A direct relationship existed between standing crops of zooplankton and distribution, growth, and feeding of young-of-the-year blueback herring, Alosa aestivalis, in the James River, Virginia. Zooplankton densities were highest upstream where food consumption and growth rates were correspondingly highest. A progressive downstream decrease and upstream increase in fish abundance occurred during the study. Condition (K) decreased after flooding from Hurricane Camille.Blueback herring fed primarily on copepods (Eurytemora a//inis, Cyclops vernalis, and Can. thocamptus robertcokeri), but cladocerans (Bosmina sp. and Diaphanosoma brachyurum) were also important. Selection (electivity) was strongest for adult copepods and weakest for copepod nauplii. Selection for copepodRes and Bosmina sp. was moderate to weak. Feeding occurred only during daylight. Predation on copepods and copepodires by blueback herring resulted in population dominance by the smaller Bosmina sp. Respiration experiments were carried out in the laboratory. The regression of oxygen consumption on temperature (routine metabolism) was expressed asLog 0 -----1.4451 q-0.0548 T, where O: oxygen consumption (rag O•/g wet weight per hr), and T= temperature (C). Energy transformations were computed from growth and respiration values converted to their calorific equivalents. Mean maintenance requirement (% of food assimilated) was 88.3%, compared to 11.7% for growth (% of food assimilated). In the present study energy transformations are computed for young-of-the-year blueback herring, Alosa aestivalis, in the James River, Virginia. Seasonal distribution, growth rates, and feeding habits are described. Application of the energetics approach to fish has been a relatively recent development. Winberg (1956) provided the theoretical basis for study of energy transformations in natural populations, but comparable studies have appeared only recently (). The anadromous blueback herring occurs from northern Florida to Nova Scotia (Bigelow and Schroeder 1953), and spawns from late March through May at water temperatures from 21 to 24 C (Bigelow and Welsh 1925). Transformation occurs at about 20 mm total length (Mansueti and Hardy 1967), and • Contribution Number 620 of the Virginia Institute of Marine Science. z Present Address: Escuela de Pesquerias y AlL mentos, Universidad Cat51ica de Valparaiso, Valparaiso, Chile. young-of-the-year remain in the estuaries until fall before migrating to sea. Juveniles remain in the Atlantic for three or four years before returning to spawn. Little has been published on young-of-theyear blueback herring. Massmann (1953) and Massmann, Ladd, and McCutcheon (1952) discussed relative abundance in Virginia estuaries. Brooks (1968) and Brooks and Dodson (1965) considered prey size selection. Chittenden (1972) described salinity tolerance experiments. STUDY AREAThe James River, the southernmost major tributary of the Chesapeake Bay, drains 26,000 km ø-and flows 560 km in a southeasterly direction from the Allegheny Mountains to the Chesapea...

This paper presents an overview of the NG Radio Access Network (NG-RAN) architecture and key protocols. NG-RAN is the new RAN defined in conjunction with 5G by 3GPP. The paper presents the overall architecture, migration path options, the 5G base station architecture and key protocol components.

Age, growth, length-weight relationship, sex ratio and food habits of the Argentine pejerrey, Basilichthys bonariensis (Cuv. and Val.), from Lake Peiiuelas, Valparaiso, ChileArgentine pejerreys were collected in Lake Pefiuelas during January 1973. Calculated growth rate was maximum during the 3rd year of life. The length-weight relationship was:log W=-5.69395+3.25248 log L, where W=weight (g), and L=total length (rnm). Agegroup I was sexually mature. The sex ratio was 85 males (54%) to 73 females (46%). Young-of-the-year pejerreys fed primarily on copepods, but cladocerans [Bosmina sp. (Baird), Diaphanosonza brachyurum (Likven), Simocephalus serrulatus (Koch)], ostracods, and dipterans were also represented. Feeding occurred during daylight. w x 105 K = -299 L3

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American smelt were collected monthly for one year from a southern Michigan lake. The length frequency distribution indicated one race of smelt was present. Greatest growth in length occurred during the second year. The general length‐weight equation was: Log W = −5.0925 + 2.9539 Log L, where W = weight in grams, and L = total length in millimeters. The correlation coefficient (r) was 0.9954. Sex ratios indicated a differential mortality between the sexes; females predominated in age‐groups I to IV, and their proportion increased with age. Feeding activity and diets varied seasonally. Smelt were selective plankton feeders preying primarily on dipteran larvae (Chaoborus, Tendipedidae) and small crustaceans (Cladocera, Copepoda, Ostracoda). Young‐of‐the‐year smelt were the only fish consumed.