Dark retweets: investigating non-conventional retweeting patterns

Retweets are an important mechanism for recognising propagation of information on the Twitter social media platform. However, many retweets do not use the official retweet mechanism, or even community established conventions, and these "dark retweets" are not accounted for in many existing analysis. In this paper, a comprehensive matrix of tweet propagation is presented to show the different nuances of retweeting, based on seven characteristics: whether it is proprietary, the mechanism used, whether it is directed to followers or non-followers, whether it mentions other users, if it is explicitly propagating another tweet, if it links to an original tweet, and what is the audience it is pushed to. Based on this matrix and two assumptions of retweetability, the degrees of a retweet's "darkness" can be determined. This matrix was evaluated over 2.3 million tweets and it was found that dark retweets amounted to 12.86% (for search results less than 1500 tweets per URL) and 24.7% (for search results including more than 1500 tweets per URL) respectively. By extrapolating these results with those found in existing studies, potentially thousands of retweets may be hidden from existing studies on retweets

Urban Cholera transmission hotspots and their implications for Reactive Vaccination: evidence from Bissau city, Guinea Bissau

Use of cholera vaccines in response to epidemics (reactive vaccination) may provide an effective supplement to traditional control measures. In Haiti, reactive vaccination was considered but, until recently, rejected in part due to limited global supply of vaccine. Using Bissau City, Guinea-Bissau as a case study, we explore neighborhood-level transmission dynamics to understand if, with limited vaccine and likely delays, reactive vaccination can significantly change the course of a cholera epidemic

Research Productivity of Returnees from Study Abroad in Korea, Malaysia, and Hong Kong

This study analyzes whether academics with advanced degrees from foreign universities are more research productive than their domestic counterparts in the three selected East Asian higher education systems – Korea, Hong Kong, and Malaysia. The three systems have relatively large proportions of foreign degree holders among their professoriates. The data for this study is drawn from the Changing Academic Profession survey. In our negative binominal regression analysis, we found that foreign degree holders are not more research productive than their colleagues with domestic degrees, and even slightly less productive than domestic degree holders in soft disciplines (arts, humanities, and social sciences) in Korea unless they have further foreign post-doc experience after their PhD. Furthermore, foreign degree holders are less productive in hard disciplines (natural sciences, engineering, and bio-medical sciences) in Malaysia. Finally, we discuss the findings and attribute them to contextual differences between the three localities.postprin

Occurrence of Blastocystis in Water of Two Rivers from Recreational Areas in Malaysia

This study reports the occurrence of Blastocystis in water from two rivers, Sungai Congkak and Sungai Batu, located in recreational areas in Malaysia. This protozoan was detected in samples from both rivers with an average of 33.3% and 22.1%, respectively. It was detected highest at the downstream (73.8% and 33.8%) followed by midstream (17.5% and 25.0%) and upstream (8.8% and 7.5%) stations, with additionally higher detection during holidays (with average 47.5% and 30.8%) than week days (with average 19.2% and 13.3%), in both rivers, respectively. There was a strong association with the daily activities of locals and visitors, who came for water recreational activities, mainly located between midstream and downstream and was observed to be higher at Sungai Congkak. The detection of Blastocystis in these rivers' water implies that this protozoan could potentially be transmitted to humans by the waterborne route. Pearson correlation analysis showed that their occurrence was significantly correlated with faecal coliforms count; inconsistent correlation with dissolved oxygen, temperature and turbidity and no correlation with pH, conductivity and rainfall for both rivers. The correlation of coliforms and Blastocystis suggests the source of the Blastocystis in the water body is likely to be faecal

High Hepatitis E Seroprevalence Among Displaced Persons in South Sudan.

AbstractLarge protracted outbreaks of hepatitis E virus (HEV) have been documented in displaced populations in Africa over the past decade though data are limited outside these exceptional settings. Serological studies can provide insights useful for improving surveillance and disease control. We conducted an age-stratified serological survey using samples previously collected for another research study from 206 residents of an internally displaced person camp in Juba, South Sudan. We tested serum for anti-HEV antibodies (IgM and IgG) and estimated the prevalence of recent and historical exposure to the virus. Using data on individuals' serostatus, camp arrival date, and state of origin, we used catalytic transmission models to estimate the relative risk of HEV infection in the camp compared with that in the participants' home states. The age-adjusted seroprevalence of anti-HEV IgG was 71% (95% confidence interval = 63-78), and 4% had evidence of recent exposure (IgM). We estimated HEV exposure rates to be more than 2-fold (hazard ratio = 2.3, 95% credible interval = 0.3-5.8) higher in the camp than in the participants' home states, although this difference was not statistically significant. HEV transmission may be higher than previously appreciated, even in the absence of reported cases. Improved surveillance in similar settings is needed to understand the burden of disease and minimize epidemic impact through early detection and response

