212 research outputs found
Torque measurement in real time during mixing and kneading of bread dough with high content of resistant maize starch and enzymes
In this work, a methodology to measure torque during dough mixing in large scale was developed and the baking performance of bread dough formulated with resistant starch (RS) and enzymes was evaluated. Dough was formulated with 12.5 g/100 g of RS and 4 mg/100 g of a mixture of enzymes, glucose-oxidase (Gox), tranglutaminase (TG) and xylanase (HE) in proportions according to a three-component mixture design of experiments. Dough was mixed in a large-scale dynamic rheometer measuring instant torque and speed in real time through a personal computer (PC) interface. Maximum torque during mixing and parameters of the dough development curves obtained from rheofermentometer were fit to mathematical models within 95 % of confidence. Gox and TG showed positive effects on the maximum height of dough, while HE showed a negative one. Also, it was found that Gox and TG in the presence of HE could be important for reducing dough weakening.Fil: Altuna, Luz. Universidade de Sao Paulo; BrasilFil: Romano, Roberto C. O.. Universidade de Sao Paulo; BrasilFil: Pileggi, Rafael G.. Universidade de Sao Paulo; BrasilFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Tadini, Carmen C.. Universidade de Sao Paulo; Brasi
Mechanisms Involved in Epileptogenesis in Alzheimer's Disease and Their Therapeutic Implications
Altres ajuts: Fondo de Investigaciones Sanitario (FIS); National Institutes of Health (1R01AG056850-01A1, R21AG056974, R01AG061566); Fundació La Marató de TV3 (20141210); Sociedad Catalana de Neurología (SCN-2020 to MCI); Fundació Catalana Síndrome de Down; Fundació Víctor Grífols i Luca; Fundación Tatiana Pérez de Guzmán el Bueno.Epilepsy and Alzheimer's disease (AD) incidence increases with age. There are recip-rocal relationships between epilepsy and AD. Epilepsy is a risk factor for AD and, in turn, AD is an independent risk factor for developing epilepsy in old age, and abnormal AD biomarkers in PET and/or CSF are frequently found in late-onset epilepsies of unknown etiology. Accordingly, epilepsy and AD share pathophysiological processes, including neuronal hyperexcitability and an early excitatory-inhibitory dysregulation, leading to dysfunction in the inhibitory GABAergic and excitatory glutamatergic systems. Moreover, both β-amyloid and tau protein aggregates, the anato-mopathological hallmarks of AD, have proepileptic effects. Finally, these aggregates have been found in the resection material of refractory temporal lobe epilepsies, suggesting that epilepsy leads to amyloid and tau aggregates. Some epileptic syndromes, such as medial temporal lobe epilepsy, share structural and functional neuroimaging findings with AD, leading to overlapping symptomatology, such as episodic memory deficits and toxic synergistic effects. In this respect, the existence of epilepti-form activity and electroclinical seizures in AD appears to accelerate the progression of cognitive decline, and the presence of cognitive decline is much more prevalent in epileptic patients than in elderly patients without epilepsy. Notwithstanding their clinical significance, the diagnosis of clinical seizures in AD is a challenge. Most are focal and manifest with an altered level of consciousness without motor symptoms, and are often interpreted as cognitive fluctuations. Finally, despite the frequent association of epilepsy and AD dementia, there is a lack of clinical trials to guide the use of antiseizure medications (ASMs). There is also a potential role for ASMs to be used as disease-modifying drugs in AD
Bactericidal Surfaces: An Emerging 21st Century Ultra-Precision Manufacturing and Materials Puzzle
Progress made by materials scientists in recent years has greatly helped the field of ultra-precision manufacturing. Ranging from healthcare to electronics components, phenomena such as twinning, dislocation nucleation, and high-pressure phase transformation have helped to exploit plasticity across a wide range of metallic and semiconductor materials. One current problem at the forefront of the healthcare sector that can benefit from these advances is that of bacterial infections in implanted prosthetic devices. The treatment of implant infections is often complicated by the growth of bacterial biofilms on implant surfaces, which form a barrier that effectively protects the infecting organisms from host immune defenses and exogenous antibiotics. Further surgery is usually required to disrupt the biofilm, or to remove the implant altogether to permit antibiotics to clear the infection, incurring considerable cost and healthcare burdens. In this review, we focus on elucidating aspects of bactericidal surfaces inspired by the biological world to inform the design of implant surface treatments that will suppress bacterial colonization. Alongside manufacturing and materials related challenges, the review identifies the most promising natural bactericidal surfaces and provides representative models of their structure, highlighting the importance of the critical slope presented by these surfaces. The scalable production of these complex hierarchical structures on freeform metallic implant surfaces has remained a scientific challenge to date and, as identified by this review, is one of the many 21st-century puzzles to be addressed by the field of applied physics
