Change In Total Volume Research Articles

Emergency Medical Services and Police Utilization for Pediatric Mental and Behavioral Health Concerns Within a Large Hospital System.

This study aimed to compare emergency medical services (EMS) and police utilization trends, epidemiology, and emergency department (ED) outcomes between pediatric patients with mental or behavioral health (MBH) emergencies and those with non-MBH concerns transported to a large children's hospital system. This was a retrospective cohort study of patients aged 5 to 18 years transported via EMS and police to two EDs affiliated with a children's hospital from January 2012 through December 2020. Data were abstracted from electronic hospital records. Encounters for MBH emergencies were identified using diagnostic codes and chief complaints. Trends of EMS and police transports of patients with MBH emergencies were examined. Patient demographics and ED outcomes were compared between children presenting with MBH emergencies and those with non-MBH concerns. During the 9-year study period, out of 40,663 transports to the EDs, 36,137 (89%) arrived via EMS, and 4,526 (11%) arrived via police. A total of 10,250 (28.4%) EMS transports were for MBH emergencies. The volume of patients transported by EMS for MBH emergencies increased by 1.4% per year (P < 0.01) with no significant change in total EMS patient volumes. Patients with MBH emergencies transported by EMS were more likely to be older, female, of White race, and publicly insured; require restraint in the ED; and be admitted (P < 0.001). Of police transports, 4153 (91.8%) were for MBH emergencies, with no statistical change in the proportion of police transports that were for MBH emergencies. Police-transported MBH patients compared to non-MBH police-transported patients were more likely to be younger, female, and of White race (P < 0.001); 8.7% required mechanical/physical restraints in ED, 6.7% required pharmacologic restraint medications in ED, and 53% were admitted. The proportion of pediatric transports for MBH emergencies by EMS is rising and comprises the majority of police transports. Distinct from non-MBH pediatric patients transported, MBH patients necessitate significant ED resources, including ED-administered restraints and admission, highlighting their unique burden on the prehospital and ED systems.

Transileocolic Portal Vein Embolization Increases Remnant Liver Volume After Major Hepatectomy.

Transileocolic portal vein embolization (TIPE) may reduce the risk of liver failure after massive hepatectomy. However, convincing evidence of its usefulness in this regard is yet to be reported. Therefore, this study aimed to investigate the use of TIPE after massive hepatectomy. Twelve patients who underwent TIPE were included. Pre- and postoperative liver volumetry was determined using a 3D simulator with computed tomography. After TIPE, the percent change in total liver volume was 104.0%±13.1% (p=0.08). Conversely, the percent increase in remnant liver volume (ml)/total liver volume (ml) and remnant liver volume (ml)/standard liver volume (ml) was 122.9%±18.6% (p<0.001) and 132.2%±19.6% (p<0.001), respectively. TIPE operation time was 125±84.6 min, with minimal blood loss in all cases. Postoperative hospitalization duration during TIPE was 4.5±2.6 days. No TIPE-related complications occurred in any patient. TIPE is beneficial and safe when preoperative volumetry indicates that the remaining liver volume is inadequate and inoperable.

Biodegradable Citrate‐Based Polymers Enable 5D Monitoring of Implant Evolution

AbstractBiodegradable tissue engineering scaffolds have garnered increasing interest for their role in providing mechanical support, promoting tissue regeneration, and eliminating the need for removal. However, the in vivo degradation processes remain challenging to track. Here, a novel biodegradable polymer, N‐methyldiethanolamine (MDEA) and Gadolinium(III) diethylenetriamine pentaacetate (Gd‐DTPA) modified biodegradable photoluminescent polymers (BPLPMGd), which combines near‐infrared (NIR) fluorescence and magnetic resonance (MR) dual‐modality imaging are introduced to monitor scaffold degradation in vivo. The chemical structure of BPLPMGd is characterized and its dual‐imaging properties in vitro are evaluated. Subsequently, non‐invasive dual‐modality imaging to track the degradation of implanted BPLPMGd scaffolds is performed in a rat model, comparing these results with histological data. This approach reveals that BPLPMGd enables reliable non‐invasive tracking of the degradation, where NIR fluorescence imaging offers a qualitative and quantitative analysis of scaffold mass loss, total volume and solid content changes, while magnetic resonance imaging (MRI) details structural and morphological changes, allowing for 5D monitoring of implant degradation, including 3D structure, location, mass, volume, and geometry. The combination of these imaging modalities provides a comprehensive view of scaffold degradation, where the synergistic use of both yields results greater than either modality alone, offering unprecedented 5D information of implantable devices. This innovative approach has potential applications in regenerative engineering and beyond.

