Abstract Objective: The COVID-19 pandemic adversely affects the mental health of vertigo patients. Thus, this study aimed to investigate the effects of coronavirus anxiety, health anxiety, anxiety symptom levels, and demographic variables on vertigo and its severity in vertigo patients during the pandemic. Methods: This cross-sectional study was conducted from May 15 to November 15, 2021. In total, 118 patients with vertigo and 82 healthy controls participated in the study. Besides demographic and clinical data, Coronavirus Anxiety Scale (CAS), Hospital Anxiety Depression Scale-Anxiety Subscale (HAD-A), and Short Health Anxiety Inventory (SHAI) were applied to all participants. Additionally, Vertigo Symptom Scale-Short Form (VSS-SF) was administered to vertigo patients. Results: According to the findings, vertigo patients experienced higher levels of coronavirus anxiety, health anxiety, and anxiety disorder compared to the healthy controls. In vertigo patients, the rate of coronavirus anxiety was 20.3%, and the rate of anxiety disorder was 32.2%. Majority of the patients (80.5%) were found to have severe-level vertigo. Additionally, most of the patients (82.1%) reported that the severity of vertigo during the pandemic was higher than before the pandemic. Conclusion: The COVID-19 pandemic causes serious mental health problems in vertigo patients, and pathological levels of these problems increase the discomfort of vertigo. Therefore, psychological assessment should be considered in these patients, and required psychological support and guidance services should be provided.

Abstract: Turkish hazel (Corylus colurna) lumber with a nominal thickness of 5 cm from the Kastamonu region, Turkey, was dried through conventional kiln drying using two different programs, a non-protective drying schedule and a protective drying schedule. The goal of the study was to obtain a kiln schedule that would maintain wood quality and also save drying time until a final moisture content of 8 ± 2% was reached. The intensity of warping (twisting, bowing, cupping, crooking), superficial, internal, and end checks, residual stresses, drying rate, and moisture gradient of the dried woods were measured, and the results were evaluated according to the classification of the European Drying Group. The results showed a more homogeneous moisture profile, fewer occurrences of superficial checks, and an absence of internal checks when using the protective drying schedule due to low warping values compared with those for the non-protective drying schedule. From the point of view of energy efficiency, by saving 60 h of drying time, the non-protective schedule reduced electricity by 960 KWh and was therefore more profitable by $105,60 in this trial. Therefore, it seems that the protective drying schedule should be recommended as the optimum program for drying Turkish hazel lumber from the Kastamonu region at the commercial scale.

The aim of this study is to determine the change of some physical properties (oven-dry density, weight loss, swelling and anti-swelling efficiency) and mechanical properties (compression strength parallel to grain, bending strength, modulus of elasticity in bending, janka-hardness (cross-section, radial, tangential), impact bending strength and tension strength perpendicular to grain) of wild cherry woods after heat treatment under different durations. Specimens are exposed to temperature levels of 212°C for time spans of 1,5 and 2,5 h. Based on the findings in this study, the results showed that oven-dry density, swelling, compression strength parallel to grain, bending strength, modulus of elasticity in bending, janka-hardness (Cross-section, Radial, Tangential), impact bending strength and tension strength perpendicular to grain values decreased with increasing treatment time.

World production of wood based panel has grown from 63,1 million cubic meters in 2005 to 75,5 million m³ in 2009, a 12 million m³ rise in production. China is the world's largest wood based panel’s manufacturer. The Turkish wood based panels industry has shown a tendency of fluctuating during this time. Turkey, as the world’s 4th largest producer of wood based panels, is an important contributor to the industry. Turkey has made great strides in the last 20 years in the forest products industry. Both the development of new materials and techniques of domestic and international market demand have played a decisive role. Turkey's wood panel production has gone from 100000 m³ in the early 2000s, to 5,5 million m³ of production in 2010. The sector's total production capacity is approximately 9 million m³. The results obtained thus far indicate that the Turkish wood based panel industry demand for raw material is not being met by the GDF's chip wood fiber production. Where the raw material supply problem in the industry, as well as the problems encountered in the forest and on the basis of the villagers living adjacent to, not to the time of product problems related to storage and transportation of raw materials and other related problems are bottlenecks. We examine problems related to the provision of raw materials and raw materials research, the need for future estimates of the level at which the world and close to the periphery countries will be examined, wood composite panel production and trade policy recommendations will be developed.

Wild cherry wood (Cerasus avium (L.) Monench) lumber with a nominal thickness of 5 cm from Duzce region in Turkey was dried through conventional kiln drying using two different programs which are unprotective drying schedules, and protective drying schedules. The aim was to obtain the most desirable kiln schedule for keeping the wood quality at an appropriate level up to final moisture content of 12±2% was reached. Intensity of warping (twist, bow, cup, crook) occurrence, superficial, internal and end checks, residual stresses, drying rate, and moisture gradient in the dried woods were measured, and the results were analyzed. The results showed that there was a more homogeneous moisture profile, fewer occurrences of superficial checks, and absence of internal checks in the protective drying schedules due to low warping values compared to the unprotective drying schedules. Therefore, it seems that protective drying schedules might be recommended as optimum program for wild cherry lumber drying at commercial scale from Duzce region.

Wettability and surface roughness properties of medium density fiberboard (MDF) panels made from Rhododendron biomass were examined in this study. Rhododendron dominates the understory layer of the forests throughout the Black Sea Region in Turkey with substantial biomass potential. This study was conducted to evaluate suitability of Rhododendron fiber for MDF production. For the experiments, rhododendron and commercially-manufactured-chip (Pinus sylvestris L. and Quercus robur L.) with 11% moisture content were used. The mixing ratios of rhododendron with commercially-manufactured-chip were 100:0, 75:25, 50:50, 25:75 and 0:100 %, respectively. Commercial urea formaldehyde (UF) adhesive was used as a binder. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements by the stylus method were taken perpendicularly to the fiber. There was a significant difference (p=0.05) between surface roughness parameters (Ra, Rz, Rq, and Ry). The results obtained in this study revealed that all the panels have met the general purpose-use requirements of European Norm (EN). It was found that panels made with a 25/75 ratio of rhododendron to commercially-manufactured-chip had a significantly lower contact angle (88.14º) than panels made with a 100/0 ratio (117.91º). Surface roughness measurements are based on four roughness parameters, average roughness (Ra), mean peak-to-valley height (Rz), root mean square roughness (Rq), and maximum peak-to-valley height (Ry) were considered to evaluate the surface characteristics of the panels and supported the above findings as the panels made with a 25/75 ratio had a slightly rougher surface with average values of 2.929 ìm (Ra). From the tests performed, we conclude that increasing the rhododendron mixing portion increased surface roughness and decreased wettability. Based on these results, rhododendron biomass could be an alternative raw material for MDF manufacturing.