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By exploiting recent developments associated with coupled microcavities, we introduce the concept of the PT-symmetric phonon laser with balanced gain and loss. This is accomplished by introducing gain to one of the microcavities such that it balances the passive loss of the other. In the vicinity of the gain-loss balance, a strong nonlinear relation emerges between the intracavity-photon intensity and the input power. This then leads to a giant enhancement of both optical pressure and mechanical gain, resulting in a highly efficient phonon-lasing action. These results provide a promising approach for manipulating optomechanical systems through PT-symmetric concepts. Potential applications range from enhancing mechanical cooling to designing phonon-laser amplifiers. [ABSTRACT FROM AUTHOR]

Wireless networks are susceptible to security attacks due to their open transmission media. Therefore, wireless network security is somewhat more complex than that of wired network security. In wireless network security, authentication is the most essential procedure to ensure that the service is properly used by the intended users. Protected Extensible Authentication Protocol (PEAP) is widely being used in wireless networks. However, PEAP is shown to be a weak protocol in terms of protection of user identity. In this paper, we have designed and implemented a new and efficient wireless authentication protocol providing user identity secrecy. This method takes advantage of PEAP's management easiness and the robustness of dynamic key distribution to provide user identity protection. [ABSTRACT FROM AUTHOR]

Objective:Mutations in the genes for connexin 26 (GJB2) and connexin 30 (GJB6) play an important role in autosomal recessive, non-syndromic hearing loss. This study aimed to detect the 35delG and 167delT mutations of the GJB2 gene and the del(GJB6-D13S1830) mutation of the GJB6 gene in paediatric patients diagnosed with congenital, non-syndromic hearing loss and treated with cochlear implantation in Mediterranean Turkey.Materials and method:We included 94 children diagnosed with congenital, non-syndromic hearing loss and treated with cochlear implantation. Blood samples were collected, DNA extracted and an enzyme-linked immunosorbent assay performed to enable molecular diagnosis of mutations.Results:Of the 94 children analysed, the 35delG mutation was detected in 12 (12.7 per cent): 10 (83.3 per cent) were homozygous and 2 (16.7 per cent) heterozygous mutant. The 167delT and del(GJB6-D13S1830) mutations were not detected.Conclusion:The GJB2-35delG mutation is a major cause of congenital, non-syndromic hearing loss in this study population. [ABSTRACT FROM PUBLISHER]

BACKGROUND: Evidence that long-term hormone therapy (HT) may increase the risk of serious adverse events led to a sharp reduction in all HT use, including short-term use for vasomotor symptom relief. We estimated women's willingness to accept adverse event risks in exchange for vasomotor symptom relief when risks are communicated in absolute vs. relative terms. METHODS: We developed a conjoint survey to elicit preferences across benefit and risk attributes of HT. The survey was administered via the Internet to 523 U.S. women aged 46-60 years. Participants evaluated pairs of hypothetical treatments and indicated preferences using a Likert-based scale. Risks were presented in absolute and relative terms. Satisfaction scores for HT risks and benefits were estimated using random-effects, ordered-probit regression. Maximum acceptable risk (MAR) was calculated as the increase in risk that reduces the satisfaction score for a given level of HT benefit to 0. RESULTS: For both risk versions, the least important attribute (smallest difference in satisfaction scores) was night sweat frequency; heart attack risk was the most important (largest difference in scores). Participants were more willing to accept risks in return for symptom relief when shown absolute vs. relative risks, although differences in MAR were statistically significant only for breast cancer risk. MARs for breast cancer and heart attack exceeded reported rates in most cases. CONCLUSIONS: Many women may be willing to accept risks to control vasomotor symptoms. However, describing risks in different, but technically equivalent, ways affects women's willingness to trade risks for benefits. [ABSTRACT FROM AUTHOR]

