Uniaxial Compression Fractal Damage Constitutive Model of Rock Subjected to Freezing and Thawing

Mechanical properties of the rock in the cold regions are often affected by freeze-thaw cycles and loads. It is of great theoretical significance and engineering value to establish a uniaxial compression damage constitutive model of the rock under freeze-thaw cycles that can reflect the relationship between macroscopic and mesoscopic structural damage. In this paper, macroscopic and mesoscopic methods are combined with statistical methods to quantitatively analyze the damage degree of rock under freeze-thaw cycles and loads. Combined with the fractal features of the macroscopic image of the section, a fractal damage constitutive model considering the residual strength of rock is established. In addition, the model is subsequently verified by the experiment. The experiment shows that the mechanical properties of rocks subjected to freeze-thaw cycles and loads are determined by freeze-thaw damage variables, load damage variables, and their coupling effects. As the number of freeze-thaw cycles increases, the uniaxial compressive strength and elastic modulus of rocks decrease, and peak strain increases. By using the fractal dimension of the compression fracture surface as a bridge considering the residual strength of the rock, the constitutive model can better reflect the compaction stage, elastic deformation stage and plastic deformation stage of the uniaxial compression process of the freeze-thaw rocks

Epigenetics in ovarian cancer: premise, properties, and perspectives.

Malignant ovarian tumors bear the highest mortality rate among all gynecological cancers. Both late tumor diagnosis and tolerance to available chemical therapy increase patient mortality. Therefore, it is both urgent and important to identify biomarkers facilitating early identification and novel agents preventing recurrence. Accumulating evidence demonstrates that epigenetic aberrations (particularly histone modifications) are crucial in tumor initiation and development. Histone acetylation and methylation are respectively regulated by acetyltransferases-deacetylases and methyltransferases-demethylases, both of which are implicated in ovarian cancer pathogenesis. In this review, we summarize the most recent discoveries pertaining to ovarian cancer development arising from the imbalance of histone acetylation and methylation, and provide insight into novel therapeutic interventions for the treatment of ovarian carcinoma

Culture Change and Affectionate Communication in China and the United States: Evidence From Google Digitized Books 1960–2008

Humans are born with the ability and the need for affection, but communicating affection as a social behavior is historically bound. Based on the digitized books of Google Ngram Viewer from 1960 through 2008, the present research investigated affectionate communication (AC) in China and the United States, and its changing landscape along with social changes from collectivist to individualistic environments. In particular, we analyzed the frequency in terms of verbal affection (e.g., love you, like you), non-verbal affection (e.g., hug, kiss), and individualism (indicated by the use of first-person singular pronouns such as I, me, and myself) in Chinese and American books. The results revealed an increasing trend for AC in recent decades, although the frequency of affection words was lower in Chinese than in American books. Further, individualism was positively related to the frequency of affection words in both Chinese and American books. These results demonstrate the effect of cultural changes on AC, in that affection exchange becomes popular in adaptation to individualistic urban environments. These findings exemplify a cross-cultural difference in the expression of love and the cultural universality of social change in Eastern and Western societies

Low-Load Blood Flow Restriction Squat as Conditioning Activity Within a Contrast Training Sequence in High-Level Preadolescent Trampoline Gymnasts

[Abstract] To investigate the effects of implementing low-load blood flow restriction exercises (LL-BFRE) instead of high-load exercises (HL-RE) in a contrast training program on strength and power performance of high-level young gymnasts. Fifteen high-level pre-pubescent trampoline gymnasts (national level, Tanner Stage II, intermediate experience in strength training) were divided into two groups to complete the same structure of a ten-week contrast strength training program differing only in the configuration of the first resistance exercise of the contrast sequence. The LL-BFRE group (n = 7, four girls, 13.9 ± 0.4 y) performed the first resistance exercise of the contrast with LL-BFRE (20%–30% 1RM, perceived pressure of 7 on a scale from 0 to 10). The HL-RE group (n = 8, four girls, 13.8 ± 0.5 y) trained the first resistance exercise of the contrast sequence with moderate-to-high load (60%–85% 1RM). Before and after the training period, isometric mid-thigh pull (IMTP), squat jump (SJ), counter movement jump (CMJ), and drop-jump (DJ) were performed to evaluate the effect of the intervention on strength and power capacities as primary outcomes. Changes in participants’ anthropometric measures, muscle mass, left and right thigh girth, IMTP relative to bodyweight (IMTP-R), eccentric utilization ratio (EUR), and reactive strength index (RSI) were assessed as secondary outcomes. There was no significant interaction (p > 0.05) between group x time in any power and strength outcome, although SJ and EUR showed a trend to significant interaction (p=0.06 and p = 0.065, respectively). There was an overall effect of time (p < 0.05) in all power and strength variables (CMJ, SJ, EUR, DJ, RSI, IMTP, and IMTP-R). There was a significant interaction in muscle mass (MM) [β = 0.57 kg, 95% CI = (0.15; 0.98), t13 = 2.67, p = 0.019], revealing that participants in LL-BFRE increased their muscle mass (6.6 ± 3.1%) compared to HL-RE (3.6 ± 2.0%). Anthropometric variables did not present any group or interaction effect. However, there was a time effect (p < 0.05). Implementing LL-BFRE in place of HL-RE as a conditioning activity in a contrast training sequence might be equally effective in improving lower-body strength and power in preadolescent trampoline gymnasts

Prevention of post-surgical abdominal adhesions by a novel biodegradable thermosensitive PECE hydrogel.

