Mass Increment Research Articles

The Discovery of Accelerating Expansion of Universe 8.8 Billion Years after the Big Bang Vindicates M1 World One Out of the Six Solutions of Einstein’s General Theory of Relativity

This paper gives the mathematical methodology (Tensor mathematics) of describing the surfaces of our Universe in General Theory of Relativity. It expresses the mass energy equivalence formula. It introduces the concept of time dilation, length contraction and mass increment in high speed frame of reference. Minowski space time 4D manifold is illustrated for representing the flat spacetime fabric Reimannian Metric is enumerated. Schwarzschild metric and how mass is accounted for is given.

Optimizing Resistance Training for Sprint and Endurance Athletes: Balancing Positive and Negative Adaptations.

Resistance training (RT) triggers diverse morphological and physiological adaptations that are broadly considered beneficial for performance enhancement as well as injury risk reduction. Some athletes and coaches therefore engage in, or prescribe, substantial amounts of RT under the assumption that continued increments in maximal strength capacity and/or muscle mass will lead to improved sports performance. In contrast, others employ minimal or no RT under the assumption that RT may impair endurance or sprint performances. However, the morphological and physiological adaptations by which RT might impair physical performance, the likelihood of these being evoked, and the training program specifications that might promote such impairments, remain largely undefined. Here, we discuss how selected adaptations to RT may enhance or impair speed and endurance performances while also addressing the RT program variables under which these adaptations are likely to occur. Specifically, we argue that while some myofibrillar (muscle) hypertrophy can be beneficial for increasing maximum strength, substantial hypertrophy can lead to macro- and microscopic adaptations such as increases in body (or limb) mass and internal moment arms that might, under some conditions, impair both sprint and endurance performances. Further, we discuss how changes in muscle architecture, fiber typology, microscopic muscle structure, and intra- and intermuscular coordination with RT may maximize speed at the expense of endurance, or maximize strength at the expense of speed. The beneficial effect of RT for sprint and endurance sports can be further improved by considering the adaptive trade-offs and practical implications discussed in this review.

Optimal height distribution design and experimental validation of pin-fin heat sink under natural convection based on dynamic surrogate model

Pin-fin heat sinks are widely employed to dissipate heat from power devices under natural convection conditions. To improve heat dissipation performance, optimization of the fin height distribution was conducted in this study. In order to enhance optimization efficiency, we propose a dynamic surrogate model that integrates machine learning, iteratively sampling and training until the convergence criterion is met. Compared with traditional surrogate models, the dynamic surrogate model significantly reduces the prediction error of the optimal result, proving more efficient and yielding superior outcomes with fewer samples. By optimizing the fin height distribution, the heat sink thermal resistance was minimized without increasing mass. Subsequently, an experimental bench was developed to compare the heat sink's total thermal resistance pre- and post-optimization under natural convection conditions. Experimental results demonstrate that within the input heat flux range of q = 500–1200 W/m2, the optimized heat sink's total thermal resistance is diminished by 6.08% to 8.01%, without any mass increment, which confirms the dynamic surrogate model's efficacy in natural convection scenarios. This study elucidates the design principles governing the height distribution of pin-fins of heat sinks under natural convection, and provides a significant insight for guiding the design of pin-fin heat sinks.

System performance comparison of oxygen consumption and air separation for aircraft fuel tank inerting

To compare the performance of oxygen consumption and air separation inerting systems. This paper established the mathematical models of the oxygen consumption inerting system and air separation inerting system by mass conservation and energy conservation formula, and the equal inerting time method is adopted to assess the overall performance of the two systems. The two system performances, such as volume flow, thermal load, thermal power, mass increment, and additional fuel consumption, are compared. The results show that: The volume flow of the oxygen consumption inerting system is only 22.9% of the air separation system because of its internal circulation air injection characteristics. Furthermore, the thermal load of the oxygen consumption inerting system is reduced by 30% compared to the air separation system. The total additional fuel consumption of the oxygen consumption inerting system is reduced by 93.57% compared to the air separation system.

