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Showing papers by "University of New Mexico published in 1981"


Journal ArticleDOI
TL;DR: Assessment of urethral function showed 36 patients (86 per cent) with an open vesical outlet and nonfunctional proximal urethra and 7 of 42 patients had reflex detrusor activity: 4 with coordinated micturition and 3 withdetrusor-sphincter dyssynergia.

958 citations


Journal ArticleDOI
TL;DR: A method for producing graded and reproducible focal cortical contusions in the rat is described and this lysosomal enzyme may participate in autolysis and development of focal cavitation following cortical contusion.

669 citations


Book
01 Jan 1981
TL;DR: In this article, the authors discuss the origins of European and Colonial origins and the Anglo-Saxons' political ideology, including the Mexican War and the Dissemination of Scientific Racial Nationalism.
Abstract: Introduction I. European and Colonial Origins 1. Liberty and the Anglo-Saxons 2. Aryans Follow the Sun 3. Science and Inequality 4. Racial Anglo-Saxonism in England II. American Destiny 5. Providential Nation 6. The Other Americans 7. Superior and Inferior Races 8. The Dissemination of Scientific Racialism 9. Romantic Racial Nationalism III. An Anglo-Saxon Political Ideology 10. Racial Destiny and the Indians 11. Anglo-Saxons and Mexicans 12. Race, Expansion, and the Mexican War 13. A Confused Minority 14. Expansion and World Mission Conclusion Notes Index

520 citations


Journal ArticleDOI
TL;DR: Life events reported to have occurred 6 months before the onset of illness were compared in 40 outpatients who had a first episode of primary depression and a matched normal control group, consistent with the view that certain recent life events play a substantial role as precipitants in some depressed patients.

336 citations


Journal ArticleDOI
TL;DR: A petrographic survey of > 1600 chondrules in thin-sections of 12 different mildly to highly unequilibrated H-, L-, and LL-chondrites, as well as morphological and textural study of 141 whole chond rules separated from 11 of the same chondrites was used to determine the relative abundances of definable chondrule primary textural types as discussed by the authors.
Abstract: A petrographic survey of > 1600 chondrules in thin-sections of 12 different mildly to highly unequilibrated H-, L-, and LL-chondrites, as well as morphological and textural study of 141 whole chondrules separated from 11 of the same chondrites, was used to determine the relative abundances of definable chondrule primary textural types Percentage abundances of various chondrule types are remarkably similar in all chondrites studied and are ∼ 47–52 porphyritic olivine-pyroxene (POP), 15–27 porphyritic olivine (PO), 9–11 porphyritic pyroxene (PP), 3–4 barred olivine (BO), 7–9 radial pyroxene (RP), 2–5 granular olivine-pyroxene (GOP), 3–5 cryptocrystalline (C), and ≤ 1 metallic (M) Neither chondrule size nor shape is strongly correlated with textural type Compound and cratered chondrules, which are interpreted as products of collisions between plastic chondrules, comprise ∼ 2–28% of nonporphyritic (RP, GOP, C) but only ∼ 2–9% of porphyritic (POP, PO, PP, BO) chondrules, leading to a model-dependent implication that nonporphyritic chondrules evolved at number densities (chondrules per unit volume of space) which were 102 to 104 times greater than those which prevailed during porphyritic chondrule formation (total range of ∼ 1 to ∼ 106 m−3) Distinctive “rims” of fine-grained sulfides and/or silicates occur on both porphyritic and nonporphyritic types and appear to post-date chondrule formation Apparently, either the same process(es) contributed chondrules to all unequilibrated ordinary chondrites or, if genetically different, the various chondrule types were well mixed before incorporation into chondrites Melting of pre-existing materials is the mechanism favored for chondrule formation

273 citations


Journal ArticleDOI
14 Aug 1981-Science
TL;DR: Male Mormon crickets produce a large spermatophore that the female eats, and males reject most receptive females as mates, and those accepted are more fecund than rejected individuals.
Abstract: Male Mormon crickets produce a large spermatophore that the female eats. Spermatophore proteins are important to female reproduction, and females compete for access to singing males. Males reject most receptive females as mates, and those accepted are more fecund than rejected individuals. This role reversal in courtship is in contrast to the behavior of the sexes in katydid species in which the males produce small spermatophores.

