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Simultaneous Nitrification and Denitrification (SND) is a promising process for biological nitrogen removal. Compared to conventional nitrogen removal processes, SND is cost-effective due to the decreased structural footprint and low oxygen and energy requirements. This critical review summarizes the current knowledge on SND related to fundamentals, mechanisms, and influence factors. The creation of stable aerobic and anoxic conditions within the flocs, as well as the optimization of dissolved oxygen (DO), are the most significant challenges in SND. Innovative reactor configurations coupled with diversified microbial communities have achieved significant carbon and nitrogen reduction from wastewater. In addition, the review also presents the recent advances in SND for removing micropollutants. The micropollutants are exposed to various enzymes due to the microaerobic and diverse redox conditions present in the SND system, which would eventually enhance biotransformation. This review presents SND as a potential biological treatment process for carbon, nitrogen, and micropollutant removal from wastewater.
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Desnitrificação , Nitrificação , Águas Residuárias , Nitrogênio/metabolismo , Reatores Biológicos , Oxigênio , Carbono/metabolismo , Eliminação de Resíduos LíquidosRESUMO
This article presents in four parts various understandings of the deep roots of the current climate emergency, some thoughts about alternative transitional paths forward, and the ways the discipline of psychology might be relevant. In Section two, we explore environmental and ontological critiques and analyses that developed in the academic world in the 1990s after the 500th anniversary of the arrival of Columbus in the Americas. In Section three, we analyze the recent emergence of new materialisms and their connections to indigenous relational ontologies and practices in what has been called "the ontological turn" or "the decolonial turn." In Section four, we trace the effects of coloniality in education. In Section five, we explore approaches to alternative world visions, new educational projects, the possible role of the discipline of psychology in transition discourses, and the urgency of the present moment.
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Escolaridade , Humanos , Estados UnidosRESUMO
Protein crystal production is a major bottleneck in the structural characterization of proteins. To advance beyond large-scale screening, rational strategies for protein crystallization are crucial. Understanding how chemical anisotropy (or patchiness) of the protein surface, due to the variety of amino-acid side chains in contact with solvent, contributes to protein-protein contact formation in the crystal lattice is a major obstacle to predicting and optimizing crystallization. The relative scarcity of sophisticated theoretical models that include sufficient detail to link collective behavior, captured in protein phase diagrams, and molecular-level details, determined from high-resolution structural information, is a further barrier. Here, we present two crystal structures for the P23T + R36S mutant of γD-crystallin, each with opposite solubility behavior: one melts when heated, the other when cooled. When combined with the protein phase diagram and a tailored patchy particle model, we show that a single temperature-dependent interaction is sufficient to stabilize the inverted solubility crystal. This contact, at the P23T substitution site, relates to a genetic cataract and reveals at a molecular level the origin of the lowered and retrograde solubility of the protein. Our results show that the approach employed here may present a productive strategy for the rationalization of protein crystallization.
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Proteínas Mutantes/química , Temperatura , gama-Cristalinas/química , Humanos , Modelos Moleculares , SolubilidadeRESUMO
Polygyny is cross-culturally common and a topic of considerable academic and policy interest, often deemed a harmful cultural practice serving the interests of men contrary to those of women and children. Supporting this view, large-scale studies of national African demographic surveys consistently demonstrate that poor child health outcomes are concentrated in polygynous households. Negative population-level associations between polygyny and well-being have also been reported, consistent with the hypothesis that modern transitions to socially imposed monogamy are driven by cultural group selection. We challenge the consensus view that polygyny is harmful, drawing on multilevel data from 56 ethnically diverse Tanzanian villages. We first demonstrate the vulnerability of aggregated data to confounding between ecological and individual determinants of health; while across villages polygyny is associated with poor child health and low food security, such relationships are absent or reversed within villages, particularly when children and fathers are coresident. We then provide data indicating that the costs of sharing a husband are offset by greater wealth (land and livestock) of polygynous households. These results are consistent with models of polygyny based on female choice. Finally, we show that village-level negative associations between polygyny prevalence, food security, and child health are fully accounted for by underlying differences in ecological vulnerability (rainfall) and socioeconomic marginalization (access to education). We highlight the need for improved, culturally sensitive measurement tools and appropriate scales of analysis in studies of polygyny and other purportedly harmful practices and discuss the relevance of our results to theoretical accounts of marriage and contemporary population policy.
