The estimated prevalence of iron deficiency in the world suggests that there should be widespread negative consequences of this nutrient deficiency in both developed and developing countries. In ...considering the reality of these estimates, the Belmont Conference seeks to reconsider the accepted relationships of iron status to physiological, biochemical and neurological outcomes. This review focuses on the biological processes that we believe are the basis for alterations in the immune system, neural systems, and energy metabolism and exercise. The strength of evidence is considered in each of the domains and the large gaps in knowledge of basic biology or iron-dependent processes are identified. Iron is both an essential nutrient and a potential toxicant to cells; it requires a highly sophisticated and complex set of regulatory approaches to meet the demands of cells as well as prevent excess accumulation. It is hoped that this review of the more basic aspects of the biology of iron will set the stage for subsequent in-depth reviews of the relationship of iron to morbidity, mortality and functioning of iron-deficient individuals and populations.
The causal effects among uplift, climate, and continental weathering cannot be fully addressed using presently available geochemical proxies. However, stable potassium (K) isotopes can potentially ...overcome the limitations of existing isotopic proxies. Here we report on a systematic investigation of K isotopes in dissolved load and sediments from major rivers and their tributaries in China, which have drainage basins with varied climate, lithology, and topography. Our results show that during silicate weathering, heavy K isotopes are preferentially partitioned into aqueous solutions. Moreover, δ
41K values of riverine dissolved load vary remarkably and correlate negatively with the chemical weathering intensity of the drainage basin. This correlation allows an estimate of the average K isotope composition of global riverine runoff (δ
41K = −0.22‰), as well as modeling of the global K cycle based on mass balance calculations. Modeling incorporating K isotope mass balance better constrains estimated K fluxes for modern global K cycling, and the results show that the δ
41K value of seawater is sensitive to continental weathering intensity changes. Thus, it is possible to use the δ
41K record of paleo-seawater to infer continental weathering intensity through Earth’s history.
Background
Previous studies indicate that early symptomatic improvement, typically observed during the first 4 weeks of psychological therapy, is associated with positive treatment outcomes for a ...range of mental health problems. However, the replicability, statistical significance, and magnitude of this association remain unclear.
Aim
The current study reviewed the literature on early response to psychological interventions for adults with depression and anxiety symptoms.
Methods
A systematic review and random effects meta‐analysis were conducted, including studies found in Medline, PsychINFO, SCOPUS, Web of Science, and through reference lists and reverse citations.
Results
Twenty‐five eligible studies including 11,091 patients measured early response and examined associations with posttreatment outcomes. It was possible to extract and/or calculate effect size data from 15 studies to conduct a meta‐analysis. A large pooled effect size (g = 0.87 95% confidence interval: 0.63–1.10, p < .0001) indicated that early responders had significantly better posttreatment outcomes compared to cases without early response, and this effect was larger in anxiety (g = 1.37) compared to depression (g = 0.76) measures. Most studies were of good quality and there was no evidence of publication bias. The main limitations concerned insufficient statistical reporting in some studies, which precluded their inclusion in meta‐analysis, and it was not possible to examine effect sizes according to different outcome questionnaires.
Conclusion
There is robust and replicated evidence that early response to therapy is a reliable prognostic indicator for depression and anxiety treatment outcomes.
Banded iron formations (BIFs) record a time of extensive Fe deposition in the Precambrian oceans, but the sources and pathways for metals in BIFs remain controversial. Here, we present Fe- and ...Nd-isotope data that indicate two sources of Fe for the large BIF units deposited 2.5 billion y ago. High-ε Nd and -δ âµâ¶Fe signatures in some BIF samples record a hydrothermal component, but correlated decreases in ε Nd- and δ âµâ¶Fe values reflect contributions from a continental component. The continental Fe source is best explained by Fe mobilization on the continental margin by microbial dissimilatory iron reduction (DIR) and confirms for the first time, to our knowledge, a microbially driven Fe shuttle for the largest BIFs on Earth. Detailed sampling at various scales shows that the proportions of hydrothermal and continental Fe sources were invariant over periods of 10 â°â10 ³ y, indicating that there was no seasonal control, although Fe sources varied on longer timescales of 10 âµâ10 ⶠy, suggesting a control by marine basin circulation. These results show that Fe sources and pathways for BIFs reflect the interplay between abiologic (hydrothermal) and biologic processes, where the latter reflects DIR that operated on a basin-wide scale in the Archean.
