Gonad traits and age structure of the sea urchin Heliocidaris crassispina in central range:a comparison with rangeextenders

The sea urchin Heliocidaris crassispina has northern expanded in geographic range to Toga Bay,Oga Peninsula in the Sea of Japan due to the global warming.To demonstrate the gonad traits and age structure of H.crassispina in the central range and compare the difference with those in northern extended range,we collected 100 H.crassispina individuals from a barren off Shitsumi,Fukui(central range),in August 2018.Their growth,gonad traits(size,development and color),and sex ratio were investigated and compared with those in Toga Bay,in August 2014(extended range).The successive 2012–2016 year classes of H.crassispina indicated successive juvenile recruitment in the central range,as found in the extended range.The individuals at three years old in central range were obviously larger than those in the extended range,showing large test diameter and body weight,possibly due to the higher temperature in central range than that in northern extended range.In addition,a balanced sex ratio in the central range was found,in contrast to the female-skewed sex ratio found in the extended range.Gonadal development was sex-and site-dependent.The testicular development in the central range was not only delayed in comparison to ovarian development,but also less delayed than those in the extended range,which possibly attribute to the higher water temperature in the central range.A significantly lower male gonad index and L*(lightness)value was recorded in central ranges compared to that in extended range,possibly due to the releasement of sperm of H.crassispina in central ranges.

Magnetic Fields Affect Alcoholic Liver Disease by Liver Cell Oxidative Stress and Proliferation Regulation

It is well known that alcohol consumption leads to substantially increased free radical levels and health risks,which lacks effective treatment besides alcohol abstinence.Here,we compared different static magnetic field(SMF)settings and found that a downward quasi-uniform SMF of~0.1 to 0.2 T could effectively alleviate alcohol-induced liver damage and lipid accumulation and improve hepatic function.SMFs of two different directions can reduce the inflammation,reactive oxygen species levels,and oxidative stress in the liver,while the downward SMF had more obvious effects.Moreover,we found that the upward direction SMF of~0.1 to 0.2 T could inhibit DNA synthesis and regeneration in hepatocytes,which caused detrimental effects on the lifespan of"heavy drinking"mice.In contrast,the downward SMF prolongs survival of"heavy drinking"mice.On one hand,our study shows that~0.1 to 0.2 T moderate quasi-uniform SMFs with a downward direction have great promises to be developed into a physical method to reduce alcohol-induced liver damage;on the other hand,although the internationally recognized upper limit for SMF public exposure is 0.4 T,people should also pay extra attention to SMF strength,direction,and inhomogeneity that could generate harmful effects on specific severe pathological conditions.

Intermittent F-actin Perturbations by Magnetic Fields Inhibit Breast Cancer Metastasis

F-actin(filamentous actin)has been shown to be sensitive to mechanical stimuli and play critical roles in cell attachment,migration,and cancer metastasis,but there are very limited ways to perturb F-actin dynamics with low cell toxicity.Magnetic field is a noninvasive and reversible physical tool that can easily penetrate cells and human bodies.Here,we show that 0.1/0.4-T 4.2-Hz moderate-intensity low-frequency rotating magnetic field-induced electric field could directly decrease F-actin formation in vitro and in vivo,which results in decreased breast cancer cell migration,invasion,and attachment.Moreover,lowfrequency rotating magnetic fields generated significantly different effects on F-actin in breast cancer vs.noncancerous cells,including F-actin number and their recovery after magnetic field retrieval.Using an intermittent treatment modality,low-frequency rotating magnetic fields could significantly reduce mouse breast cancer metastasis,prolong mouse survival by 31.5 to 46.0%(P<0.0001),and improve their overall physical condition.Therefore,our work demonstrates that low-frequency rotating magnetic fields not only can be used as a research tool to perturb F-actin but also can inhibit breast cancer metastasis through F-actin modulation while having minimum effects on normal cells,which reveals their potential to be developed as temporal-controlled,noninvasive,and high-penetration physical treatments for metastatic cancer.

A Static Magnetic Field Improves Iron Metabolism and Prevents High-Fat-Diet/Streptozocin-Induced Diabetes

Type 2 diabetes(T2D)is a metabolic disorder with high prevalence and severe complications that has recently been indicated to be treatable by a combined static magnetic field(SMF)and electric field.We systematically compared four types of SMFs and found that a downward SMF of
100 mT could effectively reduce the development of hyperglycemia,fatty liver,weight gain,and tissue injury in high-fat-diet(HFD)/streptozocin-induced T2D mice,but not the upward SMF.The downward SMF markedly restored the Bacteroidetes population and reversed the iron complex outer membrane receptor gene reduction in the mice gut microbiota,and reduced iron deposition in the pancreas.SMF also reduced the labile iron and reactive oxygen species level in pancreatic Min6 cells in vitro and prevented palmitate-induced Min6 cell number reduction.Therefore,this simple SMF setting could partially prevent HFD-induced T2D development and ameliorate related symptoms,which could provide a low-cost and non-invasive physical method to prevent and/or treat T2D in the future.

＂Each Has Its Moment＂： Nie Gannu and Modern Chinese Poetry

Nie Gannu 聂绀弩 （1903-86）, essayist and poet, had begun his literary career as an avid advocate of the New Culture and New Literature Movement of the early twentieth century; but later in life, he became well-known for his classical-style poetry. This paper examines the paradox of old and new in Nie Gannu＇s writings by juxtaposing classical-style with new-style poetry for a comparative analysis. In contrast to new-style poetry, classical-style poetry with its prosodic requirements and formal conventions has a strong technical aspect. Nie Gannu＇s preference for the regulated verse in the seven-syllable line is a deliberate embrace of this technical aspect of classical-style poetry： On the one hand, the absorption in poetic skills and craftsmanship was therapeutic for him in the traumatic years of the socialist revolution; on the other, the restraint of the form and the use of parallel couplet afforded him linguistic resources unavailable in the new-style poetry, so that he was able to express emotional complexity, ambivalence, and an irony that is, in his own words, ＂both there and not quite there.＂ Nie Gannu＇s case demonstrates the importance of understanding the new and old verse forms in each other＇s context. Rather than considering the mapping of modern Chinese poetry as following a linear line of progression from classical-style to new-style, this paper proposes a spatial model of configuring the relationship of the two major verse forms in modern times, as mutually defining and constricting.