191 research outputs found
Characteristics of multipleâyear nitrous oxide emissions from conventional vegetable fields in southeastern China
The annual and interannual characteristics of nitrous oxide (N2O) emissions from conventional vegetable fields are poorly understood. We carried out 4 year measurements of N2O fluxes from a conventional vegetable cultivation area in the Yangtze River delta. Under fertilized conditions subject to farming practices, approximately 86% of the annual total N2O release occurred following fertilization events. The direct emission factors (EFd) of the 12 individual vegetable seasons investigated ranged from 0.06 to 14.20%, with a mean of 3.09% and a coefficient of variation (CV) of 142%. The annual EFd varied from 0.59 to 4.98%, with a mean of 2.88% and an interannual CV of 74%. The mean value is much larger than the latest default value (1.00%) of the Intergovernmental Panel on Climate Change. Occasional application of lagoonâstored manure slurry coupled with other nitrogen fertilizers, or basal nitrogen addition immediately followed by heavy rainfall, accounted for a substantial portion of the large EFds observed in warm seasons. The large CVs suggest that the emission factors obtained from shortâterm observations that poorly represent seasonality and/or interannual variability will inevitably yield large uncertainties in inventory estimation. The results of this study indicate that conventional vegetable fields associated with intensive nitrogen addition, as well as occasional applications of manure slurry, may substantially account for regional N2O emissions. However, this conclusion needs to be further confirmed through studies at multiple field sites. Moreover, further experimental studies are needed to test the mitigation options suggested by this study for N2O emissions from open vegetable fields
Idiopathic desmoid-type fibromatosis of the pancreatic head: case report and literature review
Desmoid-type fibromatosis (DTF) is an uncommon nonmetastatic fibrous neoplasm. Sporadic intraperitoneal DTF is rarely described in current literature. We herein report a case of DTF of unknown cause involving the pancreatic head. A 41-year-old man presented with recurrent epigastric pain and weight loss. An abdominal computed tomography scan showed a well-delineated solid cystic mass inside the pancreatic head. Pylorus-preserving pancreaticoduodenectomy was performed due to the patientâs debilitating symptoms and suspected malignancy. The pathological examination revealed massive fibroblastic proliferation arising from the musculoaponeurotic tissues, consistent with a diagnosis of DTF. Immunohistochemical phenotyping determined positive immunoreactivity to vimentin and β-catenin, but negative immunoreactivity to smooth muscle actin, CD117, CD34, or S-100, confirming the diagnosis of DTF. No local recurrence or distant metastasis was found during a 24-month follow-up. Radical resection is recommended as first-line treatment for pancreatic DTF. Long-term follow-up studies are required to establish the prognosis of pancreatic DTF
Features of training specialists in the field of environmental safety in water resources management
The article substantiates the necessity of transforming the educational process to train specialists in the field of environmental safety in water resources management. The main peculiarity of labor functions performed by such specialists is in the randomness and secrecy of natural processes and the appearance of consequences from any type of activity over a long period of time. It is necessary to understand the cause-and-effect relationships between processes and the individual parameters that affect the speed of their realization in order to solve such problems. The result of the research was the development of the training concept, which allows the presentation of a task as a set of elementary actions that require particular resource support for their fulfillment. Potentially possible problems in their fulfillment are determined. It is recommended that models of âdigital twinsâ of systems capable of imitating the reaction to certain influences be used to improve the efficiency of the educational process and perform highly specialized actions
Five newly recorded species of angiosperms from Shanxi Province
Abstract [Objective] The aim is to enrich the angiosperm germplasm resources in Shanxi Province, and
promote research on biodiversity and forest ecosystems in Zhongtiao Mountain area. [Methods] Photoes of
plant specimens and their typical features from Zhongtiao Mountains were collected through specimen identification,
data access, and expert consultation, by conducting an extensive field survey of vegetation.
[Results] Five species of angiosperms were newly recorded in Shanxi Province, including viz. Rumex acetosella
L., Anemone narcissiflora subsp. protracta (Ulbrich) Ziman & Fedoronczuk, Cardamine flexuosa
With., Impatiens lushiensis Y. L. Chen, and Physalis minima L.. [Conclusion] These plants belong
to 5 families and 5 genera, which are newly recorded species of angiosperms from Shanxi Province. These
discoveries enrich the angiosperms germplasm resources and provide a basis for the study of plant diversity
and florogenesis in Zhongtiao Mountain Area
Specifics of training specialists in the field of water resources logistics
The article defines the problem of training specialists who manage water resources logistics. The problems of water logistics are related to peculiarities of transportation of water resources in order to preserve their quality characteristics, operation of hydraulic structures, preservation of coastal territories and their corresponding ecosystems. Effective implementation of the processes related to the above features requires constant analysis of a multitude of parameters and processes, which in most cases are random in nature. The development of operational management solutions requires the use of specialized intelligent software tools. Their effective use requires professional training. The study developed a model of the educational process that uses technologies of digital twins of real natural objects, which allowed forming professional competencies in the field of water resources logistics in an interactive form
Association between behavioral patterns and depression symptoms: dyadic interaction between couples
BackgroundBehavioral patterns are sometimes associated with depression symptoms; however, few studies have considered the intra-couple effects. This study examined the effect of a spousesâ behavioral patterns on depression symptoms within themself and in their spouse.MethodsA total of 61,118 childbearing age participants (30,559 husband-wife dyads) were surveyed. The depression symptoms were assessed using the nine-item Patient Health Questionnaire (PHQ-9). The behavioral patterns were identified by the latent class analysis. The effects of behavioral patterns on the coupleâs own depression symptoms (actor effect) and their partnerâs depression symptoms (partner effect) were analyzed using the Actor-Partner Interdependence Model (APIM).ResultsThree behavioral patterns were identified: low-risk group, moderate-risk group, and high-risk group. The high risk of these behavior patterns would be associated with a higher score on the PHQ-9; for both husbands and wives, their behavioral patterns were positively associated with PHQ-9 scores (βhusband = 0.53, P < 0.01; βwife = 0.58, P < 0.01). Wivesâ behavioral patterns were also positively associated with their husbandsâ PHQ-9 scores (β = 0.14, P < 0.01), but husbandsâ behavioral patterns were not associated with their wivesâ PHQ-9 scores.ConclusionsWivesâ depression symptoms were affected only by their own behavioral patterns, whereas husbandsâ depression symptoms were influenced by both their own and their spousesâ behavioral patterns
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