266 citations


Journal ArticleDOI
TL;DR: The fine-grained, opaque, silicate matrix of type 3 unequilibrated chondrites was examined by optical microscopy, an electron microprobe, and a scanning electron microscope as mentioned in this paper.

225 citations


Journal ArticleDOI
TL;DR: This method was suitable for all cell types analyzed, including mouse, human and rat lymphoid cells, erythrocytes and transformed cell lines, and could prove useful to those who work with in vivo derived specimens or have limited access to flow cytometry facilities.

215 citations


Journal ArticleDOI
01 Jul 1981-The Auk
TL;DR: Hoffman et al. as discussed by the authors classified seabird feeding flocks into three types on the bases of flock size and longevity and the nature of the food source: small, short-lived flocks over tightly clumped prey are called Type I; larger (5,000+ individuals), longer-lasting flock over less tightly clumping and less reactive prey is called Type II; Type III flocks form where zooplankton and other organisms are concentrated by downwelling.
Abstract: --Seabirds commonly gather into mixed-species flocks to feed on fish schools and other concentrations of prey. We group Alaskan and Washington seabird feeding flocks into three types on the bases of flock size and longevity and the nature of the food source. Small, short-lived flocks over tightly clumped prey are called Type I; larger (5,000+ individuals), longer-lasting flocks over less tightly clumped and less reactive prey are called Type II; Type III flocks form where zooplankton and other organisms are concentrated by downwelling. Birds participating in the flocks are assigned to four functional groups (some species fit into two groups): catalysts (larids and shearwaters) are highly visible birds that other birds watch and follow to food sources; divers (alcids, loons, cormorants) exploit the food sources underwater by pursuit diving; kleptoparasites (jaegers and gulls) steal food from other flock members; and suppressors (shearwaters and cormorants) interfere behaviorally with the feeding of other flock members by reducing the effective prey availability. Most flocks occurred within a few kilometers of shore. Type I flocks on the Washington coast averaged larger, lasted longer, and contained more species than Alaskan Type I flocks. The Washington and Alaska flocks contained about the same number of locally breeding species, but the Washington flocks also contained several migrant species that breed elsewhere in North America. Both contained shearwaters, migrants from the southern hemisphere, but the shearwaters were much more important in the Alaskan flocks. Black-legged Kittiwakes and shearwaters (catalysts) initiated most Alaskan flocks and were important in the development of flocks initiated by other birds. Once a flock was initiated, it grew until the food source became unavailable or until the local pool of prospective flock members was exhausted. The divers were able to discriminate from considerable distances between kittiwakes feeding on single fish and kittiwakes feeding on fish schools and approached only the latter. The various species tended to occupy characteristic positions within Type I flocks. Gulls and kittiwakes were central, and the various divers took peripheral positions. Kleptoparasitism by jaegers did not appear to influence Type I flock organization. Shearwaters, the most important suppressors, sometimes pursuit-plunged into fish schools and euphausiid shoals in such numbers that the prey concentrations were drastically reduced, scattered, or driven downward in seconds, and other birds were then unable to feed. Type II flocks were divisible into two groups, one consisting largely of kittiwakes and shearwaters and feeding on capelin, and the other dominated by shearwaters and feeding on pelagic crustaceans. Kleptoparasitism by Pomafine Jaegers in the capelin-based Type II flocks was frequent and differed from the kleptoparasitism of solitary birds in that the jaegers preferentially attacked birds carrying fish in their bills. Suppression appeared unimportant in capelin-based Type II flocks but probably kept alcids and gulls from joining the crustacean-based flocks. In some island groups Type III flocks occurred daily. They were less regular in structure and composition than Type I or Type II flocks. Kleptoparasitism by gulls and kittiwakes tended to keep puffins and other alcids on the edges of the flocks. The alcids' underwater approaches to the fish schools from the sides may have tended to keep the schools compact and near the surface. It has been hypothesized that the 437 The Auk 98: 437-456. July 1981 438 HOFFMAN, HEINEMANN, AND WIENS [Auk, Vol. 98 antipredator function of schooling by baitfish involves predator satiation and the difficulty of locating schools. Schooling does not function as. a deterrent to aerial predators in the same way that it does to swimming ones, however. Either birds are less important as predators, or schooling confers a different advantage in escaping aerial predation. Apparently, fish schools can escape rather quickly from bird flocks by descending away from the surface out of visual contact. Received 8 January 1980, accepted 12 February 1981. FISH-EATING and other seabirds in most of the world's oceans exploit fish schools and other clumped food sources in multispecies flocks. These flocks often include several species that feed differently (Gould 1971, Scott 1973, Sealy 1973) but sometimes in a complementary manner. If indeed the birds use complementary tactics when feeding together, the assemblages may be tightly interacting, coevolved systems. We studied the arian communities of the temperate and subarctic northeast Pacific Ocean to discern how intense, consistent, and obligatory such feeding interactions are. We surveyed the geographic and hydrographic distributions of flocks in our study areas and characterized them by structure, species composition, and food

