Environmentally Regulated Research Articles

Optimal Green Input Level for a Capital-Constrained Supply Chain Considering Disruption Risk

Under increasingly stringent environmental regulations, inadequate green input levels from manufacturers may lead to substandard emissions and production shutdown, which further results in the disruption risk of the supply chain. This work investigates a green supply chain (GSC) consisting of one environmentally regulated manufacturer and one capital-constrained retailer who faces stochastic market demand. The manufacturer needs to make decisions on the green input level, which is related to the investment cost as well as supply disruption risk. The retailer has to determine product order quantities and financing decisions. We derive the operational equilibriums for the GSC system under three scenarios: no financing, trade credit financing (TCF), and bank credit financing (BCF), and recommend the optimal financial selection for the retailer via the comparison of three financial modes. The analytical and numerical results reveal that the manufacturer should improve the green input level within the financial capability to enhance the sustainable operation level of the supply chain. In addition, we find that the capital-constrained retailer will choose financing, since either BCF or TCF will result in a higher profit than no financing. Moreover, we obtain the threshold of green input level, with which we can decide whether to choose TCF or BCF under the given corresponding parameters.

Decentralized environmental regulations and plant‐level productivity

AbstractUsing the framework provided by the Porter hypothesis, we study the impact of environmental regulations and enforcement policies on plant‐level green total factor productivity (TFP) growth and its components related to efficiency change and technical change. The detailed microdata we use are from Sweden and for the pulp and paper industry. This industry is the source of significant amounts of water and air pollution and is one of the most heavily environmentally regulated manufacturing industries. Sweden has a unique decentralized regulatory structure where the manufacturing plants have to comply with plant‐specific regulatory standards stipulated at the national level, as well as decentralized local supervision and enforcement. Our empirical results point to beneficial impacts of the environmental policies on plants' green TFP growth and sustainable production practices. We also find that political economy considerations are important, as the presence of the Green Party and aspects like plant size (with corresponding local and regional economic effects) matter in enforcement of the standards.

Caracterização produtiva e de regularização ambiental da carcinicultura na região do vale do Paraíba

A carcinicultura no Brasil se desenvolve a mais de 30 anos com períodos de ascensão e queda, contudo é um segmento consolidado na produção de proteína animal, gerando milhares de empregos e movimentando a econômica em locais com poucas oportunidades de trabalho. A produção, no Brasil, se concentra na região Nordeste, onde é produzido aproximadamente 95% do camarão cultivado no país. Essa região possui condições ambientais e climáticas favoráveis à criação de camarões. Considerando que a carcinicultura é uma atividade exercida principalmente por pequenos produtores rurais, os quais atuam com baixo capital financeiro, sem todas as regularizações ambientais necessárias e com baixo monitoramento ambiental na produção, esse trabalho tem o objetivo de realizar a caracterização da carcinicultura na região do Vale do Paraíba, e assim, proporcionar um melhor entendimento sobre a carcinicultura e sua sustentabilidade na região. Para isso, foram realizadas entrevistas “in loco” em 20 empreendimentos produtores de camarão na região. Os resultados demonstram que 40% das propriedades têm até 1 hectare de área produtiva e 55% delas possuem de 1 a 2 pessoas trabalhando na produção. Poucos empreendimentos da região estão regularizados do ponto de vista ambiental e apenas 50% deles fazem algum tipo de monitoramento nesta área. Concluir-se que a carcinicultura no Vale do Paraíba é uma atividade exercida, sobretudo, por micro e pequenos produtores. É necessário que os empreendimentos da carcinicultura busquem a regularização de suas atividades, evitando-se a paralização do negócio e prejuízos ambientais e financeiros. Além disso, é indispensável que os produtores aumentem suas capacidades de realizar um adequado monitoramento ambiental, principalmente, nos parâmetros de qualidade de água e efluentes gerados na produção do camarão. Os resultados desse estudo são de fundamental importância para subsidiar futuros estudos científicos e tecnológicos em prol da cadeia produtiva da carcinicultura.

