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Webb JA, Farrow E, Cain B, Yuan Z, Yarawsky AE, Schoch E, Gagliani EK, Herr AB, Gebelein B, Kovall RA. Cooperative Gsx2-DNA Binding Requires DNA Bending and a Novel Gsx2 Homeodomain Interface. bioRxiv 2023:2023.12.08.570805. [PMID: 38106145 PMCID: PMC10723402 DOI: 10.1101/2023.12.08.570805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
The conserved Gsx homeodomain (HD) transcription factors specify neural cell fates in animals from flies to mammals. Like many HD proteins, Gsx factors bind A/T-rich DNA sequences prompting the question - how do HD factors that bind similar DNA sequences in vitro regulate specific target genes in vivo? Prior studies revealed that Gsx factors bind DNA both as a monomer on individual A/T-rich sites and as a cooperative homodimer to two sites spaced precisely seven base pairs apart. However, the mechanistic basis for Gsx DNA binding and cooperativity are poorly understood. Here, we used biochemical, biophysical, structural, and modeling approaches to (1) show that Gsx factors are monomers in solution and require DNA for cooperative complex formation; (2) define the affinity and thermodynamic binding parameters of Gsx2/DNA interactions; (3) solve a high-resolution monomer/DNA structure that reveals Gsx2 induces a 20° bend in DNA; (4) identify a Gsx2 protein-protein interface required for cooperative DNA binding; and (5) determine that flexible spacer DNA sequences enhance Gsx2 cooperativity on dimer sites. Altogether, our results provide a mechanistic basis for understanding the protein and DNA structural determinants that underlie cooperative DNA binding by Gsx factors, thereby providing a deeper understanding of HD specificity.
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Affiliation(s)
- Jordan A. Webb
- Department of Molecular and Cellular Biosciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Edward Farrow
- Graduate Program in Molecular and Developmental Biology, Cincinnati Children’s Hospital Research Foundation, Cincinnati, OH 45229, USA
- Medical-Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Brittany Cain
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Ave, MLC 7007, Cincinnati, OH 45229, USA
| | - Zhenyu Yuan
- Department of Molecular and Cellular Biosciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Alexander E. Yarawsky
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, 3333, Burnet Ave, Cincinnati, OH 45229, USA
| | - Emma Schoch
- Department of Medical Education, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Ellen K. Gagliani
- Department of Chemistry, Xavier University, Cincinnati, OH 45207, USA
| | - Andrew B. Herr
- Division of Immunobiology, Cincinnati Children’s Hospital Medical Center, 3333, Burnet Ave, Cincinnati, OH 45229, USA
| | - Brian Gebelein
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Ave, MLC 7007, Cincinnati, OH 45229, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Rhett A. Kovall
- Department of Molecular and Cellular Biosciences, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
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2
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Deva M, Osborne J, McGlynn A, Soars L, Loghdey S, Beath K, Gonski P, Dwyer P, Vasudeva N, Joshi P, Deva A. Disease Focused Integrated Care - a New Model of Healthcare Delivery for the Treatment of Skin Cancer. Int J Integr Care 2023; 23:12. [PMID: 37151779 PMCID: PMC10162353 DOI: 10.5334/ijic.7009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 04/21/2023] [Indexed: 05/09/2023] Open
Abstract
Introduction As the most common cancer in Australia, skin cancer generates a considerable health burden. This study outlines the establishment of a new model of integrated care for the diagnosis and management of skin cancer. Methods A new model of integrated care was established to provide access to all aspects of skin cancer management. General practitioners (GPs) were upskilled through hands-on training and a 6-month skin cancer education program and partnered with specialist Dermatologists and Plastic Surgeons co-located in the same clinic. Data including median wait times between the initial consultation and treatment were prospectively collected and compared patients seen through the integrated pathway to patients referred from their primary GP to specialist Dermatologists and Plastic Surgeons directly (non-integrated pathway). The percentage of patients needing co-consultation with a specialist in the integrated pathway was also measured over time. Results A total of 25341 patients were seen from the commencement of the clinic in August 2015 to June 2021. In 2017 and 2018 the median wait time to be treated was 7 days for the integrated model compared to 54 days (2017) and 46 days (2018) for non-integrated care (p < 0.0001). The percentage of GPs requesting specialist co-consultations for assessment of skin cancer fell from 98% in 2015, to 5.6% in 2021. Histopathology shows that 66% of lesions excised by GPs in this model were malignant or pre-malignant. Conclusions This study firstly shows a significant reduction in time to treatment in an integrated skin cancer model over traditional models of health. Secondly it demonstrates GP upskilling over time in the integrated program. Integrating GP and specialist medical practitioners in the treatment of skin cancer offers potential for more efficient, accessible, and affordable care. This cooperative, co-located model may provide a template for the integrating the management of other conditions.
