Cycle Parameters Research Articles

Thermal performance enhancement of novel integrated vapor compression and organic rankine cycle for electricity production: a full-condensing vs. desuperheating approach comparison in ultra-low-grade waste heat recovery

This paper presents the thermodynamic analysis, performance assessment and working fluid selection for a novel integrated vapor compression cycle and the organic Rankine cycle system, which recovers ultra-low-temperature waste heat (50 °C) rejected by the condenser of a vapor compression cycle (VCC). The study is conducted on a vapor compression system of a 35 kW cooling capacity, followed by the component sizing of the organic Rankine cycle (ORC) based on the available waste heat in the condenser of the refrigeration system. The effect of the operational parameters of the vapor compression cycle on the overall system performance are investigated. The system performance of the integrated system is estimated in terms of coefficient of performance, cycle thermal efficiency and exergy efficiency. The novel integrated systems has been analyzed thermodynamically for 36 pairs of pure refrigerants. Results show that the working fluid pair R600a/R141b with combined coefficient of performance (3.54), ORC thermal efficiency (3.05 %), electricity saving ratio (13.34 %) and total exergy destruction (6.94 kW) is the most suitable VCC/ORC working fluid pair in full condensing method. R407c-R141b is found to be the best working fluid pair in desuperheating method for the same integrated system. The performance analysis for full condensation and desuperheating methods are also investigated. The results indicate a 12.5 % improvement in the coefficient of performance of the integrated system using the full condensation method and a 2.5 % improvement using the desuperheating method compared to the standalone air conditioning system. Additionally, the sensitivity analysis results show that there exists optimum operating condition that maximize the system performance of the integrated system.

Research on multi-objective parameter optimization of split flow dual flash thermodynamic cycle

In addition to considering the intermediate pressure variables, the split flow double flash thermodynamic cycle also needs to consider the operating conditions and split flow coefficient of the cycle. Traditional algorithms require too much computation and have a longer response time. Faced with sudden operating conditions or changes in production conditions, it is difficult to quickly re-optimize the intermediate parameters of the split flow double flash thermal cycle and carry out corresponding system control. This article uses intelligent optimization algorithms instead of global search methods to optimize multi-objective parameters in a split flow double flash thermodynamic cycle. By summarizing and analyzing the characteristics of algorithms such as SIO, EA, and ANN, it is believed that the GWO algorithm in the SIO class is the most suitable for multi-objective parameter optimization of the split flow double flash thermal cycle. It is combined with the SA optimization algorithm to propose the SA-GWO algorithm with faster optimization speed and higher optimization accuracy, taking the initial position of the wolf pack as the optimization objective. Combined with the cycle thermodynamic model, a multi-objective parameter optimization model for the split flow double flash thermal cycle is established.

Investigation of duty cycles for measuring activity in passive acoustic bat monitoring

Echolocating bats are important bioindicators that can be monitored effectively using passive acoustic monitoring (PAM) techniques. In PAM, duty-cycle-based temporal subsampling is often used to collect data at ON/OFF intervals to circumvent the limitations of recorder battery and storage capacity to enable long-term monitoring. However, potential bias introduced by temporal subsampling has not been systematically investigated for bat monitoring. Here, we use continuous audio recordings from the Union Bay Natural Area in Seattle in Summer 2022 to simulate the effects of temporal subsampling using different duty cycle parameters. We detected bat calls automatically using a deep learning model [Aodha et al., 2022, BioRxiv] and calculated three metrics as proxy for bat activity: number of calls, Activity Index (AI), and Bout Time Percentage (BTP). We found that although the number of calls and AI are more readily computable using the detected calls, BTP is likely a more accurate measure that relies less on the performance of automated call detection methods. In addition, reduced sampling for only a portion of the night (e.g., 4 hrs) was generally inadequate for capturing bat activity. Our results suggest that considering species-specific acoustic characteristics is crucial for reducing sampling bias for PAM of bats.

