Ottoman scientific literature during the 18th and 19th centuries

Istambul, 1996年10月7日-11

Altın için cu(ıı) kullanılarak oksidatif kenetlenmeye dayayan spetrofotometrik bir tayin yönteminin geliştirilmesi

In this study, m- and p-phenylenediamine’s reactions which were in the presence of Cu(II) and Au(III) ions were investigated using spectrophotometric and potentiometric method. The results of the reactions between Cu(II) and Au(III) and m- and pphenylenediamine mixtures it was found out that, there is an oxidation by means of complexation. And as a result of oxidation, a diazo compound occured from amines and Cu(II) were reduced to elementel form, Au(III) was reduced to Au(I). Also the formation conditions of the reactions of these metals with amines were investigated, the pH range that the reactions takes place, time needed for the formation of the reactions and the mol ratios needed for the complete reaction of the metals with amines. Mole ratios are calculated as: Cu(II) / (m+p)phenylenediamine = 1 / 2; Au(III) / (m+p)phenylenediamine = 1/2 As a result of these spectrophotometric and potentiometric experiments, the basis of a new and easy determination method for Au(III) brought up.Bu çalışmada m- ve p-fenilendiaminlerin Cu(II) ve Au(III) ile verdiği reaksiyonlar spektrofotometrik ve potansiyometrik olarak incelenerek bir tayin yönteminin geliştirilmesi amaçlanmıştır. m- ve p-fenilendiamin karışımları ile Cu(II) ve Au(III)’ün verdiği reaksiyonlar sonucunda kompleksleşme üzerinden giden bir oksidasyon olduğu, bu oksidasyon sonucunda aminler arasında bir diazo bileşiği oluşurken Cu(II)’nin elementel hale Au(III) ün ise Au(I) basamağına indirgendiği görülmüştür. Ayrıca Cu(II) ile aminlerin verdikleri reaksiyonların oluşum koşulları incelenerek, reaksiyonun meydana geldiği pH aralığı, reaksiyonların oluşum süreleri ve bu metallerle aminlerin tam olarak reaksiyona girebilmesi için gerekli olan mol oranları bulunmuştur. Deneylerden elde edilen sonuçlardan Cu(II) ve Au(III)’ün aminlerle oluşturdukları oksidatif bağlanma ürünlerinin mol oranları; Cu(II)/(m+p)fenilendiamin = 1 / 2 ; Au(III) / (m+p)fenilendiamin= 1 / 2 olarak bulunmuştur. Spektrofotometrik ve potansiyometrik olarak yapılan bu deneyler sonucunda yeni basit bir spektrofotometrik tayin yönteminin temelleri ortaya konmuştur

Perception of social interaction compresses subjective duration in an oxytocin-dependent manner

Communication through body gestures permeates our daily life. Efficient perception of the message therein reflects one's social cognitive competency. Here we report that such competency is manifested temporally as shortened subjective duration of social interactions: motion sequences showing agents acting communicatively are perceived to be significantly shorter in duration as compared with those acting noncommunicatively. The strength of this effect is negatively correlated with one's autistic-like tendency. Critically, intranasal oxytocin administration restores the temporal compression effect in socially less proficient individuals, whereas the administration of atosiban, a competitive antagonist of oxytocin, diminishes the effect in socially proficient individuals. These findings indicate that perceived time, rather than being a faithful representation of physical time, is highly idiosyncratic and ingrained with one's personality trait. Moreover, they suggest that oxytocin is involved in mediating time perception of social interaction, further supporting the role of oxytocin in human social cognition

Homeodomain protein Otp affects developmental neuropeptide switching in oxytocin neurons associated with a long-term effect on social behavior

No supplementary materials.Proper response to stress and social stimuli depends on orchestrated development of hypothalamic neuronal circuits. Here we address the effects of the developmental transcription factor orthopedia (Otp) on hypothalamic development and function. We show that developmental mutations in the zebrafish paralogous gene otpa but not otpb affect both stress response and social preference. These behavioral phenotypes were associated with developmental alterations in oxytocinergic (OXT) neurons. Thus, otpa and otpb differentially regulate neuropeptide switching in a newly identified subset of OXT neurons that co-express the corticotropin-releasing hormone (CRH). Single-cell analysis revealed that these neurons project mostly to the hindbrain and spinal cord. Ablation of this neuronal subset specifically reduced adult social preference without affecting stress behavior, thereby uncoupling the contribution of a specific OXT cluster to social behavior from the general otpa(-/-) deficits. Our findings reveal a new role for Otp in controlling developmental neuropeptide balance in a discrete OXT circuit whose disrupted development affects social behavior.Israel Science Foundation grants: (1511/16, 957/12, 2137/16).info:eu-repo/semantics/publishedVersio

Loss of Arc renders the visual cortex impervious to the effects of sensory experience or deprivation

A myriad of mechanisms have been suggested to account for the full richness of visual cortical plasticity. We found that visual cortex lacking Arc is impervious to the effects of deprivation or experience. Using intrinsic signal imaging and chronic visually evoked potential recordings, we found that Arc−/− mice did not exhibit depression of deprived-eye responses or a shift in ocular dominance after brief monocular deprivation. Extended deprivation also failed to elicit a shift in ocular dominance or open-eye potentiation. Moreover, Arc−/− mice lacked stimulus-selective response potentiation. Although Arc−/− mice exhibited normal visual acuity, baseline ocular dominance was abnormal and resembled that observed after dark-rearing. These data suggest that Arc is required for the experience-dependent processes that normally establish and modify synaptic connections in visual cortex.Howard Hughes Medical InstituteNational Science Foundation (U.S.