Evaluating the Sensitivity of Forest Structural Diversity Characterization to LiDAR Point Density

Recent expansion in data sharing has created unprecedented opportunities to explore structure-function linkages in ecosystems across spatial and temporal scales. However, characteristics of the same data product, such as resolution, can change over time or spatial locations, as protocols are adapted to new technology or conditions, which may impact the data’s potential utility and accuracy for addressing end user scientific questions. The National Ecological Observatory Network (NEON) provides data products for users from 81 sites and over a planned 30-year time frame, including discrete return Light Detection and Range (LiDAR) from an airborne observatory platform. LiDAR is a well-established and increasingly available remote sensing technology for measuring three-dimensional (3D) characteristics of ecosystem and landscape structure, including forest structural diversity. The LiDAR product that NEON provides can vary in point density from 2 – 25+ points/m2 depending on instrument and acquisition date. We used NEON LiDAR from five forested sites to (1) identify the minimum point density at which structural diversity metrics can be robustly estimated across forested sites from different ecoclimatic zones in the USA and (2) to test the effects of variable point density on the estimation of a suite of structural diversity metrics and multivariate structural complexity types within and across forested sites. Twelve out of sixteen structural diversity metrics were sensitive to LiDAR point density in at least one of the five NEON forested sites. The minimum point density to reliably estimate the metrics ranged from 2.0 to 7.5 pt/m2, but our results indicate that point densities above 7-8 pt/m2 should provide robust measurements of structural diversity in forests for temporal or spatial comparisons. The delineation of multivariate structural complexity types from a suite of 16 structural diversity metrics was robust within sites and across forest types for a LiDAR point density of 4 pt/m2 and above. This study shows that different metrics of structural diversity can vary in their sensitivity to the resolution of LiDAR data and users of these open-source data products should consider the point density of their data and use caution in metric selection when making spatial or temporal comparisons from these datasets.

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Needs and Gaps in Optical Underwater Technologies and Methods for the Investigation of Marine Animal Forest 3D-Structural Complexity

Frontiers in Marine Science ◽

10.3389/fmars.2021.591292 ◽

2021 ◽

Vol 8 ◽

Author(s):

Paolo Rossi ◽

Massimo Ponti ◽

Sara Righi ◽

Cristina Castagnetti ◽

Roberto Simonini ◽

...

Keyword(s):

Benthic Communities ◽

Three Dimensional ◽

Structural Complexity ◽

Marine Animal ◽

Growth Data ◽

Ecological Processes ◽

Spatial And Temporal Scales ◽

Technological Advances ◽

Data Collection And Analysis ◽

Data Acquisition And Processing

Marine animal forests are benthic communities dominated by sessile suspension feeders (such as sponges, corals, and bivalves) able to generate three-dimensional (3D) frameworks with high structural complexity. The biodiversity and functioning of marine animal forests are strictly related to their 3D complexity. The present paper aims at providing new perspectives in underwater optical surveys. Starting from the current gaps in data collection and analysis that critically limit the study and conservation of marine animal forests, we discuss the main technological and methodological needs for the investigation of their 3D structural complexity at different spatial and temporal scales. Despite recent technological advances, it seems that several issues in data acquisition and processing need to be solved, to properly map the different benthic habitats in which marine animal forests are present, their health status and to measure structural complexity. Proper precision and accuracy should be chosen and assured in relation to the biological and ecological processes investigated. Besides, standardized methods and protocols are strictly necessary to meet the FAIR (findability, accessibility, interoperability, and reusability) data principles for the stewardship of habitat mapping and biodiversity, biomass, and growth data.

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Three-Dimensional Structure of Dendritic Spines Revealed by Volume Electron Microscopy Techniques

Frontiers in Neuroanatomy ◽

10.3389/fnana.2021.627368 ◽

2021 ◽

Vol 15 ◽

Author(s):

Laxmi Kumar Parajuli ◽

Masato Koike

Keyword(s):

