Cumulative Volume Research Articles

Deletion of Piezo2 from renal Foxd1+ stromal progenitors and descendent cells results in abnormal mesangial development and sex-specific differences in kidney function

Piezo2 is a mechanically activated ion channel recently identified in glomerular mesangial cells and renin+ juxtaglomerular (JG) cells. Despite several studies which confirm this localization of Piezo2 in the kidney, the function of Piezo2 in these cells remains ambiguous. In the current study, we hypothesized that loss of Piezo2 in mesangial and JG cells would result in abnormal glomerular development during nephrogenesis and impaired salt and water balance in adult mice. To test this hypothesis, we generated mutant mice lacking Piezo2 in Foxd1+ stromal progenitors and their cell lineages, which include mesangial and JG cells. Kidney morphology was assessed by immunofluorescent staining and z-stack confocal microscopy during late nephrogenesis (post-natal day 0, P0) and following maturation of the nephron (P20) in wild-type (Piezo2fl/fl, n=3), heterozygous (Foxd1GC/+Piezo2fl/+, n=3), and mutant (Foxd1GC/+Piezo2fl/fl, n=3) mice. In adult male and female mice (n=2/genotype/sex), blood pressure was measured by tail cuff (CODA Systems) between 1-4pm following 3 days of acclimation. In a separate group of control and mutant male and female mice (8-10 weeks, n=3-5/group/sex), a 4-hour saline challenge (i.p. 10% body weight) was performed to assess diuresis and natriuresis. At P0, we found that deletion of Piezo2 from Foxd1+ stromal progenitors and their cell lineages resulted in the abnormal distribution of mesangial cells within glomeruli, such that the mesangial area appears compressed compared to control or heterozygous mice. This phenotype was exacerbated in mutant mice by P20. In adult mice, female mutants had an increase in daytime mean arterial pressure (~10mmHg, mean 79 vs 88) compared to female controls. Cumulative urine excretion (4 hours, percent injected) was decreased in females compared to males, regardless of genotype (p<0.001). Further, female mutant mice had a delayed diuresis response compared to control (2 hour, mean 16% vs 28% cumulative urine volume). However by 4 hours following a saline bolus both groups were similar. Taken together, these data indicate that deletion of Piezo2 in Foxd1+ stromal progenitors results in impairments in mesangial cell development during nephrogenesis and alterations in water and salt balance in adult female mice. Understanding the sex-specific roles of Piezo2 in kidney development and physiology is critical to identify the role of mechanosensation on renal homeostasis. NIH R01DK121014 to LO. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Preliminary study on the mechanical behavior of clay in one-dimensional compression with DEM simulations

The mechanical behavior and physical properties of clay are closely associated with its microstructure. Current research on the macroscopic mechanics and physical properties of clay is comprehensive and systematic. However, the microstructural variations underlying these characteristics have been predominantly examined under mercury intrusion porosimetry and scanning electron microscopy, while quantitative and systematic studies are notably limited. This research employs the discrete element method (DEM) simulation to investigate the microscopic responses of clay, simulating one-dimensional compression tests on two clay types: card-house and book-house structures. The analysis of pore size and morphology was conducted using virtual mercury intrusion porosimetry and the pore segmentation method. The clay microstructure was quantitatively characterized by parameters such as pore aspect ratio, orientation distribution, and cumulative pore volume curve. The findings demonstrate that DEM effectively replicates the fundamental mechanical behavior of clay, revealing and explaining the evolution pattern of clay pore structure during one-dimensional compression in terms of platelet alignment adjustment. This macroscopic compression is characterized by variations in pore size distribution, orientation, and aspect ratio.

A two-dimensional model test system for floor failure during automatic roadway formation mining without pillars above confined water

The coal mining in North China is seriously threatened by floor water inrush from the Ordovician limestone, so it is particularly important to explore failure characteristics. Automatic roadway formation mining without pillars (ARFMP) provides an effective method for reducing floor failure. To explore failure characteristics above confined water, a two-dimensional model test system is built up. Such a system can be applied to compare the difference of floor failure between ARFMP above confined water and traditional retained coal pillar mining, and to intuitively analyze the lifting law of confined water under dynamic disturbance. The core features of this system include the customized spring sets and water bag adopted as materials to simulate the floor aquifer, the guide lift hose and branch conduit used as the lifting channel of confined water, and the flow rate and cumulative volume monitored in real time. The customized “cutting-support-blocking” integrated device is the key equipment to simulate ARFMP. Then, the model test is conducted on a typical engineering case. By comparing stress, displacement, and water inrush characteristics of floor in different areas, failure characteristics of the roof-cutting side, the middle of working face, the collapse column area, and the coal pillar side were obtained, and it was clarified that ARFMP can effectively prevent floor water inrush. According to the results of model test, a comprehensive treatment scheme combining ARFMP with the floor regional control is proposed to ensure the safe mining of working face.

