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1.
Neurosurgery ; 2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38206045

ABSTRACT

Skull base surgery is a young surgical subspecialty currently led by its second generation of surgeons. At present, there is no literature that narrates the connection of the present to the past. An extended interview was held with Dr Jon H. Robertson, who helped establish the subspecialty in Memphis, TN, to aid in identifying and connecting sentinel events and key figures in the development of the discipline. The field drastically evolved during his era of practice (1975-present), with the advent of advanced imaging and technology, as well as the emergence of multidisciplinary skull base surgical teams. The intersection of the careers of Jon H. Robertson, James T. Robertson, Gale Gardner, Edwin Cocke, John Shea, Jr., and Jerrall Crook in Memphis catalyzed the standardization of a multidisciplinary approach to cranial base pathology. We report the findings of Dr Jon H. Robertson's extended interview, told against the backdrop of the history of the subspecialty. The story of the development of skull base surgery is told from the unique perspective of one who lived and shaped a pivotal segment in this historical timeline.

2.
Cureus ; 13(11): e19638, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34956763

ABSTRACT

Introduction Lesions of the jugular foramen (JF) and postero-lateral skull base are difficult to expose and exhibit complex neurovascular relationships. Given their rarity and the increasing use of radiosurgery, neurosurgeons are becoming less experienced with their surgical management. Anatomical factors are crucial in designing the approach to achieve a maximal safe resection. Methods and methods Six cadaveric heads (12 sides) were dissected via combined post-auricular infralabyrinthine and distal transcervical approach with additional anterior transstyloid and posterior far lateral exposures. Contiguous surgical triangles were measured, and contents were analyzed. Thirty-one patients (32 lesions) were treated surgically between 2000 and 2016 through different variations of the retro-auricular distal cervical transtemporal approaches. Results We anatomically reviewed the carotid, stylodigastric, jugular, condylar, suboccipital, deep condylar, mastoid, suprajugular, suprahypoglossal (infrajugular), and infrahypoglossal triangles. Tumors included glomus jugulare, lower cranial nerve schwannomas or neurofibromas, meningiomas, chondrosarcoma, adenocystic carcinoma, plasmacytoma of the occipitocervical joint, and a sarcoid lesion. We classified tumors into extracranial, intradural, intraosseous, and dumbbell-shaped, and analyzed the approach selection for each. Conclusion Jugular foramen and posterolateral skull base lesions can be safely resected through a retro-auricular distal cervical lateral skull base approach, which is customizable to anatomical location and tumor extension by tailoring the involved osteo-muscular triangles.

3.
PLoS One ; 16(8): e0255922, 2021.
Article in English | MEDLINE | ID: mdl-34388196

ABSTRACT

Tillering and secondary branching are two plastic traits with high agronomic importance, especially in terms of the ability of plants to adapt to changing environments. We describe a quantitative trait analysis of tillering and secondary branching in two novel BC1F2 populations totaling 246 genotypes derived from backcrossing two Sorghum bicolor x S. halepense F1 plants to a tetraploidized S. bicolor. A two-year, two-environment phenotypic evaluation in Bogart, GA and Salina, KS permitted us to identify major effect and environment specific QTLs. Significant correlation between tillering and secondary branching followed by discovery of overlapping sets of QTLs continue to support the developmental relationship between these two organs and suggest the possibility of pleiotropy. Comparisons with two other populations sharing S. bicolor BTx623 as a common parent but sampling the breadth of the Sorghum genus, increase confidence in QTL detected for these two plastic traits and provide insight into the evolution of morphological diversity in the Eusorghum clade. Correspondence between flowering time and vegetative branching supports other evidence in suggesting a pleiotropic effect of flowering genes. We propose a model to predict biomass weight from plant architecture related traits, quantifying contribution of each trait to biomass and providing guidance for future breeding experiments.


