scholarly journals Indicator of tension in the living space of protective forest stands

2020 ◽  
Vol 11 (4) ◽  
Author(s):  
V. M. Maliuha ◽  
V. V. Minder
Keyword(s):  
Self Regulation ◽  
Significant Loss ◽  
Average Height ◽  
Forest Stands ◽  
Scotch Pine ◽  
Cross Sectional ◽  
High Productivity ◽  
Living Space ◽  
Growing Conditions ◽  
The Stability

The density of stands remains a controversial issue to this day, requiring a practical solution in terms of the optimal liquefaction of plantings without a significant loss of the quantitative productivity of the trunk stock of wood and the stability of forest stands. Only as a result of focused efforts can the patterns of natural liquefaction or the process of self-regulation of complex biological systems, to which the forest belong, be achieved. Natural liquefaction of forest stands is an extremely complex process due to its multifactorial nature, to the manifestation of which climatic, soil, biological conditions and many other mutual influences are involved. In forest biogeocenoses, the edifacatory role belongs to the main stand. This tier represents a group of tree species in a phytocenosis, which determines its structure and, to a certain extent, composition. In this study, it is proposed to evaluate the functional load by an indicator of the tension of the living space of the plantation. Since Scotch pine is one of the most common edificators, widely used in the creation of anti-erosion plantations on soils of varying degrees of washout, substantiation of the indicator of tension is carried out on its example. The formula for calculating the tension indicator of the living space, characterizing the growing conditions of the plantation, is given. The indicator of the tension of living space is the ratio of the average height of plantings to their absolute completeness. The verification of the proposed indicator was carried out using tables of the course of growth, highlighting the patterns of the structure of tree stands. A graphic interpretation of the static research of forest stands is carried out. If the values of the tension indicators coincide with the distribution curve obtained from the standard tables of the sum of the cross-sectional areas of tree trunks with a completeness of 1.0, this indicates the optimal use of living space by plantations. The values of the indicators placed above the curve indicate the intensive use of living space. If the values of the indicators are located under the curve - it is incomplete use of living space. Since there is continuous forest management in Ukraine, and for timely forestry measures, it is necessary to constantly monitor the state of plantations. For successful cultivation of anti-erosion plantings of sufficiently high productivity and convenience of monitoring their condition, the proposed indicator can be used.

scholarly journals Long-term experiment on the effect of thinnings in the upland artificial stands of quercus robur in the southern forest-steppe

2018 ◽  
Vol 7 (4) ◽  
pp. 72-81
Author(s):  
Яна Истомина ◽  
Yana Istomina ◽  
Наталья Каплина ◽  
Natalia Kaplina
Keyword(s):  
Forest Steppe ◽  
Average Height ◽  
Cross Sectional ◽  
Relative Increment ◽  
Long Term Experiment ◽  
English Oak ◽  
Total Productivity ◽  
The Stability ◽  
Academy Of Sciences

The results of a 60-year experience on the effect of thinning on the stability and productivity of the stand of English oak of artificial origin in the Tellerman experimental forestry of the Institute of Forestry of the Russian Academy of Sciences have been summed up. Cleaning cuttings was carried out on permanent trial plots in 2 ways - by the grassroots method and by method of V.G. Nesterov with an intensity of up to 35% in stock 3 times. In the long-term dynamics, the ranking of stands on the average height and diameter, the number of trunks and the sum of cross-sectional areas, stock and total productivity, given by the intensity and the method of thinning, was mainly preserved. With increasing felling intensity, regardless of their method, relative increment and change in the stock have increased. In conditions of periodic moisture deficiency and accompanying damage to the leaves by insects, the stands could not restore previous trajectory of stock after the third felling. After 60 years of age, the stock of forest stands has not practically increased. Regardless of the intensity and the method, cleaning cutting contributed to the stability of growth rate of the stands. In the control, the stock decreased as a result of wave detachment, including large trunks. The stock of large trunks by the age of 80 years in the options with cutting was higher than in control one by an average of 17%. In order to reduce the risk of stock reduction by the age of ripeness in the upland oak forests of the southern forest-steppe, it is recommended to limit the period of intensive cutting up to 40 years. In this case, the trees will be able to form well-developed crowns at the end of the period of rapid growth. During unfavorable periods there is a decrease in the productivity of plantations and a decrease in the effect of thinning, which is important to take into account when predicting the growth of stands.

