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A study of changes in sea surface temperature (SST) on the southwestern shelf of Crimea in 2000–2020 has been conducted. The equations of trends in the change in SST are found. It is shown that, according to the nature of changes in the average annual sea temperature, three periods can be distinguished: 2000–2007, 2008–2013, and 2014–2020. The influence of changes in the average annual SST on the development of pelagic fish of the cold-water complex (using the example of the Black Sea sprat) is considered. Changes in the main parameters of populations and their relationship with the change in the average annual SST are found. It is found that the observed increase in sea temperature negatively affected the development of the sprat population; the average age of the population has decreased by 1.3 times. In general, the population has been rejuvenated, and the average size and weight of individuals has decreased. [ABSTRACT FROM AUTHOR]

The influence of the average annual sea surface temperature (SST) on the development of the horse mackerel Trachurus mediterraneus on the southwestern Crimean shelf has been shown. The changes in the main indicators of the population and their relationship with the change in the average annual SST (0.055°С/year) in 2000–2020 have been identified. Against the background of the observed increase in SST in recent years, the state of the horse mackerel population has improved: there has been an increase in the average age and, accordingly, the proportion of larger well-fed individuals, and, in general, the average size and weight of fish. It has been shown that according to the nature of the change in the average annual SST, three periods can be distinguished: 2000−2007, 2008−2013, and 2014−2020. [ABSTRACT FROM AUTHOR]

In experimental culture conditions in tanks, the effect of weight ( W: 11-452 g) and temperature ( T: 14-29°C) on the growth rate (SGR, % bw day) and maximum daily food intake (SFR, % bw day) in sharpsnout sea bream ( Diplodus puntazzo) was studied. The possible combined effect of both independent variables ( W and T) was also analyzed by multiple regression analysis, fitting the data to the equation Ln Y = Ln a + b Ln W + cT + dT + eT Ln W. Both SGR and SFR, and therefore feed efficiency (FE = SGR/SFR), were significantly influenced by the interaction between temperature and weight and may be expressed by means of the following equations: Ln SGR = −6.1705 + 0.5809 T − 0.0087 T − 0.0249 T Ln W ( $$ R_{\text{adj}}^{2} $$ = 0.949; ANOVA P < 0.0001); Ln SFR = −4.8257 + 0.4425 T − 0.0063 T − 0.0163 T Ln W ( $$ R_{\text{adj}}^{2} $$ = 0.964; ANOVA P < 0.0001).The results suggest that the optimum temperature for SGR and FE ( T and T), and the temperature at which the maximum SFR ( T) is reached, decreases with body weight, in accordance with the equations: T = 33.297 − 1.435 Ln W; T = 29.332 − 1.890 Ln W; and T = 34.941 − 1.304 Ln W, respectively. In this way, T is 28.4, 26.7, and 24.7°C; T is 30.5, 28.9, and 27.1°C and T is 22.9, 20.6, and 18°C for 30, 100 and 400 g body weight, respectively. [ABSTRACT FROM AUTHOR]

The yielding properties of the cell wall, irreversible wall extensibility (m) and yield threshold (Y), are determined for stage I sporangiophores of Phycomyces blakesleeanus from in-vivo creep experiments, and compared to the values of m and Y previously determined for stage IVb sporangiophores using the same pressureprobe method (Ortega et al., 1989, Biophys. J. 56, 465). In either stage the sporangiophore enlarges (grows) predominately in length, in a specific region termed the 'growing zone', but the growth rates of stage I (5-20 urn · min) are smaller than those of stage IVb (30-70 μm · min). The results demonstrate that this difference in growth rate is the consequence of a smaller magnitude of m for stage I sporangiophores; the obtained values of P (turgor pressure), Y, and P-Y (effective turgor for irreversible wall extension) for stage I sporangiophores are slightly larger than those of stage IVb sporangiophores. Also, it is shown that the magnitude of m for the stage I sporangiophore is regulated by altering the length of the growing zone, L. A relationship between m and L is obtained which can account for the difference between values of m determined for stage I and stage IVb sporangiophores. Finally, it is shown that similar changes in the magnitude of m and ϕ (which have been used interchangeably in the literature as a measure of irreversible wall extensibility) may not always represent the same changes in the cell-wall properties. [ABSTRACT FROM AUTHOR]