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A method for identifying stopped pions in a high-resolution scintillator bar detector is presented. I apply my technique to measure the axial mass MAΔ for production of the Δ(1232) resonance by neutrino, with the result MAΔ = 1.16 ± 0.20 GeV (68% CL) (limited by statistics). The result is produced from the measured spectrum of reconstructed momentum-transfer Q2. I proceed by varying the value of MAΔ in a Rein-Sehgal-based Monte Carlo to produce the best agreement, using shape only (not normalization). The consistency of this result with recent reanalyses of previous bubble-chamber experiments is discussed.

Introduction There has been a recent explosion of research into the field of artificial intelligence as applied to clinical radiology with the advent of highly accurate computer vision technology. These studies, however, vary significantly in design and quality. While recent guidelines have been established to advise on ethics, data management and the potential directions of future research, systematic reviews of the entire field are lacking. We aim to investigate the use of artificial intelligence as applied to radiology, to identify the clinical questions being asked, which methodological approaches are applied to these questions and trends in use over time. Methods and analysis We will follow the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines and by the Cochrane Collaboration Handbook. We will perform a literature search through MEDLINE (Pubmed), and EMBASE, a detailed data extraction of trial characteristics and a narrative synthesis of the data. There will be no language restrictions. We will take a task-centred approach rather than focusing on modality or clinical subspecialty. Sub-group analysis will be performed by segmentation tasks, identification tasks, classification tasks, pegression/prediction tasks as well as a sub-analysis for paediatric patients. Ethics and dissemination Ethical approval will not be required for this study, as data will be obtained from publicly available clinical trials. We will disseminate our results in a peer-reviewed publication. Registration number PROSPERO: CRD42020154790

Background Differentiating combined pulmonary fibrosis with emphysema (CPFE) from pure emphysema can be challenging on high-resolution computed tomography (HRCT). This has antifibrotic therapy implications. Methods Twenty patients with suspected CPFE underwent late gadolinium-enhanced (LGE) thoracic magnetic resonance imaging (LGE-MRI) and HRCT. Data from twelve healthy control subjects from a previous study who underwent thoracic LGE-MRI were included for comparison. Quantitative LGE signal intensity (SI) was retrospectively compared in regions of fibrosis and emphysema in CPFE patients to similar lung regions in controls. Qualitative comparisons for the presence/extent of reticulation, honeycombing, and traction bronchiectasis between LGE-MRI and HRCT were assessed by two readers in consensus. Results There were significant quantitative differences in fibrosis SI compared to emphysema SI in CPFE patients (25.8, IQR 18.4–31.0 versus 5.3, IQR 5.0–8.1, p < 0.001). Significant differences were found between LGE-MRI and HRCT in the extent of reticulation (12.5, IQR 5.0–20.0 versus 25.0, IQR 15.0–26.3, p = 0.038) and honeycombing (5.0, IQR 0.0–10.0 versus 20.0, IQR 10.6–20.0, p = 0.001) but not traction bronchiectasis (10.0, IQR 5–15 versus 15.0, IQR 5–15, p = 0.878). Receiver operator curve analysis of fibrosis SI compared to similarly located regions in control subjects showed an area under the curve of 0.82 (p = 0.002). A SI cutoff of 19 yielded a sensitivity of 75% and specificity of 86% in differentiating fibrosis from similarly located regions in control subjects. Conclusion LGE-MRI can differentiate CPFE from pure emphysema and may be a useful adjunct test to HRCT in patients with suspected CPFE.