Aim: This study evaluated microleakage at the interface between various temporary restorative materials and existing amalgam or composite restorations, and dental tissues in previously restored teeth after partial removal of the restoration. Materials and Methods: The distal half of amalgam (Ag) and composite restorations (Co) in 45 teeth were removed, then filled with temporary restorative materials (IRM, Coltosal and CLIP). After thermal cycling, microleakage was measured microscopically as the penetration of basic fuchsine according to a four-unit-scale: The data were evaluated with Friedman and Kruskal-Wallis tests using Bonferroni correction (p<0.05). Results: In almost all groups except the Co-IRM and Ag-CLIP interface, lower microleakage values were observed in temporary restoration-permanent restoration interfaces compared to temporary restoration-tooth interfaces, For the Ag and Co groups except for the Ag-IRM-b interfaces, the highest microleakage values were observed with IRM for b and c interfaces followed by Coltosol and CLIP. Interestingly, although CLIP was a temporary restoration, CLIP-tooth interface (Ag-CLIP-c) values were lower than amalgam-tooth interface (Ag-CLIP-a) values. Conclusions: CLIP provided a better seal against microleakage at amalgam and especially composite interfaces, This material also provided a better seal against microleakage at the tooth tissue interface, The use of a resin based temporary restorative material over partially removed resin composite restorations could be beneficial in achieving better resistance to marginal leakage. [ABSTRACT FROM AUTHOR]

The X-ray observations of Cyg X-1, covering a period of 3.8 years, by the All Sky Monitor (ASM) on board the Rossi X-ray Timing Explorer (RXTE) were analysed to search for long periodicities. The periodicities in the original data were seen to be distorted by the high/soft state and the failed state counts of the system, and thus the power spectra showed two unrealistic peaks at 1608and 406 days. The ∼ 300 day modulation reported previously(e.g. Priedhorsky et al. 1983) is not confirmed by the present ASM data. Truncation of the high counts above 30 cnts/s partly eliminates the distortion and reveals the true period of 150d in the power spectra. It is interesting that the high/soft state (HS) and the failed state transitions (FST) always occur on the maximum phase of the150d cycle. [ABSTRACT FROM AUTHOR]

Late-onset neonatal sepsis has a high mortality rate in premature infants. To date, no single test in the evaluation of neonatal sepsis has been demonstrated to be both sensitive and specific enough to assist in timely decision making. The aim of our study is to develop a predictive model that can be applied to all premature babies, using clinical and laboratory findings in premature babies, to recognize late-onset neonatal sepsis.65 premature patients diagnosed with culture-proven late-onset neonatal sepsis and hospitalized in Dr. Behcet Uz Pediatric Diseases and Surgery Training and Research Hospital neonatal intensive care unit between January 2018 and December 2020, and 65 premature newborns of similar age and gender who did not have sepsis were included in the study retrospectively.In our study, feeding difficulties, worsening in clinical appearance and fever were found to be significant among clinical findings, while thrombocytopenia and high C-reactive protein among laboratory findings are the strongest data supporting late-onset neonatal sepsis. In multiple regression analysis, thrombocytopenia, mean platelet volume, C-reactive protein, lymphocyte count and feeding difficulties had the highest odds ratio (p <  0.05). By converting these data into a scoring system, a nomogram was created that can be easily used by all clinicians.In our study, we developed a scoring system that can be easily applied to all premature patients by evaluating the clinical and laboratory findings in late-onset neonatal sepsis. We think that it will help in recognizing late-onset neonatal sepsis and strengthening the treatment decision. Predicting the individual probability of sepsis in preterm newborns may provide benefits for uninfected newborns to be exposed to less antibiotics, not to be separated from mother and baby, and to reduce healthcare system expenditures. The nomogram can be used to assess the likelihood of sepsis and guide treatment decision. [ABSTRACT FROM AUTHOR]

Background: Protein-energy malnutrition (PEM) is associated with increased morbidity and mortality in haemodialysis (HD) patients. Insulin-like growth factor I (IGF-I) has proved to be a sensitive marker of malnutrition, while interleukin-1 (IL-1β) and tumour necrosis factor (TNF) have been found to be raised in catabolic states. [ABSTRACT FROM PUBLISHER]

