A synergistic approach combining computational fluid dynamics simulation with hydrolysis-acidification for dye wastewater treatment.

Wastewater treatment is effectively conducted using anaerobic biological methods. Nevertheless, the efficiency of these methods can be hindered by challenges like short-circuits and dead zones, particularly in treating persistent contaminants. This work utilized computational fluid dynamics (CFD) simulations to enhance water distribution, ensuring uniform interactions between solid and liquid phases, and thus mitigating issues related to short-circuits and dead zones. Such enhancements notably amplified the anaerobic biological process's efficiency. Furthermore, dye biodegradability was improved through the application of the hydrolysis acidification technique. Optimal hydraulic retention time for the hydrolysis-acidification reactor, established at 9 h, was determined via sludge cultivation and domestication for stable operation. During stable operation, an elevation in effluent volatile fatty acids was observed, alongside a COD removal rate fluctuating between 15% and 29%. Approximately 50% was noted as the rate of color removal. Simultaneously, a noticeable decrease in effluent pH occurred, with total nitrogen removal approximating 8%. An estimated BOD5/COD ratio of 0.32 was recorded. The incorporation of microbial agents led to an enhanced COD removal, ranging from 28% to 33%, thereby stabilizing the effluent BOD5/COD ratio at around 0.35. This research highlights the advantages of optimizing water distribution in anaerobic reactors, particularly when combined with hydrolysis-acidification techniques, effectively addressing issues of short-circuits and dead zones.

Contribution of immune cells to cancer-related neuropathic pain: An updated review.

Given that the incidence of cancer is dramatically increasing nowadays, cancer-related neuropathic pain including tumor-related and therapy-related pain gradually attracts more attention from researchers, which basically behaves as a metabolic-neuro-immune disorder with worse clinical outcomes and prognosis. Among various mechanisms of neuropathic pain, the common underlying one is the activation of inflammatory responses around the injured or affected nerve(s). Innate and adaptive immune reactions following nerve injury together contribute to the regulation of pain. On the other hand, the tumor immune microenvironment involving immune cells, as exemplified by lymphocytes, macrophages, neutrophils and dendritic cells, inflammatory mediators as well as tumor metastasis have added additional characteristics for studying the initiation and maintenance of cancer-related neuropathic pain. Of interest, these immune cells in tumor microenvironment exert potent functions in promoting neuropathic pain through different signaling pathways. To this end, this review mainly focuses on the contribution of different types of immune cells to cancer-related neuropathic pain, aims to provide a comprehensive summary of how these immune cells derived from the certain tumor microenvironment participate in the pathogenesis of neuropathic pain. Furthermore, the clarification of roles of various immune cells in different tumor immune microenvironments associated with certain cancers under neuropathic pain states constitutes innovative biology that takes the pain field in a different direction, and thereby provides more opportunities for novel approaches for the prevention and treatment of cancer-related neuropathic pain.

Novel thermodynamic mechanisms of co-conditioning with polymeric aluminum chloride and polyacrylamide for improved sludge dewatering: A paradigm shift in the field.

This study investigated the combined effects of polymeric aluminum chloride (PAC) and polyacrylamide (PAM) on sludge dewatering, aiming to unveil underlying mechanisms. Co-conditioning with 15 mg g-1 PAC and 1 mg g-1 PAM achieved optimal dewatering, reducing specific filtration resistance (SFR) of co-conditioned sludge to 4.38 × 1012 m-1kg-1, a mere 48.1% of raw sludge's SFR. Compared with the CST of raw sludge (36.45 s), sludge sample can be significantly reduced to 17.7 s. Characterization tests showed enhanced neutralization and agglomeration in co-conditioned sludge. Theoretical calculations revealed elimination of interaction energy barriers between sludge particles post co-conditioning, converting sludge surface from hydrophilic (3.03 mJ m-2) to hydrophobic (-46.20 mJ m-2), facilitating spontaneous agglomeration. Findings explain improved dewatering performance. Based on Flory-Huggins lattice theory, connection between polymer structure and SFR was established. Raw sludge formation triggered significant change in chemical potential, increasing bound water retention capacity and SFR. In contrast, co-conditioned sludge exhibited thinnest gel layer, reducing SFR and significantly improving dewatering. These findings represent a paradigm shift, shedding new light on fundamental thermodynamic mechanisms of sludge dewatering with different chemical conditioning.

Efficacy of erector spinae plane block for postoperative analgesia lumbar surgery: a systematic review and meta-analysis.

