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A catalogue of neuronal cell types has often been called a 'parts list' of the brain1, and regarded as a prerequisite for understanding brain function2,3. In the optic lobe of Drosophila, rules of connectivity between cell types have already proven to be essential for understanding fly vision4,5. Here we analyse the fly connectome to complete the list of cell types intrinsic to the optic lobe, as well as the rules governing their connectivity. Most new cell types contain 10 to 100 cells, and integrate information over medium distances in the visual field. Some existing type families (Tm, Li, and LPi)6-10 at least double in number of types. A new serpentine medulla (Sm) interneuron family contains more types than any other. Three families of cross-neuropil types are revealed. The consistency of types is demonstrated by analysing the distances in high-dimensional feature space, and is further validated by algorithms that select small subsets of discriminative features. We use connectivity to hypothesize about the functional roles of cell types in motion, object and colour vision. Connectivity with 'boundary types' that straddle the optic lobe and central brain is also quantified. We showcase the advantages of connectomic cell typing: complete and unbiased sampling, a rich array of features based on connectivity and reduction of the connectome to a substantially simpler wiring diagram of cell types, with immediate relevance for brain function and development.

Many animals use visual information to navigate1-4, but how such information is encoded and integrated by the navigation system remains incompletely understood. In Drosophila melanogaster, EPG neurons in the central complex compute the heading direction5 by integrating visual input from ER neurons6-12, which are part of the anterior visual pathway (AVP)10,13-16. Here we densely reconstruct all neurons in the AVP using electron-microscopy data17. The AVP comprises four neuropils, sequentially linked by three major classes of neurons: MeTu neurons10,14,15, which connect the medulla in the optic lobe to the small unit of the anterior optic tubercle (AOTUsu) in the central brain; TuBu neurons9,16, which connect the AOTUsu to the bulb neuropil; and ER neurons6-12, which connect the bulb to the EPG neurons. On the basis of morphologies, connectivity between neural classes and the locations of synapses, we identify distinct information channels that originate from four types of MeTu neurons, and we further divide these into ten subtypes according to the presynaptic connections in the medulla and the postsynaptic connections in the AOTUsu. Using the connectivity of the entire AVP and the dendritic fields of the MeTu neurons in the optic lobes, we infer potential visual features and the visual area from which any ER neuron receives input. We confirm some of these predictions physiologically. These results provide a strong foundation for understanding how distinct sensory features can be extracted and transformed across multiple processing stages to construct higher-order cognitive representations.

Games are often used to foster student engagement and motivation to learn content, such as mathematics. Although digital games dominate game-based learning research, the table games commonly used in classrooms warrant investigation. Especially for mathematics learning, prior research has not taken into account content-specific frameworks. Integer arithmetic (i.e., calculations with negative numbers) is a difficult topic that is crucial for later mathematics. Thus, this study synthesized multiple theoretical perspectives to understand students' experiences playing games during an integer unit. A mixed methods design study was conducted to answer the primary question: How was student experience (motivation to learn and engagement) related to game features? Student perspectives about the three integer games they played and observations of student engagement during gameplay were analyzed using perspectives from game design and the Cognitive Demand framework for mathematical tasks. Overall, students positively perceived playing games, however, individuals' motivation and engagement varied in relation to game features. Students provided valuable insights for research and practice as to which game features were engaging or motivating and why. Speed-based synchronous games that exclusively used skill, rather than a chance-skill balance induced stress and decreased motivation for many students. Thus, a critical implication was to first do no harm by selecting or designing classroom games that have features of turn-taking and chance. We suggest recommendations for mathematics learning and provide the STEM Classroom Games Features Framework to benefit research and practice of any STEM content area.

During beam time at a research facility, alignment and optimization of instrumentation, such as spectrometers, is a time-intensive task and often needs to be performed multiple times throughout the operation of an experiment. Despite the motorization of individual components, automated alignment solutions are not always available. In this study, a novel approach that combines optimisers with neural network surrogate models to significantly reduce the alignment overhead for a mobile soft X-ray spectrometer is proposed. Neural networks were trained exclusively using simulated ray-tracing data, and the disparity between experiment and simulation was obtained through parameter optimization. Real-time validation of this process was performed using experimental data collected at the beamline. The results demonstrate the ability to reduce alignment time from one hour to approximately five minutes. This method can also be generalized beyond spectrometers, for example, towards the alignment of optical elements at beamlines, making it applicable to a broad spectrum of research facilities.

Abstract Animals protect themself from microbial attacks by robust skins or a cuticle as in Caenorhabditis elegans. Nematode-trapping fungi, like Arthrobotrys flagrans, overcome the cuticle barrier and colonize the nematode body. While lytic enzymes are important for infection, small-secreted proteins (SSPs) without enzymatic activity, emerge as crucial virulence factors. Here, we characterized NipA (nematode induced protein) which A. flagrans secretes at the penetration site. In the absence of NipA, A. flagrans required more time to penetrate C. elegans. Heterologous expression of the fungal protein in the epidermis of C. elegans led to blister formation. NipA contains 13 cysteines, 12 of which are likely to form disulfide bridges, and the remaining cysteine was crucial for blister formation. We hypothesize that NipA interferes with cuticle integrity to facilitate fungal entry. Genome-wide expression analyses of C. elegans expressing NipA revealed mis-regulation of genes associated with extracellular matrix (ECM) maintenance and innate immunity.

