Mass Loss Research Articles

Challenging Sarcopenia: Exploring AdipoRon in Aging Skeletal Muscle as a Healthspan-Extending Shield

Sarcopenia, characterized by loss of muscle mass, quality, and function, poses significant risks in aging. We previously demonstrated that long-term treatment with AdipoRon (AR), an adiponectin receptor agonist, alleviated myosteatosis and muscle degeneration in middle-aged obese mice. This study aimed to determine if a shorter AR treatment could effectively offset sarcopenia in older mice. Two groups of old mice (20–23 months) were studied, one untreated (O) and one orally-treated with AR (O-AR) at 50 mg/kg/day for three months, compared with control 3-month-old young mice (Y) or 10-month-old young-adult mice (C-10). Results showed that AR remarkably inversed the loss of muscle mass by restoring the sarcopenia index and fiber count, which were greatly diminished with age. Additionally, AR successfully saved muscle quality of O mice by halving the accumulation of tubular aggregates and aberrant mitochondria, through AMPK pathway activation and enhanced autophagy. AR also bolstered muscle function by rescuing mitochondrial activity and improving exercise endurance. Finally, AR markedly curbed muscle fibrosis and mitigated local/systemic inflammation. Thus, a late three-month AR treatment successfully opposed sarcopenia and counteracted various hallmarks of aging, suggesting AR as a promising anti-aging therapy for skeletal muscles, potentially extending healthspan.

Searching for Neutral Hydrogen Escape from the 120 Myr Old Sub-Neptune HIP94235b using HST

HIP94235 b, a 120 Myr old sub-Neptune, provides us the unique opportunity to study mass loss at a pivotal stage of the system’s evolution: the end of a 100 Myr old phase of intense XUV irradiation. We present two observations of HIP94235 b using the Hubble Space Telescope’s Space Telescope Imaging Spectrograph in the Lyα wavelength region. We do not observe discernible differences across either the blue and red wings of the Lyα line profile in and out of transit, and report no significant detection of outflowing neutral hydrogen around the planet. We constrain the rate of neutral hydrogen escaping HIP94235 b to an upper limit of 1013 gs−1, which remains consistent with energy-limited model predictions of 1011 gs−1. The Lyα nondetection is likely due to the extremely short photoionization timescale of the neutral hydrogen escaping the planet’s atmosphere. This timescale, approximately 15 minutes, is significantly shorter than that of any other planets with STIS observations. Through energy-limited mass loss models, we anticipate that HIP94235 b will transition into a super-Earth within a timescale of 1 Gyr.

The influence of acid rain on asphalt and its mixture performance, simulation and micro-mechanism exploration

Acid rain will destroy asphalt roads and affect human production and life. Therefore, this study has designed a new indoor simulated acid rain erosion test, and explored the effects of acid rain on the properties of 70# petroleum asphalt, SBS asphalt and their mixtures and the acid rain erosion mechanism from the micro and macro perspectives. In this paper, the influence of acid rain erosion on the microscopic properties of asphalt has been revealed through microscopic experiments. Through the combination with the basic performance test of asphalt, the effect of acid rain erosion on the conventional properties of asphalt was studied. The effects of acid rain on the properties of road asphalt mixtures were studied by Marshall immersion and high-temperature rutting tests. The results show that there is no obvious chemical reaction between the two kinds of asphalt after acid rain erosion, but the surface structure and morphology have changed significantly. There was a mass loss, the decreases of the softening point and ductility, and an increase of the penetration; the residual stability and high temperature resistance of both asphalt mixtures were reduced. In the worst case, the quality of petroleum asphalt was lost by 82.2%, the softening point and ductility decreased by 9.6% and 16.9% respectively, the penetration degree increased by 3.1% and the residual stability and dynamic stability of petroleum asphalt mixture decreased by 8.82% and 27.9% respectively. The mass loss of SBS asphalt was 82.5%, the softening point and ductility decreased by 5% and 3.3% respectively, the penetration increased by 2.6%, and the residual stability and dynamic stability of SBS asphalt mixture decreased by 4.82% and 25.4% respectively. In general, under the action of acid rain, the performance of 70# oil asphalt, SBS asphalt and their mixtures are affected to varying degrees. The specific performance is to destroy the original shape of asphalt, resulting in the loss of quality of asphalt, the reduction of deformation resistance, high temperature stability and low temperature stability of asphalt, weakening the high temperature stability and water stability of asphalt mixture, and leading to the decline of road performance.

