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Additional file 1: Table S1. Reference DNA samples for Leishmania and sand fly species used in the study. Table S2. Sand flies and Leishmania GenBank accession numbers used in this study for primer designing. Table S3. The virtual probe sequences used for detection and identification of sand flies and Leishmania parasites.

This paper investigates the theoretical energy outlook of a supermarkets in Stockholm, as well as the energy efficiency of its refrigeration unit. The refrigeration unit is a CO2 trans-critical booster system with air conditioning and geothermal storage integration into the medium temperature level. This stage is operated under overfeed conditions (zero internal superheating) thanks to liquid ejectors. On the other hand, the freezers operate under direct expansion with an optimum superheat. The supermarket is heated up by reclaimed heat from the refrigeration unit. Two heat exchangers are integrated after the high-stage compressors where water is heated for tap water and space heating. The simulation is done for a supermarket in the design stage as part of a study that will continue by collecting data from the supermarket when is in operation to evaluate its performance and compare to the results from the design phase. The cooling demand of the medium temperature level is estimated between 100-140 kW depended on the ambient conditions and around 40 kW for the freezers. The COP in the medium temperature level is expected to be up to 7.8 and 2.5 for the low temperature level. The space heating COP is expected to be up to 7.3. QC 20210710 Building state-of-the-art (SotA) supermarket: Putting theory into practice

The energy outlook of a supermarket in Stockholm, as well as its refrigeration cycle efficiency are investigated based on field measurements. The refrigeration unit of the system is a CO2 trans-critical booster system with heat recovery, air conditioning, and geothermal storage integration. Field data are analyzed from 1st of January 2019 until the end of the same year. Based on the field measurements, low, medium temperature level, air conditioning cooling and space heating demands, as well as COP’s are calculated, for thirty-minute intervals, averaged to different ambient temperatures. The same method is used for calculating the thermal loads from the ground. The results show energy efficiency improvement comparing to previous studies, which originates from several factors such as: changes in the system design (e.g. three stage expansion), higher total efficiency of compressors, zero or low internal superheat at the three evaporation temperature levels resulting in higher evaporation temperatures. The COP for the medium temperature level reaches 8,5 and 7,5 for space heating. QC 20210710 Building state-of-the-art (SotA) supermarket: Putting theory into practice

This paper investigates the energy efficiency of geothermal storage integration into the state-of-the-art CO2 trans-critical booster systems. Three scenarios of integration are studied including stand-alone and integrated supermarket building systems. The results show that for a stand-alone supermarket, heat recovery from the CO2 system should be prioritized over extracting heat from the ground, which this heat extraction can be done either by an extra evaporator in the CO2 system or by a separate ground source heat pump. In the case of supermarket integration with a nearby district heating consumer, geothermal storage integration with extra evaporator in the CO2 refrigeration system can reduce the total annual running cost of the two buildings by 19-31% and with a payback time of less than three years. This integration is beneficial if the full efficient heat recovery capacity of the CO2 system is not sufficient to provide the entire demands. QC 20190909

