Novel Papillomaviruses in Free-Ranging Iberian Bats: No Virus-Host Co-evolution, No Strict Host Specificity, and Hints for Recombination

Papillomaviruses (PVs) are widespread pathogens. However, the extent of PV infections in bats remains largely unknown. This work represents the first comprehensive study of PVs in Iberian bats. We identified four novel PVs in the mucosa of free-ranging Eptesicus serotinus (EserPV1, EserPV2, and EserPV3) and Rhinolophus ferrumequinum (RferPV1) individuals and analyzed their phylogenetic relationships within the viral family. We further assessed their prevalence in different populations of E. serotinus and its close relative E. isabellinus. Although it is frequent to read that PVs co-evolve with their host, that PVs are highly species-specific, and that PVs do not usually recombine, our results suggest otherwise. First, strict virus-host co-evolution is rejected by the existence of five, distantly related bat PV lineages and by the lack of congruence between bats and bat PVs phylogenies. Second, the ability of EserPV2 and EserPV3 to infect two different bat species (E. serotinus and E. isabellinus) argues against strict host specificity. Finally, the description of a second noncoding region in the RferPV1 genome reinforces the view of an increased susceptibility to recombination in the E2-L2 genomic region. These findings prompt the question of whether the prevailing paradigms regarding PVs evolution should be reconsidered.

The isolation and partial biochemical analysis of Sindbis virus proteins

Recently, the amino acid sequences have been reported for several proteins, including the envelope glycoproteins of Sindbis virus, which all probably span the plasma membrane with a common topology: a large N-terminal, extracellular portion, a short region buried in the bilayer, and a short C-terminal intracellular segment. The regions of these proteins buried in the bilayer correspond to portions of the protein sequences which contain a stretch of hydrophobic amino acids and which have other common characteristics, as discussed. Reasons are also described for uncertainty, in some proteins more than others, as to the precise location of some parts of the sequence relative to the membrane.

The signal hypothesis for the transmembrane translocation of proteins is briefly described and its general applicability is reviewed. There are many proteins whose translocation is accurately described by this hypothesis, but some proteins are translocated in a different manner.

The transmembraneous glycoproteins E1 and E2 of Sindbis virus, as well as the only other virion protein, the capsid protein, were purified in amounts sufficient for biochemical analysis using sensitive techniques. The amino acid composition of each protein was determined, and extensive N-terminal sequences were obtained for E1 and E2. By these techniques E1 and E2 are indistinguishable from most water soluble proteins, as they do not contain an obvious excess of hydrophobic amino acids in their N-terminal regions or in the intact molecule.

The capsid protein was found to be blocked, and so its N-terminus could not be sequenced by the usual methods. However, with the use of a special labeling technique, it was possible to incorporate tritiated acetate into the N-terminus of the protein with good specificity, which was useful in the purification of peptides from which the first amino acids in the N-terminal sequence could be identified.

Nanomole amounts of PE2, the intracellular precursor of E2, were purified by an immuno-affinity technique, and its N-terminus was analyzed. Together with other work, these results showed that PE2 is not synthesized with an N-terminal extension, and the signal sequence for translocation is probably the N-terminal amino acid sequence of the protein. This N-terminus was found to be 80-90% blocked, also by Nacetylation, and this acetylation did not affect its function as a signal sequence. The putative signal sequence was also found to contain a glycosylated asparagine residue, but the inhibition of this glycosylation did not lead to the cleavage of the sequence.

A influência do corte com diferentes discos e velocidades na integridade dos espécimes e na resistência adesiva de uma cerâmica a um cimento resinoso dual em ensaio de microtração

Esta pesquisa estudou a influência de diferentes velocidades de corte e marcas de discos diamantados nos valores de resistência adesiva, durante a preparação dos espécimes a serem submetidos à microtração, e na integridade das amostras por meio do microscópio eletrônico de varredura (MEV). Vinte blocos da cerâmica à base de dissilicato de lítio (IPS e.max Press) foram unidos com cimento resinoso (Rely X ARC) a blocos de compósito (Z100), construídos incrementalmente. Foram seguidas as recomendações dos fabricantes no tratamento da superfície da cerâmica e aplicação do cimento resinoso. Após 24 horas em água destilada a 37C, os espécimes foram divididos em dois grupos de discos: marcas Buehler e Extec e subdivididos nas velocidades de 200rpm e 400rpm (B2; E2; B4 e E4, respectivamente). Cada espécime foi cortado em dois eixos perpendiculares para obtenção de palitos com área adesiva de 1,0mm. Para cada condição experimental, os palitos foram separados, aleatoriamente, 15 palitos para análise ao MEV e 30 palitos para serem submetidos à força de tração. As médias de resistência adesiva em MPa foram E4=20,312 ; B4= 24,2 11,3 ; B2= 25,2 9,0 e E2= 28,6 10,4. Na análise estatística, observou-se que os valores de resistência adesiva na velocidade de 200rpm foram significativamente maiores comparados a velocidade de 400rpm, independente do disco empregado. Ao MEV, observou-se melhor integridade dos palitos na velocidade de 200rpm com presença de trincas menos extensas nas bordas externas. Constatou-se também que o disco Extec na velocidade de 400rpm apresentou movimentos excêntricos ao corte e obteve-se maior número de perdas prematuras, uma diminuição significante na média da área total de união (p<0,05), além de diferença significativa nos valores de resistência comparada a velocidade de 200rpm. Concluiu-se que a utilização de diferentes velocidades e sua interação com o disco empregado interfere na integridade dos espécimes e nos valores de resistência adesiva, sendo mais acentuada ao se utilizar o disco da marca Extec.

