132 research outputs found
Evaluation of Dynamic Cell Processes and Behavior Using Video Bioinformatics Tools
Just as body language can reveal a personâs state of well-being, dynamic changes in cell behavior and
morphology can be used to monitor processes in cultured cells. This chapter discusses how CL-Quant
software, a commercially available video bioinformatics tool, can be used to extract quantitative data on:
(1) growth/proliferation, (2) cell and colony migration, (3) reactive oxygen species (ROS) production, and
(4) neural differentiation. Protocols created using CL-Quant were used to analyze both single cells and
colonies. Time-lapse experiments in which different cell types were subjected to various chemical
exposures were done using Nikon BioStations. Proliferation rate was measured in human embryonic stem
cell colonies by quantifying colony area (pixels) and in single cells by measuring confluency (pixels).
Colony and single cell migration were studied by measuring total displacement (distance between the
starting and ending points) and total distance traveled by the colonies/cells. To quantify ROS production,
cells were pre-loaded with MitoSOX Redâą, a mitochondrial ROS (superoxide) indicator, treated with
various chemicals, then total intensity of the red fluorescence was measured in each frame. Lastly, neural
stem cells were incubated in differentiation medium for 12 days, and time lapse images were collected
daily. Differentiation of neural stem cells was quantified using a protocol that detects young neurons. CLQuant
software can be used to evaluate biological processes in living cells, and the protocols developed in
this project can be applied to basic research and toxicological studies, or to monitor quality control in
culture facilities
Joint Resummation for Higgs Production
We study the application of the joint resummation formalism to Higgs
production via gluon-gluon fusion at the LHC, defining inverse transforms by
analytic continuation. We work at next-to-leading logarithmic accuracy. We find
that at low Q_T the resummed Higgs Q_T distributions are comparable in the
joint and pure-Q_T formalisms, with relatively small influence from threshold
enhancement in this range. We find a modest (about ten percent) decrease in the
inclusive cross section, relative to pure threshold resummation.Comment: 22 pages, LaTeX, 5 figures as eps file
Researching men who pay for sex: Using online methods for recruiting and interviewing
The use of online tools for recruitment and data collection are increasingly offering researchers access to hard to reach groups, and providing data about sensitive topics that were previously inaccessible to the research community. In this article, drawing on the experience of researching men who pay for sex with female sex workers in the United Kingdom, I explore the complexities of conducting online research, arguing that online research is indeed a valuable research tool, but that it should not be seen as the âeasyâ option. This article outlines my rationale for using online methods and how traditional interview and recruitment practices and ethical issues were altered by this approach. A discussion of transformations in space and time follows. Finally, I reflect on how engaging with certain methods can reveal insights into the practices of those we research
Centrioles: active players or passengers during mitosis?
Centrioles are cylinders made of nine microtubule (MT) triplets present in many eukaryotes. Early studies, where centrosomes were seen at the poles of the mitotic spindle led to their coining as âthe organ for cell divisionâ. However, a variety of subsequent observational and functional studies showed that centrosomes might not always be essential for mitosis. Here we review the arguments in this debate. We describe the centriole structure and its distribution in the eukaryotic tree of life and clarify its role in the organization of the centrosome and cilia, with an historical perspective. An important aspect of the debate addressed in this review is how centrioles are inherited and the role of the spindle in this process. In particular, germline inheritance of centrosomes, such as their de novo formation in parthenogenetic species, poses many interesting questions. We finish by discussing the most likely functions of centrioles and laying out new research avenues
ChitosanâStarchâKeratin composites: Improving thermo-mechanical and degradation properties through chemical modification
The lysozyme test shows an improved in the degradability rate, the weight loss of the ïŹlms at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all ïŹlms show a biodegradable character depending on keratin type and chemical modiïŹcation. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosanâstarch ïŹlms with sustainable featuresChitosanâstarch polymers are reinforced with diïŹerent keratin materials obtained from chicken feather. Keratin materials are treated with sodium hydroxide; the modiïŹed surfaces are rougher in comparison with untreated surfaces, observed by Scanning Electron Microscopy. The results obtained by DiïŹerential Scanning Calorimetry show an increase in the endothermic peak related to water evaporation of the ïŹlms from 92 °C (matrix) up to 102â114 °C (reinforced composites). Glass transition temperature increases from 126 °C in the polymer matrix up to 170â200 °C for the composites. Additionally, the storage modulus in the composites is enhanced up to 1614 % for the composites with modiïŹed ground quill, 2522 % for composites with modiïŹed long ïŹber and 3206 % for the composites with modiïŹed short ïŹber. The lysozyme test shows an improved in the degradability rate, the weight loss of the ïŹlms at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all ïŹlms show a biodegradable character depending on keratin type and chemical modiïŹcation. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosanâstarch ïŹlms with sustainable featuresUniversidad AutĂłnoma del Estado de MĂ©xico TecnolĂłgico Nacional de MĂ©xico, Instituto TecnolĂłgico de QuerĂ©taro Universidad Nacional AutĂłnoma de MĂ©xico TecnolĂłgico Nacional de MĂ©xico, Instituto TecnolĂłgico de Celaya Universidad AutĂłnoma de Cd. JuĂĄre
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LEARN: A multi-centre, cross-sectional evaluation of Urology teaching in UK medical schools.
