Three in vitro experimental models received the Birmingham hip resurfacing implant to replicate the total hip joint. The resurfacing head of the implanted models was placed in three different offset positions: in a positive offset, with the same femoral head center and in a negative offset.
The numerical models were validated by correlating numerical and experimental results. Comparing experimental results from the implanted and intact femurs highlights a strain increase of up to 48% in the proximal medial femur region for positive offset and up to 18% in the neutral position. A reduction of 72% for negative offset (valgus position) was also measured experimentally.
A significant change in strain distributions was observed with a resurfacing hip system and increased risk of neck fracture was found using the resurfacing head in positive offset. The iliac bone presents a high decrease in strains that will induce bone loss in the long term. Among the offset positions tested, results suggest that the negative offset (valgus position) and the natural position are the best equilibrated for better long-term results. 相似文献
The methodology of recording and systematization includes the following parameters: coal deposits; climate parameters; roads; rivers; land and surrounding objects; air polluters; water polluters; and soil polluters. Methods for calculating land deformation, air polluter emissions, and noise impact are also presented.
Based on the number and specificity of analyzed data, the paper provides a concept of the IS and an overview of environmental impact of underground coal mine technological units. The concept was used to present the results of a research conducted at the underground coal mine “Soko” in Serbia.
The results of this research can help many potential users realize their goals. Those goals are preventive by nature, since negative environmental impact can be predicted, which enables the environmental protection experts to take appropriate measures. 相似文献
Materials and methods: Eleven healthy right-handed adults participated in this study. With the aid of visual feedback, participants were asked to control the force of abduction of the right index finger to 10%, 20%, 40%, 60%, 80%, and 100% of the maximum voluntary contraction. Single pulse transcranial magnetic stimulation was delivered to the left primary motor cortex region during force control tasks. The averaged actual force output level, background electromyography amplitude, and cortical silent period duration were compared between conditions, and correlation analysis was conducted.
Results: There were significant main effects of target force on background electromyography, and cortical silent period duration; with increased force, the actual force output level and background electromyography gradually increased, while cortical silent period duration gradually decreased. There were significant negative correlations between cortical silent period and force and cortical silent period and background electromyography.
Conclusions: These findings indicate that the excitability of gamma-aminobutyric acidergic inhibitory neural circuits in primary motor cortex decreases in response to increased force output, mediated via increased corticospinal and motoneuron excitability. These results may facilitate understanding of the role of the gamma-aminobutyric acidergic circuit in primary motor cortex in force control, as well as of the mechanism underlying motor dysfunction in stroke-induced palsy, dystonia, and cerebellar ataxia. 相似文献
Aims: This study aims to determine whether Capercaillie vocalizations can be recognized in lek recordings, whether this can be automated using readily available software, and whether the number of calls resulting varies with location, weather conditions, date and time of day.
Methods: Unattended recording devices and semi-automated call classification software were used to record and analyse the display calls of Capercaillie at three known lek sites in Scotland over a two-week period.
Results: Capercaillie calls were successfully and rapidly identified within a data set that included the vocalizations of other bird species and environmental noise. Calls could be readily recognized to species level using a combination of unsupervised software and manual analysis. The number of calls varied by time and date, by recorder/microphone location at the lek site, and with weather conditions. This information can be used to better target future acoustic monitoring and improve the quality of existing traditional lek surveys.
Conclusion: Bioacoustic methods provide a practical and cost-effective way to determine habitat occupancy and activity levels by a vocally distinctive bird species. Following further testing alongside traditional counting methods, it could offer a significant new approach towards more effective monitoring of local population levels for Capercaillie and other species of conservation concern. 相似文献
Aims: To determine which seed species are consumed by Turtle Doves in Mediterranean forest areas.
Methods: Digestive tract contents were identified and evaluated for 222 Turtle Doves shot by hunters during three consecutive years.
Results: Thirty seed species were identified in the diet, but only a few species represented most of the volume and frequency. Wild plant seeds appeared in 65.8% of digestive tracts and showed significant variation between years. Although the main wild seed species consumed each year varied annually, certain species were found in the diet every year in high volume and frequency. Adults showed a more diverse and numerous consumption of wild seeds than did juveniles. Plastic granules were also found in 3.8% of individuals.
