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1.
PLOS Glob Public Health ; 4(3): e0002813, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38507416

RESUMO

HIV services for key populations (KP) at higher risk of HIV infection are often delivered by community-based organizations. To achieve HIV epidemic control, countries need to scale up HIV services for KP. Little is known about the management practices of community-based organizations delivering health services. We explored the management practices and facility characteristics of community-based health facilities providing HIV services to key populations as part of the LINKAGES program in Kenya and Malawi. We collected information on management practices from 45 facilities called drop-in centers (DICs) during US Government FY 2019, adapting the World Management Survey to the HIV community-based health service delivery context. We constructed management domain scores for each facility. We then analyzed the statistical correlations between management domains (performance monitoring, people management, financial management, and community engagement) and facility characteristics (e.g., number of staff, organization maturity, service scale) using ordinary least square models. The lowest mean management domain scores were found for people management in Kenya (38.3) and financial management in Malawi (25.7). The highest mean scores in both countries were for performance monitoring (80.9 in Kenya and 82.2 in Malawi). Within each management domain, there was significant variation across DICs, with the widest ranges in scores (0 to 100) observed for financial management and community involvement. The DIC characteristics we considered explained only a small proportion of the variation in management domain scores across DICs. Community-based health facilities providing HIV services to KP can achieve high levels of management in a context where they receive adequate levels of above-facility support and oversight-even if they deliver complex services, rely heavily on temporary workers and community volunteers, and face significant financial constraints. The variation in scores suggests that some facilities may require more above-facility support and oversight than others.

2.
Psychol Rev ; 131(1): 311-320, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36649163

RESUMO

When a circular coin is rotated in depth, is there any sense in which it comes to resemble an ellipse? While this question is at the center of a rich and divided philosophical tradition (with some scholars answering affirmatively and some negatively), Morales et al. (2020, 2021) took an empirical approach, reporting 10 experiments whose results favor such perspectival similarity. Recently, Burge and Burge (2022) offered a vigorous critique of this work, objecting to its approach and conclusions on both philosophical and empirical grounds. Here, we answer these objections on both fronts. We show that Burge and Burge's critique rests on misunderstandings of Morales et al.'s claims; of the relation between the data and conclusions; and of the philosophical context in which the work appears. Specifically, Burge and Burge attribute to us a much stronger (and stranger) view than we hold, involving the introduction of "a new entity" located "in some intermediate position(s) between the distal shape and the retinal image." We do not hold this view. Indeed, once properly understood, most of Burge and Burge's objections favor Morales et al.'s claims rather than oppose them. Finally, we discuss several questions that remain unanswered, and reflect on a productive path forward on these issues of foundational scientific and philosophical interest. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

3.
J Comput Chem ; 45(10): 671-682, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38095321

RESUMO

With the simplest-level electron nuclear dynamics (SLEND) method, we test standard Slater-type-orbital/contracted-Gaussian-functions (STO/CGFs) basis sets for the simulation of direct ionizations (DIs), charge transfers (CTs), and target excitations (TEs) in H+ + H at ELab = 0.1-100 keV. SLEND is a time-dependent, variational, on-the-fly, and nonadiabatic method that treats nuclei and electrons with classical dynamics and a Thouless single-determinantal state, respectively. While previous tests for CTs and TEs exist, this is the first SLEND/STO/CGFs test for challenging DIs. Spin-orbitals with negative/positive energies are treated as bound/unbound states for bound-to-bound (CT and TE) and bound-to-unbound (DI) transitions. SLEND/STO/CGFs simulations correctly reproduce all the features of DIs, CTs and TEs over all the considered impact parameters and energies. SLEND/STO/CGFs simulations correctly predict CT integrals cross-sections (ICSs) over all the considered energies and predict satisfactory DI and TE ICSs within some energy ranges. Strategies to improve SLEND/STO/CGFs for DI predictions are discussed.

