EARLYWOOD VESSELS IN RING-POROUS TREES BECOME FUNCTIONAL FOR WATER TRANSPORT AFTER BUD BURST AND BEFORE THE MATURATION OF THE CURRENT-YEAR LEAVES

IAWA Journal ◽  
2016 ◽  
Vol 37 (2) ◽  
pp. 315-331 ◽  
Author(s):  
Peter Kitin ◽  
Ryo Funada

This paper reviews the development of xylem vessels in ring-porous dicots and the corresponding leaf phenology. Also included are our original observations on the time-course of vessel element growth, secondary wall deposition, and end wall perforation in the deciduous hardwood Kalopanax septemlobus. Different patterns of xylem growth and phenology serve different strategies of the species for adaptation to seasonal climates. Trees with ring-porous xylem form wide earlywood vessels (EWV) in spring and narrow latewood vessels in summer. The wide EWV become embolized or blocked with tyloses by the end of the growing season while the narrow vessels may remain functional for many years. The co-occurrence of wide and narrow vessels provides both efficiency and safety of the water transport as well as a potentially longer growing season. It has for a long time been assumed that EWV in ring-porous hardwoods are formed in early spring before bud burst in order to supply sap to growing leaves and shoots.However, the full time-course of development of EWV elements from initiation of growth until maturation for water transport has not been adequately studied until recently. Our observations clarify a crucial relationship between leaf maturation and the maturation of earlywood vessels for sap transport. Accumulated new evidence shows that EWV in branches and upper stem parts develop earlier than EWV lower in the stem. The first EWV elements are fully expanded with differentiated secondary walls by the time of bud burst. In lower stem parts, perforations in vessel end walls are formed after bud burst and before the new leaves have achieved full size. Therefore, the current-year EWV network becomes functional for water transport only by the time when the first new leaves are mature.

2018 ◽  
Vol 9 (2) ◽  
pp. 60
Author(s):  
Kamlesh Kumar Sahu

Psychiatric Social Work teaching has completed seven decades in India which was started with master course in medical and psychiatric social work at Tata Institute of Social Sciences, Mumbai in 1948 followed by various schools of social work across the country but unfortunately even after two year full time or part time course they are not counted as a mental health professional; still they need two more years of specialized training in mental health as Master of Philosophy in Psychiatric Social Work (M.Phil. PSW) which was offered in just a few institutions. Recently the Government of India formulated manpower development schemes under the national mental health programme to address the shortage of men power in mental health. Under this scheme, 25 centre of excellence in mental health are already stabilised and various post graduate departments were upgraded and M.Phil. PSW course is started or will be started. This figure is in raise in Government intuitions and few private institutions also. The prominence of social work in mental health is expected to enhance by this effort as highly trained social workers will be available to practice in the mental health field but there are some challenges to overcome to get the maximum outcome from this opportunity to expand.    Keywords:Psychiatric social work, mental health, men power development, India  Â


Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Marcelo H. Jorge ◽  
Sara E. Sweeten ◽  
Michael C. True ◽  
Samuel R. Freeze ◽  
Michael J. Cherry ◽  
...  

Abstract Background Understanding the effects of disturbance events, land cover, and weather on wildlife activity is fundamental to wildlife management. Currently, in North America, bats are of high conservation concern due to white-nose syndrome and wind-energy development impact, but the role of fire as a potential additional stressor has received less focus. Although limited, the vast majority of research on bats and fire in the southeastern United States has been conducted during the growing season, thereby creating data gaps for bats in the region relative to overwintering conditions, particularly for non-hibernating species. The longleaf pine (Pinus palustris Mill.) ecosystem is an archetypal fire-mediated ecosystem that has been the focus of landscape-level restoration in the Southeast. Although historically fires predominately occurred during the growing season in these systems, dormant-season fire is more widely utilized for easier application and control as a means of habitat management in the region. To assess the impacts of fire and environmental factors on bat activity on Camp Blanding Joint Training Center (CB) in northern Florida, USA, we deployed 34 acoustic detectors across CB and recorded data from 26 February to 3 April 2019, and from 10 December 2019 to 14 January 2020. Results We identified eight bat species native to the region as present at CB. Bat activity was related to the proximity of mesic habitats as well as the presence of pine or deciduous forest types, depending on species morphology (i.e., body size, wing-loading, and echolocation call frequency). Activity for all bat species was influenced positively by either time since fire or mean fire return interval. Conclusion Overall, our results suggested that fire use provides a diverse landscape pattern at CB that maintains mesic, deciduous habitat within the larger pine forest matrix, thereby supporting the diverse bat community at CB during the dormant season and early spring.