RESUMO Objetivo elucidar os alcances formativos aos integrantes de atividade de extensão desenvolvida em unidade pediátrica hospitalar estruturada na contação de histórias e intervenções lúdicas. Método estudo qualitativo, apoiado nos referenciais do Interacionismo Simbólico e da Análise Temática Reflexiva. Foram realizadas entrevistas semiestruturadas únicas junto a nove graduandos, membros de atividade extensionista, desenvolvidas entre junho e julho de 2023, com duração média de 22 minutos. Resultados os participantes, estudantes dos cursos de graduação em enfermagem, medicina e pedagogia, apontaram contribuições formativas relacionadas à concepção de criança, hospitalização infantil e do lúdico enquanto tecnologia de cuidado integral. Os seguintes temas surgiram a partir da análise dos dados: “Ampliação da consideração pela criança hospitalizada e seu acompanhante”, “Formação profissional na perspectiva de um atendimento integral”; e “Valorização da incorporação do lúdico como recurso terapêutico”. Conclusões e implicações para a prática a atividade extensionista reverberou com reconhecimento e motivação para a adoção da contação de histórias e do lúdico na interação com a criança hospitalizada. Provocou ainda reflexões acerca do perfil profissional projetado na direção de compromisso e garantia ao cuidado humano e integral no âmbito da hospitalização infantil.

Many animals, including humans, navigate their surroundings by visual input, yet we understand little about how visual information is transformed and integrated by the navigation system. In Drosophila melanogaster , compass neurons in the donut-shaped ellipsoid body of the central complex generate a sense of direction by integrating visual input from ring neurons, a part of the anterior visual pathway (AVP). Here, we densely reconstruct all neurons in the AVP using FlyWire, an AI-assisted tool for analyzing electron-microscopy data. The AVP comprises four neuropils, sequentially linked by three major classes of neurons: MeTu neurons, which connect the medulla in the optic lobe to the small unit of anterior optic tubercle (AOTUsu) in the central brain; TuBu neurons, which connect the anterior optic tubercle to the bulb neuropil; and ring neurons, which connect the bulb to the ellipsoid body. Based on neuronal morphologies, connectivity between different neural classes, and the locations of synapses, we identified non-overlapping channels originating from four types of MeTu neurons, which we further divided into ten subtypes based on the presynaptic connections in medulla and postsynaptic connections in AOTUsu. To gain an objective measure of the natural variation within the pathway, we quantified the differences between anterior visual pathways from both hemispheres and between two electron-microscopy datasets. Furthermore, we infer potential visual features and the visual area from which any given ring neuron receives input by combining the connectivity of the entire AVP, the MeTu neurons’ dendritic fields, and presynaptic connectivity in the optic lobes. These results provide a strong foundation for understanding how distinct visual features are extracted and transformed across multiple processing stages to provide critical information for computing the fly’s sense of direction.

Objetivo: descrever as percepções de acompanhantes sobre o impacto da contação de histórias durante a hospitalização de crianças. Métodos: trata-se de estudo qualitativo, apoiado no Interacionismo Simbólico, desenvolvido na unidade de internação pediátrica de um Hospital Universitário. Foram entrevistadas, entre junho e julho de 2023, nove mulheres, acompanhantes de crianças hospitalizadas, que participaram da atividade semanal de contação de histórias. A análise dos dados foi direcionada pela Análise Temática de Conteúdo. Resultados: a contação de histórias foi significada enquanto um contraponto ao cotidiano entediante e imerso em preocupações que marcam a hospitalização infantil. Emergiram duas categorias temáticas da percepção das mães sobre contação de histórias no contexto da hospitalização de crianças, “Estreitamento das relações entre crianças, acompanhantes e contadores de histórias”, que contribuiu para o fortalecimento do vínculo entre acompanhante, criança e equipe multiprofissional e “Momento de acolhimento para as crianças e acompanhantes”, que revela o efeito de proporcionar um momento de distração, alegria e conforto para as mães. Conclusão: a contação de histórias promove ambiência propícia para o enfrentamento da doença, proporciona bem-estar, alegria e conforto para as mães acompanhantes. Impacta positivamente no comportamento das crianças e acompanhantes durante a internação e estimula sua continuidade no ambiente domiciliar.

