Delaying Change: Examining How Industry and Managerial Turbulence Impact Structural Realignment

This paper examines when firms pursue structural realignment through business unit reconfiguration, specifically by recombining business units. Our results refine and extend contingency theory and studies of organization design by drawing on theories of decision avoidance and delay to describe environmental conditions when firms pursue or postpone structural realignment. Our empirical analysis of 46 firms from 1978 to 1997, operating within the U.S. medical device and pharmaceutical sectors, demonstrates that while decision makers initiate structural recombination during periods of industry growth (i.e., munificence), they reduce their recombination efforts during periods of industry turbulence (i.e., dynamism), and managerial turbulence (i.e., growth in top management team size). We also find evidence that firms delay realignment and bide their time for better environmental conditions of declining turbulence and industry growth before pursuing more structural realignment. Together, these findings suggest that decision makers often delay initiating structural recombination until they can effectively process information and assess how structural changes will help them realign the organization to the environment

Mechanisms of Signal Transduction by Ethylene: Overlapping and Non-Overlapping Signalling Roles in a Receptor Family

The plant hormone ethylene regulates growth and development as well as responses to biotic and abiotic stresses. Over the last few decades, key elements involved in ethylene signal transduction have been identified through genetic approaches, these elements defining a pathway that extends from initial ethylene perception at the endoplasmic reticulum to changes in transcriptional regulation within the nucleus. Here, we present our current understanding of ethylene signal transduction, focusing on recent developments that support a model with overlapping and non-overlapping roles for members of the ethylene receptor family. We consider the evidence supporting this model for sub-functionalization within the receptor family, and then discuss mechanisms by which such a sub-functionalization may occur. To this end, we consider the importance of receptor interactions in modulating their signal output and how such interactions vary in the receptor family. In addition, we consider evidence indicating that ethylene signal output by the receptors involves both phosphorylation-dependent and phosphorylation-independent mechanisms. We conclude with a current model for signalling by the ethylene receptors placed within the overall context of ethylene signal transduction

HSPs under Abiotic Stresses

Different organisms respond to the altered environmental conditions by different ways. Heat shock proteins’ (HSPs) production is one among the different defense mechanisms which defend the photosystem II and thylokoid membrane in plants. There are different types of HSPs based on their size, that is, high molecular weight (60–100 kDa) and low molecular weight heat shock proteins (15–30 kDa). Small HSPs are further classified based on their localization and role in different sub-cellular organelles. Cp-sHSPs are the chloroplast-specific small HSPs that protect the photosystem II and thylokoid membrane. A model to control the Cp-sHSPs in Chenopodium album has been put forward in this chapter. According to this model, Cp-sHSPs of Chenopodium album are created in cytoplasm and are moved toward chloroplast. The transit peptide is removed on reaching to the target sub-cellular organelle, that is, chloroplast and the premature Cp-sHSPs are converted into mature ones which have multiple roles under different abiotic stress conditions

Tomato post-harvest fruit ripening in Pakistan : effect of methylcyclopropene (1-MCP) in inhibiting ripening gene expression

Short shelf life of tomato fruits, with the unavailability of modernized handling/storage and transport practices causes ~30-40 % of yield loss which leads to great financial burden on the import of Pakistani tomatoes. There is an urgent need to adapt an easy and cost effective applicable technology for increasing the shelf life of fully ripened tomato fruits by inhibiting ethylene perception that leads to ripening and decay. This study aims to evaluate the effectiveness of ethylene perception inhibitor 1-methylcyclopropene (1-MCP) on ripening of tomatoes. Physiological and molecular parameters were recorded to analyse the inhibitory effect of 1-MCP. Green tomatoes were harvested and treated with 1-MCP for 24 h and 8 days. Results of the physiological data based on colour, weight, and firmness of the fruits showed a significant delay in the onset of ripening after 1-MCP treatment. 1-MCP is known to block ethylene receptors, therefore, we used different ethylene and ripening related genes as markers to prove that 1-MCP potentially delayed tomato fruit ripening by inhibiting the ethylene pathway that in turn downregulated the ripening signalling pathway genes. Therefore, this study provides evidence that 1-MCP can effectively be used as an alternative to reduce the post-harvest tomato yield losses in Pakistan with slight optimization on the method to suit the different varieties of local tomatoes