4.
Polymers (Basel) ; 15(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37896318

RESUMO

Up to now, rubber materials have been used in a wide range of applications, from automotive parts to special-design engineering pieces, as well as in the pharmaceutical, food, electronics, and military industries, among others. Since the discovery of the vulcanization of natural rubber (NR) in 1838, the continuous demand for this material has intensified the quest for a synthetic substitute with similar properties. In this regard, synthetic polyisoprene rubber (IR) emerged as an attractive alternative. However, despite the efforts made, some properties of natural rubber have been difficult to match (i.e., superior mechanical properties) due not only to its high content of cis-1,4-polyisoprene but also because its structure is considered a naturally occurring nanocomposite. In this sense, cutting-edge research has proposed the synthesis of nanocomposites with synthetic rubber, obtaining the same properties as natural rubber. This review focuses on the synthesis, structure, and properties of natural and synthetic rubber, with a special interest in the synthesis of IR nanocomposites, giving the reader a comprehensive reference on how to achieve a mimic of NR.

5.
J Therm Biol ; 117: 103697, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37683357

RESUMO

The interaction between climatic conditions and the ability of organisms to maintain homeostasis regulates the distribution of species on the planet. However, its influence on macroevolutionary dynamics is not well understood. It has been suggested that diversification rates will be different in lineages with narrow thermal niches (specialists) to diversification rates in generalist lineages, but the evidence for this is elusive. Here, we tested this hypothesis by using the most diverse (in species richness and geographic range variation) tropical bat genus within the Phyllostomidae family. We estimated the realized thermal niche breadth of Sturnira species from their geographic range and categorized them as generalists, cold specialists, or warm specialists. We compared dynamic evolutionary models that differ in 1) niche breadth evolution, 2) parental niche breadth inheritance, and 3) whether niche breadth evolution is associated with shifts in diversification rates. Our best-performing model indicates that most Sturnira species arose as specialists in warm climates and that over time, their niche breadth broadens, and just a subset of those species becomes specialists in cold environments. We found that the evolution of realized thermal niche breadth causes fluctuations in per-lineage rates of diversification, where warm specialists boast the highest speciation rates. However, we found no evidence of these changes in niche neither triggering nor being a result of speciation events themselves; this suggests that diversification events in Sturnira could instead depend on allopatric speciation processes such as the development of geographic barriers.

6.
Dalton Trans ; 52(32): 11361-11362, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37545463

RESUMO

Correction for 'Iridium-(κ2-NSi) catalyzed dehydrogenation of formic acid: effect of auxiliary ligands on the catalytic performance' by Alejandra Gomez-España et al., Dalton Trans., 2023, 52, 6722-6729, https://doi.org/10.1039/d3dt00744h.

7.
Vet Parasitol ; 320: 109971, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37331171

RESUMO

Acacia bilimekii is a plant with a high content of protein, fibre, and condensed tannins, making it an excellent feed for small ruminants with anthelmintic potential. This study aimed to evaluate the ovicidal activity of a hydroalcoholic extract (Ab-HA) and fractions from A. bilimekii aerial parts on Haemonchus contortus. The ovicidal activity of the Ab-HA extract and its fractions obtained by chromatographic fractionation were evaluated through the egg hatching inhibition (EHI) test. The results showed that the Ab-HA extract had 91% EHI at 20,000 µg/mL with a mean effective concentration (EC50) of 9260 µg/mL. After liquid-liquid fractionation of Ab-HA extract, the aqueous fraction (Ab-Aq) did not show ovicidal activity, whereas the organic fraction (Ab-EtOAc) showed a better EHI than the Ab-HA extract (98.9% at 2500 µg/mL). Then, the chemical fractionation of Ab-EtOAc allowed obtaining six bioactive fractions (AbR12-17) with an EHI greater than 90% at 1500 µg/mL. The best treatment was AbR15 (98.7% EHI at 750 µg/mL). Chemical analysis by HPLC-PDA of AbR15 indicated the presence of p-coumaric acid and the flavone luteolin as major compounds. Additionally, the commercial p-coumaric acid standard was evaluated in the EHI assay and showed an EHI of 97% at 62.5 µg/mL. Meanwhile, the confocal laser scanning microscopy analysis demonstrated a colocalization effect between p-coumaric acid and the H. contortus embryonated eggs. These results indicate that due to their major chemical compounds (including p-coumaric acid), the aerial parts of the plant A. bilimekii, could be considered as natural potential tool for controlling haemonchosis in small ruminants.