Integrated multi-omics predictive analysis of atherosclerosis: a sub-study from the Mineralocorticoid Receptor Antagonism in Diabetic Atherosclerosis (MAGMA) trial

Abstract Background/Introduction Mineralocorticoid receptor (MR) antagonists (MRA) are beneficial in cardiorenal outcomes in randomized controlled trials but the mechanisms are unclear. MAGMA was an NHLBI sponsored randomized, double-blind, placebo controlled, 12-month trial comparing Spironolactone (n = 37) vs. placebo (n = 42) in Type 2 diabetics with CKD stages 3-4 on maximal renin-angiotensin system (RAS) blockade and a prior atherosclerotic event and/or left ventricular (LV) hypertrophy. The primary outcome of percent (%) change in total aortic wall volume (TWV) at 12 months, measured by magnetic resonance imaging (MRI), was significantly reduced by Spironolactone. Purpose/Originality The purpose of this analysis was to understand mechanistic pathways of MRAs using a multi-omics approach that could help tease out molecular mechanisms of benefit. Revealing for the first time which of these integrated pathways are predictive of the primary outcome will help design treatments for targeted interventions. Methods Plasma and peripheral blood mononuclear cells from patients randomized to Spironolactone or placebo at baseline and 3-months were measured for aptamer-based proteomic biomarkers (7,596 proteins) and 10-X platform-based single-cell RNA-sequencing (scRNAseq), respectively. Pre-selected candidate predictors were used as inputs of a predictive model of changes of TWV. We fit a Mixed-Multivariate Random Forest (RF) model, a variation of the RF supervised tree-based machine learning method to take the experimental design into account in the regression formulation. The two sources of "omics predictors" were integrated into a supervised multi-omics model to jointly explain the outcome using an extension of Sparse Generalized Canonical Correlation Analysis (SGCCA). Integrated multiome functional analyses with graphical visualizations were carried out by statistical enrichment analysis using Over Representation Analysis (ORA) and Gene Set Enrichment Analysis (GSEA) against databases of gene ontologies, biological pathways, putative regulatory motifs, proteins, or disease annotations. Results The plasma proteome in response to Spironolactone revealed downregulation of MR targets including fibrosis, immune activation/inflammation, leukocyte activation, proliferation and pathways involved in cytokine stimulation. scRNAseq pathways revealed negative regulation of cytokines production such as IL-2 and redistribution of multiple cell types. Predictors of plaque progression involved cytokine-receptor, complement-coagulation, cell adhesion and axonal guidance targets. Multiome integrated functional analyses results of predictive pathways will be presented. Conclusions The changes in plasma proteomic profile with Spironolactone were consistent with the phenotype of reduced atherosclerosis and downregulation of multiple inflammatory, immune response and profibrotic pathways.

Association between lipoprotein particle concentration and size and progression of coronary plaque: the MACS Longitudinal Coronary CT angiography study

