scholarly journals Potential Role of Nitrite for Abiotic Fe(II) Oxidation and Cell Encrustation during Nitrate Reduction by Denitrifying Bacteria

2013 ◽  
Vol 80 (3) ◽  
pp. 1051-1061 ◽  
Author(s):  
Nicole Klueglein ◽  
Fabian Zeitvogel ◽  
York-Dieter Stierhof ◽  
Matthias Floetenmeyer ◽  
Kurt O. Konhauser ◽  
...  
Keyword(s):  
Extracellular Polymeric Substances ◽  
Potential Role ◽  
Paracoccus Denitrificans ◽  
Culture Media ◽  
Content Type ◽  
Lectin Staining ◽  
Nitrate Reducers ◽  
Close Proximity ◽  
Oxidation Mechanisms

ABSTRACTMicroorganisms have been observed to oxidize Fe(II) at neutral pH under anoxic and microoxic conditions. While most of the mixotrophic nitrate-reducing Fe(II)-oxidizing bacteria become encrusted with Fe(III)-rich minerals, photoautotrophic and microaerophilic Fe(II) oxidizers avoid cell encrustation. The Fe(II) oxidation mechanisms and the reasons for encrustation remain largely unresolved. Here we used cultivation-based methods and electron microscopy to compare two previously described nitrate-reducing Fe(II) oxidizers (Acidovoraxsp. strain BoFeN1 andPseudogulbenkianiasp. strain 2002) and two heterotrophic nitrate reducers (Paracoccus denitrificansATCC 19367 andP. denitrificansPd 1222). All four strains oxidized ∼8 mM Fe(II) within 5 days in the presence of 5 mM acetate and accumulated nitrite (maximum concentrations of 0.8 to 1.0 mM) in the culture media. Iron(III) minerals, mainly goethite, formed and precipitated extracellularly in close proximity to the cell surface. Interestingly, mineral formation was also observed within the periplasm and cytoplasm; intracellular mineralization is expected to be physiologically disadvantageous, yet acetate consumption continued to be observed even at an advanced stage of Fe(II) oxidation. Extracellular polymeric substances (EPS) were detected by lectin staining with fluorescence microscopy, particularly in the presence of Fe(II), suggesting that EPS production is a response to Fe(II) toxicity or a strategy to decrease encrustation. Based on the data presented here, we propose a nitrite-driven, indirect mechanism of cell encrustation whereby nitrite forms during heterotrophic denitrification and abiotically oxidizes Fe(II). This work adds to the known assemblage of Fe(II)-oxidizing bacteria in nature and complicates our ability to delineate microbial Fe(II) oxidation in ancient microbes preserved as fossils in the geological record.

Revitalising Waqf (endowment) lands for agribusiness: potentials of the anchor company models

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Norfaridah Ali Azizan ◽  
Amirul Afif Muhamat ◽  
Sharifah Faigah Syed Alwi ◽  
Husniyati Ali ◽  
Amalia Qistina Casteneda Abdullah
Keyword(s):  
Household Income ◽  
Design Methodology ◽  
Potential Role ◽  
Islamic Law ◽  
Living Condition ◽  
Previous Literature ◽  
Content Type ◽  
Muslim Countries ◽  
The Right

PurposeWaqf (endowment) lands constitute as among the highest types of waqf (endowment) properties in Malaysia; yet it is still unable to reach its maximum potential due to various challenges such as capital, location, legal and administrative issues. Therefore, this study intends to explore these issues by focussing on the two states in Malaysia (Selangor and Perak) that have fertile lands but different management authorities.Design/methodology/approachThere were series of interviews that had been conducted with ten (10) key informants who are experts and practitioners in the areas of Shariah (Islamic law), farming, agribusiness, land management and waqf.FindingsFindings exhibit that constraints and challenges that had been highlighted in the previous literature still exist (although some improvements had been made), but there is emerging theme that the study intends to highlight which is on the needs to secure market for the agribusiness produce and the potential role of anchor company in the agribusiness. It is pertinent that for agribusiness to thrive, selecting the right anchor company that has the capacity to address the challenges is necessary. This study posits two anchor company models (Waqf Trustee-Anchor Company and Waqf Trustee-Anchor Company-Community Farmers) that can be applied for agribusiness on the waqf lands.Research limitations/implicationsThis study is based on the Malaysia's context influenced by specific country's features. Nevertheless, such findings can still be used as reference or benchmark by other endowment trustees in other countries especially for the Muslim countries as well as the non-Muslim countries that have significant Muslim populations.Social implicationsThe suggested models have potentials to improve the living condition of the B40 (below 40% household income) in Malaysia because the models encourage their participation in the agribusiness activities.Originality/valueThis study focusses on the agribusiness, which is rarely being given attention in previous literature in the context of endowment lands. Therefore, this article bridges the literature gap and at the same time attempts to provide suggestion to address the pertinent issue – the underutilised endowment lands.