OBJECTIVE: To evaluate the status of UK undergraduate urology teaching against the British Association of Urological Surgeons (BAUS) Undergraduate Syllabus for Urology. Secondary objectives included evaluating the type and quantity of teaching provided, the reported performance rate of General Medical Council (GMC)-mandated urological procedures, and the proportion of undergraduates considering urology as a career. MATERIALS AND METHODS: LEARN was a national multicentre cross-sectional study. Year 2 to Year 5 medical students and FY1 doctors were invited to complete a survey between 3rd October and 20th December 2020, retrospectively assessing the urology teaching received to date. Results are reported according to the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). RESULTS: 7,063/8,346 (84.6%) responses from all 39 UK medical schools were included; 1,127/7,063 (16.0%) were from Foundation Year (FY) 1 doctors, who reported that the most frequently taught topics in undergraduate training were on urinary tract infection (96.5%), acute kidney injury (95.9%) and haematuria (94.4%). The most infrequently taught topics were male urinary incontinence (59.4%), male infertility (52.4%) and erectile dysfunction (43.8%). Male and female catheterisation on patients as undergraduates was performed by 92.1% and 73.0% of FY1 doctors respectively, and 16.9% had considered a career in urology. Theory based teaching was mainly prevalent in the early years of medical school, with clinical skills teaching, and clinical placements in the later years of medical school. 20.1% of FY1 doctors reported no undergraduate clinical attachment in urology. CONCLUSION: LEARN is the largest ever evaluation of undergraduate urology teaching. In the UK, teaching seemed satisfactory as evaluated by the BAUS undergraduate syllabus. However, many students report having no clinical attachments in Urology and some newly qualified doctors report never having inserted a catheter, which is a GMC mandated requirement. We recommend a greater emphasis on undergraduate clinical exposure to urology and stricter adherence to GMC mandated procedures
Planning southern Iraq: placing the progressive theories of Max Lock in Um Qasr, Margil, and Basra in the context of Iraqi national development, 1954â1956
Between 1954 and 1956, the architect, educator, and planner, Max Lock (1909â1988) produced a trilogy of plans to modernize the historical city of Basra and create new areas at Margil and Um Qasr in the south of Iraq. The New Basrah Plan was heavily inspired by the works of Patrick Geddes and aligned with contemporaries such as Lewis Mumford, Lockâs planning was progressive in scope and looked to differ from the planning of post-war principles in Britain through his notions of âcivic surgeryâ. Contrary to this, his plans for Um Qasr and Margil focussed on infrastructure and the creation of more industrial areas not prioritizing people and place as highly as he did in the New Basrah Plan. Lockâs âCivic Surgeryâ offered an alternative to mainstream thought by attempting to create usable, humanistic spaces, which hampered by politics and legislation, resulted in the planâs shelving and were contradicted by his other worksâ philosophies. New retrospective analysis of his underappreciated career reveals the complexities of his planning which this article demonstrates through the âfailureâ of the New Basrah Plan and his plans at Um Qasr and Margil
Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.
Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field
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