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Large volumes of slags are formed as by-products during the refinement of pig iron by basic oxygen steelmaking or electric arc furnace steelmaking. In order to lower the environmental ...impact of the steel industry and ensure its economic sustainability, there have been significant studies finding the ways to recycle by-products. The formation, composition and physical properties of steel making slag are discussed with regard to the problems associated with its reuse. The volume instability caused by free lime exposure to moisture means that the reuse of steelmaking slag is often limited as many potential applications, and the leaching behavior of steelmaking slag is important for environmental considerations. Land-based applications that have been demonstrated include replacing natural sand as aggregate in cement, which may be combined with the CO2 sequestration properties. Steel slag shows use as a liming material (when spread over acidic soils to help to raise the pH to a more neutral level) and to enhance the physical properties of soft soils. Potential benefits to the marine environment is due to high porosity and large surface area, making slags ideal for coral reef repair (e.g., overcoming coral bleaching) and replacement (e.g., artificial reef to promote growth of green marine plants and seagrass), as well as a growth promoter for seaweed and phytoplankton that are microscopic organisms that are an essential component of ecosystems in oceans around the world. The chemistry of steelmaking slag also makes it a contender for adsorption of H2S and metalloids from marine environments.
This paper reviews the factors affecting the fatty acid composition of adipose tissue and muscle in pigs, sheep and cattle and shows that a major factor is the total amount of fat. The effects of ...fatty acid composition on meat quality are also reviewed. Pigs have high levels of polyunsaturated fatty acids (PUFA), including the long chain (C20-22) PUFA in adipose tissue and muscle. The full range of PUFA are also found in sheep adipose tissue and muscle whereas cattle ‘conserve’ long chain PUFA in muscle phospholipid. Linoleic acid (18:2
n
−
6) is a major ingredient of feeds for all species. Its incorporation into adipose tissue and muscle in relation to the amount in the diet is greater than for other fatty acids. It is deposited in muscle phospholipid at a high level where it and its long chain products eg aracidonic acid (20:4
n
−
6) compete well for insertion into phospholipid molecules. Its proportion in pig adipose tissue declines as fat deposition proceeds and is an index of fatness. The same inverse relationships are not seen in ruminant adipose tissue but in all species the proportion of 18:2
n
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6 declines in muscle as fat deposition increases. The main reason is that phospholipid, where 18:2
n
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6 is located, declines as a proportion of muscle lipid and the proportion of neutral lipid, with its higher content of saturated and monounsaturated fatty acids, increases. Oleic acid (18:1
cis
−
9), formed from stearic acid (18:0) by the enzyme stearoyl Co-A desaturase, is a major component of neutral lipid and in ruminants the same enzyme forms conjugated linoleic acid (CLA), an important nutrient in human nutrition. Like 18:2
n
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6,
α-linolenic acid (18:3
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3) is an essential fatty acid and is important to ruminants since it is the major fatty acid in grass. However it does not compete well for insertion into phospholipid compared with 18:2
n
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6 and its incorporation into adipose tissue and muscle is less efficient. Greater biohydrogenation of 18:3
n
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3 and a long rumen transit time for forage diets also limits the amount available for tissue uptake compared with 18:2
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6 from concentrate diets. A positive feature of grass feeding is that levels of the nutritionally important long chain
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3 PUFA are increased ie EPA (20:5
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3) and DHA (22:6
n
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3). Future research should focus on increasing
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3 PUFA proportions in lean carcasses and the use of biodiverse pastures and conservation processes which retain the benefits of fresh leafy grass offer opportunities to achieve this. The varying fatty acid compositions of adipose tissue and muscle have profound effects on meat quality. Fatty acid composition determines the firmness/oiliness of adipose tissue and the oxidative stability of muscle, which in turn affects flavour and muscle colour. Vitamin E is an essential nutrient, which stabilises PUFA and has a central role in meat quality, particularly in ruminants.
Effects of fatty acids on meat quality: a review Wood, J.D; Richardson, R.I; Nute, G.R ...