Purpose Radiology is an important facet in the management of child health. Timely recognition of diagnoses on imaging is necessary to enable initiation of appropriate therapies. In this presentation, a wide selection of radiology signs are presented. These are a mixture of common signs which should not be missed, as well as rarer signs which can easily be misinterpreted1. The signs are presented primarily on plain film, although also using other modalities including ultrasound and CT2. The signs are displayed in such a way as to allow the viewer to quiz themselves prior to the answer being revealed. This will aid in future interpretation and understanding of paediatric imaging, for both experienced clinicians and newer trainees alike. Methods Can you differentiate the steeple sign from the silhouette sign? Can you tell a deep sulcus sign from a continuous diaphragm sign? Do you know the scimitar sign from the snowman sign? Can you decide if it’s Rigler’s sign or football sign? Only after the viewer has had the opportunity to interpret the image, will the answer and explanation be revealed. For each sign, a brief overview of the radiologic features are described, along with the diagnosis and any associations. The clinical relevance of each sign is discussed1,2. Conclusion A varied selection of paediatric radiologic signs are displayed, including neonatology, chest, cardiovascular, gastrointestinal, genitourinary, musculoskeletal and neurology. The complete list of signs will not be named in this abstract, to allow the viewer to interact with the presentation, without extensive prior knowledge. After interacting with this pictorial review, the viewer will have an increased understanding of multiple signs in paediatric radiology, which will help improve management of child health. References Arora, R & Kannikeswaran, N. Radiology callbacks to paediatric emergency department and their clinical impact. Pediatr Radiol 2018;48:1526. https://doi.org/10.1007/s00247-018-4176-y Cogley JR, O’Connor SC, Houshyar R, Al Dulaimy K. Emergent Pediatric US: What Every Radiologist Should Know. Radiographics 2012;32:651–665. https://doi.org/10.1148/rg.323115111

Haemoparasite infections and infestations with potential arthropod vectors were assessed in spiny mice Acomys dimidiatus from four wadis in the arid montane region of the southern Sinai in Egypt in late summer 2000. Five taxa of haemoparasites (Haemobartonella spp. 80%, Hepatozoon sp. 20.6%, Trypanosoma acomys 17.5%, Bartonella spp. 2.5% and Babesia sp. 1.9%) were recorded. Additionally, infections with two intestinal protozoa, Cryptosporidium cf. parvum and Giardia sp., were quantified, both with similar prevalence (17.0 and 17.6%, respectively). 17.9% of mice carried fleas (Parapulex chephrensis and Xenopsylla dipodilli) and 32.1% had lice (Polyplax oxyrrhyncha and Polyplax brachyrrhycha combined). Marked differences in the prevalence and abundance of infections were detected between the four wadis, particularly with respect to T. acomys, Hepatozoon sp. and fleas, which were largely aggregated in just two of the four sites (Wadis Gharaba and Tlah). In contrast, the intestinal protozoa were more common, and abundance was higher, in Wadi El Arbaein. Intrinsic factors also contributed to a variation in prevalence, with strong age-dependent increases in the prevalence and abundance of Hepatozoon sp., higher mean species richness, prevalence of Cr. cf. parvum, and abundance of Giardia sp. and Hepatozoon sp. in female mice. Haemobartonella spp. showed an age-dependent reduction in abundance and higher abundance among male mice. A weak association was found between the prevalence of T. acomys and its putative flea vector. The single extrinsic factor in the study, site of capture, was more important than the intrinsic factors in explaining variation in the prevalence and abundance of haemoparasites, intestinal protozoa and arthropod vectors. In the high mountains of southern Sinai, the parasite fauna of spiny mice is distinct in each wadi, and hence we expect the parasites to exert spatially different co-evolutionary pressures on their hosts, with a resultant variation in host life histories.

SUMMARY Since the publication of the mouse genome, attention has focused on the strains that were selected for sequencing. In this paper we report the results of experiments that characterized the response to infection with the murine gastrointestinal nematode Heligmosomoides polygyrus of eight new strains (A/J, C57BL/6, C3H, DBA/2, BALB/c, NIH, SJL and 129/J), in addition to the well-characterized CBA (poor responder) and SWR (strong responder) as our controls. We employed the repeated infection protocol (consisting of 7 superimposed doses of 125L3 each administered at weekly intervals, faecal egg counts in weeks 2, 4 and 6 and assessment of worm burdens in week 6) that was used successfully to identify quantitative trait loci for genes involved in resistance to H. polygyrus . SWR, SJL and NIH mice performed indistinguishably and are confirmed as strong responder strains to H. polygyrus . CBA, C3H and A/J mice all tolerated heavy infections and are assessed as poor responders. In contrast, DBA/2, 129/J and BALB/c mice performed variably between experiments, some tolerating heavy worm burdens comparable to those in poor responders, and some showing evidence of resistance, although only in one experiment with female 129/J females and one with female BALB/c was the pattern and extent of worm loss much like that in SWR mice. Because the genetic relationships between six of the strains exploited in this study are now well-understood, our results should enable analysis through single nucleotide polymorphisms and thereby provide more insight into the role of the genes that control resistance to H. polygyrus.

