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Vented PMMA dust explosions were conducted in a 20-L spherical chamber with a venting diameter of 80 mm. The flame behaviors and overpressure characteristics at different dust concentrations and static activation pressure were studied. The development mechanism of external flame and the comparison results with two standards were analyzed. The results showed the reduction of dust concentration was necessary for mitigating the external flame, while blindly decreased the static activation pressure would bring greater risk. The characteristics of reduced explosion pressure inside the chamber were analyzed combined with external pressure. Then the rupture mechanism of the venting diaphragm was established based on the elastoplastic analysis. Two empirical modified equation for NFPA68 and EN14491 was established. For NFPA68, the volume correction coefficient of size effect was introduced and the inapplicability of NFPA68 at elevated static activation pressure was attributed to ignoring the compressibility and the choking phenomenon of high-speed fluid.

A simplified bubble model and its solver optimization method are proposed to solve the problem of poor realistic simulation and complex solutions for bubble-motion behavior in water. Firstly, the internal velocity of the bubble was avoided, and the bubble model was established by only considering the net flux of the inlet and outlet bubbles, which reduced the computational complexity. The bubble constraint was then introduced into the motion equation of water, and the mixed Euler–Lagrangian method was used to solve it. FLIP particles tracked the bubble position, velocity, and deformation, and the mesh updated the vector field. At the same time, the viscosity term was simplified. Finally, it was combined with implicit incompressible SPH particles to achieve the purpose of volume correction. The experimental results show that the method in this paper can present a simulation effect of bubbles in water with rich detail and a realistic sense, whether compared with actual pictures or with existing methods.

Background Synthetic soft tissue fillers frequently used to restore facial volume do not provide a regenerative framework, limiting their sustained efficacy. Autologous fat transfer for facial rejuvenation supports tissue regeneration but has unpredictable outcomes depending on the quality of harvesting, processing, and implantation. Aims Exploration of the pros and cons of available tissue fillers and the role of an injectable Allograft Adipose Matrix (AAM) for facial rejuvenation. Methods The results of a literature review conducted by two clinicians with extensive experience in this field were discussed by a panel of dermatologists and surgeons who regularly treat patients with signs and symptoms of facial aging. A manuscript was prepared and reviewed by the panel taking into account the evidence and their clinical experience treating patients for facial rejuvenation. Results Facial rejuvenation needs to address the volume deficiency and repositioning of ptotic soft tissues. Frequently used synthetic fillers are suitable candidates for improving the facial appearance of fine lines and for molding. A better understanding of facial volume loss has allowed the use of adipose fat cells for facial rejuvenation. The injectable AAM is readily available and provides a regenerative framework for sustainable results. Prospective clinical and randomized studies support the effective and safe use of AAM for facial rejuvenation. Conclusion AAM may offer an alternative to synthetic fillers and autologous fat implantation in the face without the cumbersome process of fat harvesting and processing. More robust studies are to confirm the positive results obtained in smaller studies using the soft tissue bio stimulatory injectable.

This research proposes a robust correction procedure to improve inaccuracies around edges and corners inherent to thin shell electromagnetic problems by means of perturbation technique. This proposal is developed with three processes: A classical thin shell approximation replaced with an impedance-type interface condition across a surface is first considered and then a volume correction is introduced to overcome the thin shell approximation. However, the volume correction is quite sensitive to cancellation errors, with dramatic effects in the calculation of the local fields near edges and corners. Therefore, a robust correction procedure is added to improve cancellation errors of the volume correction. Each step of the developed method is validated on the practical problem.