Subject(s)
Plant Breeding , Sorghum , Chromosome Mapping , Phenotype , Quantitative Trait Loci
4.
Int J Chron Obstruct Pulmon Dis ; 16: 1607-1619, 2021.
Article in English | MEDLINE | ID: mdl-34113093

ABSTRACT

Purpose: This study evaluated the safety and efficacy of inhaled nemiralisib, a phosphoinositide 3-kinase δ (PI3Kδ) inhibitor, in patients with an acute exacerbation of chronic obstructive pulmonary disease (COPD). Methods: In this double-blind, placebo-controlled study, 126 patients (40-80 years with a post-bronchodilator forced expiratory volume in 1 sec (FEV1) ≤80% of predicted (previously documented)) were randomized 1:1 to once daily inhaled nemiralisib (1 mg) or placebo for 84 days, added to standard of care. The primary endpoint was specific imaging airway volume (siVaw) after 28 treatment days and was analyzed using a Bayesian repeated measures model (clintrials.gov: NCT02294734). Results: A total of 126 patients were randomized to treatment; 55 on active treatment and 49 on placebo completed the study. When comparing nemiralisib and placebo-treated patients, an 18% placebo-corrected increase from baseline in distal siVaw (95% credible intervals (Cr I) (-1%, 42%)) was observed on Day 28. The probability that the true treatment ratio was >0% (Pr(θ>0)) was 96%, suggestive of a real treatment effect. Improvements were observed across all lung lobes. Patients treated with nemiralisib experienced a 107.3 mL improvement in posterior median FEV1 (change from baseline, 95% Cr I (-2.1, 215.5)) at day 84, compared with placebo. Adverse events were reported by 41 patients on placebo and 49 on nemiralisib, the most common being post-inhalation cough on nemiralisib (35%) vs placebo (3%). Conclusion: These data show that addition of nemiralisib to usual care delivers more effective recovery from an acute exacerbation and improves lung function parameters including siVaw and FEV1. Although post-inhalation cough was identified, nemiralisib was otherwise well tolerated, providing a promising novel therapy for this acutely ill patient group.


Subject(s)
Phosphatidylinositol 3-Kinases , Pulmonary Disease, Chronic Obstructive , Administration, Inhalation , Bayes Theorem , Bronchodilator Agents/therapeutic use , Double-Blind Method , Forced Expiratory Volume , Humans , Phosphatidylinositol 3-Kinases/pharmacology , Phosphatidylinositol 3-Kinases/therapeutic use , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/drug therapy , Treatment Outcome
5.
Int J Chron Obstruct Pulmon Dis ; 16: 1637-1646, 2021.
Article in English | MEDLINE | ID: mdl-34113095

ABSTRACT

Background: Management of acute exacerbations of chronic obstructive pulmonary disease (COPD) is sometimes inadequate leading to either prolonged duration and/or an increased risk of recurrent exacerbations in the period following the initial event. Objective: To evaluate the safety and efficacy of inhaled nemiralisib, a phosphoinositide 3-kinase δ inhibitor, in patients experiencing an acute exacerbation of COPD. Patients and Methods: In this double-blind, placebo-controlled study, COPD patients (40-80 years, ≥10 pack-year smoking history, current moderate/severe acute exacerbation of COPD requiring standard-of-care treatment) were randomized to placebo or nemiralisib 12.5 µg, 50 µg, 100 µg, 250 µg, 500 µg, or 750 µg (ratio of 3:1:1:1:1:1:3; N=938) for 12 weeks with an exploratory 12-week follow-up period. The primary endpoint was change from baseline in post-bronchodilator FEV1 at week 12. Key secondary endpoints were rate of re-exacerbations, patient-reported outcomes (Exacerbations of Chronic Pulmonary Disease Tool, COPD Assessment Test, St George's Respiratory Questionnaire-COPD), plasma pharmacokinetics (PK) and safety/tolerability. Results: There was no difference in change from baseline FEV1 at week 12 between the nemiralisib and placebo treatment groups (posterior adjusted median difference, nemiralisib 750 µg and placebo: -0.004L (95% CrI: -0.051L to 0.042L)). Overall, there were also no differences between nemiralisib and placebo in secondary endpoints, including re-exacerbations. Plasma PK increased in a dose proportional manner. The most common adverse event for nemiralisib was post-inhalation cough which appeared to be dose-related. Conclusion: The addition of nemiralisib to standard-of-care treatment for 12 weeks did not improve lung function or re-exacerbations in patients with, and following an acute exacerbation of COPD. However, this study demonstrated that large clinical trials recruiting acutely exacerbating patients can successfully be conducted.