IMPROVING FERTILITY OF ACID SULFATE SOIL USING VARIOUS LIME SOURCES FOR RICE GROWN IN MALAYSIA

The main problems of acid sulfate soils are high acidity and Al and/or Fe toxicity to the soil. This problem causes rice root inhibition, hence retard plant nutrient uptake for its growth. Improving these conditions is important; hence, liming seems to be a common practice to ameliorate this soil, especially for rice cultivation. A study was conducted to evaluate the effects of applying ground magnesium limestone (GML), hydrated lime and liquid lime on the growth of rice under glasshouse conditions. MR 219 rice variety was used in this experiment. It was found that the application of 4 t ha-1 of GML had produced the highest rice yield of 8.2 t ha-1 under glasshouse condition. The result showed that as panicle length increase, spikelet per panicle also increases. Relative rice yield is negatively correlated with the soil pH, and this indicates that as soil acidity increase (observed with pH between 2 to 3), the rice yield decreases and vice versa. At harvest, due to liming practices, the soil pH exceeded 6 for all the treatment. It was also observed that as soil exchangeable Ca increase, soil pH also increases. Among the treatment, soil treated with 2 t ha-1 of hydrated lime gave the highest exchangeable Ca in the soil of 11.86 cmolc kg-1 soil with Ca concentration of 0.12% in the root. It was observed that liming increases soil pH and exchangeable cations in the soil. Therefore, liming is essential to ameliorate the acid sulfate soils for rice cultivation

Problematising international placements as a site of intercultural learning

This paper theorises some of the learning outcomes of a three-year project concerning student learning in international social work placements in Malaysia. The problematic issue of promoting cultural and intercultural competence through such placements is examined, where overlapping hegemonies are discussed in terms of isomorphism of social work models, that of the nation state, together with those relating to professional values and knowledge, and the tyrannies of received ideas. A critical discussion of cultural competence as the rationale for international placements is discussed in terms of the development of the graduating social worker as a self-reflexive practitioner. The development of sustainable international partnerships able to support student placement and the issue of non-symmetrical reciprocation, typical of wide socio-economic differentials across global regions, is additionally discussed

Subcellular mRNA Localization Regulates Ribosome Biogenesis in Migrating Cells

Translation of ribosomal protein-coding mRNAs (RP-mRNAs) constitutes a key step in ribosome biogenesis, but the mechanisms that modulate RP-mRNA translation in coordination with other cellular processes are poorly defined. Here, we show that subcellular localization of RP-mRNAs acts as a key regulator of their translation during cell migration. As cells migrate into their surroundings, RP-mRNAs localize to the actin-rich cell protrusions. This localization is mediated by La-related protein 6 (LARP6), an RNA-binding protein that is enriched in protrusions. Protrusions act as hotspots of translation for RP-mRNAs, enhancing RP synthesis, ribosome biogenesis, and the overall protein synthesis in migratory cells. In human breast carcinomas, epithelial-to-mesenchymal transition (EMT) upregulates LARP6 expression to enhance protein synthesis and support invasive growth. Our findings reveal LARP6-mediated mRNA localization as a key regulator of ribosome biogenesis during cell migration and demonstrate a role for this process in cancer progression downstream of EMT

Fatigue Crack Detection Using Nonlinear Acoustic-Analysis Of Vibro-Acoustic Modulation

Nonlinear vibro-acoustic is a highly reliable and sensitive method for damage detection. It is a method based on propagation of high frequency acoustic waves in solid structures with low-frequency excitation. Interaction of the acoustic wave with material or geometry properties changes caused wave distortion effects. The causes called nonlinear acoustic effects are amplified with the low frequency excitation. Nonlinear acoustic-acoustic modulations are investigated for fatigue crack detection. The focus is on vibro-acoustic wave moduIations used for crack detection in aluminium. Experimental works are performed to investigate the effect of crack characteristics, i.e. crack lengths and crack modes, on vibro-acoustic effects intensity. Nonlinear acoustic tests are performed for the uncracked and cracked aluminium plates. The analyses results show that there are many nonlinear phenomena (i-e. hysteresis and classical Ist order perturbation) involved in the vibro-acoustic wave modulations. The nonlinear modulations produced by the low-frequency modal excitation and high-frequency ultrasonic excitation can be used effectively for fatigue crack detection

An ERK1/2-driven RNA-binding switch in nucleolin drives ribosome biogenesis and pancreatic tumorigenesis downstream of RAS oncogene

Oncogenic RAS signaling reprograms gene expression through both transcriptional and post‐transcriptional mechanisms. While transcriptional regulation downstream of RAS is relatively well characterized, how RAS post‐transcriptionally modulates gene expression to promote malignancy remains largely unclear. Using quantitative RNA interactome capture analysis, we here reveal that oncogenic RAS signaling reshapes the RNA‐bound proteomic landscape of pancreatic cancer cells, with a network of nuclear proteins centered around nucleolin displaying enhanced RNA‐binding activity. We show that nucleolin is phosphorylated downstream of RAS, which increases its binding to pre‐ribosomal RNA (rRNA), boosts rRNA production, and promotes ribosome biogenesis. This nucleolin‐dependent enhancement of ribosome biogenesis is crucial for RAS‐induced pancreatic cancer cell proliferation and can be targeted therapeutically to inhibit tumor growth. Our results reveal that oncogenic RAS signaling drives ribosome biogenesis by regulating the RNA‐binding activity of nucleolin and highlight a crucial role for this mechanism in RAS‐mediated tumorigenesis