Canine pseudopregnancy: an evaluation of prevalence and current treatment protocols in the UK

Background: There is a dearth of literature on pseudopregnancy in the bitch, with only a few treatment-based studies published since the 1990s. Pseudopregnancy may be under-recognised in bitches and may account for a proportion of behavioural cases seen in veterinary practices including aggression. Little is known about commonly used treatments for overtly pseudopregnant bitches and it is possible that current regimes may not be prescribed for a sufficient duration to control any clinical signs including, physical and behavioural changes. To investigate current trends in diagnosis and treatment of canine pseudopregnancy, a postal survey was sent to 2000 randomly selected veterinary surgeons in UK veterinary practices. The questionnaire queried how often vets recognise cases of pseudopregnancy in spayed and entire bitches, which physical or behavioural signs are commonly recognised for diagnosis, and which management or treatment protocols are used. Results: The response rate was 19.8% (397/2000). Ninety-six percent of veterinary surgeons reported seeing pseudopregnant bitches showing behavioural changes without any physical changes within the last 12 months. Of those behavioural changes, collecting and mothering objects was the most frequently reported behavioural sign (96%). Ninety-seven percent of vets had seen aggression in pseudopregnant bitches. Nevertheless, only 52% of vets routinely asked owners about behavioural changes during consultations. Forty-nine percent of respondents reported seeing pseudopregnancy in spayed bitches. The most commonly reported physical sign was enlarged mammary glands and/or milk production (89%). Treatment options varied (surgical, medical or none) and depended on duration and severity of physical and behavioural signs, owners’ preference, cost, concurrent disease, drug availability and previous history. Conclusions: This is the largest epidemiological study of canine pseudopregnancy in the UK. The prevalence and severity of clinical signs in dogs with pseudopregnancy are variable and possibly under-estimated. Dogs with overt pseudopregnancy experience diverse physical and behavioural changes and information on standard treatment protocols are lacking. Although, progress on our understanding of diagnosis and treatment of pseudopregnancy in spayed and entire bitches has been made, further studies are warranted

Polyploidy in non-neoplastic tissues.

AIM--To investigate the prevalence and amount of polyploidy in fine needle aspiration specimens of the liver, urinary cytospin preparations, and cytospin preparations from pleural and peritoneal fluid. METHODS--Cells from 44 liver smears, 48 urine specimens, and 46 pleural and peritoneal aspirations were examined. After Feulgen restaining the DNA content of 100 randomly selected nuclei was determined using a TAS-plus image analysis system, combined with an automated microscope. RESULTS--Polyploidy was observed up to 16c in the liver, and up to 8c in urothelium and mesothelium. Sixty eight per cent of the liver aspirates contained polyploid nuclei. The rate in urothelium was 20.8% and in mesothelium 6.5%. CONCLUSIONS--Polyploidy in the liver may be interpreted as being associated with tissue differentiation, but the findings in urothelium and mesothelium remain of unknown importance

Evaluation of waste heat recovery technologies for the cement industry

Cement is the world’s most widely used construction material. In 2019, global production amounted to 4086 MT, of which Colombia contributed 12.59 MT. The main component of cement is Clinker and it appears as an intermediate product in the manufacturing process that is produced in a kiln system at sintering temperatures. Such a process exhibits high environmental impacts due to both elevated emissions of Carbon Dioxide and fuel consumption and it is inherently prone to thermal inefficiencies, as heat losses to the surroundings, because of the large flow rates and high temperatures. In this work, the waste heat obtained from the cooling of a high-temperature gas effluent from the rotary kiln in a Colombian cement plant is analysed for its potential use either to dry wet raw material (limestone) or to generate electricity through an ORC. Material, energy and exergy balances for the steady-state were assisted with simulations in Aspen Plus V.10 software. Exergo-economics analysis followed the traditional approach using the net present value (NPV) of the investment as decision criteria. To achieve a holistic view of the waste heat recovery scenario a sensitivity analysis is carried out varying the outlet temperatures of the hot gases for various working fluids in the ORC. Results showed that the best alternative, NPV = 0.37 MUSD at market conditions of electricity and fuel sale price, delivers a maximum of 3.77 MW of electricity with a thermal efficiency of 15.96% and an exergy efficiency of 37.52% using Cyclo-Pentane as working fluid. None of the dryer units attained a positive NPV and were discarded. However, the highest moisture reduction in the solids stream was 5.67% at T = 120∘C. The option of placing a drying unit immediately after an ORC to completely cool down the gases was economically analysed for ORC cases with best NPV, T= 150∘C and T = 180∘C. But no substantial improvement was found over using the ORC alone. The possibility to improve the simple ORC performance is explored through the inclusion of an internal heat exchanger, such recuperated cycle outperforms its simpler configuration in terms of thermal and economic performance delivering 4.1 MW of net work with an NPV = 0.42 MUSD, a rate of return of 15.58% and a payback time of PB = 6.07 years. This is 8.75% more work with 13.51% better economic performance than the simple ORC.The Royal Academy of Engineerin