Graduate Student Papers

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Optimizing Schools: An Ethical Analysis of AI Integration in Education
Aina, Adeyemi (2025-01-03)
This case highlights the intersection of technology, society, and ethics, where AI offers transformative opportunities to identify struggling students and enhance their well-being through tailored interventions. However, it also presents risks, including algorithmic bias, data misuse, and a shift away from human-centered education. The Minerva High School case underscores broader ethical challenges in integrating AI into public institutions, particularly those serving vulnerable populations, prompting critical questions about balancing innovation with respect for individual rights and whether technological efficiency should outweigh traditional educational values. This analysis explores these dilemmas through ethical frameworks, offering insights into the responsible deployment of technology in society.
Public health insurance coverage in India before and after PM-JAY: Repeated cross-sectional analysis of nationally representative survey data
Mohanty, Sanjay K.; Upadhyay, Ashish Kumar; Maiti, Suraj; Mishra, Radhe Shyam; Kämpfen, Fabrice; Maurer, Jürgen; O'Donnell, Owen (BMJ, 2023-08-28)
Introduction The provision of non-contributory public health insurance (NPHI) to marginalised populations is a critical step along the path to universal health coverage. We aimed to assess the extent to which Ayushman Bharat-Pradhan Mantri Jan Arogya Yojana (PM-JAY) - potentially, the world's largest NPHI programme - has succeeded in raising health insurance coverage of the poorest two-fifths of the population of India. Methods We used nationally representative data from the National Family Health Survey on 633 699 and 601 509 households in 2015-2016 (pre-PM-JAY) and 2019-2021 (mostly, post PM-JAY), respectively. We stratified by urban/rural and estimated NPHI coverage nationally, and by state, district and socioeconomic categories. We decomposed coverage variance between states, districts, and households and measured socioeconomic inequality in coverage. For Uttar Pradesh, we tested whether coverage increased most in districts where PM-JAY had been implemented before the second survey and whether coverage increased most for targeted poorer households in these districts. Results We estimated that NPHI coverage increased by 11.7 percentage points (pp) (95% CI 11.0% to 12.4%) and 8.0 pp (95% CI 7.3% to 8.7%) in rural and urban India, respectively. In rural areas, coverage increased most for targeted households and pro-rich inequality decreased. Geographical inequalities in coverage narrowed. Coverage did not increase more in states that implemented PM-JAY. In Uttar Pradesh, the coverage increase was larger by 3.4 pp (95% CI 0.9% to 6.0%) and 4.2 pp (95% CI 1.2% to 7.1%) in rural and urban areas, respectively, in districts exposed to PM-JAY and the increase was 3.5 pp (95% CI 0.9% to 6.1%) larger for targeted households in these districts. Conclusion The introduction of PM-JAY coincided with increased public health insurance coverage and decreased inequality in coverage. But the gains cannot all be plausibly attributed to PM-JAY, and they are insufficient to reach the goal of universal coverage of the poor.
Healthcare inequity arising from unequal response to need in the older (45+ years) population of India: Analysis of nationally representative data
Mohanty, Sanjay K.; Khan, Junaid; Maiti, Suraj; Kämpfen, Fabrice; Maurer, Jürgen; O'Donnell, Owen (Elsevier, 2024-11-20)
Given the large and growing number of older (45+ years) people in India, inequitable access to healthcare in this population would slow global progress toward universal health coverage. We used a 2017-18 nationally representative sample of this population (n = 53,687) to estimate healthcare inequality and inequity by economic status. We used an extensive battery of indicators in nine health domains, plus age and sex, to adjust for need. We measured economic status by monthly per capita consumption expenditure and used a concentration index to measure inequalities in probabilities of any doctor visit and any hospitalisation within 12 months. We decomposed inequality with a regression method that allowed for economic and urban/rural heterogeneity in partial associations between healthcare and both need and non-need covariates. We used the associations achieved by the richest fifth of urban dwellers to predict a need-justified distribution of healthcare and compared the actual distribution with that benchmark to identify inequity. We found pro-rich inequalities in doctor visits and hospitalisations, which were driven by use of private healthcare. Adjustment for the greater need of poorer individuals revealed pro-rich inequity that exceeded inequality by about 65% and 39% for doctor visits and hospitalisations, respectively. These adjustments would have been substantially smaller, and inequity underestimated, without allowing for use-need heterogeneity, which accounted for 11% of the inequity in doctor visits and was 373% of inequity in hospitalisations. Targeting service coverage on poorer and rural groups, and increasing their access to private providers, would both reduce inequity and raise average coverage in the older population of India.