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Affiliation(s)
- Maya Deva
- Integrated specialist healthcare education and research foundation, Australia
| | - Julie Osborne
- South Eastern Sydney Local Health District, Australia
| | - Anna McGlynn
- South Eastern Sydney Local Health District, Australia
| | - Linda Soars
- New South Wales Agency for Clinical Innovation, Australia
| | - Saleem Loghdey
- Integrated specialist healthcare education and research foundation, Australia
| | - Kenneth Beath
- School of Mathematical and Physical Sciences, Macquarie University, Australia
| | - Peter Gonski
- Integrated specialist healthcare education and research foundation, Australia
| | - Phil Dwyer
- Integrated specialist healthcare education and research foundation, Australia
| | - Nicholas Vasudeva
- Integrated specialist healthcare education and research foundation, Australia
| | - Preeti Joshi
- Integrated specialist healthcare education and research foundation, Australia
| | - Anand Deva
- Integrated specialist healthcare education and research foundation, Australia
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3
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Redondo-Rodríguez C, Becerra-Mejías JA, Gil-Fernández G, Rodríguez-Velasco FJ. Influence of Gamification and Cooperative Work in Peer, Mixed and Interdisciplinary Teams on Emotional Intelligence, Learning Strategies and Life Goals That Motivate University Students to Study. Int J Environ Res Public Health 2022; 20:547. [PMID: 36612869 PMCID: PMC9820013 DOI: 10.3390/ijerph20010547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/21/2022] [Accepted: 12/26/2022] [Indexed: 06/17/2023]
Abstract
It is necessary to motivate university students to reduce the dropout rate in Spain, and to look for strategies that help university students acquire professional competencies; this is where gamification can be useful. The purpose of the study was to evaluate the influence of a learning methodology based on gamification and cooperative work in peers, and in mixed and interdisciplinary teams on the emotional intelligence, learning strategies, and life goals that motivate university students to learn. The sample consisted of 102 students who took a subject with a gamification-based methodology, through the Mechanics-Dynamics-Aesthetics model, in a cooperative way. The Self-Perception Scale of Personal Academic Motivation and the Trait Meta Mood Scale 24 were used. The results of the study showed an increase in learning strategies and life goals that motivated university students to study, as well as increases in emotional clarity and significantly in emotional repair. It was concluded that gamification is a positive tool for its ability to increase emotional intelligence, life goals, and learning strategies in university students' motivation to learn.
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Affiliation(s)
- Celia Redondo-Rodríguez
- Department of Psychology and Anthropology, Teacher Training College, University of Extremadura, Av. de la Universidad, s/n, 10071 Cáceres, Spain
| | - José Alberto Becerra-Mejías
- Department of Nursing, University Center of Plasencia, University of Extremadura, C. Virgen del Puerto No. 2, 10600 Plasencia, Spain
| | - Guadalupe Gil-Fernández
- Department of Nursing, Faculty of Medicine and Health Sciences, University of Extremadura, Av. Elvas, s/n, 06006 Badajoz, Spain
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4
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Du J, Estrella M, Solorio-Kirpichyan K, Jeffrey PD, Korennykh A. Structure of human NADK2 reveals atypical assembly and regulation of NAD kinases from animal mitochondria. Proc Natl Acad Sci U S A 2022; 119:e2200923119. [PMID: 35733246 PMCID: PMC9245612 DOI: 10.1073/pnas.2200923119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 04/18/2022] [Indexed: 11/18/2022] Open
Abstract
All kingdoms of life produce essential nicotinamide dinucleotide NADP(H) using NAD kinases (NADKs). A panel of published NADK structures from bacteria, eukaryotic cytosol, and yeast mitochondria revealed similar tetrameric enzymes. Here, we present the 2.8-Å structure of the human mitochondrial kinase NADK2 with a bound substrate, which is an exception to this uniformity, diverging both structurally and biochemically from NADKs. We show that NADK2 harbors a unique tetramer disruptor/dimerization element, which is conserved in mitochondrial kinases of animals (EMKA) and absent from other NADKs. EMKA stabilizes the NADK2 dimer but prevents further NADK2 oligomerization by blocking the tetramerization interface. This structural change bears functional consequences and alters the activation mechanism of the enzyme. Whereas tetrameric NADKs undergo cooperative activation via oligomerization, NADK2 is a constitutively active noncooperative dimer. Thus, our data point to a unique regulation of NADP(H) synthesis in animal mitochondria achieved via structural adaptation of the NADK2 kinase.
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Affiliation(s)
- Jin Du
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
| | - Michael Estrella
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
| | | | - Philip D. Jeffrey
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
| | - Alexei Korennykh
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
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5
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Webb CT, Yang W, Riley BT, Hayes BK, Sivaraman KK, Malcolm TR, Harrop S, Atkinson SC, Kass I, Buckle AM, Drinkwater N, McGowan S. A metal ion-dependent conformational switch modulates activity of the Plasmodium M17 aminopeptidase. J Biol Chem 2022; 298:102119. [PMID: 35691342 PMCID: PMC9270245 DOI: 10.1016/j.jbc.2022.102119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 06/04/2022] [Accepted: 06/07/2022] [Indexed: 11/12/2022] Open
Abstract
The metal-dependent M17 aminopeptidases are conserved throughout all kingdoms of life. This large enzyme family is characterized by a conserved binuclear metal center and a distinctive homohexameric arrangement. Recently, we showed that hexamer formation in Plasmodium M17 aminopeptidases was controlled by the metal ion environment, although the functional necessity for hexamer formation is still unclear. To further understand the mechanistic role of the hexameric assembly, here we undertook an investigation of the structure and dynamics of the M17 aminopeptidase from Plasmodium falciparum, PfA-M17. We describe a novel structure of PfA-M17, which shows that the active sites of each trimer are linked by a dynamic loop, and loop movement is coupled with a drastic rearrangement of the binuclear metal center and substrate-binding pocket, rendering the protein inactive. Molecular dynamics simulations and biochemical analyses of PfA-M17 variants demonstrated that this rearrangement is inherent to PfA-M17, and that the transition between the active and inactive states is metal dependent and part of a dynamic regulatory mechanism. Key to the mechanism is a remodeling of the binuclear metal center, which occurs in response to a signal from the neighboring active site and serves to moderate the rate of proteolysis under different environmental conditions. In conclusion, this work identifies a precise mechanism by which oligomerization contributes to PfA-M17 function. Furthermore, it describes a novel role for metal cofactors in the regulation of enzymes, with implications for the wide range of metalloenzymes that operate via a two-metal ion catalytic center, including DNA processing enzymes and metalloproteases.
