Northern Thailand Research Articles

CARBON SEQUESTRATION FOR AGROSILVICULTURE AGROFORESTRY PRACTICES: PRELIMINARY RESULTS FROM THREE INVESTIGATED VILLAGES IN UTTARADIT PROVINCE, NORTHERN, THAILAND

ARTICLE HIGLIGHTS- Agroforestry boosts carbon storage, reducing greenhouse gas emissions significantly.- Diverse tree-based farming enhances biodiversity, soil health, and climate resilience.- Carbon sequestration in agroforestry supports sustainable agriculture and environmental balance.- Agroforestry practices mitigate climate change by storing carbon in trees and soil.- Combining trees with crops provides multiple ecological and economic benefits.ABSTRACTOne of the processes for compensating greenhouse gas emissions is atmospheric carbon removal and storage in the terrestrial biosphere. Agricultural systems to which trees are returned for careful management alongside crops and animals are thought to be substantial CO2 sinks. People are increasingly realizing the importance of agroforestry because it is good for the environment and farming. In this study, total carbon pools from the aboveground biomass carbon (ABGC), forest floor carbon (FFC), and soil organic carbon (SOC) were investigated and carbon storage data for some agroforestry practices native to Uttaradit in northern Thailand were analyzed. The role of these carbon pools in reducing CO2 concentrations in the atmosphere was also discussed. The results showed differences in the total carbon stock sourced from traditional agroforestry (TAF), applied agroforestry (AAF), and developed agroforestry (DAF). The total carbon store (ABGC + TFFC + SOC) of TAF, AAF, and DAF was 267.05 Mg C/ha, 226.48 Mg C/ha, and 324.70 Mg C/ha, respectively. SOC contributed 47.64%, 54.26%, and 44.81% and ABGC contributed 22.75%, 19.79%, and 23.90% to the total carbon stock in TAF, AAF, and DAF, respectively. The CO2 adsorption was 979.27 Mg CO2/ha, 830.50 Mg CO2/ha, and 1,190.6 Mg CO2/ha in TAF, AAF, and DAF, respectively. It is clear that agroforestry systems serve as carbon sinks in terrestrial ecosystems. Although the comparison of agroforestry practices and other land use types is important for carbon mitigation and the implementation of the “Land Use, Land Use Change, and Forestry” concept for CO2 sinks, it is also crucial to compare the potential of carbon sequestration in different CO2 pools.

A study of tourist behaviour for the development of Lanna wellness tourism in Thailand

ABSTRACT This investigation studies the behaviours of wellness tourists in Northern Thailand with a view to summarising their collective preferences and expectations and addressing a significant gap in research on Thai wellness tourism. This will enable tourism businesses to begin tailoring their offerings to meet the specific needs of this market segment. 643 foreign tourists in Northern Thailand responded to a questionnaire concerning their motivations and preferences for wellness tourism activities. The findings reveal that there are clear differences between the behaviours of different nationalities that can be used to inform wellness tourism development in Thailand. This research uniquely contributes to literature in the field of wellness tourism by identifying and analysing the specific preferences and expectations of international wellness tourists in Northern Thailand, a previously underexplored demographic in the context of regional wellness tourism studies. Furthermore, it introduces a comparative analysis of national differences in wellness tourism behaviours, offering insights that can directly influence the strategic development of localised wellness tourism offerings.

Actinomycetospora aeridis sp. nov., Actinomycetospora flava sp. nov. and Actinomycetospora aurantiaca sp. nov., endophytic actinobacteria isolated from wild orchid (Aerides multiflora Roxb).