Subject(s)
Phosphatidylinositol 3-Kinases , Pulmonary Disease, Chronic Obstructive , Bronchodilator Agents/therapeutic use , Double-Blind Method , Forced Expiratory Volume , Humans , Indazoles , Indoles , Oxazoles/pharmacology , Oxazoles/therapeutic use , Phosphatidylinositol 3-Kinases/pharmacology , Phosphatidylinositol 3-Kinases/therapeutic use , Piperazines , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/drug therapy
6.
Pharm Stat ; 20(6): 1102-1111, 2021 11.
Article in English | MEDLINE | ID: mdl-33960600

ABSTRACT

In this paper, we extend the use of assurance for a single study to explore how meeting a study's pre-defined success criteria could update our beliefs about the true treatment effect and impact the assurance of subsequent studies. This concept of conditional assurance, the assurance of a subsequent study conditional on success in an initial study, can be used assess the de-risking potential of the study requiring immediate investment, to ensure it provides value within the overall development plan. If the planned study does not discharge sufficient later phase risk, alternative designs and/or success criteria should be explored. By transparently laying out the different design options and the risks associated, this allows for decision makers to make quantitative investment choices based on their risk tolerance levels and potential return on investment. This paper lays out the derivation of conditional assurance, discusses how changing the design of a planned study will impact the conditional assurance of a future study, as well as presenting a simple illustrative example of how this methodology could be used to transparently compare development plans to aid decision making within an organisation.


Subject(s)
Drug Development
7.
Hortic Res ; 8(1): 37, 2021 Feb 11.
Article in English | MEDLINE | ID: mdl-33574224

ABSTRACT

Betula L. (birch) is a pioneer hardwood tree species with ecological, economic, and evolutionary importance in the Northern Hemisphere. We sequenced the Betula platyphylla genome and assembled the sequences into 14 chromosomes. The Betula genome lacks evidence of recent whole-genome duplication and has the same paleoploidy level as Vitis vinifera and Prunus mume. Phylogenetic analysis of lignin pathway genes coupled with tissue-specific expression patterns provided clues for understanding the formation of higher ratios of syringyl to guaiacyl lignin observed in Betula species. Our transcriptome analysis of leaf tissues under a time-series cold stress experiment revealed the presence of the MEKK1-MKK2-MPK4 cascade and six additional mitogen-activated protein kinases that can be linked to a gene regulatory network involving many transcription factors and cold tolerance genes. Our genomic and transcriptome analyses provide insight into the structures, features, and evolution of the B. platyphylla genome. The chromosome-level genome and gene resources of B. platyphylla obtained in this study will facilitate the identification of important and essential genes governing important traits of trees and genetic improvement of B. platyphylla.

8.
Theor Appl Genet ; 134(4): 1185-1200, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33423085

ABSTRACT

KEY MESSAGE: Comparing populations derived, respectively, from polyploid Sorghum halepense and its progenitors improved knowledge of plant architecture and showed that S. halepense harbors genetic novelty of potential value for sorghum improvement Vegetative growth and the timing of the vegetative-to-reproductive transition are critical to a plant's fitness, directly and indirectly determining when and how a plant lives, grows and reproduces. We describe quantitative trait analysis of plant height and flowering time in the naturally occurring tetraploid Sorghum halepense, using two novel BC1F2 populations totaling 246 genotypes derived from backcrossing two tetraploid Sorghum bicolor x S. halepense F1 plants to a tetraploidized S. bicolor. Phenotyping for two years each in Bogart, GA and Salina, KS allowed us to dissect variance into narrow-sense genetic (QTLs) and environmental components. In crosses with a common S. bicolor BTx623 parent, comparison of QTLs in S. halepense, its rhizomatous progenitor S. propinquum and S. bicolor race guinea which is highly divergent from BTx623 permit inferences of loci at which new alleles have been associated with improvement of elite sorghums. The relative abundance of QTLs unique to the S. halepense populations may reflect its polyploidy and subsequent 'diploidization' processes often associated with the formation of genetic novelty, a possibility further supported by a high level of QTL polymorphism within sibling lines derived from a common S. halepense parent. An intriguing hypothesis for further investigation is that polyploidy of S. halepense following 96 million years of abstinence, coupled with natural selection during its spread to diverse environments across six continents, may provide a rich collection of novel alleles that offer potential opportunities for sorghum improvement.


