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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： Francis Levi A.DURANO Jon Marx SARMIENTO larry N.DIGAL Pedro A.ALVIOLA IV School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. with an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

Importance of Stewards and Other Protection Efforts for Conservation of Red Knots (Calidris canutus rufa) and Other Shorebirds on Delaware Bay, New Jersey

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Natural Science 2024年第9期16卷 162-182页

作者： Joanna Burger Amanda Dey larry Niles Division of Life Sciences Rutgers University Piscataway NJ USA wildlife Restoration Partnerships 109 Market Lane Greenwich NJ USA

Understanding the factors that contribute to population stability in long-distance migrant birds is increasingly important, particularly given global climate change, sea level rise, and loss or disturbance at essential habitats. while the populations of most shorebirds are declining worldwide, those that migrate through Delaware Bay, New Jersey and Delaware, are declining at the most rapid rate despite conservation efforts. In this paper, we 1) provide background information on population declines of red knots (Calidris canutus rufa) using Delaware Bay, threats to their foraging, and efforts to reduce threats, 2) summarize briefly our studies of the effects of human activities on knots and other shorebirds, 3) present data on management efforts to protect knots and other shorebirds from the activities of people, and 4) discuss the efficacy of such efforts (usually referred to as “decreasing the effect of human disturbances”). The Shorebird Project on Delaware Bay is over 25 years old and provides long-term data to help assess the status of shorebird numbers, particularly for red knot, as well as the density of horseshoe crabs (Limulus polyphemus) and their eggs. Red knots have continued to decline even more precipitously in the last few years, presenting cause for concern. Protective efforts have been successful in reducing human disruption on the N.J. Delaware Bay beaches, but the lack of uniformity in implementation across the New Jersey side, and across the whole Bay have hampered further improvements. Implementation of signs, fencing, and stewards on some beaches significantly enhanced the use of these beaches by red knots, determined by examining the use of beaches pre- and post-implementation. Implementation of fencing and stewards had the greatest effect. From 1986 to 2018, there was a significant shift in the percent of Delaware Bay red knots using the NJ side, where protection efforts had been implemented on many of the beaches. Merely restricting access (w

关键词： Red Knot Calidris canutus rufa Conservation Beach Monitors Human Disturbance Habitat Restoration Management Stewards Education Population Declines Coastal

Advanced Photonics:Thank you for five wonderful years

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Advanced Photonics 2024年第1期6卷 5-5页

作者： Anatoly V. Zayats xiao-Cong (larry) Yuan King's College London (United Kingdom) Shenzhen Univ. (China)

As we mark the fifth anniversary of Advanced Photonics,we are filled with immense pride and gratitude for the remarkable journey we have undertaken together with our authors,readers,reviewers,Editorial Board,and *** the past half-decade,the journal has fostered groundbreaking research and facilitated discussions on the most innovative topics of optics and *** is reflected in our current standing as one of the top five journals in optics.

关键词： journal optics discussions

Assessment of groundwater quantity, quality, and associated health risk of the Tano river basin, Ghana

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Acta Geochimica 2024年第2期43卷 325-353页

作者： Adwoba Kua-Manza Edjah Bruce Banoeng-Yakubo Anthony Ewusi Enoch Sakyi-Yeboah David Saka Clara Turetta Giulio Cozzi David Atta-Peters larry Pax Chegbeleh water Resources Research Centre Ghana Atomic Energy CommissionAccraGhana Earth Science Department University of GhanaLegonAccraGhana Geological Engineering Department University of Mines and TechnologyTarkwaGhana Department of Statistics University of GhanaAccraLegonGhana Institute of Polar Sciences National Research Council of ItalyVeniceItaly

