Platysma muscle additionally innervated by a variant anterior branch of the great auricular nerve

Damage to the great auricular nerve, with consequent clinical deficits, is a common surgical complication in facial aesthetic and in head and neck procedures such as parotidectomy, neck dissection, rhytidectomy and platysma flap operations. Hence, a thorough knowledge of nerve anatomy, particularly its potential variations, is critical in reducing the associated operative morbidity. Accordingly, we report an unusual variation of the anterior branch of the great auricular nerve noted in an 81-year-old female cadaver. The nerve was observed to course into the submandibular region anterior and superficial to the internal jugular vein, communicating with the cervical branch of the facial nerve, while independently innervating the platysma muscle. Although several anatomical variations of the branches of the cervical plexus have been documented, our report describes unique innervation of the platysma muscle by the great auricular nerve, which provides a new insight on the motor component of the nerve

Densidad básica de la madera de Pseudotsuga menziesii (Mirb.) Franco en la Patagonia

In the Andean region of Patagonia, Argentina, in the provinces of Neuquén, Río Negro and Chubut, there are numerous Douglas Fir [Pseudotsuga menziesii (Mirb) Franco] plantations, which constitute one of the timber species most widely used in the region for commercial plantations. In this work, we studied Douglas Fir wood basic density and its variation within trees and among trees. Also, the relationship between wood density, ring-with and the proportion of latewood was examined by regression analysis, determining at the some time wood density of juvenile and mature wood. We found that mean wood density of Douglas Fir was 0,366 g/cm3, which is one of the lowest wood density values reported for this species elsewhere. Results show that rings-width and latewood proportion were significantly related to specific gravity. We also found that Douglas fir trees begun to produce mature wood at around 17 years of age.En la región andina de las provincias de Neuquén, Río Negro y Chubut de Argentina existen numerosas plantaciones de pino Oregón [Pseudotsuga menziesii (Mirb.) Franco], constituyendo una de las especies más utilizadas en plantaciones comerciales. En el presente trabajo se estudió la densidad básica de la madera de esta especie y su variación entre árboles y dentro de un mismo individuo, determinándose su relación con el ancho de anillos y la proporción leño temprano por medio de análisis de regresión. Paralelamente se determinó la densidad correspondiente a madera juvenil y madura. La densidad básica media para la población analizada fue de 0,366 g/cm3, valor que se encuentra entre los mínimos citados para diferentes lugares del mundo en los cuales se cultiva la especie. La densidad básica se correlacionó significativamente con el ancho de anillos y la proporción de madera tardía. Se encontró que la edad a partir de la cual se forma madera madura es 17 años

Diatomite – evaluation of physico-mechanical, chemical, mineralogical and thermal properties

Diatomite is one of the most intensively examined raw materials in the materials industry with a broad range of various applications. The diatomite sample, collected from Vitačevo plateau in the vicinity of Kavadarci, was fully characterized by means of physical-mechanical, chemical, XRPD, SEM, TEM, DTA/TGA and IR techniques. The physical-mechanical features pointed out to soft, light, white to gray rock with shell-like structure exhibiting compressive strength from 4.65–4.88 MPa in dry form, whereas the total porosity ranges 70–72% and the density is 2.06–2.09 g/cm3. The chemical analysis of the diatomite revealed that SiO2 content exceeds 91%. The results from the X-ray powder diffraction indicate predominant amorphous SiO2 phase associated with minor presence of crystalline quartz, muscovite, chlorites and plagioclase. The IR spectrum of the diatomite manifested characteristic bands for amorphous silica at 799 cm–1 and 1101 cm–1. DTA/TGA results display great thermal stability of the sample remaining amorphous up to 1050ºC whereas the SEM analysis determined the morphology, surface characteristics and the nanometric pores in the raw material. Thus, the studied diatomite is classified as a natural nanomaterial that is suitable for broad application in various construction materials, refractory ceramics, special oxide ceramics, and also finds potential use in filtering, adsorbent, catalysts, food and pharmaceutical industries

Fabrication of Ceramic Monoliths from Diatomaceous Earth: Effects of Calcination Temperature on Silica Phase Transformation

