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 共查询到20条相似文献,搜索用时 15 毫秒
1.
Using newspapers in your science classroom;Ruth Jarman and Billy Mclune

Conventional or computer-based rat dissection?;Martin Predavec

Development of knowledge frameworks and higher order cognitive operations;Paul J Bischoff and O Roger Anderson  相似文献   

2.
Do young people understand cellular genetics?; Colin Wood-Robinson, Jenny Lewis, and John Leach

Do young people understand cellular genetics?; Din Yan Yip

Improve your students' understanding of ecology; Kathleen Hogan  相似文献   

3.
Letters     
Nuffield Advanced Biology; A. M. Lucas;

Assessment of projects; Colin Wood-Robinson  相似文献   

4.
Letters     
No more projects?; D. R. Holdford

SA/V ratios and gaseous exchange; Michael Reiss  相似文献   

5.
News     
Schools affiliation scheme

BES expedition grants

Fermenters for schools project; Jonathan Bach

Case studies in evolution  相似文献   

6.
Entry to medical schools; Harry Grenville

Nuffleld Advanced Biology

Environmental politics and policy

Grants for school nature areas

Biology in TVEI/CPVE courses - new handbook

New AV catalogue  相似文献   

7.
《Journal of bryology》2013,35(4):383-386
Abstract

Dicranella riparia is shown to be more appropriately treated as Kiaeria riparia comb. nov.; Kiaeria glacialis is shown to be a misfit in Dicranum; Oncophorus sardous is placed in synonymy of O. wahlenbergii; Arctoa anderssonii is shown to be a distinct species.  相似文献   

8.
Abstract

Vegetation and environment in the Marche and related problems of protection. – The « Marche » region is situated in central Italy and corresponds with the natural region east of the Appennine ridge and spreading as far as the coast which is washed by the Adriatic Sea.

As to the climate, we may distinguish a coastal strip with Mesomediterranean climate with dry season, corresponding to the distribution area of Quercus ilex; a hilly strip with Submediterranean climate, corresponding to the distribution area of Quercus pubescens; a mountain strip with temperate axeric climate with sub-dry period, corresponding to the distribution area of Fagus silvatica and finally a high mountain strip with cold axeric climate, corresponding to altitude pastures. The Marche vegetation is shown in the vegetation map of Fabriano sheet (scale 1:50,000) plotted according Ozenda's vegetational series.

The following vegetation series have been plotted: submediterranean series of Quercus ilex; series of thermophilic oak wood with priority of Quercus pubescens or Quercus cerris; series of Ostrya carpinifolia; series of Quercus petraea and series of Fagus silvatica.

As far as the problems to safegard environment are concerned, a plan is given providing for the institution of 4 complete nature reserves, 34 nature reserves, and 9 regional nature parks among which those of Monte Conero, of Monti Sibillini and Monti della Laga.  相似文献   

9.
Abstract

Duvaucel’s gecko is properly referred to as Hoplodactylus duvaucelii; other renderings of the specific epithet are incorrect. The existence of some historically important specimens of the species, including a newly rediscovered syntype, is noted.  相似文献   

10.
Summary

Saxifraga rosacea is recorded and Poa scotica described new to Scotland. The position of segregate taxa or breeding units within several species complexes is clarified within Scotland: (a) the hexaploid cytotype within the mostly tetraploid Campanula rotundifolia; (b) diploid Hedera helix and tetraploid H. hibernica;, (c) diploid and tetraploid Deschampsia cespitosa, D. alpina and D. parviflora; (d) octoploid sub-species scotica within usually hexaploid Festuca rubra; (e) an octoploid mountain Agrostis; (f) fertile hexaploid Potentilla anserina; (g) an approximately triploid aneuploid Vaccinium uliginosum ssp. microphyllum.  相似文献   

