115 research outputs found
Demonstration of a Thermally Coupled Row-Column SNSPD Imaging Array
While single-pixel superconducting nanowire single photon detectors (SNSPDs) have demonstrated remarkable efficiency and timing performance from the UV to near-IR, scaling these devices to large imaging arrays remains challenging. Here, we propose a new SNSPD multiplexing system using thermal coupling and detection correlations between two photosensitive layers of an array. Using this architecture with the channels of one layer oriented in rows and the second layer in columns, we demonstrate imaging capability in 16-pixel arrays with accurate spot tracking at the few-photon level. We also explore the performance trade-offs of orienting the top layer nanowires parallel and perpendicular to the bottom layer. The thermally coupled row-column scheme is readily able to scale to the kilopixel size with existing readout systems and, when combined with other multiplexing architectures, has the potential to enable megapixel scale SNSPD imaging arrays
Single-cell transcriptomic analysis of bloodstream Trypanosoma brucei reconstructs cell cycle progression and developmental quorum sensing
Developmental steps in the trypanosome life-cycle involve transition between replicative and non-replicative forms specialised for survival in, and transmission between, mammalian and tsetse fly hosts. Here, using oligopeptide-induced differentiation in vitro, we model the progressive development of replicative ‘slender’ to transmissible ‘stumpy’ bloodstream form Trypanosoma brucei and capture the transcriptomes of 8,599 parasites using single cell transcriptomics (scRNA-seq). Using this framework, we detail the relative order of biological events during asynchronous development, profile dynamic gene expression patterns and identify putative regulators. We additionally map the cell cycle of proliferating parasites and position stumpy cell-cycle exit at early G1 before progression to a distinct G0 state. A null mutant for one transiently elevated developmental regulator, ZC3H20 is further analysed by scRNA-seq, identifying its point of failure in the developmental atlas. This approach provides a paradigm for the dissection of differentiation events in parasites, relevant to diverse transitions in pathogen biology
Application of single cell transcriptomics to kinetoplastid research
Kinetoplastid parasites are responsible for both human and animal diseases across the globe where they have a great impact on health and economic well-being. Many species and life cycle stages are difficult to study due to limitations in isolation and culture, as well as to their existence as heterogeneous populations in hosts and vectors. Single-cell transcriptomics (scRNA-seq) has the capacity to overcome many of these difficulties, and can be leveraged to disentangle heterogeneous populations, highlight genes crucial for propagation through the life cycle, and enable detailed analysis of host–parasite interactions. Here, we provide a review of studies that have applied scRNA-seq to protozoan parasites so far. In addition, we provide an overview of sample preparation and technology choice considerations when planning scRNA-seq experiments, as well as challenges faced when analysing the large amounts of data generated. Finally, we highlight areas of kinetoplastid research that could benefit from scRNA-seq technologies
On Free-Electron Laser Growing Modes and their Bandwidth
Free-electron lasers play an increasing role in science, from generating
unique femtosecond X- ray pulses for single short recording of the protein
structures to amplifying feeble interactions in advanced cooling systems for
high-energy hadron colliders. While modern Free-electron laser codes can
describe their amplification mechanism, a deep analytical understanding of the
mechanism is of extreme importance for a number of applications. Mode
competition, their growth rates and amplification bandwidth are among the most
important parameters of a free-electron laser. A dispersion relation, which
defines these important characteristics, can be solved analytically only for a
very few simple cases. In this letter we show that for a typical bell-shape
energy distribution in electron beam there is no more that one growing mode. We
also derive an analytical expression which determines the bandwidth of the
free-electron laser.Comment: 4 pages, submitted to PR
Advancing the Provision of Pain Education and Learning (APPEAL) study
Objectives Unrelieved pain is a substantial public health concern
necessitating improvements in medical education. The Advancing the Provision
of Pain Education and Learning (APPEAL) study aimed to determine current
levels and methods of undergraduate pain medicine education in Europe. Design
and methods Using a cross-sectional design, publicly available curriculum
