Search

© This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/ Deposited by shareyourpaper.org and openaccessbutton.org. We've taken reasonable steps to ensure this content doesn't violate copyright. However, if you think it does, you can request a takedown by emailing help@openaccessbutton.org.

Impaired quality of life due to atrial fibrillation (AF), which often includes decreased activity level, is an indication for ablation. However, the impact of ablation for AF on activity is poorly understood.The purpose of this study was to assess the impact of ablation on activity minutes per day using continuous accelerometer data from cardiac implantable electronic devices (CIEDs).Using the Optum® Health Record dataset (2007-2019) linked with the Medtronic CareLink® database, we identified patients who had a CIED with AF detection and accelerometer capabilities. Patients with a device that transmitted heart rhythm and activity data ≥3 months before and ≥12 months after ablation were included in analysis. The associations between ablation and activity minutes were assessed for each CIED type.Of 4297 eligible patients who underwent AF ablation, 409 (9.5%) (65% male; age 67.3 ± 9.8 years; 64% paroxysmal AF) were included in analysis. The average AF burden and activity minutes per day preablation were 30.9% ± 37.4% and 175 ± 99 minutes, respectively. After ablation, relative AF burden decreased by 75.1% ± 53.2% (P.001). There was no change in activity minutes per day after ablation in the entire cohort (average change -0.10 ± 36.2 minutes; P = .96). There were also no clinically significant changes in activity minutes postablation in subgroups based on CIED, season of ablation, quartile of AF burden change, and quartile of age at the time of ablation.There were no clinically significant changes in activity minutes per day in patients with CIEDs after ablation for AF.

Guidelines recommend a confirmed diagnosis of atrial fibrillation (AF) to initiate oral anticoagulation in cryptogenic stroke (CS) patients. However, the intermittent nature of AF can make detection challenging with intermittent short-term cardiac monitoring.The purpose of this retrospective cohort study was to examine post-CS utilization of cardiac monitoring and associated clinical outcomes.Adults with incident hospitalization for CS were identified in the Optum® claims database and assessed for cardiac monitoring received poststroke. Patient were stratified into those with a long-term insertable cardiac monitor (ICM) vs external cardiac monitor (ECM) only. The timing of ICM placement poststroke was treated as a time-dependent covariate. The clinical outcomes of interest were time to AF diagnosis, oral anticoagulation usage, and all-cause mortality.A total of 12,994 patients met selection criteria for the analysis, of whom 1949 (15%) received an ICM and 11,045 (85%) received ECM only. In those who had received an ECM as their first monitoring modality, only 4.4% moved on to receive an ICM for longer-term monitoring. Use of ECM before ICM was associated with a longer time to AF diagnosis (median 336 vs 194 days). Compared to those with ECM only, ICM patients had a significantly lower rate of death (hazard ratio [HR] 0.70;In a real-world study of CS patients, prolonged cardiac monitoring was associated with higher rates of AF detection and treatment, and higher odds of survival.

Compared with short-term electrocardiogram (ECG) monitors, insertable cardiac monitors (ICMs) have been shown to increase atrial fibrillation (AF) detection rates and the opportunity to treat recurrent AF in patients postablation.To examine healthcare utilization and clinical outcomes following AF ablation, in patients with vs without ICM.Retrospective analysis pooling Optum Clinformatics and Medicare Fee-for-service 5% Sample claims databases. Patients with an AF ablation between January 1, 2011, and March 31, 2018 who received an ICM implant within 1 year pre-/postablation were propensity score matched 1:3 to patients without ICM. Outcomes included AF-related healthcare utilization, medication use, and occurrence of composite severe cardiovascular events (stroke / transient ischemic attack, major bleeds, systemic embolism, AF- or heart failure-related hospitalization, or death).A total of 1000 ICM patients and 2998 non-ICM patients were included. During mean follow-up of 33 ± 16 months postablation, ICM patients experienced significantly fewer severe cardiovascular events (1.09 ± 2.22 vs 1.37 ± 4.19,A shift from acute, reactive care to routine outpatient management was observed in patients with long-term ECG monitoring. Results suggest closer patient management in patients with long-term monitoring after an AF ablation and an improvement in outcomes, at similar overall cost.

Synthetic aperture radar (SAR) has great potential for timely monitoring of flood information as it penetrates the clouds during flood events. Moreover, the proliferation of SAR satellites with high spatial and temporal resolution provides a tremendous opportunity to understand the flood risk and its quick response. However, traditional algorithms to extract flood inundation using SAR often require manual parameter tuning or data annotation, which presents a challenge for the rapid automated mapping of large and complex flooded scenarios. To address this issue, we proposed a segmentation algorithm for automatic flood mapping in near-real-time over vast areas and for all-weather conditions by integrating Sentinel-1 SAR imagery with an unsupervised machine learning approach named Felz-CNN. The algorithm consists of three phases: (i) super-pixel generation; (ii) convolutional neural network-based featurization; (iii) super-pixel aggregation. We evaluated the Felz-CNN algorithm by mapping flood inundation during the Yangtze River flood in 2020, covering a total study area of 1,140,300 km2. When validated on fine-resolution Planet satellite imagery, the algorithm accurately identified flood extent with producer and user accuracy of 93% and 94%, respectively. The results are indicative of the usefulness of our unsupervised approach for the application of flood mapping. Meanwhile, we overlapped the post-disaster inundation map with a 10-m resolution global land cover map (FROM-GLC10) to assess the damages to different land cover types. Of these types, cropland and residential settlements were most severely affected, with inundation areas of 9,430.36 km2 and 1,397.50 km2, respectively, results that are in agreement with statistics from relevant agencies. Compared with traditional supervised classification algorithms that require time-consuming data annotation, our unsupervised algorithm can be deployed directly to high-performance computing platforms such as Google Earth Engine and PIE-Engine to generate a large-spatial map of flood-affected areas within minutes, without time-consuming data downloading and processing. Importantly, this efficiency enables the fast and effective monitoring of flood conditions to aid in disaster governance and mitigation globally.

Background Reducing atrial fibrillation (AF)-related stroke requires timely AF diagnosis, but the optimal monitoring strategy is unknown. Objective We used insertable cardiac monitor (ICM) data from the REVEAL AF study to compare AF detection rates by various short-term continuous monitoring (STM) strategies. Methods and Results Patients without known AF, but with CHADS2 scores ≥3 (or = 2 with ≥1 additional AF risk factor) received an ICM for AF detection. One-time STM strategies were assessed by computing AF incidence at 1, 2, 7, 14, and 30 days post-ICM insertion. Repeated STM strategies (quarterly 24-hour, 48-hour, 7-day, or monthly 24-hour monitoring) were modeled by randomly selecting day(s) within a 30-day window around each nominal evaluation date over a 1-year period (simulated 10,000 times). Endpoints included AF ≥6 minutes, AF ≥1 hour, and daily AF burden ≥1 and ≥ 5.5 hours. The impact of compliance on AF detection was evaluated using daily compliance rates of 85%, 75%, 65% and 55% during follow-up months 1-3, 4-6, 7-9, and 9-12, respectively. Based on data from 385 patients (71.5 ± 9.9 years; CHADS2 score 3.0 ± 1.0) the incidence of AF ≥6 minutes via ICM at 12 months was 27.1% (95% CI, 22.5-31.5%). This exceeded the range of estimated rates from all modeled one-time and repeated STM strategies (0.8% for 24-hour Holter monitoring to 10.6% for quarterly 7-day monitoring). Findings were similar for all AF endpoints. Modeled non-compliance reduced AF detection by 4.5% to 22.9%. Conclusions Most AF episodes detected via ICMs would go undetected via conventional STM strategies, thus preventing optimal prophylaxis for adverse consequences.