Author(s):  
Karin Biering ◽  
Morten Frydenberg ◽  
Helle Pappot ◽  
Niels Henrik Hjollund

Abstract Purpose Fatigue following breast cancer is a well-known problem, with both high and persistent prevalence. Previous studies suffer from lack of repeated measurements, late recruitment and short periods of follow-up. The course of fatigue from diagnosis and treatment to the long-time outcome status is unknown as well as differences in the level of fatigue between treatment regimens. The purpose of this study was to describe the long-time course of fatigue from the time of clinical suspicion of breast cancer, its dependence of patient characteristics and treatment regimens and the comparison with the course of fatigue among women with the same suspicion, but not diagnosed with breast cancer. Methods Three hundred thirty-two women referred to acute or subacute mammography was followed with questionnaires from before the mammography and up to 1500 days. Fatigue was measured by the Multidimensional Fatigue Inventory (MFI-20). The women reported their initial level of fatigue before the mammography and thus without knowledge of whether they had cancer or not. Both women with and without cancer were followed. Women with cancer were identified in the clinical database established by Danish Breast Cancer Cooperative Group (DBCG) to collect information on treatment regimen. Results Compared to fatigue scores before diagnosis, women with breast cancer reported a large increase of fatigue, especially in the first 6 months, followed by a slow decrease over time. Despite the long follow-up period, the women with breast cancer did not return to their level of fatigue at time of the mammography. Women without breast cancer, experienced a rapid decrease of fatigue after disproval of diagnosis followed by a steadier period. Conclusions Fatigue is a persistent problem in women diagnosed with breast cancer, even several years following diagnosis and treatment. The women with breast cancer were most affected by fatigue in the first 6 months after diagnosis.


1995 ◽  
Vol 73 (6) ◽  
pp. 937-942 ◽  
Author(s):  
Heather Sinton Gerling ◽  
Arthur W. Bailey ◽  
Walter D. Willms

The response of Festuca hallii (Vassey) Piper to time of burning was examined on the Festuca–Stipa grasslands of the Aspen Parklands at the University of Alberta Ranch located 150 km southeast of Edmonton, Alberta. Two defoliation treatments (burning and mowing) were examined on five dates in 1978 (8 April, 27 April, 1 June, 31 July, and 18 October), corresponding to different phenological stages of F. hallii. Burning and mowing reduced the standing crop of F. hallii produced in the first growing season after treatment, but tiller densities increased. Defoliation in early spring (8 April) had little effect on the standing crop; apparently the increase in tiller density compensated for the reduction in tiller length. Inflorescence density also increased following burning or mowing from 8 April to 1 June. Soil temperature (3 cm deep) on previously burned or mown sites was greater than on the control the year after treatment. Festuca hallii tolerates single burns at any time of the year, but early spring fires have the greatest benefits by increased tillering and standing crop. Key words: standing crop, tiller number, leaf length, litter, defoliation, mowing.


2020 ◽  
pp. 135-147
Author(s):  
Yurii Shcatula ◽  
Volodymyr Votyk

Nowadays no herbicide has been approved for use on chickpea crops has been officially registered in Ukraine. Weed control measures are mainly used. However, many years of experience in the use of a number of herbicides in our country and in other countries. In this regard, the effectiveness and selectivity of soil preparations such as Harnes, 90% k.e., and Frontier Optima, 72% k.e. were studied in chickpea crops. These herbicides were applied after sowing chickpeas until the emergence of seedlings. Application of Harness herbicide, 90% k.e., at a rate of 3.0 l / ha in the soil before the emergence of chickpea seedlings leads to a decrease in weed vegetation a month after application of the herbicide to 88% compared to control areas where measures to protect against storms vegetation was not carried out. The regulation of the number of weeds and their harmful effects in chickpea agrophytocenoses to an economically harmless level is an important condition in the technology of its cultivation. The most relevant weed control is at the beginning of the growing season of the crop, since this the chickpea grows very slowly, is in the rosette phase for a long time, and therefore does not withstand competition from weeds. To increase the yield of chickpea seeds, an important place in the technology of growing crops is the use of herbicides and biological products. Inoculation of chickpea seeds with Rizobofitt at a consumption rate of 1 l / t and with a biofungicidal preparation Biopolycide at a consumption rate of 100 ml/t, by introducing a soil herbicide Frontier Optima, 72% k.e., at a consumption rate of 1,2 l/ha, contribute to the reduction of weeds to 91%, and the ability to obtain the yield of chickpea seeds at the level of 2,12 t/ha.


