Relative Volume Ratio Research Articles

Higher stroke risk after carotid endarterectomy and transcarotid artery revascularization is associated with relative surgeon volume ratio: Presented as a full length oral plenary presentation at the Vascular Annual Meeting of the Society for Vascular Surgery, Chicago, Ill, June 19, 2024.

Higher stroke risk after carotid endarterectomy and transcarotid artery revascularization is associated with relative surgeon volume ratio: Presented as a full length oral plenary presentation at the Vascular Annual Meeting of the Society for Vascular Surgery, Chicago, Ill, June 19, 2024.

Higher stroke risk after carotid endarterectomy and transcarotid artery revascularization is associated with relative surgeon volume ratio

ObjectiveAdoption of transcarotid artery revascularization (TCAR) by surgeons has been variable, with some still performing traditional carotid endarterectomy (CEA), whereas others have shifted to mostly TCAR. Our goal was to evaluate the association of relative surgeon volume of CEA to TCAR with perioperative outcomes. MethodsThe Vascular Quality Initiative CEA and carotid artery stent registries were analyzed from 2021 to 2023 for symptomatic and asymptomatic interventions. Surgeons participating in both registries were categorized in the following CEA to CEA+TCAR volume percentage ratios: 0.25 (majority TCAR), 0.26 to 0.50 (more TCAR), 0.51 to 0.75 (more CEA), and 0.76 to 1.00 (majority CEA). Primary outcomes were rates of perioperative ipsilateral stroke, death, cranial nerve injury, and return to the operating room for bleeding. ResultsThere were 50,189 patients who underwent primary carotid revascularization (64.3% CEA and 35.7% TCAR). CEA patients were younger (71.1 vs 73.5 years, P < .001), with more symptomatic cases, less coronary artery disease, diabetes, and lower antiplatelet and statin use (all P < .001). TCAR patients had lower rates of smoking, obesity, and dialysis or renal transplant (all P < .001). Postoperative stroke after CEA was significantly impacted by the operator CEA to TCAR volume ratio (P = .04), with surgeons who perform majority TCAR and more TCAR having higher postoperative ipsilateral stroke (majority TCAR odds ratio [OR]: 2.15, 95% confidence interval [CI]: 1.16-3.96, P = .01; more TCAR OR: 1.42, 95% CI: 1.02-1.96, P = .04), as compared with those who perform majority CEA. Similarly, postoperative stroke after TCAR was significantly impacted by the CEA to TCAR volume ratio (P = .02), with surgeons who perform majority CEA and more CEA having higher stroke (majority CEA OR: 1.51, 95% CI: 1.00-2.27, P = .05; more CEA OR: 1.50, 95% CI: 1.14-2.00, P = .004), as compared with those who perform majority TCAR. There was no association between surgeon ratio and perioperative death, cranial nerve injury, and return to the operating room for bleeding for either procedure. ConclusionsThe relative surgeon CEA to TCAR ratio is significantly associated with perioperative stroke rate. Surgeons who perform a majority of one procedure have a higher stroke rate in the other. Surgeons offering both operations should maintain a balanced practice and have a low threshold to collaborate as needed.

Exploring the nigrostriatal and digestive interplays in Parkinson's disease using dynamic total-body [11C]CFT PET/CT.

