Oxygen reduction reaction coupled electro-oxidation for highly-efficient and sustainable water treatment.

Electro-oxidation (EO) technology demonstrates significant potential in wastewater treatment. However, the high energy consumption has become a pivotal constraint hindering its large-scale implementation. Herein, we design an EO and 4-electron oxygen reduction reaction coupled system (EO-4eORR) to replace the traditional EO and hydrogen evolution reaction (HER) coupled system (EO-HER). The theoretical cathodic potential of the electrolytic reactor is tuned from 0 V (vs. RHE) in HER to 1.23 V (vs. RHE) in 4eORR, which greatly decreases the required operation voltage of the reactor. Moreover, we demonstrate that convection can improve the mass transfer of oxygen and organic pollutants in the reaction system, leading to low cathodic polarization and high pollutant removal rate. Compared with traditional EO-HER system, the energy consumption of the EO-4eORR system under air aeration for 95% total organic carbon (TOC) removal is greatly decreased to 2.61 kWh/kgTOC (only consider the electrolyzer energy consumption), which is superior to previously reported EO-based water treatment systems. The reported results in this study offer a new technical mode for development of highly efficient and sustainable EO-based treatment systems to remove organic pollutants in waste water.

Identification of common textile microplastics via autofluorescence spectroscopy coupled with k-means cluster analysis.

Microplastics are an emerging anthropogenic pollutant risk with a significant body of research dedicated to understanding the implications further. To generate the databases required to characterize the impact of microplastics on our environment, and improve recovery and recycling of current plastic materials, we need rapid, in-line characterization that can distinguish individual polymer types. Here, autofluorescence spectroscopy was investigated as an alternative characterization method to the current leading techniques based on vibrational spectroscopy. It was confirmed that the autofluorescence of seven common textile polymers (acrylic, polyester, nylon, polyethylene, polypropylene, cellulose/cotton, wool) arose due to the cluster-triggered emission phenomenon. Both simulated polymer aging via photooxidation and dyeing of the polymers were found to affect the resultant autofluorescence spectra. A total of 1485 spectra from 39 unique sample groups (polymer type, colour, and degree of photooxidation) were analysed via machine learning (k-means cluster analysis). Correct identification of the polymer type was achieved in 71% of the cases from only eight input values (normalized intensity values at three autofluorescence emission wavelengths, the total autofluorescence emission intensity, the sample RGB colour values, and the sample shape). This represents a significant step towards automated polymer identification at the sub-second time scales required for the in-line characterization of microplastics.

In Situ Production of Hydroxyl Radicals via Three-Electron Oxygen Reduction: Opportunities for Water Treatment.

The electro-Fenton (EF) process is an advanced oxidation technology with significant potential; however, it is limited by two steps: generation and activation of H2O2. In contrast to the production of H2O2 via the electrochemical two-electron oxygen reduction reaction (ORR), the electrochemical three-electron (3e-) ORR can directly activate molecular oxygen to yield the hydroxyl radical (⋅OH), thus breaking through the conceptual and operational limitations of the traditional EF reaction. Therefore, the 3e- ORR is a vital process for efficiently producing ⋅OH in situ, thus charting a new path toward the development of green water-treatment technologies. This review summarizes the characteristics and mechanisms of the 3e- ORR, focusing on the basic principles and latest progress in the in situ generation and efficient utilization of ⋅OH through the modulation of the reaction pathway, shedding light on the rational design of 3e- ORR catalysts, mechanistic exploration, and practical applications for water treatment. Finally, the future developments and challenges of efficient, stable, and large-scale utilization of ⋅OH are discussed based on achieving optimal 3e- ORR regulation and the potential to combine it with other technologies.

Bone marrow fibrosis in newly diagnosed multiple myeloma and its correlation with clinicopathological factors.