Tuber production of Tropaeolum pentaphyllum Lam. from different sizes of seed-tubers in two cultivation cycles

The liana Tropaeolum pentaphyllum Lam. is an unconventional food plant with potential economic exploitation. This study aimed to evaluate the vegetative propagation of T. pentaphyllum using seed-tubers. A total of 140 tubers were classified into four mass classes: I) < 10 g, II) 10 to 30 g, III) 30 to 70 g, and IV) > 70 g. Each mass class contained 35 tubers. The experiment was carried out in a greenhouse at Federal Institute of Rio Grande do Sul, Sertão, southern Brazil, with temperature and relative humidity of 25°C and 50%, respectively. When the senescence of the aerial stem system occurred, the mass of the tubers was measured using a precision scale (0.01 grams). Analysis of variance and Tukey’s test (p < 0.05) were used to analyze the data obtained in the experiment. In addition, descriptive statistics (mean ± standard deviation) were also used. The ratio between the initial and final masses per tuber class was calculated and the production averages between tuber classes were compared. The annual and biennial productions show that the classes of tuber seeds with mass above 10 g (II, III, and IV) produce more tubers. Class II and III are indicated for annual cultivation considering both the production in number and mass. Regarding the production of tubers for sale, class I with biennial planting is indicated since it presents a more significant mass increment.

Influence of biochar in the calcite precipitation of sandy soil using sporosarcina ureae

The microbially induced calcium carbonate precipitation (MICP) technology is an emerging novel and sustainable technique for soil stabilization and remediation. MICP, a microorganism-mediated biomineralization process, has attracted interest for its potential to enhance soil characteristics. The inclusion of biochar, a carbon-rich substance formed by biomass pyrolysis, adds another degree of intricacy to this process. The study highlights the impact of the combination of biochar and MICP together, using a bacterium, Sporosarcina ureae, on soil improvement. This blend of MICP and biochar improved the soil in terms of its geotechnical properties and also enabled the sequestering of carbon safely. It was observed that addition of 4% biochar significantly increased the soil's shear strength parameters (c and φ) as well as its stiffness after 21 treatment cycles. This improvement was because the calcium carbonate precipitate, which acts as a crucial binding agent, increased significantly due to microbial action in the soil-biochar mixture compared to the pure soil sample. The excess carbonate precipitation on account of biochar addition was verified through SEM-EDAX analysis where the images showed noteworthy carbonate precipitation on the surface of particles and increment in the calcium mass at the same treatment cycles when compared with untreated sand. The collaboration between MICP and biochar effectively increased the carbon sequestration within the sand sample. It was observed that at 21 cycles of treatment, the carbon storage within the sand sample increased by almost 3 times at 4% biochar compared to sand without any biochar. The statistical analysis further affirmed that strength depends on both biochar and the number of treatment cycles, whereas carbon sequestration potential is primarily influenced by the biochar content alone. This strategy, as a sustainable and environmentally friendly approach, has the potential to reform soil improvement practices and contribute to both soil strength enhancement and climate change mitigation, supporting the maintenance of ecological balance.

Body composition and associated factors among 5-7-year-old children with moderate acute malnutrition in Jimma town in southwest Ethiopia: A comparative cross-sectional study.

Acute malnutrition affects not only the growth and development but also the body composition of children. However, its specific effects have not yet been characterized. This study aims to compare the body composition of 5-7-year-old children with moderate acute malnutrition (MAM) to that of their well-nourished (WN) peers and identify associated factors. A school-based comparative cross-sectional study was conducted from June to July 2022 in Jimma town, southwest Ethiopia. The study participants were selected from eight kindergartens and eight primary schools using a simple random sampling technique based on the proportional allocation of the sample to the size of the population in the respective school. Descriptive statistics and multivariable linear regression analyses were used to assess the mean differences and associations between variables and isolate independent predictors of body composition, respectively. The statistical significance was determined using ß-coefficients with 95% confidence intervals and a p value of ≤ 0.05. Data were captured from 388 (194 MAM and 194 WN) children with a response rate of 97.9%. The mean fat-free mass of WN children was significantly higher compared with those with MAM (p < 0.001). The mean (SD) of fat mass of MAM children was 4.23 ± 0.72 kg, 4.36 ± 0.88 kg and 4.08 ± 0.89 kg for 5, 6 and 7-year-olds, respectively. For WN children, the mean (SD) of fat mass was 4.92 ± 0.88 kg for 5 years old, 5.64 ± 1.01 kg for 6 years old and 5.75 ± 1.26 kg for 7 years old (p < 0.001). On the multivariable linear regression analysis after controlling for background variables, WN children exhibited 1.51 times higher fat-free mass compared with MAM children (β = 1.51, p = 0.003). A unit increase in age of the study participants was associated with a 1.37 increment in fat-free mass (β = 1.37, p < 0.001). WN children had 1.07 times higher fat mass compared with children with MAM (β = 1.07, p < 0.001). A unit increase in the age of the child resulted in 0.15 times increment in fat mass (β = 0.15, p = 0.020), and being female was associated with a 0.37 increase in fat mass (β = 0.37, p < 0.001). The results showed that the mean fat mass and fat-free mass were significantly lower among moderately acute malnourished children than in WN children showing the loss of both body compartments due to malnutrition. The body mass index for age, age of the child and sex of the child were significantly linked to both fat-free mass and fat mass.