Chronological reassessment of the Middle to Upper Paleolithic transition and Early Upper Paleolithic cultures in Cantabrian Spain
Abstract: Methodological advances in dating the Middle to Upper Paleolithic transition provide a better understanding of the replacement of local Neanderthal populations by Anatomically Modern Humans. Today we know that this replacement was not a single, pan-European event, but rather it took place at different times in different regions. Thus, local conditions could have played a role. Iberia represents a significant macro-region to study this process. Northern Atlantic Spain contains evidence of both Mousterian and Early Upper Paleolithic occupations, although most of them are not properly dated, thus hindering the chances of an adequate interpretation. Here we present 46 new radiocarbon dates conducted using ultrafiltration pre-treatment method of anthropogenically manipulated bones from 13 sites in the Cantabrian region containing Mousterian, Aurignacian and Gravettian levels, of which 30 are considered relevant. These dates, alongside previously reported ones, were integrated into a Bayesian age model to reconstruct an absolute timescale for the transitional period. According to it, the Mousterian disappeared in the region by 47.9?45.1ka cal BP, while the Châtelperronian lasted between 42.6k and 41.5ka cal BP. The Mousterian and Châtelperronian did not overlap, indicating that the latter might be either intrusive or an offshoot of the Mousterian. The new chronology also suggests that the Aurignacian appears between 43.3?40.5ka cal BP overlapping with the Châtelperronian, and ended around 34.6?33.1ka cal BP, after the Gravettian had already been established in the region. This evidence indicates that Neanderthals and AMH co-existed <1,000 years, with the caveat that no diagnostic human remains have been found with the latest Mousterian, Châtelperronian or earliest Aurignacian in Cantabrian Spain.This research has been supported by the European Commission through FP7-PEOPLE-2012-CIG (Ref: 322112), the Spanish Ministry of Economy and Competitiveness (HAR2012-33956 and RYC-2011-00695), Cantabria Campus International and University of Cantabria to ABMA. The Instituto Internacional de Investigaciones Prehistóricas de Cantabria is sponsored by the University of Cantabria, the Government of Cantabria and Banco Santander
Acceleration of High Intensity Proton Beams
In 1998 the CERN SPS accelerator finished a five years long program providing 450GeV proton beams for neutrino physics. These experiments required the highest possible beam intensity the SPS can deliver. During the last five years the maximum proton intensity in the SPS has steadily been increased to a maximum of 4.8 1013 protons per cycle. In order to achieve these intensities a careful monitoring and improvement of the vertical aperture was necessary. Improved feedback systems on the different RF cavities were needed in order to avoid instabilities. Also the quality (emittance and extraction spill) of the injector, the CERN PS, had be optimised
The SPS as accelerator of Pb ions
In 1994 the CERN SPS was used for the first time to accelerate fully stripped ions of the Pb208 isotope from the equivalent proton momentum of 13 GeV/c to 400 GeV/c. In the CERN PS, which was used as injector, the lead was accelerated as Pb53+ ions and then fully stripped in the transfer line from PS to SPS. The radio frequency swing which is needed in order to keep the synchronism during acceleration is too big to have the SPS cavities deliver enough voltage for all frequencies. For that reason a new technique of fixed frequency acceleration was used. With this technique up to 70% of the injected beam could be captured and accelerated up to the extraction energy, the equivalent of 2.2 1010 charges. The beam was extracted over a 5 sec. long spill and was then delivered to different experiments at the same time
High intensity proton beams in a multi-cycled SPS
