Change In Total Volume Research Articles

Long Duration Bed Rest Modifies Cardiovagal Baroreflex Control but not Baroreflex Control of Muscle Sympathetic Action Potential Activity in Humans

Our understanding of altered neuro-cardiovascular control following long-duration inactivity via head-down bed rest (HDBR) is incomplete. Here, we retrospectively analyzed two long-duration HDBR studies, including female (n=17; 32±5 years) and male (n=16; 29±7 years) cohorts, to determine whether HDBR 1) alters spontaneous cardiovagal baroreflex sensitivity (cBRS) similarly between males and females and 2) alters spontaneous baroreflex control of muscle sympathetic action potentials (AP) in males. Heart rate (HR; electrocardiogram) and arterial blood pressure (BP; finger-plethysmography) were continuously measured during 5-minutes of supine rest prior to and following 60-days bed rest in a -6° head-down position. Spontaneous cBRS was assessed by the relationship between R-R interval and systolic BP analyzed using the linear regression sequence method. Recordings of multi-unit muscle sympathetic nerve activity (peroneal microneurography) were obtained and a continuous wavelet transform detected APs which were grouped into AP clusters with similar morphology (n=10, all males). Baroreflex threshold for AP cluster discharge was assessed by linear regression analysis of the relationship between AP cluster discharge probability and diastolic BP. No change in resting HR (64±9 versus 66±9 /min, P=0.12) or mean BP (91.2±9.0 versus 90.6±9.2 mmHg, P=0.73) occurred after HDBR. Reductions in cBRS after HDBR (-4.1±9.4 ms/mmHg, Time effect: P<0.01) were similar between males and females (Time-by-Sex effect: P=0.51) and not related to changes in total blood volume (r2=0.045, P=0.24). Grouped AP clusters demonstrated heterogenous arterial baroreflex threshold gain according to AP cluster morphology (Cluster effect: P<0.01) which was unaltered following HDBR (Time-by-Cluster effect: P=0.43). In summary, males and females similarly attenuate cBRS following 60-days of HDBR and novel evidence indicates HDBR does not alter spontaneous baroreflex control of muscle sympathetic APs in males.

The Effectiveness of Diffusion Tensor Imaging in Determining Radiological Response after Radiosurgery in Patients with Vestibular Schwannoma.

The effectiveness of Diffusion Tensor Imaging (DTI) in demonstrating functional changes in the tumor in determining the response to treatment after radiosurgery in patients with vestibular schwannoma (VS) is not clear yet. The study aimed to determine the change in total tumor volume (TTV) in terms of radiological response in patients who had VS and were treated with radiosurgery and investigated the relationship between the TTV, follow-up times and DTI parameters. Thirty-one patients were assessed using DTI and MRI. TTV, apparent diffusion coefficient (ADC), and fractional anisotropy (FA) were calculated. Patients were divided into three groups: those who responded to the treatment (group 1) (n=11), those who did not (group 0) (n=9) and those who remained stable (group 2) (n=11). The mean duration of follow-up was 28.81±14 months. ADC values increased in patients with VS after radiosurgery (p=0.004). There was no statistical difference in the FA values. A significant reduction in TTV after radiosurgery was detected in group 1 (p=0.003). ADC values increased significantly after radiosurgery in group 2 (p=0.04). Although there were no significant differences, ADC values after radiosurgery increased in group 1 and group 0. ADC values continuously increase due to radiation damage in the period before the tumor volume shrinks after radiosurgery. We think that it is not appropriate to diagnose inadequate treatment or progression only when TTV is evaluated in terms of response to treatment in the early period after radiosurgery.

