National University (California)
  • San Diego, CA, United States
Recent publications
Biological control based on entomopathogenic fungi is a promising option for controlling ticks on livestock. The objective of this study was to evaluate acaricidal effect of M. anisopliae (Metschnikoff) Sorokin (Ma14 strain) against R. microplus (Canestrini, 1887) on cattle. Thirty heifers naturally infested with R. microplus were divided into three groups of 10 each. One group was sprayed with Ma14 strain at a concentration of 108 conidia/ml and 0.1% Tween 80, the second was sprayed with M. anisopliae Ma34 strain at the same concentration and considered a positive check. The third group remained a nontreated check. Efficacy of Ma14 was 38.3 to 51.3% from the fourth application to the end of the experiment. The Ma14 strain had considerable efficacy against naturally infesting ticks, which makes it a candidate for use in integrated tick management.
Diet-related fiscal policy is an effective NCD prevention strategy. However, current sugar-sweetened beverage (SSB) taxes in Fiji and Tonga have not had the desired effect; SSB consumption in Fiji, for example, contributes to mortality more than double the global rates and is highest in the WHO Western Pacific Region. We therefore aimed to better understand the perceived underlying political economy drivers that have and continue to affect change in each country. Our study design utilised a comparative case study that triangulated documentary policy and stakeholder analysis with semi-structured stakeholder interviews in both countries and an in-depth corporate political activity analysis in Fiji. We drew on theoretical frameworks relevant to political economy to collect and analyse policy and stakeholder data, and utilised established corporate political activity frameworks to analyse industry activity. Common findings to both Fiji and Tonga suggested that the SSB tax impact could be increased through multisectoral engagement, embracing a whole-of-society approach, strengthened institutional structures and leveraging off competing priorities across sectors towards more common goals. These findings provide opportunities and lessons for Fiji and Tonga as well as other similar settings seeking to strengthen or upscale the impact of diet-related fiscal policy.
Background There is a crisis of non-communicable diseases (NCDs) in the Pacific Islands, and poor diets are a major contributor. The COVID-19 pandemic and resulting economic crisis will likely further exacerbate the burden on food systems. Pacific Island leaders have adopted a range of food policies and regulations to improve diets. This includes taxes and regulations on compositional standards for salt and sugar in foods or school food policies. Despite increasing evidence for the effectiveness of such policies globally, there is a lack of local context-specific evidence about how to implement them effectively in the Pacific. Methods Our 5-year collaborative project will test the feasibility and effectiveness of policy interventions to reduce salt and sugar consumption in Fiji and Samoa, and examine factors that support sustained implementation. We will engage government agencies and civil society in Fiji and Samoa, to support the design, implementation and monitoring of evidence-informed interventions. Specific objectives are to: (1) conduct policy landscape analysis to understand potential opportunities and challenges to strengthen policies for prevention of diet-related NCDs in Fiji and Samoa; (2) conduct repeat cross sectional surveys to measure dietary intake, food sources and diet-related biomarkers; (3) use Systems Thinking in Community Knowledge Exchange (STICKE) to strengthen implementation of policies to reduce salt and sugar consumption; (4) evaluate the impact, process and cost effectiveness of implementing these policies. Quantitative and qualitative data on outcomes and process will be analysed to assess impact and support scale-up of future interventions. Discussion The project will provide new evidence to support policy making, as well as developing a low-cost, high-tech, sustainable, scalable system for monitoring food consumption, the food supply and health-related outcomes.
