Behavioral and Emotional Dynamics of Two People Struggling to Reach Consensus about a Topic on Which They Disagree

We studied the behavioral and emotional dynamics displayed by two people trying to resolve a conflict. 59 groups of two people were asked to talk for 20 minutes to try to reach a consensus about a topic on which they disagreed. The topics were abortion, affirmative action, death penalty, and euthanasia. Behavior data were determined from audio recordings where each second of the conversation was assessed as proself, neutral, or prosocial. We determined the probability density function of the durations of time spent in each behavioral state. These durations were well fit by a stretched exponential distribution, with an exponent, , of approximately 0.3. This indicates that the switching between behavioral states is not a random Markov process, but one where the probability to switch behavioral states decreases with the time already spent in that behavioral state. The degree of this “memory” was stronger in those groups who did not reach a consensus and where the conflict grew more destructive than in those that did. Emotion data were measured by having each person listen to the audio recording and moving a computer mouse to recall their negative or positive emotional valence at each moment in the conversation. We used the Hurst rescaled range analysis and power spectrum to determine the correlations in the fluctuations of the emotional valence. The emotional valence was well described by a random walk whose increments were uncorrelated. Thus, the behavior data demonstrated a “memory” of the duration already spent in a behavioral state while the emotion data fluctuated as a random walk whose steps did not have a “memory” of previous steps. This work demonstrates that statistical analysis, more commonly used to analyze physical phenomena, can also shed interesting light on the dynamics of processes in social psychology and conflict management.     

The effect of manganese-induced hypercholesterolemia on learning in rats

Since the exact mechanism of manganese (Mn)-induced learning disability is not known, we investigated the role of elevated cholesterol in rats exposed daily to 357 and 714 μg Mn/kg for 30 d. Significant Mn accumulation was accompanied by increased cholesterol content in the hippocampal region of Mn-treated rats. The learning, which is based on the time needed to reach food placed at the exit of a T-maze after a 1-d training period, was significantly slower in exposed rats than in unexposed rats. The rats receiving 357 and 714 μg Mn/kg reached the food in 104.5±13.8 and 113.3±25.7 s, respectively, on d 30, whereas their untreated counterparts reached the food in 28.7±11.4 s. This delay was completely corrected to 29.3±7.8 and 30.7±6.0 s in rats with coadministration of an inhibitor of cholesterol biosynthesis with 357 and 714 μg/kg of Mn. The correction of impaired learning was associated with the normalization of hippocampal cholesterol, but the Mn level in this region of the brain was not influenced in rats treated with a drug that inhibits cholesterol biosynthesis. These results suggested that Mn-induced hypercholesterolemia is involved in Mn-dependent learning disability.     

The protective effect of arbutin against potassium bromate-induced oxidative damage in the rat brain

This study aimed to investigate the protective effects of arbutin (ARB) against brain injury induced in rats with potassium bromate (KBrO₃). The rats were divided into four groups as Group 1: Control (0.9% NaCl ml/kg/day p.), Group 2: KBrO₃ (100 mg/kg (gavage), Group 3: ARB (50 mg/kg/day p.), and Group 4: KBrO₃ + ARB (100 mg/kg (gavage) + 50 mg/kg/day p.). At the end of the fifth day of the study, the rats in all groups were killed, and their brain tissues were collected. In the collected brain tissues, malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were measured, and routine histopathological examinations were made. The MDA levels in the group that was exposed to KBrO₃ were significantly higher than those in the control group (p ˂ 0.001). In comparison to the KBrO₃ group, the MDA levels in the KBrO₃ + ARB group were significantly lower (p ˂ 0.001). It was observed that SOD and CAT enzyme activity levels were significantly lower in the KBrO₃ group compared to the control group (p ˂ 0.001), while these levels were significantly higher in the KBrO₃ + ARB group than in the KBrO₃ group (p ˂ 0.001). Additionally, the group that was subjected to KBrO₃ toxicity, as well as ARB administration, had much lower levels of histopathologic signs than the group that was subjected to KBrO₃ toxicity only. Consequently, it was found that KBrO₃ exposure led to injury in the brain tissues of the rats, and using ARB was effective in preventing this injury.     