In the Tano River Basin,groundwater serves as a crucial resource;however,its quantity and quality with regard to trace elements and microbiological loadings remain poorly understood due to the lack of groundwater logs and limited water *** study presents a comprehensive analysis of the Tano River Basin,focusing on three key ***,it investigated the aquifer hydraulic parameters and the results showed signiﬁcant spatial variations in borehole depths,yields,transmissivity,hydraulic conductivity,and speciﬁc *** boreholes were concentrated in the northeastern and southeastern zones,while geological formations,particu-larly the Apollonian Formation,exhibit a strong inﬂuence on borehole *** study identiﬁed areas with high transmissivity and hydraulic conductivity in the southern and eastern regions,suggesting good groundwater avail-ability and suitability for sustainable water ***-ondly,the research investigated the groundwater quality and observed that the majority of borehole samples fall within wHO(Guidelines for Drinking-water Quality,Environmental Health Criteria,Geneva,2011,***://***)***,some samples have pH levels below the standards,although the groundwater generally qualiﬁes as *** study further explores hydrochemical facies and health risk assessment,highlighting the dominance of Ca–HCO3 water *** element analysis reveals minimal health risks from most elements,with chromium(Cr)as the primary contributor to chronic health ***,this study has provided a key insights into the Tano River Basin’s hydrogeology and associated health *** outcome of this research has contributed to the broader understanding of hydrogeologi-cal dynamics and the importance of managing groundwater resources sustainably in complex geological environments.

关键词： Groundwater Unsupervised machine learning technique Hydrochemistry Aquifer hydraulic parameter Health risk

Petrophysical Evaluation of Cape Three Points Reservoirs

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International Journal of Geosciences 2024年第2期15卷 162-179页

作者： Striggner Bedu-Addo Sylvester Kojo Danuor larry Pax Chegbeleh Department of Physics Kwame Nkrumah University of Science and Technology Kumasi Ghana Department of Earth Science University of Ghana Accra Ghana

The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the western basin with a view to describe the reservoir quantitatively using well Logs, Petrel and Techlog. The investigated characteristics, which were all deduced from geophysical wire-line logs, include lithology, porosity, permeability, fluid saturation, and net to gross thickness. To characterise the reservoir on the field, a suite of wire-line logs including gamma ray, resistivity, spontaneous potential, and density logs for three wells (wELL_1x, wELL_2x, and wELL_3x) from the Tano Cape Three Point basin were studied. The analyses that were done included lithology delineation, reservoir identification, and petrophysical parameter determination for the identified reservoirs. The tops and bases of the three wells analysed were marked at a depth of 1203.06 - 2015.64 m, 3863.03 - 4253.85 m and 2497.38 - 2560.32 m respectively. There were no hydrocarbons in the reservoirs from the studies. The petrophysical parameters computed for each reservoir provided porosities of 13%, 3% and 11% respectively. The water saturation also determined for these three wells (wELL_1x, wELL_2x and wELL_3x) were 94%, 95% and 89% respectively. These results together with the behaviour of the density and neutron logs suggested that these wells are wildcat wells.

关键词： Petrophysical Cape Three Points Reservoirs

Increased Mortality Risk in Children with Fetal Alcohol Spectrum Disorders: A Scoping Review

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Open Journal of Pediatrics 2024年第4期14卷 754-766页

作者： Devin Evavold Tyler Mueller Erika Johnson Marilyn G. Klug larry Burd School of Medicine and Health Sciences University of North Dakota Grand Forks USA

Objective: Fetal Alcohol Spectrum Disorders (FASDs) are common, often undiagnosed, lifelong developmental disorders that result from prenatal alcohol exposure. FASD is present at birth and typically identified around seven years of age. The most severe outcome in cases of FASD is mortality. The purpose of this scoping review is to 1) use a systematic review to provide an estimated mortality proportion for children with FASD, and 2) update a study published in 2014 by reviewing published reports of mortality in individuals diagnosed with FASD. Method: A search of PubMed, CINAHL, and Google Scholar for reports published between 2013 and 2023 on mortality in individuals with FASD. Results: Three population-based studies have reported on all-cause mortality rates, finding a combined mortality rate of 10.9%, a 2.63 fold (95% CI: 2.61 to 2.65) increase in mortality risk over the general population. Since 2016, this review identified only eight new cases meeting the study inclusion criteria. The reported causes of death were five cases of pneumonia, and one case each of failure to thrive and dehydration, intestinal dilatation and asphyxiation caused by overeating due to pica, and acute gastric volvulus. Discussion: while current research suggests a diagnosis of FASD is associated with a 2.6-fold increase in mortality risk, this is likely an underestimation, as most cases of FASD-related mortality go unreported. Globally, about 1 new case is reported every 15 months. However, in the United States alone, between 1752 to 4400 FASD related deaths occur annually. Our review suggests that FASD is rarely identified as a causal or contributing factor in deaths of children and adolescents, resulting in a substantial undercount of FASD-related deaths. Increased attention to the role of FASD in infant and child mortality case reviews, child death review committee reports, and mortality reviews is needed.

