Greek-Arabic-Latin: The transmission of mathematical texts in the Middle Ages

During the Middle Ages many Greek mathematical and astronomical texts were translated from Greek into Arabic (ca. ninth century) and from Arabic into Latin (ca. twelfth century). There were many factors complicating the study of them, such as translation from or into other languages, redactions, multiple translations, and independently transmitted scholia. A literal translation risks less in loss of meaning, but can be clumsy. This article includes lists of translations and a large bibliography, divided into sections

On the Use of the “Southern Horizons Plate” (al-ṣafīḥa al-āfāqīya dhāt al-janūb)

In the following is edited an anonymous text, in twenty-one unnumbered chapters, on the use of the southern horizons plate, from a manuscript in Istanbul dated in Jumādā II 676/November 1277. The horizons plate is a drawing of the horizons engraved on one side of one of the plates of certain astrolabes. There existed —since the tenth century AD as it seems— some literature on the construction of such plates and on their use, but it has not been studied so far. The twenty-one chapters found in the Istanbul manuscript and edited here look rather like a fragment from a longer work. Most of the chapters describe astronomical applications of these plates, but some also their use for astrological purposes

Theodosius, De diebus et noctibus

Theodosius' De diebus et noctibus was one of several texts of pre-Ptolemaic spherical astronomy. Like many other scientific texts it was translated from Greek into Arabic in the ninth century. Qusta b. Luqa was possibly the translator. In two \books" comprising altogether 33 propositions, it describes the lengths of days and nights according to the various positions of the Sun on the ecliptic with respect to the tropics. In this paper the full text of three propositions (I 1, II 20 and 21) alone is given; of the other propositions only the \enunciations" are here edited. The Arabic text is followed by an English translation with comments

Inhibitory deficits in children with attention-deficit/hyperactivity disorder: Intentional versus automatic mechanisms of attention

Application of theoretically based tasks to the study of the development of selective attention has led to intriguing new findings concerning the role of inhibitory mechanisms. This study examined inhibitory mechanisms using a countermanding task and an inhibition of return task to compare deficits in intentionally, versus reflexively, controlled inhibition of attention in children with attention deficit hyperactivity disorder. Fifty children with attention-deficit/hyperactivity disorder (ADHD) were classified into one of three subtypes: predominantly inattentive (ADHD/PI), combined (ADHD/C), and those children with ADHD/C who also met criteria for comorbid oppositional defiant disorder (ADHD/C + ODD). The groups were compared to a comparison group of children (n = 21). The countermanding task showed that the ADHD groups required more time to inhibit responses and this impairment did not differ among subtypes. With respect to reflexively controlled inhibition, compared with controls ADHD/C and ADHD/C + ODD groups showed impaired reflexive inhibition, whereas the ADHD/PI group was considerably less impaired. The findings highlight a dissociation between the two forms of inhibitory deficits among children with the inattentive subtype, and raise the possibility that the efficient operation of reflexive inhibitory mechanisms might be necessary for the development of effective intentional control of inhibition

Online Story Comprehension among Children with ADHD: Which Core Deficits are Involved?

Children with ADHD have difficulty understanding causal connections and goal plans within stories. This study examined mediators of group differences in story narrations between children ages 7-9 with and without ADHD, including as potential mediators both the core deficits of ADHD (i.e., inattention, disinhibition, planning/working memory) as well measures of phonological processing and verbal skills. Forty-nine children with ADHD and 67 non-referred children narrated a wordless book and completed tasks assessing the core deficits of ADHD, phonological processing, and verbal skills. Results revealed that, although no shorter than those of non-referred children, the narratives of children with ADHD contained fewer elements relating to the story’s causal structure and goal plan. Deficits in sustained attention accounted for the most variance in these differences. Results have implications for understanding and ameliorating the academic problems experienced by children with ADHD

The Effects of Stimulant Medication on the Online Story Narrations of Children with ADHD

The current study investigated the inclusion of goal-based story events in the online story narrations of children with ADHD, as compared with their peers, and explored the effect of stimulant medication on the narrations in children with ADHD. Children completed a narration task on two separate occasions. Children with ADHD (n = 17) completed one narration on medication and the other one on placebo. Results indicated that narrations of comparison children (n= 25) were significantly more likely than narrations of children with ADHD to include the story’s positive outcome, completion of the story’s overall goal, and specific attempts linked to the goal. Children with ADHD included a larger total number of clauses in their narrations when on stimulant medication than when on placebo, but medication showed no significant effects for any other variables. Results indicate that stimulant medication may not be effective at reducing goal-based story comprehension deficits in children with ADHD

The Effects of Stimulant Medication on Free Recall of Story Events among Children with ADHD

This study investigated group differences in the recalls of stories by children with attention-deficit/hyperactivity disorder (ADHD) and comparison peers. Further, the study examined whether stimulant medication improved the story recall of children with ADHD relative to a placebo condition. Children were asked to recall both televised and audio taped stories. Free recall protocols were assessed for what information was recalled as a function of story structure features (i.e. status on or off the causal chain and event importance) and were rated for overall coherence. Relative to comparison peers, children with ADHD showed less influence of story structure features on recall, and produced less coherent recall of the audio taped stories. Medication had only limited effects on the story recall of children with ADHD. Specifically, medication did not increase these children’s sensitivity to events central to the stories and had no effect on the coherence of children’s recalls. The implications of the results for guiding future academic interventions are discussed