BACKGROUND: Bone marrow fibrosis (BMF) severely impacts both the quality of life and the efficacy of diagnostic procedures. However, the correlation between BMF and clinicopathological features, cytogenetic changes, and prognosis of newly diagnosed multiple myeloma (NDMM) remains unclear. This study determined the incidence, patient characteristics, and clinical outcomes of patients with NDMM with BMF. METHODS: The clinical data, histological features, and clinical outcomes of patients with NDMM were collected. Reticular fiber staining was performed on the enrolled cases, and the degree of reticular fiber overgrowth was graded. Patients with MF-2 and MF-3 were classified as the BMF+ group, and those with MF-0 and MF-1 were classified as the BMF- group, and BMF incidence was calculated. The differences in clinical data, histological features, and clinical outcomes between the BMF+ group and the BMF- group were compared. RESULTS: A consecutive series of 146 patients with NDMM were included. The incidence of MF-0, MF-1, MF-2, and MF-3 was 7.53% (11/146), 34.93% (51/146), 51.37% (75/146), and 6.16% (9/146), respectively. The incidence of BMF-MF-2 and MF-3-was 57.53% (84/146). A significant correlation was identified between the pattern of infiltration and BMF (P < 0.001). In the BMF- group, the distribution of cases with interstitial, nodular, and diffuse infiltration of plasma cells was 16 (25.8%), 21 (33.9%), and 25 (40.3%), respectively. Conversely, in the BMF+ group, these values for interstitial, nodular, and diffuse tumor cells were 9 (10.7%), 15 (17.9%), and 60 (71.4%). Furthermore, BMF was associated with a diffuse infiltration pattern. The overall survival (OS) of the BMF+ group (39.1 months; 95% confidence interval [CI]: 34.0-44.3) was lower than that of the BMF- group (45.4 months; 95% CI: 39.5-51.3), but there was no significant difference between the two groups (P = 0.221). Univariate and multivariate analyses showed that the BMF+ status was not associated with OS in patients with NDMM (P = 0.381 and P = 0.748, respectively). CONCLUSIONS: Our findings suggest that BMF is linked to a diffuse infiltration pattern, and its occurrence is not related to the prognosis of patients with NDMM, providing a basis for further exploring the BMF value in NDMM diagnosis and treatment.

Correlation of PD-L1 expression with CD8+ T cells and oxidative stress-related molecules NRF2 and NQO1 in esophageal squamous cell carcinoma.

Oxidative stress and the immune microenvironment both contribute to the pathogenesis of esophageal squamous cell carcinoma (ESCC). However, their interrelationships remain poorly understood. We aimed to examine the status of key molecules involved in oxidative stress and the immune microenvironment, as well as their relationships with each other and with clinicopathological features and prognosis in ESCC. The expression of programmed death-ligand 1 (PD-L1), CD8, nuclear factor erythroid-2 related factor-2 (NRF2), and NAD(P)H quinone oxidoreductase 1 (NQO1) was detected using immunohistochemistry in tissue samples from 176 patients with ESCC. We employed both combined positive score (CPS) and tumor proportion score (TPS) to evaluate PD-L1 expression and found a positive correlation between CPS and TPS. Notably, PD-L1 expression, as assessed by either CPS or TPS, was positively correlated with both NRF2 nuclear score and NQO1 score in stage II-IV ESCC. We also observed a positive correlation between the density of CD8+ T cells and PD-L1 expression. Furthermore, high levels of PD-L1 CPS, but not TPS, were associated with advanced TNM stage and lymph node metastases. Moreover, both PD-L1 CPS and the nuclear expression of NRF2 were found to be predictive of shorter overall survival in stage II-IV ESCC. By using the Mandard-tumor regression grading (TRG) system to evaluate the pathological response of tumors to neoadjuvant chemotherapy (NACT), we found that the TRG-5 group had higher NRF2 nuclear score, PD-L1 CPS, and TPS in pre-NACT biopsy samples compared with the TRG-3 + 4 group. The NQO1 scores of post-NACT surgical specimens were significantly higher in the TRG-5 group than in the TRG 3 + 4 group. In conclusion, the expression of PD-L1 is associated with aberrant NRF2 signaling pathway, advanced TNM stage, lymph node metastases, and unfavorable prognosis. The dysregulation of PD-L1 and aberrant activation of the NRF2 signaling pathway are implicated in resistance to NACT. Our findings shed light on the complex interrelationships between oxidative stress and the immune microenvironment in ESCC, which may have implications for personalized therapies and improved patient outcomes.

Selenium nanoparticles decorated with polysaccharides from Sargassum fusiforme protects against 6-OHDA-induced neurotoxicity in PC12 cells and rat model of Parkinson's disease.

