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A matrigel-free method to generate matured human cerebral organoids using 3D-Printed microwell arrays

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Bioactive Materials 2021年第4期6卷 1130-1139页

作者： Cheng Chen Venkatakrishnan Rengarajan Andrew Kjar Yu Huang Department of Biological Engineering Utah State UniversityLoganUT84322USA

The current methods of generating human cerebral organoids rely excessively on the use of Matrigel or other external extracellular matrices(ECM)for cell micro-environmental *** embedding is problematic for long-term culture and clinical applications due to high inconsistency and other *** this study,we developed a novel microwell culture platform based on 3D *** platform,without using Matrigel or external signaling molecules(i.e.,SMAD and Wnt inhibitors),successfully generated matured human cerebral organoids with robust formation of high-level features(i.e.,wrinkling/folding,lumens,neuronal layers).The formation and timing were comparable or superior to the current Matrigel methods,yet with improved *** effect of microwell geometries(curvature and resolution)and coating materials(i.e.,mPEG,Lipidure,BSA)was studied,showing that mPEG outperformed all other coating materials,while curved-bottom microwells outperformed flat-bottom *** addition,high-resolution printing outperformed low-resolution printing by creating faithful,isotropically-shaped *** trend of these effects was consistent across all developmental characteristics,including EB formation efficiency and sphericity,organoid size,wrinkling index,lumen size and thickness,and neuronal layer ***,the microwell device that was mPEG-coated,high-resolution printed,and bottom curved demonstrated the highest efficacy in promoting organoid *** platform provided a promising strategy for generating uniform and mature human cerebral organoids as an alternative to Matrigel/ECM-embedding methods.

关键词： Cortical wrinkling Cortical folding 3D culture Biomanufacturing Embryoid body spheroid Microfabrication

Extension of emission expectation maximization lookalike algorithms to Bayesian algorithms

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Visual Computing for Industry,Biomedicine,and Art 2019年第1期2卷 119-128页

作者： Gengsheng L.Zeng Ya Li Department of Engineering Utah Valley University800 W University ParkwayOremUT 84058USA Department of Radiology and Imaging Sciences University of Utah729 Arapeen DriveSalt Lake CityUT 84108USA Department of Mathematics Utah Valley University800 W University ParkwayOremUT 84058USA

We recently developed a family of image reconstruction algorithms that look like the emission maximum-likelihood expectation-maximization(ML-EM)*** this study,we extend these algorithms to Bayesian *** family of emission-EM-lookalike algorithms utilizes a multiplicative update *** extension of these algorithms to Bayesian algorithms is achieved by introducing a new simple factor,which contains the Bayesian *** of the extended algorithms can be applied to emission tomography and another to transmission *** simulations are performed and compared with the corresponding un-extended *** total-variation norm is employed as the Bayesian constraint in the computer *** newly developed algorithms demonstrate a stable performance.A simple Bayesian algorithm can be derived for any noise variance *** proposed algorithms have properties such as multiplicative updating,non-negativity,faster convergence rates for bright objects,and ease of *** algorithms are inspired by Green’s one-steplate *** written in additive-update form,Green’s algorithm has a step size determined by the future image value,which is an undesirable feature that our algorithms do not have.

关键词： Image reconstruction Tomography Iterative reconstruction algorithm

Trends in the management of anorectal melanoma:A multiinstitutional retrospective study and review of the world literature

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World Journal of Gastroenterology 2021年第3期27卷 267-280页

作者： Josh Bleicher Jessica N Cohan Lyen C Huang William Peche T Bartley Pickron Courtney L Scaife Tawnya L Bowles John R Hyngstrom Elliot A Asare Department of Surgery Huntsman Cancer Institute at the University of UtahSalt Lake CityUT 84114United States Department of Surgery George E Wahlen Department of Veterans Affairs Medical CenterSalt Lake CityUT 84114United States Department of Surgery Intermountain Medical CenterMurrayUT 84107United States

