Crop Performance and Yield of Groundnut, Sesame and Roselle in an Agroforesty Cropping System with Acacia senegal in North Kordofan (Sudan)

Crop performance and yield of groundnut (Arachis hypogea), sesame (Sesamum indicum) and roselle (Hibiscus sabdariffa) were investigated in an intercropping system with Acacia senegal and compared with sole cropping. The study was conducted in North Kordofan (Sudan) on loamy sand. Experimental design was a randomized complete block with split plots.Crop performance and crop yield of groundnut, sesame and roselle were significantly (p 0.05) reduced in the intercropping system compared to sole cropping. However, yield reduction in groundnut (53%) was much higher than in sesame (6%) and roselle (14%). The reduction in yield of the intercropping plots could be due to the high tree density, which results in water and light competition between the trees and the agricultural crops

Water and nitrogen uptake patterns following moisture pulses in a cold desert community

Journal ArticleVariation in the ability to utilize pulses of both water and nitrogen (N) is one possible mechanism allowing the coexistence of species in the cold desert community on the Colorado Plateau. We simulated 25-mm precipitation events and used stable isotope tracers (2H and 15N) to follow water and N uptake patterns in six dominant perennials (Artemisia filifolia, Coleogyne ramosissima, Cryptantha flava, Ephedra viridis, Quercus havardii, and Vanclevea stylosa) at different times of the growing season

Interspecific competition and resource pulse utilization in a cold desert community

Journal ArticleIn desert ecosystems a large proportion of water and nitrogen is supplied in rain-induced pulses. It has been suggested that competitive interactions among desert plants would be most intense during these pulse periods of high resource availability. We tested this hypothesis with three cold desert shrub species of the Colorado Plateau (Gutierrezia sarothrae, Atriplex confertifolia, and Chrysothamnus nauseosus), which differ in their distribution of functional roots. In a three-year field study we conducted a neighbor removal experiment in conjunction with simulated 25-mm precipitation events and the addition of a nitrogen pulse in either spring or summer

Big Five personality and religiosity: Bidirectional cross-lagged effects and their moderation by culture

Objective: Personality has long been assumed to be a cause of religiosity, not a consequence. Yet, recent research suggests that religiosity may well cause personality change. Consequently, longitudinal research is required that examines the bi-directionality between personality and religiosity. The required research must also attend to cultural religiosity - a critical moderator in previous cross-sectional research. Method: We conducted four-wave, cross-lagged panel models assessing the bi-directional effects between religiosity (measured as religious attendance) and the Big Five personality traits over 12 years in 14 samples (Ntotal = 44,485). Each sample used population-representative data from a different German federal state - states that vary widely in religiosity. Results: The findings were the following: (1) Agreeableness, openness, and conscientiousness were associated with changes in religiosity, with the latter two effects being culture-contingent. (2) Religiosity was associated with changes in agreeableness and openness, with the latter effect being culture-contingent. (3) The cross-lagged effects of personality on religiosity were overall stronger than the reverse effects. Conclusions: The directionality between the Big Five and religiosity seems to go both ways and culture matters for those effects. We discuss the power of religiosity to alter personality and the role of culture for this effect and for personality change more generally

Fungal association and root morphology shift stepwise during ontogenesis of orchid Cremastra appendiculata towards autotrophic nutrition

The chlorophyllous, terrestrial orchid Cremastra appendiculata from East Asia is unique concerning its fungal mycorrhiza partners. The initially mycoheterotrophic protocorms exploit rather specialized non-rhizoctonia saprotrophic Psathyrellaceae. Adult individuals of this orchid species are either linked to Psathyrellaceae being partially mycoheterotrophic or form mycorrhiza with fungi of the ubiquitous saprotrophic rhizoctonia group. This study provides new insights on nutrition mode, subterranean morphology and fungal partners across different life stages of C. appendiculata. We compared different development stages of C. appendiculata to surrounding autotrophic reference plants based on multi-element natural abundance stable isotope analyses (δ(13)C, δ(15)N, δ(2)H, δ(18)O) and total N concentrations. Site- and sampling-time-independent enrichment factors of stable isotopes were used to reveal trophic strategies. We determined mycorrhizal fungi of C. appendiculata protocorm, seedling and adult samples using high-throughput DNA sequencing. We identified saprotrophic non-rhizoctonia Psathyrellaceae as dominant mycorrhizal fungi in protocorm and seedling rhizomes. In contrast, the roots of seedlings and mature C. appendiculata were mainly colonized with fungi belonging to the polyphyletic assembly of rhizoctonia (Ceratobasidium, Thanatephorus and Serendipitaceae). Mature C. appendiculata did not differ in isotopic signature from autotrophic reference plants suggesting a fully autotrophic nutrition mode. Characteristic of orchid specimens entirely relying on fungal nutrition, C. appendiculata protocorms were enriched in (15)N, (13)C and (2)H compared to reference plants. Seedlings showed an intermediate isotopic signature, underpinning the differences in the fungal community depending on their subterranean morphology. In contrast to the suggestion that C. appendiculata is a partially mycoheterotrophic orchid species, we provide novel evidence that mature C. appendiculata with rhizoctonia mycobionts can be entirely autotrophic. Besides an environmentally driven variability among populations, we suggest high within-individual flexibility in nutrition and mycobionts of C. appendiculata, which is subject to the ontogenetic development stage

