24 results on '"Sohrabi S"'
Search Results
2. Ion beam-based coincidence Doppler broadening spectroscopy of positron annihilation radiation: The experiences of Tehran Van de Graaff lab
- Author
-
Biganeh, A., Rafi-Kheiri, H., Sohrabi, S., and Yadollahzadeh, B.
- Published
- 2022
- Full Text
- View/download PDF
3. Continuous and ultra-fine grained chip production with large strain machining
- Author
-
Kanani, M., Sohrabi, S., Ebrahimi, R., and Paydar, M.H.
- Published
- 2014
- Full Text
- View/download PDF
4. Mechanical properties and deformation behavior of Al/Al7075, two-phase material
- Author
-
Sherafat, Z., Paydar, M.H., Ebrahimi, R., and Sohrabi, S.
- Published
- 2010
- Full Text
- View/download PDF
5. The impact of completion thyroidectomy.
- Author
-
Sawant, R., Hulse, K., Sohrabi, S., Yeo, J.C.L., Pal, K., Gibb, F.W., Adamson, R., and Nixon, I.J.
- Subjects
IODINE isotopes ,ELECTRONIC health records ,INJURY complications - Abstract
The oncological benefit of completion thyroidectomy (CT) following thyroid lobectomy (TL) is presumed to be similar to that of upfront total thyroidectomy(TT), from a patient's perspective the risk and inconvenience of further surgery adds significantly to the impact of the overall treatment. The aim of this study is to assess the impact of CT in terms of the duration of admission and associated complications. A study of consecutive patients with DTC identified from prospective MDT records of South-East Scotland from 2009 to 2015. Surgical data was extracted from electronic medical record. Of 361 patients diagnosed with DTC, 161 (45%) had CT. The median postoperative stay was 1 day (range 1–5days). In total 22 patients (14%)suffered complications. Four patients (3%) developed postoperative haematoma. Two (1%) had an identified permanent nerve palsy on the completion side. 13 patients (8%) remained on calcium supplementation for more than 6 months postoperatively and three patients (2%) developed wound complications. Our study confirms that CT is regularly performed (45%). Recent changes in international guidelines recognize increasing number of patients as eligible for a conservative approach but recommend CT based on whether upfront TT would have been recommended if the TL pathology were known from the outset. Such an approach fails to consider the additional risk and inconvenience of CT on the overall patient experience. Due to a relatively high rate of complications, only those patients who are most likely to benefit from further surgery to facilitate adjuvant radioactive iodine should be offered additional surgery. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
6. On Sinc discretization for systems of Volterra integral-algebraic equations.
- Author
-
Sohrabi, S. and Ranjbar, H.
- Subjects
- *
DISCRETIZATION methods , *VOLTERRA equations , *INTEGRAL equations , *MATHEMATICAL physics , *ALGEBRAIC equations , *ITERATIVE methods (Mathematics) - Abstract
Abstract Integral-algebraic equations (IAEs) are coupled systems of Volterra integral equations of the first and second kind which naturally arise in many applications in mathematical physics. In this paper, we solve the IAEs of index-1 by Sinc-collocation discretization and prove that the discrete solutions converge to the true solutions of the IAEs exponentially. The discrete solutions are determined by linear systems which can be effectively solved by suitable iteration methods. Numerical examples are given to illustrate the effective performance of our method. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
7. Convergence analysis of the Jacobi-collocation method for nonlinear weakly singular Volterra integral equations.
- Author
-
Sohrabi, S., Ranjbar, H., and Saei, M.
- Subjects
- *
STOCHASTIC convergence , *JACOBI method , *INTEGRAL equations , *COLLOCATION methods , *VOLTERRA equations - Abstract
In this work, we present an efficient spectral-collocation method for numerical solution of a class of nonlinear weakly singular Volterra integral equations. This type of equations typically has a singular behavior at the left endpoint of the interval of integration. For overcoming this non-smooth behavior, we apply the Jacobi-collocation method. The convergence analysis of the proposed method is investigated in the L ∞ and the weighted L 2 norms and the results of several numerical experiments are presented which support the theoretical results. The computed results are compared wherever possible with those already available in the literature. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
8. Effects of environmental factors on Cucumis melo L. subsp. agrestis var. agrestis (Naudin) Pangalo seed germination and seedling emergence.
