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This paper discusses the succession ceremony organized by Aḥmad ibn Ṭūlūn in 270/884 for his son and heir, Khumārawayh, as described by Egyptian Arabic sources, notably Sīrat Aḥmad ibn Ṭūlūn of al-Balawī, an underutilized text for Abbasid history. The paper considers three overlapping questions. First, how should the accounts be read, as “representational” or, alternatively, as prescriptive, thus of a piece with elements of the Mirror for Princes literature? Second, were Ṭūlūnid networks of loyalty and dependence solely reliant on material inducements or did individuals invest themselves in the Egyptian regime beyond the point of self-interest? The question goes to the problem of material vs. emotional ties of dependency. And, third, was Ibn Ṭūlūn successful in creating a lasting power base? The question goes to the extent to which his contemporaries signed on to his “project” of redefining relations with the Abbasid center.
Maintaining attention underlies many aspects of cognition and becomes compromised early in neurodegenerative diseases like Alzheimer’s disease (AD). The consistency of maintaining attention can be measured with reaction time (RT) variability. Previous work has focused on measuring such fluctuations during in-clinic testing, but recent developments in remote, smartphone-based cognitive assessments can allow one to test if these fluctuations in attention are evident in naturalistic settings and if they are sensitive to traditional clinical and cognitive markers of AD.
Method:
Three hundred and seventy older adults (aged 75.8 +/− 5.8 years) completed a week of remote daily testing on the Ambulatory Research in Cognition (ARC) smartphone platform and also completed clinical, genetic, and conventional in-clinic cognitive assessments. RT variability was assessed in a brief (20-40 seconds) processing speed task using two different measures of variability, the Coefficient of Variation (CoV) and the Root Mean Squared Successive Difference (RMSSD) of RTs on correct trials.
Results:
Symptomatic participants showed greater variability compared to cognitively normal participants. When restricted to cognitively normal participants, APOE ε4 carriers exhibited greater variability than noncarriers. Both CoV and RMSSD showed significant, and similar, correlations with several in-clinic cognitive composites. Finally, both RT variability measures significantly mediated the relationship between APOE ε4 status and several in-clinic cognition composites.
Conclusions:
Attentional fluctuations over 20–40 seconds assessed in daily life, are sensitive to clinical status and genetic risk for AD. RT variability appears to be an important predictor of cognitive deficits during the preclinical disease stage.
Developments in third/ninth-century Egypt relate to the wider history of the Abbasid imperial realm in a number of ways. These had to do, in one sense or another, with the fraying of the Arab Islamic empire, governed, at this point, by the Abbasid house.1 This chapter considers one such development: the turn to control over Egypt by the Turkic–Central Asian military command in Samarra. My argument is that, at a moment in which the Abbasid state was struggling to sustain its hold over a once far-flung but now shrinking domain, it ceded authority over Egypt to those same military/political circles. Egypt, in this scenario, was a key interest of the Samarran commanders and in defense of which they devoted considerable energy and resources. It was a matter of consolidating authority over the province’s considerable public wealth, to be sure, but the sources point to apparent private interests – specifically, landholdings – on the part of the commanders as well.
As clinical trials were rapidly initiated in response to the COVID-19 pandemic, Data and Safety Monitoring Boards (DSMBs) faced unique challenges overseeing trials of therapies never tested in a disease not yet characterized. Traditionally, individual DSMBs do not interact or have the benefit of seeing data from other accruing trials for an aggregated analysis to meaningfully interpret safety signals of similar therapeutics. In response, we developed a compliant DSMB Coordination (DSMBc) framework to allow the DSMB from one study investigating the use of SARS-CoV-2 convalescent plasma to treat COVID-19 to review data from similar ongoing studies for the purpose of safety monitoring.
Methods:
The DSMBc process included engagement of DSMB chairs and board members, execution of contractual agreements, secure data acquisition, generation of harmonized reports utilizing statistical graphics, and secure report sharing with DSMB members. Detailed process maps, a secure portal for managing DSMB reports, and templates for data sharing and confidentiality agreements were developed.
