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Event classification is a common task in gamma-ray astrophysics. It can be treated with rapidly-advancing machine learning algorithms, which have the potential to outperform traditional analysis methods. However, a major challenge for machine learning models is extracting reliably labelled training examples from real data. Citizen science offers a promising approach to tackle this challenge. We present "Muon Hunter", a citizen science project hosted on the Zooniverse platform, where VERITAS data are classified multiple times by individual users in order to select and parameterize muon events, a product from cosmic ray induced showers. We use this dataset to train and validate a convolutional neural-network model to identify muon events for use in monitoring and calibration. The results of this work and our experience of using the Zooniverse are presented., Comment: 8 pages, 3 figures, in Proceedings of the 35th International Cosmic Ray Conference (ICRC 2017), Busan, South Korea

Wild Zimbabwe Ostriches Struthio camelus were studied during four successive years. Information on breeding seasons and laying patterns was compared with that of domesticated South African hybrid Ostriches in Bophuthatswana. In wild populations laying occurred mainly from July to December or early January, while domesticated birds continued until at least the end of February. Domesticated birds normally laid about 16 eggs in succession, one every second day. There was marked synchronisation of laying and the middle of each successive peak in egg production was about 6 weeks from the preceding peak. Wild birds laid up to eight eggs in any one nest, and normally clutches were contributed by three females, the average combined clutch being 12 or 13 per nest. Circumstantial evidence suggests that individual females may lay in more than one nest during a single laying sequence. Comparisons between rainfall patterns and laying rhythms proved inconclusive.

We present the discovery of three new transiting giant planets, first detected with the WASP telescopes, and establish their planetary nature with follow up spectroscopy and ground-based photometric lightcurves. WASP-92 is an F7 star, with a moderately inflated planet orbiting with a period of 2.17 days, which has $R_p = 1.461 \pm 0.077 R_{\rm J}$ and $M_p = 0.805 \pm 0.068 M_{\rm J}$. WASP-93b orbits its F4 host star every 2.73 days and has $R_p = 1.597 \pm 0.077 R_{\rm J}$ and $M_p = 1.47 \pm 0.029 M_{\rm J}$. WASP-118b also has a hot host star (F6) and is moderately inflated, where $R_p = 1.440 \pm 0.036 R_{\rm J}$ and $M_p = 0.513 \pm 0.041 M_{\rm J}$ and the planet has an orbital period of 4.05 days. They are bright targets (V = 13.18, 10.97 and 11.07 respectively) ideal for further characterisation work, particularly WASP-118b, which is being observed by K2 as part of campaign 8. WASP-93b is expected to be tidally migrating outwards, which is divergent from the tidal behaviour of the majority of hot Jupiters discovered., Comment: 14 pages, 10 figures; submitted to MNRAS

We report the discovery and characterisation of a deeply eclipsing AM CVn-system, Gaia14aae (= ASSASN-14cn). Gaia14aae was identified independently by the All-Sky Automated Survey for Supernovae (ASAS-SN; Shappee et al. 2014) and by the Gaia Science Alerts project, during two separate outbursts. A third outburst is seen in archival Pan-STARRS-1 (PS1; Schlafly et al. 2012; Tonry et al. 2012; Magnier et al. 2013) and ASAS-SN data. Spectroscopy reveals a hot, hydrogen-deficient spectrum with clear double-peaked emission lines, consistent with an accreting double degenerate classification. We use follow-up photometry to constrain the orbital parameters of the system. We find an orbital period of 49.71 min, which places Gaia14aae at the long period extremum of the outbursting AM CVn period distribution. Gaia14aae is dominated by the light from its accreting white dwarf. Assuming an orbital inclination of 90 degrees for the binary system, the contact phases of the white dwarf lead to lower limits of 0.78 M solar and 0.015 M solar on the masses of the accretor and donor respectively and a lower limit on the mass ratio of 0.019. Gaia14aae is only the third eclipsing AM CVn star known, and the first in which the WD is totally eclipsed. Using a helium WD model, we estimate the accretor's effective temperature to be 12900+-200 K. The three out-burst events occurred within 4 months of each other, while no other outburst activity is seen in the previous 8 years of Catalina Real-time Transient Survey (CRTS; Drake et al. 2009), Pan-STARRS-1 and ASAS-SN data. This suggests that these events might be rebrightenings of the first outburst rather than individual events., Comment: 9

Summary Boshoff, A.F., Palmer, N.G., Avery, G., Davies, R.A.G. & Jarvis, M.J.F. 1991. Biogeoraphical and toporaphical variation in the prey of the Black Eagle in the Cape Province, South Africa. Ostrich 62: 58–72. Prey remains collected at or near Black Eagle Aquilu verreauxii nest sites in the Cape Province, South Africa, were analysed according to frequency of occurrence of prey scies in the samples. A total of 5748 prey individuals, collected from 73 sites, was analysed according to tree biome groups and four nest site types. The Rock Hyrax Procuvia capensis is the dominant prey species, but the eagles' diet sctrum vanestypes. The according to its availability. Indices of species richness and diversity of the prey are inverser correlated with the proportion of the prey contributed by P. capenis, which in turn is determined by topography and vegetation. Biome has a greater influence on the indices than has nest site type. The age structure of the P. capensis prey remains closely reflects the juvenile: s...