- Author
-
Sohrabi, S., Ghanbari, A., Mohassel, M.H.R., Gherekhloo, J., and Vidal, R.A.
- Subjects
- *
EFFECT of environment on plants , *MUSKMELON , *INVASIVE plants , *GERMINATION , *FLOODS , *WEED competition - Abstract
Cucumis melo L. subsp . agrestis var. agrestis (Naudin) Pangalo (wild melon) is an invasive plant in many parts of Asia and North America. The reproduction of this species is by seeds, thus laboratory experiments were conducted in order to determine the cardinal temperatures and the effects of fluctuating temperature, heat, flooding stress, pH, seed longevity, and depth of burial on wild melon seed germination and seedling emergence. Of the three models tested, the intersected lines model best estimated the cardinal temperatures. The base, optimum, and maximum temperatures for wild melon seed germination were estimated as 20, 35, and 45 °C, respectively. The highest germination rates of wild melon were obtained at 30/20 °C and 35/25 °C (day/night). Only long exposure periods (up to 10 days) at 90 °C or greater than 5 min at 120 °C were efficient at reducing the germination of wild melon seeds. Flooding had limited impact on reducing wild melon seed germination until the third month after the treatment. The seeds of this weed germinated across a wide range of pH values, but germination rates were higher under acidic (pH 5) rather than basic (pH 8 and 9) conditions. Seed germination of wild melon, declined to 50% by the 23rd month after burial in the soil at 15 cm depth. Emergence of wild melon seedlings was higher at shallower burial depths than at deeper ones. These results suggest that the successful invasion of wild melon in an area can be explained, in part, by its tolerance to a wide range of environmental conditions. The combination of seed longevity, lack of seed dormancy and rapid seed germination under favourable climatic conditions may explain its rapid establishment as a weed in summer crops. Among the management strategies that can be used to limit the infestation of wild melon in the fields, burying seed deeply during soil preparation seems to be the most promising. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
9. The Effects of Hotspot Detection and Virtual Machine Migration Policies on Energy Consumption and Service Levels in the Cloud.
- Author
-
Sohrabi, S. and Moser, I.
- Subjects
VIRTUAL machine systems ,CLOUD computing ,COMPUTER simulation ,ENERGY consumption ,COMPUTER scheduling - Abstract
Managing Cloud resources efficiently necessitates effective policies that assign applications to hardware in a way that they require the least resources possible. Applications are first assigned to virtual machines which are subsequently placed on the most appropriate server host. If a server becomes overloaded, some of its virtual machines are reassigned. This process requires a hotspot detection mechanism in combination with techniques that select the virtual machine(s) to migrate. In this work we introduce two new virtual machine selection policies, Median Migration Time and Maximum Utilisation, and show that they outperform existing approaches on the criteria of minimising energy consumption, service level agreement violations and the number of migrations when combined with different hotspot detection mechanisms. We show that parametrising the the hotspot detection policies correctly has a significant influence on the workload balance of the system. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
10. Glass transition kinetics and fragility of ZrCuAlNi(Nb) metallic glasses.
- Author
-
Sohrabi, S. and Gholamipour, R.