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Affiliation(s)
- Chaille T Webb
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton Melbourne, VIC 3800, Australia
| | - Wei Yang
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton Melbourne, VIC 3800, Australia; Current address Warshel Institute for Computational Biology, The Chinese University of Hong Kong, Shenzhen, 518172, China
| | - Blake T Riley
- Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton Melbourne, VIC 3800, Australia
| | - Brooke K Hayes
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton Melbourne, VIC 3800, Australia
| | - Komagal Kannan Sivaraman
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton Melbourne, VIC 3800, Australia
| | - Tess R Malcolm
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton Melbourne, VIC 3800, Australia
| | - Stephen Harrop
- Australian Synchrotron. 800 Blackburn Road, Clayton, VIC, 3168, Australia
| | - Sarah C Atkinson
- Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton Melbourne, VIC 3800, Australia
| | - Itamar Kass
- Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton Melbourne, VIC 3800, Australia; Victorian Life Sciences Computation Center, Monash University, Clayton 3800, Victoria, Australia; Current address InterX LTD, Ramat-Gan, Israel
| | - Ashley M Buckle
- Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton Melbourne, VIC 3800, Australia
| | - Nyssa Drinkwater
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton Melbourne, VIC 3800, Australia
| | - Sheena McGowan
- Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton Melbourne, VIC 3800, Australia.
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6
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Hughes SM, Hendricks MP, Mullaugh KM, Anderson ME, Bentley AK, Clar JG, Daly CA, Ellison MD, Feng ZV, Gonzalez-Pech NI, Hamachi LS, Heinecke CL, Keene JD, Maley AM, Munro AM, Njoki PN, Olshansky JH, Plass KE, Riley KR, Sonntag MD, St. Angelo SK, Thompson LB, Tollefson EJ, Toote LE, Wheeler KE. The Primarily Undergraduate Nanomaterials Cooperative: A New Model for Supporting Collaborative Research at Small Institutions on a National Scale. ACS Nanosci Au 2021; 1:6-14. [PMID: 37102118 PMCID: PMC10114623 DOI: 10.1021/acsnanoscienceau.1c00020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
The Primarily Undergraduate Nanomaterials Cooperative (PUNC) is an organization for research-active faculty studying nanomaterials at Primarily Undergraduate Institutions (PUIs), where undergraduate teaching and research go hand-in-hand. In this perspective, we outline the differences in maintaining an active research group at a PUI compared to an R1 institution. We also discuss the work of PUNC, which focuses on community building, instrument sharing, and facilitating new collaborations. Currently consisting of 37 members from across the United States, PUNC has created an online community consisting of its Web site (nanocooperative.org), a weekly online summer group meeting program for faculty and students, and a Discord server for informal conversations. Additionally, in-person symposia at ACS conferences and PUNC-specific conferences are planned for the future. It is our hope that in the years to come PUNC will be seen as a model organization for community building and research support at primarily undergraduate institutions.
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Affiliation(s)
- Steven M. Hughes
- Department
of Chemistry, Roanoke College, 221 College Lane, Salem, Virginia 24153, United States
| | - Mark P. Hendricks
- Department
of Chemistry, Whitman College, 345 Boyer Avenue, Walla Walla, Washington 99362, United States
| | - Katherine M. Mullaugh
- Department
of Chemistry and Biochemistry, College of
Charleston, 66 George Street, Charleston, South Carolina 29424, United States
| | - Mary E. Anderson
- Department
of Chemistry, Furman University, 3300 Poinsett Highway, Greenville, South Carolina 29613, United States
| | - Anne K. Bentley
- Department
of Chemistry, Lewis & Clark College, 615 S Palatine Hill Rd, Portland, Oregon 97219, United States
| | - Justin G. Clar
- Department
of Chemistry, Elon University, 2625 Campus Box, Elon, North Carolina 27244, United States
| | - Clyde A. Daly
- Department
of Chemistry, Haverford College, 370 Lancaster Avenue, Haverford, Pennsylvania 19041, United States
| | - Mark D. Ellison
- Department
of Chemistry, Ursinus College, P.O. Box 1000, Collegeville, Pennsylvania 19426, United States
| | - Z. Vivian Feng
- Department
of Chemistry, Augsburg University, 2211 Riverside Avenue, Minneapolis, Minnesota 55454, United States
| | - Natalia I. Gonzalez-Pech
- Department
of Chemistry, Hope College, 35 East 12th Street, Holland, Michigan 49423, United States
| | - Leslie S. Hamachi
- Department
of Chemistry & Biochemistry, California
Polytechnic State University, 1 Grand Avenue, San Luis Obispo, California 93401, United States
| | - Christine L. Heinecke
- Department
of Chemistry & Biochemistry, Loyola
University New Orleans, 6363 St. Charles Avenue, New Orleans, Louisiana 70118, United States
| | - Joseph D. Keene
- Department
of Chemistry, Mercer University, 1501 Mercer University Drive, Macon, Georgia 31207, United States
| | - Adam M. Maley
- Mund-Lagowski
Department of Chemistry and Biochemistry, Bradley University, 1501 W Bradley Avenue, Peoria, Illinois 61625, United
States
| | - Andrea M. Munro
- Department
of Chemistry, Pacific Lutheran University, 12180 Park Avenue, Tacoma, Washington 98447, United States
| | - Peter N. Njoki
- Department
of Chemistry & Biochemistry, Hampton
University, 130 William R. Harvey Way, Hampton, Virginia 23668, United
