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To evaluate the relationship between muscle fiber characteristics and the quality of frozen/thawed pork meat, four different muscles, M. longissimus thoracis et lumborum (LTL), M. psoas major (PM), M. semimembranosus (SM), and M. semitendinosus (ST), were analyzed from twenty carcasses. Meat color values (lightness, redness, yellowness, chroma, and hue) changed due to freezing/thawing in LTL, which showed larger IIAX, IIX, and IIXB fibers than found in SM (P P P P

This study aimed to compare the similarities, physicochemical properties, and muscle fiber characteristics of porcine skeletal muscles. Fourteen types of muscles were collected from nine pig carcasses at 24 h post-mortem and classified by muscle architecture into two main groups, namely parallel and pennate. The muscles were further differentiated into three subtypes per group. These included fan-shaped, fusiform, and strap for the parallel group, and unipennate, bipennate, and multipennate for the pennate group. Parallel-fibered muscles, which were composed of larger I, IIA, IIX, and IIXB fibers and a lower density of IIA fibers, showed higher redness and yellowness values than pennate-fibered muscles (p0.05). However, the relative fiber area was not significantly different between the parallel and pennate groups (p0.05). In the subtypes of parallel architecture, the strap group showed lower moisture content and higher redness values than the other subtypes and had considerably higher amounts of oxidative fibers (I and IIA; 72.3%) than the fan-shaped and fusiform groups (p0.05). In the pennate group, unipennate showed comparatively lower moisture content and higher lightness than other pennate subtypes and was composed of smaller I, IIA, and IIX fibers than the bipennate and multipennate groups (p0.05). Finally, a different trend of muscle clustering by hierarchical cluster analysis was found between physicochemical properties and muscle fiber characteristics. These results suggest that the physicochemical properties and muscle fiber characteristics of porcine skeletal muscles are not significantly dependent on morphological properties but are rather related to the intrinsic properties of the individual muscles.

The influence of muscle architecture on muscle fiber characteristics and meat quality has not been fully elucidated. In the present study, muscle fiber characteristics on the chop surface of pork loin (M. longissimus thoracis et lumborum, LTL), pennation angle degree, and meat quality were evaluated to understand the pork LTL architecture and its relationship with the loin chop quality. Muscle fiber pennation degree ranged from 51.33° to 69.00°, resulting in an ellipse-shaped muscle fiber on the surface of pork loin chop. The cross-sectional area (CSA) on the sections cut vertical to the muscle length (M-Vertical) was considerably larger (p0.05). These observations might help us in better understanding pork loin architecture and the relationship between the pennation angle, muscle fiber characteristics, and meat quality of pork loin chop.

Many studies have been conducted to improve economically important livestock traits such as feed efficiency and muscle growth. Genome editing technologies represent a major advancement for both basic research and agronomic biotechnology development. The clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technical platform is a powerful tool used to engineer specific targeted loci. However, the potential occurrence of off-target effects, including the cleavage of unintended targets, limits the practical applications of Cas9-mediated genome editing. In this study, to minimize the off-target effects of this technology, we utilized D10A-Cas9 nickase to generate myostatin-knockout (MSTN KO) chickens via primordial germ cells. D10A-Cas9 nickase (Cas9n)-mediated MSTN KO chickens exhibited significantly larger skeletal muscles in the breast and leg. Degrees of skeletal muscle hypertrophy and hyperplasia induced by myostatin deletion differed by sex and muscle type. The abdominal fat deposition was dramatically lower in MSTN KO chickens than in wild-type chickens. Our results demonstrate that the D10A-Cas9 technical platform can facilitate precise and efficient targeted genome engineering and may broaden the range of applications for genome-edited chickens in practical industrialization and as animal models of human diseases.

The effect of freezing raw meat on the quality characteristics of beef jerky was evaluated in the present study. Jerky was made using different types of raw beef (fresh, frozen, and frozen-thawed) with different curing times (6 h and 12 h). Frozen-thawed beef had a lower moisture content than fresh or frozen beef due to higher exudate loss (P 0.05). Jerky made using frozen and frozen-thawed beef showed lower drying yield and higher shear force than jerky prepared using fresh beef (P 0.05). Freezing raw beef decreased the fat content and increased the redness, yellowness, chroma, and hue values of jerky (P 0.05). The microstructure of beef jerky was showed to increase the deformation and contraction of muscle fibers due to freezing. Longer curing times increased the moisture content of jerky made using frozen meat (P 0.05). Jerky made using frozen or frozen-thawed meat was tough due to excessive fat and moisture loss.

