Search results for: A. Qayyum
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 16

Search results for: A. Qayyum

16 Using Technology to Enhance the Student Assessment Experience

Authors: Asim Qayyum, David Smith

Abstract:

The use of information tools is a common activity for students of any educational stage when they encounter online learning activities. Finding the relevant information for particular learning tasks is the topic of this paper as it investigates the use of information tools for a group of student participants. The paper describes and discusses the results with particular implications for use in higher education, and the findings suggest that improvement in assessment design and subsequent student learning may be achieved by structuring the purposefulness of information tools usage and online reading behaviors of university students.

Keywords: information tools, assessment, online learning, student assessment experience

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15 Language Switching Errors of Bilinguals: Role of Top down and Bottom up Process

Authors: Numra Qayyum, Samina Sarwat, Noor ul Ain

Abstract:

Bilingual speakers generally can speak both languages with the same competency without mixing them intentionally and making mistakes, but sometimes errors occur in language selection. This quantitative study particularly deals with the language errors made by Urdu-English bilinguals. In this research, researchers have given special attention to the part played by bottom-up priming and top-down cognitive control in these errors. Unstable Urdu-English bilingual participants termed pictures and were prompted to shift from one language to another under the pressure of time. Different situations were given to manipulate the participants. The long and short runs trials of the same language were also given before switching to another language. The study is concluded with the findings that bilinguals made more errors when switching to the first language from their second language, and these errors are large in number, especially when a speaker is switching from L2 (second language) to L1 (first language) after a long run. When the switching is reversed, i.e., from L2 to LI, it had no effect at all. These results gave the clear responsibility of all these errors to top-down cognitive control.

Keywords: bottom up priming, language error, language switching, top down cognitive control

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14 Development and Evaluation of Whey-Based Drink: An Approach to Protect Environmental Pollution

Authors: Zarmina Gillani, Mulazim Hussain Bukhari, Nuzhat Huma, Aqsa Qayyum

Abstract:

Whey is a valuable by-product of dairy industry comprising of precious nutrients lactose, protein, vitamins and minerals for the human food but considered as a pollutant due to its biological activity. So, there is a need to develop nutritious whey products to overcome the problem of environmental pollution. This project was planned to develop a whey drink at different pasteurization temperatures and its quality was evaluated during storage. The result indicated that pH, acidity, total soluble solids and lactose content changed significantly (p < 0.01) due to lactic acid production during storage. Non-significant (p > 0.05) effects were detected on the protein and ash content of whey drink. Fat and viscosity changed significantly with respect to storage only. Sensory evaluation of whey drink revealed that both treatments remained acceptable while whey drink pasteurized at 75°C/30 minutes (WD2) gained more sensory score compared to whey drink pasteurized at 65°C/30minutes (WD1).

Keywords: pasteurization, sensory evaluation, storage, whey

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13 Exploitation of Variability for Salinity Tolerance in Maize Hybrids (Zea Mays L.) at Early Growth Stage

Authors: Abdul Qayyum, Hafiz Muhammad Saeed, Mamoona Hanif, Etrat Noor, Waqas Malik, Shoaib Liaqat

Abstract:

Salinity is extremely serious problem that has a drastic effect on maize crop, environment and causes economic losses of country. An advance technique to overcome salinity is to develop salt tolerant geno types which require screening of huge germplasm to start a breeding program. Therefore, present study was undertaken to screen out 25 maize hybrids of different origin for salinity tolerance at seedling stage under three levels of salt stress 250 and 300 mM NaCl including one control. The existence of variation for tolerance to enhanced NaCl salinity levels at seedling stage in maize proved that hybrids had differing ability to grow under saline environment and potential variability within specie. Almost all the twenty five maize hybrids behaved varyingly in response to different salinity levels. However, the maize hybrids H6, H13, H21, H23 and H24 expressed better performance under salt stress in terms of all six characters and proved to be as highly tolerant while H22, H17 H20, H18, H4, H9, and H8 were identified as moderately tolerant. Hybrids H14, H5, H11 and H3 H12, H2, were expressed as most sensitive to salinity suggesting that screening is an effective tool to exploit genetic variation among maize hybrids and salt tolerance in maize can be enhanced through selection and breeding procedure.