Respiratory Sinus Arrhythmia During Sleep and Waking

2019 ◽  
Vol 33 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Elizabeth M. Stoakley ◽  
Karen J. Mathewson ◽  
Louis A. Schmidt ◽  
Kimberly A. Cote
Keyword(s):  
Individual Differences ◽  
Respiratory Sinus Arrhythmia ◽  
Slow Wave Sleep ◽  
Self Regulation ◽  
Nrem Sleep ◽  
Sinus Arrhythmia ◽  
Affective Style ◽  
Waking State ◽  
Optimal Period ◽  
The Stability

Abstract. Resting respiratory sinus arrhythmia (RSA) is related to individual differences in waking affective style and self-regulation. However, little is known about the stability of RSA between sleep/wake stages or the relations between RSA during sleep and waking affective style. We examined resting RSA in 25 healthy undergraduates during the waking state and one night of sleep. Stability of cardiac variables across sleep/wake states was highly reliable within participants. As predicted, greater approach behavior and lower impulsivity were associated with higher RSA; these relations were evident in early night Non-REM (NREM) sleep, particularly in slow wave sleep (SWS). The current research extends previous findings by establishing stability of RSA within individuals between wake and sleep states, and by identifying SWS as an optimal period of measurement for relations between waking affective style and RSA.

Effect of Four Training Systems on Growth and Productivity of `Cortland'/M.9 EMLA Apple Trees

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 451e-451
Author(s):  
J.R. Schupp ◽  
S.I. Koller
Keyword(s):  
Fruit Size ◽  
Vertical Axis ◽  
Significant Loss ◽  
Training Methods ◽  
Cumulative Yield ◽  
Or Efficiency ◽  
Cross Sectional ◽  
Tree Survival ◽  
Canopy Volume ◽  
Planting Distance

`Cortland'/M.9 EMLA trees were planted in 1991 at 1.8 ×4.2-m spacing. The trees were trained to one of four systems: 1) Vertical Axis; 2) Y trellis; 3) Solen; or 4) Palmette trellis. Tree survival was 86% for Palmette trees and approached 100% for the other three systems. Annual yield and cumulative yield per tree of Vertical Axis and Y trellis was twice that of Solen or Palmette. Tree vigor was sub-optimal relative to planting distance in this study. Trunk cross-sectional area of Vertical Axis trees was larger than that of trees trained to Solen or Palmette, while trees trained to Y trellis were intermediate in trunk growth. Canopy volumes of Vertical Axis and Y trellis trees were similar, and greater than that of Solen or Palmette trees. Fruit size on Solen and Palmette trees was larger than that of Y trellis trees in 1995 and 1996, while fruit size on Vertical Axis trees was intermediate. Cumulative yield per cubic meter of canopy volume was the same for all four systems, suggesting that differences in productivity among systems were attributable to the effects of tree training practices on tree size, not to differences among systems in precocity or efficiency. The low heading cut needed to establish the lowest tier of branches on the Palmette system reduced tree vigor and in some cases, resulted in mortality. The horizontal training of the primary branches of the Solen severely reduced tree vigor. In this study, where tree vigor was sub-optimal due to rootstock selection, the additional restrictions in tree growth resulting from restrictive training methods resulted in a significant loss in productivity.

scholarly journals Meaningful activities during COVID-19 lockdown and association with mental health in Belgian adults

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Cruyt Ellen ◽  
De Vriendt Patricia ◽  
De Letter Miet ◽  
Vlerick Peter ◽  
Calders Patrick ◽  
...  
Keyword(s):  
Mental Health ◽  
General Health Questionnaire ◽  
Health Condition ◽  
Daily Activities ◽  
The Internet ◽  
Cross Sectional ◽  
Daily Lives ◽  
Living Space ◽  
Resilience Scale