199 citations


Journal ArticleDOI
TL;DR: If the traditional belief is correct that significant spontaneous recovery is complete by three to six months postonset, significant improvement in both groups beyond 26 weeksPostonset indicates both individual and group treatment are efficacious methods for managing aphasic patients.
Abstract: Five Veterans Administration Medical Centers participated in an investigation designed to compare individual with group treatment for aphasic patients who had suffered a left hemisphere cerebral vascular accident. Patients who met selection criteria were assigned randomly to either traditional, individual, stimulus-response type treatment of specific language deficits or group therapy designed to improve communication through group interaction and discussion with no direct treatment of specific language deficits. All patients received eight hours of therapy each week beginning at four weeks postonset and continuing until 48 weeks postonset or until they dropped out of the study. A battery of language measures and a clinical neurologic evaluation were administered at intake and every 11 weeks a patient was in the study. Results show both individually and group-treated patients made significant improvement in language abilities. Individual treatment resulted in significantly better overall performance on th...

195 citations


Journal ArticleDOI
TL;DR: The hypothesis that the tasks which require greater sensory-motor interaction require more neural control and are more likely to be disrupted after brain damage, regardless of lateralization is best explained.

Journal ArticleDOI
TL;DR: The adaptive delay algorithm uses a gradient technique to find the value of the adaptive delay that minimizes the mean-squared (MS) error function, which is a function of the power of the input signal.
Abstract: An adaptive technique is developed which iteratively determines the time delay between two sampled signals that are highly correlated. Although the procedure does not require a priori information on the input signals, it does require that the signals have a unimodal or periodically unimodal cross-correlation function. The adaptive delay algorithm uses a gradient technique to find the value of the adaptive delay that minimizes the mean-squared (MS) error function. This iterative algorithm is similar to the adaptive filter coefficient algorithm developed by Widrow. However, the MS error function for the adaptive delay is not quadratic, as it is in the adaptive filter. A statistical analysis determines the value of the convergence parameter which effects rapid convergence of the adaptive delay. This convergence parameter is a function of the power of the input signal. Computer simulations are presented which verify that the adaptive delay correctly estimates the time delay difference between two sinusoids, including those in noisy environments. The adaptive delay is also shown to perform correctly in a time delay tracking application.

Journal ArticleDOI
TL;DR: In this article, the authors tested three competing models of police decisions: the legal model suggests that police do not discriminate between victims on the basis of extralegal attributes; the extralega-al model suggests police do discriminate; and the change model suggests reliance on extralegal determinants declines with growing awareness of rape as a social problem.
Abstract: Responsibility for arrest and charging makes police influential agents in the offical processing of sexual-assault cases. Recent research offers three competing models of police decisions: the legal model suggests that police do not discriminate between victims on the basis of extralegal attributes; the extralegal model suggests that police do discriminate; and the change model suggests that reliance on extralegal determinants declines with growing awareness of rape as a social problem. These models were tested on 905 sexual-assault complaints to police in a large, midwestern city over six years. The data showed that the most important determinants of arrest, charge seriousness and felony screening were legal. Suspects received more serious outcomes when: (1) the victim was able to identify a suspect, (2) the victim was willing to testify, (3) the incident included sexual penetration, (4) charges were more serious, and (5) the incident included a weapon. Extralegal variables had less effect than legal variables on all three police decisions. Also, reorganization of the police department did not change arrest and felony filing rates or, for the most part, criteria used for making processing decisions.

