scholarly journals Germinación y establecimiento de plántulas de Pterocereus gaumeri, una cactácea columnar, rara y endémica de Yucatán, México

2017 ◽  
pp. 33
Author(s):  
Martha Méndez ◽  
Alfredo Dorantes ◽  
Gabriel Dzib ◽  
Jorge Argáez ◽  
Rafael Durán
Keyword(s):  
Open Space ◽  
Seedling Survival ◽  
Orientation Factor ◽  
Facilitative Effect ◽  
Critical Stage ◽  
Nurse Plants ◽  
Seedling Predation ◽  
Negative Effect ◽  
Four Levels ◽  
Very High

We examined the facilitative effect of nurse plants and the negative effect of predation on the germination and establishment of new individuals of Pterocereus gaumeri. The field experiment followed a factorial design, with five levels of association (four nurse plants and open space), four levels of orientation (North, South, East, and West) and two levels of predation (exclusion and non-exclusion of predators). There were no statistical differences between germination rates in open sites and under nurse plants, neither between nurse plants; however, seed germination was higher in the protected treatments. There were no statistical differences in the orientation factor for germination and survival. Seedling survival was higher under nurse plants than in open sites and seedling predation was very high. Our results showed that the recruitment of new individuals of P. gaumeri is a critical stage of the life cycle of the species and help explain the degree of rarity of this threatened cactus species.

Effects of nitrogen deposition on litter decomposition and nutrient release mediated by litter types and seasonal change in a temperate forest

2020 ◽  
Vol 100 (1) ◽  
pp. 11-25 ◽  
Author(s):  
Guoyong Yan ◽  
Xiongde Dong ◽  
Binbin Huang ◽  
Honglin Wang ◽  
Ziming Hong ◽  
...  
Keyword(s):  
Mass Loss ◽  
Litter Decomposition ◽  
Nutrient Release ◽  
N Deposition ◽  
Pinus Koraiensis ◽  
N Addition ◽  
Entire Study ◽  
Mixed Litter ◽  
Negative Effect ◽  
Four Levels

We conducted a field experiment with four levels of simulated nitrogen (N) deposition (0, 2.5, 5, and 7.5 g N m−2 yr−1, respectively) to investigate the response of litter decomposition of Pinus koraiensis (PK), Tilia amurensis (TA), and their mixture to N deposition during winter and growing seasons. Results showed that N addition significantly increased the mass loss of PK litter and significantly decreased the mass loss of TA litter throughout the 2 yr decomposition processes, which indicated that the different responses in the decomposition of different litters to N addition can be species specific, potentially attributed to different litter chemistry. The faster decomposition of PK litter with N addition occurred mainly in the winter, whereas the slower decomposition of TA litter with N addition occurred during the growing season. Moreover, N addition had a positive effect on the release of phosphorus, magnesium, and manganese for PK litter and had a negative effect on the release of carbon, iron, and lignin for TA litter. Decomposition and nutrient release from mixed litter with N addition showed a non-additive effect. The mass loss from litter in the first winter and over the entire study correlated positively with the initial concentration of cellulose, lignin, and certain nutrients in the litter, demonstrating the potential influence of different tissue chemistries.

scholarly journals Immediate rehabilitation with feeding appliance of a three day old neonate with cleft lip and palate- a case report

2017 ◽  
Vol 13 (2) ◽  
pp. 293-295
Author(s):  
Deepika Kapoor ◽  
Deepanshu Garg
Keyword(s):  
Case Report ◽  
Cleft Lip ◽  
Multidisciplinary Approach ◽  
Cleft Lip And Palate ◽  
Facial Growth ◽  
Orofacial Clefts ◽  
High Incidence ◽  
Negative Effect ◽  
Growth Development ◽  
Very High

Orofacial clefts (OFC) are one of the most common congenital problems seen with a very high incidence. It imparts a negative effect on the overall health of the child by hindering in his feeding practices, normal facial growth, development of dentition and hence speech. Infants born with orofacial clefts have oronasal communication which creates a problem with the creation of negative pressure inside the oral cavity required for suckling.The treatment for such patients is with the multidisciplinary approach but the preliminary  concern for the neonate is to help with the feeding for which a feeding appliance is given. This case report presents a case of a 3-day old infant to whom a feeding appliance was given to aid in suckling. 