Out-of-pocket payment and financial risk protection for breast cancer treatment: a prospective study from India
Wadasadawala, Tabassum; Mohanty, Sanjay K.; Sen, Soumendu; Kanala, Tejaswi S.; Maiti, Suraj; Puchali, Namita; Gupta, Sudeep; Sarin, Rajiv; Parmar, Vani (Elsevier, 2024-01-16)
Background: Available data on cost of cancer treatment, out-of-pocket payment and reimbursement are limited in India. We estimated the treatment costs, out-of-pocket payment, and reimbursement in a cohort of breast cancer patients who sought treatment at a publicly funded tertiary cancer care hospital in India. Methods: A prospective longitudinal study was conducted from June 2019 to March 2022 at Tata Memorial Centre (TMC), Mumbai. Data on expenditure during each visit of treatment was collected by a team of trained medical social workers. The primary outcome variables were total cost (TC) of treatment, out-of-pocket payment (OOP), and reimbursement. TC included cost incurred by breast cancer patients during treatment at TMC. OOP was defined as the total cost incurred at TMC less of reimbursement. Reimbursement was any form of financial assistance (cashless or repayment), including social health insurance, private health insurance, employee health schemes, and assistance from charitable trusts, received by the patients for breast cancer treatment. Findings: Of the 500 patients included in the study, 45 discontinued treatment (due to financial or other reasons) and 26 died during treatment. The mean TC of breast cancer treatment was ₹258,095/US$3531 (95% CI: 238,225, 277,934). Direct medical cost (MC) accounted for 56.3% of the TC. Systemic therapy costs (₹50,869/US$696) were higher than radiotherapy (₹33,483/US$458) and surgery costs (₹25,075/US$343). About 74.4% patients availed some form of financial assistance at TMC; 8% patients received full reimbursement. The mean OOP for breast cancer treatment was ₹186,461/US$2551 (95% CI: 167,666, 205,257), accounting for 72.2% of the TC. Social health insurance (SHI) had a reasonable coverage (33.1%), followed by charitable trusts (29.6%), employee health insurance (5.1%), private health insurance (4.4%) and 25.6% had no reimbursement. But SHI covered only 40.1% of the TC of treatment compared to private health insurance that covered as much as 57.1% of it. Both TC and OOP were higher for patients who were younger, belonged to rural areas, had a comorbidity, were diagnosed at an advanced stage, and were from outside Maharashtra. Interpretation: In India, the cost and OOP for breast cancer treatment are high and reimbursement for the treatment flows from multiple sources. Though many of the patients receive some form of reimbursement, it is insufficient to prevent high OOP. Hence both wider insurance coverage as well as higher cap of the insurance packages in the health insurance schemes is suggested. Allowing for the automatic inclusion of cancer treatment in SHI can mitigate the financial burden of cancer patients in India. Funding: This work was funded by an extramural grant from the Women's Cancer Initiative and the Nag Foundation and an intramural grant from the International Institute of Population Sciences, Mumbai.
