Assessing the Generalisability of Managerial Discretion:An Empirical Investigation in the Arab World

The purpose of this paper is to examine the generalizability of national-level managerial discretion and to assess whether the national context play a role in changing mainstream research findings. Based on a sample of three Arabian countries and using a panel of prominent cross-cultural scholars who provided 138 discretion scores for the sampled countries, we replicate the national framework of Crossland and Hambrick (2011) in a new cultural context. The cultural dimensions were measured via survey responses of 375 middle-managers based on House et al. (2004) cultural practices scale. Consistent with Crossland and Hambrick (2011), we demonstrate that individualism and uncertainty tolerance have the same positive effect on CEOs discretion even in a different cultural setting. In contrast, we show that power distance has a positive and significant effect on managerial discretion. Our results indicate that executives can take idiosyncratic and bold actions to the extent to which the cultural environment allows them to do so. Accordingly, we contribute by showing the importance of the national setting in affecting the generalizability of discretion findings

Strategizing in a Focused Context:Managerial Discretion in the Arab World

The purpose of our study is to broaden the national-level construct of managerial discretion and to investigate the effect of cultural practices on executive discretion. Based on a sample of six Arabian countries and using a panel of prominent cross-cultural scholars who provided 262 discretion scores for the sample countries, we replicate and extend the national framework of Crossland and Hambrick (2011) in a new cultural context. The cultural dimensions were measured using survey responses of middle-managers based on House et al. (2004) cultural practices scale. We extend the national-level framework of managerial discretion and find that an encompassing array of cultural practices play a crucial role in shaping the degree of discretion provided to CEOs. We empirically demonstrate that power distance, future and performance orientation along with gender egalitarianism and assertiveness has positive relationships with managerial discretion. However, institutional collectivism, uncertainty avoidance and humane orientation negatively affect the degree of discretion provided to CEOs. Our study fills a gap in the literature regarding the national-level framework of managerial discretion. Our results indicate that executives can take idiosyncratic and bold actions to the extent to which the cultural environment allows them to do so. Also, we discover new national-level antecedents of managerial discretion that haven’t been considered in earlier studies and confirm the context dependency of this concept

Non Parametric Distributed Inference in Sensor Networks Using Box Particles Messages

This paper deals with the problem of inference in distributed systems where the probability model is stored in a distributed fashion. Graphical models provide powerful tools for modeling this kind of problems. Inspired by the box particle filter which combines interval analysis with particle filtering to solve temporal inference problems, this paper introduces a belief propagation-like message-passing algorithm that uses bounded error methods to solve the inference problem defined on an arbitrary graphical model. We show the theoretic derivation of the novel algorithm and we test its performance on the problem of calibration in wireless sensor networks. That is the positioning of a number of randomly deployed sensors, according to some reference defined by a set of anchor nodes for which the positions are known a priori. The new algorithm, while achieving a better or similar performance, offers impressive reduction of the information circulating in the network and the needed computation times

Atherosusceptible Shear Stress Activates Endoplasmic Reticulum Stress to Promote Endothelial Inflammation.

Atherosclerosis impacts arteries where disturbed blood flow renders the endothelium susceptible to inflammation. Cytokine activation of endothelial cells (EC) upregulates VCAM-1 receptors that target monocyte recruitment to atherosusceptible regions. Endoplasmic reticulum (ER) stress elicits EC dysregulation in metabolic syndrome. We hypothesized that ER plays a central role in mechanosensing of atherosusceptible shear stress (SS) by signaling enhanced inflammation. Aortic EC were stimulated with low-dose TNFα (0.3 ng/ml) in a microfluidic channel that produced a linear SS gradient over a 20mm field ranging from 0-16 dynes/cm2. High-resolution imaging of immunofluorescence along the monolayer provided a continuous spatial metric of EC orientation, markers of ER stress, VCAM-1 and ICAM-1 expression, and monocyte recruitment. VCAM-1 peaked at 2 dynes/cm2 and decreased to below static TNFα-stimulated levels at atheroprotective-SS of 12 dynes/cm2, whereas ICAM-1 rose to a maximum in parallel with SS. ER expansion and activation of the unfolded protein response also peaked at 2 dynes/cm2, where IRF-1-regulated VCAM-1 expression and monocyte recruitment also rose to a maximum. Silencing of PECAM-1 or key ER stress genes abrogated SS regulation of VCAM-1 transcription and monocyte recruitment. We report a novel role for ER stress in mechanoregulation at arterial regions of atherosusceptible-SS inflamed by low-dose TNFα

How Formal and Informal Institutions of Middle Eastern Countries Influence Managerial Discretion: An Empirical Investigation