The proteolysis trends and meat quality of the chicken pectoralis major (PM) and iliotibialis (IL) muscles stored at 4°C for 7 d were investigated. After 7 d of storage, the purge loss was higher (P0.05) in PM than in IL muscle. The difference in the composition of muscle fibers between PM (100% fast type) and IL (88.85% fast and 11.15% slow types) resulted in differences in proteolysis. Fructose-bisphosphate aldolase, troponin I, myosin heavy chain, and malate dehydrogenase exhibited the same tendencies, but pyruvate kinase, creatine kinase, L-lactate dehydrogenase, and triosephosphate isomerase exhibited different tendencies in the 2 muscles. The activity of cathepsin B was higher in PM than in IL during storage (P0.05). These results indicate that the proteolysis trend and changes in meat quality during cold storage are dependent on the different muscle fiber characteristics.

The microrchidia (MORC)-family CW-type zinc finger 2 (MORC2) gene is related to DNA repair, adipogenesis and epigenetic silencing via the human silencing hub (HUSH) complex. MORC2 missense mutation is known to cause peripheral neuropathy of Charcot-Marie-Tooth disease type 2 Z (CMT2Z). However, there have been reports of peripheral and central neuropathy in patients, and the disease has been co-categorized with developmental delay, impaired growth, dysmorphic facies and axonal neuropathy (DIGFAN). The etiology of MORC2 mutation-mediated neuropathy remains uncertain. Here, we established and analyzed Morc2a p.S87L mutant mice. Morc2a p.S87L mice displayed the clinical symptoms expected in human CMT2Z patients, such as axonal neuropathy and skeletal muscle weakness. Notably, we observed severe central neuropathy with cerebella ataxia, cognition disorder and motor neuron degeneration in the spinal cord, and this seemed to be evidence of DIGFAN. Morc2a p.S87L mice exhibited an accumulation of DNA damage in neuronal cells, followed by p53/cytochrome c/caspase 9/caspase 3-mediated apoptosis. This study presents a new mouse model of CMT2Z and DIGFAN with a Morc2a p.S87L mutation. We suggest that neuronal apoptosis is a possible target for therapeutic approach in MORC2 missense mutation. This article has an associated First Person interview with the first author of the paper., Summary: We present a new mouse model of Charcot-Marie-Tooth disease type 2 Z and developmental delay, impaired growth, dysmorphic facies and axonal neuropathy syndrome with a Morc2a p.S87L mutation, exhibiting peripheral and central neuronal apoptosis.

This study was conducted to evaluate the proteolysis trends and change in meat quality during 10 days of cold storage in duck M.

In this study, the relationship between muscle fiber characteristics and meat quality of pork loin chops prepared using different directions of cut (vertical to the muscle length, M-Vertical, vertical or parallel to the muscle fiber orientation, F-Vertical or F-Parallel) was evaluated under different storage conditions (fresh, cold storage/aged, and freeze&ndash, thawed). Among the three groups, F-parallel displayed considerably larger size of muscle fibers, regardless of their type. This group also displayed an increase in discoloration in aged chops and a decrease in purge loss and tenderness than in other cut groups (p &lt, 0.05). Freeze&ndash, thawing accelerated deterioration of meat quality, especially water-holding capacity and tenderness in all groups (p &lt, 0.05), but was most prominent in F-Parallel. Therefore, to avoid excessive deterioration of fresh, aged, or frozen/thawed pork loin chops, it is important to consider the direction in which the chop is cut with respect to the muscle fiber orientation.

To understand muscular steatosis observed in beef carcasses, physicochemical and histochemical characteristics were compared between abnormal (massive fatty replaced) and normal regions of beef striploin. Fat content in the abnormal region (48.02%) was approximately twice than that in the normal region (22.01%). However, fatty acids did not show significant (P 0.05) differences in their compositions between the two regions. Tenderness was significantly (P 0.05) higher in the abnormal region. However, other meat quality traits were not significantly (P 0.05) different between the two regions. Massive accumulation of adipocytes was accompanied by muscle fiber atrophy regardless of muscle fiber types. Without a change in total muscle fiber density, oxidative fiber composition was significantly increased, whereas glycolytic fiber composition was decreased (P 0.05). These findings suggest that adipogenic transdifferentiation and muscle fiber type switching can occur within the muscle due to muscular steatosis.

The association of muscle fiber characteristics (MFC) with freeze-thawed meat quality was investigated using four different cuts (loin, M. longissimus thoracis; tenderloin, M. psoas major; top round, M. semimembranosus; eye of round, M. semitendinosus) obtained from beef carcasses (n = 10; Hanwoo steer; 28 months of age). Tenderloin had higher (P .05) composition of muscle fiber type I than the others. Its quality traits except cooking loss were not affected by freeze-thawing (P .05). However, top round having lower type I and higher type IIX compositions showed lower water-holding capacity and larger discoloration (P .01) than other beef cuts after freeze-thawing. Increased tenderness after freeze-thawing was observed only for loin (P .01) which had relatively larger size of type I fibers. In conclusion, individual muscle has different susceptibilities to freezing due to their different MFC. Considering different MFC by meat type when freezing meat will help to prevent excessive deterioration of meat quality.