Gold doped Wollastonite hybrid nanocomposites as a candidate for bone regeneration/healing applications: Biocompatibility and antimicrobial efficacy

This work investigates the bioactivity of pure Wollastonite and gold-doped Wollastonite nanohybrids synthesized via a wet chemical technique. Doping with gold nanoparticles at different ratios for Wollastonite, where a dramatic decrease in the respective average particle sizes at the lowest doping ratio of 1.25 wt./v%, then the particle size raised gradually with an increase in the content of gold nanoparticles. In addition, a significant increase in the calculated surface area and the cumulative pore volume upon incorporating gold nanoparticles with the lowest doping ratio of 1.25 wt./v% is associated with a slight decrease in the average pore size. Then, a gradual decrease in the calculated surface area and cumulative pore volume with the increase of doping ratio with gold nanoparticles is associated with an increase in average pore size. The results revealed that after two days of incubation for treated MG-63 cells, the W/Au 5 wt./v% showed the significantly highest alkaline phosphatase (ALP) activity among all other concentrations and the control cells. The ALP activity exceeded four mU/mL. After four days of incubation, the ALP activity in all doping ratios was significantly higher than the control cells, with no significant difference among other groups, but lower than ALP levels after two days of incubation. Also, pure Wollastonite and gold-doped Wollastonite nanohybrids, especially the lowest doping ratio of 1.25 wt./v%, have remarkable efficacy in combating E. coli (Gram-negative), S. aureus (Gram-positive) and Candida albicans. In vitro studies showed that pure Wollastonite and gold-doped Wollastonite nanohybrids had minimal cytotoxic effects on osteosarcoma MG-63 cells, while they showed remarkable cell proliferation even at low concentrations. Based on the in-vitro ALP, bioactivity and biocompatibility results, the content of ALP can directly reflect the activity or function of osteoblasts and is positively correlated with the mineralization ability of cells, which shows that pure and gold-doped Wollastonite nanohybrids were suitable candidates for bone regeneration/healing applications.

Stereotactic Radiosurgery for Patients with Brain Metastases from Hepatopancreaticobiliary Cancers.

The role of stereotactic radiosurgery (SRS) for patients with brain metastases from hepatopancreaticobiliary (HPB) cancers has yet to be established. The authors present a single-institution experience of patients with HPB cancers who underwent SRS when their cancer spread to the brain. We surveyed our Gamma Knife SRS data base of 18,000 patients for the years 1987-2022. In total, 19 metastatic HPB cancer patients (13 male) with 76 brain metastases were identified. The median age at SRS was 61 years (range: 48-83). The primary cancer sites were hepatocellular carcinoma (HCC, 11 patients), cholangiocarcinoma (CCC, 2 patients), and pancreatic carcinoma (PCC, 6 patients). The median Karnofsky Performance Score (KPS) was 80 (range: 50-90). Two patients underwent pre-SRS whole-brain fractionated radiation therapy (WBRT) and eight patients underwent pre-SRS surgical resection. All SRS was delivered in single session. The median margin dose was 18 Gy (range: 15-20). The median cumulative tumor volume was 8.1 cc (range: 1.0-44.2). The median patient overall survival (OS) after SRS was 7 months (range 1-79 months). Four patients had documented local tumor progression after SRS at a median time of 8.5 months (range: 2-15) between SRS and progression. Out of 76 treated tumors, 72 tumors exhibited local control. The local tumor control rate per patient was 78.9%. The local tumor control per tumor was 94.7%. Four patients developed new brain metastases at a median of 6.5 months (range: 2-17) after SRS. No patient experienced adverse radiation effects (AREs). At the last follow-up, 18 patients had died, all from systemic disease progression. Metastatic spread to the brain from HPB cancers occurs late in the course of the primary disease. In this study, all deceased patients ultimately died from primary disease progression. SRS is a non-invasive strategy that maximally preserves quality of life, and our results reported favorable outcomes compared to the existing literature. SRS should be considered as one of the primary management strategies for patients with brain metastatic spread from HPB cancer.