Dynamic total-body imaging enables new perspectives to investigate the potential relationship between the central and peripheral regions. Employing uEXPLORER dynamic [11C]CFT PET/CT imaging with voxel-wise simplified reference tissue model (SRTM) kinetic modeling and semi-quantitative measures, we explored how the correlation pattern between nigrostriatal and digestive regions differed between the healthy participants as controls (HC) and patients with Parkinson's disease (PD). Eleven participants (six HCs and five PDs) underwent 75-min dynamic [11C]CFT scans on a total-body PET/CT scanner (uEXPLORER, United Imaging Healthcare) were retrospectively enrolled. Time activity curves for four nigrostriatal nuclei (caudate, putamen, pallidum, and substantia nigra) and three digestive organs (pancreas, stomach, and duodenum) were obtained. Total-body parametric images of relative transporter rate constant (R1) and distribution volume ratio (DVR) were generated using the SRTM with occipital lobe as the reference tissue and a linear regression with spatial-constraint algorithm. Standardized uptake value ratio (SUVR) at early (1-3min, SUVREP) and late (60-75min, SUVRLP) phases were calculated as the semi-quantitative substitutes for R1 and DVR, respectively. Significant differences in estimates between the HC and PD groups were identified in DVR and SUVRLP of putamen (DVR: 4.82 ± 1.58 vs. 2.58 ± 0.53; SUVRLP: 4.65 ± 1.36 vs. 2.84 ± 0.67; for HC and PD, respectively, both p < 0.05) and SUVREP of stomach (1.12 ± 0.27 vs. 2.27 ± 0.65 for HC and PD, respectively; p < 0.01). In the HC group, negative correlations were observed between stomach and substantia nigra in both the R1 and SUVREP values (r=-0.83, p < 0.05 for R1; r=-0.94, p < 0.01 for SUVREP). Positive correlations were identified between pancreas and putamen in both DVR and SUVRLP values (r = 0.94, p < 0.01 for DVR; r = 1.00, p < 0.001 for SUVRLP). By contrast, in the PD group, no correlations were found between the aforementioned target nigrostriatal and digestive areas. The parametric images of R1 and DVR generated from the SRTM model, along with SUVREP and SUVRLP, were proposed to quantify dynamic total-body [11C]CFT PET/CT in HC and PD groups. The distinction in correlation patterns of nigrostriatal and digestive regions between HC and PD groups identified by R1 and DVR, or SUVRs, may provide new insights into the disease mechanism.

PLA-Based Composite Panels Prepared via Multi-Material Fused Filament Fabrication and Associated Investigation of Process Parameters on Flexural Properties of the Fabricated Composite.

This study prepares composite panels with three Polylactic acid (PLA)-based materials via the multi-material fused filament fabrication method. The influences of four processing parameters on the mechanical properties of 3D-printed samples are investigated employing the Taguchi method. These parameters include the relative volume ratio, material printing order, filling pattern, and filling density. A "larger is better" signal-to-noise analysis is performed to identify the optimal combination of printing parameters that yield maximum bending strength and bending modulus of elasticity. The results reveal that the optimal combination of printing parameters that maximizes the bending strength involves a volume ratio of 1:1:2, a material sequence of PLA/foam-agent-modified eco-friendly PLA (ePLA-LW)/glass fiber-reinforced eco-friendly PLA (ePLA-GF), a Gyroid filling pattern, and a filling density of 80%, and the optimal combination of printing parameters for maximum bending modulus involves a volume ratio of 1:2:1 with a material sequence of PLA/ePLA-LW/ePLA-GF, a Grid filling pattern, and 80% filling density. The Taguchi prediction method is utilized to determine an optimal combination of processing parameters for achieving optimal flexural performances, and predicted outcomes are validated through related experiments. The experimental values of strength and modulus are 43.91 MPa and 1.23 GPa, respectively, both very close to the predicted values of 46.87 MPa and 1.2 GPa for strength and modulus. The Taguchi experiments indicate that the material sequence is the most crucial factor influencing the flexural strength of the composite panels. The experiment result demonstrates that the flexural strength and modulus of the first material sequence are 67.72 MPa and 1.53 GPa, while the flexural strength and modulus of the third material sequence are reduced to 27.09 MPa and 0.72 GPa, respectively, only 42% and 47% of the first material sequence. The above findings provide an important reference for improving the performance of multi-material 3D-printed products.

Early Intervention with a Compression Sleeve in Mild Breast Cancer-Related Arm Lymphedema: A 12-Month Prospective Observational Study.