Meat science,
2004, 2004-Jan, 2004-1-00, 20040101, Letnik:
66, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
Interest in meat fatty acid composition stems mainly from the need to find ways to produce healthier meat, i.e. with a higher ratio of polyunsaturated (PUFA) to saturated fatty acids and a more ...favourable balance between n-6 and n-3 PUFA. In pigs, the drive has been to increase n-3 PUFA in meat and this can be achieved by feeding sources such as linseed in the diet. Only when concentrations of α-linolenic acid (18:3) approach 3% of neutral lipids or phospholipids are there any adverse effects on meat quality, defined in terms of shelf life (lipid and myoglobin oxidation) and flavour. Ruminant meats are a relatively good source of n-3 PUFA due to the presence of 18:3 in grass. Further increases can be achieved with animals fed grain-based diets by including whole linseed or linseed oil, especially if this is “protected” from rumen biohydrogenation. Long-chain (C20–C22) n-3 PUFA are synthesised from 18:3 in the animal although docosahexaenoic acid (DHA, 22:6) is not increased when diets are supplemented with 18:3. DHA can be increased by feeding sources such as fish oil although too-high levels cause adverse flavour and colour changes. Grass-fed beef and lamb have naturally high levels of 18:3 and long chain n-3 PUFA. These impact on flavour to produce a ‘grass fed’ taste in which other components of grass are also involved. Grazing also provides antioxidants including vitamin E which maintain PUFA levels in meat and prevent quality deterioration during processing and display. In pork, beef and lamb the melting point of lipid and the firmness/hardness of carcass fat is closely related to the concentration of stearic acid (18:0).
The authors present a similarity-based model of induction and categorization in young children (SINC). The model suggests that (a) linguistic labels contribute to the perceived similarity of compared ...entities and (b) categorization and induction are a function of similarity computed over perceptual information and linguistic labels. The model also predicts young children's similarity judgment, induction, and categorization performance under different stimuli and task conditions. Predictions of the model were tested and confirmed in 6 experiments, in which 4- to 5-year-olds performed similarity judgment, induction, and categorization tasks using artificial and real labels (Experiments 1-4) and recognition memory tasks (Experiments 5A and 5B). Results corroborate the similarity-based account of young children's induction and categorization, and they support both qualitative and quantitative predictions of the model.
Hydrogels are broadly used in applications where polymer materials must interface with biology. The hydrogel network is amorphous, with substantial heterogeneity on length scales up to hundreds of ...nanometers, in some cases raising challenges for applications that would benefit from highly structured interactions with biomolecules. Here, we show that it is possible to generate ordered patterns of functional groups on polyacrylamide hydrogel surfaces. We demonstrate that, when linear patterns of amines are transferred to polyacrylamide, they pattern interactions with DNA at the interface, a capability of potential importance for preconcentration in chromatographic applications, as well as for the development of nanostructured hybrid materials and supports for cell culture.
The global pandemic response to COVID-19 has led to the generation of huge volumes of unrecyclable plastic waste from single use disposable face coverings. Rotary hearth furnaces can be used to ...recover Zn and Fe from non-recyclable steelmaking by-product dusts, and waste plastic material such as facemasks could be utilized as a supplementary reductant for the rotary hearth furnace (RHF), but their fibrous form makes milling and processing to appropriate sizing for RHF application extremely challenging. A scalable method of grinding facemasks to powder by melting and mixing with Welsh coal dust reported herein provides a solution to both environmental challenges. The melt-blended PPE/coal dust shows a dramatically improved CO
gasification reactivity (E
= 133-159 kJmol
) when compared to the untreated coal (E
= 183-246 kJmol
), because of improved pore development in the coal during the pyrolysis stage of heating and the catalytic activity of the CaO based ash present in the facemask plastic. The results are promising for the application of waste facemasks in recycling steelmaking by-product dusts in rotary hearth furnaces and may also be suitable for direct injection to the blast furnace subject to further study.
