Role Of Diversity Research Articles

The role of strigolactone structural diversity in the host specificity and control of Striga, a major constraint to sub‐Saharan agriculture

Social Impact StatementThe parasitic weed Striga affects crops such as sorghum, maize, millet, and rice in over 40 countries on the African continent and negatively impacts the livelihood of over 300 million small‐holder farmers. Striga seeds can remain dormant in the soil for many years until they are triggered to germinate by germination stimulants, called strigolactones, exuded from the roots of their host. Here, the current knowledge on the biosynthesis of the strigolactones, their structural diversity, and biological relevance are reviewed. This knowledge could improve Striga control and thus improve the livelihood of small‐holder farmers.SummaryThe parasitic plant genus Striga causes major yield losses to several crops such as sorghum, millet, and rice in arid and semi‐arid regions of the tropics. For Striga to successfully parasitize its host plant, two conditions should be fulfilled: suitable germination conditions and the presence of a host plant that exudes so‐called germination stimulants, strigolactones, that are also as a signal to attract beneficial micro‐organisms such as arbuscular mycorrhizal (AM) fungi. Different plant species exude qualitatively and quantitatively different blends of strigolactones, and this plays a key role in determining Striga host specificity. Sorghum lgs1 genotypes with a mutation in a sulfotransferase (SbSOT4A), for example, exude orobanchol and are resistant to Striga, while 5‐deoxystrigol is the major strigolactone exuded by susceptible cultivars with wild type SbSOT4A. In this review, we discuss the current knowledge on the biosynthesis of the large diversity of strigolactones, how SbSOT4A may be involved in this, and how strigolactone diversity may contribute to microbiome recruitment. Finally, we discuss how knowledge on the importance of strigolactone diversity can contribute to Striga control.

Interventions for resilient nature‐based solutions: An ecological perspective

Abstract Nature‐based solutions (NbS) have emerged at the science, policy and practitioner interface to address environmental challenges facing society. NbS involve people working with nature to protect, restore or manage ecosystems. Yet NbS vary to the extent they support biological diversity which has implications for ecological resilience. We reviewed how ecological resilience has been conceptualised in the NbS literature. The literature included reference to both resilience to specific disturbances and general resilience to future environmental change. We found reporting of resilience mechanisms was limited except for afforestation efforts where there is increasing recognition of the role of species diversity in contributing to resilience. Reporting was limited for resilience mechanisms that operate within species and populations (e.g. genetic diversity) and at the landscape scale (e.g. connectivity). Resistance was overlooked despite the prevalence of NbS intended to address climate change. From the broader ecological literature, we distilled resilience mechanisms that have been identified for native and experimental ecosystems and suggested interventions for the emergence of resilience mechanisms in NbS. Synthesis. Interventions to conserve biodiversity such as retaining and restoring ecosystems, are critical given that biodiversity, within and across scales of biological organisation, underpins several ecological resilience mechanisms in NbS.

Determinants of Food Security in Rural Households: An Analysis of Dietary Diversity, Land Ownership, and Socioeconomic Factors

Background: Food security is a critical issue in rural areas, influenced by various socioeconomic factors, dietary practices, and resource ownership. Understanding the determinants of food security can help in designing effective interventions to improve the well-being of rural households. Purpose: This study aims to identify and analyze the key determinants of food security among rural households, focusing on dietary diversity, land ownership, and other socioeconomic factors. Methods: The dataset used in this study includes variables such as gender, marital status, education, land ownership, food crop cultivation, meal frequency, age, food source, Food Security Index (FSI), and Household Dietary Diversity Score (HDDS). Multiple linear regression analysis was conducted to explore the relationships between these variables and the FSI. Additionally, a Random Forest Regressor model was employed to predict the FSI and to determine the importance of each feature. Results: The multiple linear regression analysis revealed that HDDS has a significant positive relationship with the FSI (p<0.001), indicating that higher dietary diversity is associated with higher food security levels. Other variables, such as education and food source, showed weaker correlations with food security. The Random Forest Regressor model achieved an R-squared value of 0.495, with feature importance analysis indicating that HDDS, food source, and age are the most influential factors in determining food security. The Mean Squared Error (MSE) of the model was 10.743. Conclusion: This research highlights the crucial role of dietary diversity and socioeconomic conditions in shaping food security outcomes in rural areas. The findings provide valuable insights for policymakers and stakeholders aiming to enhance food security and dietary quality in rural communities. Further studies are recommended to explore the complex interactions between these variables and to develop targeted interventions to improve food security.