Direct seeding of PinusSylvestris using microsite preparation and invigorated seed lots of different quality: 2-year results

1994 ◽  
Vol 24 (1) ◽  
pp. 77-86 ◽  
Author(s):  
Hans Winsa ◽  
Urban Bergsten
Keyword(s):  
Seed Quality ◽  
Seedling Survival ◽  
Seedling Emergence ◽  
Mineral Soil ◽  
Direct Seeding ◽  
Growing Seasons ◽  
Humus Layer ◽  
Negative Effect ◽  
Mean Germination Time ◽  
Better Than

Direct seeding of Pinussylvestris L. is a regeneration method, with potential for development considering scarification, microsite preparation, seed invigoration, and seed quality. Three seed lots of different quality concerning seed weight, germination percent, and mean germination time were used on two sites in northern Sweden. Microsite preparation, 2 cm deep pyramidal indentations, of the mineral soil improved seedling emergence on the two sites by 48 and 62%, respectively, compared with seeding without preparation other than removal of the humus layer. Microsite preparation in combination with invigorated seed, i.e., seed incubated at 30% moisture content for 7 days at 15 °C, resulted in seedling emergence of about 85% for the highest and about 50% for the lowest seed quality at both sites. Noninvigorated seed, seeded without microsite preparation, reached about 55% for the highest and 22% at one and 43% at the other for the lowest seed quality. Without microsite preparation there was no, or a negative, effect of seed invigoration on seedling emergence. Seedling survival after the first winter improved significantly with better seed quality. Survival averaged 92 and 72% at the two sites, with frost heaving causing most mortality. Seedlings from invigorated and redried seed survived better than seedlings from untreated seed. Seedlings from the best seed quality had higher values in seedling height, about 35%, shoot length, about 60%, and needle length, about 30%, after two growing seasons than seedlings from lower seed qualities. Invigoration and microsite preparation had no effect on measured growth characteristics.

Coordinated trials on the protein requirements of sows 1. A comparison of four levels of dietary protein in gestation and two in lactation

1977 ◽  
Vol 24 (3) ◽  
pp. 307-321 ◽  
Author(s):  
J. F. D. Greenhalgh ◽  
F. W. H. Elsley ◽  
D. A. Grubb ◽  
A. L. Lightfoot ◽  
D. W. Saul ◽  
...  
Keyword(s):  
Protein Intake ◽  
Treatment Combination ◽  
Protein Requirements ◽  
Satisfactory Performance ◽  
Additional Group ◽  
Negative Effect ◽  
Four Levels ◽  
Time Required ◽  
Positive Effect ◽  
Size At Birth

SUMMARY1. Gestation diets formulated to contain A, 9; B, 11; C, 13 or D, 15% protein, and lactation diets with C, 13 or E, 17% protein provided eight treatment combinations. They were given at seven centres at 2 kg/day in gestation and approximately 5·7 kg/day in lactation to sows which remained on experiment for three to five parities and produced in total 468 litters. Mean results for parities one to four are given in this summary.2. For gestation diets A to D mean litter size at birth was 9·7, 10·1, 10·3 and 10·4 live pigs, and at weaning (at 6 weeks), 8·2, 8·7, 8·8 and 8·8. Sows which received lactation diets C and E subsequently produced 10·4 and 10·3 pigs at birth and 8·9 and 8·3 at weaning.3. Gestation diets had no consistent effects on piglet weights. During lactation, however, diet E gave heavier pigs than C, by 0·2 kg at 3 weeks and 0·5 kg at weaning.4. Extra protein for either gestation or lactation had a positive effect on sow weight at that stage, but a negative effect in the following stage. There were no direct treatment effects on the time required for re-conception.5. Twenty experimental sows at the Rowett Institute, together with an additional group given diet A for both gestation and lactation, showed strong positive relationships between lactation protein intake and milk yield or composition.6. The treatment combination AC (i.e. 9% protein in gestation and 13% in lactation) gave the lowest weight of weaned pigs per litter, and CC gave the highest. The remaining treatments gave similar weights; of these BC (nominally 11 with 13, but actually 11·5 with 13·5% protein) was concluded to provide the lowest protein intake consistent with satisfactory performance.

