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There are minimal data characterizing the trajectory of left heart growth and hemodynamics following fetal aortic valvuloplasty (FAV).This retrospective study included patients who underwent FAV between 2000 and 2019, with echocardiograms performed pre-FAV, immediately post-FAV, and in late gestation.Of 118 fetuses undergoing FAV, 106 (90%) underwent technically successful FAV, of which 55 (52%) had biventricular circulation. Technically successful FAV was associated with improved aortic valve growth (p 0.001), sustained antegrade aortic arch (AoA) flow (p = 0.02), improved mitral valve (MV) inflow pattern (p = 0.002), and favorable patent foramen ovale (PFO) flow pattern (p = 0.004) from pre-FAV to late gestation. Compared to patients with univentricular outcome, patients with biventricular outcome had less decrement in size of the left ventricle (LV) (p 0.001) and aortic valve (p = 0.005), as well as more physiologic PFO flow (p 0.001) and antegrade AoA flow (p 0.001) from pre-FAV to late gestation. In multivariable analysis, echocardiographic predictors of biventricular outcome were less decline in LV end diastolic dimension (p 0.001), improved PFO flow (p = 0.004), and sustained antegrade AoA flow (p = 0.002) from pre-FAV to late gestation.Stabilization of left heart growth and improved hemodynamics following successful FAV through late gestation are associated with postnatal biventricular circulation.

Objectives Integration of HIV care with general healthcare may improve patient engagement. We assessed patient outcomes in four clinics offering HIV care integrated into primary care clinics in Yangon, Myanmar. Methods We carried out a retrospective cohort analysis of 4551 patients who started antiretroviral therapy between 2009 and 2017. Mortality and disengagement from care were assessed using Cox regression. Results People living with HIV presented late with low CD4 counts [median (25th, 75th percentile) = 178 (65, 308) from 4216 patients] and advanced HIV (69% with stage 3 or 4). Survival was 0.95 at 1 year and 0.90 at 5 years. Males were at a higher risk of mortality than females [unadjusted hazard ratio (uHR) = 1.6 (95% CI: 1.3–2.0). Patients linked to HIV care via antenatal care or partner/parent notification were at reduced risk of mortality [uHR = 0.4 (95% CI: 0.1–1.0) and uHR = 0.5 (95% CI: 0.3–0.7)] relative to patients who presented for HIV testing. The cumulative incidence of disengagement was 0.06 at 1 year and 0.15 at 5 years. Young adults had a higher risk of disengagement than did children and older patients. Women linked to HIV care via antenatal care services were at increased risk of disengagement relative to patients who came for HIV testing (uHR = 2.4; 95% CI: 1.7–3.4). Mortality and disengagement remained steady over calendar time as the programme scaled up. Conclusions HIV care within a primary care model is effective to attain early linkage to care, with high survival. However, close attention should be given to disengagement from care, in particular for pregnant women.

Background RSV is a leading cause of lower respiratory tract infection in infants. Monitoring RSV glycoprotein sequences is critical for understanding RSV epidemiology and viral antigenicity in the effort to develop anti‐RSV prophylactics and therapeutics. Objectives The objective is to characterize the circulating RSV strains collected from infants in South Africa during 2015‐2017. Methods A subset of 150 RSV‐positive samples obtained in South Africa from HIV‐unexposed and HIV‐exposed‐uninfected infants from 2015 to 2017, were selected for high‐throughput next‐generation sequencing of the RSV F and G glycoprotein genes. The RSV G and F sequences were analyzed by a bioinformatic pipeline and compared to the USA samples from the same three‐year period. Results Both RSV A and RSV B co‐circulated in South Africa during 2015‐2017, with a shift from RSV A (58%‐61% in 2015‐2016) to RSV B (69%) in 2017. RSV A ON1 and RSV B BA9 genotypes emerged as the most prevalent genotypes in 2017. Variations at the F protein antigenic sites were observed for both RSV A and B strains, with dominant changes (L172Q/S173L) at antigenic site V observed in RSV B strains. RSV A and B F protein sequences from South Africa were very similar to the USA isolates except for a higher rate of RSV A NA1 and RSV B BA10 genotypes in South Africa. Conclusion RSV G and F genes continue to evolve and exhibit both local and global circulation patterns in South Africa, supporting the need for continued national surveillance.