Marketing to the “middle of the pyramid” in emerging markets using a social network perspective

2014 ◽  
Vol 9 (3) ◽  
pp. 400-423 ◽  
Author(s):  
Tendai Chikweche ◽  
Richard Fletcher
Keyword(s):  
Social Networks ◽  
Middle Class ◽  
Potential Role ◽  
Content Type ◽  
Business Executives ◽  
Advanced Economies ◽  
Sub Saharan ◽  
Corporate Social ◽  
The Impact

Purpose – The purpose of this paper is to expand knowledge about how middle class consumers in Sub-Saharan African markets behave, focusing on the potential role of social networks and the subsequent interactions that take place between these consumers and firms. Design/methodology/approach – A qualitative research method approach comprising personal interviews and observations targeted at consumers and business executives was used covering all four countries. Findings – Key findings include identification of middle of the pyramid (MOP) social networks, their impact on consumer behaviour and nature of consumer and firm interactions that take place as a result of the impact of social networks. Research limitations/implications – The sample size was restricted to 80 consumers in each of the four countries. This might limit generalisability. Practical implications – The study provides managers with insights on the potential role of social networks on marketing to the MOP in Africa. Social implications – The study provides managers with insights on the potential opportunities for corporate social responsibility solutions at the MOP. Originality/value – Research into the middle class in markets other than western advanced economies is a relatively new area of study. The majority of studies on the middle class have focused on North America and Europe ignoring the merging middle class in Africa. Hence, this research expands knowledge by providing basis for exploring new insights on the emerging marketing opportunity within the middle class in Africa.

The relationship between cooperative and competitive behavioral tendencies and trust in coworkers

2020 ◽  
Vol 8 (3) ◽  
pp. 345-360
Author(s):  
Ece Ömüriş ◽  
Ferda Erdem ◽  
Janset Özen Aytemur
Keyword(s):  
Mixed Methods Research ◽  
Potential Role ◽  
Employee Relations ◽  
Hierarchical Regression ◽  
Future Research ◽  
Content Type ◽  
Tourism Sector ◽  
Behavioral Tendencies ◽  
The Relationship

PurposeThis study aims to investigate the relationship between cooperative and competitive behavioral tendencies and trust of coworkers in organizations. Two main hypotheses were developed. The first hypothesis was that cooperativeness and trust in coworkers is positively correlated. The second hypothesis was that competitiveness and trust in coworkers is negatively correlated.Design/methodology/approachThe sample was 442 Turkish tourism sector employees in a labor-intensive industry. Two scales were used to measure trust in coworkers and cooperativeness/competitiveness. A hierarchical regression analysis was performed to understand how individuals' behavioral tendency affects their coworkers' trust in them.FindingsThe findings strongly supported the first hypothesis, in that cooperativeness was positively correlated with trust in coworkers. The second hypothesis was only partially supported because there was no significant relationship between competitiveness and the competency and trustworthiness dimensions of trust. Unselfishness aspect of trust, however, was negatively correlated with competitiveness.Research limitations/implicationsThe main contribution of this study is to show that employee cooperativeness and competitiveness can affect trust in coworker relations. However, the measurement of competitiveness and cooperativeness measurement had limitations due to differences in the culture-specific meanings of cooperation and competition. Future research employing mixed methods research is needed to further explain the content of the two tendencies and the relationship between the concepts.Originality/valueThe literature on trust and employee relations tends to focus more on the issue of trust between managers and subordinates while neglecting the complex and multifaceted structure of trust in employee–employer relations. However, new working forms mean that horizontal relations are increasingly important. Therefore, more research is needed to address the tendencies and structures that affect trust in coworkers. This study draws attention to the potential role of cooperative and competitive behaviors in trust in horizontal employee relations.

scholarly journals Serological Diagnostic Assays for HIV-Associated Tuberculosis in Sub-Saharan Africa?

2014 ◽  
Vol 21 (6) ◽  
pp. 787-790 ◽  
Author(s):  
Stephen D. Lawn
Keyword(s):  
Potential Role ◽  
Point Of Care ◽  
Antibody Responses ◽  
Sub Saharan Africa ◽  
Simple Point ◽  
Content Type ◽  
Diagnostic Assays ◽  
Hiv Coinfection ◽  
Sub Saharan

ABSTRACTIn this issue ofClinical and Vaccine Immunology, Siev and colleagues present an evaluation of antibody responses to four immunodominant proteins ofMycobacterium tuberculosisin patients with HIV-associated pulmonary tuberculosis (TB) in South Africa (M. Siev, D. Wilson, S. Kainth, V. O. Kasprowicz, C. M. Feintuch, E. Jenny-Avital, and J. J. Achkar, 21:791–798, 2014, doi:http://dx.doi.org/10.1128/CVI.00805-13). This commentary discusses the enormous need for simple point-of-care assays for tuberculosis (TB) diagnosis in patients with and without HIV coinfection in high-burden settings and considers the potential role of serological assays and the huge challenges inherent in developing and validating such assays.