1) Background: ESports is a new trend of sports, which has gained considerable popularity worldwide. There is a scarcity of evidence that focuses on the lifestyle of ESports players (eSP) particularly on symptoms of nomophobia, level of anxiety, sleep quality, food consumption and physical activity. (2) Objective: to determine the prevalence and relationship between symptoms of nomophobia, psychological aspects, insomnia and physical activity of eSP in Saudi Arabia. (3) Methods: A cross-sectional study was conducted between March and April 2021 using a convenient self-selection adult sample. A total of 893 (216 eSP vs. 677 non-eSP (NeSP)) participants aged over 18 years were included. All participants answered a seven-part validated questionnaire that included: (i) sociodemographic questions; (ii) a symptoms of nomophobia questionnaire; (iii) general anxiety disorder questions, (iv) an insomnia severity index, (v) an Internet addiction scale, (vi) the Yale food addiction scale 2.0 short form and (vii) an international physical activity questionnaire. (4) Results: Among the entire population, the prevalence of moderate to severe nomophobia, anxiety , insomnia, Internet addiction and low physical activity were 29.8%, 13.9%, 63.3%, 27% and 2.8%, respectively. The eSP and NeSP differed significantly in nomophobia scale, anxiety and insomnia values. Compared to NeSP, eSP had a higher level of severe nomophobia p = 0.003, a severe level of anxiety p = 0.025 and symptoms of insomnia p = 0.018. Except for food addiction and physical activity , a positive correlation was identified between symptoms of nomophobia, anxiety and insomnia among eSP. (5) Conclusion: This study reported high prevalence of nomophobia, anxiety and insomnia among eSP compared to NeSP. Citation: AlMarzooqi, M.A.; Alhaj, O.A.; AlRasheed, M.M.; Helmy, M.; Trabelsi, K.; Ebrahim, A.; Hattab, S.; Jahrami, H.A.; Saad, H.B.
Elucidating underlying mechanisms of biocontrol agents (BCAs) could aid in selecting potent BCAs and increasing their biocontrol efficacy. Nutrient competition is an important biocontrol mechanism; however, essential nutrient sources, and contributing genes for nutrient competition still remain to be explored. Pseudomonas putida JBC17 (JBC17WT) suppressed green mold in satsuma mandarins by inhibiting conidial germination of Penicillium digitatum via nutrient competition. To analyze genes essential for biocontrol performance of JBC17WT, we generated a transposon (Tn)-mediated mutant library and selected mutants with the ability to suppress conidial germination. Several mutants in the genes of flagella-formation, including fliR , fliH , and flgG , increased biocontrol performance and enhanced inhibition of conidial germination. They lost swimming motility, exhibited increased growth and rapid carbon and nitrogen utilization than the wild type under nutrient-poor conditions. The nutrient competition assay using polytetrafluoroethylene cylinders revealed that conidial germination was inhibited by nutrient absorption under nutrient-poor conditions. In addition, genes, including amidohydrolase ( ytcJ ), tonB-dependent receptor ( cirA ), argininosuccinate synthase ( argG ), D-3-phosphoglycerate dehydrogenase ( serA ), and chaperone protein ( dnaJ ), were involved in the inhibition of conidial germination. The results of this study indicate that rapid and continuous absorption of nutrients by JBC17WT restrict nutrient availability for conidial germination on nutrient-limited fruit surfaces, thereby decreasing the chances of fungal spores infecting fruits. The high-throughput analysis of Tn mutants of this study highlighted the importance of nutrient competition and the genes that influence biocontrol ability, which contributes to the development of biocontrol applications.
The quantity of edible crops is getting compromised day by day as a result of the increasing human population. The quantity of food items has decreased for various reasons, such as environmental conditions, unavailability of water for farming, and farmers’ lower incomes. The main problem with artificial genetically modified organisms (GMO) is the relative lack of information available in the public domain. Furthermore, the method for development of organisms using genetic engineering seems bizarre to the public. Although certain genetically modified food items of routine use are, subject to regulation, available in the market, there is still sparse knowledge about the items available. Considering such problems, this chapter discusses the pitfalls for the use of GMO in the real world and the advantages of GMOs for the betterment of human society. This chapter discusses the patenting requirements of GMOs, providing detailed and useful information about the problems, and disposes of some prevailing myths. It also provides new insights into solving certain problems in the development of GMOs.