Strength, durability, and toxicity characteristics of water treatment sludge based geopolymers for subgrade application

This study examined the strength, durability and toxicity characteristics of geopolymer made from water treatment sludge (WTS) using fly ash (FA) and ground granulated blast furnace slag (GGBS) as binding materials for the subgrade application. The mechanical properties of WTS-FA-GGBS geopolymers were assessed considering various parameters such as binder proportions, curing period, curing condition, Sodium silicate (SS) to Sodium hydroxide (SH) ratio (i.e. SS/SH), and Sodium hydroxide (NaOH) concentration. The results showed that increasing binder proportions, NaOH concentration, and curing period positively impacted the strength of the WTS-FA-GGBS geopolymer. The unconfined compressive strength (UCS) of the geopolymer samples with an SS/SH ratio of 2.5 showed higher compressive strength than those at an SS/SH ratio of 1. WTS-FA-GGBS geopolymers cured at 100°C showed increased UCS values after 1 to 3 days, but strength decreased after 7 days due to a faster geopolymerisation reaction, resulting in excessive moisture loss and microcracks in the geopolymerized samples. The study also found that all the geopolymer samples met the minimum strength criteria for cement-stabilized mix with a maximum mass loss of 8.17% are well within the specified limits (<14%) as per IRC:37-2018. The California Bearing Ratio (CBR) values of WTS-FA-GGBS geopolymers, which range from 41.11% to 260.32%, surpass the minimum criteria for cement stabilized subgrade or subbase material, as specified by IRC: SP:89-2010. Additionally, the changes during geopolymerization were confirmed by FESEM, EDS, and XRD analysis. The toxicity characteristic leaching procedure (TCLP) test results showed that the amounts of heavy metals in the geopolymer leachate were within the USEPA-mandated limits.

Tribo-performance analysis of HVOF sprayed Colmonoy-88 using the Taguchi method

The current investigation examines the wear performance of High-Velocity Oxygen Fuel coated Colmonoy-88 coating on SS 304. An L9 orthogonal array design based on the Taguchi fractional factorial method was used to create the erosive wear tests. The impact of three parameters, such as impact velocity (100, 120, and 140 m/s), angle of impact (30°, 60°, and 90°), and test duration (10, 15 and 20 min), on wear performance was investigated by analysis of variance. Results show that the impact angle is the most vital factor for mass loss in both SS 304 and Colmonoy-88, followed by impact velocity and time duration. It was revealed that the maximum wear takes place at 30° impact angle in both specimens. The outcomes of the XRD and EDS analysis show that the Colmonoy-88 has a high chromium content, which provides it with exceptional erosion resistance. The Colmonoy-88 wear mechanism involved inter-splat micro-cutting, lips, crack initiations, and craters caused by fly ash particles at varying impact angles.

