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This study utilised remote sensing data and ArcGIS 10.8 software to evaluate changes in land use and land cover (LULC) and their effects on land surface temperature (LST) in Hai Duong Province, Vietnam, from 1992 to 2022. Landsat satellite data were pre-processed and classified using supervised methods for the years 1992, 2010, and 2022. In 1992, vegetation cover accounted for 57.89% of land cover, increasing to 84.49% in 2010, but then decreasing again to 66.67% in 2022. In contrast, the built-up area consistently increased, from 2.88% in 1992 to 29.35% in 2022, as most of the barren land present in 1992 became built-up area in 2022. The LST values were calculated from the thermal bands for the years 1992, 2010, and 2022 and ranged from 16.09°C to 34.27°C, 17.04°C to 36.74°C, and 11.03°C to 28.44°C, respectively. In addition, the Normalized Difference Vegetation Index (NDVI) values were calculated using the near-infrared band and the red band, with values ranging from -0.40 to 0.70 over the study period. A linear regression analysis indicated a shift in the correlation between NDVI and LST from positive to negative. This study highlights the significant transformation that occurred in Hai Duong Province due to rapid population density increases, urban growth and infrastructure development, leading to a decline in greenery. These LULC changes can cause severe environmental damage. These research findings will assist policymakers in formulating management strategies and sustainable land-use plans to minimize potential harm and promote sustainable development in the area.

Deforestation in the tropics continues inexorably with severe implications for biodiversity conservation, climate regulation and ecosystem services. This study investigated variation in forest cover in Thua Thien Hue province, Vietnam, using the Landsat Thematic Mapper and Operational Land Imager satellite images over the period 1989–2021. Imageries were classified using the maximum likelihood classification technique for the years 1989, 2006, and 2021 and were evaluated for accuracy using the kappa coefficient for each year. Furthermore, forest cover losses and gains were evaluated using the Normalized Difference Vegetation Index and Soil Adjusted Vegetation Index, which were compared with the output of the supervised classification. Results showed that the forest cover of Thua Thien Hue province has drastically declined over the years. The forest cover, which was estimated at 68.88% (3461.46 km2) of the total land area in 1989, increased to 69.04% (3469.51 km2) in 2006 and subsequently decreased to 57.55% (2891.81 km2) in 2021. Severely reduced forest cover is often associated with the expansion of agriculture on the forest edge; other contributing factors include logging, illegal production land, and forest fires. Overall, our results show the necessity of forest management, rational land-use planning policy, and increased community awareness of conservation and sustainable development of forest resources in the study area in the future.

Sangmi Kim,1 Carolyn Martin,2 John White,2 Maureen Carlyle,2 Bonnie Bui,2 Shiyao Gao,1 Claudia A Salinas1 1Global Patient Safety Pharmacoepidemiology, Eli Lilly and Company, Indianapolis, IN, USA; 2Health Economics and Outcomes Research, Optum Life Sciences, Eden Prairie, MN, USACorrespondence: Claudia A Salinas, Global Patient Safety Pharmacoepidemiology, Eli Lilly and Company, Lilly Corporate Center, 893 Delaware St, Indianapolis, IN, 46285, USA, Tel +1 317 433 9188, Email claudia.salinas@lilly.comPurpose: Health insurance claims databases provide an opportunity to study uncommon events, such as venous thromboembolism (VTE), in large patient populations. This study evaluated case definitions for identifying VTE among patients treated for rheumatoid arthritis (RA) using International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes in claims data.Patients and Methods: Study participants were insured adults who received treatment for and had a diagnosis of RA between 2016 and 2020. After a 6-month covariate assessment window, patients were observed for ≥ 1 month until health plan disenrollment, occurrence of a presumptive VTE, or end of the study (12/31/2020). Presumptive VTEs were identified using predefined algorithms based on ICD-10-CM diagnosis codes, anticoagulant use, and care setting. Medical charts were abstracted to confirm the VTE diagnosis. Performance of primary and secondary (less stringent) algorithms was assessed by calculating the positive predictive value (PPV; primary and secondary objectives). Additionally, a linked electronic health record (EHR) claims database and abstracted provider notes were used as a novel alternative source to validate claims-based outcome definitions (exploratory objective).Results: A total of 155 charts identified with the primary VTE algorithm were abstracted. The majority of patients were female (73.5%), with mean (standard deviation) age 66.4 (10.7) years and Medicare insurance (80.6%). Obesity (46.8%), ever smoking (55.8%), and prior evidence of VTE (28.4%) were commonly reported in medical charts. The PPV for the primary VTE algorithm was 75.5% (117/155; 95% confidence interval [CI], 68.7%, 82.3%). A less stringent secondary algorithm had a PPV of 52.6% (40/76; 95% CI, 41.4%, 63.9%). Using an alternative EHR-linked claims database, the primary VTE algorithm PPV was lower, potentially due to the unavailability of relevant records for validation.Conclusion: Administrative claims data can be used to identify VTE among patients with RA in observational studies.Keywords: algorithm validation, rheumatoid arthritis, venous thromboembolism, positive predictive value, administrative claims data, ICD-10-CM

Forests are essential in regulating climate and protecting land resources from natural disasters. In Vietnam's Dak Nong province, forest cover has changed significantly between 1989 and 2021. This study applies remote sensing and geographic information systems (GIS) approaches to detect negative changes in forest cover as well as other land cover types. The maximum likelihood classification tool was used to classify Landsat images for the years 1989, 2001, 2011, and 2021, with post-classification accuracy evaluated through kappa coefficient statistics. The potential to based classification on Normalized Difference Vegetation Index (NDVI) and Soil Adjusted Vegetation Index (SAVI) to detect changes in forest cover compared with supervised classification was also evaluated. The land use and land cover change detection results show that the forest area decreased from 77.54% of the study area in 1989 to 33.97% in 2021, with a total forest loss of 2,953.48 km 2 and only 117.12 km 2 of newly planted forest during this period. Broadly, forest cover in the area has been severely reduced, often due to indiscriminate logging and expansion of agricultural land on the forest edge.