Abstract Background People living with HIV have greater risk of cardiovascular diseases (CVD) than people without HIV and tend to have different risk profiles, including higher serum triglycerides and lower LDL cholesterol levels. Nuclear magnetic resonance (NMR) provides a detailed phenotype of lipoproteins. Purpose To examine the associations between lipoprotein particle concentrations and size and progression of coronary artery plaque among people living with and without HIV, and whether these associations differ by HIV serostatus. Methods Men with no clinical CVD in the Multicenter AIDS Cohort Study (MACS) who underwent a coronary CT angiography at baseline (2010-13) and follow-up (2015-17) were included. NMR spectroscopy was completed on fasting serum samples at baseline. Logistic regression models for the change in total coronary plaque volume (in tertiles) were estimated with NMR-derived lipoproteins as predictors. Levels were log-transformed and standardized to make results comparable. Models were adjusted for demographics, statin use and HIV serostatus (model 1) with addition of CVD risk factors (model 2). Interactions by HIV serostatus were also tested. Results A total of 549 men (314 with HIV; 235 without HIV) were included. Mean age was 53 ±7 years; 58% were White, 30% Black, and 12% Hispanic. Coronary plaque was present in 70% and plaque volume progressed in 79% of the cohort. Among men with HIV, 81% had undetectable HIV RNA and 12% had a diagnosis of AIDS at baseline. Men with HIV had significantly higher levels of small LDL-P, and total, medium and large VLDL-P levels compared to men without HIV, and lower levels of total, small and large HDL-P (Table 1). Men with HIV had significantly greater progression of plaque volume (37 mm3) compared to men without HIV (31 mm3, p&amp;lt;0.05). Levels of total and small LDL-P concentrations were directly associated with plaque progression, whereas large HDL-P was inversely associated with plaque progression in the combined sample (Model 2). Associations between total and small LDL-P with plaque progression were stronger in men with HIV than in men without HIV in models 1 and 2 (interaction p&amp;lt;0.01). While associations in fully adjusted models for total VLDL-P and small VLDL-P were significant in men without HIV, there were no significant associations between these particle concentrations with coronary plaque progression among men without HIV (interaction p&amp;lt; 0.01) (Model 2, Table 2). Conclusion Associations between lipid particle concentrations and coronary plaque progression differed between men with and without HIV, with stronger associations seen in men without HIV for total and small LDL-P. Despite having higher VLDL and lower HDL particle concentrations at baseline, these particle concentrations were only associated with plaque progression in men without HIV. Further research is needed to elucidate HIV specific factors for plaque progression to tailor risk reduction strategies.

Effect of soft tissue volume on midfacial gingival margin alterations following immediate implant placement in the esthetic zone: a 1-year randomized clinical and volumetric trial.

The current trial evaluated the midfacial gingival margin changes, volumetric, radiographic and clinical alterations 1-year following immediate implant placement with customized healing abutment (IIP + CHA) either solely, or in combination with xenograft (IIP + Bonegraft) or with connective tissue grafting (IIP + CTG) at sites with thin labial bone in the esthetic zone. Thirty-nine non-restorable maxillary teeth indicated for extraction in the esthetic zone were included. Participants were randomly assigned into three equal group; IIP + Bonegraft (Control), IIP + CTG and IIP + CHA. Midfacial gingival margin changes(mm) as primary outcome, labial soft tissue contour change(mm), interdental tissue height changes and total volume(mm3) were assessed. Amount of bone labial to the implant and crestal bone level changes were also recorded. All outcomes were measured 1-year post-operative. The midfacial gingival margin changes demonstrated a significant difference (P ≤ 0.05) between the groups showing -0.98, -0.74 and -1.54mm in sites treated with IIP + Bone graft, IIP + CTG and IIP + CHA respectively after1-year. While labial soft tissue contour change (mm), total volume (mm3) and distal interdental tissue height changes (mm) revealed a significant difference after one-year between the studied groups, yet mesial interdental tissue height changes showed no difference (P > 0.05). Both IIP + Bone graft and IIP + CHA groups revealed a significant positive correlation between the total volume loss (mm3) after 1 year and mid-facial gingival margin changes (P ≤ 0.05). However, no significant correlation was observed in the IIP + CTG group (P = 0.63). CBCT measurements showed a significant difference in crestal bone changes between the three groups (P ≤ 0.05), yet, there was no significant difference regarding mean amount of bone labial to the implant(P > 0.05). This investigation suggests that the mere presence of CTG simultaneous with IIP in the anterior maxilla reduced the midfacial gingival margin alterations (mm), besides, CTG decreased the overall volume loss (mm3) by 5-folds compared to the other studied groups after one year. Meanwhile, using CHA alone with IIP failed to maintain the peri-implant soft tissues contour. The current trial was retrospectively registered at Clinical trials.gov (ID: NCT05975515, Date: 27-July-2023).