Patterns of integrated growth of body parts in Rook (Corvus frugilegus) ontogeny.

The early period of ontogeny is key to understanding the patterns of body plan formation in birds. Most studies of avian development have focused on the development of individual avian characters, leaving their developmental integration understudied. We explored the dynamics and integration of relative percentage increments in body mass, lengths of head, skeletal elements of wing and leg, and primary flight feathers in the embryonic and postnatal development of the Rook (Corvus frugilegus). The relative percentage increments were calculated according to Brody's equation. Groups of similar growing traits (modules) were determined using hierarchical cluster analysis, and the degree of correlation between modules was estimated by PLS analysis. The embryonic and postnatal periods demonstrate significant consistency both in the dynamics of changes in relative percentage increments of studied traits as well as in the clustering of individual modules. The modules mainly include the body mass and head length, as well as the elements that form the fore- and hind limbs. Differences were revealed in the combination of modules into clusters in embryonic and postnatal periods. Hind limb elements clustered together with wing elements in the embryonic period but with body mass and the head in the postnatal period. The strongest modularity was noted for the leg in embryogenesis, and for the wing in postnatal development. The forelimb and especially the primary feathers had more distinctive growth patterns. We suggest the changes in the degree of integration between locomotor modules in ontogenesis are connected with the earlier functioning of the legs in the postnatal period and with the preparation of the wings for functioning after a chick leaves the nest.

Strengthening non-engineered building using vegetal FRCM retrofitting: A numerical modeling approach for seismic assessment

The concept of developing alternative rehabilitation techniques to enhance the performance of structures with low seismic resistance has come to light in recent years. Substantial research and methods have been devoted to evolving strengthening techniques worldwide for structures with economic value, with the ultimate goal of enhancing seismic resilience in them. Among these, Fiber Reinforced Cementitious Matrix (FRCM) stands out as a reliable alternative to conventional retrofitting approaches due to its high strength-to-density ratio and negligible mass increment. However, the inadequacy of full-scale modeling and the application of FRCM in building components persist in the research domain. Therefore, this paper aims to develop a numerical model for the full-scale application of vegetal FRCM composites in retrofitting a representative non-engineered building. The full-scale application of the four vegetal FRCM materials (hemp, cotton, flax, and sisal) in 1-ply and 2-ply configurations was undertaken to strengthen a non-engineered building. The results of pushover analysis show that buildings retrofitted with 2-ply hemp and 2-ply flax FRCM exhibited the most significant improvement in base shear strength, with increments of about 30% and 28.5% respectively, compared to the peak base shear of the bare frame. Additionally, the retrofitted models demonstrated an increase in their ductility. A subsequent fragility analysis highlighted a reduction in the seismic hazard vulnerability of the building for the relevant earthquake spectrums. Finally, the results from the numerical analysis confirm that the use of vegetal fibers as cementitious matrix can have significant potential to be an effective and sustainable strengthening technique for seismically deficient buildings.

