Regression Of Mass Research Articles

Mass changes and energetic condition of grassland and shrubland songbirds during autumn stopovers at a reclaimed landfill in the New Jersey meadowlands

ABSTRACT Former landfills have long been recognized as a potential source of early successional habitat for wildlife, but their use by migrating grassland and shrubland songbirds has yet to be studied. We estimated mass change rates of 5 grassland and shrubland songbird species during autumn stopovers at a reclaimed landfill in New Jersey, to assess the quality of a former landfill as a stopover habitat. We also examined minimum length of stay, age ratios, and age differences in body mass and fat scores. Regressions of capture time and body mass were statistically significant and indicated gains of 0.8–1.2% of average body mass per hour in Savannah Sparrows (Passerculus sandwichensis), Lincoln's Sparrows (Melospiza lincolnii), and Palm Warblers (Setophaga palmarum), but coefficients of determination were weak (<0.06). White-crowned Sparrows (Zonotrichia leucophrys leucophrys) and Indigo Buntings (Passerina cyanea) did not gain significant mass. Minimum length of stay based on recaptures ranged from an ave...

Real role of β-blockers in regression of left ventricular mass in hypertension patients: Bayesian network meta-analysis: Erratum.

Real role of β-blockers in regression of left ventricular mass in hypertension patients: Bayesian network meta-analysis: Erratum.

Real-time whole-body motion generation using torso posture regression and center of mass

For household humanoid robots, reaching as much workspace as possible with their hands is an important issue because the locations of target objects may range from the floor to above the robot’s head. At the same time, to adapt to the constantly-changing household environment, inverse kinematics for the whole body must be solved in real time. In this paper, to achieve real-time motion generation for a humanoid robot, we propose a method of separating the inverse kinematics calculation into simpler problems. Using regression to estimate the torso orientation, we independently solve inverse kinematics for the lower body and both arms. First, using the target pose of both hands as input, we calculate the orientation of the torso and determine the target position of the center of mass considering the reachability of both arms. At each control step, we calculate the joint angles of the lower body from the position of the center of mass, feet poses, and torso orientation. Then, we calculate the joint angles of both arms. In experiments, we apply the proposed method to a human-size humanoid robot for reaching low-height positions while hunkering down. The proposed inverse kinematics solver is ten times faster than the numerical solution using the Jacobian matrix. We also verify the applicability of the proposed method using a sequence of random target positions for the hands as input.

Changes in Biomarker Profile and Left Ventricular Hypertrophy Regression: Results from the Frequent Hemodialysis Network Trials

Background: Regression of left ventricular hypertrophy (LVH) is feasible with more frequent hemodialysis (HD). We aimed to ascertain pathways associated with regression of left ventricular mass (LVM) in patients enrolled in the Frequent HD Network (FHN) trials. Methods: This was a post hoc observational cohort study. We hypothesized LVH regression with frequent HD was associated with a different cardiovascular biomarker profile. Regressors were defined as patients who achieved a reduction of more than 10% in LVM at 12 months. Progressors were defined as patients who had a minimum of 10% increase in LVM at 12 months. Results: Among 332 randomized patients, 243 had biomarker data available. Of these, 121 patients did not progress or regress, 77 were regressors, and 45 were progressors. Mean LVM change differed between regressors and progressors by –65.6 (–74.0 to –57.2) g, p < 0.001. Regressors had a median (interquartile range) increase in dialysis frequency (from 3.0 [3.0–3.0] to 4.9 [3–5.7] per week, p = 0.001) and reductions in pre-dialysis systolic (from 149.0 [136.0–162.0] to 136.0 [123.0–152.0] mm Hg, p < 0.001) and diastolic (from 83.0 [71.0–91.0] to 76.0 [68.0–84.0] mm Hg, p < 0.001) blood pressures. Klotho levels increased in regressors versus progressors (76.9 [10.5–143.3] pg/mL, p = 0.024). Tissue inhibitors of metalloproteinase (TIMP)-2 levels fell in regressors compared to progressors (–7,853 [–14,653 to –1,052] pg/mL, p = 0.024). TIMP-1 and log (brain natriuretic ­peptide [BNP]) levels also tended to fall in regressors. Changes in LVM correlated inversely with changes in klotho (r = –0.24, p = 0.014). ­Conclusions: Markers of collagen turnover and changes in klotho levels are potential novel pathways associated with regression of LVH in the dialysis population, which will require further prospective validation.