OBJECTIVES: The erector spinae plane (ESP) block is a newly defined regional anesthesia technique first described in 2016. The aim of this meta-analysis is to assess the efficacy of ESP block in improving analgesia following lumbar surgery. METHODS: PubMed, EMBASE, Cochrane Library, and Web of Science were searched for randomized controlled trials (RCTs) that compared the analgesic efficacy of the ESP block with non-block care for lumbar surgery from inception 3 August 2021. The primary outcomes were postoperative opioid consumption and pain scores during the first 24 h. Postoperative pain was measured as pain at rest and on movement at postoperative 0, 4, 8, 12, and 24 h expressed on a visual analog scale (VAS), where 0 = no pain and 10 = the most severe pain. RESULTS: 11 studies involving 775 patients were included in our analysis. The use of ESP block significantly decreased 24-h opioid consumption (WMD, -8.70; 95% CI, -10.48 to -6.93; I2 = 97.5%; P < 0.001) compared with the non-block. Moreover, ESP block reduced pain scores at postoperative time-points up to 24 h. ESP block also prolonged the time to first analgesic request (WMD = 6.93; 95% CI: 3.44 to 10.43, I2 = 99.8%; P < 0.001). There was less PONV with ESP block versus non-block group (RR, 0.354; 95% CI, 0.23 to 0.56; I2 = 25.2%; P < 0.001), but no difference in pruritus. CONCLUSIONS: ESP block provides less opioid consumption and PONV, lower pain scores, and longer time to first analgesic request in patients undergoing lumbar surgery compared to general anesthesia alone.

A low-cost and sustainable solution for nitrate removal from secondary effluent: Macroporous ion exchange resin treatment.

Macroporous ion exchange resin has excellent selectivity to nitrogen (N), phosphorus (P) and partially soluble refractory organic compounds contained in the secondary effluent of wastewater treatment plants (WWTP). In this study, macroporous ion exchange resins were chosen as an alternative to single biochemical nitrogen removal processes. Various conditions were examined to optimize adsorption performance, and the adsorption mechanism was explored through isotherm fitting, thermodynamic parameter calculation, and kinetic analysis. The experiment demonstrated that the resin exhibited strong selectivity for nitrate (NO3-) and achieved an equilibrium adsorption amount of 9.8924 mg/g and an equilibrium adsorption time of 60 min at 25 °C. The resin denitrification pilot plant demonstrated stable operation for two months and achieved COD<20 mg/L, TN < 1.5 mg/L, and NH4+-N<0.5 mg/L. The removal rates of COD, TP, NH4+-N, NO3--N, and TN were 41.65%, 42.96%, 55.37%, 91.8%, and 90.81%, respectively. After the resin was regenerated, the removal rates of NO3--N, TN and the regeneration recovery rate were above 90%. Through cost analysis, the treatment cost of the pilot plant is only 0.104 $/m3. This study presents a practical, low-cost, and efficient treatment method for the deep treatment of secondary effluent from WWTP in practical engineering, providing new ideas and theoretical guidance.

Enhanced denitrification performance of granular sludge for the treatment of waste brine from ion exchange resin process.

Ion exchange resin process is a widely used process in wastewater treatment plants, but its waste brine is characterized by high salinity and nitrate concentration, leading to costly treatment. This study innovatively explored the use of an up-flow anaerobic sludge bed (USB) for the treatment of waste brine from ion exchange resin process, following a pilot-scale ion exchange resin process. Specifically, the D890 ion exchange resin was employed for nitrate removal from secondary effluent, with resin regeneration using 4% NaCl solution. The USB was inoculated with anaerobic granular sludge and acclimated under various single-factor conditions, which revealed the optimal pH range of 6.5-9, salt concentration of 2%, hydraulic retention time of 12 h, C/N ratio of 3.3, and up-flow velocity of 1.5 m/h for reactor operation. This study provides a novel approach for the cost-effective treatment of waste brine from ion exchange resin process. The study found that the denitrification efficiency was highest when the NO3--N concentration was around 200 mg/L, with NO3--N and TN removal rates exceeding 95% and 90%, respectively, under optimal operating conditions. Characterization of the granular sludge during different phases of the operation revealed a significant increase in proteobacteria and gradually became the dominant species over time. This study presents a novel, cost-effective approach to treat waste brine from ion exchange resin process, and the long-term stable operation of the reactor offers a reliable option for resin regeneration wastewater treatment.