BACKGROUND Anorectal melanoma(ARM)is a rare disease with a poor *** on optimal treatment is limited and surgical management varies *** hypothesized that the frequency of abdominoperineal resection used as primary treatment of ARM has decreased over the past several *** To update our understanding of outcomes for patients with ARM and analyze management trends around the *** This is a multi-institutional,retrospective study of patients treated for ARM at 7 *** included both large,academic,tertiary care centers and smaller,general community *** prospectively maintained institutional tumor registries,we identified 24 patients diagnosed with ARM between January 2000 and May *** analyzed factors prognostic for recurrence and *** then used Cox regression to measure overall survival(OS)and melanoma-specific *** also performed a literature review to assess trends in surgical management and *** Of the 24 patients diagnosed with ARM,12(50.0%)had local,8(33.3%)regional,and 4(16.7%)distant disease at *** time to recurrence was 10.4 mo[interquartile range(IQR)7.5-17.2]with only 2 patients(9.3%)not developing recurrence following surgical *** OS was 18.8 mo(IQR 13.5-33.9).One patient is still alive without recurrence at 21.4 mo from diagnosis;no other patient survived 5 *** surgical management with abdominoperineal resection(APR)vs wide excision(WE)did not lead to differences in OS[hazard ratio=1.4(95%CI:0.3-6.8)].Review of the literature revealed geographic differences in surgical management of ARM,with increased use of WE in the United States and Europe over time and more frequent use of APR in Asia and *** was no significant improvement in survival over *** There is wide variation in the management of ARM and survival outcomes remain poor regardless of *** management should aim to minimize morbidity.

关键词： Melanoma Anorectal melanoma Literature review Melanoma surgery Surgical oncology Colorectal surgery

Chemical Versus Thermal Folding of Graphene Edges

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Nano Research 2011年第12期4卷 1242-1247页

作者： Ninghai Su Miao Liu Feng Liu Department of Materials Science and Engineering University of Utahi Salt Lake City UT 84112 USA

Using molecular dynamics （MD） simulations, we have investigated the kinetics of the graphene edge folding process. The lower limit of the energy barrier is found to be -380 meV/A （or about 800 meV per edge atom） and -50 meV/A （or about 120 meV per edge atom） for folding the edges of intrinsic clean single-layer graphene （SLG） and double-layer graphene （DLG）, respectively. However, the edge folding barriers can be substantially reduced by imbalanced chemical adsorption, such as of H atoms, on the two sides of graphene along the edges. Our studies indicate that thermal folding is not feasible at room temperature （RT） for clean SLG and DLG edges and is feasible at high temperature only for DLG edges, whereas chemical folding （with adsorbates） of both SLG and DLG edges can be spontaneous at RT. These findings suggest that the folded edge structures of suspended graphene observed in some experiments are possibly due to the presence of adsorbates at the edges.

关键词： Adsorption graphene kinetics molecular dynamics

Use of Hi-resolution data for evaluating accuracy of traffic volume counts collected by microwave sensors

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第5期4卷 423-435页

作者： David K.Chang Mitsuru Saito Grant G.Schultz Dennis L.Eggett Hales Engineering LCC LehiUT 84043USA Department of Civil&Environmental Engineering Brigham Young UniversityProvoUT 84602USA Department of Statistics Brigham Young UniversityProvoUT 84602USA

Over the past few years, the utah Department of Transportation has developed the signal performance metrics （SPMs） system to evaluate the performance of signalized in- tersections dynamically. This system currently provides data summaries for several per- formance measures, one of them being turning movement counts collected by microwave sensors. As this system became public, there was a need to evaluate the accuracy of the data placed on the SPMs. A large-scale data collection was carried out to meet this need. Vehicles in the Hi-resolution data from microwave sensors were matched with the vehicles by ground-truth volume count data. Matching vehicles from the microwave sensor data and the ground-truth data manually collected required significant effort, A spreadsheet- based data analysis procedure was developed to carry out the task. A mixed model analysis of variance was used to analyze the effects of the factors considered on turning volume count accuracy. The analysis found that approach volume level and number of approach lanes would have significant effect on the accuracy of turning volume counts but the location of the sensors did not significantly affect the accuracy of turning volume counts. In addition, it was found that the location of lanes in relation to the sensor did not significantly affect the accuracy of lane-by-lane volume counts. This indicated that accu- racy analysis could be performed by using total approach volumes without comparing specific turning counts, that is, left-turn, through and right-turn movements. In general, the accuracy of approach volume counts collected by microwave sensors were within the margin of error that traffic engineers could accept. The procedure taken to perform the analysis and a summary of accuracy of volume counts for the factor combinations considered are presented in this paper.

