583 research outputs found

    Post-polymerization functionalization of poly(ethylene oxide)–poly(β-6-heptenolactone) diblock copolymers to tune properties and self-assembly

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    Copolymers were synthesized and functionalized with a variety of moieties to tune self-assembly and install drugs or fluorescent dyes. , Polyester-based amphiphilic block copolymers and their nanoassemblies are of significant interest for a wide range of applications due to the degradability of the polyester block. However, the commonly used polyesters lack functional groups on their backbones, limiting the possibilities to chemically modify these polymers. Described here are new poly(ethylene oxide) (PEO)–poly(β-6-heptenolactone) (PHEL) block copolymers having pendant alkenes at each repeat unit on the PHEL block. First, the self-assembly of these block copolymers in aqueous solution was studied and it was found that they formed solid nanoparticles and vesicles depending on the relative block lengths. Next the alkene moieties of the block copolymer were modified with either hydrophilic or hydrophobic pendant groups using thiol–ene reactions, allowing the hydrophilic mass fractions and consequently the self-assembled morphologies to be tuned, accessing both smaller nanoparticles and cylindrical assemblies. It was also demonstrated that the anti-cancer drug paclitaxel or a fluorescent rhodamine dye could be easily conjugated to the block copolymers and the self-assembly of these conjugates was explored. Overall, the results of this study demonstrate that PEO-PHEL block copolymers can serve as versatile backbones for the preparation of functional, polyester-based materials

    Magnetoacoustic Portals and the Basal Heating of the Solar Chromosphere

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    We show that inclined magnetic field lines at the boundaries of large-scale convective cells (supergranules) provide "portals" through which low-frequency ( 5 mHz) acoustic waves, which are believed to provide the dominant source of wave heating of the chromosphere. This result opens up the possibility that low-frequency magnetoacoustic waves provide a significant source of energy for balancing the radiative losses of the ambient solar chromosphere

    EFFECT OF A NITRIC OXIDE PRE-WORKOUT SUPPLEMENT ON MUSCULAR ENDURANCE

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    Introduction: Multi-ingredient dietary supplements have been developed to increase nitric oxide (NO) production, with the expectation of improving resistance training performance. Many of these supplements contain ingredients and/ or ingredient amounts that have yet to be studied for their synergy or efficacy in increasing NO production and thus, resistance training performance. Purpose of the study: A randomized crossover design was used to investigate the effect of a citrulline malate (CM) based non-stimulant nitric oxide pre-workout supplement (NOPWS) blend or placebo on Young Men’s Christian Association (YMCA) bench press performance. Applied Methodology: Thirty-minutes were provided between NOPWS or placebo ingestion and YMCA bench press assessment. Pre/post heart rate was taken following each condition. Two- and one-way repeated measures ANOVAs (α = 0.05) were run to determine the effect of each condition on heart rate (HR) and the number of repetitions performed (respectively) during the bench press test. Achieved major results: There was a significant two-way interaction between the treatment and time for HR, F(1, 20) = 6.82, p = .017. Resting HR was significantly higher during the supplement session (M = 74.67, SE = 2.54 bpm) than during the placebo session (M = 69.14, SE = 2.31 bpm), F(1, 20) = 8.19, p = .010, ηp 2 = .290. No significant difference was found between conditions for number of repetitions performed. Leads: A specific CM-containing NOPWS blend had no significant effect on a standardized assessment of upper body muscular endurance. Practical implications: These findings highlight the need for consideration of the minimum effective dosage and assimilation timing of each respective ingredient when developing or researching pre-workout supplement blends. Originality/Value: This is the first known research to study the effectiveness of this specific blend of ingredients on resistance training performance. Thus, this study provides necessary foundational knowledge for future research in this area

    Cyberinfrastructure Deployments on Public Research Clouds Enable Accessible Environmental Data Science Education

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    Modern science depends on computers, but not all scientists have access to the scale of computation they need. A digital divide separates scientists who accelerate their science using large cyberinfrastructure from those who do not, or who do not have access to the compute resources or learning opportunities to develop the skills needed. The exclusionary nature of the digital divide threatens equity and the future of innovation by leaving people out of the scientific process while over-amplifying the voices of a small group who have resources. However, there are potential solutions: recent advancements in public research cyberinfrastructure and resources developed during the open science revolution are providing tools that can help bridge this divide. These tools can enable access to fast and powerful computation with modest internet connections and personal computers. Here we contribute another resource for narrowing the digital divide: scalable virtual machines running on public cloud infrastructure. We describe the tools, infrastructure, and methods that enabled successful deployment of a reproducible and scalable cyberinfrastructure architecture for a collaborative data synthesis working group in February 2023. This platform enabled 45 scientists with varying data and compute skills to leverage 40,000 hours of compute time over a 4-day workshop. Our approach provides an open framework that can be replicated for educational and collaborative data synthesis experiences in any data- and compute-intensive discipline

