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IntroductionArithmetic calculation is a fundamental skill for mathematical learning and daily life. However, elementary school students often make errors in practice.MethodsGrounded in the schema theory and the memory retrieval theory of mental arithmetic, this study employs a controlled experiment to investigate the effect of a schema-based method in correcting persistent errors in mental arithmetic, specifically in the context of simple addition operations. The experimental group utilizes a schema-based method to help participants rectify incorrect answers in memory retrieval, while the control group did not receive this treatment.ResultsThe results showed that significant differences emerged between the experimental and control groups in both the post-test performance and the reduction of persistent error count, indicating that the experimental group had rectified incorrect answers in memory; and persistent errors in simple addition were indeed caused by interference from incorrect answers during memory retrieval; and the schema-based method proves to be effective.DiscussionThe findings of this study contribute to enhancing practical mental arithmetic instruction, assisting students in correcting relevant errors, and improving their mental arithmetic abilities. Not only does it offer directive guidance for teaching practices, but it also provides an enlightening reference for promoting innovative teaching methods.

Abstract Classical Chinese poetry, as an indispensable part of China′s national culture, provides valuable resources for improving literary literacy and fostering patriotism among primary and secondary school students. This study, based on cognitive schema migration theory, investigated the effect of a "schema-associated mnemonic method" on the memory efficiency and retention of classical Chinese poetry memorization among the students. Through a controlled experiment, the results revealed that the experimental group (n = 63) outperformed the control one in memorizing classical poetry with higher memory efficiency and retention, which indicates the sustainable application prospects of the method in primary and secondary education. The findings of this research can provide beneficial insights for the effective integration of classical Chinese poetry teaching and educational technologies.

Skillful utilization of mental arithmetic can significantly improve students' mathematical computation ability. However, it was observed that primary school students often resort to reiterating the process of written arithmetic in their minds during mental arithmetic, which is not conducive to their numerical ability improvement. This paper devises a set of graphic teaching aids for primary school students' mental arithmetic improvement based on mental arithmetic strategies, schema theory, and working memory. To validate the effectiveness of schema teaching in enhancing mental arithmetic ability among primary school students, a controlled experiment was conducted with two groups of third-grade students randomly selected from a primary school in Jingshan City. The results, obtained through descriptive statistical analysis and the multitrait-multimethod approach (MTMM), indicated that the experimental group (n = 52) demonstrated significant improvements in speed, accuracy, and stability in mental addition and subtraction after a 14-day instruction period in schema teaching. This study offers a potent mental arithmetic teaching strategy for elementary mathematics education, which can lead to a comprehensive enhancement of students' mental calculation abilities. It also holds promise for inspiring innovative teaching methodologies in primary and secondary mathematics education in the future.

Bi2Te3 is a thermoelectric material with high thermoelectric conversion efficiency near room temperature. The control of its components is an effective method to improve the thermoelectric properties of Bi–Te based materials. In this paper, seven-layer Bi–Te thin films with Te content ranging from 36.29% to 77.29% were deposited on non-rotating glass substrates by co-sputtering and the samples were rapidly thermally annealed in a nitrogen atmosphere. The films were characterized by x-ray diffraction, scanning electron microscopy, and Hall effect measurement methods, and the effects of the components on the film morphology and thermoelectric properties were investigated. The results showed that the films were composed of mainly Bi2Te3 after annealing. As the Te element content increased, the grain size in the film surface first increased and then decreased, the layers between the interfaces became less obvious, and the number of voids decreased. Subsequently, thin films with Te content between 60% and 75% were deposited on a rotating substrate; the thermoelectric properties were relatively high and stable after annealing. A film with Te content of 69.29% had a good crystallization quality and large grain size with a maximum power factor of 8.17 µW/(K2 cm) after annealing at 350 °C for 17 min.

Heat sources on rectangular plates with double-sided convective cooling are a common application of heat transfer in electronic packaging. However, it is considerably difficult to obtain analytical solutions for improving thermal performance because of the mixed boundary conditions on a plate’s upper surface. In this study, mixed boundary conditions were adjusted twice. Based on the method of separation of variables, a new analytical model was established and used to calculate the thermal performance of a random application case, including temperature distribution, thermal spreading resistance, and total thermal resistance. The results indicated that accurate analytical solutions can be obtained with few computing resources when more than 30 terms are used in each of single and double summations with a total mesh number of 196 in the heat source region. Subsequently, a series of thermal performances were calculated for random application cases and simulations were also conducted using the commercial software Icepak to offer a reference. The data comparisons revealed that the analytical model is able to calculate the temperature values at arbitrary point coordinates accurately over wide ranges of a plate’s thermal conductivity and heat transfer coefficient.