States
| | - Jacob H. Olshansky
- Department
of Chemistry, Amherst College, 25 East Drive, Amherst, Massachusetts 01002, United States
| | - Katherine E. Plass
- Department
of Chemistry, Franklin & Marshall College, P.O. Box 3003, Lancaster, Pennsylvania 17601, United States
| | - Kathryn R. Riley
- Department
of Chemistry & Biochemistry, Swarthmore
College, 500 College Avenue, Swarthmore, Pennsylvania 19081, United States
| | - Matthew D. Sonntag
- Department
of Chemistry & Biochemistry, Albright
College, P.O. Box 15234, Reading, Pennsylvania 19612, United States
| | - Sarah K. St. Angelo
- Department
of Chemistry, Dickinson College, P.O. Box 1773, Carlisle, Pennsylvania 17013, United States
| | - Lucas B. Thompson
- Department
of Chemistry, Gettysburg College, 300 North Washington Street, Gettysburg, Pennsylvania 17325, United States
| | - Emily J. Tollefson
- Department
of Chemistry, University of Puget Sound, 1500 N Warner Street, Tacoma, Washington 98416, United States
| | - Lauren E. Toote
- Department
of Chemistry & Biochemistry, Elizabethtown
College, 1 Alpha Drive, Elizabethtown, Pennsylvania 17022, United States
| | - Korin E. Wheeler
- Department
of Chemistry & Biochemistry, Santa Clara
University, 500 El Camino Real, Santa Clara, California 95053, United States
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7
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Lv D, Li J, Ye S. The Assembly Switch Mechanism of FtsZ Filament Revealed by All-Atom Molecular Dynamics Simulations and Coarse-Grained Models. Front Microbiol 2021; 12:639883. [PMID: 33859629 PMCID: PMC8042166 DOI: 10.3389/fmicb.2021.639883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 03/05/2021] [Indexed: 01/14/2023] Open
Abstract
Bacterial cytoskeletal protein FtsZ binds and hydrolyzes GTP, and assembles into dynamic filaments that are essential for cell division. Here, we used a multi-scale computational strategy that combined all-atom molecular dynamics (MD) simulations and coarse-grained models to reveal the conformational dynamics of assembled FtsZ. We found that the top end of a filament is highly dynamic and can undergo T-to-R transitions in both GTP- and GDP-bound states. We observed several subcategories of nucleation related dimer species, which leading to a feasible nucleation pathway. In addition, we observed that FtsZ filament exhibits noticeable amounts of twisting, indicating a substantial helicity of the FtsZ filament. These results agree with the previously models and experimental data. Anisotropy network model (ANM) analysis revealed a polymerization enhanced assembly cooperativity, and indicated that the cooperative motions in FtsZ are encoded in the structure. Taken together, our study provides a molecular-level understanding of the diversity of the structural states of FtsZ and the relationships among polymerization, hydrolysis, and cooperative assembly, which should shed new light on the molecular basis of FtsZ’s cooperativity.
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Affiliation(s)
- Dashuai Lv
- Life Sciences Institute, Zhejiang University, Hangzhou, China
| | - Jingyuan Li
- Zhejiang Province Key Laboratory of Quantum Technology and Device, Department of Physics, Institute of Quantitative Biology, Hangzhou, China
| | - Sheng Ye
- Life Sciences Institute, Zhejiang University, Hangzhou, China.,Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, School of Life Sciences, Tianjin University, Tianjin, China
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8
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Aranas LL, Khanam R, Rahman MM, Nghiem S. Combining Microfinance and Health in Reducing Poverty-Driven Healthcare Costs: Evidence From the Philippines. Front Public Health 2020; 8:583455. [PMID: 33134241 PMCID: PMC7578378 DOI: 10.3389/fpubh.2020.583455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 08/31/2020] [Indexed: 11/13/2022] Open
Abstract
The role of microfinance in alleviating poverty and poor health is significant. Its health programs have been shown to improve healthcare utilization and strengthen a healthcare system. In the Philippines, microfinance's widespread presence is seen as instrumental in achieving the objectives of Healthy Philippines 2022, particularly in reducing poverty-driven healthcare costs. However, little is known on how microfinance can reduce the cost of healthcare services and treatment. Also, few studies that consider the practice of integrated microfinance and health programs in the Philippines have been seen. Secondary data was used to explore the structure and function of microfinance and health initiatives and their influence in mitigating healthcare costs. A review criterion was developed to examine the data using the three key elements identified in Ruducha and Jadhav's framework: organisational arrangement, health products and health outcomes. Findings revealed that most health initiatives are delivered through partnerships and collaboration, could favour a reduction in healthcare costs and protection from out-of-pocket health expenditure. They are designed to operate in three structures-subsidised or outreach, microinsurance and health loans, and patronage refunds. The cooperative's business venture providing pharmaceuticals facilitated access to affordable medicine and offered its members financial viability. Health loans and microinsurance also offered healthcare cost reductions; however, uptakes are low. The study found no data to assess the output of the completed health initiatives. More studies that will evaluate the integrated MFI health initiatives are recommended to further identify gaps, outcomes, or impacts of the program.
