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关键词： shrimp   nursery diets   black soldier fly   fish meal   replacement  

摘要： The black soldier larvae meal (BSFLM) has been the most extensively studied insect protein source in shrimp nutrition. However, both the availability and prices of BSFLM are still a constraint for its widespread use as an ingredient in animal feeds. The present study investigated the growth and economic performance of post-larval (PL) P. vannamei fed nursery diets with a progressive replacement of fish meal (FML) for BSFLM at 0, 25, 50, 75, and 100%. These replacements corresponded to a dietary inclusion (% of the diet, as-is) of FML and BSFLM of 16.50 and 6.33%, 11.00 and 13.04%, 5.50 and 19.74%, and 0 and 26.46%, respectively. A total of 102,647 shrimp at the age of PL15 with 2.7 +/- 0.2 mg body weight (BW) were stocked in fifty 1.5 m(3) tanks under 1369 PLs/m(3) (2053 +/- 33 PLs/tank) and reared for 42 days. Final shrimp survival (90.5 +/- 7.6%), daily weight gain (14.7 +/- 1.1 mg/day), and apparent feed intake (0.67 +/- 0.03 g of feed per stocked shrimp) were unaffected by dietary treatment. The highest gained yield (791 +/- 52 and 776 +/- 38 g/m(3)) and final BW (621 +/- 7.2 and 632 +/- 7.2 mg) were attained when FML was replaced for BSFLM at 50 and 75% with the lowest at 0% (726 +/- 34 g/m(3) and 598 +/- 8.1 mg, respectively). Shrimp fed diets with 0 and 100% replacement of FML exhibited the highest feed conversion ratio (1.25 +/- 0.04 and 1.24 +/- 0.08) compared to those fed a diet with 50% (1.16 +/- 0.06). At a price of USD 2.00/kg, BSFLM demonstrated a favorable ROI (return of investment) when compared to FML, irrespective of the replacement level. With 25 and 50% replacement, BSFLM remained cost-competitive up to 3.50 USD/kg. At 75% FML replacement, there were no significant differences in ROI with a price range of 2.00 up to 3.04 USD/kg. At full replacement, ROI dropped significantly at a BSFLM price of 2.50 USD/kg and beyond. It can be concluded that FML can be fully replaced for BSFLM in well-balanced nursery diets for P. vannamei. Although the full rep

关键词： Philosophy of computer science   Foundations of computing   Implementation   Software correctness   Miscomputation   Unconventional computing  

摘要： This paper introduces the Global Philosophy symposium on Giuseppe Primiero's book On the Foundations of Computing (2020). The collection gathers commentaries and responses of the author with the aim of engaging with some open questions in the philosophy of computer science. Firstly, this paper introduces the central themes addressed in Primiero's book;secondly, it highlights some of the main critiques from commentators in order to, finally, pinpoint some conceptual challenges indicating future directions for the philosophy of computer science.

关键词： crappie   incubation temperature   ovarian cell isolation   primary cell culture   TrypLE (TM) express  

摘要： Investigations were conducted to develop a general protocol for the isolation and in vitro culture of ovary-derived cells from black crappie, Pomoxis nigromaculatus, and white crappie, P. annularis. Five digestive enzymes: 500 U/mL collagenase type I, 500 U/mL collagenase type IV, 0.05% trypsin-EDTA, 0.25% trypsin-EDTA, and 1X TrypLE (TM) Express were evaluated for live cell isolation. The isolated cells were cultured in 10 or 20% fetal bovine serum (FBS) in L-15 growth media. In addition, four incubation temperatures (15 degrees C, 20 degrees C, 25 degrees C, and 30 degrees C) were also evaluated. The number of live cells obtained from the 0.25% trypsin and TrypLE (TM) Express treatments was significantly higher than other treatments. No difference in cell growth was observed between the two FBS treatments. Cells isolated using TrypLE (TM) Express and 0.25% trypsin reached 80% to 90% confluency in 12.5 cm(2) cell culture flasks within 5 days of inoculation at 20 and 25 degrees C. At 15 degrees C, 10 days were required to reach 80%-90% confluency. Morphologically, cells incubated at 15 degrees C, 20 degrees C, and 25 degrees C appeared healthier than cells incubated at 30 degrees C, where irregular cell shape and substrate detachment were observed. We concluded TrypLE (TM) Express and 0.25% trypsin were optimal for cell dissociation and isolation of crappie ovarian cells. An incubation temperature of 20 degrees C-25 degrees C was favorable for cell culture in L-15 media supplemented with either 10% or 20% FBS.

关键词： Law   Computer science   Policy   Technology  

摘要： A debacle at the company that built ChatGPT highlights concern that commercial forces are acting against the responsible development of artificial-intelligence systems.

关键词： Chemistry   Computer science   Machine learning   Materials science  

摘要： Tool from Google DeepMind predicts nearly 400,000 stable substances, and an autonomous system learns to make them in the lab.

关键词： Students  

摘要： It is imperative for the Computer Science (CS) community to ensure active participation and success of students from diverse backgrounds. This work compares CS to other areas of study with respect to success of students from three underrepresented groups: Women, Black and Hispanic or Latino. Using a data-driven approach, we show that trends of success over the years for underrepresented groups in CS are lagging behind other disciplines. Completion of CS programs by Black students in particular shows an alarming regression in the years 2011 through 2019. This national level decline is most concentrated in the Southeast of the United States and seems to be driven mostly by a small number of institutes that produce a large number of graduates. We strongly believe that more data-driven studies in this area are necessary to make progress towards a more equitable and inclusive CS community. Without an understanding of underlying dynamics, policy makers and practitioners will be unable to make informed decisions about how and where to allocate resources to address the problem. © 2023, CC BY.

关键词： Electrical and electronic engineering   Computer science  

摘要： Recent technological advances have contributed to the rapid increase in algorithmic complexity of applications, ranging from signal processing to autonomous systems. To control this complexity and endow heterogeneous computing systems with autonomous programming and optimization capabilities, we propose a unified, end-to-end, programmable graph representation learning (PGL) framework that mines the complexity of high-level programs down to low-level virtual machine intermediate representation, extracts specific computational patterns, and predicts which code segments run best on a core in heterogeneous hardware. PGL extracts multifractal features from code graphs and exploits graph representation learning strategies for automatic parallelization and correct assignment to heterogeneous processors. The comprehensive evaluation of PGL on existing and emerging complex software demonstrates a 6.42x and 2.02x speedup compared to thread-based execution and state-of-the-art techniques, respectively. Our PGL framework leads to higher processing efficiency, which is crucial for future AI and high-performance computing applications such as autonomous vehicles and machine vision.