263 research outputs found
Estimating the Age of a Bloodstain Using Mitochondrial rRNA
DNA evidence is considered the gold standard of evidence in forensic investigations. DNA is one of the most highly discriminatory pieces of evidence found at crime scenes and can link individuals to scenes. It is not relied on to perform temporal estimates to help establish a timeline for when a crime took place. Previous studies have shown that measurement of the degradation of RNA is a potential tool to establish a temporal estimate of when a blood sample was left at a crime scene. This experiment attempts to improve on previous RNA degradation studies by evaluating the validity of mitochondrial ribosomal RNA and quantitative PCR as method of age determination of a bloodstain. This approach was unsuccessful in estimating the age of a bloodstain due to the lack of consistent degradation as samples aged. The expected starting ratio of mitochondrial ribosomal RNA was also found to be inconsistent. While this approach was unsuccessful, it provides insights that may allow for further refinement of this assay to estimate the age of a bloodstain
Visual control of refuge recognition in the whip spider \u3ci\u3ePhrynus marginemaculatus\u3c/i\u3e
Amblypygids, or whip spiders, are nocturnally active arachnids which live in structurally complex environments. Whip spiders are excellent navigators that can re-locate a home refuge without relying on visual input. Therefore, an open question is whether visual input can control any aspect of whip spider spatial behavior. In the current study, Phrynus marginemaculatus were trained to locate an escape refuge by discriminating between differently oriented black and white stripes placed either on the walls of a testing arena (frontal discrimination) or on the ceiling of the same testing arena (overhead discrimination). Regardless of the placement of the visual stimuli, the whip spiders were successful in learning the location of the escape refuge. In a follow-up study of the overhead discrimination, occluding the median eyes was found to disrupt the ability of the whip spiders to locate the shelter. The data support the conclusion that whip spiders can rely on vision to learn and recognize an escape shelter. We suggest that visual inputs to the brainâs mushroom bodies enable this ability
Problems With the Vortex-Boson Mapping in 1+1 Dimensions
Using the well known boson mapping, we relate the transverse magnetic
susceptibility of a system of flux vortices in 1+1 dimensions to an
appropriately defined conductivity of a one-dimensional boson system. The tilt
response for a system free of disorder is calculated directly, and it is found
that a subtle order of limits is required to avoid deceptive results.Comment: 4 Pages (REVTeX 3.0). Postscript file for this paper is available on
the World Wide Web at http://cmtw.harvard.edu/~simon/
A Review of Basic Energy Reconstruction Techniques in Liquid Xenon and Argon Detectors for Dark Matter and Neutrino Physics Using NEST
Detectors based upon the noble elements, especially liquid xenon as well as
liquid argon, as both single- and dual-phase types, require reconstruction of
the energies of interacting particles, both in the field of direct detection of
dark matter (Weakly Interacting Massive Particles or WIMPs, axions, etc.) and
in neutrino physics. Experimentalists, as well as theorists who
reanalyze/reinterpret experimental data, have used a few different techniques
over the past few decades. In this paper, we review techniques based on solely
the primary scintillation channel, the ionization or secondary channel
available at non-zero drift electric fields, and combined techniques that
include a simple linear combination and weighted averages, with a brief
discussion of the applications of profile likelihood, maximum likelihood, and
machine learning. Comparing results for electron recoils (beta and gamma
interactions) and nuclear recoils (primarily from neutrons) from the Noble
Element Simulation Technique (NEST) simulation to available data, we confirm
that combining all available information generates higher-precision means,
lower widths (energy resolution), and more symmetric shapes (approximately
Gaussian) especially at keV-scale energies, with the symmetry even greater when
thresholding is addressed. Near thresholds, bias from upward fluctuations
matters. For MeV-GeV scales, if only one channel is utilized, an
ionization-only-based energy scale outperforms scintillation; channel
combination remains beneficial. We discuss here what major collaborations use.Comment: 42 Pages, 2 Tables, 11 Figures, 13 Equation
