The dynamics of social networks among female Asian elephants

<p>Abstract</p> <p>Background</p> <p>Patterns in the association of individuals can shed light on the underlying conditions and processes that shape societies. Here we characterize patterns of association in a population of wild Asian Elephants at Uda Walawe National Park in Sri Lanka. We observed 286 individually-identified adult female elephants over 20 months and examined their social dynamics at three levels of organization: pairs of individuals (dyads), small sets of direct companions (ego-networks), and the population level (complete networks).</p> <p>Results</p> <p>Corroborating previous studies of this and other Asian elephant populations, we find that the sizes of elephant groups observed in the field on any particular day are typically small and that rates of association are low. In contrast to earlier studies, our longitudinal observations reveal that individuals form larger social units that can be remarkably stable across years while associations among such units change across seasons. Association rates tend to peak in dry seasons as opposed to wet seasons, with some cyclicity at the level of dyads. In addition, we find that individuals vary substantially in their fidelity to companions. At the ego-network level, we find that despite these fluctuations, individuals associate with a pool of long-term companions. At the population level, social networks do not exhibit any clear seasonal structure or hierarchical stratification.</p> <p>Conclusions</p> <p>This detailed longitudinal study reveals different social dynamics at different levels of organization. Taken together, these results demonstrate that low association rates, seemingly small group sizes, and fission-fusion grouping behavior mask hidden stability in the extensive and fluid social affiliations in this population of Asian elephants.</p

Masalah Sekuriti Makanan Sebelum dan Semasa Pandemik Covid-19: Kajian kes di New Zealand

Kajian ini bertujuan untuk menelusuri dinamika masalah sekuriti makanan yang berlaku di kalangan rakyat sebelum dan semasa pandemik Covid-19. Berlandaskan kepada kajian kes ke atas negara New Zealand, kajian ini akan merungkaikan isu sekuriti makanan yang dialami oleh rakyat New Zealand dalam tempoh dua dekad kebelakangan ini dan impak pandemik Covid-19 ke atas masalah sekuriti makanan di kalangan rakyat. Kajian ini mendapati bahawa dalam tempoh 20 tahun ini, sebilangan penduduk New Zealand sudah berhadapan dengan isu akses kepada makanan terutamanya golongan etnik Maori dan Pasifik, gelandangan, kanak-kanak, ibu/bapa tunggal, dan orang kurang upaya. Mereka berhadapan dengan isu tidak cukup makanan yang antaranya menjejaskan nutrisi, kestabilan mental dan hubungan kekeluargaan. Masalah sekuriti makanan yang dihadapi oleh rakyat New Zealand diperburukkan lagi apabila berlakunya pandemik Covid-19 pada akhir tahun 2019. Pandemik ini bukan sahaja telah mencetuskan krisis kesihatan tetapi ia juga telah menyebabkan krisis ekonomi yang bersama-samanya menimbulkan ancaman terhadap sekuriti makanan di kalangan ramai lagi rakyat New Zealand. Antaranya, pandemik Covid-19 telah menjejaskan akses kepada makanan dari segi ketiadaan sumber pendapatan mencukupi untuk membeli makanan kerana lockdown atau dibuang kerja; gangguan kepada sistem rantaian bekalan bila berlakunya kekurangan produk penting disebabkan oleh pembelian panik dan masalah pembungkusan; kenaikan harga barangan terutamanya sayuran dan buah-buahan segar yang menjejaskan pengambilan nutrisi; dan penutupan bank makanan serta perniagaan kecil semasa tempoh lockdown kerana tidak dikategorikan sebagai essential. Kajian ini menggunakan pendekatan analisis sejarah berdasarkan penggunaan sumber primer (khususnya dokumen, laporan, akhbar) dan sumber sekunder

Holocentric Chromosomes of Luzula elegans Are Characterized by a Longitudinal Centromere Groove, Chromosome Bending, and a Terminal Nucleolus Organizer Region

