scholarly journals The Accessibility of Post-Fire Areas for Mechanized Thinning Operations

Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 471
Author(s):  
Dariusz Kulak ◽  
Janusz M. Sowa ◽  
Grzegorz Szewczyk ◽  
Arkadiusz Stańczykiewicz
Keyword(s):  
Bearing Capacity ◽  
Forest Fire ◽  
Soil Compaction ◽  
Fire History ◽  
Timber Harvesting ◽  
Average Value ◽  
Penetrometer Resistance ◽  
History Of ◽  
Thinning Operations ◽  
And Control

In 1992, in Southern Poland, large areas of Silesian forests were affected by the country’s largest forest fire. Stands introduced in the 9000-ha post-fire region are currently undergoing early thinning. Due to the scope of these treatments, the chance for their timely implementation is ensured only by the application of cut-to-length (CTL) technologies, i.e., with the use of harvesters and forwarders. The use of CTL technologies may, however, be difficult due to the fire history of these stands, which could affect the bearing capacity of their soils. The objective of this study is to determine the accessibility of stands for forest machines in relation to the bearing capacity of the soils and changes in soil compaction in the post-fire sites. Soil compaction was measured in terms of penetrometer resistance in the stands introduced in the post-fire area in question, as well as in control stands growing on five different soil types. It was shown that in the topsoil layer—from 8 to 18 cm thick depending on the soil type—differences in soil compaction in the post-fire and control areas were relatively small. The impacts of the forest fire—manifested as a significant increase in the compaction of the forest soils—were still visible, but only in the deeper layers of the soil profile. In all of the compared pairs of forest compartments located in the stands regenerated after the fire, significantly higher values of cone indexes (CI) were found. The average value of this index in the post-fire stands was 2.15 MPa, while in the control stands it was 1.60 MPa, which indicates that in both groups of stands the bearing capacity of the soils should not limit the accessibility for vehicles used for timber harvesting and extraction.

Forest fire history of Desolation Peak, Washington

1991 ◽  
Vol 21 (1) ◽  
pp. 83-83
Author(s):  
James K. Agee ◽  
Mark Finney ◽  
Roland de Gouvenain
Keyword(s):  
Forest Fire ◽  
Fire History ◽  
History Of

not available

scholarly journals COMPACTAÇÃO DE UM LATOSSOLO SUBMETIDO AO TRÁFEGO DE SKIDDER COM DIFERENTES RODADOS

FLORESTA ◽  
2011 ◽  
Vol 41 (3) ◽  
Author(s):  
Eduardo Da Silva Lopes ◽  
Jean Alberto Sampietro ◽  
André Leonardo Nasser Pereira ◽  
Diego de Oliveira
Keyword(s):  
Soil Compaction ◽  
Heavy Traffic ◽  
Total Porosity ◽  
Soil Bulk Density ◽  
Timber Harvesting ◽  
Soil Physical Properties ◽  
Penetrometer Resistance ◽  
Wood Extraction ◽  
Increase In Productivity