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Affiliation(s)
- Lolita L. Aranas
- Graduate Research Studies, University of Southern Queensland, Toowoomba, QLD, Australia
- Graduate Research Studies, Jose Rizal University, National Capital Region, Mandaluyong, Philippines
| | - Rasheda Khanam
- School of Commerce, Center for Health Research, University of Southern Queensland, Toowoomba, QLD, Australia
| | - Mohammad Mafizur Rahman
- School of Commerce, Center for Health Research, University of Southern Queensland, Toowoomba, QLD, Australia
| | - Son Nghiem
- Centre for Applied Health Economics, Griffith University, Brisbane, QLD, Australia
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9
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Agrawal DC, Yadav A, Khan MA, Kundu S, Kayastha AM. Denaturant Induced Equilibrium Unfolding and Conformational Transitional Studies of Germinated Fenugreek β-Amylase Revealed Molten Globule like State at Low pH. Protein Pept Lett 2020; 27:1046-1057. [PMID: 32242773 DOI: 10.2174/0929866527666200403082721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/22/2020] [Accepted: 02/24/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND β-Amylase (EC 3.2.1.2) is a maltogenic enzyme, which releases β-maltose from the non-reducing end of the substrates. The enzyme plays important roles for the production of vaccine, maltiol and maltose rich syrups. Apart from these applications the enzyme protects cells from abiotic as well as oxidative damage. The enzyme is βwell characterized in βplants and microbes and crystal structures of β-amylases βhave been βobtained from sweet potato, soybean and Bacillus cereus. OBJECTIVE Find out correlation between structural and functional stability induced by change in pH, temperature and chaotropes. METHODS Activity, intrinsic fluorescence, extrinsic fluorescence, near- and far- ultraviolet circular dichroism spectroscopic measurements were performed. RESULTS Peaks about 208 nm and 222 nm obtained by near-ultraviolet circular dichroism correspond to α-helix whereas peak at 215 nm shows presence of β-sheet. At pH 2.0, absence of tertiary structures, exposed of hydrophobic regions and presence of substantial secondary structures, revealed the existence of molten globule like state. Temperature induced denaturation studies showed that the enzyme was stable up to 75 ºC and the process was found to be irreversible in nature. Chaotropes dependent equilibrium unfolding studies revealed that at low concentration of chaotropes, ellipticity and intrinsic fluorescence βintensity were βdecreased βwhereas βenzymatic activity remained unchanged, which revealed fenugreek β-amylase is multi-domains enzyme and catalytic βdomain βis more βstable compare to non-catalytic domain. Moreover, the transition was sigmoidal and non-coincidental. CONCLUSION Results indicate the probable existence of intermediate states that might perform significant role in physiological process and biotechnological applications.
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Affiliation(s)
- Dinesh Chand Agrawal
- School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Anjali Yadav
- School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Mohd Asim Khan
- Department of Biochemistry, University of Delhi South Campus, New Delhi 110021, India
| | - Suman Kundu
- Department of Biochemistry, University of Delhi South Campus, New Delhi 110021, India
| | - Arvind M Kayastha
- School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi 221005, India
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10
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Feng B, Shen D, Wang W, Deng Z, Lin L, Ren H, Wu A, Zou G, Liu L, Zhou YN. Cooperative Bilayer of Lattice-Disordered Nanoparticles as Room-Temperature Sinterable Nanoarchitecture for Device Integrations. ACS Appl Mater Interfaces 2019; 11:16972-16980. [PMID: 30945537 DOI: 10.1021/acsami.9b00307] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Decreasing the interconnecting temperature is essential for 3D and heterogeneous device integrations, which play indispensable roles in the coming era of "more than Moore". Although nanomaterials exhibit a decreased onset temperature for interconnecting, such an effect is always deeply impaired because of organic additives in practical integrations. Meanwhile, current organic-free integration strategies suffer from roughness and contaminants at the bonding interface. Herein, a novel bilayer nanoarchitecture simultaneously overcomes the drawbacks of organics and is highly tolerant to interfacial morphology, which exhibits universal applicability for device-level integrations at even room temperature, with the overall performance outperforming most counterparts reported. This nanoarchitecture features a loose nanoparticle layer with unprecedented deformability for interfacial gap-filling, and a compact one providing firm bonding with the component surface. The two distinct nanoparticle layers cooperatively enhance the interconnecting performance by 73-357%. Apart from the absence of organics, the internal abundant lattice disorders profoundly accelerate the interconnecting process, which is supported by experiments and molecular dynamics simulation. This nanoarchitecture is successfully demonstrated in diversified applications including paper-based light-emitting diodes, Cu-Cu micro-bonding, and SiC power modules. The strategy proposed here can open a new paradigm for device integrations and provide a fresh understanding on interconnecting mechanisms.
