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Introduction: Adequate health literacy enables patients and caregivers to make appropriate decisions and achieve better health outcomes. However, much information about health literacy comes from developed and English-speaking countries. There is very little information about health literacy levels in countries such as Colombia and these data, therefore, cannot be used as an input in the development of cardiovascular education programs for the community. Our objective was to optimize and adapt the Spanish validation of the short version of the Test of Functional Health Literacy in adults (s-TOFHLA) to the context of the Colombian health system. This test was chosen because its multiple questions and sections can guide the skills that should be emphasized in a health education course for patients and caregivers (i.e. navigation in the health care system, interpretation of medical instructions, understanding of doses and forms of drug dispensing). This test consists of two parts: numerical and reading comprehension (Readings A and B). The TOFHLA is graded using a score between 1 and 100 points, which classifies the participant into categories of adequate, marginal or inadequate health literacy. Methods: The validation process was carried out in the following steps 1) cultural and language adaptation, 2) expert consensus (n=7), 3) a cognitive survey (n=10), 4) piloting (n=40), and 5) application in the community (n=148). The study was conducted in 6 cities, from 5 departments (equivalent to an state) in Colombia. Results: In the piloting (n=40) Cronbach's α was 0.76 for numerical comprehension, 0.58 for reading A, and 0.95 for reading B. In the broader sample (n=148) the Cronbach's α for numerical comprehension, reading A and reading B was 0.84, 0.89, and 0.95, respectively. Most of the sample had an adequate level of literacy (77.1%), however, the percentages in the marginal (6%) and inadequate (16.7%) categories can still be considered high. Health literacy levels are lower in people with the lowest level of schooling and socioeconomic strata. In addition, there seem to be differences between urban and rural populations. No differences have been observed according to the sex of the participants. Conclusions: It is critical to assess health literacy with instruments that have been adequately validated and adapted to the conditions of each health system. This process requires the participation of health and language experts. The piloting and cognitive surveys provide a good idea of how communities interpret psychometric tests. Our results confirm differences in health literacy among populations with different levels of income and schooling. Health literacy assessment can guide the instructional design of community-directed health education programs.

Chaotic systems are hard to synchronize, and no general solution exists. The presence of hidden attractors makes finding a solution particularly elusive. Successful synchronization critically depends on the control strategy, which must be carefully chosen considering system features such as the presence of hidden attractors. We studied the feasibility of fuzzy control for synchronizing chaotic systems with hidden attractors and employed a special numerical integration method that takes advantage of the oscillatory characteristic of chaotic systems. We hypothesized that fuzzy synchronization and the chosen numerical integration method can successfully deal with this case of synchronization. We tested two synchronization schemes: complete synchronization, which leverages linearization, and projective synchronization, capitalizing on parallel distributed compensation (PDC). We applied the proposal to a set of known chaotic systems of integer order with hidden attractors. Our results indicated that fuzzy control strategies combined with the special numerical integration method are effective tools to synchronize chaotic systems with hidden attractors. In addition, for projective synchronization, we propose a new strategy to optimize error convergence. Furthermore, we tested and compared different Takagi–Sugeno (T–S) fuzzy models obtained by tensor product (TP) model transformation. We found an effect of the fuzzy model of the chaotic system on the synchronization performance.

The increasing incidence of physiologic/pathologic conditions that impair the otherwise routine healing of endochondral bone fractures and the occurrence of severe bone injuries necessitate novel approaches to enhance clinically challenging bone fracture repair. To promote the healing of nonunion fractures, we tested an approach that used two small molecules to sequentially enhance cartilage development and conversion to bone in the callus of a murine femoral segmental defect nonunion model of bone injury. Systemic injections of SAG21k were used to stimulate chondrogenesis through the activation of the hedgehog (SHH) pathway early in bone repair, while injections of the prolyl hydroxylase domain (PHD)2 inhibitor, IOX2, were used to stimulate hypoxia signaling-mediated endochondral bone formation. The expression of SHH pathway genes and Phd2 target genes was increased in chondrocyte cell lines in response to SAG21k and IOX2 treatment, respectively. The segmental defect responded to sequential systemic administration of these small molecules with increased chondrocyte expression of PTCH1, GLI1, and SOX9 in response to SAG and increased expression of HIF-1α and VEGFA in the defect tissues in response to IOX2. At six weeks post-surgery, the combined SAG-IOX2 therapy produced increased bone formation in the defect with bony union over the injury. This article is protected by copyright. All rights reserved.