STATISTICAL ANALYSIS OF ABNORMAL UTERINE BLEEDING AMONG MALDIVIAN WOMEN OF REPRODUCTIVE AGE

Introduction. Abnormal uterine bleeding (AUB) describes uterine bleeding that varies from the usual parameters of a normal menstrual cycle [3]. AUB is one of the most common gynecologic problems among women of reproductive age. Approximately one-third of women experience AUB at some point in their lives [1]. Purpose of the study. This study aims to explore the prevalence and causes of AUB among Maldivian women of reproductive age who have experienced menstruation. Materials and method. An online questionnaire survey was conducted among reproductive-age Maldivians who have experienced menstruation. The study population was analyzed through exploratory data analysis. Research result. From the data collected, out of 110 participants, 37 (33.6%) individuals reported having irregular menses. Additionally, 22 (20%) individuals experienced menorrhagia. Moreover, 16 (14.5%) reported polymenorrhea, 14 (12.7%) reported amenorrhea and 9 (8.2%) reported oligomenorrhea. According to the data interpreted from the menstrual pictogram, it was observed that among the 35 participants self-reporting heavy menstrual bleeding, merely 20% (7 individuals) actually had a menstrual blood loss (MBL) exceeding 80ml. The average blood loss among these individuals was calculated to be 113 ml, highlighting a notable disparity between subjective perception and objective data. Out of the 68 individuals who reported a normal flow, 4 had a MBL exceeding 80ml, with a mean of 116.19 ml. Moreover, among the entire study group, 44 (40%) participants reported having a diagnosis of polycystic ovarian syndrome (PCOS), and 18 (16.4%) individuals reported having ovarian cysts. Furthermore, 2 (1.8%) individuals reported endometriosis, 2 (1.8%) individuals reported having uterine fibroids and, 2 (1.8%) individuals mentioned having cervical polyp, and 1 (0.9%) had an endometrial polyp. Conclusion. Using FIGO system 1 as a gateway to FIGO system 2 simplifies the process of investigating AUB [2]. Based on the criteria set by FIGO system 1, only 46 (41.8%) out of the 110 participants in the study were found to have a normal menstrual cycle. The remaining 64 (58.2%) participants experienced AUB. Out of these 64 (58.2%) participants, a total of 29 individuals have a diagnosis of PCOS. These findings suggest a significant association between AUB and PCOS within the study population.

A Theoretical Study on the Thermal Performance of an Increasing Pressure Endothermic Cycle for Geothermal Power Generation

In this study, a power cycle (IPEC), with an increasing pressure endothermic process in a downhole heat exchanger (DHE) and a CO2-based working fluid mixture, was developed for geothermal power generation. The increasing pressure endothermic process, which cannot be achieved in a conventional evaporator on the ground, was realized using the gravitational potential energy in the DHE. The parameters of the power cycle and the structural size of the DHE were optimized simultaneously. Using CO2-R32 as the working fluid of the IPEC provides the highest net power output. The net power generated with the IPEC was compared with a single-flash (SF) system, a trans-critical CO2 (t-CO2) system, and an organic Rankine cycle (ORC) under the same heat source and sink conditions. Six selection maps were generated for choosing the optimum power cycle for electricity production, in which four power generation systems (ORC, t-CO2, IPEC, and SF) were included, and two DHE diameters (0.155 m and 0.22 m) were investigated. It was found that the IPEC system had more net power output than the other three systems (ORC, t-CO2, and SF) under the conditions that the geofluid’s mass flow rate was less than 10 kg/s and its temperature was lower than 180 °C.

Trichoderma atroviride Enhances Impatiens walleriana Hook. f Growth and Flowering in Different Growing Media.

Trichoderma spp. are widely reported to regulate plant growth by improving nutrient uptake, photosynthesis, and abiotic stress tolerance. However, their possible application for bedding plants is little explored, especially when comparing different growing media. Considering that coconut coir dust is finding broader application in the ornamental plants sector as a peat substitute, this work was aimed to test the combination of Trichoderma atroviride AT10 and coconut coir dust on Impatiens walleriana plants. Four treatments were tested as a mix of: (i) two growing media (70:30), peat:perlite or coconut coir dust:perlite; and (ii) the absence or presence of a T. atroviride treatment. At the end of the production cycle, the biomass and ornamental parameters, leaf pigments, nutrient content of the plant tissues, and Trichoderma abundance were assessed. The results revealed that T. atroviride can readily colonize coir, and the same positive effects of inoculum were found in plants grown on both substrates. The biostimulant effect of T. atroviride was observed as an increase in the aboveground biomass, number and weight of flowers, pigments and nutrient concentration, thereby improving the commercial quality of I. walleriana. Thus, T. atroviride has shown its potential in making bedding plant cultivation more sustainable and improving the yield and aesthetic parameters of plants grown on peat and coconut coir dust substrates.

