End Of Production Research Articles

Mapping sustainable options in the fashion industry: A systematic literature review and a future research agenda

AbstractThe fashion industry accounts for large impacts on the environment and social welfare, both on the consumers' and companies' sides. This study systematically reviews the literature on sustainable consumption in the fashion industry, clarifying sustainable fashion's meaning. Existing sustainable fashion solutions are investigated from consumers' behavior perspective and classified into three consumption phases, that is, (pre‐)purchase, use, and post‐use. 187 articles are included, and twenty‐six sustainable solutions are identified across the consumption phases. These include techniques, features, services, and behaviors able to increase garment sustainability by mitigating negative impacts and ensuring product circularity by recycling and/or reusing at the product's end of life, representing promising strategies for fostering a transition toward sustainable fashion consumption practices. An innovative and comprehensive framework of sustainable fashion solutions is developed. Future research agenda and a sustainable offering inventory for marketers are provided.

High-Proportion Blue Light Irradiation at the End-of-Production Stage Promotes the Biosynthesis and Recycling of Ascorbate in Lettuce.

Ascorbate (AsA), an essential antioxidant for both plants and the human body, plays a vital role in maintaining proper functionality. Light plays an important role in metabolism of AsA in horticultural plants. Our previous research has revealed that subjecting lettuce to high light irradiation (HLI) (500 μmol·m-2·s-1) at the end-of-production (EOP) stage effectively enhances AsA levels, while the optimal light quality for AsA accumulation is still unknown. In this study, four combinations of red (R) and blue (B) light spectra with the ratio of 1:1 (1R1B), 2:1 (2R1B), 3:1 (3R1B), and 4:1 (4R1B) were applied to investigate the biosynthesis and recycling of AsA in lettuce. The results demonstrated that the AsA/total-AsA content in lettuce leaves was notably augmented upon exposure to 1R1B and 2R1B. Interestingly, AsA levels across all treatments increased rapidly at the early stage (2-8 h) of irradiation, while they increased slowly at the late stage (8-16 h). The activity of L-galactono-1,4-lactone dehydrogenase was augmented under 1R1B treatment, which is pivotal to AsA production. Additionally, the activities of enzymes key to AsA cycling were enhanced by 1R1B and 2R1B treatments, including ascorbate peroxidase, dehydroascorbate reductase, and monodehydroascorbate reductase. Notably, hydrogen peroxide and malondialdehyde accumulation increased dramatically following 16 h of 1R1B and 2R1B treatments. In addition, although soluble sugar and starch contents were enhanced by EOP-HLI, this effect was comparatively subdued under the 1R1B treatment. Overall, these results indicated that AsA accumulation was improved by irradiation with a blue light proportion of over 50% in lettuce, aligning with the heightened activities of key enzymes responsible for AsA synthesis, as well as the accrual of hydrogen peroxide. The effective strategy holds the potential to enhance the nutritional quality of lettuce while bolstering its antioxidant defenses.

End-of-production Ultraviolet A and Blue Light Similarly Increase Lettuce Coloration and Phytochemical Concentrations

Anthocyanins are a group of human-health-promoting phenolic compounds that influence the pigmentation of red-leaf lettuce (Lactuca sativa). Ultraviolet A (UVA; 315–399 nm) and blue (B; 400–499 nm) light can increase the concentrations of phenolic compounds but also suppress cellular expansion, which can limit harvestable biomass accumulation. It is not known whether UVA or B light is more effective at increasing phenolic compound concentrations when they are each applied at the same photon flux density. Our objective was to evaluate the efficacy of UVA and B light when added during the end of production (EOP) at promoting phenolic compound synthesis and red-leaf coloration without limiting biomass accumulation. We grew red-leaf lettuce ‘Rouxai’ in a controlled indoor environment at an air temperature of 22 °C under warm-white and red light-emitting diodes (LEDs). On day 24, 30 or 60 µmol·m−2·s−1 from UVA, B, UVA plus B, or red plus green LEDs was added during the last 6 days of the 30-day production period. UVA and B light, alone or combined, similarly increased leaf redness (by up to 72%), total phenolic concentration (by up to 92%), total anthocyanin concentration (by up to 2.7-fold), and relative chlorophyll concentration (by up to 20%) and did not inhibit growth, compared with lettuce grown without EOP supplemental lighting. Considering B light was as effective as UVA light at increasing leaf color and phytonutrient density and that B LEDs are more electrically effective, economical, and durable, an enriched blue-light spectrum at the EOP is a comparatively sustainable method to increase crop quality without suppressing biomass accumulation.