With the implementation of programs to control lymphatic filariasis and soil-transmitted helminths using broad spectrum anthelmintics, including albendazole and ivermectin, there is a need to develop an in vitro assay for detection of drug resistance. This report describes an in vitro assay for measuring the effects of ivermectin and benzimidazoles on the motility of larvae of the hookworm species Ancylostoma ceylanicum, A. caninum, and Necator americanus, and Strongyloides species including Strongyloides stercoralis, and S. ratti. A dose-response relationship was demonstrated with each of the parasite species, with distinct differences observed between the various species. In pilot field testing of the assay with N. americanus larvae recovered from human fecal samples, a dose-response relationship was observed with ivermectin. While the assay has demonstrated the ability to determine drug responsiveness, its usefulness in resistance detection will require correlation with the clinical outcome among individuals infected with parasite strains showing different drug sensitivities.

SUMMARY An experiment was carried out to compare the parasitological and immunological responses of SWR and CBA mice to trickle (repeated) infection with Heligmosomoides polygyrus. Male mice were given 125 L3 once per week and were killed in groups, together with naive control mice, weekly until week 8. Worm burdens accumulated in CBA, stabilizing in week 5 in excess of 400 worms and remaining high until week 8. In contrast in SWR worm burdens peaked in week 3 at a mean worm burden of 129 and then fell sharply so that by week 6, despite continuing re-infection, no more worms were recovered from these mice. SWR mice showed a marked mast cell and mMCP-1 response, peaking in weeks 2–3, whereas in CBA mice these responses were slower, and even at their height in week 8 still less intense than those in SWR mice. Both strains responded initially with a very similar goblet cell response, which declined in SWR mice as worms were eliminated, but was sustained in CBA mice until week 8. Serum TNFα concentrations were higher in SWR mice throughout the experiment. Infection elicited strong serological responses against adult and L4 antigens in both SWR and CBA mice, involving all the isotypes tested (IgG1, IgA and IgE). Anti-L3 responses were examined only for IgG1. However, only two responses differed significantly between the strains: the IgE response to L4 antigens was more intense in SWR mice, and interestingly and unexpectedly, the IgG1 response to adult worm antigens was more intense in CBA mice. These results reflect the activation of predominantly Th2-driven effector mechanisms, that may be associated with host-protective immunity developing under the trickle infection protocol exploited in these experiments.

The change in the relative acidities of the haloacetic acids on going from the gas phase to aqueous solution has been studied via ab initio calculations for the gas phase, the SCIPCM reaction field model for an aprotic polar solvent, and Monte Carlo statistical mechanics for aqueous solution. The relative gas phase acidities of acetic acid, the haloacetic acids and trifluoroacetic acid are well reproduced at the B3P86/6-311+G** and G2 levels of theory. The reaction field model reduced the relative acidities of fluoro- and bromoacetic acids to a value close to that found in aqueous solution, but it only reproduced half of the observed net effect of going from the gas phase to aqueous solution. Since the remainder of the solvent effect was probably due to hydrogen bonding, Monte Carlo calculations were carried out and they were in satisfactory accord with the aqueous solution pKa's.

Photoexcited cis-stilbene decays to the ground state on the femtosecond time scale, so fast that fluorescence is not generally observed and vibrational relaxation is incomplete. Decay can be accompanied by cis-trans isomerization about the double bond linking the two benzene rings and by electronic rearrangement to yield 4a,4b-dihydrophenanthrene (DHP). MMVB calculations suggest that there are several geometries (in addition to the perpendicular minimum) at which efficient decay can take place. In particular, a conical intersection has been documented along photocyclization reaction coordinate to DHP which may be reached with almost no barrier from a quinoid minimum. This intersection arises from interaction between the two benzene rings. Such a crossing is suggested in the recent experimental work of Yoshihara et al. (Petek, H.; Yoshihara, K.; Fujiwara, Y.; Lin, Z.; Penn, J. H.; Frederick, J. H. J. Phys. Chem. 1990, 94, 7539−7543) and must form part of a new mechanism for the decay of this well-studied m...

