University of Peradeniya

Despite the economic importance of Piper nigrum (black pepper), a highly valued crop worldwide, development and utilization of genomic resources have remained limited, with diversity assessments often relying on only a few samples or DNA markers. Here we employed restriction-site associated DNA sequencing to analyze 175 P. nigrum accessions from eight main black pepper growing regions in Sri Lanka. The sequencing effort resulted in 1,976 million raw reads, averaging 11.3 million reads per accession, revealing 150,356 high-quality single nucleotide polymorphisms (SNPs) distributed across 26 chromosomes. Population structure analysis revealed two subpopulations (K = 2): a dominant group consisting of 152 accessions sourced from both home gardens and large-scale cultivations, and a smaller group comprising 23 accessions exclusively from native collections in home gardens. This clustering was further supported by principal component analysis, with the first two principal components explaining 35.2 and 12.1% of the total variation. Genetic diversity analysis indicated substantial gene flow (Nm = 342.21) and a low fixation index (FST = 0.00073) between the two subpopulations, with no clear genetic differentiation among accessions from different agro-climatic regions. These findings demonstrate that most current black pepper genotypes grown in Sri Lanka share a common genetic background, emphasizing the necessity to broaden the genetic base to enhance resilience to biotic and abiotic stresses. This study represents the first attempt at analyzing black pepper genetic diversity using high-resolution SNP markers, laying the foundation for future genome-wide association studies for SNP-based gene discovery and breeding.

Comparing two measurement methods is vital in various fields, such as medical research, epidemiology, economics, and environmental studies, to determine whether a new measurement method can be used interchangeably with an existing one. Measurement error models (MEMs) are commonly used for this purpose, where the methods have different measuring scales. However, these models often assume normality, which can be problematic when dealing with skewed and heavy-tailed data. To address this issue, we propose the replicated measurement error model (RMEM) under scale mixtures of skew-normal (SMSN) distributions with different levels of skewness and heavy tails of the true covariate and error distributions. Our primary aim is to assess the extent of similarity and agreement between two measurement methods using this model. The expectation conditional maximization (ECM) approach is applied to fit the model. A simulation study is conducted to evaluate the effectiveness and robustness of the proposed methodology and is illustrated by analyzing systolic blood pressure data. The probability of agreement is used further to assess the agreement between the two measurement methods. The findings indicate that the proposed model effectively analyses replicated method comparison data with measurement errors, even when there are outliers, skewness, and heavy-tailedness.

Poverty eradication is the first goal of the United Nations Sustainable Development Goals (SDGs) set to be achieved by 2030. As a developing country, Sri Lanka is committed to achieve these goals and to become a sustainably developed country. However, the COVID-19 pandemic and the deepening economic crisis have created a serious challenge in achieving these goals for Sri Lanka. In this context, the apparel and textile sector, one of the largest contributors to the economy, has a great role to play. The creation of direct and indirect employment and the increase in incomes and savings of households are among the significant impacts of the apparel and textile industry on the economy. However, a thorough assessment of the impact of the apparel and textile industry on poverty reduction proves challenging within the extant scholarly literature. This important gap sheds light on the aims of our study, which are to (i) investigate the impact of the apparel sector on the reduction of income poverty in Sri Lanka, (ii) explore the potential impact of the apparel and textile industry on eradicating multidimensional poverty in Sri Lanka, and (iii) examine the role of the apparel sector on fostering female empowerment in the country. This research is based on primary data, which is collected from employees in the apparel sector through a survey questionnaire. The sample size is 185 respondents who are workers in the apparel sector, covering large, medium, and small-scale apparel and textile firms island-wide. In addition, secondary data is collected from various sources. Based on the gathered data, a detailed quantitative and qualitative analysis is conducted to test the validity of the hypothesis that the apparel industry helps to reduce poverty in Sri Lanka. The findings indicate that over one-third of the sample lives below the income poverty threshold, with nearly 20% experiencing multidimensional poverty. Evidently, the apparel and textile industry significantly contributes to reducing both income and multidimensional poverty in the country.