Discriminations in remote work contexts: the pivotal role of diversity and equality management

PurposeWe examined the effect of management practices on overt and subtle forms of discrimination in remote working contexts. Management practices (i.e. diversity and equality management systems) may influence employees’ perception of the diversity climate and affect the occurrence of discrimination.Design/methodology/approachTo empirically investigate these associations, we administrated an online questionnaire with self-report measures via a 3-wave longitudinal research design.FindingsData analysis of our sample of N = 153 remotely working employees show that when managers invest in equality and diversity practices, employees perceive their workplace as more inclusive (i.e. diversity climate). In turn, this reduces the occurrence of subtle discriminations. Conversely, this relationship was not significant for overt forms of discrimination.Originality/valueThis result indicates that creating a diversity climate is especially important when combatting subtle forms of discrimination in remote work contexts. We discuss the theoretical and practical implications of our findings in light of managerial studies on discrimination at work and psychological literature on virtual environment and social networking.

Graph-Based Pan-Genome Reveals the Pattern of Deleterious Mutations during the Domestication of Saccharomyces cerevisiae.

The "cost of domestication" hypothesis suggests that the domestication of wild species increases the number, frequency, and/or proportion of deleterious genetic variants, potentially reducing their fitness in the wild. While extensively studied in domesticated species, this phenomenon remains understudied in fungi. Here, we used Saccharomyces cerevisiae, the world's oldest domesticated fungus, as a model to investigate the genomic characteristics of deleterious variants arising from fungal domestication. Employing a graph-based pan-genome approach, we identified 1,297,761 single nucleotide polymorphisms (SNPs), 278,147 insertion/deletion events (indels; <30 bp), and 19,967 non-redundant structural variants (SVs; ≥30 bp) across 687 S. cerevisiae isolates. Comparing these variants with synonymous SNPs (sSNPs) as neutral controls, we found that the majority of the derived nonsynonymous SNPs (nSNPs), indels, and SVs were deleterious. Heterozygosity was positively correlated with the impact of deleterious SNPs, suggesting a role of genetic diversity in mitigating their effects. The domesticated isolates exhibited a higher additive burden of deleterious SNPs (dSNPs) than the wild isolates, but a lower burden of indels and SVs. Moreover, the domesticated S. cerevisiae showed reduced rates of adaptive evolution relative to the wild S. cerevisiae. In summary, deleterious variants tend to be heterozygous, which may mitigate their harmful effects, but they also constrain breeding potential. Addressing deleterious alleles and minimizing the genetic load are crucial considerations for future S. cerevisiae breeding efforts.

The Role of Company Board Diversity in Corporate Adoption of Digital Inclusion Policies in the US

Objective The digital divide is increasingly becoming a source of social and economic inequality, as access to digital technologies remains limited for many populations. In response, digital inclusion initiatives have emerged to bridge this gap and provide more equal access to digital resources. These initiatives have gained significant traction in the corporate world, as companies recognise the importance of digital inclusion in expanding their customer base and fulfilling their corporate social responsibilities. However, there is limited research on the company-specific factors that influence the adoption of digital inclusion policies in companies. Methodology Using data from the ISS ESG dataset, we apply panel data methods to analyse more than a hundred technology and media companies between 2016 and 2021. Results Our findings reveal that minority CEOs and Presidents and higher representation of women on the board of directors are positively associated with increased adoption of digital inclusion policies. The results of our study extend previous research on digital inclusion/divide and determinants of ESG scored. We provide valuable insights on the role of board diversity in the adoption of digital inclusion policies and underscores the importance of diversity and inclusion in shaping equitable technology access. Limitations and Implications While this is the first study to address the determinants of corporate digital inclusion policies, its limitations are the use of a single dataset (ISS) measuring the ESG scores and the relatively low number of observations. Originality / Contribution This paper addresses this gap by exploring the impact of corporate board diversity (in particular, gender and racial/ethnic diversity) on the adoption of digital inclusion policies by US companies. To the best of our knowledge, we are the first to investigate this relationship.

