Do female dingo–dog hybrids breed like dingoes or dogs?

2017 ◽  
Vol 65 (2) ◽  
pp. 112 ◽  
Author(s):  
Marina S. Cursino ◽  
Lana Harriott ◽  
Benjamin L. Allen ◽  
Matthew Gentle ◽  
Luke K.-P. Leung
Keyword(s):  
Corpus Luteum ◽  
Urban Areas ◽  
Late Summer ◽  
Follicular Phase ◽  
Domestic Dogs ◽  
Effective Management ◽  
Histological Features ◽  
Future Studies ◽  
Breeding Seasonality ◽  
Reproductive Cycles

Hybridisation between animals that breed once (e.g. dingoes) and twice (e.g. domestic dogs) annually may produce offspring that breed either way. This question was investigated by determining the breeding seasonality of female dingo–dog hybrids in south-east Queensland, Australia, through evaluating macroscopic and histological features of 71 female reproductive tracts. All animals were sourced from urban areas where levels of hybridisation are generally high. Most animals trapped in summer were pups less than 6 months of age. A peak of uterus diameter and weight coincided with a peak of corpus luteum in winter. The follicular phase was characterised by growing follicles, ~1–3 mm wide, in late summer and autumn. Only two of the animals (1.4%) showed out-of-season reproductive cycles: one was found with corpus luteum in summer and another in autumn. Our data clearly show that hybrids have a single annual breeding season in winter, exhibiting the same breeding seasonality as dingoes. Our findings are similar to those found in the New Guinea singing dog. Future studies should be conducted to understand and exploit the mechanism and drivers of the breeding seasonality of dingo–dog hybrids to develop more effective management of their populations.

scholarly journals Implications of Autonomous Vehicles for Accessibility and Transport Equity: A Framework Based on Literature

2021 ◽  
Vol 13 (8) ◽  
pp. 4448
Author(s):  
Alberto Dianin ◽  
Elisa Ravazzoli ◽  
Georg Hauger
Keyword(s):  
Conceptual Model ◽  
Transport System ◽  
Urban Areas ◽  
Autonomous Vehicles ◽  
Scientific Literature ◽  
Social Groups ◽  
Future Studies ◽  
Social Accessibility ◽  
The Relationship

Increasing accessibility and balancing its distribution across space and social groups are two fundamental goals to make transport more sustainable and equitable. In the next decades, autonomous vehicles (AVs) could significantly transform the transport system, influencing accessibility and transport equity. In particular, depending on the assumed features of AVs (e.g., private or collective) and the considered spatial, social, and regulative context (e.g., rural or urban areas), impacts may be very different. Nevertheless, research in this field is still limited, and the relationship between AV assumptions and accessibility impacts is still partially unclear. This paper aims to provide a framework of the key and emerging aspects related to the implications of AVs for accessibility and transport equity. To set this framework, we perform an analysis of the scientific literature based on a conceptual model describing the implications of AVs for the distribution of accessibility across space and social groups. We recognize four main expected impacts of AVs on accessibility: (1) accessibility polarization, (2) accessibility sprawl, (3) exacerbation of social accessibility inequities, and (4) alleviation of social accessibility inequities. These impacts are described and analyzed in relation to the main AV assumptions expected to trigger them through different mechanisms. Based on the results, some recommendations for future studies intending to focus on the relation between AVs, accessibility, and transport equity are provided.

scholarly journals Temporal–Spatial Patterns of Relative Humidity and the Urban Dryness Island Effect in Beijing City

2017 ◽  
Vol 56 (8) ◽  
pp. 2221-2237 ◽  
Author(s):  
Ping Yang ◽  
Guoyu Ren ◽  
Wei Hou
Keyword(s):  
Relative Humidity ◽  
Urban Areas ◽  
Late Summer ◽  
Beijing City ◽  
Near Surface ◽  
Suburban Areas ◽  
Island Effect ◽  
Different Seasons ◽  
Autumn And Winter ◽  
Beijing China