Evolutionary adaptation is the adjustment of species to a new or changing environment. Engaging in mutualistic microbial symbioses has been put forward as a key trait that promotes the differential, evolutionary success of many animal and plant lineages (McFall-Ngai, 2008). Microbial mutualists allow these organisms to occupy new ecological niches where they could not have persisted on their own or would have been constrained by competitors. Vertical transmission of beneficial microbial symbionts from parents to the offspring is expected to link the adaptive association between a given host and microbe, and it can lead to coevolution and sometimes even cospeciation (Fisher, Henry, Cornwallis, Kiers, & West, 2017). Vertical transmission also causes bottlenecks that strongly reduce the effective population size and genetic diversity of the symbiont population. Moreover, vertically transmitted symbionts are assumed to have fewer opportunities to exchange genes with relatives in the environment. In a "From the Cover" article in this issue of Molecular Ecology, Breusing, Johnson, Vrijenhoek, and Young (2019) investigated whether hybridization among different host species could lead to interspecies exchange of otherwise strictly vertically transmitted symbionts. Hybridization of divergent lineages can potentially cause intrinsic and extrinsic incompatibilities, swamp rare alleles, and lead to population extinctions. In some cases, however, it might also create novel trait combinations that lead to evolutionary innovation (Marques, Meier, & Seehausen, 2019). Breusing et al. (2019) linked the concept of hybridization to symbiont transmission, and their findings have significant implications for the study of evolution of vertically transmitted symbionts and their hosts.

The Sierra Nevada yellow‐legged frog (Rana sierrae) was once an abundant and widely distributed amphibian in California's alpine ranges. Rana sierrae is adapted to high‐elevation, fishless habitats. Its adaptions are reflected in a unique life cycle that involves a flexible, extended juvenile phase due to the short growing season typical of its alpine habitat. However, today this species is critically endangered, and most populations have been extirpated from their native range. Here, we present an 18‐yr‐long demographic study of a R. sierrae population in 15 lakes at Dusy Basin in Kings Canyon National Park. We focused on the period leading up to the arrival of the pathogenic chytrid fungus, Batrachochytrium dendrobatidis (Bd), and the subsequent local extinction of R. sierrae. We used N‐mixture abundance modeling, which accounts for detection probabilities, to quantify factors affecting frog abundance at different life stages. The abundance of subadult and adult frogs was negatively associated with the presence of introduced trout (Oncorhynchus mykiss and O. aquabonita). Frog abundance in all life stages was positively associated with lake surface area. The propensity of lakes drying correlated negatively with abundance of eggs, subadults, and adults in the following year. Moreover, drought years, characterized by longer summers and less winter snowpack, led to higher rates of lakes drying. Finally, our results suggest that the frequency of such droughts in the region has increased since 1937. Increased frequency or severity of droughts is expected to decrease the value of shallow lakes for Sierra Nevada yellow‐legged frogs because these habitats are prone to drying. We discuss our results in terms of future restoration strategies, including reintroduction and probiotic treatment, in this changed and changing ecosystem.

Recent studies found fish egg-specific bacterial communities that changed over the course of embryogenesis, suggesting an interaction between the developing host and its microbiota. Indeed, single-strain infections demonstrated that the virulence of opportunistic bacteria is influenced by environmental factors and host immune genes. However, the interplay between a fish embryo host and its microbiota has not been studied yet at the community level. In order to test whether host genetics affects the assemblage of egg-associated bacteria, adult brown trout (Salmo trutta) were sampled from a natural population. Their gametes were used for full-factorial in vitro fertilizations to separate sire from dam effects. In total 2,520 embryos were singly raised under experimental conditions that differently support microbial growth. High-throughput 16S rRNA amplicon sequencing was applied to characterize bacterial communities on milt and fertilized eggs across treatments. Dam and sire identity influenced embryo mortality, time until hatching, and composition of egg-associated microbiotas, but no link between bacterial communities on milt and on fertilized eggs could be found. Elevated resources increased embryo mortality and modified bacterial communities with a shift in their putative functional potential. Resource availability did not significantly affect any parental effects on embryo performance. Sire identity affected bacterial diversity that turned out to be a significant predictor of hatching time: embryos associated with high bacterial diversity hatched later. We conclude that both host genetics and the availability of resources define diversity and composition of egg-associated bacterial communities that then affect the life-history of their hosts. This article is protected by copyright. All rights reserved.

