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The study's main objective is to investigate the effects of COVID-19 on the highereducationinstitutionsinMogadishu,Somalia.Thedurationoftheresearchwasfifteendays,involvingtwohundredrespondents. The result shows that 56% of the educational foundations were closed during the initialstages of the pandemic, as per the government guidelines. According to the data,22.5% of higher education institutions were partially closed and reported significantdisruptions.Ontheotherhand,13%ofhighereducationestablishmentswereopenforbusinessandtooknomeasurestodealwithCOVID-19.Mostrespondentsinthestudy,126 (66.7%), utilized Zoom Meeting to conduct classes and other activities, while 40(21.2%)usedGoogleStudyHall. The primary constraint of online classes is that there are fewer personal meetingsbetween the lecturers and students. In addition, online learning does not permitstudents to seek more clarification during the lessons. The challenge is to make theinternetavailabletoallstudents. Keywords: Impact, COVID-19, Higher Education, Private Universities, Somalia, and E-learning.

Scots pine sapwood was pretreated with two levels of propanetriol (20% and 40% w/w glycerol), and then subjected to vacuum-heat treatment (VHT) at 180 degrees C and 200 degrees C. The treated samples were examined with respect to their weight and volumetric changes, mechanical properties, colour changes, and dynamic water vapour sorption. The weight of the samples after VHT did not change with increasing the temperature, but it was increased in glycerol pretreated samples. Combination of glycerol pretreatment and VHT decreased the maximum swelling. Total colour change was significantly higher during VHT at a higher temperature, while no obvious trend observed in the samples pretreated with glycerol. Modulus of elasticity (MOE) and modulus of rupture (MOR) were not affected by solely VHT, but strongly decreased after glycerol pretreatment. The equilibrium moisture content (EMC) of the samples decreased by VHT. The glycerol pretreatment caused a reduction in EMC values at a relative humidity (RH) below 60%, but considerably increased the moisture sorption in the RH above 75%. VHT slightly reduced the sorption hysteresis compared to untreated wood, but an apparent reduction in hysteresis observed by glycerol pretreatment. This indicates that the flexibility of the wood cell wall polymers increases due to glycerol pretreatment, which results in decreased MOE and sorption hysteresis values.

Background of this paper hence distinguishes the high-influence practice principles of online progressed instruction and gives a logical examination to partners at schools to think driving on the internet preparing in relative conditions. Appraisal is probably going the foremost moving idea to be adjusted to the present new instructive framework, and various colleges are worried about the way to affect a right assessment of understudies, aptitudes and knowledge. The principle target of this investigation is to look at the effect of COVID-19 on instruction Mogadishu-Somalia. The methodology of this examination was utilized elucidating inspecting and was directed on advanced education that lives in Mogadishu Somalia. We’ve done a study for 15 days, thanks to time requirements: we began to in more than 200 respondents. The results of this examination are that the most scholastic foundations were shut 28 (56%) yet some scholarly establishments 45 (22.5%) had said “our organization is incompletely open, yet there are significant interruptions”, while 27 (13.5%) were said “our foundation is open in fact, no unique measures found out for COVID-19.” The foremost respondents 126 (66.7%) were utilized zoom meeting, 40 (21.2%), they utilized Google study hall. The foremost guardians said yes as typical 79 (73%) when asked guardians, “Dear guardians; Are you completing routine exercises with regard to COVID-19.” Many difficulties of COVID-19 are less conversation of teachers and understudies about the course. The cycle of the Internet learning doesn’t permit understudies to urge more clarification. The treats of this condition are monetary issues since you’ve got to urge web information to urge to your organization to get access E-learning and Meeting meetings, then forth. Conclusion For the understudies, the foremost quick effect has normally been that the impermanent end of up close and private instructing at an advanced education foundation has left them, especially students and therefore, the individuals who are getting to complete upper optional and check out to enter advanced education, during a totally new circumstance, without a far away from of how long it’ll keep going, prompt effects on a day life, costs caused and money related weights and, obviously, learning coherence and global portability.