The Gompertz equation was used to compute growth curves for three groups of ostriches (Struthio camelus), from Oudtshoorn in South Africa, the Namib desert in Namibia and from Zimbabwe. All were reared under typical intensive farm conditions with ad libitum feeding. There were no significant differences in mature mass between regions but the maximum daily weight gain for males occurred later (day 163) for Oudtshoorn birds, compared with day 121 for Namibian and day 92 for Zimbabwean. Oudtshoorn females reached maximum rate of gain on day 175 compared with day 115 for Namibian and day 114 for Zimbabwean. Comparisons might prove important when planning programmes for the genetic improvement of commercial flocks, but possible influences of food composition and environment should be investigated.

Summary Jarvis, M. J. F., Keffen, R. H. & Jarvis, C. 1985. Some physical requirementsfor Ostrich egg incubation. Ostrich 56: 42–51. Eggs from wild and domesticated Ostriches Struthio camelus australis were studied to determine temperature and humidity requirements for successful incubation. Wild eggs in Zimbabwe included some collected and incubated artificially, and others that were naturally incubated until just before hatching. Egg-weight losses during incubation were measured. The eggs artificially incubated at 35 °C to 36°C and 40–42% relative humidity, lost nearly the same weight as did eggs in naturally incubated nests. Comparisons were made between the wild eggs and chicks, and those from domesticated hybrid-strain Ostriches in Bophuthatswana. The discussion outlines some of the remaining problems associated with Ostrich egg incubation.

The application of pattern recognition techniques to manufacturing processes is a rapidly developing technology. Automatic verification of the quality of printed wiring boards (PWB's) using pattern recognition techniques is one potential application in this field. Qualitatively, this problem is finding small, irregular features in an environment of complicated, but larger and well-defined geometric features. In addition to the basic pattern recognition task, stringent performance requirements, both for throughput and accuracy, must be met if actual production usage is expected. The method employed in this study is based on characterizing 5 × 5 or 7 × 7 element binary patterns derived from the class of PWB's being inspected as good or defective. A database of 80 512 × 512 element images of PWB's was constructed and used to determine the number of unique patterns and their rates of occurrence. The major experimental result of this study is that less than 500 of the possible (15/16)224 5 × 5 patterns are needed to describe all the border containing patterns in the 80 images. It is also apparent that more patterns would be required if the training database was larger. The small number of patterns needed to represent virtually all of the normal border patterns suggests a two-stage inspection strategy. In the first stage, each border pattern from the PWB being inspected is compared to a previously prepared list.

Summary Jarvis, M. J. F., Currie, M. H. & Palmer, N. G. 1980. Food of Crowned Eagles in the Cape Province, South Africa. Ostrich 51:215-218. Bones were collected from 16 nests of Crowned Eagles Polemaetus coronatus and three of these nests were observed from hides. The bone remains give some idea of the spectrum of prey animals taken and reveal differences from nest to nest. A total of 598 distinct prey animals were identified. The Rock Hyrax Procavia capensis formed 42%, Blue Duiker Cephahphus monticola 16%, juvenile Bushbuck Tragelaphus scriptus 12% Vervet Monkeys Cercopithecus pygerytkrus 8% and juvenile bovids 6% Although 15 out of 16 nests showed Rock Hyrax remains, Blue Duiker were found at only 10 nests and juvenile Bushbuck at nine. Juvenile bovids were mainly domestic lambs and came from 10 nests, but never comprised more than 16% of the total prey animals at any one nest. Some farmers have found ways of stopping predation on lambs without having to destroy the eagles.

Summary Keffen, R. H. & Jarvis, M. J. F. 1984. Some measurements relating to Ostrich eggs. Ostrich 55:182-187. Eggs from wild Zimbabwean Ostriches Struthio camelus australis and domesticated South African hybrid birds, were compared. Formulae were tested to determine their accuracy when used to calculate egg weights, surface area and density. Calculated values were compared with some actual measurements. The main motivation for the study was the need to calculate fresh egg weights of wild Ostriches, as an aid to determining weight loss during incubation under natural conditions. Eggs from wild birds were, on average, smaller than those from domesticated birds, even though the wild adults were larger than domesticated birds. However, newly batched chicks from hybrid eggs weighed less than those from wild eggs.

Summary Jarvis, M. J. F. & Currie, M. H. 1979. Breeding of captive Knysna and Purplecrested Louries. Ostrich 50:38-44. Knysna Louries Tauraco corythaix and Purplecrested Louries T. porphyreolophus were studied in captivity to determine food requirements and feeding habits, clutch size, egg measurements, incubation periods, as well as the nestling period, anatomical and behavioural development of chicks, and aspects of parental behaviour.