Hello Kitty livery is just a glimpse of Hello Kitty experiential package

2015 ◽  
Vol 25 (1) ◽  
pp. 75-94 ◽  
Author(s):  
Stephen W. Wang ◽  
Waros Ngamsiriudom
Keyword(s):  
Purchase Intention ◽  
Potential Role ◽  
Behavioral Control ◽  
Subjective Norms ◽  
Perceived Behavioral Control ◽  
Experiential Marketing ◽  
Related Services ◽  
Content Type ◽  
Consumer Purchase Intention

Purpose – Celebrity-themed aircraft campaigns have become a popular tactic that airlines adopt as part of their experiential marketing efforts. The campaign aims at differentiating their airline from competitors through delivering and/or reforming consumers’ flying experience. The paper aims to discuss this issue. Design/methodology/approach – Based on data collected from Taiwan, this study investigated the influence of four antecedents – attitude toward celebrity-themed aircrafts, subjective norms, perceived behavioral control and celebrity worship − on purchase intention. Findings – The results revealed significant positive relationships between all four antecedents and purchase intention. Furthermore, celebrity worship changed the relationships between attitude, subjective norms, as well as perceived behavioral control and intentions. Originality/value – This study investigates the potential role of marketing program of airlines with a fictional celebrity-themed aircraft that offer immersive flying experience to consumers. The experience starts on the outside where consumers can see the aircraft painted with celebrity-themed livery, and on the inside where the consumers get to experience many celebrity-related products, services, and spirit. According to the results, airlines can influence consumer purchase intention of the airlines services by offering consumers more celebrity related services, including celebrity-themed aircraft, customized products, and limited-amount souvenirs for their patronage. The results also demonstrate that celebrity worship has a significantly moderating effect on consumers’ perception on purchase intention. The results can vary depending on the intensity of celebrity worship.

scholarly journals Staphylococcus epidermidis Bacteriophages from the Anterior Nares of Humans

2011 ◽  
Vol 77 (21) ◽  
pp. 7853-7855 ◽  
Author(s):  
Vijay Aswani ◽  
Denise M. Tremblay ◽  
Sylvain Moineau ◽  
Sanjay K. Shukla
Keyword(s):  
Staphylococcus Epidermidis ◽  
Ecological Niche ◽  
Potential Role ◽  
Human Subjects ◽  
Content Type

ABSTRACTThe role of virulent bacteriophages in staphylococcal colonization of the human anterior nares is not known. This report of lytic bacteriophages againstStaphylococcus epidermidisin the anterior nares of 5.5% of human subjects (n= 202) suggests their potential role in modulating staphylococcal colonization in this ecological niche.

Surgical innovation or surgical evolution: an ethical and practical guide to handling novel neurosurgical procedures

2004 ◽  
Vol 100 (1) ◽  
pp. 2-7 ◽  
Author(s):  
Mark Bernstein ◽  
Joseph Bampoe
Keyword(s):  
Personal Experience ◽  
Potential Role ◽  
Senior Author ◽  
Institutional Review Boards ◽  
Neurosurgical Procedures ◽  
Surgical Innovation ◽  
Content Type ◽  
Institutional Review ◽  
Fine Print

Object. Surgical innovation is an important driver of improvements in technique and technology, which ultimately translates into improvements in patients' outcomes. Nevertheless, patients may face new risks of morbidity and mortality when surgical innovation is used, and well-intentioned surgical “experimentation” on patients must be regulated and monitored. In this paper the authors examine the challenges of defining surgical innovation and briefly review the literature on this challenging subject. Methods. Using examples from the field of neurosurgery and in part from the personal experience of the senior author, the authors develop a model of levels of experimental acuity of surgical procedures and offer recommendations on how these procedures would best be regulated. Conclusions. The authors propose guidelines for determining the need for regulation of innovation. The potential role of institutional review boards in this process is highlighted.

scholarly journals Concerned protesters: from compassion to retaliation

2017 ◽  
Vol 51 (5/6) ◽  
pp. 983-1010 ◽  
Author(s):  
Paolo Antonetti ◽  
Stan Maklan
Keyword(s):  
Design Methodology ◽  
Potential Role ◽  
Unique Role ◽  
Content Type ◽  
Corporate Behavior ◽  
Stakeholder Relationships ◽  
Present Information ◽  
Key Drivers ◽  
Practical Implications

