1,142 research outputs found
Frog Diversity and Population Trends in Andasibe, Madagascar
Facing immediate threats such as habitat loss, emerging infectious diseases, and climate change, the frog populations of the Madagascar rainforest, one of the richest amphibian diversity hotspots in the world, are an important focus for monitoring programs. This study focused on assessing the general diversity, key species population trends, and monitoring effectiveness of the Analamazaotra Forest Stationâs amphibian community, a population of over forty species within Andasibe, Madagascar. Building on a long-term monitoring program that began in 2012, visual encounter surveys were conducted over a two-week period in November 2015 along the edge and within the interior of the forest area managed by Association Mitsinjo. The current twenty-four transects were found to be an effective means of monitoring amphibian populations given species abundance curves and an individual assessment of each transect. Rank abundance curves, Simpsonâs Diversity Indexes, and a Jaccardâs Index were calculated as diversity assessment values using three years of data collection. From species evenness and richness assessments, the interior of the forest appeared to be unchanging in terms of diversity (stabilizing around a SDI of 0.91) while the forest edge had a decrease in diversity since 2013 (2013 SDI, 0.98; 2015 SDI, 0.82). These trends did not support expected diversity increases given the recovering status of the Analamazaotra Forest Station, since its protection in 2003, suggesting that these results may have been influenced by the seasonality effect of edge preference, the forestâs carrying capacity, and inconsistent surveys. For monitoring purposes, seasonality abundance baselines were calculated for the past four years of eleven key species. These eleven baseline species can be tracked in future years to assess population declines and judge habitat quality and forest health
Enzyme-Polymers Conjugated to Quantum-Dots for Sensing Applications
In the present research, the concept of developing a novel system based on polymer-enzyme macromolecules was tested by coupling carboxylic acid functionalized poly(vinyl alcohol) (PVA-COOH) to glucose oxidase (GOx) followed by the bioconjugation with CdS quantum-dots (QD). The resulting organic-inorganic nanohybrids were characterized by UV-visible spectroscopy, infrared spectroscopy, Photoluminescence spectroscopy (PL) and transmission electron microscopy (TEM). The spectroscopy results have clearly shown that the polymer-enzyme macromolecules (PVA-COOH/GOx) were synthesized by the proposed zero-length linker route. Moreover, they have performed as successful capping agents for the nucleation and constrained growth of CdS quantum-dots via aqueous colloidal chemistry. The TEM images associated with the optical absorption results have indicated the formation of CdS nanocrystals with estimated diameters of about 3.0 nm. The âblue-shiftâ in the visible absorption spectra and the PL values have provided strong evidence that the fluorescent CdS nanoparticles were produced in the quantum-size confinement regime. Finally, the hybrid system was biochemically assayed by injecting the glucose substrate and detecting the formation of peroxide with the enzyme horseradish peroxidase (HRP). Thus, the polymer-enzyme-QD hybrid has behaved as a nanostructured sensor for glucose detecting
One-step colloidal synthesis of biocompatible water-soluble ZnS quantum dot/chitosan nanoconjugates
Quantum dots (QDs) are luminescent semiconductor nanocrystals with great prospective for use in biomedical and environmental applications. Nonetheless, eliminating the potential cytotoxicity of the QDs made with heavy metals is still a challenge facing the research community. Thus, the aim of this work was to develop a novel facile route for synthesising biocompatible QDs employing carbohydrate ligands in aqueous colloidal chemistry with optical properties tuned by pH. The synthesis of ZnS QDs capped by chitosan was performed using a single-step aqueous colloidal process at room temperature. The nanobioconjugates were extensively characterised by several techniques, and the results demonstrated that the average size of ZnS nanocrystals and their fluorescent properties were influenced by the pH during the synthesis. Hence, novel 'cadmium-freeâ biofunctionalised systems based on ZnS QDs capped by chitosan were successfully developed exhibiting luminescent activity that may be used in a large number of possible applications, such as probes in biology, medicine and pharmacy
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The Clinical Utility of a Precision Medicine Blood Test Incorporating Age, Sex, and Gene Expression for Evaluating Women with Stable Symptoms Suggestive of Obstructive Coronary Artery Disease: Analysis from the PRESET Registry.
