181 research outputs found
SOS : save our swamps for peat's sake
The Malaysian government's scheme for the agricultural intensification of oil palm production is putting increasing pressure on lowland areas dominated by peat swamp forests.This paper focuses on the peat swamp forests of Sarawak, home to 64 per cent of the peat swamp forests in Malaysia and earmarked under the Malaysian government's Third National Agriculture Policy (1998-2010) for the development and intensification of the oil palm industry.Sarawak's tropical peat swamp forests form a unique ecosystem, where rare plant and animal species, such as the alan tree and the red-banded langur, can be found.They also play a vital role in maintaining the carbon balance, storing up to 10 times more carbon per hectare than other tropical forests. Draining these forests for agricultural purposes endangers the unique species of flora and fauna that live in them and increases the likelihood of uncontrollable peat fires, which emit lethal smoke that can pose a huge environmental risk to the health of humans and wildlife.This paper calls for a radical reassessment of current agricultural policies by the Malaysian government and highlights the need for concerted effort to protect the fragile ecosystems of Sarawak's endangered peat swamp forests
Recommended from our members
Hierarchical dynamics of individual RNA helix base pair formation and disruption
This thesis explores the RNA folding problem using single-molecule field effect transistors (smFETs) to measure the lifetimes of individual RNA base-pairing rearrangements. In the course of this research, considerable computational, chemical, and engineering contributions were developed so that the single-molecule measurements could be conducted and quantified. These advancements have allowed, on the basis of the smFET data collected herein, the quantification of a kinetic model for RNA stem-loop structures which has been generalized to quantitatively explore the phenomenological observation that an RNA found in the bacillus subtilis strain acts as a metabolite-sensing switch, allowing RNA polymerase to transcribe the messenger RNA when the metabolite is present and preventing transcription when the metabolite is absent. Together, the data presented quantify a simple model for the base pairing rearrangements that underlie RNA folding
Whistleblower Law 101: Facing Food Industry Retaliation
This Article is an annotated transcript of a panel that occurred on February 11, 2011 at the American University Washington College of Law. The podcast of the event can be found on the American University website at http://media.wcl.american.edu/mediasite/SilverlightPlayer/ Default.aspx?peid=f68cdf9c-6bab-4202-b009-26b50bf563bf. The event was co-sponsored by the Washington College of Law and the Government Accountability Project
Whistleblower Law 101: Facing Food Industry Retaliation
This Article is an annotated transcript of a panel that occurred on February 11, 2011 at the American University Washington College of Law. The podcast of the event can be found on the American University website at http://media.wcl.american.edu/mediasite/SilverlightPlayer/ Default.aspx?peid=f68cdf9c-6bab-4202-b009-26b50bf563bf. The event was co-sponsored by the Washington College of Law and the Government Accountability Project
Robotic Minimally Invasive Tools for Restricted Access Confined Spaces
A study has been performed in the design and fabrication of deployable borehole robots into confined spaces. Three robot systems have been developed to perform a visual survey of a subterranean space where for any reason humans could not enter.
A 12mm diameter snake arm was designed with a focus on the cable tensions and the failure modes for the components that make the snake arm. An iterative solver was developed to model the snake arm and algorithmically calculate the snake arms optimal length with consideration of the failure modes.
A robot was developed to extend the range capabilities of borehole robots using reconfigurable borehole robots based around established actuation and manufacturing techniques. The expected distance and weight requirements of the robot are calculated alongside the forces the robot is required to generate in order to achieve them. The whegged design incorporated into the tracks is also analysed to measure the capability of the robot over rough terrain. Finally, the experiments to find the actual driving forces of the tracks are performed and used to calculate the actual range of the robot in comparison to the target range.
