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61.
Miriam Jennifer Sima Theresa Matzinger Thomas Bugnyar Simone Pika 《Ethology : formerly Zeitschrift fur Tierpsychologie》2018,124(1):33-44
Conflicts are costly because they can damage social relationships. To buffer conflicts, various species use post‐conflict behaviour, such as reconciliation or third‐party affiliation. Both behaviours have predominantly been studied in non‐human primates. However, recently, studies revealed post‐conflict behaviour in other mammalian and some bird species (e.g., corvids). While third‐party affiliation has been reported in several corvid species, reconciliation has only rarely been observed. The social structure of the studied groups has been postulated as a reason for the absence of reconciliation. Here, we investigated whether post‐conflict behaviours in corvids indeed mirror the relationship structure. We studied the behaviour of a newly established group of juvenile carrion crows (Corvus corone corone), where pair bonds had not yet been established. We applied a combination of observations and food monopolisation experiments to quantify the use of post‐conflict behaviours. Provisioning food in one or two pieces induced different patterns of aggression during feeding and differently affected the affiliation patterns after feeding. Specifically, victims of severe aggression affiliated with third parties after conflicts in the two‐piece condition, while aggressors affiliated with victims of mild aggression in the one‐piece condition. We thus provide the first evidence that a corvid species, crows, flexibly engage in both third‐party affiliation and reconciliation. 相似文献
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64.
Naser Zanganeh Ehsan Siahpoushi Nejat Kheiripour Sima Kazemi Mohammad Taghi Goodarzi Mohammad Yousef Alikhani 《Biological trace element research》2018,182(2):204-208
Brucellosis is regarded as one of the most common diseases among humans and livestock. In the present study, we aimed to assess the effect of this disease on the level of various cations including copper (Cu), manganese (Mn), zinc (Zn), and magnesium (Mg) as well as oxidative stress status in the serum of people suffering from brucellosis. The present case-study was carried out on 40 patients with brucellosis (case) and 20 healthy people (control). Blood specimens were taken from all the people and the level of essential trace elements and oxidative stress status were measured. The serum level of copper in the case group (165.39 ± 43.19 μg/dl) was significantly higher compared with that in the control group (122.12 ± 28.88 μg/dl). Whereas the serum level of zinc was significantly lower in the case group compared with that in the control group (76.47 ± 28.88 vs. 92.85 ± 23.16 μg/dl). The manganese and magnesium serum levels did not differ significantly between the two groups. Furthermore, total antioxidant capacity level was significantly lower in the case group (122.12 ± 28.22 μmol/ml) than that in the control group (3.08 ± 0.12 μmol/ml) and the level of serum malondialdehyde was significantly higher in the case group (7.20 ± 0.23 mmol/ml) than that in the control group (4.0 ± 0.19 mmol/ml). Brucellosis can cause alteration in the serum level of essential trace elements. Moreover, the present study indicated that brucellosis produces oxidative stress in patients. 相似文献
65.
Nazila Danesh Zahra Navaee Sedighi Sima Beigoli Atena Sharifi-Rad Mohammad Reza Saberi 《Journal of biomolecular structure & dynamics》2018,36(7):1747-1763
The interactions between estradiol and two carrier proteins, i.e. human serum albumin (HSA) and holo-transferrin (HTF) in aqueous solution at pH = 7.4 were studied by three-dimensional fluorescence emission spectroscopy, isothermal titration calorimetry (ITC), zeta-potential, resonance light-scattering and molecular modeling. Extensive fluorescence quenching was observed throughout the interaction between the drug and both proteins. Moreover, conformational changes were determined by observing the rearrangement of Trp residues during binding of estradiol with HSA and HTF at different concentrations. ITC experiments revealed that, in the presence of estradiol, both van der Waals forces and hydrogen bonding became predominant. In addition, other binding parameters such as enthalpy and entropy changes were determined by the zeta potential method. Molecular modeling suggested that estradiol was situated within sub-domain IB sited in the hydrophobic cluster in Site I, whereas the drug was located in the N-terminal of HTF where it was hydrogen bonded with Ala 670. 相似文献
66.
Telmatochromis temporalis is a biparental substrate breeding cichlid that mates in size-assortative monogamy at the southern end of Lake Tanganyika.
In this population, at least a few months before the rainy season, large males (90–110 mm TL) did not pair. However, they
maintained large territories that were defended against conspecific large males and that contained several pairing small males
(50–80 mm). Large males occasionally visited the nests of the small pairs in their territories, and selectively took over
the nests by attacking the owner male. During the takeover, the large males courted the small females in the nests and might
have ejaculated sperm. After the large males left the nests, the small owner males conducted paternal care at the nests. These
behaviour patterns of large males are similar to piracy mating reported in other polygamous fish species. The piracy mating
of large maleT. temporalis seems to be an alternative tactic when large females are not available. 相似文献
67.
