345 research outputs found
PROGRESS OF HABITUATION OF WESTERN LOWLAND GORILLAS AND THEIR REACTION TO OBSERVERS IN MOUKALABA-DOUDOU NATIONAL PARK, GABON
We have conducted habituation of western lowland gorillas since May 2003 during a long-term socio-ecological survey on primates in Moukalaba-Doudou National Park (Moukalaba N.P.) in Gabon. After a training program to increase the skills of trackers to search for gorillas in tropical forest, we identifi ed one group named ‘Group Gentil' (GG). Since October 2005, we have focused our efforts on habituating this group and carrying out all-day follows that have resulted in the identifi cation of most adult and subadult individuals in GG. Here, we describe the habituation process of GG and the major problems we faced in habituation. First, we had to employ inexperienced trackers and modify our methods according to the gorillas' responses. Subsequently we continued to employ the same trackers and formed two teams consisting of researchers and trackers to search for gorillas on a daily basis. The skills of our trackers in performing constant and reliable follows of GG have gradually increased. Furthermore, our persistent follows seemed to have a less disruptive effect on their ranging patterns. Once all-day follows were achieved, GG came to tolerate our presence. Juveniles approached us with curiosity when the silverback male remained nearby. Males were habituated more quickly than females, as observed in other habitats. However, distinct differences were found in the responses to human observers between the silverbacks and females. Unlike mountain gorillas and eastern lowland gorillas, female western gorillas at Moukalaba showed aggressive responses to our approaches and occasionally attacked us with threatening vocalizations. Such female aggressiveness resembled that observed at Mondika in the process of habituation. However, while the silverback male usually ignored female aggression at Mondika, the silverback frequently rushed onto aggressive females to stop them at Moukalaba. Based on these similarities and differences in the habituation process at Moukalaba, we propose recommendations for achieving successful habituation
Radar-Based Estimation of Human Body Orientation Using Respiratory Features and Hierarchical Regression Model
This study proposes an accurate method to estimate human body orientation
using a millimeter-wave radar system. Body displacement is measured from the
phase of the radar echo, which is analyzed to obtain features associated with
the fundamental and higher-order harmonic components of the quasi-periodic
respiratory motion. These features are used in body-orientation estimation
invoking a novel hierarchical regression model in which a logistic regression
model is adopted in the first step to determine whether the target person is
facing forwards or backwards; a pair of ridge regression models are employed in
the second step to estimate body-orientation angle. To evaluate the performance
of the proposed method, respiratory motions of five participants were recorded
using three millimeter-wave radar systems; cross-validation was also performed.
The average error in estimating body orientation angle was 38.3 and
23.1 using respectively a conventional method with only the fundamental
frequency component and our proposed method, indicating an improvement in
accuracy by factor 1.7 when using the proposed method. In addition, the
coefficient of correlation between the actual and estimated body-orientation
angles using the conventional and proposed methods are 0.74 and 0.91,
respectively. These results show that by combining the characteristic features
of the fundamental and higher-order harmonics from the respiratory motion, the
proposed method offers better accuracy.Comment: 5 pages, 4 figures. This work is going to be submitted to the IEEE
for possible publicatio
Embryonic Development of the Pacific Lamprey, Entosphenus tridentatus
Embryonic development of the Pacific lamprey, Entosphenus tridentatus, from Japan is described. Egg sizes averaged 1.249 mm (longest axis) and 1.145 mm (shortest axis), the time required for hatching being 11 days at 18℃, shorter than previously reported for a lower water temperature (19 days at 15℃). Early development in E. tridentatus proceeded at a similar rate to that in other lampreys, in spite of different rearing water temperatures for the latter, indicating possible specific differences in basic developmental rates
Radar-Based Estimation of Human Body Orientation Using Respiratory Features and Hierarchical Regression Model