The potential of reconfigurable mobile robots for deployment through boreholes is limited by the requirement for conventional gears, motors, and joints. This chapter explores the use of smart materials and innovative manufacturing techniques to form a novel concept of a self-folding robotic joint for a self-assembling robotic system. The design uses shape memory alloys fabricated in laminate structures with heaters to create folding structures
A National Study Exploring the Association Between Fluoride Levels and Dental Fluorosis
Importance: While the effects of fluoride on health have been widely researched, fewer high-quality studies examine the association of fluoride levels in water and dental fluorosis. Objective: To investigate the association between fluoride exposure from drinking water and dental fluorosis. Design, setting, and participants: This cross-sectional study used the 2013-2014 and 2015-2016 National Health and Nutrition Examination Survey (NHANES) data (January 1, 2013, through December 31, 2016). NHANES uses a complex sampling technique to develop nationally representative sample estimates of the US population that consists of interviews and physical assessments. Children and adolescents aged 6 to 15 years were included because NHANES contains their data for all 3 forms of fluoride measures: plasma fluoride levels, water levels of fluoride, and dietary fluoride supplementation. Data were analyzed from January 1 to April 30, 2023. Exposures: Water and plasma fluoride levels were measured by laboratory personnel. Dietary fluoride supplement data were self-reported. Main outcomes and measures: The Dean's Fluorosis Index was used to evaluate fluorosis status for each tooth. The dental fluorosis severity value was based on the second most affected tooth. Independent variables included plasma and water fluoride concentrations and dietary fluoride supplementation. An independent samples t test was used to compare fluoride exposures between groups, and Pearson correlation assessed the association between plasma and water fluoride levels. To assess whether fluoride exposures were associated with dental fluorosis, logistic regression analyses were conducted. Results: There were 1543 participants in the 2013-2014 NHANES cycle (weighted proportion male, 51.9%; mean [SD] age, 11.0 [2.7] years) and 1452 in the 2015-2016 cycle (weighted proportion male, 52.6%; mean [SD] age, 11.1 [2.8] years). A weighted 87.3% exhibited some degree of fluorosis in the 2013-2014 cycle and 68.2% in the 2015-2016 cycle. Higher fluoride levels in water and plasma were significantly associated with higher odds of dental fluorosis (adjusted odds ratios, 2.378 [95% CI, 2.372-2.383] in the 2013-2014 cycle and 1.568 [95% CI, 1.564-1.571] in the 2015-2016 cycle). Conclusions and relevance: The findings of this cross-sectional study suggest that exposure to higher concentrations of fluoride in water and having higher plasma levels of fluoride were associated with a greater risk of dental fluorosis. Further research can help policy makers develop policies that balance substantial caries prevention with the risk of dental fluorosis.</p
SETDB2 Links E2A-PBX1 to Cell-Cycle Dysregulation in Acute Leukemia through CDKN2C Repression
Acute lymphoblastic leukemia (ALL) is associated with significant morbidity and mortality, necessitating further improvements in diagnosis and therapy. Targeted therapies directed against chromatin regulators are emerging as promising approaches in preclinical studies and early clinical trials. Here, we demonstrate an oncogenic role for the protein lysine methyltransferase SETDB2 in leukemia pathogenesis. It is overexpressed in pre-BCR+ ALL and required for their maintenance in vitro and in vivo. SETDB2 expression is maintained as a direct target gene of the chimeric transcription factor E2A-PBX1 in a subset of ALL and suppresses expression of the cell-cycle inhibitor CDKN2C through histone H3K9 tri-methylation, thus establishing an oncogenic pathway subordinate to E2A-PBX1 that silences a major tumor suppressor in ALL. In contrast, SETDB2 was relatively dispensable for normal hematopoietic stem and progenitor cell proliferation. SETDB2 knockdown enhances sensitivity to kinase and chromatin inhibitors, providing a mechanistic rationale for targeting SETDB2 therapeutically in ALL
Hematopoietic stem cell quiescence and DNA replication dynamics maintained by the resilient β-catenin/Hoxa9/Prmt1 axis
Maintenance of quiescence and DNA replication dynamics are two paradoxical requirements for the distinct states of dormant and active hematopoietic stem cells (HSCs), which are required to preserve the stem cell reservoir and replenish the blood cell system in response to hematopoietic stress respectively. Here, we show that key self-renewal factors, β-catenin or Hoxa9, largely dispensable for HSC integrity in fact have dual functions in maintaining quiescence and enabling efficient DNA replication fork dynamics to preserve the functionality of hematopoietic stem and progenitor cells (HSPCs). While β-catenin or Hoxa9 single knockout (KO) exhibited mostly normal hematopoiesis, their co-inactivation led to severe hematopoietic defects stemmed from aberrant cell cycle, DNA replication and damage in HSPCs. Mechanistically, β-catenin and Hoxa9 function in a compensatory manner to sustain key transcriptional programs that converge on the pivotal downstream target and epigenetic modifying enzyme, Prmt1, which protects the quiescent state and ensures an adequate supply of DNA replication and repair factors to maintain robust replication fork dynamics. Inactivation of Prmt1 phenocopied both cellular and molecular phenotypes of β-catenin/Hoxa9 combined KO, which at the same time could also be partially rescued by Prmt1 expression. The discovery of the highly resilient β-catenin/Hoxa9/Prmt1 axis in protecting both quiescence and DNA replication dynamics essential for HSCs at different key states provides not only novel mechanistic insights into their intricate regulation but also a potential tractable target for therapeutic intervention
- …