Dysfunctional glycinergic inhibitory transmission underlies the debilitating neurological condition, hyperekplexia, which is characterised by exaggerated startle reflexes, muscle hypertonia and apnoea. Here we investigated the N46K missense mutation in the GlyR α1 subunit gene found in the ethylnitrosourea (ENU) murine mutant, Nmf11, which causes reduced body size, evoked tremor, seizures, muscle stiffness, and morbidity by postnatal day 21. Introducing the N46K mutation into recombinant GlyR α1 homomeric receptors, expressed in HEK cells, reduced the potencies of glycine, β-alanine and taurine by 9-, 6- and 3-fold respectively, and that of the competitive antagonist strychnine by 15-fold. Replacing N46 with hydrophobic, charged or polar residues revealed that the amide moiety of asparagine was crucial for GlyR activation. Co-mutating N61, located on a neighbouring β loop to N46, rescued the wild-type phenotype depending on the amino acid charge. Single-channel recording identified that burst length for the N46K mutant was reduced and fast agonist application revealed faster glycine deactivation times for the N46K mutant compared with the WT receptor. Overall, these data are consistent with N46 ensuring correct alignment of the α1 subunit interface by interaction with juxtaposed residues to preserve the structural integrity of the glycine binding site. This represents a new mechanism by which GlyR dysfunction induces startle disease.

Ecological conditions can influence not only the expression of a phenotype, but also the heritability of a trait. As such, heritable variation for a trait needs to be studied across environments. We have investigated how pathogen challenge affects the expression of MHC genes in embryos of the lake whitefish Coregonus palaea. In order to experimentally separate paternal (i.e. genetic) from maternal and environmental effects, and determine whether and how stress affects the heritable variation for MHC expression, embryos were produced in full-factorial in vitro fertilizations, reared singly, and exposed at 208 degree days (late-eyed stage) to either one of two strains of Pseudomonas fluorescens that differ in their virulence characteristics (one increased mortality, while both delayed hatching time). Gene expression was assessed 48 h postinoculation, and virulence effects of the bacterial infection were monitored until hatching. We found no evidence of MHC class II expression at this stage of development. MHC class I expression was markedly down-regulated in reaction to both pseudomonads. While MHC expression could not be linked to embryo survival, the less the gene was expressed, the earlier the embryos hatched within each treatment group, possibly due to trade-offs between immune function and developmental rate or further factors that affect both hatching timing and MHC expression. We found significant additive genetic variance for MHC class I expression in some treatments. That is, changes in pathogen pressures could induce rapid evolution in MHC class I expression. However, we found no additive genetic variance in reaction norms in our study population.

The combination in advances in MALDI-TOF MS instrumentation(1) and serum sample preparation techniques,(2-4) has lead to the emergence of MALDI serum protein expression profiling as a promising tool for biomarker discovery.(5) However, three factors still pose significant challenges for MALDI profiling of serum: the limited mass window of MALDI, serum protein complexity,(6) and analytical reproducibility.(7, 8) MALDI has a small mass preference due to the ionization efficiency of intact protein molecules and the focusing of flight of ions towards the detector. In linear mode, TOF analyzers have limited sensitivity for masses above 20 kDa. To address this, we previously reported the enhancement of MALDI broad mass range detection of protein signals.(9) Spanning a 100 kDa mass range, we improved the sensitivity of detection by an order of magnitude through the combined optimization of sample preparation, instrument parameters and data processing procedures. The complexity of the blood proteome is very high, with protein concentrations differing by up to ten orders of magnitude.(10) This large dynamic range exceeds current proteomic analytical capabilities; thus analysis of easily prepared subproteomes of serum or plasma is essential. Here, we shift our focus back to the enhancement of MALDI analysis in the low mass regime. The low molecular weight (LMW) subcomponent of serum promises to be a rich source of undiscovered biomarkers, as biological processes give rise to a plethora of proteolytic protein fragments.(11) Currently, there is no consensus on what constitutes the mass limits of this derivative proteome (also termed peptidome). However, “

