Simulation of the phonon-limited electron mobility in multi-layer MoS 2 field-effect transistors

We study the electron mobility in Metal-Insulator-Semiconductor Field-Effect-Transistors which use multi-layer MoS 2 as channel. The electrostatic behavior is calculated by self-consistently solving the 1D Poisson and Schrödinger equations under the effective mass approximation. Phonon-limited electron mobility is then calculated solving the Boltzmann Transport Equation under the Momentum Relaxation Time approximation for different device sizes and bias conditions

GFET Asymmetric Transfer Response Analysis through Access Region Resistances

Graphene-based devices are planned to augment the functionality of Si and III-V based technology in radio-frequency (RF) electronics. The expectations in designing graphene field-effect transistors (GFETs) with enhanced RF performance have attracted significant experimental efforts, mainly concentrated on achieving high mobility samples. However, little attention has been paid, so far, to the role of the access regions in these devices. Here, we analyse in detail, via numerical simulations, how the GFET transfer response is severely impacted by these regions, showing that they play a significant role in the asymmetric saturated behaviour commonly observed in GFETs. We also investigate how the modulation of the access region conductivity (i.e., by the influence of a back gate) and the presence of imperfections in the graphene layer (e.g., charge puddles) affects the transfer response. The analysis is extended to assess the application of GFETs for RF applications, by evaluating their cut-off frequency.This research was founded by Spanish government grant numbers TEC2017-89955-P (MINECO/AEI/FEDER, UE), TEC2015-67462-C2-1-R (MINECO), IJCI-2017-32297 (MINECO/AEI), FPU16/04043 and FPU14/02579, and the European Union’s Horizon 2020 Research and Innovation Program under Grant GrapheneCore2 785219

Effectiveness of an Eye-Cervical Re-Education Program in Chronic Neck Pain: A Randomized Clinical Trial

Objectives. Proprioceptive training is popularly applied as a therapeutic exercise method in physiotherapy. Its effects on pain and range of motion are only poorly evaluated. Therefore, this study assesses the effectiveness of proprioceptive training with an Eye-Cervical Re-education Program to decrease pain and increase the joint range in chronic neck pain patients. Material and Methods. Design. A randomized, no-blinded, controlled clinical trial. Setting. Physiotherapy consultation. Participants. 44 people were divided into two groups. Interventions. All patients were treated with a multimodal physiotherapy intervention. The experimental group was supplemented with an exercise program that included eye-cervical proprioception. Outcomes. The primary outcomes included pain pressure thresholds (upper trapezius, levator scapulae, and splenius capitis) and cervical range of motion. The secondary outcomes included pain measured by the Visual Analogical Scale and the McGillSpv Questionnaire. Results. The proprioception treatment was effective in reducing the pain pressure threshold in the right upper trapezius (p=0.001), left upper trapezius (p=0.014), right levator scapula (p=0.040), and left splenius capitis (p=0.021). The increase in the joint range was statistically significant (p<0.05) in favor of the Eye-Cervical Re-education Program for all movements assessed. Conclusions. The Eye-Cervical Re-education Program is effective at relieving pain pressure thresholds in the upper trapezius, right levator scapula, and left splenius capitis and especially effective for increasing the cervical range of motion. This trial is registered with (retrospective registration)

Continuous Positive Airway Pressure Treatment in Patients with Alzheimer's Disease: A Systematic Review

Background: Epidemiological studies have suggested a pathophysiological relationship between obstructive sleep apnea syndrome (OSAS) and Alzheimer's disease (AD). The aim of this study is to evaluate the treatment of obstructive sleep apnea with continuous positive airway pressure (CPAP) in AD and its relationship with neurocognitive function improvement. Methods: Systematic review conducted following PRISMA's statements. Relevant studies were searched in MEDLINE, PEDro, SCOPUS, PsycINFO, Web of Science, CINAHL and SportDicus. Original studies in which CPAP treatment was developel in AD patients have been included. Results: 5 studies, 3 RCTs (Randomized controlled trials) and 2 pilot studies. In all RCTs the CPAP intervention was six weeks; 3 weeks of therapeutic CPAP vs. 3 weeks placebo CPAP (pCPAP) followed by 3 weeks tCPAP in patients with AD and OSA. The two pilot studies conducted a follow-up in which the impact on cognitive impairment was measured. Conclusions: CPAP treatment in AD patients decreases excessive daytime sleepiness and improves sleep quality. There are indications that cognitive deterioration function measured with the Mini Mental Scale decreases or evolves to a lesser extent in Alzheimer's patients treated with CPAP. Caregivers observe stabilization in disease progression with integration of CPAP. More research is needed on the topic presented