High oncogenic risk types of human papillomaviruses are mainly transmitted via sexual contact and are the main cause of cervical cancer in females in developing countries. Molecular detection of HPV infection enables early cancer detection; however, it is not widely used in low-income countries due to resource constraints. The aim of this study was to assess economical yet sensitive HPV detection and genotyping assays for both physician and self-collected cervical samples in a resource limited diagnostic setting. A previously reported polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) based HPV detection and genotyping protocol was verified using direct DNA sequencing to accurately identify the HPV 16 and 18 genotypes in a routine-diagnostic set-up. Then the HPV prevalence in a cohort of 433 clinically normal females was performed using PCR–RFLP diagnostic tool. Finally, the performance of the PCR–RFLP HPV screening tool was further evaluated against self-collected samples. HPV 16 and 18 genotyping with the PCR–RFLP consistently agreed with the sequencing data. The HPV prevalence in the screening cohort was 5.8%. HPV 16 and 18 were the most common high-risk HPV genotypes detected in the study cohort. Self-sampling vs physician collected samples from the same subject resulted in an overall concordance of 93% for HPV detection. The PCR–RFLP protocol can be used effectively under low resource settings for HPV 16/18 diagnosis and genotyping. The self-sampling approach can be recommended to increase HPV screening among women in Sri Lanka.

In this article, a set of equations is derived to find incident and load power explicitly in terms of load and source reflection coefficients in a lossless transmission line mismatched to both source and load impedances. A transmission line can be mismatched as the frequency varies if the source and load impedances are frequency dependent. Unlike in a scenario, where the transmission line is either matched to the source or load, the incident and load power depends on the length of the transmission line when both the source and load impedances are not matched to the line. The equations derived show that the power varies with the line length with a period of half wavelength. The maximum and minimum incident and load power with the corresponding line lengths are derived. The use of the Smith chart to find these lengths and the ratio of maximum to minimum is also described. Finally, three applications of the results including an additional version of the Friis transmission equation and the bandwidth improvement of power transfer for frequency dependent source and load impedances are presented.

Sri Lanka was historically not known to be situated in a seismic hotspot. However, in 2022, the island nation experienced seven earthquakes, and in the past few months of 2023, nine seismic tremors have occurred. This marks a significant increase as typically 2–3 seismic events were reported annually. As the seismic activity in the region gains attention, it becomes imperative to understand how these seismic trends influence the stability of fragment rock slopes and nearby deposits. This paper investigates the emerging seismicity trends on the interpretation of major landslides and understanding catastrophic landslides settings in hill country. The outcomes of this study demonstrates that seismicity around Sri Lanka cannot be no longer ignored in slopes stability and should include seismic hazards assessment. Such approach will ultimately contributing to the development of effective mitigation strategies for enhancing public safety and safeguarding critical infrastructure in seismic-prone areas.