O processo de mecanização da colheita de madeira possibilitou um aumento significativo na produtividade e na qualidade das operações. Entretanto, o tráfego intenso de máquinas pesadas tem sido o grande responsável pela compactação do solo em áreas florestais. Este trabalho teve como principal objetivo avaliar os níveis de compactação de um Latossolo causada pelo trator florestal skidder com rodados de pneus e rodados de pneus recobertos com semiesteiras. O estudo foi conduzido nas áreas de colheita de madeira de uma empresa florestal localizada no estado do Paraná. A compactação do solo foi determinada por meio de alterações nas variáveis de densidade, porosidade total, porosidade de aeração e resistência do solo à penetração. As amostras de solo e os dados de resistência à penetração foram coletados em quatro pontos igualmente espaçados ao longo das trilhas de tráfego das máquinas e em linhas sem tráfego (testemunha), em três níveis de profundidade (0 a 15, 15 a 30 e 30 a 50 cm). A análise dos resultados mostrou que o skidder equipado com rodados de pneus foi responsável pela maior alteração na densidade do solo, com 1,22 e 1,17 mg.m-3 nas profundidade de 0 a 15 e 15 a 30 cm, respectivamente. Não houve alteração significativa nas propriedades físicas do solo devido ao tráfego do skidder com os diferentes tipos de rodados, mostrando que a instalação da semiesteira nos rodados das máquinas não acarretou em redução da compactação do solo.Palavras-chave: Compactação; tipos de rodados; extração florestal. AbstractCompaction of a latosol subjected to skidder traffic with different wheeled. The process of mechanization of timber harvesting allowed a significant increase in productivity and quality of operations. However, heavy traffic of large machines has been largely responsible for soil compaction in forest areas.This research aimed to evaluate the latosol compaction caused by skidder with tires and tracks over the tires. The study was developed in the logging areas of a forestry company located in Parana State. Soil compaction was evaluated by soil bulk density, aeration porosity, total porosity and penetrometer resistance. The soil samples and date of penetrometer resistance were taken at four points equally spaced along both the trails with and without traffic at three depth levels (0 to 15, 15 to 30 and 30 to 50 cm). The results showed that the skidder equipped with tires was responsible for the greatest change in density, with 1.22 and 1.17 mg.m-3 in the depth of 0 to 15 and 15 to 30 cm, respectively. There was not significant change in soil physical properties caused by skidder traffic with the different wheeled types, proving that the installation of the tracks over tires did not result in smaller soil compaction.Keywords: Compaction; wheeled types; wood extraction.

scholarly journals The first forest fire history of the Burabai Region (Kazakhstan)from tree rings of Pinus sylvestris

2017 ◽  
Vol 41 ◽  
pp. 165-174 ◽  
Author(s):  
Kuralay MAZARZHANOVA ◽  
Arailym KOPABAYEVA ◽  
Nesibe KÖSE ◽  
Ünal AKKEMİK
Keyword(s):  
Pinus Sylvestris ◽  
Tree Rings ◽  
Forest Fire ◽  
Fire History ◽  
History Of

THE RISK FACTORS OF MOLAR PREGNANCY

2017 ◽  
pp. 53-58
Author(s):  
Lam Huong Le
Keyword(s):  
High Risk ◽  
Gestational Trophoblastic Disease ◽  
Living Standard ◽  
Control Group ◽  
Uterine Perforation ◽  
Molar Pregnancy ◽  
Health It ◽  
Pregnancy Risk ◽  
History Of ◽  
And Control

Objectives: Molar pregnancy is the gestational trophoblastic disease and impact on the women’s health. It has several complications such as toxicity, infection, bleeding. Molar pregnancy also has high risk of choriocarcinoma which can be dead. Aim: To assess the risks of molar pregnancy. Materials and Methods: The case control study included 76 molar pregnancies and 228 pregnancies in control group at Hue Central Hospital. Results: The average age was 32.7 ± 6.7, the miximum age was 17 years old and the maximum was 46 years old. The history of abortion, miscarriage in molar group and control group acounted for 10.5% and 3.9% respectively, with the risk was higher 2.8 times; 95% CI = 1.1-7.7 (p<0.05). The history of molar pregnancy in molar pregnancy group was 9.2% and the molar pregnancy risk was 11.4 times higher than control group (95% CI = 2.3-56.4). The women having ≥ 4 times births accounted for 7.9% in molar group and 2.2% in control group, with the risk was higher 3.8 times, 95% CI= 1.1-12.9 (p<0.05). The molar risk of women < 20 and >40 years old in molar groups had 2.4 times higher than (95% CI = 1.1 to 5.2)h than control group. Low living standard was 7.9% in molar group and 1.3% in the control group with OR= 6.2; 95% CI= 1.5-25.6. Curettage twice accounted for 87.5%, there were 16 case need to curettage three times. There was no case of uterine perforation and infection after curettage. Conclusion: The high risk molar pregnancy women need a better management. Pregnant women should be antenatal cared regularly to dectect early molar pregnancy. It is nessecery to monitor and avoid the dangerous complications occuring during the pregnancy. Key words: Molar pregnancy, pregnancy women