Keywords: salinity, hybrids, maize, variation

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12 Evaluation of Genetic Diversity for Salt Stress in Maize Hybrids (Zea Mays L.) at Seedling Stage

Authors: Abdu Qayyum, Hafiz Muhammad Saeed, Mamoona Hanif, Etrat Noor, Waqas Malik, Shoaib Liaqat

Abstract:

Salinity is extremely serious problem that has a drastic effect on maize crop, environment and causes economic losses of country. An advance technique to overcome salinity is to develop salt tolerant geno types which require screening of huge germ plasm to start a breeding program. Therefore, present study was undertaken to screen out 25 maize hybrids of different origin for salinity tolerance at seedling stage under three levels of salt stress 250 and 300 mM NaCl including one control. The existence of variation for tolerance to enhanced NaCl salinity levels at seedling stage in maize proved that hybrids had differing ability to grow under saline environment and potential variability within specie. Almost all the twenty five maize hybrids behaved varyingly in response to different salinity levels. However, the maize hybrids H6, H13, H21, H23 and H24 expressed better performance under salt stress in terms of all six characters and proved to be as highly tolerant while H22, H17 H20, H18, H4, H9, and H8 were identified as moderately tolerant. Hybrids H14, H5, H11 and H3 H12, H2, were expressed as most sensitive to salinity suggesting that screening is an effective tool to exploit genetic variation among maize hybrids and salt tolerance in maize can be enhanced through selection and breeding procedure.

Keywords: salinity, hybrids, maize, variation

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11 A Comparative Study on the Synthesis, Characterizations and Biological (Antibacterial and Antifungal) Activities of Zinc Doped Silica Oxide Nanoparticles Based on Various Solvents

Authors: Muhammad Arshad, Ghulam Hussain Bhatti, Abdul Qayyum

Abstract:

Zinc-doped silica oxide nanoparticles having size 7.93nm were synthesized by the deposition precipitation method by using different solvents (acetonitrile, n-hexane, isoamylalchol). Biological potential such as antibacterial activities against Bacillussubtilusand Escherichia coli, and antifungal activities against Candida parapsilosis and Aspergilusniger were also investigated by Disc diffusion method. Different characterizations techniques including Fournier Transmission Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), Thermo-gravimeteric Analysis (TGA), Atomic forced microscopy (AFM), and Dynamic Light Scattering (DLS) were used. FT-IR characterization confirmed the presence of metal oxide bond (SiO2) while XRD showed the hexagonal structure. SEM and TEM characterization showed the morphology of nanoparticles. AFM study showed good particle size distribution as depicted by a histogram. DLS study showed the gradual decease in the size of nanoparticles from 24.86nm to 13.24 nm. Highest antibacterial activities revealed by acetonitrile solvents (6%and 4.5%) followed by isoamylalchol (3% and 2.4%) while n-hexane solvent showed the lowest activity (2%and 1%) respectively. Higher antifungal activities exhibited by n-hexane (0.34 % and 0.43%) followed by isoamylalchol (0.27% and 0.19%) solvent while acetonitrile (0.21% and 0.17%) showed least activity respectively. Statistical analysis by using one-way ANOVA also indicated the significant results of both biological activities.

Keywords: nanoparticles, precipitation methods, antibacterial, antifungal, characterizations

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10 Role of Moderate Intensity Exercises in the Amelioration of Oxidant-Antioxidant Status and the Levels of Inflammatory Cytokines in Rheumatoid Arthritis Patients

Authors: Somaiya Mateen, Shagufta Moin, Abdul Qayyum, Atif Zafar

Abstract:

