Characterization of air-sea gas exchange processes and dissolved gas/ice interactions using noble gases

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 1997In order to constrain the processes controlling the cycles of biogeochemically important gases such as 02 and C02, and thereby infer rates of biological activity in the upper ocean or the uptake of radiatively important "greenhouse" gases, the noble gases are used to characterize and quantify the physical processes affecting the dissolved gases in aquatic environments. The processes of vertical mixing, gas exchange, air injection, and radiative heating are investigated using a 2 year time-series of the noble gases, temperature, and meteorological data from Station S near Bermuda, coupled with a 1- dimensional upper ocean mixing model to simulate the physical processes in the upper ocean. The rate of vertical mixing that best simulates the thermal cycle is 1.1±0.1 x104 m The gas exchange rate required to simulate the data is consistent with the formulation of Wanninkhof (1992) to ± 40%, while the formulation of Liss and Merlivat 1986 must be increased by a factor of 1.7± 0.6. The air injection rate is consistent with the formulation of Monahan and Torgersen (1991) using an air entrainment velocity of 3±1 cm s1. Gas flux from bubbles is dominated on yearly time-scales by larger bubbles that do not dissolve completely, while the bubble flux is dominated by complete dissolution of bubbles in the winter at Bermuda. In order to obtain a high-frequency time-series of the noble gases to better parameterize the gas flux from bubbles, a moorable, sequential noble gas sampler was developed. Preliminary results indicate that the sampler is capable of obtaining the necessary data. Dissolved gas concentrations can be significantly modified by ice formation and melting, and due to the solubility of He and Ne in ice, the noble gases are shown to be unique tracers of these interactions. A three-phase equilibrium partitioning model was constructed to quantify these interactions in perennially ice-covered Lake Fryxell, and this work was extended to oceanic environments. Preliminary surveys indicate that the noble gases may provide useful and unique information about interactions between water and ice.This work has been supported by the National Science Foundation - OCE 9302812 and DPP 9118363, the Ocean Ventures Fund Ditty Bag Fund and Westcott Fund and the WHOI Education Office

Evaluation of maximum and total open surface evaporation by using trend analysis method in Nigde province of Turkey

This study was carried out Center of Nigde Province in Turkey. Trend analysis was performed on monthly total and maximum open surface evaporation data. In the study, a total of 42 years of data between 1978-2019 was used monthly. The data of the climate station in the center of Niğde province were used in the research. For many years, the maximum and total open surface evaporation data were applied to Mann-Kendall, Sperman’s Rho correlation tests and Sen's slope method. According to the research results; for many years, the total monthly open surface evaporation averages were 215,1 mm in June, 272,2 mm in July and 259,5 mm in August. For many years, the total evaporation in the summer months was recorded as 746,8 mm and the average evaporation as 248,9 mm. Maximum of the total open surface evaporation for many years in Niğde Center was calculated as 10,5 mm in June, 11,5 mm in July and 10,7 mm in August. The average of the total monthly open surface evaporation observed in the summer months is 10,9 mm. According to the trend analysis results made in Niğde Center, it has been observed that there is an increasingly significant trend in the monthly total and maximum open surface evaporation data for many years

Evaluation of monthly maximum, minimum and average temperature changes observed for many years in Nevsehir province of Turkey

In this research, minimum, maximum and average temperature values ​​between 1970 and 2019 in Center of Nevşehir Province, Ürgüp and Avanos districts in Turkey were examined. Sperman Rho and Mann Kendall statistical correlation tests were used in the analysis phase. As a result, the trends of temperature changes in years are revealed. According to trend analysis results, the average minimum temperature for long years in Avanos district is calculated as -1.20 °C. Maximum temperature is 26,6 °C and the average of all temperature values ​​is 12.18 °C. The average minimum temperature for many years in center of Nevsehir province is calculated as -1.99 0C, the maximum temperature is 24 0C and the average of all temperature values ​​is calculated as 10.73 0C. In Ürgüp district, the minimum temperature for long years was calculated as -4.20 0C, the maximum temperature is 18.48 0C, and the average of all temperature values ​​are 10.32 0C. As a results; It has been observed that there were increasing trend in years of spring, winter, autumn and summer in Nevsehir province and No trend was observed in Avanos and Ürgüp districts at maximum temperature values. While increasing trend is observed in Avanos district and Nevşehir Province in minimum temperature parameters, no change was observed in Ürgüp district. Increasing changes were observed in the average temperatures in all districts

Can the delta neutrophil ındex be used as a preliminary biomarker ın the evaluation of periodontal disease: a pilot study