Investigating episodic mass loss in evolved massive stars

Mass loss during the red supergiant (RSG) phase plays a crucial role in the evolution of an intermediate-mass star; however, the underlying mechanism remains unknown. We aim to increase the sample of well-characterized RSGs at subsolar metallicity by deriving the physical properties of 127 RSGs in nine nearby southern galaxies. For each RSG, we provide spectral types and used MARCS atmospheric models to measure stellar properties from their optical spectra, such as the effective temperature, extinction, and radial velocity. By fitting the spectral energy distribution, we obtained the stellar luminosity and radius for 92 RSGs, finding that ~50% of them have log(L/L⊙) ≥ 5.0 and six RSGs have R ≳ 1400 R⊙. We also find a correlation between the stellar luminosity and mid-IR excess of 33 dusty variable sources. Three of these dusty RSGs have luminosities exceeding the revised Humphreys-Davidson limit. We then derived a metallicity-dependent J − Ks color versus temperature relation from synthetic photometry and two new empirical J − Ks color versus temperature relations calibrated on literature TiO and J-band temperatures. To scale our derived cool TiO temperatures to values that are in agreement with the evolutionary tracks, we derived two linear scaling relations calibrated on J-band and i-band temperatures. We find that the TiO temperatures are more discrepant as a function of the mass-loss rate, and discuss future prospects of the TiO bands as a mass-loss probe. Finally, we speculate that three hot dusty RSGs may have experienced a recent mass ejection (12% of the K-type sample) and classify them as candidate Levesque-Massey variables.

Effect of Lactational Low-Protein Diet on Skeletal Muscle during Adulthood and Ageing in Male and Female Mouse Offspring

Sarcopenia is characterised by the loss of skeletal muscle mass and function, which leads to a high risk of increased morbidity and mortality. Maternal malnutrition has been linked to impaired development of skeletal muscle of the offspring; however, there are limited studies that report the long-term effect of a maternal low-protein diet during lactation on the ageing of skeletal muscles. This study aimed to examine how a maternal low-protein diet (LPD) during lactation affects skeletal muscle ageing in the offspring. Pups born from control mothers were lactated by mothers fed with an LPD. Post-weaning, mice were either maintained on an LPD or switched to a control, normal-protein diet (NPD). In males, an LPD mainly affected the size of the myofibres without a major effect on fibre number and led to reduced grip strength in ageing mice (24 months). Female mice from mothers on an LPD had a lower body and muscle weight at weaning but caught up with control mice at 3 months. During ageing, the muscle weight, myofibre number and survival rate of female pups were significantly affected. These findings highlight the effect of an LPD during lactation on skeletal muscle ageing, the lifespan of offspring and the importance of sexual dimorphism in response to dietary challenges.

Investigation of Corrosion Protection Through CNTs/ CNFs Modified Cement Mortars

background: the performance of nano modified cement based materials is substantial in terms of their mechanical durability and other similar properties that are of great importance in the functional life of cement structures. The motivation of this study is to formulate conclusions concerning the anti-corrosive impact of Carbon nanotubes (CNTs) and Carbon nanofibers (CNFs) on the properties of mortar specimens and respectively on their service life. methods: The nano additives performance, was investigated through Scanning methods, such as X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM) which analyze the microstructure of mortar specimens with 0.1 % wt addition of CNTs and 0.1 % wt addition of CNFs in their synthesis. In addition, other techniques such as total chloride content and gravimetric mass loss measurements, provide a consolidated assessment of the impact of the nano modified cement materials. In particular, (SEM) and (XRD) microstructure analysis results showed that nanoadditives are found as agglomerates in the cement paste, whereas their hydrophobic nature blocks the diffusion of corrosive factors into the cement paste. Additionally, the total chloride content in mortar specimens with CNFs is approximately 50% less than the relevant percentage of the specimens without additives, which is in compliance with the relevant percentages of porosity values. Furthermore, from the elemental analysis of all specimens, it is found that the samples that are corroded are the specimens without nano additives. results: The addition of nanomodified materials affects the porosity and the microstructure of the mortar specimens. conclusion: The addition of 0,1 % of CNTs or CNFs positively affects against corrosion impact while exposure in extremely corrosive conditions.