Cytokines and reactive species play an important role in the pathophysiology of rheumatoid arthritis (RA). This study was done to determine the levels of reactive oxygen and nitrogen species (ROS and RNS), inflammatory cytokines and the markers of protein, DNA and lipid oxidation in the blood of RA patients, with the aim to study the antioxidant and anti-inflammatory role of moderate intensity exercises in the management of RA. RA patients were subdivided into two groups- first group (n=30) received treatment with conventional RA drugs while the second group (n=30) received moderate exercise therapy along with the conventional drugs for a period of 12 weeks. The levels of ROS, RNS, inflammatory cytokines and markers of biomolecule oxidation were monitored before and after 12 weeks of treatment. RA patients showed a marked increase in the levels of ROS, RNS, inflammatory cytokines, lipid, protein and DNA oxidation as compared to the healthy controls. These parameters were ameliorated after treatment with drugs alone and exercise combined with drugs, with the amelioration being more significant in patients given drugs along with the moderate intensity exercise treatment. In conclusion, the role of ROS, RNS and inflammatory cytokines in the pathogenesis of RA has been confirmed by this study. These may also serve as potential biomarker for assessing the disease severity. Finally, the addition of moderate intensity exercises in the management of RA may be of great value.

Keywords: rheumatoid arthritis, reactive oxygen species, inflammatory cytokines, moderate intensity exercises

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9 High Catalytic Activity and Stability of Ginger Peroxidase Immobilized on Amino Functionalized Silica Coated Titanium Dioxide Nanocomposite: A Promising Tool for Bioremediation

Authors: Misha Ali, Qayyum Husain, Nida Alam, Masood Ahmad

Abstract:

Improving the activity and stability of the enzyme is an important aspect in bioremediation processes. Immobilization of enzyme is an efficient approach to amend the properties of biocatalyst required during wastewater treatment. The present study was done to immobilize partially purified ginger peroxidase on amino functionalized silica coated titanium dioxide nanocomposite. Interestingly there was an enhancement in enzyme activity after immobilization on nanosupport which was evident from effectiveness factor (η) value of 1.76. Immobilized enzyme was characterized by transmission electron microscopy, scanning electron microscopy and Fourier transform infrared spectroscopy. Immobilized peroxidase exhibited higher activity in a broad range of pH and temperature as compared to free enzyme. Also, the thermostability of peroxidase was strikingly improved upon immobilization. After six repeated uses, the immobilized peroxidase retained around 62% of its dye decolorization activity. There was a 4 fold increase in Vmax of immobilized peroxidase as compared to free enzyme. Circular dichroism spectroscopy demonstrated conformational changes in the secondary structure of enzyme, a possible reason for the enhanced enzyme activity after immobilization. Immobilized peroxidase was highly efficient in the removal of acid yellow 42 dye in a stirred batch process. Our study shows that this bio-remediating system has remarkable potential for treatment of aromatic pollutants present in wastewater.

Keywords: acid yellow 42, decolorization, ginger peroxidase, immobilization

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8 A Study of Body Weight and Type Traits Recorded on Hairy Goat in Punjab, Pakistan

Authors: A. Qayyum, G. Bilal, H. M. Waheed

Abstract:

The objectives of the study were to determine phenotypic variations in Hairy goats for quantitative and qualitative traits and to analyze the relationship between different body measurements and body weight in Hairy goats. Data were collected from the Barani Livestock Production Research Institute (BLPRI) at Kherimurat, Attock and potential farmers who were raising hairy goats in the Potohar region. Twelve (12) phenotypic parameters were measured on 99 adult Hairy goat (18 male and 81 female). Four qualitative and 8 quantitative traits were investigated. Qualitative traits were visually observed and expressed as percentages. Descriptive analysis was done on quantitative variables. All hairy goats had predominately black body coat color (72%), whereas white (11%) and brown (11%) body coat color were also observed. Both the pigmented (45.5%) and non-pigmented (54.5%) type of body skin were observed in the goat breed. Horns were present in the majority (91%) of animals. Most of the animals (83%) had straight facial head profiles. Analysis was performed in SAS On-Demand for Academics using PROC mixed model procedure. Overall means ± SD of body weight (BW), body length (BL), height at wither (HAW), ear length (EL), head length (HL), heart girth (HG), tail length (TL) and MC (muzzle circumference) were 41.44 ± 12.21 kg, 66.40 ± 7.87 cm, 75.17 ± 7.83 cm, 22.99 ± 6.75 cm, 15.07 ± 3.44 cm, 76.54 ± 8.80 cm, 18.28 ± 4.18 cm, and 26.24 ± 5.192 cm, respectively. Sex had a significant effect on BL and HG (P < 0.05), whereas BW, HAW, EL, HL, TL, and MC were not significantly affected (P > 0.05). The herd had a significant effect on BW, BL, HAW, HL, HG, and TL (P < 0.05) except EL and MC (P > 0.05). Hairy goats appear to have the potential for selection as mutton breeds in the Potohar region of Punjab. The findings of the present study would help in the characterization and conservation of hairy goats using genetic and genomic tools in the future.