Python farming as a flexible and efficient form of agricultural food security

Diminishing natural resources and increasing climatic volatility are impacting agri-food systems, prompting the need for sustainable and resilient alternatives. Python farming is well established in Asia but has received little attention from mainstream agricultural scientists. We measured growth rates in two species of large pythons (Malayopython reticulatus and Python bivittatus) in farms in Thailand and Vietnam and conducted feeding experiments to examine production efficiencies. Pythons grew rapidly over a 12-month period, and females grew faster than males. Food intake and growth rates early in life were strong predictors of total lifetime growth, with daily mass increments ranging from 0.24 to 19.7 g/day for M. reticulatus and 0.24 to 42.6 g/day for P. bivittatus, depending on food intake. Pythons that fasted for up to 4.2 months lost an average of 0.004% of their body mass per day, and resumed rapid growth as soon as feeding recommenced. Mean food conversion rate for dressed carcasses was 4.1%, with useable products (dressed carcass, skin, fat, gall bladder) comprising 82% of the mass of live animals. In terms of food and protein conversion ratios, pythons outperform all mainstream agricultural species studied to date. The ability of fasting pythons to regulate metabolic processes and maintain body condition enhances food security in volatile environments, suggesting that python farming may offer a flexible and efficient response to global food insecurity.

Differentiation of isomeric chalcone and dihydroflavone using liquid chromatography coupled with hydrogen-deuterium exchange tandem mass spectrometry (HDX-MS/MS): An application for flavonoids-focused characterization of Snow chrysanthemum

Although the co-occurrences of isomeric chalcones and dihydroflavones widely appear in medicinal plants, the differentiation of such isomerism seldom succeeds using MS/MS, attributing to totally identical MS/MS spectra. Here, efforts were paid to pursue an eligible tool allowing to address the technical challenge. Being inspired by that one more proton signal is observed in 1H NMR spectrum of isoliquiritigenin than liquiritigenin when employing DMSO‑d6 as solvent, hydrogen-deuterium exchange (HDX)-MS/MS was evaluated towards differentiating isomeric chalcones and dihydroflavones through replacing H2O with D2O to prepare the mobile phase. As a result, differences were observed for either MS1 or MS2 spectrum when comparing two pairs of isomers, such as liquiritigenin vs. isoliquiritigenin and liquiritin vs. isoliquiritin, because the isomeric precursor and fragment ion species owned different amounts of hydroxyl protons and those reactive protons could be partially or completely substituted by deuterium protons at the exposure in D2O to result in n × 1.006 mass increments. Moreover, utmost four hydrogen/deuterium exchanges occurred for a single glucosyl moiety. Thereafter, HDX-MS/MS was applied to characterize the flavonoids of Snow chrysanthemum, a precious edible herbal medicine that is rich in isomeric chalcones and dihydroflavones. Through paying special attention to the deuterium labeling styles of (de)protonated molecules as well as those featured fragment ions, five pairs of isomeric chalcones and dihydroflavones were confirmatively differentiated, in addition to that 28 flavonoids were structurally annotated by applying those well-defined mass fragmentation rules. Hence, this study offered an in-depth insight towards the flavonoids-focused characterization of Snow chrysanthemum, and more importantly, HDX-MS/MS is a superior tool to differentiate, but not limited to, isomeric chalcones and dihydroflavones.

Meat productivity and quality of meat and liver of broiler chickens after consuming diet with mineral supplements containing chelates of cuprum, iron, zinc, and manganese

Poultry farming plays an important role as a producer of high-quality animal protein, which can solve issues of protein deficit among the population. Genetic growth potential of broiler chickens can be maximized through regular supply of microelements, especially chelate aminoacids. Those compounds improve metabolic processes in the body and increase increments in live mass and slaughter-yield of meat. The main objective of the study was identifying effects of mineral supplements with chelate microminerals on meat productivity of broiler chickens, quality of breast and thigh muscles, and content of mineral compounds in meat and liver. The studies were carried out on Kobb-500 broiler chickens, divided into three groups, each comprising 25 individuals. The experiment lasted from day 1 to day 42 of raising poultry. Broilers of the control group received the basic diet balanced in nutrients; the diet of birds of the second group was supplemented with Kronotsyd-L with chelates of copper, iron, zinc, and manganese in calculation of 0.25 mL/L of water, and chickens of the third consumed a diet with copper glycinate in calculation of 0.30 mL/L of water. Subject to mineral supplements with chelate microelements, the chickens had the highest mean-daily increments of live mass, slaughter yield, and yield of breast muscles. Use of mineral supplements in the diet of broiler chickens affected the quality of their meat, in particular its chemical composition. Those supplements led to changes in mineral composition of meat, influencing the concentrations of individual minerals in the tissues of the birds. Since minerals are important components of protein metabolism, the supplements augmented the content of dry matter and protein in meat. In the broiler chickens that had been receiving copper glycinate, the breast muscles had statistically significant increases in the mass shares of dry matter and protein. We found decrease in the content of fat in the breast and thigh muscles and the liver subject to copper glycinate and Kronotsyd-L with chelates of copper, iron, zinc, and manganese. This indicates improvement of the quality of meat and the liver. Use of mineral supplements with chelated microelements increased the ash content in dry matter because of higher concentrations of phosphorus, calcium, magnesium, iron, and manganese.