Adipocytes promote pancreatic cancer cell proliferation via glutamine transfer
AbstractAdipocytes promote progression of multiple cancers, but their role in pancreatic intraepithelial neoplasia (PanIN) and ductal adenocarcinoma (PDAC) is poorly defined. Nutrient transfer is a mechanism underlying stromal cell-cancer crosstalk. We studied the role of adipocytes in regulating in vitro PanIN and PDAC cell proliferation with a focus on glutamine metabolism. Murine 3T3L1 adipocytes were used to model adipocytes. Cell lines derived from PKCY mice were used to model PanIN and PDAC. Co-culture was used to study the effect of adipocytes on PanIN and PDAC cell proliferation in response to manipulation of glutamine metabolism. Glutamine secretion was measured with a bioanalyzer. Western blotting was used to study the effect of PanIN and PDAC cells on expression of glutamine-related enzymes in adipocytes. Adipocytes promote proliferation of PanIN and PDAC cells, an effect that was amplified in nutrient-poor conditions. Adipocytes secrete glutamine and rescue PanIN and PDAC cell proliferation in the absence of glutamine, an effect that was glutamine synthetase-dependent and involved PDAC cell-induced down-regulation of glutaminase expression in adipocytes. These findings suggest glutamine transfer as a potential mechanism underlying adipocyte-induced PanIN and PDAC cell proliferation
Adult North Star Network (ANSN): Consensus Document for Therapists Working with Adults with Duchenne Muscular Dystrophy (DMD) - Therapy Guidelines
BACKGROUND
The survival of people with Duchenne Muscular Dystrophy (DMD) significantly increased due to improvements in standards of care (SOC) [1]. Consequently, DMD has evolved from a paediatric disease to a severe, chronic, multisystem, adult condition. The published international standards of care advocate specialist multidisciplinary health monitoring through proactive, anticipatory approaches to slow down the effects of the disease and allow advanced, informed decision-making [1â3]. Therapy starts as soon as the diagnosis is made and plays a vital role in symptom management in individuals to improve function, participation and effective quality of life. Therapy interventions for management, differ depending on the setting in which the care is being provided, specifically in terms of the expertise within the teams and resources available within these settings.
People with DMD find that when they transition to adult services there is a dearth of expertise and limited access to therapy services. The survey conducted in the UK highlighted substantial differences between the care received by adults and children with the condition [2]. A large proportion of adults with DMD reported increased difficulties with access to professional physiotherapy, particularly at transition from childhood to adulthood. Additionally, having their functional abilities assessed regularly or receiving professional physiotherapy in general were both significantly more difficult to achieve within adult services in the UK. Furthermore, some of the major problems expressed by adults with DMD were mobility and transportation as well as, getting involved in leisure activities and work [3]. Therefore, while pediatric services are predominantly family-centred, after transition the paradigm of patient care changes towards individual-centred with focus on different therapy goals. Those become more tailored to the individualsâ needs, balancing quality of life and management options.This document is aimed at providing guidelines for physiotherapy, occupational therapy and speech and language considerations.
The âAdult North Star Networkâ (ANSN) was founded in 2015 to advance care of adults with DMD living in the UK and to develop a prospective natural history database. There are currently 28 adult centres within the network, caring for at least 700 DMD patients. Transition age is varied depending on services and is generally between the ages of 16 to 18. There is a wide range of severity affecting people with DMD transitioned to adult services, those who are steroid naive will have been permanent wheelchair users for many years and have profound muscle weakness. On the other hand, steroid treated patients will most commonly have good upper limb function, and some maybe ambulant at the time of transition. Additionally the specific type of genetic mutation, compliance to therapy and environmental factors may play a role in disease progression and presentation at transition.