Three novel mycelium-forming actinobacteria, designated OC33-EN06T, OC33-EN07T, and OC33-EN08T, were isolated from wild orchid (Aerides multiflora Roxb), collected from a hill evergreen forest in Northern Thailand. Strains OC33-EN06T and OC33-EN07T showed the highest 16S rRNA gene similarity with Actinomycetospora lutea TT00-04T, 99.17 and 99.45%, respectively. Strain OC33-EN08T showed high similarity with four species, namely 'Actinomycetospora termitidis Odt1-22T' (99.37%), Actinomycetospora chiangmaiensis DSM 45062T (99.02%), Actinomycetospora corticicola 014-5T (99.02%), and Actinomycetospora soli SF1T (98.81%). Comparative genome analysis of OC33-EN06T, OC33-EN07T, and OC33-EN08T with the closely related type strains showed that average nucleotide identity (ANI) based on blast, ANI based on MUMmer, and average amino acid identity values were less than 95% and the digital DNA-DNA hybridization values were less than 70%, all below the thresholds for species demarcation. The digital G+C content of OC33-EN06T, OC33-EN07T, and OC33-EN08T were 74.5, 74, and 74 mol%, respectively. These three strains developed bud-like chains of non-motile cylindrical spores with a smooth surface. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The whole-cell sugars contained ribose, arabinose, and galactose. The predominant menaquinone was MK-8(H4). The phospholipid profile included phosphatidylcholine, phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylinositol. Based on comparative analysis of genotypic, phenotypic and chemotaxonomic data, strains OC33-EN06T (=TBRC 18349T=NBRC 116543T), OC33-EN07T (=TBRC 18350T=NBRC 116544T), and OC33-EN08T (=TBRC 18318T=NBRC 116542T) represent the type strains of three novel species of the genus Actinomycetospora for which the names Actinomycetospora aeridis sp. nov., Actinomycetospora flava sp. nov., and Actinomycetospora aurantiaca sp. nov., are proposed.

A clinical risk score for predicting acute kidney injury in sepsis patients receiving normal saline in Northern Thailand: a retrospective cohort study.

Normal saline is commonly used for resuscitation in sepsis patients but has a high chloride content, potentially increasing the risk of acute kidney injury (AKI). This study evaluated risk factors and developed a predictive risk score for AKI in sepsis patients treated with normal saline. This retrospective cohort study utilized the medical and electronic health records of sepsis patients who received normal saline between January 2018 and May 2020. Predictors of AKI used to construct the predictive risk score were identified through multivariate logistic regression models, with discrimination and calibration assessed using the area under the receiver operating characteristic curve (AUROC) and the expected-to-observed (E/O) ratio. Internal validation was conducted using bootstrapping techniques. AKI was reported in 211 of 735 patients (28.7%). Eight potential risk factors, including norepinephrine, the Acute Physiology and Chronic Health Evaluation II score, serum chloride, respiratory failure with invasive mechanical ventilation, nephrotoxic antimicrobial drug use, history of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers use, history of liver disease, and serum creatinine were used to create the NACl RENAL-Cr score. The model demonstrated good discrimination and calibration (AUROC, 0.79; E/O, 1). The optimal cutoff was 2.5 points, with corresponding sensitivity, specificity, positive predictive value, and negative predictive value scores of 71.6%, 72.5%, 51.2%, and 86.4%, respectively. The NACl RENAL-Cr score, consisting of eight critical variables, was used to predict AKI in sepsis patients who received normal saline. This tool can assist healthcare professionals when deciding on sepsis treatment and AKI monitoring.

Termitomyces flavus sp. nov. (Lyophyllaceae, Agaricales), a New Species from Northern Thailand

Termitomyces flavus, collected from rainforest of northern Thailand, is described and discussed as novel species using morphological characters and phylogenetic analyses (ITS, nrLSU, and mtSSU). The novel taxa is brownish orange to brownish yellow with large basidiomata, dark and papilla perforatorium, abundant yellowish grey squamulose on the stipe surface, and bulbous at the base, thick pileus context, and broadly ellipsoid to ellipsoid basidiospores 6.0–8.8 × 4.1–6.2 μm.

Defining and cultivating creative citizenship in northern Thailand: enhancing urban livability through sustainable tourism