Subject(s)
Chromosome Mapping/methods , Chromosomes, Plant/genetics , Quantitative Trait Loci , Sorghum/classification , Sorghum/genetics , Crosses, Genetic , Phenotype
9.
Plant Methods ; 16(1): 156, 2020 Dec 07.
Article in English | MEDLINE | ID: mdl-33372635

ABSTRACT

BACKGROUND: Flowering is one of the most important processes for flowering plants such as cotton, reflecting the transition from vegetative to reproductive growth and is of central importance to crop yield and adaptability. Conventionally, categorical scoring systems have been widely used to study flowering patterns, which are laborious and subjective to apply. The goal of this study was to develop a deep learning-based approach to characterize flowering patterns for cotton plants that flower progressively over several weeks, with flowers distributed across much of the plant. RESULTS: A ground mobile system (GPhenoVision) was modified with a multi-view color imaging module, to acquire images of a plant from four viewing angles at a time. A total of 116 plants from 23 genotypes were imaged during an approximately 2-month period with an average scanning interval of 2-3 days, yielding a dataset containing 8666 images. A subset (475) of the images were randomly selected and manually annotated to form datasets for training and selecting the best object detection model. With the best model, a deep learning-based approach (DeepFlower) was developed to detect and count individual emerging blooms for a plant on a given date. The DeepFlower was used to process all images to obtain bloom counts for individual plants over the flowering period, using the resulting counts to derive flowering curves (and thus flowering characteristics). Regression analyses showed that the DeepFlower method could accurately (R2 = 0.88 and RMSE = 0.79) detect and count emerging blooms on cotton plants, and statistical analyses showed that imaging-derived flowering characteristics had similar effectiveness as manual assessment for identifying differences among genetic categories or genotypes. CONCLUSIONS: The developed approach could thus be an effective and efficient tool to characterize flowering patterns for flowering plants (such as cotton) with complex canopy architecture.

10.
J Neurosurg ; : 1-8, 2020 Aug 07.
Article in English | MEDLINE | ID: mdl-32764183

ABSTRACT

OBJECTIVE: The Neurosurgery Research & Education Foundation (NREF), previously known as the Research Foundation of the American Association of Neurological Surgeons (AANS), was established in 1980 to encourage and facilitate innovation through financial support to young neurosurgeons in the process of honing their competencies in neurosciences and neurological surgery. This article provides a historical overview of NREF, its mission, and charitable contributions and the ever-expanding avenues for neurosurgeons, neurosurgical residents and fellows, and medical students to supplement clinical training and to further neurosurgical research advances. METHODS: Data were collected from the historical archives of the AANS and NREF website. Available data included tabulated revenue, geographic and institutional records of funding, changes in funding for fellowships and awards, advertising methods, and sources of funding. RESULTS: Since 1984, NREF has invested more than $23 million into the future of neurosurgery. To date, NREF has provided more than 500 fellowship opportunities which have funded neurosurgeons' education and research efforts at all stages of training and practice. CONCLUSIONS: NREF is designed to serve as the vehicle through which the neurosurgical community fosters the continued excellence in the care of patients with neurosurgical diseases.