scholarly journals WADAH AKTIVITAS DAN KOMUNITAS PESISIR DI MUARA BARU

2020 ◽  
Vol 2 (1) ◽  
pp. 155
Author(s):  
Febi Claudia Lie ◽  
Lina Purnama
Keyword(s):  
Public Space ◽  
Open Space ◽  
Knowledge Exchange ◽  
Positive Interactions ◽  
The Road ◽  
Surrounding Environment ◽  
Housing Area ◽  
Local Residents ◽  
The City ◽  
Very High

Jakarta was developed started from the coastline and gradually moved to the centre of the city which left the coastal area remain untouch. The development of Jakarta which only oriented on capitalism cause in a lack of public space for the community, which make public coping with the issues independently. The roads in the housing area and villages was used by local residents as a space to socialize with neighbors or a place to do activities. There are still lots of kampung remained in Muara Baru which located in North Jakarta, but not facilitated by public space and open space to accommodate the citizen’s need to socialize and do their activity, so they carried out those activities in the middle of the road or alley which can disturb the traffic and endangered other people’s lives.  This phenomenon indicates that the community's need for public space is very high and needs to be anticipated immediately in order to avoid environmental and social degradation. The purpose of this project is to become a linkage that connect people with the surrounding environment, as well as humans with other humans, while this project also help the economy and home industry businesses, which bring in money to help the economy of local citizens, and cause positive interactions, such as knowledge exchange and development in economic aspects. AbstrakPembangunan kota Jakarta awalnya dimulai dari area pinggir laut yang kemudian semakin berkembang ke pusat kota, seiring berlangsungnya pembangunan di pusat kota, daerah pinggir/pesisir mulai ditinggalkan dan tidak tersentuh. Pengembangan kota Jakarta yang hanya berorientasi pada kepentingan kapitalis juga mengakibatkan kurangnya ruang publik bagi masyarakat, sehingga  mengakibatkan masyarakat mengatasinya secara mandiri. Jalan-jalan di dalam perumahan hingga perkampungan yang difungsikan oleh warga setempat sebagai ruang untuk bersosialisasi dengan tetangga atau tempat melakukan aktivitas. Kawasan Muara Baru yang terletak di wilayah pesisir Jakarta bagian Utara, masih terdapat banyak area perkampungan, tetapi tidak difasilitasi oleh ruang publik atau ruang terbuka sehingga untuk melakukan kegiatan berinteraksi dan beraktivitas, dilakukan di jalan/lorong kecil didepan rumah, yang dapat mengganggu lalu lintas dan juga membahayakan keselamatan warga dan juga pengguna jalan. Fenomena ini menandakan bahwa kebutuhan masyarakat akan ruang publik sangat tinggi dan perlu segera diantisipasi agar tidak terjadi degradasi lingkungan dan sosial, sehingga tujuan dari proyek ini adalah sebagai linkage yang menggabungkan manusia dengan lingkungan di sekitarnya, serta manusia dengan manusia lainnya, selain itu juga untuk membantu perekonomian dan usaha industri rumahan, yang dapat dilakukan serta menghasilkan uang untuk membantu perekonomian warga, serta menimbulkan interaksi positif, seperti pertukaran ilmu dan pembangunan aspek ekonomi, yang ke depannya akan menghasilkan kemajuan pada kota Jakarta dengan aspek sosial dan ekonomi yang seimbang.