Electron Microscopy ◽

Synaptic Transmission ◽

Three Dimensional ◽

Morphological Characteristics ◽

Structural Diversity ◽

Time Frame ◽

Relative Magnitude ◽

Dimensional Structure ◽

Synaptic Ultrastructure ◽

The Brain

Electron microscopy (EM)-based synaptology is a fundamental discipline for achieving a complex wiring diagram of the brain. A quantitative understanding of synaptic ultrastructure also serves as a basis to estimate the relative magnitude of synaptic transmission across individual circuits in the brain. Although conventional light microscopic techniques have substantially contributed to our ever-increasing understanding of the morphological characteristics of the putative synaptic junctions, EM is the gold standard for systematic visualization of the synaptic morphology. Furthermore, a complete three-dimensional reconstruction of an individual synaptic profile is required for the precise quantitation of different parameters that shape synaptic transmission. While volumetric imaging of synapses can be routinely obtained from the transmission EM (TEM) imaging of ultrathin sections, it requires an unimaginable amount of effort and time to reconstruct very long segments of dendrites and their spines from the serial section TEM images. The challenges of low throughput EM imaging have been addressed to an appreciable degree by the development of automated EM imaging tools that allow imaging and reconstruction of dendritic segments in a realistic time frame. Here, we review studies that have been instrumental in determining the three-dimensional ultrastructure of synapses. With a particular focus on dendritic spine synapses in the rodent brain, we discuss various key studies that have highlighted the structural diversity of spines, the principles of their organization in the dendrites, their presynaptic wiring patterns, and their activity-dependent structural remodeling.

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The Recent Revolution in High Performance Computing

MRS Bulletin ◽

10.1557/s0883769400034096 ◽

1997 ◽

Vol 22 (10) ◽

pp. 5-6

Author(s):

Horst D. Simon

Keyword(s):

High Performance Computing ◽

High Performance ◽

New Technologies ◽

New Technology ◽

Parallel Architecture ◽

Time Frame ◽

Good News ◽

Computing Industry ◽

Time And Energy ◽

Performance Computing

Recent events in the high-performance computing industry have concerned scientists and the general public regarding a crisis or a lack of leadership in the field. That concern is understandable considering the industry's history from 1993 to 1996. Cray Research, the historic leader in supercomputing technology, was unable to survive financially as an independent company and was acquired by Silicon Graphics. Two ambitious new companies that introduced new technologies in the late 1980s and early 1990s—Thinking Machines and Kendall Square Research—were commercial failures and went out of business. And Intel, which introduced its Paragon supercomputer in 1994, discontinued production only two years later.During the same time frame, scientists who had finished the laborious task of writing scientific codes to run on vector parallel supercomputers learned that those codes would have to be rewritten if they were to run on the next-generation, highly parallel architecture. Scientists who are not yet involved in high-performance computing are understandably hesitant about committing their time and energy to such an apparently unstable enterprise.However, beneath the commercial chaos of the last several years, a technological revolution has been occurring. The good news is that the revolution is over, leading to five to ten years of predictable stability, steady improvements in system performance, and increased productivity for scientific applications. It is time for scientists who were sitting on the fence to jump in and reap the benefits of the new technology.

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Clinical Value of Computer-Assisted Taylor Three-dimensional External Fixation in the Treatment of Tibiofibular Fracture (Preprint)

10.2196/preprints.20711 ◽

2020 ◽

Author(s):

Hongfeng Sheng ◽

Weixing Xu ◽

Bin Xu ◽

Hongpu Song ◽

Di Lu ◽

...

Keyword(s):

Retrospective Study ◽

Internal Fixation ◽

External Fixation ◽

External Fixator ◽

Theoretical Basis ◽

New Technology ◽

Three Dimensional ◽

Computer Assisted ◽

Clinical Value

UNSTRUCTURED The retrospective study of Taylor's three-dimensional external fixator for the treatment of tibiofibular fractures provides a theoretical basis for the application of this technology. The paper collected 28 patients with tibiofibular fractures from the Department of Orthopaedics in our hospital from March 2015 to June 2018. After the treatment, the follow-up evaluation of Taylor's three-dimensional external fixator for the treatment of tibiofibular fractures and concurrency the incidence of the disease, as well as the efficacy and occurrence of the internal fixation of the treatment of tibial fractures in our hospital. The results showed that Taylor's three-dimensional external fixator was superior to orthopaedics in the treatment of tibiofibular fractures in terms of efficacy and complications. To this end, the thesis research can be concluded as follows: Taylor three-dimensional external fixation in the treatment of tibiofibular fractures is more effective, and the incidence of occurrence is low, is a new technology for the treatment of tibiofibular fractures, it is worthy of clinical promotion.

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The structural complexity index SCI is useful for quantifying structural diversity of Estonian hemiboreal forests

Forest Ecology and Management ◽

10.1016/j.foreco.2021.119093 ◽

2021 ◽

Vol 490 ◽

pp. 119093

Author(s):

Eneli Põldveer ◽

Aleksei Potapov ◽

Henn Korjus ◽

Andres Kiviste ◽

John A. Stanturf ◽

...