Modulation of animal and plant tissue growth with collagen‐starch‐organic molybdenum networks hydrogel biomatrices

AbstractThe development of hydrogel biomatrices with potential to modulate animal and plant tissue growth is ongoing. In this study, molybdenum bio‐metal–organic frameworks (MOFs) (Mo‐bioMOFs) incorporating essential amino acids such as l‐histidine (Mo‐His), l‐phenylalanine (Mo‐Phe), and l‐tryptophan (Mo‐Trp) were encapsulated in semi‐interpenetrating polymer network (semi‐IPN) hydrogels composed of collagen and starch. The structure and properties of these materials show dependence on the amino acid that constitutes the Mo‐bioMOFs. The biomatrices have a semi‐crystalline surface with increased porosity when using Mo‐His; this system also benefits swelling. Increased crosslinking, acceleration in gelation, and mechanical improvement are observed for the system based on Mo‐Phe. Methylene blue release experiments were conducted, demonstrating that matrices including Mo‐bioMOFs exhibit controlled release profiles, indicating highly stable retention of Mo‐bioMOFs in the semi‐IPN matrix. The biomatrices enhance the metabolism and proliferation of fibroblasts and monocytes, with Mo‐Trp reducing the secretion of inflammatory cytokines like TNF‐α. The biomatrices exhibit gradual and slow mass loss when exposed to collagenase and commercial vegetable substrates. Both leaf and root cells of tomato plants (Solanum lycopersicum) show increased metabolism and growth when exposed to Mo‐Phe and Mo‐His. Notably, the biomatrix containing Mo‐Phe promotes the most substantial plant growth and foliage after 30 days. These biomatrices have potential applications in chronic wound healing and agriculture.

412. COMPARISON BETWEEN PREOPERATIVE MALNUTRITION, AND SARCOPENIA AND POSTOPERATIVE COMPLICATIONS IN ESOPHAGEAL CANCER PATIENTS

Abstract Background Typical indicators of malnutrition in cancer patients include BMI, CONUT, PNI, and prealbumin, while SMI and PMI are often used as indicators of skeletal muscle mass loss (sarcopenia). Although these indicators have been reported to be associated with surgical outcomes, their combination may be useful in determining the effectiveness of perioperative management because these are closely related during the perioperative period. Methods A total of 132 esophageal cancer patients who underwent esophagectomy between January 2021 and May 2023 were included in this study. Preoperative BMI, CONUT, PNI, prealbumin, SMI (measured by BIA), and PMI (measured by CT imaging) were extracted from clinical record. We also selected BMI and SMI as a new indicator for combined malnutrition and loss of skeletal muscle. Then, we investigated the association between these indicator and postoperative complications (pneumonia, suture failure, total CD Grade ≥II, total CD ≥IIIa), and length of hospital stay. Results The mean age of patients was 67.3 years, 107 were male and 25 were female. Preoperative chemotherapy was administered to 58 patients. Although associations with each single index were found for postoperative pneumonia and low BMI, low SMI, and low PMI, there was no significant association with anastomotic leakage or overall complications. On the other hand, low BMI+SMI was strongly correlated with postoperative pneumonia, overall Grade≥II, and Grade≥IIIa complications. In postoperative hospital stay, low BMI, low PNI, and low SMI as single indicators showed a significant increase in hospital stay, while low BMI+SMI showed further statistically significant increase. Conclusion In patients who underwent esophagectomy, single index for malnutrition and low skeletal muscle mass may be predictors of postoperative complications respectively. However, because perioperative management is inseparable from nutritional therapy and exercise therapy, composite index of BMI and SMI may be better predictor of therapeutic efficacy of perioperative nutrition and exercise therapy.