H2-sCO2 direct-fired power system coupled with electrolysis and storage

To maintain a global zero-emission policy and a high standard of living, new energy systems with higher system efficiency and net zero-emission productions need to be designed and deployed. This paper describes a novel integrated system between a direct-fired supercritical carbon dioxide (sCO2) power system with hydrogen and oxygen for zero-emission power generation and storage. sCO2 power cycles offer higher thermodynamic efficiencies than conventional gas-fired Brayton cycles. Heat is added to the system from the combustion of hydrogen and oxygen. The system consists of an electrolyzer unit and two cryogenic storage systems for hydrogen and oxygen. The proposed system is designed as a medium/long-term battery that can use excess electricity from the grid to produce hydrogen (electrolyzer) and supply to the grid (hydrogen combustion) in times of higher demand. Nitrous oxide emissions are mitigated by oxy-combustion and water separation from the post-combustion products allows for a closed-loop water cycle. The optimization of cycle parameters suggests a turbine inlet temperature of 1473 K and a pressure of 30 MPa for a specific net power output of 348 kJ/kg electrical. This results in an H2-sCO2 direct-fired power cycle efficiency of around 53 % with an overall system round-trip efficiency of up to 35 %.

Targeting the NF-κB p65/Bcl-2 signaling pathway in hepatic cellular carcinoma using radiation assisted synthesis of zinc nanoparticles coated with naturally isolated gallic acid

PurposeOral diethylnitrosamine (DEN) is a known hepatocarcinogen that damages the liver and causes cancer. DEN damages the liver through reactive oxygen species-mediated inflammation and biological process regulation. Materials and methodsGallic acid-coated zinc oxide nanoparticles (Zn-GANPs) were made from zinc oxide (ZnO) synthesized by irradiation dose of 50 kGy utilizing a Co-60 γ-ray source chamber with a dose rate of 0.83 kGy/h and gallic acid from pomegranate peel. UV–visible (UV) spectrophotometry verified Zn-GANP synthesis. TEM, DLS, and FTIR were utilized to investigate ZnO-NPs' characteristics.Rats were orally exposed to DEN for 8 weeks at 20 mg/kg five times per week, followed by intraperitoneal injection of Zn-GANPs at 20 mg/kg for 5 weeks. Using oxidative stress, anti-inflammatory, liver function, histologic, apoptotic, and cell cycle parameters for evaluating Zn-GANPs treatment. ResultsDEN exposure elevated inflammatory markers (AFP and NF-κB p65), transaminases (AST, ALT), γ-GT, globulin, and total bilirubin, with reduced protein and albumin levels. It also increased MDA levels, oxidative liver cell damage, and Bcl-2, while decreasing caspase-3 and antioxidants like GSH, and CAT. Zn-GANPs significantly mitigated these effects and lowered lipid peroxidation, AST, ALT, and γ-GT levels, significantly increased CAT and GSH levels (p<0.05). Zn-GANPs caused S and G2/M cell cycle arrest and G0/G1 apoptosis. These results were associated with higher caspase-3 levels and lower Bcl-2 and TGF-β1 levels. Zn-GANPs enhance and restore the histology and ultrastructure of the liver in DEN-induced rats. ConclusionThe data imply that Zn-GANPs may prevent and treat DEN-induced liver damage and carcinogenesis.

Optimization of Combustion Cycle Energy Efficiency and Exhaust Gas Emissions of Marine Dual-Fuel Engine by Intensifying Ammonia Injection

