Benchmarking Implementations of Functional Languages with ``Pseudoknot'', a Float-Intensive Benchmark

Over 25 implementations of different functional languages are benchmarked using the same program, a floatingpoint intensive application taken from molecular biology. The principal aspects studied are compile time and execution time for the various implementations that were benchmarked. An important consideration is how the program can be modified and tuned to obtain maximal performance on each language implementation.\ud With few exceptions, the compilers take a significant amount of time to compile this program, though most compilers were faster than the then current GNU C compiler (GCC version 2.5.8). Compilers that generate C or Lisp are often slower than those that generate native code directly: the cost of compiling the intermediate form is normally a large fraction of the total compilation time.\ud There is no clear distinction between the runtime performance of eager and lazy implementations when appropriate annotations are used: lazy implementations have clearly come of age when it comes to implementing largely strict applications, such as the Pseudoknot program. The speed of C can be approached by some implemtations, but to achieve this performance, special measures such as strictness annotations are required by non-strict implementations.\ud The benchmark results have to be interpreted with care. Firstly, a benchmark based on a single program cannot cover a wide spectrum of 'typical' applications.j Secondly, the compilers vary in the kind and level of optimisations offered, so the effort required to obtain an optimal version of the program is similarly varied

Acoustic radiation- and streaming-induced microparticle velocities determined by micro-PIV in an ultrasound symmetry plane

We present micro-PIV measurements of suspended microparticles of diameters from 0.6 um to 10 um undergoing acoustophoresis in an ultrasound symmetry plane in a microchannel. The motion of the smallest particles are dominated by the Stokes drag from the induced acoustic streaming flow, while the motion of the largest particles are dominated by the acoustic radiation force. For all particle sizes we predict theoretically how much of the particle velocity is due to radiation and streaming, respectively. These predictions include corrections for particle-wall interactions and ultrasonic thermoviscous effects, and they match our measurements within the experimental uncertainty. Finally, we predict theoretically and confirm experimentally that the ratio between the acoustic radiation- and streaming-induced particle velocities is proportional to the square of the particle size, the actuation frequency and the acoustic contrast factor, while it is inversely proportional to the kinematic viscosity.Comment: 11 pages, 9 figures, RevTex 4-

Future food contaminants: An assessment of the plant uptake of Technology-critical elements versus traditional metal contaminants

Technology-critical elements (TCEs) include most rare earth elements (REEs), the platinum group elements (PGEs), and Ga, Ge, In, Nb, Ta, Te, and Tl. Despite increasing recognition of their prolific release into the environment, their soil to plant transfer remains largely unknown. This paper provides an approximation of the potential for plant uptake by calculating bioconcentration factors (BCFs), defined as the concentration in edible vegetable tissues relative to that in cultivation soil. Here data were obtained from an indoor cultivation experiment growing lettuce, chard, and carrot on 22 different European urban soils. Values of BCFs were determined from concentrations of TCEs in vegetable samples after digestion with concentrated HNO3, and from concentrations in soil determined after 1) Aqua Regia digestion and, 2) diluted (0.1 M) HNO3 leaching. For comparison, BCFs were also determined for 5 traditional metal contaminants (TMCs; As, Cd, Cu, Pb, and Zn). The main conclusions of the study were that: 1) BCF values for the REEs were consistently low in the studied vegetables; 2) the BCFs for Ga and Nb were low as well; 3) the BCFs for Tl were high relative to the other measured TCEs and the traditional metal contaminants; and 4) mean BCF values for the investigated TCEs were generally highest in chard and lowest in carrot. These findings provide initial evidence that there are likely to be real and present soil–plant transfer of TCEs, especially in the case of Tl. Improvements in analytical methods and detection limits will allow this to be further investigated in a wider variety of edible plants so that a risk profile may be developed

Termination Casts: A Flexible Approach to Termination with General Recursion

This paper proposes a type-and-effect system called Teqt, which distinguishes terminating terms and total functions from possibly diverging terms and partial functions, for a lambda calculus with general recursion and equality types. The central idea is to include a primitive type-form "Terminates t", expressing that term t is terminating; and then allow terms t to be coerced from possibly diverging to total, using a proof of Terminates t. We call such coercions termination casts, and show how to implement terminating recursion using them. For the meta-theory of the system, we describe a translation from Teqt to a logical theory of termination for general recursive, simply typed functions. Every typing judgment of Teqt is translated to a theorem expressing the appropriate termination property of the computational part of the Teqt term.Comment: In Proceedings PAR 2010, arXiv:1012.455

Is the Thoughts and Health programme feasible in the context of Swedish schools? A quasi-experimental controlled trial study protocol.