Porous concrete modification with silica fume and ground granulated blast furnace slag: Hydraulic and mechanical properties before and after freeze-thaw exposure

This study investigates the effects of incorporating silica fume (SF) and ground granulated blast furnace slag (GBFS), both individually and in hybrid combinations, on various properties of porous concrete (PC) were evaluated under room conditions and after freeze-thaw (F-T) cycles. The hardened density (HD), water permeability coefficient (k), apparent porosity (AP), as well as compressive strength (CS), splitting tensile strength (STS), and flexural strength (FS) at 7, 28, and 120 days. Additionally, the impact of SF and GBFS on the mass loss (ML), residual compressive strength (RCS), residual splitting tensile strength (RSTS), and residual flexural strength (RFS) of PC samples subjected to 30, 60, 120, and 180 freeze-thaw (F-T) cycles was analyzed. The findings revealed that the addition of SF and GBFS decreased the AP and k values of PC samples under room conditions. Furthermore, these materials significantly improved the CS, STS, and FS properties of PC samples, especially at the 28-day and 120-day marks, owing to their enhanced pozzolanic activity over time. SF and GBFS also contributed to higher RCS, RSTS, and RFS values in PC samples after F-T cycles compared to the control samples. This was due to their effective gap-filling properties and the formation of additional calcium-silicate-hydrate (C-S-H) gels within the matrix. Additionally, SF and GBFS led to slightly higher RDME values in the C1-C6 samples than in the control samples following F-T cycles. However, SF and GBFS did not have a significant impact on reducing the ML values of PC samples after F-T cycles.

CO2 treatment of recycled concrete aggregates with high mortar contents: From finding optimal treatment condition, quality enhancement, to life cycle assessment

With increasing construction and demolition waste, the demand for recycled concrete aggregates (RCA) has risen, yet their inherent poor-quality limits usage. In response, CO2 treatment has been developed to enhance RCA quality while contributing to CO2 reduction efforts. This study investigates the effect of CO2 treatment on RCA with high mortar contents for sustainable construction applications. Treatment conditions were optimized by evaluating the CO2 consumption ratio and reaction kinetics under various temperatures (10–50°C), pressures (250–1000 kPa), relative humidity (30–70 %), and initial saturation (30–100 %). X-ray imaging confirms carbonation within the mortar, evidenced by increased greyvalues. Environmental assessment of leachate reveals a significant reduction in chromium concentration from 0.18 mg/L to 0.11 mg/L and a decrease in pH from 10.1 to 7.8 after CO2 treatment, suggesting the potential of CO2 conditioning to mitigate the environmental impacts. Mechanical tests, the aggregate crushing value (ACV) test, and the freeze-thaw (FT) resistance test, demonstrate the improved resistance and durability, with a decrease in ACV from 35.5 % to 33.2 % and FT mass loss from 25.1 % to 20.0 %. The life cycle assessment analysis shows that a simplified CO2 treatment achieved a significant reduction of 138.257 kg CO2 eq per ton of RCA compared to the conventional RCA process. These findings highlight the dual benefits of CO2 treatment: enhanced mechanical performance and reduced environmental impact, promoting the use of recycled aggregates in sustainable construction practices.

The progenitor star of SN 2023ixf: A massive red supergiant with enhanced, Episodic Pre-Supernova mass loss

Abstract We identify the progenitor star of SN 2023ixf in Messier 101 using Keck/NIRC2 adaptive optics imaging and pre-explosion HST/ACS images. The supernova, localized with diffraction spikes and high-precision astrometry, unambiguously coincides with a progenitor candidate of mF814W = 24.87 ± 0.05 (AB). Given its reported infrared excess and semi-regular variability, we fit a time-dependent spectral energy distribution (SED) model of a dusty red supergiant (RSG) to a combined dataset of HST optical, ground-based near-infrared, and Spitzer/IRAC [3.6], [4.5] photometry. The progenitor resembles a RSG of Teff = 3488 ± 39 K and log (L/L⊙) = 5.15 ± 0.02, with a 0.13 ± 0.01 dex (31.1 ± 1.7 per cent) luminosity variation at a period of P = 1144.7 ± 4.8 days, obscured by a dusty envelope of τ = 2.92 ± 0.02 at 1 μm in optical depth (or AV = 8.43 ± 0.11 mag). The signatures match a post-main sequence star of $18.2_{-0.6}^{+1.3}\, \mathrm{M}_\odot$ in Zero-Age Main Sequence mass, among the most massive SN II progenitor, with a pulsation-enhanced mass-loss rate of $\dot{M}=(4.32\pm 0.26)\times 10^{-4} \, \mathrm{M}_\odot \, \text{yr}^{-1}$. The dense and confined circumstellar material is ejected during the last episode of radial pulsation before the explosion. Notably, we find strong evidence for variations of τ or Teff along with luminosity, a necessary assumption to reproduce the wavelength-dependent variability, which implies periodic dust sublimation and condensation. Given the observed SED, partial dust obscuration remains possible, but any unobstructed binary companion over 5.6 M⊙ can be ruled out.