Keywords: body weight, Hairy goat, type traits Punjab, Pakistan

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7 Assessing the Effects of Climate Change on Wheat Production, Ensuring Food Security and Loss Compensation under Crop Insurance Program in Punjab-Pakistan

Authors: Mirza Waseem Abbas, Abdul Qayyum, Muhammad Islam

Abstract:

Climate change has emerged as a significant threat to global food security, affecting crop production systems worldwide. This research paper aims to examine the specific impacts of climate change on wheat production in Pakistan, Punjab in particular, a country highly dependent on wheat as a staple food crop. Through a comprehensive review of scientific literature, field observations, and data analysis, this study assesses the key climatic factors influencing wheat cultivation and the subsequent implications for food security in the region. A comparison of two subsequent Wheat seasons in Punjab was examined through climatic conditions, area, yield, and production data. From the analysis, it is observed that despite a decrease in the area under cultivation in the Punjab during the Wheat 2023 season, the production and average yield increased due to favorable weather conditions. These uncertain climatic conditions have a direct impact on crop yields. Last year due to heat waves, Wheat crop in Punjab suffered a significant loss. Through crop insurance, Wheat growers were provided with yield loss protection keeping in view the devastating heat wave and floods last year. Under crop insurance by the Government of the Punjab, 534,587 Wheat growers were insured with a $1.6 million premium subsidy. However, due to better climatic conditions, no loss in the yield was recorded in the insured areas. Crop Insurance is one of the suitable options for policymakers to protect farmers against climatic losses in the future as well.

Keywords: climate change, crop insurance, heatwave, wheat yield punjab

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6 Biosafety Study of Genetically Modified CEMB Sugarcane on Animals for Glyphosate Tolerance

Authors: Aminah Salim, Idrees Ahmed Nasir, Abdul Qayyum Rao, Muhammad Ali, Muhammad Sohail Anjum, Ayesha Hameed, Bushra Tabassum, Anwar Khan, Arfan Ali, Mariyam Zameer, Tayyab Husnain

Abstract:

Risk assessment of transgenic herbicide tolerant sugarcane having CEMB codon optimized cp4EPSPS gene was done in present study. Fifteen days old chicks taken from K&Ns Company were randomly assorted into four groups with eight chicks in each group namely control chicken group fed with commercial diet, non-transgenic group fed with non-experimental sugarcane and transgenic group fed with transgenic sugarcane with minimum and maximum level. Body weights, biochemical analysis for Urea, alkaline phosphatase, alanine transferase, aspartate transferase, creatinine and bilirubin determination and histological examination of chicks fed with four types of feed was taken at fifteen days interval and no significant difference was observed in body weight biochemical and histological studies of all four groups. Protein isolated from the serum sample was analyzed through dipstick and SDS-PAGE, showing the absence of transgene protein in the serum sample of control and experimental groups. Moreover the amplification of cp4EPSPS gene with gene specific primers of DNA isolated from chicks blood and also from commercial diet was done to determine the presence and mobility of any nucleotide fragment of the transgene in/from feed and no amplification was obtained in feed as well as in blood extracted DNA of any group. Also no mRNA expression of cp4EPSPS gene was obtained in any tissue of four groups of chicks. From the results it is clear that there is no deleterious or harmful effect of the CEMB codon optimized transgenic cp4EPSPS sugarcane on the chicks health.

