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Ubiquitin-conjugating enzyme E2 C (UBE2C) plays a carcinogenic role in gastric cancer (GC); yet, its role in cisplatin (DDP) resistance in GC is enigmatic. This study sought to probe into the impact of UBE2C on DDP resistance in GC and its concrete molecular mechanism in GC progression. Bioinformatics analysis was used to analyze differentially expressed mRNAs and predict upstream regulatory molecules in GC. Real-time quantitative reverse transcriptase polymerase chain reaction and western blot were used to detect the expression of UBE2C and MYB proto-oncogene like 2 (MYBL2). Dual luciferase and chromatin immunoprecipitation (ChIP) assays were used to verify the binding relationship. Cell counting kit-8 was used to detect cell viability and calculate IC50 values. Flow cytometry was used to detect the cell cycle. Comet assay was used to detect DNA damage. Western blot was used to detect the expression of DNA loss-related proteins (γ-H2AX, ATM/p-ATM). The knockdown of highly expressed UBE2C in GC cell lines could reduce cell viability, induce G2/M arrest, induce apoptosis, and promote DNA damage and DDP sensitivity. Bioinformatics analysis predicted that the substantially upregulated MYBL2 was an upstream transcription factor in UBE2C. The binding relationship between the UBE2C promoter region and MYBL2 was verified by dual luciferase and ChIP. Overexpression of UBE2C in the rescue experiment was found to reverse the inhibited GC progression and promoted DDP sensitivity brought by the knockdown of MYBL2. In conclusion, the MYBL2/UBE2C regulatory axis may be a potential way to overcome DDP resistance in GC.

Uniflow scavenging opposed-piston two-stroke diesel engine has high power density and thermal efficiency. However, the uniflow scavenging performance control is inflexible and inefficient. In this study, the dual intake channels are proposed. The performance advantages and control methods of dual intake channels are explored by comparing the performance differences between single and dual intake channels under different conditions. The results show that the comprehensive performance of the dual intake channels is better than the single intake channel. Dual intake channels can improve energy efficiency and reduce NOX emissions while maintaining ideal comprehensive performance. Under a single working condition of the dual intake channel, the air supply mass is reduced by 28.4%, and the NO emissions is reduced by 12%. For the dual intake channels, swirl intake channel pressure significantly affects scavenging efficiency, while straight intake channel pressure significantly affects the scavenging speed. Low intake port height ratio α and high straight intake channel pressure are more suitable for high-speed conditions, and high intake port height ratio α and low straight intake channel pressure are more suitable for low-speed conditions. [ABSTRACT FROM AUTHOR]

Background/Objectives: Glioblastoma (GBM) is the deadliest type of brain tumor and photodynamic therapy (PDT) is a promising treatment modality of GBM. However, insufficient photosensitizer distribution in the GBM critically limits the success of PDT. To address this obstacle, we propose tumoritropic neutrophils (NE) as active carriers for photosensitizer delivery to achieve GBM-targeted PDT. Methods: Isolated mouse NE were loaded with functionalized hexagonal boron nitride nanoparticles carrying the photosensitizer chlorin e6 (BNPD-Ce6). In vitro experiments were conducted to determine drug release from the loaded NE (BNPD-Ce6@NE) to mouse GBM cells and consequential photo-cytotoxicity. In vivo experiments were performed on mice bearing intracranial graft GBMs to demonstrate GBM-targeted drug delivery and the efficacy of anti-GBM PDT mediated by BNPD-Ce6@NE. Results: BNPD-Ce6@NE displayed good viability and migration ability, and rapidly released BNPD-Ce6 to co-cultured mouse GBM cells, which then exhibited marked reactive oxygen species (ROS) generation and cytotoxicity following 808 nm laser irradiation (LI). In the in vivo study, a single intravenous bolus injection of BNPD-Ce6@NE resulted in pronounced Ce6 distribution in intracranial graft GBMs 4 h post injection, which peaked around 8 h post injection. A PDT regimen consisting of multiple intravenous BNPD-Ce6@NE injections each followed by one extracranial tumor-directed LI 8 h post injection significantly slowed the growth of intracranial graft GBMs and markedly improved the survival of host animals. Histological analysis revealed massive tumor cell damage and NE infiltration in the PDT-treated GBMs. Conclusions: NE are efficient carriers for GBM-targeted photosensitizer delivery to achieve efficacious anti-GBM PDT. [ABSTRACT FROM AUTHOR]

