Repairing distorted hologram data for sound field reconstruction.

This paper proposes a distorted hologram data repair approach for sound field reconstruction. In this approach, an equivalent source model is established by placing a set of equivalent sources near the hologram surface to represent the measured hologram pressures. Each hologram pressure is simultaneously assigned an indicator to describe whether its measurement is corrupted by errors or not. This model is then formulated within a modal framework by utilizing the modes generated through the singular value decomposition of the transfer matrix between the hologram and nearby equivalent source surfaces. Subsequently, the indicators and modal coefficients are assigned the 0-1 and Gaussian prior distributions, respectively, and their posterior distributions are derived using the Bayesian method. The means of the posterior distributions are calculated to discriminate corrupted measurements and repair distorted hologram pressures. Repaired hologram pressures are finally utilized for reconstructions using the equivalent source method. Results from both numerical simulations conducted under various parameter settings and two experiments demonstrate the effectiveness of the proposed approach in automatically discriminating all the corrupted measurements and accurately repairing the distorted hologram pressures. Furthermore, the accuracy of the reconstructions using the repaired hologram pressures is comparable to that achieved with the correctly measured pressures.

Real-time nearfield acoustic holography using particle velocity.

In this paper, a series of impulse response functions between acoustic quantities on the source plane and particle velocity on the hologram plane are derived. In virtue of these functions, real-time nearfield acoustic holography (RT-NAH) is extended from pressure-based to particle velocity. Pressure, normal velocity, acceleration, and displacement radiated from planar sources can be reconstructed by measuring time-dependent particle velocity signals on the hologram plane. A simulation of an excited aluminum plate is performed to evaluate the difference in accuracy between RT-NAHs based on pressure and based on particle velocity. This study also examines the impact of impulse response functions on the reconstruction results, allowing for detailed analysis of the reconstruction accuracy based on these functions. The simulation results demonstrate that using RT-NAH based on particle velocity obtains significantly higher-accuracy reconstruction results when reconstructing normal velocity and displacement and slightly more accurate reconstructed pressure and normal acceleration.

The safety and efficacy of neoadjuvant immunochemotherapy following laparoscopic gastrectomy for gastric cancer: a multicenter Real-world clinical study.

BACKGROUND: The safety and efficacy of neoadjuvant immunochemotherapy (nICT) for locally advanced gastric cancer (LAGC) remain controversial. METHODS: Patients with LAGC who received either nICT or neoadjuvant chemotherapy (nCT) at 3 tertiary referral teaching hospitals in China between January 2016 and October 2022 were analysed. After propensity-score matching (PSM), comparing the radiological response, pathological response rate, perioperative outcomes, and early recurrence between the two groups. RESULTS: After PSM, 585 patients were included, with 195 and 390 patients comprising the nICT and nCT groups, respectively. The nICT group exhibited a higher objective response rate (79.5% versus [vs.] 59.0%; P<0.001), pathological complete response rate (14.36% vs. 6.41%; P=0.002) and major pathological response rate (39.49% vs. 26.15%; P=0.001) compared with the nCT group. The incidence of surgical complications (17.44% vs. 16.15%, P=0.694) and proportion of perioperative textbook outcomes (80.0% vs. 81.0%; P=0.767) were similar in both groups. The nICT group had a significantly lower proportion of early recurrence than the nCT group (29.7% vs. 40.8%; P=0.047). Furthermore, the multivariable logistic analysis revealed that immunotherapy was an independent protective factor against early recurrence (odds ratio 0.62 [95% CI 0.41-0.92]; P=0.018). No significant difference was found in neoadjuvant therapy drug toxicity between the two groups (51.79% vs. 45.38%; P=0.143). CONCLUSIONS: Compared with nCT, nICT is safe and effective, which significantly enhanced objective and pathological response rates, and reduced the risk for early recurrence among patients with LAGC. TRIAL REGISTRATION: Clinical Trials.gov.

Non-invasive imaging for predicting labial salivary gland biopsy outcomes in patients with suspected primary Sjögren syndrome.