A study of the ^9 Be nucleus

The reaction ⁷Li(³He, p)⁹Be has been used to measure excitations and intrinsic widths of levels in ⁹Be below the ⁷Li + d threshold. Previously unreported levels have been found at excitations of (13.78 ± .03) MeV and (16.671 ± .008) MeV with widths of (590 ± 60) keV and (41 ± 4) keV respectively. Two overlapping levels have been found at (11.81 ± .02) MeV and (11.29 ± .03) MeV with widths of (400 ± 30) keV and (620 ± 70) keV respectively. Branching ratios from ⁹Be levels populated in this reaction to the ground and first excited states of ⁸Be have been measured by observing the associated protons in coincidence with the decay neutrons. Branching ratios were found to be:

Excitation in ⁹Be .... Branching Ratio.......... Final Nucleus.........

(MeV) .......................... (percent) .....................................

.. 2.43 ........................... 7.5 ± 1.5 .............. ⁸Be(g.s.)

.. 3.03 ........................... 87 ± 13......................................

.. 4.65 ........................... 13 ± 4.......................................

.. 6.76 .............................. ≤ 2 ......................................

.. 11.29 ...............................≤ 2 ......................................

.. 11.81 ...............................≤ 3 ......................................

.. 6.76 ........................... .41 ≤ B.R. ≤ .69 ....... ⁸Be(2⁺)

.. 11.29 ........................... 14 ± 4 .......................................

.. 11.81 ........................... 12 ± 4 .......................................

Corresponding reduced widths for neutron emission are calculated and a comparison of the results with the expectations of current nuclear models is made. In particular the measured branching ratio to ⁸Be(g.s.) from ⁹Be(2.43 MeV) corresponds to an f-wave reduced with θ²_f = 2.1 x 10^-2, in units of ħ²/mR², with R = 4.35 fm. A comparison of this value with that predicted by a Nilsson model calculation, in which ⁹Be is taken to be a deformed nucleus, is discussed. The measured value for θ²_f is found to be consistent with that expected on the basis of measured E2-transition rates between rotational levels in ⁹Be.

Beta and gamma vibrational bands in deformed nuclei

Energies and relative intensities of gamma transitions in ¹⁵²Sm, ¹⁵²Gd, ¹⁵⁴Gd, ¹⁶⁶Er, and ²³²U following radioactive decay have been measured with a Ge(Li) spectrometer. A peak fitting program has been developed to determine gamma ray energies and relative intensities with precision sufficient to give a meaningful test of nuclear models. Several previously unobserved gamma rays were placed in the nuclear level schemes. Particular attention has been paid to transitions from the beta and gamma vibrational bands, since the gamma ray branching ratios are sensitive tests of configuration mixing in the nuclear levels. As the reduced branching ratios depend on the multipolarity of the gamma transitions, experiments were performed to measure multipole mixing ratios for transitions from the gamma vibrational band. In ¹⁵⁴Gd, angular correlation experiments showed that transitions from the gamma band to the ground state band were predominantly electric quadrupole, in agreement with the rotational model. In ²³²U, the internal conversion spectrum has been studied with a Si(Li) spectrometer constructed for electron spectroscopy. The strength of electric monopole transitions and the multipolarity of some gamma transitions have been determined from the measured relative electron intensities.

The results of the experiments have been compared with the rotational model and several microscopic models. Relative B(E2) strengths for transitions from the gamma band in ²³²U and ¹⁶⁶Er are in good agreement with a single parameter band mixing model, with values of z₂= 0.025(10) and 0.046(2), respectively. Neither the beta nor the gamma band transition strengths in ¹⁵²Sm and ¹⁵⁴Gd can be accounted for by a single parameter theory, nor can agreement be found by considering the large mixing found between the beta and gamma bands. The relative B(E2) strength for transitions from the gamma band to the beta band in ²³²U is found to be five times greater than the strength to the ground state band, indicating collective transitions with strength approximately 15 single particle units.