Breast asymmetry is a common problem in augmentation mammoplasty. The notorious different implant volume approach has been shown ineffective because of recurring breast asymmetry in course of time. A uniform approach to the correction of breast asymmetry is still unavailable. Four hundred and two patients underwent breast asymmetry correction with augmentation mammoplasty. We have described our technique providing good results in breast asymmetry correction using similar volume implants and resecting glandular tissue from the larger breast. Good aesthetic results were reported by all patients. No additional management of asymmetry was required in 290 patients (72%). One hundred and twelve (28%) patients received an additional correction of breast asymmetry due to breast ptosis, different levels of submammary folds. No major volume correction was required, and no implant change was needed. Our method of breast asymmetry correction allows using identical implants and presents good long-term results and no relapse. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Aim: Is to evaluate the accuracy of orbital volume correction using pre-adapted titanium mesh with the aid of stl model of corrected orbit.Patients and methods: Ten patients with unilateral orbital floor fracture were included. The cases were divided into two equal groups. Manual group where titanium mesh was manually adapted intra-operatively. STL group where titanium mesh was adapted pre-operatively using stl model of corrected orbit. Orbital volume measurements based on CT images were used to trace the degree of correction in each group. Paired samples t test was used for statistical analysis.Results: There was statistical significant difference in the correction of orbital volume in each group. However, comparison between the two groups revealed no statistical significant difference in the percentage of correction, where the mean percentage of correction in stl group was (102.8 ± 4.4) versus (98.4± 2.6) in the manual group.Conclusion: Application of pre-adapted titanium mesh by the aid of stl model provide successful tool for correction of orbital volume secondary to orbital floor fracture with less operative time and effort especially in comminuted fractures.

This paper presents a robust correction procedure based on the perturbation method to reduce errors around edges and corners related to thin structures via a sub-domain technique. The idea of the method is considered as several scenarios. A sub-domain involving with stranded or massive inductors alone is initially considered. A shielding approximation that neglects end and border effects is then added with an impedance-type condition across a surface. A volume correction is finally introduced to improve the inaccuracies from the shielding approximation. But, this volume correction usually faces with cancellation errors in the calculation of the local fields around corners and curvatures. Thus, in order to treat this inconvenience, a robust correction procedure is developed to take cancellation errors into account. Each sequence of the method is considered separately on its own mesh and domain without depending on other meshes and domains.

OBJECTIVE: The aim of this study was to quantitatively assess the performance of metal artifact reduction (MAR) algorithms on the volume of metal cylinders, considering the influence of materials, positions, and fields of view (FOVs), by using 3 cone beam computed tomography (CBCT) devices (NewTom VGi evo, Picasso Trio, and ProMax 3-D Max). STUDY DESIGN: Nine phantoms containing cylinders of amalgam, copper-aluminum (CuAl) metal alloy, and titanium, combined in up to 3 positions, were scanned by using 2 different FOVs. MATLAB software was used to evaluate the differences between volumes before and after MAR application, and the possible interference of materials, positions, and FOVs. Wilcoxon's test and the Kruskal-Wallis test were used at a level of significance of 5%. RESULTS: In general, images containing amalgam and CuAl showed a significant difference in volume before and after MAR application. However, no significant difference after MAR was observed (P > .05) relative to positions and FOVs. MAR had an impact on the cylinder volumes only in the NewTom VGi evo and ProMax 3-D Max scanners. CONCLUSIONS: The performance of MAR algorithms in volume correction of metal objects is dependent on the materials and the CBCT unit. ispartof: ORAL SURGERY ORAL MEDICINE ORAL PATHOLOGY ORAL RADIOLOGY vol:130 issue:3 pages:328-335 ispartof: location:United States status: published

Acute renal failure remains a significant concern in all patients with the coronavirus disease 2019 (COVID-19) infection. Management is particularly challenging in critically ill patients requiring intensive care unit (ICU) level of care. Supportive care in the form of accurate volume correction and avoiding nephrotoxic agents are the chief cornerstone of the management of these patients. The pathophysiology of acute renal failure in COVID-19 is multifactorial, with significant contributions from excessive cytokine release. Gaining a better insight into the pathophysiology of renal failure will hopefully help develop more directed treatment options. A considerable number of these patients deteriorate despite adequate supportive care owing to the complexity of the disease and multi-organ involvement. Renal replacement therapy is used for a long time in critically ill septic patients who develop progressive renal failure despite adequate conservative support. Timing and choice of renal replacement therapy in critically ill COVID-19 patients remains an area of future research that may help decrease mortality in this patient population.

