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2021 ◽  
Christopher Haring

The purpose of this review is to highlight LiDAR data usage for geomorphic studies and compare to other remote sensing technologies. This review further identifies survey efficiencies and issues that can be problematic in using LiDAR digital elevation models (DEMs) in completing surveys and geomorphic analysis. US Army Corps of Engineers (USACE) geospatial data collection guidance (EM 1110-1-1000) (USACE 2015) aligns with the American Society for Photogrammetry and Remote Sensing Positional Accuracy Standards for Digital Geospatial Data (ASPRS 2014). Geomorphic assessment technologies are rapidly evolving, and LiDAR data collection methods are at the forefront. The FluvialGeomorph (FG) toolbox, developed to support USACE watershed planning, is a recent example of the use of LiDAR high-resolution terrain data to provide a new, efficient approach for rapid watershed assessments (Haring et al. 2020; Haring and Biedenharn 2021). However, there are advantages and disadvantages in using LiDAR data compared to other remote sensing technologies and traditional topographic field survey methods.

2021 ◽  
Vol 11 (1) ◽  
A. Kagiava ◽  
J. Richter ◽  
C. Tryfonos ◽  
M. Leal-Julià ◽  
I. Sargiannidou ◽  

AbstractTo optimize gene delivery to myelinating Schwann cells we compared clinically relevant AAV serotypes and injection routes. AAV9 and AAVrh10 vectors expressing either EGFP or the neuropathy-associated gene GJB1/Connexin32 (Cx32) under a myelin specific promoter were injected intrathecally or intravenously in wild type and Gjb1-null mice, respectively. Vector biodistribution in lumbar roots and sciatic nerves was higher in AAVrh10 injected mice while EGFP and Cx32 expression rates and levels were similar between the two serotypes. A gradient of biodistribution away from the injection site was seen with both intrathecal and intravenous delivery, while similar expression rates were achieved despite higher vector amounts injected intravenously. Quantified immune cells in relevant tissues were similar to non-injected littermates. Overall, AAV9 and AAVrh10 efficiently transduce Schwann cells throughout the peripheral nervous system with both clinically relevant routes of administration, although AAV9 and intrathecal injection may offer a more efficient approach for treating demyelinating neuropathies.

2021 ◽  
Vol 46 (4) ◽  
Ridim D Mote ◽  
V Shinde Laxmikant ◽  
Surya Bansi Singh ◽  
Mahak Tiwari ◽  
Hemant Singh ◽  

Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Kevin Xu Zhong ◽  
Anna Cho ◽  
Christoph M. Deeg ◽  
Amy M. Chan ◽  
Curtis A. Suttle

Abstract Background The microbiome affects the health of plants and animals, including humans, and has many biological, ecological, and evolutionary consequences. Microbiome studies typically rely on sequencing ribosomal 16S RNA gene fragments, which serve as taxonomic markers for prokaryotic communities; however, for eukaryotic microbes this approach is compromised, because 18S rRNA gene sequences from microbial eukaryotes are swamped by contaminating host rRNA gene sequences. Results To overcome this problem, we developed CRISPR-Cas Selective Amplicon Sequencing (CCSAS), a high-resolution and efficient approach for characterizing eukaryotic microbiomes. CCSAS uses taxon-specific single-guide RNA (sgRNA) to direct Cas9 to cut 18S rRNA gene sequences of the host, while leaving protistan and fungal sequences intact. We validated the specificity of the sgRNA on ten model organisms and an artificially constructed (mock) community of nine protistan and fungal pathogens. The results showed that > 96.5% of host rRNA gene amplicons were cleaved, while 18S rRNA gene sequences from protists and fungi were unaffected. When used to assess the eukaryotic microbiome of oyster spat from a hatchery, CCSAS revealed a diverse community of eukaryotic microbes, typically with much less contamination from oyster 18S rRNA gene sequences than other methods using non-metazoan or blocking primers. However, each method revealed taxonomic groups that were not detected using the other methods, showing that a single approach is unlikely to uncover the entire eukaryotic microbiome in complex communities. To facilitate the application of CCSAS, we designed taxon-specific sgRNA for ~16,000 metazoan and plant taxa, making CCSAS widely available for characterizing eukaryotic microbiomes that have largely been neglected. Conclusion CCSAS provides a high-through-put and cost-effective approach for resolving the eukaryotic microbiome of metazoa and plants with minimal contamination from host 18S rRNA gene sequences.

2021 ◽  
Vol 17 ◽  
pp. 2787-2794
Alla I Vaskevych ◽  
Nataliia O Savinchuk ◽  
Ruslan I Vaskevych ◽  
Eduard B Rusanov ◽  
Oleksandr O Grygorenko ◽  

A regioselective method for the synthesis of 1-(hydroxymethyl)-2,3-dihydropyrrolo[1,2-a]quinazolin-5(1H)-ones – close structural analogs of naturally occurring vasicinone alkaloids – is described. The procedure is based on PIFA-initiated oxidative 5-exo-trig cyclization of 2-(3-butenyl)quinazolin-4(3Н)-ones, in turn prepared by thermal cyclocondensation of the corresponding 2-(pent-4-enamido)benzamides. The products obtained have a good natural product likeness (NPL) score and therefore can be useful for the design of natural product-like compound libraries.