Basic research on chronic rhinosinusitis (CRS) has advanced significantly in the past two decades, yet a comprehensive understanding of its pathogenic mechanisms remains elusive. Concurrently, there is a growing interest among scientists in exploring the involvement of autophagy in various human diseases, including tumors and inflammatory conditions. While the role of autophagy in asthma has been extensively studied in airway inflammatory diseases, its significance in CRS with or without nasal polyps (NPs), a condition closely linked to asthma pathophysiology, has also garnered attention, albeit with conflicting findings across studies. This review delves into the role of autophagy in CRS, suggesting that modulating autophagy to regulate inflammatory responses could potentially serve as a novel therapeutic target.

We report a case of Klebsiella pneumoniae invasive liver abscess syndrome (KPILAS) with endophthalmitis-caused blindness as the first symptom after enema. The patient had diabetes, and his blood glucose was poorly controlled. She developed hematuria after four enemas for cosmetic purposes and later became blind. The eye discharge was cultured, which revealed a Klebsiella pneumoniae infection. B ultrasound did not show liver lesions, but computed tomography exhibited abscesses in the right lobe of the liver. Magnetic resonance imaging of the head indicated abscesses. These confirmed the diagnosis of invasive liver abscess syndrome. The patient was given ophthalmic and systemic anti-infection treatments, and her condition was effectively controlled. Unfortunately, the diseased eye still needed to be removed. This case underlines the necessity of avoiding unnecessary risky procedures (such as enemas) in vulnerable populations, the importance of early detection of invasive liver abscess syndrome, and the advantage of computed tomography in detecting liver abscesses.

We reported a case of a 68-year-old man who presented with recurrent fever and multiorgan dysfunction. His significantly elevated procalcitonin and C-reactive protein levels indicated recurrent sepsis. However, no focus of infection and no pathogens were identified through a variety of examinations and tests. Although the increase of creatine kinase was less than five times the upper limit of normal value, the diagnosis of rhabdomyolysis secondary to adrenal insufficiency resulting from primary empty sella syndrome was finally made, as supported by serum myoglobin elevation, serum cortisol, and adrenocorticotropic hormone deficiency, bilateral adrenal atrophy on computed tomography, and empty sella on magnetic resonance imaging. After the glucocorticoid replacement treatment, the patient's myoglobin gradually returned to normal range, and his condition continued to improve. Rhabdomyolysis resulting from a rare cause may be misdiagnosed as sepsis in patients who present with increased procalcitonin levels.

To address the problem of heavy metal contamination of lead smelting slag such as As, Zn, Pb and Cd in the Sishuizhuang area of Gejiu City, Yunnan Province, oily sludge pyrolysis residue was used to stabilize them to reduce the leaching toxicity of these heavy metals. The pyrolysis residue is a carbonaceous composite containing a large amount of nano-FeS, Fe1-xS, CaS, etc., which has the potential to stabilize the heavy metals in lead slag. It was shown that heavy metals As, Zn, Pb and Cd in lead slag could be efficiently and synchronously adsorbed on the surface of pyrolysis residue, reducing the leaching toxicity of these heavy metals in lead slag. When the weight ratio of pyrolysis residueis is 4% and liquid-solid ratio is 10:100, the leaching concentrations of As, Zn, Pb and Cd in the lead slag can be reduced from 0.7202, 3.5120, 0.3800 and 0.0456 mg/L to 0.0714, 0.1668, 0.0262 and 0.0038 mg/L, respectively, which are lower than the surface water environmental quality standards (GB 3838—2002 ) in the Ⅳ level limit value. The reduction of leaching concentration of As, Zn, Pb and Cd in lead slag is due to the reaction of As in lead slag with Ca2+ and Fe2+ on the surface of pyrolysis slag to produce stable calcium arsenate and ferrous arsenate in situ, and the reaction of Zn2+, Pb2+ and Cd2+ in lead slag with S2- on the surface of pyrolysis slag to produce stable ZnS, PbS and CdS in situ, which improves the stability of As, Zn, Pb and Cd in lead slag.