11.
Abstract

An analogue of the 2-5A core trimer containing an 8-(4-aminobutyl)-aminoadenosine (1; A) residue at the 2′(3′)-terminus [2; (2′,5′)A2A?] was synthesized. The conformation of (2′,5′)A2A? was studied by 1H, 13C-NMR, and CD spectroscopy. The (2′,5′)A2A? exhibits very low binding ability to the RNase L of mouse L cells, but slightly enhanced resistance to digestion by SVPD compared to the parent trimer.  相似文献   

12.
ABSTRACT

Three new species of Parhydraenida Balfour-Browne, 1975 are described from southeastern Brazil: P. plesioformis, sp. n.; P. proboscis sp. n.; P. unicornis sp. n. The genus Parhydraenida is recorded from Minas Gerais for the first time, and P. hygropetrica Perkins, 1980 is recorded from Rio de Janeiro for the first time. We describe one secondary sexual character, which enables, for the first time, unambiguous distinction of males and females. Habitus photographs as well as line drawings of the male and female genitalia of all three new species, and of P. hygropetrica are provided.

urn:lsid:zoobank.org:pub:CCA56FB6-897A-4128-B8DD-3892464A8D1B  相似文献   

13.
Objectives

This study aimed to screen, characterize, and annotate the genome along with the comparison of GABA synthesis genes presented in lactic acid bacteria (LAB).

Results

Thirty-five LAB isolates from fermented foods were screened for GABA production using thin-layer chromatography (TLC). Fifteen isolates produced GABA ranging from 0.07 to 22.94 g/L. Based on their GTG5 profiles, phenotypic, and genotypic characteristics, isolates LSI1-1, LSI1-5, LSI2-1, LSI2-2, LSI2-3, LSI2-5, and LSM3-1-4 were identified as Lactobacillus plantarum subsp. plantarum; isolate LSM1-4 was Lactobacillus argentoratensis; isolates CAB1-2, CAB1-5, CAB1-7, and LSI1-4 were Lactobacillus pentosus; and CAB1-1, LSM3-1-1 and LSM3-2-3 were Lactobacillus fermentum. Strains LSI2-1 and CAB1-7 from pickled vegetables were selected for genome analysis. The gadA gene (1410 bp, 470aa) was encountered in GABA production of both strains and no other glutamate decarboxylase (GAD) genes were found in the genomes when compared with other LAB strains. The presence of gadA is evidence for GABA production. Strains LSI2-1 and CAB1-7 produced 22.94 g/L and 11.59 g/L of GABA in GYP broth supplemented with 3% (w/v) MSG at 30 °C for 72 h, respectively.

Conclusions

Our report highlights the characterization of LAB and GABA production of L. plantarum LSI2-1 strain with its GABA synthesis gene.

Graphic abstract

GABA production of strains LSI2-1 and CAB1-7 in GYP broth with 3% (w/v) MSG and comparative GAD genes

  相似文献   

14.
15.
Abstract

The following weevil species are known from The Snares islands: Anthribidae — Cacephatus aucklandicus, Lichenobius littoralis; Curculionidae — Exeiratus laqueorum, Pentarthrum spadiceum, Notacalles planidorsis, Lyperobius sp., Hadramphus stilbocarpae, Phrynixus laqueorum, Gromilus laqueorum, Nestrius laqueorum, Catoptes brevicornis australis, Oclandius vestitus. The larvae and pupae are described and figured, and keys for their separation are given.  相似文献   

16.
Abstract

Conformational energy calculations were carried out on three non-peptide antagonists of oxytocin and vasopressin: penicilide (compound 1; selective for oxytocin receptors), 1- {1-[4-(3-acetylaminopropoxy (benzoyl]-4-piperidyl}-3,4-dihydro-2(1H)-quinoline (compound 2; selective for vasopressin V1 receptors) and 5-dimethylamino-1-{(2-methylbenzylamino)-benzoyl}-2,3,4,5–tetrahydro-1H-benzapine (compound 3; selective for vasopressin V2 receptors). The obtained low-energy conformations of compound 1 were compared with low-energy conformations of oxytocin (OT) and low-energy conformations of compounds 2 and 3 were compared with low-energy conformations of arginine vasopressin (AVP). It was found that the affinity of the non-peptide antagonists and their selectivity for vasopressin and oxytocin receptors is probably connected with mimicking the aromatic rings of the Tyr2 and the Phe3 residues of AVP in the case of compounds 2 and 3 and with mimicking the Tyr2 residue and the Ile3 or Leu8 residues of OT by the outer benzene ring and the isobutyl group of compound 1. Application of the results in the design of more potent non-peptide antagonists of OT and VP is also discussed.  相似文献   

17.
Background: Arundinarieae are a large tribe of temperate woody bamboos for which phylogenetics are poorly understood because of limited taxon sampling and lack of informative characters.