Purpose This qualitative investigation is one of a series of sub-investigations under an umbrella project to develop Lampang Creative Livable Tourist City. The aim of this paper is to explore the integration of sustainable tourism into the development of Lampang, a city in northern Thailand. By collaborating with government and private agencies, academics, community leaders and the people of Lampang to reskill and upskill core community groups in the city, the researchers hope to enhance active citizenship, develop relevant skills and foster leadership networks that boost Lampang’s appeal as a sustainable tourism destination. Design/methodology/approach Data were gathered from brainstorming meetings, focus group discussions, observations and in-depth interviews. After identifying key characteristics required for creative citizens of Lampang city, the researchers developed and implemented pilot curricula with five target groups. Activities were developed to nurture creative leaders and promote innovative use of traditional culture and lifestyle. Findings The findings revealed that targeted local curricula can harness the cultural capital of the local community and equip locals with a modern toolkit to lay the foundations for a creative, livable tourist city. Originality/value This study’s originality lies in its grassroots approach to defining creative citizenship. It captures local community perspectives on what constitutes a creative citizen. Moreover, this research demonstrates how custom-designed educational initiatives can effectively nurture a creative and resilient urban ecosystem. This offers a blueprint for culturally informed urban regeneration, highlighting the role of sustainable tourism in enhancing the city’s attractiveness and livability for both residents and visitors.

Organophosphate insecticide exposure and respiratory symptoms among school children in Northern Thailand: Interaction by biomass burning, dampness and season

The aim was to study associations between dialkylphosphates (DAPs), organophosphate (OP) metabolites in urine, biomarkers of OP insecticide exposure, and respiratory symptoms among children in upper northern Thailand. We recruited junior high school children in randomly selected schools in four cities (N = 337), with repeated data collection in wet and dry seasons. Urine was collected and analyzed for six OP metabolites, with creatinine adjustment. Total DAP was expressed as sum of DAPs. Data on respiratory symptoms was collected by a standardized questionnaire. Associations were analyzed by multiple logistic regression. Totally 11.3 % lived in farm families. Total DAPs concentration was higher in dry season (p = 0.002) but did not differ between farm and non-farm children. Total DAPs in wet season was associated with current wheeze (p = 0.019), current asthma attacks (p = 0.012) and attacks of breathlessness in last 12 months (p = 0.021). Total DAPs in dry season was associated with current wheeze (p = 0.042), and associations between DAPs and respiratory symptoms were stronger for dimethylphosphate metabolites (DMPs) than for diethylphosphate metabolites (DEPs). DMPs are produced by certain OP pesticides. Biomass burning inside or outside the home, and dampness or mold at home, enhanced the association between total DAPs and attacks of breathlessness.In conclusion, OP pesticide exposure, measured as urinary DAPs, was higher in dry season and similar in farm and non-farm children. OPs exposure, especially to DMP related pesticides, can increase asthmatic symptoms, especially in wet season. Combined exposure to OP and smoke from biomass burning, or dampness and mold, can further increase the prevalence of attacks of breathlessness. There is a need to reduce OP insecticide and biomass smoke exposure among Thai children. Since different pesticides can be used in different seasons, studies on respiratory health effects of OPs pesticide exposure should be done in different seasons.

A new lignicolous fungus, Rhexoacrodictys chiangraiensis (Pleurotheciales, Ascomycota), from Northern Thailand

ABSTRACT In this study, we introduce a novel species, Rhexoacrodictys chiangraiensis, collected from a decaying palm sheath (Arecaceae) in Northern Thailand. Morphological examination and phylogenetic analysis were carried out to identify the species. Maximum likelihood (ML) and Bayesian inference (BI) analyses were performed using the combined dataset of the internal transcribed spacer (ITS), large subunit ribosomal RNA (LSU), small subunit ribosomal RNA (SSU) and the RNA polymerase II second largest subunit (rpb2) loci. Phylogenetic analysis supported the introduction of the isolate as a novel taxon as it formed a basal clade to the other species of Rhexoacrodictys. Rhexoacrodictys chiangraiensis exhibits distinct morphological characteristics compared to other Rhexoacrodictys species by having obovoid to pyriform conidia that have smooth surfaces with 2–4 transverse septa and fewer longitudinal incomplete septa. The novel taxon was compared with other species of Rhexoacrodictys, and a comprehensive description and illustration are provided.

Phaeocerosperpusillus var. scabrellus (Notothyladaceae, Anthocerotophyta), a new taxon from northern Thailand.

A new variety of hornwort from northern Thailand, Phaeocerosperpusillusvar.scabrellus is described based on morphological characters and molecular phylogenetic analyses. In this study, phylogenetic analyses supported that the new variety is closely related to P.perpusillusvar.perpusillus. Morphologically, it is distinguished from the autonimic variety in nearly smooth spores under light microscope. A taxonomic description, illustrations, and light and scanning electron micrographs are provided. In addition, the new variety is assessed as Endangered (EN), demonstrating its rarity by being currently known from only three subpopulations.