Articular distal radius fractures (DRFs) have increased in incidence in recent years, especially among the economically active population. Most of the treatment approaches are based on plain X- rays, and do not give us any information on how to treat these fractures. In the search for solutions with greater precision in diagnosis, in reducing the joint surface of the fracture, and envolving minimally-invasive techniques, we found arthroscopy as the main tool for these patients. Therefore, an enhanced understanding of the biomechanics of the different types of fracture associated with ligamentous lesions should facilitate the right decision regarding the treatment. The present paper aims at providing a management-oriented concept to diagnose and treat ligamentous lesions associated with intra-articular DRFs based on a arthroscopy-assisted procedure, and showing the objective and patient-reported outcomes and a new classification. The objective and patient-reported outcomes were: the mean range of motion (ROM) was of 94.80% on the non-affected side; the mean score on the abbreviated version of the Disabilities of the Arm, Shoulder and Hand questionnaire (QuickDASH) was of 3.6 (range: 1 to 12). The score on the Visual Analog Scale (VAS) was of 1.66 (range: 1 to 3). Complications were observed in 2 (13.33%) patients: extensor tendon synovitis in 1 patient, and a limitation (stiffness) in ROM in 1 patient, both treated with wrist arthroscopy release. The mean time until the return to work was of 6.4 weeks. In patients with unstable intra-articular DRFs associated with ligamentous lesions, the fixation of specific osseous-ligamentous fragments and ligamentous repair/reconstruction by wrist arthroscopy prove to be a safe and reliable treatment. The clinical and functional results predict that the patients can return to work more quickly.

Gliosarcoma, a variant of glioblastoma, is a rare and aggressive tumor of the central nervous system (CNS) composed of glial and sarcomatous tissues. Up to now, there are only 2 reported cases of gliosarcoma of the optical pathway. We report a case from March 2018 of a 53-year-old male patient presented with 6 months’ of right fronto-orbital pulsatile headache, behavior changes, and visual loss. The MRI study showed an expansile optic pathway lesion involving the chiasm and right optic nerve. The diagnosis of gliosarcoma was obtained by open brain biopsy and immunohistochemical analysis. Although gliosarcoma is rare, it should be considered a differential diagnosis even in optic pathway tumors in older patients. The experience of the neuropathologist with a trained eye can be the differential in the accurate diagnostic process. Optic pathway, Gliosarcoma, Glioblastoma, Magnetic resonance imaging

Spinal dysraphisms (SDs) are congenital malformations of the spinal cord, determined by derangement in the complex cascade of embryologic events involved in spinal development. They represent a heterogeneous group ranging from mild clinical manifestations-going unnoticed or being discovered at clinical examination-to a causal factor of life quality impairment, especially when associated with musculoskeletal, gastrointestinal, genitourinary, or respiratory system malformations. Knowledge of the normal embryologic development of the spinal cord-which encompasses three main steps (gastrulation, primary neurulation, and secondary neurulation)-is crucial for understanding the pathogenesis, neuroradiologic scenarios, and clinical-radiologic classification of congenital malformations of the spinal cord. SDs can be divided with clinical examination or neuroradiologic study into two major groups: open SDs and closed SDs. Congenital malformations of the spinal cord include a wide range of abnormalities that vary considerably in imaging and clinical characteristics and complexity and therefore may represent a diagnostic challenge, even for the experienced radiologist.

Pathological obesity and its complications are associated with an increased propensity for bone fractures. Humans with certain genetic polymorphisms at the kinase suppressor of ras2 (Ksr2) locus develop severe early-onset obesity and type 2 diabetes (T2D). Both conditions are phenocopied in mice with Ksr2 deleted, but whether this affects bone health remains unknown. Here we studied the bones of global Ksr2 null mice and found that Ksr2 negatively regulates femoral, but not vertebral, bone mass in two genetic backgrounds, while the paralogous gene, Ksr1, was dispensable for bone homeostasis. Mechanistically, KSR2 regulates bone formation by influencing adipocyte differentiation at the expense of osteoblasts in the bone marrow. Compared with Ksr2’s known role as a regulator of feeding by its function in the hypothalamus, pair feeding and osteoblast-specific conditional deletion of Ksr2 reveals that Ksr2 can regulate bone formation autonomously. Despite the gains in appendicular bone mass observed in absence of Ksr2, bone strength, as well as fracture healing response remains compromised in these mice. This study highlights the interrelationship between adiposity and bone health and provides mechanistic insights into how Ksr2, an adiposity and diabetic gene, regulates bone metabolism.