Parkinson's disease (PD) is a neurodegenerative disorder and identifying disease-causing pathways and drugs that target them has remained challenging. Herein, selenium nanoparticles decorated with polysaccharides from Sargassum fusiforme (SFPS-SeNPs) were investigated on 6-OHDA-induced neurotoxicity in PC12 cells and rats. 6-OHDA can significantly increase neurotoxicity, oxidative stress and decrease the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) both in vitro and vivo. In vitro, treatment with SFPS-SeNPs can significantly decrease 6-OHDA cytotoxicity, reactive oxygen species (ROS) production or malondialdehyde (MDA) levels, and cell apoptosis, significantly increased the activity of SOD and GPx. In vivo, 6-OHDA exposure could also decrease the expression of Nrf2 and OH-1, while treatment with SFPS-SeNPs (1 mg Se/kg) increased. SFPS-SeNPs can protect neurons from 6-OHDA-induced neurotoxicity by regulating apoptosis and Nrf2/ARE pathway. The present study demonstrated that SFPS-SeNPs is a good candidate for developing a new drug against neurodegenerative diseases such as PD.

Host miR-146a-3p Facilitates Replication of Infectious Hematopoietic Necrosis Virus by Targeting WNT3a and CCND1.

Infectious hematopoietic necrosis virus (IHNV) is a serious pathogen that causes great economic loss to the salmon and trout industry. Previous studies showed that IHNV alters the expression patterns of splenic microRNAs (miRNAs) in rainbow trout. Among the differentially expressed miRNAs, miRNA146a-3p was upregulated by IHNV. However, it is unclear how IHNV utilizes miRNA146a-3p to escape the immune response or promote viral replication. The present study suggested that one multiplicity of infection (MOI) of IHNV induced the most significant miR-146a-3p expression at 1 day post infection (dpi). The upregulation of miR-146a-3p by IHNV was due to viral N, P, M, and G proteins and relied on the interferon (IFN) signaling pathway. Further investigation revealed that Wingless-type MMTV integration site family 3a (WNT3a) and G1/S-specific cyclin-D1-like (CCND1) are the target genes of miRNA-146a-3p. The regulation of IHNV infection by miRNA-146a-3p is dependent on WNT3a and CCND1. MiRNA-146a-3p was required for the downregulation of WNT3a and CCND1 by IHNV. Moreover, we also found that WNT3a and CCND1 are novel proteins that induce the type-I IFN response in RTG-2 cells, and both of them could inhibit the replication of IHNV. Therefore, IHNV-induced upregulation of miRNA-146a-3p promotes early viral replication by suppressing the type-I IFN response by targeting WNT3a and CCND1. This work not only reveals the molecular mechanism of miRNA-146a-3p during IHNV infection but also provides new antiviral targets for IHNV.

A Deep Insight into Perfluorooctanoic Acid Photodegradation Using Metal Ion-Exchanged Zeolites.

Treating perfluorooctanoic acid (PFOA) in an aqueous environment is problematic due to its low concentration and its high resistance to biological and chemical degradation. To tackle this challenge, combinations of pre-enrichment and photodegradation processes are promising solutions. In this work, we investigated metal ion-exchanged zeolites as adsorbents and photocatalysts for PFOA treatment. Among various transition metal ion-exchanged BEA zeolites, Fe-exchanged BEA (Fe-BEA) zeolites showed significant activity for the photodegradation of PFOA. The isolated iron species in Fe-BEA zeolite are responsible for PFOA photodegradation, whereas other iron species present from excess iron loading in the zeolite will lower its photocatalytic activity. Furthermore, it was proved via size exclusion tests using branched PFOA isomers that the photodegradation of PFOA took place on the internal surface rather than the external surface of Fe-BEA zeolite. Photodegradation of PFOA was also tested to be effective with Fe-exchanged BEA-type zeolites having various SiO2/Al2O3 ratios, but ineffective with FAU-type zeolites. The optimal Fe-BEA zeolite showed a sorption coefficient Kd of 6.0 × 105 L kg-1 at an aqueous phase PFOA concentration of 0.7 µg L-1 and a PFOA half-life of 1.8 h under UV-A irradiation. The presented study offers a deeper understanding of the use of metal ion-exchanged zeolites for photodegradation of PFOA.

Predictive value of multiple imaging predictive models for spread through air spaces of lung adenocarcinoma: A systematic review and network meta­analysis.