关键词： Traffic volume Microwave Signal Performance Accuracy Mixed model analysis of variance

Niche differentiation among facultative filter feeders: Insights from invasive Ponto-Caspian mysids

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Current Zoology 2024年第4期70卷 513-521页

作者： Péter Borza Varsha Rani Csaba F.Vada Institute of Aquatic Ecology Centre for Ecological ResearchKarolina ut 29.1113 BudapestHungary Doctoral School of Biology Institute of BiologyEotvos Lorand UniversityPazmany Péter sétany 1/C1117 BudapestHungary

The degree of dietary specialization has a fundamental impact on the ecological function and interactions of suspension *** niche differentiation by food particle size is common among obligate suspension feeders,its role is not evident in facultative *** this study,we aimed at providing new insights on the matter by focusing on sympatric mysid *** mysids use different mechanisms for raptorial and filter-feeding,they represent a more adequate model system than for example,the more extensively studied *** made morpholog-ical measurements on the 4 coexisting invasive Ponto-Caspian mysid species to determine the areas and mesh sizes of their *** also quantified their clearance rates on the microalga Cryptomonas *** a laboratory experiment to reveal how morphological differences manifest in their overall filtering *** found relatively small but consistent differences in the primary filter area among the species,indicating that morphological constraints due to the enclosed position of the setae might limit the possibility for *** primary filter mesh sizes were small in all 4 species(0.69-2.73μm)with moderate but consistent intraspecific differences,suggesting that the benefit of being able to capture small particles might outweigh the pressure for *** observed clearance rates were in accordance with the morphological characteristics of the species,highlighting that auxiliary filters(present in one of the species,Limnomysis benedeni)are needed to increase filtering capacity *** study confirmed that food particle size can contribute to the niche differentiation of facultative filter feeders,but also indicated that they can tolerate a higher overlap than obligate *** observed differences were related to the habitat preferences and predatory potentials of the species,suggesting that complementarity among the different niche axes might further facilitate theircoexistence.

关键词： clearance rate coexistence filter area filtermesh size.

Barriers to advancing nanotechnology to better improve and translate nanomedicines

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Frontiers of Chemical Science and Engineering 2014年第3期8卷 265-275页

作者： Yuwei WANG David W. Grainger Department of Pharmaceutics and Pharmaceutical Chemistry University of Utah Salt Lake City UT 84112-5820 USA

Engineered nanomaterials and nanotechnolo- gies promise many benefits to enhance both in vitro and in vivo performance. This is now manifest in the increasing number of reported biomedical products under develop- ment and testing that contain nanotechnologies as their distinguishing performance--enhancing components. In many cases, nano-sized materials are selected to provide a specific functional aspect that contributes to improved medical performance, either in vitro or in vivo. Nanopar- ticles are most commonly exploited in diverse roles in topical lotions and creams, solubilization aids, for in vitro and in vivo diagnostic and targeting agents in nanomedi- cines and theranostics. Despite fundamental scientific excitement and many claims to nanotechnology-based improvements in new biomedical applications, several fundamental and long-standing challenges remain to be addressed using nanomedicines to make clinically important progress. This review addresses several issues that must be fairly and objectively reported and then overcome to provide truly credible performance for nanomedicines.