The Effect of Board of Directors' Diversity on Financial Distress in Energy Companies in Indonesia

The purpose of this study is to determine the role of board diversity in the form of the presence of female directors, the presence of foreign directors, the age of directors and the size of the board of directors against the risk of financial distress by conducting logistic regression testing on energy sector companies in Indonesia during 2018-2022. The results showed that the presence of female directors and the size of the board of directors negatively affected the risk of financial distress. Further research can test separately the period before the pandemic and after the pandemic so that the characteristics of each can be known in more detail. In addition, it can add cognitive diversity factors such as education, expertise and tenure of directors. This research can be used as a reference to determine non-financial factors that can affect the possibility of financial distress experienced by the company.

PENGARUH KERAGAMAN PRODUK, FASILITAS DAN E-WOM TERHADAP KEPUASAN KONSUMEN PADA CAFE FORTUNA DENGAN KEPUTUSAN PEMBELIAN SEBAGAI VARIABEL INTERVENING

In the current era of Society 5.0, more and more unique culinary places have emerged as destinations to enjoy food and drinks known as cafes. The purpose of this study was to analyze the role of product diversity, facilities, and E-WOM in influencing consumer satisfaction and purchasing decisions at Cafe Fortuna. The population in this study were Cafe Fortuna consumers. The sampling technique was determined by simple random sampling. Data analysis and hypothesis testing in this study used the Structural Equation Model-Partial Last Square (PLS-SEM). The results of the direct effect hypothesis test using the Smart PLS 3.0 application, show that product diversity has a significant positive effect on purchasing decisions, facilities have a negative but insignificant effect on purchasing decisions, E-Wom has a positive but insignificant effect on purchasing decisions, product diversity has a positive but significant effect on customer satisfaction, facilities have a negative but insignificant effect on customer satisfaction, facilities have a positive effect on customer satisfaction, purchasing decisions have a significant positive effect on customer satisfaction through purchasing decisions, product diversity has a significant positive effect on customer satisfaction through purchasing decisions, facilities have a negative but insignificant effect on customer satisfaction through purchasing decisions, E-Wom has a positive but insignificant effect on customer satisfaction through purchasing decisions.

CEO hubris and corporate carbon footprint: The role of gender diversity

AbstractThis paper investigates the effect of an overconfident CEO on firm greenhouse gas emissions. Using panel data of 160,115 firm‐year observations from 41 countries for 2000–2021, we find a negative relationship between CEO overconfidence and greenhouse gas emissions. Additionally, drawing on the theories of gender socialisation and diversity, we find that great representation of females on the board further compels overconfident CEOs to reduce firm carbon emissions. Our findings are robust to varying estimation techniques and identification strategies. These findings offer important insights to green investors, corporate boards, managers and policymakers on the role of overconfident CEOs and female leadership in the carbon abatement efforts of public companies.

Examining the relationship between CEO power and modern slavery disclosures: The moderating role of board gender diversity in UK companies

AbstractDrawing on agency and gender socialisation theories, this study examines the effect of Chief Executive Officer (CEO) power on corporate modern slavery disclosures (MSD) and investigates whether board gender diversity might influence this relationship. Based on a sample comprising the Financial Times Stock Exchange (FTSE) 100 companies from 2016 to 2020, the findings indicate that, although there has been progress in corporate transparency concerning modern slavery, a significant gap persists in the reporting on the measurement and monitoring of the effectiveness of their policies. This may stem from powerful CEOs' desires to maintain a positive corporate image, leading to minimal disclosure of potentially damaging information. The fixed effects panel regression analysis reveals a negative relationship between CEO power (CEOP) and the extent of modern slavery disclosures (MSD), with a significant moderating effect observed when female board representation is substantial. This evidence suggests that female board members may challenge groupthink and introduce diverse perspectives that can alter the board's dynamics, potentially mitigating the negative impact of CEOP on issues like modern slavery disclosure by encouraging more ethical and collective decision‐making. This research underscores the need for greater transparency and accountability in addressing modern slavery and promoting more responsible business practices.