<p>Abstract</p> <p>Background</p> <p>Post-operative peritoneal adhesions are common and serious complications for modern medicine. We aim to prevent post-surgical adhesions using biodegradable and thermosensitive poly(ethylene glycol)-poly(ε-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG, PECE) hydrogel. In this work, we investigated the effect of PECE hydrogel on preventing post-surgical abdominal adhesions in mouse and rat models.</p> <p>Results</p> <p>The PECE hydrogel in sol state could be transformed into gel in less than 20 s at 37°C. In addition, the PECE hydrogel could be easily adhered to the damaged peritoneal surfaces, and be gradually degraded and absorbed by the body within 14 days along with the healing of peritoneal wounds. A notable efficacy of the PECE hydrogel in preventing peritoneal adhesions was demonstrated in the animal models. In contrast, all untreated animals developed adhesions requiring sharp dissection. Furthermore, no significant histopathological changes were observed in main organs of the hydrogel-treated animals.</p> <p>Conclusion</p> <p>Our results suggested that the thermosensitive PECE hydrogel was an effective, safe, and convenient agent on preventing post-surgical intro-abdominal adhesions.</p

Exploring the interaction between renewables and energy storage for zero-carbon electricity systems

Many countries have set ambitious targets to achieve zero-carbon electricity systems by the Mid-21st Century. In their pathways, the renewable mix and the energy storage mix have been considered as two important facets. Current literature mostly focuses on how the storage mix is affected by the renewable mix, but few studied the inverse impact and the dynamic interaction between the storage and renewable mixes. We, therefore, developed an electricity system optimisation model with hourly resolution to investigate how the interaction between renewable and storage mixes could accelerate the decarbonisation in future 30 years. This study considered the decarbonisation roadmap in the UK designed by the National Grid with variable factors such as cost structure of renewables and storages, annual investment budget, and load growth. Our research finds that short-duration energy storages with duration time at 6–8 h are preferred for providing cheap and rapid ramping power to meet the daily fluctuation in the early stage (2020–2030) of the decarbonisation process. In the late stage of retiring fossil fuels (2040–2050), high-share wind energy plus with long-duration storages (with duration time longer than 38 h) can solve the problem of great-quantity and long-lasting energy shortage caused by renewables, thereby achieving high-renewable penetration.</p

BlyS is up-regulated by hypoxia and promotes migration of human breast cancer cells

<p>Abstract</p> <p>Background</p> <p>The role of B Lymphocyte Stimulator (BLyS) in the survival of malignant B cells and the maintenance of normal B cell development and homeostasis has been intensively studied in the literature. However, the influence of BLyS on breast cancer progression remains unclear. The study aimed to investigate the effect of hypoxia on BLyS regulation, cell migratory response to BLyS and the possible molecular mechanisms.</p> <p>Methods</p> <p>In this study, we examined the role of BLyS in the migration of human breast cancer cells by transwell assay. We also explored whether BLyS and its receptors expressed in human breast cancer cell lines by immunofluorescence and Western Blotting. Then we detected the expression level of BLyS in both normoxic and hypoxic conditions by real time-PCR and Western Blotting. Pathways involved were confirmed by Western Blotting, immunofluorescence, transwell assay and luciferase assay.</p> <p>Results</p> <p>According to our study, the expression level of BlyS was increased in human breast cancer cell lines in hypoxic conditions. Up-regulation of this protein led to activation and nuclear translocation of NF-kappa B p65. We also found that the number of migrated cells was increased in the presence of BLyS and inhibition of phosphorylation of Akt attenuated the enhanced migratory response.</p> <p>Conclusions</p> <p>It suggested that better understanding of BLyS, an immunopotentiator, may offer a potential therapeutic target for the treatment of human breast cancers. In addition, BLyS promoted breast cancer cells migration, underscoring the necessity of appropriate applications of immunopotentiators to cancer treatment.</p

LncRNAs: the bridge linking RNA and colorectal cancer.

Long noncoding RNAs (lncRNAs) are transcribed by genomic regions (exceeding 200 nucleotides in length) that do not encode proteins. While the exquisite regulation of lncRNA transcription can provide signals of malignant transformation, lncRNAs control pleiotropic cancer phenotypes through interactions with other cellular molecules including DNA, protein, and RNA. Recent studies have demonstrated that dysregulation of lncRNAs is influential in proliferation, angiogenesis, metastasis, invasion, apoptosis, stemness, and genome instability in colorectal cancer (CRC), with consequent clinical implications. In this review, we explicate the roles of different lncRNAs in CRC, and the potential implications for their clinical application

Epigenetic repression of PDZ-LIM domain-containing protein 2 promotes ovarian cancer via NOS2-derived nitric oxide signaling.

Ovarian cancer constitutes one of the most lethal gynaecological malignancies worldwide and currently no satisfactory therapeutic approaches have been established. Therefore, elucidation of molecular mechanisms to develop targeted therapy of ovarian cancer is crucial. PDLIM2 is critical to promote ubiquitination of nuclear p65 and thus its role in inflammation has been highlighted recently. We demonstrate that PDLIM2 is decreased in both ovarian high-grade serous carcinoma and in various human ovarian cancer cell lines compared with normal ovary tissues and human ovarian surface epithelial cells (HOSE). Further functional analysis revealed that PDLIM2 is epigenetically repressed in ovarian cancer development and inhibition of PDLIM2 promoted ovarian cancer growth both in vivo and in vitro via NOS2-derived nitric oxide signaling, leading to recruitment of M2 type macrophages. These results suggest that PDLIM2 might be involved in ovarian cancer pathogenesis, which could serve as a promising therapeutic target for ovarian cancer patients