Water yield in a watershed is mainly affected by both climatic and physiographical factors, but the interaction between different factors still cannot be completely understood. The soil and water assessment tool (SWAT), geographic detector, and natural breaks were integrated to address the impact of different factors on water yield and the identification of important hydrometeorological and underlying surface variables. (1) The significance of precipitation accounted for more than 70% of the total statistics, and its q statistic reached 0.261, which was the main driving factor and contributed an important explanatory power to the spatial variation of water yield. Moreover, the two-factor combination of slope and precipitation has the strongest interactive explanatory power on spatial variation of water yield. (2) The interaction between different meteorological factors has bivariate enhancement and nonlinear enhancement effects on the spatial variation of water yield. However, there is only nonlinear enhancement between land use factors and meteorological factors because the explanatory power of different land use types on water yield is not very prominent, while their explanatory power can be enhanced when interacting with other meteorological factors, especially evaporation. (3) Adding factors does not improve the explanatory power of original single or double factors, indicating that using the SWAT model to delineate subbasins and simulate water yield may homogenize factor attributes, especially peak rainfall, and weaken the explanatory power, and the size of subbasin and distribution of rain gauges make the spatial correspondence between different factor attributes and water yield not entirely consistent. This study can provide a scientific reference for the protection of water resources, the optimization of land use strategy, and the tradeoffs of ecological hydrologic services in semiarid and arid regions. [ABSTRACT FROM AUTHOR]

Guided by well-established theories on student retention, a survey was developed and implemented to collect data about the college experience of STEM students at a four-year research university. Analysis of the survey data confirms ten constructs that captured different aspects of students' academic and social experiences. Among them, academic quality provided by the institution, students' formal academic integration, and motivation for active learning are identified to be the most influential factors to their retention. Different from students in non-STEM majors, financial pressure to fund college education and accessibility to faculty members outside the classroom are not significantly associated with STEM students' intention to depart. The findings also challenge the sociological emphasis on social engagement as the pivotal point for student retention in STEM majors. To improve student persistence in STEM majors, it is suggested the institutional administrators invest in improving faculty members' teaching skills, reducing class sizes, and engaging students in active learning and research projects.

In this study, data collected from 875 college freshman and sophomore students enrolled in a 4-year university in central China are used to examine the applicability and validity of a Chinese version of Holland's Self-Directed Search (SDS) that was adapted in the 1990s. The total sample was randomly divided into two groups. Data from the first half of the sample (n[subscript 1] = 438) were used to analyze the reliability and validity of the adapted SDS, and 52 items were identified for removal due to lack of cross-cultural fit, lack of validity to measure the intended construct, and/or being obsolete due to progress in societal and occupational trends. The SDS before and after item removal were further compared using confirmatory factor analysis with the second half of the sample (n[subscript 2] = 437). Practical implications of this empirical modification approach are discussed. This study contributes to the literature by extending the current discussion about cross-cultural adaptation of Holland's inventories and by suggesting a methodological approach to improve the reliability and validity of adapted assessment tools.

With the development of control technology, the uniflow scavenging opposed-piston (USOP) diesel engine has shown unique advantages in energy savings and emission reductions. Due to the uniflow scavenging process, unstable scavenging performance has become the key problem in the development process of the USOP diesel engine, and the intake structure is an effective method for regulating scavenging performance. This study verifies the simulation model based on experimental data and then analyzes the influence of the intake port structure through simulations. On the one hand, this study explores the interference mechanism and application rules of two structures: composite intake ports and dual independent intake ports. The results show that the external alignment structure should be used under all operating conditions for composite intake ports. For dual independent intake ports, the internal alignment structure should be used at high swirl strength, and the external alignment structure should be used at low swirl strength. On the other hand, the dual independent intake ports matching the dual intake channels can improve scavenging performance while reducing supply power. The conclusion provides a reference for the design of the intake structure of the USOP diesel engine from many aspects. [ABSTRACT FROM AUTHOR]

Based on earlier studies using the 1999 and 2004 National Study of Postsecondary Faculty (NSOPF) data [1, 2], a causal model explaining faculty technology use was constructed. Path analysis was used to test the causal effects of age, gender, highest degree, discipline (health science or not), recent research productivity, and teaching load on faculty use of websites in teaching. Two models, one for faculty from Research I institutions and the other for faculty from Community Colleges, were tested and both models fit the data with satisfying indices. Results confirmed that age, highest degree, and teaching loads influenced technology use directly, but indicated the lack of relationship between research productivity and technology use in teaching. An additional connection is suggested from discipline to teaching load. One important difference between the two models is that the impact of gender and teaching load on research productivity is significant for faculty at Research institutions, but not for faculty at community colleges. The models confirm the consistent and relatively strong relationship of teaching load to faculty technology use. (Contains 2 figures and 2 tables.)