Immunohistochemistry-based investigation of MYC, BCL2, and Ki-67 protein expression and their clinical impact in diffuse large B-cell lymphoma in upper Northern Thailand.

Diffuse large B-cell lymphoma (DLBCL) is an aggressive type of non-Hodgkin lymphoma (NHL) that accounts for approximately 25-40% of all NHL cases. The objective of this study was to investigate the protein expression, clinical impact, and prognostic role of MYC, BCL2, and Ki-67 in Thai DLBCL patients. A retrospective analysis was conducted on 100 DLBCL patients diagnosed between January 2018 and December 2019. Immunohistochemistry was used to assess the expression of MYC, BCL2, and Ki-67. The study revealed a significant association between extranodal involvement and positive cases of MYC and BCL2. MYC expressions were associated with Ki-67 expression, while BCL2 positivity was associated with the non-germinal center B-cell (non-GCB) subtype. However, there were no significant differences in the three-year overall survival (OS) and three-year progression-free survival (PFS) rates when using cut-off points of ≥ 40% for MYC, ≥ 50% for BCL2, and ≥ 70% for Ki-67. Notably, DLBCL cases with co-expression of MYC and BCL2 exhibited significantly inferior three-year OS compared to other cases (0% vs. 53%; p = 0.020). Multivariate analysis identified age ≥ 60 years and Eastern Cooperative Oncology Group (ECOG) performance status as independent prognostic factors. In conclusion, MYC, BCL2, and Ki-67 expression can serve as prognostic biomarkers; however, their prognostic value may vary based on the specific cut-off values used. Therefore, determining the appropriate threshold for each biomarker based on individual laboratory analyses and clinical outcomes is crucial.

Fungal conservation through a private initiative: the Mushroom Research Centre (MRC) in Thailand

The conservation of fungi is an integral part of ecosystem conservation. The Mushroom Research Centre’s strategic approach to fungal conservation offers valuable insights. Located in northern Thailand, this institution has emerged as a research and training hub for mycologists across Asia, providing them with practical knowledge and skills. Its influence has not been limited to the region, making it a compelling case study for the potential impact of private conservation initiatives.

Fish diversity in the Nong Leng Sai Wetland, Phayao Province, Northern Thailand, after deep-water dredging

Abstract. Tuncharoen S, Manetam K, Pornpuang S, Chaisan W, Panprommin D, Soonthornprasit K, Pitakpol S. 2024. Fish diversity in the Nong Leng Sai Wetland, Phayao Province, Northern Thailand, after deep-water dredging. Biodiversitas 25: 2738-2746. This study aimed to explore changes in the diversity of fish species in the Nong Leng Sai Wetland, Mae Chai District, Phayao Province, Northern Thailand, after just completed deep-water dredging while shallow-water dredging is in progress. Therefore, three different gill net mesh sizes collected fish specimens from January to July 2022. The results showed that 25 species belong to 23 genera, 13 families from 7 orders, and 21 native and 4 introduced fish species. The fish comprised of the miscellaneous group was the most composed by weight and number, accounting for 45.5% and 52%, respectively, followed by the carp, 38.6% by weight and 45.6% by number. The fish diversity after dredging has decreased, including species and quantity, compared to the diversity reported before. Physical changes in the Nong Leng Sai Wetland resulted from deep water dredging, including increasing water depth, more water storage volume, increased turbidity, and lack of fish shelter and natural food, affecting the diversity of fish species. Furthermore, dredging has stimulated the recovery of aquatic ecosystems regarding water quality, habitat of aquatic animals, and appropriate natural food, which is important for increasing the diversity of fish species and quantities.

