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WOS:000346545800018International audienceThe presence of plants induces strong accelerations in soil organic matter (SOM) mineralization by stimulating soil microbial activity a phenomenon known as the rhizosphere priming effect (RPE). The RPE could be induced by several mechanisms including root exudates, arbuscular mycorrhizal fungi (AMF) and root litter. However the contribution of each of these to rhizosphere priming is unknown due to the complexity involved in studying rhizospheric processes. In order to determine the role of each of these mechanisms, we incubated soils enclosed in nylon meshes that were permeable to exudates, or exudates & AMF or exudates, AMP and roots under three grassland plant species grown on sand. Plants were continuously labeled with C-13 depleted CO2 that allowed distinguishing plant-derived CO2 from soil-derived CO2. We show that root exudation was the main way by which plants induced RPE (58-96% of total RPE) followed by root litter. AMP did not contribute to rhizosphere priming under the two species that were significantly colonized by them i.e. Poa trivialis and Trifolium repens. Root exudates and root litter differed with respect to their mechanism of inducing RPE. Exudates induced RPE without increasing microbial biomass whereas root litter increased microbial biomass and raised the RPE mediating saprophytic fungi. The RPE efficiency (RPE/unit plant-C assimilated into microbes) was 3-7 times higher for exudates than for root litter. This efficiency of exudates is explained by a microbial allocation of fresh carbon to mineralization activity rather than to growth. These results suggest that root exudation is the main way by which plants stimulated mineralization of soil organic matter. Moreover, the plants through their exudates not only provide energy to soil microorganisms but also seem to control the way the energy is used in order to maximize soil organic matter mineralization and drive their own nutrient supply. (C) 2014 Elsevier Ltd. All rights reserved

Factors affecting Pakistan’s university students’ purchase intention towards foreign apparel brands

This paper aims to study factors affecting Pakistan’s university students’ purchase intention towards foreign apparel brands. Purchase intention is explained in terms of general consumer variables (normative influence,consumer confidence) and brand specific variables (perceived quality, emotional value). The sample comprised of students enrolled at two universities in major cities of Pakistan (Islamabad & Rawalpindi), with 315 participants completing the self-administered questionnaire during scheduled classes. Results reveal that susceptibility to normative influence and consumer confidence had positive impact on brand consciousness. Brand consciousness had positive impact on perceived quality of international apparel brands & emotional value thatthese brands generate. Both quality and emotional value had significant impact on purchase intention. The findings of this paper cannot be generalized to other consumer products, or other segments of society, such as children, professionals. However, results reveal that foreign apparel brands need to focus on quality andtheir brand’s emotional attributes if they want to succeed in Pakistan’s apparel market

Remediation of wastewater by biosynthesized manganese oxide nanoparticles and its effects on development of wheat seedlings

IntroductionNanoparticles play a vital role in environmental remediation on a global scale. In recent years, there has been an increasing demand to utilize nanoparticles in wastewater treatment due to their remarkable physiochemical properties.MethodsIn the current study, manganese oxide nanoparticles (MnO-NPs) were synthesized from the Bacillus flexus strain and characterized by UV/Vis spectroscopy, X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy.ResultsThe objective of this study was to evaluate the potential of biosynthesized MnO-NPs to treat wastewater. Results showed the photocatalytic degradation and adsorption potential of MnO-NPs for chemical oxygen demand, sulfate, and phosphate were 79%, 64%, and 64.5%, respectively, depicting the potential of MnO-NPs to effectively reduce pollutants in wastewater. The treated wastewater was further utilized for the cultivation of wheat seedlings through a pot experiment. It was observed that the application of treated wastewater showed a significant increase in growth, physiological, and antioxidant attributes. However, the application of treated wastewater led to a significant decrease in oxidative stress by 40%.DiscussionIt can be concluded that the application of MnO-NPs is a promising choice to treat wastewater as it has the potential to enhance the growth, physiological, and antioxidant activities of wheat seedlings

Role of plant rhizosphere across multiple species, grassland management and temperature on microbial communities and long term soil organic matter dynamics