Keyword(s):

Structural Complexity ◽

Structural Diversity ◽

Complexity Index

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3D Reconstruction of Cultural Heritage Sites as an Educational Approach. The Sanctuary of Delphi

Applied Sciences ◽

10.3390/app11083635 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3635

Author(s):

Ioannis Liritzis ◽

Pantelis Volonakis ◽

Spyros Vosinakis

Keyword(s):

University Students ◽

3D Reconstruction ◽

Cultural Heritage ◽

New Technology ◽

Three Dimensional ◽

Computer Gaming ◽

Educational Approach ◽

Heritage Sites ◽

3D Environment ◽

Almost All

In the field of cultural heritage, three-dimensional (3D) reconstruction of monuments is a usual activity for many professionals. The aim in this paper focuses on the new technology educational application combining science, history, and archaeology. Being involved in almost all stages of implementation steps and assessing the level of participation, university students use tools of computer gaming platform and participate in ways of planning the virtual environment which improves their education through e-Learning. The virtual 3D environment is made with different imaging methods (helium-filled balloon, Structure for motion, 3D repository models) and a developmental plan has been designed for use in many future applications. Digital tools were used with 3D reconstructed buildings from the museum archive to Unity 3D for the design. The pilot study of Information Technology work has been employed to introduce cultural heritage and archaeology to university syllabuses. It included students with a questionnaire which has been evaluated accordingly. As a result, the university students were inspired to immerse themselves into the virtual lab, aiming to increasing the level of interaction. The results show a satisfactory learning outcome by an easy to use and real 3D environment, a step forward to fill in needs of contemporary online sustainable learning demands.

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3DP Printing of Oral Solid Formulations: A Systematic Review

Pharmaceutics ◽

10.3390/pharmaceutics13030358 ◽

2021 ◽

Vol 13 (3) ◽

pp. 358 ◽

Cited By ~ 1

Author(s):

Chiara R. M. Brambilla ◽

Ogochukwu Lilian Okafor-Muo ◽

Hany Hassanin ◽

Amr ElShaer

Keyword(s):

Systematic Review ◽

Data Extraction ◽

New Technology ◽

Three Dimensional ◽

Extraction Process ◽

Carcinogenic Risk ◽

Drug Dissolution ◽

Dissolution Profile ◽

Disintegration Time ◽

Advantages And Disadvantages

Three-dimensional (3D) printing is a recent technology, which gives the possibility to manufacture personalised dosage forms and it has a broad range of applications. One of the most developed, it is the manufacture of oral solid dosage and the four 3DP techniques which have been more used for their manufacture are FDM, inkjet 3DP, SLA and SLS. This systematic review is carried out to statistically analyze the current 3DP techniques employed in manufacturing oral solid formulations and assess the recent trends of this new technology. The work has been organised into four steps, (1) screening of the articles, definition of the inclusion and exclusion criteria and classification of the articles in the two main groups (included/excluded); (2) quantification and characterisation of the included articles; (3) evaluation of the validity of data and data extraction process; (4) data analysis, discussion, and conclusion to define which technique offers the best properties to be applied in the manufacture of oral solid formulations. It has been observed that with SLS 3DP technique, all the characterisation tests required by the BP (drug content, drug dissolution profile, hardness, friability, disintegration time and uniformity of weight) have been performed in the majority of articles, except for the friability test. However, it is not possible to define which of the four 3DP techniques is the most suitable for the manufacture of oral solid formulations, because the selection is affected by different parameters, such as the type of formulation, the physical-mechanical properties to achieve. Moreover, each technique has its specific advantages and disadvantages, such as for FDM the biggest challenge is the degradation of the drug, due to high printing temperature process or for SLA is the toxicity of the carcinogenic risk of the photopolymerising material.

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Human iPSC-Based Modeling of Central Nerve System Disorders for Drug Discovery

International Journal of Molecular Sciences ◽

10.3390/ijms22031203 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1203

Author(s):

Lu Qian ◽

Julia TCW

Keyword(s):

