Spatial Stit Tessellations: Distributional Results for I-Segments

In this paper we consider three-dimensional random tessellations that are stable under iteration (STIT tessellations). STIT tessellations arise as a result of subsequent cell division, which implies that their cells are not face-to-face. The edges of the cell-dividing polygons are the so-called I-segments of the tessellation. The main result is an explicit formula for the distribution of the number of vertices in the relative interior of the typical I-segment. In preparation for its proof, we obtain other distributional identities for the typical I-segment and the length-weighted typical I-segment, which provide new insight into the spatiotemporal construction process.

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Structure and function of neural networks in the retina

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102213 ◽

1988 ◽

Vol 46 ◽

pp. 26-27

Author(s):

Peter Sterling

Keyword(s):

Ganglion Cells ◽

Three Dimensional ◽

Structure And Function ◽

Synaptic Connections ◽

Visual Axis ◽

One Dimensional ◽

Cat Retina ◽

Ultrathin Sections ◽

And Function ◽

Insight Into

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

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Young Adults’ Contextualization of Environmental and Sustainability Issues: A Critical Issue for Environmental Education Intervention

Journal of Education in Black Sea Region ◽

10.31578/jebs.v3i1.116 ◽

2018 ◽

Vol 3 (1) ◽

Author(s):

Anthony KOLA-OLUSANYA

Keyword(s):

Young Adults ◽

Environmental Education ◽

Lived Experiences ◽

Critical Issue ◽

Decision Makers ◽

Research Approach ◽

Face To Face ◽

Research Questions ◽

Depth Interviews ◽

Insight Into

As soon as decision makers are expected to make differences towards sustainable future, young adults’ ability to make informed and sound decisions is considered essential towards securing our planet. This study provides an insight into young adults’ knowledge of key environment and sustainability issues. To answer the key research questions, data were obtained using a qualitative phenomenographic research approach and collected through 18 face-to-face in-depth interviews with research participants. The findings of this study suggest that young adults lived experiences that play a huge role in their level of awareness of topical environmental and sustainability issues critical to humanity’s future on earth.

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Faculty Opinions recommendation of Three-Dimensional Superresolution Imaging of the FtsZ Ring during Cell Division of the Cyanobacterium Prochlorococcus.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.732146604.793542893 ◽

2018 ◽

Author(s):

William Margolin

Keyword(s):

Cell Division ◽

Three Dimensional ◽

Superresolution Imaging ◽

Ftsz Ring

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The switching mechanisms of social network densification

Scientific Reports ◽

10.1038/s41598-021-82432-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Teruyoshi Kobayashi ◽

Mathieu Génois

Keyword(s):

Social Networks ◽

Social Network ◽

Social Context ◽

Social Interactions ◽

Regime Switching ◽

Face To Face ◽

The Social ◽

Switching Property ◽

Distinctive Type ◽

Insight Into

AbstractDensification and sparsification of social networks are attributed to two fundamental mechanisms: a change in the population in the system, and/or a change in the chances that people in the system are connected. In theory, each of these mechanisms generates a distinctive type of densification scaling, but in reality both types are generally mixed. Here, we develop a Bayesian statistical method to identify the extent to which each of these mechanisms is at play at a given point in time, taking the mixed densification scaling as input. We apply the method to networks of face-to-face interactions of individuals and reveal that the main mechanism that causes densification and sparsification occasionally switches, the frequency of which depending on the social context. The proposed method uncovers an inherent regime-switching property of network dynamics, which will provide a new insight into the mechanics behind evolving social interactions.

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Completely non-fused electron acceptor with 3D-interpenetrated crystalline structure enables efficient and stable organic solar cell

Nature Communications ◽

10.1038/s41467-021-25394-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Lijiao Ma ◽

Shaoqing Zhang ◽

Jincheng Zhu ◽

Jingwen Wang ◽

Junzhen Ren ◽

...

Keyword(s):

Organic Solar Cell ◽

Low Cost ◽

Three Dimensional ◽

Molecular Geometry ◽

Interpenetrating Network ◽

Fused Ring ◽

Molecule Design ◽

End Capping ◽

Conversion Efficiencies ◽

Insight Into

AbstractNon-fullerene acceptors (NFAs) based on non-fused conjugated structures have more potential to realize low-cost organic photovoltaic (OPV) cells. However, their power conversion efficiencies (PCEs) are much lower than those of the fused-ring NFAs. Herein, a new bithiophene-based non-fused core (TT-Pi) featuring good planarity as well as large steric hindrance was designed, based on which a completely non-fused NFA, A4T-16, was developed. The single-crystal result of A4T-16 reveals that a three-dimensional interpenetrating network can be formed due to the compact π–π stacking between the adjacent end-capping groups. A high PCE of 15.2% is achieved based on PBDB-TF:A4T-16, which is the highest value for the cells based on the non-fused NFAs. Notably, the device retains ~84% of its initial PCE after 1300 h under the simulated AM 1.5 G illumination (100 mW cm−2). Overall, this work provides insight into molecule design of the non-fused NFAs from the aspect of molecular geometry control.