    Isolation and Characterization of a Baculovirus Associated with the Insect Parasitoid Wasp, Cotesia marginiventris, or Its Host, Trichoplusia ni

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    A multiple nucleopolyhedrovirus (MNPV) was isolated from Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) larvae that had been stung by the parasitoid Cotesia marginiventris (Cresson) (Hymenoptera: Braconidae). The wild type virus was plaque purified by infecting a Heliothis subflexa (BCIRL- HsAM1) cell line and isolating several clones. The mean estimated genomic size of this virus based on PstI, BstEII, StyI, HindIII restriction profiles was estimated to be 106 ± 2.5 kbp (mean±SE). A clone designated as TnMNPV/CmBCL9 was used in bioassays against several lepidopteran pests and in comparative studies with the baculoviruses AcMNPV, AgMNPV, AfMNPV, PxMNPV and HzSNPV of Autographa califomica, Anticarsia gemmatalis, Anagrapha falcifera, Plutella xylostella, and Helicoverpa zea, respectively. Infectivity studies showed that TnMNPV/CmBCL9 was highly infectious for Heliothis subflexa and T. ni, with an LC50 value 0.07 occlusion bodies/mm2 in both species and also infectious for H. zea and Heliothis virescens with LC50 values of 0.22 and 0.27 occlusion bodies/mm2, respectively. Restriction endonuclease analysis of the isolate and selected baculoviruses revealed profiles that were very similar to AfMNPV but different from the restriction endonuclease profiles of the other baculoviruses. Hybridization studies suggest that the TnMNPV/CmBCL9 was closely related to AfMNPV and AcMNPV-HPP. Further support for this comes from a phylogenetic analysis employing a split-graphs network, comparing the polh, egt, and p10 genes from TnMNPV/CmBCL9 with those from other baculoviruses and suggests that this virus is closely related to the AcMNPV variants, AfMNPV and RoMNPV of Rachiplusia ou

    Initiating the dialogue between infant mental health and family therapy: a qualitative inquiry and recommendations

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    This qualitative study explores infant-family mental health experts' perspectives and experiences regarding the inclusion of infants in the family therapy setting. Infant socioemotional development is relational in nature and evolves in the context of both dyadic attachment relationships and broader multi-person co-parenting systems. Given this, we sought to understand why family therapy interventions involving families with infants rarely include the infant in a triangular or family systemic approach. Interviews were completed by clinical and/or research experts whose work integrates tenets of both infant mental health (IMH) and family theory and therapy. All interviewees brought at least 5 years of expertise and were actively engaged in the field. Interviewees expressed consistent beliefs that infants have a rightful and helpful place in family therapy approaches. They maintained that infants' innate social drive and communicative capacities position them to make meaningful and clinically significant contributions within family and systemic psychotherapy contexts. Noting that infants have remained on the periphery of these practices, experts advocated expansion and greater integration between IMH and family therapy, while preserving each field's distinctive identity. Experts reported that the interplay between IMH and family therapy fields has been uni-directional as family systems concepts are embedded within IMH approaches, but few IMH premises are incorporated in mainstream family therapy practices. The disconnect was attributed to multiple factors, including graduate and professional training and theoretical, clinical, research, and sociocultural barriers, which were mutually reinforcing. Experts also identified clinical gains for both infants and family members when infants were meaningfully included in family interventions. Common ground was identified between the disciplines, with a belief that relationally distressed young children and parents are best served by clinical engagement with their network of relationships. Results call for greater collaboration between disciplines to challenge existing traditions and to more fully include infants in mainstream family therapy. Recommendations for integration of family therapy and IMH in clinical, theoretical, research, training, and sociocultural domains are offered

    An exploration of parents’ preferences for foot care in juvenile idiopathic arthritis: a possible role for the discrete choice experiment