11.
Front Plant Sci ; 11: 467, 2020.
Article in English | MEDLINE | ID: mdl-32425964

ABSTRACT

Despite a "ploidy barrier," interspecific crosses to wild and/or cultivated sorghum (Sorghum bicolor, 2n = 2x = 20) may have aided the spread across six continents of Sorghum halepense, also exemplifying risks of "transgene escape" from crops that could make weeds more difficult to control. Genetic maps of two BC1F1 populations derived from crosses of S. bicolor (sorghum) and S. halepense with totals of 722 and 795 single nucleotide polymorphism (SNP) markers span 37 and 35 linkage groups, with 2-6 for each of the 10 basic sorghum chromosomes due to fragments covering different chromosomal portions or independent segregation from different S. halepense homologs. Segregation distortion favored S. halepense alleles on chromosomes 2 (1.06-4.68 Mb, near a fertility restoration gene), 7 (1.20-6.16 Mb), 8 (1.81-5.33 Mb, associated with gene conversion), and 9 (47.5-50.1 Mb); and S. bicolor alleles on chromosome 6 (0-40 Mb), which contains both a large heterochromatin block and the Ma1 gene. Regions of the S. halepense genome that are recalcitrant to gene flow from sorghum might be exploited as part a multi-component system to reduce the likelihood of spread of transgenes or other modified genes. Its SNP profile suggests that chromosome segments from its respective progenitors S. bicolor and Sorghum propinquum have extensively recombined in S. halepense. This study reveals genomic regions that might discourage crop-to-weed gene escape, and provides a foundation for marker-trait association analysis to determine the genetic control of traits contributing to weediness, invasiveness, and perenniality of S. halepense.

12.
Plant Methods ; 15: 141, 2019.
Article in English | MEDLINE | ID: mdl-31768186

ABSTRACT

BACKGROUND: Plant population density is an important factor for agricultural production systems due to its substantial influence on crop yield and quality. Traditionally, plant population density is estimated by using either field assessment or a germination-test-based approach. These approaches can be laborious and inaccurate. Recent advances in deep learning provide new tools to solve challenging computer vision tasks such as object detection, which can be used for detecting and counting plant seedlings in the field. The goal of this study was to develop a deep-learning-based approach to count plant seedlings in the field. RESULTS: Overall, the final detection model achieved F1 scores of 0.727 (at I O U all ) and 0.969 (at I O U 0.5 ) on the S e e d l i n g All testing set in which images had large variations, indicating the efficacy of the Faster RCNN model with the Inception ResNet v2 feature extractor for seedling detection. Ablation experiments showed that training data complexity substantially affected model generalizability, transfer learning efficiency, and detection performance improvements due to increased training sample size. Generally, the seedling counts by the developed method were highly correlated ( R 2 = 0.98) with that found through human field assessment for 75 test videos collected in multiple locations during multiple years, indicating the accuracy of the developed approach. Further experiments showed that the counting accuracy was largely affected by the detection accuracy: the developed approach provided good counting performance for unknown datasets as long as detection models were well generalized to those datasets. CONCLUSION: The developed deep-learning-based approach can accurately count plant seedlings in the field. Seedling detection models trained in this study and the annotated images can be used by the research community and the cotton industry to further the development of solutions for seedling detection and counting.

13.
J Neurol Surg B Skull Base ; 80(5): 518-526, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31534895

ABSTRACT

Introduction The jugular foramen occupies a complex and deep location between the skull base and the distal-lateral-cervical region. We propose a morphometric anatomical model to deconstruct its surgical anatomy and offer various quantifiable target-guided exposures and angles-of-attack. Methods Six cadaveric heads (12 sides) were dissected using a combined postauricular infralabyrinthine and distal transcervical approach with additional anterior transstyloid and posterior far lateral exposures. We identified anatomical landmarks and combined new and previously described contiguous triangles to expose the region; we defined the jugular and deep condylar triangles. Angles-of-attack to the jugular foramen were measured after removing the digastric muscle, styloid process, rectus capitis lateralis, and occipital condyle. Results Removing the digastric muscle and styloid process allowed 86.4° laterally and 85.5° anteriorly, respectively. Resecting the rectus capitis lateralis and jugular process provided the largest angle-of-attack (108.4° posteriorly). The occipital condyle can be drilled in the deep condylar triangle only adding 30.4° medially. A purely lateral approach provided a total of 280.3°. Cutting the jugular ring and mobilizing the vein can further expand the medial exposure. Conclusion The microsurgical anatomy of the jugular foramen can be deconstructed using a morphometric model, permitting a surgical approach customized to the pathology of interest.