Driving Performance under Nighttime Conditions of Visual Degradation

1967 ◽  
Vol 9 (5) ◽  
pp. 427-432 ◽  
Author(s):  
Francisco Matanzo ◽  
Thomas H. Rockwell
Keyword(s):  
Driving Performance ◽  
Task Group ◽  
Vehicle Speed ◽  
Dependent Variables ◽  
Visual Degradation ◽  
Four Levels ◽  
Instrumented Vehicle ◽  
Lane Position ◽  
Nighttime Driving ◽  
Very High

Nighttime driving performance was studied in relation to four different driving tasks and four levels of visual degradation. Four matched but task-differentiated groups of four Ss each drove an instrumented vehicle at night on a superhighway. The four levels of visual degradation presented the roadway to the driver at overall luminance levels of 5.228 mL, 2.688 mL, 0.755 mL, and 0.168 mL. The two dependent variables were vehicle speed and vehicle distance from the white shoulder line. The visual degradation caused the Ss to slow down and position the vehicle slightly farther away from the shoulder. It was found that a driver also is capable of driving at a constant speed and of maintaining a constant lane position at very high degrees of visual degradation. These results were explained by the different instructions given to each task group.

Experimental Validation of an Intelligent Hybrid Plain Bearing Active Control

2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Clément Eberhardt ◽  
Robin Kurth ◽  
Christian Kraft ◽  
Hubert Schwarze ◽  
Thomas Päßler ◽  
...  
Keyword(s):  
Load Capacity ◽  
Hydrodynamic Pressure ◽  
Strong Increase ◽  
Plain Bearing ◽  
Press Hardening ◽  
Negative Effect ◽  
Clamping System ◽  
Smart Machine ◽  
Very High

Abstract The replacement of damaged journal bearings in forming machines eventuates in very high personal and material costs as well as long-term downtime. Moreover, new discontinuous forming processes (e.g., press hardening and pendulum operations) have a negative effect on the hydrodynamic pressure built up in the bearing and can lead to failure. Therefore, users and manufacturers of forming presses are looking for ways to improve the safety of this key component. In this paper, the concept of an intelligent hybrid plain bearing (IHPB) that combines hydrodynamic and hydrostatic characteristics, presented by Kurth et al., (2019, “Forming 4.0: Smart Machine Components Applied as a Hybrid Plain Bearing and a Tool Clamping System,” Proc. Manuf., 27, pp. 65–71), is detailed and validated on a test rig. The clearance state of the journal bearing is monitored through eddy current sensors and a controlled hydrostatic support is activated, when this state is evaluated as critical. The results show a strong increase in the load capacity and in the minimal lubrication gap of the IHPB within three series of tested experiments: stationary, nonstationary, and press-typical load cases.

scholarly journals Investigation of the Factors Affecting Artificial Seed Sowing Success and Seedling Survival in Pinus brutia Natural Stands in Middle Elevations of Central Cyprus

Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1349
Author(s):  
Petros Petrou ◽  
Elias Milios
Keyword(s):  
Seedling Survival ◽  
Mortality Rates ◽  
Point Of View ◽  
Factors Affecting ◽  
Pinus Brutia ◽  
Artificial Seed ◽  
Hemispherical Photographs ◽  
Seed Sowing ◽  
Natural Stands ◽  
Very High

The aim of this study was to analyze the germination of Pinus brutia Ten. seeds, in the field, in relation to factors such as period of sowing, light environment, and watering, in sites of different productivity in the middle elevations in central Cyprus. Two sowing experiments were conducted in three sites of different productivity. In the first experiment P. brutia seed sowing took place in February 2009 in two sowing environments which were gap and under canopy environments. The shade conditions in those environments were determined using hemispherical photographs. Also, the influence of watering on the seed germination was checked. In the second experiment, which was established in the same areas as in the first experiment, the seed sowing took place in December 2009. However, in this case, no watering was applied during the germination period. Moreover, the survival of the seedlings from both sowing periods were monitored up to the end of 2010. During the period of monitoring, the influence of watering was checked. The germination rates of seeds from the February sowing were very low. On the contrary, from the December sowing, the germination rates of seeds were very high in both sowing environments in all studied sites. In the case of seedling survival from the February and December sowing, mortality rates were relatively high in all sites except from the under-canopy sowing environment where watering was applied in the medium productivity site. From the December sowing, from a practical point of view, the number of survived seedlings, in all the plots of the three sites can be considered adequate for the successful regeneration of P. brutia.

