scholarly journals A Critical Review on Mathematical Descriptions to Study Flux Processes and Environmental-Related Interactions of Mangroves

2021 ◽  
Vol 13 (12) ◽  
pp. 6970
Author(s):  
Jefferson Brooks ◽  
Miguel Chen Chen Austin ◽  
Dafni Mora ◽  
Nathalia Tejedor-Flores

Trees are resources that provide multiple benefits, such as the conservation of fauna, both terrestrial and marine, a source of food and raw material, and offering protection in storms, which makes it practical to understand their behavior against different phenomena. Such understanding may be possible through process modeling. Studies confirm that mangrove forests can store more carbon than other forests, influencing the fight against global warming. Thus, a critical and systematic review was carried out regarding studies focusing on mangroves to collect information on the models that have been applied and the most influential variables highlighted by other authors. Applying a systematic search for the most relevant topics related to mangroves (basic as well as recent information), it is possible to group models and methods carried out by other authors to respond to certain behaviors presented by mangroves. Moreover, possible structuring of a mathematical model applied to a species of interest thanks to the analyzed references could provide justified information to the authorities on the importance of these forests and the benefits of their preservation and regeneration-recovery.

2009 ◽  
Vol 160 (7) ◽  
pp. 195-200
Author(s):  
Reto Hefti

In the mountainous canton Grisons, much visited by tourists, the forest has always had an important role to play. New challenges are now presenting themselves. The article goes more closely into two themes on the Grisons forestry agenda dominating in the next few years: the increased use of timber and climate change. With the increased demand for logs and the new sawmill in Domat/Ems new opportunities are offered to the canton for more intensive use of the raw material, wood. This depends on a reduction in production costs and a positive attitude of the population towards the greater use of wood. A series of measures from the Grisons Forestry Department should be of help here. The risk of damage to infrastructure is particularly high in a mountainous canton. The cantonal government of the Grisons has commissioned the Forestry Department to define the situation concerning the possible consequences of global warming on natural hazards and to propose measures which may be taken. The setting up of extensive measurement and information systems, the elaboration of intervention maps, the estimation of the danger potential in exposed areas outside the building zone and the maintenance of existing protective constructions through the creation of a protective constructions register, all form part of the government programme for 2009 to 2012. In the Grisons, forest owners and visitors will have to become accustomed to the fact that their forests must again produce more wood and that, on account of global warming, protective forests will become even more important than they already are today.


2021 ◽  
pp. 6-16
Author(s):  
Judith  Dekker ◽  
Isabelle Hooijer ◽  
Johannes C.F. Ket ◽  
Aleksandra Vejnović ◽  
Giuseppe Benagiano ◽  
...  

<b><i>Objective:</i></b> Based on the hypothesis that neonatal uterine bleedings (NUB), occurring mostly in the first week after birth, could represent a pathogenetic mechanism for early-onset endometriosis, this systematic review (SR) was undertaken to evaluate the prevalence and screening strategies used to assess and quantify NUB. <b><i>Design:</i></b> Both a SR and a sample literature search in PubMed and Embase were conducted to gather information on NUB prevalence and screening techniques. This was performed by an information specialist. Only full-text articles regarding the assessment of NUB in neonates in the first 2 weeks after birth were included. No limit on language or publication data was used. <b><i>Materials and Methods:</i></b> The SR was registered in PROSPERO (CRD42019138121). Data was first assessed for eligibility on title and abstract by 2 blinded review authors. Any disagreements were discussed with a third reviewer if necessary. Subsequently, full-text articles were read and assessed for quality using the Cochrane Collaboration Handbook. <b><i>Results:</i></b> Out of 1,988 articles in the systematic search, 10 relevant articles were selected, of which 8 were identified through the systematic search and 2 were found through other sources. The sample search of 4,445 articles did not bring up relevant articles. Results were not comparable due to the heterogeneity of screening techniques, although data showed consensus. The prevalence of visible bleeding ranged from 3.3 to 53.8% and the prevalence of occult bleeding from 25.4 to 96.7%. The occurrence was the highest between the 3rd and 7th day postpartum (PP) and the bleeding lasted for 3–4 days on average. Various screening techniques for detecting NUB were found in the literature, including the use of hemoglobin detection devices (such as Hemastix) in the vaginal vestibulum, comparison of diapers with stains of known volume, colposcopy, and ultrasonography. <b><i>Conclusion:</i></b> The reported prevalence of NUB varies considerably, with a consistent occurrence between the 3rd and the 7th day PP. Literature to assess NUB is dated. The techniques are poorly described and heterogeneous. Future research should focus on prospective cohort studies in order to attempt to correlate NUB cases to (early-onset) endometriosis.