We observed Anopheles gambiae sensu stricto stocks that contained both Mopti (M) and Savanna (S) rDNA intergenic spacers (IGS). ASEMBO1 male IGS sequences consistently had a mixture. A diagnostic M and S Hha I restriction enzyme site in these fragments was concordant with two SNPs associated with M and S. Standard M and S stocks demonstrated X-chromosome-only inheritance of the rDNA form, but the ASEMBO1 males showed X and Y chromosome linkage of mixed rDNA. The metaphase Y chromosomes of ASEMBO1 contained a significantly larger amount of DNA relative to the X than a standard S stock. Analysis of wild A. gambiae males from the putative location of origin of the ASEMBO1 stock did not detect the same pattern of polymorphism observed in the laboratory stock but did detect heterogeneous arrays including some missing a diagnostic Hha I restriction site. These results demonstrate that M and S IGS types can occur within the rDNA arrays of a chromatid in laboratory A. gambiae stocks, and some A. gambiae s.s. have rDNA on the Y chromosome.

We present a mosquito marking technique suitable for mark-release-recapture that can be used with a hand-held, portable X-ray fluorescence (XRF) spectrometer, which is practical for field measurements. Third instar Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) and Anopheles stephensi Liston larvae were cultured to pupation in water containing rubidium (Rb) Cl at concentrations up to 1000 p.p.m. Rb. Anopheles gambiae larvae survived to adulthood at concentrations as high as 1000 p.p.m. Rb but suffered pupal mortality and reduced adult longevity at high concentrations. We were able to culture An. stephensi at Rb concentrations as high as 300 p.p.m. The presence of Rb in adults was evaluated using a portable XRF analyser, and we were able to reliably detect Rb above background levels in 10-day-old females and 4-day-old males at concentrations causing minimal pupal or adult mortality. We observed that Rb marking was not permanent, and the concentration declined significantly as adults aged. The low cost of labelling with RbCl and the field portability of the spectrometer provide a useful means for labelling mosquitoes via breeding sites or in the laboratory for mark-release-recapture experiments.

Regulation of GABAA receptors by extracellular pH exhibits a dependence on the receptor subunit composition. To date, the molecular mechanism responsible for the modulation of GABAA receptors at alkaline pH has remained elusive. We report here that the GABA-activated current can be potentiated at pH 8.4 for both αβ and αβγ subunit-containing receptors, but only at GABA concentrations below the EC40. Site-specific mutagenesis revealed that a single lysine residue, K279 in the β subunit TM2–TM3 linker, was critically important for alkaline pH to modulate the function of both α1β2 and α1β2γ2 receptors. The ability of low concentrations of GABA to reveal different pH titration profiles for GABAA receptors was also examined at acidic pH. At pH 6.4, GABA activation of αβγ receptors was enhanced at low GABA concentrations. This effect was ablated by the mutation H267A in the β subunit. Decreasing the pH further to 5.4 inhibited GABA responses via αβγ receptors, whereas those responses recorded from αβ receptors were potentiated. Inserting homologous β subunit residues into the γ2 subunit to recreate, in αβγ receptors, the proton modulatory profile of αβ receptors, established that in the presence of β2H267, the mutation γ2T294K was necessary to potentiate the GABA response at pH 5.4. This residue, T294, is homologous to K279 in the β subunit and suggests that a lysine at this position is an important residue for mediating the allosteric effects of both acidic and alkaline pH changes, rather than forming a direct site for protonation within the GABAA receptor.

Locational reasoning plays an important role in many applications of AI problem-solving systems, yet has remained a relatively unexplored area of research. This paper addresses both theoretical and practical issues relevant to reasoning about locations. We define several theories of location designed for use in various settings, along with a sound and complete belief revision calculus for each that maintains a STRIPS-style database of locational facts. Techniques for the efficient operationalization of the belief revision rules in planning frameworks are presented. These techniques were developed during application of the location theories to several large-scale planning tasks within the Sipe planning framework.

Recent reports indicate that vegetative growth and yield of C 3 crops are enhanced by foliar methanol application and that overall crop water use was reduced by methanol sprays. It has been suggested that methanol may act as a C source for the plant and a photorespiration inhibitor. Field experiments were conducted near Pendleton, OR, during 1993 and 1994 to determine if foliar methanol applications would increase crop growth and yield in the dryland agroecosystems common to the Pacific Northwest. Methanol solutions (200 or 400 mL L -1 with a surfactant) were applied to winter wheat (Triticum aestivum L.), spring wheat, spring barley (Hordeum vulgare L.) and pea (Pisum sativum L.) at several plant growth stages. Phytotoxic symptoms were observed only with the highest concentration of methanol. No significant response, either beneficial or detrimental, to methanol application was found in any crop. No differences were found in stomatal conductance or leaf specific weight between any methanol treatment and the controls. Methanol applications did not significantly increase crop growth or yield. We concluded that methanol applications will not benefit grain and pea production in the northwestern USA.