In our previous randomized controlled trial (RCT), the progression/no progression of mild breast cancer-related arm lymphedema (BCRL) was examined among women randomized to a compression group (CG) with a compression sleeve (compression class (ccl) 1) or not (NCG) for 6 months. In the present prospective study, BCRL in the CG and NCG was followed for 12 months. At the end of the RCT, 33 women with mild BCRL were eligible in the CG and 37 in the NCG. The proportional differences in no progression/progression of BCRL were defined as a >2% increase from start of RCT or exceeding 10% in the lymphedema relative volume as measured by the water displacement method. In addition, changes in the lymphedema relative volume and tissue dielectric constant ratio, which measures local tissue water, were examined. At the end of the RCT (i.e., after 6 months), a one-month break of the compression treatment was made in the CG. If the lymphedema relative volume progressed by definition, the compression treatment was resumed and continued, with follow-up of all women at 9 and 12 months. A larger proportion of women in the NCG showed progression (57%, 61%, 67%) compared to the CG (16%, 22%, 31%) at 6, 9, and 12 months (p < 0.001, 0.005, 0.012), respectively. Twelve (33%) women in the NCG did not progress at all. No changes of the lymphedema relative volume and local tissue water were found over time at any follow-ups, but were stable on a low level. To avoid the progression of mild BCRL into a chronic issue in the long-term, compression sleeve ccl 1 may be applied immediately after early diagnosis of mild BCRL.

A review on reactive oxygen species (ROS)-inducing nanoparticles activated by uni- or multi-modal dynamic treatment for oncotherapy.

Cancer seriously threatens human health. As compared to normal tissue cells, tumor cells are generally more susceptible to oxidative stress and accumulate higher concentrations of reactive oxygen species (ROS). Accordingly, nanomaterials-based therapies that boost intracellular ROS generation have recently been effective in targeting and eliminating cancer cells by causing programmed death. This review presents a comprehensive analysis of ROS-generation induced by nanoparticles and critically examines the associated therapies which can be categorized as uni-modal (chemodynamic therapy, photodynamic therapy, sonodynamic therapy) and multi-modal (uni-modal therapy + chemotherapy, uni-modal therapy + uni-modal therapy) therapies. Comparison of the relative tumor volume ratio between the experimental and initial tumor volumes shows that multi-modal therapy significantly outperformed other treatments. However, the limitations of multi-modal therapy are in the difficulties of materials preparation and sophisticated operation protocols, thus limiting its applications in clinical practice. As an emerging treatment modality, cold atmospheric plasma (CAP) is a reliable source of ROS, light, and electromagnetic fields that can be used to implement multi-modal treatments in a simple setting. Therefore, the field of tumor precision medicine is expected to increasingly benefit from these promising and rapidly emerging multi-modal therapies based on ROS-generating nanomaterials and reactive media such as CAPs.

A simple design method of dust explosion venting size at elevated static activation pressure

To develop the application of explosion venting technology in high-pressure vessels, a new model for the design of dust explosion venting size was presented, which took the physicochemical phenomenon deriving from the elevation of the static activation pressure into account. Firstly, for confined pressure rise, the wall quenching effect originating from the dust flame thickness was considered by adopting the three-zone model. Secondly, for the venting pressure rise, the energy loss due to the discharge of high-energy burnt mixture (quantified as the specific surface area loss of the flame) was taken into account and the induced turbulence factor was introduced. Thirdly, for the venting pressure drop, a dynamic pressure relief capability evaluation model which takes into account the flame morphology evolution (tear-shaped flame) and the proportion of discharged mixture (relative volume ratio) at elevated activation pressure was proposed. The predicted maximum reduced pressure and venting size were checked against the PMMA explosion experiments and a more great performance was obtained compared with standards.