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Saúde da Criança/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Casamento/estatística & dados numéricos , Antropometria , Características Culturais , Feminino , Humanos , Funções Verossimilhança , Masculino , Análise de Componente Principal , Chuva , Análise de Regressão , Fatores Socioeconômicos , TanzâniaRESUMO
Background Nurse Practitioner-Led Clinics are a new model of primary healthcare in Ontario. Nurse Practitioner-Led Clinics are distinctive in that nurse practitioners are the primary care providers working with an interprofessional team. There have been no evaluations of the quality of care within the Nurse Practitioner-Led Clinic model. Purpose Evaluation of the Nurse Practitioner-Led Clinic model, specifically for complex clinical presentations, will provide insights that may be used to inform improvements to the delivery of care in the Nurse Practitioner-Led Clinics. The aim of this study was to evaluate the extent to which diabetes care was complete and to determine the impact of organizational tools, including electronic medical record tracking, diabetes care template, and referral to community programs, on the completeness of care for patients with diabetes and multimorbidity at Nurse Practitioner-Led Clinics. Methods An audit of 30 charts was conducted at five different Nurse Practitioner-Led Clinics (n = 150) for patients with diabetes and at least one other chronic condition. Indicators included patient and organizational characteristics as well as diabetes care items taken from diabetes clinical guidelines. Results Overall, care for patients with diabetes and multimorbidity in Nurse Practitioner-Led Clinics was complete. However, there were no significant associations between patient or organizational characteristics and the extent to which diabetes care was complete.
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Instituições de Assistência Ambulatorial/organização & administração , Complicações do Diabetes , Diabetes Mellitus/enfermagem , Profissionais de Enfermagem , Relações Enfermeiro-Paciente , Qualidade da Assistência à Saúde , Feminino , Humanos , Masculino , OntárioRESUMO
Community psychology's history has traditionally been described within the context of U.S. history, silencing contributions from people of color from the Americas, Asia, the Pacific Islands, and Africa. In a MA/PhD specialization in Community Psychology, Liberation Psychology, Indigenous Psychologies, and Ecopsychology at Pacifica Graduate Institute, we are attempting to steer into critical dialogues about modernity, coloniality, and decoloniality, closely examining our curriculum and pedagogy, including our approaches to fieldwork and research. Turning to Indigenous psychologists, decolonial and critical race theorists, and cultural workers within the U.S. and from the Global South, we are attempting to challenge coloniality in the social sciences, community psychology, and in our own thinking and teaching to unmask hegemonic assumptions and open space for decolonial theory and practice. In this paper, we explore ways in which we are working with our graduate students and faculty to co-construct a decolonial curriculum that integrates decoloniality so that knowledges from historically silenced locations, as well as anti-racist and other decolonial praxes can co-exist and thrive.
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Colonialismo , Psicologia Social/educação , Ensino , Cultura , Currículo , Justiça Social , Estados UnidosRESUMO
OBJECTIVES: The importance of fathers in ensuring child health in rural developing populations is questioned by anthropologists and population health scientists. Existing literature focuses on paternal death and child mortality. A relative lack of studies consider alternative forms of father absence and/or more subtle health outcomes. Here we determine the frequency and form of father absence in northern Tanzania, and its relationship to household food security, wealth, and child anthropometric status. METHODS: We conducted a cross-sectional survey of 3136 children under 5 years of age from 56 villages. Using multilevel regression we contrast children residing with both parents to those that (i) have experienced paternal death, (ii) reside with their mother but not their living father and (iii) are fostered apart from both living parents. RESULTS: Of the total, 3.5% of children had experienced paternal death. Thirteen percent resided with their mother but away from their living father. Supporting data indicate such cases primarily reflect parental divorce/separation, extra-marital birth, or polygynous fathers residing with an alternative cowife. Paternal death and residing apart from one's living father was associated with lower food security and/or relative poverty and there is suggestive evidence that children in such circumstances achieve lower height-for-age. Six percent of children were fostered, usually with grandparents, and were comparable to children residing with both parents in terms of household food security, wealth, and anthropometric status. CONCLUSION: Our results highlight diversity in the form and consequences of father absence. We discuss limitations of the current study and wider literature on fatherhood and make suggestions for future research.