A new and efficient approach to time-dependent density-functional perturbation theory for optical spectroscopy

Using a super-operator formulation of linearized time-dependent density-functional theory, the dynamical polarizability of a system of interacting electrons is given a matrix continued-fraction representation whose coefficients can be obtained from the non-symmetric block-Lanczos method. The resulting algorithm allows for the calculation of the {\em full spectrum} of a system with a computational workload which is only a few times larger than that needed for {\em static} polarizabilities within time-independent density-functional perturbation theory. The method is demonstrated with the calculation of the spectrum of benzene, and prospects for its application to the large-scale calculation of optical spectra are discussed.Comment: 4 pages, 2 figure

The population of deformed bands in 48^{48}Cr by emission of 8^{8}Be from the 32^{32}S + 24^{24}Mg reaction

Using particle-$\gamma$ coincidences we have studied the population of final states after the emission of 2 $\alpha$-particles and of $^{8}$Be in nuclei formed in $^{32}$S+$^{24}$Mg reactions at an energy of $\textrm{E}_{\rm L}(^{32}\textrm{S}) = 130 {\rm MeV}$. The data were obtained in a setup consisting of the GASP $\gamma$-ray detection array and the multidetector array ISIS. Particle identification is obtained from the $\Delta$E and E signals of the ISIS silicon detector telescopes, the $^{8}$Be being identified by the instantaneous pile up of the $\Delta$E and E pulses. $\gamma$-ray decays of the $^{48}$Cr nucleus are identified with coincidences set on 2 $\alpha$-particles and on $^{8}$Be. Some transitions of the side-band with $K^\pi=4^{-}$ show stronger population for $^{8}$Be emission relative to that of 2 $\alpha$-particles (by a factor $1.5-1.8$). This observation is interpreted as due to an enhanced emission of $^{8}$Be into a more deformed nucleus. Calculations based on the extended Hauser-Feshbach compound decay formalism confirm this observation quantitatively.Comment: 17 pages, 9 figures accepted for publication in J. Phys.

Relationship between self-esteem and psychological health

This thesis examines the relationship between self-esteem and psychological health. In Chapter 1, I define self-esteem and psychological health, illustrate the prominence of these two psychological constructs, and review the literature on the relation between self-esteem and psychological health. As we will see, self-esteem can be defined as one's overall evaluation as a person, and psychological health can be defined as the absence of depression, anxiety, and negative affect together with the presence of life satisfaction and positive affect. Further, we will see that self-esteem and psychological health are among the most frequently researched psychological constructs. Thus, the corpus of research on the relationship between self-esteem and psychological health is massive. Nonetheless, the nature and dynamics of this relationship are complex and far from being fully understood. The empirical research presented in this thesis helps to better understand this relationship. To this end, I have conducted three empirical lines of research. The three lines of research approach the same overarching goal from three very different angles. In the first empirical chapter (Chapter 2), I report a line of research in which my collaborators and I studied the impact of one facet of psychological health - i.e., chronic mood - on self-esteem when recalling positive and negative past selves. In four studies, we found that chronically happy people assimilated towards a recalled positive self and contrasted away from a recalled negative self, which in both cases lead to a relative increase in self-esteem. Chronically sad people, on the other hand, assimilated towards a recalled negative self and contrasted away from a recalled positive self, which in both cases lead to a relative decrease in self-esteem. Thus, this research shows that psychological health in the form of chronic mood can impact self-esteem via the medium of recalling past selves. The research reported in the second empirical chapter (Chapter 3) was motivated by the conviction that a full understanding of the relationship between self-esteem and psychological health can be obtained only by placing this relationship in a larger context involving other psychological variables. Past research suggests that belongingness is the one psychological construct that is particularly relevant in this respect. Thus, Chapter 3 reports a line of research studying the relations between belongingness, self-esteem, and psychological health. In three studies, we developed and validated a novel two-dimensional measure of people's perceptions of the belongingness they experience from other people. The measure assesses the amount of belongingness experienced and the degree to which people perceive this belongingness as being unconditional or conditional on their achievements and contributions. We extended past social psychological research by demonstrating that the unconditionally of belongingness explains variance in psychological health independent of the amount of belongingness. More importantly, the data showed that self-esteem plays a central role in these relationships. Specifically, the amount of self-esteem (e.g., global self-esteem) mediated the relationship between the amount of belongingness and psychological health, whereas the conditionally of self-esteem (i.e., global contingent self-esteem) mediates the relationship between the unconditionally of belongingness and psychological health. In the final empirical chapter (Chapter 4), we wanted to elucidate why past empirical research failed to find a relationship between implicit measures of self-esteem and self-reported psychological health when controlling for explicit measures of self-esteem. One reason for this puzzling but consistent null result may be that existent implicit measures of self-esteem assess domain-specific self-esteem, but not global self-esteem. Thus, Chapter 4 reports a line of research studying the relation between psychological health and a novel implicit measure of global self-esteem. Six studies developed and validated this new implicit measure, finding that our newly developed measure predicts higher psychological health even when controlling for explicitly measured self-esteem. Finally, Chapter 5 reviews the contribution of the research presented in this thesis to our understanding of the relationship between self-esteem and psychological health. Overall, the research emphasises the complexity of the multi-faceted processes that underlie this relationship. Directions for future research are discussed.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Religious people only live longer in religious cultural contexts: A gravestone analysis.

