Algorithms as Folding: Reframing the Analytical Focus. 6(2): 1-12.

This article proposes an analytical approach to algorithms that stresses operations of folding. The aim of this approach is to broaden the common analytical focus on algorithms as biased and opaque black boxes, and to instead highlight the many relations that algorithms are interwoven with. Our proposed approach thus highlights how algorithms fold heterogeneous things: data, methods and objects with multiple ethical and political effects. We exemplify the utility of our approach by proposing three specific operations of folding—proximation, universalisation and normalisation. The article develops these three operations through four empirical vignettes, drawn from different settings that deal with algorithms in relation to AIDS, Zika and stock markets. In proposing this analytical approach, we wish to highlight the many different attachments and relations that algorithms enfold. The approach thus aims to produce accounts that highlight how algorithms dynamically combine and reconfigure different social and material heterogeneities as well as the ethical, normative and political consequences of these reconfigurations

Effect of early, short-term supplementation on weight and linear growth of 4-7-mo-old infants in developing countries : a four-country randomized trial

The effect of supplementation on growth was tested by means of four similar controlled randomized trials in the Congo (n = 120), Senegal (n = 110), Bolivie (n = 127), and New Caledonia (n = 90). Four month-old infants were randomly allocated to supplement or control groups. A cereal-based precooked porridge was offered twice daily for 3 mo and consumption was monitored. Both groups were free to eat local food. At 7 mo of age, all infants were still breast-fed in the Congo, Senegal, and Bolivia compared with 47% in the New Caledonia. Mean daily consumption of the supplement varied among countries (558-790 kJ/d). Mean length at 4 mo was lowest in Bolivia, higher in Senegal and the Congo, and near the National Center for Health Statistics reference in New Caledonia. The mean 4-7 mo length increment was 0,48 cm higher for supplemented than for control infants in Senegal (P < 0.05), whereas weight increments did not differ. No significant effect was found in the other countries. (Résumé d'auteur

Improving adherence to acute low back pain guideline recommendations with chiropractors and physiotherapists: the ALIGN cluster randomised controlled trial

Background Acute low back pain is a common condition, has high burden, and there are evidence-to-practice gaps in the chiropractic and physiotherapy setting for imaging and giving advice to stay active. The aim of this cluster randomised trial was to estimate the effects of a theory- and evidence-based implementation intervention to increase chiropractors’ and physiotherapists’ adherence to a guideline for acute low back pain compared with the comparator (passive dissemination of the guideline). In particular, the primary aim of the intervention was to reduce inappropriate imaging referral and improve patient low back pain outcomes, and to determine whether this intervention was cost-effective. Methods Physiotherapy and chiropractic practices in the state of Victoria, Australia, comprising at least one practising clinician who provided care to patients with acute low back pain, were invited to participate. Patients attending these practices were included if they had acute non-specific low back pain (duration less than 3 months), were 18 years of age or older, and were able to understand and read English. Practices were randomly assigned either to a tailored, multi-faceted intervention based on the guideline (interactive educational symposium plus academic detailing) or passive dissemination of the guideline (comparator). A statistician independent of the study team undertook stratified randomisation using computer-generated random numbers; four strata were defined by professional group and the rural or metropolitan location of the practice. Investigators not involved in intervention delivery were blinded to allocation. Primary outcomes were X-ray referral self-reported by clinicians using a checklist and patient low back pain-specific disability (at 3 months). Results A total of 104 practices (43 chiropractors, 85 physiotherapists; 755 patients) were assigned to the intervention and 106 practices (45 chiropractors, 97 physiotherapists; 603 patients) to the comparator; 449 patients were available for the patient-level primary outcome. There was no important difference in the odds of patients being referred for X-ray (adjusted (Adj) OR: 1.40; 95% CI 0.51, 3.87; Adj risk difference (RD): 0.01; 95% CI − 0.02, 0.04) or patient low back pain-specific disability (Adj mean difference: 0.37; 95% CI − 0.48, 1.21, scale 0–24). The intervention did lead to improvement for some key secondary outcomes, including giving advice to stay active (Adj OR: 1.96; 95% CI 1.20, 3.22; Adj RD: 0.10; 95% CI 0.01, 0.19) and intending to adhere to the guideline recommendations (e.g. intention to refer for X-ray: Adj OR: 0.27; 95% CI 0.17, 0.44; intention to give advice to stay active: Adj OR: 2.37; 95% CI 1.51, 3.74). Conclusions Intervention group clinicians were more likely to give advice to stay active and to intend to adhere to the guideline recommendations about X-ray referral. The intervention did not change the primary study outcomes, with no important differences in X-ray referral and patient disability between groups, implying that hypothesised reductions in health service utilisation and/or productivity gains are unlikely to offset the direct costs of the intervention. We report these results with the caveat that we enrolled less patients into the trial than our determined sample size. We cannot recommend this intervention as a cost-effective use of resources

Knudsen gas in a finite random tube: transport diffusion and first passage properties

We consider transport diffusion in a stochastic billiard in a random tube which is elongated in the direction of the first coordinate (the tube axis). Inside the random tube, which is stationary and ergodic, non-interacting particles move straight with constant speed. Upon hitting the tube walls, they are reflected randomly, according to the cosine law: the density of the outgoing direction is proportional to the cosine of the angle between this direction and the normal vector. Steady state transport is studied by introducing an open tube segment as follows: We cut out a large finite segment of the tube with segment boundaries perpendicular to the tube axis. Particles which leave this piece through the segment boundaries disappear from the system. Through stationary injection of particles at one boundary of the segment a steady state with non-vanishing stationary particle current is maintained. We prove (i) that in the thermodynamic limit of an infinite open piece the coarse-grained density profile inside the segment is linear, and (ii) that the transport diffusion coefficient obtained from the ratio of stationary current and effective boundary density gradient equals the diffusion coefficient of a tagged particle in an infinite tube. Thus we prove Fick's law and equality of transport diffusion and self-diffusion coefficients for quite generic rough (random) tubes. We also study some properties of the crossing time and compute the Milne extrapolation length in dependence on the shape of the random tube.Comment: 51 pages, 3 figure