Bronchial blocker versus double-lumen endobronchial tube in minimally invasive cardiac surgery.

BACKGROUND: To compare the therapeutic value of a bronchial blocker (BB) with a double-lumen tube (DLT) in minimally invasive cardiac surgery (MICS). METHODS: Sixty patients who underwent MICS were randomized to use either a DLT (Group D, n = 30) or a BB (Group B, n = 29; one failed was omitted). The following data were collected: time of intubation and tube localization; incidence of tube displacement; postoperative sore throat and hoarseness; time of cardiopulmonary bypass; maintenance time for SpO2 < 90% (PaCO2 < 60 mmHg); mean arterial pressure and heart rate; SpO2, PaO2, PaCO2, EtCO2, mean airway pressure, and airway peak pressure; surgeons' satisfaction with anesthesia; and short-term complications. RESULTS: The times of intubation and tube localization were significantly longer in Group B than in Group D (P < 0.05). Patients in Group B exhibited significantly lower incidence of tube displacement, postoperative sore throat, and hoarseness when compared with patients in Group D (P < 0.05). Mean arterial pressure and heart rate were significantly lower in Group B than in Group D after tracheal intubation (P < 0.05). The mean airway pressure and airway peak pressure were significantly lower in Group B than in Group D after one-lung ventilation (P < 0.05). SpO2 and PaO2 in Group B were significantly higher than in group D after cardiopulmonary bypass (P < 0.05). No short-term postoperative complications were observed in patients of Groups B and D during 3 month follow-up. CONCLUSION: BB can be a potential alternative to the conventional DLT for lung isolation in MICS. TRIAL REGISTRATION: ChiCTR1900024250, July 2, 2019.

Randomized controlled trial of moderate hypothermia versus deep hypothermia anesthesia on brain injury during Stanford A aortic dissection surgery.

This study aimed to compare the effects of moderate versus deep hypothermia anesthesia for Stanford A aortic dissection surgery on brain injury. A total of 82 patients who would undergo Stanford A aortic dissection surgery were randomized into two groups: moderate hypothermia group (MH, n = 40, nasopharyngeal temperature 25 °C, and rectal temperature 28 °C) and deep hypothermia group (DH, n = 42, nasopharyngeal temperature 20 °C, and rectal temperature 25 °C). Different vascular replacement techniques including aortic root replacement, Bentall, and Wheat were used. The intraoperative and postoperative indicators of these patients were recorded. There were no differences in intraoperative and postoperative measures between MH and DH groups. The concentrations of neuron-specific enolase and S-100ß increased with operation time, and were significantly lower in MH group than those in the DH group (P < 0.05). The occurrence rates of complications including chenosis, postoperative agitation, and neurological complications in MH group were significantly lower than in DH group. The recovery time, postoperative tube, and ICU intubation stay were significantly shorter in MH group than those in DH group (P < 0.05). There were no significant differences revealed in hospital stay and death rate. MH exhibited better cerebral protective effects, less complications, and shorter tube time than DH in surgery for Stanford A aortic dissection.

The Role of Neural Plasticity in Depression: From Hippocampus to Prefrontal Cortex.

Neural plasticity, a fundamental mechanism of neuronal adaptation, is disrupted in depression. The changes in neural plasticity induced by stress and other negative stimuli play a significant role in the onset and development of depression. Antidepressant treatments have also been found to exert their antidepressant effects through regulatory effects on neural plasticity. However, the detailed mechanisms of neural plasticity in depression still remain unclear. Therefore, in this review, we summarize the recent literature to elaborate the possible mechanistic role of neural plasticity in depression. Taken together, these findings may pave the way for future progress in neural plasticity studies.

Alantolactone Induces Apoptosis and Cell Cycle Arrest on Lung Squamous Cancer SK-MES-1 Cells.

Alantolactone, a sesquiterpene lactone compound, has variety of pharmacological properties, including anti-inflammatory and antineoplastic effects. In our study, alantolactone inhibited cancer cell proliferation. To explore the mechanisms underlying its antitumor action, we further examined apoptotic cells and cell cycle distribution using flow cytometry analysis. Alantolactone triggered apoptosis and induced cell cycle G1/G0 phase arrest. Furthermore, the expressions of caspases-8, -9, -3, PARP, and Bax were significantly upregulated, while antiapoptotic factor Bcl-2 expression was inhibited. In addition, the expressions of cyclin-dependent kinase 4 (CDK4), CDK6, cyclin D3, and cyclin D1 were downregulated by alantolactone. Therefore, our findings indicated that alantolactone has an antiproliferative role on lung squamous cancer cells, and it may be a promising chemotherapeutic agent for squamous lung cancer SK-MES-1 cells.