Lack of Blue Light Regulation of Antioxidants and Chilling Tolerance in Basil.

Blue light, measuring from 400 to 500 nm, is generally assumed to increase the content of antioxidants in plants independent of the species. Blue light stimulates the biosynthesis of phenolic compounds such as flavonoids and their subclass anthocyanins from the phenylpropanoid pathway. Flavonoids, anthocyanins, and phenolic acids are strong reactive oxygen species (ROS) scavengers and may lessen the symptoms of abiotic stresses such as chilling. We tested the hypothesis that a high percentage of blue light induces the accumulation of antioxidants and that this effect depends on the photosynthetic photon flux density (PPFD, 400–700 nm). The effect may be more pronounced at a lower PPFD. We investigated the changes in primary and secondary metabolites of basil in response to the percentage of blue light (9, 33, 65, and 100%) applied either as a 5-day End-Of-Production (EOP) treatment or continuous throughout the growth cycle in the green cv. Dolly. We also studied if the response to the percentage of blue light (9 or 90%) was dependent on the total PPFD (100 or 300 μmol m–2 s–1 PPFD) when applied as a 5-day EOP treatment in the green cv. Dolly and the purple cv. Rosie. For both green and purple basil, it was found that the percentage of blue light had little effect on the levels of antioxidants (rosmarinic acid, total ascorbic acid, total flavonoids, and total anthocyanins) at harvest and no interactive effect with PPFD was found. Antioxidants generally decreased during postharvest storage, wherein the decrease was more pronounced at 4 than at 12°C. Chilling injury, as judged from a decrease in Fv/Fm values and from the occurrence of black necrotic areas, was not affected by the percentage of blue light. Particularly, chilling tolerance in the purple cultivar was increased in plants grown under higher PPFD. This may be related to the increased levels of soluble sugar and starch in leaves from high PPFD treated plants.

Effect of end-of production continuous lighting on yield and nutritional value of Brassicaceae microgreens

The effect of continuous lighting applied in the end-of-production period on growth and nutritional quality of radish (Raphanus sativus var. radicula), broccoli (Brassica oleracea var. italic), mizuna (Brassica rapa. var. nipposinica) and arugula (Eruca sativa) was investigated in growth chambers under LED lighting. Microgreens were grown under 16 h photoperiod and 3 days before harvest half of plants were placed under continuous lighting conditions. Pre-harvest continuous lighting treatment increased yield, robustness index, and shorten time to harvest in radish, broccoli, mizuna and arugula microgreens. The end-of-production treatment has also led to higher content of compounds with antioxidative properties (flavonoids, proline) and increased the activity of antioxidant enzymes (CAT, APX, GPX) by inducing mild photooxidative stress. Increased antioxidative status added nutritional value to microgreens that can be used as functional foods providing health benefits. Pre-harvest treatment by continuous lighting is suggested as the practice than can allow producers to increase yield, aesthetic appeal, nutritional quality, and market value of Brassicacea microgreens.

Regulation of ascorbate accumulation and metabolism in lettuce by end-of-production high light irradiation provided by red and blue LEDs

