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Abstract Duckweeds are the smallest angiosperms, possessing a simple body architecture and highest rates of biomass accumulation. They can grow near‐exponentially via clonal propagation. Understanding their reproductive biology, growth, and development is essential to unlock their potential for phytoremediation, carbon capture, and nutrition. However, there is a lack of non‐laborious and convenient methods for spatially and temporally imaging an array of duckweed plants and growth conditions in the same experiment. We developed an automated microscopy approach to record time‐lapse images of duckweed plants growing in 12‐well cell culture plates. As a proof‐of‐concept experiment, we grew duckweed on semi‐solid media with and without sucrose and monitored its effect on their growth over 3 days. Using the PlantCV toolkit, we quantified the thallus area of individual plantlets over time, and showed that L. minor grown on sucrose had an average growth rate four times higher than without sucrose. This method will serve as a blueprint to perform automated high‐throughput growth assays for studying the development patterns of duckweeds from different species, genotypes, and conditions.

Abstract Objectives To determine preference patterns for topical anesthesia in patients undergoing endoscopy pre‐coronavirus (2019 coronavirus disease [COVID‐19]) pandemic and analyze outcomes based on preference, using a decision aid format. Methods A decision aid was developed with expert and patient input. New patients presenting to subspecialty clinics over a 2‐month pre‐COVID‐19 period completed a pre‐procedure survey about their priorities, then were asked to choose between topical oxymetazoline/lidocaine spray or none. A post‐procedure outcome survey followed. Results Of 151 patients, 90.1% patients elected to have topical anesthesia. Top patient priorities were “I want the scope to be easy for the doctor” and “I want to be as comfortable as possible.” Patients who strongly wanted to avoid medication (P = .002) and bad taste (P = .003) were more likely to select no spray, whereas those who wanted to avoid pain received anesthetic (P = .011). According to the post‐procedure assessment, 95.4% of patients were satisfied or strongly satisfied their choice, and this did not correlate with anesthetic vs none. Conclusions Patient preferences are easily elicited and correlate with treatment choices. Most patients chose to have topical anesthetic and were willing to tolerate side effects; however, both patients with and without topical anesthetic were satisfied with their choices. This decision aid can be used to optimize shared decision making in the otolaryngology clinic. Given the aerosolizing potential of both spray and no spray conditions, this insight may be consequential when devising office protocols for post‐COVID‐19 practice. Level of evidence II.

Pre-meiotic anthers of monocots accumulate phased, small interfering RNAs (phasiRNAs) that are absent in many well-studied model eudicots. Here, the authors show that such 21-nt phasiRNAs are in fact present in diverse eudicot species including strawberry, in which production is triggered by miR11308.

Lettuce (Lactuca sativa) is a major crop and a member of the large, highly successful Compositae family of flowering plants. Here we present a reference assembly for the species and family. This was generated using whole-genome shotgun Illumina reads plus in vitro proximity ligation data to create large superscaffolds; it was validated genetically and superscaffolds were oriented in genetic bins ordered along nine chromosomal pseudomolecules. We identify several genomic features that may have contributed to the success of the family, including genes encoding Cycloidea-like transcription factors, kinases, enzymes involved in rubber biosynthesis and disease resistance proteins that are expanded in the genome. We characterize 21 novel microRNAs, one of which may trigger phasiRNAs from numerous kinase transcripts. We provide evidence for a whole-genome triplication event specific but basal to the Compositae. We detect 26% of the genome in triplicated regions containing 30% of all genes that are enriched for regulatory sequences and depleted for genes involved in defence.

The degradation of small RNAs in plants and animals is associated with small RNA 3' truncation and 3' uridylation and thus relies on exonucleases and nucleotidyl transferases. ARGONAUTE (AGO) proteins associate with small RNAs in vivo and are essential for not only the activities but also the stability of small RNAs. AGO1 is the microRNA (miRNA) effector in Arabidopsis, and its closest homolog, AGO10, maintains stem cell homeostasis in meristems by sequestration of miR165/6, a conserved miRNA acting through AGO1. Here, we show that SMALL RNA DEGRADING NUCLEASES (SDNs) initiate miRNA degradation by acting on AGO1-bound miRNAs to cause their 3' truncation, and the truncated species are uridylated and degraded. We report that AGO10 reduces miR165/6 accumulation by enhancing its degradation by SDN1 and SDN2 in vivo. In vitro, AGO10-bound miR165/6 is more susceptible to SDN1-mediated 3' truncation than AGO1-bound miR165/6. Thus, AGO10 promotes the degradation of miR165/6, which is contrary to the stabilizing effect of AGO1. Our work identifies a class of exonucleases responsible for miRNA 3' truncation in vivo and uncovers a mechanism of specificity determination in miRNA turnover. This work, together with previous studies on AGO10, suggests that spatially regulated miRNA degradation underlies stem cell maintenance in plants.