Correlation of CT measurements of total body gas volume and hounsfield units with post-mortem interval

Accurate estimation of the post-mortem interval (PMI) may be a matter of crucial importance in forensic investigations.A preliminary investigation to assess whether longitudinal changes in organ Hounsfield units (HU) and total body gas volume (TBGV), as measured from serial PMCT scans, correlate with postmortem interval (PMI).: Eight euthanised lambs each had five whole body CT scans performed over seven days and measurements were taken from the brain, heart, lungs, liver, kidneys and spleen. HU tissue density was measured directly from the PMCT images, while TBGV was calculated using ImageJ software. A random effect model was fitted with the subject fitted as a random intercept. Ethical and Animal Welfare approval was obtained. : The average increase in TBGV was 422 ml/Kg with a change of 77 ml/Kg per day. For each additional post-mortem day, the HU of the brain, heart, lung, liver and spleen decreased by per day since death, while HU for the kidneys increased by day since death. Expect for the kidney where it increased, there was clear and progressive decrease in tissue densities and for all organs there was an increase in TBGV over time. However, the overlap in values between cases indicates that more work is required before either HU or TBGV can be developed as non-invasive methods to reliably determine time of death in humans.

Changes in 24-hour Urine Chemistry in Patients with Nephrolithiasis during Weight Loss with Glucagon-Like Peptide-1 Based Therapies

Background: Obesity is an independent risk factor for incident and recurrent nephrolithiasis. The impact of weight loss through glucagon-like peptide 1 (GLP-1) receptor agonists and dual GLP-1/ gastric inhibitory polypeptide receptor agonists (GLP-based therapies) on nephrolithiasis is not well-understood. This study examined the changes in 24-hour urine chemistry assessing for stone risk during weight loss through GLP-based therapies. Methods: This retrospective analysis identified adult stone formers followed at our academic institution’s weight wellness clinic between September 2015 and August 2023 and included patients with at least two 24-hour urine collections for stone risk assessment. 24-hour urine parameters before and during weight loss in patients on GLP-based therapies were compared. Results: Forty-four obese patients with nephrolithiasis experienced significant weight reduction (-6.6±7.3 kg, p&lt;0.001) over a median 1.1 years of follow-up with GLP-based therapies. During this period, there was a significant decrease in 24-hour urine oxalate (40±16 to 32±11 mg/day, p=0.002), sulfate (21±10 to 17±9 mmol/day, p=0005), and ammonium (35±22 to 29±15 mEq/day, p=0.01). There were non-significant changes in urine calcium, citrate, uric acid, pH, phosphorus, sodium, potassium, magnesium, chloride, creatinine or total volume. Additionally, there was no statistical difference in urine supersaturation indices with respect to calcium oxalate, calcium phosphate and uric acid. Conclusion: Our results indicate that weight loss through GLP-based therapies is not associated with pro-lithogenic changes in 24-hour urine chemistry in patients with nephrolithiasis, unlike what happens with other weight loss modalities.

Evaluating the Safety and effectivenesS in adult KorEaN patients treated with Tolvaptan for management of autosomal domInAnt poLycystic kidney disease (ESSENTIAL): final report.

Tolvaptan, a selective vasopressin V2 receptor antagonist, was first approved by the Korean Ministry of Food and Drug Safety in 2015 as a treatment option for autosomal dominant polycystic kidney disease (ADPKD). To prescribe tolvaptan safely and effectively, we designed the phase 4 clinical trial among Korean ADPKD patients with chronic kidney disease stages 1 to 3. A total of 117 Korean patients aged 19 to 50 years with rapidly progressing ADPKD were enrolled in the study. Tolvaptan was prescribed for 24 months with the maximum tolerable dose up to 120 mg/day. The primary outcome was the incidence of treatment-emergent adverse events (TEAEs) including hepatic adverse events. The secondary outcomes were the annual mean percent change of total kidney volume (TKV) and the annual mean change of estimated glomerular filtration rate (eGFR). A total of 489 TEAEs occurred in 106 patients (90.6%). A total of 17 cases of hepatic adverse events (14.5%) occurred during the study period and mostly within the first 18-month period. However, liver enzymes were normalized after drug discontinuation. Although it was not statistically significant, patients with a previous history of liver disease as well as those with mild elevation of liver enzyme showed a higher frequency of hepatic adverse events. Compared with the predicted value from the calculation, tolvaptan attenuated both TKV growth and eGFR decline rate. Although the incidence of hepatic adverse events was higher in Korean ADPKD patients compared to the previous studies, tolvaptan can be prescribed safely and effectively using meticulous titration and 1-month interval monitoring.

