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The equipartition theorem is crucial in classical statistical physics, and recent studies have revealed its quantum counterpart for specific systems. This raises the question: does a quantum counterpart of the equipartition theorem exist for any given system, and if so, what is its concrete form? In this Letter, we employ the Möbius inversion approach to address these questions, providing a criterion to determine whether a system adheres to the quantum counterpart of the equipartition theorem. If it does, the corresponding distribution function can be readily derived. Furthermore, we construct the fermionic version of the criterion in a manner analogous to the bosonic case.

Abstract Background Inadequate DNA damage repair promotes aberrant differentiation of mammary epithelial cells. Mammary luminal cell fate is mainly determined by a few transcription factors including GATA3. We previously reported that GATA3 functions downstream of BRCA1 to suppress aberrant differentiation in breast cancer. How GATA3 impacts DNA damage repair preventing aberrant cell differentiation in breast cancer remains elusive. We previously demonstrated that loss of p18, a cell cycle inhibitor, in mice induces luminal-type mammary tumors, whereas depletion of either Brca1 or Gata3 in p18 null mice leads to basal-like breast cancers (BLBCs) with activation of epithelial-mesenchymal transition (EMT). We took advantage of these mutant mice to examine the role of Gata3 as well as the interaction of Gata3 and Brca1 in DNA damage repair in mammary tumorigenesis. Results Depletion of Gata3, like that of Brca1, promoted DNA damage accumulation in breast cancer cells in vitro and in basal-like breast cancers in vivo. Reconstitution of Gata3 improved DNA damage repair in Brca1-deficient mammary tumorigenesis. Overexpression of GATA3 promoted homologous recombination (HR)-mediated DNA damage repair and restored HR efficiency of BRCA1-deficient cells. Depletion of Gata3 sensitized tumor cells to PARP inhibitor (PARPi), and reconstitution of Gata3 enhanced resistance of Brca1-deficient tumor cells to PARP inhibitor. Conclusions These results demonstrate that Gata3 functions downstream of BRCA1 to promote DNA damage repair and suppress dedifferentiation in mammary tumorigenesis and progression. Our findings suggest that PARP inhibitors are effective for the treatment of GATA3-deficient BLBCs.

Metallic coatings are widely employed to improve the oxidation resistance of superalloys. However, the interdiffusion between the metallic coatings and the superalloys leads to microstructural degradation in both. Some of the underlying degradation mechanisms are still elusive, e.g., the γ′ (Ni3Al) phase depletion in superalloys, where a large amount of γ′ precipitates are dissolved in the γ matrix even though the incoming Al from coatings indeed increases the Al content. Here, we investigated the interdiffusion behavior between the Amdry365 coating and the IN792 superalloy at 1100 °C, using multiple microscopic techniques and thermodynamics calculations. Our results showed an excellent agreement between experiments and thermodynamics simulations, indicating the dominant role of Al on the initial diffusion-induced phase transitions. We proposed the Al-Cr interference effect to account for the pile-up behavior of Cr and the reduced Al content near the coating/superalloy interface. The local phase equilibrium calculations revealed that the γ′ depletion in the superalloy is primarily attributed to the loss of γ′-forming elements, such as Ta and Ti. Our findings opened up an avenue for studies on the superalloy/coating interdiffusion, contributing to reducing this damaging impact.

The number of graduates from China's higher vocational colleges and universities is increasing, and making wise career decisions plays a key role in students' career development. This study is based on the conceptual framework of the Career Self-Management Model of the Social Cognitive Career Theory. This study constructed a model that can improve the quality of career decision-making among college students in higher vocational institutions and explores the effects of career values, career decision self-efficacy, and career goals on career decision-making. Questionnaire data from 654 students attending higher education institutions in China were used. The results showed that both career values and career decision self-efficacy had significant positive effects on career decisions. Moreover, both career decision self-efficacy and career goals played a mediating role. The results demonstrate the applicability of the Career Self-Management Model conceptual framework to the study of career decision-making among college students attending higher education institutions.

Abstract Basal-like breast cancers (BLBCs) are among the most aggressive cancers, partly due to their enrichment of cancer stem cells (CSCs). Breast CSCs can be generated from luminal-type cancer cells via epithelial-mesenchymal transition (EMT). GATA3 maintains luminal cell fate, and its expression is lost or reduced in BLBCs. However, deletion of Gata3 in mice or cells results in early lethality or proliferative defects. It is unknown how loss-of-function of GATA3 regulates EMT and CSCs in breast cancer. We report here that haploid loss of Gata3 in mice lacking p18Ink4c, a cell cycle inhibitor, up-regulates Fra1, an AP-1 family protein that promotes mesenchymal traits, and downregulates c-Fos, another AP-1 family protein that maintains epithelial fate, leading to activation of EMT and promotion of mammary tumor initiation and metastasis. Depletion of Gata3 in luminal tumor cells similarly regulates Fra1 and c-Fos in activation of EMT. GATA3 binds to FOSL1 (encoding FRA1) and FOS (encoding c-FOS) loci to repress FOSL1 and activate FOS transcription. Deletion of Fra1 or reconstitution of Gata3, but not reconstitution of c-Fos, in Gata3 deficient tumor cells inhibits EMT, preventing tumorigenesis and/or metastasis. In human breast cancers, GATA3 expression is negatively correlated with FRA1 and positively correlated with c-FOS. Low GATA3 and FOS, but high FOSL1, are characteristics of BLBCs. Together, these data provide the first genetic evidence indicating that loss of function of GATA3 in mammary tumor cells activates FOSL1 to promote mesenchymal traits and CSC function, while concurrently repressing FOS to lose epithelial features. We demonstrate that FRA1 is required for the activation of EMT in GATA3 deficient tumorigenesis and metastasis.