Background: Evaluating women with symptoms suggestive of coronary artery disease (CAD) remains challenging. A blood-based precision medicine test yielding an age/sex/gene expression score (ASGES) has shown clinical validity in the diagnosis of obstructive CAD. We assessed the effect of the ASGES on the management of women with suspected obstructive CAD in a community-based registry. Materials and Methods: The prospective PRESET (A Registry to Evaluate Patterns of Care Associated with the Use of CorusÂź CAD in Real World Clinical Care Settings) Registry (NCT01677156) enrolled 566 patients presenting with symptoms suggestive of stable obstructive CAD from 21 United States primary care practices from 2012 to 2014. Demographics, clinical characteristics, and referrals to cardiology or further functional and/or anatomical cardiac studies after ASGES testing were collected for this subgroup analysis of women from the PRESET Registry. Patients were followed for 1-year post-ASGES testing. Results: This study cohort included 288 women with a median age 57 years. The median body mass index was 29.2, with hyperlipidemia and hypertension present in 48% and 43% of patients, respectively. Median ASGES was 8.5 (range 1-40), with 218 (76%) patients having low (â€15) ASGES. Clinicians referred 9% (20/218) low ASGES versus 44% (31/70) elevated ASGES women for further cardiac evaluation (odds ratio 0.14, pâ<â0.0001, adjusted for patient demographics and clinical covariates). Across the score range, higher ASGES were associated with a higher likelihood of posttest cardiac referral. At 1-year follow-up, low ASGES women experienced fewer major adverse cardiac events than elevated ASGES women (1.3% vs. 4.2% respectively, pâ=â0.16). Conclusions: Incorporation of ASGES into the diagnostic workup demonstrated clinical utility by helping clinicians identify women less likely to benefit from further cardiac evaluation
Latest Trends in the Heroin Epidemic and the Responsibility of the Pharmacist in Controlling Heroin Abuse
Over the last few years, there has been an exponential increase in morbidity and mortality associated with heroin abuse. The current rise in heroin abuse and overdose is attributed to widespread use and abuse of prescription opioids, which can produce significant euphoric effects in humans. In fact, reports suggest that heroin abusers initially become addicted to prescription opioids but subsequently switch to heroin because it is cheaper and more easily available than prescription opioids. Over the years, the purity of heroin available for illicit use has been on the decline. Smugglers and heroin vendors have started mixing heroin with other clandestinely prepared, potent, analgesic opioids such as fentanyl. Fentanyl is 30 to 50 times more potent than heroin, and the combination can be quite lethal to abusers due to the increased potency and effects on the body\u27s respiratory centers which may result in death. This review will mainly focus on some of the recent trends in heroin abuse and recent changes in laws with respect to dispensing and possession of naloxone, an effective antidote against heroin overdose. Finally, the role of the pharmacist in countering the current heroin epidemic by recognizing at-risk populations and providing the proper resources to addicts to prevent further heroin/opioid-related overdose fatalities will be discussed
One-Pot Aqueous Synthesis of Fluorescent Ag-In-Zn-S Quantum Dot/Polymer Bioconjugates for Multiplex Optical Bioimaging of Glioblastoma Cells
Cancer research has experienced astonishing advances recently, but cancer remains a major threat because it is one of the leading causes of death worldwide. Glioblastoma (GBM) is the most malignant brain tumor, where the early diagnosis is vital for longer survival. Thus, this study reports the synthesis of novel water-dispersible ternary AgInS2 (AIS) and quaternary AgInS2-ZnS (ZAIS) fluorescent quantum dots using carboxymethylcellulose (CMC) as ligand for multiplexed bioimaging of malignant glioma cells (U-87 MG). Firstly, AgInS2 core was prepared using a one-pot aqueous synthesis stabilized by CMC at room temperature and physiological pH. Then, an outer layer of ZnS was grown and thermally annealed to improve their optical properties and split the emission range, leading to core-shell alloyed nanostructures. Their physicochemical and optical properties were characterized, demonstrating that luminescent monodispersed AIS and ZAIS QDs were produced with average sizes of 2.2ânm and 4.3ânm, respectively. Moreover, the results evidenced that they were cytocompatible using in vitro cell viability assays towards human embryonic kidney cell line (HEK 293T) and U-87 MG cells. These AIS and ZAIS successfully behaved as fluorescent nanoprobes (red and green, resp.) allowing multiplexed bioimaging and biolabeling of costained glioma cells using confocal microscopy