Assuntos
Acacia , Anti-Helmínticos , Haemonchus , Animais , Acacia/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Óvulo , Anti-Helmínticos/farmacologia , Anti-Helmínticos/química , Larva , Componentes Aéreos da Planta
9.
Glob Health Sci Pract ; 11(3)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37348941

RESUMO

INTRODUCTION: Timely data on HIV service costs are critical for estimating resource needs and allocating funding, but few data exist on the cost of HIV services for key populations (KPs) at higher risk of HIV infection in low- and middle-income countries. We aimed to estimate the total and per contact annual cost of providing comprehensive HIV services to KPs to inform planning and budgeting decisions. METHODS: We collected cost data from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV (LINKAGES) program in Kenya and Malawi serving female and male sex workers, men who have sex with men, and transgender women. Data were collected prospectively for fiscal year (FY) 2019 and retrospectively for start-up activities conducted in FY2015 and FY2016. Data to estimate economic costs from the provider's perspective were collected from LINKAGES headquarters, country offices, implementing partners (IPs), and drop-in centers (DICs). We used top-down and bottom-up cost estimation approaches. RESULTS: Total economic costs for FY2019 were US$6,175,960 in Kenya and US$4,261,207 in Malawi. The proportion of costs incurred in IPs and DICs was 66% in Kenya and 42% in Malawi. The costliest program areas were clinical services, management, peer outreach, and monitoring and data use. Mean cost per contact was US$127 in Kenya and US$279 in Malawi, with a mean cost per contact in DICs and IPs of US$63 in Kenya and US$104 in Malawi. CONCLUSION: Actions undertaken above the service level in headquarters and country offices along with those conducted below the service level in communities, comprised important proportions of KP HIV service costs. The costs of pre-service population mapping and size estimation activities were not negligible. Costing studies that focus on the service level alone are likely to underestimate the costs of delivering HIV services to KPs.


Assuntos
Infecções por HIV , Profissionais do Sexo , Minorias Sexuais e de Gênero , Humanos , Masculino , Feminino , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Quênia/epidemiologia , Malaui/epidemiologia , Estudos Retrospectivos
10.
Dalton Trans ; 52(20): 6722-6729, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37129044

RESUMO

The iridium(III) complexes [Ir(H)(Cl)(κ2-NSitBu2)(κ2-bipyMe2)] (2) and [Ir(H)(OTf)(κ2-NSitBu2)(κ2-bipyMe2)] (3) (NSitBu2 = {4-methylpyridine-2-yloxy}ditertbutylsilyl) have been synthesized and characterized including X-ray studies of 3. A comparative study of the catalytic activity of complexes 2, 3, [Ir(H)(OTf)(κ2-NSitBu2)(coe)] (4), and [Ir(H)(OTf)(κ2-NSitBu2)(PCy3)] (5) (0.1 mol%) as catalysts precursors for the solventless formic acid dehydrogenation (FADH) in the presence of Et3N (40 mol%) at 353 K has been performed. The highest activity (TOF5 min ≈ 3260 h-1) has been obtained with 3 at 373 K. However, at that temperature the FTIR spectra show traces of CO together with the desired products (H2 and CO2). Thus, the best performance was achieved at 353 K (TOF5 min ≈ 1210 h-1 and no observable CO). Kinetic studies at variable temperature show that the activation energy of the 3-catalyzed FADH process is 16.76 kcal mol-1. Kinetic isotopic effect (5 min) values of 1.6, 4.5, and 4.2 were obtained for the 3-catalyzed dehydrogenation of HCOOD, DCOOH, and DCOOD, respectively, at 353 K. The strong KIE found for DCOOH and DCOOD evidenced that the hydride transfer from the C-H bond of formic acid to the metal is the rate-determining step of the process.