The second gas effect occurs when high inspired concentrations of a first gas, usually nitrous oxide, enhance the uptake of other gases administered simultaneously. The second gas effect is greater in blood than in the gas phase, persists well into the period of nitrous oxide maintenance anesthesia, increases as the degree of ventilation-perfusion mismatch increases, and is most pronounced with the low soluble agents in current use. Yet, how low gas solubility and increased ventilation-perfusion mismatch can combine to improve gas transfer remains unclear, which is the focus of the present study. Specifically, we have used a two-step model of gas exchange to separate the effect of gas volume contraction, which accompanies the first gas uptake, from other factors. Step 1 involves the uptake of the second gas at constant volume. Contraction of gas volume takes place in step 2 and is most effective in transferring further amounts of gas to blood if the volume of second gas exposed to the contraction is maximized, i.e., if the loss of second gas in step 1 is minimized. Minimization depends on having a gas with a low solubility in blood and increases as the degree of ventilation-perfusion mismatch increases. The effectiveness of the contraction also requires a favorable alignment with the retained second gas. Alignment depends on the solubility of both gases and the degree of ventilation-perfusion mismatch. The model is fully consistent with classical concepts of gas exchange. NEW & NOTEWORTHY Gas exchange in the lung can always be represented as the sum of two components: gas exchange at constant volume followed by gas exchange on volume correction. Using this sequence to study the second gas effect, low gas solubility and increased ventilation-perfusion mismatch are shown to act together to enhance second gas uptake. While appearing to contravene classical concepts of gas exchange, a detailed theoretical analysis shows it is fully consistent with these concepts.

Background Aesthetic physicians have several hundred injectable products to select from. Due to differences in their manufacturing technology, these products display varying biophysical qualities, such as their cohesivity and lift capacity. Currently, there is no guidance to objectively selecting the best product for a particular patient. Therefore, an algorithmic approach is required to take specific skin characteristics into consideration. Objectives To evaluate (1) whether subjects seeking injectable treatments for midfacial volume loss and/or contour deficiency can be stratified based on specific skin characteristics (eg, thickness, fat quantity, bony structure) and (2) whether particular hyaluronic acid fillers perform best when used in such particular strata. Methods This was a prospective, Phase IV, open-label, single-center clinical trial. Thirty female patients with midface/cheek volume loss and/or contour deficiency were recruited (mean age, 53.5 years; SD, 12.57; range, 35–75 years). Subjects were treated with either Restylane Lyft (HAL) or Restylane Volyme (HAV) and followed for 4 months post-injection. Treatment allocation was based on the treating physician’s clinical evaluation and compared with ultrasound evaluation. Ultrasound images were used to confirm stratification. Safety and efficacy assessments were performed at each study visit: baseline, week 2, week 4, week 8, and week 16. Subgroup analyses evaluated whether particular strata performed best when treated with specific products. Results The 2 investigative products varied in their efficacy, depending on the characteristics of the subject. Conclusions The use of a treatment algorithm may improve outcomes for patients seeking injectable treatments for midfacial volume loss and contour deficiencies. Level of Evidence: 2

An ellipsoid-based, improved kNN entropy estimator based on random samples of distribution for high dimensionality is developed. We argue that the inaccuracy of the classical kNN estimator in high dimensional spaces results from the local uniformity assumption and the proposed method mitigates the local uniformity assumption by two crucial extensions, a local ellipsoid-based volume correction and a correction acceptance testing procedure. Relevant theoretical contributions are provided and several experiments from simple to complicated cases have shown that the proposed estimator can effectively reduce the bias especially in high dimensionalities, outperforming current state of the art alternative estimators.