The article defines the influence of structural and operational parameters of a machine-tractor unit on changes in the hardness of freshly plowed soil due to deformation and compaction of the soil by wheeled running systems. An experimental model of the effect of pressure in the pneumatic chamber of the wheel, working width and speed of the unit on changes in soil hardness in the area of operation of running systems is obtained. The obtained mathematical models make it possible to predict changes in soil hardness, which makes it possible to reduce the negative impact on the soil of running systems by optimally completing, configuring and selecting the MTU operating mode.
Background The objective of this research was to use a meta-analysis to understand the prevalence of hepatitis B or C in waste pickers worldwide. Methods Epidemiological studies on hepatitis B and C in waste pickers were included adopting a systematic review with meta-analysis. Each selected article had its quality scored by all authors, evaluated according to the Loney’s criteria, and evaluated for quality and bias verified with a funnel plot. Results After employing Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, there were 12 studies used for this meta-analysis. The rate of hepatitis B seropositivity was 0.15 (95% CI 0.10–0.20), and hepatitis C was 0.08 (95% CI 0.04–0.12). This information suggests that waste pickers are exposed to many risks associated with poor quality of life working conditions as well as low health literacy rates. Conclusion The results of this meta-analysis confirm the vulnerability of waste pickers to hepatitis B and C infection and reinforce the importance of using personal protective equipment and immunizing workers.
Layer manure (LM) and spent mushroom substrate (SMS) are two kinds of nitrogen (N) rich solid wastes generate in the poultry breeding and agriculture production. Composting is an effective way to recycle the LM and SMS. However, a large amount of N in the LM and SMS was lost via volatilization during composting, with negative environmental and economic consequences. This study investigated the effect of incorporating biochar at the ratio of 5%, 10%, and 15% (w/w) during co-composting of LM and SMS on ammonia (NH3) and nitrogen oxide (N2O) volatilization and N retention. After the 35-day composting, the results showed that the pile temperature and seed germination index in biochar treatments were significantly improved in comparison with control treatment. The nitrogen in all treatments was lost in the form of N2O (0.05∼0.1%) and NH3 (13.1∼20.2%). Likewise, the total nitrogen loss was 28.9%, 20.3%, and 24.9%, respectively, of which N2O-N accounts for 0.05∼0.10%. Compared with control treatment, the total amount of NH3 volatilization in biochar treatments of 5%BC, 10%BC and 15%BC was decreased by 21.2%, 33.1%, and 26.1%, respectively. The total amount of N2O emission was decreased by 39.0%, 13.2%, and 1.6%, respectively. Adding 10% and 15% biochar can significantly reduce NH3 volatilization while adding 5% biochar treatment didn’t significantly reduce NH3 emissions but showed the best performance in reducing N2O emission. The addition of 10% biochar in co-composting of LM and SMS is the recommended dosage that exhibited the best performance in improving composting quality and reducing nitrogen loss.
Objective To estimate the proportion of products meeting Fiji government labelling regulations, assess compliance with national sodium reformulation targets, and examine the sodium and total sugar levels in packaged foods sold in selected major supermarkets. Design We selected five major supermarkets in 2018 and collected the product information and nutritional content from the labels of all packaged foods sold. We organised 4,278 foods into 14 major food categories and 36 sub-categories and recorded the proportion of products labelled in accordance with the Fiji labelling regulations. We looked at the levels of sodium and total sugar in each food category and assessed how many products complied with the Fiji reformulation targets set for sodium. We also listed the companies responsible for each product. Setting Suva, Fiji. Results Fourteen percent of packaged foods in fourteen major categories met Fiji national labelling regulations. Sodium was labelled on 95.4% products, and total sugar labelled on 92.4%. The convenience foods category had the highest sodium levels (1699mg/100g) while confectionery had the highest content of total sugar (52.6g/100g). Forty percent of eligible products did not meet the proposed voluntary sodium reformulation targets. Conclusions Our findings indicate significant room for improvement in nutrient labelling, as well as a need for further enforcement of reformulation targets and monitoring of changes in food composition. Through enacting these measures and establishing additional regulations such as mandatory front-of-pack labelling, government and food industry can drive consumers towards healthier food choices and improve the nutritional quality of packaged foods in Fiji.