Increasing the L-ascorbate (AsA) content of vegetables is very important for improving plant quality in greenhouses and plant factories because AsA is an antioxidant that is essential for the proper function of plants and the human body. End-of-production (EOP) high light irradiation is an economical preharvest practice for improving product quality. Here, we studied the dynamic responses of the AsA pool and AsA metabolism in lettuce exposed to EOP high light irradiation (300, 400, and 500 μmol m−2·s−1) from red and blue LEDs over a 16-h time course. Compared to the control (200 μmol m−2·s−1), the content of AsA and total AsA (T-AsA) in lettuce leaves significantly increased after 8 h of high light irradiation, and the contents of AsA and T-AsA increased by 42.4 % and 36.9 %, respectively, under 500 μmol m−2·s−1 irradiation. Transcript levels of the AsA metabolism-related genes GME, GGP, GPP, GLDH, APX, MDHAR1, MDHAR2, DHAR1, DHAR2, and GR were upregulated under higher light. Likewise, the activities of AsA-related enzymes (GLDH, APX, DHAR, and GR) increased under 500 μmol m−2·s−1. The expression of genes (GGP, GPP, GLDH, MDHAR1, MDHAR2, DHAR1, DHAR2, and GR) was more sensitive to high light irradiation in AsA metabolism. Both high light intensity and long irradiation time increased the soluble sugar content. Moreover, high light intensity (500 μmol m−2·s−1) increased the content of H2O2, O2*−, and MDA in lettuce leaves, especially at 16 h. In conclusion, EOP high light increased AsA levels by upregulating the expression of genes and the activity of enzymes in AsA metabolism. The increase in soluble sugar availability and the signaling of reactive oxygen species also contributed to AsA accumulation. We therefore recommend 8 h of high light (500 μmol m−2·s−1) irradiation before harvest to increase the AsA content of lettuce.

High Light Intensity Applied Shortly Before Harvest Improves Lettuce Nutritional Quality and Extends the Shelf Life.

The effect of light intensity applied shortly before harvest on the nutritional quality, postharvest performance, and shelf life of loose-leaf lettuce (Lactuca sativa L. cv. Expertise RZ Salanova®) was investigated. Lettuce was grown either in a greenhouse with supplemental high-pressure sodium light (Experiment 1, EXP 1) or in a climate room under white LED light (Experiment 2, EXP 2). In both experiments full grown plants were transferred to a climate room for the End of Production (EoP) light treatments during the last week of cultivation. During EoP lighting plants were exposed to different intensities (0, 110, and 270 μmol m–2 s–1 in EXP 1; 50, 210, and 470 μmol m–2 s–1 in EXP 2) from white-red LEDs for 6 (EXP 2) or 7 days (EXP 1). Mature leaves were then harvested and stored in darkness at 10°C to study the postharvest performance. Changes in dry matter content, total ascorbic acid, and carbohydrates (including glucose, fructose sucrose, and starch) levels were determined during EoP lighting and during the subsequent shelf life as indicators of lettuce nutritional quality. Quality aspects (appearance, texture, and odor) were accessed during the shelf life as indicators of postharvest performance. In both experiments, high light intensities applied in EoP lighting increased dry matter percentage and contents of ascorbic acid (AsA) and carbohydrates at harvest and these increased levels were maintained during the shelf life. Increased light intensity in EoP treatment also extended the shelf life. The levels of AsA and carbohydrates at harvest correlated positively with the subsequent shelf life, indicating that the prolonged shelf life relies on the improved energy and antioxidant status of the crop at harvest.

Response of Basil Growth and Morphology to Light Intensity and Spectrum in a Vertical Farm.

Vertical farming is becoming increasingly popular for production of leafy vegetables and herbs, with basil (Ocimum basilicum L.) as one of the most popular herbs. In basil most research has focused on increasing secondary metabolites with light spectra. However, knowledge about the effect of light intensity (photosynthetic photon flux density, PPFD) and spectra on growth and morphology is key for optimizing quality at harvest. The impact of PPFD and spectrum on plant growth and development is species dependent and currently few studies in basil are available. Understanding the response to End-Of-Production (EOP) light of growth and morphology is important for successful vertical farming. We performed a comprehensive series of experiments, where the effects of EOP PPFD, fraction of blue and their interaction on the growth and morphology were analyzed in two green and one purple basil cultivar. In addition, the impact of different EOP intensities and duration of far-red were investigated. We found that increasing the PPFD increased fresh mass, dry matter content and plant height in all three cultivars. The responses were linear or quadratic depending on the cultivar. A high fraction of blue (>90%) increased plant height and decreased the dry mass partitioning to the leaves. The only interaction found between the fraction of blue and overall PPFD was on plant height in the green cultivar whereas other growth parameters and morphology responded stronger to PPFD than to the fraction of blue light. Plant dry matter production was increased with the addition of far-red. Far-red EOP intensity treatments enhanced the fraction of dry mass partitioned to the leaves, whereas a prolonged far-red treatment enhanced partitioning to the stem. Both plant fresh mass and dry matter content were improved by applying high PPFD shortly before harvest. Light spectra were found to be of less importance than PPFD with respect to plant dry matter content. Light use efficiency (LUE) based on fresh mass decreased with increasing PPFD whereas LUE based on dry mass increased with increasing PPFD, when given as EOP treatments. The overall physiological mechanisms of the light intensity and spectral effects are discussed.

