ObjectiveTo investigate the effects of prostaglandin E₂ （PGE₂） microinjection into the median preoptic nucleus （MnPO） on core body temperature in female mice， and to clarify its underlying mechanism. MethodsMicroinjection cannula were implanted into the MnPO of female mice using stereotaxic surgery.Subsequently， a multi-channel temperature acquisition system was used to simultaneously monitor rectal and brown adipose tissue （BAT） temperatures before and after intra-MnPO injections of different reagents.To investigate the thermoregulatory effects of the microinjection of PGE₂ into the MnPO， 12 female C57BL/6 mice were randomly divided into a saline group （n=6） and a PGE₂ group （n=6）， which were injected with 0.1 μL saline and PGE₂ （2.8 mmol/L）， respectively.To determine whether E-series prostaglandin receptor （EP）1， EP3， and EP4 receptors mediate the thermoregulatory effects of PGE₂， 15 female C57BL/6 mice were randomly divided into 3 groups （n=5 per group）.Mice in each group first received an injection of 0.1 μL PGE2 （2.8 mmol/L） into the MnPO. After their body temperature returned to baseline levels， they were subsequently injected with a mixture of either EP1， EP3 or EP4 antagonist （ant） （20 mmol/L） + PGE2 （2.8 mmol/L）. ResultsCompared with baseline level， the rectal temperature （P<0.01） and BAT temperature （P<0.001） of female mice both increased significantly after microinjection of PGE₂ into the MnPO.Compared with the saline group， the increases in rectal temperature （P<0.001） and BAT temperature （P<0.000 1） were significantly greater in the PGE₂ group of mice.Furthermore， following the injection of PGE₂ into MnPO， the increase in BAT temperature was found to be significantly greater than that in rectal temperature in mice （P<0.001）.Compared to the administration of PGE₂ alone， co-injection of an EP3 ant + PGE₂ into the MnPO of mice resulted in a significantly smaller increase in both rectal temperature （P<0.001） and BAT temperature （P<0.001）.In contrast， the increases in rectal and BAT temperatures following MnPO injection of either EP1 ant + PGE₂ or EP4 ant + PGE₂ were not statistically significant （P>0.05）. ConclusionInjection of PGE₂ into the MnPO elevates BAT and core body temperature in female mice via the EP3 receptor.

Cancer remains a leading cause of global mortality, necessitating the development of advanced therapeutic strategies with enhanced efficacy and reduced systemic toxicity. Among promising bioactive agents, lactoferrin (LF)—a multifunctional iron-binding glycoprotein abundantly found in mammalian milk and exocrine secretions—has garnered significant interest for its potent and multifaceted anti-cancer properties. This review provides a comprehensive analysis of the current understanding of LF’s role in oncology, encompassing its structural biology, diverse mechanisms of action, and groundbreaking advancements in its application through nano-engineering. LF exerts anti-tumor effects through multiple pathways, including extracellular action, intracellular action, and immune regulation. It demonstrates a remarkable affinity for cancer cell membranes, binding to overexpressed anionic components such as glycosaminoglycans and sialic acids, as well as to specific receptors including the low-density lipoprotein receptor-related protein-1 (LRP-1). This selective binding facilitates targeted uptake. Upon internalization, LF orchestrates a direct assault by inducing cell-cycle arrest in phases such as G0/G1 or S phase through the modulation of key regulators including cyclins, CDKs, and p53. Furthermore, it promotes programmed cell death via apoptotic pathways, involving caspase activation and downregulation of anti-apoptotic proteins such as survivin. A more recently elucidated mechanism is the induction of ferroptosis, an iron-dependent form of cell death characterized by overwhelming lipid peroxidation. Beyond direct cytotoxicity, LF acts as a potent immunomodulator. It enhances natural killer (NK) cell activity, modulates T-lymphocyte populations, and crucially reprograms tumor-associated macrophages (TAMs) from a pro-tumor M2 state to an anti-tumor M1 state, thereby reversing the immunosuppressive tumor microenvironment (TME). The translation of LF’s potential has been significantly accelerated by nanotechnology. The inherent biocompatibility and natural tumor-targeting capabilities of LF make it an ideal platform for sophisticated drug-delivery systems. This review details various fabrication strategies for LF-based nanoparticles (NPs), including self-assembly, sol-in-oil emulsion, and electrostatic nanocomplexes, among others. Research demonstrates that nano-formulations not only protect LF from degradation but also enhance its bioactivity and anti-cancer potency. More importantly, LF NPs serve as versatile carriers for a wide array of therapeutic agents, including conventional chemotherapeutics, natural compounds, and imaging agents. These engineered systems enable synergistic therapy and facilitate site-specific delivery. Notably, the ability of LF to bind to receptors on the blood-brain barrier (BBB) has been leveraged to develop nano-systems for glioblastoma treatment. Other innovative designs utilize LF to modulate the TME—for