FRUITFULL controls SAUR10 expression and regulates Arabidopsis growth and architecture

MADS-domain transcription factors are well known for their roles in plant development and regulate sets of downstream genes that have been uncovered by high-throughput analyses. A considerable number of these targets are predicted to function in hormone responses or responses to environmental stimuli, suggesting that there is a close link between developmental and environmental regulators of plant growth and development. Here, we show that the Arabidopsis MADS-domain factor FRUITFULL (FUL) executes several functions in addition to its noted role in fruit development. Among the direct targets of FUL, we identified SMALL AUXIN UPREGULATED RNA 10 (SAUR10), a growth regulator that is highly induced by a combination of auxin and brassinosteroids and in response to reduced R:FR light. Interestingly, we discovered that SAUR10 is repressed by FUL in stems and inflorescence branches. SAUR10 is specifically expressed at the abaxial side of these branches and this localized activity is influenced by hormones, light conditions and by FUL, which has an effect on branch angle. Furthermore, we identified a number of other genes involved in hormone pathways and light signalling as direct targets of FUL in the stem, demonstrating a connection between developmentally and environmentally regulated growth programs.

Operational and environmental performance in China's thermal power industry: Taking an effectiveness measure as complement to an efficiency measure

The trend toward a more fiercely competitive and strictly environmentally regulated electricity market in several countries, including China has led to efforts by both industry and government to develop advanced performance evaluation models that adapt to new evaluation requirements. Traditional operational and environmental efficiency measures do not fully consider the influence of market competition and environmental regulations and, thus, are not sufficient for the thermal power industry to evaluate its operational performance with respect to specific marketing goals (operational effectiveness) and its environmental performance with respect to specific emissions reduction targets (environmental effectiveness). As a complement to an operational efficiency measure, an operational effectiveness measure not only reflects the capacity of an electricity production system to increase its electricity generation through the improvement of operational efficiency, but it also reflects the system's capability to adjust its electricity generation activities to match electricity demand. In addition, as a complement to an environmental efficiency measure, an environmental effectiveness measure not only reflects the capacity of an electricity production system to decrease its pollutant emissions through the improvement of environmental efficiency, but it also reflects the system's capability to adjust its emissions abatement activities to fulfill environmental regulations. Furthermore, an environmental effectiveness measure helps the government regulator to verify the rationality of its emissions reduction targets assigned to the thermal power industry. Several newly developed effectiveness measurements based on data envelopment analysis (DEA) were utilized in this study to evaluate the operational and environmental performance of the thermal power industry in China during 2006–2013. Both efficiency and effectiveness were evaluated from the three perspectives of operational, environmental, and joint adjustments to each electricity production system. The operational and environmental performance changes over time were also captured through an effectiveness measure based on the global Malmquist productivity index. Our empirical results indicated that the performance of China's thermal power industry experienced significant progress during the study period and that policies regarding the development and regulation of the thermal power industry yielded the expected effects. However, the emissions reduction targets assigned to China's thermal power industry are loose and conservative.

Accelerated turnover of MHC class II molecules in nonobese diabetic mice is developmentally and environmentally regulated in vivo and dispensable for autoimmunity.

The H2-A(g7) (A(g7)) MHC class II (MHCII) allele is required for type 1 diabetes (T1D) in NOD mice. A(g7) not only has a unique peptide-binding profile, it was reported to exhibit biochemical defects, including accelerated protein turnover. Such defects were proposed to impair Ag presentation and, thus, self-tolerance. Here, we report measurements of MHCII protein synthesis and turnover in vivo. NOD mice and BALB/c controls were labeled continuously with heavy water, and splenic B cells and dendritic cells were isolated. MHCII molecules were immunoprecipitated and digested with trypsin. Digests were analyzed by liquid chromatography/mass spectrometry to quantify the fraction of newly synthesized MHCII molecules and, thus, turnover. MHCII turnover was faster in dendritic cells than in B cells, varying slightly between mouse strains. Some A(g7) molecules exhibited accelerated turnover in B cells from young, but not older, prediabetic female NOD mice. This acceleration was not detected in a second NOD colony with a high incidence of T1D. Turnover rates of A(g7) and H2-A(d) were indistinguishable in (NOD × BALB/c) F1 mice. In conclusion, accelerated MHCII turnover may occur in NOD mice, but it reflects environmental and developmental regulation, rather than a structural deficit of the A(g7) allele. Moreover, this phenotype wanes before the onset of overt T1D and is dispensable for the development of autoimmune diabetes. Our observations highlight the importance of in vivo studies in understanding the role of protein turnover in genotype/phenotype relationships and offer a novel approach for addressing this fundamental research challenge.