Managerial discretion is the focal theme bridging the clash between two schools of thoughts; whether executives have greater influence on their firms’ outcomes or other factors restrain their actions (Hambrick & Finkelstein, 1987). It is argued that constraints come from inertial, normative and environmental forces (e.g. DiMaggio & Powell, 1983). Of these restraints is the institutional environment in which a firm is headquartered. Our paper falls within this research stream and provides an extension for Crossland and Hambrick (2007, 2011) work. We investigate the national level of discretion in new cross-cultural contexts, provide deeper understanding of its concept, and shed the light on undiscovered discretion’s antecedents and consequences. We adopt a quantitative approach in which questionnaires represent our data collection instrument. We anticipate that in high discretion countries firms tend to follow what Miles & Snow (1978) labeled ‘Prospector’ strategy as opposed to low discretion countries in which firms incline to implement a ‘Defender’ strategy

Flourescent, online monitoring of PLGA degradation for regenerative medicine applications

Degradable polymers such as poly(lactic-co-glycolic acid) (PLGA) are frequently chosen for tissue engineering, due to their ease of production, controllable degradation rates and Food and Drug Administration (FDA) approval. Within tissue engineering it is essential that the degradation profile of such biomaterials is understood and measured both in vitro and in vivo. The majority of techniques currently undertaken to study degradation are however destructive, leading to an over reliance on end point analysis. This study therefore defines a method of fluorescently tagging PLGA, via the addition of reactive amine groups and subsequent isothiocyanate reactions, with the purpose of monitoring degradation profiles through non-destructive techniques. The amine grafting and fluorescent labelling of the PLGA was confirmed using both X-ray photospectrometry and high performance liquid chromatography. The modification of the PLGA also had no significant effect on molecular weight or the hydrophilicity of the polymer. Both the release of fluorescent by-products and the changes in fluorescence retention within the modified PLGA were observed to be highly correlated to the changes in physical weight. This paper therefore demonstrates a novel method for the online and non-destructive monitoring of polymer degradation through the incorporation of a fluorescent marker, which can decrease the reliance on end point analysis and reduce the number of samples required both in vitro and in vivo

Intra-Cultural Variation, Zone of Acceptance and Managerial Discretion: A Theoretical Discussion

This paper examines the theoretical relationship between intra-cultural variation and managerial discretion. Research into the degree of discretion, or latitude of actions, has primarily focused on the individual-, organizational-, and industry-level factors, which either allow or constrain executives to take strategic actions. Despite, the recent attempt to discover the impact of national culture, mainly values, on managerial discretion, culture has been studied on an aggregate level by assuming spatial homogeneity within a country. However, recent evidences have shown that intra-cultural variation could be as salient as or sometimes even more than inter-country variation, yet there has been no discussion on its potential association with managerial discretion. As such, we address this gap and investigate the relationship of this cultural aspect with managerial discretion. Using institutional, stakeholder and upper echelons theories, our study proposes a strong relationship between intra-cultural variation and managerial discretion. Therefore, our study contributes to the strategic management and culture literature by providing a more nuanced understanding of such relationship and most importantly by introducing a new national construct that could play an important role in the strategic decision making of business executives

Assessing Miles and Snow Typology through the Lens of Managerial Discretion: How National-Level Discretion Impact Firms Strategic Orientation

Studies on the implications of managerial discretion have mainly focused on the firm, executive or industry level attributes. Little work has tackled the national-level aspect of this construct and its potential implication on firm strategies. We seek to theoretically establish an association between the construct of managerial discretion and firm strategic orientation from a national-level. Our theoretical analysis strongly suggests that the degree of managerial discretion available to executives in each country could have a strong influence on companies’ competitive strategy. We contribute to the strategic management field and the discretion literature by uncovering new national-level implications

Antibacterial Efficacy of Silver Diamine Fluoride Compared to Casein Phosphopeptide-Amorphous Calcium Phosphate Against Streptococcus mutans in a Biofilm Caries Model

Objective: To compare the antibacterial efficacy of silver diamine fluoride (SDF) with a product containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) against Streptococcus mutans using a biofilm caries model. Material and Methods: Twenty-seven saliva-coated dentine blocks obtained from extracted human teeth were inoculated with Streptococcus mutans monospecies biofilm in this in vitro study. The biofilms were then exposed to 10% sucrose in brain heart infusion broth eight times daily for seven days. After the biofilm growth period, the dentine blocks (n=9 per group) were treated with one of the following substances: 1) sterile saline (control), 2) 38% SDF, and 3) a product containing CPP-ACP. Then, the samples were incubated at 37ºC for 48 hours, and the numbers of viable microorganisms in the biofilms were counted and compared. ANOVA and Tukey\u27s HSD tests were used to analyze the data (p<0.05). Results: The number of viable bacteria, as determined by the number of colony-forming units (CFU mL-1) of Streptococcus mutans, was significantly reduced following treatment with SDF and the CPP-ACP product (p<0.05). However, SDF showed superior antibacterial activity compared to the CPP-ACP product (mean CFU mL-1=zero compared to 96 x106) (p<0.05). Conclusion: SDF has higher antibacterial activity against cariogenic Streptococcus mutans biofilm than the CPP-ACP product. The CPP-ACP product showed antibacterial activity, but it was limited