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Phosphorus-based stimuli-responsive hydrogels have potential in a wide range of applications due to their ionizable phosphorus groups, biocompatibility, and tunable swelling capacity utilizing hydrogel design parameters and external stimuli. In this study, poly(2-methacryloyloxyethyl phosphate) (PMOEP) hydrogels were synthesized via aqueous activators regenerated by electron transfer atomic transfer radical polymerization using ascorbic acid as the reducing agent. Swelling and deswelling behaviors of PMOEP hydrogels were examined in different salt solutions, pH conditions, and temperatures. The degree of swelling in salt solutions followed CaCl2 < MgCl2 < KCl < NaCl with a decrease in swelling rate at higher concentrations until reaching a saturation point. In water, the degree of swelling increased significantly around neutral pH and remained constant at basic pH values. The effects of polymerization conditions, including pH, temperature (30, 40, 50 °C), and MOEP concentration (40, 50, 60% v/v MOEP/H2O), on the hydrogel swelling behavior in various salt solutions were also investigated. PMOEP hydrogels showed a decrease in the degree of swelling as the pH was increased above the native pH of the monomer solution. Scanning electron microscopy and energy-dispersive spectroscopy were utilized to examine the microstructure and chemical composition of the dried hydrogel after salt solution swelling. Cytotoxicity testing using rat bone marrow stem cells confirmed the biocompatibility of the PMOEP hydrogels. A unique feature of this effort was evaluation of these phosphate hydrogels for use in expansion microscopy where a significant twofold enhancement in cellular expansion capacity was showcased utilizing 4T1 mouse breast cancer cells. This comprehensive study provides valuable insights into the stimuli-responsive behavior and expansion characteristics of phosphate hydrogels, highlighting their potential in diverse biomedical applications.

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[This corrects the article DOI: 10.1021/acs.jpcc.4c01994.].

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A series of steady-state and time-resolved spectroscopies were performed on a set of eight carbene-metal-amide (cMa) complexes, where M = Cu and Au, that have been used as photosensitizers for photosensitized electrocatalytic reactions. Using ps-to-ns and ns-to-ms transient absorption spectroscopies (psTA and nsTA, respectively), the excited-state kinetics from light absorption, intersystem crossing (ISC), and eventually intermolecular charge transfer were thoroughly characterized. Using time-correlated single photon counting (TCSPC) and psTA with a thermally activated delayed fluorescence (TADF) model, the variation in intersystem crossing (ISC), (S1 → T1) rates (∼3-120 × 109 s-1), and ΔEST values (73-115 meV) for these compounds were fully characterized, reflecting systematic changes to the carbene, carbazole, and metal. The psTA additionally revealed an early time relaxation (rate ∼0.2-0.8 × 1012 s-1) attributed to solvent relaxation and vibrational cooling. The nsTA experiments for a gold-based cMa complex demonstrated efficient intermolecular charge transfer from the excited cMa to an electron acceptor. Pulse radiolysis and bulk electrolysis experiments allowed us to identify the character of the transient excited states as ligand-ligand charge transfer as well as the spectroscopic signature of oxidized and reduced forms of the cMa photosensitizer.

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Generating sustainable fuel from sunlight plays an important role in meeting the energy demands of the modern age. Herein, we report two-coordinate carbene-metal-amide (cMa, M = Cu(I) and Au(I)) complexes that can be used as sensitizers to promote the light-driven reduction of water to hydrogen. The cMa complexes studied here absorb visible photons (εvis > 103 M-1 cm-1), maintain long excited-state lifetimes (τ ∼ 0.2-1 µs), and perform stable photoinduced charge transfer to a target substrate with high photoreducing potential (E+/* up to -2.33 V vs Fc+/0 based on a Rehm-Weller analysis). We pair these coinage metal complexes with a cobalt-glyoxime electrocatalyst to photocatalytically generate hydrogen and compare the performance of the copper- and gold-based cMa complexes. We also find that the two-coordinate complexes herein can perform photodriven hydrogen production from water without the addition of the cobalt-glyoxime electrocatalyst. In this "catalyst-free" system, the cMa sensitizer partially decomposes to give metal nanoparticles that catalyze water reduction. This work identifies two-coordinate coinage metal complexes as promising abundant metal, solar fuel photosensitizers that offer exceptional tunability and photoredox properties.