Pathological obesity and its complications are associated with an increased propensity for bone fractures. Humans with certain genetic polymorphisms at the kinase suppressor of ras2 (KSR2) locus develop severe early-onset obesity and type 2 diabetes. Both conditions are phenocopied in mice withOur bones are living tissues which constantly reshape and renew themselves. This ability relies on stem cells present in the marrow cavity, which can mature into the various types of cells needed to produce new bone material, marrow fat, or other components. Obesity and associated conditions such as type 2 diabetes are often linked to harmful changes in the skeleton. In particular, these metabolic conditions are associated with weight-bearing bones becoming more prone to facture and healing poorly. Mice genetically modified to model obesity and diabetes could help researchers to study exactly how these conditions – and the genetic changes that underlie them – impact bone health. Gomez et al. aimed to address this question by focusing on

Many efforts have been made to create scenarios whereby interconnecting IoT can be used. The primary objective of these efforts has been to centralize its access as a single list and to monitor its use and trigger its different functionalities from apps. However, few efforts have addressed the problem of electricity consumption from those devices in the context of a residence. Existing datasets for machine predictive systems are focused on data analytics for global consumption but neglect the use of such solutions by the common citizen as a means of re-educating our citizens and optimizing electricity consumption. Without considering the environmental impact and the urgent need to address this growing global emergency, ordinary citizens require systems that help them be aware of what they consume and thus aspire to make a change. In this work, we propose a methodology that builds on the formal mathematical modeling and development of a simulator to substitute the need to collect real data from real world context of use, as well as an interactive system that integrates the whole process. By adding this module to the architecture our prior work, this work is ready for use in real-life scenarios where electrical consumption could be significantly reduced, National Council of Science and Technology, CONACYT Mexico, National Scholarships for studies of Postgraduate in High Quality Institutions

The proximal and distal femur epiphysis of mice are both weight bearing structures derived from chondrocytes but differ in development. Mineralization at the distal epiphysis occurs in an osteoblast rich secondary ossification center (SOC), while the chondrocytes of the proximal femur head (FH) in particular, are directly mineralized. Thyroid hormone (TH) plays important roles in distal knee SOC formation, but whether TH also affects proximal FH development remains unexplored. Here, we found that TH controls chondrocyte maturation and mineralization at the FH in vivo through studies in Thyroid stimulating hormone receptor (Tshr-/-) hypothyroid mice by X-ray, histology, transcriptional profiling, and immunofluorescence staining. Both in vivo, and in vitro studies conducted in ATDC5 chondrocyte progenitors concur that TH regulates expression of genes that modulate mineralization (Bsp, Ocn, Dmp1, Opn, and Alp). Our work also delineates differences in prominent transcription factor regulation of genes involved in the different mechanisms leading to proximal FH cartilage calcification and endochondral ossification at the distal femur. The information on the molecular pathways contributing to postnatal cartilage calcification can provide insights on therapeutic strategies to treat pathological calcification that occurs in soft tissues such as aorta, kidney, and articular cartilage.

En el presente trabajo se da una breve explicación de la técnica de optimización por cúmulo de partículas para ser implementada como parte de la búsqueda del estado óptimo de consumo de un conjunto de dispositivos. Los dispositivos de uso doméstico, en conjunto, permiten caracterizar el consumo eléctrico de una casa habitación a través del comportamiento de uso. Cada uno de los dispositivos presenta un comportamiento de consumo. El objetivo de la optimización se refleja en la función objetivo, la cual es definida de acuerdo con el propósito general de implementación. Los datos de consumo de los dispositivos eléctricos son almacenados en vectores de consumo-hora, donde cada una de las posiciones corresponde al consumo generado por un dispositivo en una hora determinada. Cada uno de los vectores es usado por la heurística como un vector de referencia durante la búsqueda para encontrar el vector que cumple con la función objetivo.

