2,232 research outputs found
The dynamic consequences of invasion: negative plant-soil feedbacks on natives increase ver the time course of invasion
*a) Background/Questions/Methods*
Exotic species can negatively impact native community members, directly through interference competition, or indirectly by altering interactions between native species and other species such as pathogens and mutualists. Soil microbial communities have been shown to respond to invasive species, yet are relatively stable and may take time to respond to perturbations. For this reason, microbe-mediated effects of invasives on natives may take time to develop and may change throughout the invasion process. Few studies have investigated how species interactions between natives and exotics change during invasions.

_Acer platanoides_ was introduced into the US from Europe in 1756 and has since invaded intact forests, lowering understory diversity and inhibiting native tree species regeneration. We hypothesize that _A. platanoides_ invasion will decrease seedling survival in the native _A. saccharum_ by changing the soil microbial community through plant-soil feedbacks (PSF), and this relationship will intensify over the course of an invasion. We collected soil samples from beneath the canopies of both species co-occurring in Michigan forests that had been invaded by _A. platanoides_ for varying time periods. In the greenhouse, we inoculated seedlings of both species with the microbial communities to determine how the soil community affects seedling survival and growth.

*b) Results/Conclusion*
The microbe-mediated negative effects of _A. platanoides_ on survival of the native congener _A. saccharum_ increased with increasing invasion age (negative correlation between invasion age and _A. saccharum_ survival; r = -0.806, R^2^ = 0.65, p = 0.032). This result was not related to _A. platanoides_ density, suggesting that age of invasion drives this pattern. Contrastingly, invasion age did not significantly influence survival of _A. platanoides_ seedlings, indicating that _A. platanoides’_ PSF impacts native species but not on conspecific regeneration. Overall, _A. platanoides_ seedlings had increased growth (more and larger leaves) when grown in soil communities collected from the native _A. saccharum_, but _A. saccharum_ seedlings had reduced growth when grown in conspecific soil (p = 0.044). These results suggest that invasive species may have increased performance in exotic ranges by their ability to modify the soil microbial community in a manner that suppresses the growth of native species.

