Higher Relative Improvement Research Articles

The effect of high-intensity focused electromagnetic procedure on visceral adipose tissue: Retrospective assessment of computed tomography scans.

BackgroundHigh levels of visceral adipose tissue (VAT) are associated with abdominal obesity and increased risk of metabolic deterioration. Recent studies showed that intensive physical exercise results in the reduction of subcutaneous and visceral fat.AimsThis study investigates the effect of supramaximal muscle contractions induced by a HIFEM procedure for abdominal VAT changes.MethodsComputed tomography (CT) scans of 22 subjects (47.3 ± 8.4 years, BMI of 23.5 ± 3.5 kg/m2) who received 8 HIFEM treatments of the abdomen (2‐3 days apart) were retrospectively evaluated for the changes in VAT. The CT scans were obtained at baseline and 1 month after the last treatment. The transverse slices at umbilical, infraumbilical, and supraumbilical levels were used to determine the cross‐sectional area (CSA) of VAT through a semi‐automated segmentation method.ResultsAnalysis of the CSA revealed a significant (P = .004) and uniform reduction of the abdominal VAT area by 14.3% (−16.7 cm2) from 110.6 ± 69.0 cm2 to 93.9 ± 54.6 cm2. In general, a higher relative improvement was seen infraumbilically (17.1%), followed by supraumbilical (15.5%) and umbilical (10.7%) levels. The reduction of VAT was strongly correlated to the reduction of subcutaneous fat (r(17) = 0.66; P = .002). A decrease in VAT volume contributed to the overall aesthetic enhancement visible on digital photographs.ConclusionsThe outcomes indicate that HIFEM technology has a positive effect on VAT. However, further studies are necessary to validate these outcomes and to clarify the exact mechanism of a VAT reduction. Based on our results, the HIFEM procedure may be a beneficial treatment option for patients with high VAT deposits.

Modified differential evolution and heuristic algorithms for dump tippler machine allocation in a typical sugar mill in Thailand

This paper focuses on a computational tool for scheduling and sequencing sugarcane vehicles for dump tippler machines at the mill yard of a sugar mill, which can be represented as an NP-hard problem for parallel capacitated machines with machine restrictions, job grouping, and sequencing independent setup time. This research aims to determine the optimal sequencing of jobs, i.e. minimizing the makespan by considering machine restrictions, capacitated machines, group size, number of jobs, and the constraints of the sugar mill. In the considered problem machines alternatively operate, that distinguishes it from a general parallel machine problem. The mixed integer linear programing model is developed for solving the small-scale problem instances. Large-scale instances are handled by four heuristics, and four differential evolution (DE) metaheuristics. In order to improve the computational results, solution quality and computation time were considered. In addition, modified DE algorithms were used in encoding operation (initial solution), mutation and local search operation. The computational results revealed that the modified DE algorithms had higher relative improvement on the makespan. Furthermore, this decision-making support tool was implemented as a prototype in the sector of cane and sugar industry in Thailand and extended to other similar industries.

An experimental investigation and fractal modeling on the effective thermal conductivity of novel autoclaved aerated concrete (AAC)-based composites with silica aerogels (SA)

Abstract Improving the thermal insulating performance of porous building material is of great practical significance for energy-efficient buildings. In this work, silica aerogels (SA) having ultralow thermal conductivity were incorporated into autoclaved aerated concrete (AAC) via physical solution impregnation method to further improving its thermal insulating performance. As expected, the addition of SA lowers the thermal conductivity of the composites and the improvement in thermal insulating performance depends on porosity of the pristine AAC. At the SA loading of ~7 wt.%, the highest relative improvement was found to be nearly 30%. Two types of fractal models, i.e., parallel and serial, were established to predict the thermal conductivity of the SA-AAC composites. It was observed that the serial model could match well with the experiment data of the AAC-300 and AAC-400-based composites. A hybrid model of the two types was proposed so as to predict the data for the composites more satisfactorily. This modeling effort helped us better understand the role of the impregnated SA on the heat conduction mechanisms in the composites. As an extra bonus, the compressive strength and the capillary water absorption coefficient of the composites were found to increase and decrease slightly, respectively, with increasing the SA content. The lower water absorptivity indicates a better potential durability. The results shed light on the great potential of such composites in real-world applications if the cost issue can be addressed by future advances in materials fabrication technologies.

The Potential Benefits of Deferred Payment for a Hypothetical Gene Therapy for Congestive Heart Failure: A Cost-Consequence Analysis.