The UBV observations of the massive binary BF Aur were made at the Ankara University Observatory during 1988, 1989 and 1996. Asymmetry of the light curves, arising from unequal height of successive maxima, indicates that the system is active. By analysing these observations in the framework of the Roche model (including the presence of bright regions on the components) one obtains a semidetached configuration of the system, with the cooler secondary component filling its Roche lobe. The analysis of the light curves yields consistent solutions for mass ratio q = m2/m1 somewhat less than one. The influence of the mass transfer on the change of the system-orbital-period is relatively small. The upward parabolic character of the O–C diagram (Zhang et al., 1993) indicates a mass transfer from the less massive secondary to the more massive primary. This inturn requires the less massive secondary to fill its Roche lobe. This is consistent with our solution. Based on these facts we introduced the following working hypothesis. At the place where the gas stream from the secondary falls on the primary, relatively small in size but a high temperature contrast active hot-spot (hs) region is formed. As a result of the heating effect caused by the irradiation of the hot-spot region, on the secondary's side facing the hot spot a bright-spot (bs) region is formed. The bright-spot region is larger in size but with significantly lower temperature than the hot spot. This region can be treated as a ‘reflection cap’. By analysing the light curves in the framework of this working hypothesis the basic parameters of the system and the active regions are estimated. The problem is solved in two stages: by obtaining a synthetic light curve in the case when the parameters of the corresponding Close Binary (CB) Roche model (Djurašević, 1992a) are given a priori (the direct problem) and by determining the parameters of the given model for which the best fit between the synthetic light curve and the observations is achieved (the inverse problem) (Djurašević, 1992b). [ABSTRACT FROM AUTHOR]

Familial Mediterranean fever (FMF) is a genetically transmitted disease characterized by recurrent attacks of fever and serositis. The most important complication of this disease is the development of amyloidosis. We present our analysis of 425 FMF patients without and 180 with amyloidosis (123 FMF having amyloidosis type I and 57 FMF having amyloidosis type II). The male/female ratio was higher in the amyloidosis population (111/69) when compared to the FMF population (225/200) (P = 0.048). Consanguinity rate was the same among FMF and amyloidosis groups. However, a family history of amyloidosis was significantly more frequent in the amyloidosis group (P = 0.00001). Multivariate analysis has revealed that in FMF patients, the presence of a family history of amyloidosis plus consanguinity has a 6.04 fold increased risk of amyloidosis (P < 0.0001). The 5-year chronic renal failure free survival was 43.1% and 18.7% in type I and type II amyloidosis, respectively. The time interval to develop chronic renal failure after the development of amyloidosis was 4.8 in type I and 3.0 years in type II, respectively. We found ten cases of Henoch-Schönlein Purpura and nine of polyarteritis nodosa among our patients. The significance of the association between FMF and vasculitis awaits to be clarified. Among the FMF patients put on colchicine therapy (435), only 10 (2.3%) have developed amyloidosis confirming that this drug protects from amyloidosis.Conclusion Since the presence of a familial history of amyloidosis has been defined as the most important risk factor in the development of amyloidosis, we suggest that additional genetic factors may be operative in the development of amyloidosis. [ABSTRACT FROM AUTHOR]

The present study in female rats determined the effects of experimental hyperthyroidsm on hemorheological parameters and fibrinogen concentration. To induce experimental hyperthyroidism l-thyroxine (0.4 mg/100 g fodder) was added to the fodder of the experimental group rats for 20 d. After experimental duration, T, T, and TSH levels, plasma and blood viscosity, hematocrit, erythrocyte rigidity index, and plasma fibrinogen concentration values of both the control and the experimental group animals were determined and evaluated. In the experimental group, T and T levels were higher and TSH levels lower than that of the control rats (respectively, p<0.01, p<0.001, p<0.001). Plasma viscosity and fibrinogen concentration of hyperthyroid group were found significantly higher than controls ( p<0.01). However there was no significant difference found in blood viscosity, hematocrit, and erythrocyte rigidity index between control and experimental groups. Thus, hyperthyroidism induced increased fibrinogen concentration can alter the rheological structure of blood by inducing increase in plasma viscosity. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the presence of peripheral antineutrophil cytoplasmic antibodies (p-ANCA) and cytoplasmic antineutrophil cytoplasmic antibodies (c-ANCA) in children with SLE and to correlate its association of laboratory findings. Twenty-one children with SLE were studied. Serum samples in patients were tested by indirect immuno-fluorescence (IIF) slide kit (INOVA) for c-ANCA and p-ANCA and by ELISA for myeloperoxidase (MPO-ANCA) and proteinase 3 (PR3-ANCA). All the patients but two were quiescent for lupus at the time of sampling Sixteen of 21 patients showed positive IIF staining whereas only 5 had MPO-ANCA and 2 of nine PR3-ANCA. The data suggests that SLE may be associated p-ANCA directed against additional target antigens rather than MPO and may be implicated in the pathogenesis of SLE or may be only non-specific antibodies developed in lupus. [ABSTRACT FROM AUTHOR]