To identify the value of salivary gland ultrasound (SGUS) combined with magnetic resonance imaging (MRI) and magnetic resonance sialography (MRS) in predicting the results of labial salivary gland biopsy (LSGB) in patients with suspected primary Sjögren syndrome (pSS), and construct a nomogram model to predict LSGB results. A total of 181 patients who were admitted with suspected pSS from December 2018 to April 2023 were examined and divided into a training set (n = 120) and a validation set (n = 61). Baseline data of the two groups were examined, and the value of SGUS, MRI, and MRS in predicting LSGB was analyzed. Multivariate logistic analysis was used to screen for risk factors, and nomogram prediction models were constructed using these results. In the training set, the SGUS, MRI, and MRS scores of patients in the LSGB + group were higher than those in the LSGB - group (all P < 0.001). The positive prediction value (PPV) was 91% for an SGUS score of 3, and 82% for MRI and MRS scores of 2 or more. We developed a nomogram prediction model based on SGUS, MRI, and MRS data, and it had a concordance index (C-index) of 0.94. The Hosmer-Lemeshow test (χ2 = 3.17, P = 0.92) also indicated the nomogram prediction model had good accuracy and calibration for prediction of LSGB results. A nomogram model based on SGUS, MRI, and MRS results can help rheumatologists decide whether LSGB should be performed in patients with suspected pSS.

Effects of visceral adipose tissue on anti-tumour necrosis factor-α in Crohn's disease.

Background: It remains unclear whether visceral adipose tissue (VAT) can predict the response of patients with Crohn's disease (CD) to anti-tumour necrosis factor-α (anti-TNF-α) therapy. Objectives: This study aimed to investigate whether VAT predicts the efficacy of infliximab (IFX) for different sites of CD and its relationship with serum TNF-α levels and IFX serum trough concentration. Design: This is a multicentre retrospective study. Methods: Patients with CD treated with IFX from January 2014 to January 2021 were included. The perimeter of the visceral adipose area was obtained by a Computed Tomography (CT) scan. Participants were classified according to the lesion site (L1, L2, and L3) and visceral fat area. The participants were divided into colon-uninvolved non-visceral obesity (L1-VATL), colon-uninvolved visceral obesity (L1-VATH), colon-involved non-visceral obesity (L2 + L3-VATL), and colon involved visceral obesity (L2 + L3-VATH) groups. The end points of this study were set as disease remission status at 6 and 12 months. Results: The final cohort included 140 patients. Regarding efficacy at 6 and 12 months, there was a significant difference between L1-VATL (73.8% versus 36.8%, p = 0.006) and L1-VATH (81.0% versus 47.4%, p = 0.008) groups. In the analysis of serum TNF-α levels and IFX serum trough concentrations, there was a significant difference between L1-VATL and L1-VATH (59.5 pg/mL versus 236.0 pg/mL, pTNF-α = 0.006), (10.0 µg/mL versus 0.4 µg/mL, pIFX = 0.000), and L1-VATH and L2 + L3-VATH (78.7 pg/mL versus 118.6 pg/mL, pTNF-α = 0.031), (0.4 µg/mL versus 6.40 µg/mL, pIFX = 0.017). Conclusion: In L1 patients, the VAT level predicted the efficacy of IFX, with high VAT values indicating poor efficacy. The VAT level may be a useful radiological marker to predict the efficacy of IFX in patients with various types of CD.

A near-infrared fluorescent probe for in situ imaging of SO2 flux in drug-induced liver injury.

Sulfur dioxide (SO2) has been widely applied as an important additive in various foods and drugs due to its antioxidant, antiseptic and bleaching properties. SO2 in living organisms plays a key biological role as an antioxidant in a variety of life activities. However, abnormal levels of SO2 in both food and living organisms could cause harm and even serious illness, such as diseases related to the respiratory and cardiovascular systems and cancers. Therefore, it is of great practical significance to accurately determine the level of SO2 in food and organisms. In this work, we synthesized a novel near-infrared ratiometric fluorescent probe (NTO) using xanthene and benzopyran as the matrix for the detection of SO2. NTO demonstrates a rapid response (within 8 s), high selectivity, excellent sensitivity (LOD = 3.64 µM) and a long emission wavelength (800 nm), which could be applied to SO2 monitoring in a complex environment. NTO showed a high recovery (90%-110%) of SO2 in food samples such as beer and rock sugar. The results of HeLa cell experiments indicate that NTO has excellent fluorescence labeling ability for SO2 in endoexogenous-sulfide metabolism. In addition, we applied it to mice with acetaminophen (APAP)-induced acute liver injury and observed changes in SO2 during liver injury. Based on these results, we believe that this will provide a convenient visual tool for the detection of the SO2 content in food safety and biomedicine.

The causal effects of age at menarche, age at first live birth, and estradiol levels on systemic lupus erythematosus: A two-sample Mendelian randomization analysis.