The emergence of potentially curative pharmacologic treatments that deliver long-term clinical benefits with a limited number of doses may create short-term budget challenges for payers as their unit price can be high. This paper tests the clinical and financial properties of a deferred payment model (DPM) in hypothetical therapy for congestive heart failure (CHF) from the perspective of payers, manufacturers, and patients. We present an empirical analysis of longitudinal data for cardiovascular admissions and mortality using a Markov transition model for patient progression under different payment scenarios. The model calculates life-years gained and avoided cardiovascular admissions under the status quo and deferred payment and a hypothetical budget constraint. We tracked over 91,000 Medicare fee-for-service beneficiaries over a period of 5years (2009-2014) using MedPAR 5% data files. We find that a DPM is associated with earlier treatment and a consequent improvement in clinical outcomes. A 25% down-payment is associated with the highest relative improvement and reduces hospital admissions by 0.52% (by 2611 vs. 2071 cases) and mortality by 0.29% (by 799 vs. 648 cases), both relative to the status quo payment. Deferred payment results in limited financial gains for payers or manufacturers, primarily because of the small share of expected cost savings on the total cost of therapy. Our results are robust to changes in relative risk for cardiovascular admissions and a change in the cost of therapy. A DPM may result in faster access to CHF gene therapy and may thus reduce hospital admissions and mortality in contrast to a status quo payment with the same budget constraint. Although the financial benefits of a DPM in CHF gene therapy are limited, it is possible that deferred payments will show greater promise for treatments with higher cost offsets.

Thermal Conductivity of Silica-aerogel (SA) and Autoclave Aerated Concrete (AAC) Composites

Improving the thermal insulating performance of porous building materials is of great practical significance for building energy conservation. In this work, silica aerogels (SA) with ultralow thermal conductivity were proposed as an appropriate candidate to be integrated with autoclaved aerated concrete (AAC) to produce novel SA-AAC composites with higher thermal insulating performance by physical solution impregnation method. The pore-structures, mechanical and thermal properties of the SA-AAC composites were probed by various experimental tests. According to the microscopy and porosimetry results, SA were observed to adhere to the surface walls of the AAC holes, thus reducing the amount of macro-sized pores. In addition, the improved thermal insulating performance of AAC was successfully achieved with the relative improvement depending on the porosity of the pristine AAC. At the mass fraction of SA of ~7%, the highest relative improvement was found to be ~30% The results of this work exhibited a great potential of this novel SA-AAC composite in engineering applications.

Quantification of carbon nanotube dispersion and its correlation with mechanical and thermal properties of epoxy nanocomposites

ABSTRACTAn experimental study is carried out to quantitatively assess the dispersion quality of carbon nanotubes (CNTs) in epoxy matrix as a function of CNT variant and weight fraction. To this end, two weight fractions (0.05% and 0.25%) of as‐grown, oxidized, and functionalized CNTs are used to process CNT/epoxy nanocomposites. Scanning electron microscopy, X‐ray diffraction, and Fourier transform infrared analysis of different variants of CNTs are used to establish the efficiency of purification route. While the relative change in mechanical properties is investigated through tensile and micro‐hardness testing, thermal conductivity of different nanocomposites is measured to characterize the effect of CNT addition on the average thermal properties of epoxy. Later on, a quantitative analysis is carried out to establish the relationship between the observed improvements in average composite properties with the dispersion quality of CNTs in epoxy. It is shown that carboxylic (‐COOH) functionalization reduces the average CNT agglomerate size and thus ensures better dispersion of CNTs in epoxy even at higher CNT weight fraction. The improved dispersion leads to enhanced interfacial interaction at the CNT/epoxy interface and hence provides higher relative improvement in nanocomposite properties compared to the samples prepared using as‐grown and oxidized CNTs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48879.

