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Plants have several mechanisms to adapt or acclimate to environmental stress. Morphological, physiological, or genetic changes are examples of complex plant responses. In recent years, our understanding of the role of epigenetic regulation, which encompasses changes that do not alter the DNA sequence, as an adaptive mechanism in response to stressful conditions has advanced significantly. Some studies elucidated and synthesized epigenetic mechanisms and their relationships with environmental change, while others explored the interplay between epigenetic modifications and environmental shifts, aiming to deepen our understanding of these complex processes. In this study, we performed a systematic review of the literature to analyze the progression of epigenetics studies on plant species' responses to abiotic factors. We also aimed to identify the most studied species, the type of abiotic factor studied, and the epigenetic technique most used in the scientific literature. For this, a search for articles in databases was carried out, and after analyzing them using pre-established inclusion criteria, a total of 401 studies were found. The most studied species were Arabidopsis thaliana and Oryza sativa, highlighting the gap in studies of non-economic and tropical plant species. Methylome DNA sequencing is the main technique used for the detection of epigenetic interactions in published studies. Furthermore, most studies sought to understand the plant responses to abiotic changes in temperature, water, and salinity. It is worth emphasizing further research is necessary to establish a correlation between epigenetic responses and abiotic factors, such as extreme temperatures and light, associated with climate change.
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We study the glass transition by exploring a broad class of kinetic rules that can significantly modify the normal dynamics of supercooled liquids while maintaining thermal equilibrium. Beyond the usual dynamics of liquids, this class includes dynamics in which a fraction (1-f_{R}) of the particles can perform pairwise exchange or "swap moves," while a fraction f_{P} of the particles can move only along restricted directions. We find that (i) the location of the glass transition varies greatly but smoothly as f_{P} and f_{R} change and (ii) it is governed by a linear combination of f_{P} and f_{R}. (iii) Dynamical heterogeneities (DHs) are not governed by the static structure of the material; their magnitude correlates instead with the relaxation time. (iv) We show that a recent theory for temporal growth of DHs based on thermal avalanches holds quantitatively throughout the (f_{R},f_{P}) diagram. These observations are negative items for some existing theories of the glass transition, particularly those reliant on growing thermodynamic order or locally favored structure, and open new avenues to test other approaches, as we illustrate.
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It is known that diversity matters to improve scientific excellence and that scientific events are important occasions to discuss new ideas and create networks, beyond the fact that it helps to put the work of the scientists in evidence. Hence, increasing diversity in scientific events is crucial to improve their scientific quality and help to promote minorities. In Brazil, important physics scientific events are organized by the Brazilian Physical Society (SBF, in Portuguese), and in this work, some aspects related to the participation of women in these physics events are analyzed from 2005 to 2021. The analysis shows that women's participation has increased over the years, reaching in some areas of Physics the same percentage as the one observed in the SBF community (always below 25%). However, female participation as members of organizing committees and as keynote speakers is always lower. Some proposals are listed to change the current picture of inequality.
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Médicos , Física , Humanos , Femenino , Brasil , Sociedades , EtnicidadRESUMEN
The relation between wetting properties and geometric parameters of fractal surfaces are widely discussed on the literature and, however, there are still divergences on this topic. Here we propose a simple theoretical model to describe the wetting properties of a droplet of water placed on a hierarchical structured surface and test the predictions of the model and the dependence of the droplet wetting state on the initial conditions using simulation of the 3-spin Potts model. We show that increasing the auto-similarity level of the hierarchy - called n - does not affect considerably the stable wetting state of the droplet but increases its contact angle. Simulations also explicit the existence of metastable states on this type of surfaces and shows that, when n increases, the metastability becomes more pronounced. Finally we show that the fractal dimension of the surface is not a good predictor of the contact angle of the droplet.