This essay evaluates the tribal-state compact process, as one of several alternative, nonadversarial processes, warranting attention. It argues that, because of its binding character and relatively low cost (in contrast to litigation), and because it is based in the idea of tribes and states exhibiting mutual respect, the compact process is an advanced version of negotiation and bargaining that tribes and states should consider where appropriate.

Conservation tillage systems, which leave residues on or near the soil surface, can suppress soft white winter wheat (Triticum aestivum L.) emergence, early development of seedlings, and grain yield. This field study evaluated effects of tillage, seed size, and seed density on the above parameters. Commercially processed, untreated «Stephens» winter wheat grains, separated into size-density combinations of large-dense, largelight, small-dense, small-light, and unsorted, were seeded into tilled and nontilled soil in the fall of 1990 and 1991. In 1990, when seed zone soil moisture was adequate, tillage significantly decreased seminal root intercepts at 3 cm (16%) and 5 cm (24%) below the seed. There was no significant effect of seed size-density [...]

Small-grain stand establishment in research plots of the summer rainfall region of South Africa is a problem because of dry surface soil. A vacuum system plot planter was developed to meet these requirements. The planter has simple adjustments for changes in species, cultivars, seeding ante, row spacing, and fertilizer rate. The precision planter has fertilizer times and modified planter units. Uniform stands are achieved with most species at seeding rates varying from 5 to 100 kg ha −1 (4.5-89.0 Ib acre −1 ), with no restriction in plot length. The unit is easily transported and can plant in excess of 80 5-m (16.5 ft) plots h −1 [...]

The sensitivity and specificity of nerve conduction studies (NCS's) and electromyography (EMG) for the diagnosis of carpal tunnel syndrome (CTS) were evaluated by a critical review of the literature. With a search of the medical literature in English through May 1991, 165 articles were identified and reviewed on the basis of six criteria of scientific methodology. The findings of 11 articles that met all six criteria and the results of 48 additional studies that met four or five criteria are presented. We concluded that median sensory and motor NCS's are valid and reproducible clinical laboratory studies that confirm a clinical diagnosis of CTS with a high degree of sensitivity and specificity. Clinical practice recommendations are made based on a comparison of the sensitivities of the several different median nerve conduction study (NCS) techniques.

1 We examined effects of bradykinin (BK) receptor antagonists on airway hyperresponsiveness and eosinophilia in sensitized guinea-pigs that had been administered single, as well as repeated (chronic) challenges with inhaled ovalbumin. In addition, the effects of BK antagonists on antigen-induced respiratory distress during the chronic study were noted. 2 At 24 h following single antigen challenge, guinea-pigs exhibited airway hyperresponsiveness to the bronchoconstrictor effect of i.v. histamine, characterized by a left shift in the dose-response curve. In addition, responses to the maximum dose of histamine that could be used were significantly increased in hyperresponsive guinea-pigs. The percentages of bronchoalveolar fluid, eosinophil and neutrophils also increased. 3 A BK B1 receptor antagonist, desArg9-[Leu8]-BK, significantly inhibited airway hyperresponsiveness induced by single antigen challenge. A B2 receptor antagonist, d-Arg-[Hyp3, Thi5,8,d-Phe7]-BK (NPC 349) had a small, but statistically significant inhibitory effect on responsiveness to the highest histamine dose in challenged animals. DesArg9-[Leu8]-BK significantly inhibited the neutrophilia, whereas NPC 349 inhibited infiltration by both cell types. 4 Chronic antigen challenge also caused airway hyperresponsiveness to i.v. acetylcholine (ACh), distinguished by an increase in the slope of the dose-response curve. Thus, the magnitude of the bronchoconstrictor responses to the maximum dose of ACh that could be used was significantly increased. No change in sensitivity to ACh was evident. Marked eosinophilia was also noted in the trachea, bronchi and lung parenchyma. 5 Airway hyperresponsiveness and eosinophilia, induced by chronic antigen challenge, were markedly inhibited by the B2 antagonists, d-Arg-[Hyp3,d-Phe7]-BK (NPC 567) or d-Arg-[Hyp3,Thi5d-Tic7,Tic8]-BK (NPC 16731). NPC 16731 also abolished antigen-induced cyanosis, and delayed the onset of dyspnoea, doubling the time taken for animals to exhibit respiratory distress. 6 The ability of BK receptor antagonists to inhibit antigen-induced airway hyperresponsiveness, in addition to eosinophilia, indicates an important role for endogenous kinins. Moreover, the abrogation of eosinophil infiltration suggests that BK has a significant function in maintaining allergic inflammation of the airways.

