Quantum phase transitions of atom-molecule Bose mixtures in a double-well potential

The ground state and spectral properties of Bose gases in double-well potentials are studied in two different scenarios: i) an interacting atomic Bose gas, and ii) a mixture of an atomic gas interacting with diatomic molecules. A ground state second-order quantum phase transition (QPT) is observed in both scenarios. For large attractive values of the atom-atom interaction, the ground-state is degenerate. For repulsive and small attractive interaction, the ground-state is not degenerate and is well approximated by a boson coherent state. Both systems depict an excited state quantum phase transition (ESQPT). For the mixed atom-molecule system the critical point of the ESQPT displays a discontinuity in the first derivative of the density of states.Comment: 25 pages, 18 figures. RevTex 4.1 (version to appear in Phys. Rev. E

Regulation of Ribosomal RNA Production by RNA Polymerase I: Does Elongation Come First?

Ribosomal RNA (rRNA) production represents the most active transcription in the cell. Synthesis of the large rRNA precursors (35–47S) can be achieved by up to 150 RNA polymerase I (Pol I) enzymes simultaneously transcribing each rRNA gene. In this paper, we present recent advances made in understanding the regulatory mechanisms that control elongation. Built-in Pol I elongation factors, such as Rpa34/Rpa49 in budding yeast and PAF53/CAST in humans, are instrumental to the extremely high rate of rRNA production per gene. rRNA elongation mechanisms are intrinsically linked to chromatin structure and to the higher-order organization of the rRNA genes (rDNA). Factors such as Hmo1 in yeast and UBF1 in humans are key players in rDNA chromatin structure in vivo. Finally, elongation factors known to regulate messengers RNA production by RNA polymerase II are also involved in rRNA production and work cooperatively with Rpa49 in vivo

Exploración posturográfica de pacientes simuladores

Introduction: An aphysiological pattern in computerized dynamic posturography (CDP) may be produced by numerous causes. We analyze the results obtained in this test by a group of malingering patients. Patients and method: This study analyzes a particular group of 7 malingerers, ie patients simulating a false and unreal equilibrium disorder, without any a priori awareness of the gain expected from a pathological report. The condition can only be identified with the very complex postural disorder known as “continuous imbalance.” We analyze the results of the dynamic posturography test following the diagnostic criteria described by other authors. Results: Of the criteria analyzed, we found Cevette’s to be the most frequently positive for our study group. Conclusions: The wide diversity in the criteria used makes it necessary to apply them together, assuming a high level of suspicion and great care in the diagnostic process

Mutations in TFIIH causing trichothiodystrophy are responsible for defects in ribosomal RNA production and processing

The basal transcription/repair factor II H (TFIIH), found mutated in cancer-prone or premature aging diseases, plays a still unclear role in RNA polymerase I transcription. Furthermore, the impact of this function on TFIIHrelated diseases, such as trichothiodystrophy (TTD), remains to be explored. Here, we studied the involvement of TFIIH during the whole process of ribosome biogenesis, from RNAP1 transcription to maturation steps of the ribosomal RNAs. Our results show that TFIIH is recruited to the ribosomal DNA in an active transcription- dependent manner and functions in RNAP1 transcription elongation through ATP hydrolysis of the XPB subunit. Remarkably, we found a TFIIH allele-specific effect, affecting RNAP1 transcription and/or the pre-rRNA maturation process. Interestingly, this effect was observed in mutant TFIIH-TTD cells and also in the brains of TFIIH-TTD mice. Our findings provide evidence that defective ribosome synthesis represents a new faulty mechanism involved in the pathophysiology of TFIIH-related diseases.</p

Mutations in TFIIH causing trichothiodystrophy are responsible for defects in ribosomal RNA production and processing