It is increasingly being recognized that the soil microbes can mineralize recalcitrant soil organic matter (SOM) by using the fresh carbon (C) as a source of energy, a process called priming effect (PE). It has been shown mostly in lab incubations that PE can have important consequences for sequestration of organic C in soils. However, the importance of PE in C and N dynamics of ecosystems remains little known. The soil-plant interactions and rhizospheric processes can modulate the rates of PE and its consequences on C and N dynamics in an ecosystem. The objective of this thesis was to determine the role of PE in the C and N dynamics of permanent grasslands and the modulation of this role in response to management (plant clipping, fertilization) and global warming. Moreover, it was aimed to identify the microbial groups involved in PE and to unravel the way, e.g. absorption of N, root exudations and litter deposition, by which plant can induce PE. The thesis was based on a new approach allowing continuous dual labelling of multiple grassland plants with 13C- and 14C-CO2. The dual labelling permitted the separation of soil-derived CO2 from plant-derived CO2, the calculation of PE and the determination of mean age of soil-derived CO2-C. Moreover, phospholipids fatty-acids analysis (PLFA) permitted to correlate the variation of PE with changes in microbial community composition. Our work showed that the increased SOM mineralization under grasses was consistently two to three times more than that in bare soils (i.e. PE) over long term (511 days). This reveals that the PE plays key role in ecosystem CO2-C flux and indicates that a very large pool of SOM is under the control of PE. Moreover, we report that 15,000 years old organic C from an undisturbed deep soil can be mineralized after the supply of fresh C by living plants to soil microbes. This result supports the idea that the SOM in deep soils is stable due to the energy-limitation of microbes and the ‘inert' pool of organic C defined in current models is not so ‘inert' finally. The supply of N in soil-plant system through the use of fertilizer or legume decreased the PE suggesting that the C storage in soils is limited by nutrient supply. Similarly, plant clipping reduced the plant N uptake thereby PE. Collectively these results suggest synchronization between plant N uptake and SOM mineralization supporting the idea that soils under permanent plant cover function as a bank of nutrients for the plant, maximizing plant productivity and nutrient retention. An innovative method clearly showed that the root exudation is the major way by which grassland plants induce PE. Moreover, saprophytic fungi are suggested as the key actors in the mineralization of recalcitrant SOM & PE. Lastly, we developed a new theory on temperature response of SOM mineralization by taking into account the energy-limitation of microbes and the temperature-dependent inactivation of enzymes. This theory predicts a negative relationship between temperature and mineralization of recalcitrant SOM, which was supported by experimental results. This finding challenges the classical paradigm of positive relationship between temperature and recalcitrant SOM mineralization. Overall, these investigations on plant-soil systems reinforce the idea that PE and underlying mechanisms play a key role in ecosystem C and N dynamics and even suggest that this role was underestimated in lab experiments

CONVERGING DOUBLE COLONIZATION: EXPLORING SUSAN ABULHAWA'S 'AGAINST THE LOVELESS WORLD' THROUGH THE LENS OF SPIVAK'S THEORY

The present study explores the impression of intersecting double colonization in Susan Abulhawa's ‘Against the Loveless World’ through Gayatri Spivak's theoretical framework. This novel tells the story of the protagonist Nahr, a Palestinian woman who faces numerous troubles as she goes through personal and political struggles. By focusing on the merging of gender and national colonization, this research examines the experiences of Nahr, exploring her identity, agency and resistance within an intricate socio-political context. The study adds to have a better understanding of Abulhawa's narrative, stressing the alignment with Spivak's theoretical perspectives. The objective of the research is to highlight the intricacies and complexities of dual colonization and its magnitudes for marginalized personalities in the novel. It shows the significance of applying Spivak's framework to light up the complexities of dual colonization, presenting valuable understandings of the impact on colonized individuals in the text under research. The tentative conclusion of this research reveals the complex power dynamics and cultural influences, shedding light on the intricate interplay between gender and national oppression

Negotiating Identity and Socioeconomic Disparity in The Bride by Bapsi Sidhwa: A Post-modern Study

The purpose of this research is to explore the complex relationship between negotiating cultural identity and socioeconomic disparity in Bapsi Sidhwa's 'The Bride'. The present study employs Nancy Frazer's theory of social justice as a theoretical framework. The goal of the research is to show how the characters' experiences with cultural identities are closely linked to their socio-economic disparities. The research intends to elucidate the intricate processes that effect the characters' goals and reactions to social issues by utilizing Frazer's Theory of social justice. By providing comprehensions to the larger conversation on social justice within the post-partition community, this analysis develops our understanding of the intricacy present in characters’ identities and their socio-economic status. The conclusion of this research tends to explore the negotiation of identity and socio-economic disparity in post partition context by utilizing the theoretical framework of Frazer theory of social justice

IMPACT OF SELF ESTEEM & SUPPORT ON STUDENT PERFORMANCE

Education is life blood for development of country. This paper explores the impact of various factors on student performance. Data was collected from ten (10) Govt. & Private schools in Rawalpindi. Out of 1100 hundred responded 600 hundred responses inducted in this study. Simple regression employed in this study to test the hypothesis. The result concluded that both factor have significant negative relationship with student performance. In future, the difference of performance level among male and female may be explored in term of pick & drop facility, university distance from home and other responsibility due on male student as they grow

Traffic Light Detection: A cost effective approach

In last couple of decades, the technological advancements in image and video processing has brought great revolution in our life. Some of the key areas where these advancements have played a key role are: autonomous vehicles, drone technology, crowd monitoring, traffic monitoring, object tracking etc. Nowadays a lot of work is under process for improving capabilities of autonomous vehicles and driver assisted systems. Our focus in this paper is related to automated traffic light detection system with improved capabilities in terms of time complexity and accuracy. The time complexity is directly related to image or video quality with regard to resolution of video and the accuracy is often compromised because of identification of similar objects. The similar objects often appear in video frames when each frame of video is analyzed completely. In order to solve the problem of real time detection of traffic lights in a high-resolution video having 30 frames per second with a resolution of 1280 × 720, we propose an algorithm that systematically searches in middle 70% region of each frame. The proposed algorithm optimizes the search space by dividing middle region into 3. There are three methods for searching and registering a traffic light is proposed in this paper. The basic concept is at single instance a traffic light can exist on one of these three regions. These trategies help in reducing computation complexity tremendously. The Hough Circle Transform technique of image processing is exploited to accurately detect red and green circles of light in the traffic light. Efficacy of the proposed technique in terms of improved time and accuracy is demonstrated on a real dataset collected from Nexar (dashcam mobile solution provider), it encompasses different illumination conditions: day, evening, night, cludy weather and rain etc