Allometric and Biphasic Allometric Growth of Major Organs in Hatchling Female Alligators (Alligator mississippiensis)

Allometric equations represent relationships between a morphological size (e.g., organ size) or physiological rate (e.g., metabolic rate) and body mass using the equation Y=aMb, where Y is morphological size or physiological rate, a is elevation or y‐intercept, b is slope and M is animal body mass. Vertebrate organ growth relative to body mass varies between allometric (b&lt;1.0 or b&gt;1.0) and isometric (b=1.0), depending on the organ and species. In mammals and reptiles, heart and lungs have been shown to grow isometrically, whereas in mammals, the kidneys and liver have been shown to grow with negative allometry. Most allometric studies of organ growth focus on changes that span orders of magnitude achieved between juvenile and adult life stages or between various species of widely divergent size. This may ignore or possibly ‘wash out’ trends that occur during rapid growth in very early life stages. Large avian species and reptiles grow most rapidly during their early life history, and there can be significant genetic or ‘clutch’ effects for reptiles with different parentage. Large crocodilians, like the American alligator, can increase in size by a factor of &gt;10 during their first year post‐hatching and show physiological differences between clutches that persist at least through the first year post‐hatching. We measured organ growth in hatchling female alligators from 5 clutches at 8–10 time points during their first order of magnitude of growth (~45 g to ~500 g). We tracked each individual alligator (N&gt;90) from their original egg identity (clutch and egg mass). Animals were anesthetized and sacrificed, and their organs carefully dissected. Organ and animal wet masses (±0.1 mg and ±0.1 g, respectively) were measured upon sacrifice, and dry masses were measured after organs and the animal's carcass had fully dried (2d ‐ several weeks at 70°C) so that mass did not change by &gt;1% between &gt;18‐h spaced measurements. Slopes and intercepts for regressions of organ mass against body mass were compared among clutches using ANCOVA. Breakpoint analyses determined the intersection with minimum residual sum of squares or the intersection where the differences of the residual variances were smallest. Preliminary data showed that dry kidney and liver size increased in relative proportion to body mass (b~1.0), and heart size (b~0.9) and lung size (b~0.75) decreased in relative proportion. Dry masses showed less variation compared to wet masses. Within the first order of magnitude of growth, breakpoint analyses revealed that kidney and liver mass grew more quickly during the hatchlings first weeks‐to‐months post‐hatching, and our study is the first to document biphasic organ growth in hatchlings of a large, long‐lived reptile. Hatchling alligators appear to undergo a very early period of rapid kidney and liver growth following hatching, and these two organs grow with different kinetics than lung or heart tissue. Reasons for this disparity will be an area of further research.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Renal Artery Denervation Due to Refractory Hypertension in a Patient After Kidney Transplantation—3 Years of Observation: A Case Report