Catastrophic health expenditure and distress financing of breast cancer treatment in India: evidence from a longitudinal cohort study
Mohanty, Sanjay K.; Wadasadawala, Tabassum; Sen, Soumendu; Maiti, Suraj; E, Jishna (Springer, 2024-07-23)
Objective: To estimate the catastrophic health expenditure and distress financing of breast cancer treatment in India. Methods: The unit data from a longitudinal survey that followed 500 breast cancer patients treated at Tata Memorial Centre (TMC), Mumbai from June 2019 to March 2022 were used. The catastrophic health expenditure (CHE) was estimated using households' capacity to pay and distress financing as selling assets or borrowing loans to meet cost of treatment. Bivariate and logistic regression models were used for analysis. Findings: The CHE of breast cancer was estimated at 84.2% (95% CI: 80.8,87.9%) and distress financing at 72.4% (95% CI: 67.8,76.6%). Higher prevalence of CHE and distress financing was found among rural, poor, agriculture dependent households and among patients from outside of Maharashtra. About 75% of breast cancer patients had some form of reimbursement but it reduced the incidence of catastrophic health expenditure by only 14%. Nearly 80% of the patients utilised multiple financing sources to meet the cost of treatment. The significant predictors of distress financing were catastrophic health expenditure, type of patient, educational attainment, main income source, health insurance, and state of residence. Conclusion: In India, the CHE and distress financing of breast cancer treatment is very high. Most of the patients who had CHE were more likely to incur distress financing. Inclusion of direct non-medical cost such as accommodation, food and travel of patients and accompanying person in the ambit of reimbursement of breast cancer treatment can reduce the CHE. We suggest that city specific cancer care centre need to be strengthened under the aegis of PM-JAY to cater quality cancer care in their own states of residence.
Compressive and Flexural Strength Characteristics of Paving Stones Produced with Concrete Modified with Polypropylene Waste Chair
Olukanni, E. O.; Oyedepo, O. J.; Arowolo, T. R. (Proceedings of the 2021 Annual Conference of the School of Engineering & Engineering Technology, FUTA, 6th – 8th October, 2021, 2021-10)
The demand for a better performing pavement and the need to convert the ever-growing polymer waste into beneficial use necessitated the need to develop and characterize a polypropylene modified concrete for use in pavement construction. This research focuses on characterizing the strength of concrete produced with polypropylene waste as modifiers for pavement construction. The materials used in this research are fine and coarse aggregates, cement and polypropylene waste chairs (PWC). Tests were performed on the aggregate and fresh concrete to determine their suitability and characteristics for use in concrete for pavement. Two concrete grades 1:2:4 and 1:3:6 was produced into 200 mm, 400 mm and 500 mm long paving stones on which compressive and flexural tests were performed. Results obtained showed that 400 mm 1:2:4 grade concrete has the highest compressive strength of 27.36 N/mm2 at 10% polypropylene composition. The 200 mm 1:2:4 concrete grade paving stone with 10% polyprpopylene composition has the highest flexural strength of 12.90 N/mm2 . It was concluded that the 200 mm long 1:2:4 concrete grade paving stone at 10% polypropylene composition is the best length of paving stone that can give an adequate flexural strength which is the most important requirent in concrete pavement requirement.
Evaluation of Rheological Characteristics of Graphite Modified Bitumen
Oladunjoye, O. O.; Oyedepo, O. J.; Olukanni, E. O.; Akande, S. P. (Proceedings of the 2021 Annual Conference of the School of Engineering & Engineering Technology, FUTA, 6th – 8th October, 2021, 2021-03-06)
The level of performance of asphalt concrete has a close relationship with the properties of bitumen used. This research evaluates the rheological parameters of graphite modified bitumen. Index properties tests were conducted on bitumen and graphite to determine their suitability. Dynamic viscosity and dynamic shear rheometer were conducted on bituminous binder modified with four different proportion of graphite ranging from 2% to 10% by bitumen weight. Dynamic viscosity test was conducted on bitumen and graphite modified bitumen at temperature of 1350C and 1650C using Brookfield Viscometer. The rheological properties are centered on phase angle (δ) and complex shear modulus (G*) which were determined on bitumen and graphite modified bitumen at temperature ranging from 520C – 700C at 10 rad/s frequency using Dynamic Shear Rheometer in accordance with ASTM D7175-15. The storage modulus (G ' ), loss modulus (G") and rutting parameters were then evaluated from phase angle and complex shear modulus. The bitumen and graphite modified bitumen showed that graphite modified bitumen has the highest complex shear modulus and rutting parameter of 8984 (kPa) and 33387 (kPa) at 10% graphite content. The results of viscosity helped to determine the mixing and compaction temperatures. Dynamic shear rheometer test results determined the elastic and viscous behaviour at various temperature. The higher the complex shear modulus and rutting parameter the stiffer the binder will resist deformation and rutting.