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Two-coordinate carbene-MI-amide (cMa, MI = Cu, Ag, Au) complexes have emerged as highly efficient luminescent materials for use in a variety of photonic applications due to their extremely fast radiative rates through thermally activated delayed fluorescence (TADF) from an interligand charge transfer (ICT) process. A series of cMa derivatives was prepared to examine the variables that affect the radiative rate, with the goal of understanding the parameters that control the radiative TADF process in these materials. We find that blue-emissive complexes with high photoluminescence efficiencies (ΦPL > 0.95) and fast radiative rates (kr = 4 × 106 s-1) can be achieved by selectively extending the π-system of the carbene and amide ligands. Of note is the role played by the increased separation between the hole and electron in the ICT excited state. Analysis of temperature-dependent luminescence data and theoretical calculations indicate that the hole-electron separation exerts a primary effect on the energy gap between the lowest-energy singlet and triplet states (ΔEST) while keeping the radiative rate for the singlet state relatively unchanged. This interpretation provides guidelines for the design of new cMa derivatives with even faster radiative rates in addition to those with slower radiative rates and thus extended excited state lifetimes.

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In response to several mass-casualty shootings in the United States, multiple legislative bodies have promoted or adopted laws that restrict the magazine capacity of firearms. The stated intent of these laws is to reduce the number of rounds a bad actor can fire in a mass-casualty situation. However, objectors argue that the laws not only are ineffective but could also cause an undue burden on the ability of law-abiding gun owners to protect themselves. Using agent-based simulation modeling, a home-invasion model including two-armed bad actors and a one-armed homeowner was created to test this hypothesis. The homeowner engaged the bad actors with different capacity magazines, and the survival rate was recorded and compared across the spectrum of capacities. This model showed that reducing the homeowner's magazine capacity resulted in an increased casualty rate for the homeowner.

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Due to the theragnostic potential of mesoporous silica nanoparticles (MSNs), these were extensively investigated as a novel approach to improve clinical outcomes. Boasting an impressive array of formulations and modifications, MSNs demonstrate significant in vivo efficacy when used to identify or treat myriad malignant diseases in preclinical models. As MSNs continue transitioning into clinical trials, a thorough understanding of the characteristics of effective MSNs is necessary. This review highlights recent discoveries and advances in MSN understanding and technology. Specific focus is given to cancer theragnostic approaches using MSNs. Characteristics of MSNs such as size, shape, and surface properties are discussed in relation to effective nanomedicine practice and projected clinical efficacy. Additionally, tumor-targeting options used with MSNs are presented with extensive discussion on active-targeting molecules. Methods for decreasing MSN toxicity, improving site-specific delivery, and controlling release of loaded molecules are further explained. Challenges facing the field and translation to clinical environments are presented alongside potential avenues for continuing investigations.

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Through a field experiment set among licensed therapists (N = 425), we found nuanced evidence of heterosexist discrimination at the entry point of mental health services for a fictitious White, presumably gay man seeking counseling. We called therapists in LGB-affirming and LGB-hostile states and left voicemails requesting services. To manipulate perceived sexual orientation, a confederate using the name "Jon" recorded one of three conditions (a) heterosexual-presenting Jon, (b) gay-presenting Jon, and (c) gay-sounding Jon. Analyzes comparing the rate of returned calls for each condition within LGB-affirming versus LGB-hostile states against our referent group, gay-presenting Jon calling mental health professionals in an LGB-affirming region, revealed a number of significant effects. Notably, being perceived as gay in LGB-hostile states significantly decreased the rate of returned calls, with the reverse being true in an LGB-affirming state. The use of "gay-sounding" voice, however, did not appreciably affect these relationships.