Journal ArticleDOI
TL;DR: In this article, the effects of experimentally induced mood states on recall and chunking of letter sequences were examined in two experiments, focusing on the role of depressed mood induction on recall, the interaction between mood and varied versus repetitious spatial groupings of word sequences, and transfer of coding strategies.

Journal ArticleDOI
01 Feb 1981-Icarus
TL;DR: In this paper, a mechanism for the formation of Martian soil based on a palagonite model was proposed, which is a good analog to the soil of Mars to the level of precision available from Viking and ground-based telescopic spectral measurements.

Journal ArticleDOI
TL;DR: It is observed that the THE AUTHORS HI-55, WEHI-259, and CH5 B cell lymphomas express high levels of the Lyt-1 antigen, as detected by monoclonal antibodies using the fluorescence activated cell sorter.
Abstract: Although the Lyt-1 antigen has previously been considered a T cell-specific marker, recent evidence suggests that a population of Thy-1-, Lyt-1+ cells exists in normal lymphoid tissues. In this study, we have observed that the WEHI-55, WEHI-259, and CH5 B cell lymphomas express high levels of the Lyt-1 antigen, as detected by monoclonal antibodies using the fluorescence activated cell sorter. Three other B cell lymphomas of the 11 examined also gave weak but detectable reactions with the anti Lyt-1 monoclonal antibody. Except for the expression of the Lyt-1 antigen, these lymphomas are typical of cells in the B cell lineage with respect to surface phenotype. The Lyt-1 glycoprotein immunoprecipitated from metabolically labeled WEHI-55 cells is similar in structure to the Lyt-1 glycoprotein on thymocytes. These findings are similar to recent reports that B-type human lymphocytic leukemia cells express the putative human homologue of Lyt-1, the Leu-1 antigen.

Journal ArticleDOI
TL;DR: A cluster analysis procedure was used to identify subgroups of children who manifested specific learning disabilities in reading (SLD/R) in terms of performance on a battery of eight language and perceptual tests, finding some significant differences in measures of oral reading and reading comprehension skills.
Abstract: A cluster analysis procedure was used to identify subgroups of children who manifested specific learning disabilities in reading (SLD/R) in terms of performance on a battery of eight language and perceptual tests. Subjects included a group of 100 SLD/R children and 50 normal readers (NR). Six SLD/R subgroups were identified. All subgroups were both significantly different from one another as well as significantly different from the NR group's performance on the diagnostic battery. In addition, some significant differences were found among the six subgroups on measures of oral reading and reading comprehension skills. These results were compared with those of previous studies, none of which employed samples of the SLD/R youngsters identified in public schools. Results also were examined for their implications for a more precise match between the SLD/R learner characteristics and type of teaching method or material.

Journal ArticleDOI
TL;DR: Contrary to expectations, there were no significant differences on outcome measures between groups and results are interpreted within a self-control framework.
Abstract: Thrity-one self-referred problem drinkers were randomly assigned to one of two modalities for behavioral self-control training with a goal of moderation: (1) minimal therapist contact, in which clients worked only with a self-help manual; and (2) therapist directed training, in which clients received self-help materials plus 10 individual treatment sessions. Both groups showed significant reductions in alcohol consumption and peak blood alcohol concentration. Contrary to expectations, there were no significant differences on outcome measures between groups. Results are interpreted within a self-control framework.

Journal ArticleDOI
TL;DR: It is hypothesize that intratroop social competition limits population growth by regulating subadult survival rates during food scarcity cycles during food scarce cycles, and suggests a less drastic limiting mechanism.
Abstract: Chronological ages of Alouattaon Barro Colorado Island (BCI) were estimated from longitudinal dental wear. Combining these data with visual censuses, we approximated the study population’s age profile. A stable model was then constructed; from it we derived agespecific mortality rates. Mortality of immature animals is high, with 88% of the males and 65% of the females dying before 5 years. Adult mortality is low until 11 years, when it accelerates. The average adult life span is 16.6 years for males and 15.5 for females. The maximum life span is over 20 years. A pubertal male growth spurt occurs from 3 to 5 years, at which time females are primiparous. Sexual size differences develop primarily during this time. The 1976 age profile had anomalously few animals aged 7 years and males aged 8–9 and 15–16 years. With corroborating evidence, we hypothesize that these deficits resulted from excessive rainfall in 1963 and 1971, which reduced the fall fruit crop and led to a high juvenile mortality. Within half of our study troops, some adult males have nearly identical ages, suggesting an active process of agemate coalition. We hypothesize a form of kin selection, wherein peripheral male cohorts from the same natal troop have greater survival and social success than solitary animals. The stable model suggests an annual growth rate of 1.5% during the 1970s. Estimates of 16.7 and 4% for the previous two decades, following a yellow-fever epidemic, imply that the BCI population is becoming stationary. A very different age structure existed on neighboring Orchid Island in 1976, suggesting general food limitation. By contrast, the lowered, but continuing growth on BCI suggests a less drastic limiting mechanism. We hypothesize that intratroop social competition limits population growth by regulating subadult survival rates during food scarcity cycles.

