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1.
Heliyon ; 10(15): e35373, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39165957

ABSTRACT

This study was on optimization of the cutting processes for corn stalks, which serve as significant sources of biomass and forage. The reduction of cutting force is crucial for enhancing energy efficiency. Cutting velocity rises, which can lead to significant power usage with minimal shear forces. Therefore, the objective is to minimize both the cutting force and power consumption. To address this multi-objective optimization problem, a modified Taguchi method was employed. Chauvenet's criterion was used to assess the validity of statistical scatter in repeated test data. The test samples had an 81 % moisture content. Through analysis of variance (ANOVA), the optimal chopping process parameters were identified as velocity of 4.4 m/s, approach angle of 30°, and feeding angle of 50°. The refined empirical relationships indicated that the cutting force ranges from 180.55 N to 393.37 N, while the cutting power ranges from 16.81 W to 44.05 W. In a single test, the output responses for the optimal parameter set were 26.32 W for power consumption and 242.60 N for cutting force, both are within the estimated range. The considerable scatter observed in repeated test data is likely due to variations in corn stalk thickness. These findings are valuable for the operation of chopping machines, ensuring minimal cutting force and power consumption when handling corn stalks residues.

3.
Front Vet Sci ; 10: 1185454, 2023.
Article in English | MEDLINE | ID: mdl-37252393

ABSTRACT

This study was conducted to determine an approach angle to medial orbitotomy that avoids accidental neurotrauma in mesaticephalic dogs. Medical records of dogs with mesaticephalic skulls that were presented to the veterinary medical teaching hospital for head computed tomography (CT) between September 2021 and February 2022 were reviewed. Descriptive data were queried, and CT findings were analyzed. Dogs greater than 20 kg and possessing a disease-free orbitozygomaticomaxillary complex (OZMC) on at least one side of the skull were included in this study. Digital imaging and communications in medicine (DICOM) files of head CT studies were imported into medical modeling software, and the safe approach angle for medial orbitotomy was determined using three-dimensional (3D) computer models and virtual surgical planning (VSP) principles. Angles were measured along the ventral orbital crest (VOC) from the rostral cranial fossa (RCF) to the rostral alar foramen (RAF). The safe approach angle at four points from rostral to caudal along the VOC was measured. The results at each location were reported as mean, median, 95% CI, interquartile ranges, and distribution. The results were statistically different at each location and generally increased from rostral to caudal. The variances between subjects and the differences between locations were large enough to suggest a standard safe approach angle in mesaticephalic dogs cannot be determined and should be measured for each patient. A standardized approach angle to medial orbitotomy is not possible in the mesaticephalic dog. Computer modeling and VSP principles should be implemented as part of the surgical planning process to accurately measure the safe approach angle along the VOC.

4.
Cell Rep ; 37(5): 109922, 2021 11 02.
Article in English | MEDLINE | ID: mdl-34731616

ABSTRACT

Recognition of N-linked glycan at residue N276 (glycan276) at the periphery of the CD4-binding site (CD4bs) on the HIV-envelope trimer is a formidable challenge for many CD4bs-directed antibodies. To understand how this glycan can be recognized, here we isolate two lineages of glycan276-dependent CD4bs antibodies. Antibody CH540-VRC40.01 (named for donor-lineage.clone) neutralizes 81% of a panel of 208 diverse strains, while antibody CH314-VRC33.01 neutralizes 45%. Cryo-electron microscopy (cryo-EM) structures of these two antibodies and 179NC75, a previously identified glycan276-dependent CD4bs antibody, in complex with HIV-envelope trimer reveal substantially different modes of glycan276 recognition. Despite these differences, binding of glycan276-dependent antibodies maintains a glycan276 conformation similar to that observed in the absence of glycan276-binding antibodies. By contrast, glycan276-independent CD4bs antibodies, such as VRC01, displace glycan276 upon binding. These results provide a foundation for understanding antibody recognition of glycan276 and suggest its presence may be crucial for priming immunogens seeking to initiate broad CD4bs recognition.


Subject(s)
AIDS Vaccines/immunology , Broadly Neutralizing Antibodies/immunology , Epitopes , HIV-1/immunology , Polysaccharides/immunology , env Gene Products, Human Immunodeficiency Virus/immunology , AIDS Vaccines/metabolism , Antibody Specificity , Binding Sites, Antibody , Broadly Neutralizing Antibodies/metabolism , Broadly Neutralizing Antibodies/ultrastructure , CD4 Antigens/immunology , CD4 Antigens/metabolism , Cryoelectron Microscopy , HEK293 Cells , HIV-1/metabolism , Humans , Models, Molecular , Polysaccharides/metabolism , Protein Binding , Protein Conformation , Single Molecule Imaging , Structure-Activity Relationship , env Gene Products, Human Immunodeficiency Virus/metabolism
5.
J Virol ; 95(17): e0009421, 2021 08 10.
Article in English | MEDLINE | ID: mdl-34076487