Keywords: chicks, cp4EPSPS, glyphosate, sugarcane

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5 Paraplegic Dimensions of Asymmetric Warfare: A Strategic Analysis for Resilience Policy Plan

Authors: Sehrish Qayyum

Abstract:

In this age of constant technology, asymmetrical warfare could not be won. Attuned psychometric study confirms that screaming sometimes is more productive than active retaliation against strong adversaries. Asymmetric warfare is a game of nerves and thoughts with least vigorous participation for large anticipated losses. It creates the condition of paraplegia with partial but permanent immobility, which effects the core warfare operations, being screams rather than active retaliation. When one’s own power is doubted, it gives power to one’s own doubt to ruin all planning either done with superlative cost-benefit analysis. Strategically calculated estimation of asymmetric warfare since the early WWI to WWII, WWII-to Cold War, and then to the current era in three chronological periods exposits that courage makes nations win the battle of warriors to battle of comrades. Asymmetric warfare has been most difficult to fight and survive due to unexpectedness and being lethal despite preparations. Thoughts before action may be the best-assumed strategy to mix Regional Security Complex Theory and OODA loop to develop the Paraplegic Resilience Policy Plan (PRPP) to win asymmetric warfare. PRPP may serve to control and halt the ongoing wave of terrorism, guerilla warfare, and insurgencies, etc. PRPP, along with a strategic work plan, is based on psychometric analysis to deal with any possible war condition and tactic to save millions of innocent lives such that lost in Christchurch New Zealand in 2019, November 2015 Paris attacks, and Berlin market attacks in 2016, etc. Getting tangled into self-imposed epistemic dilemmas results in regret that becomes the only option of performance. It is a descriptive psychometric analysis of war conditions with generic application of probability tests to find the best possible options and conditions to develop PRPP for any adverse condition possible so far. Innovation in technology begets innovation in planning and action-plan to serve as a rheostat approach to deal with asymmetric warfare.

Keywords: asymmetric warfare, psychometric analysis, PRPP, security

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4 Structural Stress of Hegemon’s Power Loss: A Pestle Analysis for Pacification and Security Policy Plan

Authors: Sehrish Qayyum

Abstract:

Active military power contention is shifting to economic and cyberwar to retain hegemony. Attuned Pestle analysis confirms that structural stress of hegemon’s power loss drives a containment approach towards caging actions. Ongoing diplomatic, asymmetric, proxy and direct wars are increasing stress hegemon’s power retention due to tangled military and economic alliances. It creates the condition of catalepsy with defective reflexive control which affects the core warfare operations. When one’s own power is doubted it gives power to one’s own doubt to ruin all planning either done with superlative cost-benefit analysis. Strategically calculated estimation of Hegemon’s power game since the early WWI to WWII, WWII-to Cold War and then to the current era in three chronological periods exposits that Thucydides’s trap became the reason for war broke out. Thirst for power is the demise of imagination and cooperation for better sense to prevail instead it drives ashes to dust. Pestle analysis is a wide array of evaluation from political and economic to legal dimensions of the state matters. It helps to develop the Pacification and Security Policy Plan (PSPP) to avoid hegemon’s structural stress of power loss in fact, in turn, creates an alliance with maximum amicable outputs. PSPP may serve to regulate and pause the hurricane of power clashes. PSPP along with a strategic work plan is based on Pestle analysis to deal with any conceivable war condition and approach for saving international peace. Getting tangled into self-imposed epistemic dilemmas results in regret that becomes the only option of performance. It is a generic application of probability tests to find the best possible options and conditions to develop PSPP for any adversity possible so far. Innovation in expertise begets innovation in planning and action-plan to serve as a rheostat approach to deal with any plausible power clash.