Conclusion: A greater number of wild seed species was found in the diet in contrast to previous studies performed in farmland. Echium plantagineum and Amaranthus deflexus could be important seed sources for Turtle Doves in Mediterranean forest. Additionally, the herbaceous species found in the diet whose seeds ripen earlier in the season might play an important role in Turtle Dove reproductive performance, since they are frequently the only available food in the first half of the breeding season. 相似文献
Materials and methods: Forty-eight patients with NSCNP were randomly assigned to the neck group (NG) that observed neck images or the foot group (FG) that observed foot images. Response time, response accuracy, cervical ROM, and joint position error (JPE) were the main variables. The secondary outcome measures included psychosocial variables.
Results: Differences between groups in the cervical ROM for flexion (p?=?.043) were obtained, being NG group the one which obtained greater values. NG showed an improvement in right rotation (p?=?.018) and a decrease in flexion was found in the FG (p?=?.039). In JPE, differences between groups were obtained in the left rotation (p?=?.021) and significant changes were found in the NG for flexion, extension, and left rotation movements (p?<?.05). Moderate associations were found between left and right accuracy regarding to post-intervention flexion and right rotation (r?=?0.46, r?=?0.41; p?<?.05) in NG.
Conclusion: Improvements in cervical range of motion and joint position sense are obtained after the performance of the laterality discrimination task of images of the neck but not the feet. Visualization of images of the painful region presents moderate correlations with the accuracy and response time in the movements of flexion and right rotation. 相似文献
Areas covered: This review describes the identification of Wisteria floribunda agglutinin (WFA) as a probe that recognizes the altered glycan structure of glycoproteins secreted by diseased cells. WFA may be employed as a probe for several diseases, e.g., liver fibrosis, liver cirrhosis, prostate cancer, ovarian cancer, and IgA nephropathy. The advantage of employing WFA as a serum biomarker probe is that only very small amounts of WFA-positive glycoproteins are present in serum; therefore, WFA background in serum is very low.
Expert commentary: Based on the findings to date, several WFA-positive serum biomarkers may be measured without pre-purification of target glycoproteins, indicating their utility as serum biomarkers in patients with various diseases. 相似文献
Areas covered: This review is a summary of literature searches from PubMed, NASA, Roskosmos and the authors’ research experiences and opinions. The review covers the available proteomic data on the effects of spaceflight factors on the human body, including both real space missions and ground-based model experiments.
Expert commentary: Overall, the authors believe that the present background, methodology and equipment improvements will enhance spaceflight safety and support accumulation of new knowledge on how organisms adapt to extreme conditions. 相似文献
Aims: To test resource allocation hypotheses analysing the relationship between parental and offspring nutritional condition.
Methods: We measured blood chemistry parameters related with nutritional condition in 24 parents and their nestlings in a colony of Black-browed Albatrosses.
Results: There were no significant differences in blood parameters between sexes or location of the nest within the colony, neither among adults nor among nestlings. We found a significant positive correlation between parents and the nutritional condition of their offspring, measured as urea, uric acid and beta-hydroxybutyrate concentrations in blood.
Discussion: These relationships demonstrate that condition of the young seems to be merely a reflection of parental condition. An interesting relationship between alkaline phosphatase concentration in adults and nutritional condition of their nestlings was found, suggesting that age of the parents would be a key factor explaining quality of the nestling. 相似文献
Shoulder flexion and abduction movements of 11 healthy volunteers were recorded using a standard motion capture system (Vicon, Oxford Metrics Ltd, Oxford, UK), then GH kinematic and kinetic parameters were computed. The true position of the GH rotation centre was determined using a low dose x-ray scanner (EOS? imaging, France) and this position was transferred to the motion data. GH angles and moments were re-computed for each position of the GH rotation centre after errors of up to ± 20?mm were added in increments of ± 5?mm to each axis. The three-dimensional error range was 5?mm to 34.65?mm.
GH joint angle and moment values were significantly altered from 10?mm of three-dimensional error, and from 5?mm of error on individual axes. However, errors on the longitudinal and antero-posterior axes only caused very small alterations of GH joint angle and moment values respectively. Future research should develop methods of GH rotation centre estimation that produce three-dimensional location errors of less than 10?mm to reduce error propagation on GH kinematics and kinetics. 相似文献
In our study, we investigated in vivo and in vitro possible pathogenic events relevant to BiPN using a well-established rat model, with particular reference to the extent of proteasome inhibition and the effects on α-tubulin polymerization in sciatic nerves and dorsal root ganglia specimens obtained from animals treated with chronic regimens at a dose of 0.2 mg/kg intravenously. The same assessments were also performed after a single injection. Moreover, these studies were replicated in vitro using embryonic DRG neurons exposed to 100 nM BTZ and adult DRG neurons exposed to 10–50 nM BTZ for 24 h and 48 h.