This study analyzes the plugging effect considering drive-ability using field test and numerical analysis, CEL method (Coupled Eulerian and Lagrangian technique). Overall, the results show the reduction trend of end bearing capacity in the large diameter open-ended steel piles due to the plugging effect. To simulate the process of pile driving, this research considered BPM (Blow per Meter) theory. The factors of parametric studies are the pile diameter, the pile length, the soil condition in sand and the driving energy of pile controlled by BPM. Through the results of numerical analysis, this research proposed that a downward trend of plugging effect in the case of increasing pile diameter and a new end bearing equation.

Peptides derived from whole proteins in beef tenderloin (M. psoas major, PM) and striploin (M. longissimus lumborum, LL) associated with meat quality and muscle fiber composition were identified and quantified during 21 days of aging. Peptide quantification revealed 40-43 proteins to be significantly degraded during all aging time, and these were mostly sarcoplasmic proteins. Cooking loss of both muscles was not changed by aging (P 0.05), whereas Warner-Bratzler shear force and meat color were affected by aging. Sensory tenderness increased in PM after 14 days of aging (P 0.05). PM had a higher type I fiber content, whereas LL had a higher type IIX fiber content (P 0.05), resulting in differences in proteolysis during all aging periods tested. These findings improve our understanding of different biochemical and physicochemical changes in aged meat according to the muscle type.

This paper describes experiments comparing a commercially available R410A heat pump and prototype R744 (carbon dioxide) system in heating mode. The R744 system utilizes aluminum microchannel heat exchangers and a prototype semi-hermetic compressor. System performance is compared for two configurations: first, when the R744 compressor speed is set to match the baseline system’s heating capacity at 8.2 °C outdoors and 21.1 °C indoors; and second, when the air conditioning capacity is matched at 35 °C outdoors and 26.5 °C indoors. The R744 system operates with a slightly lower heating COP, but its higher capacity at lower outdoor temperatures reduces the need for less efficient supplementary heating capacity.

The effect of air inlet humidity condition on the air-side heat transfer and pressure drop characteristics for an inclined brazed aluminum heat exchanger has been investigated experimentally. For a heat exchanger with a louver angle of 27°, fin pitch of 2.1 mm and flow depth of 27.9 mm, a series of tests are conducted for the air-side Reynolds numbers of 80–400, with variation of inlet humidity condition. The heat transfer data are obtained for wet condition only and the pressure drop data are measured for both dry and wet conditions. The inlet air temperature and relative humidity range are 12 °C and 60–90%, respectively. The inclination angles ( θ ) from the vertical position are 0, 14, 45, and 67° clockwise (leeward direction). The inclination angles affect moderately the sensible heat transfer coefficient for wet condition, and the pressure drops for both dry and wet conditions increase systematically with the inclination angle. The heat transfer and pressure drop characteristics under wet condition are not influenced substantially by the air inlet humidity for θ ⩽45°. The effect of the louver directions at the inlet and outlet of the inclined heat exchanger on the performance is also addressed.

Ideological and political education is the fine tradition that Chinese Communist Party has stuck to all the time and acts as a key which keeps core status and leadership of Chinese Communist Party in the field of social ideology. Thus, the country has been paying much attention to ideological and political education work. Currently, global situation is increasingly numerous and complicated. Besides, China has insisted on Reform and Opening-up for a long time and persisted in 'bring in' and 'go global' strategies. Undoubtedly, social culture will show a diversified and complicated situation. College students face with challenges of value orientation, so it is obvious that transition of colleges' ideological and political education has become an urgent affair.

In this study, we investigated isotropic/anisotropic selective area growth of the Si and SiGe epitaxial layers at various growth conditions and pattern sizes. Si and SiGe epitaxial layers were selectively grown on LOCOS patterned Si substrates by a cold wall-type ultrahigh vacuum chemical vapor deposition (UHV-CVD) system.

Many applications, such as telecommunication, process control, and virtual reality, require real-time access to database. Main-memory DBMS, which becomes feasible with the increasing availability of large and relatively cheap memory, can provide better performance than disk-based systems for real-time applications. This paper presents an overall architecture of M/sup 2/RT, a main-memory real-time DBMS, and an object-oriented design of its storage system called M/sup 2/RTSS. M/sup 2/RTSS provides classes that implement the core functionality of storage management, real-time transaction scheduling, and recovery. Implemetation-specific information is encapsulated in these classes and extensions can be made by inheritance. With object-oriented features, M/sup 2/RTSS can easily incorporate new development in application requirements and the result of ongoing research in real-time systems.