Some goals of mathematics teacher education include ensuring that pre-service teachers (PSTs) have strong content knowledge, the skill to anticipate and interpret student thinking, the ability to plan how to respond, and the ability to critically select resources for instruction. These goals are especially challenging for the topic of geometric shapes. Thus, we share an instructional activity that focuses PSTs' attention on an inaccurate resource of geometric information, children's books, to accomplish these goals in mathematics content as well as methods courses. Analyses of surveys and content assessments conducted to assess efficacy of the Shape Book Critique Activity were interpreted with the Mathematical Knowledge for Teaching (MKT) framework. Based on the findings we suggest that this short 40-minute activity is a promising way to promote PSTs' growth in three aspects of MKT for geometric shapes.

Abstract Objective To analyze the childbirth experience focusing on the intervening factors and on the delivery method. Method A sequential and explanatory mixed-methods study guided by the World Health Organization document for positive childbirth experiences. The participants were puerperal women in a maternity teaching hospital from inland São Paulo (Brazil). The first quantitative stage involved descriptive analysis with Poisson regression of 265 answers to the “Termômetro da Iniciativa Hospital Amigo da Mulher e da Criança” (“Women- and Baby-Friendly Hospital Initiative Thermometer”) questionnaire. The second stage, qualitative, thematically analyzed the interviews conducted with 44 puerperal women who took part in the first stage. Data integration was by connection. The results and discussion The analysis by connection showed that among the factors that restricted the positive experience, C-section was predominant (61.9%), understood as an option due to fear of pain, the treatment modality and previous traumas. Restrictions referring to the presence of a companion (99.6%), not having privacy (83%), disrespectful situations (69.5%), too many touches (56.9%) and the absence of skin-to-skin contact (55%), among others, potentiated fear, loneliness, concern, shame, the perception of disrespect and insecurity with the assistance provided. The promoting factors were as follows: choosing the companion (95.4%) for collaborating in the safety perception, not having infections (83.9%), having continuous team monitoring (82.2%) and pain relief methods (78.9%), which were valued by the women. Conclusion The intervening factors that promoted positive experiences were related to clinical and protocol-related issues and to service availability. The restrictive factors were associated with excess interventions, deprivation of rights and of choice, absence of privacy and restriction referring to the presence of a companion. Women with a normal postpartum period felt more insecure and disrespected when compared to those subjected to C-sections, whose choices were considered, although they had lower prevalence of skin-to-skin contact. There is an urgent need to apprehend women's experiences and turn them into actions that guarantee their lives in a safe and respectful way.

Abstract Background The diagnosis of a life-limiting condition of a child in the perinatal or neonatal period is a threat to parental hopes. Hope is an interactional and multidimensional construct, and in palliative care, it is a determinant of quality of life, survival, acceptance and peaceful death. Objective To map scientific evidence on parents’ hope in perinatal and neonatal palliative care contexts. Method a scoping review theoretically grounded on Dufault and Martocchio’s Framework, following the Joanna Briggs Institute methodological recommendations. Searches were performed until May 2023 in the MEDLINE, CINAHL and PsycINFO databases. The searches returned 1341 studies. Results Eligible papers included 27 studies, most of which were carried out in the United States under a phenomenological or literature review approach. The centrality of women’s perspectives in the context of pregnancy and perinatal palliative care was identified. The parental hope experience is articulated in dealing with the uncertainty of information and diagnosis, an approach to which interaction with health professionals is a determinant and potentially distressful element. Hope was identified as one of the determinants of coping and, consequently, linked to autonomy and parenthood. Cognitive and affiliative dimensions were the hope dimensions that predominated in the results, which corresponded to the parents’ ability to formulate realistic goals and meaningful interpersonal relationships, respectively. Conclusion Hope is a force capable of guiding parents along the path of uncertainties experienced through the diagnosis of a condition that compromises their child’s life. Health professionals can manage the family’s hope by establishing sensitive therapeutic relationships that focus on the dimension of hope. The need for advanced research and intervention in parental and family hope are some of the points made in this study. Protocol registration https://osf.io/u9xr5/ .

Although geometric shape content should be mastered by early high school, many pre-service teachers (PSTs), particularly those in elementary and special education, have limited yet deeply engrained shape concepts. This poses challenges for how to teach shape concepts in content courses for PSTs. Thus, this study tested an approach atypical for a content course. PSTs' positive perceptions of this 40-minute activity and the specific ways their content knowledge did and did not change were reported. The results could influence instruction of mathematics content courses for PSTs in powerful ways with minimal time as well as open research opportunities.

Summary: The nervous system of metazoans is involved in host-pathogen interactions to control immune activation. In Caenorhabditis elegans, this includes sleep induction, mediated by neuropeptide-like proteins (NLPs), which increases the chance of survival after wounding. Here we analyzed the role of NLP-27 in the infection of C. elegans with the nematode-trapping fungus Arthrobotrys flagrans. Early responses of C. elegans were the upregulation of nlp-27, the induction of paralysis (sleep), and neurodegeneration of the mechanosensing PVD (Posterior Ventral Process D) neurons. Deletion of nlp-27 reduced neurodegeneration during fungal attack. Induction of nlp-27 was independent of the MAP kinase PMK-1, and expression of nlp-27 in the hypodermis was sufficient to induce paralysis, although NLP-27 was also upregulated in head neurons. NLP-27 contains the pentapeptide YGGYG sequence known to bind the human μ- and κ-type opioid receptors suggesting NLP-27 or peptides thereof act on opioid receptors. The opioid receptor antagonist naloxone shortened the paralysis time like overexpression of NLP-27.