IntroductionHypertension is prevalent in most patients after renal transplantation, and it is the main factor contributing to cardiovascular diseases that cause death of a significant number of these patients. Up to 95% of patients after transplantation have hypertension, and among them are patients with refractory hypertension. Elevated blood pressure is one of the causes of deterioration of transplant function and may accelerate transplant loss. Case ReportWe present the first case in the world of a patient (who was 61 years old) in whom denervation of native renal arteries was performed after renal transplantation (2004). The patient was suffering from uncontrolled refractory hypertension. Antihypertensive therapy was used but the effect was not satisfactory. The patient received amlodipine, bisoprolol, clonidine, furosemide, and doxazosin in high doses. Clinical assessments with ambulatory blood pressure monitoring revealed a predominant blood pressure 149/96 with incidents of hypertensive crises. High blood pressure is a cardiovascular risk factor and it also has a significant influence on transplant failure, which was the reason for performing the denervation. The procedure was carried out through the femoral artery with the use of a 6F guiding catheter. During a 3-year observation, significant decreases in ambulatory blood pressure monitoring systolic and diastolic blood pressures were observed after the procedure (149/96 mm Hg vs 134/91 mm Hg before and after the denervation, respectively). There was a significant regression of left ventricle mass (577 g before denervation vs 470 g after 3 years). The functioning of the renal transplant became stable after 3 years of observation (38 mL/min before denervation and 38 mL/min after 3 years). ConclusionsThe first case in the world of a renal transplant patient who had denervation of native renal arteries has demonstrated a positive effect in controlling blood pressure over a 3-year observation. Three years after denervation, a reduction of heart hypertrophy and stabilization of renal function were noted. The presented case shows that denervation of native renal arteries denervation may be successful and safe in kidney transplant recipients.

When is more frequent hemodialysis beneficial?

The use of frequent hemodialysis (HD) is growing, with the hope of improving outcomes in end-stage renal disease. We narratively review the three randomized trials, 15 comparative cohort studies, and several case series of frequent HD that empirically demonstrate the potential efficacy and adverse effects of these regimens. Taken together, the randomized studies suggest frequent HD may result in left ventricular mass regression. This effect is most pronounced when left ventricular mass is abnormal, but attenuated by significant residual urine output. Both frequent short and long HD consistently improved blood pressure control and reduced antihypertensive use, despite greater weekly interdialytic weight gains. Serum phosphate was lowered. Frequent short daytime HD improved health-related quality of life, while frequent long overnight HD did not. Regarding adverse effects, frequent HD patients underwent significantly more procedures to salvage arteriovenous vascular accesses. An absolute increase in hypotensive episodes was observed with frequent short HD, while frequent long HD accelerated residual renal function loss and increased perceived caregiver burden. The effect of frequent HD on mortality is controversial, due to conflicting results and limitations of published studies. Finally, pregnancy outcomes may be substantially better with frequent long HD. On the basis of these data, we suggest frequent HD is most likely to benefit patients with left ventricular hypertrophy particularly if there is minimal urine output, those unable to attain dry weight on a thrice weekly schedule, and pregnant women. All patients receiving frequent HD should be advised of and monitored for potential risks.

24-hour urine adequacy: Use of a lean muscle mass regression based model

24-hour urine adequacy: Use of a lean muscle mass regression based model

THE IMPACT OF VALVULOARTERIAL IMPEDANCE ON THE LEFT VENTRICULAR MYOCARDIAL REGRESSION AFTER TRANSCATHETER AORTIC VALVE REPLACEMENT: A COMPARISON WITH TRANSVALVULAR MEAN PRESSURE GRADIENT

Left ventricular hypertrophy is associated with poor prognosis in aortic stenosis. Left ventricular mass regression observed after transcatheter aortic valve replacement (TAVR) is presumed to result in reduction of left ventricular stress. Valvuloarterial impedance (Zva) is a surrogate marker of

IMPACT OF METABOLIC SYNDROME AND/OR DIABETES ON LEFT VENTRICULAR MASS IN PATIENTS WITH SEVERE AORTIC STENOSIS BEFORE AND AFTER AORTIC VALVE REPLACEMENT

In aortic stenosis (AS), metabolic syndrome (MetS) and diabetes mellitus (DM) are associated with more left ventricular (LV) hypertrophy. We aimed to examine the impact of MetS/DM on LV mass in patients with severe AS referred to aortic valve replacement (AVR) and on the LV mass regression after AVR

Drivers of in vivo bite performance in wild brown mouse lemurs and a comparison with the grey mouse lemur