Samane Naeeminejad Reza Assaran Darban Sima Beigoli Mohammad Reza Saberi 《Journal of biomolecular structure & dynamics》2017,35(15):3250-3267
The interaction between synthesized heterocyclic benzene sulfonamide compounds, N-(7-benzyl-56-biphenyl-2m-tolyl-7H-pyrrolo[23-d]pyrimidine–4–yl)-benzene sulfonamide (HBS1), N-(7-benzyl-56-biphenyl-2-m-tolyl-7H-pyrrolo[23-d] pyrimidine-4-yl)-4-methyl- benzene sulfonamide (HBS2), and N-(7-benzyl-56-biphenyl-2-m-tolyl-7H-pyrrolo[23-d]pyrimidine-4-yl)-4-chloro-benzene sulfonamide (HBS3) with Hb was studied by fluorescence quenching, zeta potentional, circular dichroism, and molecular modeling techniques. The fluorescence spectroscopy experiments were performed in order to study the conformational changes, possibly due to a discrete reorganization of Trp residues during binding between HBS derivatives and Hb. The variation of the KSV value suggested that hydrophobic and electrostatic interactions were the predominant intermolecular forces stabilizing the complex. The KSV1 ans KSV2 values of HBS derivatives with Hb are .6 × 1013 and 3 × 1013 M?1 for Hb–HBS1, 1 × 1013 and 4 × 1013 M?1 for Hb–HBS2, .9 × 1013, and 6 × 1013 M?1 for Hb–HBS3, respectively. The molecular distances between Hb and HBS derivatives in binary and ternary systems were estimated according to Förster’s theory of dipole–dipole non-radiation energy transfer. The quantitative analysis data of circular dichroism spectra demonstrated that the binding of the three HBS derivatives to Hb induced conformational changes in Hb. Changes in the zeta potential of the Hb–HBS derivatives complexes demonstrated a hydrophobic adsorption of the anionic ligand onto the surface of Hb as well as both electrostatic and hydrophobic adsorption in the case of the complex. The modeling data thus confirmed the experimental results. This study is expected to provide important insight into the interaction of Hb with three HBS derivatives to use in various toxicological and therapeutic processes. 相似文献
68.
Chen L Hainrichson M Bourdetsky D Mor A Yaron S Baasov T 《Bioorganic & medicinal chemistry》2008,16(19):8940-8951
A new pseudo-disaccharide NB23 with a 3',4'-methylidene protection was designed and its properties were evaluated in comparison to other two structurally related pseudo-disaccharides. The basicity of the 2'-amine was found to be well correlated to acute toxicity data in mice: the increase in the basicity is associated with the toxicity increase. Based on these data, a new pseudo-trisaccharide NB45 was constructed. NB45 exhibited significant antibacterial activity while at the same time retained low acute toxicity. 相似文献
69.
Environmental and social factors have important effects on aggressive behaviors. We examined the effect of reproductive experience on aggression in a biparental species of mouse, Peromyscus californicus. Estrogens are important in mediating aggressive behavior so we also examined estrogen receptor expression and c-fos for insights into possible mechanisms of regulation. Parental males were significantly more aggressive than virgin males, but no significant differences in estrogen receptor alpha or beta expression were detected. Patterns of c-fos following aggression tests suggested possible parallels with maternal aggression. Parental males had more c-fos positive cells in the medial amygdala, and medial preoptic area relative to virgin males. The medial preoptic area is generally considered to be relatively less important for male-male aggression in rodents, but is known to have increased activity in the context of maternal aggression. We also demonstrated through habituation-dishabituation tests that parental males show exaggerated investigation responses to chemical cues from a male intruder, suggesting that heightened sensory responses may contribute to increased parental aggression. These data suggest that, in biparental species, reproductive experience leads to the onset of paternal aggression that may be analogous to maternal aggression. 相似文献
70.
Sampath Amutha Krishnan Kathiravan Sima Singer Liana Jashi Ilan Shomer Benjamin Steinitz Victor Gaba 《In vitro cellular & developmental biology. Plant》2009,45(6):758-768
Regeneration of new shoots in plant tissue culture is often associated with appearance of abnormally shaped leaves. We used
the adventitious shoot regeneration response induced by decapitation (removal of all preformed shoot apical meristems, leaving
a single cotyledon) of greenhouse-grown cotyledon-stage seedlings to test the hypothesis that such abnormal leaf formation
is a normal regeneration progression following wounding and is not conditioned by tissue culture. To understand why shoot
regeneration starts with defective organogenesis, the regeneration response was characterized by morphology and scanning electron
and light microscopy in decapitated cotyledon-stage Cucurbita pepo seedlings. Several leaf primordia were observed to regenerate prior to differentiation of a de novo shoot apical meristem from dividing cells on the wound surface. Early regenerating primordia have a greatly distorted structure
with dramatically altered dorsoventrality. Aberrant leaf morphogenesis in C. pepo gradually disappears as leaves eventually originate from a de novo adventitious shoot apical meristem, recovering normal phyllotaxis. Similarly, following comparable decapitation of seedlings
from a number of families (Chenopodiaceae, Compositae, Convolvulaceae, Cucurbitaceae, Cruciferae, Fabaceae, Malvaceae, Papaveraceae,
and Solanaceae) of several dicotyledonous clades (Ranunculales, Caryophyllales, Asterids, and Rosids), stems are regenerated
bearing abnormal leaves; the normal leaf shape is gradually recovered. Some of the transient leaf developmental defects observed
are similar to responses to mutations in leaf shape or shoot apical meristem function. Many species temporarily express this
leaf development pathway, which is manifest in exceptional circumstances such as during recovery from excision of all preformed
shoot meristems of a seedling. 相似文献