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In the current study, we report the thermal tolerance, standard metabolic rate (SMR) and preferred temperature of juvenile European sea bass (Dicentrarchus labrax) (1.2 ± 0.4 g) acclimated at 15, 20, 25 and 30 °C for 30 days. Dynamic and static thermal tolerance zones of juvenile European sea bass are 861 °C2 and 613 °C2, respectively. The European sea bass is a fish species with low thermal resistance, with a resistance zone area of 162.5 °C2. The SMR of the fish species at the above acclimation temperatures are 184, 255, 382 and 459 mg O2 h−1 kg−1, respectively and are significantly different (P

The Acartia tonsa, a calanoid copepod species, has high survival and thermal acclimation capacity in aquatic environments characterized by temperature variations. Dynamic and static thermal polygon areas of this species are 495 °C2 and 267 °C2 for nauplii stage, while adult stage has 747 °C2 and 411 °C2 dynamic and static thermal polygon area, respectively. In addition, Acartia tonsa is a copepod species which is more resistant to both high and low lethal temperatures, with its resistance zone of 105 °C2 and 131 °C2 for nauplii and adults, respectively. Acartia tonsa nauplii acclimated to 18 °C, 23 °C and 28 °C have lover and upper thermal limit (CTMin-CTMax) of 6.82–26.15 °C, 8.65–29.49 °C, and 11.70–34.10 °C, respectively. This species in the adult stage has a CTMin-CTMax of 4.47–30.30 °C, 6.35–33.94 °C, and 9.92–35.90 °C at acclimation temperatures mentioned above. Its broad dynamic and static thermal tolerance polygon areas and, accordingly, its significant thermal limits allow Acartia tonsa to survive at warm or cold extremes in their natural environment.

Fixed point theorems for weak- \(\left( \psi ,\alpha ,\beta \right) \)- contractive mappings have been introduced and investigated for different kinds of metric spaces. The paper first discusses a particular condition and then a weak contractive condition generalizing existing such conditions is defined. Our primary aim is to investigate the Banach, Kannan and Chatterjea’s fixed point theorems in complete metric spaces satisfying the new weak contractive condition and their applications. In the sequel, several auxiliary results are investigated and also incorporated sufficient number of examples in suitable places to justify certain claims.

In this study, a numerical and experimental study was carried out to determine the effects of variables such as curvature and foam properties on the natural frequencies of the sandwich panels. Sandwich panels consist of laminated E/glass epoxy face sheets with [0 degrees/90 degrees/-45 degrees/+45 degrees] stacking sequences and PVC foam cores with AIREX C70.55, C70.90, C70.200 and C70.250. A group of sandwich panels with radii of curvature ranging from 90 to 200 mm were analysed by ANSYS software. Vibration characteristics were obtained for clamped square sandwich panels. The results indicate that the natural frequencies increase with the increasing curvature and foam density. However, the increment in the natural frequency due to an increase in the magnitude of curvature decreases with increasing foam density. The highest increase in natural frequency due to increasing foam properties is seen in the flat panels. Also, it is found that in values beyond a specific curvature; increasing of the foam properties causes reduction in the natural frequencies. (C) 2017 Elsevier Ltd. All rights reserved.

In this paper, a generalized fixed point theorem and its results are established in the concept of multiplicative distance which was introduced by Agamirza et.al [3] to improve the non-Newtonian calculus. Our results include some existing results in the concept of multiplicative metric space.

Sea bream, Sparus aurata, is one of the most important fish species that is commonly cultured in the Mediterranean and the eastern coasts of the Atlantic Ocean. The life cycle of sea bream in its natural habitat passes through hyposaline and hypersaline lagoons. It is important to determine the tolerance of the fish to nitrogenous compounds for aquaculture at maximum stocking densities. In the present study, a series of acute experiments were performed to evaluate the effect of salinity on ammonia and nitrite toxicity to sea bream. The fish were exposed to different ammonia and nitrite concentrations according to the static renewal methodology at three different salinities (10, 20, and 30 ppt) and at a temperature of 20 C and a pH of 8.2. The toxic effect of total ammonia nitrogen (TAN) and nitrite nitrogen (NO2-N) decreased with increasing salinity levels (P

The purpose of this paper is to present some existence results for coupled fixed point of a (φ,ψ) —contractive condition for mixed monotone operators in metric spaces endowed with a directed graph. Our results generalize the results obtained by Jain et al. in (International Journal of Analysis, Volume 2014, Article ID 586096, 9 pages). Moreover, we have an application to some integral system to support the results.