Mineral Dissolution and Precipitation Under Stress: Model Formulation and Application to Metamorphic Reactions

AbstractReactions in the Earth's crust occur through a dissolution‐precipitation process in the presence of fluid. Dissolution releases aqueous species which are transported to the locus of precipitation. This replacement process generates creep deformation (i.e., dissolution‐precipitation creep) due to volume change during reaction and stress‐controlled mass re‐distribution in the rock. Reaction under stress also modifies the rock microstructure and the pressure record during metamorphism. A quantitative model for dissolution‐precipitation creep is developed here by considering both dissolution and precipitation at grain interfaces to simulate replacement reactions under stress. A new creep law is obtained for pressure solution, allowing for the reaction‐ and the diffusion‐controlled cases to be modeled with a single expression. It is extended to replacement reactions by introducing volume change during reaction. Deformation mechanism maps are generated with the new creep law, indicating that, when fluid is present, dissolution‐precipitation creep is the dominant deformation mechanism in the Earth's crust. Numerical model reveals that grain shape preferred orientation only develops near thermodynamic equilibrium. This is consistent with measurements of porphyroblasts preferred orientation in rocks from the Nufenen Pass (Switzerland) having experienced prograde metamorphism. Kinetics play a key role on the thermodynamic pressure of metamorphic reaction. Near the equilibrium, reaction is controlled by either σ1 or σ3 depending on the total volume change during reaction whereas it is controlled by the mean stress far from the equilibrium.

Three-dimensional ultrasound imaging: An effective method to detect the effect of moderate intensity statin treatment in slowing carotid plaque progression.

We aimed to evaluate the feasibility of three-dimensional ultrasound imaging (3DUS) in assessing the therapeutic effect of moderate-intensity statin therapy on carotid atherosclerotic plaques. Patients with carotid plaques were recruited to the study from January 2016 to September 2018, and were divided into two groups based on whether or not they were taking statins. All participants underwent 3DUS of their carotid plaques at baseline, then 3months and 2 years after initial examination. The changes of the carotid plaques were compared between the two groups. Were included 97 patients (57 males and 40 females), 65.26 ± 9.53 year-old with 67 into the statin group and 30 in the control group. The baseline levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were lower in the statin group than in the control group (3.79 ± 0.78 mmol/L vs 4.50 ± 1.12 mmol/L; 2.01 ± 0.62 mmol/L vs 2.58 ± 0.91 mmol/L, P< .05). There was no significant difference in the change of total plaque volume (TPV) detected by 3D-US between the statin (median [interquartile range]: 0 [-30-20] mm3 ) and the control group (0 [-22.5-25] mm3 ) at 3months. Over 2 years, the TPV increased faster in the control group (+70 [25-150] mm3 ), than in the statin group (15 [-57.5-90) mm3 , P< .05). 3DUS can be an effective tool to observe the development of carotid plaques and the effect of statin treatment.

Intrinsic material constants of poroelasticity

Biot and Willis (1957) performed micromechanical analysis on isotropic poroelastic materials and presented three material constants, the jacketed compressibility, the unjacketed compressibility, and the coefficient of fluid content, to characterize the volumetric deformation. Brown and Korringa (1975) and Rice and Cleary (1976) recast them into a drained bulk modulus K, an unjacketed bulk modulus Ks′, and an unjacketed pore modulus Ks′′. The constant Ks′′ is tied to the storage capacity of porous medium; hence is highly important in petroleum and geosequestration applications. It is, however, difficult to measure in the laboratory due to the lack of a direct way to observe pore volume deformation.In this work, a physics based approach is used to explore these micromechanical constants. Three intrinsic material constants that isolate the physical mechanisms, an unjacketed solid bulk modulus Ks, a drained pore modulus Kp, and a micro inhomogeneity and anisotropy modulus Kψ, are presented to characterize the porous material. Bounds on material constants are developed based on thermodynamics and elastic stability requirements. Past attempts in measuring Ks′′ using direct or indirect approaches are compiled. Most of the efforts failed to satisfy the theoretical bounds. Only those attempted to measure the change in pore volume passed the test. The intrinsic constants are used to interpret the bulk material constants, such as the drained and undrained bulk modulus, and the storage and Skempton pore pressure coefficient. The total volume change and the storage capacity can be partitioned into those attributed to solid, pore, fluid, and the microinhomogeneity compressibilities. A published data set on stress dependent Skempton pore pressure coefficient and bulk modulus is reanalyzed. The data are matched by the calibration of a single of Kψ value.

