Femtosecond Dynamics of Excited-State Evolution in

Time-resolved absorption spectroscopy on the femtosecond time scale has been used to monitor the earliest events associated with excited-state relaxation in tris-(2,2'-bipyridine)ruthenium(II). The data reveal dynamics associated with the temporal evolution of the Franck-Condon state to the lowest energy excited state of this molecule. The process is essentially complete in approximately 300 femtoseconds after the initial excitation. This result is discussed with regard to reformulating long-held notions about excited-state relaxation, as well as its implication for the importance of non-equilibrium excited-state processes in understanding and designing molecular-based electron transfer, artificial photosynthetic, and photovoltaic assemblies in which compounds of this class are currently playing a key role.     

Contingency and determinism in replicated adaptive radiations of island lizards

The vagaries of history lead to the prediction that repeated instances of evolutionary diversification will lead to disparate outcomes even if starting conditions are similar. We tested this proposition by examining the evolutionary radiation of Anolis lizards on the four islands of the Greater Antilles. Morphometric analyses indicate that the same set of habitat specialists, termed ecomorphs, occurs on all four islands. Although these similar assemblages could result from a single evolutionary origin of each ecomorph, followed by dispersal or vicariance, phylogenetic analysis indicates that the ecomorphs originated independently on each island. Thus, adaptive radiation in similar environments can overcome historical contingencies to produce strikingly similar evolutionary outcomes.     

Simulated increase of hurricane intensities in a CO2-warmed climate

Hurricanes can inflict catastrophic property damage and loss of human life. Thus, it is important to determine how the character of these powerful storms could change in response to greenhouse gas-induced global warming. The impact of climate warming on hurricane intensities was investigated with a regional, high-resolution, hurricane prediction model. In a case study, 51 western Pacific storm cases under present-day climate conditions were compared with 51 storm cases under high-CO2 conditions. More idealized experiments were also performed. The large-scale initial conditions were derived from a global climate model. For a sea surface temperature warming of about 2.2 degrees C, the simulations yielded hurricanes that were more intense by 3 to 7 meters per second (5 to 12 percent) for wind speed and 7 to 20 millibars for central surface pressure.     

Comparison of histological lesions and immunohistochemical staining of proteinase-resistant prion protein in a naturally occurring spongiform encephalopathy of free-ranging mule deer (Odocoileus hemionus) with those of chronic wasting disease of captive mule deer

In this investigation, the nature and distribution of histologic lesions and immunohistochemical staining (IHC) of a proteinase-resistant prion protein were compared in free-ranging mule deer (Odocoileus hemionus) dying of a naturally occurring spongiform encephalopathy (SE) and captive mule deer dying of chronic wasting disease (CWD). Sixteen free-ranging deer with SE, 12 free-ranging deer without SE, and 10 captive deer with CWD were examined at necropsy. Tissue sections were stained with hematoxylin and eosin, and duplicate sections were stained with a monoclonal antibody (F89/160.1.5). Histological lesions in the free-ranging deer with SE and captive deer with CWD were found throughout the brain and spinal cord but were especially prominent in the myelencephalon, diencephalon, and rhinencephalon. The lesions were characterized by spongiform degeneration of gray matter neuropil, intracytoplasmic vacuolation and degeneration of neurons, and astrocytosis. IHC was found throughout the brain and retina of deer with SE and CWD. Positive IHC was found in lymphoid tissue of deer with SE and CWD. Histologic lesions and IHC were not found in multiple sections of integument, digestive, respiratory, cardiovascular, endocrine, musculoskeletal, and urogenital systems of deer with SE or CWD. Comparison of histologic lesions and IHC in tissues of free-ranging deer with those of captive deer provides strong evidence that these two diseases are indistinguishable morphologically.     

Distribution of protease-resistant prion protein and spongiform encephalopathy in free-ranging mule deer (Odocoileus hemionus) with chronic wasting disease

Serial sections of brain and palatine tonsil were examined by immunohistochemical staining (IHC) using monoclonal antibody F89/160.1.5 for detecting protease-resistant prion protein (PrP(res)) in 35 hunter-killed mule deer (Odocoileus hemionus) with chronic wasting disease. Serial sections of brain were stained with hematoxylin and eosin and examined for spongiform encephalopathy (SE). Clinical signs of disease were not observed in any of these deer. On the basis of the location and abundance of IHC and the location and severity of SE, deer were placed into four categories. Category 1 (n = 8) was characterized by IHC in the palatine tonsil with no evidence of IHC or SE in the brain. Category 2 (n = 13) was characterized by IHC in the palatine tonsil and IHC with or without SE in the dorsal motor nucleus of the vagus nerve (DMNV). Category 3 (n = 2) was characterized by IHC in the palatine tonsil, IHC with SE in the myelencephalon, and IHC without SE in the hypothalamus. Category 4 (n = 12) was characterized by IHC in the palatine tonsil and IHC with SE throughout the brain. Category I may represent early lymphoid tissue localization of PrP(res). The DMNV appears to be the most consistent single neuroanatomic site of detectable PrP(res). Categories 2-4 may represent a progression of spread of PrP(res) and SE throughout the brain. IHC in tonsil and brain and SE in brain were not detected in 208 control deer.     

Distribution of tissue enzymes in three species of pinnipeds.

