Application of rumen and anaerobic sludge microbes for bio harvesting from lignocellulosic biomass

© 2019 Elsevier Ltd This study investigated the production of biogas, volatile fatty acids (VFAs), and other soluble organic from lignocellulosic biomass by two microbial communities (i.e. rumen fluid and anaerobic sludge). Four types of abundant lignocellulosic biomass (i.e. wheat straw, oaten hay, lurence hay and corn silage)found in Australia were used. The results show that rumen microbes produced four-time higher VFAs level than that of anaerobic sludge reactors, indicating the possible application of rumen microorganism for VFAs generation from lignocellulosic biomass. VFA production in the rumen fluid reactors was probably due to the presence of specific hydrolytic and acidogenic bacteria (e.g. Fibrobacter and Prevotella). VFA production corroborated from the observation of pH drop in the rumen fluid reactors indicated hydrolytic and acidogenic inhibition, suggesting the continuous extraction of VFAs from the reactor. Anaerobic sludge reactors on the other hand, produced more biogas than that of rumen fluid reactors. This observation was consistent with the abundance of methanogens in anaerobic sludge inoculum (3.98% of total microbes)compared to rumen fluid (0.11%). VFA production from lignocellulosic biomass is the building block chemical for bioplastic, biohydrogen and biofuel. The results from this study provide important foundation for the development of engineered systems to generate VFAs from lignocellulosic biomass

Dolor posoperatorio en craneotomía

In the postoperative period, 47% to 75% of the patients report some degree of pain. This study aimed to evaluate pain in the pre and postoperative period of patients submitted to craniotomy. This prospective research was carried out at the neurosurgery unit of a large Brazilian hospital. For a quantitative evaluation of pain, the verbal numeric 0 - 10 rating scale was used. Forty patients with a mean age of 36 years were evaluated. In the preoperative period, 34 (85%) patients indicated headache as the main cause of pain. In the postoperative period, 37 (93%) patients complained of pain while three (7%) reported absence of pain. Pain peaks were observed on the 2nd postoperative day, when 12 (32%) of the patients reported severe pain and 10 (27%) moderate pain. Absence of severe pain occurred after the 8th postoperative day. It was concluded that protocols of analgesia in craniotomy are needed, such as training nurses to better evaluate and handle pain.En el periodo postoperatorio, entre el 47% y el 75% de los pacientes relatan algún grado de dolor. Los objetivos de este trabajo fueron evaluar el dolor en el pre y postoperatorio de pacientes sometidos a craneotomía. Este estudio prospectivo fue realizado en la unidad de neurocirugía del Hospital São Paulo, Brasil. Para una evaluación cuantitativa del dolor se utilizó la escala numérica verbal graduada de 0 a 10. Fueron evaluados 40 pacientes con edad mediana de 36 años. En el preoperatorio 34 (85%) pacientes, reportaran cefalea como la principal causa del dolor. En el postoperatorio, 37 (93%) pacientes se quejaron de dolor, mientras 3 (7%) pacientes indicaron ausencia de dolor. El pico de dolor fue observado en el segundo día postoperatorio, cuando 12 (32%) pacientes reportaron dolor grave y 10 (27%) moderado. La ausencia de dolor grave ocurrió después del 8º día postoperatorio. Se concluyó que son necesarios protocolos de analgesia en craneotomía, tales como el entrenamiento de enfermeros para mejor evaluar y manejar el dolor.No pós-operatório, 47 a 75% dos pacientes relatam algum grau de dor. O objetivo deste trabalho foi avaliar a dor no pré e pós-operatório de pacientes submetidos a craniotomia. Estudo prospectivo, realizado na unidade de neurocirurgia do Hospital São Paulo. Para avaliação quantitativa de dor, foi utilizada a escala numérica verbal, graduada de 0 a 10. Foram avaliados 40 pacientes, com idade mediana de 36 anos. No pré-operatório, 34 (85%) pacientes relataram cefaléia como a principal causa de dor. No pós-operatório, 37 (93%) pacientes queixaram-se de dor e 3 (7%) pacientes referiram ausência de dor. O pico da dor foi observado no 2º pós-operatório, quando 16 (40%) dos pacientes referiram dor intensa e 11 (28%) queixaram-se de dor moderada. Ausência de dor intensa ocorreu após 6º pós-operatório. Concluí-se que há necessidade de protocolos de analgesia em craniotomia, como treinamento para os enfermeiros para melhor avaliação e manejo da dor.Hospital Israelita Albert EinsteinUniversidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

Room temperature chiral magnetic skyrmion in ultrathin magnetic nanostructures

Magnetic skyrmions are chiral spin structures with a whirling configuration. Their topological properties, nanometer size and the fact that they can be moved by small current densities have opened a new paradigm for the manipulation of magnetisation at the nanoscale. To date, chiral skyrmion structures have been experimentally demonstrated only in bulk materials and in epitaxial ultrathin films and under external magnetic field or at low temperature. Here, we report on the observation of stable skyrmions in sputtered ultrathin Pt/Co/MgO nanostructures, at room temperature and zero applied magnetic field. We use high lateral resolution X-ray magnetic circular dichroism microscopy to image their chiral N\'eel internal structure which we explain as due to the large strength of the Dzyaloshinskii-Moriya interaction as revealed by spin wave spectroscopy measurements. Our results are substantiated by micromagnetic simulations and numerical models, which allow the identification of the physical mechanisms governing the size and stability of the skyrmions.Comment: Submitted version. Extended version to appear in Nature Nanotechnolog