- Subjects
- *
GLASS transitions , *METALLIC glasses , *ACTIVATION energy , *X-ray spectroscopy - Abstract
The kinetics of glass transition and the fragility of Zr 55 Cu 30 Al 10 Ni 5 and (Zr 55 Cu 30 Al 10 Ni 5) 98 Nb 2 metallic glasses were investigated by the calorimetric measurements. The Nb minor addition narrows the width of glass transition, accelerates the relaxation process during glass transition, and decreases the energy barrier of glass transition. In addition, the fragility was evaluated in terms of the kinetic fragility index. While both alloys can be classified as intermediate glass formers, the Nb minor addition remarkably decreases the fragility and a stronger glass is achieved by the microalloying process. The lower fragility in the Nb-containing alloy is accompanied by higher degree of short-range ordering inferred from structural characterizations, formation of nanoscale chemical heterogeneities evidenced from the energy-dispersive X-ray spectroscopy (EDS) results, and deteriorated plasticity evaluated from the bending experiments. Our results highlight positive correlations between the fragility and the plasticity of the studied glasses. [Display omitted] • Glass transition kinetics and fragility of Zr 55 Cu 30 Al 10 Ni 5 and (Zr 55 Cu 30 Al 10 Ni 5) 98 Nb 2 metallic glasses were studied. • The activation energy of glass transition as well as the width of glass transition decrease by Nb addition. • Nb-containing alloy is a stronger glass former and has considerably smaller values of the kinetic fragility index. • Nb minor addition introduces nanoscale chemical heterogeneities. • Correlations between fragility and plasticity were observed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
11. Numerical solution of nonlinear Volterra integral equations of the second kind by using Chebyshev polynomials
- Author
-
Maleknejad, K., Sohrabi, S., and Rostami, Y.
- Subjects
- *
EQUATIONS , *POLYNOMIALS , *FUNCTIONAL analysis , *CHEBYSHEV series - Abstract
Abstract: Orthogonal Chebyshev polynomials are developed to approximate the solutions of linear and nonlinear Volterra integral equations. Properties of these polynomials and some operational matrices are first presented. These properties are then used to reduce the integral equations to a system of linear or nonlinear algebraic equations. Numerical examples illustrate the pertinent features of the method. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
12. Numerical solution of Fredholm integral equations of the first kind by using Legendre wavelets
- Author
-
Maleknejad, K. and Sohrabi, S.
- Subjects
- *
NUMERICAL analysis , *FUNCTIONAL analysis , *FUNCTIONAL equations , *MATHEMATICAL analysis - Abstract
Abstract: An efficient method based on the Legendre wavelet approach is proposed for approximate the solution of Fredholm integral equations of the first kind. The continues Legendre wavelets constructed on [0,1] are utilized as a basis in Galerkin method to reduce the solution of linear integral equations to a system of algebraic equations. For solving this system, we use the CG method. Furthermore, we suggest a convergence analysis and error estimation for this method. For showing efficiency of method some test problems, for which the exact solution is known, are considered. [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
13. Application of 2D-BPFs to nonlinear integral equations
- Author
-
Maleknejad, K., Sohrabi, S., and Baranji, B.
- Subjects
- *
INTEGRAL equations , *VOLTERRA equations , *NUMERICAL solutions to nonlinear evolution equations , *ERROR analysis in mathematics , *STOCHASTIC convergence , *NUMERICAL analysis , *MATHEMATICAL analysis - Abstract
Abstract: In this study, an efficient method is presented for solving nonlinear two-dimensional Volterra integral equations (VIEs). Using piecewise constant two-dimensional block-pulse functions (2D-BPFs) and their operational matrix of integration, two-dimensional first kind integral equations reduce to a lower triangular system. The rate of convergence and error analysis are given and numerical examples illustrate efficiency and accuracy of the proposed method. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
14. Prominent role of chemical heterogeneity on cryogenic rejuvenation and thermomechanical properties of La–Al–Ni metallic glass.
- Author
-
Sohrabi, S., Ri, M.C., Jiang, H.Y., Gu, L., Wen, P., Sun, Y.H., and Wang, W.H.
