Unguja Ukuu, located on the Zanzibar Archipelago, eastern Africa, was an active Indian Ocean trading settlement from the mid-first millennium until the early second millennium AD. As part of recent archaeological excavations aimed at understanding the site’s transregional trade networks, geoarchaeological analyses were undertaken to document the geomorphic context of the ancient settlement. Here, we outline the results of these field and laboratory studies to discuss patterns of anthropogenic sediment deposition. Unguja Ukuu’s deep coastal stratigraphy appears to record progradation of an inhabited back-reef shore from the mid-seventh to the nineth centuries AD, perhaps in the wake of an earlier middle to late Holocene marine transgression. Excavations on the back-beach show that deposits associated with the ancient settlement include interlayered middens, paleofloors, and backshore sands and, in later phases, a peri-urban dump with dark-earth-type anthrosols developed on these deposits. Coastal progradation appears to have been driven in part by the accumulation of anthropogenic detritus and compaction of ancient surfaces. We hypothesize how the inherited, submerged relic Late Pleistocene geomorphology of the intertidal zone and later Holocene sediment supply from the hinterland may have supported the emergence of Unguja Ukuu as a trading locale, and possibly contributed to its decline in the early second millennium AD.

Spanning c. 1050–1500 CE, a burgeoning Swahili community called Chwaka built a sequence of four mortared coral mosques in their town of wattle-and-daub houses on Pemba Island, Tanzania. The mosques’ placement, construction, and use played an active role in creating and strengthening an Islamic community and help us define changes in social practice within the town and the larger polity in which it existed. It is argued that the construction of each mosque was an act of assembling, drawing people, other-than-human things and affective social practices together in ways that help tell an urban story. This research provides insights into the residents’ socioeconomic and cultural priorities and the town’s changing relationship with villagers from the surrounding region, contributing to understandings of Swahili urbanism and urban practice.

This paper presents the most extensive archaeometallurgical study of iron-smithing debris excavated in East Africa. It presents an integrated methodology, including morphological, chemical, petrographic, and contextual analysis of iron slag excavated from secondary ironworking contexts. Iron slag from three Swahili sites was analysed—Unguja Ukuu located on the southwestern coast of Zanzibar, and Tumbe and Chwaka situated in the north-east of Pemba Island. The results suggest that Unguja Ukuu smithing is associated with oxidising hearth atmospheres and high amounts of CaO, while slag from Tumbe and Chwaka indicates reducing hearth atmospheres and high silica:alumina ratios, potentially pointing to the use of a flux. Distinct technical traditions can be seen at Unguja Ukuu when compared to Tumbe and Chwaka, suggesting a regional rather than chronological pattern. Temporal continuity is evident throughout the occupation of Unguja Ukuu and between sites of different periods in north-western Pemba. The spatial distribution of iron slag at these sites suggests that smithing was taking place across the extent of Unguja Ukuu, while slag scatters were more localised and disassociated from domestic contexts at Tumbe and Chwaka. The wealth of information on technological and organisational aspects of smithing obtained during this study indicates that an integrated methodology can yield valuable data for a variety of smithing sites, irrespective of excavation strategies.

In 1585–86, a young Thomas Harriot accompanied the Virginia expedition to the Outer Banks, to establish the first English colony in North America. In preparation, he had already mastered the local Algonquian language from two Native Americans brought back to England in 1584. He was able to use this to understand indigenous society and its culture. Current archaeological research on these same settlements in the Outer Banks is providing a detailed insight into the communities he observed and confirmation of the extreme accuracy of Harriot's observations. It allows us to claim that he may have been the world's first ethnographer.

In this article, we present the results of a recent program of high-resolution radiocarbon dating on the urban sequence at Kilwa Kisiwani in southern Tanzania, including Bayesian modeling of 21 calibrated 14C dates. These data come from the 2016 excavation of a large trench directly adjacent to trench ZLL, one of the key 1960s excavations that served to establish the original chronology of the town. The new sequence reported here anchors the phases of Kilwa’s development for the first time in absolute terms. The dates, stratigraphy, and artifact assemblage offer a number of new insights into the timing and tempo of the occupation at Kilwa, notably placing the first coral buildings and coins at the end of the tenth century. Insights also include findings related to the earliest phases of settlement and periods of possible urban decline. We argue against a trend for understanding Swahili towns according to a common coastal trajectory and suggest that it is important to consider regional diversity by recognizing the particular, episodic sequence at Kilwa.