The REVEAL AF study demonstrated a high incidence of previously undetected atrial fibrillation (AF) using insertable cardiac monitors (ICMs) in patients with risk factors for AF and stroke. This analysis evaluated whether ICM monitoring led to changes in clinical management after AF detection. Patients with CHADS2 scores ≥3 (or =2 with ≥1 additional AF risk factor) but no history of AF received an ICM and were followed 18 to 30 months. Physicians recorded changes in clinical management in response to AF detection at scheduled (every 6 months) and unscheduled follow-up visits. Changes in clinical management included oral anticoagulation, rhythm or rate control pharmacotherapy, cardioversion, ablation, and cardiac subspecialist referral. In 387 patients who met inclusion criteria and received an ICM, AF was found in 115. A change in clinical management was taken in 87 patients with AF (76%). In 80 of these 87, a change was taken at the first visit after AF detection. In total, 31 patients (27%) with AF had ≥2 visits at which changes in clinical management were taken. The most common change was initiation of oral anticoagulation (n = 73, 63% of patients with AF). Patients with a change in clinical management at the first visit after AF detection tended to have longer AF episodes and a higher maximal daily AF burden compared with AF patients for whom no change was taken (longest episode: 52 vs 28 minutes; maximal daily AF burden:112 vs 23 minutes). Changes in management more frequently occurred at visits where patients reported AF-compatible symptoms (65% vs 46% of visits, p = 0.01). In conclusion, ICM monitoring to identify AF guides both immediate and long-term patient management in a population at high risk for stroke.

Objectives The purpose of this study was to compare the effectiveness of bucindolol with that of metoprolol succinate for the maintenance of sinus rhythm in a genetically defined heart failure (HF) population with atrial fibrillation (AF). Background Bucindolol is a beta-blocker whose unique pharmacologic properties provide greater benefit in HF patients with reduced ejection fraction (HFrEF) who have the beta1-adrenergic receptor (ADRB1) Arg389Arg genotype. Methods A total of 267 HFrEF patients with a left ventricular ejection fraction (LVEF) Results The hazard ratio (HR) for the primary endpoint was 1.01 (95% confidence interval [CI]: 0.71 to 1.42), but trends for bucindolol benefit were observed in several subgroups. Precision therapeutic phenotyping revealed that a differential response to bucindolol was associated with the interval of time from the initial diagnoses of AF and HF to randomization and with the onset of AF relative to that of the initial HF diagnosis. In a cohort whose first AF and HF diagnoses were Conclusions Pharmacogenetically guided bucindolol therapy did not reduce the recurrence of AF/AFL or ACM compared to that of metoprolol therapy in HFrEF patients, but populations were identified who merited further investigation in future phase 3 trials.

Landslides triggered by monsoon rainfall are a recurring hazard that lead to loss of life and cause enormous property and infrastructure damage in the Indian Himalaya. This study is focused on understanding the role of extreme rainfall and physical factors in causing landslides in the Indian Himalaya, particularly in the Mandakini Catchment where an enormous landslide and flood disaster occurred in June 2013 following a two-day extreme rainfall event. Results indicate that sub-daily extreme rainfall depths causing landslides vary with elevation across the catchment. Antecedent rainfall six days prior to the extreme rainfall event was found to have substantial depths that could have primed the area for landslides. Except for aspect of slopes, the causative factors including land use/land cover, lithology, elevation, slope, river network, distance to roads, and total extreme rainfall as a triggering factor were found to be statistically significant in causing landslides in the catchment. The final product of the study is a new landslide susceptibility map that better delineates the landslide prone regions in the disaster-prone Mandakini Catchment after the June 2013 extreme rainfall event. The Map was prepared using logistic regression that shows medium and high susceptibility zones at upper sections of the catchment as well as along the Mandakini River and its tributaries where major sacred shrines, tourist spots and human establishments are located.

To understand the distribution of soil elemental concentrations and their potential sources of trace metal contamination in the high-conservation Nee Soon freshwater swamp forest in Singapore, we analyzed samples from 227 surface and 35 subsurface (auger profiles) locations. Our assessment involved distribution maps, principle component analysis, cluster analysis, and correlation analysis of element concentrations determined from a mixed acid digestion and measurement on an ICP-MS. We found a distinct zonation in the distribution of several elements (Ba, Cr, Cu, Fe, Mn, Pb, Sr, Ti, V, and Zn) between the upper and lower catchment that gives an erroneous notion of widespread contamination in the lower catchment. We believe this zonation is natural, likely related to differences in the underlying geology. However, Cu, Pb, and Sb concentrations were greatly enriched by anthropogenic activities on military training lands in the lower catchment, firing ranges in particular. Barium, Sr, and Zn also appear to be enriched in the lower part of the catchment, possibly from anthropogenic activities including military activity and roads. Although soils in the catchment are not highly contaminated, isolated areas with high concentrations of Cu, Pb and Sb may warrant management attention given the sensitive nature of the urban forest, which includes the last remaining fresh water swamp forest in Singapore.

As forest loss is accelerating in tropical mountains globally, protected areas (PAs) are seen as bastions to protect sensitive ecosystems, preserve biodiversity, and safeguard headwater catchments from degradation. However, the effectiveness of PAs in preventing forest conversion has rarely been determined. Complicating the issue is that many PAs are inhabited to some extent by long-standing residents, causing illegal logging that is commonly reported. To assess the effectiveness of PAs in preserving forests, as well as investigate the drivers of forest loss in/near PAs, we compare forest loss rates inside and outside PAs before and after their establishment in a tropical mountain region (northern Thailand, the epicenter of mainland Southeast Asia, including 84 PAs). Over the 17-year period from 2000 to 2016, we found that the percentage of forest loss was lower within the PAs than outside (1.69% versus 4.94%). Mean annual forest loss in the PAs was 20% of that in unprotected area. Total forest loss inside PAs included 888.12 km2 (1.93%) in national parks, 325.18 km2 (1.34%) in wildlife sanctuaries/conservation areas and 16.37 km2 (0.65%) in no hunting areas. Forest loss also tended to be highest along boundaries within a 300-m buffer both inside and outside the PAs. Using gradient boosting decision trees, we determined that accessibility variables (elevation, and distance to road) and population were key drivers associated with forest loss in PAs. Further, we found a two-year lagged correlation between forest loss in PAs and international maize price (R2 = 0.73, p < 0.001), indicating the sensitivity of forest loss in some locations to commodity agriculture trends. Finally, we acknowledge the difficulty of managing forest loss in PAs because of the large populations of people living within the boundaries who rely on forest products to support their livelihoods, as well as difficulties in enforcing illegal logging laws.