OBJECTIVES: To determine whether age at menarche (AAM), age at first live birth (AFB), and estradiol levels are causally correlated with the development of systemic lupus erythematosus (SLE). METHODS: A two-sample Mendelian randomization (MR) analysis was performed after data was collected from a dataset of genome-wide association studies (GWASs) related to SLE (as outcome), and from open access databases to find statistics related to AAM, AFB, and estradiol levels (as exposure). RESULT: In our study, a negative causal correlation between AAM and SLE was confirmed by MR analysis (MR egger: beta = 0.116, SE = 0.948, p = 0.909; weighted median: beta = -0.416, SE = 0.192, p = 0.030; and IVW: beta = -0.395, SE = 0.165, p = 0.016). However, there were no genetic causal effects of AFB and the estradiol levels on SLE, based on the results of MR analysis as follows: AFB (MR egger: beta = - 2.815, SE = 1.469, p = 0.065; Weighted median: beta = 0.334, SE = 0.378, p = 0.377; and IVW: beta = 0.188, SE = 0.282, p = 0.505) and the estradiol levels (MR egger: beta = 0.139, SE = 0.294, p = 0.651; weighted median: beta = 0.063, SE = 0.108, p = 0.559; IVW: beta = 0.126, SE = 0.097, p = 0.192). CONCLUSIONS: Our findings revealed that AAM may be associated with increased risk of the development of SLE, while there were no such causal effects from AFB and estradiol levels.

Absolute dosimetry for FLASH proton pencil beam scanning radiotherapy.

A paradigm shift is occurring in clinical oncology exploiting the recent discovery that short pulses of ultra-high dose rate (UHDR) radiation-FLASH radiotherapy-can significantly spare healthy tissues whilst still being at least as effective in curing cancer as radiotherapy at conventional dose rates. These properties promise reduced post-treatment complications, whilst improving patient access to proton beam radiotherapy and reducing costs. However, accurate dosimetry at UHDR is extremely complicated. This work presents measurements performed with a primary-standard proton calorimeter and derivation of the required correction factors needed to determine absolute dose for FLASH proton beam radiotherapy with an uncertainty of 0.9% (1[Formula: see text]), in line with that of conventional treatments. The establishment of a primary standard for FLASH proton radiotherapy improves accuracy and consistency of the dose delivered and is crucial for the safe implementation of clinical trials, and beyond, for this new treatment modality.

Proton FLASH Radiotherapy for the Treatment of Symptomatic Bone Metastases: The FAST-01 Nonrandomized Trial.

Importance: To our knowledge, there have been no clinical trials of ultra-high-dose-rate radiotherapy delivered at more than 40 Gy/sec, known as FLASH therapy, nor first-in-human use of proton FLASH. Objectives: To assess the clinical workflow feasibility and treatment-related toxic effects of FLASH and pain relief at the treatment sites. Design, Setting, and Participants: In the FAST-01 nonrandomized trial, participants treated at Cincinnati Children's/UC Health Proton Therapy Center underwent palliative FLASH radiotherapy to extremity bone metastases. Patients 18 years and older with 1 to 3 painful extremity bone metastases and life expectancies of 2 months or more were eligible. Patients were excluded if they had foot, hand, and wrist metastases; metastases locally treated in the 2 weeks prior; metal implants in the treatment field; known enhanced tissue radiosensitivity; and implanted devices at risk of malfunction with radiotherapy. One of 11 patients who consented was excluded based on eligibility. The end points were evaluated at 3 months posttreatment, and patients were followed up through death or loss to follow-up for toxic effects and pain assessments. Of the 10 included patients, 2 died after the 2-month follow-up but before the 3-month follow-up; 8 participants completed the 3-month evaluation. Data were collected from November 3, 2020, to January 28, 2022, and analyzed from January 28, 2022, to September 1, 2022. Interventions: Bone metastases were treated on a FLASH-enabled (≥40 Gy/sec) proton radiotherapy system using a single-transmission proton beam. This is consistent with standard of care using the same prescription (8 Gy in a single fraction) but on a conventional-dose-rate (approximately 0.03 Gy/sec) photon radiotherapy system. Main Outcome and Measures: Main outcomes included patient time on the treatment couch, device-related treatment delays, adverse events related to FLASH, patient-reported pain scores, and analgesic use. Results: A total of 10 patients (age range, 27-81 years [median age, 63 years]; 5 [50%] male) underwent FLASH radiotherapy at 12 metastatic sites. There were no FLASH-related technical issues or delays. The average (range) time on the treatment couch was 18.9 (11-33) minutes per patient and 15.8 (11-22) minutes per treatment site. Median (range) follow-up was 4.8 (2.3-13.0) months. Adverse events were mild and consistent with conventional radiotherapy. Transient pain flares occurred in 4 of the 12 treated sites (33%). In 8 of the 12 sites (67%) patients reported pain relief, and in 6 of the 12 sites (50%) patients reported a complete response (no pain). Conclusions and Relevance: In this nonrandomized trial, clinical workflow metrics, treatment efficacy, and safety data demonstrated that ultra-high-dose-rate proton FLASH radiotherapy was clinically feasible. The treatment efficacy and the profile of adverse events were comparable with those of standard-of-care radiotherapy. These findings support the further exploration of FLASH radiotherapy in patients with cancer. Trial Registration: ClinicalTrials.gov Identifier: NCT04592887.