Volume electron microscopy, a powerful approach to generate large three-dimensional cell and tissue volumes at electron microscopy resolutions, is rapidly becoming a routine tool for understanding fundamental and applied biological questions. One of the enabling factors for its adoption has been the development of conventional fixation protocols with improved heavy metal staining. However, freeze-substitution with organic solvent-based fixation and staining has not realized the same level of benefit. Here, we report a straightforward approach including osmium tetroxide, acetone and up to 3% water substitution fluid (compatible with traditional or fast freeze-substitution protocols), warm-up and transition from organic solvent to aqueous 2% osmium tetroxide. Once fully hydrated, samples were processed in aqueous based potassium ferrocyanide, thiocarbohydrazide, osmium tetroxide, uranyl acetate and lead acetate before resin infiltration and polymerization. We observed a consistent and substantial increase in heavy metal staining across diverse and difficult-to-fix test organisms and tissue types, including plant tissues (Hordeum vulgare), nematode (Caenorhabditis elegans) and yeast (Saccharomyces cerevisiae). Our approach opens new possibilities to combine the benefits of cryo-preservation with enhanced contrast for volume electron microscopy in diverse organisms.

Colletotrichum species are globally distributed and well known as members of a destructive phytopathogenic genus, causing the anthracnose disease in a wide variety of crops and fruits. Colletotrichum sublineola is the causal agent of the anthracnose disease in sorghum, causing losses of up to 50% in yield. Here, we used PacBio sequencing combined with RNA-seq to generate a chromosome-level assembly and annotation of the Colletotrichum sublineola strain CsGL1.[Graphic: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Blood vessels are essential for maintaining tumor growth, progression, and metastasis, yet the tumor vasculature is under a constant state of remodeling. Since the tumor vasculature is an attractive therapeutic target, there is a need to predict the dynamic changes in intratumoral fluid pressure and velocity that occur across the tumor microenvironment (TME). The goal of this study was to obtain insight into perfusion anisotropy within lung tumors. To achieve this goal, we used the perfusion marker Hoechst 33342 and vascular endothelial marker CD31 to stain tumor sections from C57BL/6 mice harboring Lewis lung carcinoma tumors on their flank. Vasculature, capillary diameter, and permeability distribution were extracted at different time points along the tumor growth curve. A computational model was generated by applying a unique modeling approach based on the smeared physical fields (Kojic Transport Model, KTM). KTM predicts spatial and temporal changes in intratumoral pressure and fluid velocity within the growing tumor. Anisotropic perfusion occurs within two domains: capillary and extracellular space. Anisotropy in tumor structure causes the nonuniform distribution of pressure and fluid velocity. These results provide insights regarding local vascular distribution for optimal drug dosing and delivery to better predict distribution and duration of retention within the TME. [ABSTRACT FROM AUTHOR]

Summary: P/TGMS (Photo/thermo‐sensitive genic male sterile) lines are crucial resources for two‐line hybrid rice breeding. Previous studies revealed that slow development is a general mechanism for sterility–fertility conversion of P/TGMS in Arabidopsis. However, the difference in P/TGMS genes between rice and Arabidopsis suggests the presence of a distinct P/TGMS mechanism in rice. In this study, we isolated a novel P/TGMS line, ostms19, which shows sterility under high‐temperature conditions and fertility under low‐temperature conditions. OsTMS19 encodes a novel pentatricopeptide repeat (PPR) protein essential for pollen formation, in which a point mutation GTA(Val) to GCA(Ala) leads to ostms19 P/TGMS phenotype. It is highly expressed in the tapetum and localized to mitochondria. Under high temperature or long‐day photoperiod conditions, excessive ROS accumulation in ostms19 anthers during pollen mitosis disrupts gene expression and intine formation, causing male sterility. Conversely, under low temperature or short‐day photoperiod conditions, ROS can be effectively scavenged in anthers, resulting in fertility restoration. This indicates that ROS homeostasis is critical for fertility conversion. This relationship between ROS homeostasis and fertility conversion has also been observed in other tested rice P/TGMS lines. Therefore, we propose that ROS homeostasis is a general mechanism for the sterility–fertility conversion of rice P/TGMS lines. [ABSTRACT FROM AUTHOR]