Differential volume reductions in the subcortical, limbic, and brainstem structures associated with behavior in Prader\u2013Willi syndrome

Individuals with Prader–Willi syndrome (PWS) exhibit complex behavioral characteristics, including hyperphagia, autistic features, and subsequent age-related maladaptive behaviors. While this suggests functional involvements of subcortical, limbic, and brainstem areas, developmental abnormalities in such structures remain to be investigated systematically. Twenty-one Japanese individuals with PWS and 32 healthy controls with typical development were included. T1-weighted three-dimensional structural magnetic resonance images were analyzed for subcortical, limbic, and brainstem structural volumes, with age as a covariate, using a model-based automatic segmentation tool. Correlations were determined between each volume measurement and behavioral characteristics as indexed by questionnaires and block test scores for hyperphagia (HQ), autistic and obsessional traits, non-verbal intelligence (IQ), and maladaptive behavior (VABS_mal). Compared with the control group, the PWS group showed significantly reduced relative volume ratios per total intracranial volume (TIV) in thalamus, amygdala, and brainstem structures, along with TIV and native volumes in all substructures. While the brainstem volume ratio was significantly lower in all age ranges, amygdala volume ratios were significantly lower during early adulthood and negatively correlated to HQ and VABS_mal but positively correlated to Kohs IQ. Thus, limbic and brainstem volume alterations and differential volume trajectories may contribute to the developmental and behavioral pathophysiology of PWS.

Recovery of ammonia from simulated membrane contactor effluent using bipolar membrane electrodialysis

Abundant in municipal, agricultural, and industrial wastewaters, ammonia is a versatile chemical, which can be used as fertilizer or as a hydrogen carrier for the hydrogen economy. Membrane contactors (MCs) are an effective membrane process for selectively recovering ammonia from a wastewater stream, but the system’s continuous acid consumption and the residual acidity in the produced stream remain a major hurdle. In this study, we propose a chemical-free, electrified process that combines MC with bipolar membrane electrodialysis (BMED) to produce ammonia as a gas from wastewater. We devise three different BMED configurations, and identify the most suitable configuration by examining the impact of different operating conditions including pH, initial ammonia concentration, and relative volume ratios on the ammonia recovery and BMED energy consumption. We demonstrate up to ∼68% recovery of theoretically recoverable ammonia, and attribute the unrecovered fraction primarily to the diffusion of neutral ammonia through membranes. While the system is sub-optimal, the relative energy consumption of the system is comparable to the Haber-Bosch process for conventional ammonia production, with potentially lower energy consumption and higher ammonia recovery through higher initial ammonia concentrations, higher relative volume ratios or alternate BMED configurations.

The invisible arbiter of emulsion structure: insight from an examination of two types of 3-phase emulsions

It has long been established that the equilibrium properties of a water–oil–surfactant system governs the morphology of the emulsion formed—an inherently non-equilibrium system. In this work, we reinforce this concept and bring forward additional insights. Two types of 3-phase emulsions are examined, one obtained from suspension polymerization of silicone and acrylate in an aqueous phase and another obtained from mechanical dispersion of a silicone oil and a sunflower seed oil into an aqueous phase. We show that the specific emulsification process has an impact on the detailed structure of the final multiple droplets. In suspension polymerization, the complete miscibility of silicone with acrylate monomers prior to polymerization renders uniformity in the composition of the starting droplets; hence the final droplets after polymerization all have identical equilibrium tensions as well as relative volume ratios between the separated phases. Consequently, the final droplets have uniformly the same structure as predicted based on thermodynamics. On the other hand, the 3-phase emulsion formed from mechanical dispersion of two immiscible oils in water shows an overall morphology that is predicted by equilibrium tensions, however, a wide variation in the specific geometry is observed. This latter aspect reflects the randomness in drop break-up-and-recombination associated with the homogenization process, which results in variable volume ratio between the two immiscible oils among different droplets.

Liquid-Liquid Phase Separation of Single Optically Levitated Water-Ionic Liquid Droplets in Air.

In this study, to investigate the equilibrium morphology of liquid-liquid phase-separated droplets in air, a temperature-responsive ionic liquid (IL) showing lower critical solution temperature behavior was employed. ILs have negligible vapor pressure and do not evaporate from aerosol droplets during dehumidifying processes. We demonstrated that the liquid-liquid phase separation of single optically levitated aqueous droplets containing the temperature-responsive IL can be induced by controlling the air relative humidity. The formation of liquid-liquid phase-separated droplets of partially engulfed morphology was successfully observed under an optical microscope, and their configurations were compared with those calculated by a thermodynamic model based on interfacial tensions and relative volume ratios of two immiscible phases.