O papel da proteína supressora de tumor p53 na indução de ciclooxigenase-2 em Carcinoma de Pulmão de Células Não Pequenas: aspectos moleculares e clínicos

O Carcinoma de Pulmão de Células Não Pequenas (NSCLC) é uma doença freqüentemente letal e altamente resistente à terapia oncológica convencional, como por exemplo, o tratamento quimioterápico com cisplatina e paclitaxel. A superexpressão de Ciclooxigenase-2 (COX-2) é constantemente observada em pacientes com NSCLC, estando associada ao prognóstico ruim destes pacientes. Acredita-se que a alta expressão de COX-2 produz efeitos anti-apoptóticos, porém pouco é conhecido sobre os mecanismos de regulação desta enzima. Muitos sinais capazes de ativar COX-2 também induzem a proteína supressora de tumor p53, conhecida pelo seu papel fundamental no controle da proliferação celular e apoptose. Dados recentes indicam que a proteína p53 é um importante regulador da expressão de COX-2. O objetivo desta dissertação foi avaliar os efeitos da quimioterapia na expressão da enzima COX-2 em linhagens celulares com diferente status do gene TP53, e ainda, correlacionar a expressão de COX-2 e o status mutacional de TP53, com as características clínico-patológicas de pacientes com NSCLC. Como ferramentas experimentais foram usadas técnicas de biologia celular e molecular como interferência de RNA, PCR em tempo real, análise mutacional e imuno-histoquímica. Com os resultados obtidos, observamos que as linhagens celulares de câncer de pulmão que apresentam p53 na sua forma selvagem, quando expostas ao tratamento com cisplatina, apresentaram indução da expressão de COX-2 (RNAm e proteína), em adição ao aumento da síntese de Prostaglandina E2 (PGE2). Em contrapartida, a expressão de COX-2 não foi alterada após o tratamento com cisplatina nas linhagens celulares que apresentavam mutação no gene TP53. Ao avaliar o tratamento com paclitaxel, foi observado um aumento da expressão de COX-2 nas linhagens A549 e H460 (linhagens celulares do tipo selvagem para p53), entretanto não foi observada alteração nos níveis de PGE2. Em adição, o tratamento com paclitaxel induziu um aumento da expressão de COX-2 na linhagem com deleção em TP53, ACC LC-319. Em seguida, após silenciamento de p53 na linhagem celular A549, por interferência de RNA, a cisplatina passou a não ser mais capaz de induzir o aumento da expressão de COX-2. No tratamento com paclitaxel, o silenciamento de TP53 não mudou a expressão de COX-2, indicando assim um efeito independente de p53. Dessa maneira, sugerimos que a indução de COX-2, por cisplatina, em linhagens celulares NSCLC é dependente de p53. Na análise dos pacientes NSCLC, os resultados demonstram que 54% dos pacientes apresentam expressão positiva de COX-2. Mutações em TP53 foram observadas em 57% dos pacientes, incluindo 56% de fumantes correntes e 37% de ex-fumantes. Uma associação entre a expressão de COX-2 e o status selvagem de TP53 foi observada, entre os pacientes que apresentaram expressão positiva de COX-2, 80% apresentaram TP53 selvagem. Um número maior de pacientes é necessário para aumentar o poder estatístico e confirmar as tendências observadas nesse estudo

γ-LiAlO_2上a面ZnO薄膜的光谱特性研究

利用激光脉冲沉积(PLD)技术在(302)γ-LiAlO2衬底上成功生长了非极性的a面(1120)ZnO薄膜,光致发光谱(PL)带边发射峰半峰宽仅为115meV.研究了非极性ZnO薄膜光谱特性的面内各向异性,发现随着入射光偏振方向改变,在偏振透射光谱上,吸收边移动了20meV,这与A、B激子和C激子的能量差一致;而在拉曼光谱上,激发光偏振方向的改变导致E2模式的强度发生明显改变.

Novel Papillomaviruses in Free-Ranging Iberian Bats: No Virus-Host Co-evolution, No Strict Host Specificity, and Hints for Recombination

Papillomaviruses (PVs) are widespread pathogens. However, the extent of PV infections in bats remains largely unknown. This work represents the first comprehensive study of PVs in Iberian bats. We identified four novel PVs in the mucosa of free-ranging Eptesicus serotinus (EserPV1, EserPV2, and EserPV3) and Rhinolophus ferrumequinum (RferPV1) individuals and analyzed their phylogenetic relationships within the viral family. We further assessed their prevalence in different populations of E. serotinus and its close relative E. isabellinus. Although it is frequent to read that PVs co-evolve with their host, that PVs are highly species-specific, and that PVs do not usually recombine, our results suggest otherwise. First, strict virus-host co-evolution is rejected by the existence of five, distantly related bat PV lineages and by the lack of congruence between bats and bat PVs phylogenies. Second, the ability of EserPV2 and EserPV3 to infect two different bat species (E. serotinus and E. isabellinus) argues against strict host specificity. Finally, the description of a second noncoding region in the RferPV1 genome reinforces the view of an increased susceptibility to recombination in the E2-L2 genomic region. These findings prompt the question of whether the prevailing paradigms regarding PVs evolution should be reconsidered.

HPV infection, a described cause for human cancer: HPV detection and molecular mechanisms of HPV carcinogenesis (Review).