Efficient recovery and utilization of valuable components from industrial food side streams is a main driver towards a circular economy. Among different available purification techniques, adsorption can effectively recover these components. However, the conventional batch mode of operation can limit its applicability in food processes due to limited efficiency. This work compares conventional batch packed bed adsorption with semi-continuous adsorption (so-called CaptureSMB) for the recovery of sinapic acid at industrial scale, using a food grade resin AmberliteTM FPX66. A mathematical mechanistic model able to describe semi-continuous operation is successfully validated and used to identify optimum operating parameters to maximize productivity and resin capacity utilization in batch and semi-continuous operating modes. The results indicate that CaptureSMB outperforms batch operation, increasing productivity from 5.18 g/L/h to 10.3 g/L/h for a given yield (>97%). A resin capacity utilization (RU) of around 70% is observed in both operating modes when productivity is maximized. A 92% RU can be accomplished for a given yield using the CaptureSMB process at a productivity of 7.0 g/L/h, higher than for conventional batch operation. The use of semi-continuous adsorption operation in food industry contributes to more efficient processes at reduced purification costs.

This paper focuses on analyzing, at the simulation level, the effect of the M-ary Quadrature Amplitude Modulation (M-QAM) technique, for an OFDM-RoF converged network infrastructure based on the XGS-PON standard, with a 10 Gbps capacity for a point-to-point downlink and an FTTH application, with an operating wavelength of 1550 nm or 193.4 THz (overlayed OFDM-RoF/XGS-PON system). The above, with the purpose of determining the network performance, as both the order of the M-QAM modulation and the distance of the optical link are increased, considering that the performance of a radio over optical fiber system can be significantly degraded by nonlinear phenomena present in the optical link, as well as noise and distortion phenomena that affect the signal quality. In the results of the research, the increase in the order of the M-QAM modulation allows us to represent more bits per symbol, however, a higher transmission power is required. Finally, it is considered that it is possible to develop a robust OFDM-RoF converged network infrastructure for speeds in the order of 10 Gbps for the last mile services, since it uses the advantages of both wireless and optical technologies.

Summary Between 2014 and 2016, ConocoPhillips drilled five deviated wells adjacent to a multistage, stimulated horizontal producer to sample the physical characteristics of the reservoir stimulation caused by hydraulic fracturing in the Eagle Ford Formation in DeWitt County, Texas. The design, execution, and results of the pilot are described. This pilot establishes the paucity of pre-existing natural fractures in this locale and enables the determination of the spatial characteristics of the stimulation using information derived from the core, cuttings samples, borehole-image logs, tracer logs, microseismic, distributed temperature sensing (DTS)/distributed acoustic sensing (DAS), and pressure data. Results show that stimulation effectively breaks the reservoir rock and makes a complex array of hydraulic fractures that are more closely spaced near the producer. Some fractures, however, extend interwell distances of more than 1,000 ft. The pilot data indicate that abundant proppant transport appears to be limited to distances less than 75 ft from the producer, which suggests that the stimulated rock volume (SRV) might be greater than the volume of rock that can be effectively drained.

In this research project,the deformations in the longitudinal and transverse reinforcing steel of a reinforced concrete beam with 2ϕ½” were estimated.Additionally,the displacements in thecenter of thespanweremeasuredtogether with theloads, which generatedthecrackingof the beam of dimensions180 mm×240 mm×3100 mm.Displacement were performed using a linear variable displacement transducer, and strain gauges were used to measure deformations. Finally, the applied load’s measurements were obtained with a load cell Pinzuar/Model-100/20T equipment.The physical-mechanical properties of the concreteused were determined through compressive strength tests at 28 days and modulus of elasticity.For this purpose, a load-bearing frame was used to support the beam at three points for load application.The data was collected directly on the Quantum/X2 equipment and analyzed with the help of the Catman/AP software.The maximum deformations found in the bending test at three point since there inforced concrete beam we are not greater than 8483µm/mm,presenting a failure in the center of the beam due to the creep of the tensile steel for a maximum load of 3115 Kg.Finally,the physical behavior of there inforced concrete beam with applying aload allows evaluating and optimizing this kind of systems.

The following work was carried out with the goal of studying the functionality of a previously realized design of an interchangeable indenter tool for the ball burnishing process in a numerical control milling machine with several AISI 1045 specimens, to identify and corroborate changes in the final roughness obtained and the averages of the same material with the application of the process, in addition to finding improvements in the process times, to reduce the dead times that translate into lower costs, and an improvement in the surface finish.