This multi-center study examined the safety and effectiveness of cochlear implantation of children between 9 and 11 months of age. The intended impact was to support practice regarding candidacy assessment and prognostic counseling of pediatric cochlear implant candidates. Data in the clinical chart of children implanted at 9–11 months of age with Cochlear Ltd devices at five cochlear implant centers in the United States and Canada were included in analyses. The study included data from two cohorts implanted with one or two Nucleus devices during the periods of January 1, 2012–December 31, 2017 (Cohort 1, n = 83) or between January 1, 2018 and May 15, 2020 (Cohort 2, n = 50). Major adverse events (requiring another procedure/hospitalization) and minor adverse events (managed with medication alone or underwent an expected course of treatment that did not require surgery or hospitalization) out to 2 years post-implant were monitored and outcomes measured by audiometric thresholds and parent-reports on the IT-MAIS and LittlEARS questionnaires were collected. Results revealed 60 adverse events in 41 children and 227 ears implanted (26%) of which 14 major events occurred in 11 children; all were transitory and resolved. Improved hearing with cochlear implant use was shown in all outcome measures. Findings reveal that the procedure is safe for infants and that they show clear benefits of cochlear implantation including increased audibility and hearing development. [ABSTRACT FROM AUTHOR]

SUMMARY: Noncoding and coding RNAs are key regulators of plant growth, development, and stress responses. To investigate the types of transcripts accumulated during the vegetative to reproductive transition and floral development in the Coffea arabica L., we sequenced small RNA libraries from eight developmental stages, up to anthesis. We combined these data with messenger RNA and PARE sequencing of two important development stages that marks the transition of an apparent latent to a rapid growth stage. In addition, we took advantage of multiple in silico tools to characterize genomic loci producing small RNAs such as phasiRNAs, miRNAs, and tRFs. Our differential and co‐expression analysis showed that some types of small RNAs such as tRNAs, snoRNAs, snRNAs, and phasiRNAs preferentially accumulate in a stage‐specific manner. Members of the miR482/miR2118 superfamily and their 21‐nucleotide phasiRNAs originating from resistance genes show a robust co‐expression pattern that is maintained across all the evaluated developmental stages. Finally, the majority of miRNAs accumulate in a family stage‐specific manner, related to modulated hormonal responses and transcription factor expression. Significance Statement: Small RNAs in coffee floral development: unveiling stage‐specific accumulation patterns and regulatory networks. [ABSTRACT FROM AUTHOR]

'Southern hospitality' is a central pillar of tourism and culture in the southern U.S. Traditionally associated with a rural, southern style of politeness, it is unclear how this regional form of hospitality is influenced by externally-driven growth. Also, some perceive it as a romanticized myth built upon racial injustice. This study explored the meanings of southern hospitality in Charleston, South Carolina, a rapidly growing city that has become a popular tourism destination partly due to its reputation for southern hospitality. An initial research phase asked 730 U.S. travellers via survey to define southern hospitality. It was found to be associated with host kindness and food/beverage, and respondents who had visited Charleston were more likely to hold positive views towards it. A second research phase involved asking about southern hospitality in oral history interviews with 55 Charleston residents. Five underlying themes were revealed – kindness and openness, a (possibly disappearing) way of life, food and beverage, the hospitality and tourism sector, and veneer and façade. Overall, southern hospitality was seen as a genuine cultural attribute present in both the private and commercial spheres, and as a mostly positive trait that also contained some problematic elements. Theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

Recent reforms in undergraduate science education have highlighted the need for student-centered learning that challenges students to take ownership of the scientific process through conducting authentic research. As such, Undergraduate Research Experiences (UREs) have become more prevalent in higher education. However, extensive variations in the structures, durations, and contexts of UREs exist and long-term implications are not well documented. We used the Social Cognitive Career Theory to guide our exploration of student outcomes from completing a required three-semester capstone URE at a predominantly undergraduate institution located in the Midwest, United States. We sought to answer two central research questions: (1) What skills and competencies do alumni perceive to have gained from completing the URE capstone, and (2) What is the impact of the URE capstone on alumni success in the workforce and/or graduate school? We conducted in-depth, one-on-one interviews with 16 alumni who recently completed their undergraduate research capstone and who were currently in a science-based career or attending graduate school. Results indicate long-term benefits from URE capstones and are described through three primary themes: technical skill acquisition and future application, soft skill acquisition and future application, and scientific pursuits. [ABSTRACT FROM AUTHOR]