The basal transcription/repair factor II H (TFIIH), found mutated in cancer-prone or premature aging diseases, plays a still unclear role in RNA polymerase I transcription. Furthermore, the impact of this function on TFIIHrelated diseases, such as trichothiodystrophy (TTD), remains to be explored. Here, we studied the involvement of TFIIH during the whole process of ribosome biogenesis, from RNAP1 transcription to maturation steps of the ribosomal RNAs. Our results show that TFIIH is recruited to the ribosomal DNA in an active transcription- dependent manner and functions in RNAP1 transcription elongation through ATP hydrolysis of the XPB subunit. Remarkably, we found a TFIIH allele-specific effect, affecting RNAP1 transcription and/or the pre-rRNA maturation process. Interestingly, this effect was observed in mutant TFIIH-TTD cells and also in the brains of TFIIH-TTD mice. Our findings provide evidence that defective ribosome synthesis represents a new faulty mechanism involved in the pathophysiology of TFIIH-related diseases.</p

Relationships between physical activity frequency and self-perceived health, self-reported depression, and depressive symptoms in spanish older adults with diabetes: a cross-sectional study

Diabetes is one of the most prevalent noncommunicable diseases in the world. This disease can affect both physical and mental health in the population. This study analyzed the prevalence of Self-Perceived Health (SPH), self-reported depression, and depressive symptoms in comparison with the Physical Activity Frequency (PAF) reported by Spanish older adults with diabetes. A cross-sectional study was carried out with data from 2799 self-reported diabetic participants, all of whom were residents of Spain, aged 50–79 years, and included in the European Health Surveys carried out in Spain (EHIS) both in 2014 and 2020. The relationships between the variables were analysed with a chi-squared test. A z-test for independent proportions was performed to analyze differences in proportions between the sexes. A multiple binary logistic regression was carried out on the prevalence of depression. Linear regressions were performed on depressive symptoms and SPH. Dependent relationships were found between the SPH, self-reported depression, and depressive symptoms with PAF. Most of the very active participants reported a higher prevalence of self-reported depression. Physical inactivity increased the risk of depression, major depressive symptoms, and negative SPH.info:eu-repo/semantics/publishedVersio

Cooperative Learning vs. Projecto Based Learning a practical case

The Bologna Declaration and the implementation of the European Higher Education Area are promoting the use of active learning methodologies such as cooperative learning and project based learning. This study was motivated by the comparison of the results obtained after applying Cooperative Learning (CL) and Project Based Learning (PBL) to a subject of Computer Engineering. The fundamental hypothesis tested was whether the academic success achieved by the students of the first years was higher when CL was applied than in those cases to which PBL was applied. A practical case, by means of which the effectiveness of CL and PBL are compared, is presented in this work. This study has been carried out at the Universidad Politécnica de Madrid, where these mechanisms have been applied to the Operating Systems I subject from the Technical Engineering in Computer Systems degree (OSIS) and to the same subject from the Technical Engineering in Computer Management degree (OSIM). Both subjects have the same syllabus, are taught in the same year and semester and share also formative objectives. From this study we can conclude that students' academic performance (regarding the grades given) is greater with PBL than with CL. To be more specific, the difference is between 0.5 and 1 point for the individual tests. For the group tests, this difference is between 2.5 and 3 points. Therefore, this study refutes the fundamental hypothesis formulated at the beginning. Some of the possible interpretations of these results are referred to in this stud

Pol5 is required for recycling of small subunit biogenesis factors and for formation of the peptide exit tunnel of the large ribosomal subunit

More than 200 assembly factors (AFs) are required for the production of ribosomes in yeast. The step-wise association and dissociation of these AFs with the pre-ribosomal subunits occurs in a hierarchical manner to ensure correct maturation of the prerRNAs and assembly of the ribosomal proteins. Although decades of research have provided a wealth of insights into the functions of many AFs, others remain poorly characterized. Pol5 was initially classified with B-type DNA polymerases, however, several lines of evidence indicate the involvement of this protein in ribosome assembly. Here, we show that depletion of Pol5 affects the processing of pre-rRNAs destined for the both the large and small subunits. Furthermore, we identify binding sites for Pol5 in the 5' external transcribed spacer and within domain III of the 25S rRNA sequence. Consistent with this, we reveal that Pol5 is required for recruitment of ribosomal proteins that form the polypeptide exit tunnel in the LSU and that depletion of Pol5 impairs the release of 5' ETS fragments from early pre-40S particles. The dual functions of Pol5 in 60S assembly and recycling of pre-40S AFs suggest that this factor could contribute to ensuring the stoichiometric production of ribosomal subunits