Semi-Supervised Deep Learning-Based Image Registration Method with Volume Penalty for Real-Time Breast Tumor Bed Localization.

Breast-conserving surgery requires supportive radiotherapy to prevent cancer recurrence. However, the task of localizing the tumor bed to be irradiated is not trivial. The automatic image registration could significantly aid the tumor bed localization and lower the radiation dose delivered to the surrounding healthy tissues. This study proposes a novel image registration method dedicated to breast tumor bed localization addressing the problem of missing data due to tumor resection that may be applied to real-time radiotherapy planning. We propose a deep learning-based nonrigid image registration method based on a modified U-Net architecture. The algorithm works simultaneously on several image resolutions to handle large deformations. Moreover, we propose a dedicated volume penalty that introduces the medical knowledge about tumor resection into the registration process. The proposed method may be useful for improving real-time radiation therapy planning after the tumor resection and, thus, lower the surrounding healthy tissues’ irradiation. The data used in this study consist of 30 computed tomography scans acquired in patients with diagnosed breast cancer, before and after tumor surgery. The method is evaluated using the target registration error between manually annotated landmarks, the ratio of tumor volume, and the subjective visual assessment. We compare the proposed method to several other approaches and show that both the multilevel approach and the volume regularization improve the registration results. The mean target registration error is below 6.5 mm, and the relative volume ratio is close to zero. The registration time below 1 s enables the real-time processing. These results show improvements compared to the classical, iterative methods or other learning-based approaches that do not introduce the knowledge about tumor resection into the registration process. In future research, we plan to propose a method dedicated to automatic localization of missing regions that may be used to automatically segment tumors in the source image and scars in the target image.

Evaluation of 18F‐MK‐6240 and 18F‐AV‐1451 tau PET tracers in Alzheimer disease

AbstractBackgroundTwo tau tracers, 18F‐MK‐6240 and 18F‐AV‐1451, have recently been introduced into many studies of Alzheimer disease (AD) but it remains unclear how each tracer evaluates heterogenous tau pathology. In this study we compared the binding of two tau‐specific PET tracers in asymptomatic control (AC) and (AD) participants enrolled in DIAN.MethodNine AC and three AD participants were recruited from DIAN underwent PET/CT imaging twice, one with 18F‐MK‐6240 and the other one with 18F‐AV‐1451 on consecutive days. AC participants were scanned with full dynamic scan (0‐110 min for 18F‐MK‐6240 and 0‐105 min for 18F‐AV‐1451) while 20 min (90‐110 for 18F‐MK‐6240 and 80‐100 min for 18F‐AV‐1451) scan for AD participants. Data were analysed using standardized uptake ratios (SUVr) with whole cerebellum used as a reference tissue from an early frame duration (SUVr0.75‐2.5 min) for all nine AC participants and late SUVr (SUVr20min) for all twelve participants. In addition, centrum semiovale was tested as reference region for SUVr20min. Relative delivery (R1) and distribution volume ratio (DVR = BPND+1) were generated using SRTM2 methods from nine AC dynamic data with cerebellum as reference. Bland–Altman analyses were used to evaluate an agreement between two tracers both for AC and AD participants.ResultBoth tracers show an agreement for relative flow and binding in AC participants as shown in Figure 1. In AD participants, 18F‐MK‐6240 shows a proportionally higher tracer specific binding compare to 18F‐AV‐1451 for regions with an average SUVr value higher than 1.5 as seen in Figure 2. 18F‐MK‐6240 shows relatively lower uptake compared to 18F‐AV‐1451 in AC and significantly higher in AD as in Figure 3. The SUVr attain stable after 80 min post injection for both tracers, but the centrum semiovale reference tissue‐based SUVr shows higher contrast between both tracers than the ones using cerebellum reference tissue (Fig 4).ConclusionBoth tracers show an agreement in AC participants. 18F‐MK‐6240 demonstrates higher SUVr compared to 18F‐AV‐1451 for participants with significant tau deposition in AD. Centrum semiovale is suggested for reference region for both tracers and will be evaluated carefully by the ongoing evaluation study.