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Affiliation(s)
- Bin Feng
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Daozhi Shen
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Wengan Wang
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Zhongyang Deng
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Luchan Lin
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Hui Ren
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Aiping Wu
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Guisheng Zou
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Lei Liu
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
| | - Y Norman Zhou
- Department of Mechanical Engineering, State Key Laboratory of Tribology , Tsinghua University , Beijing 100084 , China
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Trujillo JC, Munguia R, Guerra E, Grau A. Cooperative Monocular-Based SLAM for Multi-UAV Systems in GPS-Denied Environments. Sensors (Basel) 2018; 18:s18051351. [PMID: 29701722 PMCID: PMC5981868 DOI: 10.3390/s18051351] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 04/03/2018] [Accepted: 04/19/2018] [Indexed: 11/16/2022]
Abstract
This work presents a cooperative monocular-based SLAM approach for multi-UAV systems that can operate in GPS-denied environments. The main contribution of the work is to show that, using visual information obtained from monocular cameras mounted onboard aerial vehicles flying in formation, the observability properties of the whole system are improved. This fact is especially notorious when compared with other related visual SLAM configurations. In order to improve the observability properties, some measurements of the relative distance between the UAVs are included in the system. These relative distances are also obtained from visual information. The proposed approach is theoretically validated by means of a nonlinear observability analysis. Furthermore, an extensive set of computer simulations is presented in order to validate the proposed approach. The numerical simulation results show that the proposed system is able to provide a good position and orientation estimation of the aerial vehicles flying in formation.
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Affiliation(s)
- Juan-Carlos Trujillo
- Department of Computer Science, CUCEI, University of Guadalajara, Guadalajara 44430, Mexico.
| | - Rodrigo Munguia
- Department of Computer Science, CUCEI, University of Guadalajara, Guadalajara 44430, Mexico.
| | - Edmundo Guerra
- Department of Automatic Control, Technical University of Catalonia UPC, 08034 Barcelona, Spain.
| | - Antoni Grau
- Department of Automatic Control, Technical University of Catalonia UPC, 08034 Barcelona, Spain.
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Cook TR, Gubiani R, Ryan PG, Muzaffar SB. Group foraging in Socotra cormorants: A biologging approach to the study of a complex behavior. Ecol Evol 2017; 7:2025-2038. [PMID: 28405270 PMCID: PMC5383476 DOI: 10.1002/ece3.2750] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 12/06/2016] [Accepted: 12/22/2016] [Indexed: 11/11/2022] Open
Abstract
Group foraging contradicts classic ecological theory because intraspecific competition normally increases with aggregation. Hence, there should be evolutionary benefits to group foraging. The study of group foraging in the field remains challenging however, because of the large number of individuals involved and the remoteness of the interactions to the observer. Biologging represents a cost-effective solution to these methodological issues. By deploying GPS and temperature-depth loggers on individuals over a period of several consecutive days, we investigated intraspecific foraging interactions in the Socotra cormorant Phalacrocorax nigrogularis, a threatened colonial seabird endemic to the Arabian Peninsula. In particular, we examined how closely birds from the same colony associated with each other spatially when they were at sea at the same time and the distance between foraging dives at different periods of the day. Results show that the position of different birds overlapped substantially, all birds targeting the same general foraging grounds throughout the day, likely following the same school of fish. There were as many as 44,500 birds within the foraging flock at sea at any time (50% of the colony), and flocking density was high, with distance between birds ranging from 8 to 1,380 m. Birds adopted a diving strategy maximizing time spent underwater relative to surface time, resulting in up to 72% of birds underwater in potential contact with prey at all times while foraging. Our data suggest that the benefits of group foraging outweigh the costs of intense aggregation in this seabird. Prey detection and information transmission are facilitated in large groups. Once discovered, shoaling prey are concentrated under the effect of the multitude. Fish school cohesiveness is then disorganized by continuous attacks of diving birds to facilitate prey capture. Decreasing population size could pose a risk to the persistence of threatened seabirds where group size is important for foraging success.
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Affiliation(s)
- Timothée R Cook
- Department of Evolutionary Ecology Evolutionary Ecophysiology Team Institute of Ecology and Environmental Sciences University Pierre et Marie Curie Paris France; FitzPatrick Institute of African Ornithology DST-NRF Centre of Excellence University of Cape Town Rondebosch South Africa
| | - Rob Gubiani
- Department of Biology United Arab Emirates University Al Ain United Arab Emirates
| | - Peter G Ryan
- FitzPatrick Institute of African Ornithology DST-NRF Centre of Excellence University of Cape Town Rondebosch South Africa
| | - Sabir B Muzaffar
- Department of Biology United Arab Emirates University Al Ain United Arab Emirates
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13
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de Ponte Müller F. Survey on Ranging Sensors and Cooperative Techniques for Relative Positioning of Vehicles. Sensors (Basel) 2017; 17:E271. [PMID: 28146129 DOI: 10.3390/s17020271] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 01/24/2017] [Indexed: 11/16/2022]
Abstract
Future driver assistance systems will rely on accurate, reliable and continuous knowledge on the position of other road participants, including pedestrians, bicycles and other vehicles. The usual approach to tackle this requirement is to use on-board ranging sensors inside the vehicle. Radar, laser scanners or vision-based systems are able to detect objects in their line-of-sight. In contrast to these non-cooperative ranging sensors, cooperative approaches follow a strategy in which other road participants actively support the estimation of the relative position. The limitations of on-board ranging sensors regarding their detection range and angle of view and the facility of blockage can be approached by using a cooperative approach based on vehicle-to-vehicle communication. The fusion of both, cooperative and non-cooperative strategies, seems to offer the largest benefits regarding accuracy, availability and robustness. This survey offers the reader a comprehensive review on different techniques for vehicle relative positioning. The reader will learn the important performance indicators when it comes to relative positioning of vehicles, the different technologies that are both commercially available and currently under research, their expected performance and their intrinsic limitations. Moreover, the latest research in the area of vision-based systems for vehicle detection, as well as the latest work on GNSS-based vehicle localization and vehicular communication for relative positioning of vehicles, are reviewed. The survey also includes the research work on the fusion of cooperative and non-cooperative approaches to increase the reliability and the availability.