Metabolic profiling in children and young adults with autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is the most commonly inherited kidney disease. Although children with ADPKD show normal renal function, cyst development is already occurring. In this study, we aimed to identify markers and associated molecular pathways of disease progression in children and young adults with ADPKD. Plasma samples were collected during a 3-year randomized, double-blind, placebo-controlled, phase III clinical trial that was designed to test the efficacy of pravastatin on slowing down ADPKD progression in pediatric patients. Samples from 58 patients were available at baseline and at the 3-year endpoint of the study, respectively. Furthermore, plasma samples from 98 healthy children were used as controls. Metabolomic analysis was performed using liquid chromatography-tandem mass spectrometry and differences in metabolic profiles over time and within study groups were evaluated. While pravastatin therapy led to a decrease in a percent change of total kidney volume (HtTKV) in ADPKD patients, it had minimal effects on metabolite changes. Oxidative stress, endothelial dysfunction, inflammation and immune response were the most affected signaling pathways that distinguished healthy from diseased children. Pathway analysis revealed that metabolites in the arginine metabolism (urea and nitric oxide cycles), asparagine and glutamine metabolism, in the methylation cycle and kynurenine pathway were significantly changed between healthy and children with ADPDK and continued to diverge from the control levels while the disease progressed. Detected metabolite changes were primarily governed by disease progression, and less by pravastatin treatment. Identified metabolic pathways, from arginine and asparagine to kynurenine metabolism could present therapeutic targets and should be further investigated for potential to treat ADPKD progression at an early stage.

The Effect of Disease Type on Changes in Total Lung Volume after Lung Transplantation Measured by Three-Dimensional (3D) CT Reconstruction

<h3>Purpose</h3> It is accepted that a donor's predicted total lung capacity (pTLC) can be 75-125% of the recipient's pTLC in lung transplantation; however, ‘optimal graft size' is not clearly defined, especially in restricted lung disease (RD) patients. These disagreements exist as it is difficult to accurately measure lung size before and after transplantation and it is also difficult to predict and evaluate the extent of re-expansion of the restricted thoracic cavity after transplantation. This study examined changes in lung volume after lung transplantation using a 3D lung volume measurement from CT scans before and after surgery under the assumption that the patient's thoracic cavity would return to the size of the patient without underlying lung disease after surgery. <h3>Methods</h3> A total of 113 patients, who underwent lung transplantation between September 2012 and April 2019 in our institute, and met the inclusion criteria were enrolled in the study. This included 88 patients who were diagnosed with RD and 25 patients who were diagnosed with non-RD. Patients were further divided into oversized and undersized groups according to the donor and recipient pTLC ratio, and a total of 4 groups were studied. Preoperative and postoperative lung volume on CT scans were measured using the synapse 3D program (Fuji film, Japan). <h3>Results</h3> RD patients showed a significant increase in total lung volume (TLV) after surgery, while non-RD patients showed a decrease in TLV. These changes showed the greatest increase in the RD group within 1 year and continuously increased up to 5 years. In the non-RD group, TLV decreased within 3 months of surgery. These changes were not related to graft size. <h3>Conclusion</h3> In lung transplant patients, the thoracic cavity re-expanded in RD patients and reduced in the non-RD patients, returning to healthy values without lung disease status in terms of TLV.