Justificativa e Objetivos: crianças ainda são afetadas pelo HIV e pela tuberculose (TB). Dessa forma, o objetivo do estudo foi identificar a ocorrência de casos de HIV e TB em crianças. Métodos: trata-se de estudo epidemiológico, não experimental, retrospectivo, em que a população foi constituída pelo registro de casos infantis de HIV e TB residentes em um município do interior do estado de São Paulo, no período de 2012 a 2022, na faixa etária de zero a 13 anos de idade. Após a coleta de dados, foi realizada a verificação de consistência e validade dos dados, seguida do tratamento categorizado das informações para análises descritivas e apresentação em tabelas de frequência absoluta e relativa. Resultados: no período de estudo, foram identificados seis casos de HIV e sete de TB em crianças com média anual respectiva de 0,033 e 0,031 casos/1.000 habitantes com idade até 13 anos. Verificaram-se 146 notificações de criança exposta ao HIV. Houve diferença de meses a anos entre as datas de diagnóstico e de notificação, o que diverge do recomendado pelo Ministério da Saúde. Foi verificada a incompatibilidade entre plataformas de registro de âmbito municipal e estadual, o que evidencia uma quebra do fluxo de informação das notificações. Conclusão: houve ocorrência de casos de HIV e TB infantil nos últimos dez anos. Foram identificados problemas estruturais na fragmentação do fluxo da informação que subsidia ações de saúde de acordo com as necessidades da população, o que ofusca a capacidade de resposta do sistema de saúde.

Resumo Objetivo Construir e validar o conteúdo de um bundle para quantificação da perda sanguínea pós-parto vaginal. Métodos Estudo metodológico desenvolvido de fevereiro a agosto de 2022, em três etapas: levantamento bibliográfico, construção do instrumento e validação de conteúdo por 14 experts. O instrumento para validação foi composto por 11 itens selecionados a partir de revisão sistemática. Para cada item do bundle aplicou-se escala Likert e para verificar a concordância entre experts, calculou-se o Índice de Concordância. Consideraram-se válidos os itens com concordância acima de 80%. A validação de conteúdo foi realizada em uma única rodada de avaliação. Resultados A versão final do bundle foi composta por nove itens. Os cuidados propostos estão relacionados à quantificação direta do sangramento pós-parto e seu registro, observação da puérpera, a utilização de protocolos institucionais em casos de hemorragia pós-parto, assim como a capacitação da equipe. Conclusão O estudo permitiu construir e validar bundle para quantificação da perda sanguínea pós-parto vaginal, com vistas à melhora do diagnóstico de hemorragia pós-parto.

Hard X-ray spectroscopy is an element specific probe of electronic state, but signals are weak and require intense light to study low concentration samples. Free electron laser facilities offer the highest intensity X-rays of any available light source. The light produced at such facilities is stochastic, with spikey, broadband spectra that change drastically from shot to shot. Here, using aqueous ferrocyanide, we show that the resonant X-ray emission (RXES) spectrum can be inferred by correlating for each shot the fluorescence intensity from the sample with spectra of the fluctuating, self-amplified spontaneous emission (SASE) source. We obtain resolved narrow and chemically rich information in core-to-valence transitions of the pre-edge region at the Fe K-edge. Our approach avoids monochromatization, provides higher photon flux to the sample, and allows non-resonant signals like elastic scattering to be simultaneously recorded. The spectra obtained match well with spectra measured using a monochromator. We also show that inaccurate measurements of the stochastic light spectra reduce the measurement efficiency of our approach.

We determine the pathways in the photo-dissociation reactions of Fe(CO)5 both in the gas phase and in solution by mapping the valence electronic structure of the reaction intermediates with femtosecond X-ray laser spectroscopy.

Time and energy resolved photoelectron distributions of photo-excited Nal are presented. A splitting in the photo-excited state suggested by calculations of the intramolecular potential energy surfaces could be confirmed experimentally for the first time.

ABSTRACT Objective: to identify factors associated with fear of COVID-19 among women who experienced pregnancy or childbirth during the pandemic. Methods: a cross-sectional study, nested within a prospective cohort, using an online survey, from August 2021 to February 2022, based on descriptive data analysis. Results: of the 431 participants, 52.8% were postpartum women and 20.1% were pregnant women. With regard to fear of COVID-19, a mean score of 20.46 was obtained (moderate fear). The highest fear scores were present in women whose newborns were admitted to hospital in neonatal critical units (p=0.032), and the lowest among those covered by supplementary health (insurance) (p=0.016). Conclusion: among pregnant and postpartum women, high fear of COVID-19 translated into the possibility of having newborns admitted to hospital in a critical unit. The importance of supporting actions to support pregnant/postpartum women’s mental health in relation to COVID-19 or other threats that may influence the neonatal outcome stands out.

