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Boron nitride nanotube peapods (BNNT-peapod) are composed of linear chains of C60molecules encapsulated inside BNNTs, they were first synthesized in 2003. In this work, we investigated the mechanical response and fracture dynamics of BNNT-peapods under ultrasonic velocity impacts (from 1 km s-1up to 6 km s-1) against a solid target. We carried out fully atomistic reactive molecular dynamics simulations using a reactive force field. We have considered the case of horizontal and vertical shootings. Depending on the velocity values, we observed tube bending, tube fracture, and C60ejection. Furthermore, the nanotube unzips for horizontal impacts at certain speeds, forming bi-layer nanoribbons 'incrusted' with C60molecules. The methodology used here is applicable to other nanostructures. We hope it motivates other theoretical investigations on the behavior of nanostructures at ultrasonic velocity impacts and aid in interpreting future experimental results. It should be stressed that similar experiments and simulations were carried out on carbon nanotubes trying to obtain nanodiamonds. The present study expands these investigations to include BNNT.

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Envenomation via snakebites occurs largely in areas where it is harder to access the hospital. Its mortality rate and sequelae acquired by the survivors symbolize a big challenge for antivenom therapy. In particular, the homologous phospholipase A2 (Lys49-PLA2) proteins can induce myonecrosis and are not effectively neutralized by current treatments. Thus, by taking advantage of crystallographic structures of Bothrops moojeni Lys49-PLA2 complexed with VRD (varespladib) and AIN (aspirin), a quantum biochemistry study based on the molecular fractionation with conjugate cap scheme within the density functional theory formalism is performed to unveil these complexes' detailed interaction energies. The calculations revealed that important interactions between ligands and the Lys49-PLA2 pocket could occur up to a pocket radius of r = 6.5 (5.0 Å) for VRD (AIN), with the total interaction energy of the VRD ligand being higher than that of the AIN ligand, which is well-correlated with the experimental binding affinity. Furthermore, we have identified the role played by the amino acids LYS0069, LYS0049, LEU0005, ILE0009, CYS0029, GLY0030, HIS0048, PRO0018, ALA0019, CYS0045, TYR0052, TYR0022, PRO0125*, and PHE0126* (LYS0069, LYS0049, GLY0032, LEU0002, and LEU0005) in the VRD↔Lys49-PLA2 (AIN↔Lys49-PLA2) complex. Our simulations are a valuable tool to support the big challenge for neutralizing the damages in victims of snakebites.

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Previous studies have shown the porphobilinogen synthase (PBGS) zinc-binding mechanism and its conservation among the living cells. However, the precise molecular interaction of zinc with the active center of the enzyme is unknown. In particular, quantum chemistry techniques within the density functional theory (DFT) framework have been the key methodology to describe metalloproteins, when one is looking for a compromise between accuracy and computational feasibility. Considering this, we used DFT-based models within the molecular fractionation with conjugate caps scheme to evaluate the binding energy features of zinc interacting with the human PBGS. Besides, phylogenetic and clustering analyses were successfully employed in extracting useful information from protein sequences to identify groups of conserved residues that build the ions-binding site. Our results also report a conservative assessment of the relevant amino acids, as well as the benchmark analysis of the calculation models used. The most relevant intermolecular interactions in Zn2+-PBGS are due to the amino acids CYS0122, CYS0124, CYS0132, ASP0169, SER0168, ARG0221, HIS0131, ASP0120, GLY0133, VAL0121, ARG0209, and ARG0174. Among these residues, we highlighted ASP0120, GLY0133, HIS0131, SER0168, and ARG0209 by co-occurring in all clusters generated by unsupervised clustering analysis. On the other hand, the triple cysteines at 2.5 Å from zinc (CYS0122, CYS0124, and CYS0132) have the highest energy attraction and are absent in the taxa Viridiplantae, Sar, Rhodophyta, and some Bacteria. Additionally, the performance of the DFT-based models shows that the processing time-dependence is more associated with the choice of the basis set than the exchange-correlation functional.

