2,961 research outputs found
Novel mechanistic insight into ciliary regulation: old pathways yield new mechanisms
Cilia are structures present on most eukaryotic cells which provide important signaling and motile components to cells from early development to fully differentiated and matured cells. Regulation of these structures is critical to proper functioning of the cell and is known to be tied to the cell cycle. Preparation for ciliary assembly following cell cycle exit and ciliary disassembly following cell cycle reentry requires components throughout the cell body and within the cilium to facilitate this process. Here I identify how the cell adapts to ensure modifications to cilia occur for assembly or disassembly using the model organism Chlamydomonas reinhardtii. By chemically and genetically inhibiting map kinase phosphatases in Chlamydomonas which most closely match mammalian DUSP6, the phosphatase for ERK1/2 in the canonical cell cycle control ERK pathway, cilia shorten and fail to assemble. We find that DUSP6 inhibition also results in inhibited ciliary protein entry, altered protein localization to the transition zone, inhibited membrane trafficking or through inhibited cytoskeletal microtubule reorganization. Additionally, we find that maintaining cytoplasmic microtubules and short tracks of cilia can allow for cilia to immediately assemble within 5 minutes post deciliation. Together, this data provides a comprehensive view of how the cell induces changes outside of the cilium to regulate this critical signaling organelle
The urban/suburban wildlife survey volunteer project
This study examined attitudes of volunteers in the Urban/Suburban Volunteer Project. Volunteers for this project surveyed for bird species for the New Jersey Endangered and Nongame Species Program in Urban New Jersey areas. This project was considered unsuccessful by the Endangered and Nongame Species staff. By analyzing a volunteer project that was not as successful as hoped, volunteer managers can learn from this and apply the findings to their own projects. The purpose of this study was to find out what volunteers thought of the Urban/Suburban Volunteer Project.
Questionnaires were sent to the known population, a total of 25 questionnaires were returned for a return rate of 60 percent. Questionnaires contained both closed-ended and open-ended questions and these were analyzed.
It was found that most volunteers found the surveys to be a rewarding experience and would participate in the project again. Some volunteers found the surveys time consuming and overwhelming. Most volunteers were highly skilled birders, those with less skills would have found the surveys difficult. The problem is that there were not enough volunteers participating in the Urban/Suburban Project to achieve the data needs of the ENSP program
Probit models for capture-recapture data subject to imperfect detection, individual heterogeneity and misidentification
As noninvasive sampling techniques for animal populations have become more
popular, there has been increasing interest in the development of
capture-recapture models that can accommodate both imperfect detection and
misidentification of individuals (e.g., due to genotyping error). However,
current methods do not allow for individual variation in parameters, such as
detection or survival probability. Here we develop misidentification models for
capture-recapture data that can simultaneously account for temporal variation,
behavioral effects and individual heterogeneity in parameters. To facilitate
Bayesian inference using our approach, we extend standard probit regression
techniques to latent multinomial models where the dimension and zeros of the
response cannot be observed. We also present a novel Metropolis-Hastings within
Gibbs algorithm for fitting these models using Markov chain Monte Carlo. Using
closed population abundance models for illustration, we re-visit a DNA
capture-recapture population study of black bears in Michigan, USA and find
evidence of misidentification due to genotyping error, as well as temporal,
behavioral and individual variation in detection probability. We also estimate
a salamander population of known size from laboratory experiments evaluating
the effectiveness of a marking technique commonly used for amphibians and fish.