Cold gas accretion in galaxies

Evidence for the accretion of cold gas in galaxies has been rapidly accumulating in the past years. HI observations of galaxies and their environment have brought to light new facts and phenomena which are evidence of ongoing or recent accretion: 1) A large number of galaxies are accompanied by gas-rich dwarfs or are surrounded by HI cloud complexes, tails and filaments. It may be regarded as direct evidence of cold gas accretion in the local universe. It is probably the same kind of phenomenon of material infall as the stellar streams observed in the halos of our galaxy and M31. 2) Considerable amounts of extra-planar HI have been found in nearby spiral galaxies. While a large fraction of this gas is produced by galactic fountains, it is likely that a part of it is of extragalactic origin. 3) Spirals are known to have extended and warped outer layers of HI. It is not clear how these have formed, and how and for how long the warps can be sustained. Gas infall has been proposed as the origin. 4) The majority of galactic disks are lopsided in their morphology as well as in their kinematics. Also here recent accretion has been advocated as a possible cause. In our view, accretion takes place both through the arrival and merging of gas-rich satellites and through gas infall from the intergalactic medium (IGM). The infall may have observable effects on the disk such as bursts of star formation and lopsidedness. We infer a mean ``visible'' accretion rate of cold gas in galaxies of at least 0.2 Msol/yr. In order to reach the accretion rates needed to sustain the observed star formation (~1 Msol/yr), additional infall of large amounts of gas from the IGM seems to be required.Comment: To appear in Astronomy & Astrophysics Reviews. 34 pages. Full-resolution version available at http://www.astron.nl/~oosterlo/accretionRevie

Gene duplication and fragmentation in the zebra finch major histocompatibility complex

BACKGROUND: Due to its high polymorphism and importance for disease resistance, the major histocompatibility complex (MHC) has been an important focus of many vertebrate genome projects. Avian MHC organization is of particular interest because the chicken Gallus gallus, the avian species with the best characterized MHC, possesses a highly streamlined minimal essential MHC, which is linked to resistance against specific pathogens. It remains unclear the extent to which this organization describes the situation in other birds and whether it represents a derived or ancestral condition. The sequencing of the zebra finch Taeniopygia guttata genome, in combination with targeted bacterial artificial chromosome (BAC) sequencing, has allowed us to characterize an MHC from a highly divergent and diverse avian lineage, the passerines. RESULTS: The zebra finch MHC exhibits a complex structure and history involving gene duplication and fragmentation. The zebra finch MHC includes multiple Class I and Class II genes, some of which appear to be pseudogenes, and spans a much more extensive genomic region than the chicken MHC, as evidenced by the presence of MHC genes on each of seven BACs spanning 739 kb. Cytogenetic (FISH) evidence and the genome assembly itself place core MHC genes on as many as four chromosomes with TAP and Class I genes mapping to different chromosomes. MHC Class II regions are further characterized by high endogenous retroviral content. Lastly, we find strong evidence of selection acting on sites within passerine MHC Class I and Class II genes. CONCLUSION: The zebra finch MHC differs markedly from that of the chicken, the only other bird species with a complete genome sequence. The apparent lack of synteny between TAP and the expressed MHC Class I locus is in fact reminiscent of a pattern seen in some mammalian lineages and may represent convergent evolution. Our analyses of the zebra finch MHC suggest a complex history involving chromosomal fission, gene duplication and translocation in the history of the MHC in birds, and highlight striking differences in MHC structure and organization among avian lineages

Cholesterol Perturbation in Mice Results in p53 Degradation and Axonal Pathology through p38 MAPK and Mdm2 Activation

Perturbation of lipid metabolism, especially of cholesterol homeostasis, can be catastrophic to mammalian brain, as it has the highest level of cholesterol in the body. This notion is best illustrated by the severe progressive neurodegeneration in Niemann-Pick Type C (NPC) disease, one of the lysosomal storage diseases, caused by mutations in the NPC1 or NPC2 gene. In this study, we found that growth cone collapse induced by genetic or pharmacological disruption of cholesterol egress from late endosomes/lysosomes was directly related to a decrease in axonal and growth cone levels of the phosphorylated form of the tumor suppressor factor p53. Cholesterol perturbation-induced growth cone collapse and decrease in phosphorylated p53 were reduced by inhibition of p38 mitogen-activated protein kinase (MAPK) and murine double minute (Mdm2) E3 ligase. Growth cone collapse induced by genetic (npc1−/−) or pharmacological modification of cholesterol metabolism was Rho kinase (ROCK)-dependent and associated with increased RhoA protein synthesis; both processes were significantly reduced by P38 MAPK or Mdm2 inhibition. Finally, in vivo ROCK inhibition significantly increased phosphorylated p53 levels and neurofilaments in axons, and axonal bundle size in npc1−/− mice. These results indicate that NPC-related and cholesterol perturbation-induced axonal pathology is associated with an abnormal signaling pathway consisting in p38 MAPK activation leading to Mdm2-mediated p53 degradation, followed by ROCK activation. These results also suggest new targets for pharmacological treatment of NPC disease and other diseases associated with disruption of cholesterol metabolism