Conceptual Design of a Hydrogen-Hybrid Dual-Fuel Regional Aircraft Retrofit

A wide range of aircraft propulsion technologies is being investigated in current research to reduce the environmental impact of commercial aviation. As the implementation of purely hydrogen-powered aircraft may encounter various challenges on the airport and vehicle side, combined hydrogen and kerosene energy sources may act as an enabler for the first operations with liquid hydrogen propulsion technologies. The presented studies describe the conceptual design of such a dual-fuel regional aircraft featuring a retrofit derived from the D328eco under development by Deutsche Aircraft. By electrically assisting the sustainable aviation fuel (SAF) burning conventional turboprop engines with the power of high-temperature polymer-electrolyte fuel cells, the powertrain architecture enables a reduction of SAF consumption. All aircraft were modeled and investigated using the Bauhaus Luftfahrt Aircraft Design Environment. A description of this design platform and the incorporated methods to model the hydrogen-hybrid powertrain is given. Special emphasis was laid on the implications of the hydrogen and SAF dual-fuel system design to be able to assess the potential benefits and drawbacks of various configurations with the required level of detail. Retrofit assumptions were applied, particularly retaining the maximum takeoff mass while reducing payload to account for the propulsion system mass increase. A fuel cell power allocation of 20% led to a substantial 12.9% SAF consumption decrease. Nonetheless, this enhancement necessitated an 18.1% payload reduction, accompanied by a 34.5% increment in propulsion system mass. Various additional studies were performed to assess the influence of the power split. Under the given assumptions, the design of such a retrofit was deemed viable.

Hydrothermal synthesis of LDO/vinasse biochar composites with ultra-high specific surface areas for phosphate remediation and fertilizer utilization

In this work, CaMgAl-layered double oxide/biochar (LDO@BC) composites were elaborated by hydrothermal coprecipitation and calcination for the efficient recovery of phosphate as well as the further application of the reclaimed composites as fertilizers. On the one hand, the appropriate selection of biochar derived from vinasses as the substrates could solve the limitations of LDO like low specific surface areas as well as poor dispersion. The obtained composites possess the ultrahigh specific surface area as high as 508.97 m2/g. Therefore, a maximum adsorption capacity of 153.64 mg/g is achieved. In addition, our composites are with fast adsorption rates that nearly 100 % phosphate could be removed within 60 s at a trace concentration owing to the large specific surface areas. On the other hand, the recovered adsorbents could be used as fertilizers because of the high contents of P, Ca and Mg elements. The phosphate-adsorbed LDO@BC (P-LDO@BC) demonstrated a positive fertilization effect, significantly accelerating plant growth with length increment by 0.75 times and mass increment by 2.09 times compared with the control groups. Thus, this work not only provides a new approach for waste vinasse utilization, but also presents a promising adsorbing material for phosphate recovery and reuse.

Research on the Cumulative Damage Law of Surrounding Rock under Cyclic Blasting Action

In order to study the cumulative damage characteristics and laws of rock masses under cyclic blasting loads, based on the finite element software ANSYS/LS-dyna and the HJC constitutive model, a single blasting damage analysis is conducted first, and the accuracy of the results is verified. On this basis, numerical simulation studies on the cumulative damage of rock masses under cyclic blasting are carried out separately. The results indicate that the cumulative damage evolution cloud map of the rock mass under cyclic blasting is similar to that of a single blasting action, showing an inverse S-shape overall. The damage increment of the rock mass decreases with the increase of blasting times, and in the central area of the damage zone, the rock mass is particularly affected by the superimposed effect of cyclic blasting loads. Cyclic blasting fully reflects the accumulation of damage to the rock mass under multiple cyclic blasting loads, and there is a certain relationship between rock mass damage and the distance between the blasting centers. As the distance between the blasting centers increases, the amount and increment of rock mass damage generated by blasting continue to decrease.

