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1.
J Environ Manage ; 365: 121657, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38963958

RESUMO

Grazing lands play a significant role in global carbon (C) dynamics, holding substantial soil organic carbon (SOC) stocks. However, historical mismanagement (e.g., overgrazing and land-use change) has led to substantial SOC losses. Regenerative practices, such as adaptive multi-paddock (AMP) grazing, offer a promising avenue to improve soil health and help combat climate change by increasing SOC accrual, both in its particulate (POC) and mineral-associated (MAOC) organic C components. Because adaptive grazing patterns emerge from the combination of different levers such as frequency, intensity, and timing of grazing, studying AMP grazing management in experimental trials and representing it in models remains challenging. Existing ecosystem models lack the capacity to predict how different adaptive grazing levers affect SOC storage and its distribution between POC and MAOC and along the soil profile accurately. Therefore, they cannot adequately assist decision-makers in effectively optimizing adaptive practices based on SOC outcomes. Here, we address this critical gap by developing version 2.34 of the MEMS 2 model. This version advances the previous by incorporating perennial grass growth and grazing submodules to simulate grass green-up and dormancy, reserve organ dynamics, the influence of standing dead plant mass on new plant growth, grass and supplemental feed consumption by animals, and their feces and urine input to soil. Using data from grazing experiments in the southeastern United States and experimental SOC data from two conventional and three AMP grazing sites in Mississippi, we tested the capacity of MEMS 2.34 to simulate grass forage production, total SOC, POC, and MAOC dynamics to 1-m depth. Further, we manipulated grazing management levers, i.e., timing, intensity, and frequency, to do a sensitivity analysis of their effects on SOC dynamics in the long term. Our findings indicate that the model can represent bahiagrass forage production (BIAS = 9.51 g C m-2, RRMSE = 0.27, RMSE = 65.57 g C m-2, R2 = 0.72) and accurately captured the dynamics of SOC fractions across sites and depths (0-15 cm: RRMSE = 0.05; 15-100 cm: RRMSE = 1.08-2.07), aligning with patterns observed in the measured data. The model best captured SOC and MAOC stocks across AMP sites in the 0-15 cm layer, while POC was best predicted at-depth. Otherwise, the model tended to overestimate SOC and MAOC below 15 cm, and POC in the topsoil. Our simulations indicate that grazing frequency and intensity were key levers for enhancing SOC stocks compared to the current management baseline, with decreasing grazing intensity yielding the highest SOC after 50 years (63.7-65.9 Mg C ha-1). By enhancing our understanding of the effects of adaptive grazing management on SOC pools in the southeastern U.S., MEMS 2.34 offers a valuable tool for researchers, producers, and policymakers to make AMP grazing management decisions based on potential SOC outcomes.


Assuntos
Carbono , Solo , Solo/química , Carbono/análise , Animais , Mudança Climática , Ecossistema , Agricultura/métodos , Poaceae
2.
Data Brief ; 55: 110585, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38974004

RESUMO

Wheat (Triticum aestivum) is a major cereal crop planted in the Southern Great Plains. This crop faces diverse pests that can affect their development and reduce yield productivity. For example, aphids are a significant pest in wheat, and their management relies on pesticides, which affect the sustainability and biodiversity of natural predators that prey on aphids. Coccinellids, commonly named lady beetles, are the most abundant natural predators of wheat. These natural enemies contribute to the natural predation of aphids, which can reduce the use of excessive pesticides for aphid management. Usually, visual observations of these natural enemies are performed during pest sampling; however, it is time-consuming and requires manual labor, which can be expensive. An automation system or detection models based on machine learning approaches that can detect these insects is needed to reduce unnecessary pesticide applications and manual labor costs. However, developing an automation system or computer vision models that automatically detect these natural enemies requires imagery to train and validate this cutting-edge technology. To solve this research problem, we collected this dataset, which includes images and label annotations to help researchers and students develop this technology that can benefit wheat growers and science to understand the capabilities of automation in Entomology. We collected a dataset using mobile devices, which included a diverse range of coccinellids on wheat images. The dataset consists of 2,133 images with a standard size of 640 × 640 pixels, which can be used to train and develop detection models for machine learning purposes. In addition, the dataset includes annotated labels that can be used for training models within the YOLO family or others, which have been proven to detect small insects in crops. Our dataset will increase the understanding of machine learning capabilities in entomology, precision agriculture, education, and crop pest management decisions.