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O presente artigo trata de discutir algumas questões referentes ao cenário social e político brasileiro. Ainda que esteja previsto em lei a universalidade de direitos, alguns grupos de pessoas são sistematicamente vulnerabilizados e excluídos, o que se complexifica a depender dos diferentes fatores que atravessam interseccionalmente seus corpos e experiências, entre eles, gênero, sexualidade, classe, raça, etnia. Essa situação se agrava com a ascensão de certos grupos e discursos, os quais discutimos três: conservadorismo, neopentecostalismo e neoliberalismo. Mesmo que eles sejam heterogêneos, guardando entre si diferenças importantes, atuam em conjunto em diversas circunstâncias. Apresentamos uma leitura desse cenário, estabelecendo relações entre os elementos apresentados que são produtores de subjetividades e de formas de relações específicas. (AU)
This article discusses some issues related to the Brazilian social and political scenario. Although the universality of rights is provided by law, some groups of people are systematically vulnerable and excluded, which becomes more complex depending on the different factors that intersecttheir bodies and experiences, including gender, sexuality, class, race, ethnicity. This situation worsens with the rise of certain groups and discourses, which we discuss three: conservatism, neopentecostalism and neoliberalism. Even though they are heterogeneous, keeping important differences between them, theywork together in different circumstances. We present a reading of this scenario, establishing relationships between the elements presented that are producers of subjectivities and forms of specific relationships. (AU)
Este artículo analiza algunos temas relacionados con el escenario social y político brasileño. Si bien la universalidad de los derechos está prevista por la ley, algunos grupos de personas son sistemáticamente vulnerablesy excluidos, lo que se vuelve más complejo en función de los diferentes factores que cruzan de manera intersectorial sus cuerpos y experiencias, entre ellos género, sexualidad, clase, raza, etnia. Esta situación se ve agravada por el surgimiento de ciertos grupos y discursos, de los que discutimos tres: conservadurismo, neopentecostalismo y neoliberalismo. Aunque son heterogéneos, con importantes diferencias entre ellos, actúan juntos en diferentes circunstancias. Presentamos una lectura de este escenario,estableciendo relaciones entre los elementos presentados que producen subjetividades y formas específicas de relación.(AU)
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BACKGROUND: Cardiovascular disease is the leading cause of death in Brazil and worldwide. In the context of diastolic dysfunction, echocardiography is the best non-invasive diagnostic method. However, the comparison of the two main guidelines for evaluate left ventricular diastolic function in acute coronary syndrome (ACS) is scarce. OBJECTIVE: To compare the prognostic value of both guidelines of American Society of Echocardiography, from 2009 and 2016, in patients with ACS. METHODS: This is a sub-analysis of a prospective cohort observational study with 109 patients admitted to the emergency with ACS. The follow up was performed within 1 year and combined outcome was cardiovascular death or new heart failure. We used the non-parametric Spearman method to assess the correlation between the categories of diastolic function according to the guideline used. The Cox model and the Log rank test with Kaplan-Meier curves were used to compare the prognostic value of categorizing patients according to the guideline used. The results were expressed as hazard ratio with a confidence interval of 95%. RESULTS: The mean age was 63 years ± 11, most male patients (73.4%) and the predominant color of patients was white (60.4%). Among the main risk factors, the most frequent for coronary artery disease was dyslipidemia (78%), followed by systemic arterial hypertension (77.1%) and sedentary lifestyle (65.9%). The study identified a mean borderline ejection fraction, a high E/E' ratio, and LV diastolic and systolic volumes presented means above normal. The most common electrocardiographic change on admission was T-wave inversion (45%), and NSTEMI was the main clinical diagnosis (74%). The categories in which there was a greater disagreement between the guidelines were grade II diastolic dysfunction and normal function. The correlation between the diagnosis of diastolic dysfunction when compared to the use of the 2009 and 2016 guidelines was weak (R = 0.56 by Spearman's method; p<0.001). By the Kaplan-Meier curves, dividing the groups into with or without LA pressure elevation, the distinction between the evolution of the two groups is significant when performed by the 2016 guideline (Log Rank = 8.17; p = 0.04). CONCLUSION: The current guideline (2016) for the assessment of left ventricular diastolic dysfunction showed a higher prognostic value of combined outcome of cardiovascular death or new heart failure within one year, when compared to the guideline of 2009 in patients.
