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Abstract In this paper we will describe two new optimisations implemented in MadGraph5_aMC@NLO, both of which are designed to speed-up the computation of leading-order processes (for any model). First we implement a new method to evaluate the squared matrix element, dubbed helicity recycling, which results in factor of two speed-up. Second, we have modified the multi-channel handling of the phase-space integrator providing tremendous speed-up for VBF-like processes (up to thousands times faster).

Abstract Dark matter is a well-established theoretical addition to the Standard Model supported by many observations in modern astrophysics and cosmology. In this context, the existence of weakly interacting massive particles represents an appealing solution to the observed thermal relic in the Universe. Indeed, a large experimental campaign is ongoing for the detection of such particles in the sub-GeV mass range. Adopting the benchmark scenario for light dark matter particles produced in the decay of a dark photon, with α D = 0.1 and m A′ = 3m χ , we study the potential of the SHiP experiment to detect such elusive particles through its Scattering and Neutrino detector (SND). In its 5-years run, corresponding to 2 · 1020 protons on target from the CERN SPS, we find that SHiP will improve the current limits in the mass range for the dark matter from about 1 MeV to 300 MeV. In particular, we show that SHiP will probe the thermal target for Majorana candidates in most of this mass window and even reach the Pseudo-Dirac thermal relic.

Purpose: To assess the Medmont C100 test as a colour vision screening tool. Methods: One hundred and seventeen young male adults were screened with the Medmont C100, Ishihara plates, and the screening mode of the Oculus Anomaloscope tests. All subjects were tested under constant room illumination, namely that of a day light fluorescent lamp at 200 lux. Inclusion criteria were visual acuities (VA) of 20/20 or better with or without correction and absence of known ocular pathologies.Aided and unaided visual acuities were measured with the Snellen VA chart. Results: Five out of the117 subjects, were found to have red-green colour vision deficiency (CVD) with Ishihara and anomaloscope tests indicating a 4.7% CVD prevalence, while the Medmont C100 test yielded 33 cases of red-green deficiency indicating CVD prevalence of 28%. With the Ishihara test, all five subjects were identified as deutans, while the anomaloscope revealed three as deutans and two as protans, and the Medmont C100 test identified all 33 cases as protans. Conclusion: The Medmont C100 test yielded significantly higher prevalence of protan CVD compared with the Ishihara platesand Anomaloscope tests. These findings suggest that caution should be taken when using Medmont C100 test for colour vision screening as it tends togive more false positive results with bias for protans. (S Afr Optom 2011 70(1) 14-20)

Background: The Chromagen lens system comprises of tinted spectacle or contact lenses, each with a specific colour wavelength filter which controls the spectra of the light entering the eye. This study investigated whether spectacle-mounted Chromagen lenses would enhance colour perception in individuals with abnormal colour vision. Methods: The Ishihara colour test was used to test for colour vision deficiency (CVD) and also to evaluate the effect of the Chromagen spectacle lens on colour perception in 13 subjects. An Oculus Anomaloscope was used to confirm and sub-classify the types of CVD. Subjects comprised of school age children from the Riyadh area in Saudi Arabia. Results: The distribution amongst the male participants comprised two subjects with protanomaly, two with protanopia, five with deuteranomaly, and two with deuteranopia. Amongst the two female participants, one subject showed deuteranomaly, and one showed protanomaly. Different types of Chromagen spectacle lenses displayed some levels of colour vision enhancement depending on type of CVD. Conclusion: The findings support the notion that chromagen lenses could enhance colour vision perception in some cases of red-green colour vision defects. Clients with CVD should be managed on an individual case basis. (S Afr Optom 2011 70(2) 69-74)

Purpose: To investigate the relative cytotoxic effects of contact lens multipurpose solutions on cultured crystalline lenses. Methods: A comparison of the fluorescence emission levels of cultured bovine lenses as affected by three hour experimental exposure to three contact lens multipurpose solutions (COMPLETE Moisture Plus, AMO; OPTI-FREE Express, Alcon; and ReNu MultiPlus, Bausch & Lomb) was carried out. The pre- and post-exposure fluorescence levels of the lenses were obtained and values were compared to baseline and control measurements. Results: The solutions yielded varying degrees of cytotoxicity, demonstrating significant (p < 0.01) reversible reduction of cellular viability levels of the cultured crystalline lenses as revealed by the degree of fluorescence emissions in the following order (OPTI-FREE Express > ReNu MultiPlus > COMPLETE MoisturePlus multi-purpose solutions) Conclusions: The results show that OPTI-FREE Express and ReNu MultiPlus solutions exhibited more cytotoxic effect compared to COMPLETE MoisturePlus solution. The findings support reports from previous clinical and laboratory studies. These results suggest that the in vitro approach herein presented would be a valuable system for relatively inexpensive and repeatable laboratory investigations of the possible ocular surface reactions of ophthal- mic solutions, cosmetics and pharmaceuticals at pre- and during commercial phases.