Abstract Background The spread of COVID-19 has affected people’s daily lives, and the lockdown may have led to a disruption of daily activities and a decrease of people’s mental health. Aim To identify correlates of adults’ mental health during the COVID-19 lockdown in Belgium and to assess the role of meaningful activities in particular. Methods A cross-sectional web survey for assessing mental health (General Health Questionnaire), resilience (Connor-Davidson Resilience Scale), meaning in activities (Engagement in Meaningful Activities Survey), and demographics was conducted during the first Belgian lockdown between April 24 and May 4, 2020. The lockdown consisted of closing schools, non-essential shops, and recreational settings, employees worked from home or were technically unemployed, and it was forbidden to undertake social activities. Every adult who had access to the internet and lived in Belgium could participate in the survey; respondents were recruited online through social media and e-mails. Hierarchical linear regression was used to identify key correlates. Results Participants (N = 1781) reported low mental health (M = 14.85/36). In total, 42.4% of the variance in mental health could be explained by variables such as gender, having children, living space, marital status, health condition, and resilience (β = −.33). Loss of meaningful activities was strongly related to mental health (β = −.36) and explained 9% incremental variance (R2 change = .092, p < .001) above control variables. Conclusions The extent of performing meaningful activities during the COVID-19 lockdown in Belgium was positively related to adults’ mental health. Insights from this study can be taken into account during future lockdown measures in case of pandemics.

scholarly journals The mediating role of narcissism in the effects of regulatory mode on positivity

2021 ◽  
Author(s):  
Daniela Di Santo ◽  
Calogero Lo Destro ◽  
Conrad Baldner ◽  
Alessandra Talamo ◽  
Cristina Cabras ◽  
...  
Keyword(s):  
Self Regulation ◽  
Well Being ◽  
Cross Sectional Study ◽  
Motivational Orientation ◽  
Cross Sectional ◽  
Mediating Role ◽  
Regulatory Mode ◽  
The Individual ◽  
Reported Data

AbstractPositivity (i.e., the individual tendency to positively approach life experiences) has proven to be an effective construct applied in positive psychology. However, individuals’ self-regulation may have contrasting effects on positivity. We specifically examined whether positivity could be partially explained through two aspects of motivation concerned with self-regulation: locomotion (i.e., a motivational orientation concerned with movement) and assessment (i.e., a motivational orientation concerned with comparison and evaluation). Furthermore, based on previous literature that found a link between these aspects and narcissism, we examined whether “adaptive” and “maladaptive” dimensions of narcissism could mediate the effects of locomotion and assessment on increased or decreased positivity. Narcissism was defined by previous research as adaptive or maladaptive insofar as it leads or does not lead to increased psychological well-being. We estimated a mediation model with multiple independent variables and multiple mediators in a cross-sectional study with self-reported data from 190 university students. We found that both locomotion and assessment were associated with adaptive narcissism, which in turn was positively associated with positivity. However, assessment was also associated with maladaptive narcissism, which in turn was negatively associated with positivity. Relationships between aspects of self-regulation, narcissism, and positivity can have significant implications which will be discussed.

ANTIBIOTIC STABILITY IN SOLUTIONS USED FOR INTRAVENOUS NUTRITION AND FLUID THERAPY

PEDIATRICS ◽  
1973 ◽  
Vol 51 (6) ◽  
pp. 1016-1026
Author(s):  
Ralph D. Feigin ◽  
Kanneth S. Moss ◽  
Penelope G. Shackelford
Keyword(s):  
Antimicrobial Activity ◽  
Normal Saline ◽  
Protein Hydrolysate ◽  
Significant Degree ◽  
Significant Loss ◽  
All Solutions ◽  
Ringer’S Lactate ◽  
Series Of Experiments ◽  
The Stability ◽  
Crystalline Amino Acids