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Vaccination of neonatal pigs could be supportive to prevent porcine reproductive and respiratory syndrome virus (PRRSV), which is an important porcine pathogen causing worldwide welfare and health problems in pigs of different age classes. However, neonatal immunity substantially differs to adults, thus different vaccines may be required in neonateal pigs. We examined if the immunogenicity and efficacy of inactivated PRRSV (iPRRSV) vaccines in neonatal pigs could be improved with adjuvants containing oil-in water (O/W) emulsions with or without Toll-like receptor (TLR) agonists and by altering the delivery route from intramuscular (i.m.) to the skin. Three-day-old PRRSV-naïve piglets (n = 54, divided in 6 groups) received a prime vaccination and a booster vaccination four weeks later. The vaccine formulations consisted of different O/W emulsions (Montanide™ ISA28RVG (ISA28)), a squalene in water emulsion (SWE) for i.m. or a Stable Emulsion (SE) with squalene for skin vaccination) and/or a mixture of TLR1/2, 7/8 and 9 agonists (TLRa) combined with iPRRSV strain 07V063. These vaccines were delivered either i.m. (ISA28, SWE, TLRa or SWE + TLRa) or into the skin (skiSE + TLRa) with dissolving microneedle (DMN)-patches. All animals received a challenge with homologous PRRSV three weeks after booster vaccination. Specific antibodies, IFN-γ production and viremia were measured at several time-points after vaccination and/or challenge, while lung pathology was studied at necropsy. After booster vaccination, only ISA28 induced a specific antibody response while a specific T-cell IFN-γ response was generated in the SWE group, that was lower for ISA28, and absent in the other groups. This suggests that prime vaccination in neonates induced a specific immune response after booster vaccination, dependent on the emulsion formulation, but not dependent on the presence of the TLRa or delivery route. Despite the measured immune responses none of the vaccines showed any efficacy. Further research focused on the early immune response in draining lymph nodes is needed to elucidate the potential of TLR agonists in vaccines for neonatal pigs.

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Critical consciousness (CC) has been heralded as an antidote to oppression. Developed by the Brazilian educator, Paulo Freire, CC represents the process by which individuals gain awareness of societal inequities and subsequently take action to dismantle the systems and institutions that sustain them. Empirically supported instruments intended to assess this important construct have only been recently introduced to the literature and have focused specifically on racism, classism, and heterosexism. The purpose of this project was to develop a psychometrically sound measure of CC that expands assessment into sexism, cissexism (genderism/transphobia), and ableism. Two studies with a total of 569 observations provided initial reliability and validity evidence on the Contemporary Critical Consciousness Measure II (CCCMII). Results from exploratory and confirmatory factor analyses suggest that the final 37-item CCCMII provides a general index of CC as well as assesses CC associated with sexism and ableism above and beyond the general factor. Results support the internal consistency and factor structure of the measure. Expected relationships between the CCCMII and existing measures of sexism, cissexism, and ableism provide evidence for the validity of the instrument. Limitations, future directions for research, and counseling implications are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

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The framework of intersectionality is a powerful analytical tool for making sense of how interlocking systems of privilege and oppression are experienced by individuals and groups. Despite the long history of the concept, intersectionality has only recently gained attention in psychology. We conducted a content analysis to assess counseling psychology's engagement with an intersectional perspective. All articles published in the Journal of Counseling Psychology (n = 4,800) and The Counseling Psychologist (n = 1,915) from their first issues until July 2016 were reviewed to identify conceptual and empirical work focused on intersectionality. A total of 40 articles were identified and examined for themes. Limitations and future directions are discussed. (PsycINFO Database Record

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Tobacco industry marketing is a primary factor influencing cigarette smoking behavior and the cigarette pack has become an important marketing vehicle for tobacco companies. Standardized "plain" cigarette packaging is advocated as a public health policy to prevent and reduce morbidity and mortality caused by smoking by reducing youth smoking initiation and promoting cessation among smokers. Plain packaging was implemented in Australia in December 2012, and several other countries are considering doing so, but each faces foreseeable legal resistance from opponents to such measures. Tobacco companies have challenged these public health policies, citing international trade agreements and intellectual property laws. Decision-making in these court cases will hinge in part on whether the evidence indicates the public health benefits of plain packaging outweigh any potential harm to tobacco manufacturers' interests. We reviewed the available evidence in support of plain packaging, finding evidence from observational, experimental, and population-based studies. Results indicate that plain packaging can reduce positive perceptions of smoking and dissuade tobacco use. Governments deciding to implement plain cigarette packaging measures can rely on this evidence to help make a strong case that plain packaging plays an important role in the context of comprehensive smoking prevention efforts.