Post-fire vegetation dynamics of a temperate mixed forest: An assessment based on the variability of Landsat spectral indices

Fire plays a critical role in nutrient cycling and species diversity but also causes severe disturbances to ecosystems. Despite remote sensing has emerged as a valuable tool to study wildfires, a lack of information regarding post-fire dynamics still remains for certain regions. This study investigated the post-fire dynamics of four burned sites in the temperate forest of Chihuahua, northern Mexico from 2009 to 2017, based on the variability of spectral indices under varied topographic conditions of aspects and slopes. The Normalized Difference Vegetation index (NDVI), Soil Adjusted Vegetation Index (SAVI), Normalized Burn Ratio (NBR), and Normalized Difference Water index (NDWI) were utilized to assess vegetation recovery on the burned sites. One-way ANOVAs and Tukey´s tests were performed to evaluate separately the effects of aspect and slope on the indices’ variability (p < 0.05). In general, the NDVI measured the highest values of the burned sites along the evaluated lapse while the NDWI indicated the lowest measures. Results indicated significant effects of aspect on NDVI and SAVI (p < 0.05), while slope significantly influenced the four evaluated indices (p < 0.05).That in turn showed northern aspects and steeper slopes to have the highest post-fire vegetation recoveries. Furthermore, aspect only affected the bi-annual variability of SAVI (p < 0.05). However, the NBR and NDWI showed higher magnitudes of change among periods than the SAVI (i. e., recovery and non-recovery). Besides registering a continuous recovery of the burned sites from the wildfire events to 2015, this study revealed the NDVI and SAVI as the most useful spectral indices for assessing post-fire vegetation dynamics in the region. Besides aspect and slope, future studies could focus on the inclusion of additional indicators to more effectively assess post-fire ecosystem dynamics in northern Mexico.

Increasing biochar diversity promotes impacts of plant diversity on remediating cadmium in the soil

Abstract Biochar is a promising material for soil remediation. However, most studies testing roles of biochar in soil remediation have considered the use of single types of biochar, and the role of biochar diversity, as well as its interaction with species diversity of plant communities, has rarely been considered. We hypothesize that biochar diversity can influence impacts of plant diversity on soil remediation. We grew grassland communities consisting of three or six plant species in a Cd-contaminated soil mixed with one, two or four types of biochar, with no grassland community and no biochar addition as the controls. Without plant communities or with communities consisting of three species, total Cd was significantly lower in the soil mixed with four types of biochar than in the soil without biochar or mixed with one or two types of biochar. With communities consisting of six species, total Cd decreased with increasing number of biochar types. Without biochar addition, soil total Cd was not influenced by species richness, but with biochar addition, it was lower in the presence of communities with six species than in the absence of plant communities irrespective of how many types of biochar were added. Also, soil total Cd was lower in the presence of communities with six than with three plant species when two or four types of biochar were added. Our study indicates that increasing biochar diversity can promote the impact of plant diversity on remediating soil contaminated by heavy metals such as cadmium.

The diversity and ecological roles of insects and arachnids in arabica coffee (Coffea arabica) plantation in Palasari, Bandung Regency