11.
Neurol Genet ; 9(3): e200072, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37168776

RESUMO

Objective: This study reports 2 unrelated individuals with Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome who presented with a metabolic stroke, which has not been commonly reported as a clinical manifestation of this syndrome. Methods: Two female children were identified after presenting to our institution with a metabolic stroke and carried a diagnosis of ZTTK syndrome because of their clinical characteristics and previous genetic testing demonstrating pathogenic variants in SON. Results: Both individuals presented with acute-onset left hemiplegia. They underwent workup, and corresponding metabolic stroke was identified on brain MRI. Both individuals recovered with good functional outcome. One individual was treated with l-arginine, ubiquinol, and levocarnitine. The other individual recovered without any intervention. Discussion: ZTTK syndrome is a rare condition caused by pathogenic variants in SON. This syndrome is characterized by global developmental delay, short stature, facial dysmorphisms, seizures, hypotonia, and brain abnormalities. A metabolic stroke has not been reported as a common manifestation. SON has been reported to play a role in mitochondrial function. This can explain why metabolic stroke can be seen in individuals with ZTTK syndrome. It is important to recognize that metabolic stroke can be a clinical manifestation of ZTTK syndrome because it carries clinical and therapeutic implications.

12.
J Econ Entomol ; 116(3): 1033-1037, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37156231

RESUMO

Reticulitermes flavipes is the most invasive species in its genus and is responsible for causing significant damage to human structures in areas where it has been introduced. Although it has already become established in Chile and Uruguay, it had not previously been reported in Argentina. In this study, we report the first detection of this species in Buenos Aires, the capital of Argentina. The colony was already producing alates, and species identification was confirmed through both morphology and mitochondrial gene 16S rRNA analysis. Our results, while not conclusive, suggest that this introduction was independent from the one that occurred in Chile and Uruguay, and potentially originated from the United States. The detection of R. flavipes in Argentina is significant because it highlights the potential for this species to establish itself in new regions and underscores the need for future research on and control of R. flavipes in this country.


Assuntos
Isópteros , Humanos , Animais , Argentina , RNA Ribossômico 16S/genética , Uruguai
13.
Dalton Trans ; 52(21): 7353, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37212745

RESUMO

Correction for 'Iridium-(κ2-NSi) catalyzed dehydrogenation of formic acid: effect of auxiliary ligands on the catalytic performance' by Alejandra Gomez-España et al., Dalton Trans., 2023, https://doi.org/10.1039/d3dt00744h.

14.
Curr Biol ; 33(13): 2690-2701.e5, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37201521

RESUMO

The stability of endosymbiotic associations between eukaryotes and bacteria depends on a reliable mechanism ensuring vertical inheritance of the latter. Here, we demonstrate that a host-encoded protein, located at the interface between the endoplasmic reticulum of the trypanosomatid Novymonas esmeraldas and its endosymbiotic bacterium Ca. Pandoraea novymonadis, regulates such a process. This protein, named TMP18e, is a product of duplication and neo-functionalization of the ubiquitous transmembrane protein 18 (TMEM18). Its expression level is increased at the proliferative stage of the host life cycle correlating with the confinement of bacteria to the nuclear vicinity. This is important for the proper segregation of bacteria into the daughter host cells as evidenced from the TMP18e ablation, which disrupts the nucleus-endosymbiont association and leads to greater variability of bacterial cell numbers, including an elevated proportion of aposymbiotic cells. Thus, we conclude that TMP18e is necessary for the reliable vertical inheritance of endosymbionts.