ABSTRACT Objective: to compare the effectiveness of different diagnostic methods to estimate postpartum blood volume loss. Methods: a systematic review of effectiveness according to PRISMA and JBI Protocol. Searches in PubMed/MEDLINE, LILACS, Scopus, Embase, Web of Science and CINAHL, with descriptor “Postpartum Hemorrhage” associated with keyword “Quantification of Blood Loss”. Tabulated extracted data, presented in metasynthesis and meta-analysis was applied to quantitative data. To assess risk of bias, JBI Appraisal Tools were applied. Results: fourteen studies were included, published between 2006 and 2021. Quantification of loss by any method was superior to visual estimation and is highly recommended, however the studies’ high heterogeneity did not allow estimating this association. Conclusion: the studies’ high heterogeneity, with a probable margin of error given the uncontrolled factors, indicates the need for further studies, however quantification proved to be effective in relation to visual estimate. PROSPERO registration CRD 42021234486.

The metal centres in metalloenzymes and molecular catalysts are responsible for the rearrangement of atoms and electrons during complex chemical reactions, and they enable selective pathways of charge and spin transfer, bond breaking/making and the formation of new molecules. Mapping the electronic structural changes at the metal sites during the reactions gives a unique mechanistic insight that has been difficult to obtain to date. The development of X-ray free-electron lasers (XFELs) enables powerful new probes of electronic structure dynamics to advance our understanding of metalloenzymes. The ultrashort, intense and tunable XFEL pulses enable X-ray spectroscopic studies of metalloenzymes, molecular catalysts and chemical reactions, under functional conditions and in real time. In this Technical Review, we describe the current state of the art of X-ray spectroscopy studies at XFELs and highlight some new techniques currently under development. With more XFEL facilities starting operation and more in the planning or construction phase, new capabilities are expected, including high repetition rate, better XFEL pulse control and advanced instrumentation. For the first time, it will be possible to make real-time molecular movies of metalloenzymes and catalysts in solution, while chemical reactions are taking place.

Abstract Background The miR-200c/141 cluster has recently been implicated in the epithelial to mesenchymal transition (EMT) process. The expression of these two miRNAs is inversely correlated with tumorigenicity and invasiveness in several human cancers. The role of these miRNAs in cancer progression is based in part on their capacity to target the EMT activators ZEB1 and ZEB2, two transcription factors, which in turn repress expression of E-cadherin. Little is known about the regulation of the mir200c/141 cluster, whose targeting has been proposed as a promising new therapy for the most aggressive tumors. Findings We show that the miR-200c/141 cluster is repressed by DNA methylation of a CpG island located in the promoter region of these miRNAs. Whereas in vitro methylation of the miR-200c/141 promoter led to shutdown of promoter activity, treatment with a demethylating agent caused transcriptional reactivation in breast cancer cells formerly lacking expression of miR-200c and miR-141. More importantly, we observed that DNA methylation of the identified miR-200c/141 promoter was tightly correlated with phenotype and the invasive capacity in a panel of 8 human breast cancer cell lines. In line with this, in vitro induction of EMT by ectopic expression of the EMT transcription factor Twist in human immortalized mammary epithelial cells (HMLE) was accompanied by increased DNA methylation and concomitant repression of the miR-200c/141 locus. Conclusions The present study demonstrates that expression of the miR-200c/141 cluster is regulated by DNA methylation, suggesting epigenetic regulation of this miRNA locus in aggressive breast cancer cell lines as well as untransformed mammary epithelial cells. This epigenetic silencing mechanism might represent a novel component of the regulatory circuit for the maintenance of EMT programs in cancer and normal cells.

Accurate computations of experimental observables are essential for interpreting the high information content held within x-ray spectra. However, for complicated systems this can be difficult, a challenge compounded when dynamics becomes important owing to the large number of calculations required to capture the time-evolving observable. While machine learning architectures have been shown to represent a promising approach for rapidly predicting spectral lineshapes, achieving simultaneously accurate and sufficiently comprehensive training data is challenging. Herein, we introduce Δ-learning for x-ray spectroscopy. Instead of directly learning the structure-spectrum relationship, the Δ-model learns the structure dependent difference between a higher and lower level of theory. Consequently, once developed these models can be used to translate spectral shapes obtained from lower levels of theory to mimic those corresponding to higher levels of theory. Ultimately, this achieves accurate simulations with a much reduced computational burden as only the lower level of theory is computed, while the model can instantaneously transform this to a spectrum equivalent to a higher level of theory. Our present model, demonstrated herein, learns the difference between TDDFT(BLYP) and TDDFT(B3LYP) spectra. Its effectiveness is illustrated using simulations of Rh L3-edge spectra tracking the C–H activation of octane by a cyclopentadienyl rhodium carbonyl complex.