Effects of chronic kidney disease and declining renal function on coronary atherosclerotic plaque progression: a PARADIGM substudy

To investigate the change in atherosclerotic plaque volume in patients with chronic kidney disease (CKD) and declining renal function, using coronary computed tomography angiography (CCTA). In total, 891 participants with analysable serial CCTA and available glomerular filtration rate (GFR, derived using Cockcroft-Gault formulae) at baseline (CCTA 1) and follow-up (CCTA 2) were included. CKD was defined as GFR <60 mL/min/1.73 m2. Declining renal function was defined as ≥10% drop in GFR from the baseline. Quantitative assessment of plaque volume and composition were performed on both scans. There were 203 participants with CKD and 688 without CKD. CKD was associated with higher baseline total plaque volume, but similar plaque progression, measured by crude (57.5 ± 3.4 vs. 65.9 ± 7.7 mm3/year, P = 0.28) or annualized (17.3 ± 1.0 vs. 19.9 ± 2.0 mm3/year, P = 0.25) change in total plaque volume. There were 709 participants with stable GFR and 182 with declining GFR. Declining renal function was independently associated with plaque progression, with higher crude (54.1 ± 3.2 vs. 80.2 ± 9.0 mm3/year, P < 0.01) or annualized (16.4 ± 0.9 vs. 23.9 ± 2.6 mm3/year, P < 0.01) increase in total plaque volume. In CKD, plaque progression was driven by calcified plaques whereas in patients with declining renal function, it was driven by non-calcified plaques. Decline in renal function was associated with more rapid plaque progression, whereas the presence of CKD was not.

Total Volume Change Measurement of Unsaturated Soil in Triaxial Tests: A New Approach

Abstract In the evaluation of unsaturated soil behavior in the laboratory, it is required to measure the total volume change of triaxial soil specimens. This, however, is not an easy task, with setups proposed in the literature being quite expensive or presenting variable setbacks. In this context, this article presents a new, reliable, cheap system to estimate the total volume change of the soil in unsaturated conditions in triaxial tests. To do so, a double-chamber triaxial cell was developed, with the inner cell connected to an air-tight container subjected to the same cell pressure and positioned on a precision analytical scale. The measure of the total volume change is given by the mass of water entering or leaving the air-tight container. After calibration, the system was tested under consolidation using saturated soil samples. Comparing the conventional change in water volume of the saturated specimen with the variation of the total volume obtained through the developed system, a maximum difference of 0.01 cm3 is obtained, which equals only 0.01 % of the specimen volume. The effects of temperature and of cell pressure variation, which might occur during the saturation of unsaturated specimens in conventional triaxial tests, are also presented and discussed.

Abstract 40: Hematoma Expansion Shift Analysis to Assess Acute Intracerebral Hemorrhage Treatments

Background and Purpose: In present-day intracerebral hemorrhage (ICH) trials, hematoma expansion (HE) is often analyzed as a binary variable - present or absent. However, dichotomizing intrinsically wide-ranging variables discards substantial information reflective of treatment effect and can reduce the ability to detect relationships between the exposure and outcome of interest. We explored the concept of a “HE shift analysis” as a novel analytic mode for ICH treatment trials using previously published clinical trial data. Methods: Using data from the Antihypertensive Treatment of Acute Cerebral Hemorrhage II (ATACH-2) trial, patients were stratified by treatment status (intensive vs. standard blood pressure lowering with IV nicardipine) and HE shift was evaluated by generating strata based on a) previously established HE definitions, b) quartiles of 24-hour total hematoma volume, and c) quartiles of 24-hour total hematoma volume (THV) change. The relationship between blood pressure treatment and hematoma expansion shift was explored using proportional odds models and adjusted Wilcoxon testing. Results: The primary analysis population included 863 patients. In both treatment groups, approximately one-third of patients exhibited no hematoma growth. Using a conventional threshold, significant intraparenchymal expansion (≥33%) was reduced by 5.8% in those assigned to the intensive therapy arm (aOR: 0.77 [95% CI: 0.60-0.99], Figure 1A). The stratified quartiles of 24-hour total hematoma volumes were associated with a 5% shift within the highest and lowest strata in the intensive arm, (aOR: 0.83 [0.66-1.05], Figure 1B). Intensive therapy was associated with a 5.2% reduction from &gt; 3 mL to 0.5-3 mL (aOR: 0.86 [0.68-1.09], Figure 1C). Conclusions: A shift analysis model of HE provides additional insights into the biological effects of a given therapy and may be an alternate way to assess hemostatic agents in future hemorrhage trials.