This study utilised remote sensing data and ArcGIS 10.8 software to evaluate changes in land use and land cover (LULC) and their effects on land surface temperature (LST) in Hai Duong Province, Vietnam, from 1992 to 2022. Landsat satellite data were pre-processed and classified using supervised methods for the years 1992, 2010, and 2022. In 1992, vegetation cover accounted for 57.89% of land cover, increasing to 84.49% in 2010, but then decreasing again to 66.67% in 2022. In contrast, the built-up area consistently increased, from 2.88% in 1992 to 29.35% in 2022, as most of the barren land present in 1992 became built-up area in 2022. The LST values were calculated from the thermal bands for the years 1992, 2010, and 2022 and ranged from 16.09°C to 34.27°C, 17.04°C to 36.74°C, and 11.03°C to 28.44°C, respectively. In addition, the Normalized Difference Vegetation Index (NDVI) values were calculated using the nearinfrared band and the red band, with values ranging from -0.40 to 0.70 over the study period. A linear regression analysis indicated a shift in the correlation between NDVI and LST from positive to negative. This study highlights the significant transformation that occurred in Hai Duong Province due to rapid population density increases, urban growth and infrastructure development, leading to a decline in greenery. These LULC changes can cause severe environmental damage. These research findings will assist policymakers in formulating management strategies and sustainable land-use plans to minimize potential harm and promote sustainable development in the area. [ABSTRACT FROM AUTHOR]

Deforestation in the tropics continues inexorably with severe implications for biodiversity conservation, climate regulation and ecosystem services. This study investigated variation in forest cover in Thua Thien Hue province, Vietnam, using the Landsat Thematic Mapper and Operational Land Imager satellite images over the period 1989-2021. Imageries were classified using the maximum likelihood classification technique for the years 1989, 2006, and 2021 and were evaluated for accuracy using the kappa coefficient for each year. Furthermore, forest cover losses and gains were evaluated using the Normalized Difference Vegetation Index and Soil Adjusted Vegetation Index, which were compared with the output of the supervised classification. Results showed that the forest cover of Thua Thien Hue province has drastically declined over the years. The forest cover, which was estimated at 68.88% (3461.46 km²) of the total land area in 1989, increased to 69.04% (3469.51 km²) in 2006 and subsequently decreased to 57.55% (2891.81 km²) in 2021. Severely reduced forest cover is often associated with the expansion of agriculture on the forest edge; other contributing factors include logging, illegal production land, and forest fires. Overall, our results show the necessity of forest management, rational land-use planning policy, and increased community awareness of conservation and sustainable development of forest resources in the study area in the future. [ABSTRACT FROM AUTHOR]

Pluchea eupatorioides Kurz, which belongs to the family Asteraceae, is known for its medicinal properties and has been traditionally used to treat various diseases. This study aimed to investigate the chemical composition of the essential oil extracted from the aerial parts of P. eupatorioides and evaluate its antimicrobial and antioxidant activities. The essential oil was isolated by hydrodistillation and analysed by gas chromatography/ mass spectrometry (GC/MS). Thirty-three volatile compounds were identified in P. eupatorioides essential oil, including β-caryophyllene (29.36%), 2,5-dimethoxy-p-cymene (18.41%), α-isocomene (15.74%), and caryophyllene oxide (9.77%) as the major compounds. The antimicrobial activity of P. eupatorioides essential oil was investigated using a broth microdilution assay to determine the minimum inhibitory concentration (MIC). The results indicated that P. eupatorioides essential oil demonstrated effectiveness against Staphylococcus aureus ATCC 25923 and Candida albicans ATCC 10231 with a MIC of 100 µg/mL. Moreover, the essential oil was also found to be effective against Bacillus cereus ATCC 14579 and Escherichia coli ATCC 25922, but with a slightly higher MIC of 200 µg/mL. Furthermore, the antioxidant activity of P. eupatorioides essential oil was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging assays. The IC50 values calculated using the DPPH and ABTS assays were 164.2 and 136.1 µg/mL, respectively. These findings demonstrate that the P. eupatorioides essential oil could be used as a potential source of antimicrobial and antioxidant agents for the food and pharmaceutical industries. This is the first report describing the chemical compositions, antimicrobial and antioxidant activities of P. eupatorioides essential oil. [ABSTRACT FROM AUTHOR]

This study is the first to investigate the chemical composition of essential oil and antioxidant activity of the essential oil and methanol extracts from the leaves of Knema globularia (Lam.) Warb. from Vietnam. According to gas chromatography and gas chromatography-mass spectrometry analysis, the major constituents of K. globularia essential oil were β-elemene (25.48%), α-copaene (17.05%), β-caryophyllene (9.37%), and α-humulene (8.42%). The antioxidant activity of the samples was determined using DPPH and ABTS methods. In both assays, the polar subfraction of the methanolic extract showed better antioxidative capacity than the nonpolar subfraction and the essential oil. In addition, the amounts of total phenol value in the polar subfraction and the nonpolar subfraction were determined to be 113.84 μg/mg and 47.52 μg/mg, respectively. The findings demonstrate that the essential oil and methanol extracts of K. globularia possess significant antioxidant activities and may be a new potential source of natural antioxidants. [ABSTRACT FROM AUTHOR]