The capability of operational marine diesel engines to adapt to renewable and low-carbon fuels is considered one of the most influential methods for decarbonizing maritime transport. In the medium and long term, ammonia is positively valued among renewable and low-carbon fuels in the marine transport sector because its chemical elemental composition does not contain carbon atoms which lead to the formation of CO2 emissions during fuel combustion in the cylinder. However, there are number of problematic aspects to using ammonia in diesel engines (DE): in-tensive formation of GHG component N2O; formation of toxic NOx emissions; and unburnt toxic NH3 slip to the exhaust system. The aim of this research was to evaluate the changes in combustion cycle parameters and exhaust gas emissions of a medium-speed Wartsila 6L46 marine diesel engine operating with ammonia, while optimizing ammonia injection intensity within the limits of Pmax, Tmax, and minimal engine structural changes. The high-pressure dual-fuel (HPDF) injection strategy for the D5/A95 dual-fuel ratio (5% diesel and 95% ammonia by energy value) was investigated within the liquid ammonia injection pressure range of 500 to 2000 bar at the identified optimal injection phases (A −10° CAD and D −3° CAD TDC). Increasing ammonia injection pressure from 500 bar (corresponding to diesel injection pressure) in the range of 800–2000 bar determines the single-phase heat release characteristic (HRC). Combustion duration decreases from 90° crank angle degrees (CAD) at D100 to 20–30° CAD, while indicative thermal efficiency (ITE) increases by ~4.6%. The physical cyclic deNOx process of NOx reduction was identified, and its efficiency was evaluated in relation to ammonia injection pressure by relating the dynamics of NOx formation to local combustion temperature field structure. The optimal ammonia injection pressure was found to be 1000 bar, based on combustion cycle parameters (ITE, Pmax, and Tmax) and exhaust gas emissions (NOx, NH3, and GHG). GHG emissions in a CO2 equivalent were reduced by 24% when ammonia injection pressure was increased from 500 bar to 1000 bar. For comparison, GHG emissions were also reduced by 45%, compared to the diesel combustion cycle.

Double‐input triple‐output non‐isolated DC–DC converter based on coupled inductor with high step‐up output voltages

SummaryThis paper introduces a new non‐isolated double‐input triple‐output (DITO) high voltage gain DC–DC converter with a wide range of applications, including hybrid voltage source systems, solar home appliances, DC‐bus power distribution systems, and electrical vehicles (EVs). The proposed DITO converter interfaces two hybrid voltage sources to supply three different output loads with varying voltage and power levels. Compared to conventional converters of the same type, the proposed DITO converter offers several advantages, including operation for all duty cycles, integration of hybrid energy sources to transfer power to multiple loads, high voltage conversion ratio for all three‐output ports, a higher ratio of total voltage gain to total components number, common grounded input and output DC ports, simultaneous DC voltage regulation of three‐output ports by tuning separate controlling parameters of duty cycles, an additional turns ratio of coupled inductors to increase the voltage gain of output ports, and medium voltage stress on switches. The proposed DITO converter utilizes a new single‐switch single‐coupled‐inductor DC–DC structure, which is analyzed and verified through a prototype implementation for 25 and 30 V input voltages and 210, 330, and 400 V output voltages with a total power of 480 W. The experimental results confirm the simulation results and theoretical analysis.

Non-parametric fractional-order controller design for stable process based on modified relay

The relay feedback approach is an effective approach for real-time process control. However, it requires accurate limit cycle data. This paper proposes a novel relay feedback approach for fractional-order (FO) controller design to regulate the stable process performance. The proposed methodology does not require prior knowledge of the process and assures accurate limit cycle. Accurate limit cycle parameters are first estimated using the proposed relay. Then, the FO controller is designed based on the output of the limit cycle obtained through the proposed relay, phase, and Nyquist stability criteria. Further, the accuracy of the proposed relay is verified analytically through harmonic analysis. Various performance parameters and indices are estimated and compared with recently published techniques to assess the effectiveness. Additionally, disturbance and parametric uncertainty analyses are conducted to examine the disturbance rejection capacity and robustness. The efficacy of the proposed methodology is further validated on a real-time liquid-level control four-tank process.

Association of Serum progesterone level, Peak Expiratory Flow Rate and obesity in healthy young women.

