Morphology and Developmental Stages of Piona linguaplax n. sp. (Hydracarina:Pionidae) a Water-mite from North Carolina

1953 ◽  
Vol 50 (2) ◽  
pp. 426 ◽  
Author(s):  
Robert M. Crowell
2021 ◽  
Vol 104 (3) ◽  
Author(s):  
Christine A. Nalepa ◽  
Kelly L. F. Oten ◽  
Matthew A. Bertone

1968 ◽  
Vol 100 (2) ◽  
pp. 178-180
Author(s):  
Robert M. Crowell

AbstractOviposition and hatching of Albia caerulea Marshall, 1927, are reported from laboratory observations of adults collected in Lake Opinicon, Leeds County, Ont., and of eggs deposited by them. A description is presented of newly hatched, unengorged larvae. Figures of the larva and eggs are included. Additional locality records of this species of water mite are reported.


Itinerario ◽  
2000 ◽  
Vol 24 (2) ◽  
pp. 146-169 ◽  
Author(s):  
Michael Leroy Oberg

In August of 1587 Manteo, an Indian from Croatoan Island, joined a group of English settlers in an attack on the native village of Dasemunkepeuc, located on the coast of present-day North Carolina. These colonists, amongst whom Manteo lived, had landed on Roanoke Island less than a month before, dumped there by a pilot more interested in hunting Spanish prize ships than in carrying colonists to their intended place of settlement along the Chesapeake Bay. The colonists had hoped to re-establish peaceful relations with area natives, and for that reason they relied upon Manteo to act as an interpreter, broker, and intercultural diplomat. The legacy of Anglo-Indian bitterness remaining from Ralph Lane's military settlement, however, which had hastily abandoned the island one year before, was too great for Manteo to overcome. The settlers found themselves that summer in the midst of hostile Indians.


Author(s):  
J. P. Revel

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.


Author(s):  
J. R. Adams ◽  
G. J Tompkins ◽  
A. M. Heimpel ◽  
E. Dougherty

As part of a continual search for potential pathogens of insects for use in biological control or on an integrated pest management program, two bacilliform virus-like particles (VLP) of similar morphology have been found in the Mexican bean beetle Epilachna varivestis Mulsant and the house cricket, Acheta domesticus (L. ).Tissues of diseased larvae and adults of E. varivestis and all developmental stages of A. domesticus were fixed according to procedures previously described. While the bean beetles displayed no external symptoms, the diseased crickets displayed a twitching and shaking of the metathoracic legs and a lowered rate of activity.Examinations of larvae and adult Mexican bean beetles collected in the field in 1976 and 1977 in Maryland and field collected specimens brought into the lab in the fall and reared through several generations revealed that specimens from each collection contained vesicles in the cytoplasm of the midgut filled with hundreds of these VLP's which were enveloped and measured approximately 16-25 nm x 55-110 nm, the shorter VLP's generally having the greater width (Fig. 1).


Author(s):  
Regina Birchem

Spheroids of the green colonial alga Volvox consist of biflagellate Chlamydomonad-like cells embedded in a transparent sheath. The sheath, important as a substance through which metabolic materials, light, and the sexual inducer must pass to and from the cells, has been shown to have an ordered structure (1,2). It is composed of both protein and carbohydrate (3); studies of V. rousseletii indicate an outside layer of sulfated polysaccharides (4).Ultrastructural studies of the sheath material in developmental stages of V. carteri f. weismannia were undertaken employing variations in the standard fixation procedure, ruthenium red, diaminobenzidine, and high voltage electron microscopy. Sheath formation begins after the completion of cell division and inversion of the daughter spheroids. Golgi, rough ER, and plasma membrane are actively involved in phases of sheath synthesis (Fig. 1). Six layers of ultrastructurally differentiated sheath material have been identified.


Author(s):  
Y. R. Chen ◽  
Y. F. Huang ◽  
W. S. Chen

Acid phosphatases are widely distributed in different tisssues of various plants. Studies on subcellular localization of acid phosphatases show they might be present in cell wall, plasma lemma, mitochondria, plastid, vacuole and nucleus. However, their localization in rice cell varies with developmental stages of cells and plant tissues. In present study, acid phosphatases occurring in root cap are examined.Sliced root tips of ten-day-old rice(Oryza sativa) seedlings were fixed in 0.1M cacodylate buffer containing 2.5% glutaraldehyde for 2h, washed overnight in same buffer solution, incubated in Gomori's solution at 37° C for 90min, post-fixed in OsO4, dehydrated in ethanol series and finally embeded in Spurr's resin. Sections were doubly stained with uranyl acetate and lead citrate, and observed under Hitachi H-600 at 75 KV.


2019 ◽  
Vol 4 (4) ◽  
pp. 633-640 ◽  
Author(s):  
Canice E. Crerand ◽  
Ari N. Rabkin

Purpose This article reviews the psychosocial risks associated with 22q11.2 deletion syndrome, a relatively common genetic condition associated with a range of physical and psychiatric problems. Risks associated with developmental stages from infancy through adolescence and early adulthood are described, including developmental, learning, and intellectual disabilities as well as psychiatric disorders including anxiety, mood, and psychotic disorders. Other risks related to coping with health problems and related treatments are also detailed for both affected individuals and their families. Conclusion The article ends with strategies for addressing psychosocial risks including provision of condition-specific education, enhancement of social support, routine assessment of cognitive abilities, regular mental health screening, and referrals for empirically supported psychiatric and psychological treatments.


Sign in / Sign up

Export Citation Format

Share Document