ABSTRACT

The high viral diversity of HIV-1 is a formidable hurdle for the development of an HIV-1 vaccine. Elicitation of broadly neutralizing antibodies (bNAbs) would offer a solution, but so far immunization strategies have failed to efficiently elicit bNAbs. To overcome these obstacles, it is important to understand the immune responses elicited by current HIV-1 envelope glycoprotein (Env) immunogens. To gain more insight, we characterized monoclonal antibodies (MAbs) isolated from rabbits immunized with Env SOSIP trimers based on the clade B isolate AMC008. Four rabbits that were immunized three times with AMC008 trimer developed robust autologous and sporadic low-titer heterologous neutralizing responses. Seventeen AMC008 trimer-reactive MAbs were isolated using antigen-specific single B-cell sorting. Four of these MAbs neutralized the autologous AMC008 virus and several other clade B viruses. When visualized by electron microscopy, the complex of the neutralizing MAbs with the AMC008 trimer showed binding to the gp41 subunit with unusual approach angles, and we observed that their neutralization ability depended on their capacity to induce Env trimer dissociation. Thus, AMC008 SOSIP trimer immunization induced clade B-neutralizing MAbs with unusual approach angles with neutralizing effects that involve trimer destabilization. Optimizing these responses might provide an avenue to the induction of trimer-dissociating bNAbs. IMPORTANCE Roughly 32 million people have died as a consequence of HIV-1 infection since the start of the epidemic, and 1.7 million people still get infected with HIV-1 annually. Therefore, a vaccine to prevent HIV-1 infection is urgently needed. Current HIV-1 immunogens are not able to elicit the broad immune responses needed to provide protection against the large variation of HIV-1 strains circulating globally. A better understanding of the humoral immune responses elicited by immunization with state-of-the-art HIV-1 immunogens should facilitate the design of improved HIV-1 vaccine candidates. We identified antibodies with the ability to neutralize multiple HIV-1 viruses by destabilization of the envelope glycoprotein. Their weak but consistent cross-neutralization ability indicates the potential of this epitope to elicit broad responses. The trimer-destabilizing effect of the neutralizing MAbs, combined with detailed characterization of the neutralization epitope, can be used to shape the next generation of HIV-1 immunogens to elicit improved humoral responses after vaccination.


Subject(s)
AIDS Vaccines/immunology , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , HIV Antibodies/immunology , HIV Infections/immunology , HIV-1/immunology , env Gene Products, Human Immunodeficiency Virus/immunology , AIDS Vaccines/administration & dosage , Animals , Glycoproteins/immunology , HIV Infections/prevention & control , HIV Infections/virology , Humans , Immunization , Protein Multimerization , Rabbits , env Gene Products, Human Immunodeficiency Virus/chemistry
6.
Curr Zool ; 65(4): 467-481, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31413719

ABSTRACT

Angle dependent colors, such as iridescence, are produced by structures present on flower petals changing their visual appearance. These colors have been proposed to act as signals for plant-insect communication. However, there is a paucity of behavioral data to allow for interpretations of how to classify these colors either as a signal or a cue when considering the natural conditions under which pollination occurs. We sampled flowers from 6 plant species across various viewpoints looking for changes in the visual appearance of the petals. Spectral characteristics were measured with different instruments to simulate both the spectral and spatial characteristics of honeybee's vision. We show the presence of color patches produced by angle dependent effects on the petals and the calyx of various species; however, the appearance of the angle dependent color patches significantly varies with viewpoint and would only be resolved by the insect eye at close distances. Behavior experiments with honeybees revealed that pollinators did not use angle dependent colors to drive behavior when presented with novel flower presentations. Results show that angle dependent colors do not comply with the requirements of a signal for plant-pollinator communication since the information transmitted by these colors would be unreliable for potential, free-flying pollination vectors. We thus classify angle dependent colors produced by micro- and ultra-structures as being a cue (a feature which has not evolved for communication), and observe no evidence supporting claims of these angle dependent colors having evolved as visual signal.

7.
J Sports Sci Med ; 17(1): 74-81, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29535580

ABSTRACT

The purpose of this study was to investigate the influence of the task conditions on 20-m side foot-kick accuracy among Swedish first league women's soccer players. Twenty-three players performed three side foot-kick tests under different task conditions: stationary ball using match-relevant ball speed (SBRS) and maximal ball speed (SBMS) and a 5-m run with the ball from different approach angles (0°, 30°, and 60°) to a predetermined position, where passing of the ball on the move was executed using match-relevant ball speed (RBRS). With each test, the players performed 30 side-foot kicks, alternating between kicking legs with the aim of hitting a target stick. The accuracy was determined using video analysis. The side foot-kick accuracy was significantly greater for SBRS, compared to RBRS and SBMS. For all three test variables, the preferred leg displayed greater accuracy. The preferred leg's accuracy was greater for the approach angle of 30° compared to both 0° and 60°. A significant deviation from the target stick was found for the straight-ahead approach, in which the right-foot and left-foot kicks deviated to respectively the left and right of the stick; in contrast, for the approach angle of 60°, the deviation from the target stick was on the opposite side of the approach side for both legs.

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