[en]Human papillomavirus (HPV) belongs to the Papillomaviridae virus family and it is one of the most common sexual transmission infections. HPV genome is composed of eight genes, including two early genes and six late genes. Among these late genes, E6 and E7 code for proteins that trigger cell-cycle re-entry in infected cells, which can lead to cervical cancer development. The IARC (International Agency for Research Cancer) proposed a guideline based on Hill’s criteria to determine whether the relation between HPV infection and cervical cancer is causal or not. Epidemiological studies have demonstrated that HPV infection is a necessary but non-sufficient cause for cervical cancer. Furthermore, HPV infection is considered the first necessary cause described of a human cancer, being HPV16 and 18 carcinogenic to humans and the most studied types. Cervical cancer is the second leading cause of cancer death among women worldwide. Different screening programs are carried out with the aim of preventing cervical cancer; such as cytologies and HPV tests. There are two main methods which are equally usable to detect HPV: the real-time PCR assays and the array assays. Regarding the molecular mechanisms of HPV mediated malignancies, E2, E6 and E7 proteins of HPV16 lead to immune response evasion, inducing IL-10 and TGF-β1 gene expression. Besides, E6 and E7 proteins allow cell-cycle reentry, phosphorylating RB and ubiquitinating p53 respectively. HPV genome integration in host genome leads to the alteration of host and viral genes expression, including oncogenes and tumor suppressor genes. However, the differences of E6 and E7 oncoproteins in different HPV types is poorly known due to the fact that almost the most studied HPV type has been HPV16.

Ocorrência e ecotoxicidade de desreguladores endócrinos químicos em ambientes aquáticos e em sistemas de tratamento de esgoto

A aplicabilidade de um método selecionado de medição indireta de vitelogenina (Vtg) em plasma sanguíneo de peixe, baseado na quantificação de fosfato álcali-lábil (alkali-labile phosphate-ALP) para acessar estrogenicidade em água, foi investigada na presente tese. O método foi originalmente desenvolvido para a espécie de peixe Carassius carassius (Carpa cruciana) e aplicado pela primeira vez na espécie Oreochromis niloticus (Tilápia do Nilo) no presente estudo. Com o objetivo de acessar a sensibilidade do método, em uma primeira etapa da investigação foram realizados estudos laboratoriais com soluções estoques de 17-ethinylestradiol (EE2), 17-estradiol (E2), e estrona (E1). Os efeitos destes hormônios foram investigados com base tanto na concentração quanto na carga, utilizando-se para tanto, unidades experimentais com volumes distintos (2 L e 130 L). Após a validação do método de ALP, a estrogenicidade foi avaliada nas seguintes águas contaminadas: (i) afluente e efluente de uma grande estação de tratamento de esgotos convencional (ETE) e de uma estação descentralizada de tratamento de esgoto de pequeno porte (Ecossistema Engenheirado-DEE); (ii) água superficial (SW) e água subterrânea (GW) coletadas em uma área de brejo contaminada com gasolina; (iii) água de uma lagoa urbana (LRF) da cidade do Rio de Janeiro, com alta densidade populacional e descarte clandestino de esgoto. Na segunda etapa foram analisados em microalgas os efeitos (outros que não disrupção endócrina) causados pelos hormônios EE2, E2 e E1. Os hormônios foram testados individualmente e em misturas, em culturas individuais e combinada (S+) das espécies de microalgas unicelulares P. subcapitata e D. subspicatus. Com base nos níveis de ALP para a espécie de peixe e no EC50 para as espécies de algas, os resultados mostraram que o EE2 e o E2 causaram disrupção endócrina superior e foram mais tóxicos do que o E1 para peixes e microalgas respectivamente. Quando em misturas (E+) de concentrações equivalentes (EE2:E2:E1), os estrogênios resultaram em efeito aditivo para as espécies O. niloticus e P. subcapitata, e menos que aditivo para D. subspicatus e cultivo misto de algas (S+). Culturas contendo ambas as espécies de algas (S+) por um longo período de exposição (96 h) resultaram na atenuação dos efeitos tóxicos causados pela exposição, tanto individual (EE2, E2 ou E1), quanto na mistura (E+) dos estrogênios, medidos em termos de EC50 (T0h 0,07; 0,09; 0,18; e 0,06 g mL-1; e T96h 1,29; 1,87; 5,58; e 4,61 g mL-1, respectivamente). O DEE apresentou uma maior eficiência na remoção dos disrutores endócrinos do que a ETE convencional. Foi detectada estrogenicidade em amostras da LRF, e de água SW e GW em área brejosa contaminada com gasolina. Os resultados dos ensaios sugerem que as interações (efeitos aditivos ou menos que aditivo) causadas pela mistura dos estrogênios assim como, as interações entre as espécies de algas afetaram o resultado final dos ensaios ecotoxicológicos. Um fator raramente abordado em estudos ecotoxicológicos que foi destacado na presente tese refere-se à importância de considerar não somente a concentração e a dosagem, mas também a carga aplicada e o volume das unidades experimentais. Devido à boa sensibilidade do O. niloticus quando exposto às concentrações relativamente baixas dos estrogênios, a combinação do método de ALP com os biomarcadores auxiliares (particularmente MN) pode ser um protocolo adequado para a detecção de estogenicidade e genotoxicidade respectivamente em diferentes ambiente aquáticos contaminados, como parte de um programa de monitoramento ambiental