Abstract P370: Early Brain Volume Change After Stroke: Subgroup Analysis From the Axis-2 Trial

Objective: The timing of brain atrophy after stroke is not well understood. We investigated the associations between age and imaging features and brain volume change in the first month after stroke. Methods: We retrospectively studied patients with acute ischemic stroke enrolled in the AXIS-2 trial. Total brain volume change from hyperacute MRI data to the first month after stroke was assessed using unified segmentation in SPM12. We hypothesized that age, ischemic brain lesion size and white matter changes were associated with larger brain volume change. Enlarged perivascular spaces (EPVS) and white matter hyperintensities (WMH) were rated visually and the presence of lacunes was assessed. Results: We enrolled 173 patients with a mean age of 67±11 years, 44 % were female. There was a median 6 mL decrease in volume (25th percentile -1mL-75th percentile 21mL) over time, equivalent to a median 0.5% (IQR-0.07% - 1.4%), decrease in brain volume. Age was associated with larger brain volume loss (per 10 years of age, 5 mL 95% CI 2 mL-8 mL). Baseline DWI lesion volume was not associated with greater volume loss (per 10 mL of lesion volume, change by 0 mL (95% CI -0.1 mL-0.1mL). Increasing Fazekas scores of deep white matter hyperintensity were associated with greater tissue loss (5 mL, 95% CI 1 mL-10 mL). Brain volume change was associated with ordinal change on the modified Rankin scale at 90 days (per 10 ml, OR 1.085, 95% CI 1.031-1.141) but the association was not present when adjusting for age, baseline diffusion lesion volume and NIHSS score (OR 1.044, 95% CI 0.990-1.010).Interpretation-Global brain volume loss occurs over 1 month after stroke and is associated with age and deep white matter disease. We did not find evidence that more severe strokes lead to increased early tissue loss.

An Integrated Simulation Approach To Predict Permeability Impairment under Simultaneous Aggregation and Deposition of Asphaltene Particles

Summary Formation damage mechanisms in general lower the quality of the near wellbore, often manifested in the form of permeability reduction, and thus reducing the productivity of production wells and injectivity of injection wells. Asphaltene deposition, as one of the important causes, can trigger serious formation damage issues and significantly restrict the production capacity of oil wells. Several mechanisms acting simultaneously contribute to the complexity associated with prediction of permeability impairment owing to asphaltene deposition; thus, integration of modeling efforts for asphaltene aggregation and deposition mechanisms seems inevitable for improved predictability. In this work, an integrated simulation approach is proposed to predict permeability impairment in porous medium. The proposed approach is novel because it integrates various mathematical models to study permeability impairment considering porosity reduction, particle aggregation, and pore connectivity loss caused by asphaltene deposition. To improve the accuracy of simulation results, porous media is considered as a bundle (different size) of capillary tubes with dynamic interconnectivity. The total volume change of interconnected tubes will directly represent permeability reduction realized in porous media. The prediction of asphaltene deposition in porous media is improved in this paper via integration of the particle aggregation model into calculation. The simulation results were verified by comparing with existing experimental data sets. After that, a sensitivity analysis was performed to study parameters that affect permeability impairment. The simulation results show that our permeability impairment model—considering asphaltene deposition, aggregation, and pore connectivity loss—can accurately reproduce the experimental results with fewer fitting or empirical parameters needed. The sensitivity analysis shows that longer aggregation time, higher flow velocity, and bigger precipitation concentration will lead to a faster permeability reduction. The findings of this study can help provide better understanding of the permeability impairment caused by asphaltene deposition and pore blockage, which provides useful insights for prediction of production performance of oil wells.