Recent flood disasters in Nepal have been the result of a combination of a fast-growing vulnerability of the local population and variable, possibly changing climatic conditions. In the future, flood disasters are likely to occur if vulnerability does not decrease. Nonetheless, the current state of flood disaster governance in Nepal, including flood risk assessment, is limited. To better inform policy and flood disaster governance, we created a flood risk assessment model that maps and quantifies the vulnerability of populations in flood-prone areas in Sindhupalchok District, Nepal. Three scenarios were considered in the model: a baseline-flood scenario, a medium-extreme-flood scenario, and a high-extreme-flood scenario. Overall, the model demonstrates that the local population is indeed vulnerable to flood risk, and increasingly for extreme floods. The model results indicate the following: (1) vulnerability to flood risk increases significantly from the baseline-flood scenario to the two extreme-flood scenarios; (2) houses are especially vulnerable to flood risk in the Village Development Committees (VDCs) of Gloche, Pagretar, Tatopani, Kadambas, and Bahrabise; and (3) income and food from crop production are most vulnerable to flood risk in the VDCs of Gloche, Fulpingdanda, Kadambas, Tatopani, and Batase. Based on these results, moving towards improved flood disaster governance, we make recommendations to improve measures for flood risk reduction with a focus on implementing flood early warning systems, clarifying the assignment of roles and responsibilities to stakeholders in flood risk governance, and increasing the development/use of flood risk assessment models.

Constraining the contribution of mangrove-derived carbon in tidal creeks is fundamental to understanding the fate of mangrove primary production and the role of mangroves as coastal carbon sinks. Porewater measurements and 24-h time series in a mangrove tidal creek were conducted during the dry and wet season, and over contrasting tidal ranges at the Can Gio Biosphere Reserve, Vietnam. Surface water carbon concentrations (dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), partial pressure of carbon dioxide (pCO2)) and their respective δ13C values were correlated with radon, suggesting that porewater input drives mangrove-derived carbon in the tidal creek. Based on three complementary mixing models, porewater input contributed to about 30% of the water volume and 46% to 100% of DOC and DIC pools in the tidal creek at low tide, with variabilities between seasons and tidal amplitudes. The creek carbon pool was 88% DIC, 6% DOC, and 6% particulate organic carbon (POC). The pCO2 values during the wet season (2973–16,495 μatm) were on average 5-fold higher than during the dry season (584–2946 μatm). This was explained by a potential greater mineralization attributed to higher organic matter availability and residual humidity that stimulate bacterial activity, and by a potential tidal dilution changing the pCO2/DIC ratio as suggested by the Revelle factor. Consequently, average CO2 evasion from the creek was estimated at 327–427 mmolC m−2 d−1 during the wet season and 92–213 mmolC m−2 d−1 during the dry season, using two independent approaches. Tidal amplitude seemed to influence porewater input and its carbon loads, with a higher contribution during frequent and high tidal amplitudes (symmetric). However, the highest input occurred in a tidal cycle which was preceded by tidal cycle of low amplitude (asymmetric). We explain this ambiguity by the influence of both, rapid water turnover intensifying porewater exchange, and long water residence time enhancing carbon load in porewater.

The characteristics of a reef-top boulder field created by a local submarine landslide tsunami are presented for the first time. Our examination of large reef-derived boulders deposited by the 1953 tsunami near Suva City, Fiji, revealed that shorter-than-normal-period tsunami waves generated by submarine landslides can create a boulder field resembling a storm boulder field due to relatively short boulder transport distances. The boulder-inferred 1953 tsunami flow velocity is estimated at over 9 m s(-1) at the reef edge. Subsequent events, for example Cyclone Kina (1993), appear to have remobilised some large boulders. While prior research has demonstrated headward retreat of Suva Canyon in response to the repeated occurrence of earthquakes over the past few millennia, our results highlight the lingering vulnerability of the Fijian coastlines to high-energy waves generated both in the presence (tsunami) and absence (storm) of submarine failures and/or earthquakes. To explain the age discrepancies of U-Th dated coral comprising the deposited boulders, we introduce a conceptual model showing the role of repeated episodes of tsunamigenic submarine landslides in removing reef front sections through collapse. Subsequent high-energy wave events transport boulders from exposed older sections of the reef front onto the reef where they are deposited as 'new' boulders, alongside freshly detached sections of the living reef. In similar situations where anachronistic deposits complicate the deposition signal, age-dating of the coral boulders should not be used as a proxy for determining the timing of the submarine landslides or the tsunamis that generated them. (C) 2017 Elsevier B.V. All rights reserved.

Surface enhanced Raman spectroscopy (SERS) provides highly specific vibrational signatures identifying dried blood for a variety of forensic applications. SERS spectra on Au nanoparticle substrates excited at 785 nm are found to identify dried stains of human and nonhuman blood from seven animals, and distinguish stains due to menstrual and peripheral blood. In addition, the unique SERS bloodstain spectrum is distinct from the SERS spectra of thirty red-brown stains of potential household substances that could be visually mistaken for bloodstains and from food stains that have been shown to give positive results with presumptive colorimetric blood tests. Finally, a SERS swab procedure has been developed and demonstrates that the substrates that a blood sample dried on does not offer any Raman or fluorescence interference for the SERS identification of dried blood. Such bloodstains on porous and nonporous materials are all identical and exclusively due to the heme moiety of hemoglobin. Optimized selection of the extraction solvent is found to control the chemical composition of molecular components appearing in the SERS spectrum of complex, multicomponent biological mixtures, such as body fluids.

Background Approximately 20% of ischemic strokes are associated with clinically apparent atrial fibrillation (AF). Regardless of stroke etiology, detection of AF in patients with ischemic strokes often changes antithrombotic treatment from anti-platelet to oral anticoagulation therapy. The role and the optimum duration of cardiac monitoring to detect AF in patients with strokes presumed due to large vessel atherosclerosis or small vessel disease is unknown. This manuscript describes the design and rationale of the STROKE-AF trial. Study design STROKE-AF is a randomized, controlled, open-label, post-market clinical trial. Detection of AF will be evaluated using continuous arrhythmia monitoring with an insertable cardiac monitor (ICM) compared with standard of care follow-up in patients with stroke (within the prior 10 days) that is presumed due to large vessel cervical or intracranial atherosclerosis, or to small vessel disease. Approximately 500 patients will be enrolled at approximately 40 centers in the United States. Patients will be randomized 1:1 to arrhythmia monitoring with an ICM (continuous monitoring arm) or standard of care follow-up (control arm). Subjects will be followed for ≥12 months and up to 3 years. Outcomes The primary objective is to compare the incidence rate of detected AF through 12 months of follow-up between the two arms. Conclusion This trial will provide information on the value of ICMs to detect subclinical AF in patients with stroke presumed due to large vessel atherosclerosis or small vessel disease, which will have implications for guiding treatment with oral anticoagulation for secondary stroke prevention.

