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F Claro

Publications and source records attributed to F Claro.

At least 19 recordsLinked to original sources
PubMed2003

A terahertz molecular switch.

We present time-dependent results describing the current through a molecular device, modeled as a complex with two active centers connected to leads under bias. We show that, at a properly adjusted external voltage, a passing terahertz electromagnetic pulse may cause a transition between states of finite and negligible current, suggesting that the system might be useful as a nanoscopic switch in the terahertz range. A phase diagram defining the bias region in which the transition takes place within a short time is given. As described, the physical processes involved are of an entirely different nature than those in ordinary photodetectors.

Journal Article↗
PubMed2003

Identification by R-banding and FISH of chromosome arms involved in Robertsonian translocations in several deer species.

We constructed and analyzed the RBG-banded karyotype of five deer species: Chital (Axis axis), White-lipped deer (Cervus albirostris), Rusa deer (Cervus timorensis russa), Sambar deer (Cervus unicolor) and Eld's deer (Cervus eldi siamensis). Among these five species, only Eld's deer had been previously karyotyped using R-banding. In order to identify all the chromosome correspondences with cattle and precisely which chromosome arms are involved in Robertsonian translocations, we compared the karyotypes of these five species with those of the closely related and well-characterized species, cattle (Bos taurus) and Vietnamese Sika deer (Cervus nippon pseudaxis). Among these six deer species (the five above plus the Vietnamese Sika deer), we found thirteen different Robertsonian translocations involving nineteen different chromosome arms. Thirteen chromosome arms were identified by comparison of R-banding patterns only and the remaining six were either confirmed or identified by FISH-mapping of bovine or caprine probes previously localized in cattle. Finally, we observed that five of the thirteen Robertsonian translocations are shared by at least two species and that some chromosome arms are more frequently involved in Robertsonian translocations than others.

Animals↗
PubMed2002

Optical absorption for parallel cylinder arrays.

We study the long-wavelength electromagnetic resonances of interacting cylinder arrays. By using a normal-modes expansion where the effects of geometry and material are separated, it is shown that two parallel cylinders with different radii have electromagnetic modes distributed symmetrically about depolarization factor 1 / 2. Both sets couple to longitudinal and transverse components of the external field, but amplitudes of symmetric depolarization factors become exchanged when considering longitudinal or transverse polarization. We also find that amplitudes satisfy sum rules that depend on the ratio of the cylinders radii. The main effect of the difference in radii is a spectral shift towards the isolated cylinder resonance as this difference increases.

Journal Article↗
PubMed2001

Cytogenetic comparison between Vietnamese sika deer and cattle: R-banded karyotypes and FISH mapping.

R-banded chromosomes of Vietnamese sika (VS) deer (Cervus nippon pseudaxis, 2N = 66), a threatened subspecies of sika deer endemic to Vietnam, are presented for the first time and were compared with bovine R-banded chromosomes to define a standard karyotype. Nineteen VS deer autosomes (CNP) were identified on the basis of the banding pattern relative to bovine chromosomes (BTA), while hypotheses for the remaining thirteen were proposed from comparisons with the published deer genetic map, BTA 1, 2, 5, 6, 8 and 9 each equivalent to two separate acrocentric CNP chromosomes and BTA 26 and 28 associated in a tandem fusion. To confirm these hypotheses, probes for the twenty-nine Texas nomenclature type I markers specific for each cattle autosome, sixteen other type I and fourteen microsatellite markers were used in FISH experiments on VS deer chromosomes. CNP7 presented the most complex rearrangement as compared with cattle chromosomes. A complete correspondence between VS deer and cattle chromosomes was established and it was extended with a comparison with the human karyotype to transfer human map information to this species of scientific and economic interest. Moreover, this work anchors the deer genetic linkage map to chromosome-specific markers.

Animals↗
PubMed2000

Normal-mode theory for cylinder arrays

We study a set of interacting cylinders under the influence of an electromagnetic field in the long-wavelength limit. Cylindrical harmonics are used as basis functions in order to write the electric potential in terms of multipolar moments of the charge distribution in the cylinders. We get a normal-mode expansion where the effects of geometry and material are separated. It is shown that for a row of identical parallel cylinders the electromagnetic modes are distributed symmetrically about the depolarization factor 1/2, each set coupling to different components of the external field. The amplitudes of these symmetric depolarization factors are the same and satisfy proper sum rules.

Journal Article↗
PubMed1996

The karyotype of the addax and its comparison with karyotypes of other species of Hippotraginae antelopes.

The karyotype of the addax (Addax nasomaculatus, 2n = 58) has been investigated by RBG and CBG banding techniques. All chromosomes are acrocentric except the first pair of autosomes, which is submetacentric. The X chromosome is the largest acrocentric, and the Y chromosome is a medium sized acrocentric. According to the standard conventions used for cattle and goat, p- and q-arms of the pair of submetacentric autosomes correspond, respectively, to chromosomes # 27 # 1. The comparison of banding patterns of chromosomes in addax and four other species of the subfamily Hippotraginae reveals several common features and a high degree of homoeology with caprine and bovine karyotypes.