Aims: This study assessed phylogenetic relationships, origins and classification of Arundinarieae.

Methods: DNA sequences (plastid trnL-F; nuclear ITS) were used for parsimony and Bayesian inference including 41 woody bamboo taxa. Divergence dates were estimated using a relaxed Bayesian clock.

Results: Arundinarieae were monophyletic but their molecular divergence was low compared to the tropical Bambuseae. Ancestors of the Arundinarieae lineage were estimated to have diverged from the other bamboos 23 (15–30) million years ago (Mya). However, the Arundinarieae radiation occurred 10 (6–16) Mya compared to 18 (11–25) Mya for the tropical Bambuseae. Some groups could be defined within Arundinarieae, but they do not correspond to recognised subtribes such as Arundinariinae or Shibataeinae.

Conclusions: Arundinarieae are a relatively ancient bambusoid lineage that underwent a rapid radiation in the late Miocene. The radiation coincides with the continental collision of the Indo-Australian and Eurasian Plates. Arundinarieae are distributed primarily in East Asia and the Himalayas to northern Southeast Asia. It is unknown whether they were present in Asia long before their radiation, but we believe recent dispersal is a more likely scenario.  相似文献   

18.
Abstract

Germination and growth of ABIES ALBA mill. in different light and temperature conditions. — The results of a research on white fir from different localities are summarized as follows:

a) Germination of seeds from three italian localities (Tuscany, lat. 43°, 44'; Abruzzo, lat. 41°, 52'; Calabria, lat. 38°, 33') has been tested in several ecological conditions (temperature, light and chilling); it has been found that 22 °C, 8 hrs. of light and a 3 weeks prechilling at 5 °C, are stimulating conditions for all the seeds. The Cala-brian seeds seem the most reactive.

b) Growth in different photoperiodic conditions has been tested on seedlings from the Appennine, from France (lat. 49°, 10') and Poland (lat. 49°, 39'). Growth is evidently stimulated by long-day conditions in all the seeds experimented and growth acceleration touches its maximum in the Calabrian seedlings, provided they germinated at 12°C in the ligth.

It has been concluded that Calabrian Abies behaves as a Biotype, evidently distinguished from all the others, and an ecological explanation of this behaviour has been attemped.  相似文献   

19.
Riassunto

L'A. ha studiato l'embriogia della Vinea difformis Pourr. ed ha potuto stabilire che:

  1. l'archisporio è pluricellulare e possono svilupparis talvolta pi[ugrave] cellule madri;

  2. normalmente solo una cellula madre arriva a maturità;

  3. delle quattro megaspore solo una è fertile e precisamente la pi[ugrave] calazale;

  4. lo sviluppo del gametofito è del tipo Normale cioè Monomegasporiale con oangio emisporiale.

Ha inoltre risontrato una anomalia di sviluppo constituita da un gametofito binucleato abnorme per ritardo delle divisioni nucleari cispetto all'acerescimento che è quello di un gametofito ottonucleato.  相似文献   

20.
Abstract

Regeneration and totipotency.—Regeneration and totipotency of cells and nuclei in plants and animals are discussed. The paper consists of the following sections: regeneration in coelenterates and planarians; limb regeneration in amphibians; regeneration of mammalian liver; Wolffian lens regeneration in urodeles; nuclear transplantation in animal eggs; regeneration of plants from single cells (in vivo; in vitro; from somatic cell hybrids); general remarks.  相似文献   

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