The information given in the scientific literature sources about the transplantation of autologous adipose tissue (AAT) enriched with stem cells (SC) in cases of breast shape and volume correction (in both aesthetic indications and elimination of postoperative deformities) is characterized by versatile results. This circumstance promotes the purposeful study about the possibilities of modern surgical technologies in use of mesenchymal SC (MSCs) of autologous adipose tissue in cases of mammoplasty. The information on the basic techniques of mesenchymal SC isolation from the AAT has been analyzed. The data of cytological criteria were studied separately that allow to relate this biological substance to the SC. Technical features of stem cells transplantation derived from the autologous adipose transplant in cases of mammoplasty are demonstrated. According to opinion among the competent researchers, elimination of postoperative deformities using cellular technologies is a promising scientific direction of medicine.

The original proof of Dacorogna-Moser theorem on the prescribed Jacobian PDE, \begin{document}$\text{det}\, \nabla\varphi=f$\end{document} , can be modified in order to obtain control of support of the solutions from that of the initial data, while keeping optimal regularity. Briefly, under the usual conditions, a solution diffeomorphism \begin{document}$\varphi$\end{document} satisfying \begin{document}$ \text{supp}(f-1)\subset\varOmega\Longrightarrow\text{supp}(\varphi-\text{id})\subset\varOmega $\end{document} can be found and \begin{document}$\varphi$\end{document} is still of class $C^{r+1, α}$ if $f$ is $C^{r, α}$, the domain of $f$ being a bounded connected open \begin{document}$C^{r+2, α}$ $\end{document} set \begin{document}$\varOmega\subset\mathbb{R}^{n}$\end{document} .

We consider the problem of finding a mesh such that 1) it is the closest, with respect to a suitable metric, to a given source mesh having the same connectivity, and 2) the volumes of its cells match a set of prescribed positive values that are not necessarily equal to the cell volumes in the source mesh. This volume correction problem arises in important simulation contexts, such as satisfying a discrete geometric conservation law and solving transport equations by incremental remapping or similar semi-Lagrangian transport schemes. In this paper we formulate volume correction as a constrained optimization problem in which the distance to the source mesh defines an optimization objective, while the prescribed cell volumes, mesh validity and/or cell convexity specify the constraints. We solve this problem numerically using a sequential quadratic programming (SQP) method whose performance scales with the mesh size. To achieve scalable performance we develop a specialized multigrid-based preconditioner for optimality systems that arise in the application of the SQP method to the volume correction problem. Numerical examples illustrate the importance of volume correction, and showcase the accuracy, robustness and scalability of our approach.

Metopic synostosis results in a keel-shaped forehead, reduced frontal intracranial volume (ICV), and lower frontal to total volume ratio. The ratio improves with cranioplasty, but at 3 years of age, the ratio is still not normalized when compared to that in normal children. The aim of the present study was to investigate whether a low frontal to total ICV ratio at 3 years of age was due to relapse or insufficient correction.All children surgically treated for metopic synostosis in combination with a spring at Sahlgrenska University Hospital with subsequent spring extraction between 2002 and 2008 (n = 20) were included. A MATLAB program was used to measure frontal and total ICV.Preoperatively, the frontal to total ICV ratio was 9.8 ± 1.3% (mean ± standard deviation). At spring removal, 6 months after cranioplasty, the ratio had increased to 11.8 ± 2.4%. At 3 years of age, the ratio was 11.6 ± 1.9%. In age-matched normal children, the ratio was 14.4 ± 1.9% preoperatively, 15.3 ± 2.2% at time of spring extraction, and 13.4 ± 1.4% at 3 years of age.Cranioplasty thus improved the frontal to total ICV ratio, but did not normalize it. The ratio did not change from 6 months after the cranioplasty to 3 years of age. These results indicate that a more pronounced frontal volume correction during cranioplasty is necessary to achieve a normalized distribution of ICV in metopic synostosis.