14.
J Pharmacol Exp Ther ; 367(3): 405-413, 2018 12.
Article in English | MEDLINE | ID: mdl-30217958

ABSTRACT

Phosphoinositide 3-kinase δ (PI3Kδ) is a lipid kinase involved in leukocyte recruitment and activation. Activation of PI3Kδ has been linked to airway inflammation and asthma pathogenesis. This randomized, double-blind, placebo-controlled, crossover study investigated the efficacy, safety, tolerability, and pharmacokinetics of a PI3Kδ inhibitor, nemiralisib (GSK2269557), in patients with persistent, uncontrolled asthma. Patients (n = 50) received once-daily inhaled nemiralisib (1000 µg) or placebo for 28 days, with a crossover to the alternative treatment following a 4-week washout period. Spirometry demonstrated no discernible difference in trough forced expiratory volume in 1 second (FEV1) from baseline (adjusted posterior median 7 ml; 95% credible interval -83, 102 ml) between nemiralisib and placebo treatment at day 28 (primary endpoint). These results were supported by most secondary endpoints, including weighted mean FEV1 (0-4 hours) and change in trough forced vital capacity at day 28. Nemiralisib was generally well-tolerated, with few side effects except for post-inhalation cough (nemiralisib: 35%; placebo: 9%). At day 14, sputum interleukin (IL)-5, IL-13, IL-6, and IL-8 levels were reduced by a median of 17%, 7%, 15%, and 8%, respectively, when comparing nemiralisib with placebo [n = 15 (IL-5, IL-8) or 16 (IL-6, IL-13); posterior probability of a true ratio >0%: 78%, 64%, 76%, and 63%, respectively]. These results suggest that nemiralisib inhibited PI3Kδ locally; however, this did not translate into meaningful clinical improvement. Further studies will investigate the potential efficacy of nemiralisib in patients with asthma with other specific more severe phenotypes, including those who are colonized with bacteria and frequently exacerbate.


Subject(s)
Asthma/drug therapy , Bronchodilator Agents/administration & dosage , Indazoles/administration & dosage , Indoles/administration & dosage , Oxazoles/administration & dosage , Piperazines/administration & dosage , Administration, Inhalation , Adrenergic beta-2 Receptor Agonists/administration & dosage , Adult , Aged , Asthma/metabolism , Cross-Over Studies , Double-Blind Method , Female , Forced Expiratory Volume/drug effects , Humans , Male , Middle Aged , Phosphatidylinositol 3-Kinases/metabolism , Vital Capacity/drug effects , Young Adult
15.
G3 (Bethesda) ; 8(8): 2563-2572, 2018 07 31.
Article in English | MEDLINE | ID: mdl-29853656

ABSTRACT

We describe a genetic map with a total of 381 bins of 616 genotyping by sequencing (GBS)-based SNP markers in a F6-F8 recombinant inbred line (RIL) population of 393 individuals derived from crossing S. bicolor BTx623 to S. bicolor IS3620C, a guinea line substantially diverged from BTx623. Five segregation distorted regions were found with four showing enrichment for S. bicolor alleles, suggesting possible selection during formation of this RIL population. A quantitative trait locus (QTL) study with this number of individuals, tripled relative to prior studies of this cross, provided resources, validated previous findings, and demonstrated improved power to detect plant height and flowering time related QTL relative to other published studies. An unexpected low correlation between flowering time and plant height permitted us to separate QTL for each trait and provide evidence against pleiotropy. Ten non- random syntenic regions conferring QTL for the same trait suggest that those QTL may represent alleles at genes functioning in the same manner since the 96 million year ago genome duplication that created these syntenic relationships, while syntenic regions conferring QTL for different trait may suggest sub-functionalization after duplication. Collectively, this study provides resources for marker-assisted breeding, as well as a framework for fine mapping and subsequent cloning of major genes for important traits such as plant height and flowering time in sorghum.


