ObjectiveTo systematically compare the differential regulation of the maternal-fetal interface cell lineages and communication networks in the CBA/J×DBA/2 mouse model of recurrent pregnancy loss （RPL） by the two classic therapeutic methods-tonifying the kidney to stabilize the fetus and invigorating the spleen to stabilize the fetus （Shoutai Wan， Juyuan Jian）-of traditional Chinese medicine （TCM） at the single-cell resolution and clarify their modern scientific connotations. MethodsFemale non-pregnant CBA/J mice were caged with male BALB/c （blank group） and DBA/2 （modeling group） mice separately. Pregnant mice in the modeling group were randomly grouped as follows： high/low-dose Shoutai Wan， high/low-dose Juyuan Jian， model （RPL）， and positive control （dydrogesterone）， with 10 mice in each group. Starting from the day after the detection of the vaginal plug， mice were administrated with drugs or an equal volume of normal saline by gavage for 10 consecutive days. After the intervention， the following indicators were measured. ① Macroscopic evaluation： general conditions， uterine wet weight， embryo loss rate， four coagulation parameters ［prothrombin time （PT）， activated partial thromboplastin time （APTT）， fibrinogen （FIB）， and thrombin time （TT）］， and peripheral blood estradiol （E₂） and progesterone （Pg） levels. The decidua with embryos was stained with hematoxylin-eosin （HE） and evaluated by transmission electron microscopy （TEM）. The expression of B-cell lymphoma-2 （Bcl-2）， vascular endothelial growth factor （VEGF）， angiotensin Ⅱ （AngⅡ）， matrix metalloproteinase-2 （MMP-2）， interleukin-6 （IL-6）， leukemia inhibitory factor （LIF）， CXC chemokine ligand 12 （CXCL12）， and microtubule-associated protein 1 light chain 3 homolog （LC3）Ⅰ/Ⅱ was quantified by Western blot. ② Mechanism analysis at the single-cell level： The decidua with embryos from the blank， model， high-dose Shoutai Wan， and high-dose Juyuan Jian groups （6 mice per group， with 3 single-cell samples per group， totaling 24 mice） were analyzed by the BD Rhapsody™ platform， and the whole-cell atlas was drawn by uniform manifold approximation and projection （UMAP） dimensionality reduction clustering combined with the single-cell mouse cell atlas （scMCA）. The differentially expressed genes （DEGs） and cell interaction networks were analyzed via Gene Ontology （GO）， Kyoto Encyclopedia of Genes and Genomes （KEGG）， and CellChat， and the protein-protein interaction （PPI） map of subtype cells was constructed. The CytoTRACE pseudo-temporal analysis was performed to explore the developmental trajectories of core immune cells （natural killer cells， NK cells） from maternal and fetal sources. Results① Pathological and Western blot results indicated that compared with the blank group， the RPL group showed an increase in the embryo loss rate （P<0.01）， down-regulated expression of Bcl-2， LIF， MMP-2， and Vegf in the decidua with embryos （P<0.05）， up-regulated protein levels of CXCL-12， AngⅡ， and IL-6 （P<0.05）， blocked angiogenesis， apoptosis-inflammation imbalance， and coagulation dysfunction. Both prescriptions dose-dependently reduced the abortion rate and restored the angiogenesis-inflammation balance， and Shoutai pill showed superior performance in restoring the E₂ level to the Pg level （P<0.05）. ② Single-cell transcriptome analysis indicated that compared with the blank group， the RPL group showed differences in multiple key cell populations such as decidual cells， trophoblast cells， endothelial cells， erythroblasts， NK cells， and macrophages at the maternal-fetal interface. Immunity and angiogenesis were the key links in RPL. Compared with the RPL group， high-dose Shoutai Wan reversed the changes of NK cells in the embryonic layer （upregulating the mRNA levels of 17 genes and downregulating the mRNA levels of 29 genes） and macrophages （upregulating the mRNA levels of 117 genes and downregulating the mRNA levels of 53 genes） through the regulation of gene expression. High-dose Shoutai pill regulated the immune cells to affect unfolded proteins， cell adhesion， and programmed cell death， thereby promoting decidualization and angiogenesis and modulating embryo-membrane development. High-dose Juyuan Jian regulated the key subgroups of NK cells （up-regulating the mRNA levels of 9 genes and down-regulating the mRNA levels of 17 genes） and macrophages （up-regulating the mRNA levels of 110 genes and down-regulating the mRNA levels of 81 genes）， which affected decidual inflammation and apoptosis and intervened in glycolysis. ③ The pseudo-temporal analysis and communication network indicated that the communication frequency of the RPL group decreased. High-dose Shoutai Wan restored maternal-fetal tolerance through pathways such as NKG2D， CDH5， GDF， and FASLG. High-dose Juyuan Jian enhanced the IL-6/LIFR/JAK/signal transducer and activator of transcription 3 （STAT3） and desmosome/SEMA6/tumor necrosis factor-like weak inducer of apoptosis （TWEAK） signaling to improve endometrial receptivity. The RPL group showed an increased proportion of toxic dNK7， a decreased proportion of reparative dNK4， and blocked embryo fNK1. High-dose Shoutai Wan down-regulated dNK7 and up-regulated dNK4. High-dose Juyuan Jian inhibited the terminal differentiation of dNK7 and up-regulated LILRB1， thus restoring the balance of cytotoxicity and repair. ConclusionBoth the kidney-tonifying and spleen-invigorating methods are effective in treating RPL. NK and macrophages are the key immune cells in the interaction between the embryo and the membrane. The kidney-tonifying method （Shoutai Wan） has an advantage in regulating the phenotypes of unfolded protein， cell adhesion， and programmed cell death， and shows expression characteristics closer to the physiological state in the regulation of NKG2D and CDH5 signals. The spleen-invigorating method （Juyuan Jian） has an advantage in regulating epithelial-mesenchymal transition （EMT）， angiogenesis， and glycolysis and shows higher communication intensity in the IL-6 and LIFR pathways.