instance, by alleviating tumor hypoxia to sensitize cells to radiotherapy and chemotherapy. Despite compelling pre-clinical evidence, the clinical translation of LF and its nano-formulations remains nascent. While early-phase trials have established a favorable safety profile for recombinant human LF, larger Phase III studies have yielded mixed results, underscoring the complexity of its action in humans. Key challenges include enhancing drug targeting, optimizing loading efficiency, ensuring batch-to-batch reproducibility, and achieving deep tumor penetration. Future research must focus on the rational design of next-generation LF-NPs. This entails developing standardized manufacturing protocols, engineering “smart” stimuli-responsive systems for targeted drug release in the TME, and constructing multi-targeting platforms. A concerted interdisciplinary effort is paramount to bridge the gap between bench and bedside. In conclusion, LF, particularly in its nano-engineered forms, represents a highly promising and versatile agent in the oncological arsenal, holding immense potential for precise and effective cancer therapy.

Cancer remains a leading cause of global mortality, necessitating the development of advanced therapeutic strategies with enhanced efficacy and reduced systemic toxicity. Among promising bioactive agents, lactoferrin (LF)—a multifunctional iron-binding glycoprotein abundantly found in mammalian milk and exocrine secretions—has garnered significant interest for its potent and multifaceted anti-cancer properties. This review provides a comprehensive analysis of the current understanding of LF’s role in oncology, encompassing its structural biology, diverse mechanisms of action, and groundbreaking advancements in its application through nano-engineering. LF exerts anti-tumor effects through multiple pathways, including extracellular action, intracellular action, and immune regulation. It demonstrates a remarkable affinity for cancer cell membranes, binding to overexpressed anionic components such as glycosaminoglycans and sialic acids, as well as to specific receptors including the low-density lipoprotein receptor-related protein-1 (LRP-1). This selective binding facilitates targeted uptake. Upon internalization, LF orchestrates a direct assault by inducing cell-cycle arrest in phases such as G0/G1 or S phase through the modulation of key regulators including cyclins, CDKs, and p53. Furthermore, it promotes programmed cell death via apoptotic pathways, involving caspase activation and downregulation of anti-apoptotic proteins such as survivin. A more recently elucidated mechanism is the induction of ferroptosis, an iron-dependent form of cell death characterized by overwhelming lipid peroxidation. Beyond direct cytotoxicity, LF acts as a potent immunomodulator. It enhances natural killer (NK) cell activity, modulates T-lymphocyte populations, and crucially reprograms tumor-associated macrophages (TAMs) from a pro-tumor M2 state to an anti-tumor M1 state, thereby reversing the immunosuppressive tumor microenvironment (TME). The translation of LF’s potential has been significantly accelerated by nanotechnology. The inherent biocompatibility and natural tumor-targeting capabilities of LF make it an ideal platform for sophisticated drug-delivery systems. This review details various fabrication strategies for LF-based nanoparticles (NPs), including self-assembly, sol-in-oil emulsion, and electrostatic nanocomplexes, among others. Research demonstrates that nano-formulations not only protect LF from degradation but also enhance its bioactivity and anti-cancer potency. More importantly, LF NPs serve as versatile carriers for a wide array of therapeutic agents, including conventional chemotherapeutics, natural compounds, and imaging agents. These engineered systems enable synergistic therapy and facilitate site-specific delivery. Notably, the ability of LF to bind to receptors on the blood-brain barrier (BBB) has been leveraged to develop nano-systems for glioblastoma treatment. Other innovative designs utilize LF to modulate the TME—for instance, by alleviating tumor hypoxia to sensitize cells to radiotherapy and chemotherapy. Despite compelling pre-clinical evidence, the clinical translation of LF and its nano-formulations remains nascent. While early-phase trials have established a favorable safety profile for recombinant human LF, larger Phase III studies have yielded mixed results, underscoring the complexity of its action in humans. Key challenges include enhancing drug targeting, optimizing loading efficiency, ensuring batch-to-batch reproducibility, and achieving deep tumor penetration. Future research must focus on the rational design of next-generation LF-NPs. This entails developing standardized manufacturing protocols, engineering “smart” stimuli-responsive systems for targeted drug release in the TME, and constructing multi-targeting platforms. A concerted interdisciplinary effort is paramount to bridge the gap between bench and bedside. In conclusion, LF, particularly in its nano-engineered forms, represents a highly promising and versatile agent in the oncological arsenal, holding immense potential for precise and effective cancer therapy.