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Saúde da Criança , Características da Família , Pai , Abastecimento de Alimentos , Pobreza , Antropometria , Estudos Transversais , Cuidados no Lar de Adoção/estatística & dados numéricos , População Rural/estatística & dados numéricos , TanzâniaRESUMO
EXECUTIVE SUMMARY: Shifting healthcare market forces and regulation have exerted near-constant pressure on U.S. academic health centers (AHCs) attempting to successfully execute their traditional tripartite mission. A governance structure and organizational alignment that works well under one set of conditions is rarely optimal when conditions change. Thus, the degree and type of alignment of an AHC's clinical, educational, and faculty practice organizations have changed regularly within the sector, typically landing near one end or the other on a continuum from fully aligned with centralized governance to largely independent with separate governance. The authors examine the case of Georgia Regents University and Health System in this context. In step with industry trends, the institution's governance structure swung from fully aligned/centralized governance in the early 1990s to essentially separate and decentralized by 2000. In 2010, the Georgia Regents University organizations achieved rapid realignment by creating a governance structure of sufficient strength and flexibility to absorb and adjust to continuing external upheaval. The hospitals, clinics, and physician-faculty practice group were combined into one integrated health system, then aligned with the university to form the state's only public AHC under aligned, but distinct, corporate and management structures. The years since reorganization have seen significant growth in patient volumes and complexity, improved service quality, and enhanced faculty physician satisfaction, while also significantly increasing economic contributions from the health system to the academic mission. This case study offers observations and lessons learned that may be useful to other higher education institutions considering reorganization.
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Atenção à Saúde/organização & administração , Universidades/organização & administração , Seguimentos , HumanosRESUMO
The ability to control the self-assembly of biological molecules to form defined structures, with a high degree of predictability is a central aim for soft matter science and synthetic biology. Several examples of this are known for synthetic systems, such as anisotropic colloids. However, for biomacromolecules, such as proteins, success has been more limited, since aeolotopic (or anisotropic) interactions between protein molecules are not easily predicted. We have created three double mutants of human γD-crystallin for which the phase diagrams for singly mutated proteins can be used to predict the behavior of the double mutants. These proteins provide a robust mechanism to examine the kinetic and thermodynamic properties of proteins in which competing interactions exist due to the anisotropic or patchy nature of the protein surface.
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Agregados Proteicos , gama-Cristalinas/química , gama-Cristalinas/genética , Cristalização , Humanos , Cinética , Modelos Moleculares , Mutação , Transição de Fase , Mapas de Interação de Proteínas , Solubilidade , Termodinâmica , gama-Cristalinas/metabolismo , gama-Cristalinas/ultraestruturaAssuntos
Uso do Telefone Celular , Telefone Celular , Tocologia , Feminino , Humanos , Parto , GravidezRESUMO
OBJECTIVE: The left ventricle (LV) is routinely assessed with cardiac magnetic resonance imaging (MRI) by using short-axis orientation; it remains unclear whether the right ventricle (RV) can also be adequately assessed in this orientation or whether dedicated axial orientation is required. We used phase-contrast (PC) flow measurements in the main pulmonary artery (MPA) and the ascending aorta (Aorta) as nonvolumetric standard of reference and compared RV and LV volumes in short-axis and axial orientations. METHODS: A retrospective analysis identified 30 patients with cardiac MRI data sets. Patients underwent MRI (1.5 T or 3 T), with retrospectively gated cine steady-state free-precession in axial and short-axis orientations. PC flow analyses of MPA and Aorta were used as the reference measure of RV and LV output. RESULTS: There was a high linear correlation between MPA-PC flow and RV-stroke volume (SV) short axis (r = 0.9) and RV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 1.4 mL for RV axial and -2.3 mL for RV-short-axis vs MPA-PC flow. There was a high linear correlation between Aorta-PC flow and LV-SV short-axis (r = 0.9) and LV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 4.8 m for LV short axis and 7.0 mL for LV axial vs Aorta-PC flow. There was no significant difference (P = .6) between short-axis-LV SV and short-axis-RV SV. CONCLUSION: No significant impact of the slice acquisition orientation for determination of RV and LV stroke volumes was found. Therefore, cardiac magnetic resonance workflow does not need to be extended by an axial data set for patients without complex cardiac disease for assessment of biventricular function and volumes.