Value of magnetic resonance imaging and sialography of the parotid gland for diagnosis of primary Sjögren syndrome.

AIM: To evaluate the utility of magnetic resonance imaging (MRI) and magnetic resonance sialography (MRS) for diagnosis of primary Sjögren syndrome (pSS) singly or integrated with 2016 American College of Rheumatology (ACR)/European League Against Rheumatic Diseases (EULAR) classification criteria. METHODS: The diagnostic efficiencies of MRI, MRS, and labial salivary gland biopsy (LSGB) were evaluated. The prediction model was established by multivariate analysis. Finally, performance of the ACR/EULAR criteria was evaluated after addition of MRI + MRS or replacement of original items by MRI + MRS. RESULTS: The combined use of LSGB + MRI + MRS provided the greatest diagnostic value. MRI and MRS grade had positive correlations with disease duration and pathological grade of the labial gland (both P < 0.001). MRI and MRS grade had positive correlations with xerostomia severity and negative correlations with unstimulated salivary flow rate (both P < 0.001). The consistency of MRI grade and MRS grade in the diagnosis of parotid gland lesions was poor (κ = 0.253, P < 0.001). The diagnostic efficiency of our prediction model (AUC 0.906) was similar to that of criteria from the ACR/EULAR (AUC 0.930). Adding MRI + MRS to the ACR/EULAR criteria improved the sensitivity (92.3% vs 90.8%), whereas the specificity remained the same (88.9% vs 89.1%). Replacing LSGB by MRI + MRS in the ACR/EULAR criteria decreased both sensitivity and specificity (88.1% vs 90.8% and 86.4% vs 89.1%, respectively). CONCLUSION: The combined application of MRI and MRS has ideal clinical application value in the diagnosis of early-stage pSS. Validity of the ACR/EULAR criteria remains high after incorporation of MRI + MRS.

Viscosity-sensitive NIR probe for in vivo imaging of early-stage hepatic fibrosis.

Herein, a viscosity-sensitive and hepatic-targeted NIR fluorescent probe has been developed for early diagnosis of hepatic fibrosis. Importantly, we observed increased liver viscosity upon CCl4-induced hepatotoxicity and decreased liver viscosity after metformin treatment, which confirmed its high clinical application prospects.

Evaluation of a conventionally shielded proton treatment room for FLASH radiotherapy.

PURPOSE: FLASH radiotherapy (FLASH-RT) is the potential for a major breakthrough in cancer care, as preclinical results have shown significantly reduced toxicities to healthy tissues while maintaining excellent tumor control. However, FLASH conditions were not considered in the current proton facilities' shielding designs. The purpose of this study is to validate the adequacy of conventionally shielded proton rooms used for FLASH-RT. METHODS: Clinical FLASH irradiations typically take place in a few 100 ms, orders of magnitude shorter than the response time of the wide-energy neutron detector (WENDI-II). The nozzle beam current (representing the dose rate) dependence of the WENDI-II detector response was empirically determined to stabilize with a beam current of ≤10 nA at the measurement point with the highest dose rate. A large, predefined proton transmission FLASH plan (250 MeV, 7 × 20 cm2 , 8 Gy at isocenter) was commissioned as part of a FLASH clinical trial. For purpose of this study, that field was adjusted from 250 to 244 MeV, allowing a lower beam current of 10 nA to provide reliable detector response. Radiation surveys were performed for the proton beams with/without extra beam stopper (30 × 30 × 40-cm3 solid water slabs) at 0°, 90°, 180°, and 270° gantry angles. RESULTS: Ambient doses were recorded at seven different locations. A 170-nA beam current, commonly used for clinical FLASH plans, was chosen to normalize the average ambient dose rate to FLASH conditions. Assuming 200-Gy/h workload (25 FLASH beams, 8 Gy/beam), annual occupational dose at controlled areas was calculated. For all gantry angles, ≤0.4 mSv/year is expected at treatment room door. The highest ambient dose, 2.46 mSv/year, ∼5% of the maximum annual permissible occupational dose, was identified at the isocenter of the adjacent treatment room with 90° gantry. CONCLUSION: These survey results indicate that our conventionally shielded proton rotating gantry rooms result in acceptable occupational and public doses when the transmission FLASH beams delivered at four cardinal gantry angles based on 200-Gy/h workload assumption. These findings support that FLASH clinical trials in our conventionally shielded proton facilities can be safely implemented.