A hybrid GVB and CASSCF method is proposed, GVBCAS, in which a full CAS CI is performed amongst the active orbitals (the CAS part), and GVB type excitations are allowed amongst a set of GVB orbitals. We demonstrate that the computational effort required for the energy and gradients is little more than that for a CASSCF calculation with the strongly occupied GVB orbitals allocated to the inactive space, and substantially less than that for a full CASSCF in the space of active + GVB orbitals. The efficacy of the method is illustrated with an example.

The anomalous fluorescence of azuleneemission from S2 rather than S1was first recognized by Beer and Longuet-Higgins 40 years ago. Femtosecond laser studies and spectroscopic line width measurements have now established that radiationless decay from S1 to the ground state takes place in less than 1 ps. In this paper we show how such ultrafast S1 decay can be explained by relaxation through an unavoided S1/S0 crossing (i.e., a conical intersection). The S1 relaxation dynamics of azulene from its Franck−Condon structure are modeled semiclassically using a hybrid quantum-mechanical/force-field potential (MMVB) which reproduces the structure of the ab initio CASSCF potential energy surface. This simulation suggests that the S1 → S0 decay takes place in femtoseconds before a single oscillation through the crossing is completed.

Fine mapping of quantitative trait loci (QTL) associated with resistance to the gastrointestinal parasite Heligmosomoides polygyrus was achieved on F(6)/F(7) offspring (1076 mice) from resistant (SWR) and susceptible (CBA) mouse strains by selective genotyping (top and bottom 20% selected on total worm count in week 6). Fecal egg counts were recorded at weeks 2, 4, and 6, and the average was also analyzed. Blood packed cell volume in weeks 3 and 6 and five immunological traits (mucosal mast cell protease 1, granuloma score, IgG1 against adult worm, IgG1, and IgE to L4 antigen) were also recorded. On Chromosome 1 single-trait analyses identified a QTL with effects on eight traits located at about 24 cM on the F(2) mouse genome database (MGD) linkage map, with a 95% confidence interval (CI) of 20-32 cM established from a multitrait analysis. On Chromosome 17 a QTL with effects on nine traits was located at about 18 cM on the MGD map (CI 17.9-18.4 cM). Strong candidate genes for the QTL position on Chromosome 1 include genes known to be involved in regulating immune responses and on Chromosome 17 genes within the MHC, notably the Class II molecules and tumor necrosis factor.

We compared helminth communities in spiny mice (Acomys dimidiatus) from 4 wadis in the arid montane region of the southern Sinai in Egypt, in a 4-week period in late summer. Total helminth species richness was 14 (8 nematodes, 5 cestodes and 1 acanthocephalan) with 94% of mice carrying at least 1 species and an overall mean species richness of 1·85. The most prevalent parasites wereProtospirura muricola(47·8%) andDentostomella kuntzi(46·3%). One larval cestode,Joyeuxiella rossicum, represents a new host record. The helminth community was dominated by intestinal nematodes (88·7%) of which 58·2% were arthropod-transmitted heteroxenic species. At the component community level, 70% of the worms were recovered from mice in just two wadis (Gharaba and Tlah) and 48·6% of intestinal nematodes were from Wadi Gharaba. Although only 7 species of helminths were recorded from Wadi Gharaba, this site gave the highest Berger-Parker dominance index because ofP. muricola. P. muricolawas also dominant in Wadi El Arbaein whilstSyphacia minutawas the dominant species in Wadis Gebal and Tlah. At the infracommunity level, mean species richness and Brillouin's index of diversity were highest in Wadi Tlah and lowest in Wadi Gebal, and the former was age dependent. Whilst mice from different wadis differed in the nematodes that were most common, those from Wadi Gharaba carried the highest mean number of worms/mouse. The abundance ofP. muricolain particular varied markedly between sites: Wadi Gharaba was distinct as the site showing the highest mean worm burden whereas mice from Wadi Gebal were uninfected. None of the directly transmitted oxyuroid nematodes showed significant variation in abundance between wadis, or host sex or age classes. Overall, the single extrinsic factor in the study, site of capture, was more important than the intrinsic factors in explaining variation in helminth communities in the region. We conclude that in the high mountains of southern Sinai, each wadi is distinct in terms of its rodent parasites, and hence we expect spatially different coevolutionary pressures on their hosts, with resultant variation in life-histories.

Pathways involving possible conical intersections and radicaloid intermediates on the potential energy surface for the photocycloaddition of ethene to benzene have been studied using CASSCF geometr...