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Abstract
A chiral NHC/Brønsted acid cooperative catalysis system has been developed for asymmetric annulation of functionalized benzaldehydes and activated ketones through dearomative generation of dienolate.
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Affiliation(s)
- Dian-Feng Chen
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Tomislav Rovis
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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15
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Abstract
Ubiquitin-like with PHD and RING Finger domains 1 (UHRF1) is an important nuclear protein that is mutated and aberrantly expressed in many tumors. The protein integrates different chromatin modifications and is essential for their maintenance throughout the cell cycle. Separate chromatin-binding modules of UHRF1 have been studied on a functional and structural level. The unmodified N-terminus of histone H3 is recognized by a PHD domain, while a TTD domain specifically interacts with histone H3 Lysine 9 trimethylation. A SRA region binds hemimethylatd DNA. Emerging evidence indicates that the modules of UHRF1 do not act independently of each other but establish complex modes of interaction with patterns of chromatin modifications. This multivalent readout is regulated by allosteric binding of phosphatidylinositol 5-phosphate to a region outside the PHD, TTD and SRA domains as well as by phosphorylation of one of the linker regions connecting these modules. Here, we summarize the current knowledge on UHRF1 chromatin interaction and introduce a novel model of conformational transitions of the protein that are directed by the flexible and highly charged linker regions. We propose that these are essential in setting up defined structural states of the protein where different domains or combinations thereof are available for binding chromatin modifications or are prevented from doing so. Lastly, we suggest that controlled tuning of intramolecular linker interactions by ligands and posttranslational modifications establishes a rational framework for comprehending UHRF1 regulation and putatively the working mode of other chromatin factors in different physiological contexts.
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Affiliation(s)
- Maria Tauber
- a Laboratory of Chromatin Biochemistry ; Max Planck Institute for Biophysical Chemistry ; Göttingen , Germany
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Enz S, Frosch DR. Effect of Collaborative vs. Noncollaborative Quizzes on Examination Scores in a Pharmaceutical Calculations Course. Am J Pharm Educ 2015; 79:66. [PMID: 26396275 PMCID: PMC4571041 DOI: 10.5688/ajpe79566] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 12/08/2014] [Indexed: 06/01/2023]
Abstract
OBJECTIVE To determine if midterm and final examination scores in a pharmaceutical calculations course differ among students who take weekly quizzes collaboratively, noncollaboratively, or half-collaboratively/half-noncollaboratively ("mixed"). METHODS One hundred twenty-three students enrolled in one of 4 laboratory sections: collaborative, noncollaborative, or mixed sections. Students working noncollaboratively completed a 15-minute quiz at the end of weekly laboratories. Students working collaboratively were randomly allocated into groups of 4 and worked independently for 5 minutes before working collaboratively for 10 minutes. Students in mixed sections worked collaboratively during one half of the semester and noncollaboratively during the other half of the semester in a crossover design to control for order effect. All students took midterm and final examinations independently. RESULTS Mean scores for a pretest did not significantly differ between the 4 laboratory sections at the study's onset. Multivariate analysis of variance (MANOVA) revealed a significant multivariate effect for the 9 laboratory quizzes in relation to group assignment. Mean scores on the midterm examination did not significantly differ between collaborative and noncollaborative groups. On the final examination, the two mixed groups significantly outperformed the collaborative group, but did not significantly differ from one another or from the noncollaborative group. CONCLUSION Peer collaboration improves quiz scores, is favorably perceived by students and enhances their course satisfaction, but does not improve subsequent performance on midterm and final examinations taken noncollaboratively.