BackgroundMetagenomic next-generation sequencing (mNGS) is a promising technology that allows unbiased pathogen detection and is increasingly being used for clinical diagnoses. However, its application in urinary tract infection (UTI) is still scarce.MethodsThe medical records of 33 patients with suspected UTI who were admitted to the Second Hospital of Tianjin Medical University from March 2021 to July 2022 and received urine mNGS were retrospectively analyzed. The performance of mNGS and conventional urine culture in diagnosing infection and identifying causative organisms was compared, and the treatment effects were evaluated in terms of changes in urinalyses and urinary symptoms.ResultsIn the detection of bacteria and fungi, mNGS detected at least one pathogen in 29 (87.9%) cases, including 19 (57.6%) with positive mNGS but negative culture results and 10 (30.3%) with both mNGS and culture positive results. The remaining 4 (12.1%) patients were negative by both tests. Overall, mNGS performed better than culture (87.9% vs. 30.3%, P < 0.001). Within the 10 double-positive patients, mNGS matched culture results exactly in 5 cases, partially in 4 cases, and not at all in 1 case. In addition, mNGS detected a broader pathogen spectrum, detecting 26 species compared to only 5 species found in culture. The most abundant bacteria detected by mNGS was Escherichia coli, detected in 9 (27.2%) patients. All anaerobic bacteria, Mycobacterium Tuberculosis and all mixed pathogens were detected by mNGS. The final clinical diagnosis of UTI was made in 25 cases, and the sensitivity of mNGS was significantly higher than culture (100.0% vs 40.0%; P < 0.001) when using the diagnosis as a reference standard; the positive predictive value, negative predictive value and specificity were 86.2%, 100% and 50.0%, respectively. Importantly, targeted antibiotic therapy based on mNGS resulted in significant improvement in urinalyses and urinary symptoms in patients.ConclusionsmNGS is a technology that has shown clear advantages over culture, particularly in the context of mixed infections and UTIs that are difficult to diagnose and treat. It helps to improve the detection of pathogens, guide changes in treatment strategies, and is an effective complement to urine culture.

The development of phytoremediation technology is constrained by gentle phytoextraction efficiency and slow biomass accumulation. In this study, a combined remediation of pioneer plants and solid waste towards Cd- and As-contaminated farmland soil was explored. Pioneer plants Cynodon dactylon and two material formulas (Steel slag (SS):pyrolusite (PY):ferrous sulfide (FS) = 3:3:2 or 1:2:8) were used in pot experiments. The DTPA method was used to extract the bioavailable heavy metals from soil, and then, the reduction rates of the bioavailable heavy metals were calculated. After harvesting plants, data of moisture content, biomass, root length and plant height were obtained. The remediation effect was evaluated according to the above indexes. The experimental results showed that the remediation effect of Bidentis pilosa was better than that of Cynodon dactylon. The addition of solid waste material significantly reduced the content of bioavailable Cd and As in soil by 97.73% and 53.54%, respectively. Suitable wastes may be a potential addition to heavy metal contaminated soils to promote phytoremediation of heavy metals.

Pyrolysis residue, with the porous structure similar to activated carbon, was proposed as a material to remove heavy metals with low levels from synthetic flotation wastewater in the work. The effects of the dosage on removal efficiency, adsorption kinetics and isotherms were studied. The adsorption mechanism was also discussed. The results showed that pyrolysis residue could remove effectively Cd2+, Pb2+ and Cu2+ from the flotation solution and increase simultaneously its effluent pH. The removal efficiency of Cd2+, Pb2+ and Cu2+ was 99.3, 98.9 and 99.4%, and the corresponding solution pH was 9.79, 9.12 and 8.45 when pyrolysis residue dosages was 1, 0.8 and 0.8 g/L with same 20 mg/L concentrations of Cd2+, Pb2+ and Cu2+ and natural synthetic solution pH, respectively. The pseudo-second-order rate constant (k2) and the qmax of Cd2+, Pb2+and Cu2+ were 0.05, 0.03, 0.04 g/(mg·min) and 106.16, 140.65, 128.04 mg/g. Heavy metals was mainly removed by formation of stable metal sulfides and hydroxides on the surface. The above results have uncovered that pyrolysis residue was viable for removal of heavy metals with low levels from flotation wastewater for the first time.