Assuntos
Trypanosomatina , Trypanosomatina/microbiologia , Bactérias , Simbiose/fisiologia , Eucariotos
15.
Environ Monit Assess ; 195(6): 731, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231316

RESUMO

Amazon aquatic systems have been affected by organic pollution from urbanized regions. This study was conducted to determine the levels, sources, and distribution patterns of 16 polycyclic aromatic hydrocarbons (PAHs) and 6 steroid markers in surficial sediments from an important urbanized Amazon estuarine system (Belém, PA, Northern Brazil). Total PAH concentration (∑PAH) ranged from 878.2 to 9905.7 ng g-1, 3295.2 ng g-1 on average, suggesting a highly contaminated environment. PAH molecular ratios and statistical analysis indicated that PAH originated from a mixture of local sources emissions, mainly related to the combustion of fossil fuels and biomass. Coprostanol levels (maximum concentration = 292.52 ng g-1) could be compared to the mid-range reported in the literature. Studied stations, except for one, presented sterol ratio data indicating organic matter related to untreated sewage. Sterols indicative of sewage contamination showed a correlation with pyrogenic PAH amounts which are transported by the same channels where sewage is discharged.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Brasil , Estuários , Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise , Esgotos/análise , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise
16.
BMC Health Serv Res ; 23(1): 337, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37016402

RESUMO

BACKGROUND: Data remain scarce on the costs of HIV services for key populations (KPs). The objective of this study was to bridge this gap in the literature by estimating the unit costs of HIV services delivered to KPs in the LINKAGES program in Kenya and Malawi. We estimated the mean total unit costs of seven clinical services: post-exposure prophylaxis (PEP), pre-exposure prophylaxis (PrEP), HIV testing services (HTS), antiretroviral therapy (ART), sexually transmitted infection (STI) services, sexual and reproductive health (SRH) services, and management of sexual violence (MSV). These costs take into account the costs of non-clinical services delivered alongside clinical services and the pre-service and above-service program management integral to the LINKAGES program. METHODS: Data were collected at all implementation levels of the LINKAGES program including 30 drop-in-centers (DICs) in Kenya and 15 in Malawi. This study was conducted from the provider's perspective. We estimated economic costs for FY 2019 and cost estimates include start-up costs. Start-up and capital costs were annualized using a discount rate of 3%. We used a combination of top-down and bottom-up costing approaches. Top-down methods were used to estimate the costs of headquarters, country offices, and implementing partners. Bottom-up micro-costing methods were used to measure the quantities and prices of inputs used to produce services in DICs. Volume-weighted mean unit costs were calculated for each clinical service. Costs are presented in 2019 United States dollars (US$). RESULTS: The mean total unit costs per service ranged from US$18 (95% CI: 16, 21) for STI services to US$635 (95% CI: 484, 785) for PrEP in Kenya and from US$41 (95% CI: 37, 44) for STI services to US$1,240 (95% CI 1156, 1324) for MSV in Malawi. Clinical costs accounted for between 21 and 59% of total mean unit costs in Kenya, and between 25 and 38% in Malawi. Indirect costs-including start-up activities, the costs of KP interventions implemented alongside clinical services, and program management and data monitoring-made up the remaining costs incurred. CONCLUSIONS: A better understanding of the cost of HIV services is highly relevant for budgeting and planning purposes and for optimizing HIV services. When considering all service delivery costs of a comprehensive HIV service package for KPs, costs of services can be significantly higher than when considering direct clinical service costs alone. These estimates can inform investment cases, strategic plans and other budgeting exercises.


