In contrast to conventional silk fibroin, spider silk's potential as a scaffold material for tissue engineering is examined in this work. The remarkable qualities of spider silk are being researched for use in making films for tissue regeneration. In comparison to silk fibroin films, the study's analysis of orb-web spider Trichonephila clavata films highlights their improved cell adhesion and nanofibrous network structure. Tests for solubility substantiate the durability of spider silk films, while in vitro investigations demonstrate low cytotoxicity and enhance cellular viability. The conclusion highlights the exceptional properties of spider silk, which make it a viable option for tissue engineering applications and a step forward for in vitro cell culture and regenerative bioengineering.

Silk fibroin (SF) from silkworms has special qualities, and these qualities have drawn a lot of interest lately in SF-based hydrogels for a range of biological applications. However, because there is a dearth of naïve silk materials to collect and prepare, research on the SF-based hydrogels isolated from spider silks has been rather limited. Thus, this study compared the microstructural properties of silk fibroin (SF) hydrogel scaffold, which was taken from the cocoon of the insect silkworm Bombyx mori, with those of hydrogel scaffolds derived from two types of woven silk glands in the orb-web spider Trichonephila clavata: the major ampullate gland (MAG) and the tubuliform gland (TG). The SF hydrogel, which is stabilized by connected SF fibers, has a loose top structure, high porosity, and translucency, according to our FESEM investigation. While the TG hydrogel showed greater porosity, ridge-like or wall-like structures, and stable biocapacity generated by physical cross-linking, the MAG hydrogel showed even higher porosity, elongated fibrous structures, and superior mechanical properties. It is anticipated that the unique microstructural properties of MAG and TG hydrogels will be advantageous when choosing customized substrates to support particular cell types for tissue engineering and regenerative medicine applications.

Transmission electron microscopy was used to examine the microscopic structural features and myofibril organization of cardiac muscle cells in the orb-web spider T. clavata. There are many myofibrils, many mitochondria, a large sarcoplasmic reticulum, and transverse tubules (T-tubules) in the muscle fibers, even if the myofibril striations may not be as noticeable as in skeletal muscles. Because of their consistent striations, sarcomeres are characterized by Z-lines that are 2.0 μm on average in length and do not clearly distinguish between the A- and I-bands. A single T-tubule paired with a terminal cisterna of the sarcoplasmic reticulum constitutes a dyadic junction, which is primarily located at the A-I level of sarcomeres. Cells are joined by intercalated discs, which create several linkages via specialized junctions such as desmosomes, gap junctions, and fascia adherens—all of which are essential for heart function. Our results with transmission electron microscopy (TEM) clearly show that the contraction of the spider's heart muscle is neurogenically controlled, since each fiber is innervated by a motor neuron branch via neuromuscular junctions. These results highlight the neurogenic process controlling spiders' cardiac muscle contractions and advance our knowledge of the peculiar cardiac muscle structure of these animals.

Corn silage is extensively utilized in ruminant feeding on a global scale, with substantial research efforts directed towards enhancing its nutritional worth and managing moisture content. The purpose of this study was to assess the impact of normal cutting height and elevated cutting height on whole-crop corn silage. Corn was harvested at heights of 15 cm and 45 cm above the ground, respectively, 45 days after heading. The harvested corn was cut into 2-3 cm lengths and packed into 20-liter plastic silos in triplicate. The results showed that dry matter (DM), crude protein (CP), water soluble carbohydrates (WSC), and in vitro dry matter digestibility (IVDMD) of C45 were significantly higher than those of the control, while the neutral detergent fiber (NDF) was significantly lower in C45 (p<0.05). The C15 had higher yields than C45 (p<0.05). There was no significant difference in the total digestible nutrients (TDN) yield of whole-crop corn silage. The increase in cutting height resulted in a larger change in moisture content and NDF per centimeter. After 60 days-ensiling, C45 showed significantly lower NH3-N concentrations. Moreover, C45 had significantly higher lactic acid concentration, lactic acid/acetic acid ratio, and lactic acid bacteria count compared to the control. Mold was not detected and the yeast count was less than 2 log10 cfu/g fresh matter in both control and C45. In summary, C45 improved the feeding value and fermentation quality of whole-crop corn silage at the expense of forage productivity.