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INTRODUCTION: The purpose of this study is to examine the scientific program of the Canadian Association of Pediatric Surgeons (CAPS) to determine if the quality of research has improved. METHODS: CAPS abstracts from 2010 to 2013 were reviewed by two independent researchers. Presentation type, study design, and level of evidence (LOE) were recorded. All differences were adjudicated by an epidemiologist. Fisher's exact test compared results to a previous study that assessed LOE in CAPS abstracts from 2005 to 2009. RESULTS: 291 abstracts were reviewed with 53 excluded and 238 included in final analysis. Reviewers demonstrated high agreement for study design (ICC=0.767 95%CI 0.715-0.810) and LOE (ICC=0.914 95%CI 0.892-0.931). Out of 238 studies, 117 (49%) were podium and 122 (51%) posters. Number of high-quality studies increased in 2010-2013 versus 2005-2009 (n=253), specifically systematic reviews (n=15 (6%) vs. n=3 (1%) p<0.01), randomized controlled trials (n=4 (2%) vs. n=0 (0%), p=0.05), and prospective cohort studies (n=41 (17%) vs. n=26 (10%), p<0.001). Retrospective cohort is still the most common. However, the number of studies has significantly decreased (n=121 (51%) vs. n=171 (68%), p<0.001). The proportion of high-level studies (LOE 2 or better) also improved (48 (20%) vs. 24 (10%) p<0.001). CONCLUSION: The quality of research presented at CAPS has greatly improved, especially in the past five years.

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PURPOSE: The most important articles on infectious diseases (ID) pharmacotherapy published in the peer-reviewed literature in 2013, as nominated and selected by panels of pharmacists and others with ID expertise, are summarized. SUMMARY: Members of the Houston Infectious Diseases Network were asked to nominate articles published last year in prominent biomedical journals that had a major impact in the field of ID pharmacotherapy. A list of 27 nominated articles on ID-related topics in general and 26 articles specifically focused on human immunodeficiency virus (HIV) infection or acquired immunodeficiency syndrome (AIDS) was compiled. In a national online survey conducted in January 2014, members of the Society of Infectious Diseases Pharmacists (SIDP) were asked to select from the list those articles that they felt had made the greatest contributions to the field of ID pharmacotherapy. Of 168 SIDP members surveyed, 108 (64%) and 53 (32%) participated in the selection of ID- and HIV/AIDS-related articles, respectively. Summaries of the top-ranked articles in both categories are presented. CONCLUSION: Major topics explored in the top-ranked ID articles of 2013 include the use of cefepime for gram-negative infections due to AmpC or extended-spectrum ß-lactamase-producing Enterobacteriaceae, optimizing antibiotic therapy through the use of extended- or continuous-infusion regimens, the use of the oral integrase inhibitor dolutegravir to combat HIV disease, and new approaches to treatment of Clostridium difficile infection and enterococcal endocarditis.

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Patients with highly angulated neck anatomy may account for up to a fifth of all patients treated by endovascular repair. However there is evidence that these patients have worse early and long-term outcomes, including sac expansion. This review explores the evidence supporting the use of endovascular repair in the setting of severe neck angulation, with particular emphasis on new technology with devices that have expanded the anatomical criteria for endovascular aneurysm repair such as the Lombard Aorfix and Medtronic Endurant endografts.

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On June 11, 2009, Dr. Margaret Chan, Director-General of the World Health Organization (WHO), declared the first influenza pandemic of the 21st century. It was the first time in history that an influenza outbreak had been tracked in real-time from the emergence of a new strain of influenza A (H1N1) up to its spread to all continents over a period of 9 weeks. In recent years the international community has been working closely to prepare for such situations. A notable example of this cooperation occurred in response to the threat posed by the highly pathogenic avian influenza A virus (H5N1). Vaccine availability is a major challenge that will require increasing worldwide production and ensuring a widespread access. In this regard it is important to underline the fact that 70% of influenza vaccine is produced in Europe and the United States. In 2006 WHO implemented a global pandemic influenza action plan (GAP) aiming at increasing the world's production capacity for pandemic vaccine. The GAP contains three elements: (1) increased use of seasonal influenza vaccination in industrialized and developing countries (resolution WHA 56.19). (2) technology transfer. (3) development of new production technologies. Nevertheless numerous barriers still prevent people living in developing countries from rapid and fair access to pandemic influenza vaccine. Capacity for production of pandemic vaccine is limited and advanced purchase agreements between industrialized countries and vaccine manufacturers reduce potential access of developing countries to pandemic vaccine. Economic and logistic factors also limit global access to pandemic vaccine. Therefore, WHO is working with industrialized countries, pharmaceutical companies and the international community as a whole to promote global solidarity and cooperation and thus ensure distribution of pandemic vaccine in poor countries with no local production. The current pandemic situation highlights the increasing globalization of public health stakes with regard to influenza vaccination. The purpose of this presentation is to review the various challenges for production and distribution of vaccines and underline the progress that has been accomplished since 2005.