AbstractPhysical performance is crucial for animal survival and fitness. In this context, greater bite forces can provide advantages and may allow an individual to gain access to reproductive partners and/or different food resources. Here, we explored the determinants of bite force in a wild population of the brown mouse lemur (Microcebus rufus). Our objectives were to elucidate (1) if sex, head width, heart rate (as an indicator of overall physical fitness) and body condition drive variation in bite force in this population of wild mouse lemurs; and (2) the relative importance of the ecological niche in determining bite force by comparing results from this wild population with previously published results on bite force, body mass and head width from a laboratory colony of the grey mouse lemur (Microcebus murinus). We captured 32 wild brown mouse lemurs at night in the Ranomafana National Park in Madagascar during the beginning of the rainy season from 1st to 31st October 2016. We measured bite force, heart rate, body mass and head width of all individuals, and assigned sex and body condition (estimated as the unstandardized residual of a regression of body mass against head size). Although maximum bite force was positively correlated with body mass, it was not correlated with body condition. Residual bite force was highly correlated with residual head width and heart rate. The mean bite force of wild brown mouse lemurs was much lower than that of grey mouse lemurs in captivity, but showed similar relationships to head dimension and body mass. Even when corrected by body condition, grey mouse lemurs bit significantly harder than brown mouse lemurs. The difference in bite force between species could be explained by differences in head size and niche divergence with brown mouse lemurs eating mostly soft fruits and grey mouse lemurs eating more hard insects.

Mass‐independent maximal metabolic rate predicts geographic range size of placental mammals

Abstract Understanding the mechanisms driving geographic range sizes of species is a central issue in ecology, but remarkably few rules link physiology with the distributions of species. Maximal metabolic rate (MMR) during exercise is an important measure of physiological performance. It sets an upper limit to sustained activity and locomotor capacity, so MMR may influence ability to migrate, disperse and maintain population connectivity. Using both conventional ordinary least squares (OLS) analyses and phylogenetically generalized least squares (PGLS), we tested whether MMR helps explain geographic range size in 51 species of placental mammals. Log body mass alone (OLS r2 = .074, p = .053; PGLS r2 = .016, p = .373) and log MMR alone (OLS r2 = .140, p = .007; PGLS r2 = .061, p = .081) were weak predictors of log range size. However, multiple regression of log body mass and log MMR accounted for over half of the variation in log range size (OLS R2 = .527, p &lt; .001). The relationship was also strong after correcting for the phylogenetic non‐independence (PGLS R2 = .417, p &lt; .001). In analyses restricted to rodents (34 species), neither log body mass alone (OLS r2 = .004, p = .720; PGLS r2 = .003, p = .77) nor log MMR alone was useful in predicting log geographic range size (OLS r2 = .008, p = .626; PGLS r2 = .046, p = .225), but multiple regressions of log body mass and log MMR accounted for roughly a third to a half of the variation in log range size (OLS R2 = .443, p &lt; .001, PGLS R2 = .381, p &lt; .001). Mass‐independent MMR is a strong predictor of mass‐independent geographic range size in placental mammals. The ability of body mass and MMR to explain nearly 50% of the variation in the geographic ranges of mammals is surprising and powerful, particularly when neither variable alone is strongly predictive. A better understanding of MMR during exercise may be important to understanding the limits of geographic ranges of mammals, and perhaps other animal groups. A plain language summary is available for this article.

Fat reserve assessment in Pyrenean chamois using body measurements

Body condition is a measure of the energetic reserves stored in tissues and organs of animals in anticipation of periods of special energetic demands or to attenuate food shortages. For more than half a century, the kidney fat index (KFI) has been the most common invasive method for assessing body condition in ungulates. Since KFI requires animal necropsy, other non-invasive indicators based on body measurements have been suggested to assess body condition of mammals. These include the residuals from an ordinary least squares regression of body mass and linear measure of size (OLSr), the scores from a Principal Components Analysis on body measurements (PCAsc), and the scaled mass index (SMI). These indices, however, are often difficult to interpret and little effort has been made to confirm whether they are related to direct measures of fat reserves. We used the Bland-Altman method and linear models applied to biometric data to explore whether these three biometric indices can be used to assess body condition in 94 adult male and female Pyrenean chamois (Rupicapra pyrenaica pyrenaica). Animals were hunter-harvested in the Eastern Pyrenees (Spain) during two contrasting periods of food availability. We found that OLS residuals from the regression between body weight and hind foot length were the best proxy for fat reserves in both periods of the year. This simple, low cost and non-invasive biometric indicator can be used for monitoring body condition of chamois populations and probably in other ungulate species with similar life strategies.