Cyclic Injection Leads to Larger and More Frequent Induced Earthquakes under Volume-Controlled Conditions

Abstract As carbon storage technologies advance globally, methods to understand and mitigate induced earthquakes become increasingly important. Although the physical processes that relate increased subsurface pore pressure changes to induced earthquakes have long been known, reliable methods to forecast and control induced seismic sequences remain elusive. Suggested reservoir engineering scenarios for mitigating induced earthquakes typically involve modulation of the injection rate. Some operators have implemented periodic shutdowns (i.e., effective cycling of injection rates) to allow reservoir pressures to equilibrate (e.g., Paradox Valley) or shut-in wells after the occurrence of an event of concern (e.g., Basel, Switzerland). Other proposed scenarios include altering injection rates, actively managing pressures through coproduction of fluids, and preinjection brine extraction. In this work, we use 3D physics-based earthquake simulations to understand the effects of different injection scenarios on induced earthquake rates, maximum event magnitudes, and postinjection seismicity. For comparability, the modeled injection considers the same cumulative volume over the project’s operational life but varies the schedule and rates of fluid injected. Simulation results show that cyclic injection leads to more frequent and larger events than constant injection. Furthermore, with intermittent injection scenario, a significant number of events are shown to occur during pauses in injection, and the seismicity rate remains elevated for longer into the postinjection phase compared to the constant injection scenario.

Alkali-silica reaction of ferronickel slag fine aggregate in Portland cement and alkali-activated slag mortars: Pessimum effect investigation

Ferronickel slag (FNS) with dense and hard nature exhibits great potential to be utilized as recycled aggregate in concrete production. This study investigated the alkali-silica reaction (ASR) and the pessimum proportion of FNS fine aggregate in Portland cement (PC) and alkali-activated ground granulated bast furnace slag (AAS) mortars as a substitute for river sand. Over a 120-day period, the accelerated mortar bar test revealed that the addition of FNS fine aggregate in both cases resulted in harmless ASR expansion. In PC mortars, the ASR expansion consistently decreased from 0.569 % to 0.114 % as the FNS content increased. In comparison, AAS mortars with higher pore solution alkalinity had the pessimum proportion of 30 % FNS. The ASR expansion values initially increased from 0.472 % to 0.554 % with an increase in FNS content from 0 % to 30 %, but then decreased to 0.146 % as the FNS content was further raised to 100 %. The amorphous ASR gel was identified as a hydrated alkali silicate gel and present within the existing veins in the river sand grain. The ASR reaction of FNS fine aggregate exhibited a self-mitigating effect on the deleterious expansion through its pessimum behavior. Additionally, the addition of FNS fine aggregate yielded a beneficial outcome by reducing the cumulative pore volume in the mortars, and thus enhanced the compressive strengths.

Rockburst early warning based on microseism and critical point theory

During the tunnel construction, rockbursts occurred, posing a risk to safety. To mitigate this risk, a microseismic monitoring system was installed in the tunnel to provide early warning of rockbursts. After conducting research on the evolution of microseismic events in terms of number, moment magnitude, and energy within a specific time frame, an approach for rockbursts risk assessment based on microseismic moment magnitude was proposed. The critical point theory was utilized to quantitatively analyze the energy release process of the surrounding rock before intense rockbursts. This analysis revealed that the energy release of the surrounding rock before rockbursts can be divided into three stages: stable energy release stage, transitional energy release stage and accelerated energy release stage. The obtained process, derived from the critical point theory, was compared and analyzed alongside the evolution process of value of b, cumulative apparent volume, and energy index.

Patient Interest in Quadriceps Autograft Anterior Cruciate Ligament Reconstruction Is Increasing Over Other Autograft Options: A 12-Year Google Trends Analysis