Animals↗
PubMed1996

[Infectious pathology of Canidae and Felidae in zoological parks].

The Canidae (36 species) and Felidae (34-37 species) are two families of carnivores represented by numerous exotic species in zoos or wildlife reserves. To some extent, the diseases of these species are similar to those of dogs and cats, and are therefore relatively well known. However, there are differences in sensitivity to infectious agents, treatments and vaccines. Canidae and Felidae may also act as carriers or even vectors of zoonoses, such as leptospirosis, rabies, salmonellosis, toxoplasmosis and tuberculosis. Due to their behaviour patterns and morphological adaptations, these species are capable of transmitting various opportunistic infections by biting or scratching. These characteristics mean that Canidae and Felidae are difficult to keep in captivity, and require special health precautions, particularly protection from contact with stray carnivores.

Animals↗
PubMed1995

Lesions in the medial posterior region of the BST impair sexual behavior in sexually experienced and inexperienced male rats.

Previous studies have showed that lesions in the bed nucleus of the stria terminalis of experienced male rats impair some parameters of sexual behavior. The aim of this study was to examine the contribution of the medial posterior region of the bed nucleus of the stria terminalis (BSTMP), a sexually dimorphic region of this nucleus that pertains to the vomeronasal system, to the modulation of sexual behavior of the male rat. Small electrolytic bilateral lesions in the BSTMP were made in male heterosexual experienced and inexperienced rats. Sham lesioned animals were also tested as a control of the effects of the general surgical procedures. Behavioral tests were then performed to obtain standard measures of masculine sexual behavior. Our results indicate that the sexually experienced male rats with lesioned BSTMPs showed increases in the number of mounts and the number of intromissions and, consequently, in ejaculation latency. In contrast, the sexually naive male rats showed increases in first mount and intromission latencies and in ejaculation latency, but the latter occurred due to increases in the interintromission intervals. This group also showed low correlations between olfactory investigation of the anogenital area of the female and initiation and maintenance of copulatory behavior. The results suggest that sexual experience obtained in the very artificial conditions of laboratory tests could supply some of the cues provided by the BSTMP in the process of sensorial integration, which we hypothesize modulates the initiation and pacing of copulation. However, sexual experience does not apparently supply any other kinds of cues provided or processed in the BSTMP that are involved in modulating the elicitation of intromissions and ejaculations.

Animals↗
PubMed1995

Identification of p and q arms of the blesbok (Damaliscus dorcas phillipsi, Alcelaphinae) RBG-banded chromosomes with comparison to other wild and domestic bovids.

The RBG banded karyotype (2n = 38) of the blesbok (Damaliscus dorcas phillipsi) comprises 8 pairs of metacentric, 3 pairs of submetacentric and 7 pairs of acrocentric autosomes. The X and Y chromosomes are acrocentric. The 11 pairs of biarmed chromosomes correspond to Robertsonian translocations involving the chromosomes equivalent to goat and cattle chromosomes: 1;10, 4;5, 8;17, 7;9, 6;14, 13;15, 12;16, 20;22, 3;19, 2;27 and 11;23. The comparison of Blesbok karyotype with that of other species of Alcelaphinae and Hippotraginae reveals a high level of homoeology.

Animals↗
PubMed1994

MBR: a computer program to record and analyze parental behavior in rodents.

The Maternal Behavior Recorder (MBR) is a microcomputer program designed to record and analyze data from research on parental behavior of rats and other rodents. It is used to record the specific, characteristic patterns of maternal care in rodents: nest building, grooming, licking, crouching, and retrieval of pups. Moreover, it analyzes these events in terms of frequency and duration, allowing any events erroneously recorded to be corrected. The MBR can also simultaneously control observations made by one or two experimenters, and it calculates a set of reliability measures between them.

Animals↗
PubMed1994

The C-, G-, and R-banded karyotype of the scimitar-horned oryx (Oryx dammah).

Karyotypes of five males and one female scimitar-horned oryx (Oryx dammah) were prepared using lymphocyte and skin cells. CBG-, GTG-, and RBG-banded chromosomes were analysed and the banding patterns were compared with those of cattle, revealing a high level of homoeology except for chromosomes 9, 14, 21, Y, and X. Standard karyotypes are proposed for the scimitar-horned oryx karyotype, which contains 58 chromosomes with one pair of large submetacentric autosomes and 27 acrocentric autosomal pairs. The X and Y chromosomes are the largest and smallest acrocentrics. The scimitar-horned oryx chromosome 1 is submetacentric and appears to result from the fusion between ancestral forms of bovid chromosomes numbered 1 and 29 according to the READING CONFERENCE (1980) nomenclature and to ISCNDA 89 if GTG-banding is used.

Animals↗