Freedom Solo® versus Trifecta® bioprostheses: clinical and haemodynamic evaluation after propensity score matching.

The goal of this study was to compare the stentless Freedom Solo® (FS) and the stented Trifecta® (TF) aortic bioprostheses with regard to haemodynamic profile, left ventricular mass regression and early and late postoperative outcomes and survival. A longitudinal cohort study of consecutive patients undergoing aortic valve replacement (2009-16) with either the FS or TF at 1 centre was performed. Local databases and national records were queried. Prosthesis haemodynamics and left ventricular dimensions were obtained from postoperative echocardiograms. After propensity score matching (21 covariates), the Kaplan-Meier and competing risk analyses were performed for survival and the combined outcome of structural valve deterioration and endocarditis, respectively. Haemodynamics and mass regression were assessed by a mixed-effects model including propensity score as a covariate. From a total sample of 397 patients with the FS and 525 TF bioprostheses with a median follow-up time of 4.0 (2.2-6.0) and 2.4 (1.4-3.7) years, respectively, a matched sample of 329 pairs was obtained. Matched groups showed no differences in survival (hazard ratio = 1.04, 95% confidence interval = 0.69-1.56) or cumulative hazards of combined outcome (subdistribution hazard ratio = 0.54, 95% confidence interval = 0.21-1.39). Although the TF showed an improved haemodynamic profile, no difference was found in mass regression. Patients with TF bioprostheses had higher rates of prolonged mechanical ventilation, whereas patients with the FS bioprosthesis showed higher rates of thrombocytopenia. The TF showed an improved haemodynamic profile compared to the FS, but this did not translate into further reverse remodelling. Postoperative outcomes and survival rates were comparable for both bioprostheses. Long-term follow-up is needed for comparisons with classical bioprosthesis models.

Numerical investigations of hybrid rocket engines

Paper presents the results of numerical studies of hybrid rocket engines operating cycle including unsteady-state transition stage. A mathematical model is developed accounting for the peculiarities of diffusion combustion of fuel in the flow of oxidant, which is composed of oxygen-nitrogen mixture. Three dimensional unsteady-state simulations of chemically reacting gas mixture above thermochemically destructing surface are performed. The results show that the diffusion combustion brings to strongly non-uniform fuel mass regression rate in the flow direction. Diffusive deceleration of chemical reaction brings to the decrease of fuel regression rate in the longitudinal direction.

Life history variation across latitudes: observations between capelin (Mallotus villosus) from Newfoundland and the eastern Canadian Arctic

Life history trait variation within a species promotes regional-specific strategies that optimize fitness in a particular environment. Capelin (Mallotus villosus) is an important forage fish species with a circumpolar, temperate distribution, but has increased in relative abundance in Arctic regions recently. To examine for region-specific life history strategies, we compared life history characteristics (length, body condition, age of sexual maturity and growth) of spawning male capelin collected from the eastern Canadian Arctic, in Pangnirtung Fjord, Nunavut (66°N; July 2014 and June–July 2015) with a sub-Arctic location on the northeast coast of Newfoundland (49°N; July 2014 and 2015). First year growth was higher for sub-Arctic relative to Arctic capelin. In contrast, body condition (regression of total length versus mass) was lower for capelin in the Arctic compared to the sub-Arctic population. The age structure of spawning males suggested that Newfoundland capelin reached sexual maturity earlier, as the youngest spawners in Newfoundland were age 2+ (median age: 3+) relative to Pangnirtung where the median spawning age was 4+ (maximum age 5+). Overall, Arctic capelin were generally characterized by lower growth, especially in the first year, later age of reproduction, and lower body condition, relative to the sub-Arctic population. These differences may be the result of limited gene flow on the northern margins of this species’ geographical distribution. They also support previously reported genetic distinction among the sub-Arctic and Arctic clades in the North Atlantic.

