Genome sequence of an Australian kangaroo, Macropus eugenii, provides insight into the evolution of mammalian reproduction and development.

BACKGROUND: We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. RESULTS: The genome has been sequenced to 2 × coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. CONCLUSIONS: Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Data Linearization Activity for Undergraduate Analytical Chemistry Lectures

Throughout the undergraduate curriculum, students utilize linearized forms of nonlinear equations-from the Clausius-Clapeyron equation in general chemistry to the Michaelis-Menten equation in biochemistry. Presenting the linearized forms of equations as a fait accompli may be a lost opportunity to empower students with understanding the general process of linearization as an analytical tool. This work describes a series of activities that can be implemented and spaced throughout the analytical chemistry curriculum. The activities are low-cost and chemical-free, so they can be implemented in a lecture setting. Distributed practice allows students to attain familiarity with linearization, and the practical guided application in class provides real experience with the otherwise abstract mathematical idea

Data Linearization Activity For Undergraduate Analytical Chemistry Lectures

Throughout the undergraduate curriculum, students utilize linearized forms of nonlinear equations-from the Clausius-Clapeyron equation in general chemistry to the Michaelis-Menten equation in biochemistry. Presenting the linearized forms of equations as a fait accompli may be a lost opportunity to empower students with understanding the general process of linearization as an analytical tool. This work describes a series of activities that can be implemented and spaced throughout the analytical chemistry curriculum. The activities are low-cost and chemical-free, so they can be implemented in a lecture setting. Distributed practice allows students to attain familiarity with linearization, and the practical guided application in class provides real experience with the otherwise abstract mathematical idea

Identification Of Detergents For Forensic Fiber Analysis

Trace fibers are an important form of trace evidence, and identification of exogenous substances on textile fibers provides valuable information about the origin of the fiber. Laundering textiles can provide a unique fluorescent spectral signature of the whitening agent in the detergent that adsorbs to the fiber. Using fluorescence microscopy, the spectral characteristics of seven detergents adsorbed to single fibers drawn from laundered textiles were investigated, and principal component analysis of clusters was used to characterize the type of detergent on the fiber. On dyed nylon fibers, spectra from eight different detergent pairs could be resolved and washed validation fibers correctly classified. On dyed acrylic fibers, five different detergent pairs could be resolved and identified. Identification of the detergent type may prove useful in matching a trace fiber to its bulk specimen of origin

Predicting Accurate Fluorescent Spectra For High Molecular Weight Polycyclic Aromatic Hydrocarbons Using Density Functional Theory

The ability of density functional theory (DFT) methods to predict accurate fluorescence spectra for polycyclic aromatic hydrocarbons (PAHs) is explored. Two methods, PBE0 and CAM-B3LYP, are evaluated both in the gas phase and in solution. Spectra for several of the most toxic PAHs are predicted and compared to experiment, including three isomers of C24H14 and a PAH containing heteroatoms. Unusually high-resolution experimental spectra are obtained for comparison by analyzing each PAH at 4.2 K in an n-alkane matrix. All theoretical spectra visually conform to the profiles of the experimental data but are systematically offset by a small amount. Specifically, when solvent is included the PBE0 functional overestimates peaks by 16.1 ± 6.6 nm while CAM-B3LYP underestimates the same transitions by 14.5 ± 7.6 nm. These calculated spectra can be empirically corrected to decrease the uncertainties to 6.5 ± 5.1 and 5.7 ± 5.1 nm for the PBE0 and CAM-B3LYP methods, respectively. A comparison of computed spectra in the gas phase indicates that the inclusion of n-octane shifts peaks by +11 nm on average and this change is roughly equivalent for PBE0 and CAM-B3LYP. An automated approach for comparing spectra is also described that minimizes residuals between a given theoretical spectrum and all available experimental spectra. This approach identifies the correct spectrum in all cases and excludes approximately 80% of the incorrect spectra, demonstrating that an automated search of theoretical libraries of spectra may eventually become feasible

Portable Mercury Sensor For Tap Water Using Surface Plasmon Resonance Of Immobilized Gold Nanorods

The surface plasmon resonance of surface immobilized gold nanorods (Au NRs) was used to quantify mercury in tap water. Glass substrates were chemically functionalized with (3-mercaptopropyl)trimethoxysilane, which chemically bound the nanorods to produce a portable and sensitive mercury sensor. The analytical capabilities of the sensor were measured using micromolar mercury concentrations. Since the analytical response was dependent upon number of nanorods present, the limit of detection was 2.28×10-19 M mercury per nanorod. The possibility to using glass substrates with immobilized Au NRs is a significant step towards the analysis of mercury in tap water flows at this low concentration level. © 2012 Elsevier B.V

Single Fiber Identification With Nondestructive Excitation-Emission Spectral Cluster Analysis

Identification methods for single textile fibers are in demand for forensic applications, and nondestructive methods with minimal pretreatment have the greatest potential for utility. Excitation-emission luminescence data provide a three-dimensional matrix for comparison of single-fiber dyes, and these data are enhanced by principal component analysis and comparison of fibers using a statistical figure of merit. No dye extraction methods are required to sample the spectra from a single fiber. This approach has been applied to the analysis of single fibers to compare closely matched dye pairs, acid blue (AB) 25 and 41 and direct blue (DB) 1 and 53. In all cases, the accuracy of fiber identification was high and no false positive identifications were made. © 2014 American Chemical Society

Gold Nanorods For Surface Plasmon Resonance Detection Of Mercury (Ii) In Flow Injection Analysis

This article investigates the flow injection analysis of mercury (II) ions in tap water samples via surface Plasmon resonance detection. Quantitative analysis of mercury (II) is based on the chemical interaction of metallic mercury with gold nanorods immobilized on a glass substrate. A new flow cell design is presented with the ability to accommodate the detecting substrate in the sample compartment of commercial spectrometers. Two alternatives are here considered for mercury (II) detection, namely stop-flow and continuous flow injection analysis modes. The best limit of detection (2.4 ng mL-1) was obtained with the continuous flow injection analysis approach. The accurate determination of mercury (II) ions in samples of unknown composition is demonstrated with a fortified tap water sample. © 2014 Elsevier B.V. All rights reserved

Quantifying Sucralose In A Water-Treatment Wetlands: Service-Learning In The Analytical Chemistry Laboratory

Service-learning (SL) is an active learning approach that connects the knowledge a student acquires in the classroom to an application that benefits the community. Increasingly popular in the chemistry curriculum, service-learning is reported to provide student benefits including improved cognitive goals; increased academic, interpersonal, and leadership skills; increased ability to apply course concepts to real-world situations; and increased community engagement. For the work reported here, an analytical chemistry laboratory was modified to include a service-learning component with the goal of allowing students to apply their newly acquired analytical skills to relevant, real-world samples; to learn new analytical techniques; and to develop professional communication skills. Students implemented a study of the wastewater effluent at the Orlando Easterly Wetlands, an engineered water polishing facility that removes nutrients from treated wastewater. Students designed a sampling strategy, collected samples in the field, and performed standard analysis on the water, including pH, chloride, total dissolved solids, and phosphorus. Students also tested the water for the artificial sweetener, sucralose, and characterized the concentration throughout the flow path of the wetlands. Sucralose has been proposed as an indicator of contamination of natural waters by anthropogenic waste. This type of analysis has not been performed for this public utility until now, and the students shared the results in a public seminar. Student learning outcomes were compared to those in a conventional section, with SL students showing comparable subject mastery and improved self-efficacy