AbstractHourly datasets obtained by automatic weather stations in Beijing, China, are developed and employed to analyze the spatial and temporal characteristics of relative humidity (RH) and urban dryness island intensity (UDII) over built-up areas. A total of 36 stations inside the sixth ring road are considered as urban sites, while six stations in suburban belts surrounding the built-up areas are taken as reference sites. Results show that the RH is obviously smaller in urban areas than in suburban areas, indicating the effect of urbanization on near-surface atmospheric moisture and RH. A further analysis of relations between RH and temperature on varied time scales shows that the variations in RH in the urban areas are not due solely to changes in temperature. The annual and seasonal mean UDII are high in central urban areas, with the strongest UDII values occurring in autumn and the weakest values occurring in spring. The diurnal UDII variations are characterized by a steadily strong UDII stage from 2000 to 0800 LT and a minimum at 1500 or 1600 LT. The rapid shifts of UDII from high (low) to low (high) occur during the periods 0800–1600 LT (1600–2000 LT). The occurrence time of the peaks varies among different seasons: the peaks appear at 0700, 2100, 2000, and 0800 LT for spring, summer, autumn, and winter, respectively. Further analysis shows that large UDII values appear in the evenings and early nights in late summer and early to midautumn and that low UDII values mainly occur in the afternoon hours of spring, winter, and late autumn.

Simulation of the Cooking Organic Aerosol Concentration Variability in an Urban Area

2021 ◽  
Author(s):  
Evangelia Siouti ◽  
Ksakousti Skyllakou ◽  
Ioannis Kioutsioukis ◽  
Giancarlo Ciarelli ◽  
Spyros N. Pandis
Keyword(s):  
Urban Area ◽  
Urban Areas ◽  
Temporal Distribution ◽  
Late Summer ◽  
Field Studies ◽  
Organic Aerosol ◽  
Basis Set ◽  
Cooking Times ◽  
The City ◽  
Lunch Time

<p>Cooking operations can be an important fine PM source for urban areas. Cooking emissions are a source of pollution that has been often ignored and are not included or are seriously underestimated in urban emission inventories. However, several field studies in cities all over Europe suggest that cooking organic aerosol (COA) can be an important component of the total organic PM. In this study we propose and evaluate a methodology for the simulation of the COA concentration and its variability in space and time in an urban area. The city of Patras, the third biggest in Greece is used for this first application for a typical late summer period. The spatial distribution of COA emissions is based on the exact location of restaurants and grills, while the emissions on the meat consumption in Greece. We estimated COA emissions of 150 kg d<sup>-1</sup> that corresponds to 0.6 g d<sup>-1</sup> per person. The temporal distribution of COA was based on the known cooking times and the results of the past field studies in the area. Half of the daily COA is emitted during dinner time (21:00-0:00 LT), while approximately 25% during lunch time (13:00-16:00 LT). The COA is simulated using the Volatility Basis Set with a volatility distribution measured in the laboratory and is treated as semivolatile and reactive. The maximum average COA concentration during the simulation period is predicted to be 1.3 μg m<sup>-3</sup> in a mainly pedestrian area with a high density of restaurants. Peak hourly COA concentrations in this area exceed 10 μg m<sup>-3</sup> during several nights. The local production of secondary COA is predicted to be slow and it represents just a few percent of the total COA.</p><p> </p>

scholarly journals Operative Monographies: Development of a New Tool for the Effective Management of Landslide Risks

Geosciences ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 485 ◽  
Author(s):  
Daniele Giordan ◽  
Martina Cignetti ◽  
Aleksandra Wrzesniak ◽  
Paolo Allasia ◽  
Davide Bertolo
Keyword(s):  
Urban Areas ◽  
Interdisciplinary Approach ◽  
Civil Aviation ◽  
Landslide Risk ◽  
Effective Management ◽  
Standard Format ◽  
Hazard Management ◽  
Efficient Management ◽  
Long Time ◽  
Nw Italy

Active landslide risk assessment and management are primarily based on the availability of dedicated studies and monitoring activities. The establishment of decision support for the efficient management of active landslides threatening urban areas is a worthwhile contribution. Nowadays, consistent information about major landslide hazards is obtained through an interdisciplinary approach, consisting of field survey data and long-time monitoring, with the creation of a high populated dataset. Nevertheless, the large number and variety of acquired data can generate some criticalities in their management. Data fragmentation and a missing standard format of the data should represent a serious hitch in landslide hazard management. A good organization in a standard format can be a good operative solution. Based on standardized approaches such as the ICAO (International Civil Aviation Organization), we developed a standard document called operative monography. This document summarizes all available information by organizing monitoring data and identifying possible lacks. We tested this approach in the Aosta Valley Region (NW Italy) on five different slow moving landslides monitored for twenty years. The critical analysis of the available dataset modifies a simple sequence of information in a more complex document, adoptable by local and national authorities for a more effective management of active landslides.