Subject(s)
Genotyping Techniques/methods , Quantitative Trait Loci , Sorghum/genetics , Flowers/genetics , Genome, Plant , Genotyping Techniques/standards , Inbreeding , Plant Breeding/methods , Recombination, Genetic , Sensitivity and Specificity , Sorghum/growth & development , Synteny
16.
Front Plant Sci ; 9: 16, 2018.
Article in English | MEDLINE | ID: mdl-29403522

ABSTRACT

Plant breeding programs and a wide range of plant science applications would greatly benefit from the development of in-field high throughput phenotyping technologies. In this study, a terrestrial LiDAR-based high throughput phenotyping system was developed. A 2D LiDAR was applied to scan plants from overhead in the field, and an RTK-GPS was used to provide spatial coordinates. Precise 3D models of scanned plants were reconstructed based on the LiDAR and RTK-GPS data. The ground plane of the 3D model was separated by RANSAC algorithm and a Euclidean clustering algorithm was applied to remove noise generated by weeds. After that, clean 3D surface models of cotton plants were obtained, from which three plot-level morphologic traits including canopy height, projected canopy area, and plant volume were derived. Canopy height ranging from 85th percentile to the maximum height were computed based on the histogram of the z coordinate for all measured points; projected canopy area was derived by projecting all points on a ground plane; and a Trapezoidal rule based algorithm was proposed to estimate plant volume. Results of validation experiments showed good agreement between LiDAR measurements and manual measurements for maximum canopy height, projected canopy area, and plant volume, with R2-values of 0.97, 0.97, and 0.98, respectively. The developed system was used to scan the whole field repeatedly over the period from 43 to 109 days after planting. Growth trends and growth rate curves for all three derived morphologic traits were established over the monitoring period for each cultivar. Overall, four different cultivars showed similar growth trends and growth rate patterns. Each cultivar continued to grow until ~88 days after planting, and from then on varied little. However, the actual values were cultivar specific. Correlation analysis between morphologic traits and final yield was conducted over the monitoring period. When considering each cultivar individually, the three traits showed the best correlations with final yield during the period between around 67 and 109 days after planting, with maximum R2-values of up to 0.84, 0.88, and 0.85, respectively. The developed system demonstrated relatively high throughput data collection and analysis.

17.
Sci Rep ; 8(1): 1213, 2018 01 19.
Article in English | MEDLINE | ID: mdl-29352136

ABSTRACT

Imaging sensors can extend phenotyping capability, but they require a system to handle high-volume data. The overall goal of this study was to develop and evaluate a field-based high throughput phenotyping system accommodating high-resolution imagers. The system consisted of a high-clearance tractor and sensing and electrical systems. The sensing system was based on a distributed structure, integrating environmental sensors, real-time kinematic GPS, and multiple imaging sensors including RGB-D, thermal, and hyperspectral cameras. Custom software was developed with a multilayered architecture for system control and data collection. The system was evaluated by scanning a cotton field with 23 genotypes for quantification of canopy growth and development. A data processing pipeline was developed to extract phenotypes at the canopy level, including height, width, projected leaf area, and volume from RGB-D data and temperature from thermal images. Growth rates of morphological traits were accordingly calculated. The traits had strong correlations (r = 0.54-0.74) with fiber yield and good broad sense heritability (H2 = 0.27-0.72), suggesting the potential for conducting quantitative genetic analysis and contributing to yield prediction models. The developed system is a useful tool for a wide range of breeding/genetic, agronomic/physiological, and economic studies.


Subject(s)
Gossypium , High-Throughput Screening Assays , Multimodal Imaging , Phenotype , Equipment Design , Genotype , High-Throughput Screening Assays/instrumentation , High-Throughput Screening Assays/methods , Image Processing, Computer-Assisted , Multimodal Imaging/instrumentation , Multimodal Imaging/methods , Quantitative Trait, Heritable , Reproducibility of Results
18.
J Neurol Surg B Skull Base ; 78(3): 251-255, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28593112

