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Effect of in-row spacing on weed suppression and yield of ‘Covington’ and ‘Monaco’ sweetpotato
Get PDFOrganic sweetpotato growers have limited effective weed management options, and most rely on in-season between-row cultivation and hand weeding, which are time consuming, are costly, and deteriorate soil quality. Studies were conducted at the Samuel G. Meigs Horticulture Research Farm, Lafayette, IN, and at the Southwest Purdue Agricultural Center, Vincennes, IN, in 2022 and 2023 to determine the effects of in-row plant spacing and cultivar selection on weed suppression and organic sweetpotato yield. The experiment was a split-split plot design, with in-row spacings of 20, 30, and 40 cm as the main plot factor, weeding frequency (critical weed-free period and weed-free) as the subplot factor, and sweetpotato cultivar (‘Covington’ and ‘Monaco’) as the sub-subplot factor. However, in 2022, we evaluated only in-row spacing and weeding frequency because of the poor establishment of ‘Monaco’. In 2023, sweetpotato canopy at 5 wk after transplanting (WAP) decreased as in-row spacing increased from 20 to 40 cm, and sweetpotato canopy cover of ‘Monaco’ (62%) was greater than that of ‘Covington’ (44%). In-row spacing did not affect weed density at 4, 5, and 6 WAP. As in-row spacing increased from 20 to 40 cm, total sweetpotato yield pooled across both locations in 2023 decreased from 30,223 to 21,209 kg ha−1 for ‘Covington’ and from 24,370 to 20,848 kg ha−1 for ‘Monaco’; however, jumbo yield increased for both cultivars. Findings from this study suggest that an in-row spacing of 20 cm may provide greater yield than the standard spacing of 30 cm for both ‘Monaco’ and ‘Covington’
The Role of Vocal Development Patterns: Predicting Neurogenetic Risk in Infancy Using Early Vocal Development and Sex
Get PDFExtant literature documents a higher rate of language/speech disorders in males; however, despite sex being a potential moderator of outcomes, we do not know what role it plays in early vocal behavior of infants at high risk for such disorders. The purpose of this study was to ask: (1) Do high-risk infants demonstrate atypical vocal development patterns? (2) Is the quality and quantity of early babble distinct for male and female infants, and does this pattern vary across risk? To answer these questions, we examined the canonical babbling ratio (CBR; the ratio of canonical syllables, those with a consonant and vowel, like “ba,” to all babbled syllables) and number of babbled syllables in data collected from 89 high-and low-risk 6-to 18-month- olds. The infants were divided into four groups: infants with Angelman, Down, and fragile X syndromes, and infants at low risk for speech and language disorders. Each participant was recorded for one day using a digital recorder. After recording, speech produced by the infant was extracted and annotated by 3 trained undergraduate coders for the number of canonical and other syllables produced. We ran ANOVAs to explore group and sex differences, which revealed a main effect of risk group, but no main effects or interactions of sex with our dependent variables (number of syllables, CBR). Thus, results revealed group differences, but not effects of sex, suggesting that sex does not relate to risk in vocal production, which could contribute to improved early diagnosis of speech and language disorders
Biodiesel Transesterification of Spent Coffee Grounds Using DBU as a Catalyst: Using DBU to Make Biodiesel from Coffee Grounds
Get PDFCoffee is one of the most universally consumed beverages. The world produces 60 million tons of spent coffee grounds (SCGs) as waste per year. Biodiesel made from SCGs is an eco-friendly alternative fuel but proves difficult to produce. 1,8-Diazabicyclo[ 5.4.0]undec-7- ene (DBU) was used as both a solvent and a catalyst with methanol to determine the efficiency of biodiesel production from SCGs. The process was completed by extracting coffee oil from acid-washed spent coffee grounds (AWSCGs) using hexane. The two extraction methods that were explored were Soxhlet and agitation. DBU is an interesting choice as a solvent and a catalyst because of its ability to change polarities when exposed to carbon dioxide or nitrogen. However, it was shown through experimentation that the product had large crystals and copious amounts of glycerol while producing negligible amounts of biodiesel. Both AWSCGs and regular SCGs were tested along with variations of DBU and methanol volumes, but the results show an insufficient yield in each case. From this, it can be concluded that using DBU as a solvent and catalyst with methanol and coffee oil for production of biodiesel is ineffective. Future experiments to convert SCGs into biodiesel should look for other catalysts and ways to optimize reaction conditions for biodiesel production
Alumni Spotlight: Chufan Gao
Get PDFChufan Gao published an article in volume 8 (2018) of the Journal of Purdue Undergraduate Research during his time spent completing his baccalaureate degree