Keanekaragaman komunitas artropoda dapat dijadikan sebagai bioindikator perubahan lingkungan khususnya pada sistem budi daya kopi dengan sistem pengelolaan yang beragam. Sistem pengelolaan lahan yang beragam akan menimbulkan perubahan struktur komunitas dan fungsi ekologis artropoda. Tujuan dari penelitian ini untuk menganalisis keanekaragaman dan peranan serangga dan Arachnida pada perkebunan kopi Arabika di Kabupaten Bandung. Sampel diambil dari perkebunan kopi di Desa Legok Nyenang, Kabupaten Bandung dengan menetapkan lima plot sampel berukuran 100 m2 per plot dengan jarak antar plot sejauh 50 m. Serangga dan Arachnida terestrial diambil menggunakan jaring ayun, perangkap nampan kuning, dan beating sheet. Sampel yang diperoleh diidentifikasi berdasarkan karakter morfologi hingga tingkat morfospesies. Sebanyak 269 jenis serangga (11 ordo dan 98 famili, total 669 individu) dan 23 jenis Aachnida (satu ordo dan 13 famili, total 44 individu) berhasil dikumpulkan dari perkebunan kopi Arabika Palasari. Peran ekologi yang paling beragam adalah fitofag. Spesies fitofag yang dominan adalah Nysius sp. (Hemiptera: Lygaeidae). Musuh alami yang dominan, yaitu parasitoid Megacampsomeris prismatica (Hymenoptera: Scoliidae) dan predator, Tetragnatha sp. (Araneae: Tetragnathidae), sedangkan fungsi ekologis yang jumlahnya paling rendah adalah serangga penyerbuk (Hymenoptera: Apidae). Keanekaragaman jenis serangga dan Arachnida yang ditemukan pada pertanaman kopi di Kabupaten Bandung termasuk dalam kategori tinggi (H' = 5,10), meskipun indeks kemerataan dan dominansinya tergolong rendah. Hasil penelitian ini menunjukkan bahwa pertanaman kopi merupakan ekosistem yang potensial bagi konservasi keanekaragaman hayati serangga dan Arachnida predator sehingga praktik budi daya dan pengelolaan hama harus diarahkan untuk melindungi serangga menguntungkan, seperti musuh alami dan polinator.

Exploring AI's Role in Supporting Diversity and Inclusion Initiatives in Multicultural Marketplaces

This paper explores the relationship between diversity, inclusion, and artificial intelligence (AI) in multicultural workplaces and markets. Growing recognition of the value of diversity and inclusion (D&amp;I) initiatives is changing organizational practices globally. Despite progress, challenges such as unconscious bias, resistance to change, and difficulty in measuring progress still exist.This study is based on a comprehensive literature review that adheres to academic ethical standards. These findings highlight the potential of AI to improve recruitment processes, personalize marketing strategies, and develop inclusive technologies. However, challenges such as bias in AI algorithms and limited data diversity need to be addressed.The paper emphasizes the need for ethical AI frameworks, diverse representation in AI development, and transparency in the use of AI to promote justice. AI has the potential to foster a more equitable society by encouraging diversity and inclusion. Further research is needed to explore the long-term impact of AI on diversity and inclusion and to develop ethical AI frameworks tailored to different industries and cultural contexts.The study also explores how AI can support D&amp;I initiatives by providing data-driven insights, automating processes, and offering personalized interventions to reduce bias and increase inclusivity. By reviewing recent research and case studies, this paper offers practical recommendations for leveraging AI in D&amp;I efforts, aiming to build a more inclusive and equitable workplace culture.

Identification and functional characterization of a novel cystatin in amphioxus, ancient origin of vertebrate type-2 cystatin homologues

Cystatins are well known as a vast superfamily of functional proteins participated in the reversible competitive inhibition of cysteine proteases. Currently, increasing evidences point to the extensive phylogenetic diversity and crucial immune roles of type-2 cystatins in the vertebrate species. However, no information is available regarding the homologue in cephalochordate amphioxus, the representative of most basal living chordates, whose immune regulation are still ambiguous. Here, we clearly identified the presence of type-2 cystatin gene in amphioxus Branchiostoma japonicum, termed Bjcystatin-2, which was structurally characterized by typical wedge-shaped cystatin feature. Evolutionary analyses revealed that Bjcystatin-2 is the putative ancestral type-2 cystatin for chordates, with gene diversity emerging through duplication events. The expression of Bjcystatin-2 showed tissue-specific profile and was inducible upon invasive pathogens. Significantly, the recombinant Bjcystatin-2 exhibited not merely cathepsin L inhibitory activity, but also the ability to bind with bacteria and their characteristic molecules. Furthermore, Bjcystatin-2 also showed the capacity to enhance the macrophage-driven bacterial phagocytosis and to attenuate the generation of pro-inflammatory cytokines within macrophages. In summary, these findings demonstrate that Bjcystatin-2 exhibits dual role acting as both a protease inhibitor and an immunoactive molecule, greatly enriching our understanding of immune defense mechanisms of type-2 cystatin within the amphioxus.