PurposeThe purpose of this study was to use Google trends to explore differences in public interest among types of anterior cruciate ligament (ACL) autografts, specifically quadriceps tendon, patellar tendon, and hamstring tendon autografts between 2008 and 2019. MethodsData were obtained by querying Google Trends for key terms and phrases for online search data ranging from January 2008 to December 2019. Relative search volumes were created based on searches related to anterior cruciate ligament reconstruction with comparative analysis generated for search terms related to quadriceps ACL, patellar tendon ACL, and hamstring ACL autografts. Statistical analysis included linear regression analysis, comparison of quarterly search volume trends over time, and comparison of cumulative annual search volumes for 2008 versus 2019. ResultsLinear models for respective search terms terms were statistically significant for the quadriceps (p<0.001) and patellar (p 0.007) tendon autograft groups, but not the hamstring group (p 0.129). The quadriceps autograft group demonstrated a 12-year search volume trend change of 0.56, which was significantly greater than the hamstring (0.07; p <0.001) and patellar tendon (0.168; p<0.001) groups. There was no significant difference in the trend change between hamstring and patellar tendon groups (p 0.20). Percent change in cumulative relative annual search volumes between 2008 and 2019 was 112% for the quadriceps tendon group, 12.9% for the hamstring group, and 18.6% for the patellar tendon group. ConclusionThis study indicates a consistently increasing public interest in quadriceps tendon autograft for ACL reconstruction. The quadriceps autograft group demonstrated a significantly greater 12-year online search volume trend, greater linear correlation, and larger percent change between 2008 and 2019 when compared to patellar tendon or hamstring autograft groups.

Efficient reuse of Sargassum spp. biomass and organic fraction of municipal solid waste by anaerobic co-digestion in the Dominican Republic: Evaluation of biochemical methanogenic potential and reaction rates

Anaerobic digestion (AD) is a potential solution to valorize invasive pelagic Sargassum spp. Sargassum spp. (SP) biomass is characterized by a low carbon/nitrogen (C/N) ratio, which, in addition to the presence of indigestible fiber, sulfide, salt, ash, and polyphenol content, are inhibitors to the AD process. Furthermore, its chemical composition depends on the season and region of harvesting. To increase biogas yields, biomass must be subjected to pre-treatment or an anaerobic co-digestion process with other waste biomass. In this paper results of co-digestion of Sargassum spp. and municipal solid waste (OFMSW) batches with different weight ratios are reported and compared with the mono-digestion of the two organic matrices. The objective is to provide an optimized SP to OFMSW ratio for the sustainable production of biogas in the Dominican Republic. Mono-digestion of Sargassum spp. showed the longest reaction time and the lowest biomethane yield as it lasted 30 days and provided a cumulative volume of biomethane equal to 79.68 NmLg−1VS. The addition of OFMSW led to the shortening of the reaction time to 10 days and to the increase of the yield and cumulative volume of biomethane. It can be attributed to the more favorable C/N ratio, to the presence of more readily digestible compounds and lower ash content of those batches. The reaction kinetics of all the investigated batches is properly fitted by the Modified Gompertz model. The system with a Sargassum spp.-OFMSW weight ratio of 33:67 allows to obtain a notable bio-methane volume of 327.27 ± 15.93 NmLg−1VS, ten times higher than from Sargassum spp. alone.

Quantification of daily workload, energy expenditure, and sleep of US Marine recruits throughout a 10-week boot camp.

During periods of high-volume vigorous exercise, United States Marine Corps recruits often experience musculoskeletal injuries. While the program of instruction (POI) for basic training is a defined training volume, the total workload of boot camp, including movements around the base, is unknown. The present study aimed to quantify the daily total workload, energy expenditure, and sleep during basic recruit training at Marine Corps Recruit Depot (MCRD) San Diego. Eighty-four male recruits from MCRD San Diego wore wrist wearable physiological monitors to capture their complete workload (mileage from steps), energy expenditure, and sleep throughout the 10-week boot camp. Marine recruits traveled an average of 11.5±3.4 miles per day (M±SD), expended 4105±823 kcal per day, and slept an average of 5 : 48±1 : 06 hours and minutes per night. While the POI designates a total of 46.3 miles of running and hiking, the actual daily average miles yielded approximately 657.6±107.2 miles over the 10-week boot camp. Recruit training requires high physical demand and time under tension due to the cumulative volume of movements around base in addition to the POI planned physical training.

The impact of surgical volume on outcomes in newly diagnosed colorectal cancer patients receiving definitive surgeries

Colorectal cancer (CRC) patients who receive cancer surgeries from higher-volume providers may have better outcomes. However, the definitions of surgical volume may affect the results. We aim to analyze the effects of different definitions of surgical volume on patient outcomes. We conducted a nationwide population-based study in Taiwan that enrolled all patients who underwent definitive surgery for newly diagnosed CRC. We used three common definitions of surgical volume: total volume means the total surgical number conducted by the same provider during the study period; cumulative volume was calculated as the number of operations the surgeon performed before the index procedure; annual volume was calculated as the number of times the surgeon had been responsible for surgery during the index year. In this study, we included 100,009 newly diagnosed CRC patients, including 55.8% males, of median age 66 years at diagnosis (range 20–105 years). After adjustment for the patient and provider characteristics, we found that CRC patients receiving definitive surgery by higher-volume providers had better outcomes, especially where surgeon volume may play a more important role than hospital volume. The cumulative volume could predict the 5-year mortality of the study cohort better than the total and annual volume.