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The behavior of nanostructures under high strain-rate conditions has been the object of theoretical and experimental investigations in recent years. For instance, it has been shown that carbon and boron nitride nanotubes can be unzipped into nanoribbons at high-velocity impacts. However, the response of many nanostructures to high strain-rate conditions is still unknown. In this work, we have investigated the mechanical behavior of carbon (CNS) and boron nitride nanoscrolls (BNS) colliding against solid targets at high velocities, using fully atomistic reactive (ReaxFF) molecular dynamics (MD) simulations. CNS (BNS) are graphene (boron nitride) membranes rolled up into papyrus-like structures. Their open-ended topology leads to unique properties not found in their close-ended analogs, such as nanotubes. Our results show that collision products are mainly determined by impact velocities and by two orientation angles, which define the position of the scroll (i) axis and (ii) open edge relative to the target. Our MD results showed that for appropriate velocities and orientations, large-scale deformations and nanoscroll fractures could occur. We also observed unscrolling (scrolls going back to quasi-planar membranes), scroll unzipping into nanoribbons, and significant reconstruction due to breaking and/or formation of new chemical bonds. For particular edge orientations and velocities, conversion from open to close-ended topology is also possible, due to the fusion of nanoscroll walls.

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Mycoplasma gallisepticum causes coughing, ocular and nasal discharge, reduction in feed intake, lower and uneven growth, decline in egg production and quality, and increase in mortality. Among the attenuated vaccination strains, MGF can reduce clinical signs and lesions in layer hens, stimulate immune responses of cellular and humoral basis, act as an instrument of competitive exclusion in relation to field strains, and reduce the use of antimicrobials. This study aimed to investigate the effects of attenuated MG F-strain vaccination on egg quality in 3 groups of 30 hens each, being one control and 2 vaccinated. Vaccination was applied by ocular route at 8 and 12 wk of age. Comparisons were made among unvaccinated hens; vaccinated at 8 wk of age; and vaccinated at 8 and 12 wk of age. There were no statistical differences in eggshell thickness and weight among groups. Eggs from twice vaccinated birds yielded a Haugh unit significantly lower than the other groups without affecting egg classification. There was no significant difference in ELISA results between the vaccinated groups.

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Recently, Geblinger et al. [Nat. Nanotechnol. 3, 195 (2008)] reported the experimental realization of carbon nanotube S-like shaped nanostructures, the so-called carbon nanotube serpentines. We report here results from multimillion fully atomistic molecular dynamics simulations of their formation. We consider one-µm-long carbon nanotubes placed on stepped substrates with and without a catalyst nanoparticle on the top free end of the tube. A force is applied to the upper part of the tube during a short period of time and turned off; then the system is set free to evolve in time. Our results show that these conditions are sufficient to form robust serpentines and validates the general features of the "falling spaghetti model" proposed to explain their formation.

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Tissue banks around the world store human cartilage obtained from cadaveric donors for use in diverse reconstructive surgical procedures. To ensure this tissue is sterile at the time of distribution, tissues may be sterilized by ionizing radiation. In this work, we evaluate the physical changes in deep frozen costal cartilage (-70 °C) or costal cartilage preserved in high concentrations of glycerol (>98 %) followed by a terminal sterilization process using ionizing radiation, at 3 different doses (15, 25 and 50 kGy). Tension and compression tests were carried out to determine the mechanical changes related both to the different preservation methods and irradiation doses. For both methods of preservation, tension strength was increased by about 24 %, when cartilage tissue was irradiated with 15 kGy. Deep frozen samples, when irradiated with 25 or 50 kGy, had a decrease in their mechanical performance, albeit to a lesser extent than when tissues were preserved in high concentration of glycerol and equally irradiated. In conclusion, processing in high concentration of glycerol did not increase tissue protection against radiation damage; while cartilage preserved in high concentrations of glycerol withstands radiation up to 25 kGy, deep frozen human costal cartilage may be sterilized with a doses up to 50 kGy without significant mechanical impact.