We present an RGBD infant head reconstruction method with a mobile phone depth sensor on a novel dataset. Acquiring 3D models from infants enables many important medical tasks such as automatic cranial asymmetry classification for plagiocephaly therapy progress estimation. Existing methods for 3D infant head reconstruction employ synchronized multi-view configurations or hand-held laser scanning methods making their widespread employment difficult. In contrast, RGBD reconstruction methods either rely on static scenes failing on this task due to rapid infant head movements or employ dynamic methods lacking the high fidelity surface reconstructions required for accurate cranial measurements. We propose a domain-specific 3D reconstruction method augmenting static RGBD methods focusing on the rigid parts of the head and exploiting scene knowledge about the data acquisition methodology. We evaluate our approach using provided ground truth anthropometric measurements of the biparietal diameter and report competitive accuracy.

Resumo Objetivo conhecer e analisar as vivências de mães no cuidado a crianças e adolescentes com Epidermólise Bolhosa. Método estudo descritivo de abordagem qualitativa desenvolvido junto a dez mães de crianças e adolescentes com Epidermólise Bolhosa de diferentes regiões do Brasil, a partir de entrevistas semiestruturadas, áudio e vídeo gravadas, por via remota, utilizando-se a plataforma Google Meet®, entre setembro e novembro de 2021. A técnica da análise temática direcionou a apreciação do material empírico. Resultados participaram do estudo mães com idade entre 23 e 53 anos. Duas categorias traduzem a vivência materna: i) O “baque” do diagnóstico e os desafios iniciais e ii) “Deixar de viver para viver para ele”: as mudanças no cotidiano das famílias. Considerações finais e implicações para a prática as mães vivenciaram sentimentos de medo e insegurança diante do diagnóstico do filho e a rotina de cuidados, em especial, as trocas diárias de curativos, acarretaram sobrecarga física e emocional. Esses resultados podem subsidiar o acompanhamento dessas famílias de modo a instrumentalizá-las para o cuidado e apoiá-las emocionalmente.

Transition metals in inorganic systems and metalloproteins can occur in different oxidation states, which makes them ideal redox-active catalysts. To gain a mechanistic understanding of the catalytic reactions, knowledge of the oxidation state of the active metals, ideally in operando, is therefore critical. L-edge X-ray absorption spectroscopy (XAS) is a powerful technique that is frequently used to infer the oxidation state via a distinct blue shift of L-edge absorption energies with increasing oxidation state. A unified description accounting for quantum-chemical notions whereupon oxidation does not occur locally on the metal but on the whole molecule and the basic understanding that L-edge XAS probes the electronic structure locally at the metal has been missing to date. Here we quantify how charge and spin densities change at the metal and throughout the molecule for both redox and core-excitation processes. We explain the origin of the L-edge XAS shift between the high-spin complexes MnII(acac)2 and MnIII(acac)3 as representative model systems and use ab initio theory to uncouple effects of oxidation-state changes from geometric effects. The shift reflects an increased electron affinity of MnIII in the core-excited states compared to the ground state due to a contraction of the Mn 3d shell upon core-excitation with accompanied changes in the classical Coulomb interactions. This new picture quantifies how the metal-centered core hole probes changes in formal oxidation state and encloses and substantiates earlier explanations. The approach is broadly applicable to mechanistic studies of redox-catalytic reactions in molecular systems where charge and spin localization/delocalization determine reaction pathways.

X-ray absorption spectroscopy at the L-edge of 3d transition metals is widely used for probing the valence electronic structure at the metal site via 2p-3d transitions. Assessing the information contained in L-edge absorption spectra requires systematic comparison of experiment and theory. We here investigate the Cr L-edge absorption spectrum of high-spin chromium acetylacetonate CrIII(acac)3 in solution. Using a transmission flatjet enables determining absolute absorption cross sections and spectra free from X-ray-induced sample damage. We address the challenges of measuring Cr L absorption edges spectrally close to the O K absorption edge of the solvent. We critically assess how experimental absorption cross sections can be used to extract information on the electronic structure of the studied system by comparing our results of this CrIII (3d3) complex to our previous work on L-edge absorption cross sections of MnIII(acac)3 (3d4) and MnII(acac)2 (3d5). Considering our experimental uncertainties, the most insightful experimental observable for this d3(CrIII)-d4(MnIII)-d5(MnII) series is the L-edge branching ratio, and we discuss it in comparison to semiempirical multiplet theory and ab initio restricted active space calculations. We further discuss and analyze trends in integrated absorption cross sections and correlate the spectral shapes with the local electronic structure at the metal sites.