Preliminary exploration on the application of hydrogel from acellular porcine adipose tissue to assist lipofilling

To investigate the effect of hydrogel from acellular porcine adipose tissue (HAPA) on the survival of transplanted adipose tissue. For in vitro study, adipose tissue and HAPA-adipose tissue complex were cultured in normoxia and hypoxia atmospheres for 24 and 72 hours. TUNEL and Perilipin immunofluorescence staining were performed to observe the effect of HAPA on apoptosis and survival of adipocities. For in vivo study, 42 healthy male nude mice (4-6 weeks old) weighing 15-18 g were randomly divided into adipose group (group A), 10%HAPA group (group B), 20%HAPA group (group C), 30%HAPA group (group D), 40%HAPA group (group E), and 50%HAPA group (group F) according to different HAPA/adipose tissue volume ratio ( n=7). For each group, 1 mL adipose tissue or HAPA-adipose tissue complex was injected subcutaneously into the dorsum of the nude mice. At 4 weeks after transplantation, 7 nude mice in each group were sacrificed and grafts were harvested, gross observation, volume measurement, ultrasound examination, and histologic staining (HE staining, CD31 and Perilipin immunofluorescence stainings) were applied. Hypoxia showed a tendency of promoting adipose tissue necrosis and apoptosis, while HAPA exhibited an obvious effect of inhibiting cell apoptosis in vitro study ( P<0.05). For in vivo study, grafts of all groups had intact fibrocapsule. No obvious signs of infection and necrosis were observed at 4 weeks. Volume shrinkage was observed in all groups, however, the groups A-D had significantly higher volume retention rate than groups E and F ( P<0.05). Ultrasound examination showed that there were no significant difference in the number and volume of liquify area of the grafts in each group ( P>0.05). With the increase of HAPA's volume ratio, HE staining proved an improved fat integrity while a gradually decreased vacuoles and fibrosis. CD31 immunohistochemical staining showed that the number of neo-vascularisation in groups E and F were significantly higher than those in groups A-D ( P<0.05). Perilipin immunofluorescence staining showed that with the increase of HAPA volume ratio, the number of living adipocytes increased gradually, and more new adipocytes could be seen in the field of vision. As the volume ratio of HAPA gradually increased, the survival of transplanted adipose tissue also increased, but the volume retention rate decreased gradually. 30%HAPA was considered the relative optimal volume ratio for its superior adipose tissue survival and volume retation rate.

A study on in situ measurements of carbonate rock mass degradation in the water-level fluctuation zone of the Three Gorges Reservoir, China

The degradation of rock masses making up carbonate slopes within water-level fluctuation zones after the impoundment of reservoirs is in some cases very intense. This has attracted widespread concern because such degradation can result in evolving geological hazards. Quantitative characterization of carbonate rock degradation is the key to the study of this phenomenon and its subsequent impacts. In this article, a meter-scale representative observation plane (body) is selected as the research object. The continuous medium mode is used to describe a carbonate rock mass with evenly distributed degradation quantitatively by way of a rock mass degradation variable (De), which is the relative area ratio or volume ratio of new macroscopic defects (bedding planes, joints, cracks, pores, holes, etc.) that form in a representative rock mass within a period of time. For carbonate rock with nonuniform degradation, a further rock mass degradation variable, DeA, is developed, which represents the relative area ratio or volume ratio of the new defects within a discontinuous surface or body within a period of time. Direct and indirect methods and formulae for acquiring these values are presented, dependent upon the degradation process involved, such as mechanical erosion, dissolution, and fissure development or expansion. The De value is established based on the measurement of area, volume, trace length, aperture, eroded depth, and acoustic wave velocity. The resulting formulae are used to analyze the degradation of typical rock masses in the Wu Gorge in the Three Gorges Reservoir area quantitatively. From 2010 to 2013, the De value increased continuously from 0.18 to 0.42 in Maocaopo and showed an accelerating trend. For the Qingshi 6# slope, for the period from 2017 to 2019, the De value showed an overall decreasing trend with increasing depth based on acoustic wave velocity data. The De value of the rock mass underground is greater than 0.2 for eight sections and reaches a maximum of 0.69. The degradation of the rock mass presents structural and zonal characteristics in the depth direction. In Jiandaofeng, the De value is calculated to be 0.0041 for the period from 2012 to 2017, while, at the Sunjiawan cliff, the DeA value of a large structural plane reaches to 1.03 after 10 years of impoundment. This research forms a foundation for the measurement of the degradation of rock masses in the Three Gorges Reservoir area and provides basic technical support for the subsequent study of rock degradation and hazard prevention in the area. Furthermore, it also provides a reference for assessing the degradation of rock masses within the water-level fluctuation zone for other areas around the world.