information was sought from all medical schools in 15 representative European
countries in 2012–2013. Descriptive analyses were performed on: the provision
of pain teaching in dedicated pain modules, other modules or within the
broader curriculum; whether pain teaching was compulsory or elective; the
number of hours/credits spent teaching pain; pain topics; and teaching and
assessment methods. Results Curriculum elements were publicly available from
242 of 249 identified schools (97%). In 55% (133/242) of schools, pain was
taught only within compulsory non-pain-specific modules. The next most common
approaches were for pain teaching to be provided wholly or in part via a
dedicated pain module (74/242; 31%) or via a vertical or integrated approach
to teaching through the broader curriculum, rather than within any specific
module (17/242; 7%). The curricula of 17/242 schools (7%) showed no evidence
of any pain teaching. Dedicated pain modules were most common in France (27/31
schools; 87%). Excluding France, only 22% (47/211 schools) provided a
dedicated pain module and in only 9% (18/211) was this compulsory. Overall,
the median number of hours spent teaching pain was 12.0 (range 4–56.0 h; IQR:
12.0) for compulsory dedicated pain modules and 9.0 (range 1.0–60.0 h; IQR:
10.5) for other compulsory (non-pain specific) modules. Pain medicine was
principally taught in classrooms and assessed by conventional examinations.
There was substantial international variation throughout. Conclusions
Documented pain teaching in many European medical schools falls far short of
what might be expected given the prevalence and public health burden of pain
Paving the Way:Contributions of Big Data to Apicomplexan and Kinetoplastid Research
In the age of big data an important question is how to ensure we make the most out of the resources we generate. In this review, we discuss the major methods used in Apicomplexan and Kinetoplastid research to produce big datasets and advance our understanding of Plasmodium, Toxoplasma, Cryptosporidium, Trypanosoma and Leishmania biology. We debate the benefits and limitations of the current technologies, and propose future advancements that may be key to improving our use of these techniques. Finally, we consider the difficulties the field faces when trying to make the most of the abundance of data that has already been, and will continue to be, generated
Demonstration of a Thermally Coupled Row-Column SNSPD Imaging Array
While single-pixel superconducting nanowire single photon detectors (SNSPDs) have demonstrated remarkable efficiency and timing performance from the UV to near-IR, scaling these devices to large imaging arrays remains challenging. Here, we propose a new SNSPD multiplexing system using thermal coupling and detection correlations between two photosensitive layers of an array. Using this architecture with the channels of one layer oriented in rows and the second layer in columns, we demonstrate imaging capability in 16-pixel arrays with accurate spot tracking at the few-photon level. We also explore the performance trade-offs of orienting the top layer nanowires parallel and perpendicular to the bottom layer. The thermally coupled row-column scheme is readily able to scale to the kilopixel size with existing readout systems and, when combined with other multiplexing architectures, has the potential to enable megapixel scale SNSPD imaging arrays
An occupational perspective of the lived experience of familial dementia caregivers : a thematic review of qualitative literature
Dementia caregiving is thought to have a negative impact on health and wellbeing. This critical review of qualitative literature explored the lived experience of familial dementia caregivers from an occupational therapy perspective. The method was informed by systematic review and qualitative research methodologies and was structured within the occupational dimensions framework of doing-being-becoming-belonging. A comprehensive search of major databases was undertaken which identified 484 studies on the topic; 14 met the inclusion criteria and were included in the review. Ten themes emerged within the doing-being-becoming-belonging framework from the analysis of the studies. The occupational participation of caregivers is conveyed within the ‘doing’ domain. Ways in which caregiving impacts upon opportunities for self-nurture are presented within the ‘being’ domain. The ‘becoming’ domain elucidates ways in which caregivers redefine themselves, their values and their priorities through their caregiving role. The ‘belonging’ domain depicts ways in which caregivers’ connections with their care recipient and others are shaped over time. Practice implications for health and social care practitioners who work with familial dementia caregivers are presented in light of the findings
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