Assuntos
Infecções por HIV , Infecções Sexualmente Transmissíveis , Humanos , Quênia/epidemiologia , Malaui/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Atenção à Saúde
17.
Phys Chem Chem Phys ; 25(13): 9336-9348, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36920434

RESUMO

Bones are connective tissues mainly made of collagen proteins with calcium phosphate deposits. They undergo constant remodeling, including destroying existing bones tissues (known as bone resorption) and rebuilding new ones. Bone remodeling has been well-described in mammals, but it is not the case in fish. Here, we focused on the mobile phase of the bone vascular system by carefully preserving moisture in adult Atlantic herring intermuscular bones. We detected pore water with high ionic strength and soluble degraded peptides whose 1H-transverse relaxation times, T2s, exceed 15 milliseconds. With favorable T2s, we incorporated a solution state spinlock scheme into the INEPT techniques to unequivocally demonstrate collagen degradation. In addition, we detected a substantial amount of inorganic phosphate in solution with 31P-NMR in the considerable background of solid hydroxyapatite calcium phosphate by saturation recovery experiment. It is consistent with the idea that bone resorption degrades bone collagen and releases calcium ions and phosphate ions in the pore water with increased ionic strength. Our report is the first to probe the resorption process in the heterogenous bone microstructure with a rigorous characterization of 1H and 13C relaxation behavior and direct assignments. In addition, we contribute to the fish bones literature by investigating fish bone remodeling using NMR for the first time.


Assuntos
Reabsorção Óssea , Osso e Ossos , Animais , Fosfatos de Cálcio , Peixes , Durapatita , Colágeno , Mamíferos
18.
Curr Biol ; 33(1): 28-40.e7, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36480982

RESUMO

The trypanosomatid Angomonas deanei is a model to study endosymbiosis. Each cell contains a single ß-proteobacterial endosymbiont that divides at a defined point in the host cell cycle and contributes essential metabolites to the host metabolism. Additionally, one endosymbiont gene, encoding an ornithine cyclodeaminase (OCD), was transferred by endosymbiotic gene transfer (EGT) to the nucleus. However, the molecular mechanisms mediating the intricate host/symbiont interactions are largely unexplored. Here, we used protein mass spectrometry to identify nucleus-encoded proteins that co-purify with the endosymbiont. Expression of fluorescent fusion constructs of these proteins in A. deanei confirmed seven host proteins to be recruited to specific sites within the endosymbiont. These endosymbiont-targeted proteins (ETPs) include two proteins annotated as dynamin-like protein and peptidoglycan hydrolase that form a ring-shaped structure around the endosymbiont division site that remarkably resembles organellar division machineries. The EGT-derived OCD was not among the ETPs, but instead localizes to the glycosome, likely enabling proline production in the glycosome. We hypothesize that recalibration of the metabolic capacity of the glycosomes that are closely associated with the endosymbiont helps to supply the endosymbiont with metabolites it is auxotrophic for and thus supports the integration of host and endosymbiont metabolic networks. Hence, scrutiny of endosymbiosis-induced protein re-localization patterns in A. deanei yielded profound insights into how an endosymbiotic relationship can stabilize and deepen over time far beyond the level of metabolite exchange.


Assuntos
Bactérias , Trypanosomatina , Bactérias/genética , Trypanosomatina/genética , Trypanosomatina/metabolismo , Trypanosomatina/microbiologia , Simbiose/genética
19.
Phys Chem Chem Phys ; 25(3): 2019-2034, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36545768