Rattan cane is an important forest product with economic value. Its anatomical, physical, and biological properties vary with the cane height. This makes it difficult to select the appropriate cane diameter for harvesting. Understanding the material properties of rattan cane with different diameter sizes is important to enhance its utilization and performance for different end uses. Thus, the present study was performed on two rattan species, Calamus zollingeri and Calamus ornatus, at two different cane heights (bottom/mature and top/juvenile). Calamus zollingeri was studied at diameter classes of 20 mm and 30 mm, while Calamus ornatus was analyzed at a diameter class of 15 mm. The anatomical properties, basic density, volumetric swelling, dynamic moisture sorption, and biological durability of rattan samples were studied. The results showed that C. zollingeri with a 20 mm diameter exhibited the highest basic density, hydrophobicity, dimensional stability, and durability against mold and white-rot (Trametes versicolor) fungi. As confirmed by anatomical studies, this could be due to the higher vascular bundle frequency and longer thick-walled fibers that led to a denser structure than in the other categories. In addition, the lignin content might have a positive effect on the mass loss of different rattan canes caused by white-rot decay.

Background: The yolk sac is the first anatomical structure identified ultrasonographically within the gestational sac and acts as the primary route of exchange between the human embryo and the mother before the placental circulation is established.Aim of Study: To determine whether yolk sacs with an abnormal sonographic appearance in pregnancies at 5-10 weeks gestation, are associated with adverse pregnancy out-comes or not.Patients and Methods: This study included one hundred pregnant women who are between 5-10 weeks of gestation at Tanta University Hospitals. They were prospectively evaluated concerning for sonographic characteristics of the yolk sacs and perinatal outcomes.Results: An abnormal yolk sac was found in 42 pregnan-cies. In pregnancies with enlarged yolk sacs, a miscarriage occurred in 71.4% of cases (5/7). The pregnancies with a yolk sac diameter ³6mm had a significantly higher risk of miscar-riage (p=0.001). Miscarriage occurred in 29.4% of pregnancies with irregular yolk sacs (5/17) and 30.8% of pregnancies with echogenic yolk sacs (4/13).Conclusions: An enlarged yolk sac is strongly associated with a significantly increased risk for miscarriage. The presence of an echogenic or irregular yolk sac appears to be unrelated to adverse perinatal outcome.

The study's main objective is to investigate the effect of COVID-19 on the higher education institutions in Mogadishu-Somalia. The duration of the research was fifteen days, engaging two hundred respondents. The result shows that most educational foundations, namely 56%, were closed during the initial stages of the pandemic as per the government guidelines. According to the data, 22.5% of higher education institutions were partially closed and reported significant disruptions. On the other hand, 13% of higher education establishments were open for business and took no measures to deal with COVID-19. Most respondents in the study, 126 (66.7%), utilized Zoom meetings to conduct classes and other activities, while 40 (21.2%) used Google study hall. The main constraints that internet classes faced include fewer personal meetings between the lecturers and students. Also, internet learning does not permit students to seek more clarification during the lessons. The challenge is to make the internet available to all students.

Water is one of the most significant factors for the durability of wood. A common solution is to use a coating to protect and maintain low water content. However, little knowledge exists how the underlying wood substrate affects the water sorption of coated wood. Therefore, the liquid water absorption of coated and uncoated Norway spruce heartwood and sapwood with a variety of densities was measured by letting the panels float freely in the water. The effect of one year weathering of the coatings was also included. Coated heartwood and sapwood had no difference in water absorption in opposite to uncoated spruce. The influence of heartwood and sapwood seemed to have limited impact when a coating hindered the presence of free water. Wood density had a positive effect on the absorption of coated wood, i.e. low absorption for low-density samples, in opposite to uncoated samples. Low-density characteristic also contributed to a lower increase of water absorption after weather degradation, for samples with water-borne coatings. Natural weathering enhanced the effect of wood characteristics on coated samples, likely by an increase of coating permeability.

In musical instrument making, there is a strong need to find alternatives to the traditional endangered and expensive tropical wood species used today. The present study examined whether different commercial and experimental modified wood materials have the necessary acoustic qualities under different humid conditions (dry, standard and wet) to contribute to the use of raw materials for wooden musical instruments. The materials were thermally-modified wood (ash, aspen and birch), acetylated wood (beech, maple and radiata pine), melamine- and phenol formaldehyde-treated beech and furfurylated Scots pine (Kebony Scots pine). Investigations involved physical (density ρ, Equilibrium moisture content EMC, volumetric shrinkage) and dynamic elastic testing by a free-free flexural vibration method to determine various acoustic characteristics: specific dynamic modulus (MOEdyn/ρ), damping coefficient (tanδ), speed of sound (c), specific acoustic impedance (z), sound radiation coefficient (R) and acoustic conversion efficiency (ACE). The modified materials and especially acetylated wood showed low EMC values and high dimensional stability at each humidity level, which are considered important factors for making quality musical instruments. Based on the obtained value ranges of all acoustical properties, the different modified wood materials could find uses in musical instruments where specific characteristics of sound are required. Furthermore, most of the modified materials showed an excellent acoustic performance in the three humid conditions based on a high ACE and low tanδ. Furfurylated Scots pine and phenol formaldehyde-treated beech showed an inferior acoustic quality with the lowest ACE and the highest tanδ, which is a less favourable combination for most of the musical instruments.