Alzheimer’s disease (AD) is a stigmatised condition popularly assumed to be a death sentence for diagnosed individuals. Consequently, people with AD are often deemed incapable (and perhaps unworthy) ...of contributing to the social discourse surrounding their illness experience. Data from qualitative interviews with 18 people diagnosed with the potential precursor of AD known as mild cognitive impairment (MCI) are examined. Using grounded theory methods, analysis revealed overarching themes of uncertainty concerning definitions of memory loss, MCI, and AD as well as distinctions between normal ageing and dementia. While this confusion over the terminology and prognosis mirrors the lack of scientific consensus about nosology and appropriate treatment regimens, such ambiguity creates social and psychological tensions for diagnosed individuals. Arguably, participants’ unequivocal fear of and subsequent desire to differentiate their experiences from Alzheimer’s, however, stems from the exclusively negative social constructions of AD. Drawing from Goffman, these findings demonstrate the psychosocial impact of ‘framing contests’ and how ‘courtesy stigma’ can apply not only to associated persons but also associated conditions, such as MCI to AD. Given the underlying nosological creep – or medicalisation – of the recent diagnostic guidelines proposing two new pre‐dementia stages, understanding the illness narratives of MCI is critical.
The relationship between problematic gaming behavior and self-esteem is well-documented (King & Delfabbro, 2014). Moreover, the basic needs component of Self-Determination Theory has also been ...proposed as an organizing framework to understand gaming motivation (Lafrenière, Verner-Filion, & Vallerand, 2012; Ryan, Rigby, & Przybylski, 2006). Building on these ideas, the current study describes the development of a measure of contingent self-worth (Crocker, Luhtanen, Cooper, & Bouvrette, 2003; Crocker & Wolfe, 2001) specific to gaming experiences within Massively-Multiplayer Online Role Playing Games (MMORPGs), and explores the association between Gaming-Contingent Self-Worth (GCSW) and symptoms of Internet Gaming Disorder (IGD). A sample of MMORPG players was recruited through Amazon's Mechanical Turk (n = 600) to evaluate the reliability and validity of a GCSW scale. Exploratory and confirmatory factor analysis was used to identify a 29-item measure comprised of four components, including validation seeking, reward orientation, competition focus, and detachment. Additional analyses supported the hypothesis that GCSW is a strong predictor of IGD symptoms, beyond the contribution of motivation based on behavioral activities within the game.
•A measure of Gaming-Contingent Self-Worth (GCSW) is developed.•Factors of GCSW include validation seeking, reward orientation, competition focus, and detachment.•Associations between GCSW and Internet Gaming Disorder (IGD) are explored.•GCSW predicts IGD beyond behavioral motives, weekly hours, and global self-esteem.
BACKGROUND:Evidence suggests that brain iron deficiency at any time in life may disrupt metabolic processes and subsequently change cognitive and behavioral functioning. Women of reproductive age are ...among those most vulnerable to iron deficiency and may be at high risk for cognitive alterations due to iron deficiency. OBJECTIVE:We aimed to examine the relation between iron status and cognitive abilities in young women. DESIGN:A blinded, placebo-controlled, stratified intervention study was conducted in women aged 18-35 y of varied iron status who were randomly assigned to receive iron supplements or a placebo. Cognition was assessed by using 8 cognitive performance tasks (from Detterman's Cognitive Abilities Test) at baseline (n = 149) and after 16 wk of treatment (n = 113). RESULTS:At baseline, the iron-sufficient women (n = 42) performed better on cognitive tasks (P = 0.011) and completed them faster (P = 0.038) than did the women with iron deficiency anemia (n = 34). Factors representing performance accuracy and the time needed to complete the tasks by the iron-deficient but nonanemic women (n = 73) were intermediate between the 2 extremes of iron status. After treatment, a significant improvement in serum ferritin was associated with a 5-7-fold improvement in cognitive performance, whereas a significant improvement in hemoglobin was related to improved speed in completing the cognitive tasks. CONCLUSIONS:Iron status is a significant factor in cognitive performance in women of reproductive age. Severity of anemia primarily affects processing speed, and severity of iron deficiency affects accuracy of cognitive function over a broad range of tasks. Thus, the effects of iron deficiency on cognition are not limited to the developing brain.
