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A Comparison of Environmental Substrate Gradients and Calcium Selectivity in Plant Species of Calcareous Fens in Massachusetts
The distribution and occurrence of plant species within a given region provides insight into the many environmental properties of that region. Although much research has been conducted on plant communities and associated environmental properties, few studies have been conducted on the characteristics of individual plants within those communities. Calcareous fens are wetlands formed by the upwelling of mineral-rich groundwater and often are associated with many unique plant communities and rare species of flora and fauna. Although many studies have documented the vegetation patterns and associated environmental gradients of these fens, none have isolated the specific hydrogeochemical conditions associated with individual species, nor have any studies attempted to document and compare the individual physiological response of species to elevated environmental calcium levels. This research was conducted to estimate environmental calcium requirements for rare as well as common indicator species of calcareous fens of Massachusetts and to examine the relationship between the accumulation of calcium in the tissues of these species to calcium availability in their environment. These factors will be important when determining required conditions for fen restoration and will further the understanding of why these species often only occur in calcareous fens.
Eight calcareous fen study sites at three different locations were established where calciphiles occur in western Massachusetts. In each site, data were collected on the vegetation patterns and associated soil chemistry, water chemistry, and hydrology. In addition, plant tissues were collected and analyzed for calcium. Species distributions were evaluated as to whether they increased in abundance as environmental calcium did or whether they appeared to occur only once a specific calcium threshold was met. In addition, the concentrations of calcium in the tissues were used to determine the extent to which those plants accumulated calcium and how those levels related to levels of calcium in the substrate environment and to their overall distributions.
It was found that certain calciphiles are calcium specialists, i.e. they are more abundant when environmental calcium levels are elevated, absorb greater quantities of calcium and those quantities correlate to the available environmental supply. These species include Parnassia glauca, Packera aurea, Geum rivale and Carex granularis. Of these, Geum rivale and Carex granularis, as well as Carex sterilis, did not occur below calcium concentrations of 48 mg.L-1. However, other calciphiles are calcium generalists, i.e. they are tolerant of elevated calcium levels but show no other relationship with respect to growth or accumulation. These species include Carex flava, Carex hystericina, Juncus nodosus, Solidago patula, Solidago uliginosa, and Symphyotrichum puniceum. In addition, some wetland generalists maintain elevated calcium levels (Symplocarpus foetidus and Mentha arvensis) whereas most others do not (Thelypteris palustris and Fragaria vesca). Of the calciphile and wetland generalist species, some appear to increase in abundance in calcareous fens in relation to increases in accessory benefits (Dasiphora fruticosa and Juncus brachycephalus with pH; Thelypteris palustris and Carex flava with magnesium and possibly Equisetum fluviatile with iron). Combined, these findings characterize the growth habits and calcium accumulation of species that grow in calcareous fens and indicate that calciphiles have varying degrees of dependence on calcium
The vaccine and the virus: An autoethnographic account of HPV, sex education, and the psychosocial effects of STI\u27s
In 2006 the Food and Drug Administration (FDA) approved the Gardasil vaccine to assist in the protection from the Human Papillomavirus (HPV): The leading contributor to cervical cancer. After stressing the importance of the vaccine, but disregarding its inadequacies, young women were subjected to invasive and excessive protocols. This study utilizes autoethnographic methods to understand the psychological and social effects of the individuals who were diagnosed with HPV before the release of the Gardasil 9 vaccine in 2014 and forced to go through these unnecessary procedures before the medical field began adopting imperative changes to treatment
Aspiration Problems for the Indian Rural Poor: Research on Self-Help Groups and Micro-Finance
Our paper explores how poor rural households in India are increasingly accumulating debt through micro-finance initiatives channelled through local self-help groups (SHGs). The aim of micro-finance and SHGs is to provide a cheap source of capital for investment in self-sustaining economic practices — typified by the Velugu programme. However, the reality of micro-finance has been more complicated. It has created a class- and caste-related debt-dependency and vulnerability whilst also channelling poor households, and women in particular, into subordinate areas of the economy, which ultimately serve to maintain fundamental inequalities in Indian society. The initiatives may, in addition, be viewed as aspects of broader processes of financialisation. </jats:p
Transitions in coral reef accretion rates linked to intrinsic ecological shifts on turbid-zone nearshore reefs
Nearshore coral communities within turbid settings are typically perceived to have limited reef-building capacity. However, several recent studies have reported reef growth over millennial time scales within such environments and have hypothesized that depth-variable community assemblages may act as equally important controls on reef growth as they do in clear-water settings. Here, we explicitly test this idea using a newly compiled chronostratigraphic record (31 cores, 142 radiometric dates) from seven proximal (but discrete) nearshore coral reefs located along the central Great Barrier Reef (Australia). Uniquely, these reefs span distinct stages of geomorphological maturity, as reflected in their elevations below sea level. Integrated age-depth and ecological data sets indicate that contemporary coral assemblage shifts, associated with changing light availability and wave exposure as reefs shallowed, coincided with transitions in accretion rates at equivalent core depths. Reef initiation followed a regional ∼1 m drop in sea level (1200–800 calibrated yr B.P.) which would have lowered the photic floor and exposed new substrate for coral recruitment by winnowing away fine seafloor sediments. We propose that a two-way feedback mechanism exists where past growth history influences current reef morphology and ecology, ultimately driving future reef accumulation and morphological change. These findings provide the first empirical evidence that nearshore reef growth trajectories are intrinsically driven by changes in coral community structure as reefs move toward sea level, a finding of direct significance for predicting the impacts of extrinsically driven ecological change (e.g., coral-algal phase shifts) on reef growth potential within the wider coastal zone on the Great Barrier Reef
Preclinical evaluation of the proteasome inhibitor bortezomib in cancer therapy
Bortezomib is a highly selective, reversible inhibitor of the 26S proteasome that is indicated for single-agent use in the treatment of patients with multiple myeloma who have received at least 2 prior therapies and are progressing on their most recent therapy. Clinical investigations have been completed or are under way to evaluate the safety and efficacy of bortezomib alone or in combination with chemotherapy in multiple myeloma, both at relapse and presentation, as well as in other cancer types. The antiproliferative, proapoptotic, antiangiogenic, and antitumor activities of bortezomib result from proteasome inhibition and depend on the altered degradation of a host of regulatory proteins. Exposure to bortezomib has been shown to stabilize p21, p27, and p53, as well as the proapoptotic Bid and Bax proteins, caveolin-1, and inhibitor κB-α, which prevents activation of nuclear factor κB-induced cell survival pathways. Bortezomib also promoted the activation of the proapoptotic c-Jun-NH(2 )terminal kinase, as well as the endoplasmic reticulum stress response. The anticancer effects of bortezomib as a single agent have been demonstrated in xenograft models of multiple myeloma, adult T-cell leukemia, lung, breast, prostate, pancreatic, head and neck, and colon cancer, and in melanoma. In these preclinical in vivo studies, bortezomib treatment resulted in decreased tumor growth, angiogenesis, and metastasis, as well as increased survival and tumor apoptosis. In several in vitro and/or in vivo cancer models, bortezomib has also been shown to enhance the antitumor properties of several antineoplastic treatments. Importantly, bortezomib was generally well tolerated and did not appear to produce additive toxicities when combined with other therapies in the dosing regimens used in these preclinical in vivo investigations. These findings provide a rationale for further clinical trials using bortezomib alone or in combination regimens with chemotherapy, radiation therapy, immunotherapy, or novel agents in patients with hematologic malignancies or solid tumors
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