水稻胚囊发育畸变的细胞学和遗传学研究

1．水稻多卵卵器的起源：被子植物的卵器中通常只有一个卵细胞。我们在水稻多胚品系胚囊中观察到二卵卵器和三卵卵器，本研究对其大孢子发生和胚囊发育进行了细胞胚胎学观察，揭示了水稻多卵卵器的起源．观察结果表明，该品系能进行正常的大孢子发生。大孢子母细胞进行正常的减数分裂形成四个大孢子靠近合点端的大孢子发育，其它三个退化。功能大孢子第一次有丝分裂后两个子核被一中央大液泡分隔在胚囊珠孔端和合点端，与此同时胚囊出现不均衡生长，珠孔端迅速膨大，合点端几乎不增大，致使二核末期的胚囊呈倒梨形．紧接着发生第二次有丝分裂，合点端核分裂时纺锤丝与胚囊纵轴平行，而珠孔端核分裂时纺锤丝与胚囊纵轴成4 5度夹角．由此产生的四核胚囊中，合点端一核向胚囊中部或中上部（胚囊珠孔端）迁移，四核胚囊再经一次有丝分裂形成两种类型的核分布偏离蓼型的八核胚囊。一种类型是珠孔端四个核，中部与合点各二个核，在胚囊细胞化过程中，珠孔端四核 分化成四细胞卵器，其中卵细胞和助细胞各二个，中部的二核分化成二极核中央细胞，合点 端的二核形成反足细胞。另一种类型是珠孔端六个核，合点端二个核，在胚囊细胞化过程中， 两端各一核向中部迁移分化成二极核中央细胞，珠孔端剩余的五核分化成五细胞卵器，其 中卵细胞三个，助细胞二个，合点端的一核迅速分裂形成反足细胞． 2．水稻同源三倍体TAR的生殖特性：TAR的单穗结实率平均可达10%，核型分析表明此三倍体产生的后代个体仍为具有36条染色体的三倍体．细胞胚胎学初步观察显示TAR为一具兼性无融合生殖特性的水稻新种质，其胚珠几乎都能进行胚囊的分化，但其中仅有33%的胚囊有较正常的结构，9%的胚囊在散粉前进行胚胎发生，58%的胚囊发育显著异常，表现为极性紊乱、多极核或缺失雌性生殖单位等。 3．水稻亚种间杂种败育的细胞学基础：对普通栽培稻不同品种类型间杂种颖花败育的细胞学基础及雌性败育的过程进行的细胞学研究表明：1）引起杂种颖花败育的原因有胚囊败育，花粉败育、开花时花药不开裂和雌雄异熟．其中胚囊败育而丧失受精能力是引起低结实率的最重要的因素，开花时花药不开裂和雌雄异熟在一定程度上形成了雌雄性细胞时间和空间的隔离屏障。2）杂种植株的所有大孢子母细胞都能进行正常的减数分裂形成四个大孢子，败育主要发生在靠近合点端的功能大孢子分化形成胚囊的早期，有的胚囊母细胞在进行第一次有丝分裂前便萎缩解体，多数能完成一次或二次有丝分裂形成二核或四核败育胚囊．败育的共同特征是无液泡的分化，细胞质少或退化，在败育胚囊残迹部位，解体的珠心细胞和萎缩的胚囊残溃混杂垛叠．已受精的杂种子房没有观察到胚及胚乳发育的异常．籼粳杂种胚囊败育频率较高． 4．籼粳杂种生殖障碍的基因定位：应用具有1 37个标记位点的籼粳杂交窄叶青8号/京系17)F1花药培养获得的127个双单倍体OH）群体构建的R FLP图谱，对控制籼粳杂种颖花败育的基因座位进行了定位研究。结果在第1、3、4、5、6、7、8、1 2染色体上检测到1 0个基因座位，其中第3、12染色体上的2个不育基因位点str3和str12与同一杂交组合F2分离群体中发现的异常分离热点处于相同的染色体区段．stj-6的基因加性效应为负值，有增加籼粳亲和性的作用;其余的不育基因座位皆有增加籼梗杂种不育性的作用． 5．籼粳杂种胚囊败育的遗传分析和基因定位：利用DH系构建的分子图谱及DH系衍生的2个回交群体定位了引起籼梗杂种胚囊败育的2个互补的主效基因esa-l（E1或e1位点）和esa-2（E2或e2位点），它们分别位于第6和第1 2染色体．在不育基因位点，籼稻基因型为EIEle2e2，粳稻基因型为elelE 2E 2，杂交后代中基因型为EIE2，Ele2、elE 2的雌配子体正常发育，携带ele2基因型的雌配子体表现败育．胚囊育性受配子体基因型控制，孢予体遗传背景影响胚囊败育基因的表达.