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Modelos de Riesgos Proporcionales , Síndrome Coronario Agudo , Infarto del Miocardio sin Elevación del ST , Insuficiencia Cardíaca , Factores de RiesgoRESUMEN
BACKGROUND: Human milk is the best food for infants; however, when breastfeeding is not possible, pasteurized milk from human milk banks is the best alternative. Little has been reported about variations in the bacterial microbiota composition of human milk after pasteurization. RESEARCH AIM: To characterize and compare the bacterial microbiota composition and diversity within human milk among Mexican mothers before and after the Holder pasteurization process. METHODS: A cross-sectional, observational, and comparative design was used. The effect of the pasteurization process on the bacterial composition and diversity of human milk samples of donors (N = 42) from a public milk bank was assessed before and after pasteurization by high throughput deoxyribonucleic acid sequencing of V3-16S rRNA gene libraries. Sequencing data were examined using the Quantitative Insights into Microbial Ecology software and Phyloseq in R environment. RESULTS: A varied community of bacteria was found in both raw and pasteurized human milk. The bacterial diversity of the milk samples was increased by the pasteurization, where some thermoduric bacteria of the phyla Proteobacteria, Firmicutes, and Actinobacteria were more abundant. The source tracker analysis indicated that at most 1.0% of bacteria may have come from another source, showing the safety of the process used to treat milk samples. CONCLUSION: The pasteurization process increased the bacterial diversity. We selected taxa capable of surviving the process, which could proliferate after the treatment without being a risk for infants.
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Microbiota , Bancos de Leche Humana , Bacterias/genética , Lactancia Materna , Estudios Transversales , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Microbiota/genética , Leche Humana/microbiología , Pasteurización , ARN Ribosómico 16S/genéticaRESUMEN
Host genetics are important to consider in the role of resistance or susceptibility for developing active pulmonary tuberculosis (TB). Several association studies have reported the role of variants in STAT4 and TRAF1/C5 as risk factors to autoimmune diseases. Nevertheless, more data is needed to elucidate the role of these gene variants in infectious disease. Our data reports for the first time, variant rs10818488 in the TRAF1/C5 gene (found 47% of the population worldwide), is associated with susceptibility (OR = 1.51) to development TB. Multivariate analysis evidenced association between rs10818488 TRAF1/C5 and risk to multibacillary TB (OR = 4.18), confers increased bacteria load in the lung, indicates a decreased ability to control pathogen levels in the lung, and spread of the pathogen to new hosts. We showed that the "loss-of-function" variant in TRAF1/C5 led to susceptibility for TB by decreased production of TNF-α. Our results suggest the role of variant TRAF1/C5 in susceptibility to TB as well as in clinical presentation of multibacillary TB.
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Factor 1 Asociado a Receptor de TNF , Tuberculosis Pulmonar , Complemento C5 , Predisposición Genética a la Enfermedad , Humanos , Pulmón/metabolismo , Polimorfismo de Nucleótido Simple , Factor 1 Asociado a Receptor de TNF/genética , Factor 1 Asociado a Receptor de TNF/metabolismo , Tuberculosis Pulmonar/genética , Factor de Necrosis Tumoral alfa/genéticaRESUMEN
Several oil-water separation techniques have been proposed to improve the capacity of cleaning water. With the technological possibility of producing materials with antagonist wetting behavior, for example, a substrate that repels water and absorbs oil, the understanding of the properties that control this selective capacity has increased with the goal of being used as the mechanism to separate mixed liquids. Besides the experimental advance in this field, less is known from the theoretical side. In this work, we propose a theoretical model to predict the wetting properties of a given substrate and introduce simulations with a four-spin cellular Potts model to study its efficiency in separating water from oil. Our results show that the efficiency of the substrates depends both on the interaction between the liquids and on the wetting behavior of the substrates itself. The water behavior of the droplet composed of both liquids is roughly controlled by the hydrophobicity of the substrate. Predicting the oil behavior, however, is more complex because the substrate being oleophilic does not guarantee that the total amount of oil present on the droplet will be absorbed by the substrate. For both types of substrates considered in this work, pillared and porous with a reservoir, there is always an amount of reminiscent oil on the droplet, which is not absorbed by the substrate due to the interaction with the water and the gas. Both theoretical and numerical models can be easily modified to analyze other types of substrates and liquids.