The block shear strength of Norway spruce (Picea abies (L.) Karst.) glulam joints was tested under low temperatures. Glulam samples were glued with the three of the most common outdoor structural adhesives. The cold temperatures tested were 20, −20, −30, −40, −50, and −60 °C. Within the temperature test range, the block shear strength of the glulam joints was resistant to the effect of temperature. As the temperature decreased, the joints’ block shear strength did not show any significant change. In most cases, phenol-resorcinol-formaldehyde (PRF) adhesive yielded the strongest block shear strength, while melamine-formaldehyde (MF) adhesive yielded the weakest block shear strength. Melamine-urea-formaldehyde (MUF) adhesive yielded similar results to those of MF adhesives for all temperatures tested. The block shear strengths of the glulam joints with PRF, MUF, and MF adhesives were not sensitive to temperature change. The results indicated that PRF, MUF, and MF adhesives are stable for outdoor structural engineered wood construction in cold climates. The results also suggest that the SS-EN 14080 (2013) standard for the block shear method may not be the proper standard for testing differences in shear strength at different temperatures. The EN 302-1 (2011) standard could be more suitable for this purpose.

The development of mould on wood surfaces depends on several factors. Although mould does not affect the mechanical properties of wood, it greatly reduces the aesthetic value of wood such as the sapwood of Scots pine (Pinus sylvestris L.), which is very prone to mould. In addition, adverse health effects of mould on humans are a great concern. Different types of dried and treated wood were used to observe whether they had enhanced durability against mould following an accelerated laboratory test method in a climate chamber. Samples were green, air-dried, industrially thermally modified, treated with copper-based preservative, and kiln-dried wood, which were tested within a single test run. The test produced the following main results: The thermal modification increased the durability of the wood, and the protective effectiveness of alternative treatments was comparable to that of commercially available copper-based treatment. However, the initial moisture content of the samples during mould exposure had a great influence on the onset of mould growth. The risk of mould susceptibility of industrial kiln-dried lumber can be reduced by drying using the double-layering technique and planing off the nutrient enriched evaporation surfaces.

Approximately, 13.5 % of the standing volume of productive forest land in Sweden is covered by birch and aspen, which provides the vast potential to produce value-added products such as densified w ...

We test the hypothesis that the combination of kiln drying of double-stacked boards and contact heat treatment will reduce the susceptibility of treated boards to colonization by mold fungi. Winter ...

The purpose of this study was to develop fast, simple and robust solid wood mould testing methods for the use in small-scale laboratory tests. The objective was to investigate mould susceptibility of different wood materials within the batches. The proposed method is based on natural contamination of non-sterile surfaces in climates conducive to mould growth. For this purpose, a climate chamber with regulated temperature and relative humidity was used. The conditioning chamber was divided into upper and lower chamber by a thin layer of stainless steel placed horizontally above the fan to minimise air circulation to the sample in the upper compartment. Mould-infected samples from outdoor tests were used as a source of mould inocula, and test trials were conducted on Scots pine (Pinus sylvestris L.) sapwood. Samples were suspended from the top of the upper chamber, and the chamber was exposed to different temperature and humidity levels. Severe mould infestation was observed after 12–14 days of incubation. Visual mould rating was then performed. Regardless of some constraints, this test method was very simple, fast, and effective. More importantly, unlike other test methods, it closely models mould infestation as it would occur under natural condition.

