Minimum area requirements of breeding birds in fragmented woodland of Central Argentina

The breeding avifauna of 25 woodland fragments (0.85–280 ha) was studied between 1996 and 2004 in Córdoba, Argentina. A distinctive feature of the avifauna of the fragments studied is the low area requirement of most of the species. Of the 54 woodland species recorded, 32 (59.3%) require c . 1 ha and 43 (79.6%) needed no more than 3 ha. Also noticeable is the relatively high number of individuals of most of the species. Both characteristics suggest a good tolerance to fragmentation. However, nine species (16.7%), the area-sensitive species, need fragments of 80 ha or larger. Moreover, eight resident species have apparently become extinct in the fragments that were studied, including the five large species that originally inhabited the area. Proportional odds and log linear models were fitted to relate the minimum area requirements of these species to various ecological characteristics (body size, diet, habitat use, migratory status, and nest type). Closed nesters, resident, woodland exterior, and medium-size species were the groups requiring larger areas. No apparent pattern was observed between area requirements and diet. A recent law prohibits woodland removal, which is a positive step towards the conservation of the fragments. The results suggest that as long as the present amount of woodland is maintained, the situation of the avifauna of the fragments is relatively secure, at least in the short term.     

Out-of-school experience categories influencing interest in biology of secondary school students by gender: exploration on an Abu Dhabi sample

This study employed the international Relevance of Science Education questionnaire to survey the interest in biology and the out-of-school experiences of Abu Dhabi secondary school students (median age 17, mean age 17.53 and mode age of 16) in the third semester of 2014. It included 3100 participants. An exploratory factor analysis was used to categorise the items for both interest in biology and out-of-school experience. Ten interest in biology and 12 out-of-school experience factors were extracted. The summated means for each factor indicated that ‘health and fitness’ and ‘disease control’ enjoyed highest interests among students. For out-of-school experiences, the two factors of ‘digital applications’ and ‘medical treatment’ received the highest scores. Multivariate analysis of variance revealed that all factors for both interest in biology and out-of-school experience exhibited significant differences between boys and girls. More girls than boys were interested in disease control, reproduction (human biology), alternative science, health and fitness, zoology, and applied cosmetic biology. No significant differences were observed for the remaining five other categories. Furthermore, analysis of variance revealed significant differences between boys and girls with regard to individual items comprising each of the factors. The highest correlations were between the two factors of out-of-school experiences of ‘the natural world’ and ‘learning through observation’ and the interest in biology factor related to ‘plant and animal farming and agriculture’. Results suggested that more emphasis must be placed on students’ out-of-school experience and their engagement in informal learning in contextual outdoor environments to enhance their interest in learning more about biology and the living environment in general.     

Correlations between the psychological peculiarities of an individual and the efficacy of a single neurofeedback session (by the EEG characteristics)

Modifications of different EEG rhythms induced by a single neurofeedback session (by the EEG characteristics) directed toward an increase in the ratio of the spectral powers (SPs) of the α vs θ oscillations were compared with the psychological characteristics of the tested subjects (the group included 30 persons). A generally accepted neurofeedback technique was used; the intensity of acoustic white noise served as the feedback signal. EEG potentials were recorded from the C3 and C4 leads. Psychological testing was carried out using Eysenck’s (EPQ), Rusalov’s (OST), and (16 PF) questionnaires. The directions of changes in the SPs of EEG frequency components were found to significantly correlate with some individuality-related peculiarities of the tested subjects. The SP of the δ rhythm correlated with the EPQ scale “neuroticism,” OST scale “social plasticity,” and 16 PF factors H (“parmia”), I (“premsia”), and Q₃ (“self-control of behavior”). The SP of the θ component demonstrated correlations with the OST scales “ergisity,” “plasticity,” and “social temp” and with 16 PF factors M (“autia”), Q₄ (“frustration”), and Q1 (“exvia”). The SP of the α rhythm correlated with 16 PF factors Q₃ (“self-control of behavior”), G (“strength of superEgo”), O (“hypothymia”), L (“protension”), and N (“shrewdness”). The SP of the β rhythm correlated with the OST scale “emotionality,” while that of the γ rhythm showed correlations with the 16 PF indices L (“protension”) and M (“autia”). Changes in the ratio of the α vs θ SPs correlated with the EPQ scale “neuroticism.” Thus, our data confirm the statement that a high individual variability of the results of a single (first in the series) neurofeedback session is to a great extent related to peculiarities of the individual psychological pattern of the subject. Neirofiziologiya/Neurophysiology, Vol. 38, No. 3, pp. 239–247, May–June, 2006.     

