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This study aims to eliminate the wall effect experienced in molded specimens by either sawing or drilling them out of concrete blocks. For this purpose, the concrete blocks were prepared in four different thicknesses: 50, 100, 150, and 200 mm (2, 4, 6, and 8 in.) and in two different strength classes: moderate and high. The maximum sizes of the aggregates used in the concretes were 12, 22, and 31.5 mm (0.47, 0.87, and 1.24 in.) for each concrete class. The cubic and core specimens were sawn or drilled out of concrete blocks with an equal length or diameter to the thickness of blocks. The damage that occurred during sawing or drilling was related to the maximum aggregate size of the concrete and, by using the size effect law, the damage was predicted. After eliminating the wall effect and the damage of sawing or drilling, it was observed that a considerable size effect exists between the specimens tested. [ABSTRACT FROM AUTHOR]

The article discusses the method used on the evaluation of concretes containing pozzolanic materials under the rapid chloride penetration test (RCPT). Benchmarking was used to evaluate the presence of fly ash, granulated blast-furnace slag and the silica fume as additives in the production of concrete. The RCPT was then applied over the air-stored and water-cured specimens within 90 days. A statistical experimental design method was also used to determine the values of the chosen variables, such as the binder content, pozzolanic material content and water-binder ratio (w/b). A total of 80 mixtures were obtained and tested under the curing condition. Moreover, it was evaluated that pozzolanic material content substantiates more than (w/b) on chloride permeability for water-cured concretes.

Macro-defect-free (MDF) cements are cement-polymer composites characterised by high tensile and flexural strength but serious durability problems were observed when these composite materials are in contact with water. In order to improve the water resistance, MDF cements were produced by addition of two types of self crosslinkable polymers. The aim of this study is to characterize the obtained MDF cements, by using contact angle measurements, FTIR spectroscopy and to correlate the results with the mechanical properties of the MDF cements in initial state and after their storage in water. [ABSTRACT FROM AUTHOR]

The effect of initial water-curing period on the strength properties of concretes was investigated. Three types of cement, one ordinary Portland cement (OPC) and two natural pozzolanic cements (blended and trass cements), were used in the concrete mixtures. Six different curing regimes were applied to the specimens, the first of which was continuous water storing, and the second continuous air storing. In the remaining four regimes, the specimens were stored under varying initial water-curing periods of 3, 7, 14, and 28 days, respectively. The compressive strength tests were carried out on the cubic specimens at the ages of 7, 14, 28, 90, and 180 days. The variation of compressive strength with time was evaluated by using a semilogarithmic function and the strength-gaining rates were calculated by using this equation for different curing conditions. It was found that poor curing conditions are more adversely effective on the strength of concretes made by pozzolanic cements than that of OPC, and it is necessary to apply water curing to the former concretes at least for the initial 7 days to expose the pozzolanic activity. However, when the pozzolanic cement concretes have sufficient initial curing, they can reach the strength of OPC concretes in reasonable periods of time. [Copyright &y& Elsevier]

Nasal skin quality is an essential indicator of rhinoplasty outcomes. The objective of this study was to collect data on the nasal skin thickness of randomly selected Turkish men and women. The study involved 50 male and 50 female subjects. We measured the nasal dorsal skin thickness by pinching the sides of the nose upwards to produce a skinfold and then measuring the thickness of this skinfold with a Castroviejo caliper [A&A, Almecon Instruments]. We also measured the thickness of the right and left alar walls with the same caliper. In the male subjects, the mean nasal dorsal thickness and the mean overall, right, and left alar wall thicknesses were 4.02 ± 0.71, 3.99 ± 0.69, 3.98 ± 0.69, and 4.00 ± 0.69 mm, respectively. The corresponding values in the female subjects were 3.38 ± 0.56, 3.45 ± 0.66, 3.43 ± 0.67, and 3.46 ± 0.65 mm. In Turkish men, a nasal dorsum measuring greater than 4 mm can be considered "thick." In Turkish women, the mean nasal dorsal and alar wall thicknesses were 3.38 and 3.45 mm, respectively. Values greater than these are considered "thick." Either nasal dorsal thickness or alar wall thickness may be measured in men, but both must be measured in women scheduled to undergo rhinoplasty. Dark nasal skin and oily nasal skin tend to be thicker.