Background Systemic lupus erythematosus (SLE) is a devastating disease. Complications are related to the disease as well as treatment. Disease severity and organ involvement during the course of illness are comparatively higher in the Sri Lankan population with SLE when compared to the North Americans and Europeans. Steroids are widely used in SLE, and are a significant cause of morbidity. Objectives To assess the pattern of steroid use and defined steroid-related side effects among a national cohort of patients with systemic lupus erythematosus in Sri Lanka. Methods An island-wide, hospital-based, ongoing longitudinal follow-up study is conducted at rheumatology clinics across 14 centers in Sri Lanka. Patients who were diagnosed with SLE for at least 6 months are recruited for the study and followed up for 18 months. The data were extracted from the ongoing data base which includes 352 patients at the time of analysis. Steroid use with regard to the type and dose was analyzed. Presence of cataract, osteoporosis, avascular necrosis of the hip and diabetes mellitus after initiation of steroid therapy were considered as defined steroid related side effects (SEs). Association between current steroid usage and infection status was assessed using chi-square test at a p<0.05 significance level. Results Of the sample of 352, 96.6% (n=340) were females with a mean (SD) age of 35.7 (12.8) years. ACR/EULAR classification criteria of 2019 were fulfilled by the majority of patients (n=314, 89.2%). Nearly 60% (n=212) of patients were on steroid treatment at the time of recruitment with a median (IQR) of 7.5mg (5.0 to 15.0) daily dose of prednisolone. SEs of steroids treatment were reported as follows: avascular necrosis (n=8, 2.3%), diabetes mellitus (n=12. 3.4%), osteoporosis (n=4, 1.1%), and cataract (n=19, 5.4%). At least one SE was reported among 9.9% (n=35). Secondary analysis of data showed that only a limited number of patients had undergone screening for osteoporosis with a DXA scan due to limited resources in the country. Although 25.3% (n=89) of patients did not have a history of exposure to steroids in SLE treatment, 6 patients (6.7%) had similar complications: namely, cataract (n=5), diabetes (n=1) and avascular necrosis (n=1). Rate of infections in the current steroid users during the preceding year was 48.1% while in those who were not on steroids at enrolment, it was 45.7%. Current steroid therapy failed to show a statistically significant association with infection rate (p=0.66). Conclusion Steroid use and associated side effects remain low in the study population in comparison to internationally available data, despite more severe organ and organ system involvement reported in the same cohort in Sri Lanka. This is an impressive feat to have been achieved in a setting with constrained resources. However glucocorticoid-induced osteoporosis may be under-reported due to lack of wide access to DXA scanning. REFERENCES [1] Dandeniya C, Munidasa D, Deshapriya K, et al. AB0610 Characterization of disease severity and organ system involvement in patients with systemic lupus erythematosus in Sri Lanka- establishing a country-wide lupus cohort. Annals of the Rheumatic Diseases 2023;82:1506-1507.[2] Tse SM, Mok CC. Time trend and risk factors of avascular bone necrosis in patients with systemic lupus erythematosus. Lupus. 2017 Jun;26(7):715-722. doi: 10.1177/0961203316676384. Epub 2016 Nov 12. PMID: 27831540. [3] Shaharir SS, Hussein H, Rajalingham S, Mohamed Said MS, Abdul Gafor AH, Mohd R, Mustafar R. Damage in the Multiethnic Malaysian Systemic Lupus Erythematosus (SLE) Cohort: Comparison with Other Cohorts Worldwide. PLoS One. 2016 Nov 15;11(11):e0166270. doi: 10.1371/journal.pone.0166270. PMID: 27846298; PMCID: PMC5112785. Acknowledgements NIL Disclosure of Interests Chathurika Dandeniya: None declared, Duminda Munidasa: None declared, Kalum Deshapriya: None declared, Narani Aravinthan: None declared, Monika De Silva: None declared, Gunendrika Kasthuriratna: None declared, Uthpala Dissanayake: None declared, U.M.Asela Harsha Kumara Udagedara: None declared, Priyani Wanigasekara: None declared, Nuwan Darshana: None declared, Ben Parker: None declared, Ian N. Bruce GSK, Astra-Zeneca, Janssen, GSK, Astra-Zeneca, Aurinia, Lilly, GSK, Astra-Zeneca, Janssen, Hakmana Mudalige Anushka Ediriweera: None declared.