Effect of End-of-production High-energy Radiation on Nutritional Quality of Indoor-grown Red-leaf Lettuce

Numerous studies have evaluated the effect of high-energy radiation as means to increase nutritional quality of lettuce (Lactuca sativa). However, most research has focused on providing constant radiation quality or quantity throughout the production cycle, which typically results in yield reductions or increases in production costs. End-of-production (EOP) radiation is a cost-effective, preharvest practice that can allow growers to manipulate product quality and thus increase market value of lettuce without negatively affecting plant growth. The objective of this study was to quantify and compare growth and accumulation of secondary metabolites from ‘Rouxaï RZ’ and ‘Codex RZ’ red-leaf lettuce grown indoors and exposed to different strategies of EOP high-energy radiation. Plants were grown for 24 days under an average daily light integral (DLI) of 15.8 mol·m‒2·d‒1 (220 µmol·m‒2·s‒1 for 20 h·d−1) using red:blue light-emitting diode (LED) lamps. Four days before harvest (36 days after sowing), plants were exposed to one of three EOP treatments added to red:blue LEDs: 1) ultraviolet-A (EOP-ultraviolet); 2) high blue (EOP-B); or 3) high-intensity (EOP-H) radiation. A fourth treatment was included as a control, with no EOP. Except for EOP-H, all treatments provided a DLI of 15.8 mol·m‒2·d‒1; EOP-H provided a DLI of 31.7 mol·m‒2·d‒1. No treatment differences were measured for shoot fresh weight (FW) of ‘Rouxaï RZ’ but shoot FW of ‘Codex RZ’ was negatively affected by EOP radiation, indicating potential changes in lettuce yield from applying EOP high-energy radiation during active plant growth. In general, EOP treatments did not affect total phenolic content and total carotenoid concentration of plants, but anthocyanin content and antioxidant capacity were positively influenced by EOP-B and EOP-H, whereas EOP-ultraviolet resulted in similar nutritional quality to control. Findings from this study indicate that EOP high-energy radiation, especially EOP-B, has significant potential to improve the nutritional quality of red-leaf lettuce grown in controlled environments.

Development of Product Recyclability Index Utilizing Design for Assembly and Disassembly Principles

Designing products for recyclability is driven by environmental and economic goals. Several design for assembly (DFA) rules and parameters can be used to gauge the recyclability index of product designs. These indices can be used for comparative analysis of the recyclability of different products. This assists the designer in making design choices related to the product's end of life. However, many of the existing recyclability indices are only available after design and manufacturing decisions are made. If such design decisions could be made earlier in the design process, when the design space is less bound, recyclability could be considered earlier. A case study is performed to determine if DFA parameters could be utilized to determine product recyclability. The parameters were obtained from existing DFA time estimate tables. The results of the study indicated that the recyclability of the product, as defined by established recyclability metrics, could be predicted through DFA measures. A negative correlation was realized between recyclability and insertion time. Components that required greater time to mate during assembly adversely affected the recyclability of the product. Conversely, handing time was found to have no predictive capability on product recyclability. These findings are used to develop a recyclability index that utilizes the DFA measures, allowing designers and engineers to determine recyclability earlier in the design process.