“Liderazgo Transformacional y Clima Laboral en Empresa de Actividades Tecnológicas”

El objetivo de este estudio es analizar el liderazgo Transformacional en una empresa de actividades tecnológicas y su impacto en el clima laboral. Este trabajo de investigación comprende tres objetivos específicos. En el primero, es definir la relación entre el liderazgo transformacional y el clima laboral. En el segundo, se busca hacer un diagnóstico del liderazgo y el clima laboral en la empresa. El último objetivo específico, es proponer recomendaciones y soluciones para potenciar el liderazgo y el clima laboral y sus implicancias de decisión de dicha organización. La metodología utilizada en este trabajo es de tipo cualitativo, porque trata de un estudio de caso en base a experiencias. Para su desarrollo, se recogió información a través de entrevistas de los trabajadores de la misma empresa. El principal hallazgo es que parte importante de un buen clima laboral es que el líder considere y explote las habilidades de cada miembro del equipo y los hagan sentir importantes, de esa manera aflore lo mejor de cada trabajador. La conclusión principal, es que la ausencia del liderazgo transformacional es un problema para el éxito empresarial, ya que influye de manera negativa en los procesos de sus actividades laborales, debido a la inestabilidad emocional de sus colaboradores. Motivo por el cual, el potencial del mismo personal se vería opacado y estancaría el logro de las metas compartidas con la empresa.The objective of this study is to analyze Transformational leadership in a technological activities company and its impact on the work environment. This research work includes three specific objectives. The first is to define the relationship between transformational leadership and the work environment. In the second, we seek to make a diagnosis of the leadership and work environment in the company. The last specific objective is to propose recommendations and solutions to enhance the leadership and work environment and its decision implications for said organization. The methodology used in this work is qualitative, because it is a case study based on experiences. For its development, information was collected through interviews with workers from the same company. The main finding is that an important part of a good work environment is that the leader considers and exploits the abilities of each team member and makes them feel important, thus bringing out the best in each worker. The main conclusion is that the absence of transformational leadership is a problem for business success, since it negatively influences the processes of its work activities, due to the emotional instability of its collaborators. For this reason, the potential of the same personnel would be overshadowed and the achievement of the goals shared with the company would stagnate.Trabajo de Suficiencia Profesiona

Evaluation of a Planar Reconfigurable Phased Array Antenna Driven by a Multi-Channel Beamforming Module at Ka Band

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksIn this paper, a planar active phased array antenna demonstration with linear polarization (LP) at Ka Band (28-30 GHz) is presented. The proof of concept is carried out to evaluate the possible problems that may arise, to analyze possible calibration stages and to assess the viability of the integration of an active system with a Multi-Channel Beamforming Module (MCBM). To fulfill this task an 8times 8-element planar array arranged in column subarrays of 1times 8 elements for 1D beam steering is proposed. The single element consists of a printed circular patch connected to a microstrip feeding line through metallic vias in a multilayered structure. Both the amplitude and phase distributions are performed by a commercial integrated circuit (IC) designed for transmission purposes, from the common port to each of the 8 output ports. Thus, an evaluation of the IC performance is also included within this work. Despite the inherent amplitude and phase feeding errors of the IC, the beam-steering accuracy of the system is reasonable. A nice correspondence between the simulated and measured 8times 8-element array beam steering directions is obtained, with errors below 1° in the steering of the beamThis work was supported in part by the Spanish Government, Ministry of Economy, National Program of Research, Development and Innovation through the Project FUTURE RADIO ’’Radio systems and technologies for high capacity terrestrial and satellite communications in an hyperconnected world’’ under Grant TEC2017-85529-C3-1-R, and in part by the Project JETSTREAM ’’Desarrollo de una antena banda KA embarcada para la prestación de servicios de acceso a Internet por satélite en aviación comercial’’ in collaboration with TELNET Redes Inteligentes S.A. under Grant RTC-2015-3495-