Genomic Characterization and Antimicrobial Resistance of Four Mcr-1 Escherichia coli Strains Isolated from Human and Environment Sources, Hainan Province, Tropical China

Background: The rapid spread of multidrug-resistant gram-negative bacteria, particularly the increase in carbapenem-resistant strains, has led to a critical level of resistance in clinical settings. Colistin is considered to be the last line of defense against these gram-negative bacteria. Objectives: This study aims to investigate the genetic characteristics and antimicrobial resistance (AMR) patterns of four mcr-1 (mobile colistin resistance) Escherichia coli isolates from various sources in Hainan Province, tropical China, and to determine their genetic relationships with both domestic and global strains. Methods: Samples were collected from swimming pools, marine beaches, and beach personnel in Haikou and Sanya, Hainan Province, China. E. coli isolates were obtained, multilocus sequence typing was performed, and the mcr family resistance genes were amplified by polymerase chain reaction. The mobile sequences, AMR genes, phenotypes, and virulence genotypes of the mcr-1 strains were analyzed. Phylogenetic analyses were conducted to investigate the relationships between the mcr-1E. coli strains and those in the NCBI database. Results: In the current study, the mcr-1 resistance gene was detected in 4 strains, accounting for 2.94% (4/136) of the total. The 4 strains of E. coli were isolated from a freshwater swimming pool, a pool wall, seawater, and a human body. Among the four strains, the minimum inhibitory concentration of polymyxin was 8 mg/L, except for one strain, which showed low-level resistance at 4 mg/L. All four strains showed complete resistance to ampicillin, three were resistant to compound sulfamethoxazole and chloramphenicol, and all strains were sensitive to other common antibiotics. The virulence genes cfaA, cfaB, cfaC, and cfaD/cfaE were detected in all E. coli strains. The insertable sequence IS3 was the most widely distributed type. Three isolates were identified as ST987, whereas the isolate from marine sources was identified as ST24. Comparison of the core genes of the strains indicated that the four strains were closely related to the Chrysomya sp. from Northern Thailand. Conclusions: The four mcr-1 genes can mediate low to medium levels of colistin resistance, facilitating their dissemination within the population and the environment. It is crucial to trace the source of multidrug-resistant bacteria in recreational water, which is in direct contact with humans, and to reduce the risks to human health through effective supervision.

One new species and a new record of saprobic fungi from Ananas comosus in northern Thailand

Pineapple is one of the major crops in northern Thailand. Like all the other plants, it has associated with it, a wide range of fungi, which may be saprobic, pathogenic, or endophytic. This study investigated fungi associated with pineapple in Chiang Rai Province, northern Thailand. Based on morphology and multilocus phylogeny of the ITS and LSU sequence data, Anthracocystis ananatum is described as a new species with its detailed asexual morph. Compared to other Anthracocystis species, A. ananatum has a distinctive morphotype that includes septate hyphae, conidigenous cells, and conidiophores. In addition, Spegazzinia tessarthra is reported for the first time as a new host and geographic record. The complete descriptions, photo-micrographs, and phylogenies of the new species Anthracocystis ananatum and a new host and geographic record S. tessarthra are provided and discussed.

Contamination of Streptococcus suis and S. suis Serotype 2 in Raw Pork and Edible Pig Organs: A Public Health Concern in Chiang Mai, Thailand.

Streptococcus suis is one of the most important zoonotic pathogens causing serious diseases in both pigs and humans, especially serotype 2. In northern Thailand, there is a notable prevalence of S. suis infection in humans and transmission has occurred mainly through the consumption of raw pork products. Despite the continued practice of consuming raw pork in this region, limited data exist regarding S. suis contamination in such products. Therefore, this study aimed to assess the prevalence of S. suis and S. suis serotype 2 in retail raw pork meat and edible pig organs sold in Chiang Mai city, Thailand. A total of 200 samples, comprising raw pork meat and edible pig organs, were collected from nine fresh markets in Chiang Mai city between May and July 2023. Samples were prepared and cultured in Todd-Hewitt broth. Bacterial DNA was extracted and tested for any serotypes of S. suis and serotype 2 using loop-mediated isothermal amplification (LAMP) techniques. The study revealed contaminations of S. suis and serotype 2 at rates of 84% and 34%, respectively, with a higher prevalence observed in pig organs compared to raw pork. Both S. suis and serotype 2 were detected across all nine fresh markets investigated. The prevalence of S. suis remained consistently high throughout the study period, whereas serotype 2 showed peaks in May and July. These high rates of contamination indicate that people who consume or work in close contact with raw pork or edible pig organs are at a high risk of S. suis infection. Urgent implementation and maintenance of food safety campaigns and public health interventions are crucial for disease prevention and control.

Pesticide exposure and blood cholinesterase levels among adolescents from farming families in Northern Thailand.