Association of Cardiovascular Responses in Mice with Source-apportioned PM2.5 Air Pollution in Beijing

ABSTRACT In this study, factor analysis and mass regression were used to identify four fine particulate matter sources and estimate their contributions to the ambient air pollution in Beijing. The identified sources were traffic re-suspended soil, mixed industrial sources, oil combustion, and secondary sulfate. The estimated source contributions were then introduced into two models as exposure variables to explore the relationships between cardiovascular responses in mice and PM exposures. We observed that PM2.5 has a small negative acute effect on heart rate, but the individual source factors showed much more significant effects. Traffic re-suspended soil had the most significant effect on heart rate, with a positive contribution on the day of exposure and a negative one on day lag 1. Acute heart rate variability outcomes were better explained by the total PM2.5 than by the source components. Chronic effects were observed as a decreased heart rate but an increased number of heart rate variability outcomes.

Impressive response and longterm survival in a patient with metastatic extraskeletal myxoid chondrosarcoma treated with radiotherapy and trabectedin: a synergistic activity

The extraskeletal myxoid chondrosarcoma (EMC) is a rare malignant accounting for less than 3% of soft tissue tumors. EMC is considered an intermediate aggressive neoplasm with a slow-growing and indolent clinical course. Nevertheless, local recurrence is frequent and distant metastases arise in about 50%-90% of cases. For these patients therapeutic options are scarce due to the poorly sensitivity of EMC to cytotoxic chemotherapy and targeted therapy. We report the case of a caucasian adult man with bulky locoregional and mediastinal disease resistant to antracyclinbased chemotherapy and targeted therapy. Then, a third line chemotherapy with trabectedin was used obtaining temporary disease stabilization. Due to arising of symptoms and modest increase of lesions, radiotherapy was added with four consecutive treatments on right gluteal mass, large right and left paravertebral lesions, and mediastinal bulky disease, respectively. Rapidly, near complete regression of masses was noted. After 41 months from metastasis and 28 after beginning of chemotherapy with trabectedin and complementary radiotherapy, the patient is in good clinical conditions and the disease under control. In our experience, radiotherapy is a valid option in metastatic ECM and when associated with trabectedin a potent synergistic effect could be obtained.

Invited Commentary

Invited Commentary

Thoracic Changes after Full Laser Ablation of the Feeding Artery in Fetuses with Bronchopulmonary Sequestration

Objective: To assess longitudinal intrathoracic changes after fetal laser surgery in fetuses with bronchopulmonary sequestration (BPS) with hydrops and/or hydrothorax. Study Design: The presence of intrafetal fluid effusions, the lung mass volume ratio (congenital pulmonary airway malformation volume ratio [CVR]), and the observed/expected lung-to-head circumference ratio (O/E-LHR) of both lungs were evaluated in a cohort of BPS fetuses with hydrops and/or hydrothorax treated with full laser ablation of the feeding artery (FLAFA). The longitudinal changes in intrafetal fluid effusions, lung mass volume, and pulmonary growth were analyzed by survival and multilevel analysis against days after FLAFA. Results: FLAFA was successfully performed in 15 cases at a median gestational age of 26.9 weeks. A complete disappearance of the hydrops and hydrothorax was observed a median interval of 7.5 and 21 days after the fetal intervention, respectively. A progressive decrease in the CVR and an increment in the size of both lungs were observed after FLAFA. The O/E-LHR of the lung contralateral and ipsilateral to the side of the BPS became normal on average 8 and 10 weeks after FLAFA, respectively. Conclusion: Fetal laser surgery with FLAFA promotes disappearance of all fetal fluid effusions, a lung mass regression sequence, and a normalization of pulmonary growth.