Our model was able to reliably estimate the size of this population and
provided evidence of individual heterogeneity in misidentification probability
that is attributable to variable mark quality. Our approach is more
computationally demanding than previously proposed methods, but it provides the
flexibility necessary for a much broader suite of models to be explored while
properly accounting for uncertainty introduced by misidentification and
imperfect detection. In the absence of misidentification, our probit
formulation also provides a convenient and efficient Gibbs sampler for Bayesian
analysis of traditional closed population capture-recapture data.Comment: Published in at http://dx.doi.org/10.1214/14-AOAS783 the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Pengelolaan dan Pengembangan Usaha Retail dan Trading pada PT. Xyz di Jawa Timur
Di Indonesia UMKM (Usaha Mikro, Kecil dan Menengah) memiliki peran yang sangat penting sebagai salah satu penunjang utama kehidupan perekonomian di Indonesia. PT. XYZ merupakan salah satu usaha menengah yang bergerak dalam bidang otomotif sepeda motor. Penelitian ini membahas mengenai pengelolaan dan pengembangan usaha retail dan trading pada PT. XYZ, serta mendiskripsikan lingkungan internal dan eksternal Perusahaan pada PT. XYZ, serta rencana pengembangan bisnis PT. XYZ.Teknik analisa yang digunakan dalam penelitian ini adalah kualitatif deskriptif, dan untuk penentuan informan dalam penelitian ini digunakan purposive technique. Purposive technique digunakan untuk mendapatkan data yang diperlukan dalam penelitian.Dari hasil penelitian yang telah dilakukan dapat disimpulkan bahwa pengelolaan Perusahaan pada PT. XYZ memiliki kendala pada aspek keuangan, teknologi informasi, persaingan yang semakin ketat, dan menghadapi produk pengganti. Melalui analisa tersebut, disimpulkan bahwa formulasi strategi yang dapat mengembangkan bisnis ini adalah strategi diferensiasi, yaitu dengan memberi benefit ekstra yang dirasakan oleh konsumen. Kata kunci: UMKM, Pengelolaan Usaha, Pengembangan Usaha, dan Strategi Diferensiasi
Prosomal-width-to-weight relationships in American horseshoe crabs (Limulus polyphemus): examining conversion factors used to estimate landings
Horseshoe crabs (Limulus polyphemus) are valued by many
stakeholders, including the commercial fishing industry, biomedical companies, and environmental interest groups. We designed a study to test the accuracy of the conversion factors that were used by NOAA Fisheries and state agencies to estimate horseshoe crab landings before mandatory
reporting that began in 1998. Our results indicate that the NOAA Fisheries conversion factor consistently overestimates the weight of male horseshoe crabs, particularly those from New England populations. Because of the inaccuracy of this and other conversion factors, states are now mandated to report the number (not biomass) and sex of landed horseshoe
crabs. However, accurate estimates of biomass are still necessary for use in prediction models that are being developed to better manage the horseshoe crab fishery. We recommend that managers use the conversion factors presented in this study to convert current landing data from numbers to biomass of harvested horseshoe crabs
for future assessments
Teacher education and the teachers’ competencies:a view from primary school pre-service teachers’ perceptions
Abstract. Scholars understand competencies as a mixture of abilities, knowledge, skills, and behaviors. Equally, it can be understood as a measure of one’s performance. Thus, varied catalogs of teachers’ competencies are discussed in the academical set. However, Ding (2016), categorized eight key competencies for the primary teacher. They are: Pedagogical competencies; Curriculum Knowledge; Assessment; Classroom Management; Culture and Cross-Culture competencies; Ethical and Professional Values; Social, Emotional and Communication; and Life-long Learning competencies. This set of competencies was chosen as the base of data collection and helped to categorize the data in the data analysis procedure.
The aim was to explore the teachers’ competencies in Primary Teacher Education based on the pre-service teachers’ perceptions and to explore the competencies required for the teaching practice in Primary Schools, making a comparison between work field and teacher training under the competencies theme. The study was conducted using a qualitative method, and the data was collected via semi-structured one-on-one interviews and content analyzed. The chosen method for sampling was the non-probabilistic convenience one. The research questions were: What are the pre-service teachers’ perceptions of the competencies the Teacher Education provides? What are the competencies the work requires according to the Primary school curriculum? And what are the differences and similarities between the pre-service teachers’ perceptions of competencies they have gained and the competencies the Primary Education field actually requires?