Remote data collection procedures can strengthen developmental science by addressing current limitations to in-person data collection and helping recruit more diverse and larger samples of ...participants. Thus, remote data collection opens an opportunity for more equitable and more replicable developmental science. However, it remains an open question whether remote data collection procedures with children participants produce results comparable to those obtained using in-person data collection. This knowledge is critical to integrate results across studies using different data collection procedures. We developed novel web-based versions of two tasks that have been used in prior work with 4-6-year-old children and recruited children who were participating in a virtual enrichment program. We report the first successful remote replication of two key experimental effects that speak to the emergence of structured semantic representations (
N
= 52) and their role in inferential reasoning (
N
= 40). We discuss the implications of these findings for using remote data collection with children participants, for maintaining research collaborations with community settings, and for strengthening methodological practices in developmental science.
Background
While pancreatic ductal adenocarcinoma is the most common form of pancreatic cancer, many other histologic forms of pancreatic cancer are also recognized. These histologic variants portray ...unique characteristics in terms of patient demographics, tumor behavior, survival, and responsiveness to treatments.
Materials and Methods
Patients who underwent surgical resection of the pancreas for non-metastatic, invasive pancreatic cancer between 2004 and 2014 were selected from the National Cancer Data Base and categorized by histologic variant according to WHO classification guidelines. Patient demographics, tumor variables, treatment characteristics, and survival were compared between histologic groups and subgroups.
Results
A total of 57,804 patients met inclusion and exclusion criteria and were grouped into eight major histologic categories. Survival analysis by the histologic group showed median overall survival of 20.2 months for ductal adenocarcinoma, 20.5 months for squamous cell carcinoma, 26.8 months for mixed acinar-neuroendocrine carcinomas, 52.6 months for cystic mucinous neoplasms with an associated invasive carcinoma, 67.5 months for acinar cell carcinoma, and 69.3 months for mesenchymal tumors. Median survival was not reached for neuroendocrine tumors and solid-pseudopapillary neoplasms, with 5-year overall survival rates of 84% and 97% respectively.
Conclusions
Rare subtypes of pancreatic cancer present unique clinicopathologic characteristics and display distinct tumor biologies. This study presents data on demographic, prognostic, treatment, and survival outcomes between rare forms of pancreatic neoplasms in order to aid understanding of the natural history and behavior of these neoplasms, with the hope of serving as a reference in clinical decision-making and ability to provide accurate prognostic information to patients.
This paper presents the results of the development of a mathematical model and numerical simulation of the ascent in the atmosphere of a vertically directed jet fed by the heat of condensation of ...water vapor on a hygroscopic aerosol introduced into the jet at the start. The possibility of creating artificial convective clouds depending on jet parameters, condensation heat value and vertical profiles of wind speed, air temperature and humidity has been evaluated. Numerical experiments showed that the motion of a high-speed and high-temperature jet in the atmosphere has a complex turbulent nature. As the jet ascends, it expands, losing superheat and velocity. The temperature of the jet decreases faster than the velocity, so the jet rises slightly above the level at which its superheat disappears. The jet's ascent height increases as the humidity of the air and the vertical temperature gradient increase. Wind causes the jet to deform, bend, and decrease the height of ascent. Feed the jet with condensation heat results in a significant increase in jet lift height. This is particularly effective in the case of introducing into the jet two-layer NaCl/TiO
nanoaerosol, which is capable of absorbing water vapor in an amount significantly greater than its mass. The simulation results are encouraging in the possibility of creating artificial updrafts that can lead to the formation of convective clouds and precipitation on days with favorable atmospheric conditions, when wind speed in the sub-cloud layer is < 6 m/s, air humidity is > 65%, and the temperature lapse rate is > 7.5 °C/km.
A key developmental transition in executive function is in the temporal dynamics of its engagement: children shift from reactively calling to mind task-relevant information as needed, to being able ...to proactively maintain information across time in anticipation of upcoming demands. This transition is important for understanding individual differences and developmental changes in executive function; however, methods targeting its assessment are limited. We tested the possibility that Track-It, a paradigm developed to measure selective sustained attention, also indexes proactive control. In this task children must track a target shape as it moves unpredictably among moving distractors, and identify where it disappears, which may require proactively maintaining information about the target or goal. In two experiments (5-6 year-olds, Ns = 33, 64), children's performance on Track-It predicted proactive control across two established paradigms. These findings suggest Track-It measures proactive control in children. Theoretical possibilities regarding how proactive control and selective sustained attention may be related are also discussed.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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