2021 ◽  
pp. 174702182110650
Sabrina Bouhassoun ◽  
Christian Gerlach ◽  
Grégoire Borst ◽  
Nicolas Poirel

Attentional resources are limited, and resistance to interference plays a critical role during cognitive tasks and learning. Previous studies have shown that participants find it difficult to avoid being distracted by global visual information when processing local details. In this study, we investigated an innovative approach for enhancing the processing of local visual details by middle-school adolescents. Two groups completed a classic global/local visual search task in which a predefined target could appear at the global or local level, either with or without a frame. The results from the no-frame display group provided a direct replication in adolescents of previous findings in adults, with increasing number of interferent stimuli presented in the display adversely affecting detection of local targets. Additionally, by varying the numbers of distractors inside and outside the frame, we showed that distractors only interfered with the processing of local information inside the frame, while the deleterious impact of increases in distracting information was prevented when the distractors were outside the frame. These findings suggest that when a frame delimits an attentional area, the influence of an increasing number of distractors present outside the frame is eliminated. We assume that application of a frame allows for efficient delimitation of attention deployment to a restricted topographical visual area in adolescents. These results evidence that processing of local details can be improved without modifying the structure of the stimuli, and provide promising clues for optimizing attentional resources during time-absorbing visual searches. Applicable implications in the educational field are discussed.

Guan Wang ◽  
Qiang Zou ◽  
Chuke Zhao ◽  
Yusheng Liu ◽  
xiaoping YE

Abstract Bi-level programming, where one objective is nested within the other, is widely used in engineering design, e.g., structural optimization and electronic system design. One major issue of current solvers for these bi-level problems is their low computational efficiency, especially for complex nonlinear problems. To solve this issue, a new method based on bi-level grey wolf optimizer is proposed in this paper. The basic idea is to drop the time-consuming nested computational structure commonly used by existing methods and instead use a simultaneous computational structure built on top of a dominance determination process for the grey wolf optimizer. The effectiveness of this new method has been validated with ten benchmark functions and two engineering design examples, as well as comparisons with three important existing methods in the bi-level programming domain.

Wenjun Jiang ◽  
Gundra Sivakrishna Rao ◽  
Rashid Aman ◽  
Haroon Butt ◽  
Radwa Kamel ◽  

ABSTRACT Background: Retrons are a class of retroelements that produce multicopy single-stranded DNA (msDNA) and participate in anti-phage defenses in bacteria. Retrons have been harnessed for the over-production of single-stranded DNA (ssDNA), genome engineering, and directed evolution in bacteria, yeast, and mammalian cells. However, no studies have shown retron-mediated ssDNA production in plants, which could unlock potential applications in plant biotechnology. For example, ssDNA can be used as a template for homology-directed repair (HDR) in several organisms. However, current gene editing technologies rely on the physical delivery of synthetic ssDNA, which limits their applications. Main methods and major results: Here, we demonstrated retron-mediated over-production of ssDNA in Nicotiana benthamiana. Additionally, we tested different retron architectures for improved ssDNA production and identified a new retron architecture that resulted in greater ssDNA abundance. Furthermore, co-expression of the gene encoding the ssDNA-protecting protein VirE2 from Agrobacterium tumefaciens with the retron systems resulted in a 10.7-fold increase in ssDNA production in vivo. We also demonstrated CRISPR-retron-coupled ssDNA over-production and targeted HDR in N. benthamiana. Conclusion: We present an efficient approach for in vivo ssDNA production in plants, which can be harnessed for biotechnological applications.

2021 ◽  
Vol 10 (22) ◽  
pp. 5322
Kornelia Aigner ◽  
Yogesh Kumar Vashist ◽  
Emir Selak ◽  
Sabine Gailhofer ◽  
Karl Reinhard Aigner

Peritoneal spread is frequent in gastric cancer (GC) and a palliative condition. After failure to systemic chemotherapy (sCTx) remaining therapeutic options are very limited. We evaluated the feasibility and efficacy of locoregional chemotherapy (RegCTx) in peritoneal metastatic GC. In total, 38 (23 male and 15 female) patients with peritoneal metastatic GC after failure of previous sCTx and unresectable disease were enrolled in this study. Using the hypoxic abdominal stop-flow perfusion, upper abdominal perfusion and intraarterial infusion technique in total 114 cycles with Cisplatin, Adriamycin and Mitomycin C were applied. No significant procedure related toxicity was noticed- especially no Grade 3 or 4 toxicity occurred. With the RegCTx approach a median overall survival of 17.4 months was achieved. Patients who had undergone previously resection of the GC the median overall survival was even better with 23.5 months. RegCTx is a promising, safe and efficient approach in diffuse metastatic GC. The evaluation of RegCTx in the setting of multimodal treatment approach at less advanced stages is also warranted.

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