IRE1, BI‐1, and bZIP60 monitor compatible plant–potexvirus interactions though recognition of the viral TGB3 protein. This study was undertaken to elucidate the roles of three IRE1 isoforms, the bZIP60U and bZIP60S, and BI‐1 roles in genetic reprogramming of cells during potexvirus infection. Experiments were performed using Arabidopsis thaliana knockout lines and Plantago asiatica mosaic virus infectious clone tagged with the green fluorescent protein gene (PlAMV‐GFP). There were more PlAMV‐GFP infection foci in ire1a/b, ire1c, bzip60, and bi‐1 knockout than wild‐type (WT) plants. Cell‐to‐cell movement and systemic RNA levels were greater bzip60 and bi‐1 than in WT plants. Overall, these data indicate an increased susceptibility to virus infection. Transgenic overexpression of AtIRE1b or StbZIP60 in ire1a/b or bzip60 mutant background reduced virus infection foci, while StbZIP60 expression influences virus movement. Transgenic overexpression of StbZIP60 also confers endoplasmic reticulum (ER) stress resistance following tunicamycin treatment. We also show bZIP60U and TGB3 interact at the ER. This is the first demonstration of a potato bZIP transcription factor complementing genetic defects in Arabidopsis. Evidence indicates that the three IRE1 isoforms regulate the initial stages of virus replication and gene expression, while bZIP60 and BI‐1 contribute separately to virus cell‐to‐cell and systemic movement.

Irregular buildings are more vulnerable to seismic loading, depending on their degree of irregularity. Past studies quantify the degree of irregularity in vertically irregular buildings and study its correlation to seismic vulnerability. However, the past studies on plan irregular buildings were focused on evaluating the seismic performance only. The present study proposes a simplified method based on the degree of irregularity to identify the seismic vulnerability of plan irregular reinforced concrete (RC) buildings. Diaphragm discontinuity, re-entrant corners, non-parallel systems, and torsional irregularity are different types of plan irregularities considered in the study. For each type of plan irregularity, numerical models are developed with varying degrees of irregularity. Numerical models are subjected to incremental dynamic analysis and maximum inter-story drift was recorded to develop fragility curves. It is found that the proposed simplified method can effectively identify the seismic vulnerability of the plan irregular RC buildings based on their degree of plan irregularity. It can help to identify the most vulnerable plan irregular RC buildings at the initial stage of large-scale seismic simulation, such as Integrated Earthquake Simulations of urban areas. This method can be used as a filtering method to select the most vulnerable plan irregular RC buildings that need detailed seismic analyses.

Extensive areal distribution of expansive soil is a timely concern in engineering challenges. Geopolymers outperform conventional cement/lime treatment in expansive soil stabilization due to their superior mechanical and durability performance. However, the excessive cost and carbon footprint of commercial alkaline activators hinder geopolymer's widespread application. This study aims to derive a cost-effective, carbon-conscious mix to stabilize expansive soil using waste-based geopolymerization. Class F fly ash was activated via a novel solution of rice husk ash (RHA)-derived silicate and NaOH. Three factors (NaOH/RHA, NaOH molarity, mixing duration) were considered using the Taguchi method and utility concept for mix optimization, while further investigations were tailored to explore the effects of curing temperature (room temperature, 30 °C, and 40 °C) and the curing period (7, 14, and 28 days) on the strength development of treated soil. The results indicate that NaOH/RHA = 0.6, NaOH molarity = 3 mol/L, and a mixing duration of 40 min with curing temperatures of around 30 °C are ideal for maximizing the strength cost-effectively while significantly reducing the swell pressure (up to 28%). The shift from commercial Na 2 SiO 3 to RHA-silicate is 89% cheaper and reduces the carbon footprint by 70%. The study benefits sustainable ground stabilization and efficient waste management.