Impact of sand to aggregate ratio on mechanical properties and micro-structures of waste crumb rubber concrete

The replacement of natural river sand with crumb rubber (CR) in crumb rubber concrete (CRC) has attracted attention for its remarkable toughness and environmentally friendly properties. Sand to aggregate ratio (SAR) needs special attention as an important parameter in the mix proportions design of CRC as the CR volume fraction will vary with the SAR, affecting the particle packing within the CRC and therefore having a significant impact on the CRC properties, such as workability, mechanical properties and micro-structures. Thus, present study discusses the impact of SAR on both fresh and hardened properties of CRC. Relationship between SAR and workability, strength (including compressive and flexural-tensile), dynamic elastic modulus and damping ratio are analyzed. Cumulative pore size distribution and micro-morphology for each mixture were assessed using mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) technology. Results show that the workability increases slightly and then decreases significantly with increasing SAR, and the best workability is demonstrated at a SAR of 40%. Wet packing density, compressive strength, and dynamic elastic modulus showed a monotonically decreasing trend with SAR from 30% to 70% due to the weaker bonding properties of the CR particles. Flexural-tensile strength and damping ratio exhibited an initial increase followed by a decrease with SAR, reaching peak values at 50%, measured at 9.75 MPa and 1.91%, respectively. Cumulative pore volume increased from 0.3244 to 0.4315 as SAR rose from 30% to 70%, potentially contributing to the decline in compressive strength and elastic modulus. Additionally, the micro morphology appeared to be more loose with the increase in SAR. Relationship between SAR and the above indicators is modelled. Radar charts were created to analyze the influence of SAR on the overall performance of CRC. The relative area shows a significant decrease when SAR exceeds 50%.

199 Gamma Knife Radiosurgery to Treat Neurofibromatosis Type 2-Associated Meningiomas: A 35 Year Experience and Paradigm for Future Treatment

INTRODUCTION: Management of neurofibromatosis type 2 (NF2)-associated meningiomas remains a case-by-case basis, and treatment options vary. METHODS: Forty-nine patients (22 male, 44.90%) with 213 NF2-associated meningiomas treated with SRS between 1987 and 2022 were retrospectively reviewed. The median age at SRS was 56 (range: 20-79) years. Twenty-nine (59.18%) patients had pre-SRS surgical resection, and 7 (14.29%) had prior radiotherapy. The median number of meningiomas per patient was 2 (range: 1-17), the median margin dose was 13 (range: 9-16) Gy, and the median cumulative tumor volume per patient was 8.30 (range: 0.10-74.26) cm3. RESULTS: Nine patients (18.37%) had local tumor progression. The 1- and 5-year local tumor control rates were 100% and 90.54%, respectively. Tumor volume &lt; 8.30 cm3 was associated with better local tumor control (p = 0.02, HR: 1.06, 95% CI: 1.01-1.12) on multivariate analysis. Twenty-five patients (51.02%) had detection of new growing tumors (DNGT). The 1- and 5-year DNGT rates were 78.05% and 47.38%, respectively. On multivariate analysis, &gt;2 meningiomas at SRS presentation per patient (p = 0.01, HR: 1.09, 95% CI: 1.02-1.17) was significantly associated with DNGT. Neurological symptoms improved in 20 patients (40.82%), remained stable in 28 patients (57.14%), and worsened in 1 (2.04%) patient at a median follow-up time of 81 (range: 6–267) months after SRS. Seventeen (34.69%) patients were deceased at last follow-up, and 4 patients expired due to intracranial disease progression. Two (4.08%) patients developed transient adverse radiation effects; no patients developed secondary malignancies. CONCLUSIONS: Single-session SRS can effectively be used to control tumor progression and improve neurological symptoms in NF2-associated meningioma patients while limiting adverse radiation effects.