Expression and localization of GEN1 in mouse mammary epithelial cells.

GEN1, a Holliday junction resolvase, is involved in homologous repair of DNA double strand break and in maintaining centrosome integrity. Although GEN1 mutants have been reported in breast cancer patients and cell lines, little is currently known about the functions of GEN1 in the development and oncogenic transformation of mammary gland. In the present study, we demonstrate that GEN1 expression is correlated with mammary epithelial cell proliferation, differentiation in various physiological stages as well as casein. By immunofluorescence analysis, the centrosomal association of GEN1 is confirmed in mammary epithelial cells. Additionally, GEN1 is likely involved in DNA damage response of breast cancer cell lines. These results suggest that GEN1 may play an important role in the development of mammary gland; its response upon DNA damage indicates that GEN1 gene alteration may contribute to breast cancer formation.

Innovative treatment of industrial effluents through combining ferric iron and attapulgite application.

The escalation of industrial activities has escalated the production of pharmaceutical and dyeing effluents, raising significant environmental issues. In this investigation, a hybrid approach of Fenton-like reactions and adsorption was used for deep treatment of these effluents, focusing on effects of variables like hydrogen peroxide concentration, catalyst type, pH, reaction duration, temperature, and adsorbent quantity on treatment effectiveness, and the efficacy of acid-modified attapulgite (AMATP) and ferric iron (Fe(III))-loaded AMATP (Fe(III)-AMATP) was examined. Optimal operational conditions were determined, and the possibility of reusing the catalysts was explored. Employing Fe3O4 as a heterogeneous catalyst and AMATP for adsorption, CODCr was reduced by 78.38-79.14%, total nitrogen by 71.53-77.43%, and phosphorus by 97.74-98.10% in pharmaceutical effluents. Similarly, for dyeing effluents, Fe(III)-AMATP achieved 79.87-80.94% CODCr, 68.59-70.93% total nitrogen, and 79.31-83.33% phosphorus reduction. Regeneration experiments revealed that Fe3O4 maintained 59.48% efficiency over three cycles, and Fe(III)-AMATP maintained 62.47% efficiency over four cycles. This work offers an economical, hybrid approach for effective pharmaceutical and dyeing effluent treatment, with broad application potential.

Recent Research Advances in Nano-Based Drug Delivery Systems for Local Anesthetics.

From a clinical perspective, local anesthetics have rather widespread application in regional blockade for surgery, postoperative analgesia, acute/chronic pain control, and even cancer treatments. However, a number of disadvantages are associated with traditional local anesthetic agents as well as routine drug delivery administration ways, such as neurotoxicity, short half-time, and non-sustained release, thereby limiting their application in clinical practice. Successful characterization of drug delivery systems (DDSs) for individual local anesthetic agents can support to achieve more efficient drug release and prolonged duration of action with reduced systemic toxicity. Different types of DDSs involving various carriers have been examined, including micromaterials, nanomaterials, and cyclodextrin. Among them, nanotechnology-based delivery approaches have significantly developed in the last decade due to the low systemic toxicity and the greater efficacy of non-conventional local anesthetics. Multiple nanosized materials, including polymeric, lipid (solid lipid nanoparticles, nanostructured lipid carriers, and nanoemulsions), metallic, inorganic non-metallic, and hybrid nanoparticles, offer a safe, localized, and long-acting solution for pain management and tumor therapy. This review provides a brief synopsis of different nano-based DDSs for local anesthetics with variable sizes and structural morphology, such as nanocapsules and nanospheres. Recent original research utilizing nanotechnology-based delivery systems is particularly discussed, and the progress and strengths of these DDSs are highlighted. A specific focus of this review is the comparison of various nano-based DDSs for local anesthetics, which can offer additional indications for their further improvement. All in all, nano-based DDSs with unique advantages provide a novel direction for the development of safer and more effective local anesthetic formulations.

Feasibility and optimization of a novel upflow denitrification reactor using denitrifying granular sludge for nitric acid pickling wastewater treatment.