Spread Through Air Spaces (STAS) is involved in lung adenocarcinoma (LUAD) recurrence, where cancer cells spread into adjacent lung tissue, impacting surgical planning and prognosis assessment. Radiomics-based models show promise in predicting STAS preoperatively, enhancing surgical precision and prognostic evaluations. The present study performed network meta-analysis to assess the predictive efficacy of imaging models for STAS in LUAD. Data were systematically sourced from PubMed, Embase, Scopus, Wiley and Web of Science, according to the Cochrane Handbook for Systematic Reviews of Interventions) and A Measurement Tool to Assess systematic Reviews 2. Using Stata software v17.0 for meta-analysis, surface under the cumulative ranking area (SUCRA) was applied to identify the most effective diagnostic method. Quality assessments were performed using Cochrane Collaboration's risk-of-bias tool and publication bias was assessed using Deeks' funnel plot. The analysis encompassed 14 articles, involving 3,734 patients, and assessed 17 predictive models for STAS in LUAD. According to comprehensive analysis of SUCRA, the machine learning (ML)_Peri_tumour model had the highest accuracy (56.5), the Features_computed tomography (CT) model had the highest sensitivity (51.9) and the positron emission tomography (pet)_CT model had the highest specificity (53.9). ML_Peri_tumour model had the highest predictive performance. The accuracy was as follows: ML_Peri_tumour vs. Features_CT [relative risk (RR)=1.14; 95% confidence interval (CI), 0.99-1.32]; ML_Peri_tumour vs. ML_Tumour (RR=1.04; 95% CI, 0.83-1.30) and ML_Peri_tumour vs. pet_CT (RR=1.04; 95% CI, 0.84-1.29). Comparative analyses revealed heightened predictive accuracy of the ML_Peri_tumour compared with other models. Nonetheless, the field of radiological feature analysis for STAS prediction remains nascent, necessitating improvements in technical reproducibility and comprehensive model evaluation.

Identification of somatic mutation-driven enhancers and their clinical utility in breast cancer.

Somatic mutations contribute to cancer development by altering the activity of enhancers. In the study, a total of 135 mutation-driven enhancers, which displayed significant chromatin accessibility changes, were identified as candidate risk factors for breast cancer (BRCA). Furthermore, we identified four mutation-driven enhancers as independent prognostic factors for BRCA subtypes. In Her2 subtype, enhancer G > C mutation was associated with poorer prognosis through influencing its potential target genes FBXW9, TRIR, and WDR83. We identified aminoglutethimide and quinpirole as candidate drugs targeting the mutated enhancer. In normal subtype, enhancer G > A mutation was associated with poorer prognosis through influencing its target genes ALOX15B, LINC00324, and MPDU1. We identified eight candidate drugs such as erastin, colforsin, and STOCK1N-35874 targeting the mutated enhancer. Our findings suggest that somatic mutations contribute to breast cancer subtype progression by altering enhancer activity, which could be potential candidates for cancer therapy.

The correlation between tumor radiological features and spread through air spaces in peripheral stage IA lung adenocarcinoma: a propensity score-matched analysis.

BACKGROUND: The consolidation tumor ratio (CTR) is a predictor of invasiveness in peripheral T1N0M0 lung adenocarcinoma. However, its association with spread through air spaces (STAS) remains largely unexplored. We aimed to explore the correlation between the CTR of primary tumors and STAS in peripheral T1N0M0 lung adenocarcinoma. METHODS: We collected data from patients who underwent surgery for malignant lung neoplasms between January and November 2022. Univariate and multivariate analyses following propensity-score matching with sex, age, BMI, were performed to identify the independent risk factors for STAS. The incidence of STAS was compared based on pulmonary nodule type. A smooth fitting curve between CTR and STAS was produced by the generalized additive model (GAM) and a multiple regression model was established using CTR and STAS to determine the dose-response relationship and calculate the odds ratio (OR) and 95% confidence interval (CI). RESULTS: 17 (14.5%) were diagnosed with STAS. The univariate analysis demonstrated that the history of the diabetes, size of solid components, spiculation, pleural indentation, pulmonary nodule type, consolidation/tumor ratio of the primary tumor were statistically significant between the STAS-positive and STAS-negative groups following propensity-score matching(p = 0.047, 0.049, 0.030, 0.006, 0.026, and < 0.001, respectively), and multivariate analysis showed that the pleural indentation was independent risk factors for STAS (with p-value and 95% CI of 0.043, (8.543-68.222)). Moreover, the incidence of STAS in the partially solid nodule was significantly different from that in the solid nodule and ground-glass nodule (Pearson Chi-Square = 7.49, p = 0.024). Finally, the smooth fitting curve showed that CTR tended to be linearly associated with STAS by GAM, and the multivariate regression model based on CTR showed an OR value of 1.24 and a p-value of 0.015. CONCLUSIONS: In peripheral stage IA lung adenocarcinoma, the risk of STAS was increased with the solid component of the primary tumor. The pleural indentation of the primary tumor could be used as a predictor in evaluating the risk of the STAS.