Purpose We compared the accuracy of orbital volume correction between the transorbital and transantral reconstructive techniques. Materials and Methods A retrospective cohort study was performed of patients who had undergone repair of isolated, unilateral orbital floor blowout fractures at Legacy Emanuel Hospital from 2013 to 2018. A total of 21 patients were identified and included in the predictor variable cohorts of the transorbital versus transantral repair technique. The outcome variable of orbital volume correction was evaluated by comparing the volume of the postoperative repaired orbits with that of the contralateral noninjured orbits. Additional ordinal variables analyzed included the preoperative orbital defect size and analysis of the transantral cohort stratified by the plating technique used. Data were assessed using analysis of variance and paired t tests. Results A transantral approach was used for orbital repair in 9 patients. In these patients, the postoperative orbital volume in the injured orbit was 2.69% greater than that in the uninjured orbit. The 12 patients who had undergone transantral repair had a postoperative orbital volume in the injured orbit that was 0.56% smaller than that of the uninjured orbit (P = .033). Division of the transantral cohort into 2 different plating techniques identified a less than 1% difference in mean orbital volume correction between the 2 techniques (P = .104). The average defect volume before transorbital repair was 4.87 cm3 compared with 5.22 cm3 for transantral repair (P = .907). Conclusions The results from the present study have shown that the accuracy of orbital volume correction using the transantral approach will be comparable to that of the transorbital approach, as shown by a small, but statistically significant, increased accuracy in the volume correction with the transantral approach. Additional investigation to establish clinical correlations with these findings should be conducted.

The goal of this manuscript is the use of the statistical methods to analyze differences caused by the application of the correction methods defined on different standards for the measurement of the volume of liquid petroleum derivatives. This correction is necessary because pressure and temperature variations can cause differences between measurements made by the customer and supplier due to operational condition variations. To standardize this measurement, it was established that all volumes used on transactions in Brazil should be corrected to a base condition (20 °C and 101.325 kPa). To study these possible differences, the applied methodology uses statistical distributions that model the density of the products during the production process and, i.e., uses data collected during certain periods. Corrected density values are then obtained for each method. With these values in hand, a hypothesis test based on measurement uncertainty shows that numerical differences don’t always have statistical significance.

Before the design of the nuclear facility, it is necessary to estimate the dose caused by radioactive material released into the environment during the course of the serious accidents. Semi-infinite hemisphere geometric model is established to estimate the personal external exposure dose outdoors in which the distribution of the nuclides is assumed to be uniform. The exposed staffs are in a limited cubic space when using this model to evaluate the controllability of the main control room. Thus, the volume correction factor is needed to correct the dose, whose traditional expression is f = 352/pow(V, 0.338). The formula cannot satisfy the requirement of higher accuracy due to the neglect of the influence of the shape of geometric model and γ-rays energy. Usually the actual control room is a cube and the γ-rays energies emitted from various nuclides are different. In order to calculate the accurate volume correction factor of main control room under different geometric conditions, a finite cubic geometric model is established in this paper. The length and width of the model are between 6m and 50 m, the height is between 4m and 6m, and γ-ray energy respectively are 0.05, 0.2, 0.733, 1.2 and 3 MeV, respectively. The effective volume values for different conditions are calculated by the Monte-Carlo program, and 318 groups of results are obtained. The calculated volume dose rate of 360m × 360m × 255m (assuming semi-infinite) cube at 733keV γ-rays energy is taken as a criterion, whose ratio of the other calculation results is the new volume correction factor value. By comparing two volume correction factors, the relative discrepancies are within 3 folds, proving that the calculation result is reasonable and feasible. The new volume correction factor varies with γ-rays energy and the shape of the geometric model. A neural network model corresponding to the volume correction factor is developed to apply to more cases. 80% of the results are randomly selected as the training set of neural network. The remaining 20% of the result as the test set of the cross-test is to predict the results of the trained neural network, whose relative errors are less than 5%. The neural network model can obtain the volume correction factor under different geometry and γ-ray energy conditions. Finally, a volume correction factor library is established, which can provide a powerful reference to obtain the volume correction factor of the limited space model such as the main control room.