1134 A Call to Revise the Thirty-year-old SRS Dose Guidelines for Brain Metastases

INTRODUCTION: Stereotactic Radiosurgery (SRS) currently is the most widely used neurosurgical strategy for treatment of brain metastases. Many centers still rely on 30-year-old dose volume guidelines derived from RTOG 90-05. METHODS: Between 2014 and 2020 330 NSCLC patients (median age = 65 years) with 2910 brain metastases underwent Gamma knife SRS. The number of tumors treated per patient ranged from 1-56 and the total tumor cumulative volume ranged from .05 to 33.09 cc (median = 3.17). The median prescribed tumor margin dose was 18 Gy. RESULTS: Median overall survival after radiosurgery was 15.5 months. Radiological tumor progression was noted 66 out of 2910 tumors (2.27%) in 51 out of 330 patients (15.45%). Tumors were divided into 4 categories based on tumor volumes (&lt;1.5 cc, 1.5-&lt;5 cc, 5-&lt;10 cc, and = 10cc). The effect of margin dose, and % tumor covered in 18 Gy, 20 Gy, and 24 Gy on local tumor control was analyzed for all 4 categories. In tumors with volumes &gt;1.5 cc local tumor control was significantly better (P &lt; 0.05) when =65% of the tumor volume received at least 24 Gy. No relationship was found between tumor control and 75, 90, and 100 % volumes receiving 18 or 20 Gy. CONCLUSIONS: In this study neither conformality of dose delivery nor tumor margin doses were the most important predictors of local tumor control as long as =65% of the tumor volume received at least 24 Gy. This finding can serve as a prescriptive guideline that allows margin doses below the RTOG guidelines, reduces reliance on strict conformality, and improves tumor control.

Evaluating the effect of geocell with vegetation and gravel on changes in the effective parameters of runoff using a rainfall simulator (case study: Iran)

Permeable pavements can reduce the negative effects of flooding in urban areas. This research seeks to study and compare the performance of the impervious surface as a control (O), sandy loam (SL), gravel (G), gravel with geocell layer (GGE), rosemary (R), rosemary with geocell layer (RRE), turf (T), and turf with geocell layer (TGE) in reducing runoff volume (RV), time to start runoff (TR), runoff coefficient (C), time to end runoff (TER), peak flowrate (PF), time to peak (TP), and time base (TB) under six different rainfall intensities (i) and two different slopes (s) using a rainfall simulator. For this purpose, 96 physical models were considered at the laboratory level. For the dependent variables TR, TER, PF, TP, and TB, there was a significant difference between the data at the level of 5% in all cases. Based on the results, changes in rainfall intensity, slope, and type of treatment could make a significant difference in the results of the C parameter. All treatments were able to reduce runoff volume in all test conditions. Rosemary had a better performance in controlling runoff and parameters affecting it compared to turf. The maximum and minimum cumulative runoff volumes observed for treatment GGE are 85.4 and 2 L, respectively. Finally, the results revealed that GGE could perform better in reducing runoff and cumulative volume in all cases compared to the rest of the test groups. The highest percentage of runoff volume reduction in GGE treatment was 96.5%.

Determination of Effective Radius under the Condition of Nonuniform Gas Occurrence and Borehole Plastic Failure.

In order to solve the problem of the blindness of borehole layout when the nonuniform occurrence of gas and the neglect of plastic failure around the borehole will underestimate the gas production, a gas-solid coupling model is established for considering plastic failure. The finite element software COMSOL Multiphysics is used to investigate the evolution of the effective radius during the nonuniform occurrence of gas, and the relationship between the effective radius and the borehole spacing is determined. The results show that the permeability around the borehole increases significantly when plastic failure is considered and the rising area is butterfly shaped, with a maximum increase of 94 times. Not only does the peak value of the gas drainage flow increase but the time of its occurrence is also delayed. The maximum gas drainage flow rate increases by 40.7%, and the cumulative drainage volume increases by 37%. The relationship between the effective radius and reasonable borehole spacing in nonuniform gas occurrence is obtained. This research can provide a reference for the selection of borehole spacing under the condition of nonuniform distribution of coal seam gas.