The structure of holocentric chromosomes was analyzed in mitotic cells of Luzula elegans. Light and scanning electron microscopy observations provided evidence for the existence of a longitudinal groove along each sister chromatid. The centromere-specific histone H3 variant, CENH3, colocalized with this groove and with microtubule attachment sites. The terminal chromosomal regions were CENH3-negative. During metaphase to anaphase transition, L. elegans chromosomes typically curved to a sickle-like shape, a process that is likely to be influenced by the pulling forces of microtubules along the holocentric axis towards the corresponding microtubule organizing regions. A single pair of 45S rDNA sites, situated distal to Arabidopsis-telomere repeats, was observed at the terminal region of one chromosome pair. We suggest that the 45S rDNA position in distal centromere-free regions could be required to ensure chromosome stability. Copyright (C) 2011 S. Karger AG, Base

Patients' perception regarding the influence of individual and social vulnerabilities on the adherence to tuberculosis treatment: a qualitative study

Background: Tuberculosis remains an important disease which mainly affects the majority of vulnerable individuals in society, who are subjected to poor living conditions and difficulties to access the services of public health. Under these circumstances, the present study aims to understand patients' perception in relation to the influence of individual and social vulnerabilities on the adherence to tuberculosis treatment. Methods: A qualitative descriptive cross sectional study was conducted in one large municipality at the state of Paraiba, Northeast of Brazil. The study subjects, who were residents of the study site, covered all tuberculosis cases diagnosed between March and June 2015. The sample was defined by the criteria of response saturation. All interviews were audio recorded, and data analysis was developed through the hermeneutic dialectic method and the theory of Generative Route Sense. The project was approved by the Research Ethics Committee of the University of Sao Paulo (USP). Results: A total of 13 individuals were interviewed and the responses were identified into two analytical categories: the difficulties they had and the enabling factors they could mention during their tuberculosis treatment. Patients brought up social exclusion as an obstacle to treatment adherence, which, along with stigmatization, weakened their link with family members and health professionals. Moreover, economic precariousness was a major hindrance to the maintenance of a proper diet and transportation access to health centers. However, social support and directly observed treatment helped to break down barriers of prejudice and to promote individual and family empowerment. Finally, patients also reported that their will to live and faith gave them the strength to continue with the treatment. Conclusions: According to patients in this study, social support and the strengthening of links with family members and health professionals may reduce social exclusion and other difficulties they face, thus encouraging them to the adhere to tuberculosis treatment.Univ Estadual Paraiba, Campina Grande, Paraiba, BrazilUniv Fed Rio Grande do Norte, Natal, RN, BrazilUniv Sao Paulo, Escola Enfermagem, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Enfermagem, Sao Paulo, BrazilFac Santa Maria, Cajazeiras, Paraiba, BrazilUniv Fed Sao Paulo, Escola Paulista Enfermagem, Sao Paulo, BrazilWeb of Scienc

Effect of propolis gel on the in vitro reduction of dentin permeability

OBJECTIVE: The aim of this study was to evaluate the capacity of potassium oxalate, fluoride gel and two kinds of propolis gel to reduce the hydraulic conductance of dentin, in vitro. MATERIAL AND METHODS: The methodology used for the measurement of hydraulic conductance of dentin in the present study was based on a model proposed in literature. Thirty-six 1-mm-thick dentin discs, obtained from extracted human third molars were divided into 4 groups (n=9). The groups corresponded to the following experimental materials: GI-10% propolis gel, pH 4.1; GII-30% propolis gel; GIII-3% potassium oxalate gel, pH 4,1; and GIV-1.23% fluoride gel, pH 4.1, applied to the dentin under the following surface conditions: after 37% phosphoric acid and before 6% citric acid application. The occluding capacity of the dentin tubules was evaluated using scanning electron microscopy (SEM) at ×500, ×1,000 and ×2,000 magnifications. Data were analyzed statistically by two-way ANOVA and Tukey's test at 5% significance level. RESULTS: Groups I, II, III, IV did not differ significantly from the others in any conditions by reducing in hydraulic conductance. The active agents reduced dentin permeability; however they produced the smallest reduction in hydraulic conductance when compared to the presence of smear layer (P<0.05). The effectiveness in reducing dentin permeability did not differ significantly from 10% or 30% propolis gels. SEM micrographs revealed that dentin tubules were partially occluded after treatment with propolis. CONCLUSIONS: Under the conditions of this study, the application of 10% and 30% propolis gels did not seem to reduce the hydraulic conductance of dentin in vitro, but it showed capacity of partially obliterating the dentin tubules. Propolis is used in the treatment of different oral problems without causing significant great collateral effects, and can be a good option in the treatment of patients with dentin sensitivity