Stainless steel is highly valued for its superior resistance to corrosion. However, the pickling process involved in stainless steel production generates abundant NO3--N, causing health and environmental risks. To address this issue, this study proposed a novel solution utilizing an up-flow denitrification reactor and denitrifying granular sludge for treating NO3--N pickling wastewater under high NO3--N loading. It was found that, the denitrifying granular sludge exhibited stable denitrification performance with the highest denitrification rate of 2.79 gN/(gVSS·d) and average removal rates of NO3--N and TN of 99.94% and 99.31%, respectively, under optimal operating conditions of pH 6-9, temperature 35 °C, C/N ratio 3.5, hydraulic retention time (HRT) 11.1 h and ascending flow rate 2.75 m/h. This process reduced carbon source usage by 12.5-41.7% as compared to traditional denitrification methods. These findings demonstrate the efficacy of combining granular sludge and an up-flow denitrification reactor for treating nitric acid pickling wastewater.

Cingulate cGMP-dependent protein kinase I facilitates chronic pain and pain-related anxiety and depression.

ABSTRACT: Patients with chronic pain often experience exaggerated pain response and aversive emotion, such as anxiety and depression. Central plasticity in the anterior cingulate cortex (ACC) is assumed to be a critical interface for pain perception and emotion, which has been reported to involve activation of NMDA receptors. Numerous studies have documented the key significance of cGMP-dependent protein kinase I (PKG-I) as a crucial downstream target for the NMDA receptor-NO-cGMP signaling cascade in regulating neuronal plasticity and pain hypersensitivity in specific regions of pain pathway, ie, dorsal root ganglion or spinal dorsal horn. Despite this, whether and how PKG-I in the ACC contributes to cingulate plasticity and comorbidity of chronic pain and aversive emotion has remained elusive. Here, we uncovered a crucial role of cingulate PKG-I in chronic pain and comorbid anxiety and depression. Chronic pain caused by tissue inflammation or nerve injury led to upregulation of PKG-I expression at both mRNA and protein levels in the ACC. Knockdown of ACC-PKG-I relieved pain hypersensitivity as well as pain-associated anxiety and depression. Further mechanistic analysis revealed that PKG-I might act to phosphorylate TRPC3 and TRPC6, leading to enhancement of calcium influx and neuronal hyperexcitability as well as synaptic potentiation, which results in the exaggerated pain response and comorbid anxiety and depression. We believe this study sheds new light on the functional capability of ACC-PKG-I in modulating chronic pain as well as pain-associated anxiety and depression. Hence, cingulate PKG-I may represent a new therapeutic target against chronic pain and pain-related anxiety and depression.

Fundamental thermodynamic mechanisms of membrane fouling caused by transparent exopolymer particles (TEP) in water treatment.

While transparent exopolymer particles (TEP) has high fouling potential, its underlying fouling mechanisms have not yet been well revealed. In current work, fouling characteristics of TEP under different Ca2+ concentrations (0 to 1.5 mM) were investigated. TEP quantification and filtration tests showed that TEP contents increased with Ca2+ concentration, while TEP's specific filtration resistance (SFR) under the influence of Ca2+ concentration presented a unimodal pattern. The peak of TEP's SFR reached at Ca2+ concentration of 1 mM when SA concentration was 0.3 g·L-1. A series of characterizations suggested that microstructure transformation of TEP particles was the main contributor to the resistance variations of TEP solution. The optical microscope observation showed that above and below the critical Ca2+ concentration (1 mM when SA concentration is 0.3 g·L-1 in this study), the formed TEP existed in the form of c-TEP (average particle size is 0.24 µm) and p-TEP (average particle size is 1.05 µm), respectively. Thermodynamic analysis showed that the adhesion ability of c-TEP (-249,989 and - 303,692 kT) was more than 19 times than that of p-TEP (-12,905 kT), which would accelerate foulant layer formation. In addition, below the critical value, the increased SFR with Ca2+ concentration could be explained by integrating Flory-Huggins lattice theory with the preferential intermolecular coordination. Above the critical value, the decreased SFR can be attributed to the formation of a "large-size crack structure" cake layer from the p-TEP. This study revealed fundamental mechanisms of membrane fouling caused by TEP, greatly deepening understanding of TEP fouling, and facilitating to development of effective fouling control strategies.

Molecular insights into impacts of EDTMPA on membrane fouling caused by transparent exopolymer particles (TEP).