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BACKGROUND: The incidence of totally implantable catheter fracture ranges from 0.48% to 5.00%, and these fractures represent a potentially fatal complication. The fracture mechanism of catheters implanted via the jugular vein is unclear, and whether extreme arm movements represent an additional risk factor for repetitive stress of the material remains unknown. The aim of this study was to demonstrate and classify catheter deformations caused by extreme arm mobilization and associations with changes in catheter function and displacement. METHODS: We analyzed the fluoroscopy images of 60 consecutive patients undergoing long-term indwelling port implantation via the jugular vein. Three images were taken: arm in maximal abduction, maximal frontal elevation, and maximal adduction. The images were compared with an image of the remainder of the arm. We analyzed three catheter regions to classify the deformity: A, connection between catheter and reservoir; B, the catheter's subcutaneous tunnel; and C, the catheter's entrance in the jugular vein. The deformations were classified in comparative manner as follows: 0 (no changes), 1 (minor changes, new slightly curvatures with an angle of >90°), and 2 (major changes, new severe curvatures with angles of ≤90°). In each position, catheter function (injection and aspiration) and displacement of the reservoir and tip were analyzed. RESULTS: Only 15% of patients did not show a deformity; 33.3% had a deformity in only one position, 47.7% in two positions, and 10% in three positions. Minor deformities were observed in 70% of patients and major deformities in 40%. Moreover, 25% of patients presented both major and minor deformities. Major deformities were observed in 25.0% of patients on maximal frontal elevation, in 23.3% on maximal adduction and in none on maximal abduction. Region B was the most affected, with 57.8% of all minor deformities and 78.1% of all major deformities. No change in function was noted in 91.7% of the catheters. Maximal arm adduction resulted in greater vertical and horizontal displacement of the catheter tip and horizontal displacement of the reservoir. Higher body mass index values were associated with major deformities. CONCLUSIONS: Maximal frontal elevation and maximal adduction were associated with major catheter deformities, and the subcutaneous tunnel region was the most deformed catheter region. An association between major catheter deformity and high body mass index was noted; in contrast, no association between the severity of catheter deformity, tip or reservoir displacement, or worsened functioning was observed.
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Brazo/fisiología , Catéteres de Permanencia , Catéteres Venosos Centrales , Falla de Equipo , Venas Yugulares , Movimiento , Adulto , Anciano , Anciano de 80 o más Años , Cateterismo Venoso Central , Femenino , Fluoroscopía , Humanos , Venas Yugulares/diagnóstico por imagen , Venas Yugulares/cirugía , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Adulto JovenRESUMEN
We introduce a new model to study the effect of surface roughness on the jamming transition. By performing numerical simulations, we show that for a smooth surface, the jamming transition density and the contact number at the transition point both increase upon increasing asphericity, as for ellipsoids and spherocylinders. Conversely, for a rough surface, both quantities decrease, in quantitative agreement with the behavior of frictional particles. Furthermore, in the limit corresponding to the Coulomb friction law, the model satisfies a generalized isostaticity criterion proposed in previous studies. We introduce a counting argument that justifies this criterion and interprets it geometrically. Finally, we propose a simple theory to predict the contact number at finite friction from the knowledge of the force distribution in the infinite friction limit.