FDI and pollution havens: Evidence from the Norwegian manufacturing sector

This is an empirical study of the firm and country determinants of foreign direct investment (FDI) and how it is affected by the stringency of environmental regulations in host countries. We employ disaggregated data on sales by Norwegian multinationals' affiliates from 1999 to 2005 that allow such affiliates to be categorized as either efficiency-seeking (vertical) or market-seeking (horizontal) FDI. While the environmental stringency of a host country and its enforcement are found to have no effect on the average investment, we find a significant negative effect on multinationals with vertical motives. Compared to those located in lenient countries, the efficiency-seeking affiliates in more environmentally regulated countries receive less investment from their parent companies in terms of (i) equity capital, (ii) capital stock, and (iii) assets. We further find that the total exports from affiliates to parent companies in Norway decrease with the level of enforced environmental stringency in the host countries.

Measurement of market power for the environmentally regulated Korean iron and steel manufacturing industry

For industries in which where market prices of certain inputs are not available, measuring the degree of market power by using the markup over the marginal market cost may be inappropriate. With regard to the Korean iron and steel manufacturing industry, which is subject to environmental regulations, the calculation of the price of abatement capital is hindered by a lack of relevant data. To increase the reliability of market power markups, this paper estimates the restricted cost function in which abatement capital is assumed to be quasi-fixed at an optimal level and the supply relation. The degree of market power for the industry, measured as the ratio of the estimated market power markup to the supply price, was estimated to be 0.54 on average between 1982 and 2001. The results indicate that ignoring environmental regulations can overstate the degree of market power by approximately 12%.

Agricultural externalities and environmental regulation: evaluating good practice in citrus production

Economic activity takes place in a scenario characterized by an increasing number of environmental regulations aimed at bringing under control the emission of contaminating wastes. In this paper, we evaluate the impact of transforming a code of good practice in nitrogen fertilization on Spanish citrus fruit farms into an environmental regulation of compulsory fulfilment. Using data envelopment techniques, we calculate unrestricted and environmentally regulated short-run maximum profits. Both profit values are then used to compute an index of the cost of regulation. Our results suggest that the cost of shifting from a merely recommended practice to a binding rule is low. On average, the loss of profit computed is only about 4%. Furthermore, we find that farms’ overall efficiency is low and that the current gap between observed and regulated fertilization practices could be overcome by improving overall management efficiency.

Guard Cells: Transcription Factors Regulate Stomatal Movements

Recent work shows that transcription factors are necessary for stomatal movements in plants. Different members of the plant-specific R2R3-MYB transcription factor family are required for mediating stomatal opening in response to light and stomatal closure in response to darkness.

Conservation capital and sustainable economic growth

An endogenous growth model, which links pollution to ineffective input-use, is developed to examine the potential for achieving balanced growth while preserving the environment through investment in conservation capital. We derive conditions under which individual preferences for environmental quality and private incentives for investment in conservation capital can lead to non-decreasing environmental quality with balanced growth even in the absence of environmental regulations. Additionally, conditions under which investment in conservation capital can enable an environmentally regulated economy to achieve a higher rate of sustainable balanced growth than otherwise are analysed. Copyright 2005, Oxford University Press.

Environmental regulation and differential production of members of the Bdr protein family of Borrelia burgdorferi.

Borrelia burgdorferi B31MI carries 18 plasmid-carried genes that form the bdr gene family. The bdr genes of B. burgdorferi encode proteins that form three distinct subfamilies, the BdrD, BdrE, and BdrF subfamilies. bdr orthologs have been demonstrated to be carried by all Borrelia species analyzed, and their widespread distribution suggests that they play an important genus-wide functional role. The biological rationale for maintaining 18 bdr alleles has not been defined. It is our hypothesis that specific paralogs function in different environments and are differentially expressed in response to environmental conditions. As a first step in testing this hypothesis, the production patterns of the Bdr proteins in spirochetes grown under a variety of conditions were assessed through immunoblot analyses. The influence of temperature, serum deprivation, tick feeding, and the mammalian environment on Bdr production was evaluated. These analyses revealed that the synthesis of some Bdr paralogs is environmentally regulated. The production of BdrF(2,) BdrF(1), BdrE(4), and BdrE(5) were upregulated in host-adapted bacteria, while the production levels of other Bdr paralogs were influenced by temperature and serum starvation. These observations suggest that different Bdr paralogs function in different biological environments and provide insight into the biological basis for maintaining multiple members of this gene family.