Genetic Variation Affects the Anti-Melanogenic Efficacy of Platycodon grandiflorus Flowers

This study investigated the utilization of by-products from Platycodon grandiflorus and the role of genetic diversity in their anti-melanogenic properties, focusing on the purple-flower (PF) and white-flower (WF) varieties. Our results show that the WF variety exhibited significantly higher anti-melanogenic activity, attributed to higher concentrations of key saponins such as platycodin D3 and platycodin D. These saponins demonstrated strong tyrosinase inhibitory effects as confirmed by molecular docking analysis. Further, the WF variety showed increased expression of genes involved in saponin biosynthesis, highlighting the role of genetic diversity in determining phytochemical composition and pharmacological efficacy. The superior anti-melanogenic activity of WF suggests its potential as a valuable ingredient in the cosmetic industry for skin-whitening products. Our findings emphasize the importance of utilizing by-products and selecting specific genotypes to enhance the quality and efficacy of plant-derived products. Future research should explore the full spectrum of bioactive compounds in P. grandiflorus, investigate sustainable extraction methods, and conduct clinical trials to validate the safety and effectiveness of these compounds in cosmetic and therapeutic applications.

When R&amp;D investment improves firm value: the role of board gender diversity

Purpose Agency theory postulates that research and development (R&amp;D) investments are subject to managerial discretion and thus may not enhance firm value as expected. The inconclusive empirical findings in the literature is a testament of that. This paper aims to investigate the interplay between board gender diversity (i.e. women on boards) and value relevance of firms’ effort to innovate as indicated by firms’ R&amp;D investments. Design/methodology/approach Through a sample of 1,626 US-listed firms from the period 2004 to 2019, the authors examine whether board gender diversity promotes or hampers value relevance of firms’ efforts to innovate. The authors use ordinary least squares as the baseline model and address potential endogeneity through instrumental variable two-stage least square, and selection bias through Heckman selection model. Finally, the authors use the financial crisis of 2008 as a natural experiment to investigate the effect of board gender diversity during the crisis period. Findings The results show that board gender diversity positively moderates the relation between R&amp;D and firm value. In times of financial crisis, R&amp;D does not destroy firm value in firms with gender diverse board. The results are robust to measurement error, endogeneity issue, particularly simultaneity and selection bias. Practical implications The findings in this study have several practical implications. Firms that invest heavily in R&amp;D should be mindful of gender diversity in their board recruitment strategies to enhance innovation outputs and firm value. Current and potential investors (i.e. shareholders) should take into consideration board gender diversity in their investment decision-making processes as the results show that gender diverse boards promote more effective governance, which, in turn, leads to better alignment of R&amp;D investments with shareholder value. Regulators aiming to improve corporate governance policies should encourage gender diversity on the boards. The results align with global initiatives such as the United Nations Sustainable Development Goals, particularly Goal 5 on gender equality. Policymakers may use the findings in this study to advocate for more gender diverse governance structures within corporations. Originality/value This study investigates the role gender diverse boards play in creating value from firms’ R&amp;D activities.

ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI MINAT BELI ULANG PADA SWALAYAN KOPERASI GUYUB RUKUN DI PANARUKAN DENGAN KEPUASAN KONSUMEN SEBAGAI VARIABEL INTERVENING

In the current era of globalization, of course, there are many developments that are very rapid and increasingly sophisticated, one of which is the development of retail business businesses. The purpose of this study is to analyze the Role of Product Diversity, Service Quality, and Facilities in influencing Consumer Satisfaction and Repurchase Interest in Guyub Rukun Cooperative Supermarket in Panarukan. This research is an explanatory research. The population in this study is the consumers of the Guyub Rukun Cooperative Supermarket in Panarukan. The sampling technique was determined by simple random sampling. Data analysis and hypothesis testing in this study used the Structural-Partial Least Square Equation Model (PLS-SEM). The results of the direct influence hypothesis test using the Smart PLS 3.0 application, showed that product diversity did not have a significant effect on consumer satisfaction, Service quality did not have a significant effect on consumer satisfaction, Facilities had a significant effect on consumer satisfaction, Product diversity had a significant effect on repurchase interest, Service quality did not have a significant effect on repurchase interest, Facilities do not have a significant effect on repurchase interest, Consumer satisfaction has a significant effect on repurchase interest. The results of the indirect influence hypothesis test showed that the variable of product diversity on repurchase interest through consumer satisfaction had a negative but insignificant effect, The quality of service for repurchase interest through consumer satisfaction has a negative but not significant effect, the facility for repurchase interest through consumer satisfaction has a positive but insignificant effect.