Adolescents living in agricultural communities may be at risk for the adverse effects of pesticide exposure because they are involved in agriculture either as a career or to support their families. The purpose of this study was to investigate the association of farm activities related to pesticide exposure on blood cholinesterase (ChE) levels among adolescents from farming families in the north of Thailand. This cross-sectional study included 336 adolescents aged 12-19 years from farming families in Chiang Dao District, Chiang Mai Province. Data on pesticide exposure was collected using a questionnaire, and blood ChE activity was assessed using a ChE reactive paper test kit via fingerstick blood sampling. Overall, 51.2% of participants had abnormal blood ChE levels. Univariable logistic regression analysis revealed that pesticide-related activities on farms associated with abnormal ChE levels were mixing/spraying (OR=10.54; 95%CI=4.63-23.99), assisting or working in areas with pesticide application (OR=5.54; 95%CI=3.45-8.89), and harvesting (OR=3.70; 95%CI=2.35-5.82). In a multivariable model (Nagelkerke R2=0.374), mixing/spraying (OR=4.90; 95%CI=2.03-11.83) and assisting or working in areas with pesticide application (OR=2.61; 95%CI=1.49-4.57) were significantly associated with abnormal ChE levels, but harvesting (OR=1.48; 95%CI=0.84-2.61) was not significant after adjusting for sex, age in years, and entering or walking through a farm. The findings indicated that Thai adolescents living in farming families are at risk of pesticide exposure, particularly those involved in agricultural activities such as pesticide applicators. An intervention and measure to raise awareness and reduce the risk of pesticide exposure in adolescents is required.

Comparison of treatment outcome between first-line combination immunotherapy (anti-PD-L1 or anti-PD1) with or without chemotherapy and chemotherapy alone in advanced non-small cell lung cancer patients in tertiary care hospital.

Despite promising outcomes of first-line immunotherapy with or without chemotherapy in advanced non-small cell lung cancer (NSCLC), limited accessibility due to reimbursement was remain the problem in low to middle income countries. This study aimed to evaluate real-world effectiveness of immunotherapy in patients with advanced NSCLC in Northern Thailand. A retrospective, single-centered cohort, was conducted. Patients with advanced NSCLC who underwent PD-L1 testing (excluding EGFR and ALK mutations) and were treated with immunotherapy or without chemotherapy or chemotherapy alone were included. The primary end point was progression-free survival (PFS). The secondary endpoints were overall survival (OS), objective response rate (ORR), and adverse events. A total of 123 patients, of which 21 patients received immunotherapy-based regimen and 102 patients received chemotherapy alone. The median PFS was 11.9 months in immunotherapy-based group compared to 5.93 months in the chemotherapy group, with a. hazard ratio (HR) of 0.4 (95% confidence interval [CI], 0.23 to 0.68; p = 0.001). Similarly, the median OS was 26.68 months in the immunotherapy-based group and 11.21 months in the chemotherapy group, with HR of 0.42 (95% CI 0.22-0.8; p = 0.009). ORRs were significantly higher in the immunotherapy-based group, with 65% of patients showing a response compared to 32% in the chemotherapy group (p = 0.006). The result of this real-world study in patients with advanced stage NSCLC indicate that first-line immunotherapy-based regimen was associated with significantly greater PFS, OS, and ORR with a safety profile consistent with pivotal studies.

Principal and Secondary Diagnoses Related to Eye Injury: Characteristics from a tertiary center in Northern Thailand

OBJECTIVE This study aimed to explore the epidemiological characteris-tics of primary and secondary diagnoses of eye injuries requiring hospitali-zation in a tertiary referral center. METHODS The medical records of 726 patients with diagnoses of eye injury who were admitted between January 2016 and December 2019 were reviewed. RESULTS Four hundred and thirty-six of the patients (60.1%) were hospitalized with a principal diagnosis related to eye injury, while 290 patients (39.9%) were admitted with secondary diagnoses. Over the four-year period of study, the proportion of admissions with a principal diagnosis stayed consistently in the range of 54.0% to 63.9%. Most of the patients in the principal diagnosis group were age between 41 and 60 years. Patients in the secondary diagnosis group, however, were mostly between the age of 21 and 40 years. The majority of patients in the principal diagnosis group (267 patients, 61.2%) had eye injuries which had occurred at work, whereas in the secondary diagnosis group most (230 patients, 79.3%) had eye injuries resulting from traffic accidents. CONCLUSIONS Work-related accidents and traffic accidents were the two main types of at-risk behaviors in both the primary and secondary diagnosis categories. Initiatives for public health education related to eye injuries should pay more special attention to these two primary causes of severe eye injuries. KEYWORDS principal diagnosis, secondary diagnosis, eye injury, hos- pitalization