A unified fundamental equation of state 2,3,3,3-tetrafluoropropene (R1234yf) has been developed, a fourth-generation ozone safe refrigerant, and a method for constructing the equation has been proposed. In the gas region, this equation transforms into the virial equation of state, and in the vicinity of the critical point it satisfies the requirements of the modern large-scale theory of critical phenomena and transforms into the Widom scale equation. On the basis of a single fundamental equation of state in accordance with GOST R 8.614-2018, standard reference data (GSSSD 380-2020) on the density, enthalpy, isobaric heat capacity, isochoric heat capacity, entropy and sound velocity of R1234yf in the temperature range from 230 K to 420 K and pressures from 0.1 MPa to 20 MPa. A comparison of the calculated values of equilibrium properties with the most reliable experimental data obtained in the famous of the world, and tabular data obtained on the basis of the known fundamental equations of state R1234yf. Uncertainties of tabulated data for saturated vapor pressure, density, enthalpy, isobaric heat capacity, isochoric heat capacity, entropy and speed of sound of 2,3,3,3-tetrafluoropropene are estimated – standard relative uncertainties by type A, B, total standard relative and expanded uncertainties. The results obtained in the work show that the proposed unified fundamental equation of state adequately describes the equilibrium properties of R1234yf in the range of state parameters stated above.
Purpose of review: Childhood obesity is increasing substantially in many Pacific island countries and poses an urgent and serious challenge. The Sustainable Development Goals set by the United Nations and the NCD Roadmap created at the request of the Pacific Finance and Economic Ministers identify prevention and control of noncommunicable diseases as core priorities. Among the various risk factors responsible for the development of noncommunicable diseases (NCDs), overweight and obesity are particularly of concern with the potential to negate many of the health benefits that have contributed to increased life expectancy. With the increase in childhood obesity across the region, it has become apparent that surveillance data remains a challenge; however, it is essential to inform the development of effective policies and strategies to tackle the challenge of childhood obesity in the Pacific region. Recent findings: The paper highlights the paucity of childhood obesity surveillance data available in the Pacific region and how the absence of a standardised tool to collect this data makes it difficult to do comparative analysis between countries. Drawing on a global protocol and identifying the gaps that currently exist in the region, the paper aims to highlight opportunities via which childhood obesity surveillance data can be improved to monitor better childhood obesity across the Pacific region.
Background In low-income countries breast cancer awareness (BCA) is essential to reduce the proportion of advanced stage presentations of breast cancer. There is a lack of studies using multivariable techniques to explore factors related to BCA in low-income countries. The objective of this study was to identify to what extent women in Fiji and Kashmir, India have BCA and practice breast self-examination (BSE) as well as factors associated with BCA and BSE. Methods A survey of women aged ≥18 years was conducted in Fiji and Kashmir, India to assess BCA and rates of BSE. Comparison between Fiji and Kashmir was done using student’s t-test for continuous data and chi-square for binary data. Factors associated with BCA and BSE were analysed using a multivariable logistic regression for Fiji and Kashmir separately. Results Data were collected from 399 and 1982 women in Kashmir and Fiji, respectively. Of 1968 women in Fiji 57% were deemed to have an acceptable BCA compared to only 7.3% of 395 women in Kashmir. Having some education was associated with having BCA with an odds ratio of 4.7 (1.7–13) in Fiji and 10 (1.7–59) in Kashmir. Of 1976 women in Fiji 40% had tertiary education while 40% of 392 women in Kashmir had no education at all. The marital status was similar in both samples (n = 1973 and 395) with 68–69% being married and 21–26% being single. The lack of female doctors or nurses with whom to discuss issues, was perceived as a problem in both countries. Conclusions The key finding is an association between having any level of education and BCA. This correlation was much stronger than for a family history of breast cancer and BCA. Hence, general education to illiterate women may reduce the proportion of women in low-income countries presenting with advanced-stage breast cancer.