Introduction: Clinical depression is a substantial problem among adolescents, increasing significantly at about age 15 years. It causes impairment in social, academic and familial relationships, as well as ongoing cognitive and emotional difficulties for the individual. A study in Iceland demonstrated that a cognitive-behavioural, developmentally based intervention programme, 'Thoughts and Health', prevented initial episodes of depression and/or dysthymia (DYS) (major depressive disorder/DYS) in adolescents for up to 12 months following completion of the programme. We would like to test the feasibility of implementing the Icelandic method in a Swedish context and to evaluate the long-term effects of such a programme. Methods and analysis: A quasi-experimental controlled design, combined with qualitative and quantitative methods, will be used to address the research questions.In this study, 617 children aged ~14 years will be screened for depression, and those "at risk" for development of clinical depression will be offered a 12 week course, 'Thoughts and Health'. This course aims to prevent first depression in adolescents. A comparable group of children will function as controls.Depending on the type of variable, baseline comparisons between the two groups of relevant initial measures will be evaluated with t-tests or χ2 analyses. The effects of the programme on the development of clinical levels of depression will be evaluated using the follow-up data of 6, 12 and 18 months. Index parental depression at baseline will be tested as a moderator in the evaluation of the effects of the prevention programme. Ethics and dissemination: This study is approved by the Swedish Ethical Review Board (reference number 2019-03347) in Gothenburg.We plan to disseminate the knowledge gained from this study by publishing our results in peer-reviewed scientific journals and other scholarly outlets. Trial registration number: NCT04128644; Pre-results. Keywords: child & adolescent psychiatry; depression & mood disorders; public health.Peer reviewe

Is the Thoughts and Health programme feasible in the context of Swedish schools? A quasi-experimental controlled trial study protocol.

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadIntroduction: Clinical depression is a substantial problem among adolescents, increasing significantly at about age 15 years. It causes impairment in social, academic and familial relationships, as well as ongoing cognitive and emotional difficulties for the individual. A study in Iceland demonstrated that a cognitive-behavioural, developmentally based intervention programme, 'Thoughts and Health', prevented initial episodes of depression and/or dysthymia (DYS) (major depressive disorder/DYS) in adolescents for up to 12 months following completion of the programme. We would like to test the feasibility of implementing the Icelandic method in a Swedish context and to evaluate the long-term effects of such a programme. Methods and analysis: A quasi-experimental controlled design, combined with qualitative and quantitative methods, will be used to address the research questions.In this study, 617 children aged ~14 years will be screened for depression, and those "at risk" for development of clinical depression will be offered a 12 week course, 'Thoughts and Health'. This course aims to prevent first depression in adolescents. A comparable group of children will function as controls.Depending on the type of variable, baseline comparisons between the two groups of relevant initial measures will be evaluated with t-tests or χ2 analyses. The effects of the programme on the development of clinical levels of depression will be evaluated using the follow-up data of 6, 12 and 18 months. Index parental depression at baseline will be tested as a moderator in the evaluation of the effects of the prevention programme. Ethics and dissemination: This study is approved by the Swedish Ethical Review Board (reference number 2019-03347) in Gothenburg.We plan to disseminate the knowledge gained from this study by publishing our results in peer-reviewed scientific journals and other scholarly outlets. Trial registration number: NCT04128644; Pre-results. Keywords: child & adolescent psychiatry; depression & mood disorders; public health.Region Vastra Gotaland, Swede

Automatic generation of hardware/software interfaces

Enabling new applications for mobile devices often requires the use of specialized hardware to reduce power consumption. Because of time-to-market pressure, current design methodologies for embedded applications require an early partitioning of the design, allowing the hardware and software to be developed simultaneously, each adhering to a rigid interface contract. This approach is problematic for two reasons: (1) a detailed hardware-software interface is difficult to specify until one is deep into the design process, and (2) it prevents the later migration of functionality across the interface motivated by efficiency concerns or the addition of features. We address this problem using the Bluespec Codesign Language~(BCL) which permits the designer to specify the hardware-software partition in the source code, allowing the compiler to synthesize efficient software and hardware along with transactors for communication between the partitions. The movement of functionality across the hardware-software boundary is accomplished by simply specifying a new partitioning, and since the compiler automatically generates the desired interface specifications, it eliminates yet another error-prone design task. In this paper we present BCL, an extension of a commercially available hardware design language (Bluespec SystemVerilog), a new software compiling scheme, and preliminary results generated using our compiler for various hardware-software decompositions of an Ogg Vorbis audio decoder, and a ray-tracing application.National Science Foundation (U.S.) (NSF (#CCF-0541164))National Research Foundation of Korea (grant from the Korean Government (MEST) (#R33-10095)