全球变化的植被——环境相关性：中国和东北样带（NECT）研究

全球变化与陆地生态系统(GCTE)的研究一直是国际地圈一生物圈计划(IGBP)．全球变化研究的焦点之一，其中植被与环境，尤其是气候的关系研究，虽然古老却又包含许多新的涵义，而陆地样带(Terrestrial Transect)则是近年来发起于GCTE，并拓展到IGBP其它核心项目的研究热点．博士后研究的主要工作有：将全球变化作为主线，以单个树种青冈(Cyclobalanopsisgtauco)为对象，研究其过去、现在和将来的地理分布与气候的关系;分别利用气温和降水指标，拓展Kira指标形成生物热量指数和干湿度指数，以及建立水热积指数，在宏观尺度上研究了中国植被与气候的关系;结合生物群区和植物功能型概念的发展以及生物多样性的研究，进行了以生物多样性保育为目的的我国生态地理区划;在熟悉IGBP陆地样带的科学计划并总结其最新发展动态的基础上，分析了中国东北样带的基本生态地理特征;最后，粗略分析r生物性多样保育与自然保护区建设和管理的关系问题。 1.植被一环境（气候）分类：指标、系统和模型 植被一气候关系是一个古老的命题，但在当今的全球变化研究中成为最基础和最具活力的工作。从单一因子的或多因子简单组合的分类指标，如Koppen，Box指标等，到以可能蒸散为基础的综合分类指标，如Penman，Thornthwaite, Holdridge，Budyko，Kira指标等，科学家们发展了众多的植被一气候分类系统和模型，如Koppen．Thornthwaite，Holdridge. Kira. Box. Neilson.Woodward, Budyko, Prentice系统，以及Holdridge，Uvardy，Matthews. Olson. Bailey．Woodward.Prentice. Box模型，为现今植被一气候关系的研究以及全球变化对陆地生态系统的影响，和大气C02增加对潜在植被变化的响应预测奠定了良好的基础。 2.基于物种的植被一气候关系研究：中国青冈的地理分布与气候的关系 在广泛收集青冈[Cyclobalanopsis glauca (Thunb.) Oerst.]地理分布资料的基础上，利用目前国际上比较流行的研究植被与气候相互关系的指标和方法，包括Kira的水热指标、Penman的公式、Thomthwaite的指标和气候分类、Holdridge的生命地带分类系统指标， 以及年平均气温(TEMP). 1月均温(Tl)、’7月均温(T7)、极端最高气温(TMAX)、极端最低气温(TMIN).≥10℃积温(AT)和年降水量(PREC)，研究了青冈在中国的地理分布与气候的关系，讨论了青冈垂直分布的上限、下限以及北界的Kira热量指标状况。根据孢粉资料和历史文献，探讨r历史时期青冈在中国大陆的分布与变迁及其与气候的关系，并利用Holdridge生命地带分类系统指标预测了C02浓度倍增条件下中国青冈分布区的可能变化。 3.宏观尺度上的中国植被一气候关系 1）用气温、降水指标研究中国植被一气候关系 能够在气象台站直接、方便地测试到的年平均气温、降水量指标，与其它水热气候因子有显著的相关性，用它们来研究中国植被与气候的关系是可行且有用的。利用全国689个气象站点的气象记录，计算得出了中国各植被地带、亚地带的年平均气温，年降水量指标和温雨系数，利用生态信息系统EIS作出了各气候指标在中国的分布，并将年平均气温和降水量作散点图，均较好地表现了中国各植被类型与气候指标的关系和格局。总结可得中国各植被地带的气候指标范围及界限。综合孢粉，古生物等资料信息，前人确定在全新世中期中国存在一个大暖期，其中稳定暖湿的鼎盛阶段在7.2—6,0 Ka．B.P.，其时中国境内大部分地区的年平均气温比现在高2℃左右，年降水平均高于现在100 mm，通过数学处理，利用生态信息系统恢复重建了全新世大暖期中国大陆的气温和降水分布状况．参考孢粉、古植物和他人研究资料及现代植被气候关系，恢复编制了大暖期鼎盛阶段中国大陆的植被区划图，与现代植被区划相比较，东部各个植被带在大暖期盛时表现出明显的北迁，温带植被的迁移幅度大于亚热带和热带植被;西部的植被带出现了经向西迁，西北部的草原范围扩张，荒漠缩小;青藏高原地区高寒半荒漠和荒漠植被的范围大大缩小，而且植被带仍有不同程度向北迁移的表现。这可为预测与阐明未来的气候变化和植被变迁提供有力的证据． 2）KIRA指标的拓展及其在中国植被与气候关系研究中的应用 根据Kira以月平均气温5℃为界的热量指数和干湿度指数概念，提出了以月平均气温10℃为界的生物热量指数，包括生物温暖指数BWI和生物寒冷指数BCI，并修正其干湿度指数为生物干湿度指数BK。利用中国689个标准气象台站的资料，分析我国主要植被类型分布与热量因子和干湿度因子的关系，得出两者之间有较好的相关性，生物温暖指数、寒冷指数和干湿度指数的散点图，较好地表现了中国各植被类型与气候指标的关系和格局。并得出中国各植被地带的气候指标范围及界限，以1 0℃为界的生物温暖指数不仅对我国森林植被的地理分布和温度气候带的划分具有较好的指示作用，而且对西南部高山、亚高山地区的植被与气候关系指示性较强;生物寒冷指数则对亚热带和热带的指示性很好，能够较好区分亚热带南部及热带地区;由热量指数和降水量综合得出的生物干湿度指数，对中国西北部干旱、半干旱区以至全国的植被分布与水分、热量因子的关系分析有较好的应用价值。 3）水热积指数的估算及其在中国植被与气候关系研究中的应用 试图利用大气年平均气温、年降水量、可能蒸散和土壤水分平衡之间的关系建立一个水热积指数，并应用年平均气温．水分盈亏值和水热积指数三个气候变量来限定植物群落组合，构成一个圆形的生命-气候图式．