Component tree analysis of cystovirus Ï6 nucleocapsid Cryo-EM single particle reconstructions
The 3-dimensional structure of the nucleocapsid (NC) of bacteriophage Ï6 is described utilizing component tree analysis, a topological and geometric image descriptor. The component trees are derived from density maps of cryo-electron microscopy single particle reconstructions. Analysis determines position and occupancy of structure elements responsible for RNA packaging and transcription. Occupancy of the hexameric nucleotide triphosphorylase (P4) and RNA polymerase (P2) are found to be essentially complete in the NC. The P8 protein lattice likely fixes P4 and P2 in place during maturation. We propose that the viral procapsid (PC) is a dynamic structural intermediate where the P4 and P2 can attach and detach until held in place in mature NCs. During packaging, the PC expands to accommodate the RNA, and P2 translates from its original site near the inner 3-fold axis (20 sites) to the inner 5-fold axis (12 sites) with excess P2 positioned inside the central region of the NC
Standardized Patient Assessment of Communications in Pharmacy and Medical Students
Use of activities (i.e. objective structured clinical examinations, or OSCEs) involving standardized patients (SPs) is a commonly used method of assessing communication skills in health sciences education is through the. The use of SPs was associated with higher scores on communications assessments and significant improvements on many subsections of a communications assessment tool in pharmacy students. However, these studies used faculty (not the SPs) to assess the students. While the use of SPs as direct evaluators of communication skills is recognized in medical education it is poorly defined in pharmacy education. In addition, interprofessional education (IPE) environments (including the one here at the University of New Mexico) are likely to use the same SPs to help train and assess students coming from an array of health professional programs. This project studied the utility of using SPs as evaluators of communication skills in pharmacy students and determined the extent of the difference in SP assessment of communication skills in pharmacy and medical students. We believe such knowledge will be helpful for designing and assessing IPE activities that involve SP interactions
Exploring relationships between canopy architecture, light distribution and photosynthesis in contrasting rice genotypes using 3D canopy reconstruction
The arrangement of leaf material is critical in determining the light environment, and subsequently the photosynthetic productivity of complex crop canopies. However, links between specific canopy architectural traits and photosynthetic productivity across a wide genetic background are poorly understood for field grown crops. The architecture of five genetically diverse rice varieties - four parental founders of a multi-parent advanced generation intercross (MAGIC) population plus a high yielding Philippine variety (IR64) - was captured at two different growth stages using a method for digital plant reconstruction based on stereocameras. Ray tracing was employed to explore the effects of canopy architecture on the resulting light environment in high-resolution, whilst gas exchange measurements were combined with an empirical model of photosynthesis to calculate an estimated carbon gain and total light interception. To further test the impact of different dynamic light patterns on photosynthetic properties, an empirical model of photosynthetic acclimation was employed to predict the optimal light-saturated photosynthesis rate (Pmax) throughout canopy depth, hypothesising that light is the sole determinant of productivity in these conditions. First we show that a plant type with steeper leaf angles allows more efficient penetration of light into lower canopy layers and this, in turn, leads to a greater photosynthetic potential. Second the predicted optimal Pmax responds in a manner that is consistent with fractional interception and leaf area index across this germplasm. However measured Pmax, especially in lower layers, was consistently higher than the optimal Pmax indicating factors other than light determine photosynthesis profiles. Lastly, varieties with more upright architecture exhibit higher maximum quantum yield of photosynthesis indicating a canopy-level impact on photosynthetic efficiency
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