Reductions in functional muscle mass and ability to ambulate in Duchenne muscular dystrophy from ages 4 to 24 years.

Duchenne muscular dystrophy (DMD) results in a progressive loss of functional skeletal muscle mass (MM) and replacement with fibrofatty tissue. Accurate evaluation of MM in DMD patients has not previously been available. Our objective was to measure MM using the D3creatine (D3Cr) dilution method and determine its relationship with strength and functional capacity in patients with DMD over a wide range of ages. Subjects were recruited for participation in a 12month, longitudinal, observational study. Here, we report the baseline data. A 20mg dose of D3Cr dissolved in water was ingested by 92 patients with DMD (ages 4-25years) followed later with a fasting urine sample. Enrichment of D3creatinine was determined by liquid chromatography-mass spectrometry analysis. The North Star Ambulatory Assessment (NSAA) total score was determined for ambulatory participants, and the Performance of Upper Limb (PUL 2.0) total score and grip strength for all participants. We observed a significant age-associated increase in body weight along with a substantial decrease in MM/body weight (%MM). MM and %MM were associated with PUL score (r=0.517, P<0.0001 and r=0.764, P<0.0001 respectively). The age-associated decrease in MM and %MM was strongly associated with ambulatory status. We observed very little overlap in %MM between ambulant and non-ambulant subjects, suggesting a threshold of 18-22% associated with loss of ambulation. MM is substantially diminished with advancing age and is highly related to clinically meaningful functional status. The D3Cr dilution method may provide a biomarker of disease progression and therapeutic efficacy in patients with DMD or other neuromuscular disorders. KEY POINTS: The non-invasive D3creatine dilution method provides novel data on whole body functional muscle mass (MM) in a wide range of ages in patients with DMD and reveals profoundly low functional MM in older non-ambulant patients. The difference in %MM between ambulant and non-ambulant subjects suggests a threshold for loss of ambulatory ability between 18 and 22% MM. The data suggest that as functional MM declines with age, maintaining a lower body weight may help to conserve ambulatory ability.

Protein intake by master swimmers: Implications for practice in Sports Nutrition-A cross-sectional study.

Background: Proteins are essential for the maintenance, repair, and growth of muscle mass. This is particularly important for master athletes because aging has been associated with loss of muscle mass, function, and strength. Moreover, the timing of intake has been shown important for the best protein utilization. Aim: To analyze timing, quantity, and source of dietary protein in competitive master athletes according to current recommendations. Methods: Twenty-one male master swimmers (47.9 ± 10.0 years; 79.2 ± 6.5 kg; 179.1 ± 5.5 cm; 23.5 ± 4.9% body fat; 73.3 ± 4.2% lean mass) participated in this cross-sectional study. Protein intake was analyzed based on 7-day food records, regarding quantity, timing, and sources of intake. Protein intake was evaluated according to current international sports nutrition guidelines, including the International Society of Sports Nutrition Position Stand. Body fat (%) and lean mass (%) were evaluated using dual-energy X-ray absorptiometry. Results: Participants' mean protein intakes were 1.9 ± 0.5 g/kg/day, 0.6 ± 0.2 g/kg/meal post-training, and 33.5 ± 23.9 g during the pre-sleep period. Daily intake was within the recommended values of 1.4 and 2.0 g/kg/day (p = 0.01 and 0.147, respectively). Mean pre-sleep intake was within the recommendation values of 30-40 g (p = 0.28 and 0.147, respectively). Most of the daily protein intake was consumed at lunch (66.7 ± 6.9 g) and dinner (48.0 ± 4.5 g). Regarding protein sources, intakes from animal, vegetal, and supplements were, respectively, 65.7%, 29.2%, and 5.1%. Conclusion: Master swimmers presented a total protein intake within the recommendations for a daily basis, but the majority of intake was at lunch and dinner. Protein intake could be better distributed throughout the day to optimize protein synthesis. Guidance on daily protein intake distribution should be reinforced in clinical practice.