Obesity is one of the lifestyle disorders which is slowly and steadily extending throughout the world. Women especially are showing an upward shift in Body mass index (BMI) in this modern era. Obesity in females has been associated with various risk factors. Less studies have been explored on the influence of BMI on different parameters of menstrual cycle The purpose of the study was to determine the influence of BMI on different parameters of the menstrual cycle. A total of 50 healthy female volunteers with regular menstrual cycle were selected after prior consent, and among them based on the body mass index, 32 females were categorized into obese group based on the BMI. Menstrual cycle history was monitored for 3 months for confirming regularity. Serum Progesterone and Peak expiratory flow rate (PEFR) were recorded. Progesterone levels were very highly significant in the luteal phase when compared to early follicular and ovulatory phase. The PEFR value in luteal phase was higher when compared to early follicular and ovulatory phase which was statistically highly significant. Positive correlation between progesterone and PEFR was observed in the luteal phase, but it was not statistically significant. Positive correlation between BMI and PEFR was also observed. The study reveals significant hormonal and respiratory changes throughout the menstrual cycle. Progesterone levels and PEFR are markedly higher in the luteal phase, while BMI positively correlates with PEFR. A significant negative correlation exists between Waist Hip ratio (WHR) in the luteal phase. Further studies are needed to explore the underlying mechanisms driving the correlations between progesterone, respiratory parameters, BMI, and WHR in more diverse population.

Neutronic Analysis and Fuel Cycle Parameters of Transuranic-UO2 Fueled Dual Cooled VVER-1000 Assembly

Abstract The feasibility of transuranic (TRU) fuel rods has been studied for a dual-cooled VVER-1000 assembly along with the conventional UO2 fuel rods. It has been found that the heterogeneous arrangements of TRU and UO2 fuel rods help to improve the multiplication factor, enhance the fuel cycle parameters, and maintain the negative Doppler coefficient of the reference VVER-1000 assembly. Within the different heterogeneous combinations of TRU and UO2 fuel rods, the equal number of UO2 and TRU fuel rods, which is referred to as model 6 increased the multiplication factor of the reference assembly by 7.66% at the beginning of the cycle. Furthermore, the fuel cycle parameter becomes almost double for this model in comparison with the reference assembly. TRU rods make the neutron spectrum of reference assembly slightly harder and increase the fast fission rate. However, the Doppler coefficient becomes less negative, and flux level decreases with increasing the number of TRU rods. By considering the safety parameters and neutronic behavior, model 6 (equal number of UO2 and TRU fuel rods) is to be effective for the annular fueled VVER-1000 reactor.

Towards sustainable process heating at 250 °C: Modeling and optimization of an R1336mzz(Z) transcritical High-Temperature heat pump

Fossil fuel boilers typically produce high-temperature process heating due to the impossibility of current renewable technologies. Vapour compression heat pump systems have been proposed up to 200 °C with subcritical cycles. To increase the heating production level, this paper proposes heating up to 250 °C through a transcritical high-temperature heat pump (THTHP) using R1336mzz(Z), which is not thermally degraded till this temperature, according to existing data. Computational models of a transcritical vapor compression cycle with and without an internal heat exchanger are developed for this work. The input cycle parameters, such as evaporation, production temperature, gas cooler output temperature, and the superheating degree, have been modified through iteration to consider possible scenarios in different industrial sectors. Moreover, the impact of using waste heat to increase evaporation temperature or superheating degree has been studied to optimize the cycle. The internal heat exchanger has also been considered for superheating the compressor suction. Other relevant parameters, such as compression ratio or volumetric mass flow rate, have also been assessed. The results show that a heat pump is feasible to reach 250 °C temperature using waste heat at 120 °C (evaporation at 100 °C and 20 °C of superheating degree), reaching a COP of 3.3. The variation of evaporator temperature from 80 °C to 140 °C increases COP from 2.5 to 5.9, while the increase of superheating degree from 20 °C to 100 °C increases COP from 3.2 to 7. Waste heat use optimization proves that it is more efficient to prioritize the increase of the evaporation temperature. If the industry requires lower production temperatures, the COP can reach a value of 7.0 at 180 °C. The decrease in gas cooler outlet temperature impacts less the COP than other input parameters. At baseline conditions, an optimum superheating degree with an internal heat exchanger of 45 K produces a maximum COP of 4.0. THTHP emissions are less than gas boilers for the same application, and in countries with greener electricity generation, these emissions can be 50 times lower.