From a review of 184 studies on bamboo biomass for 70 species (22 genera) we estimate plausible ranges for above-ground carbon (AGC) biomass (16–128 Mg C/ha), below-ground carbon (BGC) biomass (8–64 Mg C/ha), soil organic carbon (SOC; 70–200 Mg C/ha), and total ecosystem carbon (TEC; 94–392 Mg C/ha). The total ecosystem carbon range is below that for most types of forests, on par with that of rubber plantations and tree orchards, but greater than agroforests, oil palm, various types of swidden fallows, grasslands, shrublands, and pastures. High carbon biomass was associated with many Phyllostachys spp., including Moso (P. edulis) in China, Japan, Taiwan, and Korea, as well as other “giant” bamboo species of genera Bambusa, Dendrocalamus, Gigantochloa, and Guadua. The low end of the TEC range for mature bamboo typically included various species of dwarf bamboo, understory species, and stands stressed by climatic factors (temperature, rainfall), soil conditions, and management practices. Limited research and uncertainties associated with determinations prevent a robust assessment of carbon stocks for most species. Moso bamboo was by far the most studied species (>40% of the reported values), as it is commonly grown in plantations for commercial use. Similarly, a review of available allometric equations revealed that more work is needed to develop equations for predicting carbon biomass for most species. Most allometry equations exist for AGC for China, where 33 species have been studied. Allometric equations for BGC are rare, with all work conducted in China (15 species) and India (2). Root:shoot ratio estimate for most groups of species and genera were less than one, with the exception of Phyllostachys spp (however, some individual species with small sample size were greater than one). Estimated annual carbon accumulation rates were on the order of 8–14 Mg C/ha, relaxing to ≤4 Mg C/ha after selective harvesting of stands commences following maturation–but the timing of this rate change could not be reliably ascertained. The high standing carbon stocks and high annual accumulation rates point to the possibility of successful carbon farming using bamboo, if stands are managed efficiently (sufficient water, adequate nutrients, appropriate thinning/harvesting). Key in long-term carbon sequestration of bamboo is making sure harvested bamboo are turned into durable products (e.g., permanent construction materials, furniture, art). While our review demonstrated the potential of bamboo as an efficient and effective carbon sink, further research is needed to reduce uncertainties in the underlying data, resulting from a lack of standardization of methods, a lack of research for many bamboo species, and limited research of below-ground and soil organic carbon. Another priority is obtaining more carbon estimates for under-represented regions such as Central America, South America and Africa. Finally, we conducted a case study in northern Thailand that demonstrated the difficulty in sampling above- and below-ground components of total ecosystem carbon, as well as the threat of drastic bamboo biomass loss associated with instances of gregarious flowering. Overall, we recommend that instead of being seen as an invasive species with low utility, bamboo should be given greater recognition in policy and management for its value as a carbon sink, critical in mitigating the effects of climate change, and for its ability to provide key ecosystem services for humans, such as stabilizing hillslopes from accelerated soil erosion, improving soil fertility, and providing food and construction materials.

We use paleoflood deposits to reconstruct a record of past floods for the Alaknanda-Mandakini Rivers (Garhwal Himalaya), the Indus River (Ladakh, NW Himalaya) and the Brahmaputra River (NE Himalaya). The deposits are characterized by sand-silt couplets, massive sand beds, and from debris flow sediment. The chronology of paleoflood deposits, established by Optically Stimulated Luminescence (OSL) and C-14 AMS dating techniques, indicates the following: (i) The Alaknanda-Mandakini Rivers experienced large floods during the wet and warm Medieval Climate Anomaly (MCA); (ii) the Indus River experienced at least 14 large floods during the Holocene climatic optimum, when flood discharges were likely an order of magnitude higher than those of modern floods; and (iii) the Brahmaputra River experienced a megaflood between 8 and 6 ka. Magnetic susceptibility of flood sediments indicates that 10 out of 14 floods on the Indus River originated in the catchments draining the Ladakh Batholith, indicating the potential role of glacial lake outbursts (GLOFs) and/or landslide lake outbursts (LLOFs) in compounding flood magnitudes. Pollen recovered from debris flow deposits located in the headwaters of the Mandakini River showed the presence of warmth-loving trees and marshy taxa, thereby corroborating the finding that floods occurred during relatively warm periods. Collectively, our new data indicate that floods in the Himalaya largely occur during warm and wet climatic phases. Further, the evidence supports the notion that the Indian Summer Monsoon front may have penetrated into the Ladakh area during the Holocene climatic optimum. (C) 2016 Elsevier B.V. All rights reserved.

This white paper, prepared by members of the Cardiac Safety Research Consortium (CSRC), discusses important issues regarding scientific and clinical aspects of long-term electrocardiographic safety monitoring during clinical drug development. To promote multistakeholder discussion of this topic, a Cardiac Safety Research Consortium-sponsored Think Tank was held on 2 December 2015 at the American College of Cardiology's Heart House in Washington, DC. The goal of the Think Tank was to explore how and under what circumstances new and evolving ambulatory monitoring technologies could be used to improve and streamline drug development. This paper provides a detailed summary of discussions at the Think Tank: it does not represent regulatory guidance.

Accurate estimation of the magnitude and spatio-temporal variability of rainfall in the Indian Himalaya is difficult because of the sparse and limited network of ground stations located within complex terrain, as well as the difficulty of maintaining the stations over time. Thus, secondary rainfall sources are important to hydrological and hazard studies, if they reproduce the dynamics of rainfall satisfactorily. In this work, we evaluate four secondary products in the Garhwal Himalaya in India, with a focus on their application within the Mandakini River Catchment, the site of a devastating flood and multiple large landslides in 2013. The analysis included two satellite products: from the Tropical Rainfall Measuring Mission (TRMM) and the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN) program, as well as two gridded products: the Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of Water Resources (APHRODITE) product and the India Meteorological Department (IMD) product. In comparing the four products against data collected at four ground stations (Rudraprayag, Joshimath, Purola, and Mukhim) using a variety of statistical indices, we determined that the IMD and TRMM products were superior to the others. In particular, the IMD product ranked the best for most indices including probability of detection (POD), false alarm ratio (FAR), receiver operating curve (ROC), and root mean squared error (RMSE). The TRMM product performed satisfactorily in terms of bias and detecting daily maximum monsoon rainfall at three of the four stations. The APHRODITE product had POD, FAR and ROC values that were among the best at higher rainfall depths at the Mukhim station. The PERSIANN product generally did not perform well based on these indices, consistently underestimating station rainfall depths. Finally, the IMD product could document the daily rainfall distribution during the June 2013 flood in the Mandakini Catchment and adjoining places.

Our assessment of 30 water bodies in the vicinity of the Mae Moh coal mine and power station in northern Thailand does not indicate substantial water quality management challenges to developing fisheries/aquaculture in peripheral reservoirs and streams. Negative water quality issues such as high concentrations of arsenic (2-17 μg/L) and ions including sulfate (868-2605 mg/L), sodium (217-552 mg/L), and total ammonia (1-5 mg/L) were associated with groundwater and surface water resources on the facility, as well as the stream network draining from it. Total dissolved solids were also very high, ranging from 658 to 3610 mg/L. Six of seven ponds tested had As concentrations in the range of 5-17 μg/L. Although these levels are less than the Thai regulation for industrial effluent, they are elevated over background surface water concentrations. The highest concentration in a contaminated stream was 10.54 μg/L As, which is only slightly above the WHO (2017) regulation of 10 μg/L for drinking water. Ponds, contaminated streams, and deep subsurface water should not be used for fisheries/aquaculture without extensive remediation/treatment. Concentrations of these water parameters in peripheral streams and reservoirs were not of environmental concern. High water hardness (161-397 mg/L CaCO