This letter proposes an accurate method to estimate human body orientation using a millimeter-wave radar system. Body displacement is measured from the phase of the radar echo, which is analyzed to obtain features associated with the fundamental and higher order harmonic components of the quasi-periodic respiratory motion. These features are used in body orientation estimation invoking a novel hierarchical regression model in which a logistic regression model is adopted in the first step to determine whether the target person is facing forward or backward; a pair of ridge regression models is employed in the second step to estimate body orientation angle. To evaluate the performance of the proposed method, respiratory motions of five participants were recorded using three millimeter-wave radar systems; cross validation was also performed. The average error in estimating body orientation angle was 38.3 ∘ and 23.1 ∘ using, respectively, a conventional method with only the fundamental frequency component and our proposed method, indicating an improvement in accuracy by a factor of 1.7 when using the proposed method. In addition, the coefficients of correlation between the actual and estimated body orientation angles using the conventional and proposed methods are 0.74 and 0.91, respectively. These results show that by combining the characteristic features of the fundamental and higher order harmonics from the respiratory motion, the proposed method offers better accuracy
Involvement of Nitric Oxide in a Rat Model of Carrageenin-Induced Pleurisy
Some evidence indicates that nitric oxide (NO) contributes to inflammation, while other evidence supports the opposite conclusion. To clarify the role of NO in inflammation, we studied carrageenin-induced pleurisy in rats treated with an NO donor (NOC-18), a substrate for NO formation (L-arginine), and/or an NO synthase inhibitor (S-(2-aminoethyl) isothiourea or NG-nitro-L-arginine). We assessed inflammatory cell migration, nitrite/nitrate values, lipid peroxidation and pro-inflammatory mediators. NOC-18 and L-arginine reduced the migration of inflammatory cells and edema, lowered oxidative stress, and normalized antioxidant enzyme activities. NO synthase inhibitors increased the exudate formation and inflammatory cell number, contributed to oxidative stress, induced an oxidant/antioxidant imbalance by maintaining high O2−, and enhanced the production of pro-inflammatory mediators. L-arginine and NOC-18 reversed the proinflammatory effects of NO synthase inhibitors, perhaps by reducing the expression of adhesion molecules on endothelial cells. Thus, our results indicate that NO is involved in blunting—not enhancing—the inflammatory response
Efficacy and tolerability of topiramate-augmentation therapy for schizophrenia: a systematic review and meta-analysis of randomized controlled trials
Demonstration of unconditional one-way quantum computations for continuous variables
Quantum computing promises to exploit the laws of quantum mechanics for
processing information in ways fundamentally different from today's classical
computers, leading to unprecedented efficiency. One-way quantum computation,
sometimes referred to as the cluster model of quantum computation, is a very
promising approach to fulfil the capabilities of quantum information
processing. The cluster model is realizable through measurements on a highly
entangled cluster state with no need for controlled unitary evolutions. Here we
demonstrate unconditional one-way quantum computation experiments for
continuous variables using a linear cluster state of four entangled optical
modes. We implement an important set of quantum operations, linear
transformations, in the optical phase space through one-way computation. Though
not sufficient, these are necessary for universal quantum computation over
continuous variables, and in our scheme, in principle, any such linear
transformation can be unconditionally and deterministically applied to
arbitrary single-mode quantum states.Comment: 9 pages, 3 figure
Evaluation of Streamwise Waveform on a High-Speed Water Jet by Detecting Trajectories of Two Refracted Laser Beams
Free surface fluctuations on a high-speed water jet were measured by a laser beam refraction technique. This method can be used to obtain quantitative time-series data on local surface fluctuations. The developed system employs two pulsed laser diodes, and it uses a high-speed optical sensor to detect the instantaneous positions of the laser beams that are refracted at the free surface. Fluctuations in the slope angle are measured at two locations separated by 1.27 mm. The wave speed of each free surface wave, which is determined by the zero-upcrossing method, is experimentally evaluated by the cross-correlation method. A two-dimensional waveform is obtained by integrating the slope angle data. The local mean wavelength and mean wave steepness are evaluated for average jet velocities up to =10 m/s. Streamwise waveforms of the high-speed water jet at several locations exhibit appreciable asymmetry and have steep profiles
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