Temporal changes in total and hippocampal brain volume and cognitive function in patients with chronic heart failure-the COGNITION.MATTERS-HF cohort study.

AimsWe quantified the concurring dynamics affecting total and hippocampal brain volume and cognitive function in patients with chronic heart failure (HF) over a period of three years.Methods and resultsA total of 148 patients with mild stable HF entered this monocentric prospective cohort study: mean age 64.5 (10.8) years; 16.2% female; 77% in New York Heart Association functional classes I–II; 128 and 105 patients attended follow-up visits after 1 and 3 years, respectively. The assessment included cardiological, neurological, psychological work-up, and brain magnetic resonance imaging. Total and regional brain volumes were quantified using an operator-independent fully automated approach and reported normalized to the mean estimated intracranial volume. At baseline, the mean hippocampal volume was ∼13% lower than expected. However, the 3-year progressive hippocampal volume loss was small: −62 mm3 [95% confidence interval (CI) −81 to −42, P < 0.0001). This corresponded to a relative change of −1.8% (95% CI −2.3 to −1.2), which was similar in magnitude as observed with physiological aging. Moreover, the load of white matter hypointensities increased within the limits of normal aging. Cognitive function during the 3-year observation period remained stable, with ‘intensity of attention’ as the only domain declining (LSmean −1.82 points, 95% CI −3.05 to −0.58, P = 0.004). After 3 years, performance in all domains of cognition remained associated with hippocampal volume (r ≥ 0.29).ConclusionIn patients with predominantly mild HF, the markedly reduced hippocampal volume observed at baseline was associated with impaired cognitive function, but no accelerated deterioration in cognition and brain atrophy became evident over a mid-term period of three years.

Genetic identification of inherited cystic kidney diseases for implementing precision medicine: a study protocol for a 3-year prospective multicenter cohort study

BackgroundInherited cystic kidney disease is a spectrum of disorders in which clusters of renal cysts develop as the result of genetic mutation. The exact methods and pipelines for defining genetic mutations of inherited cystic kidney disease are not clear at this point. This 3-year, prospective, multicenter, cohort study was designed to set up a cohort of Korean patients with inherited cystic kidney disease, establish a customized genetic analysis pipeline for each disease subtype, and identify modifying genes associated with the severity of the disease phenotype.Methods/designFrom May 2020 to May 2022, we aim to recruit 800 patients and their family members to identify pathogenic mutations. Patients with more than 3 renal cysts in both kidneys are eligible to be enrolled. Cases of simple renal cysts and acquired cystic kidney disease that involve cyst formation as the result of renal failure will be excluded from this study. Demographic, laboratory, and imaging data as well as family pedigree will be collected at baseline. Renal function and changes in total kidney volume will be monitored during the follow-up period. Genetic identification of each case of inherited cystic kidney disease will be performed using a targeted gene panel of cystogenesis-related genes, whole exome sequencing (WES) and/or family segregation studies. Genotype-phenotype correlation analysis will be performed to elucidate the genetic effect on the severity of the disease phenotype.DiscussionThis is the first nationwide cohort study on patients with inherited cystic kidney disease in Korea. We will build a multicenter cohort to describe the clinical characteristics of Korean patients with inherited cystic kidney disease, elucidate the genotype of each disease, and demonstrate the genetic effects on the severity of the disease phenotype.Trial registrationThis cohort study was retrospectively registered at the Clinical Research Information Service (KCT0005580) operated by the Korean Center for Disease Control and Prevention on November 5th, 2020.