A tracer-type fluorescent probe for imaging adenosine triphosphate under the stresses of hydrogen sulfide and hydrogen peroxide in living cells.

Adenosine triphosphate (ATP) is a direct energy source in cells and the core of the biochemical system, and is closely related to various metabolic activities in living organisms. Therefore, designing a simple and rapid ATP detection method is significant to study its physiological function. Herein, a dual-channel fluorescent probe RhB-NA for the in situ imaging of ATP in living cells was designed and synthesized. When ATP bound to RhB-NA, the spirolactam in rhodamine B was induced to open, resulting in a new fluorescence response at 589 nm. Notably, in cell imaging, the treatment of HeLa cells with exogenous H2O2 and H2S, which have certain effects on the mitochondria, confirmed that RhB-NA could detect fluctuations in ATP levels after the mitochondrial state was affected. We believe that RhB-NA has far-reaching significance for studying certain physiological diseases caused by abnormal ATP levels.

Biological roles of sulfur dioxide and sulfite in the regulation of mitochondrial viscosity.

Herein, a NIR fluorescent probe has been developed for visualization of the roles of SO2/SO32- in mitochondrial viscosity. The results showed that SO32- would increase mitochondrial viscosity and decrease mitochondrial membrane potential (MMP). However, increasing SO2 stimulation decreased mitochondrial viscosity and caused inconspicuous MMP changes.

Enzyme-activated prodrugs and their release mechanisms for the treatment of cancer.

Enzyme-activated prodrugs have received a lot of attention in recent years. These prodrugs have low toxicity to cells before they are activated; when they interact with specific enzymes, they can effectively release anticancer drugs, thereby achieving the effect of treating cancer. At the same time, compared with other thiol-activated prodrugs, reactive oxygen species-activated prodrugs, and acid-activated prodrugs, the specificity of enzyme-activated prodrugs is stronger; therefore, these prodrugs have greater development potential. In this review, we summarize the different release mechanisms of prodrugs on the basis of enzyme-activated prodrugs, such as enzyme reduction, enzymatic hydrolysis, enzyme-activated and light-radiation-assisted release, and enzymatic-activated and nanoparticle-assisted release mechanisms. A profound understanding of these release mechanisms will contribute to the design of enzyme-activated prodrugs.

Land Use and Climate Change Altered the Ecological Quality in the Luanhe River Basin.

Monitoring and assessing ecological quality (EQ) can help to understand the status and dynamics of the local ecosystem. Moreover, land use and climate change increase uncertainty in the ecosystem. The Luanhe River Basin (LHRB) is critical to the ecological security of the Beijing-Tianjin-Hebei region. To support ecosystem protection in the LHRB, we evaluated the EQ from 2001 to 2020 based on the Remote Sensing Ecological Index (RSEI) with the Google Earth Engine (GEE). Then, we introduced the coefficient of variation, Theil-Sen analysis, and Mann-Kendall test to quantify the variation and trend of the EQ. The results showed that the EQ in LHRB was relatively good, with 61.08% of the basin rated as 'good' or 'excellent'. The spatial distribution of EQ was low in the north and high in the middle, with strong improvement in the north and serious degradation in the south. The average EQ ranged from 0.58 to 0.64, showing a significant increasing trend. Furthermore, we found that the expansion of construction land has caused degradation of the EQ, whereas climate change likely improved the EQ in the upper and middle reaches of the LHRB. The results could help in understanding the state and trend of the eco-environment in the LHRB and support decision-making in land-use management and climate change.

Ultrahigh dose rate pencil beam scanning proton dosimetry using ion chambers and a calorimeter in support of first in-human FLASH clinical trial.