We show the microbial community cultivated by an invader alters the performance of a native plant species, and this effect increases over the course of an invasion. In future work, we plan to identify changes in microbial community composition and the relative abundances of mutualists versus antagonists in response to invasion to identify potential mechanisms
A Case Report of Case Report Pursuit by Medical Student
Medical students often seek case reports as vehicles for academic writing opportunities, conference presentation avenues, and residency/fellowship application highlights. Here we review a case where, due to unfortunate circumstances, a student made a unique diagnosis central to proper patient clinical care, wished to write up the case subsequently, but was ultimately excluded from the final work stemming from the patient case. We review the pitfalls that occurred in the process of pursuing publication of an interesting case, the educational value of pursuing case reports for students, the necessity for strong mentorship in this process, and general principles that medical students can follow regarding case report creation to avoid being burned
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Targeting STAT3 in Cancer with Nucleotide Therapeutics.
Signal transducer and activator of transcription 3 (STAT3) plays a critical role in promoting the proliferation and survival of tumor cells. As a ubiquitously-expressed transcription factor, STAT3 has commonly been considered an "undruggable" target for therapy; thus, much research has focused on targeting upstream pathways to reduce the expression or phosphorylation/activation of STAT3 in tumor cells. Recently, however, novel approaches have been developed to directly inhibit STAT3 in human cancers, in the hope of reducing the survival and proliferation of tumor cells. Several of these agents are nucleic acid-based, including the antisense molecule AZD9150, CpG-coupled STAT3 siRNA, G-quartet oligodeoxynucleotides (GQ-ODNs), and STAT3 decoys. While the AZD9150 and CpG-STAT3 siRNA interfere with STAT3 expression, STAT3 decoys and GQ-ODNs target constitutively activated STAT3 and modulate its ability to bind to target genes. Both STAT3 decoy and AZD9150 have advanced to clinical testing in humans. Here we will review the current understanding of the structures, mechanisms, and potential clinical utilities of the nucleic acid-based STAT3 inhibitors
Bending the Curve: Options for Achieving Savings and Improving Value in Health Spending
Analyzes the potential of fifteen federal health policy options to lower spending over the next ten years and yield higher value on investments in health care
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The relationship between kinship support services and placement outcomes
This study examined the relationship between kinship support services and placement outcomes using secondary data collected by Chang and Liles (2004) in the Counties of San Bernardino and Riverside. This study aimed at assessing kinship care placement outcomes by reviewing the characteristics of kin caregivers and their dependent children, types of financial support and services received, and contact with social workers. This study sample included 130 kinship caregivers and 291 dependent children from the original study (Chang & Liles, 2007)
Cognitive bias modification training in adolescents: persistence of training effects
Negative biases in the interpretation of social information are associated with anxious symptoms in adolescents. Previous studies have attempted to modify interpretive biases to alleviate anxious mood responses but the longevity of such training effects has not been established. A cognitive bias modification of interpretations (CBM-I) paradigm was administered to sixty-nine 15–17 year-olds. Participants were either trained to interpret ambiguous social situations positively, or received control training that contained no emotional content. Participants showed significantly weaker endorsement of negative interpretations of novel ambiguous information following positive training than following control. Positive CBM-I training effects on interpretation did not differ between a group tested immediately following training and one tested 24 h later. Results provided no evidence of differential changes in state anxiety as a direct result of CBM-I training. The persistence of training effects of suppressing negative biases for ambiguous social information is encouraging for future work that might use bias-training methods in adolescents as buffers against negative emotional responses
The Freedom to Choose: Factors Shaping Women’s Parenthood Decisions
This report investigates the multifaceted factors that influence North American women’s decisions in whether to pursue motherhood, and how society might empower women with the true freedom to decide based on personal desires and life goals rather than external factors that are often perceived or experienced as uncontrollable. Drawing upon one-on-one interviews, polls, and existing literature, the study explores how themes such as interpersonal relationships, financial stability, policy support, and the loss of personal and leisure time associated with having children impact decision-making. We will then delve into strategies aimed at mitigating external barriers that influence women's decision-making regarding having children. By addressing these barriers, my hope is to ensure that women’s decisions on whether to pursue parenthood is driven by personal yearning and reflection rather than external restrictions or influences
Hearing function in children with chronic renal dysfunction.
The primary aim of the research was to describe hearing function in a group of children with chronic renal dysfunction receiving treatment in an academic hospital in Johannesburg, South Africa. Specific objectives in the study were to determine the prevalence of hearing loss in paediatric patients with chronic renal dysfunction; to describe the type, degree and configuration of the hearing loss; and to establish if there was a relationship between the presenting hearing loss and the severity of renal dysfunction, the different treatment regimens, duration of renal dysfunction, and the duration of treatment.
One hundred children between the ages five -18 years participated in the study and comprised 65 males and 35 females. The mean age of the participants was 11.68 years.
A cross-sectional, descriptive, quantitative research design was employed. All participants underwent a case history interview and a full audiological examination which included an otoscopic examination, immittance testing (tympanometry and ipsilateral acoustic reflex testing), pure tone audiometry including extended high frequency testing up to 16 kilohertz as well as diagnostic distortion product otoacoustic emission testing. A record review was also done.
Both descriptive and inferential statistics were used to analyse the collected data. Inferential statistics included parametric measures using multiple regression measures as well as non parametric measures using the Kruskal-Wallis statistical analysis.
Results revealed that there was a high prevalence of hearing loss in children with chronic renal dysfunction. Results from the extended high frequency pure tone testing as well as the diagnostic distortion product testing revealed that the most common hearing loss was a low and high to ultrahigh frequency mild sensorineural hearing loss. The study showed that there was no relationship between the severity of hearing loss and the severity of renal dysfunction, or the duration of renal dysfunction and the duration of treatment. However, the study showed that there was a relationship between the severity of hearing loss and certain treatments, that is,
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haemodialysis and the use of ototoxic medication such as loop diuretics, tuberculosis medication, and antimalarial medication.
As the potential to miss hearing loss in this population is high, the research highlighted the importance of extended high frequency audiometry as well as diagnostic distortion product otoacoustic emission testing for the use of ototoxic monitoring in patients with chronic renal dysfunction. The research also highlighted the need for further research in this area as well as the need for educating medical personnel and caregivers working with children with chronic renal disease
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