Undrained Seismic Compression of Unsaturated Sand

Unsaturated soils in engineered geostructures like embankments or retaining walls may experience seismic compression during earthquakes due to particle rearrangement associated with large-strain cyclic shearing. Although previous studies have investigated volume changes during drained cyclic shearing of unsaturated soils, undrained cyclic shearing presents a more complex situation. During undrained cyclic shearing, changes in total volume, matric suction, degree of saturation, effective stress, shear modulus, and damping ratio may occur that have complex coupling effects that affect seismic compression. To better understand these coupling effects, this study performed a series of undrained cyclic simple shear tests on unsaturated sand specimens. Contractile volumetric strain after 200 cycles in these tests was found to vary nonlinearly with degree of saturation. The largest volumetric contraction occurred at a degree of saturation of 0.4 and coincided with the largest decrease in mean effective stress. The sand specimens followed a wetting-path scanning curve during shearing, with small changes in matric suction. The decrease in mean effective stress during cyclic shearing for all specimens followed the same linear relation with the accumulation of volumetric strain.

Effects of cerebral hypoperfusion on the cerebral white matter: a meta‑analysis.

Decreased cerebral blood flow (CBF) in aging is known to induce aging‑related cerebral deteriorations, such as neuronal degeneration, white matter (WM) alterations, and vascular deformations. However, the effects of cerebral hypoperfusion on WM alterations remain unclear. This study investigates the relationship between cerebral hypoperfusion and WM total volume changes by assessing the trends in CBF and WM changes by meta‑analysis. In this meta‑analysis, the differences in CBF were compared according to cerebral hypoperfusion type and the effect of cerebral hypoperfusion on the total volume of WM changes in rodents. Using subgroup analysis, 13 studies were evaluated for comparing CBF according to the type of cerebral hypoperfusion; 12 studies were evaluated for comparing the effects of cerebral hypoperfusion on the total volume of WM changes. Our meta‑analysis shows that the total volume of WM decreases with a decrease in CBF. However, the reduction in\r\nthe total volume of WM was greater in normal aging mice than in the cerebral hypoperfusion model mice. These results suggest that the reduction of cerebral WM volume during the aging process is affected by other factors in addition to a decrease in CBF.

Comparing Outcomes of Airway Changes and Risk of Sleep Apnea after Bimaxillary Orthognathic Surgery and Mandibular Setback Surgery in Patients with Skeletal Class III Malocclusion: A Systematic Review and Meta-Analysis

Objective: To compare the airway changes and risks of sleep apnea after the bimaxillary orthognathic surgery and mandibular setback surgery in the growing patients with skeletal Class III malocclusion . Material and Methods: MEDLINE, PubMed, Cochrane Library, Embase, ISI, Google scholar have been utilized as the electronic databases for performing systematic literature between 2010 to August 2020. The quality of the included studies has been assessed using MINORS. Meta-analysis was performed using Stata 16 software. Results: In electronic searches, a total of 218 potentially relevant abstracts and topics have been found. Finally, 23 papers met the criteria defined for inclusion in this systematic review. The mean difference of upper airway total volume changes between before and after surgery was (MD = 1.86 cm 3 95% CI 0.61 cm 3 -3.11 cm 3 ; p= 0.00) among 14 studies. This result showed that after Mandibular Setback Surgery, there was a statistically significant decrease in the upper airway volume . Conclusion: Class III Patients who undergo bimaxillary surgery show no other significant difference in airways volume after surgery than patients in Class III who undergo mandibular setback alone.

An Efficient Statistical Approach to Develop Intensity-Duration-Frequency Curves for Precipitation and Runoff under Future Climate.