Journal ArticleDOI
TL;DR: In the Acqumeh Indian world, there is an overtone that this is a Catholic Christian ritual celebration because of the significance of the saints' names and days on the Catholic calendar.
Abstract: Uncle Steve-Dzeerlai, which was his Acqumeh name-was not a literate man and he certainly was not literary. He is gone now, into the earth and back north as the Acqumeh people say, but I remember him clearly. He was a subsistence farmer, and he labored for the railroad during his working years; I remember him in his grimy working clothes. But I remember him most vividly as he sang and danced and told stories-not literary stories, mind you, but it was all literature nevertheless. On fiesta days, Steve wore a clean, good shirt and a bright purple or blue or red neckerchief knotted at his tightly buttoned shirt collar. Prancing and dipping, he would wave his beat-up hat, and he would holler, Juana, Juana! Or Pedro, Pedro! It would depend on which fiesta day it was, and other men and younger ones would follow his lead. Juana! Pedro! It was a joyous and vigorous sight to behold, Uncle Dzeerlai expressing his vitality from within the hold of our Acqumeh Indian world. There may be some question about why Uncle Steve was shouting Juana and Pedro, obviously Spanish names, non-Indian names. I will explain. In the summer months of June, July, and August, there are in the Pueblo Indian communities of New Mexico celebrations on Catholic saints' days. Persons whose names are particular saints' names honor those names by giving to the community and its people. In turn, the people honor those names by receiving. The persons named after the saints such as John or Peter-Juan, Pedro-throw from housetops gifts like bread, cookies, crackerjacks, washcloths, other things, and the people catching and receiving dance and holler the names. It will rain then and the earth will be sustained; it will be a community fulfilled in its most complete sense of giving and receiving, in one word: sharing. And in sharing, there is strength and continuance. But there is more than that here. Obviously, there is an overtone that this is a Catholic Christian ritual celebration because of the significance of the saints' names and days on the Catholic calendar. But just as obviously, when the celebration is held within the Acqumeh community, it is an AcquMELUS, Volume 8, No. 2, Summer 1981

Journal ArticleDOI
TL;DR: The studies demonstrate that intraperitoneal administration of insulin results in absorption of insulin which is volume, concentration, and time-dependent, and the peritoneal space may be an appropriate site for insulin delivery through a transcutaneous catheter.
Abstract: This study examined the relationship between the delivery of insulin into the peritoneal space and its absorption into the peripheral circulation. Studies were performed in conscious dogs receiving somatostatin (5.0 μg/min) to suppress endogenous insulin secretion, and intravenous glucose (50 mg/min) to prevent hypoglycemia. The biologic effectiveness of the absorbed insulin was determined by its hypoglycemic effect. The possibility of direct absorption of insulin into the portal circulation from the peritoneal space in anesthetized, portal vein-catheterized dogs was examined with radiolabeled I125 insulin. Our results suggest that absorption of insulin from the peritoneal space is volume, concentration, and time-dependent. Maximal absorption of insulin was observed at 50 min when 1.92 U of insulin in a volume of 3 ml was infused intraperitoneally over 30 min. More rapid absorption was observed at 30 min when this quantity of insulin was given in a 1-min intraperitoneal bolus, compared to 30 min of intraperitoneal infusion. Least rapid absorption of insulin followed the delivery of 1.92 U of insulin in a volume of 15 ml. Intermediate absorption of insulin was observed at 40 min when the 1.92 U was delivered in a volume of 0.6 ml. Peripheral intravenous insulin delivery of 1.92 U reached a maximal plasma concentration at 20 min, which was more than three times the concentration observed with intraperitoneal insulin. Isotopic tracer studies, in which radioiodinated insulin was placed into the peritoneal space in anesthetized dogs, demonstrated greater radioactivity in the portal vein than in the aorta throughout a 30-min observation period. These studies demonstrate that intraperitoneal administration of insulin results in absorption of insulin which is volume, concentration, and time-dependent. Thus, the peritoneal space may be an appropriate site for insulin delivery through a transcutaneous catheter.