Religious people live longer than non-religious people according to a staple of social science research. Yet, are those longevity benefits an inherent feature of religiosity? To find out, we coded gravestone inscriptions and imagery in order to assess the religiosity and longevity of 6,400 deceased people from religious and non-religious U.S. counties. We show that in religious cultural contexts, religious people lived 2.2 years longer than did non-religious people. In non-religious cultural contexts, however, religiosity conferred no such longevity benefits. Evidently, a longer life is not an inherent feature of religiosity. Instead, religious people only live longer in religious cultural contexts where religiosity is valued. Our study answers a fundamental question on the nature of religiosity and showcases the scientific potential of gravestone analyses

The role of a circumferential septal fiberotomy (CSF) in enhancing orthodontic stability- a randomized controlled clinical trial

Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenInngangur: Mælt hefur verið með að gera fiberotomiu eftir tannréttingameðferð til að auka stöðugleika. Sú kenning var prófuð í þessari rannsókn. Efni og aðferðir: Níu einstaklingar sem voru að ljúka tannréttingameðferð voru valdir til að taka þátt. Neðri boginn var fjarlægður úr sporum, fiberotomia var framkvæmd í annarri hlið frá augntönn til miðframtannar en hin hliðin þjónaði hlutverki viðmiðunarhóps. Í byrjun og á 4 vikna fresti í allt að 6 mánuði voru tekin mát og ljósmyndir. Irregularity Index Little var notaður til að mæla þrengsli á módelum, en ljósmyndir af módelum voru skannaðar inn og tölvuforrit greindi allar breytingar sem urðu á tönnum á tímabilinu. Hliðrunarhreyfingar sem og snúningshreyfingar sem og breytingar á tannholdsindexum voru skráðar. Hvorug mælingaraðferðin sýndi marktækan mun á stöðugleika í þeirri hlið sem var skorin miðað við viðmiðunarhóp. Tannhold skaðaðist ekki við fiberotomiuna. Niðurstöður: Þar sem fiberotomia virðist ekki auka stöðugleika tanna eftir tannréttingameðferð, er ekki hægt að mæla með aðferðinni.Introduction: Circumferential septal fiberotomy (CSF) following orthodontic treatment has been propagated to improve stability and prevent relapse of tooth alignment. The hypothesis of no difference of performed CSF and controls was tested. Material and Methods: In 9 consecutively admitted patients at the end of orthodontic tooth alignment the lower archwire was removed. CSF was performed from canine to the central incisor on a randomly chosen side, while the contralateral side served as unsurgerized control. At baseline and every 4 weeks up to 6 months, study casts were taken and 1) analyzed using the Irregularity Index of Little and 2) photographed, traced and superimposed digitally. The translational and rotational movements of teeth as well as gingival parameters were analyzed as well. By using the II and by superimposing the tracings, no statistically significant differences were found between test (CSF) and control sides for any parameters. Moreover, CSF did not impinge on the gingival tissues. Conclusion: Since CSF did not improve stability of orthodontically aligned teeth nor prevent relapse during the healing phase of up to 6 months, CSF should not be recommended following orthodontic therapy. Key words: Fiberotomy, orthodontic treatment, stability, rotational relapse, gingival recession