Purpose: To determine the prevalence of congenital red-green colour vision defects among Saudi Arabian male and female children. Methods: The study involved 1638 elementary and high school participants (838 males, and 800 females), who were randomly selected and screened for red-green colour vision defects using the Ishihara (pseudo-isochromatic plates) test. Inclusion criteria were Snellen VA 20/20 or better and absence of known ocular pathologies.Among the females, 0.75% of the 800 participants showed CVD, with 0.25% and 0.5% demonstratingprotan and deutan defects, respectively. Conclusion: The results show that the prevalence of red-green colour deficiency among the female children from central Saudi Arabia is not significantly different from that of female populations inwestern countries. The current prevalence among the males is higher than previously reported for central Saudi Arabia, but less than for Caucasian populations.

In order to evaluate the functional aspect of myocardial neovascularization after grafting a free skeletal muscle flap onto the heart in the dog with an arterial anastomosis to the internal mammary artery (IMA), a gradual occlusion of the left anterior descending coronary (LAD) was induced. This was achieved implanting an Ameroidconstrictor on the LAD, that due to its hygroscopical material induces a gradual coronary occlusion. The occlusion of the LAD was angiographically confirmed in vivo. In one dog the selective angiographical demonstration of the IMA anastomosed to the graft was achieved. This showed retrograde filling of the LAD occluded by the Ameroidconstrictor. These findings were confirmed in all dogs by a microvascular corrosion cast preparation of the vasculature induced from the graft, that was differentiated from the coronaries by a different coloured casting material. The occluded LAD was filled in all preparations by the casting material applied into the IMA. Thus, grafting of a free skeletal muscle flap anastomosed to the IMA onto the dog's heart produces a functional myocardial neovascularization.

In plastic surgery, free skeletal muscle flaps are used for treatment of non-healing injuries like chronic osteitis or radiation ulcers. We wanted to evaluate if the neoangiogenesis induced by these flaps can also constitute a method for revascularization in ischemic heart disease. In diffuse small vessel coronary heart disease, patients are not suitable for bypass surgery because it is impossible to create a microanastomosis with the coronary artery. As an alternative, a free striated muscle flap, transplanted onto the heart, can constitute a source of neovessels. With the induction of extra-intracardial collaterals that develop within 4 weeks after transplantation of the flap, a new surgical approach may be offered to those patients. Our experimental work was performed with 20 dogs. In these, a myocardial infarction of the anterior wall was selectively produced using the Judkins-technique (Radiology 89: 815-824, 1967) for injection of Sephadex-microspheres. Four weeks later a free pectoralis muscle flap was transplanted onto the anterior wall of the heart. Arterial blood supply was achieved with an anastomosis with the internal mammary artery. The venous flow was directed into the right atrium. Four to eight weeks after surgery, the patency of the anastomosis was studied by angiography, showing patency in almost all surviving animals. Histological examination of the hearts revealed a prominent vascular network penetrating into the underlying myocardium. Corrosion cast preparations, as well as a postmortem angiography, showed even further penetration of the neovessels into the uninjured parts of the myocardium. Thus, myocardial revascularization may be achieved by transplantation of a skeletal muscle onto the heart.

A retrospective study was used to assess the diagnostic value of the metoclopramide (MCP)-stimulation test for diagnosing hormonal infertility in women. 1326 couples sought help at the hormone-counselling laboratories at the University Gynaecological Hospital in Heidelberg during a six year period and were evaluated with a standardized diagnostic program. The patients were grouped as manifestly hyperprolactinaemic, normoprolactinaemic or functionally hyperprolactinaemic, according to their basal serum prolactin (Pr)-level, and the results of the MCP-stimulation test. The number of patients in the normoprolactinaemic group varied from 894 to 1188 and functionally hyperprolactinaemic varied from 263 to 19 patients, depending on the cut-off value selected. We used cut-off values of 200, 250, 300 or 400 ng/ml in evaluating the MCP response. During a two year follow-up, 40% of the women conceived. Increasing Pr-levels, at stimulation, were associated with significantly more spontaneous pregnancies. Thus more women conceived in the functional hyperprolactinaemic group than in the normoprolactinaemic group. 281 women had used a dopamine agonist (21%). Women in the bromocriptine group (except manifestly hyperprolactinaemic patients) had significantly higher pregnancy rates than those not treated with bromocriptine. This results was particularly significant for women with normoprolactinaemic. It was caused by higher bromocriptine induced conception rate. 60% of the therapeutic pregnancies occurred in normoprolactinaemic women receiving the dopamine agonist therapy. Our results suggest that MCP-stimulation induced functional hyperprolactinaemia is not required for a successful approach. In sterility of unknown origin with normal basal Pr serum levels, a three month trial with low-dose dopamine agonist can be tried.