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BACKGROUND: The effects of HIV and antiretroviral therapy on cardiovascular system of perinatally infected children throughout their development are not fully understood. OBJECTIVES: To determine the prevalence of cardiac abnormalities in a retrospective cohort of perinatally HIV-infected patients and to investigate associations between echocardiographic and clinical data during their follow-up. METHODS: Review of medical records and echocardiogram reports of 148 perinatally HIV-infected patients between January 1991 and December 2015. RESULTS: Four hundred and eighty echocardiograms were analyzed and 46 (31%) patients showed cardiac abnormalities, frequently subclinical and transient. Nadir CD4 count was higher in patients with consistently normal echocardiogram: 263 (4-1480) versus 202 (5-1746) cells/µL, P = 0.021. Right ventricular (RV) dilation was detected in 18.9%, left ventricular (LV) dilation in 21.6%, septal hypertrophy in 12.2%, LV posterior wall hypertrophy in 6%, LV systolic dysfunction in 8% and pulmonary hypertension in 8.7% of patients. Opportunistic infections were associated with RV dilation [odds ratio (OR = 4.34; 1.78-10.53; P < 0.01)], pulmonary hypertension (OR = 8.78; 2.80-27.51; P < 0.01) and LV systolic dysfunction (OR = 5.38; 1.55-18.71; P < 0.01). Longer duration of highly active antiretroviral therapy was associated with reduced risk of LV dilation (OR = 0.91; 0.85-0.97; P < 0.01) and systolic dysfunction (OR = 0.71; 0.59-0.85; P < 0.01). Protease inhibitors use was associated with reduced risk of RV dilation (OR = 0.54; 0.30-0.97; P < 0.05), LV dilation (OR = 0.35; 0.21-0.60; P < 0.01) and LV systolic dysfunction (OR = 0.07; 0.02-0.31; P < 0.01). Higher CD4 count was associated with lower risk of LV systolic dysfunction (OR = 0.82; 0.69-0.98; P < 0.05). CONCLUSIONS: Echocardiograms identified cardiac abnormalities among children with perinatally acquired HIV infection, and data suggest that immunologic status and therapeutic strategies throughout development can influence cardiac disease burden in this population.
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Terapia Antirretroviral Altamente Activa/efectos adversos , Sistema Cardiovascular/fisiopatología , Ecocardiografía , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Cardiopatías/etiología , Adolescente , Brasil/epidemiología , Recuento de Linfocito CD4 , Sistema Cardiovascular/efectos de los fármacos , Niño , Preescolar , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Estudios Longitudinales , Masculino , Registros Médicos , Atención Perinatal , Estudios RetrospectivosRESUMEN
In allosteric proteins, the binding of a ligand modifies function at a distant active site. Such allosteric pathways can be used as target for drug design, generating considerable interest in inferring them from sequence alignment data. Currently, different methods lead to conflicting results, in particular on the existence of long-range evolutionary couplings between distant amino-acids mediating allostery. Here we propose a resolution of this conundrum, by studying epistasis and its inference in models where an allosteric material is evolved in silico to perform a mechanical task. We find in our model the four types of epistasis (Synergistic, Sign, Antagonistic, Saturation), which can be both short or long-range and have a simple mechanical interpretation. We perform a Direct Coupling Analysis (DCA) and find that DCA predicts well the cost of point mutations but is a rather poor generative model. Strikingly, it can predict short-range epistasis but fails to capture long-range epistasis, in consistence with empirical findings. We propose that such failure is generic when function requires subparts to work in concert. We illustrate this idea with a simple model, which suggests that other methods may be better suited to capture long-range effects.