Progression of total training volume in resistance training studies and its application to skeletal muscle growth.

Progressive overload describes the gradual increase of stress placed on the body during exercise training, and is often quantified (i.e. in resistance training studies) through increases in total training volume (i.e. sets × repetitions × load) from the first to final week of the exercise training intervention. Within the literature, it has become increasingly common for authors to discuss skeletal muscle growth adaptations in the context of increases in total training volume (i.e. the magnitude progression in total training volume). The present manuscript discusses a physiological rationale for progressive overload and then explains why, in our opinion, quantifying the progression of total training volume within research investigations tells very little about muscle growth adaptations to resistance training. Our opinion is based on the following research findings: (1) a noncausal connection between increases in total training volume (i.e. progressively overloading the resistance exercise stimulus) and increases in skeletal muscle size; (2) similar changes in total training volume may not always produce similar increases in muscle size; and (3) the ability to exercise more and consequently amass larger increases in total training volume may not inherently produce more skeletal muscle growth. The methodology of quantifying changes in total training volume may therefore provide a means through which researchers can mathematically determine the total amount of external 'work' performed within a resistance training study. It may not, however, always explain muscle growth adaptations.

A Case of Good Efficacy of Tolvaptan in a Patient with Markedly Enlarged Polycystic Kidney

A 61-year-old patient with autosomal dominant polycystic kidney disease (Irazabal class 1E) in whom renal function had decreased and kidney size had increased over the past 3 years (change in serum creatinine, 1.3 mg/dL to 1.5 mg/dL; change in total kidney volume, 5632 cm3 to 7301 cm3) was treated with tolvaptan 60 mg/day. After 8 years of tolvaptan treatment, serum creatinine remained at 1.51 mg/dL, and total kidney volume was at 6812 cm3. Adequate salt intake and good weight control may have resulted in good outcomes, even in patients with treatment-resistant giant cystic kidney disease.

Recovery of muscular tissue and functional results of patients treated with a gluteus maximus flap transfer due to chronic abductor deficiency after total hip arthroplasty.

To evaluate the function of the abductor mechanism after a gluteus maximus flap transfer due to a degeneration of the muscles after hip arthroplasty, we analyzed the post-operative functional outcome as well as radiographic effects in muscle tissue. This present study included six consecutive patients operatively treated with a gluteus maximus flap due to chronic gluteal deficiency after total hip arthroplasty. All patients presented a preoperative severe limp, hip abductor deficiency and a history of conservative treatment without the relief of symptoms. MRI scans were performed pre- and postoperatively to evaluate the muscle volume and grade of degeneration of the abductor mechanism. For clinical evaluation, the Harris hip score (HHS) was applied pre- and postoperatively. Moreover, the intensity of pain, the Trendelenburg sign, the internal rotation lag sign and the abductor muscle force were measured before and after surgery. Overall, the evaluation of the Magnetic Resonance Imaging (MRI) showed no significant changes in total muscle volume during the follow-up period. Separate measurements presented a significant growth of muscle volume for the gluteus minimus and tensor fascia lata compared to preoperative imaging during the follow-up period. The amount of fat volume decreased for all the measured muscles with statistical significance for the gluteus minimus, the gluteus medius and the tensor fascia lata. No further muscle degeneration and no flap necrosis were measured. The postoperative HHS results were not statistically significant compared to the preoperative results. Besides fair clinical results, the radiological measurements indicate that the flap transfer enables functional muscular tissue recovery and prevents further degeneration. Given these conditions, the gluteus maximus muscle flap transfer represents a viable treatment option for patients with chronic gluteal deficiency in selected patients.