Purpose The purpose of the study is to outline the unique role of compassion in reactions to cases of irresponsible corporate behavior that present information about victims of these events. In this study, four antecedents of compassion for the victims of irresponsibility are presented, and a model that explains the consequences of this emotion is tested empirically. Design/methodology/approach Two studies test the research hypotheses using a mix of experimental and survey research. The effects are tested both in laboratory conditions, where consumers assess a fictitious case of corporate irresponsibility, and through a test of reactions to real online campaigns. Findings Compassion is one of the drivers of consumers’ anger at the culprit, playing an indirect role in decisions to retaliate against perpetrators. Four key drivers of compassion are identified in the research: the perceived suffering of the victims, the perceived similarity of the victims to the observer, victims’ derogation and the vividness of the description of the victims. Practical implications The study offers insights both for campaigners wishing to instigate boycotts and organizations managing complex stakeholder relationships following a crisis. Insights on the role of compassion and its antecedents lead to more effective communications able to heighten or dampen this emotion. Originality/value Existing research offers contrasting views on the potential role of compassion in reactions to injustices. This study presents a novel account that clarifies previous findings and extends our knowledge of causes and consequences of compassion.

Inhibition of gastrin release by gastric inhibitory peptide mediated by somatostatin

1986 ◽  
Vol 250 (3) ◽  
pp. G331-G335 ◽  
Author(s):  
M. M. Wolfe ◽  
G. M. Reel
Keyword(s):  
Culture Medium ◽  
Potential Role ◽  
Culture Media ◽  
Antral Mucosa ◽  
Gastrin Release ◽  
Short Term ◽  
Inhibitory Peptide ◽  
Gastric Inhibitory Peptide ◽  
Krebs Henseleit Buffer

The present studies were directed to examine the effect of gastric inhibitory peptide (GIP) on gastrin release and to determine the potential role of somatostatin in mediating this effect, utilizing rat antral mucosa in short-term tissue culture. Antral mucosa was incubated at 37 degrees C in Krebs-Henseleit buffer (pH 7.4) continuously gassed with 95% O2-5% CO2. Inclusion of carbachol (2.5 X 10(-6) M) in the culture medium increased media gastrin concentrations from 3.29 +/- 0.76 (SE) (control) to 6.77 +/- 0.76 ng/mg tissue prot (P less than 0.02). Rat antral mucosa was then incubated in the presence of GIP (10(-10) to 10(-7) M) to determine its effect on carbachol-stimulated gastrin release. GIP significantly inhibited carbachol-stimulated gastrin release into the culture media at all concentrations examined. To determine whether inhibition of carbachol-stimulated gastrin release by GIP was mediated by somatostatin, antral mucosa was incubated in the presence of carbachol, GIP (10(-10) to 10(-7) M), and specific antibodies to somatostatin in excess. Inclusion of antibodies to somatostatin in the culture medium abolished the capacity of GIP (10(9) to 10(-7) M) to inhibit carbachol-stimulated gastrin release. Results of these studies indicate 1) that GIP inhibits carbachol-stimulated gastrin release and 2) that, under the conditions of these experiments, GIP inhibition of gastrin release may be mediated locally through release of antral somatostatin.

scholarly journals Ergothioneine Is a Secreted Antioxidant in Mycobacterium smegmatis

2013 ◽  
Vol 57 (7) ◽  
pp. 3202-3207 ◽  
Author(s):  
Carine Sao Emani ◽  
Monique J. Williams ◽  
Ian J. Wiid ◽  
Nicholas F. Hiten ◽  
Albertus J. Viljoen ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Mycobacterium Smegmatis ◽  
Double Mutant ◽  
Culture Media ◽  
Growth Cycle ◽  
Low Molecular Weight ◽  
Deficient Mutant ◽  
Wild Type ◽  
Content Type

ABSTRACTErgothioneine (ERG) and mycothiol (MSH) are two low-molecular-weight thiols synthesized by mycobacteria. The role of MSH has been extensively investigated in mycobacteria; however, little is known about the role of ERG in mycobacterial physiology. In this study, quantification of ERG at various points in the growth cycle ofMycobacterium smegmatisrevealed that a significant portion of ERG is found in the culture media, suggesting that it is actively secreted. A mutant ofM. smegmatislackingegtD(MSMEG_6247) was unable to synthesize ERG, confirming its role in ERG biosynthesis. Deletion ofegtDfrom wild-typeM. smegmatisand an MSH-deficient mutant did not affect their susceptibility to antibiotics tested in this study. The ERG- and MSH-deficient double mutant was significantly more sensitive to peroxide than either of the single mutants lacking either ERG or MSH, suggesting that both thiols play a role in protectingM. smegmatisagainst oxidative stress and that ERG is able to partly compensate for the loss of MSH.

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