Malignant tumors represent a major threat to global health. Conventional anti-tumor pharmacotherapy often encounters challenges such as drug resistance, highlighting an urgent need for the development of novel therapeutic strategies. Fatty acid synthase (FASN), the key enzyme catalyzing de novo fatty acid synthesis, is subject to precise regulation at multiple levels, including transcriptional control, various post-translational modifications such as ubiquitination and phosphorylation, as well as modulation by diverse signaling pathways. Recent studies have revealed that FASN is aberrantly overexpressed in various malignant tumors and is closely associated with tumor progression and poor patient prognosis. FASN is a homodimer composed of seven functional domains that catalyzes the NADPH-dependent condensation of acetyl-CoA and malonyl-CoA to generate saturated fatty acids, primarily palmitic acid. Its stability is regulated by multiple ubiquitin ligases and deubiquitinating enzymes. Additionally, FASN is subject to upstream regulation via neural precursor cell-expressed developmentally downregulated 8 (Nedd8) modification and the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway, thereby establishing a metabolic-signaling positive feedback loop. As a core executor of metabolic reprogramming, FASN promotes tumorigenesis through dual mechanisms. First, its fatty acid synthesis product, palmitate, participates in membrane phospholipid synthesis, lipid raft formation, and protein palmitoylation, thereby activating several key oncogenic signaling pathways, including PI3K/AKT/mTOR, wingless-type MMTV integration site family member (Wnt)/β‑catenin, and signal transducer and activator of transcription 3 (STAT3)/matrix metalloproteinase (MMP), leading to tumor development and progression. Second, FASN plays a pivotal role in modulating the anti-tumor functions of immune cells and remodeling the tumor immune microenvironment. Specifically, FASN enhances immune checkpoint inhibition by inducing programmed death-ligand 1 (PD-L1) palmitoylation, suppresses the activation of cytotoxic T lymphocytes and natural killer cells, and promotes the polarization of M2-type macrophages, consequently facilitating tumor immune evasion and malignant progression. Precisely due to its significant overexpression in tumor cells, its critical functional role, and its differential expression compared to normal cells, FASN has emerged as a highly promising target for anti-tumor drug development. Highly selective small-molecule inhibitors, notably represented by TVB-2640, have advanced to clinical trial stages and demonstrated favorable anti-tumor activity. Furthermore, the combination of FASN inhibitors with other chemotherapeutic agents or targeted drugs can overcome the limitations of monotherapy through synergistic effects or by resensitizing tumor cells to conventional drugs, achieving a “1+1>2” therapeutic outcome. With the advancement of modern traditional Chinese medicine (TCM), numerous active ingredients derived from TCM have been confirmed to exert anti-tumor effects by modulating FASN-related pathways. This integrated approach leverages the precision of Western medicine while simultaneously harnessing the holistic regulatory benefits of TCM to alleviate the side effects of radiotherapy and chemotherapy. Despite the promising prospects of FASN-targeted therapies, challenges remain, including tumor cell metabolic plasticity, tumor context-dependent responses, and heterogeneity. This review systematically summarizes the molecular structure, physiological functions, and mechanisms of FASN in tumorigenesis, as well as recent advances in targeted therapies. Future directions—including the precise identification of responsive patient populations using spatial transcriptomics, the development of novel combination regimens, and the active exploration of integrative strategies combining traditional Chinese and Western medicine—will facilitate the clinical translation of FASN-targeted therapies and open new avenues for improving the quality of life and prognosis of cancer patients.