Ongoing and potential future changes in precipitation will affect water management infrastructure. Urban drainage systems are particularly vulnerable. Design standards for many stormwater practices rely on precipitation intensity-duration-frequency (IDF) curves based on extreme value analysis. General Circulation Models (GCMs) project increases in future average temperature but are less clear on changes in precipitation. In many areas, climate projections suggest relatively small changes in total precipitation volume, but also suggest increased magnitude of extreme events. Model skill in predicting extreme precipitation events, however, is limited. We develop an approach for estimating future IDF curves that is efficient, uses widely available statistically downscaled GCM output, and is consistent with published IDF curves for the United States that are often incorporated into local stormwater regulations and design guides (and are GCM model agnostic). The method provides a relatively simple way to develop scenarios in a format directly useful to assessing risk to stormwater management infrastructure. Model biases are addressed through equidistant quantile mapping, in which the modeled change in the cumulative distribution of storm events from historical to future conditions is used to adjust the extreme value fit used for IDF curve development. The approach is efficient because it requires only annual maxima and is readily automated, allowing rapid examination of results across projections. We estimate future IDF curves at locations throughout the United States and link IDF-derived design storms to a rainfall-runoff model to evaluate the potential change in storage volume requirements for capture-based stormwater management practices by 2065.

Effects of pursed-lip breathing and forward trunk lean postures on total and compartmental lung volumes and ventilation in patients with mild to moderate chronic obstructive pulmonary disease

This study identified the effects of pursed-lip breathing (PLB), forward trunk lean posture (FTLP), and combined PLB and FTLP on total and compartmental lung volumes, and ventilation in patients with chronic obstructive pulmonary disease (COPD). Sixteen patients with mild to moderate COPD performed 2 breathing patterns of quiet breathing (QB) and PLB during FTLP and upright posture (UP). The total and compartmental lung volumes and ventilation of these 4 tasks (QB-UP, PLB-UP, QB-FTLP, PLB-FTLP) were evaluated using optoelectronic plethysmography. Two-way repeated measures ANOVA was used to identify the effect of PLB, FTLP, and combined strategies on total and compartmental lung volumes and ventilation. End-expiratory lung volume of ribcage compartment was significantly lower in PLB-UP than QB-UP and those with FTLP (P < .05). End-inspiratory lung volume (EILV) and end-inspiratory lung volume of ribcage compartment were significantly greater during PLB-FTLP and PLB-UP than those of QB (P < .05). PLB significantly and positively changed end-expiratory lung volume of abdominal compartment (EELVAB ) end-expiratory lung volume, EILVAB, tidal volume of pulmonary ribcage, tidal volume of abdomen, and ventilation than QB (P < .05). UP significantly increased tidal volume of pulmonary ribcage, tidal volume of abdomen, and ventilation and decreased EELVAB, end-expiratory lung volume, and EILVAB than FTLP (P < .05). In conclusion, combined PLB with UP or FTLP demonstrates a positive change in total and compartmental lung volumes in patients with mild to moderate COPD.

Long-term effects of mini-screw-assisted rapid palatal expansion on airway.

To evaluate the long-term effects on airway in patients with mini-screw-assisted rapid palatal expansion (MARPE), rapid palatal expansion (RPE), and controls with three-dimensional cone-beam computed tomography (CBCT) analysis. A total of 180 CBCTs of 60 patients were analyzed at different time points, such as pretreatment, postexpansion, and posttreatment. Patients were divided into three groups: mini-screw assisted rapid palatal expansion (MARPE), rapid palatal expansion (RPE), and controls. The nasal cavity, nasopharyngeal, oropharyngeal, and laryngopharyngeal airway volume and area were measured. Changes in total airway volume, total airway area, minimal cross-sectional area, maxillary intermolar width, external maxillary width, and palatal width were also evaluated. Both MARPE and RPE caused a statistically significant increase in the airway after expansion as compared with the control group, but there was no statistically significant difference in the change in airway between MARPE, RPE, and the control group at posttreatment, except for nasopharyngeal volume, which was significantly increased in the MARPE group. There was no correlation between the amount of expansion and increase in total airway volume. There was a significant increase in total airway volume, total airway area, and minimal cross-sectional area with MARPE and RPE immediately after expansion, but at posttreatment, the changes in the MARPE and RPE groups were similar to the change in the control group. However, MARPE led to a significant long-term increase in nasopharyngeal volume. The amount of expansion did not correlate with the increase in pharyngeal airway volume.