Global Perspectives Program 2024 Final Report
Dosumu, Fiyinfunjah Adenike (2024)
Implementation and Evaluation of GBDI Memory Compression Algorithm Using C/C++ on a Broader Range of Workloads
Aina, Adeyemi (2023-05-03)
Memory compression is an important approach in computer architecture for decreasing memory footprint and improving system performance. In this paper, we use C/C++ to develop a current memory compression algorithm; the Global Bases Delta Immediate (GBDI) algorithm, which was proposed at HPCA'2022. By using global bases and enabling deltas within the same block to vary in size, the GBDI compression algorithm decreases the size of encoded data. The goal of this research is to assess the effectiveness of the GBDI algorithm by examining its compression ratios under a broader range of workloads. Our research leads to a better knowledge of the GBDI algorithm's effectiveness and the potential benefits of memory compression techniques for various sorts of applications. Furthermore, our C/C++ version of the algorithm gives academics and practitioners a high degree of freedom over customizing the algorithm for individual workloads and optimizing its performance.
How the Climate Change Threat is Shifting Australia's National Counter-Terrorism Strategy
Mortazavigazar, Amir (2023-03-08)
In this paper, we analyse how extremism and acts of terror will manifest themselves in Australia over the upcoming decades. Australia maintains a robust counter-terrorism strategy along with a comprehensive security apparatus to support that strategy. However, it is becoming apparent to the Australian intelligence community and the Australian government that the national security challenges that Australia will be facing due to climate change have been neglected over the past few years. COVID-19 restrictions demonstrated that issue-motivated extremism can fuel acts of terror and assist violent extremist organisations in their recruitment and radicalisations. In this paper, we demonstrate how climate change mitigation policies can result in issue-motivated extremism and empower violent extremist organisations which can result in acts of terror that would jeopardise Australia’s national security, therefore, we recommend that Australia’s National Intelligence apparatus broaden the issue-motivated extremism purview of terrorism by including climate change related grievances. Furthermore, we recommend amending Australia’s social cohesion and value statements to alleviate climate change related grievances and raise awareness about the threats of climate change related extremism.
Integrating health, economic, and environmental trade-offs into decarbonization decision-making in New England
Mortazavigazar, Amir (2024-05-15)
Emerging nuclear energy technologies: An alternative path to Australia's energy security
Mortazavigazar, Amir (Menzies Research Centre, 2023-12-18)
Gender Differences in Farmers' Indigenous Knowledge of Vegetables Disease Management: Implication for Artificial Intelligence-Enabled Farmers' Decision Support System
Deji, Olanike; Adisa, Priscilla; Ogunbona, Philip; Faniyi, Ebunoluwa; Olowoyo, Olamide; Jubril, Abimbola; Omotola, Olajide; Olukayode, Samuel (Rural Sociological Association of Nigeria, 2021)
The study was carried out in Osun State, Nigeria with the aim to analyse male and female vegetable farmers’ indigenous knowledge of disease management. It specifically assessed the indigenous knowledge of male and female farmers on the symptoms, causes, curative, and preventive measures of the vegetable crop diseases. This was done with the aim to provide gender-responsive benchmark data that could enhance the effective adoption of AI-enabled decision support system for crop disease management. Structured interview schedule was used to elicit quantitative data from 106 respondents (59 males and 47 females) for the study. Descriptive statistics was used to analyse the data. Majority of the male and female farmers used indigenous knowledge in identifying the symptoms, causes, curative and preventive measures of most common vegetable crop diseases. Expert/Extension professional-based human intelligence was also a major source of information on crop disease management among the male and female farmers, but the female farmers experienced lower extension contacts than the males. Scientific study and integration of gender responsive and enabling indigenous knowledge on crop disease management into the AI-enabled farmers’ decision support system involving experts and extension professionals is recommended for effectiveness and sustainability