A nested high order sliding mode controller is proposed for speed control of a brushless direct current motor using an extended park transformation. Conventional park transformation applied to non sinusoidal back electromotive force motors results in non constant values in the (d, q) reference frame, a modified park transformation is used to obtain constant variables after transformation. Sliding mode control is robust in the presence of matched parametric variations and uncertain disturbances but unmatched variations have a negative effect in the system’s performance. A nested high order sliding mode scheme is presented to improve controller robustness to unmatched perturbations. Simulations are used to show the performance of the proposed controller with load torque and resistance variations.

Simple thermoplastic materials and polymer matrix composites have been used in this work. Polyethylene terephthalate glycol (PETG) plates, a copolymer of CHDM- cyclohexane dimethanol modified polyethylene terephthalate [56], were used, which is an amorphous and therefore transparent material, which was available in plates or extruded sheets in a wide range of thicknesses. The PETG sheets are of commercial type and their production process is carried out by the company that supplied them. Also part of the study is polyamide 6.6 with 30% short glass fibre content obtained by injection moulding and compression moulding, which was supplied by the ESIS TC4, for the first Round Robin of short glass fibre composite materials.

O presente trabalho discute o desenvolvimento das experiencias sensoriais presentes em duas cafeterias de reconhecimento mundial em suas filiais situadas na Colombia. A chegada da marca Starbucks ao pais cafeeiro em 2014, criando concorrencia com a tradicional marca Juan Valdez permitiu refletir sobre as perspectivas da experiencia da marca identificando as estrategias sensoriais e de configuracao utilizadas no planejamento dos espacos onde o produto e vendido em ambas. As duas marcas analisadas se afastam de meramente servir uma xicara de cafe de qualidade, para oferecer a seus cliente uma experiencia de conforto e plenitude que consegue entrar no cotidiano do individuo e seu estilo de vida, permitindo reafirmar sua identidade por meio do consumo.

Con el objetivo de determinar la tasa y factores relacionados con peritonitis en pacientes de una unidad de diálisis peritoneal (DP) atendidos en un hospital de Lima, Perú, se realizó un estudio retrospectivo de cohorte única durante el periodo de 2014 a 2016. Se incluyó a todos los pacientes con diagnóstico de enfermedad renal crónica del programa de DP del Hospital Cayetano Heredia. Se estimó la tasa de incidencia de peritonitis y se realizó un análisis bivariado para evaluar los factores relacionados. Se incluyó un total de 73 pacientes. La tasa de incidencia de peritonitis fue de 0,60 episodios por paciente al año; el 46,7% de los cultivos fueron positivos siendo el germen aislado más común el S. aureus. Los factores relacionados con peritonitis fueron menor valor de albúmina y hematocrito. La tasa de incidencia de peritonitis y de cultivos negativos se encontraron por encima del valor sugerido internacionalmente.

In order to determine the rate and factors related to peritonitis in peritoneal dialysis (PD) patients treated at a hospital in Lima, Peru; a retrospective single-cohort study was conducted during the period 2014-2016. All patients diagnosed with chronic renal disease from the PD program at the Cayetano Heredia Hospital were included. The incidence rate of peritonitis was estimated and a bivariate analysis was performed to assess related factors. A total of 73 patients were included. The incidence rate of peritonitis was 0.60 episodes per patient per year; 46.7% of the cultures were positive and the most common isolated germ was S. aureus. Lower albumin and hematocrit values were found to be related to peritonitis. In this study, the incidence rate of peritonitis and negative cultures were found to be higher than the internationally estimated rate.Con el objetivo de determinar la tasa y factores relacionados con peritonitis en pacientes de una unidad de diálisis peritoneal (DP) atendidos en un hospital de Lima, Perú, se realizó un estudio retrospectivo de cohorte única durante el periodo de 2014 a 2016. Se incluyó a todos los pacientes con diagnóstico de enfermedad renal crónica del programa de DP del Hospital Cayetano Heredia. Se estimó la tasa de incidencia de peritonitis y se realizó un análisis bivariado para evaluar los factores relacionados. Se incluyó un total de 73 pacientes. La tasa de incidencia de peritonitis fue de 0,60 episodios por paciente al año; el 46,7% de los cultivos fueron positivos siendo el germen aislado más común el S. aureus. Los factores relacionados con peritonitis fueron menor valor de albúmina y hematocrito. La tasa de incidencia de peritonitis y de cultivos negativos se encontraron por encima del valor sugerido internacionalmente.