Interspecies somatic cell nuclear transfer (iSCNT) is a valuable tool for studying the interactions between an oocyte and somatic nucleus. The object of this study was to investigate the developmental competence of in vitro‐matured porcine oocytes after transfer of the somatic cell nuclei of 2 different species (goat and rabbit). Porcine cumulus oocytes were obtained from the follicles of ovaries and matured in TCM‐199. The reconstructed embryos were electrically fused with 2 DC pulses of 1.1 kV/cm for 30 μs in 0.3 M mannitol medium. The activated cloned embryos were cultured in porcine zygote medium‐3 (PZM‐3), mSOF or RDH medium for 7 days. The blastocyst formation rate of the embryos reconstructed from goat or rabbit fetal fibroblasts was significantly lower than that of the embryos reconstructed from porcine fetal fibroblast cells. However, a significantly higher number of embryos reconstructed from goat or rabbit fetal fibroblasts cultured in mSOF or RDH, respectively, developed to the morular stage than those cultured in PZM‐3. These results suggest that goat and bovine fetal fibroblasts were less efficacious than porcine‐porcine cloned embryos and that culture condition could be an important factor in iSCNT. The lower developmental potential of goat‐porcine and porcine‐bovine cloned embryos may be due to incompatibility between the porcine oocyte cytoplasm and goat and bovine somatic nuclei.

Insulin, transferrin and selenium (ITS) complex is reported to improve in vitro development of oocytes and embryos. This study was carried out to investigate the effects of ITS during in vitro culture (IVC) of porcine parthenogenetic and nuclear transfer (NT) embryos on subsequent developmental capacity in vitro. The electrically activated oocytes were cultured in Porcine Zygote Medium (PZM-3) with various concentrations (0, 0.1, 0.5, and 1.0%) of ITS for 7 days. Also, the electrically activated reconstructed embryos were cultured in PZM-3 with various concentrations (0, 0.1, 0.5, and 1.0%) of ITS for 6 days. Addition of ITS to culture medium did not affect development of porcine parthenogenetic embryos in vitro. To test the effect of ITS on the in vitro development of porcine NT embryos, factorial experiments were also performed for in vitro maturation (IVM) medium (TCM-199) with or without 1% ITS and culture medium (PZM-3) with or without 0.5% ITS. Addition of 0.5% ITS to culture medium increased (p<0.05) the proportion of NT blastocysts compared with non-treated group. In contrast, addition of 1% ITS to culture medium was ineffective or had a detrimental effect. Also, addition of ITS only to maturation medium increased (p<0.05) the percentage of NT blastocysts formation compared with the control group. In conclusion, addition of ITS to IVM or IVC medium could improve subsequent blastocyst development of porcine NT embryos.

In the paper, the development of college English teaching and testing in China in the past two decades will be reviewed focusing on the promulgation and implementation of the National College English Teaching Syllabuses since the 1980s and the launch of the National College English Test (CET) in the late 1980s. The second part of the paper focuses on the achievements made and problems encountered in the development of college English teaching and testing. The English proficiency of college students in China will be presented by referring to the CET Syllabus. Examples of students’ performance in the CET will be given to illustrate their communicative competence. The imbalanced development of the English proficiency of college students across the country will also be discussed and possible explanations given for the discrepancy. The paper will then move on to a discussion on the impact of language testing on teaching with special reference to the washback of the CET on college English teaching in China. Both beneficial and detrimental effects of the CET on teaching and learning will be presented and the social consequences of the large-scale standardized test will be discussed in some detail. The paper ends with a brief introduction to the recent reform of the college English teaching and testing in China.

In recent years, the relations between the United States (US) and the countries of the Korean Peninsula began to play a more important role for China. With the improvement of the level of Chinese scholarship, as well as the rapid declassification of the archival material on pre-1980 Cold War history, there emerged a lot of academic publications in China on the 1970s history of US relations with the two Koreas. Although Chinese scholars took different perspectives on this subject, the mainstream view maintains that with the ease of the Cold War tensions in the Northeast Asia, the relations between the United States and the countries on the Peninsula changed in the varying degrees in the 1970s: on the one hand, although the United States and South Korea still maintained their alliance, their relationship was characterized by friction and contradictions, as the issue of the withdrawal of the US troops and the human rights debates had vividly demonstrated; on the other hand, US-North Korean relations were marked by the rapid process of bilateral relaxation. In general, Chinese academic literature on US-South Korean relations is much more profound compared to the scholarly work on American relations with North Korea. And while in recent years remarkable progress has been made by Chinese scholars, there is still plenty of room for improvement, especially in terms of broadening interdisciplinary studies and theory, utilizing multi-archival material, conducting in-depth research of the political systems, the decision-making processes in the relevant countries, as well as the politics within the lower levels of government, etc.