While there has been recent interest in research on planning and reasoning about actions, nearly all research results have been theoretical. We know of no previous examples of a planning system that has made a significant impact on a problem of practical importance. One of the primary goals during the development of the SIPE-2 planning system has been the balancing of efficiency with expressiveness and flexibility. With a major new extension, SIPE-2 has begun to address practical problems. This paper describes this new extension and the new applications of the planner. One of these applications is the problem of producing products from raw materials on process lines under production and resource constraints. This is a problem of commercial importance and SiPE-2's application to it is described in some detail. Bien que Ton ait constate recemment un interět pour la planification et le raisonnement a propos des actions, presque tous les resuhats des recherches sont theoriques. Nous ne connaissons pas d'exemple de systeme de planification qui ait eu une influence majeure dans la resolution d'un probleme de nature pratique. L'un des prihcipaux objectifs de l'elaboration du systeme de planification SIPE-2 a ete la recherche d'un equilibfe entre l'efficacite, l'expressivite et la flexibilitye. La capacitye du systeme SIPE-2 a ete augmentee considerablement afin qu'il puisse s'attaquer a la resolution de problemes de nature pratique. Cet article traite de 1'extension du systeme et des nouvelles applications du planificateur. L'une de ces nouvelles applications est relative au probleme de la production a la chaine de biens a partir de matieres premieres, en tenant compte de contraintes de production et de ressources. Ce probleme est d'une importance commerciale et l'application du systeme SIPE-2 a sa resolution est decrite avec plus ou moins de details.

Clearing. Path:Theorizing the Past in Native American Studies. Nancy Shoemaker, ed. New York: Routledge, 2002. 215 pp.

(...) Materials used are tape and waterproof marker. Individual plants or plant parts are placed on a strip of tape in the order in which they are analyzed. They can then be passed on to another evaluator for further analyses, retaining individual plant identity. This method doubles the number of plants processed/hour and reduces materials cost from approximately $0.13 to les than $0.01/plant

To test the assumption that negative attitudes toward various stigmatized groups are learned in early childhood, four scales of the semantic differential were employed to assess children's attitudes toward four groups (normals, crippled, retarded, and mentally ill) for both male and female third and sixth graders. The mentally ill were rated most negatively on both the Evaluation Scale and the Understandability Scale, but were rated comparable to normal people on Activity and Potency. Both the retarded and the crippled were rated less positively than normals on the Evaluation Scale, but not as negatively as the mentally ill. The retarded and the crippled were rated less Active and Potent than both normals and the mentally ill. No differences were found between the third and sixth graders on attitudes toward the three stigmatized groups. Implications for the “social labeling” theory of mental disorders are discussed.

Pacific ocean perch, Sebastes alutus, stocks in the northeastern Pacific Ocean off the coasts of Oregon, Washington, and British Columbia experienced severe damage from overexploitation in the mid-1960's. Catch limits were imposed during 1978. Fishermen questioned the need for these limitations on the basis of lack of precision in biomass estimates provided by research surveys and because of the recruitment of a relatively strong 1970 year class. To respond to these concerns and to provide an updated biomass estimate with better precision than for previous estimates, a trawl survey was conducted between 22 March and 2 May 1979. The survey was designed and conducted jointly by the Northwest and Alaska Fisheries Center of the National Marine Fisheries Service, the Washington Department of Fisheries, and the Oregon Department of Fish and Wildlife with the primary objective of obtaining information needed for improved management of this species. The objective was attained through stratification of th...