LOXL4 Shuttled by Tumor Cells-derived Extracellular Vesicles Promotes Immune Escape in Hepatocellular Carcinoma by Activating the STAT1/PD-L1 Axis.

Emerging evidence has validated that extracellular vesicles (EVs) regulate hepatocellular carcinoma (HCC) progression, while its role in HCC immune escape remains to be elucidated. This study investigates the role of EVs-encapsulated lysyl oxidase like-4 (LOXL4) derived from tumor cells in HCC immune escape. HCC-related microarray data sets GSE36376 and GSE87630 were obtained for differential analysis, followed by identifying the essential genes related to the prognosis of HCC patients. Bone marrow-derived macrophages were treated with EVs derived from mouse Hepa 1-6 cells and cocultured with CD8 + T cells to observe the CD8 + T-cell activity. At last, a mouse HCC orthotopic xenograft model was constructed to verify the effects of HCC cell-derived EVs on the immune escape of HCC cells and tumorigenicity in vivo by delivering LOXL4. It was found that ACAT1, C4BPA, EHHADH, and LOXL4 may be the essential genes related to the prognosis of HCC patients. On the basis of the TIMER database, there was a close correlation between LOXL4 and macrophage infiltration in HCC. Besides, STAT1 was closely related to LOXL4. In vitro experiments demonstrated that LOXL4 could induce programmed death-ligand 1 expression in macrophages and immunosuppression by activating STAT1. In vivo experiments also verified that HCC cell-derived EVs promoted the immune escape of HCC cells and tumorigenicity by delivering LOXL4. LOXL4 was delivered into macrophages via EVs to induce programmed death-ligand 1 by activating STAT1 and inhibiting the killing ability of CD8 + T cells to HCC cells, thus promoting immune escape in HCC.

Expression and correlation of PD-L1 and HER2 in oesophageal squamous cell carcinoma.

AIMS: In recent years, patients with programmed cell death-Ligand 1 (PD-L1)-positive oesophageal squamous cell carcinoma (OSCC) have been able to benefit from immunotherapy. However, method for improving the treatment efficacy of PD-L1-positive patients is a problem that needs further consideration. Studies on the relationship between human epidermal growth factor receptor 2 (HER2) and PD-L1 expression have recently been reported in certain cancers, but the relationship between PD-L1 and HER2 expression in OSCC is still unclear. METHODS: A total of 263 patients with OSCC were included in the study. PD-L1 protein expression and HER2 protein expression were analysed by immunohistochemistry (IHC), and fluorescence in situ hybridisation (FISH) was performed to assess HER2 gene amplification. The significance of differences between HER2 status, PD-L1 status and clinicopathological parameters was assessed. The relationship between PD-L1 status and HER2 status was examined. RESULTS: Of the 263 OSCC cases, the PD-L1-positive expression rates were 39.2% and 77.2% in OSCC for Tumour Proportion Score (TPS) and Combined Positive Score (CPS), respectively, and PD-L1 expression was associated with the degree of tumour differentiation. The HER2 expression was positive in 24% (63/263) of cases based on IHC and FISH. HER2 expression was not significantly associated with clinicopathological characteristics. PD-L1 TPS expression and CPS expression were significantly positively correlated with HER2 expression in OSCC. CONCLUSIONS: PD-L1 expression was significantly positively correlated with HER2 expression in OSCC. The results provide valuable insight for the future application of HER2-targeted therapy combined with immunotherapy in OSCC.

Transcription factor LHX9 (LIM Homeobox 9) enhances pyruvate kinase PKM2 activity to induce glycolytic metabolic reprogramming in cancer stem cells, promoting gastric cancer progression.