Summary: The neural crest is a transient embryonic tissue that gives rise to a multitude of derivatives in an axially restricted manner. An in vitro counterpart to neural crest can be derived from human pluripotent stem cells (hPSCs) and can be used to study neural crest ontogeny and neurocristopathies, and to generate cells for therapeutic purposes. In order to successfully do this, it is critical to define the specific conditions required to generate neural crest of different axial identities, as regional restriction in differentiation potential is partly cell intrinsic. WNT and FGF signaling have been implicated as inducers of posterior fate, but the exact role that these signals play in trunk neural crest formation remains unclear. Here, we present a fully defined, xeno-free system for generating trunk neural crest from hPSCs and show that FGF signaling directs cells toward different axial identities within the trunk compartment while WNT signaling is the primary determinant of trunk versus cranial identity. : In this article, Hackland and colleagues present a highly efficient system for deriving trunk neural crest from hPSCs. They show using this system that FGF signaling dictates the axial identity of cells within the trunk compartment, but that the cranial versus trunk decision is FGF independent and is instead determined by the magnitude of WNT signaling. Keywords: trunk neural crest, WNT, FGF, human pluripotent stemm cells, CDX2, OTX2, Brachyury, SOX2, axial progenitors, NMPs

The developmental biology of neural crest cells in humans remains unexplored due to technical and ethical challenges. The use of pluripotent stem cells to model human neural crest development has gained momentum. We recently introduced a rapid chemically defined approach to induce robust neural crest by WNT/ β-CATENIN activation. Here we investigate the temporal requirements of ectopic WNT activation needed to induce neural crest cells. By altering the temporal activation of canonical WNT/ β-CATENIN with a GSK3 inhibitor we find that a 2 Day pulse of WNT/β-CATENIN activation via GSK3 inhibition is optimal to generate bona fide neural crest cells, as shown by their capacity to differentiate to neural crest specific fates including peripheral neurons, glia, melanoblasts and ectomesenchymal osteocytes, chondrocytes and adipocytes. Although a 2 Day pulse can impart neural crest character when GSK3 is inhibited days after seeding, optimal results are obtained when WNT is activated from the beginning, and we find that the window of competence to induce NCs from non-neural ectodermal/placodal precursors closes by day 3 of culture. The reduced requirement for exogenous WNT activation offers an approach that is cost effective, and we show that this adherent 2-dimensional approach is efficient in a broad range of culture platforms ranging from 96-well vessels to 10 cm dishes.

This work presents a nested super-twisting second-order sliding mode speed controller for a brushless direct current motor with a high order sliding mode observer used for back electromotive force (back-EMF) estimation. Due to the trapezoidal nature of the back-EMF, a modified Park transformation is used in order to achieve proper field orientation. Such transformation requires information from the back-EMF that is not accessible. A second-order sliding mode observer is used to estimate the back electromotive forces needed in the modified transformation. Sliding mode control is known to be robust to matched uncertain disturbances and parametric variations but it is prone to unmatched perturbations that affect the performance of the system. A nested scheme is used to improve the response of the controller in presence of unmatched disturbances. Simulations performed under similar conditions to real-time experimentation show a good regulation of the rotor speed in terms of transient and steady-state responses along with a reduced torque ripple.

The WNT/β-CATENIN pathway is critical for neural crest (NC) formation. However, the effects of the magnitude of the signal remains poorly defined. Here we evaluate the consequences of WNT magnitude variation in a robust model of human NC formation. This model is based on human embryonic stem cells induced by WNT signaling through the small molecule CHIR9902. In addition to its known effect on NC formation, we find that the WNT signal modulates the anterior-posterior axial identity of NCCs in a dose dependent manner, with low WNT leading to anterior OTX+, HOX-NC, and high WNT leading to posterior OTX−, HOX+ NC. Differentiation tests of posterior NC confirm expected derivatives including posterior specific adrenal derivatives, and display partial capacity to generate anterior ectomesenchymal derivatives. Furthermore, unlike anterior NC, posterior NC transit through a TBXT+/SOX2+ neuromesodermal precursor-like intermediate. Finally, we analyze the contributions of other signaling pathways in posterior NC formation, and suggest a critical role for FGF in survival/proliferation, and a requirement of BMP for NC maturation. As expected RA and FGF are able to modulate HOX expression in the posterior NC, but surprisingly, RA supplementation prohibits anterior, but only reduces, posterior NC formation. This work reveals for the first time that the amplitude of WNT signaling can modulate the axial identity of NC cells in humans.