Archaeologists have long emphasized the importance of large-scale excavations and multi-year or even decades-long projects at a single site or site complex. Here, we highlight archaeological field strategies, termed coring, profiling, and trenching (CPT), that rely on relatively small-scale excavations or the collection of new samples from intact deposits in previously excavated trenches (aka test units or pits). Examples from multiple sites in Africa, Asia, and North America demonstrate that CPT is highly effective for obtaining high-resolution archaeobiological and geoarchaeological samples (e.g., faunal and botanical remains, sediments) and artefacts from areas that have seen limited or no archaeological research, little systematic application of archaeological science methods, or research only on a relatively narrow time period or geographic scale. Designed to complement large-scale excavations at single sites, CPT is ideal for multi-scalar research that works in tandem with remote sensing techniques, providing samples for detailed laboratory analyses and offering a bridge between surface surveys and large-scale excavation. Given the threats facing archaeological sites around the world from climate change and human development, as well as financial, training and infrastructure constraints, and concerns from many Indigenous communities about large excavations, we argue that CPT is an important method for addressing 21st century human-environmental research questions.

The intertidal zone, covering the nearshore fringe of coasts and islands and extending from the high-water mark to areas that remain fully submerged, encompasses a range of habitats containing resources that are as important to modern populations as they were to humans in prehistory. Effectively bridging land and sea, intertidal environments are extremely dynamic, requiring complexity and variability in how people engaged with them in the past, much as they do in the present. Here we review and reconsider environmental, archaeological, and modern socio-ecological evidence from the Zanzibar Archipelago on eastern Africa's Swahili coast, focusing on marine molluscs to gain insight into the trajectories of human engagement with nearshore habitats and resources. We highlight the potential drivers of change and/or stability in human-intertidal interactions through time and space, set against a backdrop of the significant socio-economic and socio-ecological changes apparent in the archipelago, and along the Swahili coast, during the late Holocene.

The human colonization of eastern Africa's near- and offshore islands was accompanied by the translocation of several domestic, wild and commensal fauna, many of which had long-term impacts on local environments. To better understand the timing and nature of the introduction of domesticated caprines (sheep and goat) to these islands, this study applied collagen peptide fingerprinting (Zooarchaeology by Mass Spectrometry or ZooMS) to archaeological remains from eight Iron Age sites, dating between ca 300 and 1000 CE, in the Zanzibar, Mafia and Comoros archipelagos. Where previous zooarchaeological analyses had identified caprine remains at four of these sites, this study identified goat at seven sites and sheep at three, demonstrating that caprines were more widespread than previously known. The ZooMS results support an introduction of goats to island eastern Africa from at least the seventh century CE, while sheep in our sample arrived one–two centuries later. Goats may have been preferred because, as browsers, they were better adapted to the islands' environments. The results allow for a more accurate understanding of early caprine husbandry in the study region and provide a critical archaeological baseline for examining the potential long-term impacts of translocated fauna on island ecologies.

This paper situates Eastern Africa in the early maritime trade of the Indian Ocean, reviewing evidence for connections from Egypt and Red Sea, the Gulf, and Southeast Asia from prehistory to the Islamic Period. The region played a pivotal role in developing global networks, but we argue that it has become the “forgotten south” in an era of emerging empires. One reason for this is a lack of understanding of maritime mobility around the rim of the Indian Ocean, often undertaken by small scale or specialist groups, including sea nomads. These groups are characterised as marginalised and victimised during globalisation, yet dualising into categories—such as “exploiter” and “exploiting”—oversimplifies what was almost certainly in reality a complex array of roles and activities, both in the context of East Africa and elsewhere around the Indian Ocean. Through modern scientific-based excavation and analysis, we can now begin to more fully understand these interactions.

Sample information and peptide markers

This article presents the first archaeological survey of the ornate Kidichi baths on Zanzibar. The baths were built either for or by Shihrazad, a wife of Zanzibar’s nineteenth-century ruler Said bin Sultan (1806–56). Laser scanning the ornate plaster stucco clarified two inscriptions, the precise meaning of which had been lost. By combining archaeological survey results with historical research and a translation of the inscriptions, a new narrative is presented in which the main protagonist is, unusually, female. Her story raises a host of questions relating to heritage, gender, religion and politics in modern-day Africa and beyond.