Planting Date, Maturity, and Temperature Effects on Soybean Seed Yield and Composition

Core Ideas Planting date and maturity group decisions can greatly affect yield and composition. Temperature had a significant effect on seed yield and composition. Planting date × maturity group should be chosen based on the product's end use. Soybean [Glycine max (L.) Merr.] production has greatly increased in the upper U.S. Midwest over the last decade, but little information exists regarding the interactive effects of environment and spring management decisions on soybean seed yield and composition. Our objective was to assess the effect of four planting dates (PDs), four cultivar maturity groups (MGs), and ambient temperature between R5 to R8 (T5–T8) on soybean seed yield and composition. Field studies were established between 2014 and 2016 at three locations in Wisconsin and one in Minnesota. Across environmental conditions and management decisions, greater seed yield was positively correlated with protein and oil contents but negatively correlated with linoleic, linolenic, and sucrose contents. Multivariate data analysis showed positive synergies between early planting (late April–early May) and MG 2 for yield, oil, and oleic acid across the examined region. A MG 2 was the highest yielding and a ∼1200 kg ha−1 yield difference was observed between early and late PDs. These results underline the complexity of the soybean yield‐composition relationships. Additionally, the large variability in the responses of constituents to management decisions and temperature variations highlights the importance of a producer knowing the product's end use (e.g., high yield vs. high protein) and accordingly modifying the growing environment by selecting an appropriate PD and MG for the respective region. To provide more accurate recommendations to a broader range of producers, multi‐environment studies are imperative to capture large environmental variability in important soybean production areas across the United States.

Semi-automatic Design for Disassembly Strategy Planning: An Augmented Reality Approach

The mounting attention to environmental issues requires adopting better disassembly procedures at the product's End of Life. Planning and reckoning different disassembly strategies in the early stage of the design process can improve the development of sustainable products with an easy dismissing and recycling oriented approach. Nowadays many Computer Aided Process Planning software packages provide optimized assembly or disassembly sequences, but they are mainly based on a time and cost compression approach, neglecting the human factor. The environment we developed is based upon the integration of a CAD, an Augmented Reality tool, a Leap Motion Controller device, see-through glasses and an algorithm for disassembly strategies evaluation: this approach guarantees a more effective interaction with the 3D real and virtual assembly than an approach relying only on a CAD based disassembly sequence planning. In such a way, the operator may not test in a more natural and intuitive way automatic disassembly sequences, but he/she can also propose different strategies to improve the ergonomics. The methodology has been tested in a real case study to evaluate the strength points and criticalities of this approach.

Inclusion of Users with Special Needs in the Human-Centered Design of a Web-Portal

Human-Centered Design focuses on the analysis, specification and involvement of a product's end users as driving elements in the design process. The primary research objective of the case-study presented in this paper is to illustrate that it is essential to include users with special needs into all major steps of designing a web-portal that provides services to these special users. But how can this be accomplished in the case of users with special cognitive and affective needs? Would the “classical” Human-Centered Design Process (HCD) be sufficient or would it need to be adapted and complemented with special procedures and tools? In this paper the design team shares the strategies they adopted and the experiences they gained by including users with dyslexia in the design of the LITERACY Web-Portal. Besides providing insight into the special effort and steps needed to adapt HCD for users with special needs, the paper encourages application designers to include end-users even though - or particularly because - they have needs that are special and critical for the adoption of the product.

Does industry close the loop?

The sustainment of ‘value’ beyond products’ first-use life cycles can promote a circular and more environmentally sound economy. This includes the recovery of raw materials after a new product's end of life. More specifically, high-tech products contain manifold scarce resources such as rare earth metals, precious metals and semi-conductors. Society regards such metals as an important economic resource, underpinning the competitive advantage of national economies. This paper analyses whether industry has developed appropriate recycling process technologies for selected ‘critical metals’. The study runs a quantitative patent analysis, and identifies highly precise search terms from a qualitative expert literature review. Findings suggest that industry has begun closing the loop for certain metals and that technology suppliers, if approximated by patent output, arise mainly from Asian countries. The patent count also provides insight into the recent global metals recycling and recovery technology landscape, namely, its dynamics and top applicants.