The Role of Intuitive Ontologies in Scientific Understanding – the Case of Human Evolution

Psychological evidence suggests that laypeople understand the world around them in terms of intuitive ontologies which describe broad categories of objects in the world, such as ‘person’, ‘artefact’ and ‘animal’. However, because intuitive ontologies are the result of natural selection, they only need to be adaptive; this does not guarantee that the knowledge they provide is a genuine reflection of causal mechanisms in the world. As a result, science has parted ways with intuitive ontologies. Nevertheless, since the brain is evolved to understand objects in the world according to these categories, we can expect that they continue to play a role in scientific understanding. Taking the case of human evolution, we explore relationships between intuitive ontological and scientific understanding. We show that intuitive ontologies not only shape intuitions on human evolution, but also guide the direction and topics of interest in its research programmes. Elucidating the relationships between intuitive ontologies and science may help us gain a clearer insight into scientific understanding.     

水杨酸调控盐胁迫下羽衣甘蓝种子萌发的机理

盐胁迫是植物种子萌发与植株生长的重要限制因子。以羽衣甘蓝(Brassica oleracea var.acephala)名古屋为材料,研究不同盐分对其种子萌发的影响,探索水杨酸(SA)及其合成抑制剂氨基茚磷酸(AIP)处理对羽衣甘蓝种子萌发的调控效应。实验结果表明,150与200 mmol·L^–1 NaCl处理后的羽衣甘蓝种子活力显著降低。盐胁迫显著降低种子的吸水速率、种子活力与幼苗质量,降低苯丙氨酸裂解酶活性与内源SA含量,提高过氧化氢(H2O2)与超氧阴离子(O2^–.)含量。SA可以缓解盐胁迫对羽衣甘蓝种子活力的抑制作用,通过促进内源SA合成,从而提高种子吸水率与种子活力,促进种子对K^+、Mg^2+的吸收,降低Na+含量。此外,外源施加SA能够显著增强超氧化物歧化酶和过氧化物酶活性,降低H2O2与O2^–.的积累。相反,氨基茚磷酸(AIP)处理能够增强盐胁迫对种子萌发的抑制作用,推测这与AIP处理能够显著降低种子内源SA含量密切相关。研究表明外源SA主要通过提高保护酶活性、降低活性氧积累和维持体内离子平衡来增强羽衣甘蓝的耐盐性。     