RESUMO

Following our preceding research [P. M. McLaurin, R. Merritt, J. C. Domínguez, E. S. Teixeira and J. A. Morales, Phys. Chem. Chem. Phys., 2019, 21, 5006], we present an electron nuclear dynamics (END) investigation of H+ + H2O at ELab = 28.5-200.0 eV in conjunction with a computational procedure to induce symmetry breaking during evolution. The investigated system is a computationally feasible prototype to simulate water radiolysis reactions in ion cancer therapy. END is a time-dependent, variational, non-adiabatic, and on-the-fly method, which utilizes classical mechanics for nuclei and a Thouless single-determinantal state for electrons. In this study, a procedure inherent to END introduces low degrees of symmetry breaking into the reactants' restricted Hartree-Fock (RHF) state to induce a higher symmetry breaking during evolution. Specifically, the Thouless exponential operator acting on the RHF reference generates an axial spin density wave (ASDW) state according to Fukutome's analysis of HF symmetry breaking; this state exhibits spatial and spin symmetry breaking. By varying a Thouless parameter, low degrees of symmetry breaking are introduced into ASDW states. After starting the dynamics from those states, higher degrees of symmetry breaking may subsequently emerge as dictated by the END equations without ad hoc interventions. Simulations starting from symmetry-conforming states preserve the symmetry features during dynamics, whereas simulations starting from symmetry-broken states display an upsurge of symmetry breaking once the reactants collide. Present simulations predict three types of reactions: (I) projectile scattering, (II) hydrogen substitution, and (III) water radiolysis into H + OH and 2H + O fragments. Remarkably, symmetry breaking considerably increases the extent of the target-to-projectile electron transfers (ETs) occurring during the above reactions. Then, with symmetry breaking, 1-ET differential and integral cross sections increase in value, whereas 0-ET differential cross sections and primary rainbow scattering angles decrease. More importantly, END properties calculated from symmetry-breaking simulations exhibit better agreement with the experimental data. Notably, END 1-ET integral cross sections with symmetry breaking compare better with their experimental counterparts than 1-ET integral cross sections from high-level close-coupling calculations; moreover, END validates an undetected rainbow scattering peak inferred from the experimental data. A discussion of our symmetry-breaking procedure in the context of Fukutome's analysis of HF symmetry breaking is also presented.


Assuntos
Elétrons , Neoplasias , Humanos , Hidrogênio , Água , Transporte de Elétrons
20.
Eur Spine J ; 32(1): 140-148, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36443510

RESUMO

PURPOSE: In this meta-analysis, we analyzed the efficacy and safety of anterior vertebral body tethering in patients with adolescent idiopathic scoliosis. METHODS: We performed a literature search and analyzed the following data: baseline characteristics, efficacy measures (corrections of the main thoracic curve, proximal thoracic curve, and thoracolumbar curve, thoracic kyphosis, lumbosacral lordosis, rib hump, lumbar prominence and SRS-22 scores, and complications. Analyses were performed with Cochrane's Review Manager version 5.4. RESULTS: Twelve studies met the inclusion criteria. Significant corrections of the main thoracic (MD 22.51, 95% CI 12.93 to 32.09) proximal thoracic (MD 10.14°, 95% CI 7.25° to 13.02°), and thoracolumbar curve (MD 12.16, 95% CI 9.14 to 15.18) were found. No statistically significant corrections were observed on the sagittal plane assessed by thoracic kyphosis (MD - 0.60°, 95% CI - 2.45 to 1.26; participants = 622; studies = 4; I2 = 36%) and lumbosacral lordosis (MD 0.19°, 95% CI - 2.16° to 2.54°). Significant corrections were identified for rib hump (MD 5.26°, 95% CI 4.19° to 6.32°) and lumbar prominence (MD 1.20°, 95% CI 0.27° to 2.13°) at final follow-up. Significant improvements of total SRS-22 score (MD - 0.96, 95% CI - 1.10 to - 0.83) were achieved at final follow-up. The most common complication was overcorrection (8.0%) and tether breakage (5.9%), with a reoperation rate of 10.1%. CONCLUSIONS: Anterior vertebral body tethering is effective to reduce the curve in the coronal plane and clinical deformity. Maximum correction is achieved at one year. The method should, however, be optimized to reduce the rate of complications.


Assuntos
Cifose , Lordose , Escoliose , Fusão Vertebral , Humanos , Adolescente , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Lordose/diagnóstico por imagem , Lordose/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Corpo Vertebral , Radiografia , Fusão Vertebral/métodos , Cifose/cirurgia , Resultado do Tratamento , Estudos Retrospectivos
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