Objective: Tissue destruction in periodontal diseases is related to inflammatory mediators in the host. However, it is unknown whether a relationship between delta neutrophil index (DNI) and neutrophil-lymphocyte ratio (NLR) in Stage 3 Grade A patients occurs. This cross-sectional study aimed to investigate the relationship between periodontal disease and DNI and NLR. Methodology: The study included 74 systemically healthy, non-smoking adults separated into 3 groups. Group 1: 26 subjects with good periodontal health, Group 2: 26 subjects with gingivitis, and Group 3: 22 subjects with Stage 3 Grade A periodontitis. After determining which group the patient will be included in, a clinical periodontal examination was made of each patient and pocket depth (PD), clinical attachment level (CAL), gingival index (GI), bleeding on probing (BOP) and plaque index (PI) parameters were measured. Venous blood samples were taken and examined with an automatic hematology analyzer for DNI, immature granulocytes (IG), NLR, C-reactive protein (CRP), procalcitonin, neutrophil count and lymphocyte count. Results: DNI, IG, CRP, and neutrophil count were observed to be highest in Group 3, followed by Group 2, and the difference between the groups in these parameters was determined to be statistically significant (p<0.001, p<0.001, p=0.046, p=0.016). DNI, IG, CRP and neutrophil count were observed to be positively correlated with periodontal parameters. Conclusion: The findings of this study support the role of DNI as a new biomarker for periodontal diseases. DNI may better reflect the systemic level of stage 3 grade A periodontitis than traditional inflammatory markers

PRELIMINARY STUDY OF FISH DIVERSITY IN PABEAN BAY, INDRAMAYU

Pabean Bay is an estuary waters in which salinity fluctuations occur. This fluctuation requires that the fish living in this location have the ability to adapt. This research is a preliminary study that aims to identify the diversity of fish species in these waters. The study was conducted from January to June 2015 with sampling at intervals of one month. Fishing was carried out at three stations, namely the inside which is the estuary of the river, the middle part and the outside of the estuary to get a representative sample. The fishing gear used are sero, and trammel nets. During the study, it was found that 78 species of fish were included in 39 families. The number of species in each sampling varies. Among the fish found were mainly the family Gobiidae (10 species) and the Family Leiognathidae, Lutjanidae, Sciaenidae and Tetraodontidae (four species each). Several fish species were found in the larval, juvenile and adult stages, and these conditions illustrate the importance of estuaries in the survival of the fish life cycle

Diet of Scalloped Perchlet, Ambassis Nalua (Hamilton, 1822) in Pabean Bay, West Java

Penelitian ini bertujuan untuk menganalisis jenis makanan ikan seriding (Ambassis nalua) menurut waktu dan ukuran panjang ikan. Penelitian dilaksanakan di perairan Teluk Pabean, Indramayu dari bulan Juli hingga Desember 2015. Penangkapan ikan dilakukan pada tiga zona, yaitu bagian dalam yang berupa muara sungai, bagian tengah, dan bagian luar estuari dengan interval satu bulan. Alat tangkap yang digunakan adalah sero dan jaring. Analisis makanan menggunakan Indeks Bagian Terbesar. Jumlah ikan seriding yang diamati saluran pencernaannya adalah 407 ekor dengan komposisi betina 283 ekor, jantan 118 ekor, dan yuwana 6 ekor. Ikan seriding merupakan ikan karnivora dengan menu makanan terdiri atas empat kelompok organisme yaitu krustase, yuwana ikan, amfipoda, dan isopoda. Ikan seriding menunjukkan menu makanan utama yang sama yaitu krustase baik berdasarkan waktu maupun ukuran ikan

Phase--coherence Effects in Antidot Lattices: A Semiclassical Approach to Bulk Conductivity

We derive semiclassical expressions for the Kubo conductivity tensor. Within our approach the oscillatory parts of the diagonal and Hall conductivity are given as sums over contributions from classical periodic orbits in close relation to Gutzwiller's trace formula for the density of states. Taking into account the effects of weak disorder and temperature we reproduce recently observed anomalous phase coherence oscillations in the conductivity of large antidot arrays.Comment: 11 pages, 2 figures available under request, RevTe

Nonlinear magnetotransport shaped by Fermi surface topology and convexity in WTe2

The nature of Fermi surface defines the physical properties of conductors and many physical phenomena can be traced to its shape. Although the recent discovery of a current-dependent nonlinear magnetoresistance in spin-polarized non-magnetic materials has attracted considerable attention in spintronics, correlations between this phenomenon and the underlying fermiology remain unexplored. Here, we report the observation of nonlinear magnetoresistance at room temperature in a semimetal WTe2, with an interesting temperature-driven inversion. Theoretical calculations reproduce the nonlinear transport measurements and allow us to attribute the inversion to temperature-induced changes in Fermi surface convexity. We also report a large anisotropy of nonlinear magnetoresistance in WTe2, due to its low symmetry of Fermi surfaces. The good agreement between experiments and theoretical modeling reveals the critical role of Fermi surface topology and convexity on the nonlinear magneto-response. These results lay a new path to explore ramifications of distinct fermiology for nonlinear transport in condensed-matter