The present study reports the temperature tolerance, estimated using dynamic and static methodologies, and preferred temperature range, based on oxygen consumption rate (OCR), of juvenile meagre (Argyrosomus regius) (Asso, 1801) (3.4±0.9g) after 30 days of acclimation at 18, 22, 26 and 30°C. Meagre has dynamic and static thermal tolerance zones of 551°C2 and 460°C2, respectively and is a low resistance fish species, with a resistance zone area of 87°C2. The OCR of juvenile meagre at the above acclimation temperatures was 370, 410, 618 and 642mgh-1kg-1, respectively, and is significantly different (P

n this paper, we derive a new fixed point results in partially ordered b-metric-like spaces. Our results generalize and extend several well-known comparable results in the literature. Further, two examples are also given to show that our results are influential. (C) 2016 All rights reserved.

In this paper, our purpose is to show that Kannan Type and Chatterjea type contractive mappings have unique fixed point in b-metric spaces. Also, we see surprisingly a way that contrary to the known (usual) metric spaces, any contraction mapping is not need to be a weak conraction mapping in b-metric spaces.

Triploidy in fertilized eggs of Penaeus semisulcatus was induced by temperature and chemical shocks. The eggs, which were obtained from the shrimp broodstock maintained at 29C, were exposed to cold temperature (8, 10, 12, and 14 C) and 6-dimetiloaminopurine (6-DMAP) concentrations (100, 150, 200, and 250 μM) for different durations (4, 6, and 8min) 9min after spawning was detected. While the highest triploidy rate of 49.7±4.5% was obtained with a 200μM 6-DMAP concentration for a duration of 8min, the best mean triploidy rate of 45.5±2.8% for cold shock was obtained at a temperature of 10 C for a duration of 8min. Temperature and 6-DMAP concentration did not have significant effect on triploidy rate (P>0.05) but shock duration had significant effect on triploidy rate for individual cold temperature shock or 6-DMAP chemical shock (P, Scientific and Technological Research Council of Turkey (109O431); Muğla Sıtkı Koçman University (2011-2)

Temperature variation affects the growth, maturation and distribution of fish species due to increasing constraints on physiological functions therefore, the aim of the present study is to evaluate effect of temperature on thermal tolerance and standard metabolic rate (SMR) of gilthead seabream (Sparus aurata). For this purpose, tolerable temperature ranges of juvenile gilthead seabream acclimated at 15, 20, 25, and 30 °C for 30 days were estimated using dynamic and static thermal methodologies. The SMRs of the fish were also determined based on oxygen consumption rate (OCR). The dynamic and static thermal tolerance zones of gilthead seabream were calculated as 737 °C2 and 500 °C2, respectively, with a resistance zone area of 155.5 °C2. The SMR of the fish at the above acclimation temperatures (AT) was determined as 138, 257, 510, and 797 mg O2 h-1 kg-1, respectively and were significantly different (P

In this paper, we study the notions of accretive operators, contraction mappings, non-expansive mappings using the idea of n (>1)-normed structures for some relevant results. Further, we define \(\left( \lambda ,q\right) \)-transform by utilizing the definition of the generating function of q-Genocchi polynomials with weight zero to construct interesting properties related to q-Genocchi polynomials with weight zero and Frobenius–Euler polynomials. Furthermore, we describe p-adic q-\( \lambda \)-transform of higher order and construct a link between q-Genocchi polynomials of higher order with weight zero and higher order Frobenius–Euler polynomials using this transform. Our applications in this paper provide a link between analytic numbers theory and n-normed spaces.

Eslamian and Abkar (8) introduced fixed point of the weak- (ψ, α, β) contractive mappings in complete metric space (also see (9)). In this paper we established a generalized concept of the weak-(ψ, α, β) contractive condition depended on another mapping. Thus, we obtained a new generalization of Banach fixed point t heorem, Kannan fixed point theorem and Chatterjea fixed point theorem.