Waste glass as an eco-friendly substitute in plastering mortars: analyzing microstructure, thermal, and mechanical properties

This study investigates waste glass (WG) as an environmentally friendly substitute for natural sand in cement mixtures. Plastering mortars were fabricated by replacing sand with WG at proportions of 10%, 20%, and 30%. X-ray diffraction, Thermogravimetry, Scanning Electron Microscopy, and Energy-dispersive X-ray spectroscopy characterized the mortars. Compressive strength was measured at two ages (7 and 28 days) for WG-containing mortars. Results confirm the suitability of waste glass as a sand replacement in mortars, with the 20% WG sample showing optimal compressive strength, contributing to environmental and economic impact reduction. Thermogravimetric analysis of the 30% WG mortar shows a significant difference in mass loss percentages compared to the reference mortar, losing only 3.65% at 28 days versus 7.85%. Additionally, waste glass increased mortar density, reducing porosity and enhancing structural uniformity. Despite a decrease in compressive strength values, the results remain satisfactory for application in the Civil Construction industry. This comprehensive exploration underscores the potential of waste glass as a sustainable alternative, emphasizing its positive effects on both performance and environmental considerations.

Study on the damage mechanism of hydraulic concrete under the alternating action of freeze-thaw and abrasion

This study investigates the damage mechanism of hydraulic concrete under the alternating action of freeze–thaw (F) and abrasion (W) in cold regions. To this end, three groups of working conditions were established with a constant water-binder ratio. The mass loss and relative dynamic elastic modulus (RDEM) of each cycle were evaluated using the fast-freezing method and underwater method. The phase composition and relative content change of hydration products, pore characteristic parameters and pore size distribution, morphology and microstructure of interfacial transition zone (ITZ) were analyzed by X-ray diffraction (XRD), mercury intrusion porosimeter(MIP), scanning electron microscopyn (SEM) and image recognition technology, respectively. The results indicate that the alternating effect will accelerate the mass loss of concrete and the reduction of the RDEM compared with the single factor. Following four consecutive alternating cycles, the mass loss rates of working conditions W and F group were found to be 4.61 % and 97.66 % lower, respectively, than those of working condition F-W group. The RDEM damage coefficient (γ < 1) was also observed. At the micro level, the freeze-thaw effect will result in the formation of a considerable number of micropores and the expansion of microcracks, with the abrasion effect continuing to promote this process. In the process of alternating action, the dissolution of Ca(OH)2 by external water through microcracks and interconnected pores is accelerated. Concurrently, the pores and microcracks in the ITZ expand, the morphology is roughened, and the microstructure is complicated. The interfacial bonding ability and compactness of different material components decrease. Under the action of external disturbance, cement paste and aggregate fall off, resulting in mass loss and a decreased RDEM.

Getting slimmer without dieting or exercising: zebra finches can rapidly lose mass while maintaining food intake and decreasing activity.