Immune Potentiating role of Protein, Probiotic and Symbiotic Supplementation in Moulted White Leghorn Hens

This study investigated the effects of high protein, probiotic and symbiotic supplementation on the immunity of culled moulted White Leghorn hens. Cage-housed hens ( n = 240) aged about 70 weeks were moulted by including zinc in the diet. The moulted hens were randomly divided in four treatment groups: control group (G1; CP 16% in basal diet), high protein group (G2; CP 18% in basal diet), probiotic supplemented group (G3; symbiotic at a dose rate of 85 mg L−1 in drinking water + CP 16% in basal diet), and symbiotic group (G4; probiotic at a dose rate of 85 mg L−1 in drinking water + CP 16% in basal diet). Ten birds from each group were euthanised at 5% peak (5P), full peak (FP), and end of production (EP). Blood samples were taken for serum to estimate geometric mean antibody titre (GMT) against Newcastle disease virus (NDV) and egg drop syndrome (EDS) virus. Macrophages were isolated from abdominal exudates (AE) to observe their engulfment response and their nitric oxide (NO) production. 2,4-Dinitrochlorobenzene (DNCB) was inoculated on the skin of five birds in each group to evaluate the delayed type hypersensitivity response by determining the skin thickness. The overall humoral antibody GMT against NDV in the groups was higher in G2, G3 and G3 compared to G1. GMT value against EDS was higher in G2 compared to G1. A significant increase ( P ≤ 0.01) in macrophage engulfment and NO production was seen in G2 and G4 compared to the G1. The DNCB inoculated skin thickness response remained higher ( P ≤ 0.01) in G2 until FP than the other groups. A diet rich in protein or supplemented with a probiotic or a symbiotic enhances the body immunity of moulted hens.

Effect of cooking conditions on cholesterol oxidation and astaxanthin in dried salted shrimp

Dried salted shrimp is a product made from raw shrimps, which are usually cooked and dried under direct sunlight. Brine cooking is an important step during the production of dried salted shrimp as it promotes changes that affect the product's end quality. The aim of this study was to evaluate the effect of brine concentration and boiling time on cholesterol oxidation products (COPs) formation and the concomitant changes in astaxanthin content and fatty acid profile in shrimp during cooking, sun drying, and storage. Boiling conditions did not affect COPs formation in shrimp after cooking. However, increased brine concentration and boiling time promoted high astaxanthin retention in cooked shrimp. During the first 24 h of sun drying, COPs formation in dried salted shrimp was influenced by the interaction between brine concentration and boiling time; in fact, the lowest COPs levels were observed in samples boiled at low brine concentration and short cooking times, as well as those boiled in brine with high salt concentration and long cooking times. Most astaxanthin (ca. 78%) present in cooked shrimp was degraded during solar drying. During storage, PUFA decreased, and a concomitant astaxanthin degradation and COPs formation in dried salted shrimp were observed. Neither boiling time nor storage at dark of dried salted shrimp prevented these changes.Practical applications: The content of oxysterols in cooked dried shrimps can be minimized by optimizing the processing conditions to minimize the oxidation. This is useful for processors and consumers to reduce the intake of these toxic forms of cholesterol.COPs and astaxanthin in dried shrimp were analysed during cooking, solar drying and storage. The COPs content in dried shrimp showed a dramatic increase after solar drying. During the first 24 h of sun drying, COPs formation in dried salted shrimp was influenced by the brine concentration and boiling time.

Due-date assignment for multi-server multi-stage assembly systems

In this paper, we attempt to present a constant due-date assignment policy in a multi-server multi-stage assembly system. This system is modelled as a queuing network, where new product orders are entered into the system according to a Poisson process. It is assumed that only one type of product is produced by the production system and multi-servers can be settled in each service station. Each operation of every work is operated at a devoted service station with only one of the servers located at a node of the network based on first come, first served (FCFS) discipline, while the processing times are independent random variables with exponential distributions. It is also assumed that the transport times between each pair of service stations are independent random variables with generalised Erlang distributions. Each product's end result has a penalty cost that is some linear function of its due date and its actual lead time. The due date is calculated by adding a constant to the time that the order enters into the system. Indeed, this constant value is decided at the beginning of the time horizon and is the constant lead time that a product might expect between the time of placing the order and the time of delivery. For computing the due date, we first convert the queuing network into a stochastic network with exponentially distributed arc lengths. Then, by constructing an appropriate finite-state continuous-time Markov model, a system of differential equations is created to find the manufacturing lead-time distribution for any particular product, analytically. Finally, the constant due date for delivery time is obtained by using a linear function of its due date and minimising the expected aggregate cost per product.