Objective: To establish a method for determining the molecular weight and molecular weight distribution of Poly(Lactide-co-Glycolide Acid) (PLGA) using Size Exclusion Chromatography-Refractive Index-Multiangle Laser Light Scattering (SEC-RI-MALLS) and Size Exclusion Chromatography-Refractive Index (SEC-RID), and to compare the results obtained from these two methods.
Methods: For SEC-RI-MALLS, tetrahydrofuran was used as the mobile phase, Shodex GPC KF-803L was employed as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, and an injection volume of 100 μL. For SEC-RID, tetrahydrofuran was also used as the mobile phase, Agilent PLgel 5 μm MIXD-D was used as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, differential detector temperature at 35 ℃, and an injection volume of 20 μL. The molecular weight and molecular weight distribution were calculated using Agilent’s GPC software. The newly established methods were validated methodologically, and the molecular weight and molecular weight distribution of 13 batches of samples were determined.
Results: The precision, accuracy, stability, and repeatability tests for SEC-RI-MALLS showed RSD values of 1.35%, 1.58%, 1.53%, and 1.26%, respectively. The SEC-RID method exhibited good linearity (r=0.999 9), with RSD values for precision, accuracy, stability, and repeatability tests (n=6) of 2.05%, 1.62%, 1.30%, and 2.97%, respectively. The results obtained from SEC-RI-MALLS were lower than those from SEC-RID, and the molecular weight distribution coefficient was smaller, but the results from the paired T-test performed with the value measured by SEC-RID method and the value measured by SEC-RI-MALLS method multiplied a conversion coefficient of 1.5 showed no significant difference between the two methods.
Conclusion: Both methods are stable and reliable, and can be used for the determination of PLGA molecular weight and molecular weight distribution based on the specific situations.

Objective: To analyze the change trends in the body shape indicators and proportions of students in Harbin from 2010 to 2024, and to investigate ergonomic compatibility of functional dimensions of school desks and chairs with current student shape indicators, so as to provide a reference for revising furniture standards of desks and chairs. Methods: Between September and November of both 2010 and 2024, a combination of convenience sampling and stratified cluster random sampling was conducted across three districts in Harbin, yielding samples of 6 590 and 6 252 students, respectively. Anthropometric shape indicators cluding height, sitting height, crus length, and thigh length-and their proportional changes were compared over the 15-year period. The 2024 data were compared with current standard functional dimensions of school furniture. The statistical analysis incorporated t-test and Mann-Whitney U- test. Results: From 2010 to 2024, average height increased by 1.8 cm for boys and 1.5 cm for girls; sitting height increased by 1.5 cm for both genders; crus length increased by 0.3 cm for boys and 0.4 cm for girls; and thigh length increased by 0.5 cm for both genders. The ratios of sitting height to height, and sitting height to leg length increased by less than 0.1 . The difference between desk chair height and 1/3 sitting height ranged from 0.4-0.8 cm. Among students matched with size 0 desks and chairs, 22.0% had a desk to chair height difference less than 0, indicating that the desk to chair height difference might be insufficient for taller students. The differences between seat height and fibular height ranged from -1.4 to 1.1 cm; and the differences between seat depth and buttock popliteal length ranged from -9.8 to 3.4 cm. Among obese students, the differences between seat width and 1/2 hip circumference ranged from -20.5 to -8.7 cm, while it ranged from -12.2 to -3.8 cm among non obese students. Conclusion Current furniture standards basically satisfy hygienic requirements; however, in the case of exceptionally tall and obese students, ergonomic accommodations such as adaptive seating allocation or personalized adjustments are recommended to meet hygienic requirements.