ABSTRACT

Objective This case series investigates management of glomus jugulare (GJ) tumors utilizing definitive and salvage Gamma Knife stereotactic radiosurgery (GKSRS). Methods A retrospective chart review was performed to collect data. Statistical analysis included patient, tumor, and treatment information. Results From 1996 to 2013, 17 patients with GJ received GKSRS. Median age was 64 years (range, 27-76). GKSRS was delivered for definitive treatment in eight (47%) and salvage in nine (53%) patients. Median tumor volume was 9.8 cm 3 (range, 2.8-42 cm 3 ). Median dose was 15 Gy (range, 13-18 Gy). Median follow-up was 123 months (range, 38-238 months). Tumor size decreased in 10 (59%), stabilized in 6 (35%), and increased in 1 patient (6%). Overall neurological deficit improved in 53%, stabilized in 41%, and worsened in 6% of patients. Overall cause-specific survival was 100%, and actuarial local control was 94%. Eighty-eight percent of patients without prior resection experienced neurologic deficit improvement, while 25% of patients with prior resection experienced neurologic improvement ( p = 0.02). Conclusion Gamma Knife radiosurgery provides effective long-term control of GJ and overall improvement or stabilization of neurological deficit in most patients. Patients with prior resection are less likely to experience improvement of neurologic deficit.

19.
Front Plant Sci ; 8: 2235, 2017.
Article in English | MEDLINE | ID: mdl-29503653

ABSTRACT

Monitoring flower development can provide useful information for production management, estimating yield and selecting specific genotypes of crops. The main goal of this study was to develop a methodology to detect and count cotton flowers, or blooms, using color images acquired by an unmanned aerial system. The aerial images were collected from two test fields in 4 days. A convolutional neural network (CNN) was designed and trained to detect cotton blooms in raw images, and their 3D locations were calculated using the dense point cloud constructed from the aerial images with the structure from motion method. The quality of the dense point cloud was analyzed and plots with poor quality were excluded from data analysis. A constrained clustering algorithm was developed to register the same bloom detected from different images based on the 3D location of the bloom. The accuracy and incompleteness of the dense point cloud were analyzed because they affected the accuracy of the 3D location of the blooms and thus the accuracy of the bloom registration result. The constrained clustering algorithm was validated using simulated data, showing good efficiency and accuracy. The bloom count from the proposed method was comparable with the number counted manually with an error of -4 to 3 blooms for the field with a single plant per plot. However, more plots were underestimated in the field with multiple plants per plot due to hidden blooms that were not captured by the aerial images. The proposed methodology provides a high-throughput method to continuously monitor the flowering progress of cotton.

20.
Front Plant Sci ; 8: 2233, 2017.
Article in English | MEDLINE | ID: mdl-29441074

ABSTRACT

Plant canopy structure can strongly affect crop functions such as yield and stress tolerance, and canopy size is an important aspect of canopy structure. Manual assessment of canopy size is laborious and imprecise, and cannot measure multi-dimensional traits such as projected leaf area and canopy volume. Field-based high throughput phenotyping systems with imaging capabilities can rapidly acquire data about plants in field conditions, making it possible to quantify and monitor plant canopy development. The goal of this study was to develop a 3D imaging approach to quantitatively analyze cotton canopy development in field conditions. A cotton field was planted with 128 plots, including four genotypes of 32 plots each. The field was scanned by GPhenoVision (a customized field-based high throughput phenotyping system) to acquire color and depth images with GPS information in 2016 covering two growth stages: canopy development, and flowering and boll development. A data processing pipeline was developed, consisting of three steps: plot point cloud reconstruction, plant canopy segmentation, and trait extraction. Plot point clouds were reconstructed using color and depth images with GPS information. In colorized point clouds, vegetation was segmented from the background using an excess-green (ExG) color filter, and cotton canopies were further separated from weeds based on height, size, and position information. Static morphological traits were extracted on each day, including univariate traits (maximum and mean canopy height and width, projected canopy area, and concave and convex volumes) and a multivariate trait (cumulative height profile). Growth rates were calculated for univariate static traits, quantifying canopy growth and development. Linear regressions were performed between the traits and fiber yield to identify the best traits and measurement time for yield prediction. The results showed that fiber yield was correlated with static traits after the canopy development stage (R2 = 0.35-0.71) and growth rates in early canopy development stages (R2 = 0.29-0.52). Multi-dimensional traits (e.g., projected canopy area and volume) outperformed one-dimensional traits, and the multivariate trait (cumulative height profile) outperformed univariate traits. The proposed approach would be useful for identification of quantitative trait loci (QTLs) controlling canopy size in genetics/genomics studies or for fiber yield prediction in breeding programs and production environments.

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