Detecting Microscopic Black Holes with Neutrino Telescopes

If spacetime has more than four dimensions, ultra-high energy cosmic rays may create microscopic black holes. Black holes created by cosmic neutrinos in the Earth will evaporate, and the resulting hadronic showers, muons, and taus may be detected in neutrino telescopes below the Earth's surface. We simulate such events in detail and consider black hole cross sections with and without an exponential suppression factor. We find observable rates in both cases: for conservative cosmogenic neutrino fluxes, several black hole events per year are observable at the IceCube detector; for fluxes at the Waxman-Bahcall bound, tens of events per year are possible. We also present zenith angle and energy distributions for all three channels. The ability of neutrino telescopes to differentiate hadrons, muons, and possibly taus, and to measure these distributions provides a unique opportunity to identify black holes, to experimentally constrain the form of black hole production cross sections, and to study Hawking evaporation.Comment: 20 pages, 9 figure

The Importance of Time Congruity in the Organisation.

In 1991 Kaufman, Lane, and Lindquist proposed that time congruity in terms of an individual's time preferences and the time use methods of an organisation would lead to satisfactory performance and enhancement of quality of work and general life. The research reported here presents a study which uses commensurate person and job measures of time personality in an organisational setting to assess the effects of time congruity on one aspect of work life, job-related affective well-being. Results show that time personality and time congruity were found to have direct effects on well-being and the influence of time congruity was found to be mediated through time personality, thus contributing to the person–job (P–J) fit literature which suggests that direct effects are often more important than indirect effects. The study also provides some practical examples of ways to address some of the previously cited methodological issues in P–J fit research

Consistent Anisotropic Repulsions for Simple Molecules

We extract atom-atom potentials from the effective spherical potentials that suc cessfully model Hugoniot experiments on molecular fluids, e.g., $O_2$ and $N_2$. In the case of $O_2$ the resulting potentials compare very well with the atom-atom potentials used in studies of solid-state propertie s, while for $N_2$ they are considerably softer at short distances. Ground state (T=0K) and room temperatu re calculations performed with the new $N-N$ potential resolve the previous discrepancy between experimental and theoretical results.Comment: RevTeX, 5 figure

Reproductive ability in survivors of childhood, adolescent, and young adult Hodgkin lymphoma:a review

Background: Owing to a growing number of young and adolescent Hodgkin lymphoma (HL) survivors, awareness of (long-term) adverse effects of anticancer treatment increases. The risk of impaired reproductive ability is of great concern given its impact on quality of life. There is currently no review available on fertility after childhood HL treatment. Objective and Rationale: The aim of this narrative review was to summarize existing literature on different aspects of reproductive function in male and female childhood, adolescent, and young adult HL survivors. Search Methods: PubMed and EMBASE were searched for articles evaluating fertility in both male and female HL survivors aged &lt;25 years at diagnosis. In females, anti-Müllerian hormone (AMH), antral follicle count, premature ovarian insufficiency (POI), acute ovarian failure, menstrual cycle, FSH, and pregnancy/live births were evaluated. In males, semen-analysis, serum FSH, inhibin B, LH, testosterone, and reports on pregnancy/live births were included. There was profound heterogeneity among studies and a lack of control groups; therefore, no meta-analyses could be performed. Results were presented descriptively and the quality of studies was not assessed individually. Outcomes: After screening, 75 articles reporting on reproductive markers in childhood or adolescent HL survivors were included. Forty-one papers reported on 5057 female HL survivors. The incidence of POI was 6-34% (median 9%; seven studies). Signs of diminished ovarian reserve or impaired ovarian function were frequently seen (low AMH 55-59%; median 57%; two studies. elevated FSH 17-100%; median 53%; seven studies). Most survivors had regular menstrual cycles. Fifty-one studies assessed fertility in 1903 male HL survivors. Post-treatment azoospermia was highly prevalent (33-100%; median 75%; 29 studies). Long-term follow-up data were limited, but reports on recovery of semen up to 12 years post-treatment exist. FSH levels were often elevated with low inhibin B (elevated FSH 0-100%; median 51.5%; 26 studies. low inhibin B 19-50%; median 45%; three studies). LH and testosterone levels were less evidently affected (elevated LH 0-57%, median 17%; 21 studies and low testosterone 0-43%; median 6%; 15 studies). In both sexes, impaired reproductive ability was associated with a higher dose of cumulative chemotherapeutic agents and pelvic radiotherapy. The presence of abnormal markers before treatment indicated that the disease itself may also negatively affect reproductive function (Females: AMH&lt;p10 9%; one study and Males: azoospermia 0-50%; median 10%; six studies). Reports on chance to achieve pregnancy during survivorship are reassuring, although studies had their limitations and the results are difficult to evaluate. In the end, a diminished ovarian reserve does not exclude the chance of a live birth, and males with aberrant markers may still be able to conceive. Wider Implications: This review substantiates the negative effect of HL treatment on gonadal function and therefore young HL survivors should be counseled regarding their future reproductive life, and fertility preservation should be considered. The current level of evidence is insufficient and additional trials on the effects of HL and (current) treatment regimens on reproductive function are needed. In this review, we make a recommendation on reproductive markers that could be assessed and the timing of (repeated) measurements.</p