- Subjects
- *
THERMOMECHANICAL properties of metals , *METALLIC glasses , *HETEROGENEITY , *ACRYLONITRILE , *THERMOCYCLING - Abstract
Structural heterogeneity of metallic glass is critical in cryogenic rejuvenation but chemical heterogeneity is seldom explored. Here we show that cryogenic rejuvenation of a nominal La 60 Al 25 Ni 15 (at.%) metallic glass can be enabled with little impurities of Ce and Fe inside the material. Besides, these impurities can significantly enlarge the plastic strain conveyed by the material in bending. In addition, the heterogeneous structure is observed in the sample containing these chemical heterogeneities. Although the glass forming ability of the metallic glass is worsened, our study highlights the impact of chemical heterogeneity on the cryogenic rejuvenation of metallic glasses. Image 1 • The importance of chemical heterogeneity on cryogenic rejuvenation of metallic glasses. • A little impurity can enable energy-increase in La 60 Al 25 Ni 15 (at.%) metallic glass. • Plasticity-enhancement of rejuvenated glass. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
15. Diabetic Donors as a Source of Non–Heart-Beating Renal Transplants
- Author
-
Sohrabi, S., Navarro, A., Wilson, C., Sanni, A., Wyrley-Birch, H., Anand, V., Reddy, M., Rix, D., Jacques, B., Manas, D., and Talbot, D.
- Subjects
- *
KIDNEY transplantation , *ENDOCRINE diseases , *BRAIN stem , *TRANSPLANTATION of organs, tissues, etc. - Abstract
Abstract: Due to the organ shortage, many renal transplantation centers attempt to increase the donor pool by using non–heart-beating donors (NHBDs). These kidneys are generally regarded as “marginal” grafts. Many centers do not consider transplantation from an NHBD with a history of diabetes as it is a more suboptimal donor. We began our NHBD program in 1998 and have performed 5 renal transplants from diabetic NHBDs. Viability testing identified kidneys suitable for single or dual transplantation. Although kidneys from brain stem dead donors with diabetes have been used successfully, our data suggested that kidneys from diabetic NHBDs can also be used although we still need long-term results. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
16. Renal Graft Function After Prolonged Agonal Time in Non–Heart-Beating Donors
- Author
-
Sohrabi, S., Navarro, A., Wilson, C., Asher, J., Sanni, A., Wyrley-Birch, H., Vijayanand, D., Reddy, M., Rix, D., Jacques, B., Manas, D., and Talbot, D.
- Subjects
- *
URINARY organs , *ORGAN donation , *ABDOMEN , *TRANSPLANTATION of organs, tissues, etc. - Abstract
Abstract: To deal with the increasing gap between organ demand and supply for kidney transplantation, many centers have started to use non–heart-beating (NHB) donors. When we initiated our program to utilize kidneys from such donors in 1998, we had no protocol for the maximal agonal period. This however was audited in retrospect. Our current wait time is now a maximum of 5 hours. Concern has been expressed in the past about possible deterioration in the quality of the organs with a protracted agonal time. We aimed in this study to examine the effect of prolonging agonal period on the quality of kidneys retrieved from Maastricht category III donors: A total of 40 kidneys were transplanted from 29 category III donors between 1998 and 2004. Eleven kidneys had donor agonal times of >5 hours; the remainder, agonal times <5 hours. Both groups were matched for donor and recipient factors. The mean glomerular filtration rates at 12 months for <5 hours versus >5 hours agonal time were 43.8 ± 4.4 versus 49.8 ± 5.8, respectively (P = .24) and at 24 months, 46.83 ± 8.99 versus 37.67 ± 3.85, respectively (P = .24). In conclusion, intermediate graft function is comparable to ones with shorter agonal time, although we await long-term results. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
17. Dual Renal Transplantation for Kidneys From Marginal Non-Heart-Beating Donors
- Author
-
Navarro, A.P., Sohrabi, S., Wyrley-Birch, H., Vijayanand, D., Wilson, C., Sanni, A., Reddy, M., Manas, D., Rix, D., and Talbot, D.