In domestic animal medicine, changes in serum enzyme levels are routinely used as diagnostic tools to detect liver disease. Hepatic disease occurs in pinnipeds, but limited data are available on the tissue distribution of serum enzymes in marine mammals. The objectives of this study were to determine the tissue distribution of seven serum enzymes in three pinniped species. Enzymes evaluated were alanine aminotransferase (ALT), aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), lactate dehydrogenase (LDH), creatine kinase (CK), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT) in tissues from California sea lions (Zalophus californianus) (n = 5), harbor seals (Phoca vitulina) (n = 5), and northern elephant seals (Mirounga angustirostris) (n = 5) that stranded and then died at a rehabilitation center. Samples were evaluated in duplicate from liver, skeletal muscle, cardiac muscle, kidney, adrenal, spleen, pancreas, lung, lymph node, and intestine. Patterns of tissue enzyme distribution were similar in all species, with SDH activity highest in liver and kidney, CK activity highest in skeletal and cardiac muscle, ALP activity highest in adrenal, and GGT activity highest in the kidney. Aspartate aminotransferase and LDH activities were less specific, with high activity in multiple tissues. Tissue ALT activity was high in the liver of all species, but was also high in cardiac muscle (California sea lions), skeletal muscle (harbor seals), and kidney (elephant seals). These results suggest that concurrent analysis of SDH, ALT, and CK would provide high specificity and sensitivity for the detection of hepatic lesions, and allow differentiation of liver from skeletal muscle lesions in pinniped species.     

Generalized nodular dermatofibrosis in the absence of renal neoplasia in an Australian Cattle Dog

A 13-year-old, spayed, female Australian Cattle Dog had at least a 10-year history of numerous subcutaneous nodules for which fine-needle aspiration and cytologic evaluation were nondiagnostic. Abdominal ultrasound 3.5 months before necropsy detected a small left kidney but no cysts or neoplasms. At gross necropsy, innumerable, firm, round to oval, white, 0.25 to 2 cm masses were detected throughout the subcutaneous tissues of the axial and appendicular skeleton, epimysium of numerous muscles, and parietal peritoneum of the lateral abdominal body wall. The left kidney was approximately half the size of the right, and there was severe bilateral renal medullary (papillary) necrosis. Histologically, the subcutaneous nodules were well-demarcated masses of mature, hypocellular collagen that were consistent with previous reports of nodular dermatofibrosis and renal cystadenomas or cystadenocarcinomas. In addition to diffuse acute medullary necrosis, both kidneys were affected by severe chronic lymphoplasmacytic interstitial nephritis. This is the first known report of nodular dermatofibrosis in a dog without renal cysts, cystadenoma, or cystadenocarcinoma.     

Molecular diversity and population structure of the Ethiopian lentil (<Emphasis Type="Italic">Lens Culinaris</Emphasis> Medikus) genotype assessment using SSR markers

Knowledge of genetic diversity in germplasm is essential for formulating effective germplasm collection, conservation, utilization strategies in and crop improvement programs. It also provides an opportunity to take corrective steps infusing new genes to avoid risks associated with a narrow genetic bases. Genetic diversity analysis of 119 lentil genotypes of including 83 germplasm and 36 exotic genotypes from International Center for Agricultural Research in the Dry Areas was studied using 27 primers of simple sequence repeat (SSR) marker. Molecular analysis of variance showed variations of 82% within and 18% of the among population variance was explained. Degree of polymorphism observed among the populations was 100%. A total 122 alleles were detected, with 2 to 7 alleles per locus, with a mean of 4.52 alleles per locus. The estimated gene diversity value for 27 loci was 0.64. The average Shannon’s information index value of 1.19 was obtained showed the existence of high genetic variation within the genotypes. The genetic similarity indices ranged from 0.21 to 1.00. The SSR markers showed an average polymorphic information content (PIC) value of 0.58. Cluster analysis grouped the genotypes into five major clusters as distinct genetic populations. Diversity analyses revealed the existence of a high level of genetic variation among genotypes. This molecular diversity information provides a basis for future germplasm collection, utilization, and conservation strategies in gene banks and introducing exotic germplasm to widen the genetic base of the current lentil breeding population.     

Buffalo (Bubalus bubalis) Pre-antral Follicle Population and Ultrastructural Characterization of Antral Follicle Oocyte

The main objectives of the present study were to determine the ultrastructural modifications occurring in the oocyte during late folliculogenesis and to estimate pre-antral follicle population in buffalo. Half the collected ovaries were fixed and prepared for optic microscopy; the antral follicles from the other ovaries were measured and individually punctured. The cumulus–oocyte complexes (COCs) were processed for transmission electron microscopy. The number of pre-antral follicles in buffalo ovaries was estimated at 19 819 structures. Cumulus–oocyte complexes derived from 1-mm antral follicle had an eccentrical nucleus and compact corona radiata , ooplasm vilosities were fully embedded in zona pellucida (ZP) and a well-defined junction could be observed. Mitochondria were predominantly round and well distributed in ooplasm, as were small lipid vacuoles. In COCs derived from 2-mm antral follicles, the initial formation of perivitelline space was observed. The nucleus was peripherally located and the number of pleomorphic mitochondria increased. Cortical granules were clustered at oocyte periphery and lipid vacuoles increased in number and size. In COCs derived from 6-mm antral follicles, the organelles were located mainly in the perinuclear region. Golgi complexes and smooth endoplasmic reticulum (SER) were more developed. Mitochondria migrated to the cortical region and lipid vacuoles migrated to the medullar region. In COCs derived from 10-mm antral follicles, the lipid vacuoles coalesced and occupied the medullar region of the oocyte, together with a well-developed SER. Mitochondria were pleomorphic and located at the oocyte periphery. In conclusion, the morphological differences described in this paper could be responsible for some functional differences observed in in vitro embryo production and follicular dynamics for buffalo, when compared with cattle.