X-ray induced sample damage can impede electronic and structural investigations of radiation-sensitive samples studied with X-rays. Here we quantify dose-dependent sample damage to the prototypical MnIII(acac)3 complex in solution and at room temperature for the soft X-ray range, using X-ray absorption spectroscopy at the Mn L-edge. We observe the appearance of a reduced MnII species as the X-ray dose is increased. We find a half-damage dose of 1.6 MGy and quantify a spectroscopically tolerable dose on the order of 0.3 MGy (1 Gy = 1 J kg-1), where 90% of MnIII(acac)3 are intact. Our dose-limit is around one order of magnitude lower than the Henderson limit (half-damage dose of 20 MGy) which is commonly employed for protein crystallography with hard X-rays. It is comparable, however, to the dose-limits obtained for collecting un-damaged Mn K-edge spectra of the photosystem II protein, using hard X-rays. The dose-dependent reduction of MnIII observed here for solution samples occurs at a dose limit that is two to four orders of magnitude smaller than the dose limits previously reported for soft X-ray spectroscopy of iron samples in the solid phase. We compare our measured to calculated spectra from ab initio restricted active space (RAS) theory and discuss possible mechanisms for the observed dose-dependent damage of MnIII(acac)3 in solution. On the basis of our results, we assess the influence of sample damage in other experimental studies with soft X-rays from storage-ring synchrotron radiation sources and X-ray free-electron lasers.

The 3d transition metals play a pivotal role in many charge transfer processes in catalysis and biology. X-ray absorption spectroscopy at the L-edge of metal sites probes metal 2p-3d excitations, providing key access to their valence electronic structure, which is crucial for understanding these processes. We report L-edge absorption spectra of MnII(acac)2 and MnIII(acac)3 complexes in solution, utilizing a liquid flatjet for X-ray absorption spectroscopy in transmission mode. With this, we derive absolute absorption cross-sections for the L-edge transitions with peak magnitudes as large as 12 and 9 Mb for MnII(acac)2 and MnIII(acac)3, respectively. We provide insight into the electronic structure with ab initio restricted active space calculations of these L-edge transitions, reproducing the experimental spectra with excellent agreement in terms of shapes, relative energies, and relative intensities for the two complexes. Crystal field multiplet theory is used to assign spectral features in terms of the electronic structure. Comparison to charge transfer multiplet calculations reveals the importance of charge transfer in the core-excited final states. On the basis of our experimental observations, we extrapolate the feasibility of 3d transition metal L-edge absorption spectroscopy using the liquid flatjet approach in probing highly dilute biological solution samples and possible extensions to table-top soft X-ray sources.

Resumo Objetivo: identificar o perfil das gestações e prevalência de adesão à consulta puerperal entre puérperas adolescentes comparadas a não adolescentes, assistidas em um ambulatório de hospital de ensino do interior de Minas Gerais. Método: estudo transversal aninhado a uma coorte de puérperas; amostra não probabilística, por conveniência; gestação na adolescência - variável dependente; sociodemográficas, clínicas e obstétricas - variáveis independentes. Utilizado instrumento próprio, testado mediante piloto. Calculadas razões de prevalência e intervalos de confiança; aplicados testes qui-quadrado e exato de Fisher, considerando nível de significância de 5%, e regressão de Poisson com variância robusta. Resultados: entrevistadas 121 puérperas, 18,2% (22) adolescentes, verificou-se entre elas baixa escolaridade (p

X-ray absorption spectroscopy at the L-edge of 3d transition metals provides unique information on the local metal charge and spin states by directly probing 3d-derived molecular orbitals through 2p-3d transitions. However, this soft x-ray technique has been rarely used at synchrotron facilities for mechanistic studies of metalloenzymes due to the difficulties of x-ray-induced sample damage and strong background signals from light elements that can dominate the low metal signal. Here, we combine femtosecond soft x-ray pulses from a free-electron laser with a novel x-ray fluorescence-yield spectrometer to overcome these difficulties. We present L-edge absorption spectra of inorganic high-valent Mn complexes (Mn ∼ 6-15 mmol/l) with no visible effects of radiation damage. We also present the first L-edge absorption spectra of the oxygen evolving complex (Mn4CaO5) in Photosystem II (Mn

Light-induced oxidation of water by photosystem II (PS II) in plants, algae and cyanobacteria has generated most of the dioxygen in the atmosphere. PS II, a membrane-bound multi-subunit pigment protein complex, couples the one-electron photochemistry at the reaction centre with the four-electron redox chemistry of water oxidation at the Mn4CaO5 cluster in the oxygen-evolving complex (OEC). Under illumination, the OEC cycles through five intermediate S-states (S0 to S4), in which S1 is the dark-stable state and S3 is the last semi-stable state before O-O bond formation and O2 evolution. A detailed understanding of the O-O bond formation mechanism remains a challenge, and will require elucidation of both the structures of the OEC in the different S-states and the binding of the two substrate waters to the catalytic site. Here we report the use of femtosecond pulses from an X-ray free electron laser (XFEL) to obtain damage-free, room temperature structures of dark-adapted (S1), two-flash illuminated (2F; S3-enriched), and ammonia-bound two-flash illuminated (2F-NH3; S3-enriched) PS II. Although the recent 1.95 Å resolution structure of PS II at cryogenic temperature using an XFEL provided a damage-free view of the S1 state, measurements at room temperature are required to study the structural landscape of proteins under functional conditions, and also for in situ advancement of the S-states. To investigate the water-binding site(s), ammonia, a water analogue, has been used as a marker, as it binds to the Mn4CaO5 cluster in the S2 and S3 states. Since the ammonia-bound OEC is active, the ammonia-binding Mn site is not a substrate water site. This approach, together with a comparison of the native dark and 2F states, is used to discriminate between proposed O-O bond formation mechanisms.