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The physiological parameters that could be reference for trustful diagnosis and prognosis of prostate disorders in dogs were obtained. Thirty six intact male dogs without clinical signs of neither prostatic nor reproductive disorders were allocated according the age in three groups. These animals were submitted to semen manual collection for microbiological exams; transabdominal ultrasonography to evaluate dimensions, ecogenicity, and texture of prostatic parenchyma and aspirative puncture with fine needle for cytological and microbiological analyses. Ultrasonography revealed that the predominant prostatic shape was round with regular surface. Dimensions varied according to age, being small in young animals and large in old ones. There was a positive correlation between prostatic dimensions and body weight. Microbiological exams detected microorganisms on seminal plasma from 11 dogs and prostate tissue aspirated from 10 animals, although they were healthy. Cytology did not reveal any inflammatory, proliferative, or neoplasic alteration in young and middle age dogs, but in three older dogs signs of hyperplasia/hypertrophy was found. It was observed positive correlation between age and cellular area but a negative correlation was observed between nucleus:cytoplasm ratio and craniocaudal dimension.

Obtiveram-se parâmetros fisiológicos que pudessem ser utilizados como referência para diagnóstico e prognóstico confiáveis de doença prostática em cães. Trinta e seis cães, sem sinais clínicos de doença prostática ou distúrbios reprodutivos, foram distribuídos em três grupos de acordo com a idade.Os animais foram submetidos à colheita manual de sêmen para exames microbiológicos, à ultrassonografia transabdominal, para avaliar as dimensões, a ecogenicidade e a ecotextura prostática, e à punção aspirativa com agulha fina, para análise citológica e microbiológica. A ultrassonografia revelou que a forma predominante da próstata foi globosa, com superfície de contorno regular. As dimensões variaram de acordo com a idade, sendo pequena em animais jovens e grande nos animais idosos. Houve correlação positiva entre as dimensões prostáticas e o peso corporal. Os exames microbiológicos detectaram microrganismos no plasma seminal de 11 cães e no tecido prostático aspirado de 10 animais, embora eles fossem saudáveis. A citologia não revelou nenhuma alteração inflamatória, proliferativa ou neoplásica nos cães jovens e de meia idade, mas, em três cães idosos foram encontrados sinais de hiperplasia/hipertrofia. Foi observada correlação positiva entre a idade e a área celular e correlação negativa entre a relação núcleo:citoplasma e a dimensão craniocaudal.

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The physiological parameters that could be reference for trustful diagnosis and prognosis of prostate disorders in dogs were obtained. Thirty six intact male dogs without clinical signs of neither prostatic nor reproductive disorders were allocated according the age in three groups. These animals were submitted to semen manual collection for microbiological exams; transabdominal ultrasonography to evaluate dimensions, ecogenicity, and texture of prostatic parenchyma and aspirative puncture with fine needle for cytological and microbiological analyses. Ultrasonography revealed that the predominant prostatic shape was round with regular surface. Dimensions varied according to age, being small in young animals and large in old ones. There was a positive correlation between prostatic dimensions and body weight. Microbiological exams detected microorganisms on seminal plasma from 11 dogs and prostate tissue aspirated from 10 animals, although they were healthy. Cytology did not reveal any inflammatory, proliferative, or neoplasic alteration in young and middle age dogs, but in three older dogs signs of hyperplasia/hypertrophy was found. It was observed positive correlation between age and cellular area but a negative correlation was observed between nucleus:cytoplasm ratio and craniocaudal dimension.(AU)

Obtiveram-se parâmetros fisiológicos que pudessem ser utilizados como referência para diagnóstico e prognóstico confiáveis de doença prostática em cães. Trinta e seis cães, sem sinais clínicos de doença prostática ou distúrbios reprodutivos, foram distribuídos em três grupos de acordo com a idade.Os animais foram submetidos à colheita manual de sêmen para exames microbiológicos, à ultrassonografia transabdominal, para avaliar as dimensões, a ecogenicidade e a ecotextura prostática, e à punção aspirativa com agulha fina, para análise citológica e microbiológica. A ultrassonografia revelou que a forma predominante da próstata foi globosa, com superfície de contorno regular. As dimensões variaram de acordo com a idade, sendo pequena em animais jovens e grande nos animais idosos. Houve correlação positiva entre as dimensões prostáticas e o peso corporal. Os exames microbiológicos detectaram microrganismos no plasma seminal de 11 cães e no tecido prostático aspirado de 10 animais, embora eles fossem saudáveis. A citologia não revelou nenhuma alteração inflamatória, proliferativa ou neoplásica nos cães jovens e de meia idade, mas, em três cães idosos foram encontrados sinais de hiperplasia/hipertrofia. Foi observada correlação positiva entre a idade e a área celular e correlação negativa entre a relação núcleo:citoplasma e a dimensão craniocaudal.(AU)