PURPOSE: To provide ultrahigh dose rate (UHDR) pencil beam scanning (PBS) proton dosimetry comparison of clinically used plane-parallel ion chambers, PTW (Physikalisch-Technische Werkstaetten) Advanced Markus and IBA (Ion Beam Application) PPC05, with a proton graphite calorimeter in a support of first in-human proton FLASH clinical trial. METHODS: Absolute dose measurement intercomparison of the plane-parallel plate ion chambers and the proton graphite calorimeter was performed at 5-cm water-equivalent depth using rectangular 250-MeV single-layer treatment plans designed for the first in-human FLASH clinical trial. The dose rate for each field was designed to remain above 60 Gy/s. The ion recombination effects of the plane-parallel plate ion chambers at various bias voltages were also investigated in the range of dose rates between 5 and 60 Gy/s. Two independent model-based extrapolation methods were used to calculate the ion recombination correction factors ks to compare with the two-voltage technique from most widely used clinical protocols. RESULTS: The mean measured dose to water with the proton graphite calorimeter across all the predefined fields is 7.702 ± 0.037 Gy. The average ratio over the predefined fields of the PTW Advanced Markus chamber dose to the calorimeter reference dose is 1.002 ± 0.007, whereas the IBA PPC05 chamber shows ∼3% higher reading of 1.033 ± 0.007. The relative differences in the ks values determined from between the linear and quadratic extrapolation methods and the two-voltage technique for the PTW Advanced Markus chamber are not statistically significant, and the trends of dose rate dependence are similar. The IBA PPC05 shows a flat response in terms of ion recombination effects based on the ks values calculated using the two-voltage technique. Differences in ks values for the PPC05 between the two-voltage technique and other model-based extrapolation methods are not statistically significant at FLASH dose rates. Some of the ks values for the PPC05 that were extrapolated from the three-voltage linear method and the semiempirical model were reported less than unity possibly due to the charge multiplication effect, which was negligible compared to the volume recombination effect in FLASH dose rates. CONCLUSIONS: The absolute dose measurements of both PTW Advanced Markus and IBA PPC05 chambers are in a good agreement with the National Physical Laboratory graphite calorimeter reference dose considering overall uncertainties. Both ion chambers also demonstrate good reproducibility as well as stability as reference dosimeters in UHDR PBS proton radiotherapy. The dose rate dependency of the ion recombination effects of both ion chambers in cyclotron generated PBS proton beams is acceptable and therefore, both chambers are suitable to use in clinical practice for the range of dose rates between 5 and 60 Gy/s.

Dual-channel detection of viscosity and pH with a near-infrared fluorescent probe for cancer visualization.

Compared to ordinary cells, tumor cells have a unique microenvironment, characterized by high viscosity, low pH, high reactive oxygen species level and the overexpression of certain proteases. Therefore, viscosity and pH can be used as important parameters for visualizing cancer. We designed a spiro-oxazolidine compound (In-1) for the dual-channel detection of viscosity and pH, with the red channel for detecting viscosity and the blue channel for pH. Interestingly, In-1 can locate different organelles under different conditions. Under physiological conditions, In-1 efficiently targeted lysosomes and showed that the viscosity of lysosomes increases in cancer cells while the pH decreases, which can be used to distinguish and detect cancer cells and normal cells. When we treated HL-7702 cells with CCCP, the probe could effectively target the mitochondria, and the fluorescence intensity in the pH channel decreased. This indicates that In-1 can be used as a powerful tool to simultaneously monitor viscosity and pH in different organelles, and may have a guiding role in diseases caused by mitochondrial and lysosomal microenvironments.

Sound field reconstruction using block sparse Bayesian learning equivalent source method.

Nearfield acoustic holography based on the compressed sensing theory can realize the accurate reconstruction of sound fields with fewer measurement points on the premise that an appropriate sparse basis is obtained. However, for different types of sound sources, the appropriate sparse bases are diverse and should be constructed elaborately. In this paper, a block sparse Bayesian learning (SBL) equivalent source method is proposed for realizing the reconstruction of the sound fields radiated by different types of sources, including the spatially sparse sources, the spatially extended sources, and the mixed ones of the above two, without the elaborate construction of the sparse basis. The proposed method constructs a block sparse equivalent source model and promotes a block sparse solution by imposing a structured prior on the equivalent source model and estimating the posterior of the model by using the SBL, which can achieve the accurate reconstruction of the radiated sound fields of different types of sources simply by adjusting the block size. Numerical simulation and experimental results demonstrate the validity and superiority of the proposed method, and the effects of two key parameters, the block size, and sparsity pruning threshold value are investigated through simulations.