Drug Discovery ◽

Disease Modeling ◽

Three Dimensional ◽

Structural Complexity ◽

Induced Pluripotent Stem Cell ◽

Cell Types ◽

Central Nerve System ◽

Human Ipscs ◽

Nerve System

A high-throughput drug screen identifies potentially promising therapeutics for clinical trials. However, limitations that persist in current disease modeling with limited physiological relevancy of human patients skew drug responses, hamper translation of clinical efficacy, and contribute to high clinical attritions. The emergence of induced pluripotent stem cell (iPSC) technology revolutionizes the paradigm of drug discovery. In particular, iPSC-based three-dimensional (3D) tissue engineering that appears as a promising vehicle of in vitro disease modeling provides more sophisticated tissue architectures and micro-environmental cues than a traditional two-dimensional (2D) culture. Here we discuss 3D based organoids/spheroids that construct the advanced modeling with evolved structural complexity, which propels drug discovery by exhibiting more human specific and diverse pathologies that are not perceived in 2D or animal models. We will then focus on various central nerve system (CNS) disease modeling using human iPSCs, leading to uncovering disease pathogenesis that guides the development of therapeutic strategies. Finally, we will address new opportunities of iPSC-assisted drug discovery with multi-disciplinary approaches from bioengineering to Omics technology. Despite technological challenges, iPSC-derived cytoarchitectures through interactions of diverse cell types mimic patients’ CNS and serve as a platform for therapeutic development and personalized precision medicine.

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Three-Dimensional Structures of Carbohydrates and Where to Find Them

International Journal of Molecular Sciences ◽

10.3390/ijms21207702 ◽

2020 ◽

Vol 21 (20) ◽

pp. 7702 ◽

Cited By ~ 1

Author(s):

Sofya I. Scherbinina ◽

Philip V. Toukach

Keyword(s):

Experimental Data ◽

Molecular Modeling ◽

Computational Methods ◽

Three Dimensional ◽

Structural Diversity ◽

Structural Data ◽

Structural Features ◽

Data Validation ◽

Data Generation ◽

Efficient Treatment

Analysis and systematization of accumulated data on carbohydrate structural diversity is a subject of great interest for structural glycobiology. Despite being a challenging task, development of computational methods for efficient treatment and management of spatial (3D) structural features of carbohydrates breaks new ground in modern glycoscience. This review is dedicated to approaches of chemo- and glyco-informatics towards 3D structural data generation, deposition and processing in regard to carbohydrates and their derivatives. Databases, molecular modeling and experimental data validation services, and structure visualization facilities developed for last five years are reviewed.

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Preoperative Use of CT Angiography in Infants With Coarctation of the Aorta

World Journal for Pediatric and Congenital Heart Surgery ◽

10.1177/2150135116683929 ◽

2017 ◽

Vol 8 (2) ◽

pp. 196-202 ◽

Cited By ~ 8

Author(s):

Kirsten Rose-Felker ◽

Joshua D. Robinson ◽

Carl L. Backer ◽

Cynthia K. Rigsby ◽

Osama M. Eltayeb ◽

...

Keyword(s):

Radiation Dose ◽

Surgical Approach ◽

New Technology ◽

Three Dimensional ◽

Coarctation Of The Aorta ◽

Computed Tomographic Angiography ◽

Great Vessel ◽

Z Score ◽

Computed Tomographic ◽

Tomographic Angiography

Background: Computed tomographic angiography (CTA) and echocardiography (echo) are used preoperatively in coarctation of the aorta to define arch hypoplasia and great vessel branching. We sought to determine differences in quantitative measurements, as well as surgical utility, between modalities. Methods: Infants (less than six months) with both CTA and echo prior to coarctation repair from 2004 to 2013 were included. Measurements were compared and correlated with surgical approach. Three surgeons reviewed de-identified images to predict approach and characterize utility. Computed tomographic angiography radiation dose was calculated. Results: Thirty-three patients were included. No differences existed in arch measurements between echo and CTA ( z-score: −2.59 vs −2.43; P = .47). No differences between modalities were seen for thoracotomy ( z-score: −2.48 [echo] vs −2.31 [CTA]; P = .48) or sternotomy ( z-score: −3.13 [echo] vs −3.08 [CTA]; P = .84). Computed tomographic angiography delineated great vessel branching pattern in two patients with equivocal echo findings ( P = .60). Surgeons rated CTA as far more useful than echo in understanding arch hypoplasia and great vessel branching in cases where CTA was done to resolve anatomical questions that remain after echo evaluation. Two of three surgeons were more likely to choose the surgical approach taken based on CTA (surgeon A, P = .02; surgeon B, P = .01). Radiation dose averaged 2.5 (1.6) mSv and trended down from 2.9 mSv (1.8 mSv; n = 20) to 1.6 mSv (0.5 mSv; n = 7) ( P = .06) with new technology. Conclusion: Although CTA and echo measurements of the aorta do not differ, CTA better delineates branching and surgeons strongly prefer it for three-dimensional arch anatomy. We recommend CTA for patients with anomalous arch branching patterns, diffuse or complex hypoplasia, or unusual arch morphology not fully elucidated by echo.

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