The present study was designed to assess the stability of ampicillin, carbenicillin, clindamycin, kanamycin, cephalothin, methicillin, and penicillin in three parenteral hyperalimentation mixtures as reconstituted for delivery to the patient in the clinical setting. Stability at 4C, 25C, and 37C was tested in parenteral hyperalimentation mixtures containing either crystalline amino acids or a protein hydrolysate. In two series of experiments the stability at 4C, 25C, and 37C of ampicillin, cephalothin, and kanamycin also was assessed in Isolyte M (ISO M), Isolyte P (ISO P), Ringer's lactate (LR), 5% dextrose in water, (D5W), 10% dextrose in water (D1OW), dextrose in normal saline (D5S), and normal saline (NS) to which hydrocortisone or heparin had been added. All antibiotics retained their effectiveness at an acceptable level in the hyperalimentation solutions at 4C. At 25C and 37C, all antibiotics except clindamycin lost activity by 24 hours. Kanamycin was least stable in these solutions and ampicillin also lost a significant degree of antimicrobial activity. Addition of heparin or hydrocortisone imparted stability to ampicillin in the seven parenteral solutions although significant loss of activity was noted at 37C in D5W, D1OW, D5S, and LR. Most solutions containing heparin or hydrocortisone and cephalothin turned yellow by 24 hours. A precipitate appeared in solutions containing heparin and kanamycin but there was minimal loss of antimicrobial activity. Kanamycin was stable in all solutions containing hydrocortisone except in D5W and D10W at 37C.

A survey of YouTube videos as a source of useful/un-useful information in the field of the prevention and management of burn injuries: A cross-sectional analysis of the English language content

2021 ◽  
Author(s):  
Kayhan Gurbuz ◽  
Mete Demir ◽  
Koray Das
Keyword(s):  
English Language ◽  
Burn Injury ◽  
Significant Loss ◽  
Burn Injuries ◽  
Cross Sectional ◽  
Global Quality ◽  
Content Ratio ◽  
Media Platform ◽  
Youtube Videos

Abstract The study was designed on whether YouTube videos are useful as an information resource in the field of burn injury prevention and management. Current literature on the educational content and quality of burn-related first aid videos on YouTube was reported as inadequate and inaccurate. However, the quality of YouTube videos on various medical and clinical topics has been the subject of many previous studies, and there has been increasing evidence that the content ratio of usefulness was higher than that of non-useful. While hours and even minutes in burn injuries are as precious as gold in terms of outcomes, it would be a significant loss not to use the most popular and easily accessible free social media platform of our time as a tool that can contribute to the prevention of burns and raise awareness. Analysis was conducted with the remaining 96 videos from 240 videos obtained from YouTube, according to possible search terms and exclusion of videos according to predetermined criteria. The Global Quality Score (GQS) and modified DISCERN (m.DISCERN) tools were used to assess the quality and reliability of the videos. Viewer engagement metrics and video properties were also investigated according to the usefulness criteria (e.g., video length, duration on YouTube, topic contents, source uploads, reliability, and quality). Finally, it was revealed that nearly 80 percent of the YouTube videos contained information in the field of the prevention and management of burn injuries deemed useful in this study, comparable to the other medical disciplines' reports in the literature.

scholarly journals Low back pain in physiotherapy students: Prevalence and the association with neuromuscular findings

2013 ◽  
Vol 69 (4) ◽  
Author(s):  
E. Burger ◽  
H. Myezwa ◽  
V. Naidoo ◽  
B. Olivier ◽  
A. Rothberg
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Cross Sectional Study ◽  
Transversus Abdominis ◽  
Low Back ◽  
Cross Sectional ◽  
Active Involvement ◽  
Optimal Function ◽  
The Stability ◽  
Physiotherapy Students