Environmental regulation of biofilm formation in intensive care unit isolates of Staphylococcus epidermidis

Staphylococcus epidermidis is a common cause of prosthetic device-related infection in the intensive care unit (ICU). The environmentally regulated ica operon encodes a polysaccharide adhesin which is a key virulence determinant in the development of S. epidermidis biofilms. To evaluate the capacity of ICU S. epidermidis isolates to form biofilm, we measured biofilm production by 18 isolates associated with device-related infection and 20 contaminating isolates that were not associated with clinically diagnosed infection. Biofilm assays were performed in brain–heart infusion (BHI) medium and in BHI supplemented with salt, ethanol or subinhibitory tetracycline, all of which have the potential to promote biofilm formation. Polymerase chain reaction (PCR) was used to screen for the presence of the ica genes. A significant proportion of S. epidermidis strains associated with device-related infections (89%) were found to contain the ica locus compared with 50% of contaminating isolates ( P=0.01). However only four of 26 (15.3%) of all ica -positive isolates were biofilm-positive when grown in BHI medium, indicating that no significant association existed between the presence of the ica locus and biofilm-forming capacity, under standard growth conditions. In contrast the number of ica -positive isolates that were biofilm-positive under stress-inducing growth conditions or in the presence of subinhibitory tetracycline increased significantly to 73% ( P=0.02). These findings suggest that the presence of the ica locus alone is not sufficient for biofilm formation and that regulation of biofilm formation under altered growth conditions, which may exist in the in vivo environment, also plays a possible role in the pathogenesis of biomaterial-related S. epidermidis infections.

The influence of DNA topology on the environmental regulation of a pH-regulated locus in Salmonella typhimurium.

Salmonella typhimurium is exposed to major shifts in H+ concentration both in its natural and pathogenic environments. The organism undergoes extensive changes in gene expression in response to these pH fluctuations. A current question of regulatory biology is how a change in external pH selectively modulates transcription. We have analysed the expression of one such pH-regulated locus, aniG, and found it is controlled by several additional environmental conditions including osmolarity and oxygen. For factors such as osmolarity and anaerobiosis, an environmentally triggered change in DNA supercoiling has been suggested as a means for controlling gene expression. Thus, environmentally induced changes in DNA topology were explored as a possible common means for establishing the multiple controls on aniG. The involvement of DNA supercoiling in the genetic response of S. typhimurium to external pH has not previously been defined. This report establishes that alkaline environments lower the linking number of reporter plasmids when compared to acidic environments. A consistent pattern was then established whereby conditions or mutations leading to either increased or decreased negative supercoiling were associated with altered expression of aniG. A similar relationship was observed for another environmentally regulated locus, proU. The DNA topology effects on aniG expression were dependent on the presence of EarA, the negative regulator of aniG. These data can be explained by a model in which repressor-operator interactions are very sensitive to changes in operator conformation. These environmentally induced topological influences on operator DNA structure contribute to the magnitude of pH control exerted upon aniG.

Positive transcriptional control of mry regulates virulence in the group A streptococcus.

Transcription of the antiphagocytic M protein in the group A streptococcus (Streptococcus pyogenes) is environmentally regulated in response to CO2 and requires Mry, a trans-acting positive regulatory protein. We have examined the role of Mry in environmental regulation by analysing the factors that regulate expression of the gene that encodes Mry (mry). By employing a strategy that utilizes integrational plasmids, it was found that expression of mry requires the participation of DNA sequences that extend 473 base pairs upstream of the Mry coding region. Transcription of mry, as analysed in S1 nuclease protection assays, is initiated from two separate promoters located within this extended regulatory region. Construction and analysis of transcriptional fusions between the mry promoters and a promoterless chloramphenicol acetyltransferase gene demonstrated that mry is autoregulated and environmentally regulated in response to the level of CO2. These data suggest a model for the regulation of virulence in S. pyogenes where positive transcriptional control of mry in response to environmental stimuli regulates the expression of the M protein.

Developmental and environmental regulation of pea legumin genes in transgenic tobacco