Energy use is one of the main indicators for the economic and social development of a country, reflecting directly in the quality of life of the population. The expansion of energy use together with the depletion of fossil resources and the poor efficiency of energy systems have led many countries in recent years to invest in renewable energy sources. In this context, solar-assisted heat pump has become very important in energy industry, since it can transfer heat energy from the sun to water or another absorbing source. The direct-expansion solar assisted heat pump (DX-SAHP) water heater system operates by receiving solar energy incident in a solar collector, which serves as an evaporator in a refrigeration cycle, and the energy reject by the condenser is used for water heating. In this paper, a DX-SAHP using carbon dioxide as refrigerant (R744) was assembled, and the influence of the variation of the water mass flow rate in the system was analyzed. The parameters such as high pressure, water outlet temperature, gas cooler outlet temperature, evaporator temperature, and the coefficient of performance were studied. The mainly components used to assemble the heat pump were a reciprocating compressor, a gas cooler which is a countercurrent concentric tube heat exchanger, a needle-valve, and an evaporator that is a copper bare flat plate solar collector designed to capture direct and diffuse radiation. Routines were developed in the LabVIEW and CoolProp through MATLAB software’s, respectively, to collect data and calculate the thermodynamics properties. The range of coefficient of performance measured was from 3.2 to 5.34. It was noticed that, with the higher water mass flow rate, the water outlet temperature decreased, and consequently, the coefficient of performance of the system increases since the heat transfer in the gas cooler is higher. In addition, the high pressure of the system and the CO2 gas cooler outlet temperature decreased. The heat pump using carbon dioxide as a refrigerant, especially operating with solar radiation has been proven to be a renewable source in an efficient system for heating residential water compared to electrical heaters reaching temperatures between 40 °C and 80 °C., {"references":["Hepbasli, A.; Kalinci, Y. A review of heat pump water heating systems. Renewable and Sustainable Energy Reviews, n.12, p.1211-1229, 2009.","NEEA, Heat Pump Water Heater Model Validation Study, in, Northwest Energy Efficiency Alliance, p. 74-75, 2015.","Willem, H.; Lin, Y.; Lekov, A. Review of Energy Efficiency and System Performance of Residential Heat Pump Water Heaters, Energy and Buildings, v.143, p.191-201, 2017","Kong, X. Q.; Li, Y.; Lin, L. e Yang, Y. G. Modeling evaluation of a direct-expansion solar-assisted heat pump water heater using R410A. International Journal of Refrigeration, v. 76, p. 136-146, 2017.","Omojaro, P.; Breitkopf, C. Direct Expansion solar assisted heat pumps: A review of applications and recent research. Renewable and Sustainable Energy Reviews, v.22, p.33-45, 2013.","Kuang, Y. H., Sumathy, K., Wang, R.Z. Study on a direct-expansion solar-assisted heat pump water heating system. International Journal of Energy Research, v. 27, p. 531-548, 2003.","Chow, T. T.; Pei, G.; Fong, K. F.; Lin, Z.; Chan, A. L. S. e He, M. Modeling and application of direct-expansion solar-assisted heat pump for water heating in subtropical Hong Kong. Applied Energy, v.87, p. 643-649, 2010.","Kong, X. Q. Zhang, D.; Li. Y.; Yang, Q. M. Thermal performance an analysis of a direct- expansion solar- assisted heat pump water heater. Energy, v.36, n.12, p. 6830-6838, 2011.","Mota-Babiloni, A.; Makhnatch, P.; Khodabanceh, R. Recent investigations in HFCs substitution with lower GWP synthetic alternatives: focus on energetic performance and environmental impact. International Journal of Refrigeration, v.82, p.288-301, 2017. \n[10]\tAustin, B. T.; Sumathy, K. Transcritical carbon dioxide heat pump systems: A review. Renewable and Sustainable Energy Reviews, v.15, p.4013-4029, 2011.\n[11]\tMa, Y., Liu, Z., Tian, H. A review of transcritical carbon dioxide heat pump and refrigeration cycles. Energy, v.55, 156–172, 2013.\n[12]\tNeksá, Petter. CO2 heat pump systems. International Journal of Refrigeration, v. 25, p. 421-427, 2002. \n[13]\tSarkar, J.; Bhattacharyya, S.; Ramgopal, M. Performance of a transcritical CO2 heat pump for simultaneous water cooling and heating. International Journal of Engineering and Applied Sciences, v.16, p. 57-63, 2010.\n[14]\tSarkar, J.; Bhattacharyya, S. Operating characteristics of transcritical CO2 heat pump for simultaneous water cooling and heating. Archives of thermodynamics, n.4, v.33, p.23-40, 2012. \n[15]\tYokoyama, R.; Wakaui, T.; Kamakari, J.; Takemura, K.; Performance analysis of a CO2 heat pump water heating system under a daily change in a standardized demand. Energy, v. 35, p. 718-728, 2010. \n[16]\tMinetto, Sìlvia. Theorical and experimental analysis of a CO2 heat pump for domestic hot water. International Journal of Refrigeration, v. 34, p.742-751, 2011.\n[17]\tCecchinato, L.; Corradi, M.; Minetto, S. A critical approach to the determination of optimal heat rejection pressure in transcritical systems. Applied Thermal Engineering, v.30, p.1812-1823, 2010. \n[18]\tCecchinato, L.; Corradi, M.; Minetto, S. A simplified method to evaluate the energy performance of CO2 heat pump units. International Journal of Thermal Sciences, v.50, p.2483-2495, 2011. \n[19]\tCecchinato, L.; Corradi, M.; Minetto, S.; Stringari. P.; Zilio. C, Thermodynamic analysis of different two-stage transcritical carbon dioxide cycles. International Journal of Refrigeration, v.32, p. 1058-1067, 2009.\n[20]\tYamaguchi, S.; Kato, D.; Saito, K.; Kawai, S. Development and validation of static simulation model for CO2 heat pump. International Journal of Heat and Mass Transfer, v. 54, p. 1896-1906, 2011.\n[21]\tXu, X. X.; Chen, G. M.; Tang, L. M.; Zhu, Z. J. Experimental investigation on performance of transcritical CO2 heat pump system with ejector under optimum high-side pressure. Energy, v.44, p-870-877, 2012. \n[22]\tLin, K.; Kuo, C.; Hsieh, W.; Wang, C. Modeling and simulation of the transcritical CO2 heat pump system. International Journal of Refrigeration, v.36, p.2048-20654, 2013.\n[23]\tPurohit, N.; Gupta, D. K.; Dasgupta, M. S. Thermodynamic Analysis of Trans-Critical CO2 refrigeration Cycle in Indian Context. International Journal of Scientific and Technical Advancements, v.1. p.143-146, 2015. \n[24]\tRawat, K. S.; Bisht, V. S.; Pratibar, A. K. Thermodynamic Analysis and Optimization CO2 based Trasncritical Cycle. International Journal for Research in Applies Science and Engineering Technology, v. 3, p. 287-293, 2015.\n[25]\tOliveira, R. N.; Faria, R. N.; Antonanzas-Torres. F.; Machado. L.; Koury. R. N. N. Dynamic model and experimental validation for gas cooler of CO2 heat pump for heating residential water. Science and Technology for Built Environment, v.1, p.1-11, 2015. \n[26]\tFaria, R. N.; Nunes, R. O.; Koury, R. N. N.; Machado. L. Dynamic modeling study for a solar evaporator with expansion valve assembly of transcritical heat pump. International Journal of Refrigeration, 2016. DOI: 2016.01.004. \n[27]\tDuffie, J. A. e Beckman, W. A. Solar engineering of thermal processes. 4th edition, Hoboken: John Wiley and Sons, 2013.\n[28]\tBipm, I. E. A. evaluation of Measurement Data—Guide to the Expression of Uncertainty in Measurement GUM 1995 with minor corrections. Joint Committee for Guides in Metrology, JCGM, 2008.\n[29]\tWang, S.; Tuo, H.; Xing, Z. Experimental investigation on air-source transcritical CO2 heat pump water heater system at a fixed water inlet temperature. International Journal of Refrigeration, v.36, p.701-716, 2013."]}