Objectives This study aimed to report household catastrophic spending on surgery and the experiences of patients and families seeking surgical care in rural Haiti.Design The study used an explanatory, sequential mixed-methods approach. We collected both quantitative and qualitative data from the participants through interviews.Setting A rural tertiary hospital (St. Boniface Hospital) in southern Haiti.Participants There were 200 adult Haitian surgical patients who entered the study. Of these, 41 were excluded due to missing variables or health expenditure outliers. The final sample included 159 participants.Primary and secondary outcome measures The primary outcomes were (1) direct and indirect payments for surgical care; (2) the rate of catastrophic health expenditure (CHE) (as defined by the Sustainable Development Goals (10% of total household expenditure) and WHO (10%, 20%, 30% and 40% of household capacity to pay)) due to surgical care; and (3) common themes across the lived experiences of households of surgical patients seeking care.Results The median household expenditure on surgery-related expenses was US$385.6, slightly more than half of per capita gross domestic product in Haiti (US$729.3). Up to 86% of households experienced CHE, as defined by the Sustainable Development Goals, due to receiving surgical care. Patients commonly paid for surgical costs through loans and donations (69.8%). The qualitative analysis revealed prominent themes related to barriers to care including the burden of initiating care-seeking, care-seeking journeys and social suffering.Conclusions CHE is common for Haitian surgical patients, and the associated care-seeking experiences are often arduous. These findings suggest that low, flat fees in non-profit hospital settings may not be sufficient to mitigate the costs of surgical care or the resulting challenges that patients experience.

A wide range of challenges continues to exist in delivering school-based agricultural education (SBAE) programs. Among the most pressing challenges are the recruitment and retention of high-quality agriculture teachers (Guffey & Young, 2020). Teacher educators and researchers in SBAE are tasked with meeting the nationwide demand for teachers, while also better understanding the status of alternatively certified agriculture teachers (Foster et al., 2020). This study explored the challenges, coping strategies, and personal resilience of first-year agriscience teachers in Florida who held a temporary teaching certificate. Using a qualitative, phenomenological approach, seven alternatively certified Florida agriculture teachers were interviewed. The personal resilience framework developed by Hoopes (2017) guided this study, as researchers examined alternatively certified teachers’ experiences and responses to challenges in their teaching. Emergent themes included prior plans to teach, overwhelming expectations, supportive networks, aspects of resilience, and feelings of motivation and inspiration. This study highlights the need for proactive professional development and support systems for first-year, alternatively certified agriculture teachers.

Perfluorosulfonic-acid (PFSA) membranes are widely used as the solid electrolyte in electrochemical devices where their main functionalities are ion (proton) conduction and gas separation in a thermomechanically stable matrix. Due to prolonged operational requirements in these devices, PFSA membranes' properties change with time due to hygrothermal aging. This paper studies the evolution of PFSA structure/property relationship changes during hygrothermal aging, including chemical changes leading to changes in ion-exchange capacity (IEC), nanostructure, water-uptake behavior, conductivity, and mechanical properties. Our findings demonstrate that with hygrothermal aging, the storage modulus increases, while IEC and water content decrease, consistent with the changes in nanostructure, that is, water- and crystalline-domain spacings inferred from small- and wide-angle X-ray scattering (SAXS/WAXS) experiments. In addition, the impact of aging is found to depend on the membrane's thermal prehistory and post-treatments, although universal correlations exist between nanostructural changes and water uptake. The findings have impact on understanding lifetime, durability, and use of these and related polymers in various technologies.

Synthetic cannabinoid use has risen at alarming rates. This case series describes 11 patients exposed to the synthetic cannabinoid, MAB-CHMINACA who presented to an emergency department with life-threatening toxicity including obtundation, severe agitation, seizures and death. All patients required sedatives for agitation, nine required endotracheal intubation, three experienced seizures, and one developed hyperthermia. One developed anoxic brain injury, rhabdomyolysis and died. A significant number were pediatric patients. The mainstay of treatment was aggressive sedation and respiratory support. Synthetic cannabinoids pose a major public health risk. Emergency physicians must be aware of their clinical presentation, diagnosis and treatment.