Journal ArticleDOI
TL;DR: It is suggested that dual-frequency Duplex scanning with careful sample volume control and Doppler audio spectra/blood velocity waveform analysis can be used to characterize blood flow variables in normal and diseased human renal arteries.

Journal ArticleDOI
TL;DR: The high level of polyphagy on annuals and herbaceous perennials is suggested to be strongly influenced by the unpredictability of the host plant that is, in turn, controlled by environmental variability.
Abstract: Host plant preferences for 34 insect herbivore species are reported. Most polyphagous herbivores feeding on annuals, herbaceous perennials, and woody perennials show distinct preferences for the least abundant plant species among their various host plants. In addition, some populations of widely distributed polyphagous species are much more specialized in their diet than host plant lists alone would suggest. The high level of polyphagy on annuals and herbaceous perennials is suggested to be strongly influenced by the unpredictability of the host plant that is, in turn, controlled by environmental variability. Oligophagous herbivores preferred the least abundant woody perennials on the study sites. Ten of the 22 monophagous herbivores preferred the rarest of all the plant species on the same sites.

Journal ArticleDOI
TL;DR: In this paper, it was shown that scaling in the fragmentation region is valid up to the highest energies if (and only if) hadron-air inelastic cross sections continue to rise in the manner observed at lower energies.
Abstract: It is shown that evidence on cosmic-ray showers of energy 3\ifmmode\times\else\texttimes\fi{}${10}^{16}$ to ${10}^{20}$ eV indicates that scaling in the fragmentation region is valid up to the highest energies if (and only if) hadron-air inelastic cross sections continue to rise in the manner observed at lower energies. It is also shown, with use of additional air-shower evidence, that $〈\mathrm{ln} A〉$, the logarithmic mean primary mass number, changes from (4\ifmmode\pm\else\textpm\fi{}2) at 1.6\ifmmode\times\else\texttimes\fi{}${10}^{15}$ eV to (${0}_{\ensuremath{-}0}^{+0.6}$) at and above 3\ifmmode\times\else\texttimes\fi{}${10}^{16}$ eV.

Journal ArticleDOI
TL;DR: The spectra of RNA sequence isomers are very different, but that the spectra essentially do obey first‐neighbor relationships, and it appears that the Tm values of both DNAs and RNAs approximately obey first-neighbour relationships.
Abstract: We have synthesized and studied the CD spectra of five new double-stranded RNA polymers: poly[r(A-G)·r(C-U)], poly[r(A-U-C)·r(G-A-U)], poly[r(A-C-U)·r(A-G-U)], poly[r(A-A-C)·r(G-U-U)], and poly[r(A-C-C)·r(G-G-U)]. Together with previously published spectra of seven other RNA sequences, the spectra of these new sequences provide a library sufficient to approximate the spectra of all other RNA sequences by first-neighbor formulas and, in addition, give four spectra with which we may test the validity of first-neighbor approximations. (1) We find that the spectra of RNA sequence isomers are very different, but that the spectra essentially do obey first-neighbor relationships. (2) We have derived tentative first-neighbor assignments of negative bands at about 295 and 210 nm in the CD spectra. (3) A test of spectral independence shows that among the 12 polymer spectra there are at least seven significant independent spectral shapes, one less than the eight needed to give the most accurate spectral analysis of an unknown RNA sequence for its first-neighbor frequencies. (4) Spectra are calculated for RNAs of random base composition, approximating natural RNAs having complex sequences. (5) A T-matrix of spectral components assigned to the first-neighbor base pairs is derived from 10 of the spectra. This matrix allows an estimation of the CD spectrum of any other known RNA sequence or an analysis of the spectrum of an unknown sequence for its distribution of first-neighbor base-pair frequencies. (6) Test analyses of two of the synthetic polymers and of two natural RNAs set a probable limit on the accuracy of first-neighbor frequency determinations using this T-matrix. (7) Finally, we summarize in an appendix the melting temperatures for all the RNA and corresponding DNA sequences; it appears that the Tm values of both DNAs and RNAs approximately obey first-neighbor relationships.