Keywords: alliance, hegemon, pestle analysis, pacification and security policy plan, security

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3 Media Coverage on Child Sexual Abuse in Developing Countries

Authors: Hayam Qayyum

Abstract:

Print and Broadcast media are considered to be the most powerful social change agents and effective medium that can revolutionize the deter society into the civilized, responsible, composed society. Beside all major roles, imperative role of media is to highlight the human rights’ violation issues in order to provide awareness and to prevent society from the social evils and injustice. So, by pointing out the odds, media can lessen the magnitude of happenings within the society. For centuries, the “Silent Crime” i.e. Child Sexual Abuse (CSA) is gulping down the developing countries. This study will explore that how the appropriate Print and Broadcast media coverage can eliminate Child Sexual Abuse from the society. The immense challenge faced by the journalists today; is the accurate and ethical reporting and appropriate coverage to disclose the facts and deliver right message on the right time to lessen the social evils in the developing countries, by not harming the prestige of the victim. In case of CSA most of the victims and their families are not in favour to expose their children to media due to family norms and respect in the society. Media should focus on in depth information of CSA and use this coverage is to draw attention of the concern authorities to look into the matter for reforms and reviews in the system. Moreover, media as a change agent can bring such issue into the knowledge of the international community to make collective efforts with the affected country to eliminate the ‘Silent Crime’ from the society. The model country selected for this research paper is South Africa. The purpose of this research is not only to examine the existing reporting patterns and content of print and broadcast media coverage of South Africa but also aims to create awareness to eliminate Child Sexual abuse and indirectly to improve the condition of stake holders to overcome this social evil. The literature review method is used to formulate this paper. Trends of media content on CSA will be identified that how much amount and nature of information made available to the public through the media General view of media coverage on child sexual abuse in developing countries like India and Pakistan will also be focused. This research will be limited to the role of print and broadcast media coverage to eliminate child sexual abuse in South Africa. In developing countries, CSA issue needs to be addressed on immediate basis. The study will explore the CSA content of the most influential broadcast and print media outlets of South Africa. Broadcast media will be comprised of TV channels and print media will be comprised of influential newspapers. South Africa is selected as a model for this research paper.

Keywords: child sexual abuse, developing countries, print and broadcast media, South Africa

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2 The Study of Mirror Self-Recognition in Wildlife

Authors: Azwan Hamdan, Mohd Qayyum Ab Latip, Hasliza Abu Hassim, Tengku Rinalfi Putra Tengku Azizan, Hafandi Ahmad

Abstract:

Animal cognition provides some evidence for self-recognition, which is described as the ability to recognize oneself as an individual separate from the environment and other individuals. The mirror self-recognition (MSR) or mark test is a behavioral technique to determine whether an animal have the ability of self-recognition or self-awareness in front of the mirror. It also describes the capability for an animal to be aware of and make judgments about its new environment. Thus, the objectives of this study are to measure and to compare the ability of wild and captive wildlife in mirror self-recognition. Wild animals from the Royal Belum Rainforest Malaysia were identified based on the animal trails and salt lick grounds. Acrylic mirrors with wood frame (200 x 250cm) were located near to animal trails. Camera traps (Bushnell, UK) with motion-detection infrared sensor are placed near the animal trails or hiding spot. For captive wildlife, animals such as Malayan sun bear (Helarctos malayanus) and chimpanzee (Pan troglodytes) were selected from Zoo Negara Malaysia. The captive animals were also marked using odorless and non-toxic white paint on its forehead. An acrylic mirror with wood frame (200 x 250cm) and a video camera were placed near the cage. The behavioral data were analyzed using ethogram and classified through four stages of MSR; social responses, physical inspection, repetitive mirror-testing behavior and realization of seeing themselves. Results showed that wild animals such as barking deer (Muntiacus muntjak) and long-tailed macaque (Macaca fascicularis) increased their physical inspection (e.g inspecting the reflected image) and repetitive mirror-testing behavior (e.g rhythmic head and leg movement). This would suggest that the ability to use a mirror is most likely related to learning process and cognitive evolution in wild animals. However, the sun bear’s behaviors were inconsistent and did not clearly undergo four stages of MSR. This result suggests that when keeping Malayan sun bear in captivity, it may promote communication and familiarity between conspecific. Interestingly, chimp has positive social response (e.g manipulating lips) and physical inspection (e.g using hand to inspect part of the face) when they facing a mirror. However, both animals did not show any sign towards the mark due to lost of interest in the mark and realization that the mark is inconsequential. Overall, the results suggest that the capacity for MSR is the beginning of a developmental process of self-awareness and mental state attribution. In addition, our findings show that self-recognition may be based on different complex neurological and level of encephalization in animals. Thus, research on self-recognition in animals will have profound implications in understanding the cognitive ability of an animal as an effort to help animals, such as enhanced management, design of captive individuals’ enclosures and exhibits, and in programs to re-establish populations of endangered or threatened species.