Summary: Extensive remodeling of the female mammary epithelium during development and pregnancy has been linked to cancer susceptibility. The faithful response of mammary epithelial cells (MECs) to hormone signaling is key to avoiding breast cancer development. Here, we show that lactogenic differentiation of murine MECs requires silencing of genes encoding ribosomal RNA (rRNA) by the antisense transcript PAPAS. Accordingly, knockdown of PAPAS derepresses rRNA genes, attenuates the response to lactogenic hormones, and induces malignant transformation. Restoring PAPAS levels in breast cancer cells reduces tumorigenicity and lung invasion and activates many interferon-regulated genes previously linked to metastasis suppression. Mechanistically, PAPAS transcription depends on R-loop formation at the 3′ end of rRNA genes, which is repressed by RNase H1 and replication protein A (RPA) overexpression in breast cancer cells. Depletion of PAPAS and upregulation of RNase H1 and RPA in human breast cancer underpin the clinical relevance of our findings.

Torsemide is commonly used to relieve edema during the treatment of acute promyelocytic leukemia (APL) with arsenic trioxide (ATO). We explored the effect of torsemide on the plasma concentrations of inorganic arsenic (iAs), monomethylarsonic acid (MMAV) and dimethyarsinic acid (DMAV) in APL patients treated with ATO and clarified its molecular mechanism in rats and cells. The study included 146 APL patients treated with ATO. 60（41.1 %) of these 146 patients were co-administered with torsemide. The treatment of torsemide increased plasma concentrations of iAs (P

The number of graduates from China’s higher vocational colleges and universities is increasing, and making wise career decisions plays a key role in students’ career development. This study is based on the conceptual framework of the Career Self-Management Model of the Social Cognitive Career Theory. This study constructed a model that can improve the quality of career decision-making among college students in higher vocational institutions and explores the effects of career values, career decision self-efficacy, and career goals on career decision-making. Questionnaire data from 654 students attending higher education institutions in China were used. The results showed that both career values and career decision self-efficacy had significant positive effects on career decisions. Moreover, both career decision self-efficacy and career goals played a mediating role. The results demonstrate the applicability of the Career Self-Management Model conceptual framework to the study of career decision-making among college students attending higher education institutions.

The use of aluminiferous coatings profoundly improves the service life of superalloys but leads to microstructural degradation of superalloys and thus loss of mechanical properties. In this study, we modified MCrAlY coatings by adding Ta to reduce the interdiffusion effect on substrate alloys. This strategy was verified by 2000 h/1100 °C oxidation tests in two Ta-containing MCrAlY-IN792 systems. The system with 3.3 wt% Ta MCrAlY exhibits an outstanding resistance to γ′ depletion in the substrate and comparable oxidation property in comparison with a reference system of Ta-free MCrAlY-IN792. Increasing Ta to 7.4 wt% results in reduced oxidation resistance. Thermodynamic simulations revealed the phase-transformation mechanism induced by initial interdiffusion, uncovering the cause of γ′ depletion in the substrate and the mechanism behind improving resistance to γ′ depletion by Ta addition.

Geotechnical survey is an important prerequisite to the construction of offshore wind farms. However, the impact of underwater survey noises has not yet been studied in details. In this paper, we studied transmission of underwater noises from offshore exploratory drilling (OED) at the Xiamen port. The noises were categorized into three types: hammering noises (hammering down of casings, which were 180-mm diameter steel pipes), vibrating noises (vibration of casings that had been hammered down), and drilling noises (generated during the borehole drilling process). We considered the variation in intensity of these three noise types, and set up two fixed and one movable stations to measure and analyze the source and propagation characteristics of these noises. The results indicate that hammering noise is an impulsive sound with a dominant frequency below 10 kHz, and source levels (SLs) of 197.1 dB re 1μPa @ 1 m (rms over 95% energy duration. 1–64,000 Hz) and 212.9 dB re 1μPa @ 1 m (peak). Vibrating and drilling noises are non-impulsive sounds with the fundamental frequencies of 41 Hz and 45 Hz, and SLs of 158.9 dB re 1μPa rms @ 1 m and 155.9 dB re 1μPa rms @ 1 m, respectively. The impact assessment of OED noises on five groups of marine mammals with different audible frequency ranges (Low (LF), High (HF), and Very High (VHF) frequency cetaceans, sirenians (SI), and phocid pinnipeds (PW)) demonstrates that hammering noise can induce a high risk of hearing damage to their hearing, at as far as 300 meters for VHF group, while drilling noise can only induce hearing damage at about 40 meters. Marine mammals are susceptible to behavior alteration, with a detectable distance of 1.9 km from the source, and it is recommended to set a warning zone with a radius of 1.9 km during OED construction.