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Aorta/fisiopatologia , Cardiopatias/diagnóstico , Cardiopatias/fisiopatologia , Ventrículos do Coração/fisiopatologia , Imagem Cinética por Ressonância Magnética/métodos , Artéria Pulmonar/fisiopatologia , Adulto , Idoso , Cardiopatias/patologia , Ventrículos do Coração/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda , Função Ventricular Direita , Adulto JovemRESUMO
The present study investigated the biodegradation of three iodinated X-ray contrast media (ICM), namely, iopamidol, iohexol, and iopromide, in simultaneous nitrification-denitrification (SND) system maintained in a sequencing batch reactor (SBR). The results showed that variable aeration patterns (anoxic-aerobic-anoxic) and micro-aerobic condition were most effective in the biotransformation of ICM while achieving organic carbon and nitrogen removal. The highest removal efficiencies of iopamidol, iohexol, and iopromide were 48.24%, 47.75%, and 57.46%, respectively, in micro-aerobic condition. Iopamidol was highly resistant to biodegradation and possessed the lowest Kbio value, followed by iohexol and iopromide, regardless of operating conditions. The removal of iopamidol and iopromide was affected by the inhibition of nitrifiers. The transformation products after hydroxylation, dehydrogenation, and deiodination of ICM were detected in the treated effluent. Due to the addition of ICM, the abundance of denitrifier genera Rhodobacter and Unclassified Comamonadaceae increased, and the abundance of class TM7-3 decreased. The presence of ICM affected the microbial dynamics, and the diversity of microbes in SND resulted in improving the biodegradability of the compounds.
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Meios de Contraste , Nitrificação , Desnitrificação , Iohexol , Iopamidol , Raios X , Nitrogênio , Reatores Biológicos , EsgotosRESUMO
OBJECTIVE: To compare the mechanical behaviors of 2 locked (parallel and diverging screws) and 1 nonlocked (NL) version of triple pelvic osteotomy (TPO) plate/screw fixation. STUDY DESIGN: In vitro biomechanical evaluation. ANIMALS: Cadaveric canine hemipelves. METHODS: Comparison 1-NL screws 20° TPO (NL-20) construct versus locked parallel (LP) screws 20° TPO (LP-20) construct (n = 7). Comparison 2-LP-20 construct versus locked diverging (LD) screws 20° TPO (LD-20) construct (n = 6). Condition 1-Nondestructive loading to determine stiffness. Condition 2-Cyclic loading to determine stiffness, screw loosening, and osteotomy gap displacement. Condition 3-Load to failure (yield load, yield displacement, maximum load, load to failure, failure mode). RESULTS: Stiffness was not significantly different for NL-20 versus LP-20 constructs (P = .48) or for LP-20 versus LD-20 constructs (P = .83). Screw loosening was significantly more frequent for NL-20 versus LP-20 (P = .01) and for LD-20 versus LP-20 constructs (P = .02). The relative risk for screw loosening with NL-20 constructs versus LP-20 constructs was 1.4 (95% CI: 1.1-1.8). The relative risk for screw loosening with LD-20 versus LP-20 was 1.6 (95% CI: 1.1-2.2). Yield load was significantly greater for LP-20 versus NL-20 and LD-20 constructs (P = .04, P = .03), respectively. CONCLUSIONS: No TPO constructs tested maintained complete integrity after cyclic loading; however, screw loosening was significantly reduced and yield loads were significantly larger for LP-20 plate/screw constructs.