The ARGOS Gene Family Functions in a Negative Feedback Loop to Desensitize Plants to Ethylene

Ethylene plays critical roles in plant growth and development, including the regulation of cell expansion, senescence, and the response to biotic and abiotic stresses. Elements of the initial signal transduction pathway have been determined, but we are still defining regulatory mechanisms by which the sensitivity of plants to ethylene is modulated. We report here that members of the ARGOS gene family of Arabidopsis, previously implicated in the regulation of plant growth and biomass, function as negative feedback regulators of ethylene signaling. Expression of all four members of the ARGOS family is induced by ethylene, but this induction is blocked in ethylene-insensitive mutants. The dose dependence for ethylene induction varies among the ARGOS family members, suggesting that they could modulate responses across a range of ethylene concentrations. GFP-fusions of ARGOS and ARL localize to the endoplasmic reticulum, the same subcellular location as the ethylene receptors and other initial components of the ethylene signaling pathway. Seedlings with increased expression of ARGOS family members exhibit reduced ethylene sensitivity based on physiological and molecular responses

Fatty acid profiling and physiochemical characterization of Chlorella sorokiniana potentially used for biofuel production

Rising oil prices and climate change have resulted in more emphasis on research into renewable biofuels. In this study, different water samples were collected from local vicinities for the isolation of local isolates of microalgae to check their potential towards the production of biofuel by the addition of different chemical substrates. Five different concentrations of ascorbic acid and iron (III) chloride (0, 1, 2.5, 5 & 10 µM) are used as substrates. Microscopic analysis evaluated that samples belong to genus Chlorella and further molecular identification showed that the samples are C. sorokiniana. Among all the concentrations of ascorbic acid 2.5 µM is most effective against the C. sorokiniana strain 1 (Safari Wildlife Park, Lahore) and C. sorokiniana strain 2 (Bahria Town, Lahore) while C. sorokiniana Strain 3 (SukhChane Society, Lahore) responded at 2.5 & 5 µM in term of biomass production. FeCl3 (2.5 µM) is effective against C. sorokiniana strain 1 while the growth of C. sorokiniana strain 2 and C. sorokiniana Strain 3 is inhibited. Lipid content analysis showed that only the C. sorokiniana strain 1 shows effective results at 1 & 2.5 µM of ascorbic acid and FeCl3 , respectively. Those concentrations which give the significant results of lipid production were preceded for fatty acid profiling. Results indicate that the C. sorokiniana strain 1 can be considered as a source of alpha-linolenic acid; the basic constituent of biofuel production. In this study, it is concluded that C. sorokiniana strain 1 is useful for the production of environment friendly biofuel

A Randomized Controlled Trial of a Research-Tested Mobile Produce Market Model Designed to Improve Diet in Under-Resourced Communities: Rationale and Design for the Veggie Van Study

Mobile produce markets are increasingly popular retail vendors used for providing access to fresh fruits and vegetables (F&V) in under-resourced communities; however, evaluation is limited due to design and implementation challenges. This protocol presents the original design of a randomized control trial aimed at assessing the effectiveness of the evidence-based Veggie Van (VV) mobile market model. Nine US community partner organizations were asked to partner with four community sites serving lower-income areas. Sites are randomized to either intervention or control. Intervention sites will host a mobile market for one year while the control sites will host planning events, with the goal to open a market afterward. Eligible participants are aged ≥ 18, the primary household shopper, live nearby/regularly frequent the site, and have expressed interest in learning about a mobile market. The primary outcome, F&V consumption, will be assessed via dietary recall at baseline and 12 months and compared between the intervention and control sites. This research advances work on the VV model and methods for mobile market evaluation with the addition of more robust measures and the study design. Determining the effectiveness of the VV model is imperative to justify taking it to scale to enhance the impact of mobile markets