Long-term effectiveness and safety of tolvaptan in autosomal dominant polycystic kidney disease

Background and objectivesEvidence on the long-term use of tolvaptan in autosomal dominant polycystic kidney disease (ADPKD) is limited. The aim was to evaluate the tolvaptan effectiveness and safety in real clinical setting. Material and methodsA single-center observational study (2016–2022) involving ADPKD patients treated with tolvaptan was conducted. Annual change in serum creatinine (sCr) and estimated glomerular filtration rate (eGFR) before and after treatment initiation were evaluated. Change in total kidney volume (TKV), blood pressure (BP) and urinary albuminuria at 12, 24 and 36 months after initiation were also determined. Adverse events (AEs) according to the Common Terminology Criteria for Adverse Events (CTCAE) v5.0 were analyzed. ResultsA total of 22 patients were included. No significant differences pre- vs post tolvaptan treatment in annual rate of change in eGFR (−3.52ml/min/1.73m2 [−4.98%] vs −3.98ml/min/1.73m2 [−8.48%], p=0.121) and sCr (+0.06mg/dL [4.22%] vs +0.15mg/dL [7.77%], p=0.429) were observed. Tolvaptan improved urinary osmolality at 12 (p=0.019) and 24 months (p=0.008), but not at 36 months (p=0.11). There were no changes in TKV, BP control and urinary albuminuria at 12, 24 or 36 months. A worse response was shown in patients with rapid kidney function decline (p=0.042). A 36.4% of the patients developed grade III/IV AEs. A 22.7% discontinued treatment due to unacceptable toxicity. ConclusionsThis study shows a modest benefit of tolvaptan in ADPKD patients, as well as safety concerns.

The Disproportionate Impact of Primary Care Disruption and Telehealth Utilization During COVID-19.

The COVID-19 pandemic not only exacerbated existing disparities in health care in general but likely worsened disparities in access to primary care. Our objective was to quantify the nationwide decrease in primary care visits and increase in telehealth utilization during the pandemic and explore whether certain groups of patients were disproportionately affected. We used a geographically diverse primary care electronic health record data set to examine the following 3 outcomes: (1) change in total visit volume, (2) change in in-person visit volume, and (3) the telehealth conversion ratio defined as the number of pandemic telehealth visits divided by the total number of prepandemic visits. We assessed whether these outcomes were associated with patient characteristics including age, gender, race, ethnicity, comorbidities, rurality, and area-level social deprivation. Our primary sample included 1,652,871 patients from 408 practices. During the pandemic we observed decreases of 7% and 17% in total and in-person visit volume and a 10% telehealth conversion ratio. The greatest decreases in visit volume were observed among pediatric patients (-24%), Asian patients (-11%), and those with more comorbidities (-9%). Telehealth usage was greatest among Hispanic or Latino patients (17%) and those living in urban areas (12%). Decreases in primary care visit volume were partially offset by increasing telehealth use for all patients during the COVID-19 pandemic, but the magnitude of these changes varied significantly across all patient characteristics. These variations have implications not only for the long-term consequences of the COVID-19 pandemic, but also for planners seeking to ready the primary care delivery system for any future systematic disruptions.

Transjugular Intrahepatic Portosystemic Shunt Is Associated With Better Waitlist Management of Liver Transplant Candidates With Hepatocellular Carcinoma.

Transjugular intrahepatic portosystemic shunt (TIPS) reduces portal hypertension complications. Its impact on hepatocellular carcinoma (HCC) remains unclear. We evaluated 42,843 liver transplant candidates with HCC from the Scientific Registry of Transplant Recipients (2002-2022). 4,484 patients with and without TIPS were propensity score-matched 1:3. Analysing wait-list changes in total tumor volume, HCC count, and alpha-fetoprotein levels, and assessing survival from listing and transplantation; TIPS correlated with a decreased nodule count (-0.24 vs. 0.04, p = 0.028) over a median wait period of 284 days (IQR 195-493) and better overall survival from listing (95.6% vs. 91.5% at 1year, p < 0.0001). It was not associated with changes in tumor volume (0.28 vs. 0.11cm³/month, p = 0.58) and AFP (14.37 vs. 20.67ng/mL, p = 0.42). Post-transplant survival rates (91.8% vs. 91.7% at 1year, p = 0.25) and HCC recurrence (5.1% vs. 5.9% at 5 years, p = 0.14) were similar, with a median follow-up of 4.98 years (IQR 2.5-8.08). While TIPS was associated with a reduced nodule count and improved waitlist survival, it did not significantly impact HCC growth or aggressiveness. These findings suggest potential benefits of TIPS in HCC management, but further studies need to confirm TIPS safety.