ABSTRACT Signaling of two-component systems by phosphoryl transfer requires interaction of the sensor kinase with the response regulator. Interaction of the C4-dicarboxylate-responsive and membrane-integral sensor kinase DcuS with the response regulator DcuR was studied. In vitro, the cytoplasmic part of DcuS (PASC-Kin) was employed. Stable complexes were formed, when either DcuS or DcuR were phosphorylated (Kd 22 ± 11 and 28 ± 7 nM, respectively). The unphosphorylated proteins produced a more labile complex (Kd 1380 ± 395 nM). Bacterial two-hybrid studies confirm interaction of DcuR with DcuS (and PASC-Kin) in vivo. The absolute contents of DcuR (197-979 pmol mg−1 protein) in the bacteria exceeded those of DcuS by more than 1 order of magnitude. According to the Kd values, DcuS exists in complex, with phosphorylated but also unphosphorylated DcuR. In live cell imaging, the predominantly freely diffusing DcuR becomes markedly less mobile after phosphorylation and activation of DcuS by fumarate. Portions of the low mobility fraction accumulated at the cell poles, the preferred location of DcuS, and other portions within the cell, representing phosphorylated DcuR bound to promoters. In the model, acitvation of DcuS increases the affinity toward DcuR, leading to DcuS-P × DcuR formation and phosphorylation of DcuR. The complex is stable enough for phosphate-transfer, but labile enough to allow exchange between DcuR from the cytosol and DcuR-P of the complex. Released DcuR-P diffuses to target promoters and binds. Uncomplexed DcuR-P in the cytosol binds to nonactivated DcuS and becomes dephosphorylated. The lower affinity between DcuR and DcuS avoids blocking of DcuS and allows rapid exchange of DcuR. IMPORTANCE Complex formation of membrane-bound sensor kinases with the response regulators represents an inherent step of signaling from the membrane to the promoters on the DNA. In the C4-dicarboxylate-sensing DcuS-DcuR two-component system, complex formation is strengthened by activation (phosphorylation) in vitro and in vivo, with trapping of the response regulator DcuR at the membrane. Single-molecule tracking of DcuR in the bacterial cell demonstrates two populations of DcuR with decreased mobility in the bacteria after activation: one at the membrane, but a second in the cytosol, likely representing DNA-bound DcuR. The data suggest a model with binding of DcuR to DcuS-P for phosphorylation, and of DcuR-P to DcuS for dephosphorylation, allowing rapid adaptation of the DcuR phosphorylation state. DcuR-P is released and transferred to DNA by 3D diffusion.

X-ray free electron lasers (XFELs) enable unprecedented new ways to study the electronic structure and dynamics of transition metal systems. L-edge absorption spectroscopy is a powerful technique for such studies and the feasibility of this method at XFELs for solutions and solids has been demonstrated. However, the required x-ray bandwidth is an order of magnitude narrower than that of self-amplified spontaneous emission (SASE), and additional monochromatization is needed. Here we compare L-edge x-ray absorption spectroscopy (XAS) of a prototypical transition metal system based on monochromatizing the SASE radiation of the linac coherent light source (LCLS) with a new technique based on self-seeding of LCLS. We demonstrate how L-edge XAS can be performed using the self-seeding scheme without the need of an additional beam line monochromator. We show how the spectral shape and pulse energy depend on the undulator setup and how this affects the x-ray spectroscopy measurements.

Color and polarization provide complementary information about the world and are detected by specialized photoreceptors. However, the downstream neural circuits that process these distinct modalities are incompletely understood in any animal. Using electron microscopy, we have systematically reconstructed the synaptic targets of the photoreceptors specialized to detect color and skylight polarization in Drosophila, and we have used light microscopy to confirm many of our findings. We identified known and novel downstream targets that are selective for different wavelengths or polarized light, and followed their projections to other areas in the optic lobes and the central brain. Our results revealed many synapses along the photoreceptor axons between brain regions, new pathways in the optic lobes, and spatially segregated projections to central brain regions. Strikingly, photoreceptors in the polarization-sensitive dorsal rim area target fewer cell types, and lack strong connections to the lobula, a neuropil involved in color processing. Our reconstruction identifies shared wiring and modality-specific specializations for color and polarization vision, and provides a comprehensive view of the first steps of the pathways processing color and polarized light inputs.