Background:The introduction of artificial intelligence (AI) in medicine has raised significant ethical, economic, and scientific controversies.Introduction:Because an explicit goal of AI is to perform processes previously reserved for human clinicians and other health care personnel, there is justified concern about the impact on patient safety, efficacy, equity, and liability.Discussion:Systems for computer-assisted and fully automated detection, triage, and diagnosis of diabetic retinopathy (DR) from retinal images show great variation in design, level of autonomy, and intended use. Moreover, the degree to which these systems have been evaluated and validated is heterogeneous. We use the term DR AI system as a general term for any system that interprets retinal images with at least some degree of autonomy from a human grader. We put forth these standardized descriptors to form a means to categorize systems for computer-assisted and fully automated detection, triage, and diagnosis of DR. The components of the categorization system include level of device autonomy, intended use, level of evidence for diagnostic accuracy, and system design.Conclusion:There is currently minimal empirical basis to assert that certain combinations of autonomy, accuracy, or intended use are better or more appropriate than any other. Therefore, at the current stage of development of this document, we have been descriptive rather than prescriptive, and we treat the different categorizations as independent and organized along multiple axes.

Background: Historically, fewer than half of American Indians and Alaska Natives (AI/AN) with diabetes received the annual diabetic retinopathy (DR) examination that is considered the minimum standard of care; this rate is similar to that of the general United States (U.S.) population with diabetes. Solution: The Indian Health Service-Joslin Vision Network (IHS-JVN) Teleophthalmology Program in 2000 to increase compliance with DR standards of care among AI/AN through validated, primary care-based telemedicine. The IHS-JVN provides remote diagnosis of DR severity, with a report including management recommendations that is returned to the patient's primary care provider. The program conforms with the American Telemedicine Association (ATA) Practice Guidelines for Ocular Telehealth-Diabetic Retinopathy. Outcomes: The IHS-JVN has been expanding incrementally since the first patients were recruited in 2000; this expansion coincides with large improvements in the annual DR examination rates reported as part of local, regional, and national regulatory compliance under the Government Performance and Results Act (GPRA). Currently, with 99 clinical implementations in 23 states, IHS-JVN is the largest primary care-based ATA validation category three telemedicine program in the U.S. Summary: This article describes the program's workflow, imaging and reading technologies, diagnostic protocols, reports to providers, training, quality assurance processes, and geographical distribution. In addition to its clinical use, the program has been utilized in research on utilization of diabetic eye care, cost-effectiveness, technology development, and DR epidemiology of the AI/AN population. Potential next steps for this program are discussed.

Contributors The following document and appendices represent the third edition of the Practice Guidelines for Ocular Telehealth-Diabetic Retinopathy. These guidelines were developed by the Diabetic Retinopathy Telehealth Practice Guidelines Working Group. This working group consisted of a large number of subject matter experts in clinical applications for telehealth in ophthalmology. The editorial committee consisted of Mark B. Horton, OD, MD, who served as working group chair and Christopher J. Brady, MD, MHS, and Jerry Cavallerano, OD, PhD, who served as cochairs. The writing committees were separated into seven different categories. They are as follows: 1. Clinical/operational: Jerry Cavallerano, OD, PhD (Chair), Gail Barker, PhD, MBA, Christopher J. Brady, MD, MHS, Yao Liu, MD, MS, Siddarth Rathi, MD, MBA, Veeral Sheth, MD, MBA, Paolo Silva, MD, and Ingrid Zimmer-Galler, MD.2. Equipment: Veeral Sheth, MD (Chair), Mark B. Horton, OD, MD, Siddarth Rathi, MD, MBA, Paolo Silva, MD, and Kristen Stebbins, MSPH.3. Quality assurance: Mark B. Horton, OD, MD (Chair), Seema Garg, MD, PhD, Yao Liu, MD, MS, and Ingrid Zimmer-Galler, MD.4. Glaucoma: Yao Liu, MD, MS (Chair) and Siddarth Rathi, MD, MBA.5. Retinopathy of prematurity: Christopher J. Brady, MD, MHS (Chair) and Ingrid Zimmer-Galler, MD.6. Age-related macular degeneration: Christopher J. Brady, MD, MHS (Chair) and Ingrid Zimmer-Galler, MD.7. Autonomous and computer assisted detection, classification and diagnosis of diabetic retinopathy: Michael Abramoff, MD, PhD (Chair), Michael F. Chiang, MD, and Paolo Silva, MD.