The SPS ran for 247 days during 1994; 64% of this was with high intensity proton beam for physics data taking in the Fixed Target mode of operation, 12% was for a lead run at the end of the year, with the remaining 24% spent in setting up and machine development. The SPS supplied LEP with 8 bunches of electrons and 8 bunches of positrons either in the 14.4 or 19.2 seconds interleaved cycling mode during the operation with protons or lead ions respectively. The new record peak intensity during the year was 3.9x1013 protons per pulse at 450GeV. A total of 11x1018 proton were delivered to all targets, with an overall average during physics of 2.5x1013 protons per pulse at 450GeV. Some 6x1018 protons were delivered to both neutrino experiments
The SPS as lead-ion accelerator
In 1995 the CERN SPS was used during two months to accelerate fully stripped ions of the Pb208 isotope from the equivalent proton momentum of 13 GeV/c to 400 GeV/c. The radio frequency swing which is needed in order to keep the synchronism during acceleration is too big to have the SPS cavities deliver enough voltage for all frequencies. In a first stage, the beam is accelerated from 13 GeV/c to 26 GeV/c using the fixed frequency mode. During this stage the beam is grouped in four 2msec batches, separated by 3msec holes during which the frequency is changed in order to keep synchronism. At 26 GeV the beams are de-bunched and recaptured in order to fill the 3msec holes. From there on the lead ions are then accelerated up to 400 GeV/c with the normal frequency program. The de-bunching and recapture at 26 GeV improved the effective spill at extraction by a factor of three. Intensities up to 3.9 1010 charges could be obtained at 400 GeV/c. The total efficiency of the two RF captures was 64%
PHF3 regulates neuronal gene expression through the Pol II CTD reader domain SPOC
The C-terminal domain (CTD) of the largest subunit of RNA polymerase II (Pol II) is a regulatory hub for transcription and RNA processing. Here, we identify PHD-finger protein 3 (PHF3) as a regulator of transcription and mRNA stability that docks onto Pol II CTD through its SPOC domain. We characterize SPOC as a CTD reader domain that preferentially binds two phosphorylated Serine-2 marks in adjacent CTD repeats. PHF3 drives liquid-liquid phase separation of phosphorylated Pol II, colocalizes with Pol II clusters and tracks with Pol II across the length of genes. PHF3 knock-out or SPOC deletion in human cells results in increased Pol II stalling, reduced elongation rate and an increase in mRNA stability, with marked derepression of neuronal genes. Key neuronal genes are aberrantly expressed in Phf3 knock-out mouse embryonic stem cells, resulting in impaired neuronal differentiation. Our data suggest that PHF3 acts as a prominent effector of neuronal gene regulation by bridging transcription with mRNA decay
Complex Loci in Human and Mouse Genomes
Mammalian genomes harbor a larger than expected number of complex loci, in which multiple genes are coupled by shared transcribed regions in antisense orientation and/or by bidirectional core promoters. To determine the incidence, functional significance, and evolutionary context of mammalian complex loci, we identified and characterized 5,248 cis–antisense pairs, 1,638 bidirectional promoters, and 1,153 chains of multiple cis–antisense and/or bidirectionally promoted pairs from 36,606 mouse transcriptional units (TUs), along with 6,141 cis–antisense pairs, 2,113 bidirectional promoters, and 1,480 chains from 42,887 human TUs. In both human and mouse, 25% of TUs resided in cis–antisense pairs, only 17% of which were conserved between the two organisms, indicating frequent species specificity of antisense gene arrangements. A sampling approach indicated that over 40% of all TUs might actually be in cis–antisense pairs, and that only a minority of these arrangements are likely to be conserved between human and mouse. Bidirectional promoters were characterized by variable transcriptional start sites and an identifiable midpoint at which overall sequence composition changed strand and the direction of transcriptional initiation switched. In microarray data covering a wide range of mouse tissues, genes in cis–antisense and bidirectionally promoted arrangement showed a higher probability of being coordinately expressed than random pairs of genes. In a case study on homeotic loci, we observed extensive transcription of nonconserved sequences on the noncoding strand, implying that the presence rather than the sequence of these transcripts is of functional importance. Complex loci are ubiquitous, host numerous nonconserved gene structures and lineage-specific exonification events, and may have a cis-regulatory impact on the member genes
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