Die Entwicklung der Zellforschung

Obwohl erst im 17. Jahrhundert begonnen, hat die Zellforschung doch bald zur Formulierung allgemein-biologischer Theorien geführt und trägt auch heute ständig weiter zu fundamentalen Theorienbildungen bei. Die Entwicklung der Zellforschung verdient daher als Paradigma für die Gewinnung naturwissenschaftlicher Einsichten besonderes Interesse: An ihr können Grundbedingungen wissenschaftlichen Erkenntnisfortschrittes gut verdeutlicht werden als Wechselspiel von Methodenerweiterung und Konzeptualisierung des Neuentdeckten. Erst eineinhalb Jahrhunderte nach der Erstbeobachtung von Zellen gelang die Formulierung der “Zellentheorie”. Auf der durch sie geschaffenen, konzeptionellen Grundlage war es vielen biologischen und medizinischen Disziplinen möglich, von einem beobachtend-beschreibenden (“induktiven”) zu einem experimentierenderklärenden (“deduktiven”) Status vorzustoßen. Ein außergewöhnlicher Erfolg war dabei der Cytogenetik beschieden. Dagegen war der Versuch, in den subzellulären und submikroskopischen Bereich vorzudringen, nur teilweise erfolgreich (Polarisationsmikroskopie, Nägelis Micellartheorie). Ein breiter Durchbruch gelang in diesem Sektor erst um 1950 durch eine beinahe einmalige zeitliche Kumulierung methodischer Fortschritte, wobei vor allem Zellfraktionierung und Elektronenmikroskopie eine entscheidende Rolle spielten. Zusammen mit der vorausgegangenen Entwicklung “flankierender” Wissenschaften (insbesondere der Makromolekularen Chemie) wurde so die Etablierung der modernen Zellbiologie möglich. Einige ihrer bedeutendsten Aussagen werden diskutiert (Zellkompartimentierung und genetische Kontinuität ohne Nucleinsäuren; Zweiteilung der Organismenwelt nach der Zellorganisation; Evolution zellulärer Organismen und Symbiontentheorie). Abschließend wird versucht, Bedingungen und Erfordernisse von wissenschaftlichem Fortschritt allgemein zu formulieren und daran die heutige Wissenschaftswirklichkeit kritisch zu messen.     

The role of protein quality control in mitochondrial protein homeostasis under oxidative stress

Mitochondria contribute significantly to the cellular production of ROS. The deleterious effects of increased ROS levels have been implicated in a wide variety of pathological reactions. Apart from a direct detoxification of ROS molecules, protein quality control mechanisms are thought to protect protein functions in the presence of elevated ROS levels. The reactivities of molecular chaperones and proteases remove damaged polypeptides, maintaining enzyme activities, thereby contributing to cellular survival both under normal and stress conditions. We characterized the impact of oxidative stress on mitochondrial protein homeostasis by performing a proteomic analysis of isolated yeast mitochondria, determining the changes in protein abundance after ROS treatments. We identified a set of mitochondrial proteins as substrates of ROS‐dependent proteolysis. Enzymes containing oxidation‐sensitive prosthetic groups like iron/sulfur clusters represented major targets of stress‐dependent degradation. We found that several proteins involved in ROS detoxification were also affected. We identified the ATP‐dependent protease Pim1/LON as a major factor in the degradation of ROS‐modified soluble polypeptides localized in the matrix compartment. As Pim1/LON expression was induced significantly under ROS treatment, we propose that this protease system performs a crucial protective function under oxidative stress conditions.     

Anatomical Studies of Citrus jambhiri Lush. Roots Infected by Pratylenchus coffeae

All motile stages of Pratylenchus coffeae infected mature and immature tissues of Citrus jambhiri (rough lemon) seedling tap roots. The nematodes fed primarily in the cortex and colonized in pockets or cavities. Intra- and intercellular migration within the cortex occurred in either direction from the point of entry. When P. coffeae invaded a root tip the meristem often was destroyed and lateral root initiation usually occurred near the destroyed root tip. Males were essential for reproduction and survived at least 2 1/2 months within root tissues, but with males alone used as inoculum, no cortical pockets were formed. On infected trees in the field P. coffeae were most numerous in C. jambhiri feeder roots.     

A Cross-linking Mass Spectrometry Approach Defines Protein Interactions in Yeast Mitochondria

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Highlights

• •XL-MS reveals new PPIs in yeast mitochondria under glycerol and glucose condition.
• •Significant but limited results from quantitative XL-MS experiments.
• •Ndi1 participates in a CIII₂CIV₂ respiratory supercomplex.
• •Min8 promotes assembly of Cox12 into an intermediate complex IV.