Palaemon serratus juveniles (0.18 ± 0.06 g) were exposed to different concentrations of ammonia in a series of acute toxicity tests by the static renewal method at four salinity levels (10, 20, 30, and 40 ppt) at 29 C and at a pH of 8.0. Oxygen consumption rate (OCR) was also measured. The mortality rate increased with increasing concentrations of ammonia and longer exposure times. High salinity levels clearly increased the tolerance of shrimp to total ammonia nitrogen (TAN) and unionized ammonia (NH3) (P < 0.05). The safe level for P. serratus was estimated to be 2.1, 3.5, 3.8, and 8.5 mg/L for TAN and 0.13, 0.21, 0.24, and 0.53 mg/L for NH3 at 10, 20, 30, and 40 ppt salinity levels, respectively. OCR of P. serratus increased with increasing salinity and TAN concentrations. This study clearly indicated that there is a relationship between an increment in salinity or TAN and the OCR of P. serratus juveniles (P < 0.05).

In this paper, we introduce $\alpha-\psi$ type contractive mapping in rectangular metric space satisfying certain admissibility conditions and prove a fixed point result for such mapping in complete and Hausdorff rectangular metric space. Some examples are given to justify our result. Also we have shown that the existence of solution of a nonlinear fractional differential equation can be guaranteed, as an application of our result.

In this paper, we discuss the concept of partially ordered rectangular metric spaces using the notation .X; ; d/. Also, we give a generalized contractive condition in the context of partially ordered rectangular metric space for all comparable p

The fixed point theorems of contraction mappings in n−normed spaces was studied. ( M. Kir and H. Kiziltunc, On Fixed Point Theorems For Contraction Mappings in n-Normed Spaces, (AMISL) ). By the same motivation, we will derive some fixed point theorems for nonself contraction mappings in n-Banach spaces which we stated in the present paper.

In this paper, our purpose is to give a new generalization of Kannan's type and Chatterjea's type fixed point theorems in metric spaces. We have two main ideas. Our first idea is applyi ng the logic of Choudhury (5) to the Kannan type contraction mappings, the second is applying the logic of Dutta and Choudhury (6) to the Kannan type contraction mappings and Chatterjea type contraction mappings.

In this paper, we introduce j contraction mappings in 2-normed spaces and we show that the mappings have a unique fixed point in 2-Banach spaces. Also, we introduced a new fixed point theorem for nonselfmappings applying the definition of retraction to 2-Banach spaces.

Ammonia tolerance of European sea bass (Dicentrarchus labrax) juveniles (1.1 ± 0.3 g) was investigated by a series of acute toxicity experiments at different salinity levels (10, 20 and 30 ppt) at pH 8.0 and temperature 22 °C. Oxygen consumption rates were also measured to determine the Standard Metabolism (SM) of the fish. The tolerance of the fish to total ammonia nitrogen (TAN) and unionized ammonia (NH3) increased significantly with increasing salinity levels. The safe level for European sea bass was estimated to be 0.4, 1.0 and 1.6 mg L−1 for TAN and 0.02, 0.04 and 0.07 mg L−1 for NH3 at 10, 20 and 30 ppt salinity levels, respectively. At any, each level, the SM of the fish increased with increasing TAN concentration (P

Triploidy in fertilized eggs of Melicertus kerathurus was induced by cold (8, 10, 12°C) and heat (34, 36, 38°C) shock for different duration times (2, 4 and 8 min) after 10 min of post spawning. The best individual treatment produced 64.5% triploid nauplii in cold shock application at a temperature of 10°C for a duration of 8 min. Temperature did not have significant effect (P > 0.05) on triploid rate but duration time had a significant effect (P < 0.05) for individual cold or heat shock. This study demonstrates that because of a wide variety of effective parameters, it is essential to optimize shock conditions for each species strain at each location. © 2016 John Wiley & Sons Ltd., Muğla Sıtkı Kocman University (2008-11/2009-26)

Some new coupled coincidence and coupled common fixed point theorems for $\varphi$-$\psi$-contraction mappings are established. We have also an application to some integral system to support the results.

Critical thermal minima (CTmin) and lower incipient lethal temperature (LILT) were determined for Penaeus semisulcatus juveniles at four different acclimation temperatures (14, 20, 26, and 32 C). The effect of cooling rate on the CTmin was also investigated. The CTmin of shrimps at these respective acclimation temperatures were 7.1, 8.9, 10.5, 12.6 C and 6.6, 8.0, 9.7, 11.4 C and 6.1, 7.2, 8.3, 9.9 C for the cooling rates of 0.25, 0.5, and 1.0 C/h, respectively. The LILT value of P.semisulcatus were 5.23, 6.14, 7.36, 8.57 C at 14, 20, 26, and 32 C, respectively. The results indicated that both the cooling rate and the acclimation temperature significantly affected the CTmin (P < 0.05). Acclimation temperature had also significant effects on the LILT of P. semisulcatus (P < 0.05). In acclimation temperatures between 14 and 32 C, the acclimation response ratio values were 0.30, 0.26, and 0.21 at the cooling rates of 0.25, 0.5, and 1 C/h, respectively. The cold tolerance zone in which P. semisulcatus can survive for short period in this study ranged from 6.1 to 12.6 C. © Copyright by the World Aquaculture Society 2008.