关键词： Fetal Alcohol Spectrum Disorders Mortality Birth Defects Death Exposure Pneumonia

Is a Mini-Screen for Fetal Alcohol Spectrum Disorder Feasible?

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Open Journal of Pediatrics 2024年第4期14卷 767-781页

作者： Tyler Mueller Devin Evavold June-Yung Kim Marilyn G. Klug larry Burd School of Medicine and Health Sciences University of North Dakota Grand Forks USA Department of Social work University of North Dakota Grand Forks USA

Background: Fetal Alcohol Spectrum Disorders (FASDs) are a global public health concern with lifelong consequences for affected individuals. Recent prevalence studies suggest FASD prevalence rates range from 1-5% among school age children. Most people with FASD are not correctly diagnosed and inadequate screening to identify patients with increased risk may contribute to under-diagnosis. This study developed a 10-item screening tool for FASD and examined its feasibility. Methods: The sample consisted of 355 children who had been evaluated at an FASD clinic. Data from the 33-item Alcohol Related Neurodevelopmental Disorder Behavioral Checklist was used to develop a brief FASD screen by comparing the changes in Cronbach’s alpha for different combinations of items. The validity of the brief scale was then further examined using receiving operating characteristic analyses. Results: The 10-item screen demonstrated acceptable sensitivity, specificity, and accuracy to identify children at high risk for FASD. The percentage correctly classified was 91.3 and the area under the receiving operating characteristic curve was 0.971. Conclusions: This feasibility study demonstrated that a screen for FASD consisting of 10 items with yes or no responses can be completed in 3 - 4 minutes. The tool is brief, with a low administration burden and has acceptable epidemiologic performance characteristics including accuracy. Future research should examine the performance of this tool when used in larger, community-based populations where screening for FASD would be appropriate.

关键词： Fetal Alcohol Spectrum Disorders (FASDs) Children Screening Prevalence

On the uncertainty of interwell connectivity estimations from the capacitance-resistance model

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Petroleum Science 2014年第2期11卷 265-271页

作者： Gustavo A Moreno larry w Lake YPF Macacha Güemes 515 YPF-Tecnología Baradero S/N (1925) Center for Petroleum and Geosystems Engineering University of Texas at Austin

The capacitance-resistance model （CRM） is an alternative to conventional reservoir simulation. CRM, a simplification of complex numerical models, uses production and injection rates to infer a reservoir description. There is no prior geologic model. The principal output of CRM fitting is the fraction of injected fluid （usually water） that is produced at a producer at steady-state. These fractions are interwell connectivities. Interwell connectivities are fundamental information needed to manage waterfloods in oil reservoirs. The data-driven CRM is a fast tool to estimate these parameters in mature fields and allows one to make full use of the dynamic data available. This paper considers the problem of setting an upper bound on the uncertainty of interwell connectivities for linear-constrained models. Using analytical bounds and numerical simulations, we derive a consistent upper limit on the uncertainty of interwell connections that can be used to quantify the information content of a given dataset.

关键词： Data-driven models capacitance-resistance model secondary recovery waterfloodoptimization interwell connectivities

Input signal design to estimate interwell connectivities in mature fields from the capacitance-resistance model

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Petroleum Science 2014年第4期11卷 563-568页

作者： Gustavo A.Moreno larry w.Lake YPF-Tecnología Baradero S/N (1925) EnsenadaBuenos AiresArgentina YPF Macacha Guemes 515CABAArgentina CPARM University of Texas at AustinAustinTXUSA

Interwell connectivities are fundamental parameters required to manage waterfloods in oil reservoirs. Data-driven models, such as the capacitance-resistance model （CRM）, are fast tools to estimate these parameters from time-correlations of input （injection rates） and output （production rates） signals. Noise and structure of the input time-series impose limits on the information that can be extracted from a given data-set. This work uses the CRM to study general prescriptions for the design of input signals that enhance the information content of injection/production data in the estimation of well-to-well interactions. Numerical schemes and general features of the optimal input signal strategy are derived for this problem.

关键词： Intervell connectivity capacitance-resistance model mature field experiment design