ObjectiveTo establish an ultra-performance liquid fingerprint and multi-components determination method for Naomaili granules. To evaluate the quality of different batches by chemometrics， and the anti-neuroinflammatory effects of water extract and main components of Naomaili granules were tested in vitro. MethodsThe similarity and common peaks of 27 batches of Naomaili granules were evaluated by using Ultra performance liquid chromatography （UPLC） fingerprint detection. Ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） technology was used to determine the content of the index components in Naomaili granules and to evaluate the quality of different batches of Naomaili granules by chemometrics. LPS-induced BV-2 cell inflammation model was used to investigate the anti-neuroinflammatory effects of the water extract and main components of Naomaili granules. ResultsThe similarity of fingerprints of 27 batches of samples was > 0.90. A total of 32 common peaks were calibrated， and 23 of them were identified and assigned. In 27 batches of Naomaili granules， the mass fractions of 14 components that were stachydrine hydrochloride， leonurine hydrochloride， calycosin-7-O-glucoside， calycosin，tanshinoneⅠ， cryptotanshinone， tanshinoneⅡ_A， ginsenoside Rb₁， notoginsenoside R₁， ginsenoside Rg₁， paeoniflorin， albiflorin， lactiflorin， and salvianolic acid B were found to be 2.902-3.498， 0.233-0.343， 0.111-0.301， 0.07-0.152， 0.136-0.228， 0.195-0.390， 0.324-0.482， 1.056-1.435， 0.271-0.397， 1.318-1.649， 3.038-4.059， 2.263-3.455， 0.152-0.232， 2.931-3.991 mg∙g^-1， respectively. Multivariate statistical analysis showed that paeoniflorin， ginsenoside Rg₁， ginsenoside Rb₁ and staphylline hydrochloride were quality difference markers to control the stability of the preparation. The results of bioactive experiment showed that the water extract of Naomaili granules and the eight main components with high content in the prescription had a dose-dependent inhibitory effect on the release of NO in the cell supernatant. Among them， salvianolic acid B and ginsenoside Rb₁ had strong anti-inflammatory activity， with IC₅₀ values of （36.11±0.15） mg∙L^-1 and （27.24±0.54） mg∙L^-1， respectively. ConclusionThe quality evaluation method of Naomaili granules established in this study was accurate and reproducible. Four quality difference markers were screened out， and eight key pharmacodynamic substances of Naomaili granules against neuroinflammation were screened out by in vitro cell experiments.

ObjectiveTo investigate the mechanism of action of Jiedu Huayu granules in improving liver injury in mice with acute liver failure （ALF） by observing its effect on a mouse model of ALF after prophylactic administration， and to provide a basis for clinical medication. MethodsA total of 60 specific pathogen-free male C57BL/6J mice were divided into normal group， model group， Jiedu Huayu granules group （JDHY group）， and farnesoid X receptor （FXR） agonist （GW4064） group using a random number table， with 15 mice in each group. The model of ALF was induced by a single intraperitoneal injection of D-galactosamine combined with lipopolysaccharide. The mice in the JDHY group were given prophylactic administration of 0.3 g/mL drug solution of Jiedu Huayu granules by gavage for 3 days before modeling， those in the normal group and the model group were given 0.9% NaCl solution by gavage， and those in the GW4064 group were given intraperitoneal injection of GW4064 for 3 consecutive days before modeling. The mice were sacrificed after modeling， and serum and liver tissue samples were collected. A veterinary automatic biochemical analyzer was used to measure the serum levels of total bilirubin （TBil）， total bile acids （TBA）， gamma-glutamyl transferase （GGT）， alanine aminotransferase （ALT）， and aspartate aminotransferase （AST） in mice from each group； HE staining was used to observe liver pathological changes； RT-PCR was used to measure the mRNA expression levels of FXR， fibroblast growth factor 15 （FGF15）， fibroblast growth factor receptor 4 （FGFR4）， small heterodimer partner （SHP）， and bile salt export pump （BSEP） in mice， and Western blot was used to measure the protein expression levels of FXR， FGF15， FGFR4， SHP， and BSEP. A one-way analysis of variance was used for comparison between groups， and the Dunett method was used for further comparison between two groups. ResultsCompared with the normal group， the model group had significant increases in the serum levels of TBil， ALT， AST， TBA， and GGT （all P<0.01）， and compared with the model group， the JDHY group and the GW4064 group had significant reductions in the serum levels of TBil， ALT， AST， TBA， and GGT （all P <0.01）. HE staining showed that compared with the model group， the JDHY group and the GW4064 group had milder pathological injury， a reduction in the area of hepatocyte necrosis， and alleviation of cellular swelling and edema. Compared with the normal group， the model group had significant reductions in the mRNA and protein expression levels of FXR， FGF15， FGFR4， SHP， and BSEP in liver tissue （all P <0.01）， and compared with the model group， the JDHY group and the GW4064 group had significant increases in the mRNA and protein expression levels of FXR， FGF15， FGFR4， SHP， and BSEP in liver tissue （all P <0.05）. ConclusionJiedu Huayu granules may alleviate liver injury in mice with ALF through the FXR/SHP axis.

