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151.
Presenting joint kinematics of human locomotion using phase plane portraits and Poincaré maps 总被引:1,自引:0,他引:1
Additional graphical tools are needed to better visualize the joint kinematics of human locomotion. Standard plots in which the joint displacements are plotted against time or percent gait cycle do not provide sufficient information about the dynamics of the system. In this article, a study based on the two graphical tools of nonlinear dynamics to visualize the steady-state kinematics of human gait is presented. An experimental setup was developed to acquire the necessary data for application of the techniques. Twenty young adults, whose medical histories are free of gait pathology, were tested. Computerized electrogoniometers and foot switches were used to measure the kinematic data of the lower extremities and capture four instants of the gait cycle: heel strike, foot flat, heel off, and toe off. Phase plane portraits of each joint were constructed for the sagittal plane by plotting angular velocity against angular displacement. Poincaré maps were obtained by periodically sampling the joint profiles at toe off and plotting the ith iterate against the (i + 1)th one. Phase plane portraits are useful in monitoring the variations of joint velocity and position on the same graph in a more compact form. Poincaré maps are effective in differentiating steady gait from transient locomotion. 相似文献
152.
In the last decade, risk-based remediation following a framework similar to risk-based correction action (RBCA) has gained acceptance across the country and generic/Tier 1 Risk-Based Action Limits (RBALs) for hundreds of chemicals have been tabulated. However, there have been only a few studies that focused on understanding the causes of discrepancy among cleanup standards and policies of the hazardous waste programs among the states. This study aims to fill this critical need by examining the basis of generic (i.e., Tier 1) residential RBALs developed by the states, which are within the regulatory domain of U.S. Environmental Protection Agency's Region 5. Specifically, we seek to investigate the approaches/methodologies and the policy/technical rationale used in establishing RBALs, along with degree of inconsistency, and the causes and implications of inconsistencies. In addition, we developed RBALs for a case study site using both deterministic and probabilistic risk assessment approaches and compared these against RBALs developed by the states to infer about public health-protectiveness of the state-specific RBALs. We found three- and four-order-of magnitude difference among state RBALs for PAHs and VOCs, respectively. The degree of clean up deemed appropriate under Tier 1 evaluation by the midwestern states significantly differ from one another, which has both public health and economic implications. 相似文献
153.
Dayane Priscilla de Souza Queiroz Carlos Alexandre Carollo M?nica Cristina Toffoli Kadri Yasmin Silva Rizk Vanessa Carneiro Pereira de Araujo Paulo Eduardo de Oliveira Monteiro Patrik Oening Rodrigues Elisa Teruya Oshiro Maria de Fátima Cepa Matos Carla Cardozo Pinto de Arruda 《Memórias do Instituto Oswaldo Cruz》2016,111(3):147-154
The polar hydroethanolic extract from Selaginella sellowii(SSPHE)
has been previously proven active on intracellular amastigotes (in vitro test) and
now was tested on hamsters infected with Leishmania (Leishmania)
amazonensis (in vivo test). SSPHE suppressed a 100% of the parasite load
in the infection site and draining lymph nodes at an intralesional dose of 50
mg/kg/day × 5, which was similar to the results observed in hamsters treated with
N-methylglucamine antimonate (Sb) (28 mg/Kg/day × 5). When orally
administered, SSPHE (50 mg/kg/day × 20) suppressed 99.2% of the parasite load in
infected footpads, while Sb suppressed 98.5%. SSPHE also enhanced the release of
nitric oxide through the intralesional route in comparison to Sb. The chemical
fingerprint of SSPHE by high-performance liquid chromatography with diode-array
detection and tandem mass spectrometry showed the presence of biflavonoids and high
molecular weight phenylpropanoid glycosides. These compounds may have a synergistic
action in vivo. Histopathological study revealed that the intralesional treatment
with SSPHE induced an intense inflammatory infiltrate, composed mainly of mononuclear
cells. The present findings reinforce the potential of this natural product as a
source of future drug candidates for American cutaneous leishmaniasis. 相似文献
154.
The molecular organization of the beta-globin complex of the deer mouse, Peromyscus maniculatus 总被引:1,自引:0,他引:1
Padgett RW; Loeb DD; Snyder LR; Edgell MH; Hutchison CA d 《Molecular biology and evolution》1987,4(1):30-45
Recombinant DNA clones have been isolated that contain 80 kb of the
beta-globin complex from the deer mouse, Peromyscus maniculatus.
Comparisons of this complex with that from the laboratory mouse, Mus
domesticus (with an order 5'-Hbby, Hbb-bhO, Hbb-bhl, Hbb-bh2, Hbb-bh3,
Hbb-bl, Hbb-b2 3') highlight organizational trends in the beta-globin
complex since the two species diverged. Unlike other mammals studied thus
far, the deer mouse possesses three adult genes. Partial sequence analysis
indicates that each of the three adult genes is intact and hence may be
functional. Hybridization of one of the two Mus pseudogenes, Hbb-bh3, to
genomic blots from Peromyscus reveals that it has a homologous counterpart
in Peromyscus. Homologous genes to the two gamma-like Mus genes, Hbb-bhO
and Hbb-bhl, are also found in Peromyscus. The strong hybridization between
the Hbb-bhl genes and significant nucleotide similarity between the Hbb-bhO
genes suggest that both pairs are important for the ontogeny of these mice
although no known product has been identified for the Hbb-bhO genes. The
presence of Hbb-bhO and Hbb-bhl in Peromyscus suggests that the duplication
that created this related gene set occurred before the two lineages
diverged. A single gene for Hbb-y has been isolated from Peromyscus. The
adult region in Peromyscus has undergone significant divergence from the
same region in Mus, having three rather than two adult genes, the
acquisition of at least 15 kb of extra DNA relative to Mus, and possibly
the loss of the Hbb-bh2 pseudogene. The nonadult region of the complex, in
contrast, contains the same set of genes apparently distributed over the
same amount of DNA as in the Mus beta- globin complex. This observation
suggests that the embryonic region of the complex is more evolutionarily
stable than the adult region.
相似文献
155.
156.
R Lopez de Onate S Giammanco F Carollo M Ernandes M A Paderni 《Bollettino della Società italiana di biologia sperimentale》1989,65(3):227-233
The aim of this research is to study the effects of a diet almost devoid of tryptophan, which is given by a feeding with precooked yellow corn meal (corn mush), on the alterations of the estrous cycle of animals in several conditions of environmental lighting. Indeed, it is known that cerebral serotonin influences the releasing of LH and consequently the ovulation. The different types of environmental lighting are: 1) Natural (alternating Day-Night = L/D). 2) Continuous dark (D/D). 3) Continuous light by sodium steams (L/L sodium). 4) Continuous light by fluorescent neon tubes (L/L neon). The muricide behaviour is studied by comparison rat-mouse. The feeding with precooked yellow corn meal (diet lacking of tryptophan) unchains in the 100% of the observations the CEA (Constant Estrous Anovulatory), and significantly shrinks the estral cycle in the female Wistar Rat in several conditions of environmental lighting. 相似文献