Strategic sourcing for the short-lifecycle products

Abstract Motivated by the sourcing of integrated circuits in the electronics industry, we study sourcing strategies for short-lifecycle products with two substitutable parts. The first part, referred to as the fast part, is highly responsive while having negligible fixed cost but high variable cost. The second part, referred to as the slow part, is opposite in these properties. We build models starting with the fast part to target the initial market, then switching to the pre-ordered slow part for volume production, and eventually transitioning back to the fast part until the product's end of lifecycle. Assuming an optional second order for the slow part, we model the sourcing process by a two-stage stochastic program. The thresholds for the fixed costs and the optimal ordering policies for the two orders are exactly derived. Assuming the demand throughout the product lifecycle as a multivariate Normal distribution, we approximately compute the policy parameters and expected profit for the two-order problem. In comparison to the fast-part only strategy and one-order slow part strategy, the second order of the slow part could be of great value if the demand correlation across time is high and/or the cost difference between the two parts is large. We also study the joint impact of fixed cost and leadtime as well as demand variation on the sourcing strategies.

Support a Science of Performance Improvement

iven the many challenges facing educa tion, it is natural to look to our na tion's research and development ca pacity to point the way. Even at its best, however, extant education re search today only weakly informs the complex processes involved in improv ing teaching and learning. We simply lack the necessary infrastructure to guide the transfor mations we need. This isn't due to an absence of activity. An indus try of education researchers is -identifying problems and developing new concepts. Individual educators regularly experiment with new practices in their class rooms, and school districts are constantly introducing new programs. Individual consultants and commer cial firms market new services, as state and federal policies incentivize new activity, and foundations pro mote bold new solutions seeking to reinvent the in stitutional enterprise. In short, an impressive array of individual projects focuses on many different issues. Taken as a whole, however, this enterprise isn't leading to solutions for major educational problems. We must reengineer both how we carry out education R&D and the institutional environments in which this work occurs if we want to achieve more produc tive ends. Something new and quite different must emerge if we are to confront educational challenges successfully.

Dynamics of innate immune response in Gallus domesticus using two methods of induced molting

The aim of this study was to compare the ability of laying hen abdominal macrophages during the second production cycle by using two different methods of induced molting. Two groups of Single Comb White Leghorn hens were induced to molt at the end of their first production cycle using feed restriction and ZnO supplementation. Macrophages were isolated from the abdomen and in vitro cytotoxic ability, at which point macrophage bactericidal moiety nitric oxide (NO) was recorded. Serum IgM and IgG titers against sheep red blood cells (SRBC) were determined at various stages: before molting (BM), 5% production level (5P), peak production stage (PP) and at the end of production (EP) level after fast and Zn-induced molt. Macrophages adherence percentage remained unaffected ( p ≤ 0.05) during all production cycles, whereas the macrophage engulfment percentage and engulfment/cell was significantly higher ( p ≤ 0.05) at PP in both fast and Zn-induced molted groups, as compared to all other studied stages. Macrophage NO production was increased ( p ≤ 0.05) at PP and after SRBC and lipopolysaccrides (LPS) stimulus, when molted with ZnO supplementation. Serum total antibody titer against SRBC increased serum IgG and IgM titers during the second production cycle by Zn-induced molt. However, molting stress greatly reduced IgG and IgM production at the 5P stage. Serum Zn concentration increased with the onset of production but decreased at the EP stage irrespective of their molting regimes. Our results validate the strengthened innate and acquired immune response during the second production cycle after Zn-induced molting instead of fasting.