Physical exercise and chicken egg white supplementation increase muscle mass of stable COPD patients.

Patients with chronic obstructive pulmonary disease (COPD) commonly exhibit muscle atrophy and dysfunction due to a reduction in muscle mass; and protein supplements such as chicken egg whites have been reported to improve muscle mass. The aim of this study was to evaluate the impact of physical exercise and egg white supplementation on the muscle mass of COPD patients. An experimental study was conducted among stable COPD patients at Universitas Sumatra Utara Hospital Medan, Indonesia, between August and October 2022. The patients were divided into two groups, control and interventional groups, with each patient subjected to a pre- and post-muscle mass assessment. All the patients performed respiratory endurance and upper extremity muscle strength training three times/week for a total of 12 weeks. In addition, the patients in the intervention group were also given egg white supplementation (10 eggs/day) during the period of intervention in addition to the physical training. The Wilcoxon and Mann-Whitney tests were performed to identify the significance of the difference between pre- and post-intervention and between the control and intervention groups, respectively. A total of 38 COPD patients were included in the study, 19 from each group. Our data suggested no significant difference in muscle mass of the patients in the control group before and after 12 weeks of physical exercise (pre-intervention 27.37±4.54% and post-intervention 27.68±4.5% with p=0.174). However, there was a significant muscle mass increment of patients in the intervention group upon 12 weeks of physical training and egg white supplementation (pre-intervention 27.18±4.15%, post-intervention 29.95±3.76%, p<0.001). A significant difference in muscle mass was observed between patients in the control and the intervention groups (p=0.046) after the intervention. The study highlights that physical exercise in combination with egg white supplementation may serve as potential and effective non-pharmacological treatment for muscle mass restoration in COPD patients as compared to physical exercise alone.

An assessment of ozone risk for date palm suggests that phytotoxic ozone dose nonlinearly affects carbon gain

Tropospheric ozone (O3) is a significant phytotoxic air pollutant that has a negative impact on plant carbon gain. Although date palm (Phoenix dactylifera L.) is a globally important crop in arid or semi-arid regions, so far O3 risk assessment for this species has not been reported. This study estimated leaf- and plant-level photosynthetic CO2 uptake for understanding how elevated levels of O3 affects date palm biomass growth. Ozone risks to date palm plants were assessed based on exposure- (AOT40) or flux-based indices (Phytotoxic Ozone Dose, PODy, where y is a threshold of uptake). For this purpose, plants were exposed to three levels of O3 [ambient air, AA (45 ppb as daily average); 1.5 × AA; 2.0 × AA] for 92 days in an O3 Free-Air Controlled Exposure facility. According to the model simulations, the negative effects of O3 on plant-level net photosynthetic CO2 uptake were attributed to reduced gross photosynthetic carbon gain and increased respiratory carbon loss. Season-long O3 exposure and elevated temperatures promoted the negative O3 effect because of a further increase of respiratory carbon loss, which was caused by increased leaf temperature due to stomatal closure. POD1 nonlinearly affected the photosynthetic CO2 uptake, which was closely related to the variation of dry mass increment during the experiment. Although the dose-response relationship suggested that a low O3 dose (POD1 < 5.2 mmol m−2) may even positively affect photosynthetic CO2 uptake in date palms, stomatal O3 uptake at the current ambient O3 levels has potentially a negative impact on date palm growth. The results indicate 5.8 mmol m−2 POD1 or 21.1 ppm h AOT40 as critical levels corresponding to a 4% reduction of net CO2 uptake for date palm, suggesting that this species can be identified as a species moderately sensitive to O3.

Influence of low-energy supersymmetric vector-like quirk particles on W mass increment and muon g–2 anomaly* *Supported by the National Natural Science Foundation of China (12075213)

In the low energy realization of the quirk assisted Standard Model, the couplings between the exotic particles "quirks" and gauge bosons may contribute to the W mass and muon anomaly reported by FermiLab. We calculate the contributions from supersymmetric quirk particles as an example. By imposing the theoretical constraints, we determined that the CDF II W-boson mass increment strictly constrains the mixing and coupling parameters and the quirk mass , while the muon anomaly cannot be solely attributed to the involvement of exotic particles, considering their significantly large masses.