The aim of these guidelines is to support therapists working with adults with DMD with little or no experience to assist their clinical practice. Whilst the recommendations can be adopted by other health care systems in the world, we appreciate it will depend on resource availability
High-resolution cryo-electron microscopy structure of photosystem II from the mesophilic cyanobacterium, Synechocystis sp. PCC 6803
Photosystem II (PSII) enables global-scale, light-driven water oxidation. Genetic manipulation of PSII from the mesophilic cyanobacterium Synechocystis sp. PCC 6803 has provided insights into the mechanism of water oxidation; however, the lack of a highresolution structure of oxygen-evolving PSII from this organism has limited the interpretation of biophysical data to models based on structures of thermophilic cyanobacterial PSII. Here, we report the cryo-electron microscopy structure of PSII from Synechocystis sp. PCC 6803 at 1.93-Ă
resolution. A number of differences are observed relative to thermophilic PSII structures, including the following: the extrinsic subunit PsbQ is maintained, the C terminus of the D1 subunit is flexible, some waters near the active site are partially occupied, and differences in the PsbV subunit block the Large (O1) water channel. These features strongly influence the structural picture of PSII, especially as it pertains to the mechanism of water oxidation
Connective Memory Work on Justice for Mike Brown
This chapter addresses what I term the "connective memory work" carried out on Facebook page dedicated to achieving justice for Michael Brown, an African America teenager whose death at the gun of white police officer Darren Wilson in early August 2014 led to the Ferguson protests. The chapter outlines four types of connective memory work evident on the page. These types include the âmemetic resurrectionâ that involved the appropriation of iconic historical imagery alongside those of networked commemoration, digital archiving and curation, and crowd reconstruction. Central to this contribution the call to rethink the digital memory work practices of activists so as to integrate a concern for the agency of social media platforms themselves.<br/
Do issues matter? Anti-austerity protestsâ composition, values, and action repertoires compared
An important wave of anti-austerity protests has swept across Western Europe in recent years. We can thus distinguish between three different types of protest occurring in Western Europe recently: âoldâ issue protests, relating to the trade union and labor movement; ânewâ issue protests, relating to culture and identity issues; anti-austerity protests, emerging directly in reaction to austerity measures and cuts enacted in the current period. Following previous literature, we hypothesize that anti-austerity protests have attracted a new constituency to the streets and that they will be different from both âoldâ and ânewâ protests in terms of their social composition, value orientations, and action repertoires. We expect anti-austerity protesters to be on the whole younger, and in more precarious working conditions, to be more concerned with economic over social issues, but also to be considerably less institutionalized and embedded in organizational networks, and to have fewer experiences of previous extra-institutional participation. We test these hypotheses by analyzing a unique and novel dataset containing data from over 10,000 protestors from 72 demonstrations (2009â2013). Our results lend broad support to our hypotheses with the exception of the idea that âprecarityâ forms a new social base for anti-austerity protests
Combining modeling tools to identify conservation priority areas: A case study of the last large-bodied avian frugivore in the Atlantic Forest
Applicability of modeling tools to tackle conservation problems is key for conservation planning. However, modeling papers regarding real-world conservation issues are scarce. Here, we combined two modeling tools to identify priority areas in the Brazilian Atlantic Forest, focusing on the last large-bodied frugivorous bird in the region, the red-billed curassow (Crax blumenbachii). We used population viability analysis (PVA) to determine (1) the minimum viable population size under different hunting scenarios; and (2) the minimum critical forest patch size required to maintain viable populations. We used ecological niche modeling (ENM) to identify remnants that retain suitable environmental conditions to ensure the long-term persistence of this species. We overlapped the outputs from PVA and ENM models to identify priority areas for curassows. Under our best-case scenario, 56 individuals would suffice to maintain a viable population and 71 forest patches located within the species' known range are above the critical size of 3141âŻha. In the worst-case scenario, at least 138 individuals would be required to maintain a viable population in forest patches larger than 9500âŻha, corresponding to only 20 Atlantic Forest fragments within the species range. Among these, 17 presented median habitat suitability values higher than 0.70, eight of which were selected as priority areas for law enforcement and nine as priority areas for reintroduction. We encourage conservation biologists and land managers to combine modeling tools which can be guided by our conservation planning framework. This approach is promising to inform long-term conservation planning of a flagship species and its entire ecosystem
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