Many islands throughout SE Asia are experiencing rapid development and land-cover conversion that potentially threaten sensitive coastal ecosystems, such as seagrasses, through increased loading of sediment and nutrients originating from disturbed catchments draining to the sea. To evaluate this threat for one such island in Southern Thailand (Yao Yai), we perform sediment source tracing via end-member mixing analysis using stable isotopes δ 13 C and δ 15 N in organic matter to explore sediment loading in a seagrass meadow. The analysis indicates that sedimentary material in the meadow originates mostly from ocean-associated sources (∼62% from seagrass detritus, seston, and ocean sediments). Terrestrial material comprises ∼19% of the organic material found in the seagrass meadow, with another 20% originating from an adjacent mangrove forest. Approximately one-fourth of the seagrass meadow material (24%) is detritus that has been (re)deposited internally. The high contribution of terrestrial-derived organic matter deposited near the river mouth demonstrates that substantial quantities of sediment are being transferred from upslope erosion sources into the seagrass meadow. However, only a small amount of this material is deposited throughout the entire bay because much of the terrestrial- and mangrove-derived sediment is transferred to the open ocean via channels that are periodically dredged to allow boat access to two small inland harbours. This positive affect of dredging has not received very much attention in existing literature. River water flowing to the channels during falling tide delivers sediment to these efficient pathways, where much of it bypasses the seagrass meadow at periods of time when sediment deposition would normally be the greatest. There is growing concern that ongoing land-cover changes and planned urbanization related to tourism and agriculture on the island may boost sediment/nutrients above a critical threshold, beyond that revealed in our baseline survey. Our tracer-based sediment source approach did not corroborate our observations of substantial erosion and land degradation in the upper catchment—but this could be a result of sediment flushing through the dredged channels. We encourage others to combine such methods with sediment budgeting approaches to triangulate results for consistency. Finally, from an ecological perspective, the high presence of seagrass detritus we found in bay sediments suggests seagrass is potentially a key source of nutrients for the meadow itself, as well as other connected ecosystems.

A catchment-scale investigation of the prevalence of Cryptosporidium and Giardia in the Kuang River Basin was carried out during the dry and rainy seasons. Water samples were collected from the Kuang River and its tributaries as well as a major irrigation canal at the study site. We also investigated the prevalence of gastrointestinal parasitic infection among dairy and beef cattle hosts. Cryptosporidium and/or Giardia were detected in all the rivers considered for this study, reflecting their ubiquity within the Kuang River Basin. The high prevalence of Cryptosporidium/Giardia in the upper Kuang River and Lai River is of a particular concern as both drain into the Mae Kuang Reservoir, a vital source of drinking-water to many local towns and villages at the research area. We did not, however, detected neither Cryptosporidium nor Giardia were in the irrigation canal. The frequency of Cryptosporidium/Giardia detection nearly doubled during the rainy season compared to the dry season, highlighting the importance of water as an agent of transport. In addition to the overland transport of these protozoa from their land sources (e.g. cattle manure, cess pits), Cryptosporidium/Giardia may also be re-suspended from the streambeds (a potentially important repository) into the water column of rivers during storm events. Faecal samples from dairy and beef cattle showed high infection rates from various intestinal parasites - 97% and 94%, respectively. However, Cryptosporidium and Giardia were only detected in beef cattle. The difference in management style between beef (freeranging) and dairy cattle (confined) may account for this disparity. Finally, phylogenetic analyses revealed that the Cryptosporidium/Giardia-positive samples contained C. ryanae (non-zoonotic) as well as Giardia intestinalis assemblages B (zoonotic) and E (non-zoonotic). With only basic water treatment facilities afforded to them, the communities of the rural area relying on these water supplies are highly at risk to Cryptosporidium/Giardia infections.

In Northern Thailand, incidences of fluorosis resulting from the consumption of high-fluoride drinking-water have been documented. In this study, we mapped the high-fluoride endemic areas and described the relevant transport processes of fluoride in enriched waters in the provinces of Chiang Mai and Lamphun. Over one thousand surface and sub-surface water samples including a total of 995 collected from shallow (depth: ≤ 30 m) and deep (> 30 m) wells were analysed from two unconnected high-fluoride endemic areas. At the Chiang Mai site, 31% of the shallow wells contained hazardous levels (≥ 1.5 mg/L) of fluoride, compared with the 18% observed in the deep wells. However, at the Lamphun site, more deep wells (35%) contained water with at least 1.5mg/L fluoride compared with the shallow wells (7%). At the Chiang Mai site, the high-fluoride waters originate from a nearby geothermal field. Fluoride-rich geothermal waters are distributed across the area following natural hydrological pathways of surface and sub-surface water flow. At the Lamphun site, a well-defined, curvilinear high-fluoride anomalous zone, resembling that of the nearby conspicuous Mae Tha Fault, was identified. This similarity provides evidence of the existence of an unmapped, blind fault as well as its likely association to a geogenic source (biotite-granite) of fluoride related to the faulted zone. Excessive abstraction of ground water resources may also have affected the distribution and concentration of fluoride at both sites. The distribution of these high-fluoride waters is influenced by a myriad of complex natural and anthropogenic processes which thus created a challenge for the management of water resources for safe consumption in affected areas. The notion of clean and safe drinking water can be found in deeper aquifers is not necessarily true. Groundwater at any depth should always be tested before the construction of wells.

Our review of biomass studies conducted for 11 Southeast Asian countries, Papua New Guinea, and southern China uncovered 402 above-ground and 138 below-ground biomass allometric equations for the following major land covers: forest, peat swamp forest, mangrove forest, logged over forest, orchard and tree plantation, rubber plantation, oil palm plantation, bamboo, swidden fallow, and grassland/pasture/shrub land. No equations existed for non-swidden agroforest and permanent croplands, two other important land covers involved in current and projected land-cover transitions. We also found 245 stem-volume equations and 50 height-diameter equations. Applying existing allometric equations out of convenience is potentially a key source of uncertainty in above- and below-ground carbon stock estimates in many SE Asian landscapes. Differences in environmental conditions and vegetation characteristics should preclude the use of many pre-existing equations at locations outside of the geographical location where they were developed, without first verifying their applicability. While use of site-specific equations is preferred to reduce uncertainty in estimates, there are few in existence for many land covers and many geographical areas of the region. For example, few or no equations exist for Brunei, Cambodia, Laos, Papua New Guinea, Singapore, and Timor Leste. Ten or fewer above-ground biomass equations exist for rubber plantation, oil palm plantation, non-swidden agroforest, grassland/pasture/shrublands, and permanent croplands for the entire region. Even site-specific equations can introduce uncertainties to biomass estimates if they were determined from an insufficient sample size. Difficulties associated with sampling below-ground root biomass accurately often leads to allometric equations that potentially under-estimate below-ground biomass. In addition, substantial errors may be present if these below-ground equations are conveniently used by researchers in lieu of site-specific measurements. Although the importance of including wood density in allometry is increasingly recognized, only 26 of the reviewed studies did so. Ideally, when wood density values are used to estimate biomass, new on-site measurements should be taken, rather than relying on pre-existing values. This review demonstrates that more research in SE Asia is needed on biomass in general, specifically for several land covers including peat swamp forest, rubber and oil palm plantations, bamboo, swidden fallow, non-swidden agroforest, and permanent cropland. Importantly, for the purpose of informing the development and implementation of policies and programs such as REDD+, our meta-analysis highlights the pressing need to address the insufficient number of allometric equations and the possible inappropriate use of some when estimating vegetation biomass related to current and potential land cover changes in the region.

