Reduced genetic diversity and alteration of gene flow in a fiddler crab due to mangrove degradation

The fiddler crab Austruca occidentalis is a dominant species in mangrove forests along the East African coast. It enhances soil aeration and, through its engineering activities, makes otherwise-inaccessible food available for other marine organisms. Despite its importance, the habitat of A. occidentalis is threatened by human activities. Clearing the mangroves for salt farming and selective logging of mangroves trees continue to jeopardise mangrove ecosystems in the Western Indian Ocean. This study aims to use partial mitochondrial COI gene sequences and nuclear microsatellites to determine whether salt farming activities in mangroves have a negative impact on the genetic diversity and gene flow of A. occidentalis collected along the Tanzania coast. The level of genetic diversity for both mitochondrial DNA and nuclear microsatellites are relatively lower in samples from salt ponds compared to natural mangrove sites. Analysis of molecular variance (AMOVA) among all populations showed low but significant differentiation (COI: Fst = 0.022, P st = 0.022, P ct = 0.033, P ct = 0.018, P = A. occidentalis. Since higher genetic diversity contributes to a stable population, restoring the cleared habitats might be the most effective measures for the conservation of genetic diversity and hence adaptive potential to environmental change in this species

Genetic erosion in the snail <i>Littoraria subvittata</i> (Reid, 1986) due to mangrove deforestation

In tropical coastal ecosystems mangrove forests are important as feeding, spawning, breeding and nursery grounds for many marine species. High human population pressure in coastal areas has led to the loss and deterioration of mangrove habitats. Solar salt production can affect these habitats along the East African coast. Littorinid snails live on mangrove trees, forming an important component of the mangrove ecosystem and have been used as bioindicators of environmental health and community stress. Littoraria subvittata is the most abundant littorinid species in mangroves along the East African coast. Partial mitochondrial cytochrome oxidase subunit 1 (COI) gene sequences of 298 individuals were used to assess the impact of mangrove deforestation at salt ponds on the genetic diversity and structuring of L. subvittata populations, as well as to infer the demographic history of the species. Nucleotide and haplotype diversities were found to be lower in samples from mangroves at salt ponds than in samples from natural mangroves. The mean nucleotide diversity was 0.049 ± 0.036% and 0.115 ± 0.068% in mangroves at salt ponds and natural mangroves, respectively. The mean haplotype diversity was 0.23 ± 0.14 and 0.50 ± 0.14 in mangroves at salt ponds and natural mangroves, respectively. Analysis of molecular variance (AMOVA) detected a significant population structure (Фst = 0.049; P ct = 0.022; P st = 0.054, P st = −0.0026, P = 0.64). Reduced effective population size was observed in most samples from mangrove sites at salt ponds compared with natural mangrove. The direction of migrants was mostly from salt ponds to natural mangroves. These results show that salt ponds have a negative impact on the genetic diversity of L. subvittata populations and modify the population's genetic structure

Peningkatan Aktivitas Murid dalam Pembelajaran Bahasa Indonesia Menggunakan Pendekatan Kontekstual Kelas IV Sdn 22 Arak

Increased Activity Indonesian Students in Learning by Using Contextual Approach in Elementary School Fourth Grade 22 Arak Sintang . The purpose of this study is to describe the increase in activity in the learning Indonesian students use contextual approach . This study used a descriptive method .the research is a form of action research . This research was conducted for 3 cycles . The results of this study are as follows : baseline indicator of physical activity by 26.67 % , and the third cycle was 95.96 % . There is a difference of 69.29 % . Thus the rise of Physical Activity can be categorized as " High " . Baseline indicators of mental activity by 21.11 % , and the third cycle was 84.00 % . There is a difference of 62.89 % . Thus the increase in mental activity can be categorized as " High " . Baseline indicator of emotional activity of 23.33 % and the third cycle was 96.67 % . There is a difference of 73.34 %. Thus the increase in emotional activity can be categorized as High

Does Song Effective for EFL Students’ Listening Skill?: (A Pre-Experimental Study at Junior High School Level)

Listening ability is one of the important language skills for students in understanding foreign languages. However, students often have difficulty in developing their listening skills. Therefore, the use of songs as a tool in foreign language learning has become popular among educators and researchers. This study aims to examine the effectiveness of using songs in improving students' listening skills. In this study, a quantitative method was applied through one group pre test and post test. In the study there were 25 students as samples in the study and each of them was in grade 9. The instrument used in collecting data is a test. The results of this study show that the use of song can effectively improve students' listening skills in English. This can be seen from the mean difference between pre test (57.8) and post test (81.6). The use of songs can improve students' listening comprehension and skills through several ways, such as improving vocabulary recognition skills, practicing context understanding, and increasing students' motivation and interest in foreign language learning. However, the effectiveness of using songs in foreign language learning depends on certain factors, such as the suitability of songs with learning objectives, the suitability of songs with students' ability levels, and the way of teaching carried out by teachers or instructors

Inferring HIV-1 transmission networks and sources of epidemic spread in Africa with deep-sequence phylogenetic analysis

To prevent new infections with human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa, UNAIDS recommends targeting interventions to populations that are at high risk of acquiring and passing on the virus. Yet it is often unclear who and where these ‘source’ populations are. Here we demonstrate how viral deep-sequencing can be used to reconstruct HIV-1 transmission networks and to infer the direction of transmission in these networks. We are able to deep-sequence virus from a large population-based sample of infected individuals in Rakai District, Uganda, reconstruct partial transmission networks, and infer the direction of transmission within them at an estimated error rate of 16.3% [8.8–28.3%]. With this error rate, deep-sequence phylogenetics cannot be used against individuals in legal contexts, but is sufficiently low for population-level inferences into the sources of epidemic spread. The technique presents new opportunities for characterizing source populations and for targeting of HIV-1 prevention interventions in Africa

Osteochondroma Fracture in Young Athlete: A Case Report

Background: Osteochondroma is a benign bone tumor that most cases are asymptomatic. The symptoms may occur as a complication of osteochondroma, which is rarely happened. Surgical intervention is needed to treat the complications.Case: A 20-year old male football athlete presented with pain on his left thigh's lump after he fell during his training. Mass and tenderness on the medial side of the left distal femur were found. Plain X-Ray showed an irregular mass on the left distal femur's surface with a fracture through the stalk of pedunculated osteochondroma. The patient underwent total excision of the osteochondroma.Discussion: The fracture of the osteochondroma often occurs in teenagers because they are more active physically. It happens due to direct or indirect injury. The treatment of this fracture is controversial between observation or surgical excision. In this case report, the patient could demonstrate full weight-bearing right after the surgery.Conclusion: Fracture as a complication in osteochondroma often happens to teenagers, and surgery proved to give a good outcome in this case