Remains of fossil hominins from temperate regions of the Old World are rare across both time and space, but such specimens are necessary for understanding basic issues in human evolution including linkages between their adaptations and early migration patterns. We report here the remarkable circumstances surrounding the discovery of the first fossil hominin calvaria from Turkey. The specimen was found in the Denizli province of western Turkey and recovered from within a solid block of travertine stone as it was being sawed into tile-sized slabs for the commercial natural stone building market. The new specimen fills an important geographical and temporal gap and displays several anatomical features that are shared with other Middle Pleistocene hominins from both Africa and Asia attributed to Homo erectus. It also preserves an unusual pathology on the endocranial surface of the frontal bone that is consistent with a diagnosis of Leptomeningitis tuberculosa (TB), and this evidence represents the most ancient example of this disease known for a fossil human. TB is exacerbated in dark-skinned peoples living in northern latitudes by a vitamin D deficiency because of reduced levels of ultraviolet radiation (UVR). Evidence for TB in the new specimen supports the thesis that reduced UVR was one of the many climatic variables presenting an adaptive challenge to ancient hominins during their migration into the temperate regions of Europe and Asia., ((c) 2007 Wiley-Liss, Inc.)

The quantitative structure-property relationship (QSPR) model was developed for the 50% effective inhibition concentration (48h - EC(50)) of 36 selected substituted benzenes for the algae Scenedesmus obliquus by the application of the Characteristic Root Index (CRI) model. To increase the predictive power of the CRI-based model, the following semi-empirical molecular descriptors calculated by the quantum chemical PM3 method were included: the energy of the highest occupied molecular orbital (E(HOMO)), the energy of the lowest unoccupied molecular orbital (E(LUMO)), and the dipole moment (mu). A two-descriptor model with a correlation coefficient of r=0.926 was developed without the outliers from multiple regression analysis [-logEC(50)=0.494 (+/-0.072) CRI-0.798 (+/-0.063) E(LUMO)+1.985 (+/-0.169)]. E(LUMO) was the most important parameter, followed by the CRI. E(LUMO) reflects electronic properties, whereas the CRI reflects hydrophobicity, molecular size, and branching. The statistical robustness of the developed model was validated by the modified jackknife test. The predictive accuracy of the proposed model was compared with the recently published study in which a toxicity model was developed for the same algae. Because of its high statistical significance, the validated model has been used to predict -logEC(50) values of compounds for which there are no experimental measurements.

Objectives: We investigated arterial blood gas abnormalities in patients presenting with dizziness., Patients and Methods: The study included 58 patients (39 females, 19 males; mean age 46 years; range 22 to 74 years) who presented during attacks of dizziness. The duration of vertigo complaints ranged from one day to 30 years. Arterial gas measurements were performed at presentation and one month after treatment. The patients were examined in five groups according to the diagnoses: Meniere's disease (n=14), benign paroxysmal positional vertigo (n=13), vertebrobasilar insufficiency (n=12), vestibular neuritis (n=4), and craniocervical myofascial syndromes (n=15)., Results: At presentation, pH was low (acidosis) in two patients (3.5%), and high (alkalosis) in 15 patients (25.9%). After treatment, all abnormal pH values returned to normal. Twenty-four patients had high or low HCO3- values. High HCO3- values persisted in three patients together with dizziness. Patients with vestibular neuritis had significantly higher PO2 values compared to those with craniocervical myofascial syndrome and vertebrobasilar insufficiency (p<0.05). However, one month after treatment, there were no significant differences between five groups with respect to PO2 levels (p>0.05). Consecutive blood gas measurements did not differ significantly within each diagnosis group (p>0.05)., Conclusion: Our results suggest that arterial blood gas abnormalities may be related to vertigo attacks.

Objectives: The aim of surgery for choanal atresia is to remove the atretic plate completely and to assure long-term patency. We evaluated the effectiveness and results of endoscopic transnasal approach in the treatment of choanal atresia., Patients and Methods: The study included eight patients (1 male, 7 females; mean age 25.8 years; range 17 to 53 years) who were treated with endoscopic transnasal approach for choanal atresia. One patient had bilateral involvement. The diagnosis was based on findings of physical examination, endoscopic examination, and computed tomography. The follow-up period ranged from 10 months to four years., Results: Only one patient developed partial obstruction which was reconstructed with mushroom-head forceps at a subsequent operation. One patient died from primary disease (nasopharyngeal cancer). The remaining patients became symptom-free., Conclusion: Endoscopic transnasal approach for the treatment of choanal atresia is a safe procedure, with a high success rate and low morbidity, enabling detailed evaluation of the anatomic structure.