The aim of this experiment was to impregnate thermally modified wood using an easy and cost-effective method. Industrially processed thermally modified European aspen (Populus tremula L.) and birch (Betula pubescens Ehrh.) were collected and secondarily treated at the laboratory scale with the preservatives tung oil, pine tar and Elit Traskydd (Beckers) using a simple and effective method. Preservative uptake and distribution in sample boards were evaluated using computed tomography (CT) and scanning electron microscopy (SEM) techniques. Preservative uptake and treatability in terms of void volume filled were found the highest in Beckers and the lowest in tung oil-treated samples. Thermally modified samples had lower treatability than their counterpart control samples. More structural changes after thermal modification, especially in birch, significantly reduced the preservative uptake and distribution. The differences of preservatives uptake near the end grain were high and then decreased near the mid position of the samples length as compared with similar type of wood sample. Non-destructive evaluation by CT scanning provided a very useful method to locate the preservative gradients throughout the sample length. SEM analysis enabled the visualization of the preservative deposits in wood cells at the microstructural level.

Different types of fertilizers are widely used throughout the world for successful crop production. Chemical fertilizers have some adverse effects on the environment if used indiscriminately and are a major source of soil and water pollution. To minimize environmental pollution, use of slow-release fertilizer (SRF) in agricultural practices is an important and effective method. Different materials have been used so far to formulate SRF, but SRF from wood is a unique technique which reflects a new dimension of wood use. In this aspect, present study was designed to develop a slow-release nitrogen fertilizer using three kinds of woodchips: Japanese red pine (Pinus densiflora S. et Z.), eunsasi poplar (Populus tomentiglandulosa T. Lee), and konara oak (Quercus serrata Thunb.). Fertilizers were prepared from woodchips after full-cell treated with a saturated solution (2140 g/l at 25°C) of ammonium nitrate (NH4NO3). The morphology of woodchip fertilizer was investigated by using a field-emission electron microscope (FE-SEM) equipped with an energy-dispersive X-ray (EDX) spectrometer to locate NH4NO3 in woodchips. Deposition of nitrogen in the cell lumen was verified by FE-SEM. Deposition inside the cell wall was confirmed by EDX mapping. This study also evaluated the release pattern of nitrogen from impregnated woodchips in distilled water for 768 h and found that nitrogen was released from poplar, pine, and oak in a slow-release pattern. The encapsulated nutrient in the void volume of wood facilitated the slow release. The above findings confirm that woodchip fertilizers can be used as a slow-release nitrogen source for plants.

Scots pine (Pinus sylvestris L.) sapwood lumber was collected after kiln drying and preservative treatment with Celcure AC 800 (a copper-amine wood preservative). Distribution of the preservative throughout the lumber was visually examined. Not all, but some samples showed specific localized areas without any preservative distribution throughout their entire length. Those samples were assessed further for anatomical properties, specifically in impregnated and unimpregnated areas. Additional study was conducted on the morphological nature and redistribution of lipophilic extractives using three different histochemical staining methods. Intrinsic wood properties – especially the frequency of axial resin canals and the percentage of canals blocked – were found to be responsible for the irregular distribution of the preservative. Furthermore, the inability to create continuous and frequent interstitial spaces due to the collapse of thin-walled ray cells throughout the lumber resulted in un-even distribution of preservatives. Staining techniques were useful to localize places with more or less abundance of extractives (e.g., fats) in impregnated and unimpregnated wood, which varied considerably. Histochemical observations revealed information pertaining to the kiln dry specific distribution and redistribution of extractives between the areas. Moreover, resin reallocation and modification in ray parenchyma and resin canals induced by kiln drying would be another reason for the impregnation anomalies.

Two experimental techniques were used to test the water permeability of two Korean hardwood species: diffuse porous Populus tomentiglandulosa T. Lee (eunsasi poplar) and ring porous white oak, Quercus serrata Thunb (konara oak). The first technique measured the void volume filled at different moisture content (MC) levels. Samples were treated with water via a schedule of full-cell impregnation. A significant relation between MC and permeability (the fractional void volume) was found. A reduction in liquid permeability was observed at MC above the fiber saturation point (FSP), whereas the opposite result was observed at MC below FSP due to the effect of the voids available in the wood. However, the differences of increased permeability from MC level 20% to 0% were found satistically the same in either wood species. The second technique measured the speed of liquid penetration in vessels, fibers, and rays with no application of external pressure. In this method, liquid flow was captured via video and the penetration speed was measured. Vessels, fibers, and rays in poplar were found to be more permeable than those in oak. Different anatomical factors such as cell diameter, cell length, pit number, pit aperture area, and thickness of the pit membrane seemed to be responsible for the variation of liquid flow rate in different cells of the two hardwood species.