Delineating the characteristics of biosphere-atmosphere exchange in rubber (Hevea brasiliensis Mull. Arg.) plantations, which are rapidly expanding throughout mainland Southeast Asia, is important to understanding the impacts of the land-use change on environmental processes. In attempt to shed new light on the impacts of conversion to rubber, we have conducted eddy flux measurements over a 3-year period in two rubber plantation sites: (1) Som Sanuk, located in northeastern Thailand; and (2) Cambodian Rubber Research Institute (CRRI), located in central Cambodia. Both sites have a distinct dry season. We used a combination of actual evapotranspiration (ET) flux measurements and an inverted version of a simple 2-layer ET model for estimating the mean canopy stomatal conductance (gs). The potential water balance (precipitation (P) − potential evaporation (ET_POT)) for each season (i.e., December–February: DJF, March–May: MAM, June–August: JJA, and September–November: SON) revealed when and how the water use is controlled. In the seasons when actual water balance (P − ET) was negative (DJF and MAM), the deficit was compensated with soil water from the previous season at depths of 0–2 m (Thailand site) and 0–3 m (Cambodia site). At both sites, the reference value of gs (gsref) and the sensitivity of gs to atmospheric demand (m) appeared to be less in DJF and MAM than each in the other two 3-month periods (seasons). On average, in a whole year, m/gsref was less in Thailand (

The first decade of the new millennium saw a boom in rubber prices. This led to rapid and widespread land conversion to monoculture rubber plantations in continental SE Asia, where natural rubber production has increased >50% since 2000. Here, we analyze the subsequent spread of rubber between 2005 and 2010 in combination with environmental data and reports on rubber plantation performance. We show that rubber has been planted into increasingly sub-optimal environments. Currently, 72% of plantation area is in environmentally marginal zones where reduced yields are likely. An estimated 57% of the area is susceptible to insufficient water availability, erosion, frost, or wind damage, all of which may make long-term rubber production unsustainable. In 2013 typhoons destroyed plantations worth US$ >250 million in Vietnam alone, and future climate change is likely to lead to a net exacerbation of environmental marginality for both current and predicted future rubber plantation area. New rubber plantations are also frequently placed on lands that are important for biodiversity conservation and ecological functions. For example, between 2005 and 2010 >2500 km(2) of natural tree cover and 610 km(2) of protected areas were converted to plantations. Overall, expansion into marginal areas creates potential for loss-loss scenarios: clearing of high-biodiversity value land for economically unsustainable plantations that are poorly adapted to local conditions and alter landscape functions (e.g. hydrology, erosion) - ultimately compromising livelihoods, particularly when rubber prices fall. (C) 2015 Elsevier Ltd. All rights reserved.

Now more than ever postgraduate students in geography are expected to publish their research before they graduate. This work often occurs with their supervisors. We write this essay as a guide for students on the collaborative supervisor–postgraduate publishing relationship. We explore three aspects of the relationship where misunderstanding or miscommunication often occur: expectations arising during writing and publishing, the writing process itself, and fluctuating levels of supervisor engagement through the student’s postgraduate period. Our intention in highlighting these themes is to help both supervisors and postgraduates engage in productive and collaborative writing.

article This paper reviews the current state of knowledge regarding bedload transport in SE Asian streams and presents the results from a case study on bedload transport in a mountain stream in northern Thailand. Together, the review and new data help contextualize the paucity of work done in the region in the face of a rapid increase in development and reservoir building throughout SE Asia. Data from both the reviewed studies and the case study indicate that bedload transport in many SE Asian streams (e.g. catchment areas b 100 km 2 )i s often much higherthan iscommonly assumed for tropicalstreams(i.e.,about 10% of the totalsediment load). Estimat- ed annual bedload proportion was 18% of the total annual sediment load in the 74-km

Summary Annual total suspended solid (TSS) loads in the Mae Sa Catchment in northern Thailand, determined with an automated, turbidity-based monitoring approach, were approximately 62,000, 33,000, and 14,000 Mg during the three years of observation. These loads were equivalent to basin yields of 839 (603–1170), 445 (217–462), and 192 (108–222) Mg km−2 for the 74.16-km2 catchment during 2006, 2007, and 2008, respectively. The yearly uncertainty ranges indicate our loads may be underestimated by 38–43% or overestimated by 28–33%. In determining the annual loads, discharge (Q) and turbidity (T) values were compared against 333 hand-sampled total suspended solid concentrations (TSS) measured during 18 runoff events and other flow conditions across the three-year period. Annual rainfall varied from 1632 to 1934 mm; and catchment runoff coefficients (annual runoff/annual rainfall) ranged from 0.25 to 0.41. Measured TSS ranged from 8 to 15,900 mg l−1; the low value was associated with dry-season base flow; the latter, a wet-season storm. Storm size and location played an important role in producing clockwise, anticlockwise, and complex hysteresis in the Q-TSS relationship. Turbidity alone was a good estimator for turbidity ranges of roughly 10–2800 NTU (or concentrations approximately 25–4000 mg l−1). However, owing to hysteresis and high sediment concentrations that surpass the detection limits of the turbidity sensor during many annual storms, TSS was estimated best using a complex multiple regression equation based on high/low ranges of turbidity and Q as independent variables. Turbidity was not a good predictor of TSS fractions >2000 μm. Hysteresis in the monthly Q-TSS relationship was generally clockwise over the course of the monsoon season, but infrequent large dry-season storms disrupted the pattern in some years. The large decrease in annual loads during the study was believed to be related to depletion of fine sediment delivered to the stream by several landslides occurring the year prior to the study. The study indicated the importance of monitoring Q and turbidity at fine resolutions (e.g., sub-hourly) to capture the TSS dynamics and to make accurate load estimations in this flashy headwater stream where hysteresis in the Q-TSS signature varied at several time scales.

Objectives This study aimed to identify how accurately the current clinical atrial fibrillation (AF) classifications reflect its temporal persistence. Background Clinical classification of AF is employed to communicate its persistence, to select appropriate therapies, and as inclusion criterion for clinical trials. Methods Cardiac rhythm histories of 1,195 patients (age 73.0 ± 10.1 years, follow-up: 349 ± 40 days) with implantable devices were reconstructed and analyzed. Patients were classified as having paroxysmal or persistent AF by physicians at baseline in accordance with current guidelines. AF burden, measured as the proportion of time spent in AF, was obtained from the device. Additionally we evaluated the agreement between clinical and device-derived AF classifications. Results Patients within the same clinical class were highly heterogeneous with regards to AF temporal persistence. Agreement between the clinical AF classification and the objective device-derived assessments of AF temporal persistence was poor (Cohen's kappa: 0.12 [95% CI: 0.05 to 0.18]). Patient characteristics influenced the clinical decision to classify AF as paroxysmal or persistent. Higher ejection fraction (odds ratio: 0.97/per unit [95% CI: 0.95 to 0.98/per unit]; p < 0.0001) and presence of coronary artery disease (odds ratio: 0.53 [95% CI: 0.32 to 0.88]; p = 0.01) were independently associated with a lower probability of being classified as persistent AF for the same AF burden level. Conclusions The currently used clinical AF classifications poorly reflect AF temporal persistence. Patient characteristics significantly influence the physician's classification of AF. Patients classified in identical clinical categories may be inherently heterogeneous with regard to AF temporal persistence. Further study is required to determine if patient selection on the basis of objective criteria derived from rigorous AF monitoring can improve reported outcomes and better identify responders and non-responders to treatments. (OMNI Study–Assessing Therapies in Medtronic Pacemaker, Defibrillator, and Cardiac Resynchronization Therapy Devices; [NCT00277524][1]; TRENDS: A Prospective Study of the Clinical Significance of Atrial Arrhythmias Detected by Implanted Device Diagnostics; [NCT00279981][2]) [1]: http://www.clinicaltrials.gov/ct2/show/NCT00277524?term=NCT00277524%26rank=1 [2]: http://www.clinicaltrials.gov/ct2/show/NCT00279981?term=NCT00279981%26rank=1