Reasoning about actions necessarily involves tracking the truth of assertions about the world over time. The SIPE planning system retains the efficiency of the STRIPS assumption for this while enhancing expressive power by allowing the specification of a causl theory. Separation of knowledge about causality from knowledge about actions relieves operators of much of their representational burden and allows them to be applicable in a wide range of contexts. The implementation of causal theories is described, together with examples and evaluations of the system's expressive power and efficiency. Le raisonnement au sujet d'actions implique necessairement la verite des assertions a propos du monde sur le temps. Le systeme de planification SIPE conserve l'efficacite de l'hypothese STRIPS tout en augmentant le pouvoir expressif par le biais de la specification d'une theorie causale. La separation des connaissances relatives a la causalite des connaissances relatives aux actions soulage les operateurs d'une bonne partie de leur fardeau de representation et rend ceux-ci applicables dans une plus grande variete de contextes. La mise en oeuvre des theories causales est decrite et des exemples ainsi que des evaluations de la puissance et de l'efficacite du systeme sont fournis.

In line with Dabrowki's theory of Positive Disintegration, deGrace recently reported no significant difference in terms of anxiety level between groups of actualized and nonactualized Ss. Several methodological and theoretical flaws noted in the deGrace study led the present authors to hypothesize that actualized Ss would score significantly lower than nonactualized Ss on separate but conceptually related measures of manifest or neurotic anxiety. Ss (83 females and 42 males) were administered the Personal Orientation Inventory, the IPAT Anxiety Scale, and the Taylor Manifest Anxiety Scale. The results, which substantiate the hypothesis that levels of actualization and anxiety are correlated negatively, are discussed in relation to the conceptual distinction between debilitating and facilitating anxiety and their respective effects on psychological growth.

The gel pond concept is a unique modification of the conventional salt gradient solar pond. It replaces the salinity gradient zone by a transparent polymer gel and thereby eliminates all problems of instability associated with the former. A framework for the preliminary design of a gel pond to serve different purposes has been presented here. Heat extraction at constant pond storage zone temperatures of 40°–80°C at storage zone depths of 2–5 m has been considered and optimum pond dimensions have been predicted depending upon maximum and minimum heat load constraints. The computer simulations are carried out with the meteorological conditions for Albuquerque, New Mexico. For example, the simulations show that the gel pond can provide an average heat load of 107 W/m2, a typical domestic water heating requirement, at a constant pond temperature of 40°C with a storage zone depth of 4.0 m and gel thickness of 0.6 m. For the case of power generation, the pond can provide a minimum of 32 W/m2 at a constant pond temperature of 80°C with a storage zone depth of 4 m and gel thickness of 0.6 m. These factors combined with the easy operation and maintenance of the gel pond seem to make it a better alternative compared with the conventional salt gradient pond. Le concept de bassin avec gel constitue une modification originale de l'etang de saumure conventionnel avec gradient, pour le stockage de l'energie solaire. La zone du gradient de salinite est remplaces par un gel de polymere transparent, ce qui permet d'eliminer l'ensemble des problemes d'instabilite relies au concept conventionnel. Dans ce travail, on propose une methode pour la conception preliminaire d'un bassin avec gel utilisable pour repondre a une variete de problemes. On a pris en consideration l'extraction de chaleur a des temperatures de la zone de stockage en bassin constantes et comprises entre 40 et 80°C et pour des profondeurs de 2 a 5 m, et on a predit les dimensions optimales du bassin en fonction de contraintes de charge thermique minimale et maximale. Les simulations par ordinateur sont effectuees avec les conditions meteorologiques d'Albuquerque, au Nouveau-Mexique. Par exemple, les simulations montrent que le bassin avec gel peut fournir une charge thermique moyenne de 107 W/m2, une valeur typique pour le chauffage de l'eau domestique, a une temperature constante de bassin de 40°C, avec une profondeur de la zone de stockage de 4 m et une epaisseur de bel de 0,6 m. En ce qui concerne la generation d'electricite, le bassin peut fournir un minimum de 32 W/m2 a une temperature de bassin constante de 80°C, avec une profondeur de la zone de stockage de 4 m et une epaisseur de gel de 0,6 m. Ces facteurs, combines a un entretien et un fonctionnement faciles du bassin a gel semble constituer un meilleur choix comparativement au bassin a gradient de sel conventionnel.