Pancreatic atrophy after gastrectomy for gastric cancer.

To investigate the phenomenon of pancreatic atrophy after gastrectomy for gastric cancer, using computed tomography (CT) volumetry. The subjects of this retrospective study were 77 patients who underwent distal gastrectomy (DG) or total gastrectomy (TG) for pStage I gastric cancer in 2014. The relative pancreatic volume ratio was assessed preoperatively, and then 1 and 5years postoperatively and the results were compared between surgical procedures RESULTS: A total of 14 patients underwent TG with Roux-en-Y (RY) reconstruction, 24 underwent DG with Billroth-I (BI) reconstruction, and 39 underwent DG with RY reconstruction. We observed that the pancreatic volume continued to decrease over the 5years after DG or TG. Furthermore, the incidence of pancreatic atrophy 5years postoperatively was significantly greater after TG than after DG. In patients who underwent DG, a greater incidence of pancreatic atrophy was observed after RY reconstruction than after BI reconstruction, 5years postoperatively. The pancreatic volume continued to decrease after DG and TG for gastric cancer 5years after treatment. TG was associated with a significantly greater incidence of pancreatic atrophy than DG 5years postoperatively, as was RY reconstruction vs. BI reconstruction after DG.

Cerebellar Volumes Associate with Behavioral Phenotypes in Prader-Willi Syndrome

The objective of this study was to investigate lobule-specific cerebellar structural alterations relevant to clinical behavioral characteristics of Prader-Willi syndrome (PWS). We performed a case-control study of 21 Japanese individuals with PWS (age; median 21.0, range 13–50 years, 14 males, 7 females) and 40 age- and sex-matched healthy controls with typical development. Participants underwent 3-Tesla magnetic resonance imaging. Three-dimensional T1-weighted images were assessed for cerebellar lobular volume and adjusted for total intracerebellar volume (TIV) using a spatially unbiased atlas template to give a relative volume ratio. A region of interest analysis included the deep cerebellar nuclei. A correlation analysis was performed between the volumetric data and the clinical behavioral scores derived from the standard questionnaires (hyperphagia, autism, obsession, and maladaptive index) for global intelligence assessment in paired subgroups. In individuals with PWS, TIV was significantly reduced compared with that of controls (p < 0.05, family-wise error corrected; mean [standard deviation], 1014.1 [93.0] mm3). Decreased relative lobular volume ratios were observed in posterior inferior lobules with age, sex, and TIV as covariates (Crus I, Crus II, lobules VIIb, VIIIa, VIIIb, and IX). However, increased ratios were found in the dentate nuclei bilaterally in individuals with PWS (p < 0.01); the mean (standard deviation) × 10−3 was as follows: left, 1.58 (0.26); right, 1.67 (0.30). The altered lobular volume ratios showed negative correlations with hyperphagic and autistic characteristics and positive correlations with obsessive and intellectual characteristics. This study provides the first objective evidence of topographic patterns of volume differences in cerebellar structures consistent with clinical behavioral characteristics in individuals with PWS and strongly suggests a cerebellar contribution to altered functional brain connectivity in PWS.