Results:
Four trials participated. Data from one trial were successfully harmonized with that of an ongoing trial. Harmonized reports allowing for visualization and drill down into the data were presented to the ongoing trial’s DSMB. While DSMB deliberations are confidential, the Chair confirmed successful review of the harmonized report.
Conclusion:
It is feasible to coordinate DSMB reviews of multiple independent studies of a similar therapeutic in similar patient cohorts. The materials presented mitigate challenges to DSMBc and will help expand these initiatives so DSMBs may make more informed decisions with all available information.
We present the data and initial results from the first pilot survey of the Evolutionary Map of the Universe (EMU), observed at 944 MHz with the Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The survey covers
$270 \,\mathrm{deg}^2$
of an area covered by the Dark Energy Survey, reaching a depth of 25–30
$\mu\mathrm{Jy\ beam}^{-1}$
rms at a spatial resolution of
$\sim$
11–18 arcsec, resulting in a catalogue of
$\sim$
220 000 sources, of which
$\sim$
180 000 are single-component sources. Here we present the catalogue of single-component sources, together with (where available) optical and infrared cross-identifications, classifications, and redshifts. This survey explores a new region of parameter space compared to previous surveys. Specifically, the EMU Pilot Survey has a high density of sources, and also a high sensitivity to low surface brightness emission. These properties result in the detection of types of sources that were rarely seen in or absent from previous surveys. We present some of these new results here.
Much evidence – textual, material and documentary – points to slavery in the early and medieval Islamic Middle East (c. 600-1000 CE) as a social fact, persistent and multivalent. This is especially true for the urban landscape: the presence of enslaved and freed persons would have been impossible to miss. More difficult is the reconstruction of Middle Eastern agrarian slavery. This is a survey essay with particular reference to the early Abbasid Caliphate (c. 750-950) and select questions around which debate in modern scholarship has grown. One must comb medieval Arabic texts (literary and documentary) to reconstruct patterns of early Islamic-era enslavement; the organization and dynamics of slave commerce; the demands on slave and freed labor; and the (relative) social integration of the enslaved. The Arabic/Islamic library illuminates all manner of topics, religious and secular alike. Literary references to slavery and/or enslaved persons therein are plentiful and of a great variety. One has references in works of poetry and adab, an elastic term used for a variety of Arabic prose writings. Equally numerous are references in chronicles, biographical dictionaries, and works of geography and political thought. Medieval Arabic legal and religious writings provide a considerable number of references as well.
The inhabitants of seventh-century Arabia mobilized for warfare in a manner new to that region of the Near East: the effort fell, albeit gradually, under central authority.1 Arabia had long been a highly variegated cultural zone, encompassing the Syrian Desert, southern Mesopotamia, and the Arabian Peninsula. Acting in tandem, largely nomadic tribal forces accepted the leadership of sedentary townsmen, the great number of whom belonged to the Quraysh, an influential tribe of two towns of the Hejaz region, Mecca and Medina. If Yemen and south Arabia had long known the rule of kings, and, hence, more formal military organization, only now did the central and northern stretches of the Peninsula and southern Syria experience what can thereby be considered as early state formation. The effort was driven by an equally untested set of ethical and spiritual teachings. A charismatic figure, Muḥammad ibn ʿAbdallāh (570–632), preached a strict monotheism; these teachings served as the seedbed of what would soon be known as Islam.
This introductory chapter of volume II of the Cambridge World History of Violence, which focuses on the thousand years between 500 and 1500, or what is also known as the Middle Millennium, examines .institutions and forms of violence in the geographical area including Japan and China, Central Asia, North Africa, and Europe, with two additional chapters extending coverage into Aztec and Mayan culture.The topics of this introduction are set in four contexts in which violence occurred across this broad chronology and vast territory.They are: the formation of centralized polities through war and conquest; institution building and ideological expression by these same polities; control of extensive trade networks; and the emergence and dominance of religious ecumenes.Attention is also given to the idea of how theories of violence are relevant to the specific historical circumstances discussed in the volume’s chapters. A final section on the depiction of violence, both visual and literary, demonstrates the ubiquity of societal efforts to confront meanings of violence during this longue durée.