Poly(vinyl alcohol) foams reinforced with carbon nanotubes for stapedial annular ligament applications

ABSTRACTThis study aims to develop carbon nanotubes (CNTs) reinforced poly(vinyl alcohol) (PVA) foams as a possible material for stapedial annular ligament (SAL) application. As‐grown (AG) and purified CNTs are used as reinforcing fillers for PVA foams. Uniaxial and cyclic compression tests reveal that specific modulus and energy dissipation behavior improve after reinforcing foam with CNTs. A relatively higher improvement in specific modulus is recorded for purified CNTs as they tend to produce stiffer cell walls. Thermogravimetric analysis shows thermal stability improves after addition of CNTs in PVA foams. The 50 wt % degradation temperature is higher for PVA_AG foam in comparison to neat PVA foam. Under dynamic loading storage, modulus is found to be higher for CNT doped foams with higher relative improvement with purified CNTs than AG CNTs. It is shown that reinforcing PVA foams with purified CNTs is a feasible strategy to improve their average mechanical properties and microstructure for SAL application. While the specific elastic modulus of neat PVA foam found to be in range of 0.05–0.06 MPa gcc−1 with almost zero porosity. The addition of CNTs provides a wide range of specific elastic modulus 0.1–1.3 MPa gcc−1 with an average pores size of about 300 μm. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48736.

Mapping Soil Electrical Conductivity Using Ordinary Kriging Combined with Back-propagation Network

Accurate mapping of soil salinity and recognition of its influencing factors are essential for sustainable crop production and soil health. Although the influencing factors have been used to improve the mapping accuracy of soil salinity, few studies have considered both aspects of spatial variation caused by the influencing factors and spatial autocorrelations for mapping. The objective of this study was to demonstrate that the ordinary kriging combined with back-propagation network (OK_BP), considering the two aspects of spatial variation, which can benefit the improvement of the mapping accuracy of soil salinity. To test the effectiveness of this approach, 70 sites were sampled at two depths (0–30 and 30–50 cm) in Ningxia Hui Autonomous Region, China. Ordinary kriging (OK), back-propagation network (BP) and regression kriging (RK) were used in comparison analysis; the root mean square error (RMSE), relative improvement (RI) and the decrease in estimation imprecision (DIP) were used to judge the mapping quality. Results showed that OK_BP avoided the both underestimation and overestimation of the higher and lower values of interpolation surfaces. OK_BP revealed more details of the spatial variation responding to influencing factors, and provided more flexibility for incorporating various correlated factors in the mapping. Moreover, OK_BP obtained better results with respect to the reference methods (i.e., OK, BP, and RK) in terms of the lowest RMSE, the highest RI and DIP. Thus, it is concluded that OK_BP is an effective method for mapping soil salinity with a high accuracy.

Effects of Microwave Pretreatment on Mesophilic Anaerobic Digestion for Mixture of Primary and Secondary Sludges Compared with Thermal Pretreatment

This work experimentally determined the effect of thermal and microwave pretreatments on the anaerobic digestion of mixtures of municipal primary and secondary sludges in semi-continuous mesophilic digesters at hydraulic retention times (HRT) of 20, 15, 10, 7, and 5 days. The ratio of soluble chemical oxygen demand (COD) to total COD in thermally pretreated and microwaved sludges at 80°C was 2.7 and 3.2 times higher than that of raw sludge, respectively. The volatile solids (VS) and COD removal efficiencies in all three di gesters fed with raw (control), thermally pretreated (TM), and microwaved (MW) sludges decreased as the HRT was reduced. The highest relative improvement in VS removal compared to the control occurred at the HRT of 5 days in the TM and MW (29 and 41% higher than the control, respectively). At this HRT, improvement in the COD removal efficiencies in the TM and MW compared to the control was 28 and 53%, respectively. Improvements in biogas production compared with the control increased in both the TM and MW as the HRT was reduced to 5 days. The relative improvement in daily biogas production compared to the control from the TM and MW was 33 and 53% higher than the control at the HRT of 5 days, respectively. The results show that microwave pretreatment is more effective than thermal pretreatment in increasing the solubilization degree and mesophilic anaerobic biodegradability of sewage sludge.

A Multivariate Assessment of a Risk Model for Juvenile Delinquency With An “Under 12 Offender” Sample

The predictive validity of a hypothesized model of five factors associated with the development of juvenile delinquency was evaluated with 68 children, ages 6 to 11 years, referred for treatment to a clinic for delinquent behavior. Indicators for the predictors were obtained from information identified in the children's clinical files. The criterion measure, collected from parents 10 months after the pretreatment screening, was the t-score on the Delinquent scale of the Child Behavior Checklist. A stepwise multiple regression analysis indicated that aggressiveness and variety of conduct problems accounted for 31% of the variance in delinquent behavior and had the highest relative improvement over chance (RIOC) values. The findings are discussed in terms of practical and policy implications for the early identification of children and youth and the development of early intervention and prevention programs to address the problem of juvenile delinquency.