Estimation of zinc pheophytins, chlorophylls, and pheophytins in mixtures in diethyl ether or 80% acetone by spectrophotometry and fluorometry.     

I D Jones  R C White  E Gibbs  L S Butler 《Journal of agricultural and food chemistry》1976,25(1):146-149

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Initial results from long-term field studies at three sites on the effects of heavy metal-amended liquid sludges on soil microbial activity   总被引：1，自引：0，他引：1  

P. A. Gibbs    B. J. Chambers    A. M. Chaudri    S. P. McGrath  & C. H. Carlton-Smith   《Soil Use and Management》2006,22(2):180-187

In a long‐term study of the effects on soil fertility and microbial activity of heavy metals contained in sewage sludges, metal‐amended liquid sludges each with elevated Zn, Cu or Cd concentrations were applied over a 3‐year period (1995–1997) to three sites in England. The experiments were sited adjacent to experimental plots receiving metal‐rich sludge cakes enabling comparisons to be made between the effects of heavy metal additions in metal‐amended liquid sludges and sludge cakes. The liquid sludge additions were regarded as ‘worst case’ treatments in terms of likely metal availability, akin to a long‐term situation following sewage sludge additions where organic matter levels had declined and stabilised. The aim was to establish individual Zn (50–425 mg kg^?1), Cu (15–195 mg kg^?1) and Cd (0.3–4.0 mg kg^?1) metal dose–response treatments at each site, but with significantly smaller levels of organic matter addition than the corresponding sludge cake experiments. There were no differences (P > 0.05) in soil respiration rates, biomass carbon concentrations or most probable numbers of clover Rhizobium between the treatments at any of the sites at the end of the liquid sludge application programme. Soil heavy metal extractability differed between the metal‐amended liquid sludge and metal‐rich sludge cake treatments; Zn and Cd extractabilities were higher from the liquid sludge additions, whereas Cu extractability was higher from the sludge cake application. These differences in metal extractability in the treated soil samples reflected the contrasting NH₄NO₃ extractable metal contents of the metal‐amended liquid sludges and sludge cakes that were originally applied.  相似文献   

Genome-sequencing anniversary. Bringing genomics and genetics back together     

Gibbs RA 《Science (New York, N.Y.)》2011,331(6017):548

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Genetic determinants of self identity and social recognition in bacteria     

Gibbs KA  Urbanowski ML  Greenberg EP 《Science (New York, N.Y.)》2008,321(5886):256-259

The bacterium Proteus mirabilis is capable of movement on solid surfaces by a type of motility called swarming. Boundaries form between swarming colonies of different P. mirabilis strains but not between colonies of a single strain. A fundamental requirement for boundary formation is the ability to discriminate between self and nonself. We have isolated mutants that form boundaries with their parent. The mutations map within a six-gene locus that we term ids for identification of self. Five of the genes in the ids locus are required for recognition of the parent strain as self. Three of the ids genes are interchangeable between strains, and two encode specific molecular identifiers.  相似文献   

The molecular basis of the sparse fur mouse mutation   总被引：30，自引：0，他引：30  

G Veres  R A Gibbs  S E Scherer  C T Caskey 《Science (New York, N.Y.)》1987,237(4813):415-417

The ornithine transcarbamylase-deficient sparse fur mouse is an excellent model to study the most common human urea cycle disorder. The mutation has been well characterized by both biochemical and enzymological methods, but its exact nature has not been revealed. A single base substitution in the complementary DNA for ornithine transcarbamylase from the sparse fur mouse has been identified by means of a combination of two recently described techniques for rapid mutational analysis. This strategy is simpler than conventional complementary DNA library construction, screening, and sequencing, which has often been used to find a new mutation. The ornithine transcarbamylase gene in the sparse fur mouse contains a C to A transversion that alters a histidine residue to an asparagine residue at amino acid 117.  相似文献   

Generation of cDNA probes directed by amino acid sequence: cloning of urate oxidase   总被引：58，自引：0，他引：58  

C C Lee  X W Wu  R A Gibbs  R G Cook  D M Muzny  C T Caskey 《Science (New York, N.Y.)》1988,239(4845):1288-1291

Urate oxidase (E.C. 1.7.3.3) catalyzes the oxidation of uric acid to allantoin in most mammals except humans and certain primates. The amino-terminal amino acid sequence for porcine urate oxidase was determined and used in a novel procedure for generating complementary DNA (cDNA) probes to this amino acid sequence. The procedure is based on the polymerase chain reaction and utilizes mixed oligonucleotide primers complementary to the reverse translation products of an amino acid sequence. This rapid and simple cDNA cloning procedure is generally applicable and requires only a partial amino acid sequence. A cDNA probe developed by this procedure was used to isolate a full-length porcine urate oxidase cDNA and to demonstrate the presence of homologous genomic sequences in humans.  相似文献   

Infection as the etiology of spongiform encephalopathy (Creutzfeldt-Jakob disease)   总被引：7，自引：0，他引：7  

C J Gibbs  D C Gajdusek 《Science (New York, N.Y.)》1969,165(897):1023-1025

Fatal spongiform encephalopathy occurred in four chimpanzees 12 to 14 months after inoculation with suspensions of brain from four patients, respectively. Chimpanzee to chimpanzee transmission was effected without reduction in incubation period. Retransmission of the disease to a second chimpanzee occurred when an inoculum that had been stored at -70 degrees C for over 2 years was used.  相似文献   

AN ACCURATE DROP RECORDER     

Gibbs OS 《Science (New York, N.Y.)》1929,69(1799):649-650

An improved form of drop recorder is described which has an accuracy of 600 drops per cc.  相似文献   

Creutzfeldt-Jakob disease (spongiform encephalopathy): transmission to the chimpanzee   总被引：48，自引：0，他引：48  

C J Gibbs  D C Gajdusek  D M Asher  M P Alpers  E Beck  P M Daniel  W B Matthews 《Science (New York, N.Y.)》1968,161(839):388-389

Biopsy material taken from the brain of a patient with CreutzfeldtJakob disease with status spongiosus induced a similar fatal encephalopathy in a chimpanzee 13 months after inoculation.  相似文献   

Growth of Single Plant Cells     

Gibbs JL  Dougall DK 《Science (New York, N.Y.)》1963,141(3585):1059

Suspension of plant cells from tissue cultures have been plated in nutrient agar medium so that practically all of the individual cells yielded colonies.  相似文献