As results, this study showed that there is a difference between the competencies pre-service teachers are learning in Teacher Education and the competencies they need in the working field. Also, the relevance of practice was explored as it helps bridge the gap that exists between theoretical knowledge and challenges that are encountered in the classroom. The relatively short time for teaching practice, the low acquisition of teachers’ competencies from the student-teachers, and the lack of a mentor’s support from University or the school are some of the issues the pre-service teachers are facing that are establishing this gap
Terrestrial Consequences of Spectral and Temporal Variability in Ionizing Photon Events
Gamma-Ray Bursts (GRBs) directed at Earth from within a few kpc may have
damaged the biosphere, primarily though changes in atmospheric chemistry which
admit greatly increased Solar UV. However, GRBs are highly variable in spectrum
and duration. Recent observations indicate that short (~0.1 s) burst GRBs,
which have harder spectra, may be sufficiently abundant at low redshift that
they may offer an additional significant effect. A much longer timescale is
associated with shock breakout luminosity observed in the soft X-ray (~10^3 s)
and UV (~10^5 s) emission, and radioactive decay gamma-ray line radiation
emitted during the light curve phase of supernovae (~10^7 s). Here we
generalize our atmospheric computations to include a broad range of peak photon
energies and investigate the effect of burst duration while holding total
fluence and other parameters constant. The results can be used to estimate the
probable impact of various kinds of ionizing events (such as short GRBs, X-ray
flashes, supernovae) upon the terrestrial atmosphere. We find that the ultimate
intensity of atmospheric effects varies only slightly with burst duration from
10^-1 s to 10^8 s. Therefore, the effect of many astrophysical events causing
atmospheric ionization can be approximated without including time development.
Detailed modeling requires specification of the season and latitude of the
event. Harder photon spectra produce greater atmospheric effects for spectra
with peaks up to about 20 MeV, because of greater penetration into the
stratosphere.Comment: 30 pages, to be published in ApJ. Replaced for conformity with
published version, including correction of minor typos and updated reference
Integrated Assessment of Irrigation Water Quality Based on Harrington\u27s Desirability Function
It was proposed the integrated approach to the irrigation water assessment as its quality index IWQI. This criteria is united the quantitative assessment of different risks such as soil sodicity, plant toxicity, biofilm formation in drippers of irrigation systems etc. It is proposed to combine agronomic, ecological and technological requirements to the irrigation water using a generalized Harrington\u27s desirability function (HDF). Within the framework of this concept, it was developed the scales of particular HDF for physico-chemical indicators, SAR values, and the Stebler\u27s irrigation coefficient. IWQI was determined for the assessment of water quality for irrigation purpose on the examples of 3 dug wells located on the Agronomic Experimental station of National University of Life and Environmental Sciences of Ukraine (Pshenichne village, Kiev region). It is shown that water quality varies considerably (from 56 till 85%)
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Communication interventions to promote the public's awareness of antibiotics: a systematic review.
BackgroundInappropriate antibiotic use is implicated in antibiotic resistance and resultant morbidity and mortality. Overuse is particularly prevalent for outpatient respiratory infections, and perceived patient expectations likely contribute. Thus, various educational programs have been implemented to educate the public.MethodsWe systematically identified public-directed interventions to promote antibiotic awareness in the United States. PubMed, Google Scholar, Embase, CINAHL, and Scopus were queried for articles published from January 1996 through January 2016. Two investigators independently assessed titles and abstracts of retrieved articles for subsequent full-text review. References of selected articles and three review articles were likewise screened for inclusion. Identified educational interventions were coded for target audience, content, distribution site, communication method, and major outcomes.ResultsOur search yielded 1,106 articles; 34 met inclusion criteria. Due to overlap in interventions studied, 29 distinct educational interventions were identified. Messages were primarily delivered in outpatient clinics (N = 24, 83%) and community sites (N = 12, 41%). The majority included clinician education. Antibiotic prescription rates were assessed for 22 interventions (76%). Patient knowledge, attitudes, and beliefs (KAB) were assessed for 10 interventions (34%). Similar rates of success between antibiotic prescription rates and patient KAB were reported (73 and 70%, respectively). Patient interventions that did not include clinician education were successful to increase KAB but were not shown to decrease antibiotic prescribing. Three interventions targeted reductions in Streptococcus pneumoniae resistance; none were successful.ConclusionsMessaging programs varied in their designs, and many were multifaceted in their approach. These interventions can change patient perspectives regarding antibiotic use, though it is unclear if clinician education is also necessary to reduce antibiotic prescribing. Further investigations are needed to determine the relative influence of interventions focusing on patients and physicians and to determine whether these changes can influence rates of antibiotic resistance long-term
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