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Placas Ósseas/veterinária , Parafusos Ósseos/veterinária , Cães , Ílio , Osteotomia/veterinária , Animais , Cadáver , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Osteotomia/métodos , Estresse MecânicoRESUMO
An anoxic-aerobic-anoxic process was established to achieve simultaneous removal of organic carbon and nitrogen from wastewater in a sequencing batch reactor. The optimum conditions were attained at a DO of 1.5 mg/L with 1 h pre-anoxic and post-anoxic periods. TOC, NH4+-N, and TN removal efficiencies were 98.76 ± 0.95 %, 98.52 ± 0.48 %, and 88.23 ± 0.62 %, respectively, at optimum conditions. Breakpoints in the pH, DO, and ORP curves provided a clear understanding of biochemical reactions happening in the reactor. Inhibition studies showed that 27.69 % of NH4+-N was removed through nitrogen removal pathways such as heterotrophic nitrification or direct conversion, and 20.55 % of TN was removed through aerobic denitrification. Microbial community analysis confirmed the presence of heterotrophic nitrifiers and aerobic denitrifiers. This study highlighted that the varied redox conditions offered by limited aeration would be beneficial for nitrogen removal, thereby reducing the energy usage and operating costs.
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Desnitrificação , Nitrogênio , Reatores Biológicos , Carbono/metabolismo , Nitrificação , Nitrogênio/metabolismo , Esgotos , Águas ResiduáriasRESUMO
Transcatheter heart valve replacement is becoming a more routine procedure, and this is further supported by positive outcomes from studies involving low-risk patients. Nevertheless, the lack of long-term transcatheter heart valve (TAV) durability is still one of the primary concerns. As a result, more research has been focused on improving durability through various methods such as valve design, computational modeling, and material selection. Recent advancements in polymeric valve fabrication showed that linear low-density polyethylene (LLDPE) could be used as leaflet material for transcatheter heart valves. In this paper, a parametric study of computational simulations showed stress distribution on the leaflets of LLDPE-TAV under diastolic load, and the results were used to improve the stent design. The in silico experiment also tested the effect of shock absorbers in terms of valve durability. The results demonstrated that altering specific stent angles can significantly lower peak stress on the leaflets (13.8 vs. 6.07 MPa). Implementing two layers of shock absorbers further reduces the stress value to 4.28 MPa. The pinwheeling index was assessed, which seems to correlate with peak stress. Overall, the parametric study and the computational method can be used to analyze and improve valve durability.
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Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Valva Aórtica , Simulação por Computador , Humanos , Modelos Cardiovasculares , Polietileno , Desenho de Prótese , Estresse Mecânico , Substituição da Valva Aórtica Transcateter/métodosRESUMO
SARS-CoV-2 is a pandemic coronavirus that causes severe respiratory disease (COVID-19) in humans and is responsible for millions of deaths around the world since early 2020. The virus affects the human respiratory cells through its spike (S) proteins located at the outer shell. To monitor the rapid spreading of SARS-CoV-2 and to reduce the deaths from the COVID-19, early detection of SARS-CoV-2 is of utmost necessity. This report describes a flexible colorimetric biosensor capable of detecting the S protein of SARS-CoV-2. The colorimetric biosensor is made of polyurethane (PU)-polydiacetylene (PDA) nanofiber composite that was chemically functionalized to create a binding site for the receptor molecule-nucleocapsid antibody (anti-N) protein of SARS-CoV-2. After the anti-N protein conjugation to the functionalized PDA fibers, the PU-PDA-NHS-anti fiber was able to detect the S protein of SARS-CoV-2 at room temperature via a colorimetric transition from blue to red. The PU-PDA nanofiber-based biosensors are flexible and lightweight and do not require a power supply such as a battery when the colorimetric detection to S protein occurs, suggesting a sensing platform of wearable devices and personal protective equipment such as face masks and medical gowns for real-time monitoring of virus contraction and contamination. The wearable biosensors could significantly power mass surveillance technologies to fight against the COVID-19 pandemic. Supplementary Information: The online version contains supplementary material available at 10.1007/s44164-022-00022-z.