Habitat use, but not dispersal limitation, as the mechanism behind the aggregated population structure of the mygalomorph species Atypus affinis

2012 ◽  
Vol 62 (2) ◽  
pp. 181-192 ◽  
Author(s):  
Julien Pétillon ◽  
David Deruytter ◽  
Arthur Decae ◽  
David Renault ◽  
Dries Bonte
Keyword(s):  
Habitat Use ◽  
Calluna Vulgaris ◽  
Dispersal Limitation ◽  
High Dispersal ◽  
Negative Effect ◽  
Dispersal Abilities ◽  
Dispersal Propensity ◽  
Positive Effect ◽  
Very High ◽  
Habitat Variables

Dispersal and habitat selection are the main factors that affect the distribution of species in spatially structured habitat. Species typically occurring in an aggregated way are supposed to experience dispersal limitation or to be highly selective for specific habitat attributes in their environment. In order to understand the distribution pattern of a mygalomorph spider species, Atypus affinis, we conducted an intensive survey to detect correlations of spider densities with specific habitat variables and empirically tested the dispersal propensity of spiderlings. In the field, the spiders exhibited an aggregated distribution correlated with patches of heathlands (dominated by Calluna vulgaris). Contrary to our expectations, laboratory experiments revealed a very high dispersal propensity in juveniles (more than 80% of individuals dispersed at least once during two experiments). This dispersal was strongly context dependent with a pronounced negative effect of starvation and a positive effect of clutch size. Kin competition is hypothezised to be the driving force behind these high dispersal abilities. The aggregation of A. affinis is a likely result of habitat use rather than dispersal limitation.

scholarly journals Planting depth - effective agricultural practice perventing lodging of seedstalks of onion seeds

2020 ◽  
Vol 224 ◽  
pp. 04011
Author(s):  
V. E. Lazko ◽  
O V Yakimova
Keyword(s):  
Seed Yield ◽  
Biochemical Composition ◽  
Soil Layer ◽  
Breeding Site ◽  
Soil Horizon ◽  
Agricultural Practice ◽  
Seed Productivity ◽  
Planting Depth ◽  
Negative Effect ◽  
Very High

At the breeding site of the winter onion variety Ellan, the effect of the planting depth of mother bulbs of two fractions on lodging of stems and seed productivity was studied. It was found that in winter, with the depth of planting the bulbs in the soil horizon, the processes of differentiation and the formation of microstalks noticeably slow down, and the biochemical composition of the bulbs shows a decrease in the activity of metabolic processes. Thanks to this and the buffering properties of the soil, the safety of plants in winter is very high when planted to a depth of 15 cm. Deeper planting has a negative effect on the growth of leaves. At a planting depth of 15-20 cm, the stems remain upright due to the soil layer. The angle of inclination of 82 ... 86% of the stems is not more than 450 and occupies no more than 50 cm of the width of the projection of the row. When planted to a depth of 10 cm, the stems crumble, agronomic measures, the phytosanitary state of seed production and harvesting are hampered. It was found that the effect of bulb size on seed productivity of one stem is 42%. The increase in planting for the yield of one plant and the yield is 44 ... 45%. When setting seed onions, it is recommended to plant uterine bulbs to a depth of 15 cm. This planting depth ensures the maximum safety of the bulbs in winter, excludes lodging of the stems and the maximum possible seed yield. There is no need for additional hilling or tying of the stems, as with a planting depth of 10 cm.

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