ObjectiveTo investigate the protective effect of Xielitang on dextran sulfate sodium （DSS）-induced ulcerative colitis （UC） mice and its possible mechanism. MethodsDSS was used to establish UC model. Sixty mice were randomly divided into a normal group， a model group， a sulfasalazine group （0.6 g·kg^-1）， and low-， medium-， and high-dose Xielitang groups （1.67， 3.34， 6.68 g·kg^-1）. After treatment for 42 d， the colon length was recorded， and the disease activity index （DAI） score was calculated. Enzyme-linked immunosorbent assay （ELISA） was used to detect the serum levels of tumor necrosis factor-α （TNF-α）， interleukin-6 （IL-6）， and interleukin-10 （IL-10）. Hematoxylin-eosin （HE） staining was used to observe the pathomorphological changes of colon. Western blot was used to detect the protein expression of farnesoid X receptor （FXR）， small heterodimer partner （SHP）， liver receptor homolog-1 （LRH-1）， cholesterol 7α-hydroxylase （CYP7A1）， and fibroblast growth factor receptor 4 （FGFR4） in liver and FXR， sodium-dependent bile acid transporter （ASBT）， and fibroblast growth factor 15 （FGF15） in ileum. 16S rRNA sequencing was used to analyze the intestinal flora. Moreover， ultra-high performance liquid chromatography–tandem mass spectrometry was used to detect the bile acid content. ResultsCompared with the normal group， the model group showed significantly decreased colon length， IL-10 content， α-diversity index， abundance of Firmicutes and Lactobacillus， and content of deoxycholic acid （DCA） and lithocholic acid （LCA） （P<0.01）， significantly increased DAI score， IL-6 and TNF-α content， abundance of Bacteroidetes， and the content of cholic acid （CA）， chenodeoxycholic acid （CDCA）， and taurocholic acid （TCA） （P<0.05， P<0.01）， significantly down-regulated protein expression of FXR， SHP， and FGFR4 in liver and FXR， ASBT， and FGF15 in ileum （P<0.01）， and significantly up-regulated protein expression of LRH-1 and CYP7A1 in liver （P<0.01）. In addition， the structure of colonic mucosa was destroyed， and inflammatory cells infiltrated in the model group. Compared with the model group， Xielitang could significantly increase the colon length， IL-10 content， α-diversity index， the abundance of Firmicutes and Lactobacillus， and DCA and LCA content （P<0.05， P<0.01）， decrease DAI score， abundance of Bacteroidetes， and the content of IL-6， TNF-α， CA， CDCA， and TCA （P<0.01）， up-regulate the protein expression of FXR， SHP， and FGFR4 in liver and FXR， ASBT， and FGF15 in ileum （P<0.01）， and down-regulate the protein expression of LRH-1 and CYP7A1 in liver （P<0.01）. The pathological damage of colonic mucosa was obviously alleviated. ConclusionXielitang protects against UC probably by regulating the "intestinal microbiota-bile acid" axis， regulating intestinal flora imbalance， and maintaining bile acid homeostasis.