Amplifying PCR productivity and environmental sustainability through shortened cycling protocols

Since its inception in the 1980s, advancements in PCR technology using improved thermal cyclers, engineered DNA polymerases and commercial master mixes, have led to increased PCR productivity. Despite these advancements, PCR cycling protocols have largely remained unchanged over the same period. This study aimed to systemically evaluate the effect of reduced PCR cycling parameters on amplicon production. The 1466bp fragment from the 16S rRNA gene present in low-, medium- and high-CG bacteria was amplified using three commercially available PCR master mixes. The shortest cycling parameters required to successfully amplify the 16S fragment from all bacteria and master mixes comprised 30-cycles of 5 s denaturation, 25 s annealing, and 25 s extension. While all produced an amplicon with sufficient yield to enable downstream sequence analysis, the PCRBIO Ultra Mix in conjunction with the shortened parameters was found to achieve the highest amplicon yield across low-, medium- and high CG bacteria. Comparing the run times to that of a typical 16S PCR protocol, the shortened cycling parameters reduced the program duration by 46 % and consumed 50 % less electricity, translating into increased productivity and helping to improve laboratory environmental sustainability.

Statistical Relations among Solid Precipitation, Atmospheric Moisture and Cloud Parameters in the Arctic

Observations collected during cold-season precipitation periods at Utquagvik, Alaska and at the multidisciplinary drifting observatory for the study of Arctic climate (MOSAiC) are used to statistically analyze the relations among the atmospheric water cycle parameters including the columnar supercooled liquid and ice amounts (expressed as liquid-water and ice-water paths, i.e., LWP and IWP), the integrated water vapor (IWV) and the near-surface snowfall rate. Data come from radar and radiometer-based retrievals and from optical precipitation sensors. While the correlation between snowfall rate and LWP is rather weak, correlation coefficients between radar-derived snowfall rate and IWP are high (~0.8), which is explained, in part, by the generally low LWP/IWP ratios during significant precipitation. Correlation coefficients between snowfall rate and IWV are moderate (~0.45). Correlations are generally weaker if snowfall is estimated by optical sensors, which is, in part, due to blowing snow. Correlation coefficients between near-surface temperature and snowfall rates are low (r &lt; 0.3). The results from the Alaska and MOSAiC sites are generally similar. These results are not very sensitive to the amount of time averaging (e.g., 15 min averaging versus daily averages). Observationally based relations among the water cycle parameters are informative about atmospheric moisture conversion processes and can be used for model evaluations.

The effect of harvesting the anterior half of the peroneus longus tendon on foot morphology and gait

Background and objectivesIn anterior cruciate ligament reconstruction, the strength of the graft was found to be unsatisfactory usually the anterior half of the peroneus longus tendon was taken for supplementation, but the effect on foot and ankle function and gait in the donor area is unclear. This study aims to explore the changes in the ankle and gait after using the harvested anterior half of the peroneus longus tendon as a reconstruction graft for the anterior cruciate ligament.MethodsA total of 20 patients, 6 males and 14 females, aged 18 to 44 years, with unilateral anterior cruciate ligament injuries, underwent reconstruction using the harvested anterior half of the peroneus longus tendon as a graft between June 2021 and December 2021. The part on which the anterior half of the peroneus longus tendon was harvested was considered the experimental group, while the contralateral foot was the control group. At the 6-month follow-up, the Lysholm knee score, AOFAS ankle score, and gait-related data (foot length, arch index, arch volume, arch volume index, and gait cycle parameters: percentage of time in each gait phase, step frequency, step length, foot strike angle, and push-off angle) were assessed using a 3D foot scanner and wearable sensors for both groups.ResultsAll 20 patients completed the six-month follow-up. There were no statistically significant differences between the experimental and control groups regarding knee scores, ankle scores, foot length, arch index, arch volume, arch volume index, step frequency, and step length (P > 0.05). However, there were statistically significant differences between the experimental and control groups in terms of the gait cycle parameters, including the percentage of time in the stance, mid-stance, and push-off phases, as well as foot strike angle and push-off angle (P < 0.05).ConclusionThrough our study of the surgical experimental group we have shown that harvesting the anterior half of the peroneus longus tendon does not affect foot morphology and gait parameters; however, it does impact the gait cycle.