350 children treated for cleft palate at the children's Hospital of Cape Town, have been followed by periodic examination at the Audiological Unit of the Groote Schuur Hospital over a period of 7 years. The incidence of middle ear disease has been found to be over 60%. Its frequency and severity has been assessed and the progress of the hearing loss in individual cases during childhood years has been followed in many instances. The causation is discussed and methods of management described. The incidence is correlated with the type of operation performed for cleft repair and with the age at which it was done.

(1969). INTERACTIONS BETWEEN MAN AND THE SOUTH AFRICAN GANNET SULA CAPENSIS. Ostrich: Vol. 40, No. sup1, pp. 497-513.

Two direct branches of the brachiocephalic artery are frequently present in the dog. These are described in 33 dogs and their incidence recorded. One supplies the lower cervical trachea and esophagus and the other the thymus gland and sometimes the pericardium. Suggested names are “Tracheoesophageal” and “Thymopericardial” branches of the brachiocephalic. The embryology of the blood vessels of the esophagus is discussed and the identification of the tracheoesophageal with a secondary anastomotic vessel is considered most likely. Occasional branches from the brachiocephalic artery in man are reviewed. The Arteria Thyroidea Ima seems to bear the closest relationship to this vessel described in the dog. The value of this study in relation to heart-lung preparations and to experimental surgery of the esophagus is suggested.

With heart-lung preparations of ten large dogs, heart sounds were recorded from the exposed right ventricle simultaneously with records of venous pulsation, electrocardiogram, and arterial blood pressure. Arterial pressure readings were corrected to allow for the drop in pressure which occurs in the preparation between the aorta and external circuit. Venous pressure was altered by raising or lowering the venous reservoir, arterial pressure by altering resistance to flow through the external circuit. Heart rates were very constant except for gradual slowing during the experiment. Increasing the venous pressure increased the cardiac output and the amplitude of the first heart sound; the amplitude of the second sound usually diminished. Increasing the arterial pressure from low to hypertensive levels increased the amplitude of the first heart sound; the amplitude of the second sound increased to an aortic pressure of 120–140 mm Hg, beyond which it diminished. The third and fourth heart sounds were not recorded sufficiently frequently to merit analysis.

A number of bird counts have been made on Lake McIlwaine and its shoreline. This paper does not attempt a comprehensive checklist but rather it selects some species and traces changes in their abundance as the lake vegetation and nutrient levels have altered.

A system, FOCAS (Faint Object Classification and Analysis System), designed to automatically detect and catalog stellar and galactic images on photographic plates is described. FOCAS was designed and is used to find all objects brighter than a limiting magnitude (24th on nitrogen baked IIIaJ plates exposed for one hour on the KPNO 4m telescope) and classify each image as stellar (nonresolved) or galactic (resolved). An important task in the implementation of this system is to verify that it performs as designed and to establish its limitations. The following internal tests were made to establish confidence in the automated cataloging system. Processing and comparing objects from two plates of the same field yields information about object detection efficiency and classification consistency. Processing synthesized dim stellar images provides detection efficiency information. Classification of synthesized stellar and galactic images gives information regarding classification accuracy. Processing a uniformly fogged plate establishes the magnitude where emulsion irregularities begin being detected as images. Comparison of FOCAS results with deeper CCD and video camera images corroborates these internal tests.

Experiences with 147 laryngectomies, 49 with en bloc neck dissection, are presented. One patient died, and 36 suffered postoperative complications serious enough to delay rehabilitation and to prolong hospitalisation.

Munro (1966) defined the shoreline habitats of Lake McIlwaine in terms of the presence or absence of aquatic macrophytes, and the major species of macrophyte where the plants were present. Relatively few areas of the lake shore were free of macrophytes (Fig. 13), most of these being granite outcrops or steep sand and gravel shores in the main lake basin. Munro (1966) identified the major species of aquatic plants in the impoundment as Phragmites sp., Typha sp., Aponogeton sp., and Nymphea caerula. In the more riverine upper reaches of the lake, he noted extensive beds of Polygonum senegalense which extended some 30 to 40 m out into the lake. These stands were often associated with Lagarosiphon major, forming dense mats, although the latter was also distributed through other areas of the lake.

A system for detecting and classifying images on astronomical plates is described. In particular, the very faint and barely resolved images of 24th magnitude galaxies are shown to be detectable and distinguishable from stellar images of similar brightness. The algorithms and other implementation con-siderations used in the construction of FOCAS are given. Detection and classification at 24th magnitude is achieved with N2 presensitized IIIaJ plates exposed for one hour in the KPNO 4-m telescope prime focus camera. For a digital 6000x6000 pixel image made from the central square area 37' on a side approximately 16000 objects are found to 24.7 mag on such plates. Since the resulting catalog of objects is 3 or 4 magnitudes deeper than existing surveys a variety of internal tests must be used to assess the accuracy and completeness of the list of objects. The tests and simulations made to support these claims are also discussed.© (1979) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.