Alumni Spotlight: Emma Wallens
Get PDFEmma Wallens published an article in volume 8 (2018) of the Journal of Purdue Undergraduate Research during her time spent completing her baccalaureate degree
Proposal of a Private Caretaker-Completed Questionnaire to Assess the Suitability of Domestic Cats for Animal-Assisted Interventions
Get PDFThe objective of this study was to develop a caretaker-completed questionnaire entitled “Cats’ Behavioral Suitability for Animal-Assisted Interventions” (CatSAAI), covering two categories of items associated with seven feline personality factors. These feline personality factors were previously identified and validated by Mikkola et al. (2021) on a large sample of domestic cat guardians. The aim of the CatSAAI questionnaire is to facilitate the interpretation of the behavioral suitability or unsuitability of each individual cat for inclusion in feline-assisted interventions, while considering the prevention of stress and risks in AAI settings for both people and animals. The tool was proposed by an international team of experts in animal behavior and AAI practitioners within the Erasmus+ Project “Animals for People,” which involves partners from Poland, Switzerland, Norway, and Romania. The process of the elaboration of the CatSAAI questionnaire included three steps: (1) grouping of the items identified by Mikkola et al. (2021) in two categories: suitability and unsuitability of cats for AAI; (2) analysis (psychometric and correlational analyses) of the responses of initially collected data from 51 private cat caretakers from six countries, and (3) elimination of several items based on statistical outcomes and expert validation and elaboration of the final form of the survey. The final version of the suitability category contains 28 items belonging to the feline personality factors: activity/playfulness (14 items), sociability toward humans (13 items), and sociability toward cats (1 item), while the unsuitability category consists of 16 items belonging to the following feline personality factors: aggression toward humans (10), fearfulness (3), excessive grooming (2), and activity/playfulness (1)
High Tunnel Bell Pepper Spacing Trial
Get PDFThe objective of this trial is to determine an optimum spacing for bell peppers grown in a high tunnel production system. Six different spacing treatments were evaluated in this trial. Results from this study suggest that tighter plant spacing increased yield per unit area (100 feet of linear row) but decreased the yield per plant
Letter Writing and Legal Consciousness during World War I
No full textThis article explores how ordinary Americans thought about law during WWI by examining 119 letters to Congress regarding charges under the Espionage Act. These letters are a product of their time and shed new light on our understanding of the First Red Scare. This lens of legal consciousness explains how people remain within established modes of engagement, rather than either withdrawing or becoming violent, as is found in the extant literature. Despite opposing goals, the letter writers’ shared master frame enabled them to “speak to” the other side, rather than “past” those with opposing views. This article explains how individuals who opposed and supported seating Berger rallied under the same master frame of Americanism. Yet, the two groups displayed strikingly different legal consciousness. These disparate groups not only conceptualized the law itself differently, but engaged the law as a tool for different agendas. At a time when violence was on the rise, these people eschewed violent means and maintained the most conventional, peaceful means of protest: letter writing. How did they managed this was by embracing the law as their key, nonviolent tool
Impact Analysis of Roadway Surface and Vehicle Conditions on Fleet Formation for Connected and Automated Vehicles
Get PDFTaking advantage of the rapid development of vehicle control and communication technologies, many studies have suggested that operating vehicles in platoons in the future would help improve the safety and efficiency of the transportation system. Although vehicles in a platoon can share data from V2/V communication, a platoon model built on proper control laws is needed to keep the formation of the vehicle fleet and take the real advantage in platoon operations in an environment encompassing different pavement, roadway, and tire conditions. This research introduces a platoon model using a headway-based distance control policy to maintain stability and reduce errors in inter-vehicle spacing. After defining the stability condition and estimating the model parameters, simulation runs are carried out to show that the proposed model is able to keep a small inter-vehicle spacing, follow leader vehicle’s speed, and adjust for changes in acceleration by all the vehicles in the platoon under the influence of vehicle characteristics and roadway frictions