A significant increase in the polymerized fraction of α-tubulin and prolonged proteasome inhibition were observed after the chronic BTZ treatment in vivo. Recovery to physiological levels was observed after a 4-week follow-up post-treatment period. Proteasome inhibition and increased α-tubulin polymerization were also observed following BTZ treatment of both embryonic and adult DRG neurons in vitro.
Our in vivo results suggest that proteasome inhibition and alteration of tubulin dynamics contribute to BiPN. The in vitro systems here described reliably replicate the in vivo results, and might therefore be used for further mechanistic studies on the effects of proteasome inhibitors on neurons. 相似文献
http://zoobank.org/urn:lsid:zoobank.org:pub:EC3284BA-C07F-48AC-8AF5-4F9D2EF4EA6C 相似文献
Methods. DNA sequences were extracted from recently collected material at two locations and compared with those for species in a published phylogeny of the genus to establish the position of C. morganii. Photographic images were obtained of key features of the species for the preparation of illustrations for publication.
Key results. Cheilolejeunea morganii does not match any species described for New Zealand or Australia. The sequencing results indicate its position in the phylogeny is close to Section Paroicae. A key to the New Zealand species of Cheilolejeunea is provided.
Conclusions. In the Australasian flora, C. morganii is distinguished from other species by its combination of monoicy, pycnolejeuneoid gynoecial innovations, lobule length less than 50% lobe length and a multicellular second lobule tooth with 3–4 cells uniseriate. A case is presented for the recognition of the species as a New Zealand endemic. 相似文献
Family Xulsigiidae is registered in Zoobank under the http://www.zoobank.org/urn:lsid:zoobank.org:act:3A57B428-638A-439A-AEC4-D18B5959B5CA
Genus Xulsigia is registered in Zoobank under the http://www.zoobank.org/urn:lsid:zoobank.org:act:2B255A30-5A7C-4CF8-AE77-18ED6E8E03C2 相似文献
Objective: The aim of this study was to examine the association of CD40 polymorphisms (-1?C>T (rs1883832) and 945G>T (rs4810485)) and myocardial infarction (MI), and to test the association of CD40 gene haplotypes with MI in Tunisians.
Materials and methods: Three hundred and fifty MI patients and 301 apparently healthy controls were included in the study. The polymorphisms of CD40 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).
Results: There were significant differences in the genotype and allele frequencies of CD40 gene -1?C>T (rs1883832) polymorphism between cases and controls. Stratifying according to gender, the association between the TT genotype and MI was statistically significant in males, only. Haplotype analysis revealed that the C-T and T-G haplotypes were associated with an increased risk of MI (p?=?0.012 and p?<?0.001, respectively).
Conclusions: Our work showed a significant association between the -1?C>T (rs1883832) polymorphism of the CD40 gene and MI in the Tunisians. 相似文献
A large variety of plant parts can be heat treated: Whole tree, scions, vitroplants, seedlings, stalks, cuttings, sprouts, cut flowers, seeds, bulbs, tubers, corms, or fruit and vegetables in storage. The target pathogenic microorganisms are mainly fungi, viruses, and bacteria. Many studies show the success of reducing diseases by heat. Thermotherapy also is the main means, associated with meristem and tip culture, of producing virus-free explants from infected mother-plants.
Most bacterial diseases of annual plants are seed-borne. Seed-transmission provides numerous foci of primary infection in the field and only a relatively small amount of infested seeds is sufficient to promote serious disease outbreaks. To disinfect seeds, authors mainly use hot water and hot air treatments. Satisfactory control has been obtained for several bacterial diseases (on tomato, tobacco, rice, barley, cucumber, Crucifers, pumpkin, guar, and cotton), mostly caused by the genera Xanthomonas and Pseudomonas. Thermotherapy is more difficult to use with large seeds of legumes, such as pea, bean, or soybean, because a significant decrease of germination is often obtained before the bacteria have been totally killed. The success of thermotherapy may be improved by combination with chemicals at the seed stage, by sprays during plant growth, or by replacing water with nonaqueous fluids.
When no efficient chemicals are known to control a disease, treating seeds by heat may be of great interest. However, the method requires studies to determine the most appropriate kind of heat for a particular plant part, and the optimal combination of time and temperature of exposure to use for the best efficiency with the least damage to the host. 相似文献