A Camelid-Derived STAT-Specific Nanobody Inhibits Neuroinflammation and Ameliorates Experimental Autoimmune Encephalomyelitis (EAE)
Mbanefo, Evaristus C.; Seifert, Allison; Yadav, Manoj Kumar; Yu, Cheng-Rong; Nagarajan, Vijayaraj; Parihar, Ashutosh; Singh, Sunanda; Egwuagu, Charles E. (MDPI, 2024-06-16)
Proinflammatory T-lymphocytes recruited into the brain and spinal cord mediate multiple sclerosis (MS) and currently there is no cure for MS. IFN-γ-producing Th1 cells induce ascending paralysis in the spinal cord while IL-17-producing Th17 cells mediate cerebellar ataxia. STAT1 and STAT3 are required for Th1 and Th17 development, respectively, and the simultaneous targeting of STAT1 and STAT3 pathways is therefore a potential therapeutic strategy for suppressing disease in the spinal cord and brain. However, the pharmacological targeting of STAT1 and STAT3 presents significant challenges because of their intracellular localization. We have developed a STAT-specific single-domain nanobody (SBT-100) derived from camelids that targets conserved residues in Src homolog 2 (SH2) domains of STAT1 and STAT3. This study investigated whether SBT-100 could suppress experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. We show that SBT-100 ameliorates encephalomyelitis through suppressing the expansion of Th17 and Th1 cells in the brain and spinal cord. Adoptive transfer experiments revealed that lymphocytes from SBT-100-treated EAE mice have reduced capacity to induce EAE, indicating that the immunosuppressive effects derived from the direct suppression of encephalitogenic T-cells. The small size of SBT-100 makes this STAT-specific nanobody a promising immunotherapy for CNS autoimmune diseases, including multiple sclerosis.
Construction Supply Chain Management Practice and Impact on Project Performance: Perspective From Nigerian Construction Firms
Adegoke, Abiola; Dada, Joshua (Nigerian Institute of Quantity Surveyors, 2022-10-27)
This paper investigates the awareness and extent of construction supply chain management (CSCM) practice by construction firms in Nigeria. In addition, the impact of CSCM on project cost and time performance was evaluated. Design/methodology/approach – A well structure questionnaire survey was administered on the ninety-two construction firms registered with the Bureau of Public Procurement of Oyo State in Southwestern Geopolitical Zone of Nigeria. Descriptive and inferential statistics were used to analyse the elicited data. The results show that construction firms in Nigeria are generally aware of CSCM. While the experience of small, medium and large-scale construction firms on CSCM practice differs, information acquisition and sharing (among other ten significant variables) was found to be the most important element. In determining the impact of CSCM practice on project cost, the eleven identified significant elements were used to develop a multi linear regression model equation Y = 3.654-0.053X1 – 0.036X2 – 0.041X3 - 0.065X4- 0.024X5 - 0.013 X6 - 0.021 X7- 0.021X8- 0.013 X9 - 0.035 X10 - 0.011X11. (Where Y is the cost of construction project and X1…X11 are elements of CSCM practice). In the same vein a model equation showing the impact of CSCM practice on project duration was developed as Y = 5.189-0.022X1 – 0.014X2 – 0.034X3 - 0.025X4- 0.060X5 - 0.011X6 - 0.036 X7 - 0.016X8 - 0.034 X9 - 0.014 X10 - 0.023X11. The generated model equations show an inverse relationship between cost and duration of construction projects and elements of CSCM practice. This implies that adequate utilisation of the elements of CSCM practice will lead to an appreciable reduction in project cost and time. Apart from the general impact of CSCM practice; the quantum effect of each of the elements can be evaluated from the model equations.