Improvement in myocardial energetics and perfusion with Liraglutide in patients with type 2 diabetes- A randomised, single centre, open label, cross-over drug trial

Abstract Background Both the insulin secretion and insulin resistance in Type 2 diabetes (T2D) are amenable to pharmacological intervention. In a single center, open-label, randomized, cross-over design trial we sought to compare two distinct glycaemic control strategies of targeting beta-cell dysfunction and promoting insulin secretion using Glucagon-like peptide-1 receptor agonists (GLP-1RA) -liraglutide and targeting peripheral insulin resistance using a peroxisome proliferator activated receptor-gamma agonist (PPAR-g)-pioglitazone to see which results in greater improvements in myocardial perfusion, energetics and function in patients with T2D. Methods Fifty-two T2D patients were screened. Eligible patients with no known prior cardiovascular disease were randomized in a 1:1 ratio to be administered one of the study drugs for a 16-week treatment period followed by an 8-week washout and a further 16-week treatment period for the second drug. Thirty-three eligible participants completed both treatment periods. Participants have undergone 31phosphorus magnetic resonance spectroscopy (31P-MRS) at rest and dobutamine stress followed by the cardiac magnetic resonance (CMR) scans. The CMR protocol consisted of rest and dobutamine stress cine imaging, perfusion imaging (motion corrected, automated in-line perfusion mapping), velocity-encoded mitral in-flow imaging and late gadolinium enhanced imaging at 3T immediately before commencement and after completion of each treatment arm (four scans per participant). Results Clinical and biochemical characteristics, and CMR/31P-MRS results are provided in Tables 1&amp;2 respectively. Liraglutide therapy resulted in a significant reductions in the body mass index and significant improvements in glycemic control. Both drugs reduced insulin resistance indicated by a reduction in the mean triglyceride index. There were no significant changes in NTproBNP or troponin levels with either drug. Therapy with either drug did not result in a significant change in the LV end-diastolic volume, ejection fraction or global longitudinal shortening. Pioglitazone led to a significant increment in mean LV mass and LV mass index, while no significant effect in myocardial mass or mass index were detected with liraglutide. Liraglutide therapy resulted in increased rest and dobutamine stress energetics, global stress myocardial blood flow and myocardial perfusion reserve index. While pioglitazone treatment showed no significant effect in these parameters, an isolated improvement in the rest diastolic function was detected in this arm. Conclusions In this randomised cross-over design trial we showed for the first time that four months treatment with glucagon like protein 1 receptor agonist liraglutide results in significant improvements in myocardial stress perfusion and energetics. Pioglitazone results in an isolated improvement in rest diastolic funct

Abstract 12365: Liraglutide Improves Myocardial Stress Perfusion and Energetics in Patients With Type 2 Diabetes- A Randomised, Single Centre, Open Label, Cross-Over Drug Trial

Background: Insulin secretion and insulin resistance in Type 2 diabetes (T2D) are amenable to pharmacological intervention. In a single center, open-label, randomized, cross-over drug trial we compared two glycaemic control strategies using Glucagon-like peptide-1 receptor agonists liraglutide and peroxisome proliferator activated receptor-gamma agonist-pioglitazone to see the effect on myocardial perfusion, energetics and function. Methods: Forty-one eligible patients with T2D and no known prior CV disease were randomized in a 1:1 ratio to the study drugs for a 16-week treatment period followed by an 8-week washout and a further 16-week treatment period for the second drug. Participants underwent rest and dobutamine stress 31 phosphorus magnetic resonance spectroscopy followed by CMR scans. The CMR protocol consisted of rest and dobutamine stress cine imaging, perfusion imaging and late gadolinium enhanced imaging immediately before and after each treatment arm. Results: Liraglutide therapy resulted in significant reductions in the body mass index. Pioglitazone led to a significant increment in LV mass. Liraglutide therapy resulted in increased rest and dobutamine stress energetics, global stress myocardial blood flow and myocardial perfusion reserve. With pioglitazone treatment, an isolated increase in the E/A was observed. Conclusions: In this study we showed for the first time that four months treatment with GLP-1RA (liraglutide) results in significant improvements in myocardial perfusion and energetics, while the insulin sensitiser pioglitazone shows no effect in modulation of these parameters.