This experiment describes some anatomical features of Tectona grandis L. relating to the variation of liquid permeability in radial and longitudinal directions. Safranine aqueous solution was used to measure the permeability for its brilliant color and staining properties. Even in presence of abundant rays, penetration depth of liquid in radial direction was found very low in comparison with axial flow. Herein ray length and perimeter of cross-sectional area, interparenchymatous pit number and diameter determined the radial permeability. On the other hand, vessel length and diameter, intervessel pit size, and fiber length affected the longitudinal flow of liquids. Following a go-stop-go cycle, penetration speed of liquid decreased over time.

This paper explains the effects of wood drying on treatability (as determined by water uptake) of Japanese red pine (Pinus densiflora S. et Z.) at the sevenmoisture content (MC) levels above and below the fiber saturation point (FSP). According to the experimental results, it was found that water uptake (as the percentage of void volume filledwith distilled water, VVF%) was influenced by level of moisture con-tent and percentage of void volume filled was improved effectively by kiln drying process. A significant relationship between moisture content and treatability was established. Permeability and liquid uptake weredecreased above the FSP due to the effect of the less void space available in wood. Even though increased liquid uptake was observed at lower moisture content, no significant differences was observed moisture content below 20%. Therefore, this species need to be initially dried below FSP before treated with liquids. But drying moisture content below 10% might not be economical for the commercial purpose comparing drying the wood between 10 and 20% moisture content. The result of this study inferred that the treat-ability of pine wood can be improved by reducing the moisture content up to a certain level of 10∼20% for allowing better performance. Keywords : Japanese red pine, moisture content, wood drying, treatability, anatomical characteristics

Wood from three tree species was used for making slow-releasing woodchip fertilizer. Fertilizer made from Populus tomentiglandulosa retained the highest amounts of N (29.04%), P2O5 (26.03%) and K2O (16.93%). On the other hand, woodchip fertilizer made from Pinus koraiensis retained the lowest amounts of N (26.22%), P2O5 (21.80%) and K2O (14.49%). A field experiment was performed in a 50 m2 experimental plot at Gangwon Agricultural Research and Extension Services, Chuncheon, Korea from August to November 1999. The effects of a general fertilizer along with compost and slow releasing woodchip fertilizer without compost on the cabbage production were observed. Cabbage production parameters, such as top height, head weight, head height, head width, number of outer and inner leaves, leaf width and head length, increased in the field where Larix kaempferi woodchip fertilizer was added as a basal dose. The result showed that the woodchip fertilizer made from Pinus koraiensis had faster releasing properties compared to other woodchip fertilizers. Without adding any compost in the woodchip fertilized field, woodchip fertilizer showed a superior outcome over a general chemical fertilizer. Although the amount of woodchip fertilizer was larger compared to that of a chemical fertilizer, it increased cabbage production.

The safranine impregnation differences in Pinus koraiensis, P. densiflora, P. rigida, and Larix kaempferi were studied. Among them, P. koraiensis conducted higher depth of safranine in radial and L. kaempferi in longitudinal direction. High magnification was used to observe the safranine penetration behavior in longitudinal direction especially in longitudinal tracheids. Safranine impregnation in longitudinal tracheids was captured in digital video mode to observe the formation of curved and flat air-safranine meniscus. Given the tracheid radius 16–20 μm, surface tension of water at 72 dynes per centimeter at 23°C and a contact angle 30°, the capillary pressure ranges from 0.06 to 0.08 bar. The lower the lumen diameter is, the higher the capillary pressure is. It was assumed that due to the differences of total water pressure under the safranine-water interface and total air pressure above the interface, curved meniscus was formed in the cell lumen.

This exploratory study evaluated the possibility of drying 50-mm-thick western red cedar with superheated steam. Since there are no industrial facilities in Canada drying western red cedar with superheated steam, the study was designed to explore the potential of this technology in terms of lumber quality, moisture content distribution, and drying time. The experiments showed that the 50-mm-thick product can be dried in less than three days without jeopardizing lumber quality (in comparison with the two weeks that is currently required in conventional kilns), and the percentage of pieces that remained wet after drying was within the 10% to 15% range that is typically tolerated in industry. Validerad; 2014; 20140319 (andbra)

Conventional chemical wood preservatives have been banned or restricted in some applications due to human and animal toxicity and their adverse impact on the surrounding environment. New, low-envir ...