Work and Technological Change

2020 ◽  
Author(s):  
Stephen R. Barley
Keyword(s):  
Artificial Intelligence ◽  
Historical Context ◽  
Energy Transformation ◽  
History Of ◽  
Work And Organizations ◽  
Role Based ◽  
Control Technologies ◽  
And Control ◽  
Work And Employment

The four chapters of this book summarize the results of thirty-five years dedicated to studying how technologies change work and organizations. The first chapter places current developments in artificial intelligence into the historical context of previous technological revolutions by drawing on William Faunce’s argument that the history of technology is one of progressive automation of the four components of any production system: energy, transformation, and transfer and control technologies. The second chapter lays out a role-based theory of how technologies occasion changes in organizations. The third chapter tackles the issue of how to conceptualize a more thorough approach to assessing how intelligent technologies, such as artificial intelligence, can shape work and employment. The fourth chapter discusses what has been learned over the years about the fears that arise when one sets out to study technical work and technical workers and methods for controlling those fears.

Galileo Unbound

2018 ◽  
Author(s):  
David D. Nolte
Keyword(s):  
Free Fall ◽  
The Sun ◽  
Quantum Field ◽  
Many Worlds ◽  
Quantum Particles ◽  
Light Rays ◽  
History Of ◽  
And Control ◽  
The Universe ◽  
Insight Into

Galileo Unbound: A Path Across Life, The Universe and Everything traces the journey that brought us from Galileo’s law of free fall to today’s geneticists measuring evolutionary drift, entangled quantum particles moving among many worlds, and our lives as trajectories traversing a health space with thousands of dimensions. Remarkably, common themes persist that predict the evolution of species as readily as the orbits of planets or the collapse of stars into black holes. This book tells the history of spaces of expanding dimension and increasing abstraction and how they continue today to give new insight into the physics of complex systems. Galileo published the first modern law of motion, the Law of Fall, that was ideal and simple, laying the foundation upon which Newton built the first theory of dynamics. Early in the twentieth century, geometry became the cause of motion rather than the result when Einstein envisioned the fabric of space-time warped by mass and energy, forcing light rays to bend past the Sun. Possibly more radical was Feynman’s dilemma of quantum particles taking all paths at once—setting the stage for the modern fields of quantum field theory and quantum computing. Yet as concepts of motion have evolved, one thing has remained constant, the need to track ever more complex changes and to capture their essence, to find patterns in the chaos as we try to predict and control our world.

Animal Pain Scales in Public Policy

1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 41-50
Author(s):  
F. Barbara Orlans
Keyword(s):  
Public Policy ◽  
Animal Welfare ◽  
The United States ◽  
Pain Scale ◽  
Laboratory Animals ◽  
Practical Applications ◽  
Animal Pain ◽  
Pain Scales ◽  
History Of ◽  
And Control

Pain scales classify the severity of pain inflicted on laboratory animals from little or none up to severe. A pain scale as part of public policy serves beneficial purposes that promote animal welfare. It can be used to educate people about the two alternatives of refinement and replacement, and the need to reduce animal pain. Furthermore, a pain scale has practical applications: 1) in review procedures for animal welfare concerns; 2) in developing policies on the use of animals in education; and 3) as a basis for collecting national data on animal experimentation, so that meaningful data can be collected on trends in reduction and control in animal pain. So far, only a few countries (including Sweden, the Netherlands, Canada and New Zealand) have adopted pain scales as part of their public policy. Most countries, including the United States, have not yet done so. The history of the development and adoption of pain scales by various countries is described and the case is presented for wider adoption of a pain scale in countries not currently using one.

scholarly journals Surveillance and control of M. chimaera infections in the Tuscany Region, Italy