The raw diatomaceous earth from the vicinity of Bitola (North Macedonia) showed low bulk density (0.61–0.69 g/cm3), high-water absorption (75–81%) and porosity (66–72%). The chemical composition was determined with ICP-MS, revealing the following results for the diatomaceous earth: SiO2 (63.69 wt%), Al2O3 (11.79 wt%), Fe2O3 (5.95 wt%), MnO (0.15 wt%), TiO2 (0.65 wt%), CaO (1.51 wt%), MgO (2.24 wt%), P2O5 (0.13 wt%), K2O (1.64 wt%), Na2O (0.93 wt%), LOI (11.21 wt%). XRPD data of the examined sample of clayey diatomite mainly depicted crystalline behavior with a small presence of amorphous phase. The crystalline mineral phases mainly comprise: silica (quartz), feldspars (plagioclase), mica (muscovite), chlorites and dolomite. SEM and TEM results show cased presence of micro- and nanostructures with pores ranging from 250 to 600 nm. The clayey diatomite was sintered at three temperatures (900, 1000 and 1100ºC) for a period of 1 h. XRPD of the sintered samples at 1100ºC showed certain thermal stability and formation of new phases (mullite and tridymite) that makes the analyzed diatomaceous earth suitable for production of various types of ceramic, construction and thermal insulating materials

Impaired Inhibitory Control in Recreational Cocaine Users

Chronic use of cocaine is associated with impairment in response inhibition but it is an open question whether and to which degree findings from chronic users generalize to the upcoming type of recreational users. This study compared the ability to inhibit and execute behavioral responses in adult recreational users and in a cocaine-free-matched sample controlled for age, race, gender distribution, level of intelligence, and alcohol consumption. Response inhibition and response execution were measured by a stop-signal paradigm. Results show that users and non users are comparable in terms of response execution but users need significantly more time to inhibit responses to stop-signals than non users. Interestingly, the magnitude of the inhibitory deficit was positively correlated with the individuals lifetime cocaine exposure suggesting that the magnitude of the impairment is proportional to the degree of cocaine consumed

Postoperative complications in patients undergoing thyroid surgery

Background and objectives: Postoperative complications from thyroid surgery are numerous and may be shown on different levels. Some of these complications may be detrimental for patients, so minimization of the risks should be always considered. We evaluated the postoperative complications in patients after surgery of the thyroid gland at the Clinic for Thoracic Surgery, Skopje. Material and method: In retrospective manner, all patients undergoing thyroid surgery during the one-year period (1. January- 31. December 2017) were evaluated. Patients were divided into two groups, whereas group ST included patients who underwent goiter removal and subtotal thyroidectomy while group TT included patients in who total thyroidectomy was done. In both groups we analyzed the demographic data and the occurrence of postoperative (in the first 48 hours) complications (stridor, hoarseness, hemorrhage, nerve dysfunction, tracheomalacia, hypocalcemia and the need for reintubation and tracheostomy). Results: Total data from 197 patients was evaluated. 120 patients had subtotal thyroidectomy while total thyroidectomy had 77 patients. Postoperative complications occurred in significantly larger number of patients in the TT group (64.9 vs. 40%). Hoarseness (8.4% vs. 18.5%), stridor (18.3% vs. 9.2%) tracheomalacia (5% vs. 1.2%) and hematoma (2.5% vs. 3.8%) occurred in respect to the groups. Hypocalcaemia occurred in significantly larger number of patients in TT group. Permanent nerve injury was found in one patient in the same group and tracheotomy was done only in one patient. Conclusion: Overall results from our study show that the complications after thyroid surgery occur in all patients who undergo thyroid surgery. However, more severe complications and outnumbered are complications in patients who undergo total thyroidectomy. Key words: complications, occurrence, thyroid surgery, total thyroidectomy

Reduced Spontaneous Eye Blink Rates in Recreational Cocaine Users: Evidence for Dopaminergic Hypoactivity

Chronic use of cocaine is associated with a reduced density of dopaminergic D2 receptors in the striatum, with negative consequences for cognitive control processes. Increasing evidence suggests that cognitive control is also affected in recreational cocaine consumers. This study aimed at linking these observations to dopaminergic malfunction by studying the spontaneous eyeblink rate (EBR), a marker of striatal dopaminergic functioning, in adult recreational users and a cocaine-free sample that was matched on age, race, gender, and personality traits. Correlation analyses show that EBR is significantly reduced in recreational users compared to cocaine-free controls, suggesting that cocaine use induces hypoactivity in the subcortical dopamine system