Author(s):  
Roland A. Snijder ◽  
Maurits K. Konings ◽  
Peter Lucas ◽  
Toine C. Egberts ◽  
Annemoon D. Timmerman

AbstractInfusion therapy is medically and technically challenging and frequently associated with medical errors. When administering pharmaceuticals by means of infusion, dosing errors can occur due to flow rate variability. These dosing errors may lead to adverse effects. We aimed to systematically review the available biomedical literature for


2014 ◽  
Vol 99 (2) ◽  
pp. 112-119 ◽  
Author(s):  
Zhi-jie Cong ◽  
Liang-hao Hu ◽  
Jun-jie Xing ◽  
Zheng-qian Bian ◽  
Chuan-gang Fu ◽  
...  

Abstract Anastomotic dehiscence (AD) requiring reoperation is the most severe complication following anterior rectal resection. We performed a systematic review on studies that describe AD requiring reoperation and its subsequent mortality after anterior resection for rectal carcinoma. A systematic search was performed on published literature. Data on the definition and rate of AD, the number of ADs requiring reoperation, the mortality caused by AD, and the overall postoperative mortality were pooled and analyzed. A total of 39 studies with 24,232 patients were analyzed. The studies varied in incidence and definition of AD. Systematic review of the data showed that the overall rate of AD was 8.6%, and the rate of AD requiring reoperation was 5.4%. The postoperative mortality caused by AD was 0.4%, and the overall postoperative mortality was 1.3%. We found considerable risk and mortality for AD requiring reoperation, which largely contributed to the overall postoperative mortality.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Wenxin Niu ◽  
Tienan Feng ◽  
Chenghua Jiang ◽  
Ming Zhang

Objectives. (1) To systematically review peak vertical ground reaction force (PvGRF) during two-leg drop landing from specific drop height (DH), (2) to construct a mathematical model describing correlations between PvGRF and DH, and (3) to analyze the effects of some factors on the pooled PvGRF regardless of DH.Methods. A computerized bibliographical search was conducted to extract PvGRF data on a single foot when participants landed with both feet from various DHs. An innovative mathematical model was constructed to analyze effects of gender, landing type, shoes, ankle stabilizers, surface stiffness and sample frequency on PvGRF based on the pooled data.Results. Pooled PvGRF and DH data of 26 articles showed that the square root function fits their relationship well. An experimental validation was also done on the regression equation for the medicum frequency. The PvGRF was not significantly affected by surface stiffness, but was significantly higher in men than women, the platform than suspended landing, the barefoot than shod condition, and ankle stabilizer than control condition, and higher than lower frequencies.Conclusions. The PvGRF and root DH showed a linear relationship. The mathematical modeling method with systematic review is helpful to analyze the influence factors during landing movement without considering DH.


2015 ◽  
Vol 14 (2) ◽  
pp. 90 ◽  
Author(s):  
K. L. M. Dos Passos ◽  
B. M. Viegas ◽  
E. N. Macêdo ◽  
J. A. S. Souza ◽  
E. M. Magalhães

The use of the waste of the Bayer process, red mud, is due to its chemical and mineralogical composition that shows a material rich in oxides of iron, titanium and aluminum. Some studies conducted show that this waste can be applied as a source of alternative raw material for concentration and subsequent recovery of titanium compounds from an iron leaching process, which is present in higher amounts, about 30% by weight. To obtain a greater understanding about the leaching kinetics, the information of the kinetic data of this process is very important. In this context, the main objective of this work is the development of a mathematical model that is able to fit the experimental data (conversion / extraction iron, titanium and aluminum) of the leaching process by which is possible to obtain the main kinetic parameters such as the activation energy and the velocity of chemical reactions as well as the controlling step of the process. The development of the mathematical model was based on the model of core decreasing. The obtained model system of ordinary differential equations was able to fit the experimental data obtained from the leaching process, enabling the determination of the controlling step, the rate constants and the activation energies of the leaching process.