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
B Casini ◽  
B Tuvo ◽  
M Totaro ◽  
A Baggiani ◽  
G Privitera
Keyword(s):  
Cardiac Surgery ◽  
Cardiopulmonary Bypass ◽  
Water Sample ◽  
Case Finding ◽  
Microbial Count ◽  
Clinical Specimens ◽  
Open Chest ◽  
Microbiological Parameters ◽  
History Of ◽  
And Control

Abstract Background Disseminated M. chimaera infections among patients who underwent open-chest surgery with cardiopulmonary bypass have been associated with the contamination of heater-cooler devices (HCDs). The Tuscany region in the Decree 3822/2019 issued recommendations for the surveillance and control of M. chimaera infections. Methods In three Tuscan cardiac surgery centers, the case finding was carried out through evaluation and testing of patients with a history of HCD exposure (past 6 years) was performed. Water and aerosol samples were analyzed from each HCDs to determine the microbiological parameters required by the Directive 98/83/CE and to assess the presence of non-tuberculous mycobacteria (NTMs), according to the regional protocol. Results M. chimaera infection was not found in any patient and all clinical specimens tested negative. 22 HCDs were sampled (n.12 LivaNova, n.1 Terumo and n.9 Maquet) for a total of 114 samples (45, 8, 2 and 59 respectively). All the microbiological parameters were compliant, excepted for total microbial count at 36 °C that exceeded 100 CFU/ml in 50% (57/114) of samples and for the presence of P.aeruginosa in 10% (12/114). NTMs were detected in 16% (18/114) of HCDs: M. chimaera was identified in 11% (13/114) of samples and in 4% (5/114) M. gordonae. All aerosol samples were negative for NTMs, but in the HCDs Maquet, B.cereus were detected in 7% (4/59) of the samples, K.oxytoca in 2% (1/59), B.ursincola in 2% (1/59) and S. paucimobilis in 3% (2/59). Only S. paucimobilis was isolated also in the same HCD water sample. Conclusions The implementation of maintenance and disinfection procedures of HCDs was able to reduce the risk of contamination and aerosolization by NTMs but not of other microorganisms. Key messages Further strategies should be put in place for the cases finding. Moreover, reliable decontamination and identification of agents that can disrupt biofilms and increase chlorine susceptibility of mycobacteria are required.

scholarly journals Cytotoxic Effects of N,N-Diethyl-Meta-Toluamide (DEET) on Sinonasal Epithelia

OTO Open ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 2473974X2110092
Author(s):  
Jivianne T. Lee ◽  
Saroj Basak
Keyword(s):  
Cell Viability ◽  
Chronic Rhinosinusitis ◽  
Morphological Changes ◽  
Environmental Toxicants ◽  
Cytotoxic Effects ◽  
Airborne Pollutants ◽  
Cell Monitoring ◽  
History Of ◽  
And Control ◽  
Dose Dependent

Although the etiology of chronic rhinosinusitis remains unknown, environmental factors including airborne pollutants and toxicants are postulated to contribute to its pathogenesis. However, the precise pathomechanisms with which environmental toxicants may contribute to chronic rhinosinusitis are not fully understood. The purpose of this pilot study is to examine the cytotoxic effects of N,N-diethyl- meta-toluamide (DEET), a commonly used pesticide, on sinonasal epithelial cells (SNECs). Sinus mucosa was obtained from 3 subjects without a history of chronic rhinosinusitis. Cultured SNECs were exposed to various concentrations of DEET (0-5 mM) for 6 days. Cell viability, proliferation, and morphologic changes were assessed using the MTT colorimetric dye assay and the Incucyte Live Cell Monitoring System. Statistically significant dose-dependent reduction in cell viability and proliferation was observed between exposure and control groups ( P < .05) at all concentrations tested. Dose-dependent cellular morphological changes were also seen. These findings indicate that DEET exposure induces dose-dependent cytotoxicity in sinonasal epithelia.

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