Purpose: Chemotherapy is the clinically recommended treatment for patients with operable metaplastic breast carcinoma (MBC); however, its impact remains controversial. This study investigated the possible role of chemotherapy in the treatment of MBC.Methods: The Surveillance, Epidemiology, and End Results (SEER) database was used to identify the operable MBC patients. The competing risk analysis along with the propensity score matching (PSM) method was performed to evaluate the effect of chemotherapy. Moreover, a competing risk nomogram was built to identify prognosis in patients with MBC.Results: Of the 1137 patients with MBC, 775 received chemotherapy and 362 did not receive chemotherapy. The 5-year cumulative incidence of breast cancer-specific death (BCSD) showed similar outcomes in both the Chemo and No-Chemo groups (21.1 vs. 24.3%, p = 0.57). Chemotherapy showed no apparent association with BCSD (HR, 1.07; 95% CI, 0.72–1.60; p = 0.72), even after subgroup analysis or PSM. Race, tumor size, lymph node status, and radiation were identified as the significant factors for MBC after a penalized variable selection process. In addition, a competing risk nomogram showed relatively good accuracy of prediction with a C-index of 0.766 (95% CI, 0.700–0.824).Conclusion: Our findings demonstrated that chemotherapy did not improve BCSD for operable MBC patients. Thus, it may indicate the need to reduce exposure to the current chemotherapy strategies for patients with resectable MBC. Additionally, some novel treatment strategies are required urgently to identify and target the potential biomarkers.

In this paper, a new method for the comprehensive recovery and recycle of jarosite residues (JR) is proposed. By direct reduction followed by magnetic separation, lead, zinc and iron are separated and recovered from JR and sulfur is fixed. The non-magnetic tails (NMT) of the magnetic separation is used for removing of Cd, As and Pb heavy metal ions from acidic wastewater of zinc hydrometallurgy. Test work results showed that the volatilization rates of lead and zinc were 96.97% and 99.89%, respectively, the sulfur fixation rate with CaO was 98.91% under optimal conditions of reduced roasting at 1523 K for 60 min. A magnetic iron concentrate was obtained containing 95.68% iron at a recovery of 76.26% by grinding-magnetic separation process. The removal rates of Cd, As and Pb ions were 99.98%, 93.75% and 99.80% respectively. The content of Cd, As and Pb ions in the treated wastewater met the emission standards at 120 g/L NMT dosage and for a contact time of 90 mins. The proposed method is considered as an environmentally-friendly and efficient approach to the comprehensive recovery and recycle of JR and the removal of toxic cadmium, arsenic and lead ions from acidic wastewater of zinc hydrometallurgy.

To dispose of arsenic-containing tailings with low carbon and high efficiency, sodium sulphate (Na2SO4), sodium hydroxide (NaOH), calcium nitrate Ca(NO3)2 and calcium hydroxide Ca(OH)2 were independently added to metallurgical slag-based binder (MSB) solidification/stabilisation (S/S)-treated tailings (MSTs) to enhance the MST arsenic S/S performance. Results showed that only Ca(OH)2 could increase the unconfined compressive strength of MST from 16.3 to 20.49 MPa and decrease the leachate As concentration from 31 μg/L to below 10 μg/L. Na3AsO4·12H2O and NaAsO2 were used to prepare pure MSB paste for mechanism analysis. The results of microstructure analyses showed the high specific surface area and amorphous properties of calcium–sodium aluminosilicate hydrate facilitated the adsorption or solid-solution formation of As(V) and As(III). As(V) formed an inner-sphere complex in ettringite, whereas As(III) formed an outer-sphere complex, and the relatively larger size and charge of As(V) compared with SO42− restrict substitution inside channels without affecting the ettringite structure under high loading of As(V). The added Ca(OH)2 promoted the hydration reaction of MSBs and facilitated the formation of a Ca–As(V) precipitate with low solubility, from Ca4(OH)2(AsO4)2·4H2O (Ksp = 10−27.49) to Ca5(AsO4)3(OH) (Ksp = 10−40.12). This work is beneficial for the application of cement-free MSB in the S/S process.