Effect of supercritical carbon dioxide on pore structure and methane adsorption of shale with different particle sizes

Supercritical carbon dioxide (SCCO2) fracturing significantly enhances shale gas recovery, which is influenced by particle size. We soaked shale in SCCO2 and investigated the impact of SCCO2 on different particle sizes. Large-particle shales showed the largest percentage changes in specific surface area and total pore volume (54.11 %, 87.87 %; 58.59 %, 76.32 %) followed by small-particle size shales. This trend was also observed in other pore structure parameters. The particle-size effect is: Large-particle shale, with abundant microfractures, enhances SCCO2 flow and pore alteration. Small-particle shale's high specific surface area facilitates SCCO2 penetration. Medium-particle shale is less affected due to balanced interactions of these factors. Methane is primarily found in large and medium pores and microfractures. Methane adsorption in shale mainly involves multi-layer adsorption. Following SCCO2 treatment, pore fractures narrowed, increasing the proportion of methane molecules adsorbed as a single-layer. This study is crucial for evaluating the fracturing effects on shale gas wells.

Mapping geodetically inferred Antarctic ice surface height changes into thickness changes: a sensitivity study

Abstract. Determining recent Antarctic ice volume changes from satellite altimeter measurements of ice surface height requires a correction for contemporaneous vertical crustal deformation. This correction must consider two main sources of crustal deformation: (1) ongoing glacial isostatic adjustment (GIA), that is, the deformational, gravitational, and rotational response to Late Pleistocene and Holocene ice and ocean mass changes and (2) modern ice mass change. In this study, we seek to quantify the uncertainties associated with each of these corrections. Corrections of ice surface height changes for correction 1 have generally involved the adoption of global models of GIA defined by some preferred combination of ice history and mantle viscoelastic structure. We have computed the GIA correction generated from a coupled ice sheet–sea level model and a realistic Earth model incorporating three-dimensional viscoelastic structure. Integrating the difference between this correction and those from recent GIA analyses widely adopted in the literature yields an uncertainty in total present-day ice volume change equivalent to approximately 10 % of Antarctic ice mass loss inferred for the period 2010–2020. This reinforces earlier work indicating that ice histories characterized by relatively high excess ice volume at the Last Glacial Maximum may be introducing a significant error in estimates of modern melt rates. Regarding correction 2, a spatially invariant scaling has commonly been used to convert GIA-corrected ice surface height changes obtained from satellite altimetry to ice volume estimates. We adopt modeling results based on a projection of Antarctic ice mass change over the period 2015–2055 to demonstrate a spatial variability in the scaling of up to 10 % across the ice sheet. Furthermore, using these calculations, we find a systematic error of ∼ 3 % in the projected net ice volume change, with most of the difference arising in areas of West Antarctica above mantle zones of low viscosity.

Changes in tubular biomarkers with dietary intervention and metformin in patients with autosomal dominant polycystic kidney disease: a post-hoc analysis of two clinical trials