关键词： nanotechnology nanomedicine drug delivery therapeutic targeted delivery

The hamster egg penetration test may decrease intracytoplasmic sperm injection utilization while maintaining high conventional fertilization rates

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Asian Journal of Andrology 2021年第1期23卷 11-15页

作者： Yetunde Ibrahim Brett Einerson Douglas T Carrell Benjamin R Emery Erica Johnstone Division of Reproductive Endocrinology and Infertility Department of Obstetrics and GynecologyUniversity of UtahSchool of MedicineSalt Lake CityUT 84132USA Division of Maternal-Fetal Medicine Department of Obstetrics and GynecologyUniversity of UtahSchool of MedicineSalt Lake CityUT 84132USA Division of Urology Department of SurgeryUniversity of UtahSchool of MedicineSalt Lake CityUT 84132USA Department of Human Genetics University of UtahSchool of MedicineSalt Lake CityUT 84132USA

This was a cohort study of in vitro fertilization(IVF)subjects at the University of utah,Salt Lake City(ut,USA)utilizing partner *** where both the hamster egg penetration test(HEPT)and semen analysis were performed within 2 years prior to IVF cycles were stratified into four groups based on a normal or an abnormal HEPT and *** mean conventional and intracytoplasmic sperm injection(ICSI)fertilization rates were calculated in each *** performed a univariate analysis on the primary outcome comparing clinically interesting *** performed a cost-effectiveness analysis of a policy of HEPT versus universal ICSI in couples with an abnormal *** patients with a normal HEPT,there was no difference in the mean conventional fertilization rates between those with a normal and an abnormal *** was no difference in the mean conventional fertilization rates between subjects with a normal morphology without a hamster test and those with a normal HEPT without a morphology *** 1000 simulated cycles with an abnormal morphology,a policy of HEPT was cost saving compared to universal ICSI,yet produced similar fertilization *** HEPT is similar to the World Health Organization edition 5(WHO-5)morphology in predicting successful conventional fertilization while allowing decreased utilization of ICSI.A policy of HEPT for males with abnormal morphology saves cost in selecting couples for a fertilization method.

关键词： conventional fertilization hamster egg penetration test intracytoplasmic sperm injection semen analysis sperm penetration assay

Impact of COVID-19-related lifestyle changes on diabetic macular edema

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 97-106页

作者： Bryce P.Johnson Yu-Guang He Zachary M.Robertson Angeline Wang Rafael L.Ufret-Vincenty Department of Ophthalmology UT Southwestern Medical CenterDallasTexas 75390-9057USA

AIM:To assess diabetic macular edema(DME)progression during the early phases of the COVID-19 pandemic,when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions,particularly those requiring frequent office ***:This is a multicenter retrospective chart review of 370 patients(724 eyes)with an established diagnosis of DME seen on 3 separate visits between January 2019 and July *** 1 was January 2019 to February 2020(considered pre-COVID-19),period 2 was March 2020 to December 2020(considered the height of the pandemic;highest level of pandemic-related clinical and societal regulations)and period 3 was January 2021 to July 2021(re-adjustment to the new“pandemic norms”).Main outcome measures included visual acuity,body mass index(BMI),blood pressure(BP),hemoglobin A1c(HbA1c),macular thickness,patient adherence to scheduled ophthalmology visits,and DME treatment(s)received at each *** facilitate measurement of macular thickness,each macula was divided into 9 Early Treatment Diabetic Retinopathy Study(ETDRS)-defined macular sectors as measured by OCT ***:There was no change of BMI,systolic BP,and diastolic BP between any of the time ***1c showed a very small increase from period 1(7.6%)to period 2(7.8%,P=0.015)and decreased back to 7.6%at period 3(P=0.12).Macular thickness decreased for 100%of macular *** central macular thickness decreased across all 3 periods from 329.5 to 316.6μm(P=0.0045).After analysis of multiple variables including HbA1c,BMI,adherence to scheduled appointments,different clinic centers,and treatment interventions,there was no easily identifiable subgroup of patients that experienced the increase in ***:DME doesn’t worsen during the COVID-19 pandemic,instead sustaining a very small but statistically significant *** identifying a mechanism behind our findings is beyond the scope of this study,potential explanat

关键词： COVID-19 diabetic macular edema diabetic retinopathy optical coherence tomography