Sex differences exist in behaviors, disease and neuropsychiatric disorders. Sexual dimorphisms however, have yet to be studied across the whole brain and across a comprehensive time course of postnatal development. Here, we use manganese-enhanced MRI (MEMRI) to longitudinally image male and female C57BL/6J mice across 9 time points, beginning at postnatal day 3. We recapitulate findings on canonically dimorphic areas, demonstrating MEMRI’s ability to study neuroanatomical sex differences. We discover, upon whole-brain volume correction, that neuroanatomical regions larger in males develop earlier than those larger in females. Groups of areas with shared sexually dimorphic developmental trajectories reflect behavioral and functional networks, and expression of genes involved with sex processes. Also, post-pubertal neuroanatomy is highly individualized, and individualization occurs earlier in males. Our results demonstrate the ability of MEMRI to reveal comprehensive developmental differences between male and female brains, which will improve our understanding of sex-specific predispositions to various neuropsychiatric disorders., Sex differences occur in various aspects of neurodevelopment. Here the authors use manganese-enhanced MRI at nine different postnatal stages to detail the development of structural sex differences in the mouse brain.

We initiate a systematic method to calculate both the finite volume energy levels and form factors from the momentum space finite volume two-point function. By expanding the two point function in the volume we extracted the leading exponential volume correction both to the energy of a moving particle state and to the simplest non-diagonal form factor. The form factor corrections are given in terms of a regularized infinite volume 3-particle form factor and terms related to the L\"usher correction of the momentum quantization. We tested these results against second order Lagrangian and Hamiltonian perturbation theory in the sinh-Gordon theory and we obtained perfect agreement., Comment: 58 pages, 1 figure

A monthly to daily streamflow disaggregation method is presented as part of an emerging water quality model designed to link with established monthly hydrology and yield models. The daily time step is assumed necessary for simulating water quality dynamics. The method is tested on two catchments in South Africa where observed daily flow data are available. The model includes a volume correction process to ensure daily sums are equal to input monthly flows and this reduces the sensitivity of the results to some model parameters. The sequences of events in the input daily rainfall must be representative of the catchment. Model validation against observed flows achieved Nash-Sutcliffe efficiency values ranging from 0.75 to 0.94 and initial applications of a water quality component suggested little difference between using observed and disaggregated flows. The main practical advantages are simplicity and the fact that the method builds on the experience of existing monthly models. Editor D. Koutsoyian...

Sex differences exist in behaviours, disease and neuropsychiatric disorders. Sexual dimorphisms however, have yet to be studied across the whole brain and across a comprehensive time course of postnatal development. We used manganese-enhanced MRI (MEMRI) to longitudinally image male and female C57BL/6J mice across 9 time points, beginning at postnatal day 3. We recapitulated findings on canonically dimorphic areas, demonstrating the ability of MEMRI to study neuroanatomical sex differences. We discovered, upon whole-brain volume correction, that neuroanatomical regions larger in males develop early in life, while regions larger in females develop in peripubertal life. Furthermore, we found groups of areas with shared sexually dimorphic developmental trajectories that reflect behavioural and functional networks, and expression of genes involved with sex processes. Our results demonstrate the ability of MEMRI to reveal comprehensive developmental differences between male and female brains, which will improve our understanding of sex-specific predispositions to various neuropsychiatric disorders.

Outlier detection in compositional grading data of a reservoir fluid is the main objective of the present study. The experimental data of a petroleum reservoir fluid including the mole fractions of the fluid components at different depths (from around 1000 to about 1400 m) and at constant temperature of 361.15 K are investigated. The utilized algorithm applies the basis of a mathematical approach, in which the statistical Hat matrix, Williams plot, and the residuals of a compositional grading model results bring about the probable outliers detection. The range of applicability of the applied model and quality of the existing experimental data are also investigated. The reported results of a previously developed model using the Soave–Redlich–Kwong equation of state (SRK EoS) with Peneloux volume correction are employed to evaluate the compositional analysis of the species in different depths of the fluid column. It is interpreted from the obtained results that the applied model for estimation of the compositional gradients has wide ranges of applicability. In addition, we may conclude that there is no outlier or probable doubtful datum in the investigated experimental datasets.