While ethylenediamine tetramethylenephosphonic acid (EDTMPA) has been emerged as a stronger chelating agent than ethylene diamine tetraacetic acid (EDTA) for fouling mitigation, and transparent exopolymer particles (TEP) is a major foulant in membrane-based water treatment process, effects of EDTMPA on TEP fouling and the underlying mechanism have been not yet studied. In this study, Flory-Huggins lattice theory was combined with density functional theory (DFT) technology to explore this subject at molecular level. Filtration experiments showed a unimodal pattern of specific filtration resistance (SFR) of TEP sample with Ca2+ concentration in range of 0-3 mM. For the TEP sample with the peak SFR value at 1.5 mM Ca2+, continuous addition of EDTMPA (from 0 to 100 mg·L-1) resulted in a sustained decrease in SFR. Energy dispersive spectroscopy (EDS) mapping characterization showed the continuing decline of calcium content in the TEP layer with increase of EDTMPA addition, indicating that EDTMPA successfully captured Ca2+ from alginate­calcium ligation (TEP), and then disintegrated the TEP structure. DFT simulation showed that Ca2+ preferentially coordinated with the terminal carboxyl groups of alginate chains to form a coordination configuration that is conducive to stretch the three-dimensional polymer network. Such a network corresponded to an extremely high SFR according to Flory-Huggins theory. EDTMPA addition caused disintegration of the coordination configuration of Ca2+ binding to terminal carboxyl groups, which further resulted in collapse and flocculation of TEP gel network structure, thus leading to a continuous SFR decrease. This work provided deep thermodynamic insights into effects of EDTMPA on TEP-associated fouling at molecular level, facilitating to better understanding and mitigation of membrane fouling.

Mechanistic insights into Ca-alginate gel-associated membrane fouling affected by ethylene diamine tetraacetic acid (EDTA).

While transparent exopolymer particles (TEP) is a major foulant, and ethylene diamine tetraacetic acid (EDTA) is a strong chelating agent frequently used for fouling mitigation in membrane-based water treatment processes, little has been known about TEP-associated membrane fouling affected by EDTA. This work was performed to investigate roles of EDTA addition in TEP (Ca-alginate gel was used as a TEP model) associated fouling. It was interestingly found that, TEP had rather high specific filtration resistance (SFR) of 2.49 × 1015 m-1·kg-1, and SFR of TEP solution firstly decreased and then increased rapidly with EDTA concentration increase (0-1 mM). A series of characterizations suggested that EDTA took roles in SFR of TEP solution by means of changing TEP microstructure. The rather high SFR of TEP layer can be attributed to the big chemical potential gap during filtration described by the extended Flory-Huggins lattice theory. Initial EDTA addition disintegrated TEP structure by EDTA chelating calcium in TEP, inducing reduced SFR. Continuous EDTA addition decreased solution pH, resulting into no effective chelating and accumulation of EDTA on membrane surface, increasing SFR. It was suggested that factors increasing homogeneity of TEP gel will increase SFR, and vice versa. This study revealed the thermodynamic mechanism of TEP fouling behaviors affected by EDTA, and also demonstrated the importance of EDTA dosage and pH adjustment for TEP-associated fouling control.

Effects of polysaccharides' molecular structure on membrane fouling and the related mechanisms.

Fouling behaviors of polysaccharides vary with their structure, while the mechanisms underlying this phenomenon remain unexplored. This work was carried out to explore the thermodynamic fouling mechanisms of polysaccharides with different structure. Carrageenan and xanthan gum were selected as the model polysaccharides with structure of straight and branch chains, respectively. Batch filtration experiments showed that xanthan gum solution corresponded to a more rapid flux decline trend, and specific filtration resistance (SFR) of xanthan gum (2.32 × 1015 m-1 kg-1) was over 10 times than that of carrageenan (2.21 × 1014 m-1 kg-1). It was found that, xanthan gum possessed a more disordered structure and a rather higher viscosity (15.03 mPa·s V.S. 1.98 mPa·s for carrageenan). Calculation of extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory showed higher adhesion energy of xanthan gum (-42.82 my m-2 V.S. -23.26 mJ m-2 for carrageenan). Scanning electron microscopy (SEM) analyses showed that xanthan gum gel layer had a more homogenous structure and rigid polymer backbone, indicating better mixing with water to form a gel. As verified by heating experiments, such a structure tended to contain more bound water. According to this information, Flory-Huggins lattice theory was introduced to build a bridge between polymeric structure and SFR. It was revealed that branch structure corresponded to higher chemical potential change during gel layer formation, and higher ability to carry bound water, resulting in higher filtration resistance during filtration process. This work revealed the fundamental thermodynamic mechanism of membrane fouling caused by polysaccharides with different structure, deepening understanding of membrane fouling.