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Affiliation(s)
- Stephanie Enz
- Butler University College of Pharmacy and Health Sciences, Indianapolis, Indiana
| | - Donald R Frosch
- Butler University College of Pharmacy and Health Sciences, Indianapolis, Indiana
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Abstract
INTRODUCTION This article is part of a Focus Theme of Methods of Information in Medicine on Health Record Banking. BACKGROUND Healthcare is often ineffective and costs are steadily rising. This is in a large part due to the inaccessibility of medical and health data stored in multiple silos. Furthermore, in most cases molecular differences between individuals that result in different susceptibilities to drugs and diseases as well as targeted interventions cannot be taken into account. Technological advances in genome sequencing and the interaction of 'omics' data with environmental data on one hand and mobile health on the other, promise to generate the longitudinal health data that will form the basis for a more personalized, precision medicine. OBJECTIVES For this new medicine to become a reality, however, millions of personal health data sets have to be aggregated. The value of such aggregated personal data has been recognized as a new asset class and many commercial entities are competing for this new asset (e.g. Google, Facebook, 23andMe, PatientsLikeMe). The primary source and beneficiary of personal health data is the individual. As a collective, society should be the beneficiary of both the economic and health value of these aggregated data and (health) information. METHODS We posit that empowering citizens by providing them with a platform to safely store, manage and share their health-related data will be a necessary element in the transformation towards a more effective and efficient precision medicine. Such health data platforms should be organized as cooperatives that are solely owned and controlled by their members and not by shareholders. Members determine which data they want to share for example with doctors or to contribute to research for the benefit of their health and that of society. Members will also decide how the revenues generated by granting third parties access to the anonymized data that they agreed to share, should be invested in research, information or education. RESULTS Currently no functional Health Data Cooperatives exist yet. The relative success of health data repositories such as 23andme and PatientsLikeMe indicates that citizens are willing to participate in research even if - and in contrast to the cooperative model - the commercial value of these data does not go back to the collective of users. CONCLUSIONS In the Health Data Cooperative model, the citizens with their data would take the center stage in the healthcare system and society would benefit from the health-related and financial benefits that aggregation of these data brings.
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Affiliation(s)
- E Hafen
- Ernst Hafen, Institute of Molecular Systems Biology, ETH Zurich, 8093 Zurich, Switzerland, E-mail:
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Abstract
To survive floods, fire ants link their bodies together to build waterproof rafts. Such rafts can be quite large, exceeding 100,000 individuals in size. In this study, we make two improvements on a previously reported model on the construction rate of rafts numbering between 3,000 and 10,000 individuals. That model was based upon experimental observations of randomly-directed linear ant trajectories atop the raft. Here, we report anomalous behavior of ants atop larger rafts of up to 23,000 ants. As rafts increase in size, the behavior of ants approaches diffusion, which is in closer alignment with other studies on the foraging and scouting patterns of ants. We incorporate this ant behavior into the model. Our modified model predicts more accurately the growth of large rafts. Our previous model also relied on an assumption of raft circularity. We show that this assumption is not necessary for large rafts, because it follows from the random directionality of the ant trajectories. Our predicted relationship between raft size and circularity closely fits experimental data.
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Affiliation(s)
- Nathan J. Mlot
- School of Mechanical Engineering; Georgia Institute of Technology; Atlanta, GA USA
| | - Craig Tovey
- School of Industrial Systems and Engineering; Georgia Institute of Technology; Atlanta, GA USA
| | - David L. Hu
- School of Mechanical Engineering; Georgia Institute of Technology; Atlanta, GA USA
- School of Biology; Georgia Institute of Technology; Atlanta, GA USA
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Bel A, Vicario JL, Seco-Granados G. Localization algorithm with on-line path loss estimation and node selection. Sensors (Basel) 2011; 11:6905-25. [PMID: 22163992 PMCID: PMC3231661 DOI: 10.3390/s110706905] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 06/17/2011] [Accepted: 06/21/2011] [Indexed: 11/25/2022]
Abstract
RSS-based localization is considered a low-complexity algorithm with respect to other range techniques such as TOA or AOA. The accuracy of RSS methods depends on the suitability of the propagation models used for the actual propagation conditions. In indoor environments, in particular, it is very difficult to obtain a good propagation model. For that reason, we present a cooperative localization algorithm that dynamically estimates the path loss exponent by using RSS measurements. Since the energy consumption is a key point in sensor networks, we propose a node selection mechanism to limit the number of neighbours of a given node that are used for positioning purposes. Moreover, the selection mechanism is also useful to discard bad links that could negatively affect the performance accuracy. As a result, we derive a practical solution tailored to the strict requirements of sensor networks in terms of complexity, size and cost. We present results based on both computer simulations and real experiments with the Crossbow MICA2 motes showing that the proposed scheme offers a good trade-off in terms of position accuracy and energy efficiency.
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Affiliation(s)
- Albert Bel
- Signal Processing for Communications and Navigation Group, Telecommunications and Systems Engineering Department, Universitat Autònoma de Barcelona, Edifici Q Campus de la UAB, Bellaterra (Cerdanyola del Vallès), Barcelona 08193, Spain.
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Zhang Q, Foh CH, Seet BC, Fong AC. Location estimation in wireless sensor networks using spring-relaxation technique. Sensors (Basel) 2010; 10:5171-92. [PMID: 22363204 DOI: 10.3390/s100505171] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 04/15/2010] [Accepted: 05/10/2010] [Indexed: 12/03/2022]
Abstract
Accurate and low-cost autonomous self-localization is a critical requirement of various applications of a large-scale distributed wireless sensor network (WSN). Due to its massive deployment of sensors, explicit measurements based on specialized localization hardware such as the Global Positioning System (GPS) is not practical. In this paper, we propose a low-cost WSN localization solution. Our design uses received signal strength indicators for ranging, light weight distributed algorithms based on the spring-relaxation technique for location computation, and the cooperative approach to achieve certain location estimation accuracy with a low number of nodes with known locations. We provide analysis to show the suitability of the spring-relaxation technique for WSN localization with cooperative approach, and perform simulation experiments to illustrate its accuracy in localization.
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