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41.
Tomasz B. Falkowski José Raúl Vázquez-Pérez Adolfo Chankin Atzin Yetlanezi Campos-Beltrán José L. Rangel-Salazar Jonathan B. Cohen Stewart A.W. Diemont 《Biotropica》2020,52(6):1242-1252
Evidence regarding the ability of agroforests to conserve biological diversity has been mixed; they tend to maintain avian communities with species richness similar to that of undisturbed forest ecosystems but generally do not completely preserve community composition. Using a combination of occupancy modeling and non-metric multidimensional scaling on point-count data, we assessed changes in avian community diversity and composition along a successional gradient in traditional Lacandon Maya agroforests and compared them to protected areas in the region. Bird species richness and diversity in Lacandon agroforests peaked in early secondary forest stages. These agroforests' mean Shannon–Weiner diversity was 5% higher than that of nearby protected areas, but their species richness was similar. Community composition in Lacandon agroforests changed throughout succession, with earlier stages supporting communities distinctly characterized by generalist species, while subsequent, less-intensively managed stages tended to support more forest-dwellers. The bird community observed in even the most mature secondary forest stages in Lacandon agroforests differed from that of undisturbed rain forest ecosystems. These results demonstrate the potential of traditional Lacandon agroforestry management to conserve avian biodiversity while ensuring food sovereignty for farmers. However, because the community composition of early-successional stages was different than later stages, shortening fallow cycles and reducing forest cover to increase agricultural production will limit the species this system can support. This study illustrates the value of incorporating traditional agroecosystems into conservation planning as well as maintaining protected areas, because the latter serve as refugia for species that require undisturbed forest habitat in an agroecological matrix. 相似文献
42.
Natanael Zarco Elizabeth Bautista Manola Cuéllar Paula Vergara Paola Flores-Rodriguez Raúl Aguilar-Roblero José Segovia 《The journal of histochemistry and cytochemistry》2013,61(10):731-748
Growth arrest specific 1 (GAS1) is a pleiotropic protein that induces apoptosis and cell arrest in different tumors, but it is also involved in the development of the nervous system and other tissues and organs. This dual ability is likely caused by its capacity to interact both by inhibiting the intracellular signaling cascade induced by glial cell-line derived neurotrophic factor and by facilitating the activity of the sonic hedgehog pathway. The presence of GAS1 mRNA has been described in adult mouse brain, and here we corroborated this observation. We then proceeded to determine the distribution of the protein in the adult central nervous system (CNS). We detected, by western blot analysis, expression of GAS1 in olfactory bulb, caudate-putamen, cerebral cortex, hippocampus, mesencephalon, medulla oblongata, cerebellum, and cervical spinal cord. To more carefully map the expression of GAS1, we performed double-label immunohistochemistry and noticed expression of GAS1 in neurons in all brain areas examined. We also observed expression of GAS1 in astroglial cells, albeit the pattern of expression was more restricted than that seen in neurons. Briefly, in the present article, we report the widespread distribution and cellular localization of the GAS1 native protein in adult mammalian CNS. 相似文献
43.
Culture Media Statistical Optimization for Biomass Production of a Ligninolytic Fungus for Future Rice Straw Degradation 总被引:1,自引:0,他引:1
Viviana Sarria-Alfonso John Sánchez-Sierra Mauricio Aguirre-Morales Ivonne Gutiérrez-Rojas Nubia Moreno-Sarmiento Raúl A. Poutou-Piñales 《Indian journal of microbiology》2013,53(2):199-207
The main objective of this study was to optimize a culture media for low scale biomass production of Pleurotus spp. Future applications of this optimization will be implemented for “in situ” rice straw degradation, increase soil nutrients availability, and lower residue and rice culture management costs. Soil samples were taken from different points in six important rice production cities in Colombia. For carbon and nitrogen source selection a factorial 42 design was carried out. The Plackett-Burman design permitted to detect carbon, nitrogen and inducer effects on fungus growth (response variable for all designs). This optimization was carried out by a Box-Behnken design. Finally a re-optimization assay for glucose concentration was performed by means of a One Factor design. Only 4/33 (12 %) isolates showed and important laccase or manganese peroxidase activity compared to Pleurotus ostreatus (HPB/P3). We obtained an increased biomass production in Pleurotus spp. (T1.1.) with glucose, followed by rice husk. Rice straw was considered an inducing agent for lignin degradation. Glucose was a significant component with positive effects, whereas Tween 80 and pH had negative effects. On the contrary, rice husk, yeast extract and CaCl2 were not significant components for increase the biomass production. Final media composition consisted of glucose 25 g L?1, yeast extract 5 g L?1, Tween 80 0.38 % (v/v), Rice husk 10 g L?1, CaCl2 1 g L?1, and pH 4.88 ± 0.2. The Box-Behnken polynomial prediction resulted to be lower than the experimental validation of the model (6.59 vs. 6.91 Log10 CFU ml?1 respectively). 相似文献
44.