The influence of hospital volume and physician volume on early mortality in acute promyelocytic leukemia patients

Acute promyelocytic leukemia (APL) is a highly curable hematologic malignancy in the era of all-trans retinoic acid (ATRA) combination treatment. However, only a modest change in early mortality rate has been observed despite the wide availability of ATRA. In addition to the clinical characteristics of APL patients, studies on the hospital volume-outcome relationship and the physician volume-outcome relationship remained limited. We aim to evaluate the association between hospital and physician volume and the early mortality rate among APL patients. The patients were collected from Taiwan’s National Health Insurance Research Database (NHIRD). Early mortality is defined as death within 30 days of diagnosis. Patients were categorized into four groups according to individual cumulative hospital and physician volume. The risk of all-cause mortality in APL patients with different cumulative volume groups was compared using a Cox proportional hazard model. The probability of overall survival was estimated using the Kaplan–Meier method. All 741 patients were divided into four quartile volume groups. In the multivariate analysis, only physician volume was significantly associated with early mortality rate. The physician volume of the highest quartile was a protective factor for early mortality compared with the physician volume of the lowest quartile (HR 0.10, 95% CI 0.02–0.65). Hospital characteristics were not associated with early mortality. In the sensitivity analyses, the results remained consistent using two other different definitions of early mortality. Higher physician volume was independently associated with lower early mortality, while hospital volume was not. Enhancing the clinical expertise of low-volume physicians may ensure better outcomes.

Comparison of feldspar and meta-halloysite geopolymers by alkaline and acidic activation

Geopolymerization, a sustainable route to advanced binders, has traditionally been explored using common activators and single precursors such as metakaolin. Although previous investigations have explored the potential of feldspathic minerals, particularly with metakaolin as a partial replacement, there remains a gap in understanding the nuances of feldspar-phosphate-based geopolymers. This study seeks to fill this gap by providing an in-depth investigation of the properties and reactivity behaviour of three different feldspar quarry wastes, each modified with meta-halloysite at a 15% inclusion rate. This research not only evaluates the effects of both acidic and alkaline activators on the resulting geopolymer properties, but also explores the broader implications of such modifications in different environments at ambient conditions. Using a series of experimental assessments, we have explored how the mineralogical and crystalline identities of these feldspars influence key aspects such as reaction kinetics, physico-mechanical performance, structural and microstructural properties, and even thermal behaviour. The results of the physico-mechanical properties showed that lower water absorption (i.e. less than 9.2%) as well as higher flexural (i.e. about 30 MPa) and compressive strength (i.e. about 40 MPa) can be achieved with the feldspar-based geopolymer in alkaline medium. In acidic medium, the highest flexural and compressive strengths were less than 10 and 19 MPa, respectively, with about 13.5% of water absorption. In acidic to basic medium, the highest cumulative pore volume of the geopolymers increases from 26.5 to 75.2 mm3/g, respectively. The outcomes of this study hold promise for tailoring geopolymer properties for various applications and provide a basis for further work in this area.

Dynamics of the 2021 unrest at Changbaishan Tianchi volcano from ALOS-2/PALSAR-2 and seismic data

The Changbaishan Tianchi intraplate volcano is one of the most active and hazardous volcanoes of NE Asia, characterized by a summit caldera formed after the 946 CE ‘Millennium’ Plinian eruption. From December 2020 to June 2021, the frequency and magnitude of earthquakes at Tianchi were significantly higher than during background periods, with hundreds of earthquakes (46 events per month in average) and reaching a local magnitude of ML 3.1. This study reports a comprehensive deformation analysis and geophysical inversion scheme aimed to unveil the dynamics of this period. Multi-temporal InSAR analysis results of 32 ALOS-2 images from 2018 to 2022 show that the surface deformation is a combination of seasonal fluctuations (± 25 mm in average, with a maximum ± 45 mm) and a long-term positive component. The least squares linear regression of the deformation time series and temperature data, isolates the seasonal fluctuations, revealing a clear uplift-subsidence process from June 2020 to July 2021 in the caldera area. To constrain the Tianchi plumbing system dynamics, a combined inversion scheme consisting of three deformation sources is designed. The inversion results and the seismic records indicate that Tianchi volcano has experienced a low-level unrest episode from December 2020 to June 2021. The shallower plumbing system, located at about 5–9 km depth and modelled by pressurized spheroids, underwent a cumulative volume increase of 26 × 106 m3 from November 2018 to April 2021, followed by a volume decrease of 9 × 106 m3 from April to July 2021. This suggests magma uprising from the 14 km deep storage zone to the shallower plumbing system, followed by depressurization of the plumbing system due to the escape of fluids. This research provides a comprehensive understanding of the magma and fluid migration dynamics within the Tianchi multi-level plumbing system for the first time.