Background Outpatient care is central to both primary and tertiary levels in a health system. However, evidence is limited on outpatient differences between these levels, especially in South Asia. This study aimed to describe and compare the morbidity profile (presenting morbidities, comorbidities, multimorbidity) and pharmaceutical management (patterns, indicators) of adult outpatients between a primary and tertiary care outpatient department (OPD) in Sri Lanka. Methods A comparative study was conducted by recruiting 737 adult outpatients visiting a primary care and a tertiary care facility in the Kandy district. A self-administered questionnaire and a data sheet were used to collect outpatient and prescription data. Following standard categorisations, Chi-square tests and Mann‒Whitney U tests were employed for comparisons. Results Outpatient cohorts were predominated by females and middle-aged individuals. The median duration of presenting symptoms was higher in tertiary care OPD (10 days, interquartile range: 57) than in primary care (3 days, interquartile range: 12). The most common systemic complaint in primary care OPD was respiratory symptoms (32.4%), whereas it was dermatological symptoms (30.2%) in tertiary care. The self-reported prevalence of noncommunicable diseases (NCDs) was 37.9% (95% CI: 33.2–42.8) in tertiary care OPD and 33.2% (95% CI: 28.5–38.3) in primary care; individual disease differences were significant only for diabetes (19.7% vs. 12.8%). The multimorbidity in tertiary care OPD was 19.0% (95% CI: 15.3–23.1), while it was 15.9% (95% CI: 12.4–20.0) in primary care. Medicines per encounter at primary care OPD (3.86, 95% CI: 3.73–3.99) was higher than that at tertiary care (3.47, 95% CI: 3.31–3.63). Medicines per encounter were highest for constitutional and respiratory symptoms in both settings. Overall prescribing of corticosteroids (62.7%), vitamin supplements (45.8%), anti-allergic (55.3%) and anti-asthmatic (31.3%) drugs was higher in the primary care OPD, and the two former drugs did not match the morbidity profile. The proportion of antibiotics prescribed did not differ significantly between OPDs. Subgroup analyses of drug categories by morbidity largely followed these overall differences. Conclusions The morbidities between primary and tertiary care OPDs differed in duration and type but not in terms of multimorbidity or most comorbidities. Pharmaceutical management also varied in terms of medicines per encounter and prescribed categories. This evidence supports planning in healthcare and provides directions for future research in primary care.

The right to education is fundamental, serving as the cornerstone for personal and societal changes. In this context, educational leadership plays a primary and significant role. Higher education (HE) leadership focuses at all times and especially in crises largely on decision-making affecting the pedagogical approaches and the quality of education. The responsibility, therefore, placed on higher educational institutions even under normal circumstances is quite considerable, let alone during crises such as the COVID-19 pandemic. In the beginning, and with each intermittent resurgence, the pandemic challenged and moved the boundaries of educational leadership globally in an unprecedented way highlighting the need for Higher Educational Institutes (HEIs) to assess and reorient leadership attitudes and behaviours in the delivery of quality education. In this milieu, Sri Lanka provides a unique example of a country that has weathered a health crisis since 2020 with a ripple effect in educational, social, and economic spheres and endured a state higher education sector that was already beleaguered for decades by pedagogical, administrative, unemployment, militant faction and violence-related crises and challenges. The primary objective of the chapter is to examine the higher educational leadership of state and affiliated universities in Sri Lanka during the COVID-19 pandemic in the backdrop of the ongoing three-fold and related crises from 2020 to 2023 to highlight leadership initiatives (or lack thereof) in facing crises from HEI administrative, academic, and student (including students with disabilities) angles in the delivery of education in tandem with pre-existing ‘crises’. It includes the educational, social, and economic repercussions in its aftermath through accommodations and adaptations of university administrators, teachers, and students using primary and secondary data. Accordingly, the Chapter recommends as viable the crisis leadership framework proposed by Ralph Gigliotti in 2017 to surmount current and future crises and challenges while mitigating pre-existing ones.