There are no clearly-defined thresholds of device-detected atrial fibrillation (DDAF) burden for which to initiate oral anticoagulation (OAC). We performed a retrospective cohort study using data from the national Veterans Health Administration health care system linked to remote monitoring (RM)

Myanmar is a country of huge biodiversity importance that is undergoing major political change, bringing with it new international engagement. This includes access to international markets, which will likely spur investment in export-oriented agriculture, leading to increased pressures on already threatened ecosystems. This scenario is illustrated in the Ayeyarwady Delta, the country's agricultural heartland sustaining high deforestation rates. Using the Delta as a model system, we use an integrated approach to inquire about whether and how imminent agricultural reforms associated with an internationally-engaged Myanmar could introduce new actors and incentives to invest in agricultural expansion that could affect deforestation rates. We use a novel remote sensing analysis to quantify deforestation rates for the Delta from 1978 to 2011, develop business-as-usual deforestation scenarios, and contextualize those results with an analysis of contemporary policy changes within Myanmar that are expected to alter the principal drivers of land-cover change. We show that mangrove systems of Myanmar are under greater threat than previously recognized, and that agriculture has been the principle driver of deforestation on the Delta. The centrality of agriculture to the Myanmar economy indicates that emerging policies are likely to tip the scales towards agricultural expansion, agro-industrial investment and potentially greater rates of deforestation due to the introduction of well-funded investors, insufficient land tenure agreements, and low governance effectiveness. The broad national challenge is to initiate environmental governance reforms (including safeguards) in the face of significant pressures for land grabbing and opportunistic resource extraction.

Mangroves play a disproportionately large role in carbon sequestration relative to other tropical forest ecosystems. Accurate assessments of mangrove biomass at the site-scale are lacking, especially in mainland Southeast Asia. This study assessed tree biomass and species diversity within a 151 ha mangrove ecosystem on the Andaman Coast of Thailand. High-resolution GeoEye-1 satellite imagery, medium resolution ASTER satellite elevation data, field-based tree measurements, published allometric biomass equations, and a suite of machine learning techniques were used to develop spatial models of mangrove biomass. Field measurements derived a whole-site tree density of 1313 trees ha � 1 , with Rhi- zophora spp. comprising 77.7% of the trees across forty-five 400 m 2 sample plots. A support vector machine regression model was found to be most accurate by cross-validation for predicting biomass at the site level. Model-estimated above-ground biomass was 250 Mg ha � 1 ; below-ground root biomass was 95 Mg ha � 1 . Combined above-ground and below-ground biomass for the entire 151-ha stand was 345 (� 72.5) Mg ha � 1 , equivalent to 155 (� 32.6) Mg C ha � 1 . Model evaluation shows the model had

Owing to difficulties associated with measuring root biomass accurately in space and time, below-ground root biomass is often calculated indirectly from above-ground biomass measurements via general allometric equations. Of concern is that general equations may not provide accurate site-specific calculations for accurate carbon stock assessments. This review comparing more than 100 root-related studies conducted in SE Asia shows highly variable and uncertain below-ground woody carbon (BGC) biomass estimates for many vegetation types associated with on-going land-use changes throughout the region. Most BGC data exist for Indonesia, Malaysia, and Thailand; only a few studies have been conducted for Brunei, Cambodia, Lao PDR, Myanmar, Papua New Guinea, Philippines, Singapore, Timor Leste and Vietnam. While substantial data exist for a variety of forests and timber-plantations, little work has focused on key transition land-covers including rubber, oil palm, swidden fallows, agroforests, grasslands, and croplands. Mangroves (12–219 Mg C ha−1), peat forests (11–71 Mg C ha–1) and other forest types (11–74 Mg C ha–1) have the highest BGC values. The limited data for rubber plantations (5–32 Mg C ha–1), oil palm plantations (4–22 Mg C ha–1), swidden fallows (3–16 Mg C ha−1), and non-swidden agroforestry (3–16 Mg C ha−1) indicate modest differences in the amount of BGC for several land covers that are at the heart of ongoing debates regarding the human and environmental impacts of agricultural intensification. The paucity of data currently in existence for the region highlights the need for additional field investigations—following accepted protocols—of root biomass to facilitate efforts to improve carbon stock estimates. Government agencies, private enterprises, and development agencies could help lead the way in developing a better forest carbon database by teaming with researchers to assess total ecosystem carbon stocks prior to vegetation being removed for construction, mining, or stand rotations.

a b s t r a c t We developed a soil-vegetation-atmosphere transfer (SVAT) model applicable to simulating CO2 and H2O fluxes from the canopies of rubber plantations, which are characterized by distinct canopy clumping produced by regular spacing of plantation trees. Rubber (Hevea brasiliensis Mull. Arg.) plantations, which are rapidly expanding into both climatically optimal and sub-optimal environments throughout main- land Southeast Asia, potentially change the partitioning of water, energy, and carbon at multiple scales, compared with traditional land covers that are being replaced. Describing the biosphere-atmosphere exchange in rubber plantations via SVAT modeling is, therefore, important to understanding the impacts on environmental processes. The regular spacing of plantation trees creates a peculiar canopy structure that is not well represented in most SVAT models, which generally assume a non-uniform spacing of vegetation. Herein we develop a SVAT model applicable to a rubber plantation and an evaluation method for its canopy structure, and examine how the peculiar canopy structure of rubber plantations affects canopy CO2 and H2O exchanges. Model results are compared with measurements collected at a field site in central Cambodia. Our findings suggest that it is crucial to account for intensive canopy clumping in order to reproduce observed rubber plantation fluxes. These results suggest a potentially optimal spacing of rubber trees to produce high primary productivity and water use efficiency.

The failure of a LP (low pressure) turbine blade of a 310 MW thermal power plant is presented. The fracture took place at the aerofoil region, 150 mm from the root. Several pits were found on the edges of the blades and chloride was detected in these pits. They were responsible for the crevice type corrosion. The failure mode was intergranular type. The blade material matches the composition of X20Cr13 steel; however, the hardness shows high values (between 450 and 480 BHN) compared to standard values of 270–300 BHN.

This work quantifies commuter exposure to black carbon, CO and noise when waiting for and travelling in the mass transport khlong (canal) boats in Bangkok, Thailand. Exposure to toxic pollutants and acute noise is similar or worse than for other transportation modes. Mean black carbon concentrations observed at one busy pier and along the main canal were much higher than ambient concentrations at sites impacted by vehicular traffic. Concentrations of CO were similar to those reported for roadside areas of Bangkok. The equivalent continuous sound levels registered at the landing pier were similar to those reported for roadsides, but values recorded inside the boats were significantly higher.