Hole mobility of cylindrical GaSb nanowires

The hole mobility of GaSb field-effect transistor nanowires is analyzed as a function of the device orientation and gate bias. To this purpose, a self-consistent Poisson-Schrödinger solver with an 88 k·p Hamiltonian is employed to study the electrostatics, and the hole mobility is calculated under the momentum relaxation time solution of the Boltzmann transport equation including the main high-field scattering mechanisms.The authors acknowledge the support by the Spanish Government under the Project TEC2014-59730-R

Biotinylated Cell-penetrating Peptides to Study Intracellular Protein-protein Interactions

[EN] Here we present a protocol to study intracellular protein-protein interactions that is based on the widely used biotin-avidin pull-down system. The modification presented includes the combination of this technique with cell-penetrating sequences. We propose to design cell-penetrating baits that can be incubated with living cells instead of cell lysates and therefore the interactions found will reflect those that occur within the intracellular context. Connexin43 (Cx43), a protein that forms gap junction channels and hemichannels is down-regulated in high-grade gliomas. The Cx43 region comprising amino acids 266-283 is responsible for the inhibition of the oncogenic activity of c-Src in glioma cells. Here we use TAT as the cell-penetrating sequence, biotin as the pull-down tag and the region of Cx43 comprised between amino acids 266-283 as the target to find intracellular interactions in the hard-to-transfect human glioma stem cells. One of the limitations of the proposed method is that the molecule used as bait could fail to fold properly and, consequently, the interactions found could not be associated with the effect. However, this method can be especially interesting for the interactions involved in signal transduction pathways because they are usually carried out by intrinsically disordered regions and, therefore, they do not require an ordered folding. In addition, one of the advantages of the proposed method is that the relevance of each residue on the interaction can be easily studied. This is a modular system; therefore, other cell-penetrating sequences, other tags, and other intracellular targets can be employed. Finally, the scope of this protocol is far beyond protein-protein interaction because this system can be applied to other bioactive cargoes such as RNA sequences, nanoparticles, viruses or any molecule that can be transduced with cell-penetrating sequences and fused to pull-down tags to study their intracellular mechanism of action

Numerical study of p-type InSb and GaSb nanowires

III-V nanowires (NWs) have attracted extensive research interests in recent years because of their unique physical properties, being recognized as promising building blocks for the next generation of electronics and photonics. Most of the works up-to-date are, however, focused on n-type devices where materials such as InAs or InGaAs have already demonstrated impressive performance. Nevertheless, for the practical implementation of CMOS circuits based on NWs, p- channel FETs are mandatory. Several materials are currently being investigated as technologically relevant p-type semiconductors. In particular, increasingly more attention has been focused on InSb and GaSb NWs owing to their excellent hole transport properties. In this work we study the electrostatic properties of traditional p-type NWs based on Si and Ge compared to III-V materials.This work was supported by the Spanish Government under the Project TEC2014-59730-R. C. Martínez-Blanque acknowledges the Junta de Andalucía support under project P09-TIC4873. A. Toral also acknowledges the University of Granada funding through the Becas de Iniciación a la Investigación para alumnus de Máster. J. M. González-Medina also acknowledges grant FPU014/02579

Gate capacitance performance of p-type InSb and GaSb nanowires

The electrostatic behavior of p-type nanowires made of antimonide III-V materials (InSb and GaSb) is analyzed by means of a self-consistent solution of the Poisson and Schrödinger equations, under the k·p approximation. The results are compared to those achieved for Si and Ge NWs, and the contribution of each of the capacitance terms (quantum and inversion layer capacitances) is thoroughly analyzed.This work was supported by the Spanish Government under the Project TEC2014-59730-R. C. Martínez-Blanque acknowledges the Junta de Andalucía support under project P09-TIC4873

A Short Region of Connexin43 Reduces Human Glioma Stem Cell Migration, Invasion, and Survival through Src, PTEN, and FAK

[EN] Connexin43 (CX43), a protein that forms gap junction channels and hemichannels in astrocytes, is downregulated in high-grade gliomas. Its relevance for glioma therapy has been thoroughly explored; however, its positive effects on proliferation are counterbalanced by its effects onmigration and invasion. Here,weshowthat a cell-penetrating peptide based onCX43(TAT-Cx43266-283) inhibited c-Src and focal adhesion kinase (FAK) and upregulated phosphatase and tensinhomolog inglioma stem cells (GSCs) derived from patients. Consequently, TAT-Cx43266-283 reduced GSC motility, as analyzed by time-lapse microscopy, and strongly reduced their invasive ability. Interestingly, we investigated the effects of TAT-Cx43266-283 on freshly removed surgical specimens as undissociated glioblastoma blocks, which revealed a dramatic reduction in the growth, migration, and survival of these cells. In conclusion, a region of CX43 (amino acids 266–283) exerts an important anti-tumor effect in patient-derived glioblastoma models that includes impairment of GSC migration and invasion