Explosive behavior during binary-droplet impact on superheated substrates

Droplet impact on superheated smooth solids has attracted enormous attention since Leidenfrost reported the eponymous phenomenon over 250 years ago. The related literature has almost exclusively focused on pure liquids, which maintain their volume integrity even under disruptive nucleate boiling (characterized by the vigorous ejection of tiny droplets from the parent droplet). This study provides evidence of the existence of a new regime – termed explosive boiling – for impact of binary (composed of two miscible liquids) droplets on superheated substrates at temperatures between the respective Leidenfrost temperatures of the two liquid constituents. The distinct characteristic of this regime is a violent breakup of the parent droplet, and is observed only for the lower concentrations of the more volatile component of the mixture. These concentrations seem to maximize the instability of the vapor layer between the droplet and the wall. We explore this previously-unseen behavior, considering the different volatilities of the two liquid constituents and their relative volume ratios in the impacting droplet.

Tunable Two-Layer Dual-Band Metamaterial with Negative Modulus.

A tunable dual-band acoustic metamaterial (AM) with nested two-layer split hollow spheres (TLSHSs) is presented here, which was achieved by adjusting the hole diameter and the ratio of the two layers’ volumes. This work comprises theoretical and numerical studies. Based on sound-force analogy (SFA), TLSHSs can be considered equivalent to a model of two spring oscillators in series. The equations of two resonant frequencies were derived, which precisely provided the relation between two resonant frequencies and the hole diameter as well as the ratio of the two layers’ volumes. The analytical formulas and simulation results by the finite element method (FEM) showed that there were two resonant frequencies for the TLSHSs, and their dynamic modulus became negative near the resonant frequencies. As the the diameter of two holes increased, both of the resonant frequencies underwent a blue shift. As the relative volume ratio increased, both of the resonant frequencies underwent a red shift. The calculation and simulation results were in good agreement. This kind of precisely controllable dual-band AM with negative modulus can easily be coupled to other structures with negative mass density, thereby achieving a double-negative AM in an expected frequency range.

Diameter of Carbon Nanotube-Directed Self-Assembly of Amphiphilic Block Copolymers.

The cooperative self-assembly of nanoparticles and amphiphilic block copolymers has attracted increasing interests as it offers effective routes to achieve nanocomposite supramolecular structures with desired structure and properties. The incorporation of nanoparticles usually tunes the self-assembly structure of block copolymers, as the copolymer–nanoparticle interactions may change the relative volume ratio of hydrophobic block/hydrophilic block copolymers. It should be noted that the micro-size length and the strong nonpolar feature of carbon nanotubes (CNTs) may cause the block copolymer–CNT interactions to differ from the the block copolymer–nanoparticle interactions. Herein, we show that the diameter of CNTs and the copolymer/CNT ratio have a profound effect on the self-assembly behavior of amphiphilic block copolymers. Upon the addition of carboxylated multi-walled carbon nanotubes (c-MWCNTs, diameter <8 nm,) to the methoxy polyethylene glycol-poly (D,L-lactic acid) (MPEG-PDLLA) solution, it is difficult to observe the c-MWCNTs directly in TEM images. However, it has been found that they form supramolecular nanocomposite structures with MPEG-PDLLA. Moreover, these supramolecular structures transform from core–shell spherical micelles into rod-like micelles and then into large composite aggregates with the increase of the c-MWCNT addition. However, in the case of the addition of c-MWCNTs with a diameter of 30–50 nm, the dispersed c-MWCNTs and spherical core–shell micelles could be observed simultaneously in the TEM images at a low c-MWCNT addition, and then the micelle structure disappeared and only well-dispersed c-MWNTs were observed in TEM images at a high c-MWCNT addition. A possible model was proposed to explain the rule of CNTs participating in the formation of copolymer/CNT nanocomposite structures. It was also shown that as-prepared copolymer/CNT supramolecular nanocomposites could be used as drug carriers, enabling the adjustment of the drug loading and release time.