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An abstract of the dissertation of Abbas Sadeghi for the Doctor of Philosophy in Environmental Sciences and Resources: Biology presented on May 7, 1998. Title: Gene expression in two cyanobacteria, freshwater Synechococcus sp. PCC 7942 and oceanic Synechococcus sp. WH 7803, in response to ammonium, nitrate or iron. The transcriptional response of freshwater Synechococcus sp. PCC 7942 and oceanic Synechococcus sp. WH 7803 to ammonium, nitrate or iron was studied in single or multiple factor limited cultures. Both strains showed maximum production of NiR mANA when grown in nitrate-containing media. When grown in ammonium-containing medium, they did not show any signal for NiR mRNA synthesis. The influence on the transcription of NiR mRNA by iron as sole limiting nutrient was also evaluated. Iron increased the NiR mRNA whether or not the positive effect of nitrate was already present. The hybridization signal of mRNA for the large subunit of ribulose bisphosphate carboxylase/oxygenase enzyme (rbcl), was increased in both strains when iron was added. The relative response of NiA was larger than that of rbcL to iron addition. In the final set of experiments, combinations of iron, ammonium, or nitrate nutrient limitation were studied to understand their interactive effect on NiA and rbcL mANA production. The ammonium-grown cells were allowed to starve for iron and then transferred to +iron+nitrate, +iron-nitrate, or -iron+nitrate cultures. rbcL mANA was increased gradually up to 168 hr. NiA mANA increased initially but, for unknown reasons, decreased after 24 hr to a minimum that was similar for +iron+nitrate, +iron-nitrate, and -iron+nitrate cultures. A comparison of the rbcL or NiA mANA from multiple nutrient limitation with that of single nutrient limitation showed different time dependent patterns of synthesis. The response to iron starvation could be different when cells experience a co-limitation with nitrate. This response is also influenced by species specific differences by evolutionary adaptation to different environments. This difference is confirmed in the NiR and rbcL mANA response in two strains of marine and freshwater Synechococcus for single (iron) or multiple (iron+nitrate) limitation. Physiological studies commonly assume a single factor will constrain cell growth at any moment and when conditions change, the limiting factor will switch. The differential response in the synthesis of NiA and rbcl mANA observed shows that cells exhibit unique responses to combined limitations. GENE EXPRESSION IN TWO CYANOBACTERIA, FRESHWATER SYNECHOCOCCUS SP. PCC 7942 AND OCEANIC SYNECHOCOCCUS SP. WH 7803, IN RESPONSE TO AMMONIUM, NITRATE OR IRON

The main aim of the present research paper is to gather, analyze and interpret the perceptions of the Academic Staff Members (ASMs) about University student deep learning (USDL) held by 180 in the 2008-2009 academic years. ASMs randomly selected from each of the populations of ASMs in three different faculties, Humanities and Agricultural and physical Faculties. A 35 items scale questionnaire was developed based upon a review of literature on USDL. The final scale in last part of questionnaire asked them to bear in mind a particular teaching and learning process they judged deep and effective and to indicate to Likert 4 points scale the degree to which what ASMs exhibited their perceptions to the each of the items. Pilot study has been done in order to have enough validity and reliability (87% Chronbach Alpha correlation coefficient). The ASMs responses were analyzed for the purpose of the identifying the USDL purposed by each of the 35 items. Their responses were first analyzed for the identifying those items, most frequently and highly rated. Following, thus, factor analysis were performed to identify the factors which affect the USDL. Six areas were investigated and were named ASM’ characteristics, university student characteristics, academic activities, teaching process, learning process and classroom atmospheres.

This paper reports a case study conducted on an experienced based of the writer at Guilan University, into the affecting the Classroom Psychological Environment (CPE) on approaches of student learning in Guilan university. It focused on nine subscales of the CPE such as involvement, affiliation, teacher support, task orientation, competition, order & organization, rule clarity, teacher control and innovation. The paper concluded that the subscale of involvement had the largest discrepancy between preferred and actual form and the subscale of competition had the smallest discrepancy. The subscale of involvement also produced the highest mean in the preferred form indicating that students in general preferred a more affinitive classroom environment in which they can help each other with homework and have good relationship with others. While the subscale of competition resulted in Guilan University are greatly influenced by the examination system in that they prefer the actual very competitive learning environment in order to achieve higher grades.

The lower Oligocene hyaline and porcellaneous larger foraminifera of a carbonate platform setting, north of Sonqor, were studied for high-resolution biostratigraphy in the context of European standard zonation (Shallow Benthic Zones). According to the geological map of Kermanshah, these beds were previously ascribed to the Miocene. The identified larger foraminifera include Nummulites fichteli Michelotti, Nummulites vascus Joly & Leymerie, Operculina complanata (Defrance), Asterigerina rotula (Kaufmann), Planorbulina bronnimanni Bignot & Decrouez, Discogypsina discus (Goës), Gypsina mastelensis Bursch, Halkyardia maxima Cimerman, Stomatorbina concentrica (Parker & Jones), Praerhapydionina delicata Henson, Penarchaias glynnjonesi (Henson), Austrotrillina aff. paucialveolata Grimsdale, and Haddonia heissigi Hagn, associated with the coralline alga Subterraniphyllum thomasii Elliott. The foraminiferal association characterises the SBZ 21 Zone (early Rupelian)., Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy), V. 124, N. 2 (2018)