3.
Transl Anim Sci ; 8: txae042, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562214

RESUMO

Penetrating captive bolt (PCB) is the primary method of preslaughter stunning for cattle and is also used for on-farm euthanasia. The objective of this study was to quantify the impact of cooling on the soft tissue thickness, cranial thickness, total tissue thickness, and cross-sectional brain area of cadaver heads collected from mature (> 30 mo of age) dairy cows following the application of a PCB stun in a frontal placement. Hide-on cadaver heads were obtained from culled dairy cows (N = 37) stunned in a frontal location using a handheld PCB device (Jarvis Model PAS-Type C 0.25R Caliber Captive Bolt, Long Bolt) at a commercial slaughter establishment. Following transport to the University of Wisconsin-River Falls, heads were split at midline along the bolt path by a bandsaw and then underwent FRESH, CHILL24, CHILL48, and CHILL72 refrigeration treatments. The FRESH treatment involved images collected immediately after splitting each head, the CHILL24 treatment involved images collected after 24 h of refrigeration, the CHIL48 treatment involved images collected after 48 h of refrigeration, and the CHILL72 treatment involved images collected after 72 h of refrigeration. Measurements of soft tissue thickness, cranial thickness, total tissue thickness, and cross-sectional brain area were recorded for each refrigeration treatment. Soft tissue thickness did not differ caudal to (P = 0.3751) or rostral to (P = 0.2555) the bolt path. Cranial thickness did not differ caudal to (P = 0.9281) or rostral to (P = 0.9051) the bolt path. Total tissue thickness did not differ caudal to (P = 0.9225; FRESH: 24.77 mm, CHILL24: 23.93 mm, CHILL48: 24.27 mm, CHILL72: 42.30, SE: 0.86) or rostral to (P = 0.8931; FRESH: 24.09 mm, CHILL24: 23.99, CHILL48: 24.26, CHILL72: 24.43 mm, SE: 0.79 mm) the bolt path. Cross-sectional brain area was not different (P = 0.0971) between refrigeration treatments (FRESH: 9,829.65 ±â€…163.87 mm2, CHILL24: 10,012.00 ±â€…163.87 mm2, CHILL48: 9,672.43 ±â€…163.87 mm2, CHILL72: 10,235.00 ±â€…166.34 mm2). This study demonstrated that FRESH tissue parameters can be determined from cattle cadaver heads refrigerated for 24, 48, or 72 h.

4.
Sex Educ ; 21(1): 27-43, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-38343724

RESUMO

Adolescence is a period of exploration of sexuality and of its integration into personality. Existing research on Latina adolescents, however, has been largely limited to disease and pregnancy prevention, ignoring the integration of sexual well-being with other aspects of health. Accordingly, this paper presents findings from a photovoice project with 11-12 year old Latina students, implemented to investigate topics related to cultural identity, gender and sexual health. The data were generated over a 12-week period in an urban middle school in Central Texas by 17 youth collaborators. Findings provide a platform for discussion of how Latina young people's ideas align with or diverge from current sexual health discourses within a racial/ethnic context. We highlight opportunities and constraints with regard to identifying sexual health needs from young Latina students' own perspectives, in an attempt to contribute to the body of literature on sexual health in middle school students, as well as the lessons learned through our efforts.

6.
Sex Roles ; 77(7-8): 453-470, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38818107

RESUMO

Utilizing grounded theory methodology and drawing from sexual script theory as a research lens, we examined familial gender ideologies, media portrayals of Black and Latina women, dating attitudes, and sexual behaviors among 33 low-income early adolescent (aged 11-14) African American and Mexican American young women. Themes revealed divergent experiences for African American and Mexican American young women. In particular, African American participants reported egalitarian familial gender ideologies and sexual objectification of Black women, as well as more open and positive attitudes toward dating and sexuality. In contrast, Mexican American participants reported patriarchal familial gender ideologies and the portrayed mistreatment of Latinas in telenovelas and Spanish language songs, along with cautious attitudes towards dating and sexuality. Additionally, Mexican American participants reported that they censored their communication about sexual matters with their family. Overall, findings suggest that interventions should be tailored accordingly for African American and Mexican American youth. Interventions with African American young women should focus on providing accurate information on safer sexual practices, whereas interventions with Mexican American young women should focus on promoting constructive conceptualizations of gender roles, which could help foster self-efficacy around sexual communication with parents and potential partners.

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