Source of ovarian inhibin secretion during the oestrous cycle of the sheep

1989 ◽  
Vol 123 (2) ◽  
pp. 181-188 ◽  
Author(s):  
G. E. Mann ◽  
A. S. McNeilly ◽  
D. T. Baird
Keyword(s):  
Corpus Luteum ◽  
Luteal Phase ◽  
Venous Blood ◽  
Contralateral Side ◽  
Follicular Phase ◽  
Oestrous Cycle ◽  
Secretion Rate ◽  
Antral Follicles ◽  
Luteal Tissue

ABSTRACT The source of inhibin secretion by the ovary in the sheep at different stages of the oestrous cycle was investigated by in-vivo cannulation of the ovarian veins. Twenty-four Scottish Blackface ewes were allocated to four groups of six ewes, i.e. those operated on during the luteal phase (day 10), and those operated on during the follicular phase 24–30, 36 and 60 h following an injection of 125 μg cloprostenol on day 10 of the luteal phase. Samples of jugular and timed ovarian venous blood were collected under anaesthesia before and after enucleation of the corpus luteum. Ovaries were then removed and follicles dissected out. Following injection of cloprostenol, luteal regression occurred as indicated by a fall in the secretion of progesterone. The concentration of inhibin in jugular venous plasma and its ovarian secretion rate were similar at all stages of the follicular phase and during the luteal phase. In contrast, the secretion rate of oestradiol rose from 2·68 ±0·73 pmol/min during the luteal phase to 8·70± 2·24 pmol/min 24 h after injection of cloprostenol (P<0·05). Following enucleation of the corpus luteum the secretion rate of progesterone fell from 809 ± 270 pmol/min to 86 ± 30 pmol/min (P<0·001). There was also a smaller, artifactual fall in the secretion rate of oestradiol following enucleation of the corpus luteum, which was of similar size to a fall seen in the secretion rate of inhibin. This resulted in a significant (P<0·001) fall in the ratio of progesterone to inhibin, while the oestradiol to inhibin ratio remained unchanged. The secretion rate of inhibin from ovaries containing luteal tissue was similar to that from the contralateral side without luteal tissue (1·41±0·30 compared with 1·32±0·30 ng/min), while ovaries with large antral follicles secreted significantly (P< 0·001) more inhibin than those with no follicles ≥3 mm (2·28 ± 0·36 compared with 0·25 ±0·06 ng/min). From these results we conclude that, in the sheep, large antral follicles are responsible for most, if not all, the secretion of inhibin by the ovary at all stages of the oestrous cycle, and that the corpus luteum secretes little or no immunoactive or bioactive inhibin. Due to the fact that, unlike inhibin, the secretion rate of oestradiol rises during the follicular phase of the cycle, when the concentration of FSH is suppressed, it seems likely that oestradiol rather than inhibin is the major ovarian factor modulating the change in FSH secretion seen at this stage of the oestrous cycle. Journal of Endocrinology (1989) 123, 181–188

scholarly journals Aerosol seasonal variations over urban sites in Ukraine and Belarus according to AERONET and POLDER measurements

2013 ◽  
Vol 6 (6) ◽  
pp. 10731-10759 ◽  
Author(s):  
G. Milinevsky ◽  
V. Danylevsky ◽  
V. Bovchaliuk ◽  
A. Bovchaliuk ◽  
Ph. Goloub ◽  
...  
Keyword(s):  
Optical Thickness ◽  
Seasonal Variations ◽  
Urban Areas ◽  
Late Summer ◽  
Single Scattering ◽  
Aerosol Optical Thickness ◽  
Saharan Dust ◽  
Coarse Mode ◽  
Modal Radius ◽  
Urban Sites