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Fatigue-management strategies among women with endometriosis in South Africa: a qualitative study

South African Journal of Psychology ◽

10.1177/00812463211020173 ◽

2021 ◽

pp. 008124632110201

Author(s):

Zamafiso Nombulelo Sibande ◽

Rizwana Roomaney

Keyword(s):

South Africa ◽

South African ◽

Psychosocial Intervention ◽

Public Hospital ◽

Management Strategies ◽

Cognitive Strategies ◽

Secondary Symptom ◽

Face To Face ◽

Fatigue Management ◽

Insight Into

Fatigue is a common, secondary symptom of endometriosis that has not been qualitatively explored. We conducted individual, face-to-face interviews with 25 women in South Africa about their experiences of endometriosis-related fatigue. Participants were recruited at a public hospital in Cape Town and through several South African endometriosis organizations. Interviews were conducted in English and Afrikaans and ranged from 30 min to 1 hr 16 min in duration. All interviews were audio recorded and transcribed. Interviews were analyzed using thematic analysis. We found that both the experience of fatigue and fatigue-management strategies were highly personalized. Participants reported using a variety of cognitive strategies, such as planning, pacing, and pushing through their fatigue to reduce the levels of fatigue. Participants also employed physical strategies such as rest, dietary changes, using supplements, and exercise. We found that while participants often tried fatigue-management strategies suggested to them by others, they struggled to maintain these strategies even when they were successful. There are currently no interventions aimed at reducing endometriosis-related fatigue. The findings of this study provide insight into the management of fatigue in women with endometriosis and may be used to develop a psychosocial intervention for fatigue among women with the disease.

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The distribution of myosin II in Dictyostelium discoideum slug cells.

The Journal of Cell Biology ◽

10.1083/jcb.115.5.1267 ◽

1991 ◽

Vol 115 (5) ◽

pp. 1267-1274 ◽

Cited By ~ 12

Author(s):

S Eliott ◽

P H Vardy ◽

K L Williams

Keyword(s):

Cell Motility ◽

Dictyostelium Discoideum ◽

Immunofluorescence Microscopy ◽

Molecular Genetic ◽

Myosin Ii ◽

Three Dimensional ◽

Homogeneous Distribution ◽

Multicellular Development ◽

Insight Into

While the role of myosin II in muscle contraction has been well characterized, less is known about the role of myosin II in non-muscle cells. Recent molecular genetic experiments on Dictyostelium discoideum show that myosin II is necessary for cytokinesis and multicellular development. Here we use immunofluorescence microscopy with monoclonal and polyclonal antimyosin antibodies to visualize myosin II in cells of the multicellular D. discoideum slug. A subpopulation of peripheral and anterior cells label brightly with antimyosin II antibodies, and many of these cells display a polarized intracellular distribution of myosin II. Other cells in the slug label less brightly and their cytoplasm displays a more homogeneous distribution of myosin II. These results provide insight into cell motility within a three-dimensional tissue and they are discussed in relation to the possible roles of myosin II in multicellular development.

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Second Life as a research environment: avatar-based focus groups (AFG)

Qualitative Market Research An International Journal ◽

10.1108/qmr-08-2015-0070 ◽

2016 ◽

Vol 19 (1) ◽

pp. 101-114 ◽

Cited By ~ 4

Author(s):

Eman Gadalla ◽

Ibrahim Abosag ◽

Kathy Keeling

Keyword(s):

Focus Groups ◽

Data Quality ◽

Virtual Worlds ◽

Second Life ◽

Three Dimensional ◽

Marketing Research ◽

Two Phase ◽

Content Type ◽

Face To Face ◽

Advantages And Disadvantages

Purpose – This study aims to examine the nature and the potential use of avatar-based focus groups (AFGs) (i.e. focus groups conducted in three-dimensional [3D] virtual worlds [VWs]) as compared to face-to-face and online focus groups (OFGs), motivated by the ability of VWs to stimulate the realism of physical places. Over the past decade, there has been a rapid increase in using 3D VWs as a research tool. Design/methodology/approach – Using a two-phase reflective approach, data were collected first by using traditional face-to-face focus groups, followed by AFGs. In Phase 2, an online, semi-structured survey provided comparison data and experiences in AFGs, two-dimensional OFGs and traditional face-to-face focus groups. Findings – The findings identify the advantages and disadvantages of AFGs for marketing research. There is no evident difference in data quality between the results of AFGs and face-to-face focus groups. AFG compensates for some of the serious limitations associated with OFGs. Practical implications – The paper reflects on three issues, data quality, conduct of AFGs (including the moderator reflection) and participant experience, that together inform one’s understanding of the characteristics, advantages and limitations of AFG. Originality/value – This is the first paper to compare between AFGs, traditional face-to-face focus groups and OFGs. AFG holds many advantages over OFGs and even, sometimes, over face-to-face focus groups, providing a suitable environment for researchers to collect data.

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