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Hydroxyapatite is commonly used in tissue engineered scaffolds for bone regeneration due to its excellent bioactivity and slow degradation rate in the human body. A method of layer-wise, photopolymerized viscous extrusion, a type of additive manufacturing, was developed to fabricate hydroxyapatite gyroid scaffolds with 60%, 70%, and 80% porosities. This study uses this method to produce and evaluate calcium phosphate-based scaffolds. Gyroid topology was selected due to its interconnected porosity and superior, isotropic mechanical properties compared to typical rectilinear lattice structures. These 3D printed scaffolds were mechanically tested in compression and examined to determine the relationship between porosity, ultimate compressive strength, and fracture behavior. Compressive strength increased with decreasing porosity. Ultimate compressive strengths of the 60% and 70% porous gyroids are comparable to that of human cancellous bone, and higher than previously reported for hydroxyapatite rectilinear scaffolds. These gyroid scaffolds exhibited ultimate compressive strength increases between 1.5 and 6.5 times greater than expected, based on volume of material, as porosity is decreased. The Weibull moduli, a measure of failure predictability, were predictive of failure mode and found to be in the accepted range for engineering ceramics. The gyroid scaffolds were also found to be self-reinforcing such that initial failures due to minor manufacturing inconsistencies did not appear to be the primary cause of early failure of the scaffold. The porous gyroids exhibited scaffold failure characteristics that varied with porosity, ranging from monolithic failure to layer-by-layer failure, and demonstrated self-reinforcement in each porosity tested.
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Durapatita , Alicerces Teciduais , Osso e Ossos , Força Compressiva , Durapatita/química , Humanos , Porosidade , Engenharia Tecidual , Alicerces Teciduais/químicaRESUMO
The pharmacy support workforce (PSW) is the mid-level cadre of the global pharmacy profession, referring to pharmacy technicians, assistants and other cadres that assist in the delivery of pharmaceutical services in a variety of practice contexts. The PSW undertake technical tasks delegated under the supervision of a pharmacist or performed collaboratively. The PSW are not intended to replace pharmacists, but rather work side-by-side with the pharmacist to achieve a shared goal. However, extensive variation in the PSW exists globally, ranging from an educated, regulated, and highly effective workforce in some countries to unrecognized or non-existent in others. Vast differences in education requirements, specific roles, regulatory oversight, and need for pharmacist supervision, inhibit the development and advancement of a global PSW. As clinical care providers, pharmacists worldwide need for a competent support workforce. Without the confidence to delegate technical responsibilities to a well-trained and capable PSW, pharmacists will be unable to fully deliver advanced clinical roles. A clear vision for the role of the PSW in the expanding scope of pharmacy practice is needed. One organization working to unite global efforts in this area is the International Pharmaceutical Federation (FIP). The FIP Workforce Development Hub Pharmacy Technicians & Support Workforce Strategic Platform was established to address the pharmacy workforce shortage in low and middle-income countries. Further developments were made in 2019, with the creation of a representative global PSW advisory panel, to provide guidance towards the development of the global PSW. Provision of frameworks and strategic input to support quality in education, development of legislative frameworks, guidelines for registration and licensure, and advice on appropriate role advancement are critical to move the PSW forward. In order to produce substantial advancement of roles and recognition of the PSW and advancement of pharmacists as patient care providers, global collaborative work is needed.
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Assistência Farmacêutica , Farmácias , Farmácia , Humanos , Farmacêuticos , Técnicos em Farmácia/educação , Papel Profissional , Recursos HumanosRESUMO
OBJECTIVES: To identify neuropsychological and structural brain changes using a combination of high-resolution structural and diffusion tensor imaging in pediatric bipolar disorder (PBD) with psychosis (presence of delusions and or hallucinations). METHODS: We recruited 15 patients and 20 euthymic age- and gender-matched healthy controls. All subjects underwent high-resolution structural and diffusion tensor imaging. Voxel-based morphometry (VBM), tract-based spatial statistics (TBSS), and probabilistic tractography were used to analyse magnetic resonance imaging data. RESULTS: The PBD subjects had normal overall intelligence with specific impairments in working memory, executive function, language function, and verbal memory. Reduced gray matter (GM) density was found in the left orbitofrontal cortex, left pars triangularis, right premotor cortex, occipital cortex, right occipital fusiform gyrus, and right crus of the cerebellum. TBSS analysis showed reduced fractional anisotropy (FA) in the anterior corpus callosum. Probabilistic tractography from this cluster showed that this region of the corpus callosum is connected with the prefrontal cortices, including those regions whose density is decreased in PBD. In addition, FA change was correlated with verbal memory and working memory, while more widespread reductions in GM density correlated with working memory, executive function, language function, and verbal memory. CONCLUSIONS: The findings suggest widespread cortical changes as well as specific involvement of interhemispheric prefrontal tracts in PBD, which may reflect delayed myelination in these tracts.