Abstract. The paper presents an investigation of aerosol seasonal variations in several urban sites in the East European region. Our analysis of seasonal variations of optical and physical aerosol parameters is based on the sun-photometer 2008–2012 data from three urban ground-based AERONET sites in Ukraine (Kyiv, Kyiv-AO, and Lugansk) and one site in Belarus (Minsk), as well as on satellite POLDER instrument data for urban areas in Ukraine. Aerosol amount and optical thickness values exhibit peaks in the spring (April–May) and late summer (August), whereas minimum values are seen in late autumn over the Kyiv and Minsk sites. The results show that aerosol fine mode particles are most frequently detected during the spring and late summer seasons. The seasonal variation similarity in the two regions points to the resemblance in basic aerosol sources which are closely related to properties of aerosol particles. However the aerosol amount and properties change noticeably from year to year and from region to region. The analysis of seasonal aerosol optical thickness variations over the urban sites in the eastern and western parts of Ukraine according to both ground-based and POLDER data exhibits the same traits. In particular, over Kyiv, the values of the Angstrom exponent are lower in April of 2011 than in 2009 and 2010, while aerosol optical thickness values are almost the same, which can be explained by an increase in the amount of coarse mode particles in the atmosphere, such as Saharan dust. Moreover, the coarse mode particles prevailed over suburbs and the center of Kyiv during a third of all available days of observation in 2012. In general, the fine and coarse mode particles' modal radii averaged over 2008–2012 range from 0.1 to 0.2 μm and 2 to 5 μm, respectively, during the period from April to September. The single scattering albedo and refractive index values of these particles correspond to a mix of urban-industrial, biomass burning, and dust aerosols. In addition, strongly absorbing particles were observed in the period from October to March, and the modal radius of fine and coarse mode particles changed from month to month widely.

scholarly journals Effectiveness of Hydraulic and Hydrologic Parameters in Assessing Storm System Flooding

2018 ◽  
Vol 2018 ◽  
pp. 1-17 ◽  
Author(s):  
Basim K. Nile
Keyword(s):  
Urban Areas ◽  
Water System ◽  
Storm Water ◽  
Effective Management ◽  
Cross Sectional ◽  
Sewer Systems ◽  
Physically Based ◽  
Physically Based Models ◽  
Runoff Discharge ◽  
Sensitive Parameters

Storm sewer systems face many challenges in urban areas, in particular those systems which are old and surpassing their design period. This study has used data from an urbanized, subcatchment covering 360 ha of dead run watershed in the Alkadeer district, Karbala, Iraq. Physically based models, Autodesk Storm and Sanitary Analysis (ASSA) and multiple nonlinear regression (MNLR), were applied. Hydrology data from 1980 to 2013 were inputted and examined over three scenarios. The results indicated that significant increase in peak flooding was produced by an increase in discharge values which may occur through a higher rainfall intensity. The model was examined and new equations were developed that may help us to better understand the hydraulic and hydrologic simulations that are identified as having the potential to better protect the environment against sudden rainfall intensities. The ratio of area of subcatchment to cross-sectional area of a pipe (Ac/Ap), the ratio of slope of subcatchment to slope of a pipe (Sc/Sp), and the ratio of velocity in subcatchment to velocity in a pipe (Vc/Vp) were the most sensitive parameters informing the ratio of runoff discharge of a subcatchment pipe discharge (Qc/Qp). This study suggests that a more effective management of the storm water system under critical circumstances could be achieved by limiting the above parameters and this increases the efficiency of storm water facilities.

Observations on the Reproductive-Biology and Anatomy of Rhinolophus-Megaphyllus (Chiroptera, Rhinolophidae) in Eastern Australia

1992 ◽  
Vol 40 (5) ◽  
pp. 533 ◽  
Author(s):  
PH Krutzsch ◽  
RA Young ◽  
EG Crichton
Keyword(s):  
Corpus Luteum ◽  
Late Summer ◽  
Sperm Storage ◽  
Epididymal Sperm ◽  
Male And Female ◽  
Vaginal Plug ◽  
Eastern Australia ◽  
Accessory Sex Organs ◽  
Reproductive Events

The anatomy and chronology of reproductive events in male and female Rhinolophus megaphyllus from eastern Australia (27-32-degrees-S.) is discussed. Rhinolophus megaphyllus was monoestrous and monotocous. A delay of several months occurs between the delivery of spermatozoa to the caudae epididymides (late summer/early autumn) and copulation/ovulation/conception (winter), which occur towards the termination of the spermatogenic cycle. There is no storage of sperm in female tracts prior to ovulation but epididymal sperm storage persists beyond the time of birth (late spring). Male, but not female, readiness to initiate reproduction prior to the onset of winter, places this species in an 'intermediate' position with features of both temperate and tropical chiropteran reproductive cycle patterns. The presence of an extroverted corpus luteum in the female and of a complement of accessory sex organs in the male are normal glandular features for members of this chiropteran family. The role of the urethral gland is unknown; however, since there is no vaginal plug, its products apparently do not coagulate in the vagina in this species following insemination.

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