In real-world domains (e.g., a mobile robot environment), things do not always proceed as planned, so it is important to develop better execution-monitoring techniques and replanning capabilities. This paper describes these capabilities in the SIPE (System for Interactive Planning and Execution Monitoring) planning system. The motivation behind SIPE is to place enough limitations on the representation so that planning can be done efficiently, while retaining sufficient power to still be useful. This work assumes that new information given to the execution monitor is in the form of predicates, thus avoiding the difficult problem of how to generate these predicates from information provided by sensors. The replanning module presented here takes advantage of the rich structure of SIPE plans and is intimately connected with the planner, which can be called as a subroutine. This allows the use of SIPE's capabilities to determine efficiently how unexpected events affect the plan being executed and, in many cases, to retain most of the original plan by making changes in it to avoid problems caused by these unexpected events. SIPE is also capable of shortening the original plan when serendipitous events occur. A general set of replanning actions is presented along with a general replanning capability that has been implemented by using these actions. Dans les contextes de type monde-reel (e.g., un environnement de robot mobile), les choses n'arrivent pas toujours comme prevues, aussi, il est important de developper de meilleures techniques de controle de ľexecution et des possibilityes de relancer la generation de plan. Cet article decrit ces possibilityes dans le systeme de generation de plan SIPE (systeme pour la generation de plan interactive et le controle de ľexecution). La motivation qui sous-tend SIPE est ?apporter assez de limitations sur la representation pour que la generation de plan se fasse efficacement, tout en preservant suffisamment de puissance pour rester performant. Ce travail suppose que ľinformation nouvelle donnee au controleur ?execution est sous forme predicative; on contourne ainsi le difficile probleme de la generation des predicats a partir de ľinformation fournie par les senseurs. Le module de re-planification presente ici exploite la richesse structural des plans de SIPE et est etroitement relie au generateurde plan, qui peut ětre defini comme un sous-programme. Ceci permet ?utiliser les capacityes de SIPE pour determiner efficacement comment des evenements imprevus ont une incidence sur le plan en cours ?execution et, dans de nombreux cas, de conserver une part importantc du plan original en y apportant des modifications pour contourner les problemes poses par ces evenements imprevus. SIPE est aussi capable de raccourcir le plan original lorsque des evenements inattendus le permettent. Un ensemble general ?actions de re-planification est decrit avec un precede general de re-planification qui a ete execute en utilisant ces actions.

Deep plowing reduced uptake of Sr85 by four irrigated crops on Pullman silty clay loam at Bushland, Texas. Uptake was further reduced when Na2CO3 was plowed under with the Sr85. The relative concentrations of Sr85 in mature soybean (Glycine max), sugar beet (Beta vulgaris), sudangrass (Sorghum sudanense), and cabbage (Brassica oleracea var capitata) plants grown with Sr85 applied in different treatments were: rotary tilled 20 cm deep, 100; plowed 90 cm deep, 25–50; plowed 90 cm deep with 22,400 kg/ha (10 tons/acre) of Na2CO3, 3–7. In the plowing treatments, 90% of both the Sr>85 and the Na2CO3 were banded in the furrow deeper than 75 cm. Crop yields were increased by deep plowing and were affected very little by the application of Na2CO3. This experiment demonstrates that a toxic chemical can be plowed under deeply with radioactive contamination to reduce the uptake of the radioactive material with little effect on yield from the chemical.

In a recent article, Wilkins, Hjelle, and Thompson (1977) argued that unlike the Dabrowski-deGrace hypothesis, self-actualized Ss should have lower levels of manifest anxiety than low self-actualized Ss. Wilkins et al. demonstrated that this was indeed a preferable hypothesis. The present experiment concerns the relationship of actualization to state and trait anxiety. Ss were administered the Personal Orientation Inventory, the Taylor Manifest Anxiety Scale, and Catteil's measure of state-trait anxiety. The results support the Wilkins et al. reformulation by demonstrating that: (1) high self-actualized Ss had lower trait anxiety scores; and (2) high self-actualized Ss were susceptible to state anxiety within the limits established by their trait anxiety level.

Nursing home patients were studied to determine the usefulness of a maintenance dose of digoxin in elderly patients with normal sinus rhythm. Of 64 patients, 26 were identified to be on digoxin. Thorough history and physical examination were done on all the patients. Baseline electrocardiogram showed normal sinus rhythm in 19 patients, who were observed very closely for the period of four months after withdrawal of digoxin. Eighteen of 19 patients did well without digoxin, which suggests that most of the elderly nursing home patients with normal sinus rhythm do not need a maintenance dose of digoxin. J Am Geriatr Soc 33:850, 1985