- Subjects
- *
KIDNEY transplantation , *URINARY organs , *ISCHEMIA , *NON-heart-beating organ donation - Abstract
Abstract: Kidneys transplanted from non-heart-beating donors (NHBD) are generally regarded as marginal or extended criteria grafts due to the associated period of warm ischemia. The most prolonged periods occurring in the category II (uncontrolled) donor. This potential for injury can adversely affect the glomular filtration rate (GFR), which in severe cases results in primary nonfunction. Viability testing can identify a group of kidneys that, although unsuitable for solitary transplantation, may be considered for dual transplant. This retrospective study examined a series of 11 dual renal transplants, comparing 3- and 12-month GFR outcome data with 81 single NHBD transplants. The mean GFR at 3 months in the dual group was 47.6 and at 12 months was 48.6. In the single group the GFR at 3 months was 40.6 and at 12 months was 41.9. Thus using viability testing to identify NHBD kidneys suitable for dual transplant appears reliable and predictable. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
18. Renal Transplants From Category III Non-Heart-Beating Donors With Evidence of Pre-Arrest Acute Renal Failure
- Author
-
Navarro, A.P., Sohrabi, S., Wilson, C., Sanni, A., Wyrley-Birch, H., Vijayanand, D., Reddy, M., Rix, D., Manas, D., and Talbot, D.
- Subjects
- *
KIDNEY diseases , *URINARY organs , *ISCHEMIA , *GENITOURINARY organs - Abstract
Abstract: Kidneys transplanted from non-heart-beating donors (NHBDs) have been exposed to varying degrees of ischemic damage after death. Category III donors have invariably been managed, treated, and investigated in a hospital setting prior to arrest and death. Some therefore exhibit evidence of renal dysfunction and even acute renal failure (ARF) before death. Many surgeons would regard a NHBD with pre-arrest evidence of ARF as too marginal for renal transplantation. This retrospective study examines five Maastricht category III NHBD donors with evidence of pre-arrest ARF. We compare 3- and 12-month GFR outcome data from the nine resulting transplants with 40 category III NHBD transplants with normal pre-arrest renal function. The mean GFR at 3 months was 45.4 and 43.8 for the ARF and normal group, respectively. At 12 months the GFR was 42.2 and 44.7 in the ARF and normal groups, respectively. Thus evidence of ARF pre-arrest does not preclude successful category III NHBD renal transplantation. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
19. Agonal Period in Potential Non-Heart-Beating Donors
- Author
-
Sohrabi, S., Navarro, A., Asher, J., Wilson, C., Sanni, A., Wyrley-Birch, H., Anand, V., Reddy, M., Rix, D., Jacques, B., Manas, D., and Talbot, D.
- Subjects
- *
KIDNEY transplantation , *TRANSPLANTATION of organs, tissues, etc. , *URINARY organs , *ORGAN donation - Abstract
Abstract: The shortage of donor kidneys for renal transplantation is becoming more severe as the gap between the number of patients waiting for renal transplantation and the number of cadaveric organs available continues to widen. Therefore, many centres have started using non-heart-beating (NHB) donors. There was no clear plan for maximal duration of agonal period in Maastricht category NHB donors after withdrawal of treatment in Newcastle. This withdrawal has been audited in retrospect. Our current wait time is now a maximum of 5 hours; however, previously there have been some considerably longer periods. Concern has always been expressed about poor quality with protracted periods. Nonuse in this review of 58 kidneys can be expressed against time: 0 to 2 hours 13%, 2 to 5 hours 33%, and >5 hours 45%. Therefore, though the nonuse rate was significantly different between 0 to 2 hours and >5 hours (P < .05, chi-square), there were 16 transplants performed with kidneys >2 hours and 12 transplanted >5 hours. In conclusion, although good usable kidneys can still be used with protracted withdrawal, there are considerable logistical difficulties with our 5-hour cut-off, which means that one third of potential kidneys will not be utilized. [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
20. Primary and secondary phase separation in Cu–Zr–Al bulk metallic glass by control of quenching conditions.
- Author
-
Zhang, Y., Ren, S., Sohrabi, S., and Ma, J.