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Neurocysticercosis (NC), the presence of Taenia solium metacestodes in tissues, is the most frequent and severe parasitic infection of the central nervous system. We investigated the presence of total IgE by an automated chemiluminescence assay in 53 paired cerebrospinal fluid (CSF) and serum samples from patients with NC (P) and in 40 CSF samples from individuals with other neurological disorders as the control group (C). Total IgE concentration ranged from 1.2 to 6.6 IU/ml (mean = 1.4 IU/ml, standard deviation-sd = 1.1 IU/ml) in 28.3% of CSF samples from the P group, a value significantly higher than for the C group ( pound1.0 IU/ml). The serum samples from the P group showed concentrations ranging from 1. 0 to 2330.0 IU/ml (mean = 224.1 IU/ml, sd = 452.1 IU/ml), which were higher than the normal value cited by the manufacturer (<100.0 IU/ml) in 32.1% of the samples. A significant difference was observed in CSF samples from the P and C groups (p = 0.005) and in serum samples from the P group compared to the normal value (p = 0. 005), with sera showing more frequent abnormal results.

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We assayed samples of cerebrospinal fluid (CSF), serum and saliva from patients with neurocysticercoses, control group and individuals with other parasitoses, by ELISA with Taenia crassiceps vesicular fluid antigen (Tcra) and Taenia solium total antigen (Tso) for the detection of antibodies. The sensitivity for IgG-Tcra was 100% for CSF and serum, and 32.0% for saliva; and for IgG-Tso 100% for CSF, 80.0% for serum and 24.% for saliva. Specificity was 100% for CSF and 80.0% for serum with both antigens, and 100% for saliva with Tcra and 87.5% with Tso. The sensitivity and specificity for IgA-Tcra was, respectively, 40.0% and 100% for CSF, 36.0% and 97.1% for serum, and 4.0% and 90.0% for saliva. IgE detection showed 24.0% sensitivity and 97.1% specificity for serum, with no detection in CSF samples. The search for antibodies revealed the presence of IgG > IgA > IgE in CSF, serum and saliva samples, with IgG being present in all phases of the disease, while IgA/IgE were more frequent in the inactive form.

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Neurocysticercosis (NC), i.e., the presence of the larval form of Taenia solium in tissues, is the most frequent and severe infection involving the central nervous system. Paired serum and cerebrospinal fluid (CSF) samples from patients with NC, CSF and serum samples from a control group, and serum samples from patients with other parasitoses were studied by enzyme-linked immunosorbent assay (ELISA) and by immunoblotting with Taenia crassiceps vesicular fluid antigen (Tcra) and Taenia solium total saline antigen (Tso) for the detection of immunoglobulin G antibodies. ELISAs carried out with the Tso and Tcra antigens showed 94.1 and 95.6% sensitivities, respectively, for the detection of antibodies in CSF and 70.6% and 91.2% sensitivities, respectively, for the detection of antibodies in serum, with 100% specificity for the detection of antibodies in CSF and 80% specificity for the detection of antibodies in serum for both antigens. On the basis of the reactivities of the peptides in the samples analyzed, the peptides of

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The adenosine-deaminase (ADA) activity was evaluated in CSF samples from 263 patients with AIDS. An elevated ADA activity in CSF was found in patients with: antibodies to toxoplasmosis, syphilis or cytomegalovirus; Cryptococcus neoformans or their antigens; tuberculous meningitis; lymphoma. There was no statistical difference among all these groups in respect to ADA activity. However, the ADA activity in CSF from AIDS patients without CSF changes other than HIV antibodies, even unspecific changes, was not elevated. This may suggest that ADA is related to AIDS associated pathologies activity rather than to HIV infection itself.

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