Gender Analysis of Factors Influencing Soil and Water Conservation Technology Utilization among Vegetable Farmers in Ekiti and Oyo States, Nigeria
Faniyi, Ebunoluwa; Deji, Olanike; Olowoyo, Olamide; Sulaimon, Waheed; Aduwo, Oluwafunke (Nigerian Journal of Rural Sociology, 2019)
The study assessed the gender analysis of factors associated with soil and water conservation technology usage among vegetable farmers in Ekiti and Oyo States, Nigeria. It specifically, described the socioeconomic characteristics of vegetable farmers and examined the gender-specific factors associated with soil and water conservation technology utilisation in vegetable production. The study adopted a multi-stage sampling procedure. Data were elicited from the respondents using an interview schedule and focus group discussion guide. The study used inferential and descriptive statistics to analyse the data from the survey. The findings showed that the mean age for male was 35 years and female vegetable farmers 41 years. While the mean years of vegetable farming experience for male was 16 years and female vegetable farmers was 19 years. Varimax factor rotation pattern was used to isolate six factors associated with soil and water conservation technology usage for male vegetable farmers, which were information-source factor (14.4%), family factor (14.0%), resources factor (11.7%), economic factor (10.5%), soil-fertility factor (8.3%), and institutional factor (8.0%). Also,five factors were isolated for the female vegetable which were include; personal-experience factor (21.6%), information source factor (20.0%), land acquisition factor (10.7%), resources factor (10.0%), and group membership factor (7.7%). Information, resources, economic, personal experience, and land acquisition were the gender-specific factors influencing soil water conservation (SWC) technology usage. It was recommended that the factors identified should be noted as springboard for technology development and dissemination in Nigeria, this will help in the removal of the existing gender gaps among the farmers, especially in the rural areas and ensure sustainable agricultural practices and rural transformation.
Effects of the Phosphodiesterase 10A Inhibitor MR1916 on Alcohol Self-Administration and Striatal Gene Expression in Post-Chronic Intermittent Ethanol-Exposed Rats
Bertotto, Luísa B.; Lampson-Stixrud, Dolly; Sinha, Anushka; Rohani, Nicki K.; Myer, Isabella; Zorrilla, Eric P. (MDPI, 2024-02-09)
Alcohol use disorder (AUD) requires new neurobiological targets. Problematic drinking involves underactive indirect pathway medium spiny neurons (iMSNs) that subserve adaptive behavioral selection vs. overactive direct pathway MSNs (dMSNs) that promote drinking, with a shift from ventromedial to dorsolateral striatal (VMS, DLS) control of EtOH-related behavior. We hypothesized that inhibiting phosphodiesterase 10A (PDE10A), enriched in striatal MSNs, would reduce EtOH self-administration in rats with a history of chronic intermittent ethanol exposure. To test this, Wistar rats (n = 10/sex) with a history of chronic intermittent EtOH (CIE) vapor exposure received MR1916 (i.p., 0, 0.05, 0.1, 0.2, and 0.4 µmol/kg), a PDE10A inhibitor, before operant EtOH self-administration sessions. We determined whether MR1916 altered the expression of MSN markers (Pde10a, Drd1, Drd2, Penk, and Tac1) and immediate-early genes (IEG) (Fos, Fosb, ΔFosb, and Egr1) in EtOH-naïve (n = 5–6/grp) and post-CIE (n = 6–8/grp) rats. MR1916 reduced the EtOH self-administration of high-drinking, post-CIE males, but increased it at a low, but not higher, doses, in females and low-drinking males. MR1916 increased Egr1, Fos, and FosB in the DLS, modulated by sex and alcohol history. MR1916 elicited dMSN vs. iMSN markers differently in ethanol-naïve vs. post-CIE rats. High-drinking, post-CIE males showed higher DLS Drd1 and VMS IEG expression. Our results implicate a role and potential striatal bases of PDE10A inhibitors to influence post-dependent drinking.