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Sitio Alostérico/genética , Biología Computacional/métodos , Epistasis Genética/genética , Regulación Alostérica/fisiología , Aminoácidos/genética , Animales , Dominio Catalítico/fisiología , Simulación por Computador , Diseño de Fármacos , Humanos , Ligandos , Modelos Moleculares , Modelos Teóricos , Conformación Proteica , Proteínas/químicaRESUMEN
In allosteric proteins, binding a ligand can affect function at a distant location, for example, by changing the binding affinity of a substrate at the active site. The induced fit and population shift models, which differ by the assumed number of stable configurations, explain such cooperative binding from a thermodynamic viewpoint. Yet, understanding what mechanical principles constrain these models remains a challenge. Here, we provide an empirical study on 34 proteins supporting the idea that allosteric conformational change generally occurs along a soft elastic mode presenting extended regions of high shear. We argue, based on a detailed analysis of how the energy profile along such a mode depends on binding, that in the induced fit scenario, there is an optimal stiffness ka∗ â¼ 1/N for cooperative binding, where N is the number of residues. We find that the population shift scenario is more robust to mutations affecting stiffness because binding becomes more and more cooperative with stiffness up to the same characteristic value ka∗, beyond which cooperativity saturates instead of decaying. We numerically confirm these findings in a nonlinear mechanical model. Dynamical considerations suggest that a stiffness of order ka∗ is favorable in that scenario as well, supporting that for proper function, proteins must evolve a functional elastic mode that is softer as their size increases. In consistency with this view, we find a fair anticorrelation between the stiffness of the allosteric response and protein size in our data set.
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Modelos Moleculares , Regulación Alostérica , Sitios de Unión , Conformación Molecular , TermodinámicaRESUMEN
It is well established that roughness and chemistry play a crucial role in the wetting properties of a substrate. Yet, few studies have analyzed systematically the effect of the nonuniformity in the distribution of texture and surface tension of substrates on its wetting properties. In this work we investigate this issue theoretically and numerically. We propose a continuous model that takes into account the total energy required to create interfaces of a droplet in two possible wetting states: Cassie-Baxter (CB) with air pockets trapped underneath the droplet; and the other characterized by the homogeneous wetting of the surface, called the Wenzel (W) state. To introduce geometrical nonregularity we suppose that pillar heights and pillar distances are Gaussian distributed instead of having a constant value. Similarly, we suppose a heterogeneous distribution of Young's angle on the surface to take into account the chemical nonuniformity. This allows to vary the "amount" of disorder by changing the variance of the distribution. We first solve this model analytically and then we also propose a numerical version of it, which can be applied to study any type of disorder. In both versions, we employ the same physical idea: The energies of both states are minimized to predict the thermodynamic wetting state of the droplet for a given volume and surface texture. We find that the main effect of disorder is to induce the stability of both wetting states on the same substrate. In terms of the influence of the disorder on the contact angle of the droplet, we find that it is negligible for the chemical disorder and for pillar-distance disorder. However, in the case of pillar-height disorder, it is observed that the average contact angle of the droplet increases with the amount of disorder. We end the paper investigating how the region of stability of both wetting states behaves when the droplet volume changes.
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We present a model and protocol that enable the generation of extremely stable computer glasses at minimal computational cost. The protocol consists of an instantaneous quench in an augmented potential energy landscape, with particle radii as additional degrees of freedom. We demonstrate how our glasses' mechanical stability, which is readily tunable in our approach, is reflected in both microscopic and macroscopic observables. Our observations indicate that the stability of our computer glasses is at least comparable to that of computer glasses generated by the celebrated Swap Monte Carlo algorithm. Strikingly, some key properties support even qualitatively enhanced stability in our scheme: the density of quasilocalized excitations displays a gap in our most stable computer glasses, whose magnitude scales with the polydispersity of the particles. We explain this observation, which is consistent with the lack of plasticity we observe at small stress. It also suggests that these glasses are depleted from two-level systems, similarly to experimental vapor-deposited ultrastable glasses.