The detection of undiagnosed atrial tachycardia/atrial fibrillation (AT/AF) among patients with stroke risk factors could be useful for primary stroke prevention. We analyzed newly detected AT/AF (NDAF) using continuous monitoring in patients with stroke risk factors but without previous stroke or evidence of AT/AF. NDAF (AT/AF5 minutes on any day) was determined in patients with implantable cardiac rhythm devices and ≥1 stroke risk factors (congestive heart failure, hypertension, age ≥75 years, or diabetes). All devices were capable of continuously monitoring the daily cumulative time in AT/AF. Of 1,368 eligible patients, NDAF was identified in 416 (30%) during a follow-up of 1.1 ± 0.7 years and was unrelated to the CHADS(2) score (congestive heart failure, hypertension [blood pressure consistently140/90 mm Hg or hypertension treated with medication], age ≥75 years, diabetes mellitus, previous stroke or transient ischemic attack). The presence of AT/AF6 hours on ≥1 day increased significantly with increased CHADS(2) scores and was present in 158 (54%) of 294 patients with NDAF and a CHADS(2) score of ≥2. NDAF was sporadic, and 78% of patients with a CHADS(2) score of ≥2 with NDAF experienced AT/AF on10% of the follow-up days. The median interval to NDAF detection in these higher risk patients was 72 days (interquartile range 13 to 177). In conclusion, continuous monitoring identified NDAF in 30% of patients with stroke risk factors. In patients with NDAF, AT/AF occurred sporadically, highlighting the difficulty in detecting paroxysmal AT/AF using traditional monitoring methods. However, AT/AF also persisted for6 hours on ≥1 days in most patients with NDAF and multiple stroke risk factors. Whether patients with CHADS(2) risk factors but without a history of AF might benefit from implantable monitors for the selection and administration of anticoagulation for primary stroke prevention merits additional investigation.

Summary Rivers have been under sampled to investigate carbon degassing, especially in the tropical and sub-tropical regions. An unprecedented high-temporal-resolution (daily) sampling during July 2008–August 2009 was conducted in the Longchuan River of the upper Yangtze basin, a subtropical monsoon river in China, to reveal the daily-to-seasonal dynamics of the partial pressure of CO2 (pCO2) and CO2 degassing flux from the river using Henry’s constant and CO2SYS. The pCO2 levels ranged from 230 to 8300 μatm with an average of 1230 μatm and obvious daily and seasonal variations. More than 92% samples were supersaturated with CO2 in contrast to the atmospheric equilibrium (380 μatm). pCO2 values in the river water in the wet season were relatively low, except in the flooding event in November, due to a dilution effect by heavy rainfall. In contrast, the pCO2 levels in the dry season were much higher, due to lower pH resulted from anthropogenic activities. Net CO2 degassing and pCO2 were strongly correlated with dissolved nitrogen, but weakly with water temperature, dissolved inorganic carbon and water discharge, and uncorrelated with particulate nutrients and biogenic elements. The estimated water-to-air CO2 degassing flux in the Longchuan River was about 27 mol/m2/yr, with the upper limit of 50 mol/m2/yr. Our study also indicated that among the carbon remobilized from land to water, around 7% (2800 t C/yr) of the total carbon was emitted to the atmosphere, 42% (17,000 t C/yr) deposited in the river-reservoirs system and 51% (21,000 t C/yr) exported further downstream. High spatial and temporal resolution of estimates of CO2 emission from the world large rivers is required due to extremely heterogeneous catchment characteristics and anthropogenic activities in space and time.

Road deposited sediments (RDS) are a valuable environmental medium for characterizing contaminant levels in urban areas; and their associated potentially toxic elements (PTEs) can directly impact both human and aquatic health. In this study, RDS were collected from 15 co-located industrial and residential roads throughout Singapore to determine the effect of land use on contaminant levels. A second pilot study was designed to quantify the efficiency of road sweeping in removing different RDS grain size fractions from industrial and residential roads. The fine fraction (63 μm) of all RDSs was analyzed for over 40 elements. Eleven elements that reflect geogenic and anthropogenic sources were examined in detail (Al, Co, Cr, Cu, Fe, Ni, Pb, Sb, Sc, Si, and Zn). Industrial RDS had statistically higher concentrations of Co, Cr, Fe, and Ni than residential RDS. Potentially toxic elements Cu, Pb, Sb, and Zn were enriched10-fold at all locations compared to upper continental crust values. Concentrations of Cu, Pb and Zn exceeded aquatic sediment probable effect concentration levels, suggesting they could generate a toxic response in bottom-dwelling aquatic organisms. Traffic was equally heavy at both industrial and residential sites, but large trucks and machinery comprised a larger proportion of the traffic in the industrial areas. Traffic was not significantly correlated with the PTE (i.e., Cu, Pb, Sb and Zn) concentrations. Plausible anthropogenic contaminant sources include vehicles (e.g., brake and tire wear, vehicle emissions) and several industrial activities including metal works, oil processing, and waste incineration. Street sweeping was effective in removal of large organic debris and inorganic RDS, but it was ineffective in removing the geochemically important fraction, i.e.,125 μm.

This meta-analysis of land-cover transformations of the past 10–15 years in tropical forest-agriculture frontiers world-wide shows that swidden agriculture decreases in landscapes with access to local, national and international markets that encourage cattle production and cash cropping, including biofuels. Conservation policies and practices also accelerate changes in swidden by restricting forest clearing and encouraging commercial agriculture. However, swidden remains important in many frontier areas where farmers have unequal or insecure access to investment and market opportunities, or where multi-functionality of land uses has been preserved as a strategy to adapt to current ecological, economic and political circumstances. In some areas swidden remains important simply because intensification is not a viable choice, for example when population densities and/or food market demands are low. The transformation of swidden landscapes into more intensive land uses has generally increased household incomes, but has also led to negative effects on the social and human capital of local communities to varying degrees. From an environmental perspective, the transition from swidden to other land uses often contributes to permanent deforestation, loss of biodiversity, increased weed pressure, declines in soil fertility, and accelerated soil erosion. Our prognosis is that, despite the global trend towards land use intensification, in many areas swidden will remain part of rural landscapes as the safety component of diversified systems, particularly in response to risks and uncertainties associated with more intensive land use systems.

Opisthorchiasis, together with its associated cholangiocarcinoma, is one of the most important human parasitic diseases on continental Southeast Asia. A great deal of epidemiological data from humans is available on this disease, particularly from the northeast of Thailand, however, only limited information is available on those aspects of the life cycle relating to its Bithynia (Gastropoda) and cyprinid fish intermediate hosts. Here we review the information which is available on the Bithynia hosts of Opisthorchis viverrini. Only one major ecological study has been carried out at one site on a single species of Bithynia. We show not only that detailed ecological studies are required to clarify the epidemiology of opisthorchiasis, but also that the taxonomic status of the Bithynia species transmitting O. viverrini requires clarification.

Opisthorchis viverrini is one of the most common and medically important food-borne parasites in the Lower Mekong area of Southeast Asia. As we learn more about its ecology, pathology and epidemiology we see the need to consider more deeply the socio-cultural dynamics with which food-borne species complexes are associated. This paper argues that the Mekong region is characterized by strong livelihoods and life-style associations within wetland ecosystems, which are inseparable from human eating habits (“raw attitudes”). Within the fish-rice economies of the region there are many long-cherished food cultures based on eating raw, semi-cooked and fermented fish dishes, which are known to lead to opisthorchiasis, and potentially cholangiocarcinoma. This paper examines evidence from northeast Thailand showing that dedicated health outreach campaigns do help to reduce prevalence of opisthorchiasis over time. For disease prevention and health education approaches to be most effective, they must be sensitive to culture, livelihood economics, gender, and age. Further integrative, inter-disciplinary and international research must incorporate the complex dynamics of parasite ecology, human behavior, socio-economics, and public health awareness.