It is widely accepted that birds can adaptively regulate body mass in different ecological contexts, but little is known about how birds monitor and interpret their body mass or the mechanisms that allow for rapid changes in mass. Using captive zebra finches (Taeniopygia guttata), we experimentally increased perceived mass via attachment of weighted backpacks and provided birds with either an ad libitum mixed-seed diet or supplementary high-fat diet to investigate (a) how birds assess their own body mass and (b) the physiological and/or behavioral mechanisms birds may employ to rapidly adjust body mass. In both experiments, and independent of diet treatment, birds with weighted backpacks rapidly lost mass within two days of backpack attachment while reducing overall activity and maintaining food intake. Additionally, our data suggest that birds interpret body mass via a physical mechanosensory pathway rather than a physiological pathway: rapid loss of mass between days 0 and 2 was not linked to changes in plasma metabolites (glycerol or triglyceride concentrations). We found no evidence that mass loss was a consequence of stress associated with attachment of weighted backpacks (based on plasma corticosterone measures). Our results suggest that the processes of energy balance and mass regulation involve a greater array of mechanisms than simply matching energy in through the amount of food consumed to energy out, dictated by activity: zebra finches were able to decrease body mass through other, unidentified, mechanisms even while maintaining dietary intake and reducing overall activity.

Industrial manufacturing method and characterization of Ayurvedic marine drugs: mother pearl, cowry, coral and pearl

Introduction: Ayurvedic marine drugs derived from mollusc shells and coral are regularly used by Ayurvedic physicians to treat several disease conditions like acid peptic disease, irritable bowel syndrome, osteoporosis, etc. However, standard operating procedures for manufacturing these drugs and their complete characterization have not been published in the Ayurvedic Formulary and Ayurvedic Pharmacopeia of India to date. Methods: Present study describes the traditional manufacturing process and thorough characterization using classical and advanced analytical tools. The raw materials characters, in-process parameters, and finished product specifications have been elaborated to develop monographs. Especially, the identity and purity of raw coral and pearl were checked by Raman Spectroscopy and Energy Dispersive X-ray Fluorescence analysis. Results: In the finished product analysis, the X-Ray Diffraction study revealed that incineration after trituration with Aloe barbadensis leaf pulp or rose water converted the aragonite phase of calcium carbonate into calcite phase in mother pearl, cowry, and pearl while the calcite form of raw coral was retained. The prominent bands around 1390, 870, and 712 cm−1 detected by Fourier Transform-Infrared Spectroscopy and mass loss between 39–44% (w/w) revealed by thermogravimetric analysis confirmed the carbonate form of these calcium-based drugs. The finished products were very fine grayish-white powders constituted by irregularly shaped nano-micro particulate calcium carbonate exhibiting particle size between 600 nm (D10 value) to 1.2 µm (D90 value). Conclusion: The quality control and assurance achieved in this study may be further utilized by the pharmaceutical industries to manufacture quality marine drugs and conduct efficacy studies.

Adiabatic Mass Loss in Binary Stars. IV. Low- and Intermediate-mass Helium Binary Stars

The unstable mass transfer situation in binary systems will asymptotically cause the adiabatic expansion of the donor star and finally lead to the common envelope phase. This process could happen in helium binary systems once the helium donor star fills its Roche-lobe. We have calculated the adiabatic mass-loss model of naked helium stars with a mass range of 0.35 M ⊙–10 M ⊙, and every mass sequence evolved from the helium-zero-age main sequence to the cooling track of white dwarf or carbon ignition. In consideration of the influence of stellar wind, massive helium stars are not considered in this paper. Comparing the stellar radius with the evolution of the Roche-lobe under the assumption of conservative mass transfer, we give the critical mass ratio q crit = M He/M accretor as the binary stability criteria of low- and intermediate-mass helium binary stars. On the helium main sequence, the result shows 1.0 < q crit < 2.6, which is more unstable than the classical result of polytropic model q crit = 3. After the early helium Hertzsprung Gap, the q crit quickly increases even larger than 10 (more stable compared with the widely used result of q crit = 4), which is dominated by the expansion of the radiative envelope. Our result could be useful for these quick mass transfer binary systems such as AM CVns, ultra-compact X-ray binaries, and helium novae, and it could guide the binary population synthesis for the formation of special objects such as type Ia supernova and gravitational wave sources.