Two distinct legumin genes (LegA1 and LegA2) which encode a major class of seed storage protein in pea were isolated from a genomic library. The cloned fragments were introduced into tobacco via Agrobacterium-mediated transformation and the regenerated plants were used to study the expression characteristics of the genes in a heterologous host. It was found that both LegA1 and LegA2 were functional members of the pea legumin gene family and that their expression was similar in both pea and transgenic tobacco. Legumin was detected only in the seed of tobacco where the primary translation products were processed in a manner analogous to that which occurs in pea. Legumin gene expression was also shown to be temporally regulated during seed development. Legumin polypeptides and mRNA began to accumulate 16 days after flowering (DAF), in contrast to the endogenous tobacco storage proteins which were apparent at 13 DAF. It was also demonstrated that the legumin genes in tobacco were environmentally regulated to the nutritional status of the plant. As has been previously shown in pea, legumin accumulation in transgenic tobacco seed was progressively reduced when the plants were grown under conditions of increasing severity of sulphur-nutrient stress. The reduced accumulation of protein was correlated with lower levels of legumin mRNA in the developing seed. Despite encoding nearly identical subunits, nucleotide sequence data for LegA1 and LegA2 showed that the similarity of their respective 5'-flanking regions was restricted to several short elements mostly within 240 bp from the start of transcription. However, a deletion series using the LegA1 gene demonstrated that 237 bp of 5'-flanking sequence was insufficient to permit the expression of the legumin gene in tobacco. The data indicated that an as yet unidentified sequence element(s) located between positions -668 and -237 was essential in re-establishing the high level of regulated gene expression observed with the full-length LegA1 gene.

Molecular analysis of a phylogenetically conserved carrot gene: Developmental and environmental regulation

Extensive studies of gene expression programs in carrot somatic embryos identified a gene, designated Dc3, that serves as a reliable molecular marker for the acquisition of embryogenic potential by carrot cells in culture. The complete sequence of a carrot genomic region, DcG3, encoding a Dc3-like mRNA, was determined. The DcG3 transcription unit contains a single intron and encodes mRNA that is expressed at high levels in embryonic tissue but is undetectable in somatic tissue of carrot. The predicted protein sequence of DcG3 is 163 amino acids and includes two approximately 50 amino acid direct repeats which in turn include additional repetitive elements with an unusual distribution of charged amino acids. Dc3 and Dc3-like mRNAs are encoded by a small divergent gene family. Furthermore, similarities of the Dc3 gene family with genes from other plant species that are expressed in response to environmental and developmental cues suggest a possible role in seed desiccation and possibly in more general water-stress responses in plants. Analysis of transgenic tobacco containing a beta-glucuronidase (GUS) reporter gene fused to a 1.7 kb 5' upstream element of DcG3 defined a promoter/enhancer complex that confers developmentally and environmentally regulated expression of GUS activity. Thus, DcG3 is phylogenetically conserved together with the trans-acting factors required for its regulated expression in transgenic tobacco.

Environmental regulation of type X collagen production by cultures of limb mesenchyme, mesectoderm, and sternal chondrocytes

We have examined whether the production of hypertrophic cartilage matrix, reflecting a late stage in the development of chondrocytes which participate in endochondral bone formation, is a result of cell lineage, environmental influence, or both. We have compared the ability of cultured limb mesenchyme and mesectoderm to synthesize type X collagen, a marker highly selective for hypertrophic cartilage. High-density cultures of limb mesenchyme from stage 23 and 24 chick embryos contain many cells that react positively for type II collagen by immunohistochemistry, but only a few of these initiate type X collagen synthesis. When limb mesenchyme cells are cultured in or on hydrated collagen gels, or in agarose (conditions previously shown to promote chondrogenesis in low density cultures), almost all initiate synthesis of both collagen types. Similarly, collagen gel cultures of limb mesenchyme from stage 17 embryos synthesize type II collagen and with some additional delay type X collagen. However, cytochalasin D treatment of subconfluent cultures on plastic substrates, another treatment known to promote chondrogenesis, induces the production of type II collagen, but not type X collagen. These results demonstrate that the appearance of type X collagen in limb cartilage is environmentally regulated. Mesectodermal cells from the maxillary process of stages 24 and 28 chick embryos were cultured in or on hydrated collagen gels. Such cells initiate synthesis of type II collagen, and eventually type X collagen. Some cells contain only type II collagen and some contain both types II and X collagen. On the other hand, cultures of mandibular processes from stage 29 embryos contain chondrocytes with both collagen types and a larger overall number of chondrogenic foci than the maxillary process cultures. Since the maxillary process does not produce cartilage in situ and the mandibular process forms Meckel's cartilage which does not hypertrophy in situ, environmental influences, probably inhibitory in nature, must regulate chondrogenesis in mesectodermal derivatives. Similarly, cultured chondrocytes from the cranial part of the sternum of the 19-day chick embryo become hypertrophic in situ while those from the caudal part do not. Based on immunofluorescence and SDS-PAGE of radiolabeled culture media, cells from both regions cultured in collagen gels produce type X collagen. These results emphasize the importance of exogenous factors in regulating the maturation of chondrocytes.