ObjectiveTo investigate the effects of foliar fertilizer of nano-calcium carbonate and calcium nitrate tetrahydrate on the agronomic traits， carbohydrate and endogenous hormone contents of Dendrobium officinale planted for 1 year under greenhouse cultivation， in order to provide scientific basis for fertilization to improve the yield and quality of D. officinale. MethodsSingle-factor experimental design was adopted. Starting from early spring， D. officinale was treated with foliar spraying according to corresponding fertilizers. Three treatment groups were established based on different fertilizers， namely， a blank group（clear water）， a nano-calcium carbonate group（0.727 g·L^-1 nano-calcium carbonate water-soluble fertilizer）， and a calcium nitrate tetrahydrate group（1.091 g·L^-1 calcium nitrate tetrahydrate water-soluble fertilizer）. The frequency of spraying was three times per month， and the entire treatment process lasted for nine months. The effects of various treatments on the traits and relative chlorophyll content of D. officinale were dynamically monitored. Sampling was conducted at three specific time points：August 2， 2023， September 8， 2023， and November 1， 2023， respectively. The contents of glucose and mannose in D. officinale stems were determined by high performance liquid chromatography（HPLC）， the content of soluble sugars in D. officinale stems and leaves was determined by phenol method， and enzyme-linked immunosorbent assay（ELISA） was used to detect the concentrations of cytokinin and auxin. ResultsCompared with the blank group， the treatments with nano-calcium carbonate and calcium nitrate tetrahydrate could significantly increase stem length， stem node number， leaf number， and tiller number. Among them， during the harvesting period in November， the stem length and tiller number， which are indicators related to the yield of D. officinale， increased by 60.85% and 19.23% after treatment with calcium nitrate tetrahydrate， and by 32.54% and 28.85% after treatment with nano-calcium carbonate， respectively. Compared with the blank group， treatments with nano-calcium carbonate and calcium nitrate tetrahydrate could promote the accumulation of sucrose in the stems and leaves of D. officinale to varying degrees， as well as the accumulation of polysaccharides， mannose， and glucose in the stems. In addition， nano-calcium carbonate treatment also facilitated the accumulation of fructose in the stems and leaves of D. officinale. Specifically， during the harvesting period in November， polysaccharides and mannose， which were the main active ingredients in D. officinale stems， increased by 28.48% and 29.36% after treatment with calcium nitrate tetrahydrate， and by 39.91% and 82.62% after treatment with nano-calcium carbonate， respectively. In addition， compared with the blank group， the concentrations of auxin in the stems and leaves of D. officinale were significantly increased after treatment with calcium nitrate tetrahydrate（P<0.05）. Similarly， the concentrations of cytokinin and auxin in the stems of D. officinale were also elevated after treatment with nano-calcium carbonate. Correlation analysis further indicated that elongation growth and tillering of D. officinale stems after foliar spraying of nano-calcium carbonate and calcium nitrate tetrahydrate might be related to the accumulation of carbohydrates in the stems and leaves and the synergistic effect of auxin and cytokinin. ConclusionIn production practice， spraying nano-calcium carbonate and calcium nitrate tetrahydrate can promote the accumulation of cytokinin， auxin， and carbohydrate contents in the stems and leaves of D. officinale， and promote tillering and elongation growth of the stems.

Objective: To analyze the disease burden of chronic obstructive pulmonary disease (COPD) and changes in its risk factors among residents in Zhejiang Province from 1990 to 2021, so as to identify key priorities for COPD prevention and control. Methods: Data on COPD mortality and disability-adjusted life years (DALY) for residents in Zhejiang Province from 1990 to 2021 were collected from the Global Burden of Disease (GBD) 2021 database. Standardized mortality and standardized DALY rate were calculated using the GBD 2021 world population standard structure. Premature mortality was computed via the life table method. The average annual percent change (AAPC) was applied to analyze trends in COPD mortality, DALY rate, and premature mortality. Changes in deaths of COPD risk factors were evaluated using population attributable fraction (PAF). Results: From 1990 to 2021, the standardized COPD mortality in Zhejiang Province decreased from 272.40/100 000 to 70.56/100 000 (AAPC=-4.395%), and the standardized DALY rate declined from 4 167.37/100 000 to 1 071.89/100 000 (AAPC=-4.396%). Similar downward trends were observed in both males (AAPC=-3.933%, -4.173%) and females (AAPC=-4.785%, -4.480%), all P<0.05. Crude mortality and DALY rates increased with age, and the crude mortality and DALY rates of various age groups in Zhejiang Province showed decreasing trends from 1990 to 2021 (all P<0.05). The premature mortality declined from 4.37% to 0.60% from 1990 to 2021 (AAPC=- 6.206%), with consistent trends across males and females (AAPC=- 6.144%, - 6.379%, all P<0.05). From 1990 to 2021, particulate matter pollution showed the largest reduction in PAF (- 56.76%), while ambient ozone pollution had the largest increase (103.07%) in Zhejiang Province. By 2021, smoking became the leading risk factor for deaths of COPD (PAF=43.32%). Conclusions The standardized mortality, standardized DALY rate, and premature mortality for COPD show consistent declining trends in Zhejiang Province from 1990 to 2021. However, risk factors such as smoking and ambient ozone pollution require intensified focus to further reduce disease burden of COPD.