University of Nebraska–Lincoln

About: University of Nebraska–Lincoln is a education organization based out in Lincoln, Nebraska, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 28059 authors who have published 61544 publications receiving 2139104 citations. The organization is also known as: Nebraska & UNL.

Exploiting genetic diversity from landraces in wheat breeding for adaptation to climate change

Abstract: Climate change has generated unpredictability in the timing and amount of rain, as well as extreme heat and cold spells that have affected grain yields worldwide and threaten food security. Sources of specific adaptation related to drought and heat, as well as associated breeding of genetic traits, will contribute to maintaining grain yields in dry and warm years. Increased crop photosynthesis and biomass have been achieved particularly through disease resistance and healthy leaves. Similarly, sources of drought and heat adaptation through extended photosynthesis and increased biomass would also greatly benefit crop improvement. Wheat landraces have been cultivated for thousands of years under the most extreme environmental conditions. They have also been cultivated in lower input farming systems for which adaptation traits, particularly those that increase the duration of photosynthesis, have been conserved. Landraces are a valuable source of genetic diversity and specific adaptation to local environmental conditions according to their place of origin. Evidence supports the hypothesis that landraces can provide sources of increased biomass and thousand kernel weight, both important traits for adaptation to tolerate drought and heat. Evaluation of wheat landraces stored in gene banks with highly beneficial untapped diversity and sources of stress adaptation, once characterized, should also be used for wheat improvement. Unified development of databases and promotion of data sharing among physiologists, pathologists, wheat quality scientists, national programmes, and breeders will greatly benefit wheat improvement for adaptation to climate change worldwide.

The New Homelessness Revisited

Abstract: The new homelessness has drawn sustained attention from scholars over the past three decades. Definitional inconsistencies and data limitations rendered early work during this period largely speculative in nature. Thanks to conceptual, theoretical, and methodological progress, however, the research literature now provides a fuller understanding of homelessness. Contributions by sociologists and other social scientists since the mid-1990s differentiate among types of homelessness, provide credible demographic estimates, and show how being homeless affects a person’s life chances and coping strategies. Agreement also exists about the main macro- and micro-level causes of homelessness. Active lines of inquiry examine public, media, and governmental responses to the problem as well as homeless people’s efforts to mobilize on their own behalf. Despite the obstacles faced when studying a stigmatized population marked by high turnover and weak anchors to place, recent investigations have significantly influenced homelessness policy. A greater emphasis on prevention should further strengthen the research-policy nexus.

The tripartite nature of marital commitment: Personal, moral, and structural reasons to stay married.

Abstract: This study assesses the empirical viabilihy of Johnson's (1991) commitment framework. The core principle is that commitment, rather than a unitary phenomenon, involves three distinct experiences: wanting to stay married, feeling morally obligated to stay married, and feeling constrained to stay married. Using data from a sample of married couples, we show that direct measures of the three experiences are not highly correlated with each other, that a measure of so-called global commitment is a function primarily, if not exclusively; of personal commitment, that the three direct measures of the experiences of commitment are associated for the most part with the components of each type as hypothesized in the commitment framework, and that the three types of commitment and their components are not associated in the same way with other variables. Key Words: commitment, marriage, stability. What does it mean to be committed to a relationship? Johnson (1973, 1982, 1991, in press) has argued that the experience of commitment is not unitary, that there are three distinct types of commitment, each with a different set of causes, a different phenomenology, and different cognitive, emotional, and behavioral consequences. Personal commitment refers to the sense of wanting to stay in the relationship, moral commitment to feeling morally obligated to stay, and structural commitment to feeling constrained to stay regardless of the level of personal or moral commitment. We report an investigation of the experiential nature of commitment in the context of first marriages that have survived from 1981 to 1994. Data are presented on the relationships among the three types of commitment and on the relationship of each of the three types to so-called global commitment. We also show that the three types of commitment are functions of different components of commitment and are related differently to a number of other antecedents and consequences. TYPES OF COMMITMENT Johnson's (1991) commitment framework is organized around a discussion of the components of three major types of commitment and identifies the key sets of factors that contribute to the experiences of personal, moral, or structural commitment to a particular relationship. The first two types of commitment, personal and moral, are experienced as internal to the individual and are a function of the person's own attitudes and values. The third type of commitment, structural, is experienced as external to the individual and is a function of perceptions of constraints that make it costly for the individual to leave the relationship. Personal Commitment Personal commitment. the extent to which one wants to stay in a relationship, is affected by three components (Johnson, 1991). First, individuals may want to continue a relationship because they are attracted to their partner. Second, personal commitment is a function of attraction to the relationship. Although under many conditions these two components of personal commitment are correlated with each other, they clearly are not the same phenomenon. One can feel a strong attraction to an individual who, in the context of the relationship, behaves in ways that one finds quite unsatisfactory. Furthermore, the attractiveness of a relationship may be experienced as a joint function of the actions of both partners or may be attributed primarily to oneself. For example, one way a physically abusive husband controls his wife is by convincing her that the abuse is more her fault than his (Johnson, 1995; Kirkwood, 1993; Pence & Paymar, 1993). In such a case, a woman may have quite negative feelings about the violent relationship but still experience strong feelings of love for her partner, who has convinced her that he is not the problem. The third component of personal commitment is couple identity. Social relationships are a central part of identity (Kuhn & McPartland, 1954; McCall & Simmons, 1978). …

Fungi in the healthy human gastrointestinal tract.

Abstract: Many species of fungi have been detected in the healthy human gut; however, nearly half of all taxa reported have only been found in one sample or one study. Fungi capable of growing in and colonizing the gut are limited to a small number of species, mostly Candida yeasts and yeasts in the family Dipodascaceae (Galactomyces, Geotrichum, Saprochaete). Malassezia and the filamentous fungus Cladosporium are potential colonizers; more work is needed to clarify their role. Other commonly-detected fungi come from the diet or environment but either cannot or do not colonize (Penicillium and Debaryomyces species, which are common on fermented foods but cannot grow at human body temperature), while still others have dietary or environmental sources (Saccharomyces cerevisiae, a fermentation agent and sometime probiotic; Aspergillus species, ubiquitous molds) yet are likely to impact gut ecology. The gut mycobiome appears less stable than the bacterial microbiome, and is likely subject to environmental factors.