QSPR models for water solubility (S), n-octanol/water partition coefficient (K(OW)), and Henry's law constant (H) for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzo-p-furans (PCDFs) and phthalates have been established based on two different sets of parameters. Those parameters were topology based characteristic root index (CRI) and three semi-empirical molecular descriptors, namely--energies of the highest occupied and the lowest unoccupied molecular orbital (E(HOMO) and E(LUMO)), and dipole moment (mu). The best fit equation found by "forward multiple linear regression" showed that the topology based CRI was the most important parameter for the modelling of solubility and n-octanol/water partition coefficient. For n-octanol/water partition coefficient a two-parameter equation including the CRI and E(HOMO) with a correlation coefficient of r = 0.992 was obtained whereas a three-parameter equation for solubility and Henry's law constant including the CRI, E(LUMO) and mu with a correlation coefficient of r = 0.986 and r = 0.933 was obtained, respectively. E(HOMO) and mu didn't appear in the same model because of the collinearity. The results of modified jackknife tests indicated that the three models were statistically robust. Mean deviation of calculated values from experimental data amounted to 0.27, 0.17, and 0.28 log units for the three properties mentioned. The developed models have been used to predict the S, K(OW) and H of compounds not included in the training sets.

Rhinoplasty is a collection of surgical procedures performed on nose for the purpose of correcting functional and shape deformities. Nose is a facial feature which naturally draws attention during everyday contact. Any operation performed on nose has to blend well with the other facial features of the face. For this reason rhinoplasty is a type of surgery which requires artistic skills from surgeon as well as surgical skills. In this paper we present an artistic simulation tool which manipulates the shape of the nose on the bases of rhinoplasty procedures to be used during the surgery. Unlike other artistic simulation tools which can modify shape with no constraints, this tool simulates the effect of individual operations. Simulation tool can be valuable only if it predicts the outcome of the surgery with accuracy. Ultimately the outcome of the simulation depends largely on the experience of the surgeon. This is also the case with the tool presented in this study, so with experience the tool can be useful for predicting outcome more and more accurately. In this paper, the mechanical model of the nose and tools used for simulation are discussed. The simulation results are compared with actual rhinoplasty results to see the fidelity of the approach. A flowchart of the decision process and how rhinoplastic simulation together with the ideal nose data can be used to aid actual rhinoplastic surgery is given at the end.

Several problems have been observed when performing the classic endoscopic technique for voice restoration following laryngectomy. An easy and safe method is described for the insertion of a Provox voice prosthesis using a Yankauer tonsil suction tube and an antrum trocar with an irrigation cannula.

Intussusception occurs rarely in adults. It presents with a variety of acute, intermittent, and chronic symptoms, thus making its preoperative diagnosis difficult. In adults, intussusceptions are mostly caused by organic lesions and the majority of these lesions are benign tumours. Computed tomography scanning and endoscopy have proved to be the most useful diagnostic methods. Confirmation of diagnosis and treatment of adult intussusception is surgical, with surgical resection of the intussusception without reduction being the preferred treatment in adults, as almost half of both colonic and enteric intussusceptions are associated with malignancy. We report the case of a patient with ileocolic intussusception due to an ileal lymphoma.

Many studies have revealed the frequency of p53 abnormalities in lung cancer. However, clinico-pathological studies of p53 abnormalities have yielded conflicting results. We examined the p53 immunoreactivity and studied the correlations of p53 status and clinicopathological parameters in 76 primary lung cancers. By using DO-7 antibody, different degrees of p53 immunoreactivity was detected in 8 of 30 small cell lung cancer (SCLC, 26.6%) and 22 of 46 non-small cell lung cancer (NSCLC, 47.8%), 6 of 19 adenocarcinoma, 16 of 27 epidermoid carcinoma cases. In the whole group, no correlation was detected between the p53 status and the histological types of tumor, local tumor invasion, nodal status, and distant metastasis and patient characteristics, such as age, gender or smoking habit. P53 status was also found to have no effect on survival. However, in the NSCLC group, there was a significantly higher p53 immunoreactivity in well- and moderately-differentiated tumors (p<0.05). Patients with p53 immunoreactivity had a poor therapeutic response in the whole group. We concluded that, although p53 immunreactivity may be found in NSCLC, this does not correlate with clinicopathological parameters except therapeutic response. In SCLC p53 immunreactivity can be negligible.

Histoplasmosis, a disease endemic to North America, is caused by Histoplasma capsulatum. To the best of our knowledge, the chronic cavitary pulmonary histoplasmosis patient described here presents the first case in which the fungus was isolated from sputum culture in Turkey.

In this study, 41 cases of cerebral abscess operated on in our clinics between 1977 and 1986 were investigated retrospectively. The surgical strategy and the factors affecting the mortality rate were discussed. It was confirmed that the most important factor affecting the mortality rate was the consciousness level of patients in the preoperative period. The importance of computed tomography (CT) for early diagnosis and management of brain abscess is stressed.