A global analysis of the determinants of alien geographical range size in birds

Aim Determining the causes of range size variation in the distributions of alien species is important for understanding the spread of invasive species. Factors influencing alien range size have been explored for some species at a regional level, but to date there has been no global analysis of an entire class. Here, we present such an analysis for birds, testing for the effects of introduction event, location and species‐level variables on alien range sizes. Location Global. Methods We used a novel dataset on the global distributions of alien bird species to test for relationships between alien range size and colonization pressure, residence time, extent of the global climatic niche, native range size, body mass and specialization, using a statistical approach based on phylogenetic generalized least squares models. We performed this analysis globally, and for separate biogeographical realms. Results Approximately half of the variation in alien bird range size is explained by colonization pressure in univariate analysis. We identified consistent effects of higher colonization pressure at global and realm levels, as well as support for effects of native range size and residence time. We found less support for effects of body mass, specialization or extent of the global climatic niche on alien range size. Main conclusions Alien bird range sizes are generally small relative to their native range sizes, and many are continuing to expand. Nevertheless, current variation is predictable, most strongly by the event‐level factor of colonization pressure. Whether a species is widespread is a better predictor of alien range size than whether a species could be widespread (estimated by global climatic niche extent), while we also find effects of residence time on alien range size. These relationships may help to identify those alien species that are more likely to spread and hence have greater environmental and economic impacts where they have been introduced.     

Species-specific evolution of telomeric and rDNA repeats in the tobacco composite genome

In order to investigate possible interactions between parental genomes in the composite genome of Nicotiana tabacum we have analyzed the organization of telomeric (TTTAGGG)_n and ribosomal gene (rDNA) repeats in the progenitor genomes Nicotiana sylvestris and Nicotiana tomentosiformis or Nicotiana otophora. Telomeric arrays in the Nicotiana species tested are heterogeneous in length ranging from 20 to 200 kb in N. sylvestris, from 20 to 50 kb in N. tomentosiformis, from 15 to 100kb in N. otophora, and from 40 to 160kb in N. tabacum. The patterns of rDNA repeats (18S, 5.8S, 25S RNA) appeared to be highly homogeneous and speciesspecific; no parental rDNA units corresponding to N. sylvestris, N. tomentosiformis or N. otophora were found in the genome of N. tabacum by Southern hybridization. The results provide evidence for a species-specific evolution of telomeric and ribosomal repeats in the tobacco composite genome.     

Synthesis of a series of fully methylated aldobiouronic acids,and β-elimination reactions of their synthetic precursors

Treatment of methyl 2,3,4-tri-O-acetyl-l-bromo-l-deoxy-α-d-glucopyranuronate severally with 2,4,6-, 2,3,6-, and 2,3,4-tri-O-methyl derivatives of methyl α-d-glucopyranoside and with methyl 4,6-O-benzylidene-3-O-methyl-α-d-glucopyranoside, in the presence of silver carbonate, afforded crystalline aldobiouronic acid derivatives in high yield. Deacetylation followed by methylation gave a series of fully methylated derivatives of laminaribiouronic, cellobiouronic, and gentiobiouronic acids, and the (1 → 2)-linked analogue. Methylation with methyl iodide and silver oxide in N,N-dimethylformamide was invariably accompanied by a small amount ofβ-elimination, with the formation of olefinic disaccharides which were also obtained by β-elimination reactions of the precursor acetates followed by methylation. Methyl 4,5-unsaturated 4-deoxyhexopyranosyluronate derivatives were the main products of the reaction, but these underwent further degradation with cleavage of the interglycosidic linkage and formation of 6-methoxycarbonyl-4-pyrone.     

Clinical and pathological significance of programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) expression in high grade serous ovarian cancer

We investigated programmed cell death 1 (PD-1) / programmed cell death ligand 1 (PD-L1) expression in high grade serous ovarian cancer (HGSOC) and its relationship to tumor infiltrating lymphocytes (TIL) and prognosis. Formalin fixed paraffin embedded (FFPE) samples of 94 HGSOC cases were included in the study. Immunohistochemical analysis (CD3, CD4, CD8, PD-1 and PD-L1) was performed. Samples were analyzed for expression of immune proteins in the peritumoral stromal and intratumoral areas, scored, and expression was correlated with overall survival, stage, and age. PD-L1 staining ratio with a score greater than 0 was found to have lower survival. There were two positive staining patterns, patchy/diffuse and patchy/focal patterns, in 24 (25.5%) cases. Considering the threshold value ≥5%, we demonstrated that the PD-L1 positive cancer cell membrane immunoreactivity rate and patchy/diffuse PD-L1 expression were 9.6% (n = 9). There was statistically significant relationship between high PD-1 scores and PD-L1 cases of ≥ 5%. A statistically significant difference was found between PD-L1 staining and survival in patients with a threshold ≥ 5%. However an appropriate rate for treatment was determined in 9.6% cases. There was a statistically significant correlation between PD-1 positive TIL score and intratumoral CD3, peritumoral stromal CD3, intratumoral CD4 and intratumoral CD8 positive cells. Survival was lower in cases with higher PD-L1 positive stromal TIL score.