根据全国689个标准气象台站的气候资料，计算了中国8个植被地带和26个亚地带的年平均气温、年水分盈亏和水热积指数，绘制了各气候指标在中国的分布图及散点图，较好表现了中国各植被类型与气候指标的关系和格局，包括寒温带针叶林、冷温带针阔叶混交林、暖温带落叶阔叶林、亚热带常绿阔叶林、热带雨林和季雨林、温带草原、温带荒漠、青藏高原高寒植被，并得到了中国各植被地带的气候指标范围及界限。通过分析可以看出，年平均气温的等值线较好地反映了中国大陆的热量梯度，经度和纬度方向的区分均较明显;土壤水分盈亏曲线的等值线则比较零乱;综合了热量和水分差异的水热积指数，其等值线与热量梯度和水分梯度均有一定的对应性，与植被类型的对应也较好。这是在宏观尺度上进行的植被与气候关系研究的一种尝试，有待于增加机理性的内容，使其得到进一步的改进。 4.生物多样性保育和全球变化研究中的陆地生物群区类型 Biome(生物群区)是当今生物多样性保育和全球变化研究中的一个重要概念，根据此概念及植物功能型概念的发展，评述了9个重要的世界陆地生物群区分类系统，并根据中国的植被分类和区划，尝试划分了在中国的生物多样性保育和全球变化研究中所需要的陆地生物群区类型。 5.中国生物多样性的生态地理区划 利用各种生态地理因子，包括气候指标如与植物耐寒性有关的绝对最低温度(TMrN)，最冷月平均气温(TJAN)，最冷月日平均温度的最大值(MXT)和最小值(MIT);与需热性有关的植物生长季积温(AT);年降水量的季节分配，包括最冷月降水(PJAN)，最热月降水(PJUL)，年降水量，年降水的统计标准差(PSD)和变异系数(年变率PCV);植被指标如植被类型(VEGET)、，植被区划类型(VEGED)、植被的净第一性生产力(NPP)、植物区系类型(FLORA)、动物区系类型(FA UNA).植物特有属的丰富度(EDGENUS)以及度量植物多样性的植物种丰富度(属数GENUS、种数SPECIES);土壤指标如土壤类型(SOILT)，土壤理化性质如土壤酸碱度(SOILPH)、土壤表层阳离子交换量(SOILEXC)等;地形和地貌特征如经度(LONG)、纬度(LAT)和海拔高度(ALT)，利用模糊聚类的手段，综合进行了中国生物多样性的生态地理区划。采用四级区划，即：生物大区(biodomain) -生物亚区(subbiodomain) -生物群区(biome) -生物区(bioregion).全国划分为5个生物大区，7个生物亚区和1 8个生物群区。 I北方森林大区 I A欧亚北方森林亚区 I Al南泰加山地寒温针叶林 IA2北亚针阔叶混交林 II北方草原荒漠大区 II B欧亚草原亚区 II Bl内亚温带高草草原 II B2黄土高原森林草原（灌木草原） il C亚非荒漠亚区 II Cl中亚温带荒漠 ⅡC2蒙古／内亚温带荒漠 III东亚大区 III D东亚落叶阔叶林亚区 m DI东亚落叶阔叶林 III E东亚常绿阔叶林亚区 III El东亚落叶•常绿阔叶混交林 III E2东亚常绿阔叶林 ⅡI E3东亚季风常绿阔叶林 III E4西部山地常绿阔叶林 IV旧热带大区 IV F印度一马来热带森林亚区 IV Fl北热带雨林、季雨林 IV F2热带海岛植被 V亚洲高原大区 vG青藏高原亚区V Gl青藏高寒灌丛草甸V G2青藏高寒草原V G3青藏高寒荒漠V G4青藏温性草原V Gs青藏温性荒漠IGBP陆地样带：科学计划与最新进展 作为国际地圈一生物圈计划(IGBP)的交叉项目(Interproject)的陆地样带(Terrestrial Transect)，已成为IGBP的全球变化研究中最引人重视的发展和新研究方法之一。它以一系列综合性的全球变化研究计划为基础，是由沿着一个主要全球变化驱动因素（如温度、降水、土地利用强度等）的梯度上的一系列研究站点所构成研究区域，并配合以模型模拟和综合分析，其地理范围为1000 km或更大的长度，数百公里的宽度，以涵盖大气环流模型(GCM)运作的最小单元。本节论述了IGBP陆地样带的概念和研究的意义，样带的类型、一般设计和选择标准，国际上IGBP样带的初步设置，包括①经受土地利用变化的潮湿热带系统;②从北方森林到冻原的高纬度地区;③从干旱森林到灌丛的半干旱热带地区;④从森林或灌丛过渡到草地的中纬度半干旱地区，以及其它的一些样带和PAGES核心计划中的PEP样带，主要内容有样带设置的原因、研究内容和主要样带特点等，并总结了样带的最新研究进展和动态． 6.中国东北样带(N ECT)的生态地理特征分析 陆地样带研究已成为国际地圈-生物圈计划(IGBP):全球变化研究的重要手段与热点。中国东北森林-草原样带(NECT)已被列为IGBP国际全球变化陆地样带之一。该样带在东经1120与130030’之间沿北纬43030’设置，长约l 600 km，是一条中纬度温带以降水为驱动因素的梯度，具有由温带针阔叶混交林向温带草原的3个亚地带：草甸草原、典型草原与荒漠草原过渡的空间系列。本文给出了样带的基本生态地理特征及其梯度分析，包括其地理位置、设置意义、地形地貌、气候梯度、土壤类型、土地利用格局、植被类型、主要优势种和群落类型的生态地理特征以及全新世适宜期（大暖期）的植被分布格局。NECT将成为我国全球变化与陆地生态系统(GCTE)与其它IGBP核心项目研究的前沿阵地。 7.自然保护区的作用、建设和管理及其与生物多样性的关系 一般而言，“就地保护”是保护生物多样性的主要措施和最根本的途径，生境的“就地保护”是生物多样性保护最为有力和最为高效的保护方法，而就地保护的措施就是建立自然保护区，通过对自然保护区的建设和有效管理，使生物多样性得到切实有效的人为保护。从自然保护区定义和类型划分及生物多样性的定义本身可以看出，自然保护区的主要保护对象是世界上丰富多彩的生物多样性，自然保护区是生物多样性就地保护的重要基地，是物种多样性的基因库，是留给野生动植物的宝贵栖息地，应把保护区的建设和生物多样性的保护与持续利用密切结合起来，合理开发利用自然资源，促进生物多样性的可持续发展。