Despite steadfast interest in the use of arts therapies (ATs) with individuals who have dementia of the Alzheimer's type (DAT), a systematic review of the literature has not been conducted. This ...paper aims to critique this evidence base, including music, visual arts, drama, and dance/movement therapies between the years 1990 and 2010, and make suggestions on how it can be strengthened. The review addresses four questions: (1) What is the focus of the empirical base on using AT with persons who have DAT? (2) (How) have these studies been designed and evaluated? (3) What findings are reported? (4) What does this tell us about the potential of AT for enriching the lives of people with dementia? This analysis reveals that systematically designed, documented, and evaluated AT studies are scarce. Information on research design, operational concepts, measurement tools, and methods of evaluation/analysis are vague, if provided. Disagreement exists about the utilization of theoretical concepts and measurement/evaluation tools. The evidence base is further divided between studies focusing on the ‘product’ versus the ‘process’ of art. Shortcomings in dementia-specific research include a paucity of accounts from participants, failure to extend therapies to individuals in the early stages, a lack of application to those living at home, and often superficial attention to the meaningful aspects of doing art. Models investigating subjective well-being, or ‘enrichment,’ rather than objectively measured biomedical approaches privileging the management of deficits, would expand the evidence base and help ensure that those with dementia receive the services they want, since strictly allopathic methodologies will continue to fall short of adequately evaluating what are deeply idiosyncratic psychosocial issues.
Being diagnosed with Alzheimer's disease marks a status passage formally legitimating the incorporation of forgetfulness into daily life. Based on interviews with diagnosed individuals in California, ...USA, we examine the mechanisms through which an Alzheimer's label is employed to justify forgetfulness, to manage social interactions, and to garner support when deemed necessary, while simultaneously combating the associated
demented “master status.” For diagnosed individuals, the transition from experience to symptom requires a redefinition of everyday forgetfulness into a medical problem. That is, respondents did not routinely perceive their experiences as pathological but rather were socialised into viewing age-related forgetfulness as symbolic of disease. Support groups sponsored by the Alzheimer's Association and memory clinics have a profound impact not only on the formation of group identity, but also on socialising forgetful individuals into diseased identities. The social disenfranchisement accompanying a diagnosis of dementia transforms forgetful older adults into “Alzheimer's patients,” who must manage not only the manifestations of their disease, but also negotiate their interactions and identities. Their adaptation to the “symptoms” of forgetfulness and resultant social relations forms new interactional strategies whereby the diagnosis becomes a resource utilised to get through everyday life. Rather than being passive recipients of a diagnosis, respondents employ the label both as a resource, and as a phenomenon that needs to be incorporated into their self identity.
Results from enriched 57Fe isotope tracer experiments have shown that atom exchange can occur between structural Fe in Fe(III) oxides and aqueous Fe(II) with no formation of secondary minerals or ...change in particle size or shape. Here we derive a mass balance model to quantify the extent of Fe atom exchange between goethite and aqueous Fe(II) that accounts for different Fe pool sizes. We use this model to reinterpret our previous work and to quantify the influence of particle size and pH on extent of goethite exchange with aqueous Fe(II). Consistent with our previous interpretation, substantial exchange of goethite occurred at pH 7.5 (≈ 90%) and we observed little effect of particle size between nanogoethite (average size of 81 × 11 nm; ≈ 110 m2/g) and microgoethite (average size of 590 × 42 nm; ≈ 40 m2/g). Despite ≈90% of the bulk goethite exchanging at pH 7.5, we found no change in mineral phase, average particle size, crystallinity, or reactivity after reaction with aqueous Fe(II). At a lower pH of 5.0, no net sorption of Fe(II) was observed and significantly less exchange occurred accounting for less than the estimated proportion of surface Fe atoms in the particles. Particle size appears to influence the amount of exchange at pH 5.0 and we suggest that aggregation and surface area may play a role. Results from sequential chemical extractions indicate that 57Fe accumulates in extracted Fe(III) goethite components. Isotopic compositions of the extracts indicate that a gradient of 57Fe develops within the goethite with more accumulation of 57Fe occurring in the more easily extracted Fe(III) that may be nearer to the surface.
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