2011 ◽  
Vol 312-315 ◽  
pp. 387-392 ◽  
Author(s):  
Jaromír Drápala ◽  
Alena Struhařová ◽  
Daniel Petlák ◽  
Vlastimil Vodárek ◽  
Petr Kubíček

Problems of reactive diffusion at the solid phase and melt contact were studied theoretically and experimentally. The main intention was to calculate the time course of the solid phase dissolving in the case of cylindrical dissolving. These calculations were carried out on the assumption for the rate constant of dissolving K = const. In our work we give heed especially to the dominating process, which is the solid metal A dissolved in the melt B. During the dissolving the melt B saturates with the metal A and the process is influenced by convections which are characteristic for the given experimental configuration. A theoretical description of the kinetics of the solid phase dissolving in the melt will be presented for the case of cylindrical dissolving. The aim is to derive a relation for the interface boundary movement c(t) in dependence on time and a time course of growth of the element A concentration in the melt B. There are problems with accurate determination of the interface boundary movement after certain heating times of specimens, when it is observed experimentally, since intermetallic phases create in the original A metal at both the diffusion and cooling and some phases segregate at the solidifying melt cooling. The main intention was an experimental study of the copper dissolving in the tin melt. Experiments aimed to the determination of the Cu wires (diameters from 0.5 to 3.5 mm) dissolution in the solder melt were carried out at various selected temperatures and times. Rapid growth of phases in the metal A and determination of the thickness of layers with these phases pose considerable time demands to X-ray micro-analyses (WDX, EDX) of specimens after their long-time heating.


Toxins ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 371
Author(s):  
Juan Blanco ◽  
Aida Mauríz ◽  
Gonzalo Álvarez

The king scallop Pecten maximus retains the amnesic shellfish poisoning toxin, domoic acid (DA), for a long time. Most of the toxin is accumulated in the digestive gland, but this organ contains several cell types whose contribution to the accumulation of the toxin is unknown. Determining the time-course of the depuration by analyzing whole organs is difficult because the inter-individual variability is high. A sampling method, using biopsies of the digestive gland, has been developed. This method allows for repetitive sampling of the same scallop, but the representativeness of the samples obtained in this way needs to be validated. In this work, we found that the distribution of DA in the digestive gland of the scallops is mostly homogeneous. Only the area closest to the gonad, and especially its outer portion, had a lower concentration than the other ones, probably due to a transfer of the toxin to the intestinal loop. Samples obtained by biopsies can therefore be considered to be representative. Most of the toxin was accumulated in large cells (mostly digestive cells), which could be due to differences during the toxin absorption or to the preferential depuration of the toxin from the small cells (mostly secretory).


1986 ◽  
Vol 251 (2) ◽  
pp. F334-F347
Author(s):  
H. Sackin

The role of the paracellular interspace in solute-coupled water transport was investigated in isolated perfused salamander (Ambystoma) proximal tubules using a null-point technique to estimate interspace NaCl concentrations. Constant composition of luminal fluid was maintained by rapid (200 nl/min) perfusion of tubules 600,micron or less in length. Inhibition of active transport by a decrease in bath temperature from 22 to 0 degrees C in 400 ms produced rapid depolarizations of both the transepithelial (Vte) and basolateral (Vbl) potential, followed by slower changes in potential that occurred at low temperature. During this period, the time course of Vbl was independent of small changes in bath NaCl concentration, whereas the time course of Vte at low temperature varied from a slow depolarization to a slow repolarization depending on whether the concentration of NaCl in the bath equaled or exceeded that in the perfusate. Absence of a slow change in Vte at low temperature indicated a match between the NaCl concentration of the interspace and the test concentration of NaCl in the bath. Using this technique with 12 tubules, the normal interspace NaCl concentration appeared to be approximately 4% above the NaCl concentration of either the lumen or bath, demonstrating that the interspace of the salamander proximal tubule can function as a local hyperosmotic compartment to facilitate fluid transport between solutions of identical composition.


Author(s):  
Göran Gerdin ◽  
Per Göran Fahlström ◽  
Mats Glemne ◽  
Susanne Linnér

Finding and describing the optimal path to elite athletic performance has, for a long time, been a challenge for researchers. This study examined Swedish tennis coaches’ everyday practices for creating athlete development environments and the environmental factors that promote or hinder athlete development. The study was conducted in 2018–2019 and included in-depth focus groups with 13 Swedish full-time tennis coaches. Data were analyzed using thematic analysis and by drawing on models for studying athlete development environments. The results highlight how the coaches’ everyday work involves a range of administrative tasks, which ultimately means that there is little to no time left for focusing on athlete development. These results also draw attention to concerns about these professional coaches’ health, with increasing demands in their roles to manage administrative tasks in addition to the coaching and time spent on the court with their athletes. The results further reveal how the tennis clubs’ boards are increasingly interested in sound economy and high participation levels rather than focusing on performance outcomes and developing elite athletes. Finally, the results from this study emphasize the importance of increased collaboration and communication between clubs, coaches, regions, and the national association to create common and clearer guidelines for long-term athlete development. Future studies could engage in longitudinal and ethnographic work with tennis clubs of varying size and geographical locations, involving different stakeholders (e.g., coaches, management, parents, players) in order to further explore the environmental factors that promote or hinder athlete development.


Sign in / Sign up

Export Citation Format

Share Document