In this paper, the concept of weakly TF -contractive conditions are considered for the Banach, Kannan and Chatterjea fixed point theorems. It is shown that these mappings have a unique fixed point in a complete metric space.

The effects of increased dietary sodium chloride supplement on growth, feed efficiency (FE), feed dispensed rate and fillet composition and morphological indices of European sea bass (initial weight of 4.9 g) were investigated in freshwater using five different levels of supplemental salt (0 (control diet, with no salt supplemented), 1%. 3%, 5% and 9% of diet). Over the experimental period of 50 days, the final weight of dietary salt (DS) groups was found to be approximately 19% higher than the control group. The final weight, specific growth rate and FE were greatest at the moderate level (1-5%) of salt supplementation. Optimum level of DS inclusion, was calculated as 3%. Feed efficiency was significantly enhanced with increasing salt level up to 5%. A negative relationship between daily feed intake and FE (r2 = 0.66) was observed. The average muscle ratio (MR) in groups fed 1-5% supplemented salt was around 51.4% whereas fish receiving control and 9% salty diets had 5.3% lower MR (48.7%) (P < 0.05). However, no significant effects of salt inclusion were found on viscera or hepatosomatic indices. Muscle ash and dry matter content slightly rose with increasing DS in the diet, but with no statistical difference (P > 0.05). Similarly, no significant changes were observed in either muscle protein or lipid content among the groups (P > 0.05). © 2005 Blackwell Publishing Ltd.

The fundamental aim of this paper is to introduce and investigate a new property of quasi 2-normed space based on a question given by C. Park (2006) [2] for the completion quasi 2-normed space. Finally, we also find an answer for a question Park's., Comment: 7 pages

Stocking densities of cultured penaeid shrimp have been intensified because of the limited availability of land for pond construction. In an intensive culture system, ammonia is the most common toxicant resulting from nitrogen excretion by cultured animals and mineralization of unconsumed feed and feces (Lin and Chen 2003). In decapod crustaceans, nitrogen is excreted mainly as ammonia (60–70% of total ammonia) (Lee and Chen 2003). Concentrations of total ammonia-nitrogen (TAN) increase directly with culture period and might reach as high as 46 mg TAN/L in intensive grow-out ponds (Chen and Lin 1992). Accumulation of ammonia-nitrogen in pond water may deteriorate water quality, reduce growth, increase oxygen consumption, alter concentrations of hemolymph protein and free amino acid levels, and even cause high mortality (Chen and Lin 1992; Chen et al. 1994). TAN is composed of NH3-N (unionized ammonia) andNH4+ (ionized ammonia) (Losordo et al. 1992; Masser et al. 1992). It is the unionized form that is most toxic to aquatic organisms as it can readily diffuse through cell membranes and is highly soluble in lipids (Chin and Chen 1987; Frias-Espericueta et al. 1999). There is an equilibrium between NH4+ and NH3-N in the water. This equilibrium is affected by pH, temperature, and salinity. The higher the pH and temperature, the higher the proportion of NH3-N, while an increase in salinity will lead to lower proportions of the unionized form, hence the toxicity of the TAN to aquatic animals (Losordo et al. 1992;Masser et al. 1992; Sampaio et al. 2002). A number of studies have been conducted on the lethal effects of ammonia at various life stages of penaeid shrimps, such as Penaeus chinensis (Chen and Lin 1992), P. monodon (Chen and Lei 1990), P. paulensis (Ostrensky and Wasielesky 1995), P. penicillatus (Chen and Lin 1991), P. semisulcatus (Wajsbrot et al. 1990), and Metapenaeus ensis (Nan and Chen 1991). However, little information is available on the lethal effect of ammonia at different salinity levels for penaeid shrimps. Chen and Lin (1992) and Lin and Chen (2003) studied ammonia toxicity in P. chinensis and Litopenaeus vannamei at three different salinity levels, but no results have been reported for other penaeid species. Green tiger shrimp (P. semisulcatus) is an Indo-Pacific species, distributed along the coast of the Eastern Mediterranean, and is one of the most important commercial species in this part of the world. This species is less tolerant to low salinity levels (Soyel and Kumlu 2003), and knowledge of the effects of ammonia toxicity at various salinity regimes that may be confronted during the culture and overwintering periods in the subtropical areas is of importance for the farmers. This paper provides information on acute toxicity of ammonia to juveniles of this shrimp species at six different salinity levels (15, 20, 25, 30, 35, and 40 ppt).