Abstract We045: Development of SA Node Organoids: A Multicellular Approach to Biological Pacemaking

The rising prevalence of sinoatrial (SA) node dysfunction, attributed to the aging population, is emerging as a critical health issue. The SA node, a natural organoid within the heart, comprises the pacemaker cells embedded within a connective tissue matrix, insulated electrically from the surrounding atrial muscle cells. This isolated architecture, along with a heterogeneous cellular composition, is crucial for the SA node's robust pacemaking and electrical conduction. Developing methods to reconstruct this crucial heterogeneous structure could offer a long-term solution for individuals with SA node dysfunction. However, the use of current biological pacemakers, which typically involve a single cell type, has often led to unstable heart rhythms during one-month in vivo integration, challenging their long-term clinical application as biological pacemakers. To address existing SA node model limitations, we developed a SA node organoid that reproduces the human SA node's multicellular tissue structure. Initially, we developed a protocol for generating cardiac SA node organoids by employing a lentivirus to deliver dox-inducible genes for key pacemaker transcription factors, specifically TBX-18 or Shox-2. We mixed wild-type human-induced pluripotent stem cells (hiPSCs) with those modified to express TBX-18 or Shox-2. These cell mixtures were aggregated, embedded in a diluted Matrigel, and then exposed to a cardiac differentiation protocol, activating TBX-18 or Shox-2 at specific times (D1 or D7) via Dox administration. By D9, these organoids began to exhibit contraction, which lasted beyond 60 days, with notable upregulation of two transcription factors and pacemaker-specific genes following Dox treatment. Subsequently, we integrated the SA node organoid into 2D hiPSC-derived atrial muscle tissue constructs, maintaining geometric isolation within the cardiac tissue to enhance source-sink mismatch. This isolation allowed the SA node organoid to successfully trigger activity in adjacent dormant cardiomyocytes, preserving the rhythm for over 60 days. These findings could redefine the role of tissue architecture and cell diversity in the SA node's pacemaking function, potentially leading to a high-fidelity, tissue-level biological pacemaker as a new treatment strategy for SA node dysfunctions.

A high-density linkage map reveals broad- and fine-scale sex differences in recombination in the hihi (stitchbird; Notiomystis cincta)

Recombination, the process of DNA exchange between homologous chromosomes during meiosis, plays a major role in genomic diversity and evolutionary change. Variation in recombination rate is widespread despite recombination often being essential for progression of meiosis. One such variation is heterochiasmy, where recombination rates differ between sexes. Heterochiasmy has been observed across broad taxonomic groups, yet it remains an evolutionary enigma. We used Lep-MAP3, a pedigree-based software that is efficient in handling large datasets, to generate linkage maps for the hihi or stitchbird (Notiomystis cincta), utilising information from >36 K SNPs and 36 families. We constructed 29 linkage maps, including for the previously unscaffolded Z chromosome. The hihi is an endangered passerine endemic to Aotearoa New Zealand that is sexually dimorphic and exhibits high levels of sexual conflict, including sperm competition. Patterns in recombination in the hihi are consistent with those in other birds, including higher recombination rates in micro-chromosomes. Heterochiasmy in the hihi is male-biased, in line with predictions of the Haldane-Huxley rule, with the male linkage map being 15% longer. Micro-chromosomes exhibit heterochiasmy to a greater extent, contrary to that reported in other birds. At the intra-chromosomal level, heterochiasmy is higher nearer to chromosome ends and in gene-rich regions. Regions of extreme heterochiasmy are enriched for genes implicated in cell structure. This study adds an important contribution in assessing evolutionary theories of heterochiasmy and provides a framework for future studies investigating fine-scale heterochiasmy.