The aim of this paper is to study the benefits of integrating CO2 trans-critical booster refrigeration system with geothermal storage. The ground is used as a heat sink for sub-cooling during the summer period and as a heat source for extracting heat in the winter season. Using field measurements from medium size supermarkets in Sweden, proposed and the existing system solutions for integrating geothermal storage in CO2 refrigeration systems are modelled and compared with standard CO2 trans-critical booster system. The techno-economical comparative analysis shows that hybrid CO2 trans-critical booster system with ground source heat pump (GSHP) as an integrated geothermal solution has 6% lower annual energy use compared to a stand-alone CO2 system with heat recovery. QC 20181105

This paper investigates the state-of-the art features of CO2 trans-critical booster systems. The performance of various modified features have been compared to the standard CO2 booster system. Subsequently, the performance of the defined state-of-the-art CO2 system is compared to natural refrigerant-based cascade, HFC/HFO-based DX and indirect refrigeration solutions, and propane water-cooled plug-ins operating in cold and warm climates. The results indicate that flooded evaporation and parallel compression are the most promising features of the state-of-the-art CO2 system. This compact and environmentally friendly system is the most energy efficient solution in cold climates, and is also an efficient solution in warm climates, with comparable efficiency to cascade and HFC/HFO DX systems, but with no existing or potential limitations. QC 20180821

Refrigeration Science and Technology, 13th IIR Gustav Lorentzen Conference on Natural Refrigerants (GL2018). Proceedings

Using heat pump technology to provide Space Heating (SH) and to produce Domestic Hot Water (DHW) for residential buildings has been widely applied during past decades. In this study, two scenarios adopting large-capacity propane heat pumps are defined and evaluated. These two scenarios, which are named after Scenario A and Scenario B respectively, provide SH and DHW either separately by two units or integrally by one unit. The COP1s of two scenarios are compared based on the simulation results from experimentally validated models. The results show that two scenarios have almost equal efficiency; the relative difference is within 6%. In the optimization analysis of Scenario B, varying DHW heating capacity produced by the desuperheater in the heat pump is modelled. The DHW demand ratio varies from approximately 9% to 20% with no detectable influences on the COP1. The corresponding COP1s and temperature profiles in the heat exchangers are demonstrated. The simulation results indicate that increasing DHW capacity in Scenario B can narrow down the temperature approach in the condenser and insignificantly improves the overall COP1s. QC 20181019

This paper reviews the guidelines of how to instrument, measure, monitor and evaluate refrigeration systems in supermarkets. The guidelines principles are firstly illustrated for a simple, single stage, refrigeration system: measurements requirements are analysed and the methodology to estimate refrigeration quantities are defined. Estimation for refrigerant mass flow rate and compressor power are more extensively described and their application on real field measurement data presented and discussed. The extension of the guidelines for a more complex refrigeration system is finally presented with focus on centralized systems providing cooling a multiple temperature levels: a HFC system with LT subcooler and a simple CO2 booster system. QC 20180725