Marcelo Ozu H. Ariel Alvarez Andrés N. McCarthy J. Raúl Grigera Osvaldo Chara 《European biophysics journal : EBJ》2013,42(4):223-239
Present knowledge obtained by molecular dynamics (MD) simulation studies regarding the dynamics of water, both in the vicinity of biological membranes and within the proteinaceous water channels, also known as aquaporins (AQPs), is reviewed. A brief general summary of the water models most extensively employed in MD simulations (SPC, SPC/E, TIP3P, TIP4P), indicating their most relevant pros and cons, is likewise provided. Structural considerations of water are also discussed, based on different order parameters, which can be extracted from MD simulations as well as from experiments. Secondly, the behaviour of water in the neighbourhood of membranes by means of molecular dynamics simulations is addressed. Consequently, the comparison with previous experimental evidence is pointed out. In living cells, water is transported across the plasma membrane through the lipid bilayer and the aforementioned AQPs, which motivates this review to focus mostly on MD simulation studies of water within AQPs. Relevant contributions explaining peculiar properties of these channels are discussed, such as selectivity and gating. Water models used in these studies are also summarised. Finally, based on the information presented here, further MD studies are encouraged. 相似文献
45.
Toshihide Nishimura Mee Ra Rhue Akihiro Okitani Hiromichi Kato 《Bioscience, biotechnology, and biochemistry》2013,77(9):2323-2330
The changes in both taste and taste components of beef, pork, and chicken during storage were examined.The brothy taste intensity of pork and chicken was significantly stronger after conditioning than before. On the other hand, for beef, there was no significant difference in the brothy taste intensity before or after conditioning. The analysis of major taste components showed that the levels of free amino acids in all meats were higher after conditioning than before. The differences in the levels of free amino acids before versus after conditioning were large in pork and chicken and very small in beef. Oligopeptide levels were lower in beef after conditioning than before, but they were higher in pork and chicken after conditioning than before. These results corresponded to results of the sensory evaluation studies described above, indicating that free amino acids and oligopeptides contributed to the improvement of meat taste during storage. 相似文献
46.
47.
S. El Issami M.A. Bsiss A. Matrane S. Hiroual S. Bennani Doubli N. Ben Raïs Aouad 《Médecine Nucléaire》2013,37(10-11):520-525
The presence of a parathyroid gland in ectopic position constitutes one of the leading causes of surgery failure. For this purpose, scintigraphy takes a major place in the anatomical localization of pathological parathyroid and so facilitates its treatment. The advent of hybrid cameras combining single photon emission tomography to CT (SPECT/CT) has further strengthened the contribution of this imaging modality in the precise localization of ectopic parathyroid and its anatomical relationships. The objective of our work is to illustrate the interest of hybrid imaging SPECT/CT, compared to planar scintigraphy and ultrasounds within the framework of primary hyperparathyroidism, particularly ectopic situation through three cases. 相似文献
48.
Carlos Torner Luis Sánchez-Hurtado Raúl Aguilar-Roblero 《Biological Rhythm Research》2013,44(5):538-545
In spite of the clear evidences for the blockade of dopaminergic D2 receptors as the mechanism of action for haloperidol-induced catalepsy, the contribution of pharmacokinetic and pharmacodynamic aspects on the diurnal modulation of haloperidol-induced catalepsy is controversial. We studied the diurnal variations of striatal dopamine receptors and its relation with catalepsy diurnal variations. The [3 H]-spiperone binding to dopamine receptors had a clear rhythm with a peak at 00:00 to 03:00 h, and a trough at 12:00 to 18:00 h. Haloperidol-produced catalepsy measured with the four-cork test, also showed a clear rhythm, with a peak at 00:00 h and trough at 9:00 h. The dose-response curves at peak and trough of catalepsy had the same ED 50 (0.12 mg), with time-related changes in the maximal effect. Similar diurnal variations between catalepsy and dopamine receptor binding, indicate a relevant role of temporal pharmacodynamics of haloperidol on the modulation of its behavioral effects. 相似文献
49.
50.
Drew P. Pulsifer Akhlesh Lakhtakia Mahesh S. Narkhede Michael J. Domingue Beverly G. Post Jayant Kumar Raúl J. Martín-Palma 《仿生工程学报(英文版)》2013,10(2):129-138
Through a bioreplication approach, we have fabricated artificial visual decoys for the invasive species Agrilus planipennis—commonly known as the Emerald Ash Borer (EAB). The mating behavior of this species involves an overflying EAB male pouncing on an EAB female at rest on an ash leaflet before copulating. The male spots the female on the leaflet by visually detecting the iridescent green color of the female's elytra. As rearing EAB and then deploying dead females as decoys for trapping is both arduous and inconvenient, we decided to fabricate artificial decoys. We used a dead female to make a negative die of nickel and a positive die of epoxy. Decoys were then made by first depositing a quarter-wave-stack Bragg reflector on a polymer sheet and then stamping it with a pair of matched negative and positive dies to take the shape of the upper surface of an EAB female. As nearly 100 artificial decoys were fabricated from just one EAB female, this bioreplication process is industrially scalable. Preliminary results from a field trapping test are indicative of success. 相似文献