2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Syahrul Muharamsyah ◽  
M Sofwan Anwari ◽  
Hafiz Ardian

Mangrove forests are unique ecosystems that have ecological, biological and socio-economic functions. The function of mangrove forests on the environment is very important especially in the coastal and oceanic regions. Mangrove forests providers of wood, leaves as raw material for medicines, and natural dye. This study aims to inventory the diversity of species of mangrove vegetation in Mendalok Village, Sungai Kunyit Subdistrict, Mempawah Regency. The benefits of this study are to provide the data on mangrove forest vegetation as basic data for local government and related agencies in efforts to protect and preserve mangrove forests in Mendalok Village, Sungai Kunyit Subdistrict, Mempawah Regency. Inventory the tree in mangrove forest used a line with measured 200 meters. There are 6 lines and the distance between the lines as far as 100 meters. The lines of observation are placed by purposive sampling. The results of research found 11 types of species and consisted of 6 genera. The genera are Avicennia, Bruguiera, Ceriops, Rhizophora, Soneratia and Xylocarpus. The species found were Avicennia alba, Avicennia marina, Bruguiera cylindrica, Bruguiera gymnorrhiza, Bruguiera parviflora, Ceriops decandra, Rhizophora apiculata, Rhizophora mucronata, Rhizophora stylosa, Sonneratia caseolaris, Xylocarpus mollucensis. Diversity of mangrove species in Mendalok Village, Sungai Kunyit Subdistrict, Mempawah Regency was high and should be maintained for conservation and ecotourism area. Keywords : conservation, ecotourism, mangrove, Mendalok Village


Author(s):  
S. G. Cherny ◽  
A. A. Zhilenkov

The study focuses on the modeled processes describing the interaction of the scanning sensor with the element of underwater communication. This task is relevant in constructing the systems for automated monitoring of underwater objects by means of unmanned underwater vehicles. A simple model has been obtained that makes it possible to describe the structural properties of the object’s material or damage on its surface. The mathematical model of interaction between the object and the scanning sensor is presented as a sum of two series. The study shows that in problems of controlling the local structure of the object’s surface, it is possible to present the mathematical model in Kotelnikov expanded form. The obtained results are of high practical importance in solving the problems of laying specialized lines and highways in the territory of the Crimean water area of the Azov-Black Sea basin and regular monitoring their condition


2019 ◽  
Vol 17 (2) ◽  
pp. 87-99
Author(s):  
Gerd Brantes Angelkorte

The concern with global warming impacts on the environment has made the world population search for new energy sources that are less aggressive to the environment. Therefore, biodiesel has become more relevant and has expanded its proportion in the blend with diesel. However, Brazil still uses about 20% of bovine tallow, which emits large amount of GHG, degrades the soil and entails great water consumption. The purpose of this study was to evaluate the possibilities and effects of the substitution of this nonrenewable source for others of vegetable origin, as well as the environmental effects of increasing the percentage of biodiesel, reaching levels of 20% and 30%. Hence, two types of biodiesel were produced and tested, with and without bovine tallow, and the results obtained and data from the diesel fleet were used to model the impacts and CO2eq emissions with the aid of the MoMo Lite model in Brazil. It was possible to determine the great benefit of adopting higher levels of biodiesel in diesel (especially when there was a substitution of bovine tallow for plant sources), besides the importance of adopting broader analysis of the whole production cycle of the raw material. Since only CO2eq emission data were observed at the burning, the results varied only 10%, but when the results were analyzed through the well-to-tank, this variation rose to 52%.


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