Over-wintering of Penaeus semisulcatus (20.61 g) at three different temperatures (14. 18 and 22°C) was carried out in a greenhouse in three different closed recirculating systems. Temperature significantly influenced specific growth rate (SGR) and moulting interval (MI) (P < 0.05). The SGR was 15-fold higher and the MI was 2.7-fold shorter at 22°C in comparison with 14°C. The relationship between SGR and temperature (T) was: Y = - 0.053+0.070T (R2 = 0.97). Shrimps over-wintered at 14°C consumed almost three times less food (0.43% body weight) than those at 22°C (1.28%) (P < 0.05). A positive relationship (FR = 0.426T-0.020. R2 = 0.99) was observed between feeding rate (FR) and temperature. The survival rate achieved at 14. 18 and 22°C over the experimental period of 70 days was 87%, 67% and 73% respectively. Our data indicate that it is possible to over-winter this shrimp species in the sub-tropical regions by maintaining water temperature at around 14°C and 39 ppt salinity, in which little energy expenditure is needed, and the shrimp can survive and consume minimum amount of feed.

WOS: 000225182400014 PubMed ID: 15528173 The effects of neuropeptide Y (NPY) administered intramuscularly or orally on postlarvae (PLs) of two penaeid species were investigated in this study. In experiment 1, food intake (FI) of Marsupenaeus japonicus PLs (0.96 g), injected with NPY at 0.6 mug per g BW, was investigated within 48 h posttreatment. In experiment 2, oral administration of NPY (at doses of 0, 0.125, 0.25, 0.5 mug g(-1) food) on feed intake and growth performance of Penaeus semisulcatus PLs (0.27 g) was examined for 6 weeks. In experiment 1, NPY injection significantly increased average daily FI of M japonicus PLs within the first 24 h compared to the control (P0.05). The increase in FI was 33% during the first 24 h and 17% during the next 24 h. In experiment 2, significant (P

Penaeus semisulcatus juveniles (1.6±0.2 g) were exposed to different concentrations of ammonia-N in a series of acute toxicity tests by the semi-static method at four different water temperatures (14, 18, 22 and 26°C) at pH of 8.2 and 39 ppt salinity. The mortality rate increased with increasing concentrations of ammonia and exposure time. Low temperatures clearly increased tolerance of the shrimps to total ammonia-nitrogen (TAN) and un-ionised ammonia (NH3-N). The 24-, 48-, 72- and 96-h LC 50 values of TAN were 92.22, 76.56, 64.07 and 55.84 mg l-1 at 14°C; 57.00, 46.07, 41.85 and 36.01 mg l-1 at 18°C; 41.10, 33.42, 30.61 and 26.72 mg l-1 at 22°C; and 25.89, 15.44, 13.44 and 11.44 mg l-1 at 26°C, respectively. The 24-, 48-, 72- and 96-h LC50 values of NH3-N were 3.18, 2.64, 2.22 and 1.92 mg l-1 at 14°C; 2.94, 2.37, 2.15 and 1.85 mg l-1 at 18°C; 2.77, 2.25, 2.06 and 1.80 mg l-1 at 22°C; and 2.26, 1.35, 1.17 and 1.00 mg l-1 at 26°C, respectively. The safe level for rearing P. semisulcatus was estimated to be 5.6, 3.6, 2.7 and 1.1 mg l -1 for TAN and 0.19, 0.19, 0.18 and 0.10 mg l-1 for NH3-N at 14, 18, 22 and 26°C water temperatures, respectively. The safe level was fivefold higher for TAN and twofold higher for NH 3-N at 14°C in comparison to 26°C. © 2004 Elsevier B.V. All rights reserved. FBE.2002 Applied Scientific Research Fund This study was financed by the Scientific Research Fund of the University of Çukurova, Turkey (FBE.2002.D.166).