Objective:To evaluate the strengths and weaknesses of the total payment policy in China′s county medical community (CMC), and to provide decision-making basis for the high-quality development of CMC and its medical security system.Methods:Official websites of China′s provincial and prefectural governments, the Health Commission and the Medical Security Bureau were searched for policies related to total payment in CMC (issued from May 2019 to December 2023), and 10 representative sample policies were selected based on the balance of the temporal and spatial distribution and the completeness of the content. The policy modeling consistency (PMC) index model was used to quantitatively evaluate the sample policies by identifying primary and secondary variables.Results:The PMC index model variables for the total payment policies in CMC included 10 primary variables such as policy nature, policy timeliness, and policy receptors, and 54 secondary variables such as prediction, recommendation, and regulation. The average PMC index score for the 10 sample policies is 6.86, which was generally at a good level, with five policies each of excellent and good grades. In terms of the primary indicators, the policy nature (0.77), policy receptor (0.82) and policy content (0.73) scored highly, while the policy timeliness (0.35), policy synergy (0.54) and guarantee mechanism (0.53) scored lowly. A comparison of the two policies with the highest and lowest scores revealed that the main reasons for the low scores were the single setting of policy objectives, the lack of dynamic monitoring of key indicators and the inadequacy of guarantee mechanisms such as multisectoral collaboration.Conclusions:China′s total payment policy in CMC was generally better, but it still needed to be strengthened in terms of policy timeliness, policy synergy and guarantee mechanism. It was recommended that local governments can optimize policies by comprehensively considering the timeliness of long-medium-and short-term policies, giving full play to the synergistic effects of medical security policies, and improving the multi-dimensional co-management and guarantee mechanism.

Background:Bushen Zhuanggu Formula(BZF),derived from the classic Yougui Pills,has shown favorable clinical efficacy in treating advanced nontraumatic osteonecrosis of the femoral head(NONFH),particularly by promoting bone repair.However,its underlying mechanisms remain unclear.Objective:This study aimed to explore the mechanisms by which BZF promotes bone repair in advanced NONFH.Materials and methods:A total of 518 potential BZF targets were identified from the ETCM v2.0 database.Transcriptomic profiling of clinical cohorts revealed 485 differentially expressed genes in advanced NONFH patients compared to healthy controls.A drug target-disease gene interaction network was constructed to identify candidate BZF targets involved in NONFH pathogenesis.In vivo experiments were conducted to validate the effects of BZF in a rat model of advanced NONFH.Results:Network analysis identified key pathways associated with blood circulation obstruction,immune-inflammatory imbalance,and abnormal bone metabolism.Protein kinase C alpha(PKCA),Ras proto-oncogene(RAS),mitogen-activated protein kinase 3(ERK),ETS proto-oncogene 1(ETS1),and receptor activator of nuclear factor-κB ligand(RANKL)formed a signaling axis implicated in NONFH pathogenesis.BZF treatment alleviated joint inflammation,preserved trabecular bone morphology,reduced bone loss,and promoted bone repair.Mechanistically,BZF significantly downregulated the expression of PKCA,RAS,ERK,ETS1,and RANKL,improved blood circulation,and inhibited osteoclast activation while promoting osteoblast activation.Conclusion:BZF may promote bone repair in advanced NONFH by enhancing blood circulation and modulating the PKC-RAS-ERK-ETS1-RANKL signaling axis,thereby reversing dysregulated bone metabolism.

Objective To analyze the disability level and long-term care needs assessment policies issued by 49 pilot cities in China's long-term care insurance system,providing insights for further improvement of the system.Methods Policy documents related to long-term care insurance,published between June 2016 and December 2024 on official platforms of local governments,the Ministry of Human Resources and Social Security,the National Healthcare Security Administration,and the National Public Service Platform for Standards Information,were retrieved.A comparative analysis was used to summarize and compare the content of these policy texts.Results Currently,there are 49 pilot cities implementing the long-term care insurance system in China.47 cities have issued disability level assessment standards,with 38 cities adopting the trial standards issued by the National Healthcare Security Administration.In 42 pilot cities,the disability level assessment includes indicators such as activities of daily living,cognitive function,and sensory and communication abilities.22 cities have issued policies related to care needs assessment.In most cities,the care needs assessment partially or fully includes indicators from the disability level assessment.Conclusion There is no national uniformity in disability level assessment standards,and the care needs assessment framework needs further improvement.It is recommended to standardize disability level assessment criteria,clearly delineate the boundaries and content of disability level and care needs assessments,and enhance the development of the care needs assessment system.