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    Background: An increased awareness of patients’ and parents’ care preferences regarding foot care is desirable from a clinical perspective as such information may be utilised to optimise care delivery. The aim of this study was to examine parents’ preferences for, and valuations of foot care and foot-related outcomes in juvenile idiopathic arthritis (JIA).<p></p> Methods: A discrete choice experiment (DCE) incorporating willingness-to-pay (WTP) questions was conducted by surveying 42 parents of children with JIA who were enrolled in a randomised-controlled trial of multidisciplinary foot care at a single UK paediatric rheumatology outpatients department. Attributes explored were: levels of pain; mobility; ability to perform activities of daily living (ADL); waiting time; referral route; and footwear. The DCE was administered at trial baseline. DCE data were analysed using a multinomial-logit-regression model to estimate preferences and relative importance of attributes of foot care. A stated-preference WTP question was presented to estimate parents’ monetary valuation of health and service improvements.<p></p> Results: Every attribute in the DCE was statistically significant (p < 0.01) except that of cost (p = 0.118), suggesting that all attributes, except cost, have an impact on parents’ preferences for foot care for their child. The magnitudes of the coefficients indicate that the strength of preference for each attribute was (in descending order): improved ability to perform ADL, reductions in foot pain, improved mobility, improved ability to wear desired footwear, multidisciplinary foot care route, and reduced waiting time. Parents’ estimated mean annual WTP for a multidisciplinary foot care service was £1,119.05.<p></p> Conclusions: In terms of foot care service provision for children with JIA, parents appear to prefer improvements in health outcomes over non-health outcomes and service process attributes. Cost was relatively less important than other attributes suggesting that it does not appear to impact on parents’ preferences.<p></p&gt

    The Hamiltonian limit of (3+1)D SU(3) lattice gauge theory on anisotropic lattices

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    The extreme anisotropic limit of Euclidean SU(3) lattice gauge theory is examined to extract the Hamiltonian limit, using standard path integral Monte Carlo (PIMC) methods. We examine the mean plaquette and string tension and compare them to results obtained within the Hamiltonian framework of Kogut and Susskind. The results are a significant improvement upon previous Hamiltonian estimates, despite the extrapolation procedure necessary to extract observables. We conclude that the PIMC method is a reliable method of obtaining results for the Hamiltonian version of the theory. Our results also clearly demonstrate the universality between the Hamiltonian and Euclidean formulations of lattice gauge theory. It is particularly important to take into account the renormalization of both the anisotropy, and the Euclidean coupling βE \beta_E , in obtaining these results.Comment: 10 pages, 11 figure

    Progressive cortical visual failure associated with occipital calcification and coeliac disease with relative preservation of the dorsal ‘action’ pathway

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    We describe the first reported case of a patient with coeliac disease and cerebral occipital calcification who shows a progressive and seemingly selective failure to recognize visual stimuli. This decline was tracked over a study period of 22 years and occurred in the absence of primary sensory or widespread intellectual impairment. Subsequent tests revealed that although the patient was unable to use shape and contour information to visually identify objects, she was nevertheless able to use this information to reach, grasp and manipulate objects under central, immediate vision. This preservation of visuo-motor control was echoed in her day-to-day ability to navigate and live at home independently. We conclude that occipital calcification following coeliac disease can lead to prominent higher visual failure that, under prescribed viewing conditions, is consistent with separable mechanisms for visual perception and action control

    Age and sex‐related variability in the presentation of generalized anxiety and depression symptoms

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    Background: Generalized anxiety and depression are extremely prevalent and debilitating. There is evidence for age and sex variability in symptoms of depression, but despite comorbidity it is unclear whether this extends to anxiety symptomatology. Studies using questionnaire sum scores typically fail to address this phenotypic complexity. Method: We conducted exploratory and confirmatory factor analyses on Generalized Anxiety Disorder (GAD‐7) and Patient Health Questionnaire (PHQ‐9) items to identify latent factors of anxiety and depression in participants from the Genetic Links to Anxiety and Depression Study (N = 35,637; 16–93 years). We assessed age‐ and sex‐related variability in latent factors and individual symptoms using multiple logistic regression. Results: Four factors of mood, worry, motor, and somatic symptoms were identified (comparative fit index [CFI] = 0.99, Tucker–Lewis Index [TLI] = 0.99, root mean square error of approximation [RMSEA] = 0.07, standardized root mean square residuals [SRMR] = 0.04). Symptoms of irritability (odds ratio [OR] = 0.81) were most strongly associated with younger age, and sleep change (OR = 1.14) with older age. Males were more likely to report mood and motor symptoms (p < .001) and females to report somatic symptoms (p < .001). Conclusion: Significant age and sex variability suggest that classic diagnostic criteria reflect the presentation most commonly seen in younger males. This study provides avenues for diagnostic adaptation and factor‐specific interventions
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