, 25, 50, 100, 200, 400, and 500 pg/ml. Progressive coronary vasoconstriction was observed with increasing AVP concentration. In contrast, PVP and dP/dtmax increased at 50 and 100 pg/ml of AVP but fell at 400 and 500 pg/ml. The maximal PVP and dP/dtmax responses were at 50 pg/ml (+16 +/- 3 and +44 +/- 4%, respectively), whereas at 500 pg/ml both PVP and dP/dtmax were reduced below control (-30 +/- 4 and -34 +/- 5%, respectively). Pretreatment with the specific V1-vasopressinergic antagonist d(CH2)5Tyr(Me)AVP (40 ng/ml) totally blocked both the coronary vasoconstrictor and contractility responses to AVP. Furthermore, infusion of a specific V2-agonist was without effect even at high doses. These data suggest that although AVP causes dose-related coronary vasoconstriction over a wide range of AVP concentrations, the hormone may exert a positive inotropic effect at doses mimicking circulating levels encountered in a number of pathophysiological situations.(ABSTRACT TRUNCATED AT 250 WORDS)