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Allergy to Hymenoptera venom (VH) effects more and more patients in France. It is manifest in two main forms, which are Loco-regional (RLR) and Systemic reactions (SR). This allergy is detectable amongst others by the techniques of histamine release (HR) and release of leucotrienes C4 (LTC4). The aim of this work has been to fix a threshold that gives differentiation of RLR ad RS by the two techniques. We found in a positive population a threshold histamine release (HR) value of 25% and a concentration of LTC4 of 600 ng/ml. These are the thresholds above which a patient would be at around 70% risk of RS. This study has a predictive value for patients who are suspected of allergy of VH or who have already had clinical reactions and risk sensitization.

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The haemolytic activity of Streptococcus equi, the cause of equine strangles, was characterized. Production of haemolysin in Todd Hewitt broth was dependent on an equine serum supplement and the logarithmic phase of growth after which activity declined sharply. RNA core also induced haemolysin production from cells harvested at the end of the logarithmic phase of growth. Haemolysis was not affected by cholesterol, was only slightly increased in reducing conditions and was completely inactivated by trypan blue, identifying the haemolytic activity as streptolysin S-like (SLS-like). Purification by hydroxyapatite and Sephacryl column chromatography yielded proteins of molecular weights of approximately 6000 and 17 000-22 000 Da with a 64-fold increase in specific activity. Low molecular weight proteins from the RNA core were still present in the purified toxin. Two non-haemolytic mutants were derived by conjugation with an Enterococcus faecalis-carrying transposon Tn916. Southern blots of HindIII digests of DNA revealed that one of the mutants contained three transposon insertions and the other just one. A lambda phage library of S. equi contained plaques whose haemolytic activity was enhanced by reducing conditions and inhibited by cholesterol, suggesting a streptolysin O-like (SLO-like) activity. However, haemolysin in culture sonicates of host E. coli in which the lambda phage insert was subcloned into plasmid (pUC18), was not affected by these conditions. Seven isolates of S. equi in medium without SLS-like inducers showed no SLO-like activity and no evidence for an SLO-like toxin could be found by immunoblotting with pneumolysin antiserum and monoclonal antibodies or by polymerase chain reaction with primers derived from sequences conserved between the SLO genes of Lancefield group A, C and G streptococci. S. equi does not appear to possess a streptolysin O but does make a streptolysin S-like toxin whose production can be interrupted at just one genetic locus.

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The 16S-23S RNA gene intergenic spacers of isolates of Streptococcus equi (n = 5), S. zooepidemicus (n = 5), S. equisimilis (n = 3) and S. dysgalactiae (n = 2) were sequenced and compared. There were distinct regions within the spacer, arranged in the order 1-9 for all S. equi and one S. zooepidemicus isolate and 1,2 and 4-9 for the remaining isolates. Region 4 was identical to the tRNA(ala) gene found in the 16S-23S intergenic spacers of other streptococci. Regions 1, 5, 6 and 7 had distinct variations, each conserved in different isolates. However, amongst the intergenic spacers there were different combinations of variant regions, suggesting a role for DNA recombination in their evolution. The intergenic spacer of all isolates of S. equi and one S. zooepidemicus isolate were almost identical. Primers derived from the variant sequences of regions 1 and 5 to 6 were used to group all S. zooepidemicus (n = 17) and S. equi (n = 5) into 1 of 8 types by polymerase chain reaction; three S. zooepidemicus isolates typed the same as S. equi. S. equi and S. zooepidemicus were clearly distinguishable from S. equisimilis and S. dysgalactiae which had shorter regions 5 and 6 and no region 7. Most homology for the group C sequences was found in previously published sequences for the 16S-23S intergenic spacers of S. anginosis, S. constellatus, S. intermedius, S. salivarius and S. agalactiae. A 75-90 nucleotide length shared with S. anginosus and S. intermedius in opposite orientations in the two main variants of region 6 supported the role for DNA recombination in the evolution of the spacer. The 16S-23S intergenic spacers indicate that S. zooepidemicus was the archetypal species for S. equi and that both are genetically more distant from S. equisimilis and S. dysgalactiae. The intergenic spacer can be used to identify specifically the group C streptococci and as an epidemiological marker for S. zooepidemicus.

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