BackgroundTubular biomarkers, which reflect tubular dysfunction or injury, are associated with incident chronic kidney disease and kidney function decline. Several tubular biomarkers have also been implicated in the progression of autosomal dominant polycystic kidney disease (ADPKD). We evaluated changes in multiple tubular biomarkers in four groups of patients with ADPKD who participated in one of two clinical trials (metformin therapy and diet-induced weight loss), based on evidence suggesting that such interventions could reduce tubule injury.Methods66 participants (26 M/40 F) with ADPKD and an estimated glomerular filtration rate (eGFR) ≥ 30 ml/min/1.73m2 who participated in either a metformin clinical trial (n = 22 metformin; n = 23 placebo) or dietary weight loss study (n = 10 daily caloric restriction [DCR]; n = 11 intermittent fasting [IMF]) were included in assessments of urinary tubular biomarkers (kidney injury molecule-1 [KIM-1], fatty-acid binding protein [FABP], interleukin-18 [IL-18], monocyte chemoattractant protein-1 [MCP-1], neutrophil gelatinase-associated lipocalin [NGAL], clusterin, and human cartilage glycoprotein-40 [YKL-40]; normalized to urine creatinine), at baseline and 12 months. The association of baseline tubular biomarkers with both baseline and change in height-adjusted total kidney volume (HtTKV; percent change from baseline to 12 months) and estimated glomerular filtration rate (eGFR; absolute change at 12 months vs. baseline), with covariate adjustment, was also assessed using multiple linear regression.ResultsMean ± s.d. age was 48 ± 8 years, eGFR was 71 ± 16 ml/min/1.73m2, and baseline BMI was 30.5 ± 5.9 kg/m2. None of the tubular biomarkers changed with any intervention as compared to placebo. Additionally, baseline tubular biomarkers were not associated with either baseline or change in eGFR or HtTKV over 12 months, after adjustments for demographics, group assignment, and clinical characteristics.ConclusionsTubular biomarkers did not change with dietary-induced weight loss or metformin, nor did they associate with kidney disease progression, in this cohort of patients with ADPKD.

Evolution of in-situ pore structure of nanosilica modified high-volume blast furnace slag cementitious materials under sulfate attack

Nanosilica (NS) has been introduced to enhance the early strength and mitigate the porous structure issues associated with high-volume ground blast furnace slag (GGBS) cementitious materials (HVS). The impact of NS on the sulfate attack resistance in HVS cementitious materials is a noteworthy concern, especially concerning the degradation evolution process under sulfate attack. This study comprehensively analyzed the total volume changes and in-situ pore structure evolution for NS modified HVS cementitious materials under sulfate attack. The findings revealed that NS could effectively cause an increase in pores smaller than 100 nm and decrease in pores larger than 100 nm in HVS cementitious materials. Specifically, NS contributed to a reduction in volume expansion, weight loss, and surface damage of 80 wt% GGBS cement paste during sulfate attack. NS demonstrated its efficacy in improving the ability of 80 wt% GGBS cementitious materials to withstand expansion pressure caused by sulfate attack products, though NS did not significantly reduce the quantity of sulfate attack products. Conversely, NS led to an increase in volume expansion, weight loss and early damage of 60 wt% GGBS cement paste. The damage inflicted on cement paste under sulfate attack primarily manifested as the destruction of pores in nanometer. The process involved a cyclic sequence of pore filling, damage, refilling, and redamage during the sulfate attack process.

Construction of a bi-continuous charge transport network towards high-performance vanadium-based phosphate cathode materials for potassium ion batteries

As one class of most promising cathode materials for potassium ion batteries (KIBs), polyanionic compounds still suffer from unsatisfactory effective capacity and rate performance due to their poor intrinsic electronic conductivity. In this paper, nanoscale K3V3(PO4)4 (KVP) particles with a bi-continuous charge transport network (denote as KVP-S) are designed and prepared. Carbon nanotubes (CNTs) play a crucial role in this design, not only effectively inhibiting the aggregation and growth of particles, but also providing a three-dimensional (3D) electron conductive network. Benefiting from the advantages of nanoscale particle size and bi-continuous charge transport network, the KVP-S electrode exhibits a high capacity (118mAh g−1 at 20 mA g−1), outstanding rate performance (102 mAh g−1 at 0.5 C; 66 mAh g−1 at 5 C) and excellent cycling stability (94 % retention after 50 cycles at 1 C). Even at a higher rate of 5 C, it still maintains a high capacity retention of 92 % after 300 cycles. More importantly, the capacity can maintain 80 mAh g−1 at 1 C when the mass loading is extended to 4 mg cm−2, In addition, in-situ X-ray diffraction (XRD) and ex-situ X-ray photoelectron spectroscopy (XPS) analyses reveal that the potassium storage mechanism of KVP-S is two single-phase solid solution reactions, involving V2+/V3+/V4+ three-electron redox conversions with a total volume change of 5.5 %. This study provides a new way to rationally design nanoscale particle electrodes with highly conductive charge transport networks.