- Subjects
- *
PHASE separation , *METALLIC glasses , *TRANSMISSION electron microscopy , *COPPER , *TEMPERATURE control - Abstract
Here, we report primary and secondary nanoscale phase separation in Cu 46 Zr 46 Al 8 (at.%) bulk metallic glass (BMG) achieved by altering the casting temperature. The BMG rods were cast by using the melting currents of 160 A and 220 A which provide, respectively, higher and lower cooling rates. The transmission electron microscopy and energy-dispersive X-ray analysis revealed that the higher cooling rate conditions brings a primary phase separation of nanoscale Cu-rich amorphous regions which are evenly dispersed in the Cu-depleted amorphous matrix phase. However, lower cooling rates results in a bimodal microstructure comprising coarsened primary-separated nanograins and very fine secondary-separated nanograins throughout the amorphous matrix containing nanocrystals of smaller than 5 nm in size. This unique microstructure developed under lower cooling rates gives lower relaxation enthalpy, higher short-range ordering, and enhanced strain-hardening. Our study emphasizes the significant role of casting temperature on controlling the morphology of nanoscale phase separation in BMGs. • The effects of quenching conditions on the phase separation of Cu 46 Zr 46 Al 8 (at.%) BMG rods were studied. • Higher melt temperature (lower cooling rate) decreases relaxation and crystallization enthalpies. • Primary and secondary phase separation was observed at lower cooling rate conditions. • The underlying mechanism for the observed phase separations was delineated. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
21. Esophageal mass: the importance of clinical history in foreign body imaging.
- Author
-
Mangel PS, Sedgh J, Sohrabi S, and Setabutr D
- Published
- 2013
- Full Text
- View/download PDF
22. Donor Risk Factors for Renal Graft Thrombosis
- Author
-
Sanni, A., Wilson, C.H., Wyrley-Birch, H., Vijayanand, D., Navarro, A., Sohrabi, S., Jaques, B., Rix, D., Soomro, N., Manas, D., and Talbot, D.
- Subjects
- *
KIDNEY transplantation , *THROMBOSIS , *MULTIVARIATE analysis , *BLOOD coagulation - Abstract
Abstract: Graft thrombosis is one of the most devastating complications of transplantation. In obtaining consent prior to transplant, it is useful to share potential risk factors with the recipient. In order to do this, we explored the impact of different risk factors that could contribute to this complication. Using multivariate analysis we found that neither multiple vessels nor vascular injury had a bearing on the risk of graft thrombosis but atheroma did (P < .02). [Copyright &y& Elsevier]
- Published
- 2007
- Full Text
- View/download PDF
23. Non-Heart-Beating Kidney Transplantation: 6-Year Outcomes
- Author
-
Sanni, A.O., Wilson, C.H., Wyrley-Birch, H., Vijayanand, D., Navarro, A., Gok, M.A., Sohrabi, S., Jaques, B., Rix, D., Soomro, N., Manas, D., and Talbot, D.
- Subjects
- *
KIDNEY transplantation , *NON-heart-beating organ donation , *ABDOMEN , *URINARY organs - Abstract
Abstract: Non-heart-beating donor kidneys (NHBD) are being used to increase the donor pool due to the scarcity of cadaveric heart beating donors (HBD). We evaluated the long-term outcomes of renal transplantation using NHBD kidneys, comparing the first 100 NHBD kidneys transplanted at our facility to the next consecutive cadaveric HBD kidneys for graft survival, recipient survival, and quality of graft function. Recipient survival (P = .22) and graft survival (P = .19) at 6 years did not differ between recipients of NHBD (83%, 80%) and HBD (89%, 87%) kidneys. Quality of graft function using the mean glomular filtration rates were significantly lower in the NHBD group up to 3 months following discharge (41 ± 2 vs 47 ± 2, P = .007) but were then comparable up to 6 years following transplantation (43 ± 5 vs 46 ± 4, P = .55). [Copyright &y& Elsevier]
- Published
- 2006
- Full Text
- View/download PDF
24. Ultrasonic vibration enabled under-liquid forming of metallic glasses.
- Author
-
Li X, Li L, Sohrabi S, Fu J, Li Z, Chen Z, Sun R, Zhang Y, Huang J, Zhang H, Zhu J, Chen X, Song K, and Ma J
- Abstract
Competing Interests: Conflict of interest The authors declare that they have no conflict of interest.
- Published
- 2024
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.