Psychosocial Factors Associated with Lower Urinary Tract Symptoms One Year Postpartum
Cunningham, Shayna D.; Carandang, Rogie Royce; Boyd, Lisa M.; Lewis, Jessica B.; Ickovics, Jeannette R.; Rickey, Leslie M. (MDPI, 2023-12-27)
Pregnancy carries substantial risk for developing lower urinary tract symptoms (LUTSs), with potential lifelong impacts on bladder health. Little is known about modifiable psychosocial factors that may influence the risk of postpartum LUTSs. We examined associations between depressive symptoms, perceived stress, and postpartum LUTSs, and the moderating effects of perceived social support, using data from a cohort study of Expect With Me group prenatal care (n = 462). One year postpartum, 40.3% participants reported one or more LUTS. The most frequent LUTS was daytime frequency (22.3%), followed by urinary incontinence (19.5%), urgency (18.0%), nocturia (15.6%), and bladder pain (6.9%). Higher odds of any LUTS were associated with greater depressive symptoms (adjusted odds ratio (AOR) 1.08, 95% confidence interval (CI) 1.04–1.11) and perceived stress (AOR 1.12, 95% CI 1.04–1.19). Higher perceived social support was associated with lower odds of any LUTS (AOR 0.94, 95% CI 0.88–0.99). Perceived social support mitigated the adverse effects of depressive symptoms (interaction AOR 0.99, 95% CI 0.98–0.99) and perceived stress (interaction AOR 0.97, 95% CI 0.95–0.99) on experiencing any LUTS. Greater depressive symptoms and perceived stress may increase the likelihood of experiencing LUTSs after childbirth. Efforts to promote bladder health among postpartum patients should consider psychological factors and social support.
Effects of Activation Barriers on Quenching to Stabilize Prebiotic Chemical Systems
Sheng, Qianyi; Intoy, Ben Fredrick; Halley, J. W. (MDPI, 2024-01-12)
We have previously shown in model studies that rapid quenches of systems of monomers interacting to form polymer chains can fix nonequilibrium chemistries with some lifelike properties. We suggested that such quenching processes might have occurred at very high rates on early Earth, giving an efficient mechanism for natural sorting through enormous numbers of nonequilibrium chemistries from which the most lifelike ones could be naturally selected. However, the model used for these studies did not take account of activation barriers to polymer scission (peptide bond hydrolysis in the case of proteins). Such barriers are known to exist and are expected to enhance the quenching effect. Here, we introduce a modified model which takes activation barriers into account and we compare the results to data from experiments on quenched systems of amino acids. We find that the model results turn out to be sensitive to the width of the distribution of barrier heights but quite insensitive to its average value. The results of the new model are in significantly better agreement with the experiments than those found using our previous model. The new parametrization of the model only requires one new parameter and the parametrization is more physical than the previous one, providing a chemical interpretation of the parameter p in our previous models. Within the model, a characteristic temperature Tc emerges such that if the temperature of the hot stage is above Tc and the temperature of the cold stage is below it, then the ‘freezing out’, in a quench, of a disequilibrium ensemble of long polymers is expected. We discuss the possible relevance of this to models of the origin of life in emissions from deep ocean rifts.
Gender Specific Factors Associated With Hazards of Pesticide Usage among Cocoa Farmers in Nigeria
Olowoyo, Olamide; Deji, Olanike Fasilat; Sulaimon, Waheed Suberu; Faniyi, Ebunoluwa Oyindamola (2019)
This study assessed the gender specific factors associated with health and environmental hazards of pesticide usage among cocoa farmers in Ekiti State, Nigeria a region known with predominance in cocoa production. It specifically described the socio-economic characteristics of male and female cocoa farmers and isolate factors associated with health and environmental hazards of pesticide usage in cocoa production. 120 male cocoa farmers and 120 female cocoa farmers were selected through multi stage purposive sampling technique in five local government areas of the state, to make a total of 240 respondents for the study. The study adopts the use of inferential and descriptive statistics to analyze the data from the survey. The mean age for male and female cocoa farmers was 52.5±9.82 and 45.2± 8.49 respectively while the mean years of cocoa farming experience for male and female cocoa farmers was 27.9±9.23 and 22.3±9.68 respectively. Varimax factor rotation pattern was used to isolate six factors associated with health and environmental hazards for male cocoa farmers which include: ‘information source factor’, ‘extension contact factor’, ‘experience factor’, ‘knowledge-pesticide usage factor’, ‘group membership factor’ and ‘family factor’ and six factors associated with health and environmental hazards for female cocoa farmers which include: ‘knowledge factor’, ‘information source factor’ ‘group membership factor’ ‘extension contact factor’ ‘family factor’ and ‘pesticide usage’ were isolated. Awareness of the gender specific factors to understanding hidden gender issues associated with hazards of pesticide usage among cocoa farmers was recommended. Hence, this is to ensure sustainable pesticide usage and to boost environmental productivity for rural development.

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