Comparison of climate time series – Part 5: Multivariate annual cycles

Abstract. This paper develops a method for determining whether two vector time series originate from a common stochastic process. The stochastic process considered incorporates both serial correlations and multivariate annual cycles. Specifically, the process is modeled as a vector autoregressive model with periodic forcing, referred to as a VARX model (where X stands for exogenous variables). The hypothesis that two VARX models share the same parameters is tested using the likelihood ratio method. The resulting test can be further decomposed into a series of tests to assess whether disparities in the VARX models stem from differences in noise parameters, autoregressive parameters, or annual cycle parameters. A comprehensive procedure for compressing discrepancies between VARX models into a minimal number of components is developed based on discriminant analysis. Using this method, the realism of climate model simulations of monthly mean North Atlantic sea surface temperatures is assessed. As expected, different simulations from the same climate model cannot be distinguished stochastically. Similarly, observations from different periods cannot be distinguished. However, every climate model differs stochastically from observations. Furthermore, each climate model differs stochastically from every other model, except when they originate from the same center. In essence, each climate model possesses a distinct fingerprint that sets it apart stochastically from both observations and models developed by other research centers. The primary factor contributing to these differences is the difference in annual cycles. The difference in annual cycles is often dominated by a single component, which can be extracted and illustrated using discriminant analysis.

Influence of temperature combined with photodynamic inactivation on the development of Aedes aegypti

To reduce the speed of selection of populations resistant to chemical insecticides, photodynamic inactivation (PDI) against Aedes aegypti is a hot-topic and promising alternative technique to vector control. Temperature is an important factor in the survival of Ae. aegypti larvae and mosquitoes as it influences physiology, behavior, and ecology. This work aimed to evaluate parameters of the biological cycle of Ae. aegypti such as: hatching rate, larval development, adult mosquito longevity, sex ratio, weight, and lethal concentration of larval mortality (LC) through the combination of PDI with different temperatures. The number of larvae found after 48 h suggests that temperature affects hatching rate. Additionally, results showed a delay in development of surviving larvae after PDI when compared to control groups, and there was a reduction in the longevity of mosquitoes that undertook photodynamic action. PDI also led to a predominance of male insects, and observed weight indicates that the inactivation method may have also interfered in mosquito size. The results point to a satisfactory performance of PDI at all tested temperatures. Experimental conditions that were not lethal to all larvae implied that PDI impacts the mosquitoes’ biological cycle. Though metabolism and development are improved at higher temperatures, so is PDI action, thus maintaining the net benefit. Therefore, it is assumed that the proposed photolarvicide can be useful in reducing arbovirus transmission, and results invite for future research in different abiotic conditions.

Outcomes of BRCA pre-implantation genetic testing according to the parental mutation origin: a cohort study

BackgroundThe process of gamete formation and early embryonic development involves rapid DNA replication, chromosome segregation and cell division. These processes may be affected by mutations in the BRCA1/2 genes. The aim of this study was to evaluate BRCA mutation inheritance and its effect on early embryonic development according to the parental origin of the mutation. The study question was approached by analyzing in vitro fertilization cycles (IVF) that included pre-implantation testing (PGT-M) for a BRCA gene mutation.MethodsThis retrospective cohort study compared cycles of pre-implantation genetic testing for mutations (PGT-M) between male and female patients diagnosed with BRCA 1/2 mutations (cases), to a control group of two other mutations with dominant inheritance (myotonic dystrophy (MD) and polycystic kidney disease (PKD)). Results were compared according to mutation type and through a generalized linear model analysis.ResultsThe cohort included 88 PGT-M cycles (47 BRCA and 41 non-BRCA) among 50 patients. Maternal and paternal ages at oocyte retrieval were comparable between groups. When tested per cycle, FSH dose, maximum estradiol level, oocytes retrieved, number of zygotes, and number of embryos available for biopsy and affected embryos, were not significantly different among mutation types. All together 444 embryos were biopsied: the rate of affected embryos was comparable between groups. Among BRCA patients, the proportion of affected embryos was similar between maternal and paternal mutation origin (p = 0.24). In a generalized linear model analysis, the relative oocyte yield in maternal BRCA patients was significantly lower (0.7, as related to the non BRCA group)(p < 0.001). Zygote formation and blastulation were not affected by the BRCA gene among paternal cases (P = 0.176 and P = 0.293 respectively), nor by paternal versus maternal BRCA carriage (P = 0.904 and P = 0.149, respectively).ConclusionsBRCA PGT-M cycles performed similarly compared to non-BRCA cycles. Inheritance rate and cycle parameters were not affected by the parental origin of the mutation.