Background Social media has evolved beyond its conventional purpose of communication and information sharing to become a potent tool for disseminating health and oral health awareness. This study seeks to assess the patterns and related factors of using social media platforms to access health and oral health information among Sri Lankan adults, with special emphasis to promotion of oral health awareness. Methods In March 2023, individuals aged ≥ 18 years residing in Sri Lanka, who are users of social media participated in this electronic questionnaire-based survey. Statistical analyses of the collected data were done using the SPSS version 21 software, with a p-value of < 0.05 set to determine the level of statistical significance. Results A total of 421 persons participated in this survey. Majority (68.4%) belonged to the age category of 18 to 30 years, and 55.5% were females. WhatsApp (96.8%) was the most frequently used social media platform across all age groups and both genders. Statistically significant differences were identified between genders in the usage of Telegram, Twitter, and Viber within the 18–30 years age category, with a higher percentage of males using these platforms (p ≤ 0.05). Similar significant differences were observed in the 31–40 years age group for WhatsApp and Telegram (p ≤ 0.05). Among 95.4% of online health information seekers, YouTube (74.9%) was the most popular platform. One-quarter of the respondents preferred social media platforms, and 22.3% preferred websites for obtaining oral health information. Furthermore, 74.9% had positive opinions on obtaining oral health information via social media, while only 17% reported pleasant experiences with social media platforms for oral health promotion. In assessing the reliability of oral health information on social media, 48% relied on the quality of the information. The most preferred source of oral health information was short videos from professionals (43.1%). Additionally, 69.5% reported changes in their oral health behaviours after accessing information through social media. Conclusion Social media is a viable platform for promoting public oral health awareness in Sri Lankan; hence, workable strategies need to be employed, to further ensure its effective and wider use in a culturally and socioeconomically diverse country like Sri Lanka.

Group A β haemolytic streptococcus (GAS) or Streptococcus pyogenes is a human pathogen that causes an array of infections, including pharyngitis, cellulitis, impetigo, scarlet fever, toxic shock syndrome, and necrotizing fasciitis. The present study characterizes 51 GAS isolates from invasive infections in Sri Lanka, focusing on resistance profiles, genetic determinants of resistance, and virulence markers. Isolates were tested for sensitivity to penicillin, erythromycin, clindamycin, and tetracycline. The presence of erm (A), erm (B), and mef (A) was detected in erythromycin-resistant isolates, while tet (M) was detected in the tetracycline-resistant isolates. PCR was used to identify SpeA, SpeB, SpeC, SpeF, SpeG, smez , and ssa as virulence markers. Selected GAS isolates were emm -typed using the updated CDC protocol. All 51 isolates were susceptible to penicillin. The number of isolates non-susceptible to erythromycin was 16. The commonest resistance determinant identified was erm (B) (11/16). Tetracycline non-susceptibility was found in 36 (70.6 %) isolates and 26 of them contained the tet (M) gene. Thirteen (25.5 %) isolates were resistant to both tetracycline and erythromycin, while 12 (23.5 %) isolates were sensitive to both antibiotics. The commonest virulence markers detected among the isolates were SpeB (44, 86.3 %), SpeG (36, 70.6 %), and SpeF (35, 68.6 %), while SpeJ (15, 29.4 %), SpeA (10, 19.6 %), and ssa (5,9.8 %) were less common. The emm types were diverse. In conclusion, the GAS isolates studied showed resistance to erythromycin and tetracycline, while retaining universal susceptibility to penicillin. Additionally, these isolates exhibited diverse genetic backgrounds, displaying varying patterns of virulence genes and emm types.

Argyreia is the most recently evolved genus in the Convolvulaceae, and available information suggests that most species in this family produce seeds with physical dormancy (PY). Our aim was to understand the evolution of seed dormancy in this family via an investigation of dormancy, storage behaviour, morphology and anatomy of seeds of five Argyreia species from Sri Lanka. Imbibition, germination and dye tracking of fresh intact and manually scarified seeds were studied. Scanning electron micrographs and hand sections of the hilar area and the seed coat away from the hilar area were compared. Scarified and intact seeds of A. kleiniana, A. hirsuta and A. zeylanica imbibed water and germinated to a high percentage, but only scarified seeds of A. nervosa and A. osyrensis did so. Thus, seeds of the three former species are non-dormant (ND), while those of the latter two have physical dormancy (PY); this result was confirmed by dye-tracking experiments. Since > 90 % of A. kleiniana, A. hirsuta and A. zeylanica seeds survived desiccation to 10 % moisture content (MC) and > 90 % of A. nervosa and A. osyrensis seeds with a dispersal MC of ~ 12 % were viable, seeds of the five species were desiccation-tolerant. A. nervosa and A. osyrensis have a wide geographical distribution and PY, while A. kleiniana, A. hirsuta and A. zeylanica have a restricted distribution and ND. Although seeds of A. kleiniana are ND, their seed coat anatomy is similar to that of A. osyrensis with PY. These observations suggest that the ND of A. kleiniana, A. hirsuta and A. zeylanica seeds is the result of an evolutionary reversal from PY and that ND may be an adaptation of these species to the environmental conditions of their wet aseasonal habitats.