Ricardo’s Law of Comparative Advantage in Bronze Age, Iron Age, and Early Historic Mainland Southeast Asian Metallurgy: Copper-base Metal Production, Exchange, and Consumption Behaviours at Khao Sai On, Nil Kham Haeng, Non Pa Wai, Phromthin Tai, Sab Champa, and Tha Kae in Central Thailand

Since its late 1970s to early 1980s discovery, the Khao Wong Prachan Valley (KWPV) of central Thailand has been assumed to have been a major supplier of copper in Bronze Age, Iron Age, and Early Historic Southeast Asia. KWPV was the first regional metal production system to be characterised by lead isotope (LI) analysis in the late 2000s, revealing a coherent signature easily distinguished from subsequent analyses of production systems at Phu Lon (northern Thailand) and the Vilabouly Complex (central Laos). Despite KWPV’s scale of production, its LI signature has scarcely been detected at Bronze Age metal consumption sites in nearby northeast Thailand and not at all in Iron Age assemblages. We study copper production and copper/bronze consumption behaviours of Iron Age and Early Historic sites in KWPV’s immediate vicinity: Khao Sai On, Phromthin Tai, Tha Kae, and Sab Champa. Khao Sai On and Phromthin Tai production signatures are highly consistent with those previously established, while the uranogenic tendency at Tha Kae explains outliers from Bronze Age Non Pa Wai and Nil Kham Haeng. Analysis of consumption assemblages reveals little to no consistency with local production signatures. This tendency was tested with LI Iron Age and Early Historic datasets for Ban Khu Muang, Ban Mai Chaimongkol, Ban Pong Manao, and Ban Pong Takhob. The pattern is clear: central Thai populations imported copper/bronze, potentially from the Vilabouly Complex or production loci with closely comparable signatures. We examine this counterintuitive behaviour inductively using Ricardo’s Law of Comparative Advantage combined with a technological appreciation of the relatively low productivity of central Thai primary copper production. This suggests central Thailand’s unattached copper producers freely exchanged copper for exotic goods (bronze, glass, semi-precious stone), with potentially poor terms of exchange, from their desire to participate in wider regional trends in conspicuous consumption.

Application of MALDI-TOF MS to Identify and Detect Antimicrobial-Resistant Streptococcus uberis Associated with Bovine Mastitis.

Streptococcus uberis is a common bovine mastitis pathogen in dairy cattle. The rapid identification and characterization of antimicrobial resistance (AMR) in S. uberis plays an important role in its diagnosis, treatment, and prevention. In this study, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to identify S. uberis and screen for potential AMR biomarkers. Streptococcus uberis strains (n = 220) associated with bovine mastitis in northern Thailand were identified using the conventional microbiological methods and compared with the results obtained from MALDI-TOF MS. Streptococcus uberis isolates were also examined for antimicrobial susceptibility using a microdilution method. Principal component analysis (PCA) and the Mann-Whitney U test were used to analyze the MALDI-TOF mass spectrum of S. uberis and determine the difference between antimicrobial-resistant and -susceptible strains. Using MALDI-TOF MS, 73.18% (161/220) of the sampled isolates were identified as S. uberis, which conformed to the identifications obtained using conventional microbiological methods and PCR. Using PCR, antimicrobial-resistant strains could not be distinguished from antimicrobial-susceptible strains for all three antimicrobial agents, i.e., tetracycline, ceftiofur, and erythromycin. The detection of spectral peaks at 7531.20 m/z and 6804.74 m/z was statistically different between tetracycline- and erythromycin-resistant and susceptible strains, respectively. This study demonstrates a proteomic approach for the diagnosis of bovine mastitis and potentially for the surveillance of AMR among bovine mastitis pathogens.