BACKGROUND: Glycolytic metabolic reprogramming is a phenomenon in which cells undergo altered metabolic patterns during malignant transformation, mainly involving various aspects of glycolysis, electron transport chain, oxidative phosphorylation, and pentose phosphate pathway. This reprogramming phenomenon can be used as one of the markers of tumorigenesis and development. Pyruvate kinase is the third rate-limiting enzyme in the sugar metabolism process by specifically catalyzing the irreversible conversion of PEP to pyruvate. PURPOSE: This study aimed to reveal the critical mediator(s) that regulate glycolytic metabolism reprogramming in gastric cancer and their underlying molecular mechanism and then explore the molecular mechanisms by which LHX9 may be involved in regulating gastric cancer (GC) progression. METHODS: Firstly, we downloaded the GC and glycolysis-related microarray datasets from TCGA and MSigDB databases and took the intersection to screen out the transcription factor LHX9 that regulates GC glycolytic metabolic reprogramming. Software packages were used for differential analysis, single gene predictive analysis, and Venn diagram. In addition, an enrichment analysis of the glycolytic pathway was performed. Immunohistochemical staining was performed for LHX9 and PKM2 protein expression in 90 GC patients, and the association between their expressions was evaluated by Spearman's correlation coefficient method. Three human GC cell lines (AGS, NCI-N87, HGC-27) were selected for in vitro experimental validation. Flow cytometry was utilized to determine the stem cell marker CD44 expression status in GCSCs. A sphere formation assay was performed to evaluate the sphere-forming capabilities of GCSCs. In addition, RT-qPCR and Western blot experiments were employed to investigate the tumor stem cell markers OCT4 and SOX2 expression levels in GCSCs. Furthermore, a lentiviral expression vector was constructed to assess the impact of downregulating LHX9 or PKM2 on the glycolytic metabolic reprogramming of GCSCs. The proliferation, migration, and invasion of GCSCs were then detected by CCK-8, EdU, and Transwell assays. Subsequently, the mutual binding of LHX9 and PKM2 was verified using chromatin immunoprecipitation and dual luciferase reporter genes. In vivo experiments were verified by establishing a subcutaneous transplantation tumor model in nude mice, observing the size and volume of tumors in vivo in nude mice, and obtaining fresh tissues for subsequent experiments. RESULTS: Bioinformatics analysis revealed that LHX9 might be involved in the occurrence and development of GC through regulating glycolytic metabolism. High LHX9 expression could be used as a reference marker for prognosis prediction of GC patients. Clinical tissue assays revealed that LHX9 and PKM2 were highly expressed in GC tissues. Meanwhile, GC tissues also highly expressed glycolysis-associated protein GLUT1 and tumor cell stemness marker CD44. In vitro cellular assays showed that LHX9 could enhance its activity and induce glycolytic metabolic reprogramming in GCSCs through direct binding to PKM2. In addition, the knockdown of LHX9 inhibited PKM2 activity and glycolytic metabolic reprogramming and suppressed the proliferation, migration, and invasive ability of GCSCs. In vivo animal experiments further confirmed that the knockdown of LHX9 could reduce the tumorigenic ability of GCSCs in nude mice by inhibiting PKM2 activity and glycolytic metabolic reprogramming. CONCLUSION: The findings suggest that both LHX9 and PKM2 are highly expressed in GCs, and LHX9 may induce the reprogramming of glycolytic metabolism through transcriptional activation of PKM2, enhancing the malignant biological properties of GCSCs and ultimately promoting GC progression.

Evolution of Morphology and Distribution of Salt Crystals on a Photothermal Layer during Solar Interfacial Evaporation.

Solar interfacial evaporation (SIE) by leveraging photothermal conversion could be a clean and sustainable solution to the scarcity of fresh water, decontamination of wastewater, and steam sterilization. However, the process of salt crystallization on photothermal materials used in SIE, especially from saltwater evaporation, has not been completely understood. We report the temporal and spatial evolution of salt crystals on the photothermal layer during SIE. By using a typical oil lamp evaporator, we found that salt crystallization always initiates from the edge of the evaporation surface of the photothermal layer due to the local fast flux of the vapor to the surroundings. Interestingly, the salt crystals exhibit either compact or loose morphology, depending on the location and evaporation duration. By employing a suite of complementary analytical techniques of Raman and infrared spectroscopy and temperature mapping, we followed the evolution and spatial distribution of salt crystals, interfacial water, and surface temperature during evaporation. Our results suggested that the compact crystal structure may emerge from the recrystallization of salt in an initially porous structure, driven by continuous water evaporation from the porous and loose crystals. The holistic view provided in this study may lay the foundation for effective strategies for mitigation of the negative impact of salt crystallization in solar evaporation.