This comprehensive review highlights the intricate interplay between maternal factors and the co-development of the microbiome and immune system in neonatal calves. Based on human and mouse studies, multiple prenatal and postnatal factors influence this process by altering the host-associated microbiomes (gut, respiratory tract, skin), microbial colonization trajectories, and priming of the immune systems (mucosal and systemic). This review emphasizes the importance of early life exposure, highlighting postnatal factors that work in synergy with maternal factors in further finetuning the co-development of the neonatal microbiome and immunity. In cattle, there is a general lack of research to identify the maternal effect on the early colonization process of neonatal calves (gut, respiratory tract) and its impact on the priming of the immune system. Past studies have primarily investigated the maternal effects on the passive transfer of immunity at birth. The co-development process of the microbiome and immune system is vital for lifelong health and production in cattle. Therefore, comprehensive research beyond the traditional focus on passive immunity is an essential step in this endeavor. Calf microbiome research reports the colonization of diverse bacterial communities in newborns, which is affected by the colostrum feeding method immediately after birth. In contrast to human studies reporting a strong link between maternal and infant bacterial communities, there is a lack of evidence to clearly define cow-to-calf transmission in cattle. Maternal exposure has been shown to promote the colonization of beneficial bacteria in neonatal calves. Nonetheless, calf microbiome research lacks links to early development of the immune system. An in-depth understanding of the impact of maternal factors on mi-crobiomes and immunity will improve the management of pregnant cows to raise immune-fit neonatal calves. It is essential to investigate the diverse effects of maternal health conditions and nutrition during pregnancy on the gut microbiome and immunity of neonatal calves through collaboration among researchers from diverse fields such as microbiology, immunology, nutrition, veterinary science , and epidemiology.

This study investigates the uncommon formation of laterite from garnet–sillimanite–gneiss (grt-sil-gn) in the Matale area, a hilly region of Sri Lanka. Geographically, laterites typically form in lowland wet zone of the country, but this research explores their genesis in a unique, less-studied hilly environment. Employing a comprehensive approach combining field observations, petrographic studies, and chemical mapping, we elucidate the contrasting mechanisms of lateritization on the dip slope and scarp slope of a cuesta landform. Our findings reveal a significant influence of weathering conditions and supergene processes on laterite formation. Dip slopes experience intense supergene activity due to deeper groundwater, promoting downward fluid flow and mineral dissolution. Conversely, scarp slopes exhibit isovolumetric leaching with reduced infiltration and enhanced fluid interaction, leading to lateritization along fractures in partially weathered grt-sil-gn. Intense supergene processes on the dip slopes involve downward fluid migration and mineral dissolution, aided by a deep groundwater table. In contrast, scarp slopes exhibit laterite formation through isovolumetric leaching in areas with reduced water infiltration and heightened fluid interaction. Evidence of lateritization includes the formation of gibbsite, hematite, or goethite, attributed to fluctuating oxic and anoxic conditions caused by fluid variations. Additionally, kaolinite patches emerged on the exterior of fully altered garnet, resulting from the weathering products and leachates of quartz, sillimanite, and feldspar. This research emphasizes the critical role of external factors, such as weathering and supergene processes, alongside parent rock composition, in influencing laterite formation. It significantly advances our understanding of lateritization in grt-sil-gn, particularly in hilly areas with lower rainfall compared to usual laterite formation zones.