Keywords: mirror self-recognition (MSR), self-recognition, self-awareness, wildlife

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1 Sonication as a Versatile Tool for Photocatalysts’ Synthesis and Intensification of Flow Photocatalytic Processes Within the Lignocellulose Valorization Concept

Authors: J. C. Colmenares, M. Paszkiewicz-Gawron, D. Lomot, S. R. Pradhan, A. Qayyum

Abstract:

This work is a report of recent selected experiments of photocatalysis intensification using flow microphotoreactors (fabricated by an ultrasound-based technique) for photocatalytic selective oxidation of benzyl alcohol (BnOH) to benzaldehyde (PhCHO) (in the frame of the concept of lignin valorization), and the proof of concept of intensifying a flow selective photocatalytic oxidation process by acoustic cavitation. The synthesized photocatalysts were characterized by using different techniques such as UV-Vis diffuse reflectance spectroscopy, X-ray diffraction, nitrogen sorption, thermal gravimetric analysis, and transmission electron microscopy. More specifically, the work will be on: a Design and development of metal-containing TiO₂ coated microflow reactor for photocatalytic partial oxidation of benzyl alcohol: The current work introduces an efficient ultrasound-based metal (Fe, Cu, Co)-containing TiO₂ deposition on the inner walls of a perfluoroalkoxy alkanes (PFA) microtube under mild conditions. The experiments were carried out using commercial TiO₂ and sol-gel synthesized TiO₂. The rough surface formed during sonication is the site for the deposition of these nanoparticles in the inner walls of the microtube. The photocatalytic activities of these semiconductor coated fluoropolymer based microreactors were evaluated for the selective oxidation of BnOH to PhCHO in the liquid flow phase. The analysis of the results showed that various features/parameters are crucial, and by tuning them, it is feasible to improve the conversion of benzyl alcohol and benzaldehyde selectivity. Among all the metal-containing TiO₂ samples, the 0.5 at% Fe/TiO₂ (both, iron and titanium, as cheap, safe, and abundant metals) photocatalyst exhibited the highest BnOH conversion under visible light (515 nm) in a microflow system. This could be explained by the higher crystallite size, high porosity, and flake-like morphology. b. Designing/fabricating photocatalysts by a sonochemical approach and testing them in the appropriate flow sonophotoreactor towards sustainable selective oxidation of key organic model compounds of lignin: Ultrasonication (US)-assitedprecipitaion and US-assitedhydrosolvothermal methods were used for the synthesis of metal-oxide-based and metal-free-carbon-based photocatalysts, respectively. Additionally, we report selected experiments of intensification of a flow photocatalytic selective oxidation through the use of ultrasonic waves. The effort of our research is focused on the utilization of flow sonophotocatalysis for the selective transformation of lignin-based model molecules by nanostructured metal oxides (e.g., TiO₂), and metal-free carbocatalysts. A plethora of parameters that affects the acoustic cavitation phenomena, and as a result the potential of sonication were investigated (e.g. ultrasound frequency and power). Various important photocatalytic parameters such as the wavelength and intensity of the irradiated light, photocatalyst loading, type of solvent, mixture of solvents, and solution pH were also optimized.

Keywords: heterogeneous photo-catalysis, metal-free carbonaceous materials, selective redox flow sonophotocatalysis, titanium dioxide

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