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Allosteric regulation plays an important role in many biological processes, such as signal transduction, transcriptional regulation, and metabolism. Allostery is rooted in the fundamental physical properties of macromolecular systems, but its underlying mechanisms are still poorly understood. A collection of contributions to a recent interdisciplinary CECAM (Center Européen de Calcul Atomique et Moléculaire) workshop is used here to provide an overview of the progress and remaining limitations in the understanding of the mechanistic foundations of allostery gained from computational and experimental analyses of real protein systems and model systems. The main conceptual frameworks instrumental in driving the field are discussed. We illustrate the role of these frameworks in illuminating molecular mechanisms and explaining cellular processes, and describe some of their promising practical applications in engineering molecular sensors and informing drug design efforts.
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Sitio Alostérico , Técnicas Biosensibles , Diseño de Fármacos , Proteínas/química , Regulación Alostérica , Animales , Regulación de la Expresión Génica , Humanos , Redes y Vías Metabólicas , Simulación de Dinámica Molecular , Proteínas/genética , Proteínas/metabolismo , Transducción de Señal , Termodinámica , Transcripción GenéticaRESUMEN
RESUMO Em 23 de setembro de 1999, foi aprovada a criação do subsistema de saúde indígena no âmbito do Sistema Único de Saúde. Neste trabalho, analisamos as bases discursivas de convergência e conflitos entre discursos indigenistas e da Reforma Sanitária, que nos permitem refletir sobre esse processo que consideramos configurar uma 'longa' Reforma Sanitária indígena. Utilizamos como referencial teórico a perspectiva da teoria de Stephen Ball, para analisar documentos produzidos por atores indigenistas (Fundação Nacional do Índio - Funai, Conselho Indigenista Missionário - Cimi e União das Nações Indígenas - UNI) e pelo Movimento da Reforma Sanitária. Apontamos evidências da utilização por indígenas e indigenistas dos argumentos e das propostas da Reforma Sanitária, e, por outro lado, o envolvimento estratégico de Sergio Arouca nos debates da saúde indígena. Os pontos de convergência se localizam principalmente na crítica ao modelo biomédico, à aproximação das propostas da atenção primária e do conceito ampliado de saúde. Os conflitos se relacionaram principalmente quanto à operacionalização do subsistema, mas o discurso indigenista, contrário à municipalização, encontrou na distritalização uma proposta legitimada na Reforma Sanitária.
ABSTRACT On September 23, 1999, the indigenous health subsystem was created within the scope of the Unified Health System. In this work, we analyze the discursive bases of convergence and conflicts between indigenist discourses and the health reform, which allow us to reflect on this process which we consider a 'long' indigenous health reform. We used as reference the perspective of Stephen Ball's theory, to analyze documents produced by indigenist actors (National Indian Foundation - Funai, Indian Missionary Council - Cimi and Union of Indigenous Nations - UNI) and the Health Reform Movement. We point to evidence of indigenous and indigenist use of arguments and proposals for sanitary reform and, on the other hand, the strategic involvement of Sergio Arouca in indigenous health events. The points of convergence are located mainly in the critique of the biomedical model, the approximation of primary care proposals, and the concept of health. Conflicts were mainly related to the operationalization of the subsystem, but the indigenist discourse, contrary to municipalization, found in the district process a proposal legitimized in the Health Reform.
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Amorphous packings of nonspherical particles such as ellipsoids and spherocylinders are known to be hypostatic: The number of mechanical contacts between particles is smaller than the number of degrees of freedom, thus violating Maxwell's mechanical stability criterion. In this work, we propose a general theory of hypostatic amorphous packings and the associated jamming transition. First, we show that many systems fall into a same universality class. As an example, we explicitly map ellipsoids into a system of "breathing" particles. We show by using a marginal stability argument that in both cases jammed packings are hypostatic and that the critical exponents related to the contact number and the vibrational density of states are the same. Furthermore, we introduce a generalized perceptron model which can be solved analytically by the replica method. The analytical solution predicts critical exponents in the same hypostatic jamming universality class. Our analysis further reveals that the force and gap distributions of hypostatic jamming do not show power-law behavior, in marked contrast to the isostatic jamming of spherical particles. Finally, we confirm our theoretical predictions by numerical simulations.