Journal ArticleDOI
22 Jan 1981-Nature
TL;DR: The study of spontaneous autoimmunity in mouse models affords an opportunity to determine the cellular basis of the immune dysregulation observed in this disease, and establishes continuous cell lines from the lymph node cells of MRL/l mice, using techniques similar to those used to establish continuous lines of antigen-activated cytotoxic T cells and helper T-cell populations.
Abstract: The study of spontaneous autoimmunity in mouse models affords an opportunity to determine the cellular basis of the immune dysregulation observed in this disease. Recently, a new mouse strain, MRL/Mp-Ipr/Ipr (MRL/l) has been developed which carries an autosomal recessive gene (lpr) that results in massive lymph node enlargement concomitant with the development of several autoantibodies. The interest in this strain lies in the possibility that the defect in T-cell regulation of the immune response is manifested at a different level from that in the NZB mouse. It has been reported that the proliferating population of lymphoid cells in the nodes of these mice are T cells, but that many of them are devoid of Lyt surface antigens. We have accordingly initiated several lines of research with these mice, including quantitative flow cytometry characterization of Lyt antigen expression of cells in the lymph nodes of the mice. In an approach to isolate and study the properties of these cells, we have also established continuous cell lines from the lymph node cells of MRL/l mice, using techniques similar to those used to establish continuous lines of antigen-activated cytotoxic T cells and helper T-cell populations.

Journal ArticleDOI
24 Jul 1981-Science
TL;DR: The ground pattems found in Pulitrouser Swamp, northern Belize, are vestiges of raised and channelized fields, types of wetland cultivation used by the ancient Maya, which indicates that the large number of well-defined ground patterns reported in other areas in the central Maya lowlands are probably traces of Maya wetlands cultivation.
Abstract: The ground pattems found in Pulitrouser Swamp, northern Belize, are vestiges of raised and channelized fields, types of wetland cultivation used by the ancient Maya. This form of hydraulic cultivation was apparently employed sometime between 200 B.C. and A.D. 850. The environment of the swamp, the fields and canals, and one nearby settlement, Kokeal, are described. The evidence indicates that the large number of well-defined ground patterns reported in other areas in the central Maya lowlands are probably vestiges of Maya wetland cultivation.

Journal ArticleDOI
TL;DR: The conclusions are that the current widely accepted practice of prompt exploration on suspicion of appendicitis is fully justified, that the inflammation inappendicitis may have quite different rates of progression from patient to patient, and that the etiopathogenesis of appendectomy may not be uniform and in some cases may involve important immunologic factors.


Journal Article
TL;DR: This investigation emphasized the marked intratumor and intertumor heterogeneity that is observed when cloned cell lines are analyzed quantitatively for a large number of surface markers and may be particularly useful in defining heterogeneity in maturation states within cloned tumor cell lines.
Abstract: In this study, a large series of murine B lymphomas and plasmacytomas were examined by quantitative flow cytometry analysis using a panel of monoclonal antibodies against murine differentiation antigens. These cell lines appear to represent subpopulations of lymphoid cells arrested at distinct stages of differentiation. In general, the pattern of reactions of these monoclonal antibodies with the B cell neoplasms was comparable to the reactions seen with normal cells in the same lineage. The Thy-1.2, Lyt-2, and T-30 differentiation antigens were not detected on any B lymphoma or plasmacytoma. However, certain surface Ig-positive B lymphomas do express the Lyt-1 antigen. With respect to other differentiation markers examined, including E2, F1, ThB, Lgp-100 (Ly 9.1), G2, and T-200 (Ly 5), the reaction of the B cell tumors reflected the expression of these markers on comparable normal cells. This investigation also emphasized the marked intratumor and intertumor heterogeneity that is observed when cloned cell lines are analyzed quantitatively for a large number of surface markers. Thus, this approach may be particularly useful in defining heterogeneity in maturation states within cloned tumor cell lines.