Background: Physiotherapy students are prone to low back pain (LBP) due to studying and their active involvement in clinical treatment of patients. As a result of pathology, muscle activity is influenced, affecting optimal function of the spine. Method: Physiotherapy students enrolled for 2010 at the University of the Witwatersrand participated in a cross-sectional study. A questionnaire and physical assessment were completed. Results: The study revealed that the lifetime LBP prevalence was 36% among physiotherapy students. Associations with LBP were hours of practical exposure, posterior-anterior mobilisations on L4 (p=0.003) and L5 (p≤0.001) centrally and unilaterally, left lumbar multifidus (LM) cross-sectional area (p=0.02), right obliquus internusabdominis (OI) (p=0.02) and right transversus abdominis (TrA) thickness at rest (p=0.02), as well as the pull of the TrA during contraction on the left (p=0.03). Discussion: Hours of practical exposure may play a role in lumbar pathology. Due to pathology, muscle imbalances of LM, TrA and OI affect the stability of the spine which may lead to recurrences. Conclusion: Practical exposure as well as LM, TrA and OI muscle imbalances were associated with LBP in physiotherapy students. Awareness of the factors associated with LBP while studying at an undergraduate level may lead to better prevention of LBP.

scholarly journals Glacial lake drainage: a stability analysis

1997 ◽  
Vol 24 ◽  
pp. 175-180
Author(s):  
Krzysztof Szilder ◽  
Edward P. Lozowski ◽  
Martin J. Sharp
Keyword(s):  
Differential Equations ◽  
Water Flow ◽  
Frictional Heating ◽  
Initial Perturbation ◽  
Tunnel Wall ◽  
Cross Sectional ◽  
Linear Ordinary Differential Equations ◽  
Simplifying Assumptions ◽  
Lake Drainage ◽  
The Stability

A model has been formulated to determine the stability regimes for water flow in a Subglacial conduit draining from a reservoir. The physics of the water flow is described with a set of differential equations expressing conservation of mass, momentum and energy. Non-steady flow of water in the conduit is considered, the conduit being simultaneously enlarged by frictional heating and compressed by plastic deformation in response to the pressure difference across the tunnel wall. With the aid of simplifying assumptions, a mathematical model has been constructed from two time-dependent, non-linear, ordinary differential equations, which describe the time evolution of the conduit cross-sectional area and the water depth in the reservoir. The model has been used to study the influence of conduit area and reservoir levels on the stability of the water flow for various glacier and ice-sheet configurations. The region of the parameter space where the system can achieve equilibrium has been identified. However, in the majority of cases the equilibrium is unstable, and an initial perturbation from equilibrium may lead to a catastrophic outburst of water which empties the reservoir.

scholarly journals Scale of adverse events associated to nursing practices: a psychometric study in Portuguese hospital context

2018 ◽  
Vol 26 ◽  
Author(s):  
Teresa Neves ◽  
Vitor Rodrigues ◽  
João Graveto ◽  
Pedro Parreira
Keyword(s):  
Adverse Events ◽  
Public Hospital ◽  
Hospital Setting ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Stable Factor ◽  
Hospital Units ◽  
Northern Regions ◽  
Structural Invariance ◽  
The Stability

Objective to contribute to the validation study of the Scale of Adverse Events associated with Nursing Practices in the hospital context. Method cross-sectional study, in public hospital units, in the central and northern regions of Portugal. The exploratory factor analysis of the Scale of Adverse Events associated to Nursing Practices was conducted with a sample of 165 nurses and the confirmatory factorial analysis was made with a sample of 685 nurses. Reliability, internal consistency and construct validity were estimated. The invariance of the model was evaluated in two subsamples to confirm the stability of the factorial solution. Results the global sample consisted of 850 nurses aged between 22 and 59, mostly licensed professionals. The model had a good overall fit in the subscales (Nursing Practices: χ2/df = 2.88, CFI = 0.90, GFI = 0.86, RMSEA = 0.05, MECVI = 3.30; Adverse Events: χ2/df = 4.62, CFI = 0.93, GFI = 0.95, RMSEA = 0.07, MECVI = 0.39). There was a stable factor structure, indicating strong invariance in the subscale Nursing Practices and structural invariance in the subscale Adverse Events. Conclusion the refined model of the Scale of Adverse Events associated with Nursing Practices revealed good fit and stability of the factorial solution. The instrument was adjusted to evaluate the perception of nurses about adverse events associated with health care, precisely nursing care, in the hospital setting.

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