生殖激素对奶水牛卵母细胞成熟及发育潜能的影响

本试验以屠宰场获取的奶水牛卵巢为试验材料,收集卵母细胞进行体外成熟培养(IVM)、体外受精(IVf)及早期胚胎培养(IVC).研究激素(FSH、LH、E2、P4)的不同浓度对奶水牛卵母细胞成熟和早期胚胎发育的影响,以期探讨奶水牛卵母细胞成熟和早期胚胎体外培养发育机制,优选不同激素的最佳浓度.结果表明:添加FSH试验组奶水牛颗粒细胞扩散率和卵裂率高于未添加试验组(P<0.05);添加LH试验组奶水牛颗粒细胞扩散率、卵裂率及8-细胞率与未添加试验组比较,差异不明显(P>0.05);17β-E2试验组(1.0μg/mL)的奶水牛颗粒细胞扩散率、卵裂率及8-细胞率高于未添加试验组(P<0.05);添加P4试验各组(0.9μg/mL、1.2μg/mL)的颗粒细胞扩散率明显低于未添加试验组(P<0.01).

Some socio-economic aspects of the fishermen of twin pronged floodplain wetlands in West Bengal

A socio-economic investigation was carried out in two fishermen cooperative societies namely Purba Helatala Fishermen Co-operative Society (E-1), Barhal Fishermen Co-operative Society (E-2), under Maldah district, West Bengal to which the beels (flood plains) under study belong. A total of 132 member fishermen, which constituted the sample, were personally interviewed. The age group of the fishermen of the sample in E-1 varied between 20 and 66 years whereas in E-2 it was 22 and 61 years. All the members of the sample belonged to Scheduled Caste (SC) community. The primary occupation of all the respondents of both the beels was observed to be fishing (100%). Maximum number of illiterate respondents was observed to 56% in E-2 and 35% in E-1. It has been observed that as many as 38.3% of fishermen were having fishing experience which ranging from 16 to 20 years in E-1 whereas it was 6 - 10 years (36.1%) in E-2. Maximum number of fishermen lived in thatched houses (41.66%) in E-1 whereas in E-2 most of them lived in houses made of corrugated tin/tile shed (41.66%). As many as 41.55% of E-1 and 30.55% of E-2 used dug-out canoes for their fishing. Maximum number of fishermen used cast net with individualistic approach (100%) followed by Gill net (E-1:41.56% and E-2:55.55%). Most of the fishermen of the sample participated in fishing activities for 241 to 270 days (41.66%) in E-2 whereas it was 211 to 240 days (33.33 %) in E-1 in a year. During fishing season as many as 40.0% of the respondents of E-1 earned on an average Rs. 801.00 to Rs. 900.00 per month whereas it was Rs. 901.00 to Rs.1,000.00 (43.05%) in case of E-2. A section of fishermen of the sample borrowed money often (51.6%) E-1 whereas it was most often (27.27%) of E-2. The respondents of E-2 made regular repayment of the loan to the maximum extent (79.48%) whereas it was 57.44% in E-1. Higher fish production vis-a-vis higher income for the fishermen was observed in the beel (E2) having close characteristic.