European pear (Pyrus communis L.) cultivars require a genetically pre-determined duration of cold-temperature exposure to induce autocatalytic system 2 ethylene biosynthesis and subsequent fruit ripening. The physiological responses of pear to cold-temperature-induced ripening have been well characterized, but the molecular mechanisms underlying this phenomenon continue to be elucidated. This study employed previously established cold temperature conditioning treatments for ripening of two pear cultivars, ‘D’Anjou’ and ‘Bartlett’. Using a time-course transcriptomics approach, global gene expression responses of each cultivar were assessed at four stages of developmental during the cold conditioning process. Differential expression, functional annotation, and gene ontology enrichment analyses were performed. Interestingly, evidence for the involvement of cold-induced, vernalization-related genes and repressors of endodormancy release was found. These genes have not previously been described to play a role in fruit during the ripening transition. The resulting data provide insight into cultivar-specific mechanisms of cold-induced transcriptional regulation of ripening in European pear, as well as a unique comparative analysis of the two cultivars with very different cold conditioning requirements.
The origins of spin lifetimes in quantum systems is a matter of importance in several areas of quantum information. Spectrally mapping spin relaxation processes provides insight into their origin and motivates methods to mitigate them. In this paper, we map nuclear relaxation in a prototypical system of 13C nuclei in diamond coupled to Nitrogen Vacancy (NV) centers over a wide field range (1 mT-7 T). Nuclear hyperpolarization through optically pumped NV electrons allows signal measurement savings exceeding million-fold over conventional methods. Through a systematic study with varying substitutional electron (P1 center) and 13C concentrations, we identify the operational relaxation channels for the nuclei at different fields as well as the dominant role played by 13C coupling to the interacting P1 electronic spin bath. These results motivate quantum control techniques for dissipation engineering to boost spin lifetimes in diamond, with applications including engineered quantum memories and hyperpolarized 13C imaging. Nuclear spins in diamond have applications in quantum technologies and NMR methods but their performance can be limited by relaxation processes that are difficult to characterise. Ajoy et al. develop a T1 noise spectroscopy method to identify the dominant relaxation channel and propose a mitigation strategy.
Five new cycloartane saponins, mussaglaosides A–E (1–5) together with five known saponins, mussaendoside O, mussaendoside, G mussaendoside U, mussaendoside P, and mussaendoside Q (6–10) were isolated from the leaves of Mussaenda glabra. Their structures were determined on the basis of extensive spectroscopic methods, including 1D-, 2D-NMR, and MS data. All compounds were evaluated for ANO1 inhibitory activity using calcium-activated chloride channel and YFP expressing HT29 cells. Among the tested compounds, compound 6 strongly inhibited chloride channel activity with IC50 value of 22.0 ± 1.7 μM without any cytotoxicity.
Institution pages aggregate content on ResearchGate related to an institution. The members listed on this page have self-identified as being affiliated with this institution. Publications listed on this page were identified by our algorithms as relating to this institution. This page was not created or approved by the institution. If you represent an institution and have questions about these pages or wish to report inaccurate content, you can contact us here.
1,776 members
Tara Rava Zolnikov
  • Department of Community Health
Vladimir Rotar
  • Department of Mathematics
Igor Yakov Subbotin
  • Mathematics and Natural Sciences
Dana L. Grisham
  • Department of Teacher Education
Peter Serdyukov
  • Department of Teacher Education
11255 North Torrey Pines Road, 92037, San Diego, CA, United States
Head of institution
Dr Michael Cunningham (President & Chancellor)
(800) NAT-UNIV (800-628-8648)
(858) 642-8260